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gnutls_handshake_set_hook_function - Man Page

API function


#include <gnutls/gnutls.h>

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


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 when

GNUTLS_HOOK_* depending on when the hook function should be called

gnutls_handshake_hook_func func

is the function to be called


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 generated or processed use GNUTLS_HOOK_PRE as  when 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.

To hook at all handshake messages use an  htype of GNUTLS_HANDSHAKE_ANY.


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: https://www.gnutls.org

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



3.8.6 gnutls