1gnutls_dtls_cookie_send(3)          gnutls          gnutls_dtls_cookie_send(3)
2
3
4

NAME

6       gnutls_dtls_cookie_send - API function
7

SYNOPSIS

9       #include <gnutls/dtls.h>
10
11       int  gnutls_dtls_cookie_send(gnutls_datum_t  * key, void * client_data,
12       size_t   client_data_size,    gnutls_dtls_prestate_st    *    prestate,
13       gnutls_transport_ptr_t ptr, gnutls_push_func push_func);
14

ARGUMENTS

16       gnutls_datum_t * key
17                   is a random key to be used at cookie generation
18
19       void * client_data
20                   contains data identifying the client (i.e. address)
21
22       size_t client_data_size
23                   The size of client's data
24
25       gnutls_dtls_prestate_st * prestate
26                   The previous cookie returned by gnutls_dtls_cookie_verify()
27
28       gnutls_transport_ptr_t ptr
29                   A transport pointer to be used by  push_func
30
31       gnutls_push_func push_func
32                   A function that will be used to reply
33

DESCRIPTION

35       This  function  can  be  used to prevent denial of service attacks to a
36       DTLS server by requiring the client to reply using  a  cookie  sent  by
37       this  function.  That  way it can be ensured that a client we allocated
38       resources for (i.e. gnutls_session_t) is  the  one  that  the  original
39       incoming packet was originated from.
40
41       This  function  must  be  called at the first incoming packet, prior to
42       allocating    any    resources    and    must    be    succeeded     by
43       gnutls_dtls_cookie_verify().
44

RETURNS

46       the number of bytes sent, or a negative error code.
47

SINCE

49       3.0
50

REPORTING BUGS

52       Report bugs to <bugs@gnutls.org>.
53       Home page: https://www.gnutls.org
54
55

57       Copyright © 2001- Free Software Foundation, Inc., and others.
58       Copying  and  distribution  of this file, with or without modification,
59       are permitted in any medium  without  royalty  provided  the  copyright
60       notice and this notice are preserved.
61

SEE ALSO

63       The  full  documentation  for gnutls is maintained as a Texinfo manual.
64       If the /usr/share/doc/gnutls/ directory does not contain the HTML  form
65       visit
66
67       https://www.gnutls.org/manual/
68
69gnutls                              3.6.15          gnutls_dtls_cookie_send(3)
Impressum