NAME¶
SSL_clear - reset SSL object to allow another connection
SYNOPSIS¶
#include <openssl/ssl.h>
int SSL_clear(SSL *ssl);
DESCRIPTION¶
Reset
ssl to allow another connection. All settings (method, ciphers,
BIOs) are kept.
NOTES¶
SSL_clear is used to prepare an SSL object for a new connection. While all
settings are kept, a side effect is the handling of the current SSL session.
If a session is still
open, it is considered bad and will be removed
from the session cache, as required by RFC2246. A session is considered open,
if
SSL_shutdown(3) was not called for the connection or at least
SSL_set_shutdown(3) was used to set the SSL_SENT_SHUTDOWN state.
If a session was closed cleanly, the session object will be kept and all
settings corresponding. This explicitly means, that e.g. the special method
used during the session will be kept for the next handshake. So if the session
was a TLSv1 session, a SSL client object will use a TLSv1 client method for
the next handshake and a SSL server object will use a TLSv1 server method,
even if SSLv23_*_methods were chosen on startup. This will might lead to
connection failures (see
SSL_new(3)) for a description of the method's
properties.
WARNINGS¶
SSL_clear() resets the SSL object to allow for another connection. The
reset operation however keeps several settings of the last sessions (some of
these settings were made automatically during the last handshake). It only
makes sense for a new connection with the exact same peer that shares these
settings, and may fail if that peer changes its settings between connections.
Use the sequence
SSL_get_session(3);
SSL_new(3);
SSL_set_session(3);
SSL_free(3) instead to avoid such failures
(or simply
SSL_free(3);
SSL_new(3) if session reuse is not
desired).
RETURN VALUES¶
The following return values can occur:
- 0
- The SSL_clear() operation could not be performed. Check the error
stack to find out the reason.
- 1
- The SSL_clear() operation was successful.
SSL_new(3),
SSL_free(3),
SSL_shutdown(3),
SSL_set_shutdown(3),
SSL_CTX_set_options(3),
ssl(3),
SSL_CTX_set_client_cert_cb(3)