(websocket server) Handle and accept firefox browser special upgrade value (keep-alive, Upgrade)

docs/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 All changes to this project will be documented in this file.
 
+## [11.2.7] - 2021-05-27
+
+(websocket server) Handle and accept firefox browser special upgrade value (keep-alive, Upgrade)
+
 ## [11.2.6] - 2021-05-18
 
 (Windows) move EINVAL (re)definition from IXSocket.h to IXNetSystem.h (fix #289)

ixwebsocket/IXWebSocketHandshake.cpp

@@ -204,6 +204,9 @@ namespace ix
         // Check the value of the connection field
         // Some websocket servers (Go/Gorilla?) send lowercase values for the
         // connection header, so do a case insensitive comparison
+        //
+        // See https://github.com/apache/thrift/commit/7c4bdf9914fcba6c89e0f69ae48b9675578f084a
+        //
         if (!insensitiveStringCompare(headers["connection"], "Upgrade"))
         {
             std::stringstream ss;
@@ -296,7 +299,8 @@ namespace ix
             return sendErrorResponse(400, "Missing Upgrade header");
         }
 
-        if (!insensitiveStringCompare(headers["upgrade"], "WebSocket"))
+        if (!insensitiveStringCompare(headers["upgrade"], "WebSocket") &&
+            headers["Upgrade"] != "keep-alive, Upgrade") // special case for firefox
         {
             return sendErrorResponse(400,
                                      "Invalid Upgrade header, "

ixwebsocket/IXWebSocketVersion.h

@@ -6,4 +6,4 @@
 
 #pragma once
 
-#define IX_WEBSOCKET_VERSION "11.2.6"
+#define IX_WEBSOCKET_VERSION "11.2.7"