/*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 2001-2007, by Cisco Systems, Inc. All rights reserved. * Copyright (c) 2008-2012, by Randall Stewart. All rights reserved. * Copyright (c) 2008-2012, by Michael Tuexen. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * a) Redistributions of source code must retain the above copyright notice, * this list of conditions and the following disclaimer. * * b) Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the distribution. * * c) Neither the name of Cisco Systems, Inc. nor the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF * THE POSSIBILITY OF SUCH DAMAGE.
*/
/* * sctp_find_alternate_net() returns a non-NULL pointer as long as there * exists nets, which are not being deleted.
*/ struct sctp_nets *
sctp_find_alternate_net(struct sctp_tcb *stcb, struct sctp_nets *net, int mode)
{ /* Find and return an alternate network if possible */ struct sctp_nets *alt, *mnet, *min_errors_net = NULL , *max_cwnd_net = NULL; bool looped; /* JRS 5/14/07 - Initialize min_errors to an impossible value. */ int min_errors = -1;
uint32_t max_cwnd = 0;
if (stcb->asoc.numnets == 1) { /* No selection can be made. */ return (TAILQ_FIRST(&stcb->asoc.nets));
} /* * JRS 5/14/07 - If mode is set to 2, use the CMT PF find alternate net algorithm. * This algorithm chooses the active destination (not in PF state) with the largest * cwnd value. If all destinations are in PF state, unreachable, or unconfirmed, choose * the destination that is in PF state with the lowest error count. In case of a tie, * choose the destination that was most recently active.
*/ if (mode == 2) {
TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) { /* JRS 5/14/07 - If the destination is unreachable or unconfirmed, skip it. */ if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
(mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) { continue;
} /* * JRS 5/14/07 - If the destination is reachable but in PF state, compare * the error count of the destination to the minimum error count seen thus far. * Store the destination with the lower error count. If the error counts are * equal, store the destination that was most recently active.
*/ if (mnet->dest_state & SCTP_ADDR_PF) { /* * JRS 5/14/07 - If the destination under consideration is the current * destination, work as if the error count is one higher. The * actual error count will not be incremented until later in the * t3 handler.
*/ if (mnet == net) { if (min_errors == -1) {
min_errors = mnet->error_count + 1;
min_errors_net = mnet;
} elseif (mnet->error_count + 1 < min_errors) {
min_errors = mnet->error_count + 1;
min_errors_net = mnet;
} elseif (mnet->error_count + 1 == min_errors
&& mnet->last_active > min_errors_net->last_active) {
min_errors_net = mnet;
min_errors = mnet->error_count + 1;
} continue;
} else { if (min_errors == -1) {
min_errors = mnet->error_count;
min_errors_net = mnet;
} elseif (mnet->error_count < min_errors) {
min_errors = mnet->error_count;
min_errors_net = mnet;
} elseif (mnet->error_count == min_errors
&& mnet->last_active > min_errors_net->last_active) {
min_errors_net = mnet;
min_errors = mnet->error_count;
} continue;
}
} /* * JRS 5/14/07 - If the destination is reachable and not in PF state, compare the * cwnd of the destination to the highest cwnd seen thus far. Store the * destination with the higher cwnd value. If the cwnd values are equal, * randomly choose one of the two destinations.
*/ if (max_cwnd < mnet->cwnd) {
max_cwnd_net = mnet;
max_cwnd = mnet->cwnd;
} elseif (max_cwnd == mnet->cwnd) {
uint32_t rndval;
uint8_t this_random;
if (stcb->asoc.hb_random_idx > 3) {
rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
memcpy(stcb->asoc.hb_random_values, &rndval, sizeof(stcb->asoc.hb_random_values));
this_random = stcb->asoc.hb_random_values[0];
stcb->asoc.hb_random_idx++;
stcb->asoc.hb_ect_randombit = 0;
} else {
this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
stcb->asoc.hb_random_idx++;
stcb->asoc.hb_ect_randombit = 0;
} if (this_random % 2 == 1) {
max_cwnd_net = mnet;
max_cwnd = mnet->cwnd; /* Useless? */
}
}
} if (max_cwnd_net == NULL) { if (min_errors_net == NULL) { return (net);
} return (min_errors_net);
} else { return (max_cwnd_net);
}
} /* JRS 5/14/07 - If mode is set to 1, use the CMT policy for choosing an alternate net. */ elseif (mode == 1) {
TAILQ_FOREACH(mnet, &stcb->asoc.nets, sctp_next) { if (((mnet->dest_state & SCTP_ADDR_REACHABLE) != SCTP_ADDR_REACHABLE) ||
(mnet->dest_state & SCTP_ADDR_UNCONFIRMED)) { /* * will skip ones that are not-reachable or * unconfirmed
*/ continue;
} if (max_cwnd < mnet->cwnd) {
max_cwnd_net = mnet;
max_cwnd = mnet->cwnd;
} elseif (max_cwnd == mnet->cwnd) {
uint32_t rndval;
uint8_t this_random;
if (stcb->asoc.hb_random_idx > 3) {
rndval = sctp_select_initial_TSN(&stcb->sctp_ep->sctp_ep);
memcpy(stcb->asoc.hb_random_values, &rndval, sizeof(stcb->asoc.hb_random_values));
this_random = stcb->asoc.hb_random_values[0];
stcb->asoc.hb_random_idx = 0;
stcb->asoc.hb_ect_randombit = 0;
} else {
this_random = stcb->asoc.hb_random_values[stcb->asoc.hb_random_idx];
stcb->asoc.hb_random_idx++;
stcb->asoc.hb_ect_randombit = 0;
} if (this_random % 2) {
max_cwnd_net = mnet;
max_cwnd = mnet->cwnd;
}
}
} if (max_cwnd_net) { return (max_cwnd_net);
}
} /* Look for an alternate net, which is active. */ if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
alt = TAILQ_NEXT(net, sctp_next);
} else {
alt = TAILQ_FIRST(&stcb->asoc.nets);
}
looped = false; for (;;) { if (alt == NULL) { if (!looped) {
alt = TAILQ_FIRST(&stcb->asoc.nets);
looped = true;
} /* Definitely out of candidates. */ if (alt == NULL) { break;
}
} #ifdefined(__FreeBSD__) && !defined(__Userspace__) if (alt->ro.ro_nh == NULL) { #else if (alt->ro.ro_rt == NULL) { #endif if (alt->ro._s_addr) {
sctp_free_ifa(alt->ro._s_addr);
alt->ro._s_addr = NULL;
}
alt->src_addr_selected = 0;
} if (((alt->dest_state & SCTP_ADDR_REACHABLE) == SCTP_ADDR_REACHABLE) && #ifdefined(__FreeBSD__) && !defined(__Userspace__)
(alt->ro.ro_nh != NULL) && #else
(alt->ro.ro_rt != NULL) && #endif
((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
(alt != net)) { /* Found an alternate net, which is reachable. */ break;
}
alt = TAILQ_NEXT(alt, sctp_next);
}
if (alt == NULL) { /* * In case no active alternate net has been found, look for * an alternate net, which is confirmed.
*/ if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
alt = TAILQ_NEXT(net, sctp_next);
} else {
alt = TAILQ_FIRST(&stcb->asoc.nets);
}
looped = false; for (;;) { if (alt == NULL) { if (!looped) {
alt = TAILQ_FIRST(&stcb->asoc.nets);
looped = true;
} /* Definitely out of candidates. */ if (alt == NULL) { break;
}
} if (((alt->dest_state & SCTP_ADDR_UNCONFIRMED) == 0) &&
(alt != net)) { /* Found an alternate net, which is confirmed. */ break;
}
alt = TAILQ_NEXT(alt, sctp_next);
}
} if (alt == NULL) { /* * In case no confirmed alternate net has been found, just * return net, if it is not being deleted. In the other case * just return the first net.
*/ if ((net != NULL) && ((net->dest_state & SCTP_ADDR_BEING_DELETED) == 0)) {
alt = net;
} if (alt == NULL) {
alt = TAILQ_FIRST(&stcb->asoc.nets);
}
} return (alt);
}
staticvoid
sctp_backoff_on_timeout(struct sctp_tcb *stcb, struct sctp_nets *net, int win_probe, int num_marked, int num_abandoned)
{ if (net->RTO == 0) { if (net->RTO_measured) {
net->RTO = stcb->asoc.minrto;
} else {
net->RTO = stcb->asoc.initial_rto;
}
}
net->RTO <<= 1; if (net->RTO > stcb->asoc.maxrto) {
net->RTO = stcb->asoc.maxrto;
} if ((win_probe == 0) && (num_marked || num_abandoned)) { /* We don't apply penalty to window probe scenarios */ /* JRS - Use the congestion control given in the CC module */
stcb->asoc.cc_functions.sctp_cwnd_update_after_timeout(stcb, net);
}
}
asoc = &stcb->asoc;
TAILQ_FOREACH_SAFE(chk, &asoc->sent_queue, sctp_next, nchk) { if (SCTP_TSN_GE(asoc->last_acked_seq, chk->rec.data.tsn)) {
SCTP_PRINTF("Found chk:%p tsn:%x <= last_acked_seq:%x\n",
(void *)chk, chk->rec.data.tsn, asoc->last_acked_seq); if (chk->sent != SCTP_DATAGRAM_NR_ACKED) { if (asoc->strmout[chk->rec.data.sid].chunks_on_queues > 0) {
asoc->strmout[chk->rec.data.sid].chunks_on_queues--;
}
} if ((asoc->strmout[chk->rec.data.sid].chunks_on_queues == 0) &&
(asoc->strmout[chk->rec.data.sid].state == SCTP_STREAM_RESET_PENDING) &&
TAILQ_EMPTY(&asoc->strmout[chk->rec.data.sid].outqueue)) {
asoc->trigger_reset = 1;
}
TAILQ_REMOVE(&asoc->sent_queue, chk, sctp_next); if (PR_SCTP_ENABLED(chk->flags)) { if (asoc->pr_sctp_cnt != 0)
asoc->pr_sctp_cnt--;
} if (chk->data) { /*sa_ignore NO_NULL_CHK*/
sctp_free_bufspace(stcb, asoc, chk, 1);
sctp_m_freem(chk->data);
chk->data = NULL; if (asoc->prsctp_supported && PR_SCTP_BUF_ENABLED(chk->flags)) {
asoc->sent_queue_cnt_removeable--;
}
}
asoc->sent_queue_cnt--;
sctp_free_a_chunk(stcb, chk, SCTP_SO_NOT_LOCKED);
}
}
SCTP_PRINTF("after recover order is as follows\n");
TAILQ_FOREACH(chk, &asoc->sent_queue, sctp_next) {
SCTP_PRINTF("chk:%p TSN:%x\n", (void *)chk, chk->rec.data.tsn);
}
} #endif
staticint
sctp_mark_all_for_resend(struct sctp_tcb *stcb, struct sctp_nets *net, struct sctp_nets *alt, int window_probe, int *num_marked, int *num_abandoned)
{
/* * Mark all chunks (well not all) that were sent to *net for * retransmission. Move them to alt for there destination as well... * We only mark chunks that have been outstanding long enough to * have received feed-back.
*/ struct sctp_tmit_chunk *chk, *nchk; struct sctp_nets *lnets; struct timeval now, min_wait, tv; int cur_rto; int cnt_abandoned; int audit_tf, num_mk, fir; unsignedint cnt_mk;
uint32_t orig_flight, orig_tf;
uint32_t tsnlast, tsnfirst; #ifndef INVARIANTS int recovery_cnt = 0; #endif
/* none in flight now */
audit_tf = 0;
fir = 0; /* * figure out how long a data chunk must be pending before we can * mark it ..
*/
(void)SCTP_GETTIME_TIMEVAL(&now); /* get cur rto in micro-seconds */
cur_rto = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
cur_rto *= 1000; if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(cur_rto,
stcb->asoc.peers_rwnd,
window_probe,
SCTP_FR_T3_MARK_TIME);
sctp_log_fr(net->flight_size, 0, 0, SCTP_FR_CWND_REPORT);
sctp_log_fr(net->flight_size, net->cwnd, stcb->asoc.total_flight, SCTP_FR_CWND_REPORT);
}
tv.tv_sec = cur_rto / 1000000;
tv.tv_usec = cur_rto % 1000000; #if !(defined(__FreeBSD__) && !defined(__Userspace__))
timersub(&now, &tv, &min_wait); #else
min_wait = now;
timevalsub(&min_wait, &tv); #endif if (min_wait.tv_sec < 0 || min_wait.tv_usec < 0) { /* * if we hit here, we don't have enough seconds on the clock * to account for the RTO. We just let the lower seconds be * the bounds and don't worry about it. This may mean we * will mark a lot more than we should.
*/
min_wait.tv_sec = min_wait.tv_usec = 0;
} if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(cur_rto, (uint32_t)now.tv_sec, now.tv_usec, SCTP_FR_T3_MARK_TIME);
sctp_log_fr(0, (uint32_t)min_wait.tv_sec, min_wait.tv_usec, SCTP_FR_T3_MARK_TIME);
} /* * Our rwnd will be incorrect here since we are not adding back the * cnt * mbuf but we will fix that down below.
*/
orig_flight = net->flight_size;
orig_tf = stcb->asoc.total_flight;
net->fast_retran_ip = 0; /* Now on to each chunk */
cnt_abandoned = 0;
num_mk = cnt_mk = 0;
tsnfirst = tsnlast = 0; #ifndef INVARIANTS
start_again: #endif
TAILQ_FOREACH_SAFE(chk, &stcb->asoc.sent_queue, sctp_next, nchk) { if (SCTP_TSN_GE(stcb->asoc.last_acked_seq, chk->rec.data.tsn)) { /* Strange case our list got out of order? */
SCTP_PRINTF("Our list is out of order? last_acked:%x chk:%x\n",
(unsignedint)stcb->asoc.last_acked_seq, (unsignedint)chk->rec.data.tsn); #ifdef INVARIANTS
panic("last acked >= chk on sent-Q"); #else
recovery_cnt++;
SCTP_PRINTF("Recover attempts a restart cnt:%d\n", recovery_cnt);
sctp_recover_sent_list(stcb); if (recovery_cnt < 10) { goto start_again;
} else {
SCTP_PRINTF("Recovery fails %d times??\n", recovery_cnt);
} #endif
} if ((chk->whoTo == net) && (chk->sent < SCTP_DATAGRAM_ACKED)) { /* * found one to mark: If it is less than * DATAGRAM_ACKED it MUST not be a skipped or marked * TSN but instead one that is either already set * for retransmission OR one that needs * retransmission.
*/
/* validate its been outstanding long enough */ if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(chk->rec.data.tsn,
(uint32_t)chk->sent_rcv_time.tv_sec,
chk->sent_rcv_time.tv_usec,
SCTP_FR_T3_MARK_TIME);
} if ((chk->sent_rcv_time.tv_sec > min_wait.tv_sec) && (window_probe == 0)) { /* * we have reached a chunk that was sent * some seconds past our min.. forget it we * will find no more to send.
*/ if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(0,
(uint32_t)chk->sent_rcv_time.tv_sec,
chk->sent_rcv_time.tv_usec,
SCTP_FR_T3_STOPPED);
} continue;
} elseif ((chk->sent_rcv_time.tv_sec == min_wait.tv_sec) &&
(window_probe == 0)) { /* * we must look at the micro seconds to * know.
*/ if (chk->sent_rcv_time.tv_usec >= min_wait.tv_usec) { /* * ok it was sent after our boundary * time.
*/ continue;
}
} if (stcb->asoc.prsctp_supported && PR_SCTP_TTL_ENABLED(chk->flags)) { /* Is it expired? */ #if !(defined(__FreeBSD__) && !defined(__Userspace__)) if (timercmp(&now, &chk->rec.data.timetodrop, >)) { #else if (timevalcmp(&now, &chk->rec.data.timetodrop, >)) { #endif /* Yes so drop it */ if (chk->data) {
(void)sctp_release_pr_sctp_chunk(stcb,
chk,
1,
SCTP_SO_NOT_LOCKED);
cnt_abandoned++;
} continue;
}
} if (stcb->asoc.prsctp_supported && PR_SCTP_RTX_ENABLED(chk->flags)) { /* Has it been retransmitted tv_sec times? */ if (chk->snd_count > chk->rec.data.timetodrop.tv_sec) { if (chk->data) {
(void)sctp_release_pr_sctp_chunk(stcb,
chk,
1,
SCTP_SO_NOT_LOCKED);
cnt_abandoned++;
} continue;
}
} if (chk->sent < SCTP_DATAGRAM_RESEND) {
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
num_mk++; if (fir == 0) {
fir = 1;
tsnfirst = chk->rec.data.tsn;
}
tsnlast = chk->rec.data.tsn; if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(chk->rec.data.tsn, chk->snd_count,
0, SCTP_FR_T3_MARKED);
}
/* reset the TSN for striking and other FR stuff */
chk->rec.data.doing_fast_retransmit = 0; /* Clear any time so NO RTT is being done */
if (chk->do_rtt) { if (chk->whoTo->rto_needed == 0) {
chk->whoTo->rto_needed = 1;
}
}
chk->do_rtt = 0; if (alt != net) {
sctp_free_remote_addr(chk->whoTo);
chk->no_fr_allowed = 1;
chk->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
} else {
chk->no_fr_allowed = 0; if (TAILQ_EMPTY(&stcb->asoc.send_queue)) {
chk->rec.data.fast_retran_tsn = stcb->asoc.sending_seq;
} else {
chk->rec.data.fast_retran_tsn = (TAILQ_FIRST(&stcb->asoc.send_queue))->rec.data.tsn;
}
} /* CMT: Do not allow FRs on retransmitted TSNs.
*/ if (stcb->asoc.sctp_cmt_on_off > 0) {
chk->no_fr_allowed = 1;
} #ifdef THIS_SHOULD_NOT_BE_DONE
} elseif (chk->sent == SCTP_DATAGRAM_ACKED) { /* remember highest acked one */
could_be_sent = chk; #endif
} if (chk->sent == SCTP_DATAGRAM_RESEND) {
cnt_mk++;
}
} if ((orig_flight - net->flight_size) != (orig_tf - stcb->asoc.total_flight)) { /* we did not subtract the same things? */
audit_tf = 1;
}
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(tsnfirst, tsnlast, num_mk, SCTP_FR_T3_TIMEOUT);
} #ifdef SCTP_DEBUG if (num_mk) {
SCTPDBG(SCTP_DEBUG_TIMER1, "LAST TSN marked was %x\n",
tsnlast);
SCTPDBG(SCTP_DEBUG_TIMER1, "Num marked for retransmission was %d peer-rwd:%u\n",
num_mk,
stcb->asoc.peers_rwnd);
} #endif
*num_marked = num_mk;
*num_abandoned = cnt_abandoned; /* Now check for a ECN Echo that may be stranded And * include the cnt_mk'd to have all resends in the * control queue.
*/
TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) { if (chk->sent == SCTP_DATAGRAM_RESEND) {
cnt_mk++;
} if ((chk->whoTo == net) &&
(chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
sctp_free_remote_addr(chk->whoTo);
chk->whoTo = alt; if (chk->sent != SCTP_DATAGRAM_RESEND) {
chk->sent = SCTP_DATAGRAM_RESEND;
chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
cnt_mk++;
}
atomic_add_int(&alt->ref_count, 1);
}
} #ifdef THIS_SHOULD_NOT_BE_DONE if ((stcb->asoc.sent_queue_retran_cnt == 0) && (could_be_sent)) { /* fix it so we retransmit the highest acked anyway */
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
cnt_mk++;
could_be_sent->sent = SCTP_DATAGRAM_RESEND;
} #endif if (stcb->asoc.sent_queue_retran_cnt != cnt_mk) { #ifdef INVARIANTS
SCTP_PRINTF("Local Audit says there are %d for retran asoc cnt:%d we marked:%d this time\n",
cnt_mk, stcb->asoc.sent_queue_retran_cnt, num_mk); #endif #ifndef SCTP_AUDITING_ENABLED
stcb->asoc.sent_queue_retran_cnt = cnt_mk; #endif
} if (audit_tf) {
SCTPDBG(SCTP_DEBUG_TIMER4, "Audit total flight due to negative value net:%p\n",
(void *)net);
stcb->asoc.total_flight = 0;
stcb->asoc.total_flight_count = 0; /* Clear all networks flight size */
TAILQ_FOREACH(lnets, &stcb->asoc.nets, sctp_next) {
lnets->flight_size = 0;
SCTPDBG(SCTP_DEBUG_TIMER4, "Net:%p c-f cwnd:%d ssthresh:%d\n",
(void *)lnets, lnets->cwnd, lnets->ssthresh);
}
TAILQ_FOREACH(chk, &stcb->asoc.sent_queue, sctp_next) { if (chk->sent < SCTP_DATAGRAM_RESEND) { if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
sctp_misc_ints(SCTP_FLIGHT_LOG_UP,
chk->whoTo->flight_size,
chk->book_size,
(uint32_t)(uintptr_t)chk->whoTo,
chk->rec.data.tsn);
}
sctp_flight_size_increase(chk);
sctp_total_flight_increase(stcb, chk);
}
}
} /* We return 1 if we only have a window probe outstanding */ return (0);
}
int
sctp_t3rxt_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net)
{ struct sctp_nets *alt; int win_probe, num_mk, num_abandoned;
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FR_LOGGING_ENABLE) {
sctp_log_fr(0, 0, 0, SCTP_FR_T3_TIMEOUT);
} if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) { struct sctp_nets *lnet;
TAILQ_FOREACH(lnet, &stcb->asoc.nets, sctp_next) { if (net == lnet) {
sctp_log_cwnd(stcb, lnet, 1, SCTP_CWND_LOG_FROM_T3);
} else {
sctp_log_cwnd(stcb, lnet, 0, SCTP_CWND_LOG_FROM_T3);
}
}
} /* Find an alternate and mark those for retransmission */ if ((stcb->asoc.peers_rwnd == 0) &&
(stcb->asoc.total_flight < net->mtu)) {
SCTP_STAT_INCR(sctps_timowindowprobe);
win_probe = 1;
} else {
win_probe = 0;
}
if (win_probe == 0) { /* We don't do normal threshold management on window probes */ if (sctp_threshold_management(inp, stcb, net,
stcb->asoc.max_send_times)) { /* Association was destroyed */ return (1);
} else { if (net != stcb->asoc.primary_destination) { /* send a immediate HB if our RTO is stale */ struct timeval now;
uint32_t ms_goneby;
(void)SCTP_GETTIME_TIMEVAL(&now); if (net->last_sent_time.tv_sec) {
ms_goneby = (uint32_t)(now.tv_sec - net->last_sent_time.tv_sec) * 1000;
} else {
ms_goneby = 0;
} if ((net->dest_state & SCTP_ADDR_PF) == 0) { if ((ms_goneby > net->RTO) || (net->RTO == 0)) { /* * no recent feed back in an RTO or * more, request a RTT update
*/
sctp_send_hb(stcb, net, SCTP_SO_NOT_LOCKED);
}
}
}
}
} else { /* * For a window probe we don't penalize the net's but only * the association. This may fail it if SACKs are not coming * back. If sack's are coming with rwnd locked at 0, we will * continue to hold things waiting for rwnd to raise
*/ if (sctp_threshold_management(inp, stcb, NULL,
stcb->asoc.max_send_times)) { /* Association was destroyed */ return (1);
}
} if (stcb->asoc.sctp_cmt_on_off > 0) { if (net->pf_threshold < net->failure_threshold) {
alt = sctp_find_alternate_net(stcb, net, 2);
} else { /* * CMT: Using RTX_SSTHRESH policy for CMT. * If CMT is being used, then pick dest with * largest ssthresh for any retransmission.
*/
alt = sctp_find_alternate_net(stcb, net, 1); /* * CUCv2: If a different dest is picked for * the retransmission, then new * (rtx-)pseudo_cumack needs to be tracked * for orig dest. Let CUCv2 track new (rtx-) * pseudo-cumack always.
*/
net->find_pseudo_cumack = 1;
net->find_rtx_pseudo_cumack = 1;
}
} else {
alt = sctp_find_alternate_net(stcb, net, 0);
}
num_mk = 0;
num_abandoned = 0;
(void)sctp_mark_all_for_resend(stcb, net, alt, win_probe,
&num_mk, &num_abandoned); /* FR Loss recovery just ended with the T3. */
stcb->asoc.fast_retran_loss_recovery = 0;
/* CMT FR loss recovery ended with the T3 */
net->fast_retran_loss_recovery = 0; if ((stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins) &&
(net->flight_size == 0)) {
(*stcb->asoc.cc_functions.sctp_cwnd_new_transmission_begins)(stcb, net);
}
/* * setup the sat loss recovery that prevents satellite cwnd advance.
*/
stcb->asoc.sat_t3_loss_recovery = 1;
stcb->asoc.sat_t3_recovery_tsn = stcb->asoc.sending_seq;
/* Backoff the timer and cwnd */
sctp_backoff_on_timeout(stcb, net, win_probe, num_mk, num_abandoned); if (((net->dest_state & SCTP_ADDR_REACHABLE) == 0) ||
(net->dest_state & SCTP_ADDR_PF)) { /* Move all pending over too */
sctp_move_chunks_from_net(stcb, net);
/* Get the address that failed, to * force a new src address selection and * a route allocation.
*/ if (net->ro._s_addr != NULL) {
sctp_free_ifa(net->ro._s_addr);
net->ro._s_addr = NULL;
}
net->src_addr_selected = 0;
/* Force a route allocation too */ #ifdefined(__FreeBSD__) && !defined(__Userspace__)
RO_NHFREE(&net->ro); #else if (net->ro.ro_rt != NULL) {
RTFREE(net->ro.ro_rt);
net->ro.ro_rt = NULL;
} #endif
/* Was it our primary? */ if ((stcb->asoc.primary_destination == net) && (alt != net)) { /* * Yes, note it as such and find an alternate note: * this means HB code must use this to resent the * primary if it goes active AND if someone does a * change-primary then this flag must be cleared * from any net structures.
*/ if (stcb->asoc.alternate != NULL) {
sctp_free_remote_addr(stcb->asoc.alternate);
}
stcb->asoc.alternate = alt;
atomic_add_int(&stcb->asoc.alternate->ref_count, 1);
}
} /* * Special case for cookie-echo'ed case, we don't do output but must * await the COOKIE-ACK before retransmission
*/ if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) { /* * Here we just reset the timer and start again since we * have not established the asoc
*/
sctp_timer_start(SCTP_TIMER_TYPE_SEND, inp, stcb, net); return (0);
} if (stcb->asoc.prsctp_supported) { struct sctp_tmit_chunk *lchk;
lchk = sctp_try_advance_peer_ack_point(stcb, &stcb->asoc); /* C3. See if we need to send a Fwd-TSN */ if (SCTP_TSN_GT(stcb->asoc.advanced_peer_ack_point, stcb->asoc.last_acked_seq)) {
send_forward_tsn(stcb, &stcb->asoc); for (; lchk != NULL; lchk = TAILQ_NEXT(lchk, sctp_next)) { if (lchk->whoTo != NULL) { break;
}
} if (lchk != NULL) { /* Assure a timer is up */
sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, lchk->whoTo);
}
}
} if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_MONITOR_ENABLE) {
sctp_log_cwnd(stcb, net, net->cwnd, SCTP_CWND_LOG_FROM_RTX);
} return (0);
}
int
sctp_t1init_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net)
{ /* bump the thresholds */ if (stcb->asoc.delayed_connection) { /* * special hook for delayed connection. The library did NOT * complete the rest of its sends.
*/
stcb->asoc.delayed_connection = 0;
sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED); return (0);
} if (SCTP_GET_STATE(stcb) != SCTP_STATE_COOKIE_WAIT) { return (0);
} if (sctp_threshold_management(inp, stcb, net,
stcb->asoc.max_init_times)) { /* Association was destroyed */ return (1);
}
stcb->asoc.dropped_special_cnt = 0;
sctp_backoff_on_timeout(stcb, stcb->asoc.primary_destination, 1, 0, 0); if (stcb->asoc.initial_init_rto_max < net->RTO) {
net->RTO = stcb->asoc.initial_init_rto_max;
} if (stcb->asoc.numnets > 1) { /* If we have more than one addr use it */ struct sctp_nets *alt;
alt = sctp_find_alternate_net(stcb, stcb->asoc.primary_destination, 0); if (alt != stcb->asoc.primary_destination) {
sctp_move_chunks_from_net(stcb, stcb->asoc.primary_destination);
stcb->asoc.primary_destination = alt;
}
} /* Send out a new init */
sctp_send_initiate(inp, stcb, SCTP_SO_NOT_LOCKED); return (0);
}
/* * For cookie and asconf we actually need to find and mark for resend, then * increment the resend counter (after all the threshold management stuff of * course).
*/ int
sctp_cookie_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net SCTP_UNUSED)
{ struct sctp_nets *alt; struct sctp_tmit_chunk *cookie;
/* first before all else we must find the cookie */
TAILQ_FOREACH(cookie, &stcb->asoc.control_send_queue, sctp_next) { if (cookie->rec.chunk_id.id == SCTP_COOKIE_ECHO) { break;
}
} if (cookie == NULL) { if (SCTP_GET_STATE(stcb) == SCTP_STATE_COOKIE_ECHOED) { /* FOOBAR! */ struct mbuf *op_err;
op_err = sctp_generate_cause(SCTP_BASE_SYSCTL(sctp_diag_info_code), "Cookie timer expired, but no cookie");
inp->last_abort_code = SCTP_FROM_SCTP_TIMER + SCTP_LOC_3;
sctp_abort_an_association(inp, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
} else { #ifdef INVARIANTS
panic("Cookie timer expires in wrong state?"); #else
SCTP_PRINTF("Strange in state %d not cookie-echoed yet c-e timer expires?\n", SCTP_GET_STATE(stcb)); return (0); #endif
} return (0);
} /* Ok we found the cookie, threshold management next */ if (sctp_threshold_management(inp, stcb, cookie->whoTo,
stcb->asoc.max_init_times)) { /* Assoc is over */ return (1);
} /* * Cleared threshold management, now lets backoff the address * and select an alternate
*/
stcb->asoc.dropped_special_cnt = 0;
sctp_backoff_on_timeout(stcb, cookie->whoTo, 1, 0, 0);
alt = sctp_find_alternate_net(stcb, cookie->whoTo, 0); if (alt != cookie->whoTo) {
sctp_free_remote_addr(cookie->whoTo);
cookie->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
} /* Now mark the retran info */ if (cookie->sent != SCTP_DATAGRAM_RESEND) {
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
}
cookie->sent = SCTP_DATAGRAM_RESEND;
cookie->flags |= CHUNK_FLAGS_FRAGMENT_OK; /* * Now call the output routine to kick out the cookie again, Note we * don't mark any chunks for retran so that FR will need to kick in * to move these (or a send timer).
*/ return (0);
}
if (stcb->asoc.stream_reset_outstanding == 0) { return (0);
} /* find the existing STRRESET, we use the seq number we sent out on */
(void)sctp_find_stream_reset(stcb, stcb->asoc.str_reset_seq_out, &strrst); if (strrst == NULL) { return (0);
}
net = strrst->whoTo; /* do threshold management */ if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) { /* Assoc is over */ return (1);
} /* * Cleared threshold management, now lets backoff the address * and select an alternate
*/
sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
alt = sctp_find_alternate_net(stcb, net, 0);
strrst->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
/* See if a ECN Echo is also stranded */
TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) { if ((chk->whoTo == net) &&
(chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
sctp_free_remote_addr(chk->whoTo); if (chk->sent != SCTP_DATAGRAM_RESEND) {
chk->sent = SCTP_DATAGRAM_RESEND;
chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
}
chk->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
}
} if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) { /* * If the address went un-reachable, we need to move to * alternates for ALL chk's in queue
*/
sctp_move_chunks_from_net(stcb, net);
}
sctp_free_remote_addr(net);
/* mark the retran info */ if (strrst->sent != SCTP_DATAGRAM_RESEND)
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
strrst->sent = SCTP_DATAGRAM_RESEND;
strrst->flags |= CHUNK_FLAGS_FRAGMENT_OK;
/* is this a first send, or a retransmission? */ if (TAILQ_EMPTY(&stcb->asoc.asconf_send_queue)) { /* compose a new ASCONF chunk and send it */
sctp_send_asconf(stcb, net, SCTP_ADDR_NOT_LOCKED);
} else { /* * Retransmission of the existing ASCONF is needed
*/
/* find the existing ASCONF */
asconf = TAILQ_FIRST(&stcb->asoc.asconf_send_queue); if (asconf == NULL) { return (0);
}
net = asconf->whoTo; /* do threshold management */ if (sctp_threshold_management(inp, stcb, net,
stcb->asoc.max_send_times)) { /* Assoc is over */ return (1);
} if (asconf->snd_count > stcb->asoc.max_send_times) { /* * Something is rotten: our peer is not responding to * ASCONFs but apparently is to other chunks. i.e. it * is not properly handling the chunk type upper bits. * Mark this peer as ASCONF incapable and cleanup.
*/
SCTPDBG(SCTP_DEBUG_TIMER1, "asconf_timer: Peer has not responded to our repeated ASCONFs\n");
sctp_asconf_cleanup(stcb); return (0);
} /* * cleared threshold management, so now backoff the net and * select an alternate
*/
sctp_backoff_on_timeout(stcb, net, 1, 0, 0);
alt = sctp_find_alternate_net(stcb, net, 0); if (asconf->whoTo != alt) {
asconf->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
}
/* See if an ECN Echo is also stranded */
TAILQ_FOREACH(chk, &stcb->asoc.control_send_queue, sctp_next) { if ((chk->whoTo == net) &&
(chk->rec.chunk_id.id == SCTP_ECN_ECHO)) {
sctp_free_remote_addr(chk->whoTo);
chk->whoTo = alt; if (chk->sent != SCTP_DATAGRAM_RESEND) {
chk->sent = SCTP_DATAGRAM_RESEND;
chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
}
atomic_add_int(&alt->ref_count, 1);
}
}
TAILQ_FOREACH(chk, &stcb->asoc.asconf_send_queue, sctp_next) { if (chk->whoTo != alt) {
sctp_free_remote_addr(chk->whoTo);
chk->whoTo = alt;
atomic_add_int(&alt->ref_count, 1);
} if (asconf->sent != SCTP_DATAGRAM_RESEND && chk->sent != SCTP_DATAGRAM_UNSENT)
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
chk->sent = SCTP_DATAGRAM_RESEND;
chk->flags |= CHUNK_FLAGS_FRAGMENT_OK;
} if ((net->dest_state & SCTP_ADDR_REACHABLE) == 0) { /* * If the address went un-reachable, we need to move * to the alternate for ALL chunks in queue
*/
sctp_move_chunks_from_net(stcb, net);
}
sctp_free_remote_addr(net);
/* mark the retran info */ if (asconf->sent != SCTP_DATAGRAM_RESEND)
sctp_ucount_incr(stcb->asoc.sent_queue_retran_cnt);
asconf->sent = SCTP_DATAGRAM_RESEND;
asconf->flags |= CHUNK_FLAGS_FRAGMENT_OK;
/* send another ASCONF if any and we can do */
sctp_send_asconf(stcb, alt, SCTP_ADDR_NOT_LOCKED);
} return (0);
}
/* * For the shutdown and shutdown-ack, we do not keep one around on the * control queue. This means we must generate a new one and call the general * chunk output routine, AFTER having done threshold management. * It is assumed that net is non-NULL.
*/ int
sctp_shutdown_timer(struct sctp_inpcb *inp, struct sctp_tcb *stcb, struct sctp_nets *net)
{ struct sctp_nets *alt;
/* first threshold management */ if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) { /* Assoc is over */ return (1);
}
sctp_backoff_on_timeout(stcb, net, 1, 0, 0); /* second select an alternative */
alt = sctp_find_alternate_net(stcb, net, 0);
/* third generate a shutdown into the queue for out net */
sctp_send_shutdown(stcb, alt);
/* first threshold management */ if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) { /* Assoc is over */ return (1);
}
sctp_backoff_on_timeout(stcb, net, 1, 0, 0); /* second select an alternative */
alt = sctp_find_alternate_net(stcb, net, 0);
/* third generate a shutdown into the queue for out net */
sctp_send_shutdown_ack(stcb, alt);
staticvoid
sctp_audit_stream_queues_for_size(struct sctp_inpcb *inp, struct sctp_tcb *stcb)
{ struct sctp_stream_queue_pending *sp; unsignedint i, chks_in_queue = 0; int being_filled = 0;
KASSERT(inp != NULL, ("inp is NULL"));
KASSERT(stcb != NULL, ("stcb is NULL"));
SCTP_TCB_LOCK_ASSERT(stcb);
KASSERT(TAILQ_EMPTY(&stcb->asoc.send_queue), ("send_queue not empty"));
KASSERT(TAILQ_EMPTY(&stcb->asoc.sent_queue), ("sent_queue not empty"));
if (stcb->asoc.sent_queue_retran_cnt) {
SCTP_PRINTF("Hmm, sent_queue_retran_cnt is non-zero %d\n",
stcb->asoc.sent_queue_retran_cnt);
stcb->asoc.sent_queue_retran_cnt = 0;
} if (stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) { /* No stream scheduler information, initialize scheduler */
stcb->asoc.ss_functions.sctp_ss_init(stcb, &stcb->asoc); if (!stcb->asoc.ss_functions.sctp_ss_is_empty(stcb, &stcb->asoc)) { /* yep, we lost a stream or two */
SCTP_PRINTF("Found additional streams NOT managed by scheduler, corrected\n");
} else { /* no streams lost */
stcb->asoc.total_output_queue_size = 0;
}
} /* Check to see if some data queued, if so report it */ for (i = 0; i < stcb->asoc.streamoutcnt; i++) { if (!TAILQ_EMPTY(&stcb->asoc.strmout[i].outqueue)) {
TAILQ_FOREACH(sp, &stcb->asoc.strmout[i].outqueue, next) { if (sp->msg_is_complete)
being_filled++;
chks_in_queue++;
}
}
} if (chks_in_queue != stcb->asoc.stream_queue_cnt) {
SCTP_PRINTF("Hmm, stream queue cnt at %d I counted %d in stream out wheel\n",
stcb->asoc.stream_queue_cnt, chks_in_queue);
} if (chks_in_queue) { /* call the output queue function */
sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_T3, SCTP_SO_NOT_LOCKED); if ((TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
(TAILQ_EMPTY(&stcb->asoc.sent_queue))) { /* * Probably should go in and make it go back through * and add fragments allowed
*/ if (being_filled == 0) {
SCTP_PRINTF("Still nothing moved %d chunks are stuck\n",
chks_in_queue);
}
}
} else {
SCTP_PRINTF("Found no chunks on any queue tot:%lu\n",
(u_long)stcb->asoc.total_output_queue_size);
stcb->asoc.total_output_queue_size = 0;
}
}
net_was_pf = (net->dest_state & SCTP_ADDR_PF) != 0; if (net->hb_responded == 0) { if (net->ro._s_addr != NULL) { /* Invalidate the src address if we did not get * a response last time.
*/
sctp_free_ifa(net->ro._s_addr);
net->ro._s_addr = NULL;
net->src_addr_selected = 0;
}
sctp_backoff_on_timeout(stcb, net, 1, 0, 0); if (sctp_threshold_management(inp, stcb, net, stcb->asoc.max_send_times)) { /* Assoc is over */ return (1);
}
} /* Zero PBA, if it needs it */ if (net->partial_bytes_acked > 0) {
net->partial_bytes_acked = 0;
} if ((stcb->asoc.total_output_queue_size > 0) &&
(TAILQ_EMPTY(&stcb->asoc.send_queue)) &&
(TAILQ_EMPTY(&stcb->asoc.sent_queue))) {
sctp_audit_stream_queues_for_size(inp, stcb);
} if ((((net->dest_state & SCTP_ADDR_NOHB) == 0) ||
(net->dest_state & SCTP_ADDR_UNCONFIRMED)) &&
(net_was_pf || ((net->dest_state & SCTP_ADDR_PF) == 0))) { /* When moving to PF during threshold management, a HB has been
queued in that routine. */
uint32_t ms_gone_by;
(void)SCTP_GETTIME_TIMEVAL(&tn); if (stcb->asoc.sctp_autoclose_ticks > 0 &&
sctp_is_feature_on(inp, SCTP_PCB_FLAGS_AUTOCLOSE)) { /* Auto close is on */
asoc = &stcb->asoc; /* pick the time to use */ if (asoc->time_last_rcvd.tv_sec >
asoc->time_last_sent.tv_sec) {
tim_touse = &asoc->time_last_rcvd;
} else {
tim_touse = &asoc->time_last_sent;
} /* Now has long enough transpired to autoclose? */
ticks_gone_by = sctp_secs_to_ticks((uint32_t)(tn.tv_sec - tim_touse->tv_sec)); if (ticks_gone_by >= asoc->sctp_autoclose_ticks) { /* * autoclose time has hit, call the output routine, * which should do nothing just to be SURE we don't * have hanging data. We can then safely check the * queues and know that we are clear to send * shutdown
*/
sctp_chunk_output(inp, stcb, SCTP_OUTPUT_FROM_AUTOCLOSE_TMR, SCTP_SO_NOT_LOCKED); /* Are we clean? */ if (TAILQ_EMPTY(&asoc->send_queue) &&
TAILQ_EMPTY(&asoc->sent_queue)) { /* * there is nothing queued to send, so I'm * done...
*/ if (SCTP_GET_STATE(stcb) != SCTP_STATE_SHUTDOWN_SENT) { /* only send SHUTDOWN 1st time thru */ struct sctp_nets *net;
if ((SCTP_GET_STATE(stcb) == SCTP_STATE_OPEN) ||
(SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) {
SCTP_STAT_DECR_GAUGE32(sctps_currestab);
}
SCTP_SET_STATE(stcb, SCTP_STATE_SHUTDOWN_SENT);
sctp_stop_timers_for_shutdown(stcb); if (stcb->asoc.alternate) {
net = stcb->asoc.alternate;
} else {
net = stcb->asoc.primary_destination;
}
sctp_send_shutdown(stcb, net);
sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
stcb->sctp_ep, stcb, net);
sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
stcb->sctp_ep, stcb, NULL);
}
}
} else { /* * No auto close at this time, reset t-o to check * later
*/
uint32_t tmp;
/* fool the timer startup to use the time left */
tmp = asoc->sctp_autoclose_ticks;
asoc->sctp_autoclose_ticks -= ticks_gone_by;
sctp_timer_start(SCTP_TIMER_TYPE_AUTOCLOSE, inp, stcb, NULL); /* restore the real tick value */
asoc->sctp_autoclose_ticks = tmp;
}
}
}
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