commit d7e3b9581d0a54e19527ad761dacc8717acc08f6
author Alessandro Ghedini <alessandro@ghedini.me> Wed Jan 29 16:03:39 2020 +0000
committer Alessandro Ghedini <alessandro@ghedini.me> Thu Jan 30 14:55:22 2020 +0000
tree d7c8e6d8f193e6a226f4c61d4b61f9631041b41e
parent 819ba14d2d38737f2f88b8fb364c0b9e770a0f1d

packet: correct (over|under)flow checks on packet number decoding algorithm

See https://github.com/quicwg/base-drafts/pull/3188.

src/packet.rs

diff --git a/src/packet.rs b/src/packet.rs
index f0adad8..c9a78ac 100644
--- a/src/packet.rs
+++ b/src/packet.rs
@@ -468,11 +468,12 @@
     let pn_mask = pn_win - 1;
     let candidate_pn = (expected_pn & !pn_mask) | truncated_pn;
 
-    if candidate_pn + pn_hwin <= expected_pn {
+    if candidate_pn + pn_hwin <= expected_pn && candidate_pn < (1 << 62) - pn_win
+    {
         return candidate_pn + pn_win;
     }
 
-    if candidate_pn > expected_pn + pn_hwin && candidate_pn > pn_win {
+    if candidate_pn > expected_pn + pn_hwin && candidate_pn >= pn_win {
         return candidate_pn - pn_win;
     }