gnutls_prf(3) — Linux manual pages

Linux manual pages	Section 3: Subroutines

Name

gnutls_prf — API function

Synopsis

#include <gnutls/gnutls.h>

`int gnutls_prf(`	gnutls_session_t `session`,
	size_t `label_size`,
	const char * `label`,
	int `server_random_first`,
	size_t `extra_size`,
	const char * `extra`,
	size_t `outsize`,
	char * `out)`;

ARGUMENTS

gnutls_session_t session: is a gnutls_session_t structure.
size_t label_size: length of the label variable.
const char * label: label used in PRF computation, typically a short string.
int server_random_first: non−0 if server random field should be first in seed
size_t extra_size: length of the extra variable.
const char * extra: optional extra data to seed the PRF with.
size_t outsize: size of pre−allocated output buffer to hold the output.
char * out: pre−allocated buffer to hold the generated data.

DESCRIPTION

Applies the TLS Pseudo−Random−Function (PRF) on the master secret and the provided data, seeded with the client and server random fields, as specified in RFC5705.

The label variable usually contains a string denoting the purpose for the generated data. The server_random_first indicates whether the client random field or the server random field should be first in the seed. Non−0 indicates that the server random field is first, 0 that the client random field is first.

The extra variable can be used to add more data to the seed, after the random variables. It can be used to make sure the generated output is strongly connected to some additional data (e.g., a string used in user authentication).

The output is placed in out , which must be pre−allocated.

RETURNS

GNUTLS_E_SUCCESS on success, or an error code.

REPORTING BUGS

Report bugs to <bug-gnutls@gnu.org>.

General guidelines for reporting bugs: http://www.gnu.org/gethelp/