void
sctp_express_handle_sack(struct sctp_tcb *stcb, uint32_t cumack,
uint32_t rwnd, int *abort_now, int ecne_seen)
{
struct sctp_nets *net;
struct sctp_association *asoc;
struct sctp_tmit_chunk *tp1, *tp2;
uint32_t old_rwnd;
int win_probe_recovery = 0;
int win_probe_recovered = 0;
int j, done_once = 0;
int rto_ok = 1;
uint32_t send_s;
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_LOG_SACK_ARRIVALS_ENABLE) {
sctp_misc_ints(SCTP_SACK_LOG_EXPRESS, cumack,
rwnd, stcb->asoc.last_acked_seq, stcb->asoc.peers_rwnd);
}
SCTP_TCB_LOCK_ASSERT(stcb);
#ifdef SCTP_ASOCLOG_OF_TSNS
stcb->asoc.cumack_log[stcb->asoc.cumack_log_at] = cumack;
stcb->asoc.cumack_log_at++;
if (stcb->asoc.cumack_log_at > SCTP_TSN_LOG_SIZE) {
stcb->asoc.cumack_log_at = 0;
}
#endif
asoc = &stcb->asoc;
old_rwnd = asoc->peers_rwnd;
if (SCTP_TSN_GT(asoc->last_acked_seq, cumack)) {
/* old ack */
return;
} else if (asoc->last_acked_seq == cumack) {
/* Window update sack */
asoc->peers_rwnd = sctp_sbspace_sub(rwnd,
(uint32_t) (asoc->total_flight + (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh))));
if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
/* SWS sender side engages */
asoc->peers_rwnd = 0;
}
if (asoc->peers_rwnd > old_rwnd) {
goto again;
}
return;
}
/* First setup for CC stuff */
TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
if (SCTP_TSN_GT(cumack, net->cwr_window_tsn)) {
/* Drag along the window_tsn for cwr's */
net->cwr_window_tsn = cumack;
}
net->prev_cwnd = net->cwnd;
net->net_ack = 0;
net->net_ack2 = 0;
/*
* CMT: Reset CUC and Fast recovery algo variables before
* SACK processing
*/
net->new_pseudo_cumack = 0;
net->will_exit_fast_recovery = 0;
if (stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack) {
(*stcb->asoc.cc_functions.sctp_cwnd_prepare_net_for_sack)(stcb, net);
}
}
if (!TAILQ_EMPTY(&asoc->sent_queue)) {
tp1 = TAILQ_LAST(&asoc->sent_queue,
sctpchunk_listhead);
send_s = tp1->rec.data.tsn + 1;
} else {
send_s = asoc->sending_seq;
}
if (SCTP_TSN_GE(cumack, send_s)) {
struct mbuf *op_err;
char msg[SCTP_DIAG_INFO_LEN];
*abort_now = 1;
/* XXX */
SCTP_SNPRINTF(msg, sizeof(msg),
"Cum ack %8.8x greater or equal than TSN %8.8x",
cumack, send_s);
op_err = sctp_generate_cause(SCTP_CAUSE_PROTOCOL_VIOLATION, msg);
stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_25;
sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
return;
}
asoc->this_sack_highest_gap = cumack;
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_THRESHOLD_LOGGING) {
sctp_misc_ints(SCTP_THRESHOLD_CLEAR,
stcb->asoc.overall_error_count,
0,
SCTP_FROM_SCTP_INDATA,
__LINE__);
}
stcb->asoc.overall_error_count = 0;
if (SCTP_TSN_GT(cumack, asoc->last_acked_seq)) {
/* process the new consecutive TSN first */
TAILQ_FOREACH_SAFE(tp1, &asoc->sent_queue, sctp_next, tp2) {
if (SCTP_TSN_GE(cumack, tp1->rec.data.tsn)) {
if (tp1->sent == SCTP_DATAGRAM_UNSENT) {
SCTP_PRINTF("Warning, an unsent is now acked?\n");
}
if (tp1->sent < SCTP_DATAGRAM_ACKED) {
/*
* If it is less than ACKED, it is
* now no-longer in flight. Higher
* values may occur during marking
*/
if (tp1->sent < SCTP_DATAGRAM_RESEND) {
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_FLIGHT_LOGGING_ENABLE) {
sctp_misc_ints(SCTP_FLIGHT_LOG_DOWN_CA,
tp1->whoTo->flight_size,
tp1->book_size,
(uint32_t)(uintptr_t)tp1->whoTo,
tp1->rec.data.tsn);
}
sctp_flight_size_decrease(tp1);
if (stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged) {
(*stcb->asoc.cc_functions.sctp_cwnd_update_tsn_acknowledged)(tp1->whoTo,
tp1);
}
/* sa_ignore NO_NULL_CHK */
sctp_total_flight_decrease(stcb, tp1);
}
tp1->whoTo->net_ack += tp1->send_size;
if (tp1->snd_count < 2) {
/*
* True non-retransmitted
* chunk
*/
tp1->whoTo->net_ack2 +=
tp1->send_size;
/* update RTO too? */
if (tp1->do_rtt) {
if (rto_ok &&
sctp_calculate_rto(stcb,
&stcb->asoc,
tp1->whoTo,
&tp1->sent_rcv_time,
SCTP_RTT_FROM_DATA)) {
rto_ok = 0;
}
if (tp1->whoTo->rto_needed == 0) {
tp1->whoTo->rto_needed = 1;
}
tp1->do_rtt = 0;
}
}
/*
* CMT: CUCv2 algorithm. From the
* cumack'd TSNs, for each TSN being
* acked for the first time, set the
* following variables for the
* corresp destination.
* new_pseudo_cumack will trigger a
* cwnd update.
* find_(rtx_)pseudo_cumack will
* trigger search for the next
* expected (rtx-)pseudo-cumack.
*/
tp1->whoTo->new_pseudo_cumack = 1;
tp1->whoTo->find_pseudo_cumack = 1;
tp1->whoTo->find_rtx_pseudo_cumack = 1;
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_CWND_LOGGING_ENABLE) {
/* sa_ignore NO_NULL_CHK */
sctp_log_cwnd(stcb, tp1->whoTo, tp1->rec.data.tsn, SCTP_CWND_LOG_FROM_SACK);
}
}
if (tp1->sent == SCTP_DATAGRAM_RESEND) {
sctp_ucount_decr(asoc->sent_queue_retran_cnt);
}
if (tp1->rec.data.chunk_was_revoked) {
/* deflate the cwnd */
tp1->whoTo->cwnd -= tp1->book_size;
tp1->rec.data.chunk_was_revoked = 0;
}
if (tp1->sent != SCTP_DATAGRAM_NR_ACKED) {
if (asoc->strmout[tp1->rec.data.sid].chunks_on_queues > 0) {
asoc->strmout[tp1->rec.data.sid].chunks_on_queues--;
#ifdef INVARIANTS
} else {
panic("No chunks on the queues for sid %u.", tp1->rec.data.sid);
#endif
}
}
if ((asoc->strmout[tp1->rec.data.sid].chunks_on_queues == 0) &&
(asoc->strmout[tp1->rec.data.sid].state == SCTP_STREAM_RESET_PENDING) &&
TAILQ_EMPTY(&asoc->strmout[tp1->rec.data.sid].outqueue)) {
asoc->trigger_reset = 1;
}
TAILQ_REMOVE(&asoc->sent_queue, tp1, sctp_next);
if (tp1->data) {
/* sa_ignore NO_NULL_CHK */
sctp_free_bufspace(stcb, asoc, tp1, 1);
sctp_m_freem(tp1->data);
tp1->data = NULL;
}
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_SACK_LOGGING_ENABLE) {
sctp_log_sack(asoc->last_acked_seq,
cumack,
tp1->rec.data.tsn,
0,
0,
SCTP_LOG_FREE_SENT);
}
asoc->sent_queue_cnt--;
sctp_free_a_chunk(stcb, tp1, SCTP_SO_NOT_LOCKED);
} else {
break;
}
}
}
#if defined(__Userspace__)
if (stcb->sctp_ep->recv_callback) {
if (stcb->sctp_socket) {
uint32_t inqueue_bytes, sb_free_now;
struct sctp_inpcb *inp;
inp = stcb->sctp_ep;
inqueue_bytes = stcb->asoc.total_output_queue_size - (stcb->asoc.chunks_on_out_queue * sizeof(struct sctp_data_chunk));
sb_free_now = SCTP_SB_LIMIT_SND(stcb->sctp_socket) - (inqueue_bytes + stcb->asoc.sb_send_resv);
/* check if the amount free in the send socket buffer crossed the threshold */
if (inp->send_callback &&
(((inp->send_sb_threshold > 0) &&
(sb_free_now >= inp->send_sb_threshold) &&
(stcb->asoc.chunks_on_out_queue <= SCTP_BASE_SYSCTL(sctp_max_chunks_on_queue))) ||
(inp->send_sb_threshold == 0))) {
atomic_add_int(&stcb->asoc.refcnt, 1);
SCTP_TCB_UNLOCK(stcb);
inp->send_callback(stcb->sctp_socket, sb_free_now, inp->ulp_info);
SCTP_TCB_LOCK(stcb);
atomic_subtract_int(&stcb->asoc.refcnt, 1);
}
}
} else if (stcb->sctp_socket) {
#else
/* sa_ignore NO_NULL_CHK */
if (stcb->sctp_socket) {
#endif
#if defined(__APPLE__) && !defined(__Userspace__)
struct socket *so;
#endif
SOCKBUF_LOCK(&stcb->sctp_socket->so_snd);
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
/* sa_ignore NO_NULL_CHK */
sctp_wakeup_log(stcb, 1, SCTP_WAKESND_FROM_SACK);
}
#if defined(__APPLE__) && !defined(__Userspace__)
so = SCTP_INP_SO(stcb->sctp_ep);
atomic_add_int(&stcb->asoc.refcnt, 1);
SCTP_TCB_UNLOCK(stcb);
SCTP_SOCKET_LOCK(so, 1);
SCTP_TCB_LOCK(stcb);
atomic_subtract_int(&stcb->asoc.refcnt, 1);
if (stcb->asoc.state & SCTP_STATE_CLOSED_SOCKET) {
/* assoc was freed while we were unlocked */
SCTP_SOCKET_UNLOCK(so, 1);
return;
}
#endif
sctp_sowwakeup_locked(stcb->sctp_ep, stcb->sctp_socket);
#if defined(__APPLE__) && !defined(__Userspace__)
SCTP_SOCKET_UNLOCK(so, 1);
#endif
} else {
if (SCTP_BASE_SYSCTL(sctp_logging_level) & SCTP_WAKE_LOGGING_ENABLE) {
sctp_wakeup_log(stcb, 1, SCTP_NOWAKE_FROM_SACK);
}
}
/* JRS - Use the congestion control given in the CC module */
if ((asoc->last_acked_seq != cumack) && (ecne_seen == 0)) {
TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
if (net->net_ack2 > 0) {
/*
* Karn's rule applies to clearing error count, this
* is optional.
*/
net->error_count = 0;
if (!(net->dest_state & SCTP_ADDR_REACHABLE)) {
/* addr came good */
net->dest_state |= SCTP_ADDR_REACHABLE;
sctp_ulp_notify(SCTP_NOTIFY_INTERFACE_UP, stcb,
0, (void *)net, SCTP_SO_NOT_LOCKED);
}
if (net == stcb->asoc.primary_destination) {
if (stcb->asoc.alternate) {
/* release the alternate, primary is good */
sctp_free_remote_addr(stcb->asoc.alternate);
stcb->asoc.alternate = NULL;
}
}
if (net->dest_state & SCTP_ADDR_PF) {
net->dest_state &= ~SCTP_ADDR_PF;
sctp_timer_stop(SCTP_TIMER_TYPE_HEARTBEAT,
stcb->sctp_ep, stcb, net,
SCTP_FROM_SCTP_INDATA + SCTP_LOC_26);
sctp_timer_start(SCTP_TIMER_TYPE_HEARTBEAT, stcb->sctp_ep, stcb, net);
asoc->cc_functions.sctp_cwnd_update_exit_pf(stcb, net);
/* Done with this net */
net->net_ack = 0;
}
/* restore any doubled timers */
net->RTO = (net->lastsa >> SCTP_RTT_SHIFT) + net->lastsv;
if (net->RTO < stcb->asoc.minrto) {
net->RTO = stcb->asoc.minrto;
}
if (net->RTO > stcb->asoc.maxrto) {
net->RTO = stcb->asoc.maxrto;
}
}
}
asoc->cc_functions.sctp_cwnd_update_after_sack(stcb, asoc, 1, 0, 0);
}
asoc->last_acked_seq = cumack;
if (TAILQ_EMPTY(&asoc->sent_queue)) {
/* nothing left in-flight */
TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
net->flight_size = 0;
net->partial_bytes_acked = 0;
}
asoc->total_flight = 0;
asoc->total_flight_count = 0;
}
/* RWND update */
asoc->peers_rwnd = sctp_sbspace_sub(rwnd,
(uint32_t) (asoc->total_flight + (asoc->total_flight_count * SCTP_BASE_SYSCTL(sctp_peer_chunk_oh))));
if (asoc->peers_rwnd < stcb->sctp_ep->sctp_ep.sctp_sws_sender) {
/* SWS sender side engages */
asoc->peers_rwnd = 0;
}
if (asoc->peers_rwnd > old_rwnd) {
win_probe_recovery = 1;
}
/* Now assure a timer where data is queued at */
again:
j = 0;
TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
if (win_probe_recovery && (net->window_probe)) {
win_probe_recovered = 1;
/*
* Find first chunk that was used with window probe
* and clear the sent
*/
/* sa_ignore FREED_MEMORY */
TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
if (tp1->window_probe) {
/* move back to data send queue */
sctp_window_probe_recovery(stcb, asoc, tp1);
break;
}
}
}
if (net->flight_size) {
j++;
sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, net);
if (net->window_probe) {
net->window_probe = 0;
}
} else {
if (net->window_probe) {
/* In window probes we must assure a timer is still running there */
net->window_probe = 0;
if (!SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
sctp_timer_start(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep, stcb, net);
}
} else if (SCTP_OS_TIMER_PENDING(&net->rxt_timer.timer)) {
sctp_timer_stop(SCTP_TIMER_TYPE_SEND, stcb->sctp_ep,
stcb, net,
SCTP_FROM_SCTP_INDATA + SCTP_LOC_27);
}
}
}
if ((j == 0) &&
(!TAILQ_EMPTY(&asoc->sent_queue)) &&
(asoc->sent_queue_retran_cnt == 0) &&
(win_probe_recovered == 0) &&
(done_once == 0)) {
/* huh, this should not happen unless all packets
* are PR-SCTP and marked to skip of course.
*/
if (sctp_fs_audit(asoc)) {
TAILQ_FOREACH(net, &asoc->nets, sctp_next) {
net->flight_size = 0;
}
asoc->total_flight = 0;
asoc->total_flight_count = 0;
asoc->sent_queue_retran_cnt = 0;
TAILQ_FOREACH(tp1, &asoc->sent_queue, sctp_next) {
if (tp1->sent < SCTP_DATAGRAM_RESEND) {
sctp_flight_size_increase(tp1);
sctp_total_flight_increase(stcb, tp1);
} else if (tp1->sent == SCTP_DATAGRAM_RESEND) {
sctp_ucount_incr(asoc->sent_queue_retran_cnt);
}
}
}
done_once = 1;
goto again;
}
/**********************************/
/* Now what about shutdown issues */
/**********************************/
if (TAILQ_EMPTY(&asoc->send_queue) && TAILQ_EMPTY(&asoc->sent_queue)) {
/* nothing left on sendqueue.. consider done */
/* clean up */
if ((asoc->stream_queue_cnt == 1) &&
((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
(SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) &&
((*asoc->ss_functions.sctp_ss_is_user_msgs_incomplete)(stcb, asoc))) {
SCTP_ADD_SUBSTATE(stcb, SCTP_STATE_PARTIAL_MSG_LEFT);
}
if (((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) ||
(SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED)) &&
(asoc->stream_queue_cnt == 1) &&
(asoc->state & SCTP_STATE_PARTIAL_MSG_LEFT)) {
struct mbuf *op_err;
*abort_now = 1;
/* XXX */
op_err = sctp_generate_cause(SCTP_CAUSE_USER_INITIATED_ABT, "");
stcb->sctp_ep->last_abort_code = SCTP_FROM_SCTP_INDATA + SCTP_LOC_28;
sctp_abort_an_association(stcb->sctp_ep, stcb, op_err, false, SCTP_SO_NOT_LOCKED);
return;
}
if ((asoc->state & SCTP_STATE_SHUTDOWN_PENDING) &&
(asoc->stream_queue_cnt == 0)) {
struct sctp_nets *netp;
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 (asoc->alternate) {
netp = asoc->alternate;
} else {
netp = asoc->primary_destination;
}
sctp_send_shutdown(stcb, netp);
sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWN,
stcb->sctp_ep, stcb, netp);
sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNGUARD,
stcb->sctp_ep, stcb, NULL);
} else if ((SCTP_GET_STATE(stcb) == SCTP_STATE_SHUTDOWN_RECEIVED) &&
(asoc->stream_queue_cnt == 0)) {
struct sctp_nets *netp;
SCTP_STAT_DECR_GAUGE32(sctps_currestab);
SCTP_SET_STATE(stcb, SCTP_STATE_SHUTDOWN_ACK_SENT);
sctp_stop_timers_for_shutdown(stcb);
if (asoc->alternate) {
netp = asoc->alternate;
} else {
netp = asoc->primary_destination;
}
sctp_send_shutdown_ack(stcb, netp);
sctp_timer_start(SCTP_TIMER_TYPE_SHUTDOWNACK,
stcb->sctp_ep, stcb, netp);
}
}
/*********************************************/
/* Here we perform PR-SCTP procedures */
/* (section 4.2) */
/*********************************************/
/* C1. update advancedPeerAckPoint */
if (SCTP_TSN_GT(cumack, asoc->advanced_peer_ack_point)) {
asoc->advanced_peer_ack_point = cumack;
}
/* PR-Sctp issues need to be addressed too */
if ((asoc->prsctp_supported) && (asoc->pr_sctp_cnt > 0)) {
struct sctp_tmit_chunk *lchk;
uint32_t old_adv_peer_ack_point;
old_adv_peer_ack_point = asoc->advanced_peer_ack_point;
lchk = sctp_try_advance_peer_ack_point(stcb, asoc);
/* C3. See if we need to send a Fwd-TSN */
if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, cumack)) {
/*
* ISSUE with ECN, see FWD-TSN processing.
*/
if (SCTP_TSN_GT(asoc->advanced_peer_ack_point, old_adv_peer_ack_point)) {
send_forward_tsn(stcb, asoc);
} else if (lchk) {
/* try to FR fwd-tsn's that get lost too */
if (lchk->rec.data.fwd_tsn_cnt >= 3) {
send_forward_tsn(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_SACK_RWND_LOGGING_ENABLE) {
sctp_misc_ints(SCTP_SACK_RWND_UPDATE,
rwnd,
stcb->asoc.peers_rwnd,
stcb->asoc.total_flight,
stcb->asoc.total_output_queue_size);
}
}
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