Chore: split component to transport

transport/simple-obfs/http.go

@@ -0,0 +1,94 @@
+package obfs
+
+import (
+	"bytes"
+	"encoding/base64"
+	"fmt"
+	"io"
+	"math/rand"
+	"net"
+	"net/http"
+
+	"github.com/Dreamacro/clash/common/pool"
+)
+
+// HTTPObfs is shadowsocks http simple-obfs implementation
+type HTTPObfs struct {
+	net.Conn
+	host          string
+	port          string
+	buf           []byte
+	offset        int
+	firstRequest  bool
+	firstResponse bool
+}
+
+func (ho *HTTPObfs) Read(b []byte) (int, error) {
+	if ho.buf != nil {
+		n := copy(b, ho.buf[ho.offset:])
+		ho.offset += n
+		if ho.offset == len(ho.buf) {
+			pool.Put(ho.buf)
+			ho.buf = nil
+		}
+		return n, nil
+	}
+
+	if ho.firstResponse {
+		buf := pool.Get(pool.RelayBufferSize)
+		n, err := ho.Conn.Read(buf)
+		if err != nil {
+			pool.Put(buf)
+			return 0, err
+		}
+		idx := bytes.Index(buf[:n], []byte("\r\n\r\n"))
+		if idx == -1 {
+			pool.Put(buf)
+			return 0, io.EOF
+		}
+		ho.firstResponse = false
+		length := n - (idx + 4)
+		n = copy(b, buf[idx+4:n])
+		if length > n {
+			ho.buf = buf[:idx+4+length]
+			ho.offset = idx + 4 + n
+		} else {
+			pool.Put(buf)
+		}
+		return n, nil
+	}
+	return ho.Conn.Read(b)
+}
+
+func (ho *HTTPObfs) Write(b []byte) (int, error) {
+	if ho.firstRequest {
+		randBytes := make([]byte, 16)
+		rand.Read(randBytes)
+		req, _ := http.NewRequest("GET", fmt.Sprintf("http://%s/", ho.host), bytes.NewBuffer(b[:]))
+		req.Header.Set("User-Agent", fmt.Sprintf("curl/7.%d.%d", rand.Int()%54, rand.Int()%2))
+		req.Header.Set("Upgrade", "websocket")
+		req.Header.Set("Connection", "Upgrade")
+		req.Host = ho.host
+		if ho.port != "80" {
+			req.Host = fmt.Sprintf("%s:%s", ho.host, ho.port)
+		}
+		req.Header.Set("Sec-WebSocket-Key", base64.URLEncoding.EncodeToString(randBytes))
+		req.ContentLength = int64(len(b))
+		err := req.Write(ho.Conn)
+		ho.firstRequest = false
+		return len(b), err
+	}
+
+	return ho.Conn.Write(b)
+}
+
+// NewHTTPObfs return a HTTPObfs
+func NewHTTPObfs(conn net.Conn, host string, port string) net.Conn {
+	return &HTTPObfs{
+		Conn:          conn,
+		firstRequest:  true,
+		firstResponse: true,
+		host:          host,
+		port:          port,
+	}
+}