Move PROXY proto logic to its own proxyproto.go file.

service/listeners.go

@@ -15,7 +15,6 @@
 package service
 
 import (
-	"bufio"
 	"errors"
 	"fmt"
 	"io"
@@ -24,7 +23,6 @@ import (
 	"sync/atomic"
 
 	"github.com/Jigsaw-Code/outline-sdk/transport"
-	"github.com/pires/go-proxyproto"
 )
 
 // The implementations of listeners for different network types are not
@@ -139,34 +137,6 @@ func (sl *virtualStreamListener) Addr() net.Addr {
 	return sl.addr
 }
 
-// ProxyStreamListener wraps a [StreamListener] and fetches the source of the connection from the PROXY
-// protocol header string. See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt.
-type ProxyStreamListener struct {
-	StreamListener
-}
-
-// AcceptStream waits for the next incoming connection, parses the client IP from the PROXY protocol
-// header, and adds it to the connection.
-func (l *ProxyStreamListener) AcceptStream() (ClientStreamConn, error) {
-	conn, err := l.StreamListener.AcceptStream()
-	if err != nil {
-		return nil, err
-	}
-	r := bufio.NewReader(conn)
-	header, err := proxyproto.Read(r)
-	if errors.Is(err, proxyproto.ErrNoProxyProtocol) {
-		logger.Warningf("Received connection from %v without proxy header.", conn.RemoteAddr())
-		return conn, nil
-	}
-	if header == nil || err != nil {
-		return nil, fmt.Errorf("error parsing proxy header: %v", err)
-	}
-	if header.Command.IsLocal() {
-		return conn, nil
-	}
-	return &clientStreamConn{StreamConn: conn, clientAddr: header.SourceAddr}, nil
-}
-
 type packetResponse struct {
 	n    int
 	addr net.Addr

service/proxyproto.go

@@ -0,0 +1,51 @@
+// Copyright 2024 The Outline Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package service
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+
+	"github.com/pires/go-proxyproto"
+)
+
+// ProxyStreamListener wraps a [StreamListener] and fetches the source of the connection from the PROXY
+// protocol header string. See https://www.haproxy.org/download/1.8/doc/proxy-protocol.txt.
+type ProxyStreamListener struct {
+	StreamListener
+}
+
+// AcceptStream waits for the next incoming connection, parses the client IP from the PROXY protocol
+// header, and adds it to the connection.
+func (l *ProxyStreamListener) AcceptStream() (ClientStreamConn, error) {
+	conn, err := l.StreamListener.AcceptStream()
+	if err != nil {
+		return nil, err
+	}
+	r := bufio.NewReader(conn)
+	header, err := proxyproto.Read(r)
+	if errors.Is(err, proxyproto.ErrNoProxyProtocol) {
+		logger.Warningf("Received connection from %v without proxy header.", conn.RemoteAddr())
+		return conn, nil
+	}
+	if header == nil || err != nil {
+		return nil, fmt.Errorf("error parsing proxy header: %v", err)
+	}
+	if header.Command.IsLocal() {
+		return conn, nil
+	}
+	return &clientStreamConn{StreamConn: conn, clientAddr: header.SourceAddr}, nil
+}