gnutls_rehandshake(3) — Linux manual page


gnutls_rehandshake(3)            gnutls            gnutls_rehandshake(3)

NAME         top

       gnutls_rehandshake - API function

SYNOPSIS         top

       #include <gnutls/gnutls.h>

       int gnutls_rehandshake(gnutls_session_t session);

ARGUMENTS         top

       gnutls_session_t session
                   is a gnutls_session_t type.

DESCRIPTION         top

       This function can only be called in server side, and instructs a
       TLS 1.2 or earlier client to renegotiate parameters (perform a
       handshake), by sending a hello request message.

       If this function succeeds, the calling application should call
       gnutls_record_recv() until GNUTLS_E_REHANDSHAKE is returned to
       clear any pending data. If the GNUTLS_E_REHANDSHAKE error code is
       not seen, then the handshake request was not followed by the peer
       (the TLS protocol does not require the client to do, and such
       compliance should be handled by the application protocol).

       Once the GNUTLS_E_REHANDSHAKE error code is seen, the calling
       application should proceed to calling gnutls_handshake() to
       negotiate the new parameters.

       If the client does not wish to renegotiate parameters he may
       reply with an alert message, and in that case the return code
       seen by subsequent gnutls_record_recv() will be
       GNUTLS_E_WARNING_ALERT_RECEIVED with the specific alert being
       GNUTLS_A_NO_RENEGOTIATION.  A client may also choose to ignore
       this request.

       Under TLS 1.3 this function is equivalent to
       gnutls_session_key_update() with the GNUTLS_KU_PEER flag. In that
       case subsequent calls to gnutls_record_recv() will not return
       GNUTLS_E_REHANDSHAKE, and calls to gnutls_handshake() in server
       side are a no-op.

       This function always fails with GNUTLS_E_INVALID_REQUEST when
       called in client side.

RETURNS         top

       GNUTLS_E_SUCCESS on success, otherwise a negative error code.

REPORTING BUGS         top

       Report bugs to <>.
       Home page:

COPYRIGHT         top

       Copyright © 2001-2023 Free Software Foundation, Inc., and others.
       Copying and distribution of this file, with or without
       modification, are permitted in any medium without royalty
       provided the copyright notice and this notice are preserved.

SEE ALSO         top

       The full documentation for gnutls is maintained as a Texinfo
       manual.  If the /usr/share/doc/gnutls/ directory does not contain
       the HTML form visit

COLOPHON         top

       This page is part of the GnuTLS (GnuTLS Transport Layer Security
       Library) project.  Information about the project can be found at
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       manual page, send it to  This page was obtained
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gnutls                            3.8.2            gnutls_rehandshake(3)