Add dialer interface according to golang.org/x/net/proxy.

proxy/dialer.go

@@ -0,0 +1,53 @@
+package core
+
+import (
+	"net"
+	"errors"
+	"github.com/shadowsocks/go-shadowsocks2/socks"
+	"github.com/shadowsocks/go-shadowsocks2/core"
+)
+
+type ProxyDialer struct {
+	core.StreamConnCipher
+	addr string
+}
+
+func NewDialer(addr string, algo string, password string) (s *ProxyDialer, err error) {
+	cipher, err := core.PickCipher(algo, nil, password)
+	if err != nil {
+		return
+	}
+	s = new(ProxyDialer)
+	s.StreamConnCipher = cipher
+	s.addr = addr
+	return
+}
+
+func NewDialerFromKey(addr string, algo string, key []byte) (s *ProxyDialer, err error) {
+	cipher, err := core.PickCipher(algo, key, "")
+	if err != nil {
+		return
+	}
+	s = new(ProxyDialer)
+	s.StreamConnCipher = cipher
+	s.addr = addr
+	return
+}
+
+func (dialer *ProxyDialer) Dial(network, addr string) (c net.Conn, err error) {
+	target := socks.ParseAddr(addr)
+	if target == nil {
+		return nil, errors.New("Unable to parse address: " + addr)
+	}
+	conn, err := net.Dial("tcp", dialer.addr)
+	if err != nil {
+		return nil, err
+	}
+	conn.(*net.TCPConn).SetKeepAlive(true)
+	c = dialer.StreamConn(conn)
+	if _, err = c.Write(target); err != nil {
+		c.Close()
+		return nil, err
+	}
+	return
+}

proxy/dialer_test.go

@@ -0,0 +1,133 @@
+package core
+
+import (
+	"testing"
+	"net/http"
+	"golang.org/x/net/proxy"
+	"github.com/shadowsocks/go-shadowsocks2/socks"
+	"github.com/shadowsocks/go-shadowsocks2/core"
+	"io/ioutil"
+	"net"
+	"io"
+	"time"
+	"strings"
+)
+
+func TestDialerInterface(t *testing.T) {
+	var dialer proxy.Dialer
+	dialer, err := NewDialer("198.51.100.254:65534", "aes-128-gcm", "dialer-test")
+	if err != nil {
+		t.Fatal("Unable to create new dialer:", err.Error())
+		return
+	}
+	// AES-128 key is 16 bytes long.
+	// This key is just for interface testing only, so zeroKey doesn't matter.
+	zeroKey := make([]byte, 16)
+	dialer, err = NewDialerFromKey("195.51.100.254:65533", "aes-128-gcm", zeroKey)
+	if err != nil {
+		t.Fatal("Unable to create new dialer with pre-generated key:", err.Error())
+		return
+	}
+	_ = dialer
+	t.Log("Dialer interface works.")
+}
+
+func TestDialerFunctionality(t *testing.T) {
+	// First let's launch a dummy shadowsocks server.
+	ciph, err := core.PickCipher("aes-128-gcm", nil, "dialer-test")
+	if err != nil {
+		t.Fatal("Unable to pick cipher", ciph, ":", err.Error())
+		return
+	}
+	go tcpRemote("127.0.0.1:60001", ciph.StreamConn)
+	dialer, err := NewDialer("127.0.0.1:60001", "aes-128-gcm", "dialer-test")
+	if err != nil {
+		t.Fatal("Unable to create new dialer:", err.Error())
+		return
+	}
+	client := &http.Client {
+		Transport: &http.Transport {
+			Dial: dialer.Dial,
+		},
+	}
+	resp, err := client.Get("http://ifconfig.co")
+	if err != nil {
+		t.Fatal("Unable to connect ifconfig.co through shadowsocks server:", err.Error())
+		return
+	}
+	t.Log("http.Get ifconfig.co =", resp.Status)
+	body, _ := ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	ip := strings.TrimSpace(string(body))
+	t.Log("My IP address is:", ip)
+	if ipp := net.ParseIP(ip); ipp == nil {
+		t.Errorf("Responsed IP address is not a valid IP.")
+	} else {
+		t.Log("IP address looks good.")
+	}
+
+}
+
+// Code lines below are copied from main package, since go can't import main package.
+func tcpRemote(addr string, shadow func(net.Conn) net.Conn) {
+	l, err := net.Listen("tcp", addr)
+	if err != nil {
+		return
+	}
+	for {
+		c, err := l.Accept()
+		if err != nil {
+			continue
+		}
+
+		go func() {
+			defer c.Close()
+			c.(*net.TCPConn).SetKeepAlive(true)
+			c = shadow(c)
+
+			tgt, err := socks.ReadAddr(c)
+			if err != nil {
+				return
+			}
+
+			rc, err := net.Dial("tcp", tgt.String())
+			if err != nil {
+				return
+			}
+			defer rc.Close()
+			rc.(*net.TCPConn).SetKeepAlive(true)
+
+			_, _, err = relay(c, rc)
+			if err != nil {
+				if err, ok := err.(net.Error); ok && err.Timeout() {
+					return // ignore i/o timeout
+				}
+			}
+		}()
+	}
+}
+
+func relay(left, right net.Conn) (int64, int64, error) {
+	type res struct {
+		N   int64
+		Err error
+	}
+	ch := make(chan res)
+
+	go func() {
+		n, err := io.Copy(right, left)
+		right.SetDeadline(time.Now()) // wake up the other goroutine blocking on right
+		left.SetDeadline(time.Now())  // wake up the other goroutine blocking on left
+		ch <- res{n, err}
+	}()
+
+	n, err := io.Copy(left, right)
+	right.SetDeadline(time.Now()) // wake up the other goroutine blocking on right
+	left.SetDeadline(time.Now())  // wake up the other goroutine blocking on left
+	rs := <-ch
+
+	if err == nil {
+		err = rs.Err
+	}
+	return n, rs.N, err
+}