This is ./gnutls.info, produced by makeinfo version 4.8 from
./gnutls.texi.

This manual is last updated 10 May 2012 for version 3.0.21 of GnuTLS.

Copyright (C) 2001-2012 Free Software Foundation, Inc.

     Permission is granted to copy, distribute and/or modify this
     document under the terms of the GNU Free Documentation License,
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INFO-DIR-SECTION Software libraries
START-INFO-DIR-ENTRY
* GnuTLS: (gnutls).		GNU Transport Layer Security Library.
END-INFO-DIR-ENTRY

INFO-DIR-SECTION System Administration
START-INFO-DIR-ENTRY
* certtool: (gnutls)Invoking certtool.	Manipulate certificates and keys.
* gnutls-serv: (gnutls)Invoking gnutls-serv.	GnuTLS test server.
* gnutls-cli: (gnutls)Invoking gnutls-cli.	GnuTLS test client.
* gnutls-cli-debug: (gnutls)Invoking gnutls-cli-debug.	GnuTLS debug client.
* psktool: (gnutls)Invoking psktool.	Simple TLS-Pre-Shared-Keys manager.
* srptool: (gnutls)Invoking srptool.	Simple SRP password tool.
END-INFO-DIR-ENTRY


File: gnutls.info,  Node: X509 certificate API,  Next: OCSP API,  Prev: Datagram TLS API,  Up: API reference

E.3 X.509 certificate API
=========================

The following functions are to be used for X.509 certificate handling.
Their prototypes lie in `gnutls/x509.h'.

gnutls_pkcs7_deinit
-------------------

 -- Function: void gnutls_pkcs7_deinit (gnutls_pkcs7_t PKCS7)
     PKCS7: The structure to be initialized

     This function will deinitialize a PKCS7 structure.

gnutls_pkcs7_delete_crl
-----------------------

 -- Function: int gnutls_pkcs7_delete_crl (gnutls_pkcs7_t PKCS7, int
          INDX)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     INDX: the index of the crl to delete

     This function will delete a crl from a PKCS7 or RFC2630 crl set.
     Index starts from 0. Returns 0 on success.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_delete_crt
-----------------------

 -- Function: int gnutls_pkcs7_delete_crt (gnutls_pkcs7_t PKCS7, int
          INDX)
     PKCS7: should contain a gnutls_pkcs7_t structure

     INDX: the index of the certificate to delete

     This function will delete a certificate from a PKCS7 or RFC2630
     certificate set.  Index starts from 0. Returns 0 on success.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_export
-------------------

 -- Function: int gnutls_pkcs7_export (gnutls_pkcs7_t PKCS7,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     PKCS7: Holds the pkcs7 structure

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a structure PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the pkcs7 structure to DER or PEM format.

     If the buffer provided is not long enough to hold the output, then
     * `output_data_size' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     PKCS7".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_get_crl_count
--------------------------

 -- Function: int gnutls_pkcs7_get_crl_count (gnutls_pkcs7_t PKCS7)
     PKCS7: should contain a gnutls_pkcs7_t structure

     This function will return the number of certifcates in the PKCS7
     or RFC2630 crl set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_get_crl_raw
------------------------

 -- Function: int gnutls_pkcs7_get_crl_raw (gnutls_pkcs7_t PKCS7, int
          INDX, void * CRL, size_t * CRL_SIZE)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     INDX: contains the index of the crl to extract

     CRL: the contents of the crl will be copied there (may be null)

     CRL_SIZE: should hold the size of the crl

     This function will return a crl of the PKCS7 or RFC2630 crl set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.  If the provided buffer is not
     long enough, then  `crl_size' is updated and
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  is returned.  After the last crl
     has been read `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be
     returned.

gnutls_pkcs7_get_crt_count
--------------------------

 -- Function: int gnutls_pkcs7_get_crt_count (gnutls_pkcs7_t PKCS7)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     This function will return the number of certifcates in the PKCS7
     or RFC2630 certificate set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_get_crt_raw
------------------------

 -- Function: int gnutls_pkcs7_get_crt_raw (gnutls_pkcs7_t PKCS7, int
          INDX, void * CERTIFICATE, size_t * CERTIFICATE_SIZE)
     PKCS7: should contain a gnutls_pkcs7_t structure

     INDX: contains the index of the certificate to extract

     CERTIFICATE: the contents of the certificate will be copied there
     (may be null)

     CERTIFICATE_SIZE: should hold the size of the certificate

     This function will return a certificate of the PKCS7 or RFC2630
     certificate set.

     After the last certificate has been read
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.  If the provided buffer is not
     long enough, then  `certificate_size' is updated and
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  is returned.

gnutls_pkcs7_import
-------------------

 -- Function: int gnutls_pkcs7_import (gnutls_pkcs7_t PKCS7, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT)
     PKCS7: The structure to store the parsed PKCS7.

     DATA: The DER or PEM encoded PKCS7.

     FORMAT: One of DER or PEM

     This function will convert the given DER or PEM encoded PKCS7 to
     the native `gnutls_pkcs7_t'  format.  The output will be stored in
     `pkcs7' .

     If the PKCS7 is PEM encoded it should have a header of "PKCS7".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_init
-----------------

 -- Function: int gnutls_pkcs7_init (gnutls_pkcs7_t * PKCS7)
     PKCS7: The structure to be initialized

     This function will initialize a PKCS7 structure. PKCS7 structures
     usually contain lists of X.509 Certificates and X.509 Certificate
     revocation lists.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_set_crl
--------------------

 -- Function: int gnutls_pkcs7_set_crl (gnutls_pkcs7_t PKCS7,
          gnutls_x509_crl_t CRL)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     CRL: the DER encoded crl to be added

     This function will add a parsed CRL to the PKCS7 or RFC2630 crl
     set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_set_crl_raw
------------------------

 -- Function: int gnutls_pkcs7_set_crl_raw (gnutls_pkcs7_t PKCS7, const
          gnutls_datum_t * CRL)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     CRL: the DER encoded crl to be added

     This function will add a crl to the PKCS7 or RFC2630 crl set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_set_crt
--------------------

 -- Function: int gnutls_pkcs7_set_crt (gnutls_pkcs7_t PKCS7,
          gnutls_x509_crt_t CRT)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     CRT: the certificate to be copied.

     This function will add a parsed certificate to the PKCS7 or
     RFC2630 certificate set.  This is a wrapper function over
     `gnutls_pkcs7_set_crt_raw()'  .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs7_set_crt_raw
------------------------

 -- Function: int gnutls_pkcs7_set_crt_raw (gnutls_pkcs7_t PKCS7, const
          gnutls_datum_t * CRT)
     PKCS7: should contain a `gnutls_pkcs7_t'  structure

     CRT: the DER encoded certificate to be added

     This function will add a certificate to the PKCS7 or RFC2630
     certificate set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_check_issuer
----------------------------

 -- Function: int gnutls_x509_crl_check_issuer (gnutls_x509_crl_t CRL,
          gnutls_x509_crt_t ISSUER)
     CRL: is the CRL to be checked

     ISSUER: is the certificate of a possible issuer

     This function will check if the given CRL was issued by the given
     issuer certificate.  It will return true (1) if the given CRL was
     issued by the given issuer, and false (0) if not.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_deinit
----------------------

 -- Function: void gnutls_x509_crl_deinit (gnutls_x509_crl_t CRL)
     CRL: The structure to be initialized

     This function will deinitialize a CRL structure.

gnutls_x509_crl_export
----------------------

 -- Function: int gnutls_x509_crl_export (gnutls_x509_crl_t CRL,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     CRL: Holds the revocation list

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a private key PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the revocation list to DER or PEM format.

     If the buffer provided is not long enough to hold the output, then
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     X509 CRL".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. and a negative error code on
     failure.

gnutls_x509_crl_get_authority_key_gn_serial
-------------------------------------------

 -- Function: int gnutls_x509_crl_get_authority_key_gn_serial
          (gnutls_x509_crl_t CRL, unsigned int SEQ, void * ALT, size_t
          * ALT_SIZE, unsigned int * ALT_TYPE, void* SERIAL, size_t *
          SERIAL_SIZE, unsigned int * CRITICAL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     ALT: is the place where the alternative name will be copied to

     ALT_SIZE: holds the size of alt.

     ALT_TYPE: holds the type of the alternative name (one of
     gnutls_x509_subject_alt_name_t).

     SERIAL: buffer to store the serial number (may be null)

     SERIAL_SIZE: Holds the size of the serial field (may be null)

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the X.509 authority key identifier when
     stored as a general name (authorityCertIssuer) and serial number.

     Because more than one general names might be stored  `seq' can be
     used as a counter to request them all until
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Returns:* Returns 0 on success, or an error code.

     *Since:* 3.0

gnutls_x509_crl_get_authority_key_id
------------------------------------

 -- Function: int gnutls_x509_crl_get_authority_key_id
          (gnutls_x509_crl_t CRL, void * ID, size_t * ID_SIZE, unsigned
          int * CRITICAL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     ID: The place where the identifier will be copied

     ID_SIZE: Holds the size of the result field.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the CRL authority's key identifier.  This
     is obtained by the X.509 Authority Key identifier extension field
     (2.5.29.35).  Note that this function only returns the
     keyIdentifier field of the extension and
     `GNUTLS_E_X509_UNSUPPORTED_EXTENSION' , if the extension contains
     the name and serial number of the certificate. In that case
     `gnutls_x509_crl_get_authority_key_gn_serial()'  may be used.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.

     *Since:* 2.8.0

gnutls_x509_crl_get_crt_count
-----------------------------

 -- Function: int gnutls_x509_crl_get_crt_count (gnutls_x509_crl_t CRL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     This function will return the number of revoked certificates in the
     given CRL.

     *Returns:* number of certificates, a negative error code on
     failure.

gnutls_x509_crl_get_crt_serial
------------------------------

 -- Function: int gnutls_x509_crl_get_crt_serial (gnutls_x509_crl_t
          CRL, int INDX, unsigned char * SERIAL, size_t * SERIAL_SIZE,
          time_t * T)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     INDX: the index of the certificate to extract (starting from 0)

     SERIAL: where the serial number will be copied

     SERIAL_SIZE: initially holds the size of serial

     T: if non null, will hold the time this certificate was revoked

     This function will retrieve the serial number of the specified, by
     the index, revoked certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. and a negative error code on
     error.

gnutls_x509_crl_get_dn_oid
--------------------------

 -- Function: int gnutls_x509_crl_get_dn_oid (gnutls_x509_crl_t CRL,
          int INDX, void * OID, size_t * SIZEOF_OID)
     CRL: should contain a gnutls_x509_crl_t structure

     INDX: Specifies which DN OID to send. Use (0) to get the first one.

     OID: a pointer to a structure to hold the name (may be null)

     SIZEOF_OID: initially holds the size of 'oid'

     This function will extract the requested OID of the name of the CRL
     issuer, specified by the given index.

     If oid is null then only the size will be filled.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the sizeof_oid will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crl_get_extension_data
----------------------------------

 -- Function: int gnutls_x509_crl_get_extension_data (gnutls_x509_crl_t
          CRL, int INDX, void * DATA, size_t * SIZEOF_DATA)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     DATA: a pointer to a structure to hold the data (may be null)

     SIZEOF_DATA: initially holds the size of  `oid'

     This function will return the requested extension data in the CRL.
     The extension data will be stored as a string in the provided
     buffer.

     Use `gnutls_x509_crl_get_extension_info()'  to extract the OID and
     critical flag.  Use `gnutls_x509_crl_get_extension_info()'
     instead, if you want to get data indexed by the extension OID
     rather than sequence.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crl_get_extension_info
----------------------------------

 -- Function: int gnutls_x509_crl_get_extension_info (gnutls_x509_crl_t
          CRL, int INDX, void * OID, size_t * SIZEOF_OID, unsigned int
          * CRITICAL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     INDX: Specifies which extension OID to send, use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID

     SIZEOF_OID: initially holds the maximum size of  `oid' , on return
     holds actual size of  `oid' .

     CRITICAL: output variable with critical flag, may be NULL.

     This function will return the requested extension OID in the CRL,
     and the critical flag for it.  The extension OID will be stored as
     a string in the provided buffer.  Use
     `gnutls_x509_crl_get_extension_data()'  to extract the data.

     If the buffer provided is not long enough to hold the output, then
     * `sizeof_oid' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'  will
     be returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crl_get_extension_oid
---------------------------------

 -- Function: int gnutls_x509_crl_get_extension_oid (gnutls_x509_crl_t
          CRL, int INDX, void * OID, size_t * SIZEOF_OID)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     INDX: Specifies which extension OID to send, use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID (may be null)

     SIZEOF_OID: initially holds the size of  `oid'

     This function will return the requested extension OID in the CRL.
     The extension OID will be stored as a string in the provided
     buffer.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crl_get_issuer_dn
-----------------------------

 -- Function: int gnutls_x509_crl_get_issuer_dn (const
          gnutls_x509_crl_t CRL, char * BUF, size_t * SIZEOF_BUF)
     CRL: should contain a gnutls_x509_crl_t structure

     BUF: a pointer to a structure to hold the peer's name (may be null)

     SIZEOF_BUF: initially holds the size of  `buf'

     This function will copy the name of the CRL issuer in the provided
     buffer. The name will be in the form "C=xxxx,O=yyyy,CN=zzzz" as
     described in RFC4514. The output string will be ASCII or UTF-8
     encoded, depending on the certificate data.

     If buf is `NULL'  then only the size will be filled.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the sizeof_buf will be updated
     with the required size, and 0 on success.

gnutls_x509_crl_get_issuer_dn_by_oid
------------------------------------

 -- Function: int gnutls_x509_crl_get_issuer_dn_by_oid
          (gnutls_x509_crl_t CRL, const char * OID, int INDX, unsigned
          int RAW_FLAG, void * BUF, size_t * SIZEOF_BUF)
     CRL: should contain a gnutls_x509_crl_t structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the RDN, this specifies
     which to send. Use (0) to get the first one.

     RAW_FLAG: If non (0) returns the raw DER data of the DN part.

     BUF: a pointer to a structure to hold the peer's name (may be null)

     SIZEOF_BUF: initially holds the size of  `buf'

     This function will extract the part of the name of the CRL issuer
     specified by the given OID. The output will be encoded as described
     in RFC4514. The output string will be ASCII or UTF-8 encoded,
     depending on the certificate data.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     If raw flag is (0), this function will only return known OIDs as
     text. Other OIDs will be DER encoded, as described in RFC4514 - in
     hex format with a '#' prefix.  You can check about known OIDs
     using `gnutls_x509_dn_oid_known()' .

     If buf is null then only the size will be filled.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the sizeof_buf will be updated
     with the required size, and 0 on success.

gnutls_x509_crl_get_next_update
-------------------------------

 -- Function: time_t gnutls_x509_crl_get_next_update (gnutls_x509_crl_t
          CRL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     This function will return the time the next CRL will be issued.
     This field is optional in a CRL so it might be normal to get an
     error instead.

     *Returns:* when the next CRL will be issued, or (time_t)-1 on
     error.

gnutls_x509_crl_get_number
--------------------------

 -- Function: int gnutls_x509_crl_get_number (gnutls_x509_crl_t CRL,
          void * RET, size_t * RET_SIZE, unsigned int * CRITICAL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     RET: The place where the number will be copied

     RET_SIZE: Holds the size of the result field.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the CRL number extension.  This is
     obtained by the CRL Number extension field (2.5.29.20).

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.

     *Since:* 2.8.0

gnutls_x509_crl_get_raw_issuer_dn
---------------------------------

 -- Function: int gnutls_x509_crl_get_raw_issuer_dn (gnutls_x509_crl_t
          CRL, gnutls_datum_t * DN)
     CRL: should contain a gnutls_x509_crl_t structure

     DN: will hold the starting point of the DN

     This function will return a pointer to the DER encoded DN structure
     and the length.

     *Returns:* a negative error code on error, and (0) on success.

     *Since:* 2.12.0

gnutls_x509_crl_get_signature
-----------------------------

 -- Function: int gnutls_x509_crl_get_signature (gnutls_x509_crl_t CRL,
          char * SIG, size_t * SIZEOF_SIG)
     CRL: should contain a gnutls_x509_crl_t structure

     SIG: a pointer where the signature part will be copied (may be
     null).

     SIZEOF_SIG: initially holds the size of  `sig'

     This function will extract the signature field of a CRL.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. and a negative error code on
     error.

gnutls_x509_crl_get_signature_algorithm
---------------------------------------

 -- Function: int gnutls_x509_crl_get_signature_algorithm
          (gnutls_x509_crl_t CRL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     This function will return a value of the `gnutls_sign_algorithm_t'
     enumeration that is the signature algorithm.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_get_this_update
-------------------------------

 -- Function: time_t gnutls_x509_crl_get_this_update (gnutls_x509_crl_t
          CRL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     This function will return the time this CRL was issued.

     *Returns:* when the CRL was issued, or (time_t)-1 on error.

gnutls_x509_crl_get_version
---------------------------

 -- Function: int gnutls_x509_crl_get_version (gnutls_x509_crl_t CRL)
     CRL: should contain a `gnutls_x509_crl_t'  structure

     This function will return the version of the specified CRL.

     *Returns:* The version number, or a negative error code on error.

gnutls_x509_crl_import
----------------------

 -- Function: int gnutls_x509_crl_import (gnutls_x509_crl_t CRL, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT)
     CRL: The structure to store the parsed CRL.

     DATA: The DER or PEM encoded CRL.

     FORMAT: One of DER or PEM

     This function will convert the given DER or PEM encoded CRL to the
     native `gnutls_x509_crl_t'  format. The output will be stored in
     'crl'.

     If the CRL is PEM encoded it should have a header of "X509 CRL".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_init
--------------------

 -- Function: int gnutls_x509_crl_init (gnutls_x509_crl_t * CRL)
     CRL: The structure to be initialized

     This function will initialize a CRL structure. CRL stands for
     Certificate Revocation List. A revocation list usually contains
     lists of certificate serial numbers that have been revoked by an
     Authority. The revocation lists are always signed with the
     authority's private key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_list_import
---------------------------

 -- Function: int gnutls_x509_crl_list_import (gnutls_x509_crl_t *
          CRLS, unsigned int * CRL_MAX, const gnutls_datum_t * DATA,
          gnutls_x509_crt_fmt_t FORMAT, unsigned int FLAGS)
     CRLS: The structures to store the parsed CRLs. Must not be
     initialized.

     CRL_MAX: Initially must hold the maximum number of crls. It will
     be updated with the number of crls available.

     DATA: The PEM encoded CRLs

     FORMAT: One of DER or PEM.

     FLAGS: must be (0) or an OR'd sequence of
     gnutls_certificate_import_flags.

     This function will convert the given PEM encoded CRL list to the
     native gnutls_x509_crl_t format. The output will be stored in
     `crls' .  They will be automatically initialized.

     If the Certificate is PEM encoded it should have a header of "X509
     CRL".

     *Returns:* the number of certificates read or a negative error
     value.

     *Since:* 3.0

gnutls_x509_crl_list_import2
----------------------------

 -- Function: int gnutls_x509_crl_list_import2 (gnutls_x509_crl_t **
          CRLS, unsigned int * SIZE, const gnutls_datum_t * DATA,
          gnutls_x509_crt_fmt_t FORMAT, unsigned int FLAGS)
     CRLS: The structures to store the parsed crl list. Must not be
     initialized.

     SIZE: It will contain the size of the list.

     DATA: The PEM encoded CRL.

     FORMAT: One of DER or PEM.

     FLAGS: must be (0) or an OR'd sequence of
     gnutls_certificate_import_flags.

     This function will convert the given PEM encoded CRL list to the
     native gnutls_x509_crl_t format. The output will be stored in
     `crls' .  They will be automatically initialized.

     If the Certificate is PEM encoded it should have a header of "X509
     CRL".

     *Returns:* the number of certificates read or a negative error
     value.

     *Since:* 3.0

gnutls_x509_crl_print
---------------------

 -- Function: int gnutls_x509_crl_print (gnutls_x509_crl_t CRL,
          gnutls_certificate_print_formats_t FORMAT, gnutls_datum_t *
          OUT)
     CRL: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print a X.509 certificate revocation
     list, suitable for display to a human.

     The output  `out' needs to be deallocate using `gnutls_free()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_set_authority_key_id
------------------------------------

 -- Function: int gnutls_x509_crl_set_authority_key_id
          (gnutls_x509_crl_t CRL, const void * ID, size_t ID_SIZE)
     CRL: a CRL of type `gnutls_x509_crl_t'

     ID: The key ID

     ID_SIZE: Holds the size of the serial field.

     This function will set the CRL's authority key ID extension.  Only
     the keyIdentifier field can be set with this function. This may be
     used by an authority that holds multiple private keys, to
     distinguish the used key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crl_set_crt
-----------------------

 -- Function: int gnutls_x509_crl_set_crt (gnutls_x509_crl_t CRL,
          gnutls_x509_crt_t CRT, time_t REVOCATION_TIME)
     CRL: should contain a gnutls_x509_crl_t structure

     CRT: a certificate of type `gnutls_x509_crt_t'  with the revoked
     certificate

     REVOCATION_TIME: The time this certificate was revoked

     This function will set a revoked certificate's serial number to
     the CRL.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_set_crt_serial
------------------------------

 -- Function: int gnutls_x509_crl_set_crt_serial (gnutls_x509_crl_t
          CRL, const void * SERIAL, size_t SERIAL_SIZE, time_t
          REVOCATION_TIME)
     CRL: should contain a gnutls_x509_crl_t structure

     SERIAL: The revoked certificate's serial number

     SERIAL_SIZE: Holds the size of the serial field.

     REVOCATION_TIME: The time this certificate was revoked

     This function will set a revoked certificate's serial number to
     the CRL.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_set_next_update
-------------------------------

 -- Function: int gnutls_x509_crl_set_next_update (gnutls_x509_crl_t
          CRL, time_t EXP_TIME)
     CRL: should contain a gnutls_x509_crl_t structure

     EXP_TIME: The actual time

     This function will set the time this CRL will be updated.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_set_number
--------------------------

 -- Function: int gnutls_x509_crl_set_number (gnutls_x509_crl_t CRL,
          const void * NR, size_t NR_SIZE)
     CRL: a CRL of type `gnutls_x509_crl_t'

     NR: The CRL number

     NR_SIZE: Holds the size of the nr field.

     This function will set the CRL's number extension. This is to be
     used as a unique and monotonic number assigned to the CRL by the
     authority.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crl_set_this_update
-------------------------------

 -- Function: int gnutls_x509_crl_set_this_update (gnutls_x509_crl_t
          CRL, time_t ACT_TIME)
     CRL: should contain a gnutls_x509_crl_t structure

     ACT_TIME: The actual time

     This function will set the time this CRL was issued.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_set_version
---------------------------

 -- Function: int gnutls_x509_crl_set_version (gnutls_x509_crl_t CRL,
          unsigned int VERSION)
     CRL: should contain a gnutls_x509_crl_t structure

     VERSION: holds the version number. For CRLv1 crls must be 1.

     This function will set the version of the CRL. This must be one
     for CRL version 1, and so on. The CRLs generated by gnutls should
     have a version number of 2.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_sign2
---------------------

 -- Function: int gnutls_x509_crl_sign2 (gnutls_x509_crl_t CRL,
          gnutls_x509_crt_t ISSUER, gnutls_x509_privkey_t ISSUER_KEY,
          gnutls_digest_algorithm_t DIG, unsigned int FLAGS)
     CRL: should contain a gnutls_x509_crl_t structure

     ISSUER: is the certificate of the certificate issuer

     ISSUER_KEY: holds the issuer's private key

     DIG: The message digest to use. GNUTLS_DIG_SHA1 is the safe choice
     unless you know what you're doing.

     FLAGS: must be 0

     This function will sign the CRL with the issuer's private key, and
     will copy the issuer's information into the CRL.

     This must be the last step in a certificate CRL since all the
     previously set parameters are now signed.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crl_verify
----------------------

 -- Function: int gnutls_x509_crl_verify (gnutls_x509_crl_t CRL, const
          gnutls_x509_crt_t * CA_LIST, int CA_LIST_LENGTH, unsigned int
          FLAGS, unsigned int * VERIFY)
     CRL: is the crl to be verified

     CA_LIST: is a certificate list that is considered to be trusted one

     CA_LIST_LENGTH: holds the number of CA certificates in CA_list

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     VERIFY: will hold the crl verification output.

     This function will try to verify the given crl and return its
     status.  See `gnutls_x509_crt_list_verify()'  for a detailed
     description of return values.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_deinit
----------------------

 -- Function: void gnutls_x509_crq_deinit (gnutls_x509_crq_t CRQ)
     CRQ: The structure to be initialized

     This function will deinitialize a PKCS`10'  certificate request
     structure.

gnutls_x509_crq_export
----------------------

 -- Function: int gnutls_x509_crq_export (gnutls_x509_crq_t CRQ,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a certificate request PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the certificate request to a PEM or DER
     encoded PKCS10 structure.

     If the buffer provided is not long enough to hold the output, then
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  will be returned and *
     `output_data_size' will be updated.

     If the structure is PEM encoded, it will have a header of "BEGIN
     NEW CERTIFICATE REQUEST".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_get_attribute_by_oid
------------------------------------

 -- Function: int gnutls_x509_crq_get_attribute_by_oid
          (gnutls_x509_crq_t CRQ, const char * OID, int INDX, void *
          BUF, size_t * SIZEOF_BUF)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     OID: holds an Object Identified in (0)-terminated string

     INDX: In case multiple same OIDs exist in the attribute list, this
     specifies which to send, use (0) to get the first one

     BUF: a pointer to a structure to hold the attribute data (may be
     `NULL' )

     SIZEOF_BUF: initially holds the size of  `buf'

     This function will return the attribute in the certificate request
     specified by the given Object ID.  The attribute will be DER
     encoded.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_get_attribute_data
----------------------------------

 -- Function: int gnutls_x509_crq_get_attribute_data (gnutls_x509_crq_t
          CRQ, int INDX, void * DATA, size_t * SIZEOF_DATA)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     INDX: Specifies which attribute OID to send. Use (0) to get the
     first one.

     DATA: a pointer to a structure to hold the data (may be null)

     SIZEOF_DATA: initially holds the size of  `oid'

     This function will return the requested attribute data in the
     certificate request.  The attribute data will be stored as a
     string in the provided buffer.

     Use `gnutls_x509_crq_get_attribute_info()'  to extract the OID.
     Use `gnutls_x509_crq_get_attribute_by_oid()'  instead, if you want
     to get data indexed by the attribute OID rather than sequence.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_attribute_info
----------------------------------

 -- Function: int gnutls_x509_crq_get_attribute_info (gnutls_x509_crq_t
          CRQ, int INDX, void * OID, size_t * SIZEOF_OID)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     INDX: Specifies which attribute OID to send. Use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID

     SIZEOF_OID: initially holds the maximum size of  `oid' , on return
     holds actual size of  `oid' .

     This function will return the requested attribute OID in the
     certificate, and the critical flag for it.  The attribute OID will
     be stored as a string in the provided buffer.  Use
     `gnutls_x509_crq_get_attribute_data()'  to extract the data.

     If the buffer provided is not long enough to hold the output, then
     * `sizeof_oid' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'  will
     be returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_basic_constraints
-------------------------------------

 -- Function: int gnutls_x509_crq_get_basic_constraints
          (gnutls_x509_crq_t CRQ, unsigned int * CRITICAL, unsigned int
          * CA, int * PATHLEN)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     CRITICAL: will be non (0) if the extension is marked as critical

     CA: pointer to output integer indicating CA status, may be NULL,
     value is 1 if the certificate CA flag is set, 0 otherwise.

     PATHLEN: pointer to output integer indicating path length (may be
     NULL), non-negative error codes indicate a present
     pathLenConstraint field and the actual value, -1 indicate that the
     field is absent.

     This function will read the certificate's basic constraints, and
     return the certificates CA status.  It reads the basicConstraints
     X.509 extension (2.5.29.19).

     *Returns:* If the certificate is a CA a positive value will be
     returned, or (0) if the certificate does not have CA flag set.  A
     negative error code may be returned in case of errors.  If the
     certificate does not contain the basicConstraints extension
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_challenge_password
--------------------------------------

 -- Function: int gnutls_x509_crq_get_challenge_password
          (gnutls_x509_crq_t CRQ, char * PASS, size_t * SIZEOF_PASS)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     PASS: will hold a (0)-terminated password string

     SIZEOF_PASS: Initially holds the size of  `pass' .

     This function will return the challenge password in the request.
     The challenge password is intended to be used for requesting a
     revocation of the certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_get_dn
----------------------

 -- Function: int gnutls_x509_crq_get_dn (gnutls_x509_crq_t CRQ, char *
          BUF, size_t * SIZEOF_BUF)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     BUF: a pointer to a structure to hold the name (may be `NULL' )

     SIZEOF_BUF: initially holds the size of  `buf'

     This function will copy the name of the Certificate request subject
     to the provided buffer.  The name will be in the form
     "C=xxxx,O=yyyy,CN=zzzz" as described in RFC 2253. The output string
     `buf' will be ASCII or UTF-8 encoded, depending on the certificate
     data.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the * `sizeof_buf' will be
     updated with the required size.  On success 0 is returned.

gnutls_x509_crq_get_dn_by_oid
-----------------------------

 -- Function: int gnutls_x509_crq_get_dn_by_oid (gnutls_x509_crq_t CRQ,
          const char * OID, int INDX, unsigned int RAW_FLAG, void *
          BUF, size_t * SIZEOF_BUF)
     CRQ: should contain a gnutls_x509_crq_t structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the RDN, this specifies
     which to send. Use (0) to get the first one.

     RAW_FLAG: If non (0) returns the raw DER data of the DN part.

     BUF: a pointer to a structure to hold the name (may be `NULL' )

     SIZEOF_BUF: initially holds the size of  `buf'

     This function will extract the part of the name of the Certificate
     request subject, specified by the given OID. The output will be
     encoded as described in RFC2253. The output string will be ASCII
     or UTF-8 encoded, depending on the certificate data.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     If raw flag is (0), this function will only return known OIDs as
     text. Other OIDs will be DER encoded, as described in RFC2253 - in
     hex format with a '\#' prefix.  You can check about known OIDs
     using `gnutls_x509_dn_oid_known()' .

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the * `sizeof_buf' will be
     updated with the required size.  On success 0 is returned.

gnutls_x509_crq_get_dn_oid
--------------------------

 -- Function: int gnutls_x509_crq_get_dn_oid (gnutls_x509_crq_t CRQ,
          int INDX, void * OID, size_t * SIZEOF_OID)
     CRQ: should contain a gnutls_x509_crq_t structure

     INDX: Specifies which DN OID to send. Use (0) to get the first one.

     OID: a pointer to a structure to hold the name (may be `NULL' )

     SIZEOF_OID: initially holds the size of  `oid'

     This function will extract the requested OID of the name of the
     certificate request subject, specified by the given index.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the * `sizeof_oid' will be
     updated with the required size.  On success 0 is returned.

gnutls_x509_crq_get_extension_by_oid
------------------------------------

 -- Function: int gnutls_x509_crq_get_extension_by_oid
          (gnutls_x509_crq_t CRQ, const char * OID, int INDX, void *
          BUF, size_t * SIZEOF_BUF, unsigned int * CRITICAL)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the extensions, this
     specifies which to send. Use (0) to get the first one.

     BUF: a pointer to a structure to hold the name (may be null)

     SIZEOF_BUF: initially holds the size of  `buf'

     CRITICAL: will be non (0) if the extension is marked as critical

     This function will return the extension specified by the OID in
     the certificate.  The extensions will be returned as binary data
     DER encoded, in the provided buffer.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If the
     certificate does not contain the specified extension
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_extension_data
----------------------------------

 -- Function: int gnutls_x509_crq_get_extension_data (gnutls_x509_crq_t
          CRQ, int INDX, void * DATA, size_t * SIZEOF_DATA)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     DATA: a pointer to a structure to hold the data (may be null)

     SIZEOF_DATA: initially holds the size of  `oid'

     This function will return the requested extension data in the
     certificate.  The extension data will be stored as a string in the
     provided buffer.

     Use `gnutls_x509_crq_get_extension_info()'  to extract the OID and
     critical flag.  Use `gnutls_x509_crq_get_extension_by_oid()'
     instead, if you want to get data indexed by the extension OID
     rather than sequence.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_extension_info
----------------------------------

 -- Function: int gnutls_x509_crq_get_extension_info (gnutls_x509_crq_t
          CRQ, int INDX, void * OID, size_t * SIZEOF_OID, unsigned int
          * CRITICAL)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID

     SIZEOF_OID: initially holds the maximum size of  `oid' , on return
     holds actual size of  `oid' .

     CRITICAL: output variable with critical flag, may be NULL.

     This function will return the requested extension OID in the
     certificate, and the critical flag for it.  The extension OID will
     be stored as a string in the provided buffer.  Use
     `gnutls_x509_crq_get_extension_data()'  to extract the data.

     If the buffer provided is not long enough to hold the output, then
     * `sizeof_oid' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'  will
     be returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code in case of an error.  If your have
     reached the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_key_id
--------------------------

 -- Function: int gnutls_x509_crq_get_key_id (gnutls_x509_crq_t CRQ,
          unsigned int FLAGS, unsigned char * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     CRQ: a certificate of type `gnutls_x509_crq_t'

     FLAGS: should be 0 for now

     OUTPUT_DATA: will contain the key ID

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will return a unique ID the depends on the public key
     parameters.  This ID can be used in checking whether a certificate
     corresponds to the given private key.

     If the buffer provided is not long enough to hold the output, then
     * `output_data_size' is updated and GNUTLS_E_SHORT_MEMORY_BUFFER
     will be returned.  The output will normally be a SHA-1 hash output,
     which is 20 bytes.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

     *Since:* 2.8.0

gnutls_x509_crq_get_key_purpose_oid
-----------------------------------

 -- Function: int gnutls_x509_crq_get_key_purpose_oid
          (gnutls_x509_crq_t CRQ, int INDX, void * OID, size_t *
          SIZEOF_OID, unsigned int * CRITICAL)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     INDX: This specifies which OID to return, use (0) to get the first
     one

     OID: a pointer to a buffer to hold the OID (may be `NULL' )

     SIZEOF_OID: initially holds the size of  `oid'

     CRITICAL: output variable with critical flag, may be `NULL' .

     This function will extract the key purpose OIDs of the Certificate
     specified by the given index.  These are stored in the Extended Key
     Usage extension (2.5.29.37).  See the GNUTLS_KP_* definitions for
     human readable names.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the * `sizeof_oid' will be
     updated with the required size.  On success 0 is returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_key_rsa_raw
-------------------------------

 -- Function: int gnutls_x509_crq_get_key_rsa_raw (gnutls_x509_crq_t
          CRQ, gnutls_datum_t * M, gnutls_datum_t * E)
     CRQ: Holds the certificate

     M: will hold the modulus

     E: will hold the public exponent

     This function will export the RSA public key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_get_key_usage
-----------------------------

 -- Function: int gnutls_x509_crq_get_key_usage (gnutls_x509_crq_t CRQ,
          unsigned int * KEY_USAGE, unsigned int * CRITICAL)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     KEY_USAGE: where the key usage bits will be stored

     CRITICAL: will be non (0) if the extension is marked as critical

     This function will return certificate's key usage, by reading the
     keyUsage X.509 extension (2.5.29.15).  The key usage value will
     ORed values of the: `GNUTLS_KEY_DIGITAL_SIGNATURE' ,
     `GNUTLS_KEY_NON_REPUDIATION' , `GNUTLS_KEY_KEY_ENCIPHERMENT' ,
     `GNUTLS_KEY_DATA_ENCIPHERMENT' , `GNUTLS_KEY_KEY_AGREEMENT' ,
     `GNUTLS_KEY_KEY_CERT_SIGN' , `GNUTLS_KEY_CRL_SIGN' ,
     `GNUTLS_KEY_ENCIPHER_ONLY' , `GNUTLS_KEY_DECIPHER_ONLY' .

     *Returns:* the certificate key usage, or a negative error code in
     case of parsing error.  If the certificate does not contain the
     keyUsage extension `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be
     returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_pk_algorithm
--------------------------------

 -- Function: int gnutls_x509_crq_get_pk_algorithm (gnutls_x509_crq_t
          CRQ, unsigned int * BITS)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     BITS: if bits is non-`NULL'  it will hold the size of the
     parameters' in bits

     This function will return the public key algorithm of a PKCS`10'
     certificate request.

     If bits is non-`NULL' , it should have enough size to hold the
     parameters size in bits.  For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

gnutls_x509_crq_get_private_key_usage_period
--------------------------------------------

 -- Function: int gnutls_x509_crq_get_private_key_usage_period
          (gnutls_x509_crq_t CRQ, time_t* ACTIVATION, time_t*
          EXPIRATION, unsigned int * CRITICAL)
     CRQ: - undescribed -

     ACTIVATION: The activation time

     EXPIRATION: The expiration time

     CRITICAL: the extension status

     This function will return the expiration and activation times of
     the private key of the certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' if the extension is not
     present, otherwise a negative error value.

gnutls_x509_crq_get_subject_alt_name
------------------------------------

 -- Function: int gnutls_x509_crq_get_subject_alt_name
          (gnutls_x509_crq_t CRQ, unsigned int SEQ, void * RET, size_t
          * RET_SIZE, unsigned int * RET_TYPE, unsigned int * CRITICAL)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     SEQ: specifies the sequence number of the alt name, 0 for the
     first one, 1 for the second etc.

     RET: is the place where the alternative name will be copied to

     RET_SIZE: holds the size of ret.

     RET_TYPE: holds the `gnutls_x509_subject_alt_name_t'  name type

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the alternative names, contained in the
     given certificate.  It is the same as
     `gnutls_x509_crq_get_subject_alt_name()'  except for the fact that
     it will return the type of the alternative name in  `ret_type'
     even if the function fails for some reason (i.e.  the buffer
     provided is not enough).

     *Returns:* the alternative subject name type on success, one of the
     enumerated `gnutls_x509_subject_alt_name_t' .  It will return
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  if  `ret_size' is not large enough
     to hold the value.  In that case  `ret_size' will be updated with
     the required size.  If the certificate request does not have an
     Alternative name with the specified sequence number then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_subject_alt_othername_oid
---------------------------------------------

 -- Function: int gnutls_x509_crq_get_subject_alt_othername_oid
          (gnutls_x509_crq_t CRQ, unsigned int SEQ, void * RET, size_t
          * RET_SIZE)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     RET: is the place where the otherName OID will be copied to

     RET_SIZE: holds the size of ret.

     This function will extract the type OID of an otherName Subject
     Alternative Name, contained in the given certificate, and return
     the type as an enumerated element.

     This function is only useful if
     `gnutls_x509_crq_get_subject_alt_name()'  returned
     `GNUTLS_SAN_OTHERNAME' .

     *Returns:* the alternative subject name type on success, one of the
     enumerated gnutls_x509_subject_alt_name_t.  For supported OIDs, it
     will return one of the virtual (GNUTLS_SAN_OTHERNAME_*) types,
     e.g. `GNUTLS_SAN_OTHERNAME_XMPP' , and `GNUTLS_SAN_OTHERNAME'  for
     unknown OIDs.  It will return `GNUTLS_E_SHORT_MEMORY_BUFFER'  if
     `ret_size' is not large enough to hold the value.  In that case
     `ret_size' will be updated with the required size.  If the
     certificate does not have an Alternative name with the specified
     sequence number and with the otherName type then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Since:* 2.8.0

gnutls_x509_crq_get_version
---------------------------

 -- Function: int gnutls_x509_crq_get_version (gnutls_x509_crq_t CRQ)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     This function will return the version of the specified Certificate
     request.

     *Returns:* version of certificate request, or a negative error
     code on error.

gnutls_x509_crq_import
----------------------

 -- Function: int gnutls_x509_crq_import (gnutls_x509_crq_t CRQ, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT)
     CRQ: The structure to store the parsed certificate request.

     DATA: The DER or PEM encoded certificate.

     FORMAT: One of DER or PEM

     This function will convert the given DER or PEM encoded certificate
     request to a `gnutls_x509_crq_t'  structure.  The output will be
     stored in  `crq' .

     If the Certificate is PEM encoded it should have a header of "NEW
     CERTIFICATE REQUEST".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_init
--------------------

 -- Function: int gnutls_x509_crq_init (gnutls_x509_crq_t * CRQ)
     CRQ: The structure to be initialized

     This function will initialize a PKCS`10'  certificate request
     structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_print
---------------------

 -- Function: int gnutls_x509_crq_print (gnutls_x509_crq_t CRQ,
          gnutls_certificate_print_formats_t FORMAT, gnutls_datum_t *
          OUT)
     CRQ: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print a certificate request, suitable for
     display to a human.

     The output  `out' needs to be deallocate using `gnutls_free()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_set_attribute_by_oid
------------------------------------

 -- Function: int gnutls_x509_crq_set_attribute_by_oid
          (gnutls_x509_crq_t CRQ, const char * OID, void * BUF, size_t
          SIZEOF_BUF)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     OID: holds an Object Identified in (0)-terminated string

     BUF: a pointer to a structure that holds the attribute data

     SIZEOF_BUF: holds the size of  `buf'

     This function will set the attribute in the certificate request
     specified by the given Object ID.  The attribute must be be DER
     encoded.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_set_basic_constraints
-------------------------------------

 -- Function: int gnutls_x509_crq_set_basic_constraints
          (gnutls_x509_crq_t CRQ, unsigned int CA, int
          PATHLENCONSTRAINT)
     CRQ: a certificate request of type `gnutls_x509_crq_t'

     CA: true(1) or false(0) depending on the Certificate authority
     status.

     PATHLENCONSTRAINT: non-negative error codes indicate maximum
     length of path, and negative error codes indicate that the
     pathLenConstraints field should not be present.

     This function will set the basicConstraints certificate extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_set_challenge_password
--------------------------------------

 -- Function: int gnutls_x509_crq_set_challenge_password
          (gnutls_x509_crq_t CRQ, const char * PASS)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     PASS: holds a (0)-terminated password

     This function will set a challenge password to be used when
     revoking the request.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_set_dn_by_oid
-----------------------------

 -- Function: int gnutls_x509_crq_set_dn_by_oid (gnutls_x509_crq_t CRQ,
          const char * OID, unsigned int RAW_FLAG, const void * DATA,
          unsigned int SIZEOF_DATA)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     OID: holds an Object Identifier in a (0)-terminated string

     RAW_FLAG: must be 0, or 1 if the data are DER encoded

     DATA: a pointer to the input data

     SIZEOF_DATA: holds the size of  `data'

     This function will set the part of the name of the Certificate
     request subject, specified by the given OID.  The input string
     should be ASCII or UTF-8 encoded.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     With this function you can only set the known OIDs.  You can test
     for known OIDs using `gnutls_x509_dn_oid_known()' .  For OIDs that
     are not known (by gnutls) you should properly DER encode your
     data, and call this function with raw_flag set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_set_key
-----------------------

 -- Function: int gnutls_x509_crq_set_key (gnutls_x509_crq_t CRQ,
          gnutls_x509_privkey_t KEY)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     KEY: holds a private key

     This function will set the public parameters from the given private
     key to the request.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_set_key_purpose_oid
-----------------------------------

 -- Function: int gnutls_x509_crq_set_key_purpose_oid
          (gnutls_x509_crq_t CRQ, const void * OID, unsigned int
          CRITICAL)
     CRQ: a certificate of type `gnutls_x509_crq_t'

     OID: a pointer to a (0)-terminated string that holds the OID

     CRITICAL: Whether this extension will be critical or not

     This function will set the key purpose OIDs of the Certificate.
     These are stored in the Extended Key Usage extension (2.5.29.37)
     See the GNUTLS_KP_* definitions for human readable names.

     Subsequent calls to this function will append OIDs to the OID list.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_set_key_rsa_raw
-------------------------------

 -- Function: int gnutls_x509_crq_set_key_rsa_raw (gnutls_x509_crq_t
          CRQ, const gnutls_datum_t * M, const gnutls_datum_t * E)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     M: holds the modulus

     E: holds the public exponent

     This function will set the public parameters from the given private
     key to the request. Only RSA keys are currently supported.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.6.0

gnutls_x509_crq_set_key_usage
-----------------------------

 -- Function: int gnutls_x509_crq_set_key_usage (gnutls_x509_crq_t CRQ,
          unsigned int USAGE)
     CRQ: a certificate request of type `gnutls_x509_crq_t'

     USAGE: an ORed sequence of the GNUTLS_KEY_* elements.

     This function will set the keyUsage certificate extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_set_private_key_usage_period
--------------------------------------------

 -- Function: int gnutls_x509_crq_set_private_key_usage_period
          (gnutls_x509_crq_t CRQ, time_t ACTIVATION, time_t EXPIRATION)
     CRQ: a certificate of type `gnutls_x509_crq_t'

     ACTIVATION: The activation time

     EXPIRATION: The expiration time

     This function will set the private key usage period extension
     (2.5.29.16).

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_set_subject_alt_name
------------------------------------

 -- Function: int gnutls_x509_crq_set_subject_alt_name
          (gnutls_x509_crq_t CRQ, gnutls_x509_subject_alt_name_t NT,
          const void * DATA, unsigned int DATA_SIZE, unsigned int FLAGS)
     CRQ: a certificate request of type `gnutls_x509_crq_t'

     NT: is one of the `gnutls_x509_subject_alt_name_t'  enumerations

     DATA: The data to be set

     DATA_SIZE: The size of data to be set

     FLAGS: `GNUTLS_FSAN_SET'  to clear previous data or
     `GNUTLS_FSAN_APPEND'  to append.

     This function will set the subject alternative name certificate
     extension.  It can set the following types:

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crq_set_version
---------------------------

 -- Function: int gnutls_x509_crq_set_version (gnutls_x509_crq_t CRQ,
          unsigned int VERSION)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     VERSION: holds the version number, for v1 Requests must be 1

     This function will set the version of the certificate request.  For
     version 1 requests this must be one.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crq_sign2
---------------------

 -- Function: int gnutls_x509_crq_sign2 (gnutls_x509_crq_t CRQ,
          gnutls_x509_privkey_t KEY, gnutls_digest_algorithm_t DIG,
          unsigned int FLAGS)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     KEY: holds a private key

     DIG: The message digest to use, i.e., `GNUTLS_DIG_SHA1'

     FLAGS: must be 0

     This function will sign the certificate request with a private key.
     This must be the same key as the one used in
     `gnutls_x509_crt_set_key()'  since a certificate request is self
     signed.

     This must be the last step in a certificate request generation
     since all the previously set parameters are now signed.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.  `GNUTLS_E_ASN1_VALUE_NOT_FOUND'  is returned if you
     didn't set all information in the certificate request (e.g., the
     version using `gnutls_x509_crq_set_version()' ).

gnutls_x509_crq_verify
----------------------

 -- Function: int gnutls_x509_crq_verify (gnutls_x509_crq_t CRQ,
          unsigned int FLAGS)
     CRQ: is the crq to be verified

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     This function will verify self signature in the certificate
     request and return its status.

     *Returns:* In case of a verification failure
     `GNUTLS_E_PK_SIG_VERIFY_FAILED' is returned, and zero or positive
     code on success.

     Since 2.12.0

gnutls_x509_crt_check_hostname
------------------------------

 -- Function: int gnutls_x509_crt_check_hostname (gnutls_x509_crt_t
          CERT, const char * HOSTNAME)
     CERT: should contain an gnutls_x509_crt_t structure

     HOSTNAME: A null terminated string that contains a DNS name

     This function will check if the given certificate's subject matches
     the given hostname.  This is a basic implementation of the matching
     described in RFC2818 (HTTPS), which takes into account wildcards,
     and the DNSName/IPAddress subject alternative name PKIX extension.

     *Returns:* non (0) for a successful match, and (0) on failure.

gnutls_x509_crt_check_issuer
----------------------------

 -- Function: int gnutls_x509_crt_check_issuer (gnutls_x509_crt_t CERT,
          gnutls_x509_crt_t ISSUER)
     CERT: is the certificate to be checked

     ISSUER: is the certificate of a possible issuer

     This function will check if the given certificate was issued by the
     given issuer.

     *Returns:* It will return true (1) if the given certificate is
     issued by the given issuer, and false (0) if not.  A negative
     error code is returned in case of an error.

gnutls_x509_crt_check_revocation
--------------------------------

 -- Function: int gnutls_x509_crt_check_revocation (gnutls_x509_crt_t
          CERT, const gnutls_x509_crl_t * CRL_LIST, int CRL_LIST_LENGTH)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     CRL_LIST: should contain a list of gnutls_x509_crl_t structures

     CRL_LIST_LENGTH: the length of the crl_list

     This function will return check if the given certificate is
     revoked.  It is assumed that the CRLs have been verified before.

     *Returns:* 0 if the certificate is NOT revoked, and 1 if it is.  A
     negative error code is returned on error.

gnutls_x509_crt_cpy_crl_dist_points
-----------------------------------

 -- Function: int gnutls_x509_crt_cpy_crl_dist_points
          (gnutls_x509_crt_t DST, gnutls_x509_crt_t SRC)
     DST: a certificate of type `gnutls_x509_crt_t'

     SRC: the certificate where the dist points will be copied from

     This function will copy the CRL distribution points certificate
     extension, from the source to the destination certificate.  This
     may be useful to copy from a CA certificate to issued ones.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_deinit
----------------------

 -- Function: void gnutls_x509_crt_deinit (gnutls_x509_crt_t CERT)
     CERT: The structure to be deinitialized

     This function will deinitialize a certificate structure.

gnutls_x509_crt_export
----------------------

 -- Function: int gnutls_x509_crt_export (gnutls_x509_crt_t CERT,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     CERT: Holds the certificate

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a certificate PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the certificate to DER or PEM format.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
     be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     CERTIFICATE".

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_x509_crt_get_activation_time
-----------------------------------

 -- Function: time_t gnutls_x509_crt_get_activation_time
          (gnutls_x509_crt_t CERT)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     This function will return the time this Certificate was or will be
     activated.

     *Returns:* activation time, or (time_t)-1 on error.

gnutls_x509_crt_get_authority_info_access
-----------------------------------------

 -- Function: int gnutls_x509_crt_get_authority_info_access
          (gnutls_x509_crt_t CRT, unsigned int SEQ, int WHAT,
          gnutls_datum_t * DATA, unsigned int * CRITICAL)
     CRT: Holds the certificate

     SEQ: specifies the sequence number of the access descriptor (0 for
     the first one, 1 for the second etc.)

     WHAT: what data to get, a `gnutls_info_access_what_t'  type.

     DATA: output data to be freed with `gnutls_free()' .

     CRITICAL: pointer to output integer that is set to non-0 if the
     extension is marked as critical (may be `NULL' )

     This function extracts the Authority Information Access (AIA)
     extension, see RFC 5280 section 4.2.2.1 for more information.  The
     AIA extension holds a sequence of AccessDescription (AD) data:

     <informalexample><programlisting> AuthorityInfoAccessSyntax  ::=
     SEQUENCE SIZE (1..MAX) OF AccessDescription

     AccessDescription  ::=  SEQUENCE { accessMethod          OBJECT
     IDENTIFIER, accessLocation        GeneralName  }
     </programlisting></informalexample>

     The  `seq' input parameter is used to indicate which member of the
     sequence the caller is interested in.  The first member is 0, the
     second member 1 and so on.  When the  `seq' value is out of bounds,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     The type of data returned in  `data' is specified via  `what' which
     should be `gnutls_info_access_what_t'  values.

     If  `what' is `GNUTLS_IA_ACCESSMETHOD_OID'  then  `data' will hold
     the accessMethod OID (e.g., "1.3.6.1.5.5.7.48.1").

     If  `what' is `GNUTLS_IA_ACCESSLOCATION_GENERALNAME_TYPE' ,
     `data' will hold the accessLocation GeneralName type (e.g.,
     "uniformResourceIdentifier").

     If  `what' is `GNUTLS_IA_URI' ,  `data' will hold the
     accessLocation URI data.  Requesting this  `what' value leads to
     an error if the accessLocation is not of the
     "uniformResourceIdentifier" type.

     If  `what' is `GNUTLS_IA_OCSP_URI' ,  `data' will hold the OCSP
     URI.  Requesting this  `what' value leads to an error if the
     accessMethod is not 1.3.6.1.5.5.7.48.1 aka OSCP, or if
     accessLocation is not of the "uniformResourceIdentifier" type.

     If  `what' is `GNUTLS_IA_CAISSUERS_URI' ,  `data' will hold the
     caIssuers URI.  Requesting this  `what' value leads to an error if
     the accessMethod is not 1.3.6.1.5.5.7.48.2 aka caIssuers, or if
     accessLocation is not of the "uniformResourceIdentifier" type.

     More  `what' values may be allocated in the future as needed.

     If  `data' is NULL, the function does the same without storing the
     output data, that is, it will set  `critical' and do error checking
     as usual.

     The value of the critical flag is returned in * `critical' .
     Supply a NULL  `critical' if you want the function to make sure
     the extension is non-critical, as required by RFC 5280.

     *Returns:* `GNUTLS_E_SUCCESS'  on success,
     `GNUTLS_E_INVALID_REQUEST'  on invalid  `crt' ,
     `GNUTLS_E_CONSTRAINT_ERROR'  if the extension is incorrectly
     marked as critical (use a non-NULL  `critical' to override),
     `GNUTLS_E_UNKNOWN_ALGORITHM'  if the requested OID does not match
     (e.g., when using `GNUTLS_IA_OCSP_URI' ), otherwise a negative
     error code.

     *Since:* 3.0

gnutls_x509_crt_get_authority_key_gn_serial
-------------------------------------------

 -- Function: int gnutls_x509_crt_get_authority_key_gn_serial
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * ALT, size_t
          * ALT_SIZE, unsigned int * ALT_TYPE, void* SERIAL, size_t *
          SERIAL_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     ALT: is the place where the alternative name will be copied to

     ALT_SIZE: holds the size of alt.

     ALT_TYPE: holds the type of the alternative name (one of
     gnutls_x509_subject_alt_name_t).

     SERIAL: buffer to store the serial number (may be null)

     SERIAL_SIZE: Holds the size of the serial field (may be null)

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the X.509 authority key identifier when
     stored as a general name (authorityCertIssuer) and serial number.

     Because more than one general names might be stored  `seq' can be
     used as a counter to request them all until
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' if the extension is not
     present, otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_crt_get_authority_key_id
------------------------------------

 -- Function: int gnutls_x509_crt_get_authority_key_id
          (gnutls_x509_crt_t CERT, void * ID, size_t * ID_SIZE,
          unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     ID: The place where the identifier will be copied

     ID_SIZE: Holds the size of the id field.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the X.509v3 certificate authority's key
     identifier.  This is obtained by the X.509 Authority Key
     identifier extension field (2.5.29.35). Note that this function
     only returns the keyIdentifier field of the extension and
     `GNUTLS_E_X509_UNSUPPORTED_EXTENSION' , if the extension contains
     the name and serial number of the certificate. In that case
     `gnutls_x509_crt_get_authority_key_gn_serial()'  may be used.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' if the extension is not
     present, otherwise a negative error value.

gnutls_x509_crt_get_basic_constraints
-------------------------------------

 -- Function: int gnutls_x509_crt_get_basic_constraints
          (gnutls_x509_crt_t CERT, unsigned int * CRITICAL, unsigned
          int * CA, int * PATHLEN)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     CRITICAL: will be non (0) if the extension is marked as critical

     CA: pointer to output integer indicating CA status, may be NULL,
     value is 1 if the certificate CA flag is set, 0 otherwise.

     PATHLEN: pointer to output integer indicating path length (may be
     NULL), non-negative error codes indicate a present
     pathLenConstraint field and the actual value, -1 indicate that the
     field is absent.

     This function will read the certificate's basic constraints, and
     return the certificates CA status.  It reads the basicConstraints
     X.509 extension (2.5.29.19).

     *Returns:* If the certificate is a CA a positive value will be
     returned, or (0) if the certificate does not have CA flag set.  A
     negative error code may be returned in case of errors.  If the
     certificate does not contain the basicConstraints extension
     GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.

gnutls_x509_crt_get_ca_status
-----------------------------

 -- Function: int gnutls_x509_crt_get_ca_status (gnutls_x509_crt_t
          CERT, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     CRITICAL: will be non (0) if the extension is marked as critical

     This function will return certificates CA status, by reading the
     basicConstraints X.509 extension (2.5.29.19). If the certificate is
     a CA a positive value will be returned, or (0) if the certificate
     does not have CA flag set.

     Use `gnutls_x509_crt_get_basic_constraints()'  if you want to read
     the pathLenConstraint field too.

     *Returns:* A negative error code may be returned in case of
     parsing error.  If the certificate does not contain the
     basicConstraints extension `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'
     will be returned.

gnutls_x509_crt_get_crl_dist_points
-----------------------------------

 -- Function: int gnutls_x509_crt_get_crl_dist_points
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * RET, size_t
          * RET_SIZE, unsigned int * REASON_FLAGS, unsigned int *
          CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the distribution point (0
     for the first one, 1 for the second etc.)

     RET: is the place where the distribution point will be copied to

     RET_SIZE: holds the size of ret.

     REASON_FLAGS: Revocation reasons flags.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function retrieves the CRL distribution points (2.5.29.31),
     contained in the given certificate in the X509v3 Certificate
     Extensions.

     `reason_flags' should be an ORed sequence of
     `GNUTLS_CRL_REASON_UNUSED' , `GNUTLS_CRL_REASON_KEY_COMPROMISE' ,
     `GNUTLS_CRL_REASON_CA_COMPROMISE' ,
     `GNUTLS_CRL_REASON_AFFILIATION_CHANGED' ,
     `GNUTLS_CRL_REASON_SUPERSEEDED' ,
     `GNUTLS_CRL_REASON_CESSATION_OF_OPERATION' ,
     `GNUTLS_CRL_REASON_CERTIFICATE_HOLD' ,
     `GNUTLS_CRL_REASON_PRIVILEGE_WITHDRAWN' ,
     `GNUTLS_CRL_REASON_AA_COMPROMISE' , or (0) for all possible
     reasons.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  and updates  `ret_size'
     if  `ret_size' is not enough to hold the distribution point, or the
     type of the distribution point if everything was ok. The type is
     one of the enumerated `gnutls_x509_subject_alt_name_t' .  If the
     certificate does not have an Alternative name with the specified
     sequence number then `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is
     returned.

gnutls_x509_crt_get_dn
----------------------

 -- Function: int gnutls_x509_crt_get_dn (gnutls_x509_crt_t CERT, char
          * BUF, size_t * BUF_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     BUF: a pointer to a structure to hold the name (may be null)

     BUF_SIZE: initially holds the size of  `buf'

     This function will copy the name of the Certificate in the provided
     buffer. The name will be in the form "C=xxxx,O=yyyy,CN=zzzz" as
     described in RFC4514. The output string will be ASCII or UTF-8
     encoded, depending on the certificate data.

     If  `buf' is null then only the size will be filled.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the  `buf_size' will be
     updated with the required size.  On success 0 is returned.

gnutls_x509_crt_get_dn_by_oid
-----------------------------

 -- Function: int gnutls_x509_crt_get_dn_by_oid (gnutls_x509_crt_t
          CERT, const char * OID, int INDX, unsigned int RAW_FLAG, void
          * BUF, size_t * BUF_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the RDN, this specifies
     which to send. Use (0) to get the first one.

     RAW_FLAG: If non (0) returns the raw DER data of the DN part.

     BUF: a pointer where the DN part will be copied (may be null).

     BUF_SIZE: initially holds the size of  `buf'

     This function will extract the part of the name of the Certificate
     subject specified by the given OID. The output, if the raw flag is
     not used, will be encoded as described in RFC4514. Thus a string
     that is ASCII or UTF-8 encoded, depending on the certificate data.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     If raw flag is (0), this function will only return known OIDs as
     text. Other OIDs will be DER encoded, as described in RFC4514 - in
     hex format with a '#' prefix.  You can check about known OIDs
     using `gnutls_x509_dn_oid_known()' .

     If  `buf' is null then only the size will be filled. If the
     `raw_flag' is not specified the output is always null terminated,
     although the  `buf_size' will not include the null character.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the *buf_size will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_dn_oid
--------------------------

 -- Function: int gnutls_x509_crt_get_dn_oid (gnutls_x509_crt_t CERT,
          int INDX, void * OID, size_t * OID_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: This specifies which OID to return. Use (0) to get the first
     one.

     OID: a pointer to a buffer to hold the OID (may be null)

     OID_SIZE: initially holds the size of  `oid'

     This function will extract the OIDs of the name of the Certificate
     subject specified by the given index.

     If  `oid' is null then only the size will be filled. The  `oid'
     returned will be null terminated, although  `oid_size' will not
     account for the trailing null.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the  `oid_size' will be
     updated with the required size.  On success 0 is returned.

gnutls_x509_crt_get_expiration_time
-----------------------------------

 -- Function: time_t gnutls_x509_crt_get_expiration_time
          (gnutls_x509_crt_t CERT)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     This function will return the time this Certificate was or will be
     expired.

     *Returns:* expiration time, or (time_t)-1 on error.

gnutls_x509_crt_get_extension_by_oid
------------------------------------

 -- Function: int gnutls_x509_crt_get_extension_by_oid
          (gnutls_x509_crt_t CERT, const char * OID, int INDX, void *
          BUF, size_t * BUF_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the extensions, this
     specifies which to send. Use (0) to get the first one.

     BUF: a pointer to a structure to hold the name (may be null)

     BUF_SIZE: initially holds the size of  `buf'

     CRITICAL: will be non (0) if the extension is marked as critical

     This function will return the extension specified by the OID in the
     certificate.  The extensions will be returned as binary data DER
     encoded, in the provided buffer.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned. If the certificate
     does not contain the specified extension
     GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE will be returned.

gnutls_x509_crt_get_extension_data
----------------------------------

 -- Function: int gnutls_x509_crt_get_extension_data (gnutls_x509_crt_t
          CERT, int INDX, void * DATA, size_t * SIZEOF_DATA)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     DATA: a pointer to a structure to hold the data (may be null)

     SIZEOF_DATA: initially holds the size of  `oid'

     This function will return the requested extension data in the
     certificate.  The extension data will be stored as a string in the
     provided buffer.

     Use `gnutls_x509_crt_get_extension_info()'  to extract the OID and
     critical flag.  Use `gnutls_x509_crt_get_extension_by_oid()'
     instead, if you want to get data indexed by the extension OID
     rather than sequence.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

gnutls_x509_crt_get_extension_info
----------------------------------

 -- Function: int gnutls_x509_crt_get_extension_info (gnutls_x509_crt_t
          CERT, int INDX, void * OID, size_t * OID_SIZE, unsigned int *
          CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID

     OID_SIZE: initially holds the maximum size of  `oid' , on return
     holds actual size of  `oid' .

     CRITICAL: output variable with critical flag, may be NULL.

     This function will return the requested extension OID in the
     certificate, and the critical flag for it.  The extension OID will
     be stored as a string in the provided buffer.  Use
     `gnutls_x509_crt_get_extension_data()'  to extract the data.

     If the buffer provided is not long enough to hold the output, then
     `oid_size' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'  will be
     returned. The  `oid' returned will be null terminated, although
     `oid_size' will not account for the trailing null.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

gnutls_x509_crt_get_extension_oid
---------------------------------

 -- Function: int gnutls_x509_crt_get_extension_oid (gnutls_x509_crt_t
          CERT, int INDX, void * OID, size_t * OID_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: Specifies which extension OID to send. Use (0) to get the
     first one.

     OID: a pointer to a structure to hold the OID (may be null)

     OID_SIZE: initially holds the size of  `oid'

     This function will return the requested extension OID in the
     certificate.  The extension OID will be stored as a string in the
     provided buffer.

     The  `oid' returned will be null terminated, although  `oid_size'
     will not account for the trailing null.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' will be returned.

gnutls_x509_crt_get_fingerprint
-------------------------------

 -- Function: int gnutls_x509_crt_get_fingerprint (gnutls_x509_crt_t
          CERT, gnutls_digest_algorithm_t ALGO, void * BUF, size_t *
          BUF_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     ALGO: is a digest algorithm

     BUF: a pointer to a structure to hold the fingerprint (may be null)

     BUF_SIZE: initially holds the size of  `buf'

     This function will calculate and copy the certificate's fingerprint
     in the provided buffer.

     If the buffer is null then only the size will be filled.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the *buf_size will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_issuer
--------------------------

 -- Function: int gnutls_x509_crt_get_issuer (gnutls_x509_crt_t CERT,
          gnutls_x509_dn_t * DN)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     DN: output variable with pointer to uint8_t DN

     Return the Certificate's Issuer DN as an uint8_t data type.  You
     may use `gnutls_x509_dn_get_rdn_ava()'  to decode the DN.

     Note that  `dn' should be treated as constant. Because points into
     the  `cert' object, you may not deallocate  `cert' and continue to
     access  `dn' .

     *Returns:* Returns 0 on success, or an error code.

gnutls_x509_crt_get_issuer_alt_name
-----------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_alt_name
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * IAN, size_t
          * IAN_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     IAN: is the place where the alternative name will be copied to

     IAN_SIZE: holds the size of ian.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function retrieves the Issuer Alternative Name (2.5.29.18),
     contained in the given certificate in the X509v3 Certificate
     Extensions.

     When the SAN type is otherName, it will extract the data in the
     otherName's value field, and `GNUTLS_SAN_OTHERNAME'  is returned.
     You may use `gnutls_x509_crt_get_subject_alt_othername_oid()'  to
     get the corresponding OID and the "virtual" SAN types (e.g.,
     `GNUTLS_SAN_OTHERNAME_XMPP' ).

     If an otherName OID is known, the data will be decoded.  Otherwise
     the returned data will be DER encoded, and you will have to decode
     it yourself.  Currently, only the RFC 3920 id-on-xmppAddr Issuer
     AltName is recognized.

     *Returns:* the alternative issuer name type on success, one of the
     enumerated `gnutls_x509_subject_alt_name_t' .  It will return
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  if  `ian_size' is not large enough
     to hold the value.  In that case  `ian_size' will be updated with
     the required size.  If the certificate does not have an
     Alternative name with the specified sequence number then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Since:* 2.10.0

gnutls_x509_crt_get_issuer_alt_name2
------------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_alt_name2
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * IAN, size_t
          * IAN_SIZE, unsigned int * IAN_TYPE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     IAN: is the place where the alternative name will be copied to

     IAN_SIZE: holds the size of ret.

     IAN_TYPE: holds the type of the alternative name (one of
     gnutls_x509_subject_alt_name_t).

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the alternative names, contained in the
     given certificate. It is the same as
     `gnutls_x509_crt_get_issuer_alt_name()'  except for the fact that
     it will return the type of the alternative name in  `ian_type'
     even if the function fails for some reason (i.e.  the buffer
     provided is not enough).

     *Returns:* the alternative issuer name type on success, one of the
     enumerated `gnutls_x509_subject_alt_name_t' .  It will return
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  if  `ian_size' is not large enough
     to hold the value.  In that case  `ian_size' will be updated with
     the required size.  If the certificate does not have an
     Alternative name with the specified sequence number then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Since:* 2.10.0

gnutls_x509_crt_get_issuer_alt_othername_oid
--------------------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_alt_othername_oid
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * RET, size_t
          * RET_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     RET: is the place where the otherName OID will be copied to

     RET_SIZE: holds the size of ret.

     This function will extract the type OID of an otherName Subject
     Alternative Name, contained in the given certificate, and return
     the type as an enumerated element.

     If  `oid' is null then only the size will be filled. The  `oid'
     returned will be null terminated, although  `oid_size' will not
     account for the trailing null.

     This function is only useful if
     `gnutls_x509_crt_get_issuer_alt_name()'  returned
     `GNUTLS_SAN_OTHERNAME' .

     *Returns:* the alternative issuer name type on success, one of the
     enumerated gnutls_x509_subject_alt_name_t.  For supported OIDs, it
     will return one of the virtual (GNUTLS_SAN_OTHERNAME_*) types,
     e.g. `GNUTLS_SAN_OTHERNAME_XMPP' , and `GNUTLS_SAN_OTHERNAME'  for
     unknown OIDs.  It will return `GNUTLS_E_SHORT_MEMORY_BUFFER'  if
     `ret_size' is not large enough to hold the value.  In that case
     `ret_size' will be updated with the required size.  If the
     certificate does not have an Alternative name with the specified
     sequence number and with the otherName type then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

     *Since:* 2.10.0

gnutls_x509_crt_get_issuer_dn
-----------------------------

 -- Function: int gnutls_x509_crt_get_issuer_dn (gnutls_x509_crt_t
          CERT, char * BUF, size_t * BUF_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     BUF: a pointer to a structure to hold the name (may be null)

     BUF_SIZE: initially holds the size of  `buf'

     This function will copy the name of the Certificate issuer in the
     provided buffer. The name will be in the form
     "C=xxxx,O=yyyy,CN=zzzz" as described in RFC4514. The output string
     will be ASCII or UTF-8 encoded, depending on the certificate data.

     If  `buf' is null then only the size will be filled.

     *Returns:* GNUTLS_E_SHORT_MEMORY_BUFFER if the provided buffer is
     not long enough, and in that case the  `buf_size' will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_issuer_dn_by_oid
------------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_dn_by_oid
          (gnutls_x509_crt_t CERT, const char * OID, int INDX, unsigned
          int RAW_FLAG, void * BUF, size_t * BUF_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     OID: holds an Object Identified in null terminated string

     INDX: In case multiple same OIDs exist in the RDN, this specifies
     which to send. Use (0) to get the first one.

     RAW_FLAG: If non (0) returns the raw DER data of the DN part.

     BUF: a pointer to a structure to hold the name (may be null)

     BUF_SIZE: initially holds the size of  `buf'

     This function will extract the part of the name of the Certificate
     issuer specified by the given OID. The output, if the raw flag is
     not used, will be encoded as described in RFC4514. Thus a string
     that is ASCII or UTF-8 encoded, depending on the certificate data.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     If raw flag is (0), this function will only return known OIDs as
     text. Other OIDs will be DER encoded, as described in RFC4514 - in
     hex format with a '#' prefix.  You can check about known OIDs
     using `gnutls_x509_dn_oid_known()' .

     If  `buf' is null then only the size will be filled. If the
     `raw_flag' is not specified the output is always null terminated,
     although the  `buf_size' will not include the null character.

     *Returns:* GNUTLS_E_SHORT_MEMORY_BUFFER if the provided buffer is
     not long enough, and in that case the  `buf_size' will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_issuer_dn_oid
---------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_dn_oid (gnutls_x509_crt_t
          CERT, int INDX, void * OID, size_t * OID_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: This specifies which OID to return. Use (0) to get the first
     one.

     OID: a pointer to a buffer to hold the OID (may be null)

     OID_SIZE: initially holds the size of  `oid'

     This function will extract the OIDs of the name of the Certificate
     issuer specified by the given index.

     If  `oid' is null then only the size will be filled. The  `oid'
     returned will be null terminated, although  `oid_size' will not
     account for the trailing null.

     *Returns:* GNUTLS_E_SHORT_MEMORY_BUFFER if the provided buffer is
     not long enough, and in that case the  `oid_size' will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_issuer_unique_id
------------------------------------

 -- Function: int gnutls_x509_crt_get_issuer_unique_id
          (gnutls_x509_crt_t CRT, char * BUF, size_t * BUF_SIZE)
     CRT: Holds the certificate

     BUF: user allocated memory buffer, will hold the unique id

     BUF_SIZE: size of user allocated memory buffer (on input), will
     hold actual size of the unique ID on return.

     This function will extract the issuerUniqueID value (if present)
     for the given certificate.

     If the user allocated memory buffer is not large enough to hold the
     full subjectUniqueID, then a GNUTLS_E_SHORT_MEMORY_BUFFER error
     will be returned, and buf_size will be set to the actual length.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.12.0

gnutls_x509_crt_get_key_id
--------------------------

 -- Function: int gnutls_x509_crt_get_key_id (gnutls_x509_crt_t CRT,
          unsigned int FLAGS, unsigned char * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     CRT: Holds the certificate

     FLAGS: should be 0 for now

     OUTPUT_DATA: will contain the key ID

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will return a unique ID the depends on the public
     key parameters. This ID can be used in checking whether a
     certificate corresponds to the given private key.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
     be returned.  The output will normally be a SHA-1 hash output,
     which is 20 bytes.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_x509_crt_get_key_purpose_oid
-----------------------------------

 -- Function: int gnutls_x509_crt_get_key_purpose_oid
          (gnutls_x509_crt_t CERT, int INDX, void * OID, size_t *
          OID_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     INDX: This specifies which OID to return. Use (0) to get the first
     one.

     OID: a pointer to a buffer to hold the OID (may be null)

     OID_SIZE: initially holds the size of  `oid'

     CRITICAL: output flag to indicate criticality of extension

     This function will extract the key purpose OIDs of the Certificate
     specified by the given index.  These are stored in the Extended Key
     Usage extension (2.5.29.37) See the GNUTLS_KP_* definitions for
     human readable names.

     If  `oid' is null then only the size will be filled. The  `oid'
     returned will be null terminated, although  `oid_size' will not
     account for the trailing null.

     *Returns:* `GNUTLS_E_SHORT_MEMORY_BUFFER'  if the provided buffer
     is not long enough, and in that case the *oid_size will be updated
     with the required size.  On success 0 is returned.

gnutls_x509_crt_get_key_usage
-----------------------------

 -- Function: int gnutls_x509_crt_get_key_usage (gnutls_x509_crt_t
          CERT, unsigned int * KEY_USAGE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     KEY_USAGE: where the key usage bits will be stored

     CRITICAL: will be non (0) if the extension is marked as critical

     This function will return certificate's key usage, by reading the
     keyUsage X.509 extension (2.5.29.15). The key usage value will ORed
     values of the: `GNUTLS_KEY_DIGITAL_SIGNATURE' ,
     `GNUTLS_KEY_NON_REPUDIATION' , `GNUTLS_KEY_KEY_ENCIPHERMENT' ,
     `GNUTLS_KEY_DATA_ENCIPHERMENT' , `GNUTLS_KEY_KEY_AGREEMENT' ,
     `GNUTLS_KEY_KEY_CERT_SIGN' , `GNUTLS_KEY_CRL_SIGN' ,
     `GNUTLS_KEY_ENCIPHER_ONLY' , `GNUTLS_KEY_DECIPHER_ONLY' .

     *Returns:* the certificate key usage, or a negative error code in
     case of parsing error.  If the certificate does not contain the
     keyUsage extension `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be
     returned.

gnutls_x509_crt_get_pk_algorithm
--------------------------------

 -- Function: int gnutls_x509_crt_get_pk_algorithm (gnutls_x509_crt_t
          CERT, unsigned int * BITS)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of an X.509
     certificate.

     If bits is non null, it should have enough size to hold the
     parameters size in bits. For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

gnutls_x509_crt_get_pk_dsa_raw
------------------------------

 -- Function: int gnutls_x509_crt_get_pk_dsa_raw (gnutls_x509_crt_t
          CRT, gnutls_datum_t * P, gnutls_datum_t * Q, gnutls_datum_t *
          G, gnutls_datum_t * Y)
     CRT: Holds the certificate

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     This function will export the DSA public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

gnutls_x509_crt_get_pk_rsa_raw
------------------------------

 -- Function: int gnutls_x509_crt_get_pk_rsa_raw (gnutls_x509_crt_t
          CRT, gnutls_datum_t * M, gnutls_datum_t * E)
     CRT: Holds the certificate

     M: will hold the modulus

     E: will hold the public exponent

     This function will export the RSA public key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

gnutls_x509_crt_get_private_key_usage_period
--------------------------------------------

 -- Function: int gnutls_x509_crt_get_private_key_usage_period
          (gnutls_x509_crt_t CERT, time_t* ACTIVATION, time_t*
          EXPIRATION, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     ACTIVATION: The activation time

     EXPIRATION: The expiration time

     CRITICAL: the extension status

     This function will return the expiration and activation times of
     the private key of the certificate. It relies on the PKIX
     extension 2.5.29.16 being present.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' if the extension is not
     present, otherwise a negative error value.

gnutls_x509_crt_get_proxy
-------------------------

 -- Function: int gnutls_x509_crt_get_proxy (gnutls_x509_crt_t CERT,
          unsigned int * CRITICAL, int * PATHLEN, char **
          POLICYLANGUAGE, char ** POLICY, size_t * SIZEOF_POLICY)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     CRITICAL: will be non (0) if the extension is marked as critical

     PATHLEN: pointer to output integer indicating path length (may be
     NULL), non-negative error codes indicate a present
     pCPathLenConstraint field and the actual value, -1 indicate that
     the field is absent.

     POLICYLANGUAGE: output variable with OID of policy language

     POLICY: output variable with policy data

     SIZEOF_POLICY: output variable size of policy data

     This function will get information from a proxy certificate.  It
     reads the ProxyCertInfo X.509 extension (1.3.6.1.5.5.7.1.14).

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_x509_crt_get_raw_dn
--------------------------

 -- Function: int gnutls_x509_crt_get_raw_dn (gnutls_x509_crt_t CERT,
          gnutls_datum_t * START)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     START: will hold the starting point of the DN

     This function will return a pointer to the DER encoded DN
     structure and the length.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. or a negative error code on
     error.

gnutls_x509_crt_get_raw_issuer_dn
---------------------------------

 -- Function: int gnutls_x509_crt_get_raw_issuer_dn (gnutls_x509_crt_t
          CERT, gnutls_datum_t * START)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     START: will hold the starting point of the DN

     This function will return a pointer to the DER encoded DN structure
     and the length.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.or a negative error code on error.

gnutls_x509_crt_get_serial
--------------------------

 -- Function: int gnutls_x509_crt_get_serial (gnutls_x509_crt_t CERT,
          void * RESULT, size_t * RESULT_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     RESULT: The place where the serial number will be copied

     RESULT_SIZE: Holds the size of the result field.

     This function will return the X.509 certificate's serial number.
     This is obtained by the X509 Certificate serialNumber field. Serial
     is not always a 32 or 64bit number. Some CAs use large serial
     numbers, thus it may be wise to handle it as something uint8_t.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_get_signature
-----------------------------

 -- Function: int gnutls_x509_crt_get_signature (gnutls_x509_crt_t
          CERT, char * SIG, size_t * SIZEOF_SIG)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SIG: a pointer where the signature part will be copied (may be
     null).

     SIZEOF_SIG: initially holds the size of  `sig'

     This function will extract the signature field of a certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. and a negative error code on
     error.

gnutls_x509_crt_get_signature_algorithm
---------------------------------------

 -- Function: int gnutls_x509_crt_get_signature_algorithm
          (gnutls_x509_crt_t CERT)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     This function will return a value of the `gnutls_sign_algorithm_t'
     enumeration that is the signature algorithm that has been used to
     sign this certificate.

     *Returns:* a `gnutls_sign_algorithm_t'  value, or a negative error
     code on error.

gnutls_x509_crt_get_subject
---------------------------

 -- Function: int gnutls_x509_crt_get_subject (gnutls_x509_crt_t CERT,
          gnutls_x509_dn_t * DN)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     DN: output variable with pointer to uint8_t DN.

     Return the Certificate's Subject DN as an uint8_t data type.  You
     may use `gnutls_x509_dn_get_rdn_ava()'  to decode the DN.

     Note that  `dn' should be treated as constant. Because points into
     the  `cert' object, you may not deallocate  `cert' and continue to
     access  `dn' .

     *Returns:* Returns 0 on success, or an error code.

gnutls_x509_crt_get_subject_alt_name
------------------------------------

 -- Function: int gnutls_x509_crt_get_subject_alt_name
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * SAN, size_t
          * SAN_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     SAN: is the place where the alternative name will be copied to

     SAN_SIZE: holds the size of san.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function retrieves the Alternative Name (2.5.29.17), contained
     in the given certificate in the X509v3 Certificate Extensions.

     When the SAN type is otherName, it will extract the data in the
     otherName's value field, and `GNUTLS_SAN_OTHERNAME'  is returned.
     You may use `gnutls_x509_crt_get_subject_alt_othername_oid()'  to
     get the corresponding OID and the "virtual" SAN types (e.g.,
     `GNUTLS_SAN_OTHERNAME_XMPP' ).

     If an otherName OID is known, the data will be decoded.  Otherwise
     the returned data will be DER encoded, and you will have to decode
     it yourself.  Currently, only the RFC 3920 id-on-xmppAddr SAN is
     recognized.

     *Returns:* the alternative subject name type on success, one of the
     enumerated `gnutls_x509_subject_alt_name_t' .  It will return
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  if  `san_size' is not large enough
     to hold the value.  In that case  `san_size' will be updated with
     the required size.  If the certificate does not have an Alternative
     name with the specified sequence number then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

gnutls_x509_crt_get_subject_alt_name2
-------------------------------------

 -- Function: int gnutls_x509_crt_get_subject_alt_name2
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * SAN, size_t
          * SAN_SIZE, unsigned int * SAN_TYPE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     SAN: is the place where the alternative name will be copied to

     SAN_SIZE: holds the size of ret.

     SAN_TYPE: holds the type of the alternative name (one of
     gnutls_x509_subject_alt_name_t).

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the alternative names, contained in the
     given certificate. It is the same as
     `gnutls_x509_crt_get_subject_alt_name()'  except for the fact that
     it will return the type of the alternative name in  `san_type'
     even if the function fails for some reason (i.e.  the buffer
     provided is not enough).

     *Returns:* the alternative subject name type on success, one of the
     enumerated `gnutls_x509_subject_alt_name_t' .  It will return
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  if  `san_size' is not large enough
     to hold the value.  In that case  `san_size' will be updated with
     the required size.  If the certificate does not have an
     Alternative name with the specified sequence number then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

gnutls_x509_crt_get_subject_alt_othername_oid
---------------------------------------------

 -- Function: int gnutls_x509_crt_get_subject_alt_othername_oid
          (gnutls_x509_crt_t CERT, unsigned int SEQ, void * OID, size_t
          * OID_SIZE)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     SEQ: specifies the sequence number of the alt name (0 for the
     first one, 1 for the second etc.)

     OID: is the place where the otherName OID will be copied to

     OID_SIZE: holds the size of ret.

     This function will extract the type OID of an otherName Subject
     Alternative Name, contained in the given certificate, and return
     the type as an enumerated element.

     This function is only useful if
     `gnutls_x509_crt_get_subject_alt_name()'  returned
     `GNUTLS_SAN_OTHERNAME' .

     If  `oid' is null then only the size will be filled. The  `oid'
     returned will be null terminated, although  `oid_size' will not
     account for the trailing null.

     *Returns:* the alternative subject name type on success, one of the
     enumerated gnutls_x509_subject_alt_name_t.  For supported OIDs, it
     will return one of the virtual (GNUTLS_SAN_OTHERNAME_*) types,
     e.g. `GNUTLS_SAN_OTHERNAME_XMPP' , and `GNUTLS_SAN_OTHERNAME'  for
     unknown OIDs.  It will return `GNUTLS_E_SHORT_MEMORY_BUFFER'  if
     `ian_size' is not large enough to hold the value.  In that case
     `ian_size' will be updated with the required size.  If the
     certificate does not have an Alternative name with the specified
     sequence number and with the otherName type then
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  is returned.

gnutls_x509_crt_get_subject_key_id
----------------------------------

 -- Function: int gnutls_x509_crt_get_subject_key_id (gnutls_x509_crt_t
          CERT, void * RET, size_t * RET_SIZE, unsigned int * CRITICAL)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     RET: The place where the identifier will be copied

     RET_SIZE: Holds the size of the result field.

     CRITICAL: will be non (0) if the extension is marked as critical
     (may be null)

     This function will return the X.509v3 certificate's subject key
     identifier.  This is obtained by the X.509 Subject Key identifier
     extension field (2.5.29.14).

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' if the extension is not
     present, otherwise a negative error value.

gnutls_x509_crt_get_subject_unique_id
-------------------------------------

 -- Function: int gnutls_x509_crt_get_subject_unique_id
          (gnutls_x509_crt_t CRT, char * BUF, size_t * BUF_SIZE)
     CRT: Holds the certificate

     BUF: user allocated memory buffer, will hold the unique id

     BUF_SIZE: size of user allocated memory buffer (on input), will
     hold actual size of the unique ID on return.

     This function will extract the subjectUniqueID value (if present)
     for the given certificate.

     If the user allocated memory buffer is not large enough to hold the
     full subjectUniqueID, then a GNUTLS_E_SHORT_MEMORY_BUFFER error
     will be returned, and buf_size will be set to the actual length.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

gnutls_x509_crt_get_version
---------------------------

 -- Function: int gnutls_x509_crt_get_version (gnutls_x509_crt_t CERT)
     CERT: should contain a `gnutls_x509_crt_t'  structure

     This function will return the version of the specified Certificate.

     *Returns:* version of certificate, or a negative error code on
     error.

gnutls_x509_crt_import
----------------------

 -- Function: int gnutls_x509_crt_import (gnutls_x509_crt_t CERT, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT)
     CERT: The structure to store the parsed certificate.

     DATA: The DER or PEM encoded certificate.

     FORMAT: One of DER or PEM

     This function will convert the given DER or PEM encoded Certificate
     to the native gnutls_x509_crt_t format. The output will be stored
     in  `cert' .

     If the Certificate is PEM encoded it should have a header of "X509
     CERTIFICATE", or "CERTIFICATE".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_init
--------------------

 -- Function: int gnutls_x509_crt_init (gnutls_x509_crt_t * CERT)
     CERT: The structure to be initialized

     This function will initialize an X.509 certificate structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_list_import
---------------------------

 -- Function: int gnutls_x509_crt_list_import (gnutls_x509_crt_t *
          CERTS, unsigned int * CERT_MAX, const gnutls_datum_t * DATA,
          gnutls_x509_crt_fmt_t FORMAT, unsigned int FLAGS)
     CERTS: The structures to store the parsed certificate. Must not be
     initialized.

     CERT_MAX: Initially must hold the maximum number of certs. It will
     be updated with the number of certs available.

     DATA: The PEM encoded certificate.

     FORMAT: One of DER or PEM.

     FLAGS: must be (0) or an OR'd sequence of
     gnutls_certificate_import_flags.

     This function will convert the given PEM encoded certificate list
     to the native gnutls_x509_crt_t format. The output will be stored
     in  `certs' .  They will be automatically initialized.

     The flag `GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED'  will cause
     import to fail if the certificates in the provided buffer are more
     than the available structures. The
     `GNUTLS_X509_CRT_LIST_FAIL_IF_UNSORTED' flag will cause the
     function to fail if the provided list is not sorted from subject
     to issuer.

     If the Certificate is PEM encoded it should have a header of "X509
     CERTIFICATE", or "CERTIFICATE".

     *Returns:* the number of certificates read or a negative error
     value.

gnutls_x509_crt_list_import2
----------------------------

 -- Function: int gnutls_x509_crt_list_import2 (gnutls_x509_crt_t **
          CERTS, unsigned int * SIZE, const gnutls_datum_t * DATA,
          gnutls_x509_crt_fmt_t FORMAT, unsigned int FLAGS)
     CERTS: The structures to store the parsed certificate. Must not be
     initialized.

     SIZE: It will contain the size of the list.

     DATA: The PEM encoded certificate.

     FORMAT: One of DER or PEM.

     FLAGS: must be (0) or an OR'd sequence of
     gnutls_certificate_import_flags.

     This function will convert the given PEM encoded certificate list
     to the native gnutls_x509_crt_t format. The output will be stored
     in  `certs' which will be initialized.

     If the Certificate is PEM encoded it should have a header of "X509
     CERTIFICATE", or "CERTIFICATE".

     *Returns:* the number of certificates read or a negative error
     value.

     *Since:* 3.0

gnutls_x509_crt_list_verify
---------------------------

 -- Function: int gnutls_x509_crt_list_verify (const gnutls_x509_crt_t
          * CERT_LIST, int CERT_LIST_LENGTH, const gnutls_x509_crt_t *
          CA_LIST, int CA_LIST_LENGTH, const gnutls_x509_crl_t *
          CRL_LIST, int CRL_LIST_LENGTH, unsigned int FLAGS, unsigned
          int * VERIFY)
     CERT_LIST: is the certificate list to be verified

     CERT_LIST_LENGTH: holds the number of certificate in cert_list

     CA_LIST: is the CA list which will be used in verification

     CA_LIST_LENGTH: holds the number of CA certificate in CA_list

     CRL_LIST: holds a list of CRLs.

     CRL_LIST_LENGTH: the length of CRL list.

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     VERIFY: will hold the certificate verification output.

     This function will try to verify the given certificate list and
     return its status.  If no flags are specified (0), this function
     will use the basicConstraints (2.5.29.19) PKIX extension. This
     means that only a certificate authority is allowed to sign a
     certificate.

     You must also check the peer's name in order to check if the
     verified certificate belongs to the actual peer.

     The certificate verification output will be put in  `verify' and
     will be one or more of the gnutls_certificate_status_t enumerated
     elements bitwise or'd.  For a more detailed verification status use
     `gnutls_x509_crt_verify()'  per list element.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_print
---------------------

 -- Function: int gnutls_x509_crt_print (gnutls_x509_crt_t CERT,
          gnutls_certificate_print_formats_t FORMAT, gnutls_datum_t *
          OUT)
     CERT: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print a X.509 certificate, suitable for
     display to a human.

     If the format is `GNUTLS_CRT_PRINT_FULL'  then all fields of the
     certificate will be output, on multiple lines.  The
     `GNUTLS_CRT_PRINT_ONELINE'  format will generate one line with some
     selected fields, which is useful for logging purposes.

     The output  `out' needs to be deallocate using `gnutls_free()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_activation_time
-----------------------------------

 -- Function: int gnutls_x509_crt_set_activation_time
          (gnutls_x509_crt_t CERT, time_t ACT_TIME)
     CERT: a certificate of type `gnutls_x509_crt_t'

     ACT_TIME: The actual time

     This function will set the time this Certificate was or will be
     activated.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_authority_info_access
-----------------------------------------

 -- Function: int gnutls_x509_crt_set_authority_info_access
          (gnutls_x509_crt_t CRT, int WHAT, gnutls_datum_t * DATA)
     CRT: Holds the certificate

     WHAT: what data to get, a `gnutls_info_access_what_t'  type.

     DATA: output data to be freed with `gnutls_free()' .

     This function sets the Authority Information Access (AIA)
     extension, see RFC 5280 section 4.2.2.1 for more information.

     The type of data stored in  `data' is specified via  `what' which
     should be `gnutls_info_access_what_t'  values.

     If  `what' is `GNUTLS_IA_OCSP_URI' ,  `data' will hold the OCSP
     URI.  If  `what' is `GNUTLS_IA_CAISSUERS_URI' ,  `data' will hold
     the caIssuers URI.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_crt_set_authority_key_id
------------------------------------

 -- Function: int gnutls_x509_crt_set_authority_key_id
          (gnutls_x509_crt_t CERT, const void * ID, size_t ID_SIZE)
     CERT: a certificate of type `gnutls_x509_crt_t'

     ID: The key ID

     ID_SIZE: Holds the size of the serial field.

     This function will set the X.509 certificate's authority key ID
     extension.  Only the keyIdentifier field can be set with this
     function.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_basic_constraints
-------------------------------------

 -- Function: int gnutls_x509_crt_set_basic_constraints
          (gnutls_x509_crt_t CRT, unsigned int CA, int
          PATHLENCONSTRAINT)
     CRT: a certificate of type `gnutls_x509_crt_t'

     CA: true(1) or false(0). Depending on the Certificate authority
     status.

     PATHLENCONSTRAINT: non-negative error codes indicate maximum
     length of path, and negative error codes indicate that the
     pathLenConstraints field should not be present.

     This function will set the basicConstraints certificate extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_ca_status
-----------------------------

 -- Function: int gnutls_x509_crt_set_ca_status (gnutls_x509_crt_t CRT,
          unsigned int CA)
     CRT: a certificate of type `gnutls_x509_crt_t'

     CA: true(1) or false(0). Depending on the Certificate authority
     status.

     This function will set the basicConstraints certificate extension.
     Use `gnutls_x509_crt_set_basic_constraints()'  if you want to
     control the pathLenConstraint field too.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_crl_dist_points
-----------------------------------

 -- Function: int gnutls_x509_crt_set_crl_dist_points
          (gnutls_x509_crt_t CRT, gnutls_x509_subject_alt_name_t TYPE,
          const void * DATA_STRING, unsigned int REASON_FLAGS)
     CRT: a certificate of type `gnutls_x509_crt_t'

     TYPE: is one of the gnutls_x509_subject_alt_name_t enumerations

     DATA_STRING: The data to be set

     REASON_FLAGS: revocation reasons

     This function will set the CRL distribution points certificate
     extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_crl_dist_points2
------------------------------------

 -- Function: int gnutls_x509_crt_set_crl_dist_points2
          (gnutls_x509_crt_t CRT, gnutls_x509_subject_alt_name_t TYPE,
          const void * DATA, unsigned int DATA_SIZE, unsigned int
          REASON_FLAGS)
     CRT: a certificate of type `gnutls_x509_crt_t'

     TYPE: is one of the gnutls_x509_subject_alt_name_t enumerations

     DATA: The data to be set

     DATA_SIZE: The data size

     REASON_FLAGS: revocation reasons

     This function will set the CRL distribution points certificate
     extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.6.0

gnutls_x509_crt_set_crq
-----------------------

 -- Function: int gnutls_x509_crt_set_crq (gnutls_x509_crt_t CRT,
          gnutls_x509_crq_t CRQ)
     CRT: a certificate of type `gnutls_x509_crt_t'

     CRQ: holds a certificate request

     This function will set the name and public parameters as well as
     the extensions from the given certificate request to the
     certificate.  Only RSA keys are currently supported.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_crq_extensions
----------------------------------

 -- Function: int gnutls_x509_crt_set_crq_extensions (gnutls_x509_crt_t
          CRT, gnutls_x509_crq_t CRQ)
     CRT: a certificate of type `gnutls_x509_crt_t'

     CRQ: holds a certificate request

     This function will set extensions from the given request to the
     certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.8.0

gnutls_x509_crt_set_dn_by_oid
-----------------------------

 -- Function: int gnutls_x509_crt_set_dn_by_oid (gnutls_x509_crt_t CRT,
          const char * OID, unsigned int RAW_FLAG, const void * NAME,
          unsigned int SIZEOF_NAME)
     CRT: a certificate of type `gnutls_x509_crt_t'

     OID: holds an Object Identifier in a null terminated string

     RAW_FLAG: must be 0, or 1 if the data are DER encoded

     NAME: a pointer to the name

     SIZEOF_NAME: holds the size of  `name'

     This function will set the part of the name of the Certificate
     subject, specified by the given OID. The input string should be
     ASCII or UTF-8 encoded.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     With this function you can only set the known OIDs. You can test
     for known OIDs using `gnutls_x509_dn_oid_known()' . For OIDs that
     are not known (by gnutls) you should properly DER encode your data,
     and call this function with  `raw_flag' set.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_expiration_time
-----------------------------------

 -- Function: int gnutls_x509_crt_set_expiration_time
          (gnutls_x509_crt_t CERT, time_t EXP_TIME)
     CERT: a certificate of type `gnutls_x509_crt_t'

     EXP_TIME: The actual time

     This function will set the time this Certificate will expire.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_extension_by_oid
------------------------------------

 -- Function: int gnutls_x509_crt_set_extension_by_oid
          (gnutls_x509_crt_t CRT, const char * OID, const void * BUF,
          size_t SIZEOF_BUF, unsigned int CRITICAL)
     CRT: a certificate of type `gnutls_x509_crt_t'

     OID: holds an Object Identified in null terminated string

     BUF: a pointer to a DER encoded data

     SIZEOF_BUF: holds the size of  `buf'

     CRITICAL: should be non (0) if the extension is to be marked as
     critical

     This function will set an the extension, by the specified OID, in
     the certificate.  The extension data should be binary data DER
     encoded.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_issuer_dn_by_oid
------------------------------------

 -- Function: int gnutls_x509_crt_set_issuer_dn_by_oid
          (gnutls_x509_crt_t CRT, const char * OID, unsigned int
          RAW_FLAG, const void * NAME, unsigned int SIZEOF_NAME)
     CRT: a certificate of type `gnutls_x509_crt_t'

     OID: holds an Object Identifier in a null terminated string

     RAW_FLAG: must be 0, or 1 if the data are DER encoded

     NAME: a pointer to the name

     SIZEOF_NAME: holds the size of  `name'

     This function will set the part of the name of the Certificate
     issuer, specified by the given OID.  The input string should be
     ASCII or UTF-8 encoded.

     Some helper macros with popular OIDs can be found in gnutls/x509.h
     With this function you can only set the known OIDs. You can test
     for known OIDs using `gnutls_x509_dn_oid_known()' . For OIDs that
     are not known (by gnutls) you should properly DER encode your data,
     and call this function with  `raw_flag' set.

     Normally you do not need to call this function, since the signing
     operation will copy the signer's name as the issuer of the
     certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_key
-----------------------

 -- Function: int gnutls_x509_crt_set_key (gnutls_x509_crt_t CRT,
          gnutls_x509_privkey_t KEY)
     CRT: a certificate of type `gnutls_x509_crt_t'

     KEY: holds a private key

     This function will set the public parameters from the given
     private key to the certificate. Only RSA keys are currently
     supported.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_key_purpose_oid
-----------------------------------

 -- Function: int gnutls_x509_crt_set_key_purpose_oid
          (gnutls_x509_crt_t CERT, const void * OID, unsigned int
          CRITICAL)
     CERT: a certificate of type `gnutls_x509_crt_t'

     OID: a pointer to a null terminated string that holds the OID

     CRITICAL: Whether this extension will be critical or not

     This function will set the key purpose OIDs of the Certificate.
     These are stored in the Extended Key Usage extension (2.5.29.37)
     See the GNUTLS_KP_* definitions for human readable names.

     Subsequent calls to this function will append OIDs to the OID list.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_x509_crt_set_key_usage
-----------------------------

 -- Function: int gnutls_x509_crt_set_key_usage (gnutls_x509_crt_t CRT,
          unsigned int USAGE)
     CRT: a certificate of type `gnutls_x509_crt_t'

     USAGE: an ORed sequence of the GNUTLS_KEY_* elements.

     This function will set the keyUsage certificate extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_private_key_usage_period
--------------------------------------------

 -- Function: int gnutls_x509_crt_set_private_key_usage_period
          (gnutls_x509_crt_t CRT, time_t ACTIVATION, time_t EXPIRATION)
     CRT: a certificate of type `gnutls_x509_crt_t'

     ACTIVATION: The activation time

     EXPIRATION: The expiration time

     This function will set the private key usage period extension
     (2.5.29.16).

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_proxy
-------------------------

 -- Function: int gnutls_x509_crt_set_proxy (gnutls_x509_crt_t CRT, int
          PATHLENCONSTRAINT, const char * POLICYLANGUAGE, const char *
          POLICY, size_t SIZEOF_POLICY)
     CRT: a certificate of type `gnutls_x509_crt_t'

     PATHLENCONSTRAINT: non-negative error codes indicate maximum
     length of path, and negative error codes indicate that the
     pathLenConstraints field should not be present.

     POLICYLANGUAGE: OID describing the language of  `policy' .

     POLICY: uint8_t byte array with policy language, can be `NULL'

     SIZEOF_POLICY: size of  `policy' .

     This function will set the proxyCertInfo extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_proxy_dn
----------------------------

 -- Function: int gnutls_x509_crt_set_proxy_dn (gnutls_x509_crt_t CRT,
          gnutls_x509_crt_t EECRT, unsigned int RAW_FLAG, const void *
          NAME, unsigned int SIZEOF_NAME)
     CRT: a gnutls_x509_crt_t structure with the new proxy cert

     EECRT: the end entity certificate that will be issuing the proxy

     RAW_FLAG: must be 0, or 1 if the CN is DER encoded

     NAME: a pointer to the CN name, may be NULL (but MUST then be
     added later)

     SIZEOF_NAME: holds the size of  `name'

     This function will set the subject in  `crt' to the end entity's
     `eecrt' subject name, and add a single Common Name component
     `name' of size  `sizeof_name' .  This corresponds to the required
     proxy certificate naming style.  Note that if  `name' is `NULL' ,
     you MUST set it later by using `gnutls_x509_crt_set_dn_by_oid()'
     or similar.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_serial
--------------------------

 -- Function: int gnutls_x509_crt_set_serial (gnutls_x509_crt_t CERT,
          const void * SERIAL, size_t SERIAL_SIZE)
     CERT: a certificate of type `gnutls_x509_crt_t'

     SERIAL: The serial number

     SERIAL_SIZE: Holds the size of the serial field.

     This function will set the X.509 certificate's serial number.
     Serial is not always a 32 or 64bit number.  Some CAs use large
     serial numbers, thus it may be wise to handle it as something
     uint8_t.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_subject_alternative_name
--------------------------------------------

 -- Function: int gnutls_x509_crt_set_subject_alternative_name
          (gnutls_x509_crt_t CRT, gnutls_x509_subject_alt_name_t TYPE,
          const char * DATA_STRING)
     CRT: a certificate of type `gnutls_x509_crt_t'

     TYPE: is one of the gnutls_x509_subject_alt_name_t enumerations

     DATA_STRING: The data to be set, a (0) terminated string

     This function will set the subject alternative name certificate
     extension. This function assumes that data can be expressed as a
     null terminated string.

     The name of the function is unfortunate since it is incosistent
     with `gnutls_x509_crt_get_subject_alt_name()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_subject_alt_name
------------------------------------

 -- Function: int gnutls_x509_crt_set_subject_alt_name
          (gnutls_x509_crt_t CRT, gnutls_x509_subject_alt_name_t TYPE,
          const void * DATA, unsigned int DATA_SIZE, unsigned int FLAGS)
     CRT: a certificate of type `gnutls_x509_crt_t'

     TYPE: is one of the gnutls_x509_subject_alt_name_t enumerations

     DATA: The data to be set

     DATA_SIZE: The size of data to be set

     FLAGS: GNUTLS_FSAN_SET to clear previous data or
     GNUTLS_FSAN_APPEND to append.

     This function will set the subject alternative name certificate
     extension. It can set the following types:

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.6.0

gnutls_x509_crt_set_subject_key_id
----------------------------------

 -- Function: int gnutls_x509_crt_set_subject_key_id (gnutls_x509_crt_t
          CERT, const void * ID, size_t ID_SIZE)
     CERT: a certificate of type `gnutls_x509_crt_t'

     ID: The key ID

     ID_SIZE: Holds the size of the serial field.

     This function will set the X.509 certificate's subject key ID
     extension.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_version
---------------------------

 -- Function: int gnutls_x509_crt_set_version (gnutls_x509_crt_t CRT,
          unsigned int VERSION)
     CRT: a certificate of type `gnutls_x509_crt_t'

     VERSION: holds the version number. For X.509v1 certificates must
     be 1.

     This function will set the version of the certificate.  This must
     be one for X.509 version 1, and so on.  Plain certificates without
     extensions must have version set to one.

     To create well-formed certificates, you must specify version 3 if
     you use any certificate extensions.  Extensions are created by
     functions such as `gnutls_x509_crt_set_subject_alt_name()' or
     `gnutls_x509_crt_set_key_usage()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_sign
--------------------

 -- Function: int gnutls_x509_crt_sign (gnutls_x509_crt_t CRT,
          gnutls_x509_crt_t ISSUER, gnutls_x509_privkey_t ISSUER_KEY)
     CRT: a certificate of type `gnutls_x509_crt_t'

     ISSUER: is the certificate of the certificate issuer

     ISSUER_KEY: holds the issuer's private key

     This function is the same a `gnutls_x509_crt_sign2()'  with no
     flags, and SHA1 as the hash algorithm.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_sign2
---------------------

 -- Function: int gnutls_x509_crt_sign2 (gnutls_x509_crt_t CRT,
          gnutls_x509_crt_t ISSUER, gnutls_x509_privkey_t ISSUER_KEY,
          gnutls_digest_algorithm_t DIG, unsigned int FLAGS)
     CRT: a certificate of type `gnutls_x509_crt_t'

     ISSUER: is the certificate of the certificate issuer

     ISSUER_KEY: holds the issuer's private key

     DIG: The message digest to use, `GNUTLS_DIG_SHA1'  is a safe choice

     FLAGS: must be 0

     This function will sign the certificate with the issuer's private
     key, and will copy the issuer's information into the certificate.

     This must be the last step in a certificate generation since all
     the previously set parameters are now signed.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_verify
----------------------

 -- Function: int gnutls_x509_crt_verify (gnutls_x509_crt_t CERT, const
          gnutls_x509_crt_t * CA_LIST, int CA_LIST_LENGTH, unsigned int
          FLAGS, unsigned int * VERIFY)
     CERT: is the certificate to be verified

     CA_LIST: is one certificate that is considered to be trusted one

     CA_LIST_LENGTH: holds the number of CA certificate in CA_list

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     VERIFY: will hold the certificate verification output.

     This function will try to verify the given certificate and return
     its status.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_dn_deinit
---------------------

 -- Function: void gnutls_x509_dn_deinit (gnutls_x509_dn_t DN)
     DN: a DN uint8_t object pointer.

     This function deallocates the DN object as returned by
     `gnutls_x509_dn_import()' .

     *Since:* 2.4.0

gnutls_x509_dn_export
---------------------

 -- Function: int gnutls_x509_dn_export (gnutls_x509_dn_t DN,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     DN: Holds the uint8_t DN object

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a DN PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the DN to DER or PEM format.

     If the buffer provided is not long enough to hold the output, then
     * `output_data_size' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     NAME".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_dn_get_rdn_ava
--------------------------

 -- Function: int gnutls_x509_dn_get_rdn_ava (gnutls_x509_dn_t DN, int
          IRDN, int IAVA, gnutls_x509_ava_st * AVA)
     DN: input variable with uint8_t DN pointer

     IRDN: index of RDN

     IAVA: index of AVA.

     AVA: Pointer to structure which will hold output information.

     Get pointers to data within the DN.

     Note that  `ava' will contain pointers into the  `dn' structure,
     so you should not modify any data or deallocate it.  Note also
     that the DN in turn points into the original certificate
     structure, and thus you may not deallocate the certificate and
     continue to access  `dn' .

     *Returns:* Returns 0 on success, or an error code.

gnutls_x509_dn_import
---------------------

 -- Function: int gnutls_x509_dn_import (gnutls_x509_dn_t DN, const
          gnutls_datum_t * DATA)
     DN: the structure that will hold the imported DN

     DATA: should contain a DER encoded RDN sequence

     This function parses an RDN sequence and stores the result to a
     `gnutls_x509_dn_t'  structure. The structure must have been
     initialized with `gnutls_x509_dn_init()' . You may use
     `gnutls_x509_dn_get_rdn_ava()'  to decode the DN.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.4.0

gnutls_x509_dn_init
-------------------

 -- Function: int gnutls_x509_dn_init (gnutls_x509_dn_t * DN)
     DN: the object to be initialized

     This function initializes a `gnutls_x509_dn_t'  structure.

     The object returned must be deallocated using
     `gnutls_x509_dn_deinit()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.4.0

gnutls_x509_dn_oid_known
------------------------

 -- Function: int gnutls_x509_dn_oid_known (const char * OID)
     OID: holds an Object Identifier in a null terminated string

     This function will inform about known DN OIDs. This is useful since
     functions like `gnutls_x509_crt_set_dn_by_oid()'  use the
     information on known OIDs to properly encode their input. Object
     Identifiers that are not known are not encoded by these functions,
     and their input is stored directly into the ASN.1 structure. In
     that case of unknown OIDs, you have the responsibility of DER
     encoding your data.

     *Returns:* 1 on known OIDs and 0 otherwise.

gnutls_x509_dn_oid_name
-----------------------

 -- Function: const char* gnutls_x509_dn_oid_name (const char * OID,
          unsigned int FLAGS)
     OID: holds an Object Identifier in a null terminated string

     FLAGS: 0 or `GNUTLS_X509_DN_OID_' *

     This function will return the name of a known DN OID. If
     `GNUTLS_X509_DN_OID_RETURN_OID'  is specified this function will
     return the given OID if no descriptive name has been found.

     *Returns:* A null terminated string or NULL otherwise.

     *Since:* 3.0

gnutls_x509_privkey_cpy
-----------------------

 -- Function: int gnutls_x509_privkey_cpy (gnutls_x509_privkey_t DST,
          gnutls_x509_privkey_t SRC)
     DST: The destination key, which should be initialized.

     SRC: The source key

     This function will copy a private key from source to destination
     key. Destination has to be initialized.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_deinit
--------------------------

 -- Function: void gnutls_x509_privkey_deinit (gnutls_x509_privkey_t
          KEY)
     KEY: The structure to be deinitialized

     This function will deinitialize a private key structure.

gnutls_x509_privkey_export
--------------------------

 -- Function: int gnutls_x509_privkey_export (gnutls_x509_privkey_t
          KEY, gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t
          * OUTPUT_DATA_SIZE)
     KEY: Holds the key

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a private key PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the private key to a PKCS1 structure for
     RSA keys, or an integer sequence for DSA keys.  The DSA keys are in
     the same format with the parameters used by openssl.

     If the buffer provided is not long enough to hold the output, then
     * `output_data_size' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     RSA PRIVATE KEY".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_export_dsa_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_export_dsa_raw
          (gnutls_x509_privkey_t KEY, gnutls_datum_t * P,
          gnutls_datum_t * Q, gnutls_datum_t * G, gnutls_datum_t * Y,
          gnutls_datum_t * X)
     KEY: a structure that holds the DSA parameters

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     X: will hold the x

     This function will export the DSA private key's parameters found
     in the given structure. The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_export_ecc_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_export_ecc_raw
          (gnutls_x509_privkey_t KEY, gnutls_ecc_curve_t * CURVE,
          gnutls_datum_t * X, gnutls_datum_t * Y, gnutls_datum_t* K)
     KEY: a structure that holds the rsa parameters

     CURVE: will hold the curve

     X: will hold the x coordinate

     Y: will hold the y coordinate

     K: will hold the private key

     This function will export the ECC private key's parameters found
     in the given structure. The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_privkey_export_pkcs8
--------------------------------

 -- Function: int gnutls_x509_privkey_export_pkcs8
          (gnutls_x509_privkey_t KEY, gnutls_x509_crt_fmt_t FORMAT,
          const char * PASSWORD, unsigned int FLAGS, void *
          OUTPUT_DATA, size_t * OUTPUT_DATA_SIZE)
     KEY: Holds the key

     FORMAT: the format of output params. One of PEM or DER.

     PASSWORD: the password that will be used to encrypt the key.

     FLAGS: an ORed sequence of gnutls_pkcs_encrypt_flags_t

     OUTPUT_DATA: will contain a private key PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the private key to a PKCS8 structure.
     Both RSA and DSA keys can be exported. For DSA keys we use PKCS
     `11'  definitions. If the flags do not specify the encryption
     cipher, then the default 3DES (PBES2) will be used.

     The  `password' can be either ASCII or UTF-8 in the default PBES2
     encryption schemas, or ASCII for the PKCS12 schemas.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
     be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     ENCRYPTED PRIVATE KEY" or "BEGIN PRIVATE KEY" if encryption is not
     used.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_x509_privkey_export_rsa_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_export_rsa_raw
          (gnutls_x509_privkey_t KEY, gnutls_datum_t * M,
          gnutls_datum_t * E, gnutls_datum_t * D, gnutls_datum_t * P,
          gnutls_datum_t * Q, gnutls_datum_t * U)
     KEY: a structure that holds the rsa parameters

     M: will hold the modulus

     E: will hold the public exponent

     D: will hold the private exponent

     P: will hold the first prime (p)

     Q: will hold the second prime (q)

     U: will hold the coefficient

     This function will export the RSA private key's parameters found
     in the given structure. The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_export_rsa_raw2
-----------------------------------

 -- Function: int gnutls_x509_privkey_export_rsa_raw2
          (gnutls_x509_privkey_t KEY, gnutls_datum_t * M,
          gnutls_datum_t * E, gnutls_datum_t * D, gnutls_datum_t * P,
          gnutls_datum_t * Q, gnutls_datum_t * U, gnutls_datum_t * E1,
          gnutls_datum_t * E2)
     KEY: a structure that holds the rsa parameters

     M: will hold the modulus

     E: will hold the public exponent

     D: will hold the private exponent

     P: will hold the first prime (p)

     Q: will hold the second prime (q)

     U: will hold the coefficient

     E1: will hold e1 = d mod (p-1)

     E2: will hold e2 = d mod (q-1)

     This function will export the RSA private key's parameters found
     in the given structure. The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_x509_privkey_fix
-----------------------

 -- Function: int gnutls_x509_privkey_fix (gnutls_x509_privkey_t KEY)
     KEY: Holds the key

     This function will recalculate the secondary parameters in a key.
     In RSA keys, this can be the coefficient and exponent1,2.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_generate
----------------------------

 -- Function: int gnutls_x509_privkey_generate (gnutls_x509_privkey_t
          KEY, gnutls_pk_algorithm_t ALGO, unsigned int BITS, unsigned
          int FLAGS)
     KEY: should contain a `gnutls_x509_privkey_t'  structure

     ALGO: is one of the algorithms in `gnutls_pk_algorithm_t' .

     BITS: the size of the modulus

     FLAGS: unused for now.  Must be 0.

     This function will generate a random private key. Note that this
     function must be called on an empty private key.

     Do not set the number of bits directly, use
     `gnutls_sec_param_to_pk_bits()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_get_key_id
------------------------------

 -- Function: int gnutls_x509_privkey_get_key_id (gnutls_x509_privkey_t
          KEY, unsigned int FLAGS, unsigned char * OUTPUT_DATA, size_t
          * OUTPUT_DATA_SIZE)
     KEY: Holds the key

     FLAGS: should be 0 for now

     OUTPUT_DATA: will contain the key ID

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will return a unique ID the depends on the public key
     parameters. This ID can be used in checking whether a certificate
     corresponds to the given key.

     If the buffer provided is not long enough to hold the output, then
     * `output_data_size' is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.  The output will normally be a SHA-1 hash
     output, which is 20 bytes.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_get_pk_algorithm
------------------------------------

 -- Function: int gnutls_x509_privkey_get_pk_algorithm
          (gnutls_x509_privkey_t KEY)
     KEY: should contain a `gnutls_x509_privkey_t'  structure

     This function will return the public key algorithm of a private
     key.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

gnutls_x509_privkey_import
--------------------------

 -- Function: int gnutls_x509_privkey_import (gnutls_x509_privkey_t
          KEY, const gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t
          FORMAT)
     KEY: The structure to store the parsed key

     DATA: The DER or PEM encoded certificate.

     FORMAT: One of DER or PEM

     This function will convert the given DER or PEM encoded key to the
     native `gnutls_x509_privkey_t'  format. The output will be stored
     in  `key' .

     If the key is PEM encoded it should have a header of "RSA PRIVATE
     KEY", or "DSA PRIVATE KEY".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_import_dsa_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_import_dsa_raw
          (gnutls_x509_privkey_t KEY, const gnutls_datum_t * P, const
          gnutls_datum_t * Q, const gnutls_datum_t * G, const
          gnutls_datum_t * Y, const gnutls_datum_t * X)
     KEY: The structure to store the parsed key

     P: holds the p

     Q: holds the q

     G: holds the g

     Y: holds the y

     X: holds the x

     This function will convert the given DSA raw parameters to the
     native `gnutls_x509_privkey_t'  format.  The output will be stored
     in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_import_ecc_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_import_ecc_raw
          (gnutls_x509_privkey_t KEY, gnutls_ecc_curve_t CURVE, const
          gnutls_datum_t * X, const gnutls_datum_t * Y, const
          gnutls_datum_t * K)
     KEY: The structure to store the parsed key

     CURVE: holds the curve

     X: holds the x

     Y: holds the y

     K: holds the k

     This function will convert the given elliptic curve parameters to
     the native `gnutls_x509_privkey_t'  format.  The output will be
     stored in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_privkey_import_pkcs8
--------------------------------

 -- Function: int gnutls_x509_privkey_import_pkcs8
          (gnutls_x509_privkey_t KEY, const gnutls_datum_t * DATA,
          gnutls_x509_crt_fmt_t FORMAT, const char * PASSWORD, unsigned
          int FLAGS)
     KEY: The structure to store the parsed key

     DATA: The DER or PEM encoded key.

     FORMAT: One of DER or PEM

     PASSWORD: the password to decrypt the key (if it is encrypted).

     FLAGS: 0 if encrypted or GNUTLS_PKCS_PLAIN if not encrypted.

     This function will convert the given DER or PEM encoded PKCS8 2.0
     encrypted key to the native gnutls_x509_privkey_t format. The
     output will be stored in  `key' .  Both RSA and DSA keys can be
     imported, and flags can only be used to indicate an unencrypted
     key.

     The  `password' can be either ASCII or UTF-8 in the default PBES2
     encryption schemas, or ASCII for the PKCS12 schemas.

     If the Certificate is PEM encoded it should have a header of
     "ENCRYPTED PRIVATE KEY", or "PRIVATE KEY". You only need to
     specify the flags if the key is DER encoded, since in that case
     the encryption status cannot be auto-detected.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_import_rsa_raw
----------------------------------

 -- Function: int gnutls_x509_privkey_import_rsa_raw
          (gnutls_x509_privkey_t KEY, const gnutls_datum_t * M, const
          gnutls_datum_t * E, const gnutls_datum_t * D, const
          gnutls_datum_t * P, const gnutls_datum_t * Q, const
          gnutls_datum_t * U)
     KEY: The structure to store the parsed key

     M: holds the modulus

     E: holds the public exponent

     D: holds the private exponent

     P: holds the first prime (p)

     Q: holds the second prime (q)

     U: holds the coefficient

     This function will convert the given RSA raw parameters to the
     native `gnutls_x509_privkey_t'  format.  The output will be stored
     in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_import_rsa_raw2
-----------------------------------

 -- Function: int gnutls_x509_privkey_import_rsa_raw2
          (gnutls_x509_privkey_t KEY, const gnutls_datum_t * M, const
          gnutls_datum_t * E, const gnutls_datum_t * D, const
          gnutls_datum_t * P, const gnutls_datum_t * Q, const
          gnutls_datum_t * U, const gnutls_datum_t * E1, const
          gnutls_datum_t * E2)
     KEY: The structure to store the parsed key

     M: holds the modulus

     E: holds the public exponent

     D: holds the private exponent

     P: holds the first prime (p)

     Q: holds the second prime (q)

     U: holds the coefficient

     E1: holds e1 = d mod (p-1)

     E2: holds e2 = d mod (q-1)

     This function will convert the given RSA raw parameters to the
     native `gnutls_x509_privkey_t'  format.  The output will be stored
     in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_init
------------------------

 -- Function: int gnutls_x509_privkey_init (gnutls_x509_privkey_t * KEY)
     KEY: The structure to be initialized

     This function will initialize an private key structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_privkey_sec_param
-----------------------------

 -- Function: gnutls_sec_param_t gnutls_x509_privkey_sec_param
          (gnutls_x509_privkey_t KEY)
     KEY: a key structure

     This function will return the security parameter appropriate with
     this private key.

     *Returns:* On success, a valid security parameter is returned
     otherwise `GNUTLS_SEC_PARAM_UNKNOWN'  is returned.

     *Since:* 2.12.0

gnutls_x509_privkey_verify_params
---------------------------------

 -- Function: int gnutls_x509_privkey_verify_params
          (gnutls_x509_privkey_t KEY)
     KEY: should contain a `gnutls_x509_privkey_t'  structure

     This function will verify the private key parameters.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_rdn_get
-------------------

 -- Function: int gnutls_x509_rdn_get (const gnutls_datum_t * IDN, char
          * BUF, size_t * SIZEOF_BUF)
     IDN: should contain a DER encoded RDN sequence

     BUF: a pointer to a structure to hold the peer's name

     SIZEOF_BUF: holds the size of  `buf'

     This function will return the name of the given RDN sequence.  The
     name will be in the form "C=xxxx,O=yyyy,CN=zzzz" as described in
     RFC4514.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned, or
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  is returned and * `sizeof_buf' is
     updated if the provided buffer is not long enough, otherwise a
     negative error value.

gnutls_x509_rdn_get_by_oid
--------------------------

 -- Function: int gnutls_x509_rdn_get_by_oid (const gnutls_datum_t *
          IDN, const char * OID, int INDX, unsigned int RAW_FLAG, void
          * BUF, size_t * SIZEOF_BUF)
     IDN: should contain a DER encoded RDN sequence

     OID: an Object Identifier

     INDX: In case multiple same OIDs exist in the RDN indicates which
     to send. Use 0 for the first one.

     RAW_FLAG: If non (0) then the raw DER data are returned.

     BUF: a pointer to a structure to hold the peer's name

     SIZEOF_BUF: holds the size of  `buf'

     This function will return the name of the given Object identifier,
     of the RDN sequence.  The name will be encoded using the rules
     from RFC4514.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned, or
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  is returned and * `sizeof_buf' is
     updated if the provided buffer is not long enough, otherwise a
     negative error value.

gnutls_x509_rdn_get_oid
-----------------------

 -- Function: int gnutls_x509_rdn_get_oid (const gnutls_datum_t * IDN,
          int INDX, void * BUF, size_t * SIZEOF_BUF)
     IDN: should contain a DER encoded RDN sequence

     INDX: Indicates which OID to return. Use 0 for the first one.

     BUF: a pointer to a structure to hold the peer's name OID

     SIZEOF_BUF: holds the size of  `buf'

     This function will return the specified Object identifier, of the
     RDN sequence.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned, or
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  is returned and * `sizeof_buf' is
     updated if the provided buffer is not long enough, otherwise a
     negative error value.

     *Since:* 2.4.0

gnutls_x509_trust_list_add_cas
------------------------------

 -- Function: int gnutls_x509_trust_list_add_cas
          (gnutls_x509_trust_list_t LIST, const gnutls_x509_crt_t *
          CLIST, int CLIST_SIZE, unsigned int FLAGS)
     LIST: The structure of the list

     CLIST: A list of CAs

     CLIST_SIZE: The length of the CA list

     FLAGS: should be 0.

     This function will add the given certificate authorities to the
     trusted list. The list of CAs must not be deinitialized during
     this structure's lifetime.

     *Returns:* The number of added elements is returned.

     *Since:* 3.0

gnutls_x509_trust_list_add_crls
-------------------------------

 -- Function: int gnutls_x509_trust_list_add_crls
          (gnutls_x509_trust_list_t LIST, const gnutls_x509_crl_t *
          CRL_LIST, int CRL_SIZE, unsigned int FLAGS, unsigned int
          VERIFICATION_FLAGS)
     LIST: The structure of the list

     CRL_LIST: A list of CRLs

     CRL_SIZE: The length of the CRL list

     FLAGS: if GNUTLS_TL_VERIFY_CRL is given the CRLs will be verified
     before being added.

     VERIFICATION_FLAGS: gnutls_certificate_verify_flags if flags
     specifies GNUTLS_TL_VERIFY_CRL

     This function will add the given certificate revocation lists to
     the trusted list. The list of CRLs must not be deinitialized
     during this structure's lifetime.

     This function must be called after
     `gnutls_x509_trust_list_add_cas()' to allow verifying the CRLs for
     validity.

     *Returns:* The number of added elements is returned.

     *Since:* 3.0

gnutls_x509_trust_list_add_named_crt
------------------------------------

 -- Function: int gnutls_x509_trust_list_add_named_crt
          (gnutls_x509_trust_list_t LIST, gnutls_x509_crt_t CERT, const
          void * NAME, size_t NAME_SIZE, unsigned int FLAGS)
     LIST: The structure of the list

     CERT: A certificate

     NAME: An identifier for the certificate

     NAME_SIZE: The size of the identifier

     FLAGS: should be 0.

     This function will add the given certificate to the trusted list
     and associate it with a name. The certificate will not be be used
     for verification with `gnutls_x509_trust_list_verify_crt()' but
     only with `gnutls_x509_trust_list_verify_named_crt()' .

     In principle this function can be used to set individual "server"
     certificates that are trusted by the user for that specific server
     but for no other purposes.

     The certificate must not be deinitialized during the lifetime of
     the trusted list.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_trust_list_add_system_trust
---------------------------------------

 -- Function: int gnutls_x509_trust_list_add_system_trust
          (gnutls_x509_trust_list_t LIST, unsigned int TL_FLAGS,
          unsigned int TL_VFLAGS)
     LIST: The structure of the list

     TL_FLAGS: GNUTLS_TL_*

     TL_VFLAGS: gnutls_certificate_verify_flags if flags specifies
     GNUTLS_TL_VERIFY_CRL

     This function adds the system's default trusted certificate
     authorities to the trusted list.

     *Returns:* The number of added elements is returned.

     *Since:* 3.1

gnutls_x509_trust_list_add_trust_file
-------------------------------------

 -- Function: int gnutls_x509_trust_list_add_trust_file
          (gnutls_x509_trust_list_t LIST, const char* CA_FILE, const
          char* CRL_FILE, gnutls_x509_crt_fmt_t TYPE, unsigned int
          TL_FLAGS, unsigned int TL_VFLAGS)
     LIST: The structure of the list

     CA_FILE: A file containing a list of CAs (optional)

     CRL_FILE: A file containing a list of CRLs (optional)

     TYPE: The format of the certificates

     TL_FLAGS: GNUTLS_TL_*

     TL_VFLAGS: gnutls_certificate_verify_flags if flags specifies
     GNUTLS_TL_VERIFY_CRL

     This function will add the given certificate authorities to the
     trusted list. pkcs11 URLs are also accepted, instead of files, by
     this function.

     *Returns:* The number of added elements is returned.

     *Since:* 3.1

gnutls_x509_trust_list_add_trust_mem
------------------------------------

 -- Function: int gnutls_x509_trust_list_add_trust_mem
          (gnutls_x509_trust_list_t LIST, const gnutls_datum_t * CAS,
          const gnutls_datum_t * CRLS, gnutls_x509_crt_fmt_t TYPE,
          unsigned int TL_FLAGS, unsigned int TL_VFLAGS)
     LIST: The structure of the list

     CAS: - undescribed -

     CRLS: - undescribed -

     TYPE: The format of the certificates

     TL_FLAGS: GNUTLS_TL_*

     TL_VFLAGS: gnutls_certificate_verify_flags if flags specifies
     GNUTLS_TL_VERIFY_CRL

     This function will add the given certificate authorities to the
     trusted list.

     *Returns:* The number of added elements is returned.

     *Since:* 3.1

gnutls_x509_trust_list_deinit
-----------------------------

 -- Function: void gnutls_x509_trust_list_deinit
          (gnutls_x509_trust_list_t LIST, unsigned int ALL)
     LIST: The structure to be deinitialized

     ALL: if non-(0) it will deinitialize all the certificates and CRLs
     contained in the structure.

     This function will deinitialize a trust list.

     *Since:* 3.0

gnutls_x509_trust_list_get_issuer
---------------------------------

 -- Function: int gnutls_x509_trust_list_get_issuer
          (gnutls_x509_trust_list_t LIST, gnutls_x509_crt_t CERT,
          gnutls_x509_crt_t * ISSUER, unsigned int FLAGS)
     LIST: The structure of the list

     CERT: is the certificate to find issuer for

     ISSUER: Will hold the issuer if any. Should be treated as constant.

     FLAGS: Use (0).

     This function will attempt to find the issuer of the given
     certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_trust_list_init
---------------------------

 -- Function: int gnutls_x509_trust_list_init (gnutls_x509_trust_list_t
          * LIST, unsigned int SIZE)
     LIST: The structure to be initialized

     SIZE: The size of the internal hash table. Use (0) for default
     size.

     This function will initialize an X.509 trust list structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_trust_list_verify_crt
---------------------------------

 -- Function: int gnutls_x509_trust_list_verify_crt
          (gnutls_x509_trust_list_t LIST, gnutls_x509_crt_t *
          CERT_LIST, unsigned int CERT_LIST_SIZE, unsigned int FLAGS,
          unsigned int * VERIFY, gnutls_verify_output_function FUNC)
     LIST: The structure of the list

     CERT_LIST: is the certificate list to be verified

     CERT_LIST_SIZE: is the certificate list size

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     VERIFY: will hold the certificate verification output.

     FUNC: If non-null will be called on each chain element
     verification with the output.

     This function will try to verify the given certificate and return
     its status.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_x509_trust_list_verify_named_crt
---------------------------------------

 -- Function: int gnutls_x509_trust_list_verify_named_crt
          (gnutls_x509_trust_list_t LIST, gnutls_x509_crt_t CERT, const
          void * NAME, size_t NAME_SIZE, unsigned int FLAGS, unsigned
          int * VERIFY, gnutls_verify_output_function FUNC)
     LIST: The structure of the list

     CERT: is the certificate to be verified

     NAME: is the certificate's name

     NAME_SIZE: is the certificate's name size

     FLAGS: Flags that may be used to change the verification
     algorithm. Use OR of the gnutls_certificate_verify_flags
     enumerations.

     VERIFY: will hold the certificate verification output.

     FUNC: If non-null will be called on each chain element
     verification with the output.

     This function will try to find a matching named certificate. If a
     match is found the certificate is considered valid. In addition to
     that this function will also check CRLs.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0


File: gnutls.info,  Node: OCSP API,  Next: OpenPGP API,  Prev: X509 certificate API,  Up: API reference

E.4 OCSP API
============

The following functions are for OCSP certificate status checking.
Their prototypes lie in `gnutls/ocsp.h'.

gnutls_ocsp_req_add_cert
------------------------

 -- Function: int gnutls_ocsp_req_add_cert (gnutls_ocsp_req_t REQ,
          gnutls_digest_algorithm_t DIGEST, gnutls_x509_crt_t ISSUER,
          gnutls_x509_crt_t CERT)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     DIGEST: hash algorithm, a `gnutls_digest_algorithm_t'  value

     ISSUER: issuer of  `subject' certificate

     CERT: certificate to request status for

     This function will add another request to the OCSP request for a
     particular certificate.  The issuer name hash, issuer key hash, and
     serial number fields is populated as follows.  The issuer name and
     the serial number is taken from  `cert' .  The issuer key is taken
     from  `issuer' .  The hashed values will be hashed using the
     `digest' algorithm, normally `GNUTLS_DIG_SHA1' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_req_add_cert_id
---------------------------

 -- Function: int gnutls_ocsp_req_add_cert_id (gnutls_ocsp_req_t REQ,
          gnutls_digest_algorithm_t DIGEST, const gnutls_datum_t *
          ISSUER_NAME_HASH, const gnutls_datum_t * ISSUER_KEY_HASH,
          const gnutls_datum_t * SERIAL_NUMBER)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     DIGEST: hash algorithm, a `gnutls_digest_algorithm_t'  value

     ISSUER_NAME_HASH: hash of issuer's DN

     ISSUER_KEY_HASH: hash of issuer's public key

     SERIAL_NUMBER: serial number of certificate to check

     This function will add another request to the OCSP request for a
     particular certificate having the issuer name hash of
     `issuer_name_hash' and issuer key hash of  `issuer_key_hash' (both
     hashed using  `digest' ) and serial number  `serial_number' .

     The information needed corresponds to the CertID structure:

     <informalexample><programlisting> CertID          ::=     SEQUENCE
     { hashAlgorithm       AlgorithmIdentifier, issuerNameHash
     OCTET STRING, - Hash of Issuer's DN issuerKeyHash       OCTET
     STRING, - Hash of Issuers public key serialNumber
     CertificateSerialNumber } </programlisting></informalexample>

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_req_deinit
----------------------

 -- Function: void gnutls_ocsp_req_deinit (gnutls_ocsp_req_t REQ)
     REQ: The structure to be deinitialized

     This function will deinitialize a OCSP request structure.

gnutls_ocsp_req_export
----------------------

 -- Function: int gnutls_ocsp_req_export (gnutls_ocsp_req_t REQ,
          gnutls_datum_t * DATA)
     REQ: Holds the OCSP request

     DATA: newly allocate buffer holding DER encoded OCSP request

     This function will export the OCSP request to DER format.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_ocsp_req_get_cert_id
---------------------------

 -- Function: int gnutls_ocsp_req_get_cert_id (gnutls_ocsp_req_t REQ,
          unsigned INDX, gnutls_digest_algorithm_t * DIGEST,
          gnutls_datum_t * ISSUER_NAME_HASH, gnutls_datum_t *
          ISSUER_KEY_HASH, gnutls_datum_t * SERIAL_NUMBER)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     INDX: Specifies which extension OID to get. Use (0) to get the
     first one.

     DIGEST: output variable with `gnutls_digest_algorithm_t'  hash
     algorithm

     ISSUER_NAME_HASH: output buffer with hash of issuer's DN

     ISSUER_KEY_HASH: output buffer with hash of issuer's public key

     SERIAL_NUMBER: output buffer with serial number of certificate to
     check

     This function will return the certificate information of the
     `indx' 'ed request in the OCSP request.  The information returned
     corresponds to the CertID structure:

     <informalexample><programlisting> CertID          ::=     SEQUENCE
     { hashAlgorithm       AlgorithmIdentifier, issuerNameHash
     OCTET STRING, - Hash of Issuer's DN issuerKeyHash       OCTET
     STRING, - Hash of Issuers public key serialNumber
     CertificateSerialNumber } </programlisting></informalexample>

     Each of the pointers to output variables may be NULL to indicate
     that the caller is not interested in that value.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last CertID available `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'
     will be returned.

gnutls_ocsp_req_get_extension
-----------------------------

 -- Function: int gnutls_ocsp_req_get_extension (gnutls_ocsp_req_t REQ,
          unsigned INDX, gnutls_datum_t * OID, unsigned int * CRITICAL,
          gnutls_datum_t * DATA)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     INDX: Specifies which extension OID to get. Use (0) to get the
     first one.

     OID: will hold newly allocated buffer with OID of extension, may
     be NULL

     CRITICAL: output variable with critical flag, may be NULL.

     DATA: will hold newly allocated buffer with extension data, may be
     NULL

     This function will return all information about the requested
     extension in the OCSP request.  The information returned is the
     OID, the critical flag, and the data itself.  The extension OID
     will be stored as a string.  Any of  `oid' ,  `critical' , and
     `data' may be NULL which means that the caller is not interested
     in getting that information back.

     The caller needs to deallocate memory by calling `gnutls_free()'
     on  `oid' ->data and  `data' ->data.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

gnutls_ocsp_req_get_nonce
-------------------------

 -- Function: int gnutls_ocsp_req_get_nonce (gnutls_ocsp_req_t REQ,
          unsigned int * CRITICAL, gnutls_datum_t * NONCE)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     CRITICAL: whether nonce extension is marked critical, or NULL

     NONCE: will hold newly allocated buffer with nonce data

     This function will return the OCSP request nonce extension data.

     The caller needs to deallocate memory by calling `gnutls_free()'
     on  `nonce' ->data.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_req_get_version
---------------------------

 -- Function: int gnutls_ocsp_req_get_version (gnutls_ocsp_req_t REQ)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     This function will return the version of the OCSP request.
     Typically this is always 1 indicating version 1.

     *Returns:* version of OCSP request, or a negative error code on
     error.

gnutls_ocsp_req_import
----------------------

 -- Function: int gnutls_ocsp_req_import (gnutls_ocsp_req_t REQ, const
          gnutls_datum_t * DATA)
     REQ: The structure to store the parsed request.

     DATA: DER encoded OCSP request.

     This function will convert the given DER encoded OCSP request to
     the native `gnutls_ocsp_req_t'  format. The output will be stored
     in  `req' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_req_init
--------------------

 -- Function: int gnutls_ocsp_req_init (gnutls_ocsp_req_t * REQ)
     REQ: The structure to be initialized

     This function will initialize an OCSP request structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_req_print
---------------------

 -- Function: int gnutls_ocsp_req_print (gnutls_ocsp_req_t REQ,
          gnutls_ocsp_print_formats_t FORMAT, gnutls_datum_t * OUT)
     REQ: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print a OCSP request, suitable for
     display to a human.

     If the format is `GNUTLS_PRINT_FULL'  then all fields of the
     request will be output, on multiple lines.

     The output  `out' ->data needs to be deallocate using
     `gnutls_free()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_req_randomize_nonce
-------------------------------

 -- Function: int gnutls_ocsp_req_randomize_nonce (gnutls_ocsp_req_t
          REQ)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     This function will add or update an nonce extension to the OCSP
     request with a newly generated random value.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_req_set_extension
-----------------------------

 -- Function: int gnutls_ocsp_req_set_extension (gnutls_ocsp_req_t REQ,
          const char * OID, unsigned int CRITICAL, const gnutls_datum_t
          * DATA)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     OID: buffer with OID of extension as a string.

     CRITICAL: critical flag, normally false.

     DATA: the extension data

     This function will add an extension to the OCSP request.  Calling
     this function multiple times for the same OID will overwrite values
     from earlier calls.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_req_set_nonce
-------------------------

 -- Function: int gnutls_ocsp_req_set_nonce (gnutls_ocsp_req_t REQ,
          unsigned int CRITICAL, const gnutls_datum_t * NONCE)
     REQ: should contain a `gnutls_ocsp_req_t'  structure

     CRITICAL: critical flag, normally false.

     NONCE: the nonce data

     This function will add an nonce extension to the OCSP request.
     Calling this function multiple times will overwrite values from
     earlier calls.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_resp_deinit
-----------------------

 -- Function: void gnutls_ocsp_resp_deinit (gnutls_ocsp_resp_t RESP)
     RESP: The structure to be deinitialized

     This function will deinitialize a OCSP response structure.

gnutls_ocsp_resp_export
-----------------------

 -- Function: int gnutls_ocsp_resp_export (gnutls_ocsp_resp_t RESP,
          gnutls_datum_t * DATA)
     RESP: Holds the OCSP response

     DATA: newly allocate buffer holding DER encoded OCSP response

     This function will export the OCSP response to DER format.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_ocsp_resp_get_certs
--------------------------

 -- Function: int gnutls_ocsp_resp_get_certs (gnutls_ocsp_resp_t RESP,
          gnutls_x509_crt_t ** CERTS, size_t * NCERTS)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     CERTS: newly allocated array with `gnutls_x509_crt_t'  certificates

     NCERTS: output variable with number of allocated certs.

     This function will extract the X.509 certificates found in the
     Basic OCSP Response.  The  `certs' output variable will hold a
     newly allocated zero-terminated array with X.509 certificates.

     Every certificate in the array needs to be de-allocated with
     `gnutls_x509_crt_deinit()'  and the array itself must be freed
     using `gnutls_free()' .

     Both the  `certs' and  `ncerts' variables may be NULL.  Then the
     function will work as normal but will not return the NULL:d
     information.  This can be used to get the number of certificates
     only, or to just get the certificate array without its size.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_get_extension
------------------------------

 -- Function: int gnutls_ocsp_resp_get_extension (gnutls_ocsp_resp_t
          RESP, unsigned INDX, gnutls_datum_t * OID, unsigned int *
          CRITICAL, gnutls_datum_t * DATA)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     INDX: Specifies which extension OID to get. Use (0) to get the
     first one.

     OID: will hold newly allocated buffer with OID of extension, may
     be NULL

     CRITICAL: output variable with critical flag, may be NULL.

     DATA: will hold newly allocated buffer with extension data, may be
     NULL

     This function will return all information about the requested
     extension in the OCSP response.  The information returned is the
     OID, the critical flag, and the data itself.  The extension OID
     will be stored as a string.  Any of  `oid' ,  `critical' , and
     `data' may be NULL which means that the caller is not interested
     in getting that information back.

     The caller needs to deallocate memory by calling `gnutls_free()'
     on  `oid' ->data and  `data' ->data.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last extension available
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

gnutls_ocsp_resp_get_nonce
--------------------------

 -- Function: int gnutls_ocsp_resp_get_nonce (gnutls_ocsp_resp_t RESP,
          unsigned int * CRITICAL, gnutls_datum_t * NONCE)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     CRITICAL: whether nonce extension is marked critical

     NONCE: will hold newly allocated buffer with nonce data

     This function will return the Basic OCSP Response nonce extension
     data.

     The caller needs to deallocate memory by calling `gnutls_free()'
     on  `nonce' ->data.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_resp_get_produced
-----------------------------

 -- Function: time_t gnutls_ocsp_resp_get_produced (gnutls_ocsp_resp_t
          RESP)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     This function will return the time when the OCSP response was
     signed.

     *Returns:* signing time, or (time_t)-1 on error.

gnutls_ocsp_resp_get_responder
------------------------------

 -- Function: int gnutls_ocsp_resp_get_responder (gnutls_ocsp_resp_t
          RESP, gnutls_datum_t * DN)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     DN: newly allocated buffer with name

     This function will extract the name of the Basic OCSP Response in
     the provided buffer. The name will be in the form
     "C=xxxx,O=yyyy,CN=zzzz" as described in RFC2253. The output string
     will be ASCII or UTF-8 encoded, depending on the certificate data.

     The caller needs to deallocate memory by calling `gnutls_free()'
     on  `dn' ->data.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_ocsp_resp_get_response
-----------------------------

 -- Function: int gnutls_ocsp_resp_get_response (gnutls_ocsp_resp_t
          RESP, gnutls_datum_t * RESPONSE_TYPE_OID, gnutls_datum_t *
          RESPONSE)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     RESPONSE_TYPE_OID: newly allocated output buffer with response
     type OID

     RESPONSE: newly allocated output buffer with DER encoded response

     This function will extract the response type OID in and the
     response data from an OCSP response.  Normally the
     `response_type_oid' is always "1.3.6.1.5.5.7.48.1.1" which means
     the  `response' should be decoded as a Basic OCSP Response, but
     technically other response types could be used.

     This function is typically only useful when you want to extract the
     response type OID of an response for diagnostic purposes.
     Otherwise `gnutls_ocsp_resp_import()'  will decode the basic OCSP
     response part and the caller need not worry about that aspect.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_get_signature
------------------------------

 -- Function: int gnutls_ocsp_resp_get_signature (gnutls_ocsp_resp_t
          RESP, gnutls_datum_t * SIG)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     SIG: newly allocated output buffer with signature data

     This function will extract the signature field of a OCSP response.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_get_signature_algorithm
----------------------------------------

 -- Function: int gnutls_ocsp_resp_get_signature_algorithm
          (gnutls_ocsp_resp_t RESP)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     This function will return a value of the `gnutls_sign_algorithm_t'
     enumeration that is the signature algorithm that has been used to
     sign the OCSP response.

     *Returns:* a `gnutls_sign_algorithm_t'  value, or a negative error
     code on error.

gnutls_ocsp_resp_get_single
---------------------------

 -- Function: int gnutls_ocsp_resp_get_single (gnutls_ocsp_resp_t RESP,
          unsigned INDX, gnutls_digest_algorithm_t * DIGEST,
          gnutls_datum_t * ISSUER_NAME_HASH, gnutls_datum_t *
          ISSUER_KEY_HASH, gnutls_datum_t * SERIAL_NUMBER, unsigned int
          * CERT_STATUS, time_t * THIS_UPDATE, time_t * NEXT_UPDATE,
          time_t * REVOCATION_TIME, unsigned int * REVOCATION_REASON)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     INDX: Specifies which extension OID to get. Use (0) to get the
     first one.

     DIGEST: output variable with `gnutls_digest_algorithm_t'  hash
     algorithm

     ISSUER_NAME_HASH: output buffer with hash of issuer's DN

     ISSUER_KEY_HASH: output buffer with hash of issuer's public key

     SERIAL_NUMBER: output buffer with serial number of certificate to
     check

     CERT_STATUS: a certificate status, a `gnutls_ocsp_cert_status_t'
     enum.

     THIS_UPDATE: time at which the status is known to be correct.

     NEXT_UPDATE: when newer information will be available, or
     (time_t)-1 if unspecified

     REVOCATION_TIME: when  `cert_status' is `GNUTLS_OCSP_CERT_REVOKED'
     , holds time of revocation.

     REVOCATION_REASON: revocation reason, a `gnutls_x509_crl_reason_t'
     enum.

     This function will return the certificate information of the
     `indx' 'ed response in the Basic OCSP Response  `resp' .  The
     information returned corresponds to the SingleResponse structure
     except the final singleExtensions, reproduced here for
     illustration:

     <informalexample><programlisting> SingleResponse ::= SEQUENCE {
     certID                       CertID, certStatus
     CertStatus, thisUpdate                   GeneralizedTime,
     nextUpdate         [0]       EXPLICIT GeneralizedTime OPTIONAL,
     singleExtensions   [1]       EXPLICIT Extensions OPTIONAL }

     CertID          ::=     SEQUENCE { hashAlgorithm
     AlgorithmIdentifier, issuerNameHash      OCTET STRING, - Hash of
     Issuer's DN issuerKeyHash       OCTET STRING, - Hash of Issuers
     public key serialNumber        CertificateSerialNumber }

     CertStatus ::= CHOICE { good                [0]     IMPLICIT NULL,
     revoked             [1]     IMPLICIT RevokedInfo, unknown
       [2]     IMPLICIT UnknownInfo }

     RevokedInfo ::= SEQUENCE { revocationTime
     GeneralizedTime, revocationReason    [0]     EXPLICIT CRLReason
     OPTIONAL } </programlisting></informalexample>

     Each of the pointers to output variables may be NULL to indicate
     that the caller is not interested in that value.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.  If you have reached
     the last CertID available `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'
     will be returned.

gnutls_ocsp_resp_get_status
---------------------------

 -- Function: int gnutls_ocsp_resp_get_status (gnutls_ocsp_resp_t RESP)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     This function will return the status of a OCSP response, an
     `gnutls_ocsp_resp_status_t'  enumeration.

     *Returns:* status of OCSP request as a `gnutls_ocsp_resp_status_t'
     , or a negative error code on error.

gnutls_ocsp_resp_get_version
----------------------------

 -- Function: int gnutls_ocsp_resp_get_version (gnutls_ocsp_resp_t RESP)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     This function will return the version of the Basic OCSP Response.
     Typically this is always 1 indicating version 1.

     *Returns:* version of Basic OCSP response, or a negative error code
     on error.

gnutls_ocsp_resp_import
-----------------------

 -- Function: int gnutls_ocsp_resp_import (gnutls_ocsp_resp_t RESP,
          const gnutls_datum_t * DATA)
     RESP: The structure to store the parsed response.

     DATA: DER encoded OCSP response.

     This function will convert the given DER encoded OCSP response to
     the native `gnutls_ocsp_resp_t'  format.  It also decodes the Basic
     OCSP Response part, if any.  The output will be stored in  `resp' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_init
---------------------

 -- Function: int gnutls_ocsp_resp_init (gnutls_ocsp_resp_t * RESP)
     RESP: The structure to be initialized

     This function will initialize an OCSP response structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_print
----------------------

 -- Function: int gnutls_ocsp_resp_print (gnutls_ocsp_resp_t RESP,
          gnutls_ocsp_print_formats_t FORMAT, gnutls_datum_t * OUT)
     RESP: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print a OCSP response, suitable for
     display to a human.

     If the format is `GNUTLS_PRINT_FULL'  then all fields of the
     response will be output, on multiple lines.

     The output  `out' ->data needs to be deallocate using
     `gnutls_free()' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_verify
-----------------------

 -- Function: int gnutls_ocsp_resp_verify (gnutls_ocsp_resp_t RESP,
          gnutls_x509_trust_list_t TRUSTLIST, unsigned int * VERIFY,
          unsigned int FLAGS)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     TRUSTLIST: trust anchors as a `gnutls_x509_trust_list_t'  structure

     VERIFY: output variable with verification status, an
     `gnutls_ocsp_cert_status_t'

     FLAGS: verification flags, 0 for now.

     Verify signature of the Basic OCSP Response against the public key
     in the certificate of a trusted signer.  The  `trustlist' should be
     populated with trust anchors.  The function will extract the signer
     certificate from the Basic OCSP Response and will verify it against
     the  `trustlist' .  A trusted signer is a certificate that is
     either in  `trustlist' , or it is signed directly by a certificate
     in  `trustlist' and has the id-ad-ocspSigning Extended Key Usage
     bit set.

     The output  `verify' variable will hold verification status codes
     (e.g., `GNUTLS_OCSP_VERIFY_SIGNER_NOT_FOUND' ,
     `GNUTLS_OCSP_VERIFY_INSECURE_ALGORITHM' ) which are only valid if
     the function returned `GNUTLS_E_SUCCESS' .

     Note that the function returns `GNUTLS_E_SUCCESS'  even when
     verification failed.  The caller must always inspect the  `verify'
     variable to find out the verification status.

     The  `flags' variable should be 0 for now.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_ocsp_resp_verify_direct
------------------------------

 -- Function: int gnutls_ocsp_resp_verify_direct (gnutls_ocsp_resp_t
          RESP, gnutls_x509_crt_t ISSUER, unsigned int * VERIFY,
          unsigned int FLAGS)
     RESP: should contain a `gnutls_ocsp_resp_t'  structure

     ISSUER: certificate believed to have signed the response

     VERIFY: output variable with verification status, an
     `gnutls_ocsp_cert_status_t'

     FLAGS: verification flags, 0 for now.

     Verify signature of the Basic OCSP Response against the public key
     in the  `issuer' certificate.

     The output  `verify' variable will hold verification status codes
     (e.g., `GNUTLS_OCSP_VERIFY_SIGNER_NOT_FOUND' ,
     `GNUTLS_OCSP_VERIFY_INSECURE_ALGORITHM' ) which are only valid if
     the function returned `GNUTLS_E_SUCCESS' .

     Note that the function returns `GNUTLS_E_SUCCESS'  even when
     verification failed.  The caller must always inspect the  `verify'
     variable to find out the verification status.

     The  `flags' variable should be 0 for now.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.


File: gnutls.info,  Node: OpenPGP API,  Next: PKCS 12 API,  Prev: OCSP API,  Up: API reference

E.5 OpenPGP API
===============

The following functions are to be used for OpenPGP certificate
handling.  Their prototypes lie in `gnutls/openpgp.h'.

gnutls_certificate_set_openpgp_key
----------------------------------

 -- Function: int gnutls_certificate_set_openpgp_key
          (gnutls_certificate_credentials_t RES, gnutls_openpgp_crt_t
          CRT, gnutls_openpgp_privkey_t PKEY)
     RES: is a `gnutls_certificate_credentials_t'  structure.

     CRT: contains an openpgp public key

     PKEY: is an openpgp private key

     This function sets a certificate/private key pair in the
     gnutls_certificate_credentials_t structure.  This function may be
     called more than once (in case multiple keys/certificates exist
     for the server).

     Note that this function requires that the preferred key ids have
     been set and be used. See
     `gnutls_openpgp_crt_set_preferred_key_id()' .  Otherwise the
     master key will be used.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_certificate_set_openpgp_key_file
---------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_key_file
          (gnutls_certificate_credentials_t RES, const char * CERTFILE,
          const char * KEYFILE, gnutls_openpgp_crt_fmt_t FORMAT)
     RES: the destination context to save the data.

     CERTFILE: the file that contains the public key.

     KEYFILE: the file that contains the secret key.

     FORMAT: the format of the keys

     This funtion is used to load OpenPGP keys into the GnuTLS
     credentials structure. The file should contain at least one valid
     non encrypted subkey.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_certificate_set_openpgp_key_file2
----------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_key_file2
          (gnutls_certificate_credentials_t RES, const char * CERTFILE,
          const char * KEYFILE, const char * SUBKEY_ID,
          gnutls_openpgp_crt_fmt_t FORMAT)
     RES: the destination context to save the data.

     CERTFILE: the file that contains the public key.

     KEYFILE: the file that contains the secret key.

     SUBKEY_ID: a hex encoded subkey id

     FORMAT: the format of the keys

     This funtion is used to load OpenPGP keys into the GnuTLS
     credential structure. The file should contain at least one valid
     non encrypted subkey.

     The special keyword "auto" is also accepted as  `subkey_id' .  In
     that case the `gnutls_openpgp_crt_get_auth_subkey()'  will be used
     to retrieve the subkey.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.4.0

gnutls_certificate_set_openpgp_key_mem
--------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_key_mem
          (gnutls_certificate_credentials_t RES, const gnutls_datum_t *
          CERT, const gnutls_datum_t * KEY, gnutls_openpgp_crt_fmt_t
          FORMAT)
     RES: the destination context to save the data.

     CERT: the datum that contains the public key.

     KEY: the datum that contains the secret key.

     FORMAT: the format of the keys

     This funtion is used to load OpenPGP keys into the GnuTLS
     credential structure. The datum should contain at least one valid
     non encrypted subkey.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_certificate_set_openpgp_key_mem2
---------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_key_mem2
          (gnutls_certificate_credentials_t RES, const gnutls_datum_t *
          CERT, const gnutls_datum_t * KEY, const char * SUBKEY_ID,
          gnutls_openpgp_crt_fmt_t FORMAT)
     RES: the destination context to save the data.

     CERT: the datum that contains the public key.

     KEY: the datum that contains the secret key.

     SUBKEY_ID: a hex encoded subkey id

     FORMAT: the format of the keys

     This funtion is used to load OpenPGP keys into the GnuTLS
     credentials structure. The datum should contain at least one valid
     non encrypted subkey.

     The special keyword "auto" is also accepted as  `subkey_id' .  In
     that case the `gnutls_openpgp_crt_get_auth_subkey()'  will be used
     to retrieve the subkey.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.4.0

gnutls_certificate_set_openpgp_keyring_file
-------------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_keyring_file
          (gnutls_certificate_credentials_t C, const char * FILE,
          gnutls_openpgp_crt_fmt_t FORMAT)
     C: A certificate credentials structure

     FILE: filename of the keyring.

     FORMAT: format of keyring.

     The function is used to set keyrings that will be used internally
     by various OpenPGP functions. For example to find a key when it is
     needed for an operations. The keyring will also be used at the
     verification functions.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_certificate_set_openpgp_keyring_mem
------------------------------------------

 -- Function: int gnutls_certificate_set_openpgp_keyring_mem
          (gnutls_certificate_credentials_t C, const uint8_t * DATA,
          size_t DLEN, gnutls_openpgp_crt_fmt_t FORMAT)
     C: A certificate credentials structure

     DATA: buffer with keyring data.

     DLEN: length of data buffer.

     FORMAT: the format of the keyring

     The function is used to set keyrings that will be used internally
     by various OpenPGP functions. For example to find a key when it is
     needed for an operations. The keyring will also be used at the
     verification functions.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_openpgp_crt_check_hostname
---------------------------------

 -- Function: int gnutls_openpgp_crt_check_hostname
          (gnutls_openpgp_crt_t KEY, const char * HOSTNAME)
     KEY: should contain a `gnutls_openpgp_crt_t'  structure

     HOSTNAME: A null terminated string that contains a DNS name

     This function will check if the given key's owner matches the
     given hostname. This is a basic implementation of the matching
     described in RFC2818 (HTTPS), which takes into account wildcards.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_deinit
-------------------------

 -- Function: void gnutls_openpgp_crt_deinit (gnutls_openpgp_crt_t KEY)
     KEY: The structure to be initialized

     This function will deinitialize a key structure.

gnutls_openpgp_crt_export
-------------------------

 -- Function: int gnutls_openpgp_crt_export (gnutls_openpgp_crt_t KEY,
          gnutls_openpgp_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     KEY: Holds the key.

     FORMAT: One of gnutls_openpgp_crt_fmt_t elements.

     OUTPUT_DATA: will contain the key base64 encoded or raw

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will convert the given key to RAW or Base64 format.
     If the buffer provided is not long enough to hold the output, then
     `GNUTLS_E_SHORT_MEMORY_BUFFER'  will be returned.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_get_auth_subkey
----------------------------------

 -- Function: int gnutls_openpgp_crt_get_auth_subkey
          (gnutls_openpgp_crt_t CRT, gnutls_openpgp_keyid_t KEYID,
          unsigned int FLAG)
     CRT: the structure that contains the OpenPGP public key.

     KEYID: the struct to save the keyid.

     FLAG: Non (0) indicates that a valid subkey is always returned.

     Returns the 64-bit keyID of the first valid OpenPGP subkey marked
     for authentication.  If flag is non (0) and no authentication
     subkey exists, then a valid subkey will be returned even if it is
     not marked for authentication.  Returns the 64-bit keyID of the
     first valid OpenPGP subkey marked for authentication.  If flag is
     non (0) and no authentication subkey exists, then a valid subkey
     will be returned even if it is not marked for authentication.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_get_creation_time
------------------------------------

 -- Function: time_t gnutls_openpgp_crt_get_creation_time
          (gnutls_openpgp_crt_t KEY)
     KEY: the structure that contains the OpenPGP public key.

     Get key creation time.

     *Returns:* the timestamp when the OpenPGP key was created.

gnutls_openpgp_crt_get_expiration_time
--------------------------------------

 -- Function: time_t gnutls_openpgp_crt_get_expiration_time
          (gnutls_openpgp_crt_t KEY)
     KEY: the structure that contains the OpenPGP public key.

     Get key expiration time.  A value of '0' means that the key doesn't
     expire at all.

     *Returns:* the time when the OpenPGP key expires.

gnutls_openpgp_crt_get_fingerprint
----------------------------------

 -- Function: int gnutls_openpgp_crt_get_fingerprint
          (gnutls_openpgp_crt_t KEY, void * FPR, size_t * FPRLEN)
     KEY: the raw data that contains the OpenPGP public key.

     FPR: the buffer to save the fingerprint, must hold at least 20
     bytes.

     FPRLEN: the integer to save the length of the fingerprint.

     Get key fingerprint.  Depending on the algorithm, the fingerprint
     can be 16 or 20 bytes.

     *Returns:* On success, 0 is returned.  Otherwise, an error code.

gnutls_openpgp_crt_get_key_id
-----------------------------

 -- Function: int gnutls_openpgp_crt_get_key_id (gnutls_openpgp_crt_t
          KEY, gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the buffer to save the keyid.

     Get key id string.

     *Returns:* the 64-bit keyID of the OpenPGP key.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_key_usage
--------------------------------

 -- Function: int gnutls_openpgp_crt_get_key_usage
          (gnutls_openpgp_crt_t KEY, unsigned int * KEY_USAGE)
     KEY: should contain a gnutls_openpgp_crt_t structure

     KEY_USAGE: where the key usage bits will be stored

     This function will return certificate's key usage, by checking the
     key algorithm. The key usage value will ORed values of the:
     `GNUTLS_KEY_DIGITAL_SIGNATURE' , `GNUTLS_KEY_KEY_ENCIPHERMENT' .

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_get_name
---------------------------

 -- Function: int gnutls_openpgp_crt_get_name (gnutls_openpgp_crt_t
          KEY, int IDX, char * BUF, size_t * SIZEOF_BUF)
     KEY: the structure that contains the OpenPGP public key.

     IDX: the index of the ID to extract

     BUF: a pointer to a structure to hold the name, may be `NULL' to
     only get the  `sizeof_buf' .

     SIZEOF_BUF: holds the maximum size of  `buf' , on return hold the
     actual/required size of  `buf' .

     Extracts the userID from the parsed OpenPGP key.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, and if the index of the
     ID does not exist `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE' , or an
     error code.

gnutls_openpgp_crt_get_pk_algorithm
-----------------------------------

 -- Function: gnutls_pk_algorithm_t gnutls_openpgp_crt_get_pk_algorithm
          (gnutls_openpgp_crt_t KEY, unsigned int * BITS)
     KEY: is an OpenPGP key

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of an OpenPGP
     certificate.

     If bits is non null, it should have enough size to hold the
     parameters size in bits. For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or GNUTLS_PK_UNKNOWN on error.

gnutls_openpgp_crt_get_pk_dsa_raw
---------------------------------

 -- Function: int gnutls_openpgp_crt_get_pk_dsa_raw
          (gnutls_openpgp_crt_t CRT, gnutls_datum_t * P, gnutls_datum_t
          * Q, gnutls_datum_t * G, gnutls_datum_t * Y)
     CRT: Holds the certificate

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     This function will export the DSA public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_pk_rsa_raw
---------------------------------

 -- Function: int gnutls_openpgp_crt_get_pk_rsa_raw
          (gnutls_openpgp_crt_t CRT, gnutls_datum_t * M, gnutls_datum_t
          * E)
     CRT: Holds the certificate

     M: will hold the modulus

     E: will hold the public exponent

     This function will export the RSA public key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_preferred_key_id
---------------------------------------

 -- Function: int gnutls_openpgp_crt_get_preferred_key_id
          (gnutls_openpgp_crt_t KEY, gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the struct to save the keyid.

     Get preferred key id.  If it hasn't been set it returns
     `GNUTLS_E_INVALID_REQUEST' .

     *Returns:* the 64-bit preferred keyID of the OpenPGP key.

gnutls_openpgp_crt_get_revoked_status
-------------------------------------

 -- Function: int gnutls_openpgp_crt_get_revoked_status
          (gnutls_openpgp_crt_t KEY)
     KEY: the structure that contains the OpenPGP public key.

     Get revocation status of key.

     *Returns:* true (1) if the key has been revoked, or false (0) if it
     has not.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_count
-----------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_count
          (gnutls_openpgp_crt_t KEY)
     KEY: is an OpenPGP key

     This function will return the number of subkeys present in the
     given OpenPGP certificate.

     *Returns:* the number of subkeys, or a negative error code on
     error.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_creation_time
-------------------------------------------

 -- Function: time_t gnutls_openpgp_crt_get_subkey_creation_time
          (gnutls_openpgp_crt_t KEY, unsigned int IDX)
     KEY: the structure that contains the OpenPGP public key.

     IDX: the subkey index

     Get subkey creation time.

     *Returns:* the timestamp when the OpenPGP sub-key was created.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_expiration_time
---------------------------------------------

 -- Function: time_t gnutls_openpgp_crt_get_subkey_expiration_time
          (gnutls_openpgp_crt_t KEY, unsigned int IDX)
     KEY: the structure that contains the OpenPGP public key.

     IDX: the subkey index

     Get subkey expiration time.  A value of '0' means that the key
     doesn't expire at all.

     *Returns:* the time when the OpenPGP key expires.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_fingerprint
-----------------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_fingerprint
          (gnutls_openpgp_crt_t KEY, unsigned int IDX, void * FPR,
          size_t * FPRLEN)
     KEY: the raw data that contains the OpenPGP public key.

     IDX: the subkey index

     FPR: the buffer to save the fingerprint, must hold at least 20
     bytes.

     FPRLEN: the integer to save the length of the fingerprint.

     Get key fingerprint of a subkey.  Depending on the algorithm, the
     fingerprint can be 16 or 20 bytes.

     *Returns:* On success, 0 is returned.  Otherwise, an error code.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_id
--------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_id
          (gnutls_openpgp_crt_t KEY, unsigned int IDX,
          gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     IDX: the subkey index

     KEYID: the buffer to save the keyid.

     Get the subkey's key-id.

     *Returns:* the 64-bit keyID of the OpenPGP key.

gnutls_openpgp_crt_get_subkey_idx
---------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_idx
          (gnutls_openpgp_crt_t KEY, const gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the keyid.

     Get subkey's index.

     *Returns:* the index of the subkey or a negative error value.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_pk_algorithm
------------------------------------------

 -- Function: gnutls_pk_algorithm_t
gnutls_openpgp_crt_get_subkey_pk_algorithm (gnutls_openpgp_crt_t KEY,
          unsigned int IDX, unsigned int * BITS)
     KEY: is an OpenPGP key

     IDX: is the subkey index

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of a subkey of
     an OpenPGP certificate.

     If bits is non null, it should have enough size to hold the
     parameters size in bits.  For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or GNUTLS_PK_UNKNOWN on error.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_pk_dsa_raw
----------------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_pk_dsa_raw
          (gnutls_openpgp_crt_t CRT, unsigned int IDX, gnutls_datum_t *
          P, gnutls_datum_t * Q, gnutls_datum_t * G, gnutls_datum_t * Y)
     CRT: Holds the certificate

     IDX: Is the subkey index

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     This function will export the DSA public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_pk_rsa_raw
----------------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_pk_rsa_raw
          (gnutls_openpgp_crt_t CRT, unsigned int IDX, gnutls_datum_t *
          M, gnutls_datum_t * E)
     CRT: Holds the certificate

     IDX: Is the subkey index

     M: will hold the modulus

     E: will hold the public exponent

     This function will export the RSA public key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_revoked_status
--------------------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_revoked_status
          (gnutls_openpgp_crt_t KEY, unsigned int IDX)
     KEY: the structure that contains the OpenPGP public key.

     IDX: is the subkey index

     Get subkey revocation status.  A negative error code indicates an
     error.

     *Returns:* true (1) if the key has been revoked, or false (0) if it
     has not.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_subkey_usage
-----------------------------------

 -- Function: int gnutls_openpgp_crt_get_subkey_usage
          (gnutls_openpgp_crt_t KEY, unsigned int IDX, unsigned int *
          KEY_USAGE)
     KEY: should contain a gnutls_openpgp_crt_t structure

     IDX: the subkey index

     KEY_USAGE: where the key usage bits will be stored

     This function will return certificate's key usage, by checking the
     key algorithm.  The key usage value will ORed values of
     `GNUTLS_KEY_DIGITAL_SIGNATURE'  or `GNUTLS_KEY_KEY_ENCIPHERMENT' .

     A negative error code may be returned in case of parsing error.

     *Returns:* key usage value.

     *Since:* 2.4.0

gnutls_openpgp_crt_get_version
------------------------------

 -- Function: int gnutls_openpgp_crt_get_version (gnutls_openpgp_crt_t
          KEY)
     KEY: the structure that contains the OpenPGP public key.

     Extract the version of the OpenPGP key.

     *Returns:* the version number is returned, or a negative error
     code on errors.

gnutls_openpgp_crt_import
-------------------------

 -- Function: int gnutls_openpgp_crt_import (gnutls_openpgp_crt_t KEY,
          const gnutls_datum_t * DATA, gnutls_openpgp_crt_fmt_t FORMAT)
     KEY: The structure to store the parsed key.

     DATA: The RAW or BASE64 encoded key.

     FORMAT: One of gnutls_openpgp_crt_fmt_t elements.

     This function will convert the given RAW or Base64 encoded key to
     the native `gnutls_openpgp_crt_t'  format. The output will be
     stored in 'key'.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_init
-----------------------

 -- Function: int gnutls_openpgp_crt_init (gnutls_openpgp_crt_t * KEY)
     KEY: The structure to be initialized

     This function will initialize an OpenPGP key structure.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_print
------------------------

 -- Function: int gnutls_openpgp_crt_print (gnutls_openpgp_crt_t CERT,
          gnutls_certificate_print_formats_t FORMAT, gnutls_datum_t *
          OUT)
     CERT: The structure to be printed

     FORMAT: Indicate the format to use

     OUT: Newly allocated datum with (0) terminated string.

     This function will pretty print an OpenPGP certificate, suitable
     for display to a human.

     The format should be (0) for future compatibility.

     The output  `out' needs to be deallocate using `gnutls_free()' .

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_set_preferred_key_id
---------------------------------------

 -- Function: int gnutls_openpgp_crt_set_preferred_key_id
          (gnutls_openpgp_crt_t KEY, const gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the selected keyid

     This allows setting a preferred key id for the given certificate.
     This key will be used by functions that involve key handling.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_openpgp_crt_verify_ring
------------------------------

 -- Function: int gnutls_openpgp_crt_verify_ring (gnutls_openpgp_crt_t
          KEY, gnutls_openpgp_keyring_t KEYRING, unsigned int FLAGS,
          unsigned int * VERIFY)
     KEY: the structure that holds the key.

     KEYRING: holds the keyring to check against

     FLAGS: unused (should be 0)

     VERIFY: will hold the certificate verification output.

     Verify all signatures in the key, using the given set of keys
     (keyring).

     The key verification output will be put in  `verify' and will be
     one or more of the `gnutls_certificate_status_t'  enumerated
     elements bitwise or'd.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_crt_verify_self
------------------------------

 -- Function: int gnutls_openpgp_crt_verify_self (gnutls_openpgp_crt_t
          KEY, unsigned int FLAGS, unsigned int * VERIFY)
     KEY: the structure that holds the key.

     FLAGS: unused (should be 0)

     VERIFY: will hold the key verification output.

     Verifies the self signature in the key.  The key verification
     output will be put in  `verify' and will be one or more of the
     gnutls_certificate_status_t enumerated elements bitwise or'd.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_keyring_check_id
-------------------------------

 -- Function: int gnutls_openpgp_keyring_check_id
          (gnutls_openpgp_keyring_t RING, const gnutls_openpgp_keyid_t
          KEYID, unsigned int FLAGS)
     RING: holds the keyring to check against

     KEYID: will hold the keyid to check for.

     FLAGS: unused (should be 0)

     Check if a given key ID exists in the keyring.

     *Returns:* `GNUTLS_E_SUCCESS'  on success (if keyid exists) and a
     negative error code on failure.

gnutls_openpgp_keyring_deinit
-----------------------------

 -- Function: void gnutls_openpgp_keyring_deinit
          (gnutls_openpgp_keyring_t KEYRING)
     KEYRING: The structure to be initialized

     This function will deinitialize a keyring structure.

gnutls_openpgp_keyring_get_crt
------------------------------

 -- Function: int gnutls_openpgp_keyring_get_crt
          (gnutls_openpgp_keyring_t RING, unsigned int IDX,
          gnutls_openpgp_crt_t * CERT)
     RING: Holds the keyring.

     IDX: the index of the certificate to export

     CERT: An uninitialized `gnutls_openpgp_crt_t'  structure

     This function will extract an OpenPGP certificate from the given
     keyring.  If the index given is out of range
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned. The
     returned structure needs to be deinited.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_keyring_get_crt_count
------------------------------------

 -- Function: int gnutls_openpgp_keyring_get_crt_count
          (gnutls_openpgp_keyring_t RING)
     RING: is an OpenPGP key ring

     This function will return the number of OpenPGP certificates
     present in the given keyring.

     *Returns:* the number of subkeys, or a negative error code on
     error.

gnutls_openpgp_keyring_import
-----------------------------

 -- Function: int gnutls_openpgp_keyring_import
          (gnutls_openpgp_keyring_t KEYRING, const gnutls_datum_t *
          DATA, gnutls_openpgp_crt_fmt_t FORMAT)
     KEYRING: The structure to store the parsed key.

     DATA: The RAW or BASE64 encoded keyring.

     FORMAT: One of `gnutls_openpgp_keyring_fmt'  elements.

     This function will convert the given RAW or Base64 encoded keyring
     to the native `gnutls_openpgp_keyring_t'  format.  The output will
     be stored in 'keyring'.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_keyring_init
---------------------------

 -- Function: int gnutls_openpgp_keyring_init (gnutls_openpgp_keyring_t
          * KEYRING)
     KEYRING: The structure to be initialized

     This function will initialize an keyring structure.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_privkey_deinit
-----------------------------

 -- Function: void gnutls_openpgp_privkey_deinit
          (gnutls_openpgp_privkey_t KEY)
     KEY: The structure to be initialized

     This function will deinitialize a key structure.

gnutls_openpgp_privkey_export
-----------------------------

 -- Function: int gnutls_openpgp_privkey_export
          (gnutls_openpgp_privkey_t KEY, gnutls_openpgp_crt_fmt_t
          FORMAT, const char * PASSWORD, unsigned int FLAGS, void *
          OUTPUT_DATA, size_t * OUTPUT_DATA_SIZE)
     KEY: Holds the key.

     FORMAT: One of gnutls_openpgp_crt_fmt_t elements.

     PASSWORD: the password that will be used to encrypt the key.
     (unused for now)

     FLAGS: (0) for future compatibility

     OUTPUT_DATA: will contain the key base64 encoded or raw

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will convert the given key to RAW or Base64 format.
     If the buffer provided is not long enough to hold the output, then
     GNUTLS_E_SHORT_MEMORY_BUFFER will be returned.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_export_dsa_raw
-------------------------------------

 -- Function: int gnutls_openpgp_privkey_export_dsa_raw
          (gnutls_openpgp_privkey_t PKEY, gnutls_datum_t * P,
          gnutls_datum_t * Q, gnutls_datum_t * G, gnutls_datum_t * Y,
          gnutls_datum_t * X)
     PKEY: Holds the certificate

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     X: will hold the x

     This function will export the DSA private key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_export_rsa_raw
-------------------------------------

 -- Function: int gnutls_openpgp_privkey_export_rsa_raw
          (gnutls_openpgp_privkey_t PKEY, gnutls_datum_t * M,
          gnutls_datum_t * E, gnutls_datum_t * D, gnutls_datum_t * P,
          gnutls_datum_t * Q, gnutls_datum_t * U)
     PKEY: Holds the certificate

     M: will hold the modulus

     E: will hold the public exponent

     D: will hold the private exponent

     P: will hold the first prime (p)

     Q: will hold the second prime (q)

     U: will hold the coefficient

     This function will export the RSA private key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_export_subkey_dsa_raw
--------------------------------------------

 -- Function: int gnutls_openpgp_privkey_export_subkey_dsa_raw
          (gnutls_openpgp_privkey_t PKEY, unsigned int IDX,
          gnutls_datum_t * P, gnutls_datum_t * Q, gnutls_datum_t * G,
          gnutls_datum_t * Y, gnutls_datum_t * X)
     PKEY: Holds the certificate

     IDX: Is the subkey index

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     X: will hold the x

     This function will export the DSA private key's parameters found
     in the given certificate.  The new parameters will be allocated
     using `gnutls_malloc()'  and will be stored in the appropriate
     datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_export_subkey_rsa_raw
--------------------------------------------

 -- Function: int gnutls_openpgp_privkey_export_subkey_rsa_raw
          (gnutls_openpgp_privkey_t PKEY, unsigned int IDX,
          gnutls_datum_t * M, gnutls_datum_t * E, gnutls_datum_t * D,
          gnutls_datum_t * P, gnutls_datum_t * Q, gnutls_datum_t * U)
     PKEY: Holds the certificate

     IDX: Is the subkey index

     M: will hold the modulus

     E: will hold the public exponent

     D: will hold the private exponent

     P: will hold the first prime (p)

     Q: will hold the second prime (q)

     U: will hold the coefficient

     This function will export the RSA private key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_fingerprint
--------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_fingerprint
          (gnutls_openpgp_privkey_t KEY, void * FPR, size_t * FPRLEN)
     KEY: the raw data that contains the OpenPGP secret key.

     FPR: the buffer to save the fingerprint, must hold at least 20
     bytes.

     FPRLEN: the integer to save the length of the fingerprint.

     Get the fingerprint of the OpenPGP key. Depends on the algorithm,
     the fingerprint can be 16 or 20 bytes.

     *Returns:* On success, 0 is returned, or an error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_key_id
---------------------------------

 -- Function: int gnutls_openpgp_privkey_get_key_id
          (gnutls_openpgp_privkey_t KEY, gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP secret key.

     KEYID: the buffer to save the keyid.

     Get key-id.

     *Returns:* the 64-bit keyID of the OpenPGP key.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_pk_algorithm
---------------------------------------

 -- Function: gnutls_pk_algorithm_t
gnutls_openpgp_privkey_get_pk_algorithm (gnutls_openpgp_privkey_t KEY,
          unsigned int * BITS)
     KEY: is an OpenPGP key

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of an OpenPGP
     certificate.

     If bits is non null, it should have enough size to hold the
     parameters size in bits. For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_preferred_key_id
-------------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_preferred_key_id
          (gnutls_openpgp_privkey_t KEY, gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the struct to save the keyid.

     Get the preferred key-id for the key.

     *Returns:* the 64-bit preferred keyID of the OpenPGP key, or if it
     hasn't been set it returns `GNUTLS_E_INVALID_REQUEST' .

gnutls_openpgp_privkey_get_revoked_status
-----------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_revoked_status
          (gnutls_openpgp_privkey_t KEY)
     KEY: the structure that contains the OpenPGP private key.

     Get revocation status of key.

     *Returns:* true (1) if the key has been revoked, or false (0) if it
     has not, or a negative error code indicates an error.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_count
---------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_subkey_count
          (gnutls_openpgp_privkey_t KEY)
     KEY: is an OpenPGP key

     This function will return the number of subkeys present in the
     given OpenPGP certificate.

     *Returns:* the number of subkeys, or a negative error code on
     error.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_creation_time
-----------------------------------------------

 -- Function: time_t gnutls_openpgp_privkey_get_subkey_creation_time
          (gnutls_openpgp_privkey_t KEY, unsigned int IDX)
     KEY: the structure that contains the OpenPGP private key.

     IDX: the subkey index

     Get subkey creation time.

     *Returns:* the timestamp when the OpenPGP key was created.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_fingerprint
---------------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_subkey_fingerprint
          (gnutls_openpgp_privkey_t KEY, unsigned int IDX, void * FPR,
          size_t * FPRLEN)
     KEY: the raw data that contains the OpenPGP secret key.

     IDX: the subkey index

     FPR: the buffer to save the fingerprint, must hold at least 20
     bytes.

     FPRLEN: the integer to save the length of the fingerprint.

     Get the fingerprint of an OpenPGP subkey.  Depends on the
     algorithm, the fingerprint can be 16 or 20 bytes.

     *Returns:* On success, 0 is returned, or an error code.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_id
------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_subkey_id
          (gnutls_openpgp_privkey_t KEY, unsigned int IDX,
          gnutls_openpgp_keyid_t KEYID)
     KEY: the structure that contains the OpenPGP secret key.

     IDX: the subkey index

     KEYID: the buffer to save the keyid.

     Get the key-id for the subkey.

     *Returns:* the 64-bit keyID of the OpenPGP key.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_idx
-------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_subkey_idx
          (gnutls_openpgp_privkey_t KEY, const gnutls_openpgp_keyid_t
          KEYID)
     KEY: the structure that contains the OpenPGP private key.

     KEYID: the keyid.

     Get index of subkey.

     *Returns:* the index of the subkey or a negative error value.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_pk_algorithm
----------------------------------------------

 -- Function: gnutls_pk_algorithm_t
gnutls_openpgp_privkey_get_subkey_pk_algorithm
          (gnutls_openpgp_privkey_t KEY, unsigned int IDX, unsigned int
          * BITS)
     KEY: is an OpenPGP key

     IDX: is the subkey index

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of a subkey of
     an OpenPGP certificate.

     If bits is non null, it should have enough size to hold the
     parameters size in bits. For RSA the bits returned is the modulus.
     For DSA the bits returned are of the public exponent.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

     *Since:* 2.4.0

gnutls_openpgp_privkey_get_subkey_revoked_status
------------------------------------------------

 -- Function: int gnutls_openpgp_privkey_get_subkey_revoked_status
          (gnutls_openpgp_privkey_t KEY, unsigned int IDX)
     KEY: the structure that contains the OpenPGP private key.

     IDX: is the subkey index

     Get revocation status of key.

     *Returns:* true (1) if the key has been revoked, or false (0) if it
     has not, or a negative error code indicates an error.

     *Since:* 2.4.0

gnutls_openpgp_privkey_import
-----------------------------

 -- Function: int gnutls_openpgp_privkey_import
          (gnutls_openpgp_privkey_t KEY, const gnutls_datum_t * DATA,
          gnutls_openpgp_crt_fmt_t FORMAT, const char * PASSWORD,
          unsigned int FLAGS)
     KEY: The structure to store the parsed key.

     DATA: The RAW or BASE64 encoded key.

     FORMAT: One of `gnutls_openpgp_crt_fmt_t'  elements.

     PASSWORD: not used for now

     FLAGS: should be (0)

     This function will convert the given RAW or Base64 encoded key to
     the native gnutls_openpgp_privkey_t format.  The output will be
     stored in 'key'.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_privkey_init
---------------------------

 -- Function: int gnutls_openpgp_privkey_init (gnutls_openpgp_privkey_t
          * KEY)
     KEY: The structure to be initialized

     This function will initialize an OpenPGP key structure.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an error code.

gnutls_openpgp_privkey_sec_param
--------------------------------

 -- Function: gnutls_sec_param_t gnutls_openpgp_privkey_sec_param
          (gnutls_openpgp_privkey_t KEY)
     KEY: a key structure

     This function will return the security parameter appropriate with
     this private key.

     *Returns:* On success, a valid security parameter is returned
     otherwise `GNUTLS_SEC_PARAM_UNKNOWN'  is returned.

     *Since:* 2.12.0

gnutls_openpgp_privkey_set_preferred_key_id
-------------------------------------------

 -- Function: int gnutls_openpgp_privkey_set_preferred_key_id
          (gnutls_openpgp_privkey_t KEY, const gnutls_openpgp_keyid_t
          KEYID)
     KEY: the structure that contains the OpenPGP public key.

     KEYID: the selected keyid

     This allows setting a preferred key id for the given certificate.
     This key will be used by functions that involve key handling.

     *Returns:* On success, 0 is returned, or an error code.

gnutls_openpgp_set_recv_key_function
------------------------------------

 -- Function: void gnutls_openpgp_set_recv_key_function
          (gnutls_session_t SESSION, gnutls_openpgp_recv_key_func FUNC)
     SESSION: a TLS session

     FUNC: the callback

     This funtion will set a key retrieval function for OpenPGP keys.
     This callback is only useful in server side, and will be used if
     the peer sent a key fingerprint instead of a full key.


File: gnutls.info,  Node: PKCS 12 API,  Next: PKCS 11 API,  Prev: OpenPGP API,  Up: API reference

E.6 PKCS 12 API
===============

The following functions are to be used for PKCS 12 handling.  Their
prototypes lie in `gnutls/pkcs12.h'.

gnutls_pkcs12_bag_decrypt
-------------------------

 -- Function: int gnutls_pkcs12_bag_decrypt (gnutls_pkcs12_bag_t BAG,
          const char * PASS)
     BAG: The bag

     PASS: The password used for encryption, must be ASCII.

     This function will decrypt the given encrypted bag and return 0 on
     success.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_pkcs12_bag_deinit
------------------------

 -- Function: void gnutls_pkcs12_bag_deinit (gnutls_pkcs12_bag_t BAG)
     BAG: The structure to be initialized

     This function will deinitialize a PKCS12 Bag structure.

gnutls_pkcs12_bag_encrypt
-------------------------

 -- Function: int gnutls_pkcs12_bag_encrypt (gnutls_pkcs12_bag_t BAG,
          const char * PASS, unsigned int FLAGS)
     BAG: The bag

     PASS: The password used for encryption, must be ASCII

     FLAGS: should be one of `gnutls_pkcs_encrypt_flags_t'  elements
     bitwise or'd

     This function will encrypt the given bag.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error code is returned.

gnutls_pkcs12_bag_get_count
---------------------------

 -- Function: int gnutls_pkcs12_bag_get_count (gnutls_pkcs12_bag_t BAG)
     BAG: The bag

     This function will return the number of the elements withing the
     bag.

     *Returns:* Number of elements in bag, or an negative error code on
     error.

gnutls_pkcs12_bag_get_data
--------------------------

 -- Function: int gnutls_pkcs12_bag_get_data (gnutls_pkcs12_bag_t BAG,
          int INDX, gnutls_datum_t * DATA)
     BAG: The bag

     INDX: The element of the bag to get the data from

     DATA: where the bag's data will be. Should be treated as constant.

     This function will return the bag's data. The data is a constant
     that is stored into the bag.  Should not be accessed after the bag
     is deleted.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_bag_get_friendly_name
-----------------------------------

 -- Function: int gnutls_pkcs12_bag_get_friendly_name
          (gnutls_pkcs12_bag_t BAG, int INDX, char ** NAME)
     BAG: The bag

     INDX: The bag's element to add the id

     NAME: will hold a pointer to the name (to be treated as const)

     This function will return the friendly name, of the specified bag
     element.  The key ID is usually used to distinguish the local
     private key and the certificate pair.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. or a negative error code on
     error.

gnutls_pkcs12_bag_get_key_id
----------------------------

 -- Function: int gnutls_pkcs12_bag_get_key_id (gnutls_pkcs12_bag_t
          BAG, int INDX, gnutls_datum_t * ID)
     BAG: The bag

     INDX: The bag's element to add the id

     ID: where the ID will be copied (to be treated as const)

     This function will return the key ID, of the specified bag element.
     The key ID is usually used to distinguish the local private key and
     the certificate pair.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. or a negative error code on
     error.

gnutls_pkcs12_bag_get_type
--------------------------

 -- Function: gnutls_pkcs12_bag_type_t gnutls_pkcs12_bag_get_type
          (gnutls_pkcs12_bag_t BAG, int INDX)
     BAG: The bag

     INDX: The element of the bag to get the type

     This function will return the bag's type.

     *Returns:* One of the `gnutls_pkcs12_bag_type_t'  enumerations.

gnutls_pkcs12_bag_init
----------------------

 -- Function: int gnutls_pkcs12_bag_init (gnutls_pkcs12_bag_t * BAG)
     BAG: The structure to be initialized

     This function will initialize a PKCS12 bag structure. PKCS12 Bags
     usually contain private keys, lists of X.509 Certificates and X.509
     Certificate revocation lists.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_bag_set_crl
-------------------------

 -- Function: int gnutls_pkcs12_bag_set_crl (gnutls_pkcs12_bag_t BAG,
          gnutls_x509_crl_t CRL)
     BAG: The bag

     CRL: the CRL to be copied.

     This function will insert the given CRL into the bag. This is just
     a wrapper over `gnutls_pkcs12_bag_set_data()' .

     *Returns:* the index of the added bag on success, or a negative
     error code on failure.

gnutls_pkcs12_bag_set_crt
-------------------------

 -- Function: int gnutls_pkcs12_bag_set_crt (gnutls_pkcs12_bag_t BAG,
          gnutls_x509_crt_t CRT)
     BAG: The bag

     CRT: the certificate to be copied.

     This function will insert the given certificate into the bag. This
     is just a wrapper over `gnutls_pkcs12_bag_set_data()' .

     *Returns:* the index of the added bag on success, or a negative
     value on failure.

gnutls_pkcs12_bag_set_data
--------------------------

 -- Function: int gnutls_pkcs12_bag_set_data (gnutls_pkcs12_bag_t BAG,
          gnutls_pkcs12_bag_type_t TYPE, const gnutls_datum_t * DATA)
     BAG: The bag

     TYPE: The data's type

     DATA: the data to be copied.

     This function will insert the given data of the given type into
     the bag.

     *Returns:* the index of the added bag on success, or a negative
     value on error.

gnutls_pkcs12_bag_set_friendly_name
-----------------------------------

 -- Function: int gnutls_pkcs12_bag_set_friendly_name
          (gnutls_pkcs12_bag_t BAG, int INDX, const char * NAME)
     BAG: The bag

     INDX: The bag's element to add the id

     NAME: the name

     This function will add the given key friendly name, to the
     specified, by the index, bag element. The name will be encoded as
     a 'Friendly name' bag attribute, which is usually used to set a
     user name to the local private key and the certificate pair.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. or a negative error code on
     error.

gnutls_pkcs12_bag_set_key_id
----------------------------

 -- Function: int gnutls_pkcs12_bag_set_key_id (gnutls_pkcs12_bag_t
          BAG, int INDX, const gnutls_datum_t * ID)
     BAG: The bag

     INDX: The bag's element to add the id

     ID: the ID

     This function will add the given key ID, to the specified, by the
     index, bag element. The key ID will be encoded as a 'Local key
     identifier' bag attribute, which is usually used to distinguish
     the local private key and the certificate pair.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value. or a negative error code on
     error.

gnutls_pkcs12_deinit
--------------------

 -- Function: void gnutls_pkcs12_deinit (gnutls_pkcs12_t PKCS12)
     PKCS12: The structure to be initialized

     This function will deinitialize a PKCS12 structure.

gnutls_pkcs12_export
--------------------

 -- Function: int gnutls_pkcs12_export (gnutls_pkcs12_t PKCS12,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     PKCS12: Holds the pkcs12 structure

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a structure PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the pkcs12 structure to DER or PEM
     format.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size will be updated and GNUTLS_E_SHORT_MEMORY_BUFFER
     will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     PKCS12".

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

gnutls_pkcs12_generate_mac
--------------------------

 -- Function: int gnutls_pkcs12_generate_mac (gnutls_pkcs12_t PKCS12,
          const char * PASS)
     PKCS12: should contain a gnutls_pkcs12_t structure

     PASS: The password for the MAC

     This function will generate a MAC for the PKCS12 structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_get_bag
---------------------

 -- Function: int gnutls_pkcs12_get_bag (gnutls_pkcs12_t PKCS12, int
          INDX, gnutls_pkcs12_bag_t BAG)
     PKCS12: should contain a gnutls_pkcs12_t structure

     INDX: contains the index of the bag to extract

     BAG: An initialized bag, where the contents of the bag will be
     copied

     This function will return a Bag from the PKCS12 structure.

     After the last Bag has been read
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  will be returned.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_import
--------------------

 -- Function: int gnutls_pkcs12_import (gnutls_pkcs12_t PKCS12, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT, unsigned
          int FLAGS)
     PKCS12: The structure to store the parsed PKCS12.

     DATA: The DER or PEM encoded PKCS12.

     FORMAT: One of DER or PEM

     FLAGS: an ORed sequence of gnutls_privkey_pkcs8_flags

     This function will convert the given DER or PEM encoded PKCS12 to
     the native gnutls_pkcs12_t format. The output will be stored in
     'pkcs12'.

     If the PKCS12 is PEM encoded it should have a header of "PKCS12".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_init
------------------

 -- Function: int gnutls_pkcs12_init (gnutls_pkcs12_t * PKCS12)
     PKCS12: The structure to be initialized

     This function will initialize a PKCS12 structure. PKCS12 structures
     usually contain lists of X.509 Certificates and X.509 Certificate
     revocation lists.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_set_bag
---------------------

 -- Function: int gnutls_pkcs12_set_bag (gnutls_pkcs12_t PKCS12,
          gnutls_pkcs12_bag_t BAG)
     PKCS12: should contain a gnutls_pkcs12_t structure

     BAG: An initialized bag

     This function will insert a Bag into the PKCS12 structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs12_verify_mac
------------------------

 -- Function: int gnutls_pkcs12_verify_mac (gnutls_pkcs12_t PKCS12,
          const char * PASS)
     PKCS12: should contain a gnutls_pkcs12_t structure

     PASS: The password for the MAC

     This function will verify the MAC for the PKCS12 structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.


File: gnutls.info,  Node: PKCS 11 API,  Next: Abstract key API,  Prev: PKCS 12 API,  Up: API reference

E.7 Hardware token via PKCS 11 API
==================================

The following functions are to be used for PKCS 11 handling.  Their
prototypes lie in `gnutls/pkcs11.h'.

gnutls_pkcs11_add_provider
--------------------------

 -- Function: int gnutls_pkcs11_add_provider (const char * NAME, const
          char * PARAMS)
     NAME: The filename of the module

     PARAMS: should be NULL

     This function will load and add a PKCS 11 module to the module
     list used in gnutls. After this function is called the module will
     be used for PKCS 11 operations.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_copy_secret_key
-----------------------------

 -- Function: int gnutls_pkcs11_copy_secret_key (const char *
          TOKEN_URL, gnutls_datum_t * KEY, const char * LABEL, unsigned
          int KEY_USAGE, unsigned int FLAGS)
     TOKEN_URL: A PKCS `11'  URL specifying a token

     KEY: The raw key

     LABEL: A name to be used for the stored data

     KEY_USAGE: One of GNUTLS_KEY_*

     FLAGS: One of GNUTLS_PKCS11_OBJ_FLAG_*

     This function will copy a raw secret (symmetric) key into a PKCS
     `11' token specified by a URL. The key can be marked as sensitive
     or not.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_copy_x509_crt
---------------------------

 -- Function: int gnutls_pkcs11_copy_x509_crt (const char * TOKEN_URL,
          gnutls_x509_crt_t CRT, const char * LABEL, unsigned int FLAGS)
     TOKEN_URL: A PKCS `11'  URL specifying a token

     CRT: A certificate

     LABEL: A name to be used for the stored data

     FLAGS: One of GNUTLS_PKCS11_OBJ_FLAG_*

     This function will copy a certificate into a PKCS `11'  token
     specified by a URL. The certificate can be marked as trusted or
     not.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_copy_x509_privkey
-------------------------------

 -- Function: int gnutls_pkcs11_copy_x509_privkey (const char *
          TOKEN_URL, gnutls_x509_privkey_t KEY, const char * LABEL,
          unsigned int KEY_USAGE, unsigned int FLAGS)
     TOKEN_URL: A PKCS `11'  URL specifying a token

     KEY: A private key

     LABEL: A name to be used for the stored data

     KEY_USAGE: One of GNUTLS_KEY_*

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will copy a private key into a PKCS `11'  token
     specified by a URL. It is highly recommended flags to contain
     `GNUTLS_PKCS11_OBJ_FLAG_MARK_SENSITIVE' unless there is a strong
     reason not to.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_deinit
--------------------

 -- Function: void gnutls_pkcs11_deinit ( VOID)
     This function will deinitialize the PKCS 11 subsystem in gnutls.

     *Since:* 2.12.0

gnutls_pkcs11_delete_url
------------------------

 -- Function: int gnutls_pkcs11_delete_url (const char * OBJECT_URL,
          unsigned int FLAGS)
     OBJECT_URL: The URL of the object to delete.

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will delete objects matching the given URL.  Note
     that not all tokens support the delete operation.

     *Returns:* On success, the number of objects deleted is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_init
------------------

 -- Function: int gnutls_pkcs11_init (unsigned int FLAGS, const char *
          DEPRECATED_CONFIG_FILE)
     FLAGS: `GNUTLS_PKCS11_FLAG_MANUAL'  or `GNUTLS_PKCS11_FLAG_AUTO'

     DEPRECATED_CONFIG_FILE: either NULL or the location of a deprecated
     configuration file

     This function will initialize the PKCS 11 subsystem in gnutls. It
     will read configuration files if `GNUTLS_PKCS11_FLAG_AUTO'  is
     used or allow you to independently load PKCS 11 modules using
     `gnutls_pkcs11_add_provider()' if `GNUTLS_PKCS11_FLAG_MANUAL'  is
     specified.

     Normally you don't need to call this function since it is being
     called by `gnutls_global_init()'  using the
     `GNUTLS_PKCS11_FLAG_AUTO' . If other option is required then it
     must be called before it.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_obj_deinit
------------------------

 -- Function: void gnutls_pkcs11_obj_deinit (gnutls_pkcs11_obj_t OBJ)
     OBJ: The structure to be initialized

     This function will deinitialize a certificate structure.

     *Since:* 2.12.0

gnutls_pkcs11_obj_export
------------------------

 -- Function: int gnutls_pkcs11_obj_export (gnutls_pkcs11_obj_t OBJ,
          void * OUTPUT_DATA, size_t * OUTPUT_DATA_SIZE)
     OBJ: Holds the object

     OUTPUT_DATA: will contain a certificate PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the PKCS11 object data.  It is normal for
     data to be inaccesible and in that case `GNUTLS_E_INVALID_REQUEST'
     will be returned.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and GNUTLS_E_SHORT_MEMORY_BUFFER will
     be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     CERTIFICATE".

     *Returns:* In case of failure a negative error code will be
     returned, and `GNUTLS_E_SUCCESS'  (0) on success.

     *Since:* 2.12.0

gnutls_pkcs11_obj_export_url
----------------------------

 -- Function: int gnutls_pkcs11_obj_export_url (gnutls_pkcs11_obj_t
          OBJ, gnutls_pkcs11_url_type_t DETAILED, char ** URL)
     OBJ: Holds the PKCS 11 certificate

     DETAILED: non zero if a detailed URL is required

     URL: will contain an allocated url

     This function will export a URL identifying the given certificate.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_obj_get_info
--------------------------

 -- Function: int gnutls_pkcs11_obj_get_info (gnutls_pkcs11_obj_t CRT,
          gnutls_pkcs11_obj_info_t ITYPE, void * OUTPUT, size_t *
          OUTPUT_SIZE)
     CRT: should contain a `gnutls_pkcs11_obj_t'  structure

     ITYPE: Denotes the type of information requested

     OUTPUT: where output will be stored

     OUTPUT_SIZE: contains the maximum size of the output and will be
     overwritten with actual

     This function will return information about the PKCS11 certificate
     such as the label, id as well as token information where the key is
     stored. When output is text it returns null terminated string
     although  `output_size' contains the size of the actual data only.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success or a negative error
     code on error.

     *Since:* 2.12.0

gnutls_pkcs11_obj_get_type
--------------------------

 -- Function: gnutls_pkcs11_obj_type_t gnutls_pkcs11_obj_get_type
          (gnutls_pkcs11_obj_t OBJ)
     OBJ: Holds the PKCS 11 object

     This function will return the type of the certificate being stored
     in the structure.

     *Returns:* The type of the certificate.

     *Since:* 2.12.0

gnutls_pkcs11_obj_import_url
----------------------------

 -- Function: int gnutls_pkcs11_obj_import_url (gnutls_pkcs11_obj_t
          CERT, const char * URL, unsigned int FLAGS)
     CERT: The structure to store the parsed certificate

     URL: a PKCS 11 url identifying the key

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will "import" a PKCS 11 URL identifying a certificate
     key to the `gnutls_pkcs11_obj_t'  structure. This does not involve
     any parsing (such as X.509 or OpenPGP) since the
     `gnutls_pkcs11_obj_t'  is format agnostic. Only data are
     transferred.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_obj_init
----------------------

 -- Function: int gnutls_pkcs11_obj_init (gnutls_pkcs11_obj_t * OBJ)
     OBJ: The structure to be initialized

     This function will initialize a pkcs11 certificate structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_obj_list_import_url
---------------------------------

 -- Function: int gnutls_pkcs11_obj_list_import_url
          (gnutls_pkcs11_obj_t * P_LIST, unsigned int * N_LIST, const
          char * URL, gnutls_pkcs11_obj_attr_t ATTRS, unsigned int
          FLAGS)
     P_LIST: An uninitialized object list (may be NULL)

     N_LIST: initially should hold the maximum size of the list. Will
     contain the actual size.

     URL: A PKCS 11 url identifying a set of objects

     ATTRS: Attributes of type `gnutls_pkcs11_obj_attr_t'  that can be
     used to limit output

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will initialize and set values to an object list by
     using all objects identified by a PKCS 11 URL.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_obj_list_import_url2
----------------------------------

 -- Function: int gnutls_pkcs11_obj_list_import_url2
          (gnutls_pkcs11_obj_t ** P_LIST, unsigned int * N_LIST, const
          char * URL, gnutls_pkcs11_obj_attr_t ATTRS, unsigned int
          FLAGS)
     P_LIST: An uninitialized object list (may be NULL)

     N_LIST: It will contain the size of the list.

     URL: A PKCS 11 url identifying a set of objects

     ATTRS: Attributes of type `gnutls_pkcs11_obj_attr_t'  that can be
     used to limit output

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will initialize and set values to an object list by
     using all objects identified by the PKCS 11 URL. The output is
     stored in  `p_list' , which will be initialized.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.1

gnutls_pkcs11_privkey_deinit
----------------------------

 -- Function: void gnutls_pkcs11_privkey_deinit
          (gnutls_pkcs11_privkey_t KEY)
     KEY: The structure to be initialized

     This function will deinitialize a private key structure.

gnutls_pkcs11_privkey_export_url
--------------------------------

 -- Function: int gnutls_pkcs11_privkey_export_url
          (gnutls_pkcs11_privkey_t KEY, gnutls_pkcs11_url_type_t
          DETAILED, char ** URL)
     KEY: Holds the PKCS 11 key

     DETAILED: non zero if a detailed URL is required

     URL: will contain an allocated url

     This function will export a URL identifying the given key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs11_privkey_generate
------------------------------

 -- Function: int gnutls_pkcs11_privkey_generate (const char* URL,
          gnutls_pk_algorithm_t PK, unsigned int BITS, const char*
          LABEL, unsigned int FLAGS)
     URL: a token URL

     PK: the public key algorithm

     BITS: the security bits

     LABEL: a label

     FLAGS: should be zero

     This function will generate a private key in the specified by the
     `url' token. The pivate key will be generate within the token and
     will not be exportable.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pkcs11_privkey_get_info
------------------------------

 -- Function: int gnutls_pkcs11_privkey_get_info
          (gnutls_pkcs11_privkey_t PKEY, gnutls_pkcs11_obj_info_t
          ITYPE, void * OUTPUT, size_t * OUTPUT_SIZE)
     PKEY: should contain a `gnutls_pkcs11_privkey_t'  structure

     ITYPE: Denotes the type of information requested

     OUTPUT: where output will be stored

     OUTPUT_SIZE: contains the maximum size of the output and will be
     overwritten with actual

     This function will return information about the PKCS 11 private
     key such as the label, id as well as token information where the
     key is stored. When output is text it returns null terminated
     string although `output_size'  contains the size of the actual
     data only.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success or a negative error
     code on error.

gnutls_pkcs11_privkey_get_pk_algorithm
--------------------------------------

 -- Function: int gnutls_pkcs11_privkey_get_pk_algorithm
          (gnutls_pkcs11_privkey_t KEY, unsigned int * BITS)
     KEY: should contain a `gnutls_pkcs11_privkey_t'  structure

     BITS: if bits is non null it will hold the size of the parameters'
     in bits

     This function will return the public key algorithm of a private
     key.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

gnutls_pkcs11_privkey_import_url
--------------------------------

 -- Function: int gnutls_pkcs11_privkey_import_url
          (gnutls_pkcs11_privkey_t PKEY, const char * URL, unsigned int
          FLAGS)
     PKEY: The structure to store the parsed key

     URL: a PKCS 11 url identifying the key

     FLAGS: sequence of GNUTLS_PKCS_PRIVKEY_*

     This function will "import" a PKCS 11 URL identifying a private
     key to the `gnutls_pkcs11_privkey_t'  structure. In reality since
     in most cases keys cannot be exported, the private key structure
     is being associated with the available operations on the token.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs11_privkey_init
--------------------------

 -- Function: int gnutls_pkcs11_privkey_init (gnutls_pkcs11_privkey_t *
          KEY)
     KEY: The structure to be initialized

     This function will initialize an private key structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs11_reinit
--------------------

 -- Function: int gnutls_pkcs11_reinit ( VOID)
     This function will reinitialize the PKCS 11 subsystem in gnutls.
     This is required by PKCS 11 when an application uses `fork()' . The
     reinitialization function must be called on the child.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pkcs11_set_pin_function
------------------------------

 -- Function: void gnutls_pkcs11_set_pin_function
          (gnutls_pkcs11_pin_callback_t FN, void * USERDATA)
     FN: The PIN callback, a `gnutls_pkcs11_pin_callback_t()'  function.

     USERDATA: data to be supplied to callback

     This function will set a callback function to be used when a PIN is
     required for PKCS 11 operations.  See
     `gnutls_pkcs11_pin_callback_t()'  on how the callback should
     behave.

     *Since:* 2.12.0

gnutls_pkcs11_set_token_function
--------------------------------

 -- Function: void gnutls_pkcs11_set_token_function
          (gnutls_pkcs11_token_callback_t FN, void * USERDATA)
     FN: The token callback

     USERDATA: data to be supplied to callback

     This function will set a callback function to be used when a token
     needs to be inserted to continue PKCS 11 operations.

     *Since:* 2.12.0

gnutls_pkcs11_token_get_flags
-----------------------------

 -- Function: int gnutls_pkcs11_token_get_flags (const char * URL,
          unsigned int * FLAGS)
     URL: should contain a PKCS 11 URL

     FLAGS: The output flags (GNUTLS_PKCS11_TOKEN_*)

     This function will return information about the PKCS 11 token
     flags.  The flags from the `gnutls_pkcs11_token_info_t'
     enumeration.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success or a negative error
     code on error.

     *Since:* 2.12.0

gnutls_pkcs11_token_get_info
----------------------------

 -- Function: int gnutls_pkcs11_token_get_info (const char * URL,
          gnutls_pkcs11_token_info_t TTYPE, void * OUTPUT, size_t *
          OUTPUT_SIZE)
     URL: should contain a PKCS 11 URL

     TTYPE: Denotes the type of information requested

     OUTPUT: where output will be stored

     OUTPUT_SIZE: contains the maximum size of the output and will be
     overwritten with actual

     This function will return information about the PKCS 11 token such
     as the label, id, etc.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success or a negative error
     code on error.

     *Since:* 2.12.0

gnutls_pkcs11_token_get_mechanism
---------------------------------

 -- Function: int gnutls_pkcs11_token_get_mechanism (const char * URL,
          unsigned int IDX, unsigned long * MECHANISM)
     URL: should contain a PKCS 11 URL

     IDX: The index of the mechanism

     MECHANISM: The PKCS `11'  mechanism ID

     This function will return the names of the supported mechanisms by
     the token. It should be called with an increasing index until it
     return GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success or a negative error
     code on error.

     *Since:* 2.12.0

gnutls_pkcs11_token_get_url
---------------------------

 -- Function: int gnutls_pkcs11_token_get_url (unsigned int SEQ,
          gnutls_pkcs11_url_type_t DETAILED, char ** URL)
     SEQ: sequence number starting from 0

     DETAILED: non zero if a detailed URL is required

     URL: will contain an allocated url

     This function will return the URL for each token available in
     system. The url has to be released using `gnutls_free()'

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE'  if the sequence number
     exceeds the available tokens, otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pkcs11_token_init
------------------------

 -- Function: int gnutls_pkcs11_token_init (const char * TOKEN_URL,
          const char * SO_PIN, const char * LABEL)
     TOKEN_URL: A PKCS `11'  URL specifying a token

     SO_PIN: Security Officer's PIN

     LABEL: A name to be used for the token

     This function will initialize (format) a token. If the token is at
     a factory defaults state the security officer's PIN given will be
     set to be the default. Otherwise it should match the officer's PIN.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs11_token_set_pin
---------------------------

 -- Function: int gnutls_pkcs11_token_set_pin (const char * TOKEN_URL,
          const char * OLDPIN, const char * NEWPIN, unsigned int FLAGS)
     TOKEN_URL: A PKCS `11'  URL specifying a token

     OLDPIN: old user's PIN

     NEWPIN: new user's PIN

     FLAGS: one of `gnutls_pkcs11_pin_flag_t' .

     This function will modify or set a user's PIN for the given token.
     If it is called to set a user pin for first time the oldpin must
     be NULL.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_pkcs11_type_get_name
---------------------------

 -- Function: const char * gnutls_pkcs11_type_get_name
          (gnutls_pkcs11_obj_type_t TYPE)
     TYPE: Holds the PKCS 11 object type, a `gnutls_pkcs11_obj_type_t' .

     This function will return a human readable description of the
     PKCS11 object type  `obj' .  It will return "Unknown" for unknown
     types.

     *Returns:* human readable string labeling the PKCS11 object type
     `type' .

     *Since:* 2.12.0

gnutls_x509_crt_import_pkcs11
-----------------------------

 -- Function: int gnutls_x509_crt_import_pkcs11 (gnutls_x509_crt_t CRT,
          gnutls_pkcs11_obj_t PKCS11_CRT)
     CRT: A certificate of type `gnutls_x509_crt_t'

     PKCS11_CRT: A PKCS 11 object that contains a certificate

     This function will import a PKCS 11 certificate to a
     `gnutls_x509_crt_t' structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_x509_crt_import_pkcs11_url
---------------------------------

 -- Function: int gnutls_x509_crt_import_pkcs11_url (gnutls_x509_crt_t
          CRT, const char * URL, unsigned int FLAGS)
     CRT: A certificate of type `gnutls_x509_crt_t'

     URL: A PKCS 11 url

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will import a PKCS 11 certificate directly from a
     token without involving the `gnutls_pkcs11_obj_t'  structure. This
     function will fail if the certificate stored is not of X.509 type.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_x509_crt_list_import_pkcs11
----------------------------------

 -- Function: int gnutls_x509_crt_list_import_pkcs11 (gnutls_x509_crt_t
          * CERTS, unsigned int CERT_MAX, gnutls_pkcs11_obj_t * const
          OBJS, unsigned int FLAGS)
     CERTS: A list of certificates of type `gnutls_x509_crt_t'

     CERT_MAX: The maximum size of the list

     OBJS: A list of PKCS 11 objects

     FLAGS: 0 for now

     This function will import a PKCS 11 certificate list to a list of
     `gnutls_x509_crt_t'  structure. These must not be initialized.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0


File: gnutls.info,  Node: Abstract key API,  Next: Cryptographic API,  Prev: PKCS 11 API,  Up: API reference

E.8 Abstract key API
====================

The following functions are to be used for abstract key handling.
Their prototypes lie in `gnutls/abstract.h'.

gnutls_certificate_set_key
--------------------------

 -- Function: int gnutls_certificate_set_key
          (gnutls_certificate_credentials_t RES, const char** NAMES,
          int NAMES_SIZE, gnutls_pcert_st * PCERT_LIST, int
          PCERT_LIST_SIZE, gnutls_privkey_t KEY)
     RES: is a `gnutls_certificate_credentials_t'  structure.

     NAMES: is an array of DNS name of the certificate (NULL if none)

     NAMES_SIZE: holds the size of the names list

     PCERT_LIST: contains a certificate list (path) for the specified
     private key

     PCERT_LIST_SIZE: holds the size of the certificate list

     KEY: is a gnutls_x509_privkey_t key

     This function sets a certificate/private key pair in the
     gnutls_certificate_credentials_t structure.  This function may be
     called more than once, in case multiple keys/certificates exist for
     the server.  For clients that wants to send more than its own end
     entity certificate (e.g., also an intermediate CA cert) then put
     the certificate chain in  `pcert_list' . The  `pcert_list' and
     `key' will become part of the credentials structure and must not
     be deallocated. They will be automatically deallocated when  `res'
     is deinitialized.

     *Returns:* `GNUTLS_E_SUCCESS'  (0) on success, or a negative error
     code.

     *Since:* 3.0

gnutls_certificate_set_retrieve_function2
-----------------------------------------

 -- Function: void gnutls_certificate_set_retrieve_function2
          (gnutls_certificate_credentials_t CRED,
          gnutls_certificate_retrieve_function2 * FUNC)
     CRED: is a `gnutls_certificate_credentials_t'  structure.

     FUNC: is the callback function

     This function sets a callback to be called in order to retrieve the
     certificate to be used in the handshake.

     The callback's function prototype is: int
     (*callback)(gnutls_session_t, const gnutls_datum_t* req_ca_dn, int
     nreqs, const gnutls_pk_algorithm_t* pk_algos, int pk_algos_length,
     gnutls_pcert_st** pcert, unsigned int *pcert_length,
     gnutls_privkey_t * pkey);

     `req_ca_cert' is only used in X.509 certificates.  Contains a list
     with the CA names that the server considers trusted.  Normally we
     should send a certificate that is signed by one of these CAs.
     These names are DER encoded. To get a more meaningful value use
     the function `gnutls_x509_rdn_get()' .

     `pk_algos' contains a list with server's acceptable signature
     algorithms.  The certificate returned should support the server's
     given algorithms.

     `pcert' should contain a single certificate and public or a list
     of them.

     `pcert_length' is the size of the previous list.

     `pkey' is the private key.

     If the callback function is provided then gnutls will call it, in
     the handshake, after the certificate request message has been
     received.

     In server side pk_algos and req_ca_dn are NULL.

     The callback function should set the certificate list to be sent,
     and return 0 on success. If no certificate was selected then the
     number of certificates should be set to zero. The value (-1)
     indicates error and the handshake will be terminated.

     *Since:* 3.0

gnutls_pcert_deinit
-------------------

 -- Function: void gnutls_pcert_deinit (gnutls_pcert_st * PCERT)
     PCERT: The structure to be deinitialized

     This function will deinitialize a pcert structure.

     *Since:* 3.0

gnutls_pcert_import_openpgp
---------------------------

 -- Function: int gnutls_pcert_import_openpgp (gnutls_pcert_st* PCERT,
          gnutls_openpgp_crt_t CRT, unsigned int FLAGS)
     PCERT: The pcert structure

     CRT: The raw certificate to be imported

     FLAGS: zero for now

     This convenience function will import the given certificate to a
     `gnutls_pcert_st'  structure. The structure must be deinitialized
     afterwards using `gnutls_pcert_deinit()' ;

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pcert_import_openpgp_raw
-------------------------------

 -- Function: int gnutls_pcert_import_openpgp_raw (gnutls_pcert_st *
          PCERT, const gnutls_datum_t* CERT, gnutls_openpgp_crt_fmt_t
          FORMAT, gnutls_openpgp_keyid_t KEYID, unsigned int FLAGS)
     PCERT: The pcert structure

     CERT: The raw certificate to be imported

     FORMAT: The format of the certificate

     KEYID: The key ID to use (NULL for the master key)

     FLAGS: zero for now

     This convenience function will import the given certificate to a
     `gnutls_pcert_st'  structure. The structure must be deinitialized
     afterwards using `gnutls_pcert_deinit()' ;

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pcert_import_x509
------------------------

 -- Function: int gnutls_pcert_import_x509 (gnutls_pcert_st* PCERT,
          gnutls_x509_crt_t CRT, unsigned int FLAGS)
     PCERT: The pcert structure

     CRT: The raw certificate to be imported

     FLAGS: zero for now

     This convenience function will import the given certificate to a
     `gnutls_pcert_st'  structure. The structure must be deinitialized
     afterwards using `gnutls_pcert_deinit()' ;

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pcert_import_x509_raw
----------------------------

 -- Function: int gnutls_pcert_import_x509_raw (gnutls_pcert_st *
          PCERT, const gnutls_datum_t* CERT, gnutls_x509_crt_fmt_t
          FORMAT, unsigned int FLAGS)
     PCERT: The pcert structure

     CERT: The raw certificate to be imported

     FORMAT: The format of the certificate

     FLAGS: zero for now

     This convenience function will import the given certificate to a
     `gnutls_pcert_st'  structure. The structure must be deinitialized
     afterwards using `gnutls_pcert_deinit()' ;

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pcert_list_import_x509_raw
---------------------------------

 -- Function: int gnutls_pcert_list_import_x509_raw (gnutls_pcert_st *
          PCERTS, unsigned int * PCERT_MAX, const gnutls_datum_t *
          DATA, gnutls_x509_crt_fmt_t FORMAT, unsigned int FLAGS)
     PCERTS: The structures to store the parsed certificate. Must not
     be initialized.

     PCERT_MAX: Initially must hold the maximum number of certs. It
     will be updated with the number of certs available.

     DATA: The certificates.

     FORMAT: One of DER or PEM.

     FLAGS: must be (0) or an OR'd sequence of
     gnutls_certificate_import_flags.

     This function will convert the given PEM encoded certificate list
     to the native gnutls_x509_crt_t format. The output will be stored
     in  `certs' .  They will be automatically initialized.

     If the Certificate is PEM encoded it should have a header of "X509
     CERTIFICATE", or "CERTIFICATE".

     *Returns:* the number of certificates read or a negative error
     value.

     *Since:* 3.0

gnutls_privkey_decrypt_data
---------------------------

 -- Function: int gnutls_privkey_decrypt_data (gnutls_privkey_t KEY,
          unsigned int FLAGS, const gnutls_datum_t * CIPHERTEXT,
          gnutls_datum_t * PLAINTEXT)
     KEY: Holds the key

     FLAGS: zero for now

     CIPHERTEXT: holds the data to be decrypted

     PLAINTEXT: will contain the decrypted data, allocated with
     `gnutls_malloc()'

     This function will decrypt the given data using the algorithm
     supported by the private key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_deinit
---------------------

 -- Function: void gnutls_privkey_deinit (gnutls_privkey_t KEY)
     KEY: The structure to be deinitialized

     This function will deinitialize a private key structure.

     *Since:* 2.12.0

gnutls_privkey_get_pk_algorithm
-------------------------------

 -- Function: int gnutls_privkey_get_pk_algorithm (gnutls_privkey_t
          KEY, unsigned int * BITS)
     KEY: should contain a `gnutls_privkey_t'  structure

     BITS: If set will return the number of bits of the parameters (may
     be NULL)

     This function will return the public key algorithm of a private
     key and if possible will return a number of bits that indicates
     the security parameter of the key.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

     *Since:* 2.12.0

gnutls_privkey_get_type
-----------------------

 -- Function: gnutls_privkey_type_t gnutls_privkey_get_type
          (gnutls_privkey_t KEY)
     KEY: should contain a `gnutls_privkey_t'  structure

     This function will return the type of the private key. This is
     actually the type of the subsystem used to set this private key.

     *Returns:* a member of the `gnutls_privkey_type_t'  enumeration on
     success, or a negative error code on error.

     *Since:* 2.12.0

gnutls_privkey_import_ext
-------------------------

 -- Function: int gnutls_privkey_import_ext (gnutls_privkey_t PKEY,
          gnutls_pk_algorithm_t PK, void* USERDATA,
          gnutls_privkey_sign_func SIGN_FUNC,
          gnutls_privkey_decrypt_func DECRYPT_FUNC, unsigned int FLAGS)
     PKEY: The private key

     PK: The public key algorithm

     USERDATA: private data to be provided to the callbacks

     SIGN_FUNC: callback for signature operations

     DECRYPT_FUNC: callback for decryption operations

     FLAGS: Flags for the import

     This function will associate the given callbacks with the
     `gnutls_privkey_t'  structure. At least one of the two callbacks
     must be non-null.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_privkey_import_openpgp
-----------------------------

 -- Function: int gnutls_privkey_import_openpgp (gnutls_privkey_t PKEY,
          gnutls_openpgp_privkey_t KEY, unsigned int FLAGS)
     PKEY: The private key

     KEY: The private key to be imported

     FLAGS: Flags for the import

     This function will import the given private key to the abstract
     `gnutls_privkey_t'  structure.

     The `gnutls_openpgp_privkey_t'  object must not be deallocated
     during the lifetime of this structure. The subkey set as preferred
     will be used, or the master key otherwise.

     `flags' might be zero or one of
     `GNUTLS_PRIVKEY_IMPORT_AUTO_RELEASE' and
     `GNUTLS_PRIVKEY_IMPORT_COPY' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_import_pkcs11
----------------------------

 -- Function: int gnutls_privkey_import_pkcs11 (gnutls_privkey_t PKEY,
          gnutls_pkcs11_privkey_t KEY, unsigned int FLAGS)
     PKEY: The private key

     KEY: The private key to be imported

     FLAGS: Flags for the import

     This function will import the given private key to the abstract
     `gnutls_privkey_t'  structure.

     The `gnutls_pkcs11_privkey_t'  object must not be deallocated
     during the lifetime of this structure.

     `flags' might be zero or one of
     `GNUTLS_PRIVKEY_IMPORT_AUTO_RELEASE' and
     `GNUTLS_PRIVKEY_IMPORT_COPY' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_import_x509
--------------------------

 -- Function: int gnutls_privkey_import_x509 (gnutls_privkey_t PKEY,
          gnutls_x509_privkey_t KEY, unsigned int FLAGS)
     PKEY: The private key

     KEY: The private key to be imported

     FLAGS: Flags for the import

     This function will import the given private key to the abstract
     `gnutls_privkey_t'  structure.

     The `gnutls_x509_privkey_t'  object must not be deallocated during
     the lifetime of this structure.

     `flags' might be zero or one of
     `GNUTLS_PRIVKEY_IMPORT_AUTO_RELEASE' and
     `GNUTLS_PRIVKEY_IMPORT_COPY' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_init
-------------------

 -- Function: int gnutls_privkey_init (gnutls_privkey_t * KEY)
     KEY: The structure to be initialized

     This function will initialize an private key structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_sign_data
------------------------

 -- Function: int gnutls_privkey_sign_data (gnutls_privkey_t SIGNER,
          gnutls_digest_algorithm_t HASH, unsigned int FLAGS, const
          gnutls_datum_t * DATA, gnutls_datum_t * SIGNATURE)
     SIGNER: Holds the key

     HASH: should be a digest algorithm

     FLAGS: should be 0 for now

     DATA: holds the data to be signed

     SIGNATURE: will contain the signature allocate with
     `gnutls_malloc()'

     This function will sign the given data using a signature algorithm
     supported by the private key. Signature algorithms are always used
     together with a hash functions.  Different hash functions may be
     used for the RSA algorithm, but only the SHA family for the DSA
     keys.

     Use `gnutls_pubkey_get_preferred_hash_algorithm()'  to determine
     the hash algorithm.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_privkey_sign_hash
------------------------

 -- Function: int gnutls_privkey_sign_hash (gnutls_privkey_t SIGNER,
          gnutls_digest_algorithm_t HASH_ALGO, unsigned int FLAGS,
          const gnutls_datum_t * HASH_DATA, gnutls_datum_t * SIGNATURE)
     SIGNER: Holds the signer's key

     HASH_ALGO: The hash algorithm used

     FLAGS: zero for now

     HASH_DATA: holds the data to be signed

     SIGNATURE: will contain newly allocated signature

     This function will sign the given hashed data using a signature
     algorithm supported by the private key. Signature algorithms are
     always used together with a hash functions.  Different hash
     functions may be used for the RSA algorithm, but only SHA-XXX for
     the DSA keys.

     Use `gnutls_pubkey_get_preferred_hash_algorithm()'  to determine
     the hash algorithm.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_deinit
--------------------

 -- Function: void gnutls_pubkey_deinit (gnutls_pubkey_t KEY)
     KEY: The structure to be deinitialized

     This function will deinitialize a public key structure.

     *Since:* 2.12.0

gnutls_pubkey_encrypt_data
--------------------------

 -- Function: int gnutls_pubkey_encrypt_data (gnutls_pubkey_t KEY,
          unsigned int FLAGS, const gnutls_datum_t * PLAINTEXT,
          gnutls_datum_t * CIPHERTEXT)
     KEY: Holds the public key

     FLAGS: should be 0 for now

     PLAINTEXT: The data to be encrypted

     CIPHERTEXT: contains the encrypted data

     This function will encrypt the given data, using the public key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pubkey_export
--------------------

 -- Function: int gnutls_pubkey_export (gnutls_pubkey_t KEY,
          gnutls_x509_crt_fmt_t FORMAT, void * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     KEY: Holds the certificate

     FORMAT: the format of output params. One of PEM or DER.

     OUTPUT_DATA: will contain a certificate PEM or DER encoded

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will export the public key to DER or PEM format.
     The contents of the exported data is the SubjectPublicKeyInfo
     X.509 structure.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.

     If the structure is PEM encoded, it will have a header of "BEGIN
     CERTIFICATE".

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

     *Since:* 2.12.0

gnutls_pubkey_get_key_id
------------------------

 -- Function: int gnutls_pubkey_get_key_id (gnutls_pubkey_t KEY,
          unsigned int FLAGS, unsigned char * OUTPUT_DATA, size_t *
          OUTPUT_DATA_SIZE)
     KEY: Holds the public key

     FLAGS: should be 0 for now

     OUTPUT_DATA: will contain the key ID

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     This function will return a unique ID the depends on the public
     key parameters. This ID can be used in checking whether a
     certificate corresponds to the given public key.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.  The output will normally be a SHA-1 hash output,
     which is 20 bytes.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

     *Since:* 2.12.0

gnutls_pubkey_get_key_usage
---------------------------

 -- Function: int gnutls_pubkey_get_key_usage (gnutls_pubkey_t KEY,
          unsigned int * USAGE)
     KEY: should contain a `gnutls_pubkey_t'  structure

     USAGE: If set will return the number of bits of the parameters
     (may be NULL)

     This function will return the key usage of the public key.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_get_openpgp_key_id
--------------------------------

 -- Function: int gnutls_pubkey_get_openpgp_key_id (gnutls_pubkey_t
          KEY, unsigned int FLAGS, unsigned char * OUTPUT_DATA, size_t
          * OUTPUT_DATA_SIZE, unsigned int * SUBKEY)
     KEY: Holds the public key

     FLAGS: should be 0 for now

     OUTPUT_DATA: will contain the key ID

     OUTPUT_DATA_SIZE: holds the size of output_data (and will be
     replaced by the actual size of parameters)

     SUBKEY: Will be non zero if the key ID corresponds to a subkey

     This function will return a unique ID the depends on the public
     key parameters. This ID can be used in checking whether a
     certificate corresponds to the given public key.

     If the buffer provided is not long enough to hold the output, then
     *output_data_size is updated and `GNUTLS_E_SHORT_MEMORY_BUFFER'
     will be returned.  The output will normally be a SHA-1 hash output,
     which is 20 bytes.

     *Returns:* In case of failure a negative error code will be
     returned, and 0 on success.

     *Since:* 3.0

gnutls_pubkey_get_pk_algorithm
------------------------------

 -- Function: int gnutls_pubkey_get_pk_algorithm (gnutls_pubkey_t KEY,
          unsigned int * BITS)
     KEY: should contain a `gnutls_pubkey_t'  structure

     BITS: If set will return the number of bits of the parameters (may
     be NULL)

     This function will return the public key algorithm of a public key
     and if possible will return a number of bits that indicates the
     security parameter of the key.

     *Returns:* a member of the `gnutls_pk_algorithm_t'  enumeration on
     success, or a negative error code on error.

     *Since:* 2.12.0

gnutls_pubkey_get_pk_dsa_raw
----------------------------

 -- Function: int gnutls_pubkey_get_pk_dsa_raw (gnutls_pubkey_t KEY,
          gnutls_datum_t * P, gnutls_datum_t * Q, gnutls_datum_t * G,
          gnutls_datum_t * Y)
     KEY: Holds the public key

     P: will hold the p

     Q: will hold the q

     G: will hold the g

     Y: will hold the y

     This function will export the DSA public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.12.0

gnutls_pubkey_get_pk_ecc_raw
----------------------------

 -- Function: int gnutls_pubkey_get_pk_ecc_raw (gnutls_pubkey_t KEY,
          gnutls_ecc_curve_t * CURVE, gnutls_datum_t * X,
          gnutls_datum_t * Y)
     KEY: Holds the public key

     CURVE: will hold the curve

     X: will hold x

     Y: will hold y

     This function will export the ECC public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 3.0

gnutls_pubkey_get_pk_ecc_x962
-----------------------------

 -- Function: int gnutls_pubkey_get_pk_ecc_x962 (gnutls_pubkey_t KEY,
          gnutls_datum_t* PARAMETERS, gnutls_datum_t * ECPOINT)
     KEY: Holds the public key

     PARAMETERS: DER encoding of an ANSI X9.62 parameters

     ECPOINT: DER encoding of ANSI X9.62 ECPoint

     This function will export the ECC public key's parameters found in
     the given certificate.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 3.0

gnutls_pubkey_get_pk_rsa_raw
----------------------------

 -- Function: int gnutls_pubkey_get_pk_rsa_raw (gnutls_pubkey_t KEY,
          gnutls_datum_t * M, gnutls_datum_t * E)
     KEY: Holds the certificate

     M: will hold the modulus

     E: will hold the public exponent

     This function will export the RSA public key's parameters found in
     the given structure.  The new parameters will be allocated using
     `gnutls_malloc()'  and will be stored in the appropriate datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.

     *Since:* 2.12.0

gnutls_pubkey_get_preferred_hash_algorithm
------------------------------------------

 -- Function: int gnutls_pubkey_get_preferred_hash_algorithm
          (gnutls_pubkey_t KEY, gnutls_digest_algorithm_t * HASH,
          unsigned int * MAND)
     KEY: Holds the certificate

     HASH: The result of the call with the hash algorithm used for
     signature

     MAND: If non zero it means that the algorithm MUST use this hash.
     May be NULL.

     This function will read the certifcate and return the appropriate
     digest algorithm to use for signing with this certificate. Some
     certificates (i.e.  DSA might not be able to sign without the
     preferred algorithm).

     *Returns:* the 0 if the hash algorithm is found. A negative error
     code is returned on error.

     *Since:* 2.12.0

gnutls_pubkey_get_verify_algorithm
----------------------------------

 -- Function: int gnutls_pubkey_get_verify_algorithm (gnutls_pubkey_t
          KEY, const gnutls_datum_t * SIGNATURE,
          gnutls_digest_algorithm_t * HASH)
     KEY: Holds the certificate

     SIGNATURE: contains the signature

     HASH: The result of the call with the hash algorithm used for
     signature

     This function will read the certifcate and the signed data to
     determine the hash algorithm used to generate the signature.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import
--------------------

 -- Function: int gnutls_pubkey_import (gnutls_pubkey_t KEY, const
          gnutls_datum_t * DATA, gnutls_x509_crt_fmt_t FORMAT)
     KEY: The structure to store the parsed public key.

     DATA: The DER or PEM encoded certificate.

     FORMAT: One of DER or PEM

     This function will import the provided public key in a
     SubjectPublicKeyInfo X.509 structure to a native `gnutls_pubkey_t'
     structure. The output will be stored in  `key' . If the public
     key is PEM encoded it should have a header of "PUBLIC KEY".

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_dsa_raw
----------------------------

 -- Function: int gnutls_pubkey_import_dsa_raw (gnutls_pubkey_t KEY,
          const gnutls_datum_t * P, const gnutls_datum_t * Q, const
          gnutls_datum_t * G, const gnutls_datum_t * Y)
     KEY: The structure to store the parsed key

     P: holds the p

     Q: holds the q

     G: holds the g

     Y: holds the y

     This function will convert the given DSA raw parameters to the
     native `gnutls_pubkey_t'  format.  The output will be stored in
     `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_ecc_raw
----------------------------

 -- Function: int gnutls_pubkey_import_ecc_raw (gnutls_pubkey_t KEY,
          gnutls_ecc_curve_t CURVE, const gnutls_datum_t * X, const
          gnutls_datum_t * Y)
     KEY: The structure to store the parsed key

     CURVE: holds the curve

     X: holds the x

     Y: holds the y

     This function will convert the given elliptic curve parameters to a
     `gnutls_pubkey_t' .  The output will be stored in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pubkey_import_ecc_x962
-----------------------------

 -- Function: int gnutls_pubkey_import_ecc_x962 (gnutls_pubkey_t KEY,
          const gnutls_datum_t * PARAMETERS, const gnutls_datum_t *
          ECPOINT)
     KEY: The structure to store the parsed key

     PARAMETERS: DER encoding of an ANSI X9.62 parameters

     ECPOINT: DER encoding of ANSI X9.62 ECPoint

     This function will convert the given elliptic curve parameters to a
     `gnutls_pubkey_t' .  The output will be stored in  `key' .

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 3.0

gnutls_pubkey_import_openpgp
----------------------------

 -- Function: int gnutls_pubkey_import_openpgp (gnutls_pubkey_t KEY,
          gnutls_openpgp_crt_t CRT, unsigned int FLAGS)
     KEY: The public key

     CRT: The certificate to be imported

     FLAGS: should be zero

     Imports a public key from an openpgp key. This function will import
     the given public key to the abstract `gnutls_pubkey_t' structure.
     The subkey set as preferred will be imported or the master key
     otherwise.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_pkcs11
---------------------------

 -- Function: int gnutls_pubkey_import_pkcs11 (gnutls_pubkey_t KEY,
          gnutls_pkcs11_obj_t OBJ, unsigned int FLAGS)
     KEY: The public key

     OBJ: The parameters to be imported

     FLAGS: should be zero

     Imports a public key from a pkcs11 key. This function will import
     the given public key to the abstract `gnutls_pubkey_t'  structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_pkcs11_url
-------------------------------

 -- Function: int gnutls_pubkey_import_pkcs11_url (gnutls_pubkey_t KEY,
          const char * URL, unsigned int FLAGS)
     KEY: A key of type `gnutls_pubkey_t'

     URL: A PKCS 11 url

     FLAGS: One of GNUTLS_PKCS11_OBJ_* flags

     This function will import a PKCS 11 certificate to a
     `gnutls_pubkey_t' structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_privkey
----------------------------

 -- Function: int gnutls_pubkey_import_privkey (gnutls_pubkey_t KEY,
          gnutls_privkey_t PKEY, unsigned int USAGE, unsigned int FLAGS)
     KEY: The public key

     PKEY: The private key

     USAGE: GNUTLS_KEY_* key usage flags.

     FLAGS: should be zero

     Imports the public key from a private.  This function will import
     the given public key to the abstract `gnutls_pubkey_t'  structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_import_rsa_raw
----------------------------

 -- Function: int gnutls_pubkey_import_rsa_raw (gnutls_pubkey_t KEY,
          const gnutls_datum_t * M, const gnutls_datum_t * E)
     KEY: Is a structure will hold the parameters

     M: holds the modulus

     E: holds the public exponent

     This function will replace the parameters in the given structure.
     The new parameters should be stored in the appropriate
     gnutls_datum.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, or an negative error
     code.

     *Since:* 2.12.0

gnutls_pubkey_import_x509
-------------------------

 -- Function: int gnutls_pubkey_import_x509 (gnutls_pubkey_t KEY,
          gnutls_x509_crt_t CRT, unsigned int FLAGS)
     KEY: The public key

     CRT: The certificate to be imported

     FLAGS: should be zero

     This function will import the given public key to the abstract
     `gnutls_pubkey_t'  structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_init
------------------

 -- Function: int gnutls_pubkey_init (gnutls_pubkey_t * KEY)
     KEY: The structure to be initialized

     This function will initialize an public key structure.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_set_key_usage
---------------------------

 -- Function: int gnutls_pubkey_set_key_usage (gnutls_pubkey_t KEY,
          unsigned int USAGE)
     KEY: a certificate of type `gnutls_x509_crt_t'

     USAGE: an ORed sequence of the GNUTLS_KEY_* elements.

     This function will set the key usage flags of the public key. This
     is only useful if the key is to be exported to a certificate or
     certificate request.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_pubkey_verify_data
-------------------------

 -- Function: int gnutls_pubkey_verify_data (gnutls_pubkey_t PUBKEY,
          unsigned int FLAGS, const gnutls_datum_t * DATA, const
          gnutls_datum_t * SIGNATURE)
     PUBKEY: Holds the public key

     FLAGS: should be 0 for now

     DATA: holds the signed data

     SIGNATURE: contains the signature

     This function will verify the given signed data, using the
     parameters from the certificate.

     *Returns:* In case of a verification failure
     `GNUTLS_E_PK_SIG_VERIFY_FAILED' is returned, and zero or positive
     code on success.

     *Since:* 2.12.0

gnutls_pubkey_verify_data2
--------------------------

 -- Function: int gnutls_pubkey_verify_data2 (gnutls_pubkey_t PUBKEY,
          gnutls_sign_algorithm_t ALGO, unsigned int FLAGS, const
          gnutls_datum_t * DATA, const gnutls_datum_t * SIGNATURE)
     PUBKEY: Holds the public key

     ALGO: The signature algorithm used

     FLAGS: should be 0 for now

     DATA: holds the signed data

     SIGNATURE: contains the signature

     This function will verify the given signed data, using the
     parameters from the certificate.

     *Returns:* In case of a verification failure
     `GNUTLS_E_PK_SIG_VERIFY_FAILED' is returned, and zero or positive
     code on success.

     *Since:* 3.0

gnutls_pubkey_verify_hash
-------------------------

 -- Function: int gnutls_pubkey_verify_hash (gnutls_pubkey_t KEY,
          unsigned int FLAGS, const gnutls_datum_t * HASH, const
          gnutls_datum_t * SIGNATURE)
     KEY: Holds the public key

     FLAGS: should be 0 for now

     HASH: holds the hash digest to be verified

     SIGNATURE: contains the signature

     This function will verify the given signed digest, using the
     parameters from the public key. Use `gnutls_pubkey_verify_hash2()'
     instead of this function.

     *Returns:* In case of a verification failure
     `GNUTLS_E_PK_SIG_VERIFY_FAILED' is returned, and zero or positive
     code on success.

     *Since:* 2.12.0

gnutls_pubkey_verify_hash2
--------------------------

 -- Function: int gnutls_pubkey_verify_hash2 (gnutls_pubkey_t KEY,
          gnutls_sign_algorithm_t ALGO, unsigned int FLAGS, const
          gnutls_datum_t * HASH, const gnutls_datum_t * SIGNATURE)
     KEY: Holds the public key

     ALGO: The signature algorithm used

     FLAGS: should be 0 for now

     HASH: holds the hash digest to be verified

     SIGNATURE: contains the signature

     This function will verify the given signed digest, using the
     parameters from the public key.

     *Returns:* In case of a verification failure
     `GNUTLS_E_PK_SIG_VERIFY_FAILED' is returned, and zero or positive
     code on success.

     *Since:* 3.0

gnutls_x509_crl_privkey_sign
----------------------------

 -- Function: int gnutls_x509_crl_privkey_sign (gnutls_x509_crl_t CRL,
          gnutls_x509_crt_t ISSUER, gnutls_privkey_t ISSUER_KEY,
          gnutls_digest_algorithm_t DIG, unsigned int FLAGS)
     CRL: should contain a gnutls_x509_crl_t structure

     ISSUER: is the certificate of the certificate issuer

     ISSUER_KEY: holds the issuer's private key

     DIG: The message digest to use. GNUTLS_DIG_SHA1 is the safe choice
     unless you know what you're doing.

     FLAGS: must be 0

     This function will sign the CRL with the issuer's private key, and
     will copy the issuer's information into the CRL.

     This must be the last step in a certificate CRL since all the
     previously set parameters are now signed.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     Since 2.12.0

gnutls_x509_crq_privkey_sign
----------------------------

 -- Function: int gnutls_x509_crq_privkey_sign (gnutls_x509_crq_t CRQ,
          gnutls_privkey_t KEY, gnutls_digest_algorithm_t DIG, unsigned
          int FLAGS)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     KEY: holds a private key

     DIG: The message digest to use, i.e., `GNUTLS_DIG_SHA1'

     FLAGS: must be 0

     This function will sign the certificate request with a private key.
     This must be the same key as the one used in
     `gnutls_x509_crt_set_key()'  since a certificate request is self
     signed.

     This must be the last step in a certificate request generation
     since all the previously set parameters are now signed.

     *Returns:* `GNUTLS_E_SUCCESS'  on success, otherwise a negative
     error code.  `GNUTLS_E_ASN1_VALUE_NOT_FOUND'  is returned if you
     didn't set all information in the certificate request (e.g., the
     version using `gnutls_x509_crq_set_version()' ).

     *Since:* 2.12.0

gnutls_x509_crq_set_pubkey
--------------------------

 -- Function: int gnutls_x509_crq_set_pubkey (gnutls_x509_crq_t CRQ,
          gnutls_pubkey_t KEY)
     CRQ: should contain a `gnutls_x509_crq_t'  structure

     KEY: holds a public key

     This function will set the public parameters from the given public
     key to the request.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

gnutls_x509_crt_privkey_sign
----------------------------

 -- Function: int gnutls_x509_crt_privkey_sign (gnutls_x509_crt_t CRT,
          gnutls_x509_crt_t ISSUER, gnutls_privkey_t ISSUER_KEY,
          gnutls_digest_algorithm_t DIG, unsigned int FLAGS)
     CRT: a certificate of type `gnutls_x509_crt_t'

     ISSUER: is the certificate of the certificate issuer

     ISSUER_KEY: holds the issuer's private key

     DIG: The message digest to use, `GNUTLS_DIG_SHA1'  is a safe choice

     FLAGS: must be 0

     This function will sign the certificate with the issuer's private
     key, and will copy the issuer's information into the certificate.

     This must be the last step in a certificate generation since all
     the previously set parameters are now signed.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

gnutls_x509_crt_set_pubkey
--------------------------

 -- Function: int gnutls_x509_crt_set_pubkey (gnutls_x509_crt_t CRT,
          gnutls_pubkey_t KEY)
     CRT: should contain a `gnutls_x509_crt_t'  structure

     KEY: holds a public key

     This function will set the public parameters from the given public
     key to the request.

     *Returns:* On success, `GNUTLS_E_SUCCESS'  (0) is returned,
     otherwise a negative error value.

     *Since:* 2.12.0

