* See the GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with GNU CC; see the file COPYING. If not, write to
- * the Free Software Foundation, 59 Temple Place - Suite 330,
- * Boston, MA 02111-1307, USA.
+ * along with GNU CC; see the file COPYING. If not, see
+ * <http://www.gnu.org/licenses/>.
*
* Please send any bug reports or fixes you make to the
* email address(es):
/* Initialize the object handling fields. */
atomic_set(&asoc->base.refcnt, 1);
- asoc->base.dead = false;
/* Initialize the bind addr area. */
sctp_bind_addr_init(&asoc->base.bind_addr, ep->base.bind_addr.port);
asoc->state = SCTP_STATE_CLOSED;
asoc->cookie_life = ms_to_ktime(sp->assocparams.sasoc_cookie_life);
- asoc->frag_point = 0;
asoc->user_frag = sp->user_frag;
/* Set the association max_retrans and RTO values from the
asoc->rto_max = msecs_to_jiffies(sp->rtoinfo.srto_max);
asoc->rto_min = msecs_to_jiffies(sp->rtoinfo.srto_min);
- asoc->overall_error_count = 0;
-
/* Initialize the association's heartbeat interval based on the
* sock configured value.
*/
*/
asoc->param_flags = sp->param_flags;
- /* Initialize the maximum mumber of new data packets that can be sent
+ /* Initialize the maximum number of new data packets that can be sent
* in a burst.
*/
asoc->max_burst = sp->max_burst;
/* initialize association timers */
- asoc->timeouts[SCTP_EVENT_TIMEOUT_NONE] = 0;
asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_COOKIE] = asoc->rto_initial;
asoc->timeouts[SCTP_EVENT_TIMEOUT_T1_INIT] = asoc->rto_initial;
asoc->timeouts[SCTP_EVENT_TIMEOUT_T2_SHUTDOWN] = asoc->rto_initial;
- asoc->timeouts[SCTP_EVENT_TIMEOUT_T3_RTX] = 0;
- asoc->timeouts[SCTP_EVENT_TIMEOUT_T4_RTO] = 0;
/* sctpimpguide Section 2.12.2
* If the 'T5-shutdown-guard' timer is used, it SHOULD be set to the
asoc->timeouts[SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD]
= 5 * asoc->rto_max;
- asoc->timeouts[SCTP_EVENT_TIMEOUT_HEARTBEAT] = 0;
asoc->timeouts[SCTP_EVENT_TIMEOUT_SACK] = asoc->sackdelay;
asoc->timeouts[SCTP_EVENT_TIMEOUT_AUTOCLOSE] = sp->autoclose * HZ;
asoc->max_init_timeo =
msecs_to_jiffies(sp->initmsg.sinit_max_init_timeo);
- /* Allocate storage for the ssnmap after the inbound and outbound
- * streams have been negotiated during Init.
- */
- asoc->ssnmap = NULL;
-
/* Set the local window size for receive.
* This is also the rcvbuf space per association.
* RFC 6 - A SCTP receiver MUST be able to receive a minimum of
asoc->a_rwnd = asoc->rwnd;
- asoc->rwnd_over = 0;
- asoc->rwnd_press = 0;
-
/* Use my own max window until I learn something better. */
asoc->peer.rwnd = SCTP_DEFAULT_MAXWINDOW;
- /* Set the sndbuf size for transmit. */
- asoc->sndbuf_used = 0;
-
/* Initialize the receive memory counter */
atomic_set(&asoc->rmem_alloc, 0);
init_waitqueue_head(&asoc->wait);
asoc->c.my_vtag = sctp_generate_tag(ep);
- asoc->peer.i.init_tag = 0; /* INIT needs a vtag of 0. */
- asoc->c.peer_vtag = 0;
- asoc->c.my_ttag = 0;
- asoc->c.peer_ttag = 0;
asoc->c.my_port = ep->base.bind_addr.port;
asoc->c.initial_tsn = sctp_generate_tsn(ep);
asoc->adv_peer_ack_point = asoc->ctsn_ack_point;
asoc->highest_sacked = asoc->ctsn_ack_point;
asoc->last_cwr_tsn = asoc->ctsn_ack_point;
- asoc->unack_data = 0;
/* ADDIP Section 4.1 Asconf Chunk Procedures
*
/* Make an empty list of remote transport addresses. */
INIT_LIST_HEAD(&asoc->peer.transport_addr_list);
- asoc->peer.transport_count = 0;
/* RFC 2960 5.1 Normal Establishment of an Association
*
* already received one packet.]
*/
asoc->peer.sack_needed = 1;
- asoc->peer.sack_cnt = 0;
asoc->peer.sack_generation = 1;
/* Assume that the peer will tell us if he recognizes ASCONF
* as part of INIT exchange.
- * The sctp_addip_noauth option is there for backward compatibilty
+ * The sctp_addip_noauth option is there for backward compatibility
* and will revert old behavior.
*/
- asoc->peer.asconf_capable = 0;
if (net->sctp.addip_noauth)
asoc->peer.asconf_capable = 1;
- asoc->asconf_addr_del_pending = NULL;
- asoc->src_out_of_asoc_ok = 0;
- asoc->new_transport = NULL;
/* Create an input queue. */
sctp_inq_init(&asoc->base.inqueue);
if (!sctp_ulpq_init(&asoc->ulpq, asoc))
goto fail_init;
- memset(&asoc->peer.tsn_map, 0, sizeof(struct sctp_tsnmap));
-
- asoc->need_ecne = 0;
-
- asoc->assoc_id = 0;
-
/* Assume that peer would support both address types unless we are
* told otherwise.
*/
asoc->default_timetolive = sp->default_timetolive;
asoc->default_rcv_context = sp->default_rcv_context;
- /* SCTP_GET_ASSOC_STATS COUNTERS */
- memset(&asoc->stats, 0, sizeof(struct sctp_priv_assoc_stats));
-
/* AUTH related initializations */
INIT_LIST_HEAD(&asoc->endpoint_shared_keys);
err = sctp_auth_asoc_copy_shkeys(ep, asoc, gfp);
goto fail_init;
asoc->active_key_id = ep->active_key_id;
- asoc->asoc_shared_key = NULL;
- asoc->default_hmac_id = 0;
/* Save the hmacs and chunks list into this association */
if (ep->auth_hmacs_list)
memcpy(asoc->c.auth_hmacs, ep->auth_hmacs_list,
*/
struct sctp_chunk *sctp_get_ecne_prepend(struct sctp_association *asoc)
{
- struct sctp_chunk *chunk;
+ if (!asoc->need_ecne)
+ return NULL;
/* Send ECNE if needed.
* Not being able to allocate a chunk here is not deadly.
*/
- if (asoc->need_ecne)
- chunk = sctp_make_ecne(asoc, asoc->last_ecne_tsn);
- else
- chunk = NULL;
-
- return chunk;
+ return sctp_make_ecne(asoc, asoc->last_ecne_tsn);
}
/*
}
}
- /* SCTP-AUTH: Save the peer parameters from the new assocaitions
+ /* SCTP-AUTH: Save the peer parameters from the new associations
* and also move the association shared keys over
*/
kfree(asoc->peer.peer_random);
}
/* Update the retran path for sending a retransmitted packet.
- * Round-robin through the active transports, else round-robin
- * through the inactive transports as this is the next best thing
- * we can try.
+ * See also RFC4960, 6.4. Multi-Homed SCTP Endpoints:
+ *
+ * When there is outbound data to send and the primary path
+ * becomes inactive (e.g., due to failures), or where the
+ * SCTP user explicitly requests to send data to an
+ * inactive destination transport address, before reporting
+ * an error to its ULP, the SCTP endpoint should try to send
+ * the data to an alternate active destination transport
+ * address if one exists.
+ *
+ * When retransmitting data that timed out, if the endpoint
+ * is multihomed, it should consider each source-destination
+ * address pair in its retransmission selection policy.
+ * When retransmitting timed-out data, the endpoint should
+ * attempt to pick the most divergent source-destination
+ * pair from the original source-destination pair to which
+ * the packet was transmitted.
+ *
+ * Note: Rules for picking the most divergent source-destination
+ * pair are an implementation decision and are not specified
+ * within this document.
+ *
+ * Our basic strategy is to round-robin transports in priorities
+ * according to sctp_state_prio_map[] e.g., if no such
+ * transport with state SCTP_ACTIVE exists, round-robin through
+ * SCTP_UNKNOWN, etc. You get the picture.
*/
-void sctp_assoc_update_retran_path(struct sctp_association *asoc)
+static const u8 sctp_trans_state_to_prio_map[] = {
+ [SCTP_ACTIVE] = 3, /* best case */
+ [SCTP_UNKNOWN] = 2,
+ [SCTP_PF] = 1,
+ [SCTP_INACTIVE] = 0, /* worst case */
+};
+
+static u8 sctp_trans_score(const struct sctp_transport *trans)
{
- struct sctp_transport *t, *next;
- struct list_head *head = &asoc->peer.transport_addr_list;
- struct list_head *pos;
+ return sctp_trans_state_to_prio_map[trans->state];
+}
- if (asoc->peer.transport_count == 1)
- return;
+static struct sctp_transport *sctp_trans_elect_best(struct sctp_transport *curr,
+ struct sctp_transport *best)
+{
+ if (best == NULL)
+ return curr;
- /* Find the next transport in a round-robin fashion. */
- t = asoc->peer.retran_path;
- pos = &t->transports;
- next = NULL;
+ return sctp_trans_score(curr) > sctp_trans_score(best) ? curr : best;
+}
- while (1) {
- /* Skip the head. */
- if (pos->next == head)
- pos = head->next;
- else
- pos = pos->next;
+void sctp_assoc_update_retran_path(struct sctp_association *asoc)
+{
+ struct sctp_transport *trans = asoc->peer.retran_path;
+ struct sctp_transport *trans_next = NULL;
- t = list_entry(pos, struct sctp_transport, transports);
+ /* We're done as we only have the one and only path. */
+ if (asoc->peer.transport_count == 1)
+ return;
+ /* If active_path and retran_path are the same and active,
+ * then this is the only active path. Use it.
+ */
+ if (asoc->peer.active_path == asoc->peer.retran_path &&
+ asoc->peer.active_path->state == SCTP_ACTIVE)
+ return;
- /* We have exhausted the list, but didn't find any
- * other active transports. If so, use the next
- * transport.
- */
- if (t == asoc->peer.retran_path) {
- t = next;
+ /* Iterate from retran_path's successor back to retran_path. */
+ for (trans = list_next_entry(trans, transports); 1;
+ trans = list_next_entry(trans, transports)) {
+ /* Manually skip the head element. */
+ if (&trans->transports == &asoc->peer.transport_addr_list)
+ continue;
+ if (trans->state == SCTP_UNCONFIRMED)
+ continue;
+ trans_next = sctp_trans_elect_best(trans, trans_next);
+ /* Active is good enough for immediate return. */
+ if (trans_next->state == SCTP_ACTIVE)
break;
- }
-
- /* Try to find an active transport. */
-
- if ((t->state == SCTP_ACTIVE) ||
- (t->state == SCTP_UNKNOWN)) {
+ /* We've reached the end, time to update path. */
+ if (trans == asoc->peer.retran_path)
break;
- } else {
- /* Keep track of the next transport in case
- * we don't find any active transport.
- */
- if (t->state != SCTP_UNCONFIRMED && !next)
- next = t;
- }
}
- if (t)
- asoc->peer.retran_path = t;
- else
- t = asoc->peer.retran_path;
+ if (trans_next != NULL)
+ asoc->peer.retran_path = trans_next;
- pr_debug("%s: association:%p addr:%pISpc\n", __func__, asoc,
- &t->ipaddr.sa);
+ pr_debug("%s: association:%p updated new path to addr:%pISpc\n",
+ __func__, asoc, &asoc->peer.retran_path->ipaddr.sa);
}
-/* Choose the transport for sending retransmit packet. */
-struct sctp_transport *sctp_assoc_choose_alter_transport(
- struct sctp_association *asoc, struct sctp_transport *last_sent_to)
+struct sctp_transport *
+sctp_assoc_choose_alter_transport(struct sctp_association *asoc,
+ struct sctp_transport *last_sent_to)
{
/* If this is the first time packet is sent, use the active path,
* else use the retran path. If the last packet was sent over the
* retran path, update the retran path and use it.
*/
- if (!last_sent_to)
+ if (last_sent_to == NULL) {
return asoc->peer.active_path;
- else {
+ } else {
if (last_sent_to == asoc->peer.retran_path)
sctp_assoc_update_retran_path(asoc);
+
return asoc->peer.retran_path;
}
}
}
/* Should we send a SACK to update our peer? */
-static inline int sctp_peer_needs_update(struct sctp_association *asoc)
+static inline bool sctp_peer_needs_update(struct sctp_association *asoc)
{
struct net *net = sock_net(asoc->base.sk);
switch (asoc->state) {
((asoc->rwnd - asoc->a_rwnd) >= max_t(__u32,
(asoc->base.sk->sk_rcvbuf >> net->sctp.rwnd_upd_shift),
asoc->pathmtu)))
- return 1;
+ return true;
break;
default:
break;
}
- return 0;
+ return false;
}
-/* Increase asoc's rwnd by len and send any window update SACK if needed. */
-void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len)
+/* Update asoc's rwnd for the approximated state in the buffer,
+ * and check whether SACK needs to be sent.
+ */
+void sctp_assoc_rwnd_update(struct sctp_association *asoc, bool update_peer)
{
+ int rx_count;
struct sctp_chunk *sack;
struct timer_list *timer;
- if (asoc->rwnd_over) {
- if (asoc->rwnd_over >= len) {
- asoc->rwnd_over -= len;
- } else {
- asoc->rwnd += (len - asoc->rwnd_over);
- asoc->rwnd_over = 0;
- }
- } else {
- asoc->rwnd += len;
- }
+ if (asoc->ep->rcvbuf_policy)
+ rx_count = atomic_read(&asoc->rmem_alloc);
+ else
+ rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
- /* If we had window pressure, start recovering it
- * once our rwnd had reached the accumulated pressure
- * threshold. The idea is to recover slowly, but up
- * to the initial advertised window.
- */
- if (asoc->rwnd_press && asoc->rwnd >= asoc->rwnd_press) {
- int change = min(asoc->pathmtu, asoc->rwnd_press);
- asoc->rwnd += change;
- asoc->rwnd_press -= change;
- }
+ if ((asoc->base.sk->sk_rcvbuf - rx_count) > 0)
+ asoc->rwnd = (asoc->base.sk->sk_rcvbuf - rx_count) >> 1;
+ else
+ asoc->rwnd = 0;
- pr_debug("%s: asoc:%p rwnd increased by %d to (%u, %u) - %u\n",
- __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
- asoc->a_rwnd);
+ pr_debug("%s: asoc:%p rwnd=%u, rx_count=%d, sk_rcvbuf=%d\n",
+ __func__, asoc, asoc->rwnd, rx_count,
+ asoc->base.sk->sk_rcvbuf);
/* Send a window update SACK if the rwnd has increased by at least the
* minimum of the association's PMTU and half of the receive buffer.
* The algorithm used is similar to the one described in
* Section 4.2.3.3 of RFC 1122.
*/
- if (sctp_peer_needs_update(asoc)) {
+ if (update_peer && sctp_peer_needs_update(asoc)) {
asoc->a_rwnd = asoc->rwnd;
pr_debug("%s: sending window update SACK- asoc:%p rwnd:%u "
}
}
-/* Decrease asoc's rwnd by len. */
-void sctp_assoc_rwnd_decrease(struct sctp_association *asoc, unsigned int len)
-{
- int rx_count;
- int over = 0;
-
- if (unlikely(!asoc->rwnd || asoc->rwnd_over))
- pr_debug("%s: association:%p has asoc->rwnd:%u, "
- "asoc->rwnd_over:%u!\n", __func__, asoc,
- asoc->rwnd, asoc->rwnd_over);
-
- if (asoc->ep->rcvbuf_policy)
- rx_count = atomic_read(&asoc->rmem_alloc);
- else
- rx_count = atomic_read(&asoc->base.sk->sk_rmem_alloc);
-
- /* If we've reached or overflowed our receive buffer, announce
- * a 0 rwnd if rwnd would still be positive. Store the
- * the pottential pressure overflow so that the window can be restored
- * back to original value.
- */
- if (rx_count >= asoc->base.sk->sk_rcvbuf)
- over = 1;
-
- if (asoc->rwnd >= len) {
- asoc->rwnd -= len;
- if (over) {
- asoc->rwnd_press += asoc->rwnd;
- asoc->rwnd = 0;
- }
- } else {
- asoc->rwnd_over = len - asoc->rwnd;
- asoc->rwnd = 0;
- }
-
- pr_debug("%s: asoc:%p rwnd decreased by %d to (%u, %u, %u)\n",
- __func__, asoc, len, asoc->rwnd, asoc->rwnd_over,
- asoc->rwnd_press);
-}
/* Build the bind address list for the association based on info from the
* local endpoint and the remote peer.
projects / ~andy / linux / blobdiff