NAME

       OCSP_cert_to_id, OCSP_cert_id_new, OCSP_CERTID_free, OCSP_id_issuer_cmp, OCSP_id_cmp, OCSP_id_get0_info -
       OCSP certificate ID utility functions

SYNOPSIS

        #include <openssl/ocsp.h>

        OCSP_CERTID *OCSP_cert_to_id(const EVP_MD *dgst,
                                     X509 *subject, X509 *issuer);

        OCSP_CERTID *OCSP_cert_id_new(const EVP_MD *dgst,
                                      X509_NAME *issuerName,
                                      ASN1_BIT_STRING *issuerKey,
                                      ASN1_INTEGER *serialNumber);

        void OCSP_CERTID_free(OCSP_CERTID *id);

        int OCSP_id_issuer_cmp(const OCSP_CERTID *a, const OCSP_CERTID *b);
        int OCSP_id_cmp(const OCSP_CERTID *a, const OCSP_CERTID *b);

        int OCSP_id_get0_info(ASN1_OCTET_STRING **piNameHash, ASN1_OBJECT **pmd,
                              ASN1_OCTET_STRING **pikeyHash,
                              ASN1_INTEGER **pserial, OCSP_CERTID *cid);

DESCRIPTION

       OCSP_cert_to_id() creates and returns a new OCSP_CERTID structure using message digest dgst for
       certificate subject with issuer issuer. If dgst is NULL then SHA1 is used.

       OCSP_cert_id_new() creates and returns a new OCSP_CERTID using dgst and issuer name issuerName, issuer
       key hash issuerKey and serial number serialNumber.

       OCSP_CERTID_free() frees up id.

       OCSP_id_cmp() compares OCSP_CERTID a and b.

       OCSP_id_issuer_cmp() compares only the issuer name of OCSP_CERTID a and b.

       OCSP_id_get0_info() returns the issuer name hash, hash OID, issuer key hash and serial number contained
       in cid. If any of the values are not required the corresponding parameter can be set to NULL.

RETURN VALUES

       OCSP_cert_to_id() and OCSP_cert_id_new() return either a pointer to a valid OCSP_CERTID structure or NULL
       if an error occurred.

       OCSP_id_cmp() and OCSP_id_issuer_cmp() returns zero for a match and nonzero otherwise.

       OCSP_CERTID_free() does not return a value.

       OCSP_id_get0_info() returns 1 for success and 0 for failure.

NOTES

       OCSP clients will typically only use OCSP_cert_to_id() or OCSP_cert_id_new(): the other functions are
       used by responder applications.

       The values returned by OCSP_id_get0_info() are internal pointers and MUST NOT be freed up by an
       application: they will be freed when the corresponding OCSP_CERTID structure is freed.

SEE ALSO

       crypto(7), OCSP_request_add1_nonce(3), OCSP_REQUEST_new(3), OCSP_resp_find_status(3),
       OCSP_response_status(3), OCSP_sendreq_new(3)

COPYRIGHT

       Copyright 2015-2016 The OpenSSL Project Authors. All Rights Reserved.

       Licensed under the Apache License 2.0 (the "License").  You may not use this file except in compliance
       with the License.  You can obtain a copy in the file LICENSE in the source distribution or at
       <https://www.openssl.org/source/license.html>.

3.0.13                                             2025-09-18                              OCSP_CERT_TO_ID(3SSL)