add http connect proxy server

1 files changed, 134 insertions, 0 deletions

diff --git a/pkg/server/socket/proxy.go b/pkg/server/socket/proxy.go
new file mode 100644
index 0000000..ef14f48
--- /dev/null
+++ b/pkg/server/socket/proxy.go
@@ -0,0 +1,134 @@
+package socket
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"tunnel/pkg/http"
+	"tunnel/pkg/server/env"
+	"tunnel/pkg/server/queue"
+)
+
+type status struct {
+	code int
+	desc string
+}
+
+type proxySocket struct {
+	proto string
+}
+
+type proxyServer struct {
+	sock *proxySocket
+	addr string
+	auth string
+	wait chan status
+	env  env.Env
+	conn Conn
+}
+
+func newProxySocket(proto string) (S, error) {
+	return &proxySocket{proto}, nil
+}
+
+func (sock *proxySocket) Open(env env.Env) (Conn, error) {
+	s := &proxyServer{
+		sock: sock,
+		auth: env.GetLocal("proxy.auth"),
+		wait: make(chan status),
+		env:  env,
+	}
+
+	return s, nil
+}
+
+func (sock *proxySocket) Close() {
+}
+
+func (s *proxyServer) String() string {
+	return "proxy"
+}
+
+func (s *proxyServer) Send(wq queue.Q) error {
+	var out bytes.Buffer
+
+	status := <-s.wait
+
+	fmt.Fprintf(&out, "HTTP/1.0 %d %s\r\n", status.code, status.desc)
+	switch status.code {
+	case http.OK:
+		fmt.Fprintf(&out, "Proxy-Agent: tunnel\r\n")
+	case 407:
+		fmt.Fprintf(&out, "Proxy-Authenticate: Basic realm=\"tunnel\"\r\n")
+		fallthrough
+	default:
+		fmt.Fprintf(&out, "Server: tunnel\r\n")
+		fmt.Fprintf(&out, "Connection: close\r\n")
+	}
+	fmt.Fprintf(&out, "\r\n")
+
+	wq <- out.Bytes()
+
+	if status.code != http.OK {
+		return nil
+	}
+
+	return s.conn.Send(wq)
+}
+
+func (s *proxyServer) initConn(addr string) error {
+	dial, err := newDialSocket(s.sock.proto, addr)
+	if err != nil {
+		return err
+	}
+
+	conn, err := dial.Open(s.env)
+	if err != nil {
+		dial.Close()
+		return err
+	}
+
+	s.conn = conn
+
+	return nil
+}
+
+func (s *proxyServer) Recv(rq queue.Q) error {
+	req, err := http.ParseRequest(rq.Reader())
+	if err != nil {
+		s.wait <- status{400, "Bad Request"}
+		return err
+	}
+
+	if req.Method != "CONNECT" {
+		s.wait <- status{400, "Bad Request"}
+		return errors.New("bad method")
+	}
+
+	if s.auth != "" {
+		if auth, ok := req.Header["Proxy-Authorization"]; !ok {
+			s.wait <- status{407, "Proxy Authentication Required"}
+			return errors.New("auth required")
+		} else if !http.BasicAuthCheck(s.auth, auth) {
+			s.wait <- status{401, "Unauthorized"}
+			return errors.New("auth failed")
+		}
+	}
+
+	if err := s.initConn(req.URI); err != nil {
+		s.wait <- status{500, "Unable to connect"}
+		return err
+	}
+
+	s.wait <- status{200, "Connection established"}
+
+	return s.conn.Recv(rq)
+}
+
+func (s *proxyServer) Close() (err error) {
+	if s.conn != nil {
+		err = s.conn.Close()
+	}
+
+	return
+}