Merge branch 'develop', version 0.7.4

CHANGELOG

@@ -1,3 +1,8 @@
+0.7.4 (2013-07-15)
+    * Fix adding extra connection header for client request with both
+      "Proxy-Connection" and "Connection" headers
+    * Ignore UTF-8 BOM in config file
+
 0.7.3 (2013-07-10)
     * Handle 100-continue: do not forward expect header from client, ignore 100
       continue response replied by some web servers

README.md

@@ -2,7 +2,7 @@
 
 COW 是一个利用二级代理自动化穿越防火墙的 HTTP 代理服务器。它能自动检测被墙网站，仅对这些网站使用二级代理。
 
-当前版本：0.7.3 [CHANGELOG](CHANGELOG)
+当前版本：0.7.4 [CHANGELOG](CHANGELOG)
 [![Build Status](https://travis-ci.org/cyfdecyf/cow.png?branch=master)](https://travis-ci.org/cyfdecyf/cow)
 
 **欢迎在 develop branch 进行开发并发送 pull request :)**
@@ -112,6 +112,7 @@ COW 默认配置下检测到被墙后，过两分钟再次尝试直连也是为
 Bug reporter:
 
 GitHub users: glacjay, trawor, Blaskyy, lucifer9, zellux, xream, hieixu, fantasticfears, perrywky, JayXon, graminc, WingGao, polong, dallascao
+
 Twitter users: @shao222
 
 @glacjay 对 0.3 版本的 COW 提出了让它更加自动化的建议，使我重新考虑 COW 的设计目标并且改进成 0.5 版本之后的工作方式。

config.go

@@ -14,7 +14,7 @@ import (
 )
 
 const (
-	version           = "0.7.3"
+	version           = "0.7.4"
 	defaultListenAddr = "127.0.0.1:7777"
 )
 
@@ -388,6 +388,8 @@ func parseConfig(path string) {
 	}
 	defer f.Close()
 
+	IgnoreUTF8BOM(f)
+
 	fr := bufio.NewReader(f)
 
 	parser := reflect.ValueOf(configParser{})

http.go

@@ -49,7 +49,8 @@ type Request struct {
 	tryCnt    byte
 }
 
-var zeroRequest = Request{}
+// Assume keep-alive request by default.
+var zeroRequest = Request{Header: Header{ConnectionKeepAlive: true}}
 
 func (r *Request) reset() {
 	b := r.rawByte
@@ -284,8 +285,8 @@ func ParseRequestURIBytes(rawurl []byte) (*URL, error) {
 
 // headers of interest to a proxy
 // Define them as constant and use editor's completion to avoid typos.
-// Note RFC2616 only says about "Connection", no "Proxy-Connection", but firefox
-// send this header.
+// Note RFC2616 only says about "Connection", no "Proxy-Connection", but
+// Firefox and Safari send this header along with "Connection" header.
 // See more at http://homepage.ntlworld.com/jonathan.deboynepollard/FGA/web-proxy-connection-header.html
 const (
 	headerConnection         = "connection"
@@ -301,8 +302,9 @@ const (
 	headerUpgrade            = "upgrade"
 	headerExpect             = "expect"
 
-	fullHeaderConnection       = "Connection: keep-alive\r\n"
-	fullHeaderTransferEncoding = "Transfer-Encoding: chunked\r\n"
+	fullHeaderConnectionKeepAlive = "Connection: keep-alive\r\n"
+	fullHeaderConnectionClose     = "Connection: close\r\n"
+	fullHeaderTransferEncoding    = "Transfer-Encoding: chunked\r\n"
 )
 
 // Using Go's method expression
@@ -337,10 +339,15 @@ var hopByHopHeader = map[string]bool{
 
 type HeaderParserFunc func(*Header, []byte, *bytes.Buffer) error
 
+// Used by both "Connection" and "Proxy-Connection" header. COW always adds
+// connection header at the end of a request/response (in parseRequest and
+// parseResponse), no matter whether the original one has this header or not.
+// This will change the order of headers, but should be OK as RFC2616 4.2 says
+// header order is not significant. (Though general-header first is "good-
+// practice".)
 func (h *Header) parseConnection(s []byte, raw *bytes.Buffer) error {
 	ASCIIToLowerInplace(s)
-	h.ConnectionKeepAlive = bytes.Contains(s, []byte("keep-alive"))
-	raw.WriteString(fullHeaderConnection)
+	h.ConnectionKeepAlive = !bytes.Contains(s, []byte("close"))
 	return nil
 }
 
@@ -515,9 +522,10 @@ func parseRequest(c *clientConn, r *Request) (err error) {
 		errl.Printf("Parsing request header: %v\n", err)
 		return err
 	}
-	if !r.ConnectionKeepAlive {
-		// Always add one connection header for request
-		r.raw.WriteString(fullHeaderConnection)
+	if r.ConnectionKeepAlive {
+		r.raw.WriteString(fullHeaderConnectionKeepAlive)
+	} else {
+		r.raw.WriteString(fullHeaderConnectionClose)
 	}
 	// The spec says proxy must add Via header. polipo disables this by
 	// default, and I don't want to let others know the user is using COW, so
@@ -615,10 +623,14 @@ func parseResponse(sv *serverConn, r *Request, rp *Response) (err error) {
 	if !rp.ConnectionKeepAlive && !rp.Chunking && rp.ContLen == -1 {
 		rp.raw.WriteString("Transfer-Encoding: chunked\r\n")
 	}
-	if !rp.ConnectionKeepAlive {
-		rp.raw.WriteString("Connection: keep-alive\r\n")
+	// Whether COW should respond with keep-alive depends on client request,
+	// not server response.
+	if r.ConnectionKeepAlive {
+		rp.raw.WriteString(fullHeaderConnectionKeepAlive)
+		rp.raw.WriteString(fullKeepAliveHeader)
+	} else {
+		rp.raw.WriteString(fullHeaderConnectionClose)
 	}
-	rp.raw.WriteString(keepAliveHeader)
 	rp.raw.WriteString(CRLF)
 
 	return nil

http_test.go

@@ -88,10 +88,10 @@ func TestParseHeader(t *testing.T) {
 		header *Header
 	}{
 		{"content-length: 64\r\nConnection: keep-alive\r\n\r\n",
-			"content-length: 64\r\nConnection: keep-alive\r\n",
+			"content-length: 64\r\n",
 			&Header{ContLen: 64, Chunking: false, ConnectionKeepAlive: true}},
 		{"Connection: keep-alive\r\nKeep-Alive: timeout=10\r\nTransfer-Encoding: chunked\r\nTE: trailers\r\n\r\n",
-			"Connection: keep-alive\r\nTransfer-Encoding: chunked\r\n",
+			"Transfer-Encoding: chunked\r\n",
 			&Header{ContLen: -1, Chunking: true, ConnectionKeepAlive: true,
 				KeepAlive: 10 * time.Second}},
 		/*

install-cow.sh

@@ -1,6 +1,6 @@
 #!/bin/bash
 
-version=0.7.3
+version=0.7.4
 
 arch=`uname -m`
 case $arch in

proxy.go

@@ -37,7 +37,7 @@ var httpBuf = leakybuf.NewLeakyBuf(512, httpBufSize)
 // very conservative and easy to cause problem if we are not careful.)
 const clientConnTimeout = 5 * time.Second
 const clientMaxTimeoutCnt = 2
-const keepAliveHeader = "Keep-Alive: timeout=10\r\n"
+const fullKeepAliveHeader = "Keep-Alive: timeout=10\r\n"
 
 // Remove idle server connection every cleanServerInterval second.
 const cleanServerInterval = 5 * time.Second

util.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"bytes"
 	"crypto/md5"
 	"errors"
 	"fmt"
@@ -504,3 +505,22 @@ func stringHash(s string) (hash uint64) {
 	}
 	return
 }
+
+// IgnoreUTF8BOM consumes UTF-8 encoded BOM character if present in the file.
+func IgnoreUTF8BOM(f *os.File) error {
+	bom := make([]byte, 3)
+	n, err := f.Read(bom)
+	if err != nil {
+		return err
+	}
+	if n != 3 {
+		return nil
+	}
+	if bytes.Equal(bom, []byte{0xEF, 0xBB, 0xBF}) {
+		debug.Println("UTF-8 BOM found")
+		return nil
+	}
+	// No BOM found, seek back
+	_, err = f.Seek(-3, 1)
+	return err
+}