From 6636db242bad3563406048807b4670f9fabf72a7 Mon Sep 17 00:00:00 2001
From: beyondkmp <beyondkmp@gmail.com>
Date: Mon, 3 Dec 2018 23:27:00 +0800
Subject: [PATCH] Feature: add http/https [connect] proxy (#52)

---
 adapters/outbound/http.go | 148 ++++++++++++++++++++++++++++++++++++++
 config/config.go          |   7 ++
 constant/adapters.go      |   3 +
 3 files changed, 158 insertions(+)
 create mode 100644 adapters/outbound/http.go

diff --git a/adapters/outbound/http.go b/adapters/outbound/http.go
new file mode 100644
index 0000000..8938aa8
--- /dev/null
+++ b/adapters/outbound/http.go
@@ -0,0 +1,148 @@
+package adapters
+
+import (
+	"bufio"
+	"bytes"
+	"crypto/tls"
+	"encoding/base64"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+	"strconv"
+
+	C "github.com/Dreamacro/clash/constant"
+)
+
+// HTTPAdapter is a proxy adapter
+type HTTPAdapter struct {
+	conn net.Conn
+}
+
+// Close is used to close connection
+func (ha *HTTPAdapter) Close() {
+	ha.conn.Close()
+}
+
+func (ha *HTTPAdapter) Conn() net.Conn {
+	return ha.conn
+}
+
+type Http struct {
+	addr           string
+	name           string
+	user           string
+	pass           string
+	tls            bool
+	skipCertVerify bool
+	tlsConfig      *tls.Config
+}
+
+type HttpOption struct {
+	Name           string `proxy:"name"`
+	Server         string `proxy:"server"`
+	Port           int    `proxy:"port"`
+	UserName       string `proxy:"username,omitempty"`
+	Password       string `proxy:"password,omitempty"`
+	TLS            bool   `proxy:"tls,omitempty"`
+	SkipCertVerify bool   `proxy:"skip-cert-verify,omitempty"`
+}
+
+func (h *Http) Name() string {
+	return h.name
+}
+
+func (h *Http) Type() C.AdapterType {
+	return C.Http
+}
+
+func (h *Http) Generator(metadata *C.Metadata) (adapter C.ProxyAdapter, err error) {
+	c, err := net.DialTimeout("tcp", h.addr, tcpTimeout)
+	if err == nil && h.tls {
+		cc := tls.Client(c, h.tlsConfig)
+		err = cc.Handshake()
+		c = cc
+	}
+
+	if err != nil {
+		return nil, fmt.Errorf("%s connect error", h.addr)
+	}
+	tcpKeepAlive(c)
+	if err := h.shakeHand(metadata, c); err != nil {
+		return nil, err
+	}
+
+	return &HTTPAdapter{conn: c}, nil
+}
+
+func (h *Http) shakeHand(metadata *C.Metadata, rw io.ReadWriter) error {
+	var buf bytes.Buffer
+	var err error
+
+	buf.WriteString("CONNECT ")
+	buf.WriteString(net.JoinHostPort(metadata.Host, metadata.Port))
+	buf.WriteString(" HTTP/1.1\r\n")
+	buf.WriteString("Proxy-Connection: Keep-Alive\r\n")
+
+	if h.user != "" && h.pass != "" {
+		auth := h.user + ":" + h.pass
+		buf.WriteString("Proxy-Authorization: Basic " + base64.StdEncoding.EncodeToString([]byte(auth)) + "\r\n")
+	}
+	// header ended
+	buf.WriteString("\r\n")
+
+	_, err = rw.Write(buf.Bytes())
+	if err != nil {
+		return err
+	}
+
+	var req http.Request
+	resp, err := http.ReadResponse(bufio.NewReader(rw), &req)
+	if err != nil {
+		return err
+	}
+
+	if resp.StatusCode == 200 {
+		return nil
+	}
+
+	if resp.StatusCode == 407 {
+		return errors.New("HTTP need auth")
+	}
+
+	if resp.StatusCode == 405 {
+		return errors.New("CONNECT method not allowed by proxy")
+	}
+	return fmt.Errorf("can not connect remote err code: %d", resp.StatusCode)
+}
+
+func (h *Http) MarshalJSON() ([]byte, error) {
+	return json.Marshal(map[string]string{
+		"type": h.Type().String(),
+	})
+}
+
+func NewHttp(option HttpOption) *Http {
+	var tlsConfig *tls.Config
+	if option.TLS {
+		tlsConfig = &tls.Config{
+			InsecureSkipVerify: option.SkipCertVerify,
+			ClientSessionCache: getClientSessionCache(),
+			MinVersion:         tls.VersionTLS11,
+			MaxVersion:         tls.VersionTLS12,
+			ServerName:         option.Server,
+		}
+	}
+
+	return &Http{
+		addr:           net.JoinHostPort(option.Server, strconv.Itoa(option.Port)),
+		name:           option.Name,
+		user:           option.UserName,
+		pass:           option.Password,
+		tls:            option.TLS,
+		skipCertVerify: option.SkipCertVerify,
+		tlsConfig:      tlsConfig,
+	}
+}
diff --git a/config/config.go b/config/config.go
index e3fdb84..d09b062 100644
--- a/config/config.go
+++ b/config/config.go
@@ -173,6 +173,13 @@ func parseProxies(cfg *rawConfig) (map[string]C.Proxy, error) {
 				break
 			}
 			proxy = adapters.NewSocks5(*socksOption)
+		case "http":
+			httpOption := &adapters.HttpOption{}
+			err = decoder.Decode(mapping, httpOption)
+			if err != nil {
+				break
+			}
+			proxy = adapters.NewHttp(*httpOption)
 		case "vmess":
 			vmessOption := &adapters.VmessOption{}
 			err = decoder.Decode(mapping, vmessOption)
diff --git a/constant/adapters.go b/constant/adapters.go
index fa0526d..6746fb5 100644
--- a/constant/adapters.go
+++ b/constant/adapters.go
@@ -12,6 +12,7 @@ const (
 	Selector
 	Shadowsocks
 	Socks5
+	Http
 	URLTest
 	Vmess
 )
@@ -50,6 +51,8 @@ func (at AdapterType) String() string {
 		return "Shadowsocks"
 	case Socks5:
 		return "Socks5"
+	case Http:
+		return "Http"
 	case URLTest:
 		return "URLTest"
 	case Vmess: