From: Frédéric Lécaille <flecaille@haproxy.com>
Date: Fri, 10 Feb 2023 13:46:39 +0000 (+0100)
Subject: MINOR: quic: Make qc_dgrams_retransmit() return a status.
X-Git-Tag: v2.8-dev5~177
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e1738df4688b0b44aa62583f311bb1f81e151d9f;p=thirdparty%2Fhaproxy.git

MINOR: quic: Make qc_dgrams_retransmit() return a status.

This is very helpful during retranmission when receiving ICMP port unreachable
errors after the peer has left. This is the unique case at prevent where
qc_send_hdshk_pkts() or qc_send_app_probing() may fail (when they call
qc_send_ppkts() which fails with ECONNREFUSED as errno).

Also make the callers qc_dgrams_retransmit() stop their packet process. This
is the case of quic_conn_app_io_cb() and quic_conn_io_cb().

This modifications stops definitively any packet processing when receiving
ICMP port unreachable errors.

Must be backported to 2.7.
---

diff --git a/src/quic_conn.c b/src/quic_conn.c
index 0de12f3543..a44c28d057 100644
--- a/src/quic_conn.c
+++ b/src/quic_conn.c
@@ -4320,9 +4320,12 @@ int qc_send_hdshk_pkts(struct quic_conn *qc, int old_data,
 	return status;
 }
 
-/* Retransmit up to two datagrams depending on packet number space */
-static void qc_dgrams_retransmit(struct quic_conn *qc)
+/* Retransmit up to two datagrams depending on packet number space.
+ * Return 0 when failed, 0 if not.
+ */
+static int qc_dgrams_retransmit(struct quic_conn *qc)
 {
+	int ret = 0;
 	struct quic_enc_level *iqel = &qc->els[QUIC_TLS_ENC_LEVEL_INITIAL];
 	struct quic_enc_level *hqel = &qc->els[QUIC_TLS_ENC_LEVEL_HANDSHAKE];
 	struct quic_enc_level *aqel = &qc->els[QUIC_TLS_ENC_LEVEL_APP];
@@ -4343,8 +4346,9 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 				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);
+				if (!qc_send_hdshk_pkts(qc, 1, QUIC_TLS_ENC_LEVEL_INITIAL, &ifrms,
+				                        QUIC_TLS_ENC_LEVEL_HANDSHAKE, &hfrms))
+					goto leave;
 				/* Put back unsent frames in their packet number spaces */
 				LIST_SPLICE(&iqel->pktns->tx.frms, &ifrms);
 				LIST_SPLICE(&hqel->pktns->tx.frms, &hfrms);
@@ -4367,8 +4371,10 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 				TRACE_DEVEL("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &frms1);
 				if (!LIST_ISEMPTY(&frms1)) {
 					hqel->pktns->tx.pto_probe = 1;
-					qc_send_hdshk_pkts(qc, 1, QUIC_TLS_ENC_LEVEL_HANDSHAKE, &frms1,
-					                   QUIC_TLS_ENC_LEVEL_NONE, NULL);
+					if (!qc_send_hdshk_pkts(qc, 1, QUIC_TLS_ENC_LEVEL_HANDSHAKE, &frms1,
+					                        QUIC_TLS_ENC_LEVEL_NONE, NULL))
+						goto leave;
+
 					/* Put back unsent frames into their packet number spaces */
 					LIST_SPLICE(&hqel->pktns->tx.frms, &frms1);
 				}
@@ -4387,13 +4393,16 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 			TRACE_PROTO("Avail. ack eliciting frames", QUIC_EV_CONN_FRMLIST, qc, &frms2);
 			if (!LIST_ISEMPTY(&frms1)) {
 				aqel->pktns->tx.pto_probe = 1;
-				qc_send_app_probing(qc, &frms1);
+				if (!qc_send_app_probing(qc, &frms1))
+					goto leave;
+
 				/* Put back unsent frames into their packet number spaces */
 				LIST_SPLICE(&aqel->pktns->tx.frms, &frms1);
 			}
 			if (!LIST_ISEMPTY(&frms2)) {
 				aqel->pktns->tx.pto_probe = 1;
-				qc_send_app_probing(qc, &frms2);
+				if (!qc_send_app_probing(qc, &frms2))
+					goto leave;
 				/* Put back unsent frames into their packet number spaces */
 				LIST_SPLICE(&aqel->pktns->tx.frms, &frms2);
 			}
@@ -4402,7 +4411,11 @@ static void qc_dgrams_retransmit(struct quic_conn *qc)
 			aqel->pktns->flags &= ~QUIC_FL_PKTNS_PROBE_NEEDED;
 		}
 	}
+
+	ret = 1;
+ leave:
 	TRACE_LEAVE(QUIC_EV_CONN_TXPKT, qc);
+	return ret;
 }
 
 /* QUIC connection packet handler task (post handshake) */
@@ -4423,7 +4436,8 @@ struct task *quic_conn_app_io_cb(struct task *t, void *context, unsigned int sta
 	if (qc->flags & QUIC_FL_CONN_RETRANS_NEEDED) {
 		TRACE_STATE("retransmission needed", QUIC_EV_CONN_IO_CB, qc);
 		qc->flags &= ~QUIC_FL_CONN_RETRANS_NEEDED;
-		qc_dgrams_retransmit(qc);
+		if (!qc_dgrams_retransmit(qc))
+			goto out;
 	}
 
 	if (!LIST_ISEMPTY(&qel->rx.pqpkts) && qc_qel_may_rm_hp(qc, qel))
@@ -4486,7 +4500,8 @@ struct task *quic_conn_io_cb(struct task *t, void *context, unsigned int state)
 	if (qc->flags & QUIC_FL_CONN_RETRANS_NEEDED) {
 		TRACE_DEVEL("retransmission needed", QUIC_EV_CONN_PHPKTS, qc);
 		qc->flags &= ~QUIC_FL_CONN_RETRANS_NEEDED;
-		qc_dgrams_retransmit(qc);
+		if (!qc_dgrams_retransmit(qc))
+			goto out;
 	}
 
 	ssl_err = SSL_ERROR_NONE;