x509: GnuTLS API Reference Manual

## x509 x509 |

## Functions

void | gnutls_pkcs7_deinit ()
int | gnutls_pkcs7_delete_crl ()
int | gnutls_pkcs7_delete_crt ()
int | gnutls_pkcs7_export ()
int | gnutls_pkcs7_export2 ()
int | gnutls_pkcs7_get_crl_count ()
int | gnutls_pkcs7_get_crl_raw ()
int | gnutls_pkcs7_get_crt_count ()
int | gnutls_pkcs7_get_crt_raw ()
int | gnutls_pkcs7_import ()
int | gnutls_pkcs7_init ()
int | gnutls_pkcs7_set_crl ()
int | gnutls_pkcs7_set_crl_raw ()
int | gnutls_pkcs7_set_crt ()
int | gnutls_pkcs7_set_crt_raw ()
int | gnutls_x509_crl_check_issuer ()
void | gnutls_x509_crl_deinit ()
int | gnutls_x509_crl_export ()
int | gnutls_x509_crl_export2 ()
int | gnutls_x509_crl_get_authority_key_gn_serial ()
int | gnutls_x509_crl_get_authority_key_id ()
int | gnutls_x509_crl_get_crt_count ()
int | gnutls_x509_crl_get_crt_serial ()
int | gnutls_x509_crl_get_dn_oid ()
int | gnutls_x509_crl_get_extension_data ()
int | gnutls_x509_crl_get_extension_info ()
int | gnutls_x509_crl_get_extension_oid ()
int | gnutls_x509_crl_get_issuer_dn ()
int | gnutls_x509_crl_get_issuer_dn_by_oid ()
time_t | gnutls_x509_crl_get_next_update ()
int | gnutls_x509_crl_get_number ()
int | gnutls_x509_crl_get_raw_issuer_dn ()
int | gnutls_x509_crl_get_signature ()
int | gnutls_x509_crl_get_signature_algorithm ()
time_t | gnutls_x509_crl_get_this_update ()
int | gnutls_x509_crl_get_version ()
int | gnutls_x509_crl_import ()
int | gnutls_x509_crl_init ()
int | gnutls_x509_crl_list_import ()
int | gnutls_x509_crl_list_import2 ()
int | gnutls_x509_crl_print ()
int | gnutls_x509_crl_set_authority_key_id ()
int | gnutls_x509_crl_set_crt ()
int | gnutls_x509_crl_set_crt_serial ()
int | gnutls_x509_crl_set_next_update ()
int | gnutls_x509_crl_set_number ()
int | gnutls_x509_crl_set_this_update ()
int | gnutls_x509_crl_set_version ()
int | gnutls_x509_crl_sign2 ()
int | gnutls_x509_crl_verify ()
void | gnutls_x509_crq_deinit ()
int | gnutls_x509_crq_export ()
int | gnutls_x509_crq_export2 ()
int | gnutls_x509_crq_get_attribute_by_oid ()
int | gnutls_x509_crq_get_attribute_data ()
int | gnutls_x509_crq_get_attribute_info ()
int | gnutls_x509_crq_get_basic_constraints ()
int | gnutls_x509_crq_get_challenge_password ()
int | gnutls_x509_crq_get_dn ()
int | gnutls_x509_crq_get_dn_by_oid ()
int | gnutls_x509_crq_get_dn_oid ()
int | gnutls_x509_crq_get_extension_by_oid ()
int | gnutls_x509_crq_get_extension_data ()
int | gnutls_x509_crq_get_extension_info ()
int | gnutls_x509_crq_get_key_id ()
int | gnutls_x509_crq_get_key_purpose_oid ()
int | gnutls_x509_crq_get_key_rsa_raw ()
int | gnutls_x509_crq_get_key_usage ()
int | gnutls_x509_crq_get_pk_algorithm ()
int | gnutls_x509_crq_get_private_key_usage_period ()
int | gnutls_x509_crq_get_subject_alt_name ()
int | gnutls_x509_crq_get_subject_alt_othername_oid ()
int | gnutls_x509_crq_get_version ()
int | gnutls_x509_crq_import ()
int | gnutls_x509_crq_init ()
int | gnutls_x509_crq_print ()
int | gnutls_x509_crq_set_attribute_by_oid ()
int | gnutls_x509_crq_set_basic_constraints ()
int | gnutls_x509_crq_set_challenge_password ()
int | gnutls_x509_crq_set_dn_by_oid ()
int | gnutls_x509_crq_set_key ()
int | gnutls_x509_crq_set_key_purpose_oid ()
int | gnutls_x509_crq_set_key_rsa_raw ()
int | gnutls_x509_crq_set_key_usage ()
int | gnutls_x509_crq_set_private_key_usage_period ()
int | gnutls_x509_crq_set_subject_alt_name ()
int | gnutls_x509_crq_set_version ()
int | gnutls_x509_crq_sign2 ()
int | gnutls_x509_crq_verify ()
int | gnutls_x509_crt_check_hostname ()
int | gnutls_x509_crt_check_issuer ()
int | gnutls_x509_crt_check_revocation ()
int | gnutls_x509_crt_cpy_crl_dist_points ()
void | gnutls_x509_crt_deinit ()
int | gnutls_x509_crt_export ()
int | gnutls_x509_crt_export2 ()
time_t | gnutls_x509_crt_get_activation_time ()
int | gnutls_x509_crt_get_authority_info_access ()
int | gnutls_x509_crt_get_authority_key_gn_serial ()
int | gnutls_x509_crt_get_authority_key_id ()
int | gnutls_x509_crt_get_basic_constraints ()
int | gnutls_x509_crt_get_ca_status ()
int | gnutls_x509_crt_get_crl_dist_points ()
int | gnutls_x509_crt_get_dn ()
int | gnutls_x509_crt_get_dn_by_oid ()
int | gnutls_x509_crt_get_dn_oid ()
time_t | gnutls_x509_crt_get_expiration_time ()
int | gnutls_x509_crt_get_extension_by_oid ()
int | gnutls_x509_crt_get_extension_data ()
int | gnutls_x509_crt_get_extension_info ()
int | gnutls_x509_crt_get_extension_oid ()
int | gnutls_x509_crt_get_fingerprint ()
int | gnutls_x509_crt_get_issuer ()
int | gnutls_x509_crt_get_issuer_alt_name ()
int | gnutls_x509_crt_get_issuer_alt_name2 ()
int | gnutls_x509_crt_get_issuer_alt_othername_oid ()
int | gnutls_x509_crt_get_issuer_dn ()
int | gnutls_x509_crt_get_issuer_dn_by_oid ()
int | gnutls_x509_crt_get_issuer_dn_oid ()
int | gnutls_x509_crt_get_issuer_unique_id ()
int | gnutls_x509_crt_get_key_id ()
int | gnutls_x509_crt_get_key_purpose_oid ()
int | gnutls_x509_crt_get_key_usage ()
int | gnutls_x509_crt_get_pk_algorithm ()
int | gnutls_x509_crt_get_pk_dsa_raw ()
int | gnutls_x509_crt_get_pk_rsa_raw ()
int | gnutls_x509_crt_get_policy ()
int | gnutls_x509_crt_get_private_key_usage_period ()
int | gnutls_x509_crt_get_proxy ()
int | gnutls_x509_crt_get_raw_dn ()
int | gnutls_x509_crt_get_raw_issuer_dn ()
int | gnutls_x509_crt_get_serial ()
int | gnutls_x509_crt_get_signature ()
int | gnutls_x509_crt_get_signature_algorithm ()
int | gnutls_x509_crt_get_subject ()
int | gnutls_x509_crt_get_subject_alt_name ()
int | gnutls_x509_crt_get_subject_alt_name2 ()
int | gnutls_x509_crt_get_subject_alt_othername_oid ()
int | gnutls_x509_crt_get_subject_key_id ()
int | gnutls_x509_crt_get_subject_unique_id ()
int | gnutls_x509_crt_get_version ()
int | gnutls_x509_crt_import ()
int | gnutls_x509_crt_init ()
int | gnutls_x509_crt_list_import ()
int | gnutls_x509_crt_list_import2 ()
int | gnutls_x509_crt_list_verify ()
int | gnutls_x509_crt_print ()
int | gnutls_x509_crt_set_activation_time ()
int | gnutls_x509_crt_set_authority_info_access ()
int | gnutls_x509_crt_set_authority_key_id ()
int | gnutls_x509_crt_set_basic_constraints ()
int | gnutls_x509_crt_set_ca_status ()
int | gnutls_x509_crt_set_crl_dist_points ()
int | gnutls_x509_crt_set_crl_dist_points2 ()
int | gnutls_x509_crt_set_crq ()
int | gnutls_x509_crt_set_crq_extensions ()
int | gnutls_x509_crt_set_dn_by_oid ()
int | gnutls_x509_crt_set_expiration_time ()
int | gnutls_x509_crt_set_extension_by_oid ()
int | gnutls_x509_crt_set_issuer_dn_by_oid ()
int | gnutls_x509_crt_set_key ()
int | gnutls_x509_crt_set_key_purpose_oid ()
int | gnutls_x509_crt_set_key_usage ()
void | gnutls_x509_crt_set_pin_function ()
int | gnutls_x509_crt_set_policy ()
int | gnutls_x509_crt_set_private_key_usage_period ()
int | gnutls_x509_crt_set_proxy ()
int | gnutls_x509_crt_set_proxy_dn ()
int | gnutls_x509_crt_set_serial ()
int | gnutls_x509_crt_set_subject_alt_name ()
int | gnutls_x509_crt_set_subject_alternative_name ()
int | gnutls_x509_crt_set_subject_key_id ()
int | gnutls_x509_crt_set_version ()
int | gnutls_x509_crt_sign ()
int | gnutls_x509_crt_sign2 ()
int | gnutls_x509_crt_verify ()
void | gnutls_x509_dn_deinit ()
int | gnutls_x509_dn_export ()
int | gnutls_x509_dn_export2 ()
int | gnutls_x509_dn_get_rdn_ava ()
int | gnutls_x509_dn_import ()
int | gnutls_x509_dn_init ()
int | gnutls_x509_dn_oid_known ()
const char * | gnutls_x509_dn_oid_name ()
void | gnutls_x509_policy_release ()
int | gnutls_x509_privkey_cpy ()
void | gnutls_x509_privkey_deinit ()
int | gnutls_x509_privkey_export ()
int | gnutls_x509_privkey_export2 ()
int | gnutls_x509_privkey_export2_pkcs8 ()
int | gnutls_x509_privkey_export_dsa_raw ()
int | gnutls_x509_privkey_export_ecc_raw ()
int | gnutls_x509_privkey_export_pkcs8 ()
int | gnutls_x509_privkey_export_rsa_raw ()
int | gnutls_x509_privkey_export_rsa_raw2 ()
int | gnutls_x509_privkey_fix ()
int | gnutls_x509_privkey_generate ()
int | gnutls_x509_privkey_get_key_id ()
int | gnutls_x509_privkey_get_pk_algorithm ()
int | gnutls_x509_privkey_get_pk_algorithm2 ()
int | gnutls_x509_privkey_import ()
int | gnutls_x509_privkey_import2 ()
int | gnutls_x509_privkey_import_dsa_raw ()
int | gnutls_x509_privkey_import_ecc_raw ()
int | gnutls_x509_privkey_import_openssl ()
int | gnutls_x509_privkey_import_pkcs8 ()
int | gnutls_x509_privkey_import_rsa_raw ()
int | gnutls_x509_privkey_import_rsa_raw2 ()
int | gnutls_x509_privkey_init ()
gnutls_sec_param_t | gnutls_x509_privkey_sec_param ()
int | gnutls_x509_privkey_verify_params ()
int | gnutls_x509_rdn_get ()
int | gnutls_x509_rdn_get_by_oid ()
int | gnutls_x509_rdn_get_oid ()
int | gnutls_x509_trust_list_add_cas ()
int | gnutls_x509_trust_list_add_crls ()
int | gnutls_x509_trust_list_add_named_crt ()
int | gnutls_x509_trust_list_add_system_trust ()
int | gnutls_x509_trust_list_add_trust_file ()
int | gnutls_x509_trust_list_add_trust_mem ()
void | gnutls_x509_trust_list_deinit ()
int | gnutls_x509_trust_list_get_issuer ()
int | gnutls_x509_trust_list_init ()
int | gnutls_x509_trust_list_verify_crt ()
int | gnutls_x509_trust_list_verify_named_crt ()

## Types and Values

#define | GNUTLS_CRL_REASON_SUPERSEEDED
#define | GNUTLS_FSAN_APPEND
#define | GNUTLS_FSAN_SET
#define | GNUTLS_KP_ANY
#define | GNUTLS_KP_CODE_SIGNING
#define | GNUTLS_KP_EMAIL_PROTECTION
#define | GNUTLS_KP_IPSEC_IKE
#define | GNUTLS_KP_MS_SMART_CARD_LOGON
#define | GNUTLS_KP_OCSP_SIGNING
#define | GNUTLS_KP_TIME_STAMPING
#define | GNUTLS_KP_TLS_WWW_CLIENT
#define | GNUTLS_KP_TLS_WWW_SERVER
#define | GNUTLS_MAX_QUALIFIERS
#define | GNUTLS_OID_AD_CAISSUERS
#define | GNUTLS_OID_AD_OCSP
#define | GNUTLS_OID_AIA
#define | GNUTLS_OID_LDAP_DC
#define | GNUTLS_OID_LDAP_UID
#define | GNUTLS_OID_PKCS9_EMAIL
#define | GNUTLS_OID_PKIX_COUNTRY_OF_CITIZENSHIP
#define | GNUTLS_OID_PKIX_COUNTRY_OF_RESIDENCE
#define | GNUTLS_OID_PKIX_DATE_OF_BIRTH
#define | GNUTLS_OID_PKIX_GENDER
#define | GNUTLS_OID_PKIX_PLACE_OF_BIRTH
#define | GNUTLS_OID_X520_COMMON_NAME
#define | GNUTLS_OID_X520_COUNTRY_NAME
#define | GNUTLS_OID_X520_DN_QUALIFIER
#define | GNUTLS_OID_X520_GENERATION_QUALIFIER
#define | GNUTLS_OID_X520_GIVEN_NAME
#define | GNUTLS_OID_X520_INITIALS
#define | GNUTLS_OID_X520_LOCALITY_NAME
#define | GNUTLS_OID_X520_NAME
#define | GNUTLS_OID_X520_ORGANIZATIONAL_UNIT_NAME
#define | GNUTLS_OID_X520_ORGANIZATION_NAME
#define | GNUTLS_OID_X520_POSTALCODE
#define | GNUTLS_OID_X520_PSEUDONYM
#define | GNUTLS_OID_X520_STATE_OR_PROVINCE_NAME
#define | GNUTLS_OID_X520_SURNAME
#define | GNUTLS_OID_X520_TITLE
#define | GNUTLS_PKCS8_PLAIN
#define | GNUTLS_PKCS8_USE_PKCS12_3DES
#define | GNUTLS_PKCS8_USE_PKCS12_ARCFOUR
#define | GNUTLS_PKCS8_USE_PKCS12_RC2_40
#define | GNUTLS_TL_VERIFY_CRL
#define | GNUTLS_X509_DN_OID_RETURN_OID
enum | gnutls_certificate_import_flags
enum | gnutls_certificate_verify_flags
enum | gnutls_info_access_what_t
| gnutls_pkcs7_int
typedef | gnutls_pkcs7_t
enum | gnutls_pkcs_encrypt_flags_t
#define | gnutls_x509_crl_get_certificate
#define | gnutls_x509_crl_get_certificate_count
enum | gnutls_x509_crl_reason_flags_t
typedef | gnutls_x509_dn_t
enum | gnutls_x509_qualifier_t
typedef | gnutls_x509_trust_list_t

## Description

## Functions

### gnutls_pkcs7_deinit ()

    void
    gnutls_pkcs7_deinit (gnutls_pkcs7_t pkcs7);

This function will deinitialize a PKCS7 structure.

#### Parameters

pkcs7 | The structure to be initialized |

### gnutls_pkcs7_delete_crl ()

    int
    gnutls_pkcs7_delete_crl (gnutls_pkcs7_t pkcs7,
                             int indx);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
indx | the index of the crl to delete |

#### Returns

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

### gnutls_pkcs7_delete_crt ()

    int
    gnutls_pkcs7_delete_crt (gnutls_pkcs7_t pkcs7,
                             int indx);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
indx | the index of the certificate to delete |

#### Returns

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

### gnutls_pkcs7_export ()

    int
    gnutls_pkcs7_export (gnutls_pkcs7_t pkcs7,
                         gnutls_x509_crt_fmt_t format,
                         void *output_data,
                         size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_pkcs7_export2 ()

    int
    gnutls_pkcs7_export2 (gnutls_pkcs7_t pkcs7,
                          gnutls_x509_crt_fmt_t format,
                          gnutls_datum_t *out);

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

The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

pkcs7 | Holds the pkcs7 structure |
format | the format of output params. One of PEM or DER. |
out | will contain a structure PEM or DER encoded |

#### Returns

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

Since: 3.1.3

### gnutls_pkcs7_get_crl_count ()

    int
    gnutls_pkcs7_get_crl_count (gnutls_pkcs7_t pkcs7);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |

#### Returns

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

### gnutls_pkcs7_get_crl_raw ()

    int
    gnutls_pkcs7_get_crl_raw (gnutls_pkcs7_t pkcs7,
                              int indx,
                              void *crl,
                              size_t *crl_size);

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

#### Parameters

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 |

#### 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 ()

    int
    gnutls_pkcs7_get_crt_count (gnutls_pkcs7_t pkcs7);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |

#### Returns

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

### gnutls_pkcs7_get_crt_raw ()

    int
    gnutls_pkcs7_get_crt_raw (gnutls_pkcs7_t pkcs7,
                              int indx,
                              void *certificate,
                              size_t *certificate_size);

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.

#### Parameters

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 |

#### 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 ()

    int
    gnutls_pkcs7_import (gnutls_pkcs7_t pkcs7,
                         const gnutls_datum_t *data,
                         gnutls_x509_crt_fmt_t format);

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".

#### Parameters

pkcs7 | The structure to store the parsed PKCS7. |
data | The DER or PEM encoded PKCS7. |
format | One of DER or PEM |

#### Returns

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

### gnutls_pkcs7_init ()

    int
    gnutls_pkcs7_init (gnutls_pkcs7_t *pkcs7);

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

#### Parameters

pkcs7 | The structure to be initialized |

#### Returns

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

### gnutls_pkcs7_set_crl ()

    int
    gnutls_pkcs7_set_crl (gnutls_pkcs7_t pkcs7,
                          gnutls_x509_crl_t crl);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
crl | the DER encoded crl to be added |

#### Returns

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

### gnutls_pkcs7_set_crl_raw ()

    int
    gnutls_pkcs7_set_crl_raw (gnutls_pkcs7_t pkcs7,
                              const gnutls_datum_t *crl);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
crl | the DER encoded crl to be added |

#### Returns

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

### gnutls_pkcs7_set_crt ()

    int
    gnutls_pkcs7_set_crt (gnutls_pkcs7_t pkcs7,
                          gnutls_x509_crt_t crt);

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()` .

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
crt | the certificate to be copied. |

#### Returns

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

### gnutls_pkcs7_set_crt_raw ()

    int
    gnutls_pkcs7_set_crt_raw (gnutls_pkcs7_t pkcs7,
                              const gnutls_datum_t *crt);

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

#### Parameters

pkcs7 | should contain a gnutls_pkcs7_t structure |
crt | the DER encoded certificate to be added |

#### Returns

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

### gnutls_x509_crl_check_issuer ()

    int
    gnutls_x509_crl_check_issuer (gnutls_x509_crl_t crl,
                                  gnutls_x509_crt_t issuer);

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

#### Parameters

crl | is the CRL to be checked |
issuer | is the certificate of a possible issuer |

#### Returns

true (1) if the given CRL was issued by the given issuer, and false (0) if not.

### gnutls_x509_crl_deinit ()

    void
    gnutls_x509_crl_deinit (gnutls_x509_crl_t crl);

This function will deinitialize a CRL structure.

#### Parameters

crl | The structure to be deinitialized |

### gnutls_x509_crl_export ()

    int
    gnutls_x509_crl_export (gnutls_x509_crl_t crl,
                            gnutls_x509_crt_fmt_t format,
                            void *output_data,
                            size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_x509_crl_export2 ()

    int
    gnutls_x509_crl_export2 (gnutls_x509_crl_t crl,
                             gnutls_x509_crt_fmt_t format,
                             gnutls_datum_t *out);

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

The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

crl | Holds the revocation list |
format | the format of output params. One of PEM or DER. |
out | will contain a private key PEM or DER encoded |

#### Returns

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

Since 3.1.3

### gnutls_x509_crl_get_authority_key_gn_serial ()

    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);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### Returns

Returns 0 on success, or an error code.

Since: 3.0

### gnutls_x509_crl_get_authority_key_id ()

    int
    gnutls_x509_crl_get_authority_key_id (gnutls_x509_crl_t crl,
                                          void *id,
                                          size_t *id_size,
                                          unsigned int *critical);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crl_get_crt_count (gnutls_x509_crl_t crl);

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

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |

#### Returns

number of certificates, a negative error code on failure.

### gnutls_x509_crl_get_crt_serial ()

    int
    gnutls_x509_crl_get_crt_serial (gnutls_x509_crl_t crl,
                                    int indx,
                                    unsigned char *serial,
                                    size_t *serial_size,
                                    time_t *t);

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

Note that this function will have performance issues in large sequences of revoked certificates. In that case use `gnutls_x509_crl_iter_crt_serial()`.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crl_get_dn_oid ()

    int
    gnutls_x509_crl_get_dn_oid (gnutls_x509_crl_t crl,
                                int indx,
                                void *oid,
                                size_t *sizeof_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.

#### Parameters

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' |

#### 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 ()

    int
    gnutls_x509_crl_get_extension_data (gnutls_x509_crl_t crl,
                                        int indx,
                                        void *data,
                                        size_t *sizeof_data);

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.

#### Parameters

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` |

#### 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 ()

    int
    gnutls_x509_crl_get_extension_info (gnutls_x509_crl_t crl,
                                        int indx,
                                        void *oid,
                                        size_t *sizeof_oid,
                                        unsigned int *critical);

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.

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crl_get_extension_oid (gnutls_x509_crl_t crl,
                                       int indx,
                                       void *oid,
                                       size_t *sizeof_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.

#### Parameters

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` |

#### 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 ()

    int
    gnutls_x509_crl_get_issuer_dn (gnutls_x509_crl_t crl,
                                   char *buf,
                                   size_t *sizeof_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.

#### Parameters

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` |

#### 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 ()

    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);

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.

#### Parameters

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-zero 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` |

#### 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 ()

    time_t
    gnutls_x509_crl_get_next_update (gnutls_x509_crl_t crl);

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.

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |

#### Returns

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

### gnutls_x509_crl_get_number ()

    int
    gnutls_x509_crl_get_number (gnutls_x509_crl_t crl,
                                void *ret,
                                size_t *ret_size,
                                unsigned int *critical);

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

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crl_get_raw_issuer_dn (gnutls_x509_crl_t crl,
                                       gnutls_datum_t *dn);

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

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |
dn | will hold the starting point of the DN |

#### Returns

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

Since: 2.12.0

### gnutls_x509_crl_get_signature ()

    int
    gnutls_x509_crl_get_signature (gnutls_x509_crl_t crl,
                                   char *sig,
                                   size_t *sizeof_sig);

This function will extract the signature field of a CRL.

#### Parameters

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` |

#### Returns

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

### gnutls_x509_crl_get_signature_algorithm ()

    int
    gnutls_x509_crl_get_signature_algorithm
                                   (gnutls_x509_crl_t crl);

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

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |

#### Returns

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

### gnutls_x509_crl_get_this_update ()

    time_t
    gnutls_x509_crl_get_this_update (gnutls_x509_crl_t crl);

This function will return the time this CRL was issued.

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |

#### Returns

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

### gnutls_x509_crl_get_version ()

    int
    gnutls_x509_crl_get_version (gnutls_x509_crl_t crl);

This function will return the version of the specified CRL.

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |

#### Returns

The version number, or a negative error code on error.

### gnutls_x509_crl_import ()

    int
    gnutls_x509_crl_import (gnutls_x509_crl_t crl,
                            const gnutls_datum_t *data,
                            gnutls_x509_crt_fmt_t format);

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".

#### Parameters

crl | The structure to store the parsed CRL. |
data | The DER or PEM encoded CRL. |
format | One of DER or PEM |

#### Returns

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

### gnutls_x509_crl_init ()

    int
    gnutls_x509_crl_init (gnutls_x509_crl_t *crl);

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.

#### Parameters

crl | The structure to be initialized |

#### Returns

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

### gnutls_x509_crl_list_import ()

    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);

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".

#### Parameters

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. |

#### Returns

the number of certificates read or a negative error value.

Since: 3.0

### gnutls_x509_crl_list_import2 ()

    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);

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".

#### Parameters

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. |

#### Returns

the number of certificates read or a negative error value.

Since: 3.0

### gnutls_x509_crl_print ()

    int
    gnutls_x509_crl_print (gnutls_x509_crl_t crl,
                           gnutls_certificate_print_formats_t format,
                           gnutls_datum_t *out);

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

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

#### Parameters

crl | The structure to be printed |
format | Indicate the format to use |
out | Newly allocated datum with null terminated string. |

#### Returns

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

### gnutls_x509_crl_set_authority_key_id ()

    int
    gnutls_x509_crl_set_authority_key_id (gnutls_x509_crl_t crl,
                                          const void *id,
                                          size_t id_size);

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.

#### Parameters

crl | a CRL of type gnutls_x509_crl_t |
id | The key ID |
id_size | Holds the size of the serial field. |

#### Returns

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

Since: 2.8.0

### gnutls_x509_crl_set_crt ()

    int
    gnutls_x509_crl_set_crt (gnutls_x509_crl_t crl,
                             gnutls_x509_crt_t crt,
                             time_t revocation_time);

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

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crl_set_crt_serial ()

    int
    gnutls_x509_crl_set_crt_serial (gnutls_x509_crl_t crl,
                                    const void *serial,
                                    size_t serial_size,
                                    time_t revocation_time);

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

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crl_set_next_update ()

    int
    gnutls_x509_crl_set_next_update (gnutls_x509_crl_t crl,
                                     time_t exp_time);

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

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |
exp_time | The actual time |

#### Returns

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

### gnutls_x509_crl_set_number ()

    int
    gnutls_x509_crl_set_number (gnutls_x509_crl_t crl,
                                const void *nr,
                                size_t nr_size);

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.

#### Parameters

crl | a CRL of type gnutls_x509_crl_t |
nr | The CRL number |
nr_size | Holds the size of the nr field. |

#### Returns

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

Since: 2.8.0

### gnutls_x509_crl_set_this_update ()

    int
    gnutls_x509_crl_set_this_update (gnutls_x509_crl_t crl,
                                     time_t act_time);

This function will set the time this CRL was issued.

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |
act_time | The actual time |

#### Returns

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

### gnutls_x509_crl_set_version ()

    int
    gnutls_x509_crl_set_version (gnutls_x509_crl_t crl,
                                 unsigned int version);

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.

#### Parameters

crl | should contain a gnutls_x509_crl_t structure |
version | holds the version number. For CRLv1 crls must be 1. |

#### Returns

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

### gnutls_x509_crl_sign2 ()

    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);

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.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crl_verify ()

    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);

This function will try to verify the given crl and return its verification status. See `gnutls_x509_crt_list_verify()` for a detailed description of return values. Note that since GnuTLS 3.1.4 this function includes the time checks.

Note that value in `verify` is set only when the return value of this function is success (i.e, failure to trust a CRL a certificate does not imply a negative return value).

#### Parameters

crl | is the crl to be verified |
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. |

#### Returns

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

### gnutls_x509_crq_deinit ()

    void
    gnutls_x509_crq_deinit (gnutls_x509_crq_t crq);

This function will deinitialize a PKCS10 certificate request structure.

#### Parameters

crq | The structure to be initialized |

### gnutls_x509_crq_export ()

    int
    gnutls_x509_crq_export (gnutls_x509_crq_t crq,
                            gnutls_x509_crt_fmt_t format,
                            void *output_data,
                            size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_x509_crq_export2 ()

    int
    gnutls_x509_crq_export2 (gnutls_x509_crq_t crq,
                             gnutls_x509_crt_fmt_t format,
                             gnutls_datum_t *out);

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

The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
format | the format of output params. One of PEM or DER. |
out | will contain a certificate request PEM or DER encoded |

#### Returns

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

Since 3.1.3

### gnutls_x509_crq_get_attribute_by_oid ()

    int
    gnutls_x509_crq_get_attribute_by_oid (gnutls_x509_crq_t crq,
                                          const char *oid,
                                          int indx,
                                          void *buf,
                                          size_t *sizeof_buf);

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

Attributes in a certificate request is an optional set of data appended to the request. Their interpretation depends on the CA policy.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
oid | holds an Object Identifier in null-terminated string |
indx | In case multiple same OIDs exist in the attribute list, this specifies which to get, use (0) to get the first one |
buf | a pointer to a structure to hold the attribute data (may be `NULL`) |

#### Returns

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

### gnutls_x509_crq_get_attribute_data ()

    int
    gnutls_x509_crq_get_attribute_data (gnutls_x509_crq_t crq,
                                        int indx,
                                        void *data,
                                        size_t *sizeof_data);

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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
indx | Specifies which attribute number to get. 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` |

#### 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 ()

    int
    gnutls_x509_crq_get_attribute_info (gnutls_x509_crq_t crq,
                                        int indx,
                                        void *oid,
                                        size_t *sizeof_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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
indx | Specifies which attribute number to get. 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` . |

#### 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 ()

    int
    gnutls_x509_crq_get_basic_constraints (gnutls_x509_crq_t crq,
                                           unsigned int *critical,
                                           unsigned int *ca,
                                           int *pathlen);

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).

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
critical | will be non-zero 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. |

#### 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 ()

    int
    gnutls_x509_crq_get_challenge_password
                                   (gnutls_x509_crq_t crq,
                                    char *pass,
                                    size_t *sizeof_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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
pass | will hold a (0)-terminated password string |

#### Returns

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

### gnutls_x509_crq_get_dn ()

    int
    gnutls_x509_crq_get_dn (gnutls_x509_crq_t crq,
                            char *buf,
                            size_t *sizeof_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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
buf | a pointer to a structure to hold the name (may be `NULL`) |

#### 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_crq_get_dn_by_oid ()

    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);

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()`.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
oid | holds an Object Identifier in a null terminated string |
indx | In case multiple same OIDs exist in the RDN, this specifies which to get. Use (0) to get the first one. |
raw_flag | If non-zero returns the raw DER data of the DN part. |
buf | a pointer to a structure to hold the name (may be `NULL`) |

#### 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_crq_get_dn_oid ()

    int
    gnutls_x509_crq_get_dn_oid (gnutls_x509_crq_t crq,
                                int indx,
                                void *oid,
                                size_t *sizeof_oid);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
indx | Specifies which DN OID to get. 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` |

#### 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 ()

    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);

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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
oid | holds an Object Identifier in a null terminated string |
indx | In case multiple same OIDs exist in the extensions, this specifies which to get. Use (0) to get the first one. |
buf | a pointer to a structure to hold the name (may be null) |
critical | will be non-zero if the extension is marked as critical |

#### 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 ()

    int
    gnutls_x509_crq_get_extension_data (gnutls_x509_crq_t crq,
                                        int indx,
                                        void *data,
                                        size_t *sizeof_data);

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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
indx | Specifies which extension number to get. 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` |

#### 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 ()

    int
    gnutls_x509_crq_get_extension_info (gnutls_x509_crq_t crq,
                                        int indx,
                                        void *oid,
                                        size_t *sizeof_oid,
                                        unsigned int *critical);

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.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
indx | Specifies which extension number to get. 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. |

#### 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 ()

    int
    gnutls_x509_crq_get_key_id (gnutls_x509_crq_t crq,
                                unsigned int flags,
                                unsigned char *output_data,
                                size_t *output_data_size);

This function will return a unique ID that 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.

#### Parameters

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) |

#### 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 ()

    int
    gnutls_x509_crq_get_key_purpose_oid (gnutls_x509_crq_t crq,
                                         int indx,
                                         void *oid,
                                         size_t *sizeof_oid,
                                         unsigned int *critical);

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.

#### Parameters

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`. |

#### 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 ()

    int
    gnutls_x509_crq_get_key_rsa_raw (gnutls_x509_crq_t crq,
                                     gnutls_datum_t *m,
                                     gnutls_datum_t *e);

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.

#### Parameters

crq | Holds the certificate |
m | will hold the modulus |
e | will hold the public exponent |

#### Returns

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

Since: 2.8.0

### gnutls_x509_crq_get_key_usage ()

    int
    gnutls_x509_crq_get_key_usage (gnutls_x509_crq_t crq,
                                   unsigned int *key_usage,
                                   unsigned int *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`.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
key_usage | where the key usage bits will be stored |
critical | will be non-zero if the extension is marked as critical |

#### 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 ()

    int
    gnutls_x509_crq_get_pk_algorithm (gnutls_x509_crq_t crq,
                                      unsigned int *bits);

This function will return the public key algorithm of a PKCS10 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.

#### Parameters

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 |

#### 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 ()

    int
    gnutls_x509_crq_get_private_key_usage_period
                                   (gnutls_x509_crq_t cert,
                                    time_t *activation,
                                    time_t *expiration,
                                    unsigned int *critical);

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

#### Parameters

activation | The activation time |
expiration | The expiration time |
critical | the extension status |

#### 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 ()

    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);

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).

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crq_get_subject_alt_othername_oid
                                   (gnutls_x509_crq_t crq,
                                    unsigned int seq,
                                    void *ret,
                                    size_t *ret_size);

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`.

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crq_get_version (gnutls_x509_crq_t crq);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |

#### Returns

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

### gnutls_x509_crq_import ()

    int
    gnutls_x509_crq_import (gnutls_x509_crq_t crq,
                            const gnutls_datum_t *data,
                            gnutls_x509_crt_fmt_t format);

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".

#### Parameters

crq | The structure to store the parsed certificate request. |
data | The DER or PEM encoded certificate. |
format | One of DER or PEM |

#### Returns

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

### gnutls_x509_crq_init ()

    int
    gnutls_x509_crq_init (gnutls_x509_crq_t *crq);

This function will initialize a PKCS10 certificate request structure.

#### Parameters

crq | The structure to be initialized |

#### Returns

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

### gnutls_x509_crq_print ()

    int
    gnutls_x509_crq_print (gnutls_x509_crq_t crq,
                           gnutls_certificate_print_formats_t format,
                           gnutls_datum_t *out);

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

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

#### Parameters

crq | The structure to be printed |
format | Indicate the format to use |
out | Newly allocated datum with null terminated string. |

#### 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 ()

    int
    gnutls_x509_crq_set_attribute_by_oid (gnutls_x509_crq_t crq,
                                          const char *oid,
                                          void *buf,
                                          size_t sizeof_buf);

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

Attributes in a certificate request is an optional set of data appended to the request. Their interpretation depends on the CA policy.

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
oid | holds an Object Identifier in a null-terminated string |
buf | a pointer to a structure that holds the attribute data |

#### Returns

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

### gnutls_x509_crq_set_basic_constraints ()

    int
    gnutls_x509_crq_set_basic_constraints (gnutls_x509_crq_t crq,
                                           unsigned int ca,
                                           int pathLenConstraint);

This function will set the basicConstraints certificate extension.

#### Parameters

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. |

#### Returns

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

Since: 2.8.0

### gnutls_x509_crq_set_challenge_password ()

    int
    gnutls_x509_crq_set_challenge_password
                                   (gnutls_x509_crq_t crq,
                                    const char *pass);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
pass | holds a (0)-terminated password |

#### Returns

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

### gnutls_x509_crq_set_dn_by_oid ()

    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);

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.

#### Parameters

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` |

#### Returns

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

### gnutls_x509_crq_set_key ()

    int
    gnutls_x509_crq_set_key (gnutls_x509_crq_t crq,
                             gnutls_x509_privkey_t key);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
key | holds a private key |

#### Returns

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

### gnutls_x509_crq_set_key_purpose_oid ()

    int
    gnutls_x509_crq_set_key_purpose_oid (gnutls_x509_crq_t crq,
                                         const void *oid,
                                         unsigned int critical);

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.

#### Parameters

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 |

#### 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 ()

    int
    gnutls_x509_crq_set_key_rsa_raw (gnutls_x509_crq_t crq,
                                     const gnutls_datum_t *m,
                                     const gnutls_datum_t *e);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
m | holds the modulus |
e | holds the public exponent |

#### Returns

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

Since: 2.6.0

### gnutls_x509_crq_set_key_usage ()

    int
    gnutls_x509_crq_set_key_usage (gnutls_x509_crq_t crq,
                                   unsigned int usage);

This function will set the keyUsage certificate extension.

#### Parameters

crq | a certificate request of type gnutls_x509_crq_t |
usage | an ORed sequence of the GNUTLS_KEY_* elements. |

#### 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 ()

    int
    gnutls_x509_crq_set_private_key_usage_period
                                   (gnutls_x509_crq_t crq,
                                    time_t activation,
                                    time_t expiration);

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

#### Parameters

crq | a certificate of type gnutls_x509_crq_t |
activation | The activation time |
expiration | The expiration time |

#### Returns

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

### gnutls_x509_crq_set_subject_alt_name ()

    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);

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

`GNUTLS_SAN_DNSNAME`: as a text string

`GNUTLS_SAN_RFC822NAME`: as a text string

`GNUTLS_SAN_URI`: as a text string

`GNUTLS_SAN_IPADDRESS`: as a binary IP address (4 or 16 bytes)

Other values can be set as binary values with the proper DER encoding.

#### Parameters

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. |

#### Returns

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

Since: 2.8.0

### gnutls_x509_crq_set_version ()

    int
    gnutls_x509_crq_set_version (gnutls_x509_crq_t crq,
                                 unsigned int version);

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

#### Parameters

crq | should contain a gnutls_x509_crq_t structure |
version | holds the version number, for v1 Requests must be 1 |

#### Returns

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

### gnutls_x509_crq_sign2 ()

    int
    gnutls_x509_crq_sign2 (gnutls_x509_crq_t crq,
                           gnutls_x509_privkey_t key,
                           gnutls_digest_algorithm_t dig,
                           unsigned int flags);

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.

#### Parameters

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 |

#### 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 ()

    int
    gnutls_x509_crq_verify (gnutls_x509_crq_t crq,
                            unsigned int flags);

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

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crt_check_hostname (gnutls_x509_crt_t cert,
                                    const char *hostname);

This function will check if the given certificate's subject matches the given hostname. This is a basic implementation of the matching described in RFC6125, and takes into account wildcards, and the DNSName/IPAddress subject alternative name PKIX extension.

IPv4 addresses are accepted by this function in the dotted-decimal format (e.g, ddd.ddd.ddd.ddd), and IPv6 addresses in the hexadecimal x:x:x:x:x:x:x:x format. For them the IPAddress subject alternative name extension is consulted, as well as the DNSNames in case of a non-match. The latter fallback exists due to misconfiguration of many servers which place an IPAddress inside the DNSName extension.

The comparison of dns names may have false-negatives as it is done byte by byte in non-ascii names.

When the flag `GNUTLS_VERIFY_DO_NOT_ALLOW_WILDCARDS` is specified no wildcards are considered. Otherwise they are only considered if the domain name consists of three components or more, and the wildcard starts at the leftmost position.

#### Parameters

cert | should contain an gnutls_x509_crt_t structure |
hostname | A null terminated string that contains a DNS name |

#### Returns

non-zero for a successful match, and zero on failure.

### gnutls_x509_crt_check_issuer ()

    int
    gnutls_x509_crt_check_issuer (gnutls_x509_crt_t cert,
                                  gnutls_x509_crt_t issuer);

This function will check if the given certificate was issued by the given issuer. It checks the DN fields and the authority key identifier and subject key identifier fields match.

If the same certificate is provided at the `cert` and `issuer` fields, it will check whether the certificate is self-signed.

#### Parameters

cert | is the certificate to be checked |
issuer | is the certificate of a possible issuer |

#### Returns

It will return true (1) if the given certificate is issued by the given issuer, and false (0) if not.

### gnutls_x509_crt_check_revocation ()

    int
    gnutls_x509_crt_check_revocation (gnutls_x509_crt_t cert,
                                      const gnutls_x509_crl_t *crl_list,
                                      int crl_list_length);

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

#### Parameters

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 |

#### 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 ()

    int
    gnutls_x509_crt_cpy_crl_dist_points (gnutls_x509_crt_t dst,
                                         gnutls_x509_crt_t src);

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.

#### Parameters

dst | a certificate of type gnutls_x509_crt_t |
src | the certificate where the dist points will be copied from |

#### Returns

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

### gnutls_x509_crt_deinit ()

    void
    gnutls_x509_crt_deinit (gnutls_x509_crt_t cert);

This function will deinitialize a certificate structure.

#### Parameters

cert | The structure to be deinitialized |

### gnutls_x509_crt_export ()

    int
    gnutls_x509_crt_export (gnutls_x509_crt_t cert,
                            gnutls_x509_crt_fmt_t format,
                            void *output_data,
                            size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_x509_crt_export2 ()

    int
    gnutls_x509_crt_export2 (gnutls_x509_crt_t cert,
                             gnutls_x509_crt_fmt_t format,
                             gnutls_datum_t *out);

This function will export the certificate to DER or PEM format. The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

cert | Holds the certificate |
format | the format of output params. One of PEM or DER. |
out | will contain a certificate PEM or DER encoded |

#### Returns

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

Since: 3.1.3

### gnutls_x509_crt_get_activation_time ()

    time_t
    gnutls_x509_crt_get_activation_time (gnutls_x509_crt_t cert);

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

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### Returns

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

### gnutls_x509_crt_get_authority_info_access ()

    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);

Note that a simpler API to access the authority info data is provided by `gnutls_x509_aia_get()` and `gnutls_x509_ext_import_aia()`.

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.

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. In that case `GNUTLS_E_UNKNOWN_ALGORITHM` will be returned, and `seq` should be increased and this function called again.

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. In that case handle as in `GNUTLS_IA_OCSP_URI`.

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.

#### Parameters

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-zero if the extension is marked as critical (may be `NULL`) |

#### 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 ()

    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);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_authority_key_id (gnutls_x509_crt_t cert,
                                          void *id,
                                          size_t *id_size,
                                          unsigned int *critical);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_basic_constraints (gnutls_x509_crt_t cert,
                                           unsigned int *critical,
                                           unsigned int *ca,
                                           int *pathlen);

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).

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
critical | will be non-zero 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. |

#### 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 ()

    int
    gnutls_x509_crt_get_ca_status (gnutls_x509_crt_t cert,
                                   unsigned int *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.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
critical | will be non-zero if the extension is marked as critical |

#### 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_crl_dist_points ()

    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);

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

#### Parameters

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.) |
reason_flags | Revocation reasons. An ORed sequence of flags from `gnutls_x509_crl_reason_flags_t`. |
critical | will be non-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_dn (gnutls_x509_crt_t cert,
                            char *buf,
                            size_t *buf_size);

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.

#### Parameters

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` |

#### 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 ()

    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);

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.

#### Parameters

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-zero 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` |

#### 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. `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE` if there are no data in the current index. On success 0 is returned.

### gnutls_x509_crt_get_dn_oid ()

    int
    gnutls_x509_crt_get_dn_oid (gnutls_x509_crt_t cert,
                                int indx,
                                void *oid,
                                size_t *oid_size);

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.

#### Parameters

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` |

#### 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. `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE` if there are no data in the current index. On success 0 is returned.

### gnutls_x509_crt_get_expiration_time ()

    time_t
    gnutls_x509_crt_get_expiration_time (gnutls_x509_crt_t cert);

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

The no well defined expiration time can be checked against with the `GNUTLS_X509_NO_WELL_DEFINED_EXPIRATION` macro.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### Returns

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

### gnutls_x509_crt_get_extension_by_oid ()

    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);

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.

#### Parameters

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-zero if the extension is marked as critical |

#### 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 ()

    int
    gnutls_x509_crt_get_extension_data (gnutls_x509_crt_t cert,
                                        int indx,
                                        void *data,
                                        size_t *sizeof_data);

This function will return the requested extension data in the certificate. The extension data will be stored 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.

#### Parameters

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 `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_x509_crt_get_extension_info ()

    int
    gnutls_x509_crt_get_extension_info (gnutls_x509_crt_t cert,
                                        int indx,
                                        void *oid,
                                        size_t *oid_size,
                                        unsigned int *critical);

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()` 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.

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crt_get_extension_oid (gnutls_x509_crt_t cert,
                                       int indx,
                                       void *oid,
                                       size_t *oid_size);

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.

#### Parameters

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` |

#### 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 ()

    int
    gnutls_x509_crt_get_fingerprint (gnutls_x509_crt_t cert,
                                     gnutls_digest_algorithm_t algo,
                                     void *buf,
                                     size_t *buf_size);

This function will calculate and copy the certificate's fingerprint in the provided buffer. The fingerprint is a hash of the DER-encoded data of the certificate.

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

#### Parameters

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` |

#### 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 ()

    int
    gnutls_x509_crt_get_issuer (gnutls_x509_crt_t cert,
                                gnutls_x509_dn_t *dn);

Return the Certificate's Issuer DN as a `gnutls_x509_dn_t` data type, that can be decoded using `gnutls_x509_dn_get_rdn_ava()`.

Note that `dn` should be treated as constant. Because it points into the `cert` object, you should not use `dn` after `cert` is deallocated.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
dn | output variable with pointer to uint8_t DN |

#### Returns

Returns 0 on success, or an error code.

### gnutls_x509_crt_get_issuer_alt_name ()

    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);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    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);

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).

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_issuer_alt_othername_oid
                                   (gnutls_x509_crt_t cert,
                                    unsigned int seq,
                                    void *ret,
                                    size_t *ret_size);

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`.

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crt_get_issuer_dn (gnutls_x509_crt_t cert,
                                   char *buf,
                                   size_t *buf_size);

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.

#### Parameters

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` |

#### 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 ()

    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);

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.

#### Parameters

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-zero 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` |

#### 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. `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE` if there are no data in the current index. On success 0 is returned.

### gnutls_x509_crt_get_issuer_dn_oid ()

    int
    gnutls_x509_crt_get_issuer_dn_oid (gnutls_x509_crt_t cert,
                                       int indx,
                                       void *oid,
                                       size_t *oid_size);

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.

#### Parameters

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` |

#### 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. `GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE` if there are no data in the current index. On success 0 is returned.

### gnutls_x509_crt_get_issuer_unique_id ()

    int
    gnutls_x509_crt_get_issuer_unique_id (gnutls_x509_crt_t crt,
                                          char *buf,
                                          size_t *buf_size);

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.

#### Parameters

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. |

#### Returns

`GNUTLS_E_SUCCESS` on success, otherwise a negative error code.

Since: 2.12.0

### gnutls_x509_crt_get_key_id ()

    int
    gnutls_x509_crt_get_key_id (gnutls_x509_crt_t crt,
                                unsigned int flags,
                                unsigned char *output_data,
                                size_t *output_data_size);

This function will return a unique ID that 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.

#### Parameters

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) |

#### Returns

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

### gnutls_x509_crt_get_key_purpose_oid ()

    int
    gnutls_x509_crt_get_key_purpose_oid (gnutls_x509_crt_t cert,
                                         int indx,
                                         void *oid,
                                         size_t *oid_size,
                                         unsigned int *critical);

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.

#### Parameters

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 |

#### 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 ()

    int
    gnutls_x509_crt_get_key_usage (gnutls_x509_crt_t cert,
                                   unsigned int *key_usage,
                                   unsigned int *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`.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
key_usage | where the key usage bits will be stored |
critical | will be non-zero if the extension is marked as critical |

#### 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 ()

    int
    gnutls_x509_crt_get_pk_algorithm (gnutls_x509_crt_t cert,
                                      unsigned int *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.

#### Parameters

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 |

#### 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 ()

    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);

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.

#### Parameters

crt | Holds the certificate |
p | will hold the p |
q | will hold the q |
g | will hold the g |
y | will hold the y |

#### Returns

`GNUTLS_E_SUCCESS` on success, otherwise a negative error code.

### gnutls_x509_crt_get_pk_rsa_raw ()

    int
    gnutls_x509_crt_get_pk_rsa_raw (gnutls_x509_crt_t crt,
                                    gnutls_datum_t *m,
                                    gnutls_datum_t *e);

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.

#### Parameters

crt | Holds the certificate |
m | will hold the modulus |
e | will hold the public exponent |

#### Returns

`GNUTLS_E_SUCCESS` on success, otherwise a negative error code.

### gnutls_x509_crt_get_policy ()

    int
    gnutls_x509_crt_get_policy (gnutls_x509_crt_t crt,
                                int indx,
                                struct gnutls_x509_policy_st *policy,
                                unsigned int *critical);

This function will extract the certificate policy (extension 2.5.29.32) specified by the given index.

The policy returned by this function must be deinitialized by using `gnutls_x509_policy_release()`.

#### Parameters

crt | should contain a gnutls_x509_crt_t structure |
indx | This specifies which policy to return. Use (0) to get the first one. |
policy | A pointer to a policy structure. |
critical | will be non-zero if the extension is marked as critical |

#### 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: 3.1.5

### gnutls_x509_crt_get_private_key_usage_period ()

    int
    gnutls_x509_crt_get_private_key_usage_period
                                   (gnutls_x509_crt_t cert,
                                    time_t *activation,
                                    time_t *expiration,
                                    unsigned int *critical);

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.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
activation | The activation time |
expiration | The expiration time |
critical | the extension status |

#### 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 ()

    int
    gnutls_x509_crt_get_proxy (gnutls_x509_crt_t cert,
                               unsigned int *critical,
                               int *pathlen,
                               char **policyLanguage,
                               char **policy,
                               size_t *sizeof_policy);

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).

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
critical | will be non-zero 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 |

#### Returns

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

### gnutls_x509_crt_get_raw_dn ()

    int
    gnutls_x509_crt_get_raw_dn (gnutls_x509_crt_t cert,
                                gnutls_datum_t *start);

This function will return a pointer to the DER encoded DN structure and the length. This points to allocated data that must be free'd using `gnutls_free()`.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### 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 ()

    int
    gnutls_x509_crt_get_raw_issuer_dn (gnutls_x509_crt_t cert,
                                       gnutls_datum_t *start);

This function will return a pointer to the DER encoded DN structure and the length. This points to allocated data that must be free'd using `gnutls_free()`.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### 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 ()

    int
    gnutls_x509_crt_get_serial (gnutls_x509_crt_t cert,
                                void *result,
                                size_t *result_size);

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.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_crt_get_signature ()

    int
    gnutls_x509_crt_get_signature (gnutls_x509_crt_t cert,
                                   char *sig,
                                   size_t *sizeof_sig);

This function will extract the signature field of a certificate.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
sig | a pointer where the signature part will be copied (may be null). |

#### 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 ()

    int
    gnutls_x509_crt_get_signature_algorithm
                                   (gnutls_x509_crt_t cert);

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.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### Returns

a gnutls_sign_algorithm_t value, or a negative error code on error.

### gnutls_x509_crt_get_subject ()

    int
    gnutls_x509_crt_get_subject (gnutls_x509_crt_t cert,
                                 gnutls_x509_dn_t *dn);

Return the Certificate's Subject DN as a `gnutls_x509_dn_t` data type, that can be decoded using `gnutls_x509_dn_get_rdn_ava()`.

Note that `dn` should be treated as constant. Because it points into the `cert` object, you should not use `dn` after `cert` is deallocated.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |
dn | output variable with pointer to uint8_t DN. |

#### Returns

Returns 0 on success, or an error code.

### gnutls_x509_crt_get_subject_alt_name ()

    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);

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.

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    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);

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).

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_subject_alt_othername_oid
                                   (gnutls_x509_crt_t cert,
                                    unsigned int seq,
                                    void *oid,
                                    size_t *oid_size);

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.

#### Parameters

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. |

#### 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 ()

    int
    gnutls_x509_crt_get_subject_key_id (gnutls_x509_crt_t cert,
                                        void *ret,
                                        size_t *ret_size,
                                        unsigned int *critical);

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).

#### Parameters

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-zero if the extension is marked as critical (may be null) |

#### 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 ()

    int
    gnutls_x509_crt_get_subject_unique_id (gnutls_x509_crt_t crt,
                                           char *buf,
                                           size_t *buf_size);

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.

#### Parameters

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. |

#### Returns

`GNUTLS_E_SUCCESS` on success, otherwise a negative error code.

### gnutls_x509_crt_get_version ()

    int
    gnutls_x509_crt_get_version (gnutls_x509_crt_t cert);

This function will return the version of the specified Certificate.

#### Parameters

cert | should contain a gnutls_x509_crt_t structure |

#### Returns

version of certificate, or a negative error code on error.

### gnutls_x509_crt_import ()

    int
    gnutls_x509_crt_import (gnutls_x509_crt_t cert,
                            const gnutls_datum_t *data,
                            gnutls_x509_crt_fmt_t format);

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".

#### Parameters

cert | The structure to store the parsed certificate. |
data | The DER or PEM encoded certificate. |
format | One of DER or PEM |

#### Returns

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

### gnutls_x509_crt_init ()

    int
    gnutls_x509_crt_init (gnutls_x509_crt_t *cert);

This function will initialize an X.509 certificate structure.

#### Parameters

cert | The structure to be initialized |

#### Returns

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

### gnutls_x509_crt_list_import ()

    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);

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".

#### Parameters

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. |

#### Returns

the number of certificates read or a negative error value.

### gnutls_x509_crt_list_import2 ()

    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);

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 allocated and initialized.

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

To deinitialize `certs` , you need to deinitialize each crt structure independently, and use `gnutls_free()` at

#### Parameters

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. |

#### Returns

the number of certificates read or a negative error value.

Since: 3.0

### gnutls_x509_crt_list_verify ()

    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);

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.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_crt_print ()

    int
    gnutls_x509_crt_print (gnutls_x509_crt_t cert,
                           gnutls_certificate_print_formats_t format,
                           gnutls_datum_t *out);

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 deallocated using `gnutls_free()`.

#### Parameters

cert | The structure to be printed |
format | Indicate the format to use |
out | Newly allocated datum with null terminated string. |

#### Returns

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

### gnutls_x509_crt_set_activation_time ()

    int
    gnutls_x509_crt_set_activation_time (gnutls_x509_crt_t cert,
                                         time_t act_time);

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

#### Parameters

cert | a certificate of type gnutls_x509_crt_t |
act_time | The actual time |

#### Returns

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

### gnutls_x509_crt_set_authority_info_access ()

    int
    gnutls_x509_crt_set_authority_info_access
                                   (gnutls_x509_crt_t crt,
                                    int what,
                                    gnutls_datum_t *data);

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.

#### Parameters

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()`. |

#### Returns

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

Since: 3.0

### gnutls_x509_crt_set_authority_key_id ()

    int
    gnutls_x509_crt_set_authority_key_id (gnutls_x509_crt_t cert,
                                          const void *id,
                                          size_t id_size);

This function will set the X.509 certificate's authority key ID extension. Only the keyIdentifier field can be set with this function.

#### Parameters

cert | a certificate of type gnutls_x509_crt_t |
id | The key ID |
id_size | Holds the size of the key ID field. |

#### Returns

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

### gnutls_x509_crt_set_basic_constraints ()

    int
    gnutls_x509_crt_set_basic_constraints (gnutls_x509_crt_t crt,
                                           unsigned int ca,
                                           int pathLenConstraint);

This function will set the basicConstraints certificate extension.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_crt_set_ca_status ()

    int
    gnutls_x509_crt_set_ca_status (gnutls_x509_crt_t crt,
                                   unsigned int ca);

This function will set the basicConstraints certificate extension. Use `gnutls_x509_crt_set_basic_constraints()` if you want to control the pathLenConstraint field too.

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
ca | true(1) or false(0). Depending on the Certificate authority status. |

#### Returns

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

### gnutls_x509_crt_set_crl_dist_points ()

    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);

This function will set the CRL distribution points certificate extension.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crt_set_crl_dist_points2 ()

    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);

This function will set the CRL distribution points certificate extension.

#### Parameters

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 |

#### Returns

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

Since: 2.6.0

### gnutls_x509_crt_set_crq ()

    int
    gnutls_x509_crt_set_crq (gnutls_x509_crt_t crt,
                             gnutls_x509_crq_t crq);

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.

Note that this function will only set the `crq` if it is self signed and the signature is correct. See `gnutls_x509_crq_sign2()`.

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
crq | holds a certificate request |

#### Returns

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

### gnutls_x509_crt_set_crq_extensions ()

    int
    gnutls_x509_crt_set_crq_extensions (gnutls_x509_crt_t crt,
                                        gnutls_x509_crq_t crq);

This function will set extensions from the given request to the certificate.

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
crq | holds a certificate request |

#### 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 ()

    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);

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.

#### Parameters

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` |

#### Returns

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

### gnutls_x509_crt_set_expiration_time ()

    int
    gnutls_x509_crt_set_expiration_time (gnutls_x509_crt_t cert,
                                         time_t exp_time);

This function will set the time this Certificate will expire. Setting an expiration time to (time_t)-1 or to `GNUTLS_X509_NO_WELL_DEFINED_EXPIRATION` will set to the no well-defined expiration date value.

#### Parameters

cert | a certificate of type gnutls_x509_crt_t |
exp_time | The actual time |

#### Returns

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

### gnutls_x509_crt_set_extension_by_oid ()

    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);

This function will set an the extension, by the specified OID, in the certificate. The extension data should be binary data DER encoded.

#### Parameters

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-zero if the extension is to be marked as critical |

#### Returns

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

### gnutls_x509_crt_set_issuer_dn_by_oid ()

    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);

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.

#### Parameters

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` |

#### Returns

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

### gnutls_x509_crt_set_key ()

    int
    gnutls_x509_crt_set_key (gnutls_x509_crt_t crt,
                             gnutls_x509_privkey_t key);

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

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
key | holds a private key |

#### Returns

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

### gnutls_x509_crt_set_key_purpose_oid ()

    int
    gnutls_x509_crt_set_key_purpose_oid (gnutls_x509_crt_t cert,
                                         const void *oid,
                                         unsigned int critical);

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.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crt_set_key_usage ()

    int
    gnutls_x509_crt_set_key_usage (gnutls_x509_crt_t crt,
                                   unsigned int usage);

This function will set the keyUsage certificate extension.

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
usage | an ORed sequence of the GNUTLS_KEY_* elements. |

#### Returns

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

### gnutls_x509_crt_set_pin_function ()

    void
    gnutls_x509_crt_set_pin_function (gnutls_x509_crt_t crt,
                                      gnutls_pin_callback_t fn,
                                      void *userdata);

This function will set a callback function to be used when it is required to access a protected object. This function overrides the global function set using `gnutls_pkcs11_set_pin_function()`.

Note that this callback is currently used only during the import of a PKCS 11 certificate with `gnutls_x509_crt_import_pkcs11_url()`.

#### Parameters

crt | The certificate structure |
fn | the callback |
userdata | data associated with the callback |

Since: 3.1.0

### gnutls_x509_crt_set_policy ()

    int
    gnutls_x509_crt_set_policy (gnutls_x509_crt_t crt,
                                const struct gnutls_x509_policy_st *policy,
                                unsigned int critical);

This function will set the certificate policy extension (2.5.29.32). Multiple calls to this function append a new policy.

Note the maximum text size for the qualifier `GNUTLS_X509_QUALIFIER_NOTICE` is 200 characters. This function will fail with `GNUTLS_E_INVALID_REQUEST` if this is exceeded.

#### Parameters

crt | should contain a gnutls_x509_crt_t structure |
policy | A pointer to a policy structure. |
critical | use non-zero if the extension is marked as critical |

#### Returns

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

Since: 3.1.5

### gnutls_x509_crt_set_private_key_usage_period ()

    int
    gnutls_x509_crt_set_private_key_usage_period
                                   (gnutls_x509_crt_t crt,
                                    time_t activation,
                                    time_t expiration);

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

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
activation | The activation time |
expiration | The expiration time |

#### Returns

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

### gnutls_x509_crt_set_proxy ()

    int
    gnutls_x509_crt_set_proxy (gnutls_x509_crt_t crt,
                               int pathLenConstraint,
                               const char *policyLanguage,
                               const char *policy,
                               size_t sizeof_policy);

This function will set the proxyCertInfo extension.

#### Parameters

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` . |

#### Returns

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

### gnutls_x509_crt_set_proxy_dn ()

    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);

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.

#### Parameters

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` |

#### Returns

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

### gnutls_x509_crt_set_serial ()

    int
    gnutls_x509_crt_set_serial (gnutls_x509_crt_t cert,
                                const void *serial,
                                size_t serial_size);

This function will set the X.509 certificate's serial number. While the serial number is an integer, it is often handled as an opaque field by several CAs. For this reason this function accepts any kind of data as a serial number. To be consistent with the X.509/PKIX specifications the provided `serial` should be a big-endian positive number (i.e. it's leftmost bit should be zero).

#### Parameters

cert | a certificate of type gnutls_x509_crt_t |
serial | The serial number |
serial_size | Holds the size of the serial field. |

#### Returns

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

### gnutls_x509_crt_set_subject_alt_name ()

    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);

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

`GNUTLS_SAN_DNSNAME`: as a text string

`GNUTLS_SAN_RFC822NAME`: as a text string

`GNUTLS_SAN_URI`: as a text string

`GNUTLS_SAN_IPADDRESS`: as a binary IP address (4 or 16 bytes)

Other values can be set as binary values with the proper DER encoding.

#### Parameters

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. |

#### Returns

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

Since: 2.6.0

### gnutls_x509_crt_set_subject_alternative_name ()

    int
    gnutls_x509_crt_set_subject_alternative_name
                                   (gnutls_x509_crt_t crt,
                                    gnutls_x509_subject_alt_name_t type,
                                    const char *data_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()`.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crt_set_subject_key_id ()

    int
    gnutls_x509_crt_set_subject_key_id (gnutls_x509_crt_t cert,
                                        const void *id,
                                        size_t id_size);

This function will set the X.509 certificate's subject key ID extension.

#### Parameters

cert | a certificate of type gnutls_x509_crt_t |
id | The key ID |
id_size | Holds the size of the subject key ID field. |

#### Returns

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

### gnutls_x509_crt_set_version ()

    int
    gnutls_x509_crt_set_version (gnutls_x509_crt_t crt,
                                 unsigned int version);

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()`.

#### Parameters

crt | a certificate of type gnutls_x509_crt_t |
version | holds the version number. For X.509v1 certificates must be 1. |

#### Returns

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

### gnutls_x509_crt_sign ()

    int
    gnutls_x509_crt_sign (gnutls_x509_crt_t crt,
                          gnutls_x509_crt_t issuer,
                          gnutls_x509_privkey_t issuer_key);

This function is the same a `gnutls_x509_crt_sign2()` with no flags, and SHA1 as the hash algorithm.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crt_sign2 ()

    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);

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.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_crt_verify ()

    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);

This function will try to verify the given certificate and return its status. Note that a verification error does not imply a negative return status. In that case the `verify` status is set.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_dn_deinit ()

    void
    gnutls_x509_dn_deinit (gnutls_x509_dn_t dn);

This function deallocates the DN object as returned by `gnutls_x509_dn_import()`.

#### Parameters

dn | a DN uint8_t object pointer. |

Since: 2.4.0

### gnutls_x509_dn_export ()

    int
    gnutls_x509_dn_export (gnutls_x509_dn_t dn,
                           gnutls_x509_crt_fmt_t format,
                           void *output_data,
                           size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_x509_dn_export2 ()

    int
    gnutls_x509_dn_export2 (gnutls_x509_dn_t dn,
                            gnutls_x509_crt_fmt_t format,
                            gnutls_datum_t *out);

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

The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

dn | Holds the uint8_t DN object |
format | the format of output params. One of PEM or DER. |
out | will contain a DN PEM or DER encoded |

#### Returns

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

Since: 3.1.3

### gnutls_x509_dn_get_rdn_ava ()

    int
    gnutls_x509_dn_get_rdn_ava (gnutls_x509_dn_t dn,
                                int irdn,
                                int iava,
                                gnutls_x509_ava_st *ava);

Get pointers to data within the DN. The format of the `ava` structure is shown below.

struct gnutls_x509_ava_st { gnutls_datum_t oid; gnutls_datum_t value; unsigned long value_tag; };

The X.509 distinguished name is a sequence of sequences of strings and this is what the `irdn` and `iava` indexes model.

Note that `ava` will contain pointers into the `dn` structure which in turns points to the original certificate. Thus you should not modify any data or deallocate any of those.

This is a low-level function that requires the caller to do the value conversions when necessary (e.g. from UCS-2).

#### Parameters

dn | a pointer to DN |
irdn | index of RDN |
iava | index of AVA. |
ava | Pointer to structure which will hold output information. |

#### Returns

Returns 0 on success, or an error code.

### gnutls_x509_dn_import ()

    int
    gnutls_x509_dn_import (gnutls_x509_dn_t dn,
                           const gnutls_datum_t *data);

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.

#### Parameters

dn | the structure that will hold the imported DN |
data | should contain a DER encoded RDN sequence |

#### Returns

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

Since: 2.4.0

### gnutls_x509_dn_init ()

    int
    gnutls_x509_dn_init (gnutls_x509_dn_t *dn);

This function initializes a gnutls_x509_dn_t structure.

The object returned must be deallocated using `gnutls_x509_dn_deinit()`.

#### Parameters

dn | the object to be initialized |

#### Returns

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

Since: 2.4.0

### gnutls_x509_dn_oid_known ()

    int
    gnutls_x509_dn_oid_known (const char *oid);

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.

#### Parameters

oid | holds an Object Identifier in a null terminated string |

#### Returns

1 on known OIDs and 0 otherwise.

### gnutls_x509_dn_oid_name ()

    const char *
    gnutls_x509_dn_oid_name (const char *oid,
                             unsigned int flags);

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.

#### Parameters

oid | holds an Object Identifier in a null terminated string |
flags | 0 or GNUTLS_X509_DN_OID_* |

#### Returns

A null terminated string or NULL otherwise.

Since: 3.0

### gnutls_x509_policy_release ()

    void
    gnutls_x509_policy_release (struct gnutls_x509_policy_st *policy);

This function will deinitialize all memory associated with the provided `policy` . The policy is allocated using `gnutls_x509_crt_get_policy()`.

#### Parameters

policy | a certificate policy |

Since: 3.1.5

### gnutls_x509_privkey_cpy ()

    int
    gnutls_x509_privkey_cpy (gnutls_x509_privkey_t dst,
                             gnutls_x509_privkey_t src);

This function will copy a private key from source to destination key. Destination has to be initialized.

#### Parameters

dst | The destination key, which should be initialized. |
src | The source key |

#### Returns

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

### gnutls_x509_privkey_deinit ()

    void
    gnutls_x509_privkey_deinit (gnutls_x509_privkey_t key);

This function will deinitialize a private key structure.

#### Parameters

key | The structure to be deinitialized |

### gnutls_x509_privkey_export ()

    int
    gnutls_x509_privkey_export (gnutls_x509_privkey_t key,
                                gnutls_x509_crt_fmt_t format,
                                void *output_data,
                                size_t *output_data_size);

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".

#### Parameters

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) |

#### Returns

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

### gnutls_x509_privkey_export2 ()

    int
    gnutls_x509_privkey_export2 (gnutls_x509_privkey_t key,
                                 gnutls_x509_crt_fmt_t format,
                                 gnutls_datum_t *out);

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.

The output buffer is allocated using `gnutls_malloc()`.

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

#### Parameters

key | Holds the key |
format | the format of output params. One of PEM or DER. |
out | will contain a private key PEM or DER encoded |

#### Returns

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

Since 3.1.3

### gnutls_x509_privkey_export2_pkcs8 ()

    int
    gnutls_x509_privkey_export2_pkcs8 (gnutls_x509_privkey_t key,
                                       gnutls_x509_crt_fmt_t format,
                                       const char *password,
                                       unsigned int flags,
                                       gnutls_datum_t *out);

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.

The output buffer is allocated using `gnutls_malloc()`.

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.

#### Parameters

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 |
out | will contain a private key PEM or DER encoded |

#### Returns

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

Since 3.1.3

### gnutls_x509_privkey_export_dsa_raw ()

    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);

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.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_privkey_export_ecc_raw ()

    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);

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.

#### Parameters

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 |

#### Returns

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

Since: 3.0

### gnutls_x509_privkey_export_pkcs8 ()

    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);

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.

#### Parameters

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) |

#### Returns

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

### gnutls_x509_privkey_export_rsa_raw ()

    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);

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.

#### Parameters

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 |

#### Returns

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

### gnutls_x509_privkey_export_rsa_raw2 ()

    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);

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.

#### Parameters

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) |

#### Returns

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

Since: 2.12.0

### gnutls_x509_privkey_fix ()

    int
    gnutls_x509_privkey_fix (gnutls_x509_privkey_t key);

This function will recalculate the secondary parameters in a key. In RSA keys, this can be the coefficient and exponent1,2.

#### Parameters

key | Holds the key |

#### Returns

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

### gnutls_x509_privkey_generate ()

    int
    gnutls_x509_privkey_generate (gnutls_x509_privkey_t key,
                                  gnutls_pk_algorithm_t algo,
                                  unsigned int bits,
                                  unsigned int flags);

This function will generate a random private key. Note that this function must be called on an empty private key.

Note that when generating an elliptic curve key, the curve can be substituted in the place of the bits parameter using the `GNUTLS_CURVE_TO_BITS()` macro.

For DSA keys, if the subgroup size needs to be specified check the `GNUTLS_SUBGROUP_TO_BITS()` macro.

Do not set the number of bits directly, use `gnutls_sec_param_to_pk_bits()`.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_privkey_get_key_id ()

    int
    gnutls_x509_privkey_get_key_id (gnutls_x509_privkey_t key,
                                    unsigned int flags,
                                    unsigned char *output_data,
                                    size_t *output_data_size);

This function will return a unique ID that 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.

#### Parameters

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) |

#### Returns

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

### gnutls_x509_privkey_get_pk_algorithm ()

    int
    gnutls_x509_privkey_get_pk_algorithm (gnutls_x509_privkey_t key);

This function will return the public key algorithm of a private key.

#### Parameters

key | should contain a gnutls_x509_privkey_t structure |

#### Returns

a member of the gnutls_pk_algorithm_t enumeration on success, or a negative error code on error.

### gnutls_x509_privkey_get_pk_algorithm2 ()

    int
    gnutls_x509_privkey_get_pk_algorithm2 (gnutls_x509_privkey_t key,
                                           unsigned int *bits);

This function will return the public key algorithm of a private key.

#### Parameters

key | should contain a gnutls_x509_privkey_t structure |
bits | The number of bits in the public key algorithm |

#### Returns

a member of the gnutls_pk_algorithm_t enumeration on success, or a negative error code on error.

### gnutls_x509_privkey_import ()

    int
    gnutls_x509_privkey_import (gnutls_x509_privkey_t key,
                                const gnutls_datum_t *data,
                                gnutls_x509_crt_fmt_t format);

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 that contains "PRIVATE KEY". Note that this function falls back to PKCS #8 decoding without password, if the default format fails to import.

#### Parameters

key | The structure to store the parsed key |
data | The DER or PEM encoded certificate. |
format | One of DER or PEM |

#### Returns

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

### gnutls_x509_privkey_import2 ()

    int
    gnutls_x509_privkey_import2 (gnutls_x509_privkey_t key,
                                 const gnutls_datum_t *data,
                                 gnutls_x509_crt_fmt_t format,
                                 const char *password,
                                 unsigned int flags);

This function will import the given DER or PEM encoded key, to the native gnutls_x509_privkey_t format, irrespective of the input format. The input format is auto-detected.

The supported formats are basic unencrypted key, PKCS8, PKCS12, and the openssl format.

If the provided key is encrypted but no password was given, then `GNUTLS_E_DECRYPTION_FAILED` is returned.

#### Parameters

key | The structure to store the parsed key |
data | The DER or PEM encoded key. |
format | One of DER or PEM |
password | A password (optional) |
flags | an ORed sequence of gnutls_pkcs_encrypt_flags_t |

#### Returns

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

### gnutls_x509_privkey_import_dsa_raw ()

    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);

This function will convert the given DSA raw parameters to the native gnutls_x509_privkey_t format. The output will be stored in `key` .

#### Parameters

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 |

#### Returns

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

### gnutls_x509_privkey_import_ecc_raw ()

    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);

This function will convert the given elliptic curve parameters to the native gnutls_x509_privkey_t format. The output will be stored in `key` .

#### Parameters

key | The structure to store the parsed key |
curve | holds the curve |
x | holds the x |
y | holds the y |
k | holds the k |

#### Returns

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

Since: 3.0

### gnutls_x509_privkey_import_openssl ()

    int
    gnutls_x509_privkey_import_openssl (gnutls_x509_privkey_t key,
                                        const gnutls_datum_t *data,
                                        const char *password);

This function will convert the given PEM encrypted to the native gnutls_x509_privkey_t format. The output will be stored in `key` .

The `password` should be in ASCII. If the password is not provided or wrong then `GNUTLS_E_DECRYPTION_FAILED` will be returned.

If the Certificate is PEM encoded it should have a header of "PRIVATE KEY" and the "DEK-Info" header.

#### Parameters

key | The structure to store the parsed key |
data | The DER or PEM encoded key. |
password | the password to decrypt the key (if it is encrypted). |

#### Returns

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

### gnutls_x509_privkey_import_pkcs8 ()

    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);

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.

If the `GNUTLS_PKCS_PLAIN` flag is specified and the supplied data are encrypted then `GNUTLS_E_DECRYPTION_FAILED` is returned.

#### Parameters

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. |

#### Returns

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

### gnutls_x509_privkey_import_rsa_raw ()

    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);

This function will convert the given RSA raw parameters to the native gnutls_x509_privkey_t format. The output will be stored in `key` .

#### Parameters

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 |

#### Returns

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

### gnutls_x509_privkey_import_rsa_raw2 ()

    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);

This function will convert the given RSA raw parameters to the native gnutls_x509_privkey_t format. The output will be stored in `key` .

#### Parameters

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 (optional) |
e1 | holds e1 = d mod (p-1) (optional) |
e2 | holds e2 = d mod (q-1) (optional) |

#### Returns

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

### gnutls_x509_privkey_init ()

    int
    gnutls_x509_privkey_init (gnutls_x509_privkey_t *key);

This function will initialize an private key structure.

#### Parameters

key | The structure to be initialized |

#### Returns

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

### gnutls_x509_privkey_sec_param ()

    gnutls_sec_param_t
    gnutls_x509_privkey_sec_param (gnutls_x509_privkey_t key);

This function will return the security parameter appropriate with this private key.

#### Parameters

key | a key structure |

#### 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 ()

    int
    gnutls_x509_privkey_verify_params (gnutls_x509_privkey_t key);

This function will verify the private key parameters.

#### Parameters

key | should contain a gnutls_x509_privkey_t structure |

#### Returns

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

### gnutls_x509_rdn_get ()

    int
    gnutls_x509_rdn_get (const gnutls_datum_t *idn,
                         char *buf,
                         size_t *sizeof_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.

#### Parameters

idn | should contain a DER encoded RDN sequence |
buf | a pointer to a structure to hold the peer's name |

#### Returns

On success, `GNUTLS_E_SUCCESS` (0) is returned, or `GNUTLS_E_SHORT_MEMORY_BUFFER` is returned and *`buf_size` is updated if the provided buffer is not long enough, otherwise a negative error value.

### gnutls_x509_rdn_get_by_oid ()

    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);

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.

#### Parameters

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-zero then the raw DER data are returned. |
buf | a pointer to a structure to hold the peer's name |

#### Returns

On success, `GNUTLS_E_SUCCESS` (0) is returned, or `GNUTLS_E_SHORT_MEMORY_BUFFER` is returned and *`buf_size` is updated if the provided buffer is not long enough, otherwise a negative error value.

### gnutls_x509_rdn_get_oid ()

    int
    gnutls_x509_rdn_get_oid (const gnutls_datum_t *idn,
                             int indx,
                             void *buf,
                             size_t *sizeof_buf);

This function will return the specified Object identifier, of the RDN sequence.

#### Parameters

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 |

#### Returns

On success, `GNUTLS_E_SUCCESS` (0) is returned, or `GNUTLS_E_SHORT_MEMORY_BUFFER` is returned and *`buf_size` 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 ()

    int
    gnutls_x509_trust_list_add_cas (gnutls_x509_trust_list_t list,
                                    const gnutls_x509_crt_t *clist,
                                    unsigned  clist_size,
                                    unsigned int flags);

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.

If the flag `GNUTLS_TL_NO_DUPLICATES` is specified, then the provided `clist` entries that are duplicates will not be added to the list and will be deinitialized.

#### Parameters

list | The structure of the list |
clist | A list of CAs |
clist_size | The length of the CA list |
flags | should be 0 or an or'ed sequence of `GNUTLS_TL` options. |

#### Returns

The number of added elements is returned.

Since: 3.0.0

### gnutls_x509_trust_list_add_crls ()

    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);

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. If the flag `GNUTLS_TL_NO_DUPLICATES` is given, then any provided CRLs that are a duplicate, will be deinitialized and not added to the list (that assumes that `gnutls_x509_trust_list_deinit()` will be called with all=1).

#### Parameters

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 |

#### Returns

The number of added elements is returned.

Since: 3.0

### gnutls_x509_trust_list_add_named_crt ()

    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);

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.

#### Parameters

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. |

#### Returns

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

Since: 3.0.0

### gnutls_x509_trust_list_add_system_trust ()

    int
    gnutls_x509_trust_list_add_system_trust
                                   (gnutls_x509_trust_list_t list,
                                    unsigned int tl_flags,
                                    unsigned int tl_vflags);

This function adds the system's default trusted certificate authorities to the trusted list. Note that on unsupported systems this function returns `GNUTLS_E_UNIMPLEMENTED_FEATURE`.

This function implies the flag `GNUTLS_TL_NO_DUPLICATES`.

#### Parameters

list | The structure of the list |
tl_flags | GNUTLS_TL_* |
tl_vflags | gnutls_certificate_verify_flags if flags specifies GNUTLS_TL_VERIFY_CRL |

#### Returns

The number of added elements or a negative error code on error.

Since: 3.1

### gnutls_x509_trust_list_add_trust_file ()

    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);

This function will add the given certificate authorities to the trusted list. PKCS 11 URLs are also accepted, instead of files, by this function. A PKCS 11 URL implies a trust database (a specially marked module in p11-kit); the URL "pkcs11:" implies all trust databases in the system. Only a single URL specifying trust databases can be set; they cannot be stacked with multiple calls.

#### Parameters

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 |

#### Returns

The number of added elements is returned.

Since: 3.1

### gnutls_x509_trust_list_add_trust_mem ()

    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);

This function will add the given certificate authorities to the trusted list.

#### Parameters

list | The structure of the list |
cas | A buffer containing a list of CAs (optional) |
crls | A buffer 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 |

#### Returns

The number of added elements is returned.

Since: 3.1

### gnutls_x509_trust_list_deinit ()

    void
    gnutls_x509_trust_list_deinit (gnutls_x509_trust_list_t list,
                                   unsigned int all);

This function will deinitialize a trust list. Note that the `all` flag should be typically non-zero unless you have specified your certificates using `gnutls_x509_trust_list_add_cas()` and you want to prevent them from being deinitialized by this function.

#### Parameters

list | The structure to be deinitialized |
all | if non-zero it will deinitialize all the certificates and CRLs contained in the structure. |

Since: 3.0.0

### gnutls_x509_trust_list_get_issuer ()

    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);

This function will find the issuer of the given certificate. If the flag `GNUTLS_TL_GET_COPY` is specified a copy of the issuer will be returned which must be freed using `gnutls_x509_crt_deinit()`. Note that the flag `GNUTLS_TL_GET_COPY` is required for this function to work with PKCS 11 trust lists in a thread-safe way.

#### Parameters

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 zero or `GNUTLS_TL_GET_COPY` |

#### Returns

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

Since: 3.0

### gnutls_x509_trust_list_init ()

    int
    gnutls_x509_trust_list_init (gnutls_x509_trust_list_t *list,
                                 unsigned int size);

This function will initialize an X.509 trust list structure.

#### Parameters

list | The structure to be initialized |
size | The size of the internal hash table. Use (0) for default size. |

#### Returns

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

Since: 3.0.0

### gnutls_x509_trust_list_verify_crt ()

    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);

This function will try to verify the given certificate and return its status. The `verify` parameter will hold an OR'ed sequence of `gnutls_certificate_status_t` flags.

Additionally a certificate verification profile can be specified from the ones in `gnutls_certificate_verification_profiles_t` by ORing the result of `GNUTLS_PROFILE_TO_VFLAGS()` to the verification flags.

#### Parameters

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. |
func | If non-null will be called on each chain element verification with the output. |

#### Returns

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

Since: 3.0

### gnutls_x509_trust_list_verify_named_crt ()

    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);

This function will try to find a certificate that is associated with the provided name --see `gnutls_x509_trust_list_add_named_crt()`. If a match is found the certificate is considered valid. In addition to that this function will also check CRLs. The `voutput` parameter will hold an OR'ed sequence of `gnutls_certificate_status_t` flags.

Additionally a certificate verification profile can be specified from the ones in `gnutls_certificate_verification_profiles_t` by ORing the result of `GNUTLS_PROFILE_TO_VFLAGS()` to the verification flags.

#### Parameters

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. |
func | If non-null will be called on each chain element verification with the output. |

#### Returns

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

Since: 3.0.0

## Types and Values

### GNUTLS_CRL_REASON_SUPERSEEDED

    #define GNUTLS_CRL_REASON_SUPERSEEDED GNUTLS_CRL_REASON_SUPERSEDED,

### GNUTLS_FSAN_APPEND

    #define GNUTLS_FSAN_APPEND 1

### GNUTLS_FSAN_SET

    #define GNUTLS_FSAN_SET 0

### GNUTLS_KP_ANY

    #define GNUTLS_KP_ANY				"2.5.29.37.0"

### GNUTLS_KP_CODE_SIGNING

    #define GNUTLS_KP_CODE_SIGNING			"1.3.6.1.5.5.7.3.3"

### GNUTLS_KP_EMAIL_PROTECTION

    #define GNUTLS_KP_EMAIL_PROTECTION		"1.3.6.1.5.5.7.3.4"

### GNUTLS_KP_IPSEC_IKE

    #define GNUTLS_KP_IPSEC_IKE			"1.3.6.1.5.5.7.3.17"

### GNUTLS_KP_MS_SMART_CARD_LOGON

    #define GNUTLS_KP_MS_SMART_CARD_LOGON		"1.3.6.1.4.1.311.20.2.2"

### GNUTLS_KP_OCSP_SIGNING

    #define GNUTLS_KP_OCSP_SIGNING			"1.3.6.1.5.5.7.3.9"

### GNUTLS_KP_TIME_STAMPING

    #define GNUTLS_KP_TIME_STAMPING			"1.3.6.1.5.5.7.3.8"

### GNUTLS_KP_TLS_WWW_CLIENT

    #define GNUTLS_KP_TLS_WWW_CLIENT                "1.3.6.1.5.5.7.3.2"

### GNUTLS_KP_TLS_WWW_SERVER

    #define GNUTLS_KP_TLS_WWW_SERVER		"1.3.6.1.5.5.7.3.1"

### GNUTLS_MAX_QUALIFIERS

    #define GNUTLS_MAX_QUALIFIERS 8

### GNUTLS_OID_AD_CAISSUERS

    #define GNUTLS_OID_AD_CAISSUERS			"1.3.6.1.5.5.7.48.2"

### GNUTLS_OID_AD_OCSP

    #define GNUTLS_OID_AD_OCSP			"1.3.6.1.5.5.7.48.1"

### GNUTLS_OID_AIA

    #define GNUTLS_OID_AIA				"1.3.6.1.5.5.7.1.1"

### GNUTLS_OID_LDAP_DC

    #define GNUTLS_OID_LDAP_DC			"0.9.2342.19200300.100.1.25"

### GNUTLS_OID_LDAP_UID

    #define GNUTLS_OID_LDAP_UID			"0.9.2342.19200300.100.1.1"

### GNUTLS_OID_PKCS9_EMAIL

    #define GNUTLS_OID_PKCS9_EMAIL			"1.2.840.113549.1.9.1"

### GNUTLS_OID_PKIX_COUNTRY_OF_CITIZENSHIP

    #define GNUTLS_OID_PKIX_COUNTRY_OF_CITIZENSHIP "1.3.6.1.5.5.7.9.4"

### GNUTLS_OID_PKIX_COUNTRY_OF_RESIDENCE

    #define GNUTLS_OID_PKIX_COUNTRY_OF_RESIDENCE "1.3.6.1.5.5.7.9.5"

### GNUTLS_OID_PKIX_DATE_OF_BIRTH

    #define GNUTLS_OID_PKIX_DATE_OF_BIRTH		"1.3.6.1.5.5.7.9.1"

### GNUTLS_OID_PKIX_GENDER

    #define GNUTLS_OID_PKIX_GENDER			"1.3.6.1.5.5.7.9.3"

### GNUTLS_OID_PKIX_PLACE_OF_BIRTH

    #define GNUTLS_OID_PKIX_PLACE_OF_BIRTH		"1.3.6.1.5.5.7.9.2"

### GNUTLS_OID_X520_COMMON_NAME

    #define GNUTLS_OID_X520_COMMON_NAME		"2.5.4.3"

### GNUTLS_OID_X520_COUNTRY_NAME

    #define GNUTLS_OID_X520_COUNTRY_NAME		"2.5.4.6"

### GNUTLS_OID_X520_DN_QUALIFIER

    #define GNUTLS_OID_X520_DN_QUALIFIER		"2.5.4.46"

### GNUTLS_OID_X520_GENERATION_QUALIFIER

    #define GNUTLS_OID_X520_GENERATION_QUALIFIER "2.5.4.44"

### GNUTLS_OID_X520_GIVEN_NAME

    #define GNUTLS_OID_X520_GIVEN_NAME		"2.5.4.42"

### GNUTLS_OID_X520_INITIALS

    #define GNUTLS_OID_X520_INITIALS		"2.5.4.43"

### GNUTLS_OID_X520_LOCALITY_NAME

    #define GNUTLS_OID_X520_LOCALITY_NAME		"2.5.4.7"

### GNUTLS_OID_X520_NAME

    #define GNUTLS_OID_X520_NAME                    "2.5.4.41"

### GNUTLS_OID_X520_ORGANIZATIONAL_UNIT_NAME

    #define GNUTLS_OID_X520_ORGANIZATIONAL_UNIT_NAME "2.5.4.11"

### GNUTLS_OID_X520_ORGANIZATION_NAME

    #define GNUTLS_OID_X520_ORGANIZATION_NAME "2.5.4.10"

### GNUTLS_OID_X520_POSTALCODE

    #define GNUTLS_OID_X520_POSTALCODE              "2.5.4.17"

### GNUTLS_OID_X520_PSEUDONYM

    #define GNUTLS_OID_X520_PSEUDONYM		"2.5.4.65"

### GNUTLS_OID_X520_STATE_OR_PROVINCE_NAME

    #define GNUTLS_OID_X520_STATE_OR_PROVINCE_NAME "2.5.4.8"

### GNUTLS_OID_X520_SURNAME

    #define GNUTLS_OID_X520_SURNAME			"2.5.4.4"

### GNUTLS_OID_X520_TITLE

    #define GNUTLS_OID_X520_TITLE			"2.5.4.12"

### GNUTLS_PKCS8_PLAIN

    #define GNUTLS_PKCS8_PLAIN GNUTLS_PKCS_PLAIN

### GNUTLS_PKCS8_USE_PKCS12_3DES

    #define GNUTLS_PKCS8_USE_PKCS12_3DES GNUTLS_PKCS_PKCS12_3DES

### GNUTLS_PKCS8_USE_PKCS12_ARCFOUR

    #define GNUTLS_PKCS8_USE_PKCS12_ARCFOUR GNUTLS_PKCS_PKCS12_ARCFOUR

### GNUTLS_PKCS8_USE_PKCS12_RC2_40

    #define GNUTLS_PKCS8_USE_PKCS12_RC2_40 GNUTLS_PKCS_PKCS12_RC2_40

### GNUTLS_TL_VERIFY_CRL

    #define GNUTLS_TL_VERIFY_CRL 1

### GNUTLS_X509_DN_OID_RETURN_OID

    #define GNUTLS_X509_DN_OID_RETURN_OID 1

### enum gnutls_certificate_import_flags

Enumeration of different certificate import flags.

#### Members

GNUTLS_X509_CRT_LIST_IMPORT_FAIL_IF_EXCEED | Fail if the certificates in the buffer are more than the space allocated for certificates. The error code will be `GNUTLS_E_SHORT_MEMORY_BUFFER`. |
GNUTLS_X509_CRT_LIST_FAIL_IF_UNSORTED | Fail if the certificates in the buffer are not ordered starting from subject to issuer. The error code will be `GNUTLS_E_CERTIFICATE_LIST_UNSORTED`. |

### enum gnutls_certificate_verify_flags

Enumeration of different certificate verify flags. Additional verification profiles can be set using `GNUTLS_PROFILE_TO_VFLAGS()` and `gnutls_certificate_verification_profiles_t`.

#### Members

GNUTLS_VERIFY_DISABLE_CA_SIGN | If set a signer does not have to be a certificate authority. This flag should normally be disabled, unless you know what this means. |
GNUTLS_VERIFY_DO_NOT_ALLOW_SAME | If a certificate is not signed by anyone trusted but exists in the trusted CA list do not treat it as trusted. |
GNUTLS_VERIFY_ALLOW_ANY_X509_V1_CA_CRT | Allow CA certificates that have version 1 (both root and intermediate). This might be dangerous since those haven't the basicConstraints extension. |
GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD2 | Allow certificates to be signed using the broken MD2 algorithm. |
GNUTLS_VERIFY_ALLOW_SIGN_RSA_MD5 | Allow certificates to be signed using the broken MD5 algorithm. |
GNUTLS_VERIFY_DISABLE_TIME_CHECKS | Disable checking of activation and expiration validity periods of certificate chains. Don't set this unless you understand the security implications. |
GNUTLS_VERIFY_DISABLE_TRUSTED_TIME_CHECKS | If set a signer in the trusted list is never checked for expiration or activation. |
GNUTLS_VERIFY_DO_NOT_ALLOW_X509_V1_CA_CRT | Do not allow trusted CA certificates that have version 1. This option is to be used to deprecate all certificates of version 1. |
GNUTLS_VERIFY_DISABLE_CRL_CHECKS | Disable checking for validity using certificate revocation lists or the available OCSP data. |
GNUTLS_VERIFY_ALLOW_UNSORTED_CHAIN | A certificate chain is tolerated if unsorted (the case with many TLS servers out there). This is the default since GnuTLS 3.1.4. |
GNUTLS_VERIFY_DO_NOT_ALLOW_UNSORTED_CHAIN | Do not tolerate an unsorted certificate chain. |
GNUTLS_VERIFY_DO_NOT_ALLOW_WILDCARDS | When including a hostname check in the verification, do not consider any wildcards. |

### enum gnutls_info_access_what_t

Enumeration of types for the `what` parameter of `gnutls_x509_crt_get_authority_info_access()`.

#### Members

GNUTLS_IA_ACCESSMETHOD_OID | Get accessMethod OID. |
GNUTLS_IA_ACCESSLOCATION_GENERALNAME_TYPE | Get accessLocation name type. |
GNUTLS_IA_URI | Get accessLocation URI value. |
GNUTLS_IA_UNKNOWN |  |
GNUTLS_IA_OCSP_URI | get accessLocation URI value for OCSP. |
GNUTLS_IA_CAISSUERS_URI | get accessLocation URI value for caIssuers. |

### gnutls_pkcs7_int

    typedef struct {
    	ASN1_TYPE pkcs7;
    	unsigned expanded;
    } gnutls_pkcs7_int;

### gnutls_pkcs7_t

    typedef struct gnutls_pkcs7_int *gnutls_pkcs7_t;

### enum gnutls_pkcs_encrypt_flags_t

Enumeration of different PKCS encryption flags.

#### Members

GNUTLS_PKCS_PLAIN | Unencrypted private key. |
GNUTLS_PKCS_PKCS12_3DES | PKCS-12 3DES. |
GNUTLS_PKCS_PKCS12_ARCFOUR | PKCS-12 ARCFOUR. |
GNUTLS_PKCS_PKCS12_RC2_40 | PKCS-12 RC2-40. |
GNUTLS_PKCS_PBES2_3DES | PBES2 3DES. |
GNUTLS_PKCS_PBES2_AES_128 | PBES2 AES-128. |
GNUTLS_PKCS_PBES2_AES_192 | PBES2 AES-192. |
GNUTLS_PKCS_PBES2_AES_256 | PBES2 AES-256. |
GNUTLS_PKCS_NULL_PASSWORD | Some schemas distinguish between an empty and a NULL password. |
GNUTLS_PKCS_PBES2_DES | PBES2 single DES. |

### gnutls_x509_crl_get_certificate

    #define gnutls_x509_crl_get_certificate gnutls_x509_crl_get_crt_serial

### gnutls_x509_crl_get_certificate_count

    #define gnutls_x509_crl_get_certificate_count gnutls_x509_crl_get_crt_count

### enum gnutls_x509_crl_reason_flags_t

Enumeration of types for the CRL revocation reasons.

#### Members

GNUTLS_CRL_REASON_UNSPECIFIED |  |
GNUTLS_CRL_REASON_PRIVILEGE_WITHDRAWN | The privileges were withdrawn from the owner. |
GNUTLS_CRL_REASON_CERTIFICATE_HOLD | The certificate is on hold. |
GNUTLS_CRL_REASON_CESSATION_OF_OPERATION | The end-entity is no longer operating. |
GNUTLS_CRL_REASON_SUPERSEDED | There is a newer certificate of the owner. |
GNUTLS_CRL_REASON_AFFILIATION_CHANGED | The end-entity affiliation has changed. |
GNUTLS_CRL_REASON_CA_COMPROMISE | The CA was compromised. |
GNUTLS_CRL_REASON_KEY_COMPROMISE | The certificate's key was compromised. |
GNUTLS_CRL_REASON_UNUSED | The key was never used. |
GNUTLS_CRL_REASON_AA_COMPROMISE | AA compromised. |

### gnutls_x509_dn_t

    typedef void *gnutls_x509_dn_t;

### enum gnutls_x509_qualifier_t

Enumeration of types for the X.509 qualifiers, of the certificate policy extension.

#### Members

GNUTLS_X509_QUALIFIER_UNKNOWN | Unknown qualifier. |
GNUTLS_X509_QUALIFIER_URI | A URL |
GNUTLS_X509_QUALIFIER_NOTICE |  |

### gnutls_x509_trust_list_t

    typedef struct gnutls_x509_trust_list_st *gnutls_x509_trust_list_t;