/**
* gnutls_srtp_get_keys:
* @session: is a #gnutls_session_t type.
* @key_material: Space to hold the generated key material
* @key_material_size: The maximum size of the key material
* @client_key: The master client write key, pointing inside the key material
* @server_key: The master server write key, pointing inside the key material
* @client_salt: The master client write salt, pointing inside the key material
* @server_salt: The master server write salt, pointing inside the key material
*
* This is a helper function to generate the keying material for SRTP.
* It requires the space of the key material to be pre-allocated (should be at least
* 2x the maximum key size and salt size). The @client_key, @client_salt, @server_key
* and @server_salt are convenience datums that point inside the key material. They may
* be %NULL.
*
* Returns: On success the size of the key material is returned,
* otherwise, %GNUTLS_E_SHORT_MEMORY_BUFFER if the buffer given is not
* sufficient, or a negative error code.
*
* Since 3.1.4
**/
int
gnutls_srtp_get_keys(gnutls_session_t session,
void *key_material,
unsigned int key_material_size,
gnutls_datum_t * client_key,
gnutls_datum_t * client_salt,
gnutls_datum_t * server_key,
gnutls_datum_t * server_salt)
{
int ret;
const srtp_profile_st *p;
gnutls_srtp_profile_t profile;
unsigned int msize;
uint8_t *km = key_material;
ret = gnutls_srtp_get_selected_profile(session, &profile);
if (ret < 0)
return gnutls_assert_val(ret);
p = get_profile(profile);
if (p == NULL)
return gnutls_assert_val(GNUTLS_E_UNKNOWN_ALGORITHM);
msize = 2 * (p->key_length + p->salt_length);
if (msize > key_material_size)
return gnutls_assert_val(GNUTLS_E_SHORT_MEMORY_BUFFER);
if (msize == 0)
return gnutls_assert_val(GNUTLS_E_INVALID_REQUEST);
ret =
gnutls_prf(session, sizeof("EXTRACTOR-dtls_srtp") - 1,
"EXTRACTOR-dtls_srtp", 0, 0, NULL, msize,
key_material);
if (ret < 0)
return gnutls_assert_val(ret);
if (client_key) {
client_key->data = km;
client_key->size = p->key_length;
}
if (server_key) {
server_key->data = km + p->key_length;
server_key->size = p->key_length;
}
if (client_salt) {
client_salt->data = km + 2 * p->key_length;
client_salt->size = p->salt_length;
}
if (server_salt) {
server_salt->data =
km + 2 * p->key_length + p->salt_length;
server_salt->size = p->salt_length;
}
return msize;
}
int print_info(gnutls_session_t session, int verbose, int print_cert)
{
const char *tmp;
gnutls_credentials_type_t cred;
gnutls_kx_algorithm_t kx;
unsigned char session_id[33];
size_t session_id_size = sizeof(session_id);
gnutls_srtp_profile_t srtp_profile;
gnutls_datum_t p;
char *desc;
int rc;
desc = gnutls_session_get_desc(session);
printf("- Description: %s\n", desc);
gnutls_free(desc);
/* print session ID */
gnutls_session_get_id(session, session_id, &session_id_size);
printf("- Session ID: %s\n",
raw_to_string(session_id, session_id_size));
/* print the key exchange's algorithm name
*/
kx = gnutls_kx_get(session);
cred = gnutls_auth_get_type(session);
switch (cred) {
#ifdef ENABLE_ANON
case GNUTLS_CRD_ANON:
if (kx == GNUTLS_KX_ANON_ECDH)
print_ecdh_info(session, "Anonymous ");
else
print_dh_info(session, "Anonymous ", verbose);
break;
#endif
#ifdef ENABLE_SRP
case GNUTLS_CRD_SRP:
/* This should be only called in server
* side.
*/
if (gnutls_srp_server_get_username(session) != NULL)
printf("- SRP authentication. Connected as '%s'\n",
gnutls_srp_server_get_username(session));
break;
#endif
#ifdef ENABLE_PSK
case GNUTLS_CRD_PSK:
/* This returns NULL in server side.
*/
if (gnutls_psk_client_get_hint(session) != NULL)
printf("- PSK authentication. PSK hint '%s'\n",
gnutls_psk_client_get_hint(session));
/* This returns NULL in client side.
*/
if (gnutls_psk_server_get_username(session) != NULL)
printf("- PSK authentication. Connected as '%s'\n",
gnutls_psk_server_get_username(session));
if (kx == GNUTLS_KX_DHE_PSK)
print_dh_info(session, "Ephemeral ", verbose);
if (kx == GNUTLS_KX_ECDHE_PSK)
print_ecdh_info(session, "Ephemeral ");
break;
#endif
case GNUTLS_CRD_IA:
printf("- TLS/IA authentication\n");
break;
case GNUTLS_CRD_CERTIFICATE:
{
char dns[256];
size_t dns_size = sizeof(dns);
unsigned int type;
/* This fails in client side */
if (gnutls_server_name_get
(session, dns, &dns_size, &type, 0) == 0) {
printf("- Given server name[%d]: %s\n",
type, dns);
}
}
if (print_cert)
print_cert_info(session, verbose, print_cert);
if (kx == GNUTLS_KX_DHE_RSA || kx == GNUTLS_KX_DHE_DSS)
print_dh_info(session, "Ephemeral ", verbose);
else if (kx == GNUTLS_KX_ECDHE_RSA
|| kx == GNUTLS_KX_ECDHE_ECDSA)
print_ecdh_info(session, "Ephemeral ");
}
tmp =
SU(gnutls_protocol_get_name
(gnutls_protocol_get_version(session)));
printf("- Version: %s\n", tmp);
tmp = SU(gnutls_kx_get_name(kx));
printf("- Key Exchange: %s\n", tmp);
if (gnutls_sign_algorithm_get(session) != GNUTLS_SIGN_UNKNOWN) {
tmp =
SU(gnutls_sign_get_name
(gnutls_sign_algorithm_get(session)));
printf("- Server Signature: %s\n", tmp);
}
if (gnutls_sign_algorithm_get_client(session) !=
GNUTLS_SIGN_UNKNOWN) {
tmp =
SU(gnutls_sign_get_name
(gnutls_sign_algorithm_get_client(session)));
printf("- Client Signature: %s\n", tmp);
}
tmp = SU(gnutls_cipher_get_name(gnutls_cipher_get(session)));
printf("- Cipher: %s\n", tmp);
tmp = SU(gnutls_mac_get_name(gnutls_mac_get(session)));
printf("- MAC: %s\n", tmp);
tmp =
SU(gnutls_compression_get_name
(gnutls_compression_get(session)));
printf("- Compression: %s\n", tmp);
#ifdef ENABLE_DTLS_SRTP
rc = gnutls_srtp_get_selected_profile(session, &srtp_profile);
if (rc == 0)
printf("- SRTP profile: %s\n",
gnutls_srtp_get_profile_name(srtp_profile));
#endif
#ifdef ENABLE_ALPN
rc = gnutls_alpn_get_selected_protocol(session, &p);
if (rc == 0)
printf("- Application protocol: %.*s\n", p.size, p.data);
#endif
if (verbose) {
gnutls_datum_t cb;
rc = gnutls_session_channel_binding(session,
GNUTLS_CB_TLS_UNIQUE,
&cb);
if (rc)
fprintf(stderr, "Channel binding error: %s\n",
gnutls_strerror(rc));
else {
size_t i;
printf("- Channel binding 'tls-unique': ");
for (i = 0; i < cb.size; i++)
printf("%02x", cb.data[i]);
printf("\n");
}
}
/* Warning: Do not print anything more here. The 'Compression:'
output MUST be the last non-verbose output. This is used by
Emacs starttls.el code. */
fflush(stdout);
return 0;
}
