From 9336e7d9af31e11d764f464e5c30a867d408b242 Mon Sep 17 00:00:00 2001
From: Alex Hultman <alexhultman@gmail.com>
Date: Wed, 10 Jun 2020 22:33:09 +0200
Subject: [PATCH] Stricter PROXY/HTTP detection

---
 src/ProxyParser.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/ProxyParser.h b/src/ProxyParser.h
index 9dc7836..aee2ac1 100644
--- a/src/ProxyParser.h
+++ b/src/ProxyParser.h
@@ -94,13 +94,13 @@ public:
     /* Returns [done, consumed] where done = false on failure */
     std::pair<bool, unsigned int> parse(std::string_view data) {
 
-        /* We require at least one byte to be done */
-        if (!data.length()) {
+        /* We require at least four bytes to determine protocol */
+        if (data.length() < 4) {
             return {false, 0};
         }
 
-        /* HTTP does not start with \r, but PROXY always does */
-        if (data[0] != '\r') {
+        /* HTTP can never start with "\r\n\r\n", but PROXY always does */
+        if (memcmp(data.data(), "\r\n\r\n", 4)) {
             /* This is HTTP, so be done */
             return {true, 0};
         }