/* agent must be locked */
static struct ice_candidate_pair *__learned_candidate(struct ice_agent *ag, struct packet_stream *ps,
struct sockaddr_in6 *src, struct interface_address *ifa, unsigned long priority)
{
struct ice_candidate *cand, *old_cand;
struct ice_candidate_pair *pair;
struct call *call = ag->call;
cand = g_slice_alloc0(sizeof(*cand));
cand->component_id = ps->component;
cand->transport = ITP_UDP;
cand->priority = priority;
cand->endpoint.ip46 = src->sin6_addr;
cand->endpoint.port = ntohs(src->sin6_port);
cand->type = ICT_PRFLX;
__cand_ice_foundation(call, cand);
old_cand = __foundation_lookup(ag, &cand->foundation, ps->component);
if (old_cand && old_cand->priority > priority) {
/* this is possible if two distinct requests are received from the same NAT IP
* address, but from different ports. we cannot distinguish such candidates and
* will drop the one with the lower priority */
g_slice_free1(sizeof(*cand), cand);
pair = __pair_lookup(ag, old_cand, ifa);
if (pair)
goto out; /* nothing to do */
cand = old_cand;
goto pair;
}
g_queue_push_tail(&ag->remote_candidates, cand);
g_hash_table_insert(ag->candidate_hash, cand, cand);
g_hash_table_insert(ag->foundation_hash, cand, cand);
pair:
pair = __pair_candidate(ifa, ag, cand, ps);
PAIR_SET(pair, LEARNED);
__all_pairs_list(ag);
out:
return pair;
}
/* agent must be locked */
static struct ice_candidate_pair *__learned_candidate(struct ice_agent *ag, struct stream_fd *sfd,
const endpoint_t *src, unsigned long priority)
{
struct ice_candidate *cand, *old_cand;
struct ice_candidate_pair *pair;
struct call *call = ag->call;
struct packet_stream *ps = sfd->stream;
cand = g_slice_alloc0(sizeof(*cand));
cand->component_id = ps->component;
cand->transport = sfd->local_intf->spec->local_address.type; // XXX add socket type into socket_t?
cand->priority = priority;
cand->endpoint = *src;
cand->type = ICT_PRFLX;
__cand_ice_foundation(call, cand);
old_cand = __foundation_lookup(ag, &cand->foundation, ps->component);
if (old_cand && old_cand->priority > priority) {
/* this is possible if two distinct requests are received from the same NAT IP
* address, but from different ports. we cannot distinguish such candidates and
* will drop the one with the lower priority */
g_slice_free1(sizeof(*cand), cand);
pair = __pair_lookup(ag, old_cand, sfd->local_intf);
if (pair)
goto out; /* nothing to do */
cand = old_cand;
goto pair;
}
g_queue_push_tail(&ag->remote_candidates, cand);
g_hash_table_insert(ag->candidate_hash, cand, cand);
g_hash_table_insert(ag->foundation_hash, cand, cand);
pair:
pair = __pair_candidate(sfd, ag, cand);
PAIR_SET(pair, LEARNED);
__all_pairs_list(ag);
out:
return pair;
}
/* initializes "out" */
static void __get_complete_components(GQueue *out, struct ice_agent *ag, GTree *t, unsigned int flag) {
GQueue compo1 = G_QUEUE_INIT;
GList *l;
struct ice_candidate_pair *pair1, *pairX;
struct ice_candidate *cand;
unsigned int i;
__get_pairs_by_component(&compo1, t, 1);
g_queue_init(out);
for (l = compo1.head; l; l = l->next) {
pair1 = l->data;
g_queue_clear(out);
g_queue_push_tail(out, pair1);
for (i = 2; i <= ag->active_components; i++) {
cand = __foundation_lookup(ag, &pair1->remote_candidate->foundation, i);
if (!cand)
goto next_foundation;
pairX = __pair_lookup(ag, cand, pair1->local_address);
if (!pairX)
goto next_foundation;
if (!bf_isset(&pairX->pair_flags, flag))
goto next_foundation;
g_queue_push_tail(out, pairX);
}
goto found;
next_foundation:
;
}
/* nothing found */
g_queue_clear(out);
found:
g_queue_clear(&compo1);
}
/* call is locked in R */
int ice_response(struct packet_stream *ps, struct sockaddr_in6 *src, struct in6_addr *dst,
struct stun_attrs *attrs, u_int32_t transaction[3])
{
struct ice_candidate_pair *pair, *opair;
struct ice_agent *ag;
struct call_media *media = ps->media;
const char *err;
unsigned int component;
struct ice_candidate *cand;
struct interface_address *ifa;
int ret, was_ctl;
__DBG("received ICE response from %s on %s", smart_ntop_port_buf(src), smart_ntop_buf(dst));
ag = media->ice_agent;
if (!ag)
return -1;
atomic64_set(&ag->last_activity, poller_now);
mutex_lock(&ag->lock);
pair = g_hash_table_lookup(ag->transaction_hash, transaction);
err = "ICE/STUN response with unknown transaction received";
if (!pair)
goto err_unlock;
was_ctl = pair->was_controlling;
mutex_unlock(&ag->lock);
ifa = pair->local_address;
ilog(LOG_DEBUG, "Received ICE/STUN response code %u for candidate pair "PAIR_FORMAT" from %s to %s",
attrs->error_code, PAIR_FMT(pair),
smart_ntop_ep_buf(&pair->remote_candidate->endpoint),
smart_ntop_buf(&ifa->addr));
/* verify endpoints */
err = "ICE/STUN response received, but source address didn't match remote candidate address";
if (memcmp(&src->sin6_addr, &pair->remote_candidate->endpoint.ip46, sizeof(src->sin6_addr)))
goto err;
if (ntohs(src->sin6_port) != pair->remote_candidate->endpoint.port)
goto err;
err = "ICE/STUN response received, but destination address didn't match local interface address";
if (memcmp(dst, &ifa->addr, sizeof(*dst)))
goto err;
if (pair->packet_stream != ps)
goto err;
PAIR_CLEAR(pair, IN_PROGRESS);
ret = 0;
/* handle all errors */
if (attrs->error_code) {
err = "ICE/STUN error received";
if (attrs->error_code != 487)
goto err;
__role_change(ag, !was_ctl);
__trigger_check(pair);
goto out;
}
/* we don't discover peer reflexive here (RFC 5245 7.1.3.2.1) as we don't expect to be behind NAT */
/* we also skip parts of 7.1.3.2.2 as we don't do server reflexive */
mutex_lock(&ag->lock);
/* check if we're in the final (controlling) phase */
if (pair->was_nominated && PAIR_CLEAR(pair, TO_USE)) {
ilog(LOG_DEBUG, "Setting nominated ICE candidate pair "PAIR_FORMAT" as valid", PAIR_FMT(pair));
PAIR_SET(pair, VALID);
g_tree_insert(ag->valid_pairs, pair, pair);
ret = __check_valid(ag);
goto out_unlock;
}
if (PAIR_SET(pair, SUCCEEDED))
goto out_unlock;
ilog(LOG_DEBUG, "Setting ICE candidate pair "PAIR_FORMAT" as succeeded", PAIR_FMT(pair));
g_tree_insert(ag->succeeded_pairs, pair, pair);
if (!ag->start_nominating.tv_sec) {
if (__check_succeeded_complete(ag)) {
ag->start_nominating = g_now;
timeval_add_usec(&ag->start_nominating, 100000);
__agent_schedule_abs(ag, &ag->start_nominating);
}
}
/* now unfreeze all other pairs from the same foundation */
for (component = 1; component <= MAX_COMPONENTS; component++) {
if (component == ps->component)
continue;
cand = __foundation_lookup(ag, &pair->remote_candidate->foundation, component);
if (!cand)
continue;
opair = __pair_lookup(ag, cand, ifa);
if (!opair)
continue;
if (PAIR_ISSET(opair, FAILED))
continue;
if (!PAIR_CLEAR(opair, FROZEN))
continue;
ilog(LOG_DEBUG, "Unfreezing related ICE pair "PAIR_FORMAT, PAIR_FMT(opair));
}
/* if this was previously nominated by the peer, it's now valid */
if (PAIR_ISSET(pair, NOMINATED)) {
PAIR_SET(pair, VALID);
g_tree_insert(ag->valid_pairs, pair, pair);
if (!AGENT_ISSET(ag, CONTROLLING))
ret = __check_valid(ag);
}
out_unlock:
mutex_unlock(&ag->lock);
out:
return ret;
err_unlock:
mutex_unlock(&ag->lock);
err:
if (err)
ilog(LOG_NOTICE, "%s (from %s on interface %s)",
err, smart_ntop_port_buf(src), smart_ntop_buf(dst));
if (pair && attrs->error_code)
__fail_pair(pair);
return 0;
}