NAME

       gnutls_handshake_set_hook_function - API function

SYNOPSIS

       #include <gnutls/gnutls.h>

       void  gnutls_handshake_set_hook_function(gnutls_session_t session, unsigned int htype, int
       post, gnutls_handshake_hook_func func);

ARGUMENTS

       gnutls_session_t session
                   is a gnutls_session_t type

       unsigned int htype
                   the gnutls_handshake_description_t of the message to hook at

       int post    GNUTLS_HOOK_* depending on when the hook function should be called

       gnutls_handshake_hook_func func
                   is the function to be called

DESCRIPTION

       This function will set a callback to be called after or  before  the  specified  handshake
       message    has    been    received   or   generated.   This   is   a   generalization   of
       gnutls_handshake_set_post_client_hello_function().

       To call the hook function prior to the message being sent/generated use GNUTLS_HOOK_PRE as
       post parameter, GNUTLS_HOOK_POST to call after, and GNUTLS_HOOK_BOTH for both cases.

       This callback must return 0 on success or a gnutls error code to terminate the handshake.

       Note to hook at all handshake messages use an  htype of GNUTLS_HANDSHAKE_ANY.

WARNING

       You  should  not use this function to terminate the handshake based on client input unless
       you know what you are doing. Before the handshake is finished there is no way to  know  if
       there is a man-in-the-middle attack being performed.

REPORTING BUGS

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

COPYRIGHT

       Copyright © 2001-2021 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

       http://www.gnutls.org/manual/