NAME

       X509_get_pubkey, X509_get0_pubkey, X509_set_pubkey, X509_get_X509_PUBKEY,
       X509_REQ_get_pubkey, X509_REQ_get0_pubkey, X509_REQ_set_pubkey, X509_REQ_get_X509_PUBKEY -
       get or set certificate or certificate request public key

SYNOPSIS

        #include <openssl/x509.h>

        EVP_PKEY *X509_get_pubkey(X509 *x);
        EVP_PKEY *X509_get0_pubkey(const X509 *x);
        int X509_set_pubkey(X509 *x, EVP_PKEY *pkey);
        X509_PUBKEY *X509_get_X509_PUBKEY(const X509 *x);

        EVP_PKEY *X509_REQ_get_pubkey(X509_REQ *req);
        EVP_PKEY *X509_REQ_get0_pubkey(X509_REQ *req);
        int X509_REQ_set_pubkey(X509_REQ *x, EVP_PKEY *pkey);
        X509_PUBKEY *X509_REQ_get_X509_PUBKEY(X509_REQ *x);

DESCRIPTION

       X509_get_pubkey() attempts to decode the public key for certificate x. If successful it
       returns the public key as an EVP_PKEY pointer with its reference count incremented: this
       means the returned key must be freed up after use. X509_get0_pubkey() is similar except it
       does not increment the reference count of the returned EVP_PKEY so it must not be freed up
       after use.

       X509_get_X509_PUBKEY() returns an internal pointer to the X509_PUBKEY structure which
       encodes the certificate of x. The returned value must not be freed up after use.

       X509_set_pubkey() attempts to set the public key for certificate x to pkey. The key pkey
       should be freed up after use.

       X509_REQ_get_pubkey(), X509_REQ_get0_pubkey(), X509_REQ_set_pubkey() and
       X509_REQ_get_X509_PUBKEY() are similar but operate on certificate request req.

NOTES

       The first time a public key is decoded the EVP_PKEY structure is cached in the certificate
       or certificate request itself. Subsequent calls return the cached structure with its
       reference count incremented to improve performance.

RETURN VALUES

       X509_get_pubkey(), X509_get0_pubkey(), X509_get_X509_PUBKEY(), X509_REQ_get_pubkey() and
       X509_REQ_get_X509_PUBKEY() return a public key or NULL if an error occurred.

       X509_set_pubkey() and X509_REQ_set_pubkey() return 1 for success and 0 for failure.

SEE ALSO

       d2i_X509(3), ERR_get_error(3), X509_CRL_get0_by_serial(3), X509_get0_signature(3),
       X509_get_ext_d2i(3), X509_get_extension_flags(3), X509_get_subject_name(3),
       X509_get_version(3), X509_NAME_add_entry_by_txt(3), X509_NAME_ENTRY_get_object(3),
       X509_NAME_get_index_by_NID(3), X509_NAME_print_ex(3), X509_new(3), X509_sign(3),
       X509V3_get_d2i(3), X509_verify_cert(3)

COPYRIGHT

       Copyright 2015-2021 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>.