diff --git a/protocol/client.go b/protocol/client.go
index f6665fbece45ff0f9303503440d1f8808b5315ed..a5fd750f1c755dcbda1264f56a16376baade0928 100644
--- a/protocol/client.go
+++ b/protocol/client.go
@@ -4,7 +4,9 @@ import (
"bytes"
"encoding/binary"
"fmt"
+ "github.com/bolkedebruin/rdpgw/transport"
"io"
+ "net"
)
const (
@@ -17,6 +19,8 @@ type ClientConfig struct {
SmartCardAuth bool
PAAToken string
NTLMAuth bool
+ GatewayConn transport.Transport
+ LocalConn net.Conn
}
func (c *ClientConfig) handshakeRequest() []byte {
@@ -147,4 +151,39 @@ func (c *ClientConfig) tunnelAuthResponse(data []byte) (flags uint32, timeout ui
}
return
-}
\ No newline at end of file
+}
+
+func (c *ClientConfig) channelRequest(server string, port uint16) []byte {
+ utf16server := EncodeUTF16(server)
+
+ buf := new(bytes.Buffer)
+ binary.Write(buf, binary.LittleEndian, []byte{0x01}) // amount of server names
+ binary.Write(buf, binary.LittleEndian, []byte{0x00}) // amount of alternate server names (range 0-3)
+ binary.Write(buf, binary.LittleEndian, uint16(port))
+ binary.Write(buf, binary.LittleEndian, uint16(3)) // protocol, must be 3
+
+ binary.Write(buf, binary.LittleEndian, uint16(len(utf16server)))
+ buf.Write(utf16server)
+
+ return createPacket(PKT_TYPE_CHANNEL_CREATE, buf.Bytes())
+}
+
+func (c *ClientConfig) channelResponse(data []byte) (channelId uint32, err error) {
+ var errorCode uint32
+ var fields uint16
+
+ r := bytes.NewReader(data)
+ binary.Read(r, binary.LittleEndian, &errorCode)
+ binary.Read(r, binary.LittleEndian, &fields)
+ r.Seek(2, io.SeekCurrent)
+
+ if (fields & HTTP_CHANNEL_RESPONSE_FIELD_CHANNELID) == HTTP_CHANNEL_RESPONSE_FIELD_CHANNELID {
+ binary.Read(r, binary.LittleEndian, &channelId)
+ }
+
+ if errorCode > 0 {
+ return 0, fmt.Errorf("channel response error %d", errorCode)
+ }
+
+ return channelId, nil
+}
diff --git a/protocol/common.go b/protocol/common.go
index 662a8466fb92d03c08a9fb17ede4f28b689ef18a..6644e3b581a6f681335c1764ab27f7c22cdd8100 100644
--- a/protocol/common.go
+++ b/protocol/common.go
@@ -4,7 +4,10 @@ import (
"bytes"
"encoding/binary"
"errors"
+ "github.com/bolkedebruin/rdpgw/transport"
"io"
+ "log"
+ "net"
)
func createPacket(pktType uint16, data []byte) (packet []byte) {
@@ -34,4 +37,35 @@ func readHeader(data []byte) (packetType uint16, size uint32, packet []byte, err
return packetType, size, data[8:], nil
}
+// sends data wrapped inside the rdpgw protocol
+func forward(in net.Conn, out transport.Transport) {
+ defer in.Close()
+
+ b1 := new(bytes.Buffer)
+ buf := make([]byte, 4086)
+
+ for {
+ n, err := in.Read(buf)
+ if err != nil {
+ log.Printf("Error reading from local conn %s", err)
+ break
+ }
+ binary.Write(b1, binary.LittleEndian, uint16(n))
+ b1.Write(buf[:n])
+ out.WritePacket(createPacket(PKT_TYPE_DATA, b1.Bytes()))
+ b1.Reset()
+ }
+}
+
+// receive data from the wire, unwrap and forward to the client
+func receive(data []byte, out net.Conn) {
+ buf := bytes.NewReader(data)
+
+ var cblen uint16
+ binary.Read(buf, binary.LittleEndian, &cblen)
+ pkt := make([]byte, cblen)
+ binary.Read(buf, binary.LittleEndian, &pkt)
+
+ out.Write(pkt)
+}
diff --git a/protocol/protocol_test.go b/protocol/protocol_test.go
index 20bdc98a50122c87b17e2aef9a0b8983de6bbe07..ed20f90c8901faa1ac4b979fceb2a3125ecc164f 100644
--- a/protocol/protocol_test.go
+++ b/protocol/protocol_test.go
@@ -14,6 +14,8 @@ const (
TunnelCreateResponseLen = HeaderLen + 18
TunnelAuthLen = HeaderLen + 2 // + dynamic
TunnelAuthResponseLen = HeaderLen + 16
+ ChannelCreateLen = HeaderLen + 8 // + dynamic
+ ChannelResponseLen = HeaderLen + 12
)
func verifyPacketHeader(data []byte, expPt uint16, expSize uint32) (uint16, uint32, []byte, error) {
@@ -162,3 +164,44 @@ func TestTunnelAuth(t *testing.T) {
timeout, hc.IdleTimeout)
}
}
+
+func TestChannelCreation(t *testing.T) {
+ client := ClientConfig{}
+ s := &SessionInfo{}
+ hc := &ServerConf{
+ TokenAuth: true,
+ IdleTimeout: 10,
+ RedirectFlags: RedirectFlags{
+ Clipboard: true,
+ },
+ }
+ h := NewServer(s, hc)
+ server := "test_server"
+ port := uint16(3389)
+
+ data := client.channelRequest(server, port)
+ _, _, pkt, err := verifyPacketHeader(data, PKT_TYPE_CHANNEL_CREATE, uint32(ChannelCreateLen+len(server)*2))
+ if err != nil {
+ t.Fatalf("verifyHeader failed: %s", err)
+ }
+ hServer, hPort := h.channelRequest(pkt)
+ if hServer != server {
+ t.Fatalf("channelRequest failed got server %s, expected %s", hServer, server)
+ }
+ if hPort != port {
+ t.Fatalf("channelRequest failed got port %d, expected %d", hPort, port)
+ }
+
+ data = h.channelResponse()
+ _, _, pkt, err = verifyPacketHeader(data, PKT_TYPE_CHANNEL_RESPONSE, uint32(ChannelResponseLen))
+ if err != nil {
+ t.Fatalf("verifyHeader failed: %s", err)
+ }
+ channelId, err := client.channelResponse(pkt)
+ if err != nil {
+ t.Fatalf("channelResponse failed: %s", err)
+ }
+ if channelId < 1 {
+ t.Fatalf("channelResponse failed got channeld id %d, expected > 0", channelId)
+ }
+}
\ No newline at end of file
diff --git a/protocol/server.go b/protocol/server.go
index ba946b7f7245a0ef29c8323cf8b3f851111592f3..0e59535f985f72b8ac2b73f583ab20997f6f8cda 100644
--- a/protocol/server.go
+++ b/protocol/server.go
@@ -148,7 +148,7 @@ func (s *Server) Process(ctx context.Context) error {
// Make sure to start the flow from the RDP server first otherwise connections
// might hang eventually
- go s.sendDataPacket()
+ go forward(s.Remote, s.Session.TransportOut)
s.State = SERVER_STATE_CHANNEL_CREATE
case PKT_TYPE_DATA:
if s.State < SERVER_STATE_CHANNEL_CREATE {
@@ -156,7 +156,7 @@ func (s *Server) Process(ctx context.Context) error {
return errors.New("wrong state")
}
s.State = SERVER_STATE_OPENED
- s.forwardDataPacket(pkt)
+ receive(pkt, s.Remote)
case PKT_TYPE_KEEPALIVE:
// keepalives can be received while the channel is not open yet
if s.State < SERVER_STATE_CHANNEL_CREATE {
@@ -357,34 +357,6 @@ func (s *Server) channelResponse() []byte {
return createPacket(PKT_TYPE_CHANNEL_RESPONSE, buf.Bytes())
}
-func (s *Server) forwardDataPacket(data []byte) {
- buf := bytes.NewReader(data)
-
- var cblen uint16
- binary.Read(buf, binary.LittleEndian, &cblen)
- pkt := make([]byte, cblen)
- binary.Read(buf, binary.LittleEndian, &pkt)
-
- s.Remote.Write(pkt)
-}
-
-func (s *Server) sendDataPacket() {
- defer s.Remote.Close()
- b1 := new(bytes.Buffer)
- buf := make([]byte, 4086)
- for {
- n, err := s.Remote.Read(buf)
- binary.Write(b1, binary.LittleEndian, uint16(n))
- if err != nil {
- log.Printf("Error reading from conn %s", err)
- break
- }
- b1.Write(buf[:n])
- s.Session.TransportOut.WritePacket(createPacket(PKT_TYPE_DATA, b1.Bytes()))
- b1.Reset()
- }
-}
-
func makeRedirectFlags(flags RedirectFlags) int {
var redir = 0