static void fst_session_handle_setup_request(struct fst_iface *iface,
const struct ieee80211_mgmt *mgmt,
size_t frame_len)
{
struct fst_session *s;
const struct fst_setup_req *req;
struct fst_iface *new_iface = NULL;
struct fst_group *g;
u8 new_iface_peer_addr[ETH_ALEN];
const struct wpabuf *peer_mbies;
size_t plen;
if (frame_len < IEEE80211_HDRLEN + 1 + sizeof(*req)) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: too short (%zu < %zu)",
frame_len,
IEEE80211_HDRLEN + 1 + sizeof(*req));
return;
}
plen = frame_len - IEEE80211_HDRLEN - 1;
req = (const struct fst_setup_req *)
(((const u8 *) mgmt) + IEEE80211_HDRLEN + 1);
if (req->stie.element_id != WLAN_EID_SESSION_TRANSITION ||
req->stie.length < 11) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: invalid STIE");
return;
}
if (req->stie.new_band_id == req->stie.old_band_id) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: new and old band IDs are the same");
return;
}
g = fst_iface_get_group(iface);
if (plen > sizeof(*req)) {
fst_iface_update_mb_ie(iface, mgmt->sa, (const u8 *) (req + 1),
plen - sizeof(*req));
fst_printf_iface(iface, MSG_INFO,
"FST Request: MB IEs updated for " MACSTR,
MAC2STR(mgmt->sa));
}
peer_mbies = fst_iface_get_peer_mb_ie(iface, mgmt->sa);
if (peer_mbies) {
new_iface = fst_group_get_new_iface_by_stie_and_mbie(
g, wpabuf_head(peer_mbies), wpabuf_len(peer_mbies),
&req->stie, new_iface_peer_addr);
if (new_iface)
fst_printf_iface(iface, MSG_INFO,
"FST Request: new iface (%s:" MACSTR
") found by MB IEs",
fst_iface_get_name(new_iface),
MAC2STR(new_iface_peer_addr));
}
if (!new_iface) {
new_iface = fst_group_find_new_iface_by_stie(
g, iface, mgmt->sa, &req->stie,
new_iface_peer_addr);
if (new_iface)
fst_printf_iface(iface, MSG_INFO,
"FST Request: new iface (%s:" MACSTR
") found by others",
fst_iface_get_name(new_iface),
MAC2STR(new_iface_peer_addr));
}
if (!new_iface) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: new iface not found");
return;
}
s = fst_find_session_in_progress(mgmt->sa, g);
if (s) {
union fst_session_state_switch_extra evext = {
.to_initial = {
.reason = REASON_SETUP,
},
};
/*
* 10.32.2.2 Transitioning between states:
* Upon receipt of an FST Setup Request frame, the responder
* shall respond with an FST Setup Response frame unless it has
* a pending FST Setup Request frame addressed to the initiator
* and the responder has a numerically larger MAC address than
* the initiator’s MAC address, in which case, the responder
* shall delete the received FST Setup Request.
*/
if (os_memcmp(mgmt->da, mgmt->sa, ETH_ALEN) > 0) {
fst_printf_session(s, MSG_WARNING,
"FST Request dropped due to MAC comparison (our MAC is "
MACSTR ")",
MAC2STR(mgmt->da));
return;
}
if (!fst_session_is_ready_pending(s)) {
fst_printf_session(s, MSG_WARNING,
"FST Request from " MACSTR
" dropped due to inappropriate state %s",
MAC2STR(mgmt->da),
fst_session_state_name(s->state));
return;
}
/*
* If FST Setup Request arrived with the same FSTS ID as one we
* initialized before, it means the other side either didn't
* receive our FST Request or skipped it for some reason (for
* example, due to numerical MAC comparison).
*
* In this case, there's no need to tear down the session.
* Moreover, as FSTS ID is the same, the other side will
* associate this tear down with the session it initiated that
* will break the sync.
*/
if (le_to_host32(req->stie.fsts_id) != s->data.fsts_id)
fst_session_send_tear_down(s);
else
fst_printf_session(s, MSG_WARNING,
"Skipping TearDown as the FST request has the same FSTS ID as initiated");
fst_session_set_state(s, FST_SESSION_STATE_INITIAL, &evext);
fst_session_stt_disarm(s);
fst_printf_session(s, MSG_WARNING, "reset due to FST request");
}
s = fst_session_create(g);
if (!s) {
fst_printf(MSG_WARNING,
"FST Request dropped: cannot create session for %s and %s",
fst_iface_get_name(iface),
fst_iface_get_name(new_iface));
return;
}
fst_session_set_iface(s, iface, TRUE);
fst_session_set_peer_addr(s, mgmt->sa, TRUE);
fst_session_set_iface(s, new_iface, FALSE);
fst_session_set_peer_addr(s, new_iface_peer_addr, FALSE);
fst_session_set_llt(s, FST_LLT_VAL_TO_MS(le_to_host32(req->llt)));
s->data.pending_setup_req_dlgt = req->dialog_token;
s->data.fsts_id = le_to_host32(req->stie.fsts_id);
fst_session_stt_arm(s);
fst_session_notify_ctrl(s, EVENT_FST_SETUP, NULL);
fst_session_set_state(s, FST_SESSION_STATE_SETUP_COMPLETION, NULL);
}
static void fst_plugin_connect_next ()
{
FSTNode *node;
FSTSession *sess;
List *l;
int count = 0, nsessions, nconnecting = 0;
nsessions = config_get_int (FST_PLUGIN->conf, "main/additional_sessions=0");
if (nsessions > FST_MAX_ADDITIONAL_SESSIONS)
nsessions = FST_MAX_ADDITIONAL_SESSIONS;
/* determine number of currently connecting sessions */
nconnecting = (FST_PLUGIN->session && FST_PLUGIN->session->state != SessEstablished) ? 1 : 0;
for (l = FST_PLUGIN->sessions; l; l = l->next)
{
assert (l->data);
if (((FSTSession*)l->data)->state != SessEstablished)
nconnecting++;
}
/* connect to head node in node cache */
while ((!FST_PLUGIN->session ||
list_length (FST_PLUGIN->sessions) <= nsessions) &&
nconnecting <= FST_SESSION_MAX_CONCURRENT_ATTEMPTS)
{
if (!(node = fst_nodecache_get_front (FST_PLUGIN->nodecache)))
{
/* node cache empty */
FST_ERR ("All attempts at contacting peers have failed. Trying default nodes file.");
if (fst_nodecache_load (FST_PLUGIN->nodecache,
stringf ("%s/FastTrack/nodes", platform_data_dir())) <= 0 ||
!(node = fst_nodecache_get_front (FST_PLUGIN->nodecache)))
{
FST_ERR ("Failed to load default nodes file. Perhaps your installation is corrupt?");
return;
}
}
/* don't connect anywhere we're already connected to */
if (node->session)
{
/* move node to back of cache so next loop
* uses a different one */
fst_nodecache_move (FST_PLUGIN->nodecache, node, NodeInsertBack);
fst_node_release (node);
/* we've probably run out of nodes at this point, so
* wait a while until we get some more (continuing
* tends to produce an infinite loop) */
if (count++ >= list_length (FST_PLUGIN->sessions))
return;
continue;
}
/* don't connect to anywhere too close to an existing node */
if (dataset_lookup (FST_PLUGIN->peers, &node, sizeof(node)))
{
#if 0
FST_DBG_2 ("not connecting to close node %s:%d",
node->host, node->port);
#endif
/* move node to back of cache so next loop
* uses a different one */
fst_nodecache_move (FST_PLUGIN->nodecache, node, NodeInsertBack);
fst_node_release (node);
/* we've probably run out of nodes at this point, so
* wait a while until we get some more (continuing
* tends to produce an infinite loop) */
if (count++ >= list_length (FST_PLUGIN->sessions))
return;
continue;
}
/* don't connect to invalid ips */
if (!fst_utils_ip_routable (net_ip (node->host)))
{
FST_DBG_2 ("not connecting to unroutable node %s:%d",
node->host, node->port);
/* remove this node from cache */
fst_nodecache_remove (FST_PLUGIN->nodecache, node);
fst_node_release (node);
continue;
}
/* don't connect to banned ips */
if (config_get_int (FST_PLUGIN->conf, "main/banlist_filter=0") &&
fst_ipset_contains (FST_PLUGIN->banlist, net_ip (node->host)))
{
FST_DBG_2 ("not connecting to banned supernode %s:%d",
node->host, node->port);
/* remove this node from cache */
fst_nodecache_remove (FST_PLUGIN->nodecache, node);
fst_node_release (node);
continue;
}
/* create session and connect */
sess = fst_session_create (fst_plugin_session_callback);
if (!fst_session_connect (sess, node))
{
/* free session */
fst_session_free (sess);
sess = NULL;
/* TODO: check if name resolution in fst_session_connect() failed */
/* network down, wait a while before retrying */
FST_WARN_1 ("Internet connection seems down, sleeping...",
FST_SESSION_NETFAIL_INTERVAL / SECONDS);
/* move node to back of cache so next loop uses a different one; this
* won't help if the network really is down, but might under other
* circumstances */
fst_nodecache_move (FST_PLUGIN->nodecache, node, NodeInsertBack);
fst_node_release (node);
/* just wait until fst_plugin_try_connect() is next called */
return;
}
/* move node to back of cache so next loop uses a different one */
fst_nodecache_move (FST_PLUGIN->nodecache, node, NodeInsertBack);
fst_node_release (node);
/* We now have a new session object. Use it as primary session if we
* don't already have one. Otherwise use it as an additional one. */
if (!FST_PLUGIN->session)
{
FST_PLUGIN->session = sess;
}
else
{
FST_PLUGIN->sessions = list_prepend (FST_PLUGIN->sessions, sess);
}
nconnecting++;
}
/* don't ping if we're currently connected */
if (FST_PLUGIN->stats->sessions > 0)
return;
/* We started a connection attempt with the head node from nodecache.
* Try to quickly find some online nodes with udp in parallel now.
*/
if (FST_PLUGIN->discover && FST_PLUGIN->discover->pinged_nodes == 0)
{
List *item = FST_PLUGIN->nodecache->list;
int i = 0;
while (i < FST_UDP_DISCOVER_MAX_PINGS && item && item->data)
{
node = (FSTNode*)item->data;
if (!fst_udp_discover_ping_node (FST_PLUGIN->discover, node))
{
/* This may fail due to the network being down. While
* we could handle this in a special way doing nothing
* works fine if being somewhat inefficient. */
}
item = item->next;
i++;
}
FST_DBG_1 ("discovery cycle started with %d UDP pings", i);
}
}
static void fst_session_handle_setup_request(struct fst_iface *iface,
const struct ieee80211_mgmt *mgmt,
size_t frame_len)
{
struct fst_session *s;
const struct fst_setup_req *req;
struct fst_iface *new_iface = NULL;
struct fst_group *g;
u8 new_iface_peer_addr[ETH_ALEN];
size_t plen;
if (frame_len < IEEE80211_HDRLEN + 1 + sizeof(*req)) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: too short (%zu < %zu)",
frame_len,
IEEE80211_HDRLEN + 1 + sizeof(*req));
return;
}
plen = frame_len - IEEE80211_HDRLEN - 1;
req = (const struct fst_setup_req *)
(((const u8 *) mgmt) + IEEE80211_HDRLEN + 1);
if (req->stie.element_id != WLAN_EID_SESSION_TRANSITION ||
req->stie.length < 11) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: invalid STIE");
return;
}
if (req->stie.new_band_id == req->stie.old_band_id) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: new and old band IDs are the same");
return;
}
g = fst_iface_get_group(iface);
if (plen > sizeof(*req)) {
fst_iface_update_mb_ie(iface, mgmt->sa, (const u8 *) (req + 1),
plen - sizeof(*req));
fst_printf_iface(iface, MSG_INFO,
"FST Request: MB IEs updated for " MACSTR,
MAC2STR(mgmt->sa));
}
new_iface = fst_group_get_peer_other_connection(iface, mgmt->sa,
req->stie.new_band_id,
new_iface_peer_addr);
if (!new_iface) {
fst_printf_iface(iface, MSG_WARNING,
"FST Request dropped: new iface not found");
return;
}
fst_printf_iface(iface, MSG_INFO,
"FST Request: new iface (%s:" MACSTR ") found",
fst_iface_get_name(new_iface),
MAC2STR(new_iface_peer_addr));
s = fst_find_session_in_progress(mgmt->sa, g);
if (s) {
union fst_session_state_switch_extra evext = {
.to_initial = {
.reason = REASON_SETUP,
},
};
/*
* 10.32.2.2 Transitioning between states:
* Upon receipt of an FST Setup Request frame, the responder
* shall respond with an FST Setup Response frame unless it has
* a pending FST Setup Request frame addressed to the initiator
* and the responder has a numerically larger MAC address than
* the initiator’s MAC address, in which case, the responder
* shall delete the received FST Setup Request.
*/
if (fst_session_is_ready_pending(s) &&
/* waiting for Setup Response */
os_memcmp(mgmt->da, mgmt->sa, ETH_ALEN) > 0) {
fst_printf_session(s, MSG_WARNING,
"FST Request dropped due to MAC comparison (our MAC is "
MACSTR ")",
MAC2STR(mgmt->da));
return;
}
/*
* State is SETUP_COMPLETION (either in transition or not) or
* TRANSITION_DONE (in transition).
* Setup Request arriving in this state could mean:
* 1. peer sent it before receiving our Setup Request (race
* condition)
* 2. peer didn't receive our Setup Response. Peer is retrying
* after STT timeout
* 3. peer's FST state machines are out of sync due to some
* other reason
*
* We will reset our session and create a new one instead.
*/
fst_printf_session(s, MSG_WARNING,
"resetting due to FST request");
/*
* If FST Setup Request arrived with the same FSTS ID as one we
* initialized before, there's no need to tear down the session.
* Moreover, as FSTS ID is the same, the other side will
* associate this tear down with the session it initiated that
* will break the sync.
*/
if (le_to_host32(req->stie.fsts_id) != s->data.fsts_id)
fst_session_send_tear_down(s);
else
fst_printf_session(s, MSG_WARNING,
"Skipping TearDown as the FST request has the same FSTS ID as initiated");
fst_session_set_state(s, FST_SESSION_STATE_INITIAL, &evext);
fst_session_stt_disarm(s);
}
s = fst_session_create(g);
if (!s) {
fst_printf(MSG_WARNING,
"FST Request dropped: cannot create session for %s and %s",
fst_iface_get_name(iface),
fst_iface_get_name(new_iface));
return;
}
fst_session_set_iface(s, iface, TRUE);
fst_session_set_peer_addr(s, mgmt->sa, TRUE);
fst_session_set_iface(s, new_iface, FALSE);
fst_session_set_peer_addr(s, new_iface_peer_addr, FALSE);
fst_session_set_llt(s, FST_LLT_VAL_TO_MS(le_to_host32(req->llt)));
s->data.pending_setup_req_dlgt = req->dialog_token;
s->data.fsts_id = le_to_host32(req->stie.fsts_id);
fst_session_stt_arm(s);
fst_session_notify_ctrl(s, EVENT_FST_SETUP, NULL);
fst_session_set_state(s, FST_SESSION_STATE_SETUP_COMPLETION, NULL);
}
