From b16d2e946311963e8b20be130e9c7dd66da9d544 Mon Sep 17 00:00:00 2001
From: Darien Raymond <admin@v2ray.com>
Date: Wed, 4 Jul 2018 22:26:15 +0200
Subject: [PATCH] make sure dc id is valid.

---
 proxy/mtproto/auth.go   | 2 +-
 proxy/mtproto/server.go | 3 ---
 2 files changed, 1 insertion(+), 4 deletions(-)

diff --git a/proxy/mtproto/auth.go b/proxy/mtproto/auth.go
index aee01064d..962bc1c39 100644
--- a/proxy/mtproto/auth.go
+++ b/proxy/mtproto/auth.go
@@ -22,7 +22,7 @@ type Authentication struct {
 }
 
 func (a *Authentication) DataCenterID() uint16 {
-	return (uint16(a.Header[61]) << 8) | uint16(a.Header[60])
+	return ((uint16(a.Header[61]) << 8) | uint16(a.Header[60])) % uint16(len(dcList))
 }
 
 func (a *Authentication) ApplySecret(b []byte) {
diff --git a/proxy/mtproto/server.go b/proxy/mtproto/server.go
index eba1c684f..a645d470f 100644
--- a/proxy/mtproto/server.go
+++ b/proxy/mtproto/server.go
@@ -90,9 +90,6 @@ func (s *Server) Process(ctx context.Context, network net.Network, conn internet
 	}
 
 	dcID := auth.DataCenterID()
-	if dcID >= uint16(len(dcList)) {
-		return newError("invalid data center id: ", dcID)
-	}
 
 	dest := net.Destination{
 		Network: net.Network_TCP,