| =pod |
| |
| =head1 NAME |
| |
| SSL_dup, SSL_new, SSL_up_ref - create an SSL structure for a connection |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/ssl.h> |
| |
| SSL *SSL_dup(SSL *s); |
| SSL *SSL_new(SSL_CTX *ctx); |
| int SSL_up_ref(SSL *s); |
| |
| =head1 DESCRIPTION |
| |
| SSL_new() creates a new B<SSL> structure which is needed to hold the |
| data for a TLS/SSL connection. The new structure inherits the settings |
| of the underlying context B<ctx>: connection method, |
| options, verification settings, timeout settings. An B<SSL> structure is |
| reference counted. Creating an B<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 B<SSL> |
| structure are freed. |
| |
| SSL_up_ref() increments the reference count for an |
| existing B<SSL> structure. |
| |
| SSL_dup() duplicates an existing B<SSL> structure into a new allocated one |
| or just increments the reference count if the connection is active. All |
| settings are inherited from the original B<SSL> structure. Dynamic data (i.e. |
| existing connection details) are not copied, the new B<SSL> is set into an |
| initial accept (server) or connect (client) state. |
| |
| SSL_dup() allows applications to configure an SSL handle for use in multiple |
| SSL connections, and then duplicate it prior to initiating each connection |
| with the duplicated handle. Use of SSL_dup() avoids the need to repeat |
| the configuration of the handles for each connection. |
| |
| For SSL_dup() to work, the connection MUST be in its initial state and |
| MUST NOT have not yet have started the SSL handshake. For connections |
| that are not in their initial state SSL_dup() just increments an internal |
| reference count and returns the I<same> handle. It may be possible to |
| use L<SSL_clear(3)> to recycle an SSL handle that is not in its initial |
| state for re-use, but this is best avoided. Instead, save and restore |
| the session, if desired, and construct a fresh handle for each connection. |
| |
| =head1 RETURN VALUES |
| |
| The following return values can occur: |
| |
| =over 4 |
| |
| =item NULL |
| |
| The creation of a new SSL structure failed. Check the error stack to |
| find out the reason. |
| |
| =item 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. |
| |
| =back |
| |
| =head1 SEE ALSO |
| |
| L<SSL_free(3)>, L<SSL_clear(3)>, |
| L<SSL_CTX_set_options(3)>, |
| L<SSL_get_SSL_CTX(3)>, |
| L<ssl(7)> |
| |
| =head1 COPYRIGHT |
| |
| Copyright 2000-2017 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 |
| L<https://www.openssl.org/source/license.html>. |
| |
| =cut |
