diff options
Diffstat (limited to 'net/sctp/associola.c')
| -rw-r--r-- | net/sctp/associola.c | 279 |
1 files changed, 107 insertions, 172 deletions
diff --git a/net/sctp/associola.c b/net/sctp/associola.c index 31ed008c8e1..ee13d28d39d 100644 --- a/net/sctp/associola.c +++ b/net/sctp/associola.c @@ -22,9 +22,8 @@ * 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): @@ -90,14 +89,12 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a /* 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 @@ -110,8 +107,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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. */ @@ -132,18 +127,15 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a */ 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 @@ -152,7 +144,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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; @@ -172,11 +163,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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 @@ -189,25 +175,15 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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); @@ -218,7 +194,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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 * @@ -237,7 +212,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a /* 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 * @@ -251,20 +225,15 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a * 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); @@ -276,12 +245,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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. */ @@ -297,9 +260,6 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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); @@ -307,9 +267,7 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a 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, @@ -994,17 +952,13 @@ int sctp_cmp_addr_exact(const union sctp_addr *ss1, */ 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); } /* @@ -1265,7 +1219,7 @@ void sctp_assoc_update(struct sctp_association *asoc, } } - /* 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); @@ -1285,78 +1239,107 @@ void sctp_assoc_update(struct sctp_association *asoc, } /* 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; } } @@ -1393,7 +1376,7 @@ void sctp_assoc_sync_pmtu(struct sock *sk, struct sctp_association *asoc) } /* 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) { @@ -1405,52 +1388,43 @@ static inline int sctp_peer_needs_update(struct sctp_association *asoc) ((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 " @@ -1472,45 +1446,6 @@ void sctp_assoc_rwnd_increase(struct sctp_association *asoc, unsigned int len) } } -/* 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. |