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#include <import/eb64tree.h>
#include <haproxy/quic_conn-t.h>
#include <haproxy/quic_loss.h>
#include <haproxy/quic_tls.h>
#include <haproxy/atomic.h>
#include <haproxy/list.h>
#include <haproxy/ticks.h>
#include <haproxy/trace.h>
#define TRACE_SOURCE &trace_quic
/* Update <ql> QUIC loss information with new <rtt> measurement and <ack_delay>
* on ACK frame receipt which MUST be min(ack->ack_delay, max_ack_delay)
* before the handshake is confirmed.
*/
void quic_loss_srtt_update(struct quic_loss *ql,
unsigned int rtt, unsigned int ack_delay,
struct quic_conn *qc)
{
TRACE_ENTER(QUIC_EV_CONN_RTTUPDT, qc);
TRACE_DEVEL("Loss info update", QUIC_EV_CONN_RTTUPDT, qc, &rtt, &ack_delay, ql);
ql->latest_rtt = rtt;
if (!ql->rtt_min) {
/* No previous measurement. */
ql->srtt = rtt << 3;
/* rttval <- rtt / 2 or 4*rttval <- 2*rtt. */
ql->rtt_var = rtt << 1;
ql->rtt_min = rtt;
}
else {
int diff;
ql->rtt_min = QUIC_MIN(rtt, ql->rtt_min);
/* Specific to QUIC (RTT adjustment). */
if (ack_delay && rtt > ql->rtt_min + ack_delay)
rtt -= ack_delay;
diff = ql->srtt - rtt;
if (diff < 0)
diff = -diff;
/* 4*rttvar = 3*rttvar + |diff| */
ql->rtt_var += diff - (ql->rtt_var >> 2);
/* 8*srtt = 7*srtt + rtt */
ql->srtt += rtt - (ql->srtt >> 3);
}
TRACE_DEVEL("Loss info update", QUIC_EV_CONN_RTTUPDT, qc,,, ql);
TRACE_LEAVE(QUIC_EV_CONN_RTTUPDT, qc);
}
/* Returns for <qc> QUIC connection the first packet number space which
* experienced packet loss, if any or a packet number space with
* TICK_ETERNITY as packet loss time if not.
*/
struct quic_pktns *quic_loss_pktns(struct quic_conn *qc)
{
enum quic_tls_pktns i;
struct quic_pktns *pktns;
TRACE_ENTER(QUIC_EV_CONN_SPTO, qc);
pktns = &qc->pktns[QUIC_TLS_PKTNS_INITIAL];
TRACE_DEVEL("pktns", QUIC_EV_CONN_SPTO, qc, pktns);
for (i = QUIC_TLS_PKTNS_HANDSHAKE; i < QUIC_TLS_PKTNS_MAX; i++) {
TRACE_DEVEL("pktns", QUIC_EV_CONN_SPTO, qc, &qc->pktns[i]);
if (!tick_isset(pktns->tx.loss_time) ||
qc->pktns[i].tx.loss_time < pktns->tx.loss_time)
pktns = &qc->pktns[i];
}
TRACE_LEAVE(QUIC_EV_CONN_SPTO, qc);
return pktns;
}
/* Returns for <qc> QUIC connection the first packet number space to
* arm the PTO for if any or a packet number space with TICK_ETERNITY
* as PTO value if not.
*/
struct quic_pktns *quic_pto_pktns(struct quic_conn *qc,
int handshake_confirmed,
unsigned int *pto)
{
int i;
unsigned int duration, lpto;
struct quic_loss *ql = &qc->path->loss;
struct quic_pktns *pktns, *p;
TRACE_ENTER(QUIC_EV_CONN_SPTO, qc);
duration =
(ql->srtt >> 3) +
(QUIC_MAX(ql->rtt_var, QUIC_TIMER_GRANULARITY) << ql->pto_count);
if (!qc->path->in_flight) {
struct quic_enc_level *hel;
hel = &qc->els[QUIC_TLS_ENC_LEVEL_HANDSHAKE];
if (quic_tls_has_tx_sec(hel)) {
pktns = &qc->pktns[QUIC_TLS_PKTNS_HANDSHAKE];
}
else {
pktns = &qc->pktns[QUIC_TLS_PKTNS_INITIAL];
}
lpto = tick_add(now_ms, duration);
goto out;
}
lpto = TICK_ETERNITY;
pktns = p = &qc->pktns[QUIC_TLS_PKTNS_INITIAL];
for (i = QUIC_TLS_PKTNS_INITIAL; i < QUIC_TLS_PKTNS_MAX; i++) {
unsigned int tmp_pto;
if (!qc->pktns[i].tx.in_flight)
continue;
if (i == QUIC_TLS_PKTNS_01RTT) {
if (!handshake_confirmed) {
TRACE_STATE("handshake not already completed", QUIC_EV_CONN_SPTO, qc);
pktns = p;
goto out;
}
duration += qc->max_ack_delay << ql->pto_count;
}
p = &qc->pktns[i];
tmp_pto = tick_add(p->tx.time_of_last_eliciting, duration);
if (!tick_isset(lpto) || tmp_pto < lpto) {
lpto = tmp_pto;
pktns = p;
}
TRACE_DEVEL("pktns", QUIC_EV_CONN_SPTO, qc, p);
}
out:
if (pto)
*pto = lpto;
TRACE_LEAVE(QUIC_EV_CONN_SPTO, qc, pktns, &duration);
return pktns;
}
/* Look for packet loss from sent packets for <qel> encryption level of a
* connection with <ctx> as I/O handler context. If remove is true, remove them from
* their tree if deemed as lost or set the <loss_time> value the packet number
* space if any not deemed lost.
* Should be called after having received an ACK frame with newly acknowledged
* packets or when the the loss detection timer has expired.
* Always succeeds.
*/
void qc_packet_loss_lookup(struct quic_pktns *pktns, struct quic_conn *qc,
struct list *lost_pkts)
{
struct eb_root *pkts;
struct eb64_node *node;
struct quic_loss *ql;
unsigned int loss_delay;
TRACE_ENTER(QUIC_EV_CONN_PKTLOSS, qc, pktns);
pkts = &pktns->tx.pkts;
pktns->tx.loss_time = TICK_ETERNITY;
if (eb_is_empty(pkts))
goto out;
ql = &qc->path->loss;
loss_delay = QUIC_MAX(ql->latest_rtt, ql->srtt >> 3);
loss_delay = QUIC_MAX(loss_delay, MS_TO_TICKS(QUIC_TIMER_GRANULARITY)) *
QUIC_LOSS_TIME_THRESHOLD_MULTIPLICAND / QUIC_LOSS_TIME_THRESHOLD_DIVISOR;
node = eb64_first(pkts);
while (node) {
struct quic_tx_packet *pkt;
int64_t largest_acked_pn;
unsigned int loss_time_limit, time_sent;
pkt = eb64_entry(&node->node, struct quic_tx_packet, pn_node);
largest_acked_pn = pktns->rx.largest_acked_pn;
node = eb64_next(node);
if ((int64_t)pkt->pn_node.key > largest_acked_pn)
break;
time_sent = pkt->time_sent;
loss_time_limit = tick_add(time_sent, loss_delay);
if (tick_is_le(loss_time_limit, now_ms) ||
(int64_t)largest_acked_pn >= pkt->pn_node.key + QUIC_LOSS_PACKET_THRESHOLD) {
eb64_delete(&pkt->pn_node);
LIST_APPEND(lost_pkts, &pkt->list);
HA_ATOMIC_INC(&qc->prx_counters->lost_pkt);
}
else {
if (tick_isset(pktns->tx.loss_time))
pktns->tx.loss_time = tick_first(pktns->tx.loss_time, loss_time_limit);
else
pktns->tx.loss_time = loss_time_limit;
break;
}
}
out:
TRACE_LEAVE(QUIC_EV_CONN_PKTLOSS, qc, pktns, lost_pkts);
}
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