* or the rcv_nxt at last ack sent instead of rcv_nxt since that's the
* peer's reference when computing our receive window.
*
- * This accepts only segments within the window.
+ * This:
+ * seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd) && seq_geq (seq, tc->rcv_las)
+ * however, is too strict when we have retransmits. Instead we just check that
+ * the seq is not beyond the right edge and that the end of the segment is not
+ * less than the left edge.
+ *
+ * N.B. rcv_nxt and rcv_wnd are both updated in this node if acks are sent, so
+ * use rcv_nxt in the right edge window test instead of rcv_las.
+ *
*/
always_inline u8
tcp_segment_in_rcv_wnd (tcp_connection_t * tc, u32 seq, u32 end_seq)
{
- return seq_leq (end_seq, tc->rcv_las + tc->rcv_wnd)
- && seq_geq (seq, tc->rcv_nxt);
+ return (seq_geq (end_seq, tc->rcv_las)
+ && seq_leq (seq, tc->rcv_nxt + tc->rcv_wnd));
}
-void
+/**
+ * Parse TCP header options.
+ *
+ * @param th TCP header
+ * @param to TCP options data structure to be populated
+ * @return -1 if parsing failed
+ */
+int
tcp_options_parse (tcp_header_t * th, tcp_options_t * to)
{
const u8 *data;
if (kind == TCP_OPTION_EOL)
break;
else if (kind == TCP_OPTION_NOOP)
- opt_len = 1;
+ {
+ opt_len = 1;
+ continue;
+ }
else
{
/* broken options */
if (opts_len < 2)
- break;
+ return -1;
opt_len = data[1];
/* weird option length */
if (opt_len < 2 || opt_len > opts_len)
- break;
+ return -1;
}
/* Parse options */
continue;
}
}
+ return 0;
}
+/**
+ * RFC1323: Check against wrapped sequence numbers (PAWS). If we have
+ * timestamp to echo and it's less than tsval_recent, drop segment
+ * but still send an ACK in order to retain TCP's mechanism for detecting
+ * and recovering from half-open connections
+ *
+ * Or at least that's what the theory says. It seems that this might not work
+ * very well with packet reordering and fast retransmit. XXX
+ */
always_inline int
tcp_segment_check_paws (tcp_connection_t * tc)
{
- /* XXX normally test for timestamp should be lt instead of leq, but for
- * local testing this is not enough */
return tcp_opts_tstamp (&tc->opt) && tc->tsval_recent
&& timestamp_lt (tc->opt.tsval, tc->tsval_recent);
}
+/**
+ * Update tsval recent
+ */
+always_inline void
+tcp_update_timestamp (tcp_connection_t * tc, u32 seq, u32 seq_end)
+{
+ /*
+ * RFC1323: If Last.ACK.sent falls within the range of sequence numbers
+ * of an incoming segment:
+ * SEG.SEQ <= Last.ACK.sent < SEG.SEQ + SEG.LEN
+ * then the TSval from the segment is copied to TS.Recent;
+ * otherwise, the TSval is ignored.
+ */
+ if (tcp_opts_tstamp (&tc->opt) && tc->tsval_recent
+ && seq_leq (seq, tc->rcv_las) && seq_leq (tc->rcv_las, seq_end))
+ {
+ tc->tsval_recent = tc->opt.tsval;
+ tc->tsval_recent_age = tcp_time_now ();
+ }
+}
+
/**
* Validate incoming segment as per RFC793 p. 69 and RFC1323 p. 19
*
tcp_segment_validate (vlib_main_t * vm, tcp_connection_t * tc0,
vlib_buffer_t * b0, tcp_header_t * th0, u32 * next0)
{
- u8 paws_failed;
-
if (PREDICT_FALSE (!tcp_ack (th0) && !tcp_rst (th0) && !tcp_syn (th0)))
return -1;
- tcp_options_parse (th0, &tc0->opt);
+ if (PREDICT_FALSE (tcp_options_parse (th0, &tc0->opt)))
+ {
+ return -1;
+ }
- /* RFC1323: Check against wrapped sequence numbers (PAWS). If we have
- * timestamp to echo and it's less than tsval_recent, drop segment
- * but still send an ACK in order to retain TCP's mechanism for detecting
- * and recovering from half-open connections */
- paws_failed = tcp_segment_check_paws (tc0);
- if (paws_failed)
+ if (tcp_segment_check_paws (tc0))
{
clib_warning ("paws failed");
+ TCP_EVT_DBG (TCP_EVT_PAWS_FAIL, tc0, vnet_buffer (b0)->tcp.seq_number,
+ vnet_buffer (b0)->tcp.seq_end);
/* If it just so happens that a segment updates tsval_recent for a
* segment over 24 days old, invalidate tsval_recent. */
{
/* Age isn't reset until we get a valid tsval (bsd inspired) */
tc0->tsval_recent = 0;
+ clib_warning ("paws failed - really old segment. REALLY?");
}
else
{
{
tcp_make_ack (tc0, b0);
*next0 = tcp_next_output (tc0->c_is_ip4);
+ TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0);
return -1;
}
}
if (!tcp_segment_in_rcv_wnd (tc0, vnet_buffer (b0)->tcp.seq_number,
vnet_buffer (b0)->tcp.seq_end))
{
- if (!tcp_rst (th0))
+ /* If our window is 0 and the packet is in sequence, let it pass
+ * through for ack processing. It should be dropped later.*/
+ if (tc0->rcv_wnd == 0
+ && tc0->rcv_nxt == vnet_buffer (b0)->tcp.seq_number)
{
- /* Send dup ack */
- tcp_make_ack (tc0, b0);
- *next0 = tcp_next_output (tc0->c_is_ip4);
+ /* TODO Should segment be tagged? */
+ }
+ else
+ {
+ /* If not RST, send dup ack */
+ if (!tcp_rst (th0))
+ {
+ tcp_make_ack (tc0, b0);
+ *next0 = tcp_next_output (tc0->c_is_ip4);
+ TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc0);
+ }
+ return -1;
}
- return -1;
}
/* 2nd: check the RST bit */
if (tcp_rst (th0))
{
- /* Notify session that connection has been reset. Switch
- * state to closed and await for session to do the cleanup. */
- stream_session_reset_notify (&tc0->connection);
- tc0->state = TCP_STATE_CLOSED;
+ tcp_connection_reset (tc0);
return -1;
}
return -1;
}
- /* If PAWS passed and segment in window, save timestamp */
- if (!paws_failed)
- {
- tc0->tsval_recent = tc0->opt.tsval;
- tc0->tsval_recent_age = tcp_time_now ();
- }
+ /* If segment in window, save timestamp */
+ tcp_update_timestamp (tc0, vnet_buffer (b0)->tcp.seq_number,
+ vnet_buffer (b0)->tcp.seq_end);
return 0;
}
/* XXX Drop in RTT results in RTTVAR increase and bigger RTO.
* The increase should be bound */
- tc->rttvar += (clib_abs (err) - tc->rttvar) >> 2;
+ tc->rttvar += ((int) clib_abs (err) - (int) tc->rttvar) >> 2;
}
else
{
/* First measurement. */
tc->srtt = mrtt;
- tc->rttvar = mrtt << 1;
+ tc->rttvar = mrtt >> 1;
}
}
tcp_update_rtt (tcp_connection_t * tc, u32 ack)
{
u32 mrtt = 0;
+ u8 rtx_acked;
+
+ /* Determine if only rtx bytes are acked. TODO fast retransmit */
+ rtx_acked = tc->rto_boff && (tc->bytes_acked <= tc->snd_mss);
/* Karn's rule, part 1. Don't use retransmitted segments to estimate
* RTT because they're ambiguous. */
- if (tc->rtt_seq && seq_gt (ack, tc->rtt_seq) && !tc->rto_boff)
+ if (tc->rtt_ts && seq_geq (ack, tc->rtt_seq) && !rtx_acked)
{
mrtt = tcp_time_now () - tc->rtt_ts;
- tc->rtt_seq = 0;
}
-
/* As per RFC7323 TSecr can be used for RTTM only if the segment advances
* snd_una, i.e., the left side of the send window:
* seq_lt (tc->snd_una, ack). Note: last condition could be dropped, we don't
mrtt = tcp_time_now () - tc->opt.tsecr;
}
+ /* Allow measuring of a new RTT */
+ tc->rtt_ts = 0;
+
+ /* If ACK moves left side of the wnd make sure boff is 0, even if mrtt is
+ * not valid */
+ if (tc->bytes_acked)
+ tc->rto_boff = 0;
+
/* Ignore dubious measurements */
if (mrtt == 0 || mrtt > TCP_RTT_MAX)
return 0;
tcp_estimate_rtt (tc, mrtt);
-
tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
- return 1;
+ return 0;
}
/**
stream_session_dequeue_drop (&tc->connection, tc->bytes_acked);
/* Update rtt and rto */
- if (tcp_update_rtt (tc, ack))
- {
- /* Good ACK received and valid RTT, make sure retransmit backoff is 0 */
- tc->rto_boff = 0;
- }
+ tcp_update_rtt (tc, ack);
}
-/** Check if dupack as per RFC5681 Sec. 2 */
+/**
+ * Check if dupack as per RFC5681 Sec. 2
+ *
+ * This works only if called before updating snd_wnd.
+ * */
always_inline u8
tcp_ack_is_dupack (tcp_connection_t * tc, vlib_buffer_t * b, u32 new_snd_wnd)
{
}
sack_scoreboard_hole_t *
-scoreboard_insert_hole (sack_scoreboard_t * sb, sack_scoreboard_hole_t * prev,
+scoreboard_insert_hole (sack_scoreboard_t * sb, u32 prev_index,
u32 start, u32 end)
{
- sack_scoreboard_hole_t *hole, *next;
+ sack_scoreboard_hole_t *hole, *next, *prev;
u32 hole_index;
pool_get (sb->holes, hole);
hole->end = end;
hole_index = hole - sb->holes;
+ prev = scoreboard_get_hole (sb, prev_index);
if (prev)
{
hole->prev = prev - sb->holes;
return hole;
}
-static void
+void
tcp_rcv_sacks (tcp_connection_t * tc, u32 ack)
{
sack_scoreboard_t *sb = &tc->sack_sb;
sack_block_t *blk, tmp;
- sack_scoreboard_hole_t *hole, *next_hole;
- u32 blk_index = 0;
+ sack_scoreboard_hole_t *hole, *next_hole, *last_hole, *new_hole;
+ u32 blk_index = 0, old_sacked_bytes, delivered_bytes, hole_index;
int i, j;
- if (!tcp_opts_sack (tc) && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
+ sb->last_sacked_bytes = 0;
+ sb->snd_una_adv = 0;
+ old_sacked_bytes = sb->sacked_bytes;
+ delivered_bytes = 0;
+
+ if (!tcp_opts_sack (&tc->opt) && sb->head == TCP_INVALID_SACK_HOLE_INDEX)
return;
/* Remove invalid blocks */
- vec_foreach (blk, tc->opt.sacks)
- {
- if (seq_lt (blk->start, blk->end)
- && seq_gt (blk->start, tc->snd_una)
- && seq_gt (blk->start, ack) && seq_lt (blk->end, tc->snd_nxt))
- continue;
-
- vec_del1 (tc->opt.sacks, blk - tc->opt.sacks);
- }
+ blk = tc->opt.sacks;
+ while (blk < vec_end (tc->opt.sacks))
+ {
+ if (seq_lt (blk->start, blk->end)
+ && seq_gt (blk->start, tc->snd_una)
+ && seq_gt (blk->start, ack) && seq_leq (blk->end, tc->snd_nxt))
+ {
+ blk++;
+ continue;
+ }
+ vec_del1 (tc->opt.sacks, blk - tc->opt.sacks);
+ }
/* Add block for cumulative ack */
if (seq_gt (ack, tc->snd_una))
/* Make sure blocks are ordered */
for (i = 0; i < vec_len (tc->opt.sacks); i++)
- for (j = i; j < vec_len (tc->opt.sacks); j++)
+ for (j = i + 1; j < vec_len (tc->opt.sacks); j++)
if (seq_lt (tc->opt.sacks[j].start, tc->opt.sacks[i].start))
{
tmp = tc->opt.sacks[i];
tc->opt.sacks[j] = tmp;
}
- /* If no holes, insert the first that covers all outstanding bytes */
if (sb->head == TCP_INVALID_SACK_HOLE_INDEX)
{
- scoreboard_insert_hole (sb, 0, tc->snd_una, tc->snd_una_max);
+ /* If no holes, insert the first that covers all outstanding bytes */
+ last_hole = scoreboard_insert_hole (sb, TCP_INVALID_SACK_HOLE_INDEX,
+ tc->snd_una, tc->snd_una_max);
+ sb->tail = scoreboard_hole_index (sb, last_hole);
+ tmp = tc->opt.sacks[vec_len (tc->opt.sacks) - 1];
+ sb->max_byte_sacked = tmp.end;
+ }
+ else
+ {
+ /* If we have holes but snd_una_max is beyond the last hole, update
+ * last hole end */
+ tmp = tc->opt.sacks[vec_len (tc->opt.sacks) - 1];
+ last_hole = scoreboard_last_hole (sb);
+ if (seq_gt (tc->snd_una_max, sb->max_byte_sacked)
+ && seq_gt (tc->snd_una_max, last_hole->end))
+ last_hole->end = tc->snd_una_max;
}
/* Walk the holes with the SACK blocks */
next_hole = scoreboard_next_hole (sb, hole);
/* Byte accounting */
- if (seq_lt (hole->end, ack))
+ if (seq_leq (hole->end, ack))
{
- /* Bytes lost because snd wnd left edge advances */
- if (seq_lt (next_hole->start, ack))
- sb->sacked_bytes -= next_hole->start - hole->end;
+ /* Bytes lost because snd_wnd left edge advances */
+ if (next_hole && seq_leq (next_hole->start, ack))
+ delivered_bytes += next_hole->start - hole->end;
else
- sb->sacked_bytes -= ack - hole->end;
+ delivered_bytes += ack - hole->end;
}
else
{
sb->sacked_bytes += scoreboard_hole_bytes (hole);
}
+ /* About to remove last hole */
+ if (hole == last_hole)
+ {
+ sb->tail = hole->prev;
+ last_hole = scoreboard_last_hole (sb);
+ /* keep track of max byte sacked for when the last hole
+ * is acked */
+ if (seq_gt (hole->end, sb->max_byte_sacked))
+ sb->max_byte_sacked = hole->end;
+ }
+
+ /* snd_una needs to be advanced */
+ if (blk->end == ack && seq_geq (ack, hole->end))
+ {
+ if (next_hole && seq_lt (ack, next_hole->start))
+ {
+ sb->snd_una_adv = next_hole->start - ack;
+
+ /* all these can be delivered */
+ delivered_bytes += sb->snd_una_adv;
+ }
+ else if (!next_hole)
+ {
+ sb->snd_una_adv = sb->max_byte_sacked - ack;
+ delivered_bytes += sb->snd_una_adv;
+ }
+ }
+
scoreboard_remove_hole (sb, hole);
hole = next_hole;
}
- /* Partial overlap */
+ /* Partial 'head' overlap */
else
{
- sb->sacked_bytes += blk->end - hole->start;
- hole->start = blk->end;
+ if (seq_gt (blk->end, hole->start))
+ {
+ sb->sacked_bytes += blk->end - hole->start;
+ hole->start = blk->end;
+ }
blk_index++;
}
}
else
{
/* Hole must be split */
- if (seq_leq (blk->end, hole->end))
+ if (seq_lt (blk->end, hole->end))
{
sb->sacked_bytes += blk->end - blk->start;
- scoreboard_insert_hole (sb, hole, blk->end, hole->end);
- hole->end = blk->start - 1;
+ hole_index = scoreboard_hole_index (sb, hole);
+ new_hole = scoreboard_insert_hole (sb, hole_index, blk->end,
+ hole->end);
+
+ /* Pool might've moved */
+ hole = scoreboard_get_hole (sb, hole_index);
+ hole->end = blk->start;
+
+ /* New or split of tail */
+ if ((last_hole->end == new_hole->end)
+ || seq_lt (last_hole->end, new_hole->start))
+ {
+ last_hole = new_hole;
+ sb->tail = scoreboard_hole_index (sb, new_hole);
+ }
+
blk_index++;
+ hole = scoreboard_next_hole (sb, hole);
}
else
{
- sb->sacked_bytes += hole->end - blk->start + 1;
- hole->end = blk->start - 1;
+ sb->sacked_bytes += hole->end - blk->start;
+ hole->end = blk->start;
hole = scoreboard_next_hole (sb, hole);
}
}
}
+
+ sb->last_sacked_bytes = sb->sacked_bytes - old_sacked_bytes;
+ sb->sacked_bytes -= delivered_bytes;
}
/** Update snd_wnd
static void
tcp_update_snd_wnd (tcp_connection_t * tc, u32 seq, u32 ack, u32 snd_wnd)
{
- if (tc->snd_wl1 < seq || (tc->snd_wl1 == seq && tc->snd_wl2 <= ack))
+ if (seq_lt (tc->snd_wl1, seq)
+ || (tc->snd_wl1 == seq && seq_leq (tc->snd_wl2, ack)))
{
tc->snd_wnd = snd_wnd;
tc->snd_wl1 = seq;
tc->snd_wl2 = ack;
+ TCP_EVT_DBG (TCP_EVT_SND_WND, tc);
+
+ /* Set probe timer if we just got 0 wnd */
+ if (tc->snd_wnd < tc->snd_mss)
+ {
+ if (!tcp_timer_is_active (tc, TCP_TIMER_PERSIST))
+ tcp_persist_timer_set (tc);
+ }
+ else
+ tcp_persist_timer_reset (tc);
}
}
-static void
+void
tcp_cc_congestion (tcp_connection_t * tc)
{
+ tc->snd_congestion = tc->snd_nxt;
tc->cc_algo->congestion (tc);
+ TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 4);
}
-static void
+void
tcp_cc_recover (tcp_connection_t * tc)
{
- if (tcp_in_fastrecovery (tc))
- {
- tc->cc_algo->recovered (tc);
- tcp_recovery_off (tc);
- }
- else if (tcp_in_recovery (tc))
- {
- tcp_recovery_off (tc);
- tc->cwnd = tcp_loss_wnd (tc);
- }
+ /* TODO: check if time to recover was small. It might be that RTO popped
+ * too soon.
+ */
+
+ tc->cc_algo->recovered (tc);
+
+ tc->rtx_bytes = 0;
+ tc->rcv_dupacks = 0;
+ tc->snd_nxt = tc->snd_una;
+
+ tc->cc_algo->rcv_ack (tc);
+ tc->tsecr_last_ack = tc->opt.tsecr;
+
+ tcp_cong_recovery_off (tc);
+
+ TCP_EVT_DBG (TCP_EVT_CC_EVT, tc, 3);
}
static void
-tcp_cc_rcv_ack (tcp_connection_t * tc)
+tcp_cc_rcv_ack (tcp_connection_t * tc, vlib_buffer_t * b)
{
u8 partial_ack;
+ u32 bytes_advanced;
- if (tcp_in_recovery (tc))
+ if (tcp_in_fastrecovery (tc))
{
- partial_ack = seq_lt (tc->snd_una, tc->snd_una_max);
+ partial_ack = seq_lt (tc->snd_una, tc->snd_congestion);
if (!partial_ack)
{
/* Clear retransmitted bytes. */
- tc->rtx_bytes = 0;
tcp_cc_recover (tc);
}
else
{
+ TCP_EVT_DBG (TCP_EVT_CC_PACK, tc);
+
/* Clear retransmitted bytes. XXX should we clear all? */
tc->rtx_bytes = 0;
+
tc->cc_algo->rcv_cong_ack (tc, TCP_CC_PARTIALACK);
- /* Retransmit first unacked segment */
- tcp_retransmit_first_unacked (tc);
+ /* In case snd_nxt is still in the past and output tries to
+ * shove some new bytes */
+ tc->snd_nxt = tc->snd_una_max;
+
+ /* XXX need proper RFC6675 support */
+ if (tc->sack_sb.last_sacked_bytes && !tcp_in_recovery (tc))
+ {
+ tcp_fast_retransmit (tc);
+ }
+ else
+ {
+ /* Retransmit first unacked segment */
+ tcp_retransmit_first_unacked (tc);
+ }
}
}
else
{
tc->cc_algo->rcv_ack (tc);
+ tc->tsecr_last_ack = tc->opt.tsecr;
+ tc->rcv_dupacks = 0;
+ if (tcp_in_recovery (tc))
+ {
+ bytes_advanced = tc->bytes_acked + tc->sack_sb.snd_una_adv;
+ tc->rtx_bytes -= clib_min (bytes_advanced, tc->rtx_bytes);
+ tc->rto = clib_min (tc->srtt + (tc->rttvar << 2), TCP_RTO_MAX);
+ if (seq_geq (tc->snd_una, tc->snd_congestion))
+ {
+ tc->rtx_bytes = 0;
+ tcp_recovery_off (tc);
+ }
+ }
}
-
- tc->rcv_dupacks = 0;
- tc->tsecr_last_ack = tc->opt.tsecr;
}
static void
tcp_cc_rcv_dupack (tcp_connection_t * tc, u32 ack)
{
- ASSERT (tc->snd_una == ack);
+// ASSERT (seq_geq(tc->snd_una, ack));
tc->rcv_dupacks++;
if (tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
{
u32 new_snd_wnd;
- /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) then send an
- * ACK, drop the segment, and return */
+ /* If the ACK acks something not yet sent (SEG.ACK > SND.NXT) */
if (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_nxt))
{
- tcp_make_ack (tc, b);
- *next = tcp_next_output (tc->c_is_ip4);
- *error = TCP_ERROR_ACK_INVALID;
- return -1;
+ /* If we have outstanding data and this is within the window, accept it,
+ * probably retransmit has timed out. Otherwise ACK segment and then
+ * drop it */
+ if (seq_gt (vnet_buffer (b)->tcp.ack_number, tc->snd_una_max))
+ {
+ tcp_make_ack (tc, b);
+ *next = tcp_next_output (tc->c_is_ip4);
+ *error = TCP_ERROR_ACK_INVALID;
+ TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 0,
+ vnet_buffer (b)->tcp.ack_number);
+ return -1;
+ }
+
+ TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 2,
+ vnet_buffer (b)->tcp.ack_number);
+
+ tc->snd_nxt = vnet_buffer (b)->tcp.ack_number;
+ *error = TCP_ERROR_ACK_FUTURE;
}
- /* If old ACK, discard */
+ /* If old ACK, probably it's an old dupack */
if (seq_lt (vnet_buffer (b)->tcp.ack_number, tc->snd_una))
{
*error = TCP_ERROR_ACK_OLD;
- return -1;
+ TCP_EVT_DBG (TCP_EVT_ACK_RCV_ERR, tc, 1,
+ vnet_buffer (b)->tcp.ack_number);
+ if (tcp_in_fastrecovery (tc) && tc->rcv_dupacks == TCP_DUPACK_THRESHOLD)
+ {
+ TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc);
+ tcp_cc_rcv_dupack (tc, vnet_buffer (b)->tcp.ack_number);
+ }
+ /* Don't drop yet */
+ return 0;
}
if (tcp_opts_sack_permitted (&tc->opt))
if (tcp_ack_is_dupack (tc, b, new_snd_wnd))
{
+ TCP_EVT_DBG (TCP_EVT_DUPACK_RCVD, tc, 1);
tcp_cc_rcv_dupack (tc, vnet_buffer (b)->tcp.ack_number);
*error = TCP_ERROR_ACK_DUP;
return -1;
}
- /* Valid ACK */
+ /*
+ * Valid ACK
+ */
+
tc->bytes_acked = vnet_buffer (b)->tcp.ack_number - tc->snd_una;
- tc->snd_una = vnet_buffer (b)->tcp.ack_number;
+ tc->snd_una = vnet_buffer (b)->tcp.ack_number + tc->sack_sb.snd_una_adv;
- /* Dequeue ACKed packet and update RTT */
+ /* Dequeue ACKed data and update RTT */
tcp_dequeue_acked (tc, vnet_buffer (b)->tcp.ack_number);
-
tcp_update_snd_wnd (tc, vnet_buffer (b)->tcp.seq_number,
vnet_buffer (b)->tcp.ack_number, new_snd_wnd);
- /* Updates congestion control (slow start/congestion avoidance) */
- tcp_cc_rcv_ack (tc);
+ /* If some of our sent bytes have been acked, update cc and retransmit
+ * timer. */
+ if (tc->bytes_acked)
+ {
+ TCP_EVT_DBG (TCP_EVT_ACK_RCVD, tc);
+
+ /* Updates congestion control (slow start/congestion avoidance) */
+ tcp_cc_rcv_ack (tc, b);
- /* If everything has been acked, stop retransmit timer
- * otherwise update */
- if (tc->snd_una == tc->snd_una_max)
- tcp_timer_reset (tc, TCP_TIMER_RETRANSMIT);
- else
- tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, tc->rto);
+ /* If everything has been acked, stop retransmit timer
+ * otherwise update. */
+ if (tc->snd_una == tc->snd_una_max)
+ tcp_retransmit_timer_reset (tc);
+ else
+ tcp_retransmit_timer_update (tc);
+ }
return 0;
}
* @param start Start sequence number of the newest SACK block
* @param end End sequence of the newest SACK block
*/
-static void
+void
tcp_update_sack_list (tcp_connection_t * tc, u32 start, u32 end)
{
- sack_block_t *new_list = 0, block;
- u32 n_elts;
+ sack_block_t *new_list = 0, *block = 0;
int i;
- u8 new_head = 0;
/* If the first segment is ooo add it to the list. Last write might've moved
* rcv_nxt over the first segment. */
if (seq_lt (tc->rcv_nxt, start))
{
- block.start = start;
- block.end = end;
- vec_add1 (new_list, block);
- new_head = 1;
+ vec_add2 (new_list, block, 1);
+ block->start = start;
+ block->end = end;
}
/* Find the blocks still worth keeping. */
for (i = 0; i < vec_len (tc->snd_sacks); i++)
{
- /* Discard if:
- * 1) rcv_nxt advanced beyond current block OR
- * 2) Segment overlapped by the first segment, i.e., it has been merged
- * into it.*/
- if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt)
- || seq_leq (tc->snd_sacks[i].start, end))
+ /* Discard if rcv_nxt advanced beyond current block */
+ if (seq_leq (tc->snd_sacks[i].start, tc->rcv_nxt))
continue;
- /* Save subsequent segments to new SACK list. */
- n_elts = clib_min (vec_len (tc->snd_sacks) - i,
- TCP_MAX_SACK_BLOCKS - new_head);
- vec_insert_elts (new_list, &tc->snd_sacks[i], n_elts, new_head);
- break;
+ /* Merge or drop if segment overlapped by the new segment */
+ if (block && (seq_geq (tc->snd_sacks[i].end, new_list[0].start)
+ && seq_leq (tc->snd_sacks[i].start, new_list[0].end)))
+ {
+ if (seq_lt (tc->snd_sacks[i].start, new_list[0].start))
+ new_list[0].start = tc->snd_sacks[i].start;
+ if (seq_lt (new_list[0].end, tc->snd_sacks[i].end))
+ new_list[0].end = tc->snd_sacks[i].end;
+ continue;
+ }
+
+ /* Save to new SACK list if we have space. */
+ if (vec_len (new_list) < TCP_MAX_SACK_BLOCKS)
+ {
+ vec_add1 (new_list, tc->snd_sacks[i]);
+ }
}
+ ASSERT (vec_len (new_list) <= TCP_MAX_SACK_BLOCKS);
+
/* Replace old vector with new one */
vec_free (tc->snd_sacks);
tc->snd_sacks = new_list;
}
/** Enqueue data for delivery to application */
-always_inline u32
+always_inline int
tcp_session_enqueue_data (tcp_connection_t * tc, vlib_buffer_t * b,
u16 data_len)
{
return TCP_ERROR_PURE_ACK;
}
- written = stream_session_enqueue_data (&tc->connection,
- vlib_buffer_get_current (b),
- data_len, 1 /* queue event */ );
+ written = stream_session_enqueue_data (&tc->connection, b, 0,
+ 1 /* queue event */ , 1);
+
+ TCP_EVT_DBG (TCP_EVT_INPUT, tc, 0, data_len, written);
/* Update rcv_nxt */
if (PREDICT_TRUE (written == data_len))
/* Send ACK confirming the update */
tc->flags |= TCP_CONN_SNDACK;
+ }
+ else if (written > 0)
+ {
+ /* We've written something but FIFO is probably full now */
+ tc->rcv_nxt += written;
- /* Update SACK list if need be */
- if (tcp_opts_sack_permitted (&tc->opt))
- {
- /* Remove SACK blocks that have been delivered */
- tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
- }
+ /* Depending on how fast the app is, all remaining buffers in burst will
+ * not be enqueued. Inform peer */
+ tc->flags |= TCP_CONN_SNDACK;
+
+ return TCP_ERROR_PARTIALLY_ENQUEUED;
}
else
{
- ASSERT (0);
+ tc->flags |= TCP_CONN_SNDACK;
return TCP_ERROR_FIFO_FULL;
}
+ /* Update SACK list if need be */
+ if (tcp_opts_sack_permitted (&tc->opt))
+ {
+ /* Remove SACK blocks that have been delivered */
+ tcp_update_sack_list (tc, tc->rcv_nxt, tc->rcv_nxt);
+ }
+
return TCP_ERROR_ENQUEUED;
}
/** Enqueue out-of-order data */
-always_inline u32
+always_inline int
tcp_session_enqueue_ooo (tcp_connection_t * tc, vlib_buffer_t * b,
u16 data_len)
{
stream_session_t *s0;
- u32 offset, seq;
+ int rv;
- s0 = stream_session_get (tc->c_s_index, tc->c_thread_index);
- seq = vnet_buffer (b)->tcp.seq_number;
- offset = seq - tc->rcv_nxt;
+ /* Pure ACK. Do nothing */
+ if (PREDICT_FALSE (data_len == 0))
+ {
+ return TCP_ERROR_PURE_ACK;
+ }
- if (svm_fifo_enqueue_with_offset (s0->server_rx_fifo, s0->pid, offset,
- data_len, vlib_buffer_get_current (b)))
- return TCP_ERROR_FIFO_FULL;
+ /* Enqueue out-of-order data with absolute offset */
+ rv = stream_session_enqueue_data (&tc->connection, b,
+ vnet_buffer (b)->tcp.seq_number,
+ 0 /* queue event */ , 0);
+
+ /* Nothing written */
+ if (rv)
+ {
+ TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, 0);
+ return TCP_ERROR_FIFO_FULL;
+ }
+
+ TCP_EVT_DBG (TCP_EVT_INPUT, tc, 1, data_len, data_len);
/* Update SACK list if in use */
if (tcp_opts_sack_permitted (&tc->opt))
ooo_segment_t *newest;
u32 start, end;
+ s0 = stream_session_get (tc->c_s_index, tc->c_thread_index);
+
/* Get the newest segment from the fifo */
newest = svm_fifo_newest_ooo_segment (s0->server_rx_fifo);
- start = tc->rcv_nxt + ooo_segment_offset (s0->server_rx_fifo, newest);
- end = tc->rcv_nxt + ooo_segment_end_offset (s0->server_rx_fifo, newest);
+ start = ooo_segment_offset (s0->server_rx_fifo, newest);
+ end = ooo_segment_end_offset (s0->server_rx_fifo, newest);
tcp_update_sack_list (tc, start, end);
}
}
/**
- * Check if ACK could be delayed. DELACK timer is set only after frame is
- * processed so this can return true for a full bursts of packets.
+ * Check if ACK could be delayed. If ack can be delayed, it should return
+ * true for a full frame. If we're always acking return 0.
*/
always_inline int
tcp_can_delack (tcp_connection_t * tc)
{
- /* If there's no DELACK timer set and the last window sent wasn't 0 we
- * can safely delay. */
- if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK)
- && (tc->flags & TCP_CONN_SENT_RCV_WND0) == 0
- && (tc->flags & TCP_CONN_SNDACK) == 0)
- return 1;
+ /* Send ack if ... */
+ if (TCP_ALWAYS_ACK
+ /* just sent a rcv wnd 0 */
+ || (tc->flags & TCP_CONN_SENT_RCV_WND0) != 0
+ /* constrained to send ack */
+ || (tc->flags & TCP_CONN_SNDACK) != 0
+ /* we're almost out of tx wnd */
+ || tcp_available_snd_space (tc) < 2 * tc->snd_mss)
+ return 0;
- return 0;
+ return 1;
}
static int
tcp_segment_rcv (tcp_main_t * tm, tcp_connection_t * tc, vlib_buffer_t * b,
u16 n_data_bytes, u32 * next0)
{
- u32 error = 0;
+ u32 error = 0, n_bytes_to_drop;
/* Handle out-of-order data */
if (PREDICT_FALSE (vnet_buffer (b)->tcp.seq_number != tc->rcv_nxt))
{
- error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
-
- /* Don't send more than 3 dupacks per burst
- * XXX decide if this is good */
- if (tc->snt_dupacks < 3)
+ /* Old sequence numbers allowed through because they overlapped
+ * the rx window */
+ if (seq_lt (vnet_buffer (b)->tcp.seq_number, tc->rcv_nxt))
{
- /* RFC2581: Send DUPACK for fast retransmit */
- tcp_make_ack (tc, b);
- *next0 = tcp_next_output (tc->c_is_ip4);
+ error = TCP_ERROR_SEGMENT_OLD;
+ *next0 = TCP_NEXT_DROP;
- /* Mark as DUPACK. We may filter these in output if
- * the burst fills the holes. */
- vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_DUPACK;
+ /* Completely in the past (possible retransmit) */
+ if (seq_lt (vnet_buffer (b)->tcp.seq_end, tc->rcv_nxt))
+ goto done;
- tc->snt_dupacks++;
+ /* Chop off the bytes in the past */
+ n_bytes_to_drop = tc->rcv_nxt - vnet_buffer (b)->tcp.seq_number;
+ n_data_bytes -= n_bytes_to_drop;
+ vlib_buffer_advance (b, n_bytes_to_drop);
+
+ goto in_order;
}
+ error = tcp_session_enqueue_ooo (tc, b, n_data_bytes);
+
+ /* N.B. Should not filter burst of dupacks. Two issues 1) dupacks open
+ * cwnd on remote peer when congested 2) acks leaving should have the
+ * latest rcv_wnd since the burst may eaten up all of it, so only the
+ * old ones could be filtered.
+ */
+
+ /* RFC2581: Send DUPACK for fast retransmit */
+ tcp_make_ack (tc, b);
+ *next0 = tcp_next_output (tc->c_is_ip4);
+
+ /* Mark as DUPACK. We may filter these in output if
+ * the burst fills the holes. */
+ if (n_data_bytes)
+ vnet_buffer (b)->tcp.flags = TCP_BUF_FLAG_DUPACK;
+
+ TCP_EVT_DBG (TCP_EVT_DUPACK_SENT, tc);
goto done;
}
+in_order:
+
/* In order data, enqueue. Fifo figures out by itself if any out-of-order
* segments can be enqueued after fifo tail offset changes. */
error = tcp_session_enqueue_data (tc, b, n_data_bytes);
+ if (n_data_bytes == 0)
+ {
+ *next0 = TCP_NEXT_DROP;
+ goto done;
+ }
+
/* Check if ACK can be delayed */
if (tcp_can_delack (tc))
{
- /* Nothing to do for pure ACKs */
- if (n_data_bytes == 0)
- goto done;
-
- /* If connection has not been previously marked for delay ack
- * add it to the list and flag it */
- if (!tc->flags & TCP_CONN_DELACK)
- {
- vec_add1 (tm->delack_connections[tc->c_thread_index],
- tc->c_c_index);
- tc->flags |= TCP_CONN_DELACK;
- }
+ if (!tcp_timer_is_active (tc, TCP_TIMER_DELACK))
+ tcp_timer_set (tc, TCP_TIMER_DELACK, TCP_DELACK_TIME);
+ goto done;
}
- else
- {
- /* Check if a packet has already been enqueued to output for burst.
- * If yes, then drop this one, otherwise, let it pass through to
- * output */
- if ((tc->flags & TCP_CONN_BURSTACK) == 0)
- {
- *next0 = tcp_next_output (tc->c_is_ip4);
- tcp_make_ack (tc, b);
- error = TCP_ERROR_ENQUEUED;
- /* TODO: maybe add counter to ensure N acks will be sent/burst */
- tc->flags |= TCP_CONN_BURSTACK;
- }
- }
+ *next0 = tcp_next_output (tc->c_is_ip4);
+ tcp_make_ack (tc, b);
done:
return error;
}
-void
-delack_timers_init (tcp_main_t * tm, u32 thread_index)
+typedef struct
{
- tcp_connection_t *tc;
- u32 i, *conns;
- tw_timer_wheel_16t_2w_512sl_t *tw;
+ tcp_header_t tcp_header;
+ tcp_connection_t tcp_connection;
+} tcp_rx_trace_t;
- tw = &tm->timer_wheels[thread_index];
- conns = tm->delack_connections[thread_index];
- for (i = 0; i < vec_len (conns); i++)
- {
- tc = pool_elt_at_index (tm->connections[thread_index], conns[i]);
- ASSERT (0 != tc);
+u8 *
+format_tcp_rx_trace (u8 * s, va_list * args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
+ uword indent = format_get_indent (s);
+
+ s = format (s, "%U\n%U%U",
+ format_tcp_header, &t->tcp_header, 128,
+ format_white_space, indent,
+ format_tcp_connection, &t->tcp_connection, 1);
- tc->timers[TCP_TIMER_DELACK]
- = tw_timer_start_16t_2w_512sl (tw, conns[i],
- TCP_TIMER_DELACK, TCP_DELACK_TIME);
+ return s;
+}
+
+u8 *
+format_tcp_rx_trace_short (u8 * s, va_list * args)
+{
+ CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
+ CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
+ tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
+
+ s = format (s, "%d -> %d (%U)",
+ clib_net_to_host_u16 (t->tcp_header.src_port),
+ clib_net_to_host_u16 (t->tcp_header.dst_port), format_tcp_state,
+ t->tcp_connection.state);
+
+ return s;
+}
+
+void
+tcp_set_rx_trace_data (tcp_rx_trace_t * t0, tcp_connection_t * tc0,
+ tcp_header_t * th0, vlib_buffer_t * b0, u8 is_ip4)
+{
+ if (tc0)
+ {
+ clib_memcpy (&t0->tcp_connection, tc0, sizeof (t0->tcp_connection));
+ }
+ else
+ {
+ th0 = tcp_buffer_hdr (b0);
}
- vec_reset_length (tm->delack_connections[thread_index]);
+ clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header));
+}
+
+always_inline void
+tcp_established_inc_counter (vlib_main_t * vm, u8 is_ip4, u8 evt, u8 val)
+{
+ if (PREDICT_TRUE (!val))
+ return;
+
+ if (is_ip4)
+ vlib_node_increment_counter (vm, tcp4_established_node.index, evt, val);
+ else
+ vlib_node_increment_counter (vm, tcp6_established_node.index, evt, val);
}
always_inline uword
vlib_frame_t * from_frame, int is_ip4)
{
u32 n_left_from, next_index, *from, *to_next;
- u32 my_thread_index = vm->cpu_index, errors = 0;
+ u32 my_thread_index = vm->thread_index, errors = 0;
tcp_main_t *tm = vnet_get_tcp_main ();
+ u8 is_fin = 0;
from = vlib_frame_vector_args (from_frame);
n_left_from = from_frame->n_vectors;
vlib_buffer_t *b0;
tcp_header_t *th0 = 0;
tcp_connection_t *tc0;
- ip4_header_t *ip40;
- ip6_header_t *ip60;
- u32 n_advance_bytes0, n_data_bytes0;
u32 next0 = TCP_ESTABLISHED_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
bi0 = from[0];
tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
my_thread_index);
- /* Checksum computed by ipx_local no need to compute again */
-
- if (is_ip4)
- {
- ip40 = vlib_buffer_get_current (b0);
- th0 = ip4_next_header (ip40);
- n_advance_bytes0 = (ip4_header_bytes (ip40)
- + tcp_header_bytes (th0));
- n_data_bytes0 = clib_net_to_host_u16 (ip40->length)
- - n_advance_bytes0;
- }
- else
+ if (PREDICT_FALSE (tc0 == 0))
{
- ip60 = vlib_buffer_get_current (b0);
- th0 = ip6_next_header (ip60);
- n_advance_bytes0 = tcp_header_bytes (th0);
- n_data_bytes0 = clib_net_to_host_u16 (ip60->payload_length)
- - n_advance_bytes0;
- n_advance_bytes0 += sizeof (ip60[0]);
+ error0 = TCP_ERROR_INVALID_CONNECTION;
+ goto done;
}
+ th0 = tcp_buffer_hdr (b0);
+
+ is_fin = (th0->flags & TCP_FLAG_FIN) != 0;
+
/* SYNs, FINs and data consume sequence numbers */
vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
- + tcp_is_syn (th0) + tcp_is_fin (th0) + n_data_bytes0;
+ + tcp_is_syn (th0) + is_fin + vnet_buffer (b0)->tcp.data_len;
/* TODO header prediction fast path */
if (PREDICT_FALSE (tcp_segment_validate (vm, tc0, b0, th0, &next0)))
{
error0 = TCP_ERROR_SEGMENT_INVALID;
- goto drop;
+ TCP_EVT_DBG (TCP_EVT_SEG_INVALID, tc0,
+ vnet_buffer (b0)->tcp.seq_number,
+ vnet_buffer (b0)->tcp.seq_end);
+ goto done;
}
/* 5: check the ACK field */
if (tcp_rcv_ack (tc0, b0, th0, &next0, &error0))
{
- goto drop;
+ goto done;
}
/* 6: check the URG bit TODO */
/* 7: process the segment text */
- vlib_buffer_advance (b0, n_advance_bytes0);
- error0 = tcp_segment_rcv (tm, tc0, b0, n_data_bytes0, &next0);
+
+ vlib_buffer_advance (b0, vnet_buffer (b0)->tcp.data_offset);
+ error0 = tcp_segment_rcv (tm, tc0, b0,
+ vnet_buffer (b0)->tcp.data_len, &next0);
+
+ /* N.B. buffer is rewritten if segment is ooo. Thus, th0 becomes a
+ * dangling reference. */
/* 8: check the FIN bit */
- if (tcp_fin (th0))
+ if (is_fin)
{
- /* Send ACK and enter CLOSE-WAIT */
- tcp_make_ack (tc0, b0);
- tcp_connection_force_ack (tc0, b0);
- next0 = tcp_next_output (tc0->c_is_ip4);
+ /* Enter CLOSE-WAIT and notify session. Don't send ACK, instead
+ * wait for session to call close. To avoid lingering
+ * in CLOSE-WAIT, set timer (reuse WAITCLOSE). */
tc0->state = TCP_STATE_CLOSE_WAIT;
+ TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc0);
stream_session_disconnect_notify (&tc0->connection);
+ tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
}
- drop:
+ done:
b0->error = node->errors[error0];
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
{
-
+ tcp_rx_trace_t *t0 =
+ vlib_add_trace (vm, node, b0, sizeof (*t0));
+ tcp_set_rx_trace_data (t0, tc0, th0, b0, is_ip4);
}
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
}
errors = session_manager_flush_enqueue_events (my_thread_index);
- if (errors)
- {
- if (is_ip4)
- vlib_node_increment_counter (vm, tcp4_established_node.index,
- TCP_ERROR_EVENT_FIFO_FULL, errors);
- else
- vlib_node_increment_counter (vm, tcp6_established_node.index,
- TCP_ERROR_EVENT_FIFO_FULL, errors);
- }
-
- delack_timers_init (tm, my_thread_index);
+ tcp_established_inc_counter (vm, is_ip4, TCP_ERROR_EVENT_FIFO_FULL, errors);
return from_frame->n_vectors;
}
.name = "tcp4-established",
/* Takes a vector of packets. */
.vector_size = sizeof (u32),
- .n_errors = TCP_N_ERROR,.error_strings = tcp_error_strings,
+ .n_errors = TCP_N_ERROR,
+ .error_strings = tcp_error_strings,
.n_next_nodes = TCP_ESTABLISHED_N_NEXT,
.next_nodes =
{
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
{
tcp_main_t *tm = vnet_get_tcp_main ();
u32 n_left_from, next_index, *from, *to_next;
- u32 my_thread_index = vm->cpu_index, errors = 0;
+ u32 my_thread_index = vm->thread_index, errors = 0;
u8 sst = is_ip4 ? SESSION_TYPE_IP4_TCP : SESSION_TYPE_IP6_TCP;
from = vlib_frame_vector_args (from_frame);
{
u32 bi0, ack0, seq0;
vlib_buffer_t *b0;
+ tcp_rx_trace_t *t0;
tcp_header_t *tcp0 = 0;
tcp_connection_t *tc0;
- ip4_header_t *ip40;
- ip6_header_t *ip60;
- u32 n_advance_bytes0, n_data_bytes0;
tcp_connection_t *new_tc0;
u32 next0 = TCP_SYN_SENT_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
ack0 = vnet_buffer (b0)->tcp.ack_number;
seq0 = vnet_buffer (b0)->tcp.seq_number;
-
- /* Checksum computed by ipx_local no need to compute again */
-
- if (is_ip4)
- {
- ip40 = vlib_buffer_get_current (b0);
- tcp0 = ip4_next_header (ip40);
- n_advance_bytes0 = (ip4_header_bytes (ip40)
- + tcp_header_bytes (tcp0));
- n_data_bytes0 = clib_net_to_host_u16 (ip40->length)
- - n_advance_bytes0;
- }
- else
- {
- ip60 = vlib_buffer_get_current (b0);
- tcp0 = ip6_next_header (ip60);
- n_advance_bytes0 = tcp_header_bytes (tcp0);
- n_data_bytes0 = clib_net_to_host_u16 (ip60->payload_length)
- - n_advance_bytes0;
- n_advance_bytes0 += sizeof (ip60[0]);
- }
+ tcp0 = tcp_buffer_hdr (b0);
if (PREDICT_FALSE
(!tcp_ack (tcp0) && !tcp_rst (tcp0) && !tcp_syn (tcp0)))
/* SYNs, FINs and data consume sequence numbers */
vnet_buffer (b0)->tcp.seq_end = seq0 + tcp_is_syn (tcp0)
- + tcp_is_fin (tcp0) + n_data_bytes0;
+ + tcp_is_fin (tcp0) + vnet_buffer (b0)->tcp.data_len;
/*
* 1. check the ACK bit
clib_memcpy (new_tc0, tc0, sizeof (*new_tc0));
new_tc0->c_thread_index = my_thread_index;
+ new_tc0->c_c_index = new_tc0 - tm->connections[my_thread_index];
/* Cleanup half-open connection XXX lock */
pool_put (tm->half_open_connections, tc0);
new_tc0->irs = seq0;
/* Parse options */
- tcp_options_parse (tcp0, &new_tc0->opt);
+ if (tcp_options_parse (tcp0, &new_tc0->opt))
+ goto drop;
if (tcp_opts_tstamp (&new_tc0->opt))
{
/* Notify app that we have connection */
stream_session_connect_notify (&new_tc0->connection, sst, 0);
+ stream_session_init_fifos_pointers (&new_tc0->connection,
+ new_tc0->irs + 1,
+ new_tc0->iss + 1);
/* Make sure after data segment processing ACK is sent */
new_tc0->flags |= TCP_CONN_SNDACK;
}
{
new_tc0->state = TCP_STATE_SYN_RCVD;
- /* Notify app that we have connection XXX */
+ /* Notify app that we have connection */
stream_session_connect_notify (&new_tc0->connection, sst, 0);
-
+ stream_session_init_fifos_pointers (&new_tc0->connection,
+ new_tc0->irs + 1,
+ new_tc0->iss + 1);
tcp_make_synack (new_tc0, b0);
next0 = tcp_next_output (is_ip4);
}
/* Read data, if any */
- if (n_data_bytes0)
+ if (vnet_buffer (b0)->tcp.data_len)
{
- error0 =
- tcp_segment_rcv (tm, new_tc0, b0, n_data_bytes0, &next0);
+ vlib_buffer_advance (b0, vnet_buffer (b0)->tcp.data_offset);
+ error0 = tcp_segment_rcv (tm, new_tc0, b0,
+ vnet_buffer (b0)->tcp.data_len,
+ &next0);
if (error0 == TCP_ERROR_PURE_ACK)
error0 = TCP_ERROR_SYN_ACKS_RCVD;
}
b0->error = error0 ? node->errors[error0] : 0;
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
{
-
+ t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
+ clib_memcpy (&t0->tcp_header, tcp0, sizeof (t0->tcp_header));
+ clib_memcpy (&t0->tcp_connection, tc0,
+ sizeof (t0->tcp_connection));
}
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
#define _(s,n) [TCP_SYN_SENT_NEXT_##s] = n,
foreach_tcp_state_next
#undef _
- }
-,};
+ },
+ .format_trace = format_tcp_rx_trace_short,
+};
/* *INDENT-ON* */
VLIB_NODE_FUNCTION_MULTIARCH (tcp6_syn_sent_node, tcp6_syn_sent_rcv);
/**
- * Handles reception for all states except LISTEN, SYN-SEND and ESTABLISHED
+ * Handles reception for all states except LISTEN, SYN-SENT and ESTABLISHED
* as per RFC793 p. 64
*/
always_inline uword
{
tcp_main_t *tm = vnet_get_tcp_main ();
u32 n_left_from, next_index, *from, *to_next;
- u32 my_thread_index = vm->cpu_index, errors = 0;
+ u32 my_thread_index = vm->thread_index, errors = 0;
from = vlib_frame_vector_args (from_frame);
n_left_from = from_frame->n_vectors;
vlib_buffer_t *b0;
tcp_header_t *tcp0 = 0;
tcp_connection_t *tc0;
- ip4_header_t *ip40;
- ip6_header_t *ip60;
- u32 n_advance_bytes0, n_data_bytes0;
u32 next0 = TCP_RCV_PROCESS_NEXT_DROP, error0 = TCP_ERROR_ENQUEUED;
bi0 = from[0];
b0 = vlib_get_buffer (vm, bi0);
tc0 = tcp_connection_get (vnet_buffer (b0)->tcp.connection_index,
my_thread_index);
-
- /* Checksum computed by ipx_local no need to compute again */
-
- if (is_ip4)
+ if (PREDICT_FALSE (tc0 == 0))
{
- ip40 = vlib_buffer_get_current (b0);
- tcp0 = ip4_next_header (ip40);
- n_advance_bytes0 = (ip4_header_bytes (ip40)
- + tcp_header_bytes (tcp0));
- n_data_bytes0 = clib_net_to_host_u16 (ip40->length)
- - n_advance_bytes0;
- }
- else
- {
- ip60 = vlib_buffer_get_current (b0);
- tcp0 = ip6_next_header (ip60);
- n_advance_bytes0 = tcp_header_bytes (tcp0);
- n_data_bytes0 = clib_net_to_host_u16 (ip60->payload_length)
- - n_advance_bytes0;
- n_advance_bytes0 += sizeof (ip60[0]);
+ error0 = TCP_ERROR_INVALID_CONNECTION;
+ goto drop;
}
+ tcp0 = tcp_buffer_hdr (b0);
+
/* SYNs, FINs and data consume sequence numbers */
vnet_buffer (b0)->tcp.seq_end = vnet_buffer (b0)->tcp.seq_number
- + tcp_is_syn (tcp0) + tcp_is_fin (tcp0) + n_data_bytes0;
+ + tcp_is_syn (tcp0) + tcp_is_fin (tcp0)
+ + vnet_buffer (b0)->tcp.data_len;
/*
* Special treatment for CLOSED
tcp_send_reset (b0, is_ip4);
goto drop;
}
+
+ /* Update rtt and rto */
+ tc0->bytes_acked = 1;
+ tcp_update_rtt (tc0, vnet_buffer (b0)->tcp.ack_number);
+
/* Switch state to ESTABLISHED */
tc0->state = TCP_STATE_ESTABLISHED;
/* Shoulder tap the server */
stream_session_accept_notify (&tc0->connection);
- tcp_timer_reset (tc0, TCP_TIMER_RETRANSMIT_SYN);
+ /* Reset SYN-ACK retransmit timer */
+ tcp_retransmit_timer_reset (tc0);
break;
case TCP_STATE_ESTABLISHED:
/* We can get packets in established state here because they
* continue processing in that state. */
if (tcp_rcv_ack (tc0, b0, tcp0, &next0, &error0))
goto drop;
- tc0->state = TCP_STATE_FIN_WAIT_2;
- /* Stop all timers, 2MSL will be set lower */
- tcp_connection_timers_reset (tc0);
+
+ /* If FIN is ACKed */
+ if (tc0->snd_una == tc0->snd_una_max)
+ {
+ tc0->state = TCP_STATE_FIN_WAIT_2;
+ /* Stop all timers, 2MSL will be set lower */
+ tcp_connection_timers_reset (tc0);
+ }
break;
case TCP_STATE_FIN_WAIT_2:
/* In addition to the processing for the ESTABLISHED state, if
if (!tcp_rcv_ack_is_acceptable (tc0, b0))
goto drop;
- tcp_connection_del (tc0);
+ tc0->state = TCP_STATE_CLOSED;
+
+ /* Don't delete the connection/session yet. Instead, wait a
+ * reasonable amount of time until the pipes are cleared. In
+ * particular, this makes sure that we won't have dead sessions
+ * when processing events on the tx path */
+ tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_CLEANUP_TIME);
+
+ /* Stop retransmit */
+ tcp_retransmit_timer_reset (tc0);
+
goto drop;
break;
case TCP_STATE_ESTABLISHED:
case TCP_STATE_FIN_WAIT_1:
case TCP_STATE_FIN_WAIT_2:
- error0 = tcp_segment_rcv (tm, tc0, b0, n_data_bytes0, &next0);
+ vlib_buffer_advance (b0, vnet_buffer (b0)->tcp.data_offset);
+ error0 = tcp_segment_rcv (tm, tc0, b0,
+ vnet_buffer (b0)->tcp.data_len,
+ &next0);
break;
case TCP_STATE_CLOSE_WAIT:
case TCP_STATE_CLOSING:
case TCP_STATE_SYN_RCVD:
/* Send FIN-ACK notify app and enter CLOSE-WAIT */
tcp_connection_timers_reset (tc0);
- tcp_make_finack (tc0, b0);
+ tcp_make_fin (tc0, b0);
next0 = tcp_next_output (tc0->c_is_ip4);
stream_session_disconnect_notify (&tc0->connection);
tc0->state = TCP_STATE_CLOSE_WAIT;
case TCP_STATE_FIN_WAIT_1:
tc0->state = TCP_STATE_TIME_WAIT;
tcp_connection_timers_reset (tc0);
- tcp_timer_set (tc0, TCP_TIMER_2MSL, TCP_2MSL_TIME);
+ tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
break;
case TCP_STATE_FIN_WAIT_2:
/* Got FIN, send ACK! */
tc0->state = TCP_STATE_TIME_WAIT;
- tcp_timer_set (tc0, TCP_TIMER_2MSL, TCP_2MSL_TIME);
+ tcp_connection_timers_reset (tc0);
+ tcp_timer_set (tc0, TCP_TIMER_WAITCLOSE, TCP_CLOSEWAIT_TIME);
tcp_make_ack (tc0, b0);
next0 = tcp_next_output (is_ip4);
break;
/* Remain in the TIME-WAIT state. Restart the 2 MSL time-wait
* timeout.
*/
- tcp_timer_update (tc0, TCP_TIMER_2MSL, TCP_2MSL_TIME);
+ tcp_timer_update (tc0, TCP_TIMER_WAITCLOSE, TCP_2MSL_TIME);
break;
}
+ TCP_EVT_DBG (TCP_EVT_FIN_RCVD, tc0);
+ drop:
b0->error = error0 ? node->errors[error0] : 0;
- drop:
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
{
-
+ tcp_rx_trace_t *t0 =
+ vlib_add_trace (vm, node, b0, sizeof (*t0));
+ tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
}
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
vlib_frame_t * from_frame, int is_ip4)
{
u32 n_left_from, next_index, *from, *to_next;
- u32 my_thread_index = vm->cpu_index;
+ u32 my_thread_index = vm->thread_index;
tcp_main_t *tm = vnet_get_tcp_main ();
u8 sst = is_ip4 ? SESSION_TYPE_IP4_TCP : SESSION_TYPE_IP6_TCP;
{
u32 bi0;
vlib_buffer_t *b0;
+ tcp_rx_trace_t *t0;
tcp_header_t *th0 = 0;
tcp_connection_t *lc0;
ip4_header_t *ip40;
/* Create child session. For syn-flood protection use filter */
- /* 1. first check for an RST */
- if (tcp_rst (th0))
- goto drop;
+ /* 1. first check for an RST: handled in dispatch */
+ /* if (tcp_rst (th0))
+ goto drop; */
- /* 2. second check for an ACK */
- if (tcp_ack (th0))
- {
- tcp_send_reset (b0, is_ip4);
- goto drop;
- }
+ /* 2. second check for an ACK: handled in dispatch */
+ /* if (tcp_ack (th0))
+ {
+ tcp_send_reset (b0, is_ip4);
+ goto drop;
+ } */
/* 3. check for a SYN (did that already) */
child0->c_rmt_port = th0->src_port;
child0->c_is_ip4 = is_ip4;
child0->c_thread_index = my_thread_index;
+ child0->state = TCP_STATE_SYN_RCVD;
if (is_ip4)
{
goto drop;
}
- tcp_options_parse (th0, &child0->opt);
+ if (tcp_options_parse (th0, &child0->opt))
+ {
+ goto drop;
+ }
child0->irs = vnet_buffer (b0)->tcp.seq_number;
child0->rcv_nxt = vnet_buffer (b0)->tcp.seq_number + 1;
- child0->state = TCP_STATE_SYN_RCVD;
+ child0->rcv_las = child0->rcv_nxt;
/* RFC1323: TSval timestamps sent on {SYN} and {SYN,ACK}
* segments are used to initialize PAWS. */
tcp_connection_init_vars (child0);
+ TCP_EVT_DBG (TCP_EVT_SYN_RCVD, child0);
+
/* Reuse buffer to make syn-ack and send */
tcp_make_synack (child0, b0);
next0 = tcp_next_output (is_ip4);
+ /* Init fifo pointers after we have iss */
+ stream_session_init_fifos_pointers (&child0->connection,
+ child0->irs + 1,
+ child0->iss + 1);
drop:
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
{
-
+ t0 = vlib_add_trace (vm, node, b0, sizeof (*t0));
+ clib_memcpy (&t0->tcp_header, th0, sizeof (t0->tcp_header));
+ clib_memcpy (&t0->tcp_connection, lc0,
+ sizeof (t0->tcp_connection));
}
b0->error = node->errors[error0];
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
foreach_tcp_state_next
#undef _
},
+ .format_trace = format_tcp_rx_trace_short,
};
/* *INDENT-ON* */
_ (ESTABLISHED, "tcp6-established") \
_ (RESET, "tcp6-reset")
-typedef struct
-{
- u16 src_port;
- u16 dst_port;
- u8 state;
-} tcp_rx_trace_t;
-
-const char *tcp_fsm_states[] = {
-#define _(sym, str) str,
- foreach_tcp_fsm_state
-#undef _
-};
-
-u8 *
-format_tcp_state (u8 * s, va_list * args)
-{
- tcp_state_t *state = va_arg (*args, tcp_state_t *);
-
- if (state[0] < TCP_N_STATES)
- s = format (s, "%s", tcp_fsm_states[state[0]]);
- else
- s = format (s, "UNKNOWN");
-
- return s;
-}
-
-u8 *
-format_tcp_rx_trace (u8 * s, va_list * args)
-{
- CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *);
- CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *);
- tcp_rx_trace_t *t = va_arg (*args, tcp_rx_trace_t *);
-
- s = format (s, "TCP: src-port %d dst-port %U%s\n",
- clib_net_to_host_u16 (t->src_port),
- clib_net_to_host_u16 (t->dst_port), format_tcp_state, t->state);
-
- return s;
-}
-
#define filter_flags (TCP_FLAG_SYN|TCP_FLAG_ACK|TCP_FLAG_RST|TCP_FLAG_FIN)
always_inline uword
vlib_frame_t * from_frame, int is_ip4)
{
u32 n_left_from, next_index, *from, *to_next;
- u32 my_thread_index = vm->cpu_index;
+ u32 my_thread_index = vm->thread_index;
tcp_main_t *tm = vnet_get_tcp_main ();
from = vlib_frame_vector_args (from_frame);
while (n_left_from > 0 && n_left_to_next > 0)
{
+ int n_advance_bytes0, n_data_bytes0;
u32 bi0;
vlib_buffer_t *b0;
tcp_header_t *tcp0 = 0;
n_left_to_next -= 1;
b0 = vlib_get_buffer (vm, bi0);
+ vnet_buffer (b0)->tcp.flags = 0;
+
+ /* Checksum computed by ipx_local no need to compute again */
if (is_ip4)
{
ip40 = vlib_buffer_get_current (b0);
tcp0 = ip4_next_header (ip40);
+ n_advance_bytes0 = (ip4_header_bytes (ip40)
+ + tcp_header_bytes (tcp0));
+ n_data_bytes0 = clib_net_to_host_u16 (ip40->length)
+ - n_advance_bytes0;
/* lookup session */
tc0 =
{
ip60 = vlib_buffer_get_current (b0);
tcp0 = ip6_next_header (ip60);
+ n_advance_bytes0 = tcp_header_bytes (tcp0);
+ n_data_bytes0 = clib_net_to_host_u16 (ip60->payload_length)
+ - n_advance_bytes0;
+ n_advance_bytes0 += sizeof (ip60[0]);
+
tc0 =
(tcp_connection_t *)
stream_session_lookup_transport6 (&ip60->src_address,
my_thread_index);
}
+ /* Length check */
+ if (PREDICT_FALSE (n_advance_bytes0 < 0))
+ {
+ error0 = TCP_ERROR_LENGTH;
+ goto done;
+ }
+
/* Session exists */
if (PREDICT_TRUE (0 != tc0))
{
vnet_buffer (b0)->tcp.ack_number =
clib_net_to_host_u32 (tcp0->ack_number);
+ vnet_buffer (b0)->tcp.hdr_offset = (u8 *) tcp0
+ - (u8 *) vlib_buffer_get_current (b0);
+ vnet_buffer (b0)->tcp.data_offset = n_advance_bytes0;
+ vnet_buffer (b0)->tcp.data_len = n_data_bytes0;
+
flags0 = tcp0->flags & filter_flags;
next0 = tm->dispatch_table[tc0->state][flags0].next;
error0 = tm->dispatch_table[tc0->state][flags0].error;
- if (PREDICT_FALSE (error0 == TCP_ERROR_DISPATCH))
+ if (PREDICT_FALSE (error0 == TCP_ERROR_DISPATCH
+ || next0 == TCP_INPUT_NEXT_RESET))
{
/* Overload tcp flags to store state */
+ tcp_state_t state0 = tc0->state;
vnet_buffer (b0)->tcp.flags = tc0->state;
+
+ if (error0 == TCP_ERROR_DISPATCH)
+ clib_warning ("disp error state %U flags %U",
+ format_tcp_state, state0, format_tcp_flags,
+ (int) flags0);
}
}
else
/* Send reset */
next0 = TCP_INPUT_NEXT_RESET;
error0 = TCP_ERROR_NO_LISTENER;
- vnet_buffer (b0)->tcp.flags = 0;
}
+ done:
b0->error = error0 ? node->errors[error0] : 0;
if (PREDICT_FALSE (b0->flags & VLIB_BUFFER_IS_TRACED))
{
-
+ tcp_rx_trace_t *t0 =
+ vlib_add_trace (vm, node, b0, sizeof (*t0));
+ tcp_set_rx_trace_data (t0, tc0, tcp0, b0, is_ip4);
}
vlib_validate_buffer_enqueue_x1 (vm, node, next_index, to_next,
/* *INDENT-ON* */
VLIB_NODE_FUNCTION_MULTIARCH (tcp6_input_node, tcp6_input);
-void
-tcp_update_time (f64 now, u32 thread_index)
-{
- tcp_main_t *tm = vnet_get_tcp_main ();
- tw_timer_expire_timers_16t_2w_512sl (&tm->timer_wheels[thread_index], now);
-}
static void
tcp_dispatch_table_init (tcp_main_t * tm)
/* SYNs for new connections -> tcp-listen. */
_(LISTEN, TCP_FLAG_SYN, TCP_INPUT_NEXT_LISTEN, TCP_ERROR_NONE);
+ _(LISTEN, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_NONE);
+ _(LISTEN, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_NONE);
/* ACK for for a SYN-ACK -> tcp-rcv-process. */
_(SYN_RCVD, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(SYN_RCVD, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
/* SYN-ACK for a SYN */
_(SYN_SENT, TCP_FLAG_SYN | TCP_FLAG_ACK, TCP_INPUT_NEXT_SYN_SENT,
TCP_ERROR_NONE);
_(ESTABLISHED, TCP_FLAG_FIN, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
_(ESTABLISHED, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
TCP_ERROR_NONE);
+ _(ESTABLISHED, TCP_FLAG_RST, TCP_INPUT_NEXT_ESTABLISHED, TCP_ERROR_NONE);
+ _(ESTABLISHED, TCP_FLAG_RST | TCP_FLAG_ACK, TCP_INPUT_NEXT_ESTABLISHED,
+ TCP_ERROR_NONE);
/* ACK or FIN-ACK to our FIN */
_(FIN_WAIT_1, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
_(FIN_WAIT_1, TCP_FLAG_ACK | TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS,
_(FIN_WAIT_1, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
/* FIN confirming that the peer (app) has closed */
_(FIN_WAIT_2, TCP_FLAG_FIN, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(FIN_WAIT_2, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
_(FIN_WAIT_2, TCP_FLAG_FIN | TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS,
TCP_ERROR_NONE);
_(LAST_ACK, TCP_FLAG_ACK, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(LAST_ACK, TCP_FLAG_RST, TCP_INPUT_NEXT_RCV_PROCESS, TCP_ERROR_NONE);
+ _(CLOSED, TCP_FLAG_ACK, TCP_INPUT_NEXT_RESET, TCP_ERROR_CONNECTION_CLOSED);
+ _(CLOSED, TCP_FLAG_RST, TCP_INPUT_NEXT_DROP, TCP_ERROR_CONNECTION_CLOSED);
#undef _
}
Code Review / vpp.git / blobdiff