Name

gnutls_dtls_cookie_send — API function

Synopsis

#include <gnutls/gnutls.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.

RETURNS

the number of bytes sent, or a negative error code.

REPORTING BUGS

Report bugs to <bug-gnutls@gnu.org>. GnuTLS home page: http://www.gnu.org/software/gnutls/ General help using GNU software: http://www.gnu.org/gethelp/

SEE ALSO

The full documentation for gnutls is maintained as a Texinfo manual. If the info and gnutls programs are properly installed at your site, the command

info gnutls

should give you access to the complete manual.

COPYRIGHT

Copyright © 2008 Free Software Foundation.

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.