SSL_CTX_set_session_id_conteOpSSL_CTX_set_session_id_context(3)





NAME
       SSL_CTX_set_session_id_context, SSL_set_session_id_con-
       text - set context within which session can be reused
       (server side only)

SYNOPSIS
        #include <openssl/ssl.h>

        int SSL_CTX_set_session_id_context(SSL_CTX *ctx, const unsigned char *sid_ctx,
                                           unsigned int sid_ctx_len);
        int SSL_set_session_id_context(SSL *ssl, const unsigned char *sid_ctx,
                                       unsigned int sid_ctx_len);

DESCRIPTION
       SSL_CTX_set_session_id_context() sets the context
       sid_ctx of length sid_ctx_len within which a session can
       be reused for the ctx object.

       SSL_set_session_id_context() sets the context sid_ctx of
       length sid_ctx_len within which a session can be reused
       for the ssl object.

NOTES
       Sessions are generated within a certain context. When
       exporting/importing sessions with i2d_SSL_SES-
       SION/d2i_SSL_SESSION it would be possible, to re-import
       a session generated from another context (e.g. another
       application), which might lead to malfunctions. There-
       fore each application must set its own session id con-
       text sid_ctx which is used to distinguish the contexts
       and is stored in exported sessions. The sid_ctx can be
       any kind of binary data with a given length, it is
       therefore possible to use e.g. the name of the applica-
       tion and/or the hostname and/or service name ...

       The session id context becomes part of the session. The
       session id context is set by the SSL/TLS server. The
       SSL_CTX_set_session_id_context() and SSL_set_ses-
       sion_id_context() functions are therefore only useful on
       the server side.

       OpenSSL clients will check the session id context
       returned by the server when reusing a session.

       The maximum length of the sid_ctx is limited to
       SSL_MAX_SSL_SESSION_ID_LENGTH.

WARNINGS
       If the session id context is not set on an SSL/TLS
       server, stored sessions will not be reused but a fatal
       error will be flagged and the handshake will fail.

       If a server returns a different session id context to an
       OpenSSL client when reusing a session, an error will be
       flagged and the handshake will fail. OpenSSL servers
       will always return the correct session id context, as an
       OpenSSL server checks the session id context itself
       before reusing a session as described above.

RETURN VALUES
       SSL_CTX_set_session_id_context() and SSL_set_ses-
       sion_id_context() return the following values:

       o   The length sid_ctx_len of the session id context
           sid_ctx exceeded the maximum allowed length of
           SSL_MAX_SSL_SESSION_ID_LENGTH. The error is logged
           to the error stack.

       1   The operation succeeded.

SEE ALSO
       ssl(3)



0.9.7c                     200SSL_CTX_set_session_id_context(3)
