/* Return values
* -1 -> Internal error
* 0 -> Not available
* 1 -> Tuple returned, need to do auth, then enable cipher
* 2 -> Tuple returned, need to enable cipher
*/
int auth_get_tuple_for_subscr(struct gsm_auth_tuple *atuple,
struct gsm_subscriber *subscr, int key_seq)
{
struct gsm_auth_info ainfo;
int i, rc;
/* Get subscriber info (if any) */
rc = db_get_authinfo_for_subscr(&ainfo, subscr);
if (rc < 0) {
LOGP(DMM, LOGL_NOTICE,
"No retrievable Ki for subscriber, skipping auth\n");
return rc == -ENOENT ? AUTH_NOT_AVAIL : -1;
}
/* If possible, re-use the last tuple and skip auth */
rc = db_get_lastauthtuple_for_subscr(atuple, subscr);
if ((rc == 0) &&
(key_seq != GSM_KEY_SEQ_INVAL) &&
(atuple->use_count < 3))
{
atuple->use_count++;
db_sync_lastauthtuple_for_subscr(atuple, subscr);
DEBUGP(DMM, "Auth tuple use < 3, just doing ciphering\n");
return AUTH_DO_CIPH;
}
/* Generate a new one */
atuple->use_count = 1;
atuple->key_seq = (atuple->key_seq + 1) % 7;
for (i=0; i<sizeof(atuple->rand); i++)
atuple->rand[i] = random() & 0xff;
switch (ainfo.auth_algo) {
case AUTH_ALGO_NONE:
DEBUGP(DMM, "No authentication for subscriber\n");
return 0;
case AUTH_ALGO_XOR:
if (_use_xor(&ainfo, atuple))
return 0;
break;
case AUTH_ALGO_COMP128v1:
if (_use_comp128_v1(&ainfo, atuple))
return 0;
break;
default:
DEBUGP(DMM, "Unsupported auth type algo_id=%d\n",
ainfo.auth_algo);
return 0;
}
db_sync_lastauthtuple_for_subscr(atuple, subscr);
DEBUGP(DMM, "Need to do authentication and ciphering\n");
return AUTH_DO_AUTH_THAN_CIPH;
}
/* Return values
* -1 -> Internal error
* 0 -> Not available
* 1 -> Tuple returned, need to do auth, then enable cipher
* 2 -> Tuple returned, need to enable cipher
*/
int auth_get_tuple_for_subscr(struct gsm_auth_tuple *atuple,
struct gsm_subscriber *subscr, int key_seq)
{
struct gsm_auth_info ainfo;
int rc;
/* Get subscriber info (if any) */
rc = db_get_authinfo_for_subscr(&ainfo, subscr);
if (rc < 0) {
LOGP(DMM, LOGL_NOTICE,
"No retrievable Ki for subscriber, skipping auth\n");
return rc == -ENOENT ? AUTH_NOT_AVAIL : AUTH_ERROR;
}
/* If possible, re-use the last tuple and skip auth */
rc = db_get_lastauthtuple_for_subscr(atuple, subscr);
if ((rc == 0) &&
(key_seq != GSM_KEY_SEQ_INVAL) &&
(key_seq == atuple->key_seq) &&
(atuple->use_count < 3))
{
atuple->use_count++;
db_sync_lastauthtuple_for_subscr(atuple, subscr);
DEBUGP(DMM, "Auth tuple use < 3, just doing ciphering\n");
return AUTH_DO_CIPH;
}
/* Generate a new one */
if (rc != 0) {
/* If db_get_lastauthtuple_for_subscr() returned nothing, make
* sure the atuple memory is initialized to zero and thus start
* off with key_seq = 0. */
memset(atuple, 0, sizeof(*atuple));
} else {
/* If db_get_lastauthtuple_for_subscr() returned a previous
* tuple, use the next key_seq. */
atuple->key_seq = (atuple->key_seq + 1) % 7;
}
atuple->use_count = 1;
if (RAND_bytes(atuple->vec.rand, sizeof(atuple->vec.rand)) != 1) {
LOGP(DMM, LOGL_NOTICE, "RAND_bytes failed, can't generate new auth tuple\n");
return AUTH_ERROR;
}
switch (ainfo.auth_algo) {
case AUTH_ALGO_NONE:
DEBUGP(DMM, "No authentication for subscriber\n");
return AUTH_NOT_AVAIL;
case AUTH_ALGO_XOR:
if (_use_xor(&ainfo, atuple))
return AUTH_NOT_AVAIL;
break;
case AUTH_ALGO_COMP128v1:
if (_use_comp128_v1(&ainfo, atuple))
return AUTH_NOT_AVAIL;
break;
default:
DEBUGP(DMM, "Unsupported auth type algo_id=%d\n",
ainfo.auth_algo);
return AUTH_NOT_AVAIL;
}
db_sync_lastauthtuple_for_subscr(atuple, subscr);
DEBUGP(DMM, "Need to do authentication and ciphering\n");
return AUTH_DO_AUTH_THEN_CIPH;
}
