diff src/event/quic/ngx_event_quic_ack.c @ 9081:52cddd44ec11 quic

QUIC: removed check for in-flight packets in computing PTO. The check is needed for clients in order to unblock a server due to anti-amplification limits, and it seems to make no sense for servers. See RFC 9002, A.6 and A.8 for a further explanation. This makes max_ack_delay to now always account, notably including PATH_CHALLENGE timers as noted in the last paragraph of 9000, 9.4, unlike when it was only used when there are packets in flight. While here, fixed nearby style.
author Sergey Kandaurov <pluknet@nginx.com>
date Tue, 09 May 2023 19:42:38 +0400
parents 2e51cf3ffd90
children c6db94ec3841
line wrap: on
line diff
--- a/src/event/quic/ngx_event_quic_ack.c
+++ b/src/event/quic/ngx_event_quic_ack.c
@@ -782,15 +782,11 @@ ngx_quic_pto(ngx_connection_t *c, ngx_qu
     qc = ngx_quic_get_connection(c);
 
     /* RFC 9002, Appendix A.8.  Setting the Loss Detection Timer */
+
     duration = qc->avg_rtt;
-
     duration += ngx_max(4 * qc->rttvar, NGX_QUIC_TIME_GRANULARITY);
     duration <<= qc->pto_count;
 
-    if (qc->congestion.in_flight == 0) { /* no in-flight packets */
-        return duration;
-    }
-
     if (ctx->level == ssl_encryption_application && c->ssl->handshaked) {
         duration += qc->ctp.max_ack_delay << qc->pto_count;
     }