NAME¶
gnutls_srp_set_server_credentials_function - API function
SYNOPSIS¶
#include <gnutls/gnutls.h>
void
gnutls_srp_set_server_credentials_function(gnutls_srp_server_credentials_t
cred, gnutls_srp_server_credentials_function *
func);
ARGUMENTS¶
- gnutls_srp_server_credentials_t cred
- is a gnutls_srp_server_credentials_t structure.
- gnutls_srp_server_credentials_function * func
- is the callback function
DESCRIPTION¶
This function can be used to set a callback to retrieve the user's SRP
credentials. The callback's function form is:
int (*callback)(gnutls_session_t, const char* username, gnutls_datum_t *salt,
gnutls_datum_t *verifier, gnutls_datum_t *generator, gnutls_datum_t *prime);
username contains the actual username. The
salt ,
verifier
,
generator and
prime must be filled in using the
gnutls_malloc(). For convenience
prime and
generator may
also be one of the static parameters defined in gnutls.h.
Initially, the data field is NULL in every
gnutls_datum_t structure that
the callback has to fill in. When the callback is done GnuTLS deallocates all
of those buffers which are non-NULL, regardless of the return value.
In order to prevent attackers from guessing valid usernames, if a user does not
exist, g and n values should be filled in using a random user's parameters. In
that case the callback must return the special value (1). See
gnutls_srp_set_server_fake_salt_seed too. If this is not required for
your application, return a negative number from the callback to abort the
handshake.
The callback function will only be called once per handshake. The callback
function should return 0 on success, while -1 indicates an error.
REPORTING BUGS¶
Report bugs to <bugs@gnutls.org>.
Home page:
http://www.gnutls.org
COPYRIGHT¶
Copyright © 2001-2014 Free Software Foundation, Inc..
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
- http://www.gnutls.org/manual/