NAME

       gnutls_rehandshake - API function

SYNOPSIS

       #include <gnutls/gnutls.h>

       int gnutls_rehandshake(gnutls_session_t session);

ARGUMENTS

       gnutls_session_t session
                   is a gnutls_session_t type.

DESCRIPTION

       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

       GNUTLS_E_SUCCESS on success, otherwise a negative error code.

REPORTING BUGS

       Report bugs to <bugs@gnutls.org>.
       Home page: https://www.gnutls.org

COPYRIGHT

       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

       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

       https://www.gnutls.org/manual/