From 5aa053a65fd8888a2a7c8c32ab12e0afe89ebb06 Mon Sep 17 00:00:00 2001
From: Arthur Morgan <arthur.m.v1863@gmail.com>
Date: Fri, 22 Jan 2021 07:37:55 +0800
Subject: [PATCH] Convert domain names to lowercase before matching (#195)

Co-authored-by: RPRX <63339210+rprx@users.noreply.github.com>
---
 app/dns/server.go              | 1 +
 app/router/condition.go        | 2 +-
 common/protocol/tls/sniff.go   | 2 +-
 proxy/trojan/server.go         | 2 ++
 proxy/vless/inbound/inbound.go | 2 ++
 5 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/app/dns/server.go b/app/dns/server.go
index 667b398e..82f9d23e 100644
--- a/app/dns/server.go
+++ b/app/dns/server.go
@@ -364,6 +364,7 @@ func (s *Server) lookupIPInternal(domain string, option IPOption) ([]net.IP, err
 	if domain == "" {
 		return nil, newError("empty domain name")
 	}
+	domain = strings.ToLower(domain)
 
 	// normalize the FQDN form query
 	if domain[len(domain)-1] == '.' {
diff --git a/app/router/condition.go b/app/router/condition.go
index 341cb566..8c5d1de8 100644
--- a/app/router/condition.go
+++ b/app/router/condition.go
@@ -91,7 +91,7 @@ func (m *DomainMatcher) Apply(ctx routing.Context) bool {
 	if len(domain) == 0 {
 		return false
 	}
-	return m.ApplyDomain(domain)
+	return m.ApplyDomain(strings.ToLower(domain))
 }
 
 type MultiGeoIPMatcher struct {
diff --git a/common/protocol/tls/sniff.go b/common/protocol/tls/sniff.go
index a8fec15f..f3806a05 100644
--- a/common/protocol/tls/sniff.go
+++ b/common/protocol/tls/sniff.go
@@ -102,7 +102,7 @@ func ReadClientHello(data []byte, h *SniffHeader) error {
 					return errNotClientHello
 				}
 				if nameType == 0 {
-					serverName := string(d[:nameLen])
+					serverName := strings.ToLower(string(d[:nameLen]))
 					// An SNI value may not include a
 					// trailing dot. See
 					// https://tools.ietf.org/html/rfc6066#section-3.
diff --git a/proxy/trojan/server.go b/proxy/trojan/server.go
index 6b22e49e..4871524f 100644
--- a/proxy/trojan/server.go
+++ b/proxy/trojan/server.go
@@ -412,6 +412,8 @@ func (s *Server) fallback(ctx context.Context, sid errors.ExportOption, err erro
 		newError("realName = " + name).AtInfo().WriteToLog(sid)
 		newError("realAlpn = " + alpn).AtInfo().WriteToLog(sid)
 	}
+	name = strings.ToLower(name)
+	alpn = strings.ToLower(alpn)
 
 	if len(napfb) > 1 || napfb[""] == nil {
 		if name != "" && napfb[name] == nil {
diff --git a/proxy/vless/inbound/inbound.go b/proxy/vless/inbound/inbound.go
index 264f1e1f..8766d391 100644
--- a/proxy/vless/inbound/inbound.go
+++ b/proxy/vless/inbound/inbound.go
@@ -232,6 +232,8 @@ func (h *Handler) Process(ctx context.Context, network net.Network, connection i
 				newError("realName = " + name).AtInfo().WriteToLog(sid)
 				newError("realAlpn = " + alpn).AtInfo().WriteToLog(sid)
 			}
+			name = strings.ToLower(name)
+			alpn = strings.ToLower(alpn)
 
 			if len(napfb) > 1 || napfb[""] == nil {
 				if name != "" && napfb[name] == nil {