gnutls_dtls_cookie_send — API function
Synopsis
#include <gnutls/dtls.h>
int gnutls_dtls_cookie_send(gnutls_datum_t * key, void * client_data, size_t client_data_size, gnutls_dtls_prestate_st * prestate, gnutls_transport_ptr_t ptr, gnutls_push_func push_func);
Arguments
- gnutls_datum_t * key
is a random key to be used at cookie generation
- void * client_data
contains data identifying the client (i.e. address)
- size_t client_data_size
The size of client's data
- gnutls_dtls_prestate_st * prestate
The previous cookie returned by gnutls_dtls_cookie_verify()
- gnutls_transport_ptr_t ptr
A transport pointer to be used by push_func
- gnutls_push_func push_func
A function that will be used to reply
Description
This function can be used to prevent denial of service attacks to a DTLS server by requiring the client to reply using a cookie sent by this function. That way it can be ensured that a client we allocated resources for (i.e. gnutls_session_t) is the one that the original incoming packet was originated from.
This function must be called at the first incoming packet, prior to allocating any resources and must be succeeded by gnutls_dtls_cookie_verify().
Returns
the number of bytes sent, or a negative error code.
Since
3.0
Reporting Bugs
Report bugs to <bugs@gnutls.org>.
Home page: https://www.gnutls.org
Copyright
Copyright © 2001-2019 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