SSL_dup, SSL_new, SSL_up_ref - create an SSL structure for a connection

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       <https://www.openssl.org/source/license.html>.

3.5.0                                              2025-06-04                                      SSL_NEW(3SSL)

SSL_new() creates a new SSL structure which is needed to hold the data for a TLS/SSL connection. The new
       structure inherits the settings of the underlying context ctx: connection method, options, verification
       settings, timeout settings. An SSL structure is reference counted. Creating an SSL structure for the
       first time increments the reference count. Freeing it (using SSL_free) decrements it. When the reference
       count drops to zero, any memory or resources allocated to the SSL structure are freed.

       SSL_up_ref() increments the reference count for an existing SSL structure.

       The function SSL_dup() creates and returns a new SSL structure from the same SSL_CTX that was used to
       create s. It additionally duplicates a subset of the settings in s into the new SSL object.

       For SSL_dup() to work, the connection MUST be in its initial state and MUST NOT have yet started the SSL
       handshake.  For connections that are not in their initial state SSL_dup() just increments an internal
       reference count and returns the same handle.  It may be possible to use SSL_clear(3) to recycle an SSL
       handle that is not in its initial state for reuse, but this is best avoided.  Instead, save and restore
       the session, if desired, and construct a fresh handle for each connection.

       The subset of settings in s that are duplicated are:

       any session data if configured (including the session_id_context)
       any tmp_dh settings set via SSL_set_tmp_dh(3), SSL_set_tmp_dh_callback(3), or SSL_set_dh_auto(3)
       any configured certificates, private keys or certificate chains
       any configured signature algorithms, or client signature algorithms
       any DANE settings
       any Options set via SSL_set_options(3)
       any Mode set via SSL_set_mode(3)
       any minimum or maximum protocol settings set via SSL_set_min_proto_version(3) or
       SSL_set_max_proto_version(3) (Note: Only from OpenSSL 1.1.1h and above)
       any verify mode, callback or depth set via SSL_set_verify(3) or SSL_set_verify_depth(3) or any configured
       X509 verification parameters
       any msg callback or info callback set via SSL_set_msg_callback(3) or SSL_set_info_callback(3)
       any default password callback set via SSL_set_default_passwd_cb(3)
       any session id generation callback set via SSL_set_generate_session_id(3)
       any configured Cipher List
       initial accept (server) or connect (client) state
       the max cert list value set via SSL_set_max_cert_list(3)
       the read_ahead value set via SSL_set_read_ahead(3)
       application specific data set via SSL_set_ex_data(3)
       any CA list or client CA list set via SSL_set0_CA_list(3), SSL_set0_client_CA_list() or similar functions
       any security level settings or callbacks
       any configured serverinfo data
       any configured PSK identity hint
       any configured custom extensions
       any client certificate types configured via SSL_set1_client_certificate_types

       SSL_dup() is not supported on QUIC SSL objects and returns NULL if called on such an object.

       SSL_dup, SSL_new, SSL_up_ref - create an SSL structure for a connection

       The following return values can occur:

       NULL
           The creation of a new SSL structure failed. Check the error stack to find out the reason.

       Pointer to an SSL structure
           The return value points to an allocated SSL structure.

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

SSL_free(3), SSL_clear(3), SSL_CTX_set_options(3), SSL_get_SSL_CTX(3), ssl(7)

        #include <openssl/ssl.h>

        SSL *SSL_dup(SSL *s);
        SSL *SSL_new(SSL_CTX *ctx);
        int SSL_up_ref(SSL *s);