From bfbeecdc1c23c4ba4e7697b67e4888a80b533fdb Mon Sep 17 00:00:00 2001
From: Phoenix Kahlo <kahlo.phoenix@gmail.com>
Date: Sat, 21 Dec 2024 14:46:32 -0600
Subject: [PATCH] proto: Reject RetryToken with extra bytes

This probably won't affect much, but is slightly more defensive.
---
 quinn-proto/src/token.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/quinn-proto/src/token.rs b/quinn-proto/src/token.rs
index 8419c6bbc..15cff4aa3 100644
--- a/quinn-proto/src/token.rs
+++ b/quinn-proto/src/token.rs
@@ -119,6 +119,11 @@ impl RetryToken {
         let orig_dst_cid = ConnectionId::decode_long(&mut reader)?;
         let issued = decode_unix_secs(&mut reader)?;
 
+        if !reader.is_empty() {
+            // Consider extra bytes a decoding error (it may be from an incompatible endpoint)
+            return None;
+        }
+
         Some(Self {
             address,
             orig_dst_cid,