SSL_get_certificate, SSL_get_privatekey - retrieve TLS/SSL certificate and private key

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       Licensed under the Apache License 2.0 (the "License").  You may not use this file  except  in  compliance
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       <https://www.openssl.org/source/license.html>.

3.5.0                                              2025-06-04                          SSL_GET_CERTIFICATE(3SSL)

SSL_get_certificate() returns a pointer to an X509 object representing a certificate used as the local
       peer's identity.

       Multiple certificates can be configured; for example, a server might have both RSA and ECDSA
       certificates. The certificate which is returned by SSL_get_certificate() is determined as follows:

       •   If  it  is  called  before  certificate  selection  has  occurred, it returns the most recently added
           certificate, or NULL if no certificate has been added.

       •   After certificate selection has occurred, it returns the certificate which was  selected  during  the
           handshake,  or  NULL  if  no  certificate  was  selected  (for  example,  on a client where no client
           certificate is in use).

       Certificate selection occurs during the handshake; therefore, the value returned by SSL_get_certificate()
       during any callback made during the handshake process will depend on whether that callback is made before
       or after certificate selection occurs.

       A   specific   use   for   SSL_get_certificate()   is   inside   a   callback   set   via   a   call   to
       SSL_CTX_set_tlsext_status_cb(3).  This  callback occurs after certificate selection, where it can be used
       to examine a server's chosen certificate, for example for the purpose of identifying a certificate's OCSP
       responder URL so that an OCSP response can be obtained.

       SSL_get_privatekey() returns a pointer to the EVP_PKEY object corresponding to the  certificate  returned
       by SSL_get_certificate(), if any.

       SSL_get_certificate, SSL_get_privatekey - retrieve TLS/SSL certificate and private key

       These  functions  return  pointers  to  their respective objects, or NULL if no such object is available.
       Returned objects are owned by the SSL object and should not be freed by users of these functions.

ssl(7), SSL_CTX_set_tlsext_status_cb(3)

        #include <openssl/ssl.h>

        X509 *SSL_get_certificate(const SSL *s);
        EVP_PKEY *SSL_get_privatekey(const SSL *s);