From: Frédéric Lécaille <flecaille@haproxy.com>
Date: Tue, 31 Jan 2023 16:32:06 +0000 (+0100)
Subject: MINOR: quic: When probing Handshake packet number space, also probe the Initial one
X-Git-Tag: v2.8-dev3~30
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=37ed4a3842d0f8c4a4f77c5f57b2dc1f0401a7e1;p=thirdparty%2Fhaproxy.git

MINOR: quic: When probing Handshake packet number space, also probe the Initial one

This is not really a bug fix but an improvement. When the Handshake packet number
space has been detected as needed to be probed, we should also try to probe the
Initial packet number space if there are still packets in flight. Furthermore
we should also try to send up to two datagrams.

Must be backported to 2.6 and 2.7.
---

diff --git a/src/quic_conn.c b/src/quic_conn.c
index a660eab1c1..907ee9873e 100644
--- a/src/quic_conn.c
+++ b/src/quic_conn.c
@@ -4210,16 +4210,19 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 	TRACE_ENTER(QUIC_EV_CONN_TXPKT, qc);
 
 	if (iqel->pktns->flags & QUIC_FL_PKTNS_PROBE_NEEDED) {
-		struct list ifrms = LIST_HEAD_INIT(ifrms);
-		struct list hfrms = LIST_HEAD_INIT(hfrms);
-
-		qc_prep_hdshk_fast_retrans(qc, &ifrms, &hfrms);
-		TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &ifrms);
-		TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &hfrms);
-		if (!LIST_ISEMPTY(&ifrms)) {
-			iqel->pktns->tx.pto_probe = 1;
-			if (!LIST_ISEMPTY(&hfrms)) {
-				hqel->pktns->tx.pto_probe = 1;
+		int i;
+
+		for (i = 0; i < QUIC_MAX_NB_PTO_DGRAMS; i++) {
+			struct list ifrms = LIST_HEAD_INIT(ifrms);
+			struct list hfrms = LIST_HEAD_INIT(hfrms);
+
+			qc_prep_hdshk_fast_retrans(qc, &ifrms, &hfrms);
+			TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &ifrms);
+			TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &hfrms);
+			if (!LIST_ISEMPTY(&ifrms)) {
+				iqel->pktns->tx.pto_probe = 1;
+				if (!LIST_ISEMPTY(&hfrms))
+					hqel->pktns->tx.pto_probe = 1;
 				qc_send_hdshk_pkts(qc, 1, QUIC_TLS_ENC_LEVEL_INITIAL, &ifrms,
 				                   QUIC_TLS_ENC_LEVEL_HANDSHAKE, &hfrms);
 				/* Put back unsent frames in their packet number spaces */
@@ -4227,27 +4230,10 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 				LIST_SPLICE(&hqel->pktns->tx.frms, &hfrms);
 			}
 		}
-		if (hqel->pktns->flags & QUIC_FL_PKTNS_PROBE_NEEDED) {
-			/* This list has potentially been already used and spliced
-			 * to another one attached to the connection. We must reinitialize it.
-			 */
-			LIST_INIT(&hfrms);
-			qc_prep_fast_retrans(qc, hqel, &hfrms, NULL);
-			TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &hfrms);
-			if (!LIST_ISEMPTY(&hfrms)) {
-				hqel->pktns->tx.pto_probe = 1;
-				qc_send_hdshk_pkts(qc, 1, QUIC_TLS_ENC_LEVEL_HANDSHAKE, &hfrms,
-				                   QUIC_TLS_ENC_LEVEL_NONE, NULL);
-				/* Put back unsent frames into their packet number spaces */
-				LIST_SPLICE(&hqel->pktns->tx.frms, &hfrms);
-			}
-			TRACE_STATE("no more need to probe Handshake packet number space",
-			            QUIC_EV_CONN_TXPKT, qc);
-			hqel->pktns->flags &= ~QUIC_FL_PKTNS_PROBE_NEEDED;
-		}
 		TRACE_STATE("no more need to probe Initial packet number space",
 					QUIC_EV_CONN_TXPKT, qc);
 		iqel->pktns->flags &= ~QUIC_FL_PKTNS_PROBE_NEEDED;
+		hqel->pktns->flags &= ~QUIC_FL_PKTNS_PROBE_NEEDED;
 	}
 	else {
 		int i;
@@ -4676,6 +4662,10 @@ struct task *qc_process_timer(struct task *task, void *ctx, unsigned int state)
 			}
 			else if (pktns == &qc->pktns[QUIC_TLS_PKTNS_HANDSHAKE]) {
 				TRACE_STATE("needs to probe Handshake packet number space", QUIC_EV_CONN_TXPKT, qc);
+				if (qc->pktns[QUIC_TLS_PKTNS_INITIAL].tx.in_flight) {
+					qc->pktns[QUIC_TLS_PKTNS_INITIAL].flags |= QUIC_FL_PKTNS_PROBE_NEEDED;
+					TRACE_STATE("needs to probe Initial packet number space", QUIC_EV_CONN_TXPKT, qc);
+				}
 			}
 			else if (pktns == &qc->pktns[QUIC_TLS_PKTNS_01RTT]) {
 				TRACE_STATE("needs to probe 01RTT packet number space", QUIC_EV_CONN_TXPKT, qc);