Merge pull request #105 from sheerun/sheerun/permissions

Implement whitelisting on socks, ssh, and http2

cmd/gost/main.go

@@ -65,6 +65,8 @@ func main() {
 			glog.Fatal(err)
 		}
 
+		glog.Info(serverNode)
+
 		wg.Add(1)
 		go func(node gost.ProxyNode) {
 			defer wg.Done()

http.go

@@ -5,14 +5,15 @@ import (
 	"crypto/tls"
 	"encoding/base64"
 	"errors"
-	"github.com/ginuerzh/pht"
-	"github.com/golang/glog"
-	"golang.org/x/net/http2"
 	"io"
 	"net"
 	"net/http"
 	"net/http/httputil"
 	"time"
+
+	"github.com/ginuerzh/pht"
+	"github.com/golang/glog"
+	"golang.org/x/net/http2"
 )
 
 type HttpServer struct {
@@ -75,6 +76,11 @@ func (s *HttpServer) HandleRequest(req *http.Request) {
 		return
 	}
 
+	if !s.Base.Node.Can("tcp", req.Host) {
+		glog.Errorf("Unauthorized to tcp connect to %s", req.Host)
+		return
+	}
+
 	c, err := s.Base.Chain.Dial(req.Host)
 	if err != nil {
 		glog.V(LWARNING).Infof("[http] %s -> %s : %s", s.conn.RemoteAddr(), req.Host, err)
@@ -184,6 +190,11 @@ func (s *Http2Server) HandleRequest(w http.ResponseWriter, req *http.Request) {
 
 	w.Header().Set("Proxy-Agent", "gost/"+Version)
 
+	if !s.Base.Node.Can("tcp", target) {
+		glog.Errorf("Unauthorized to tcp connect to %s", target)
+		return
+	}
+
 	// HTTP2 as transport
 	if req.Header.Get("Proxy-Switch") == "gost" {
 		conn, err := s.Upgrade(w, req)

node.go

@@ -19,6 +19,8 @@ type ProxyNode struct {
 	Transport  string          // transport: ws/wss/tls/http2/tcp/udp/rtcp/rudp
 	Remote     string          // remote address, used by tcp/udp port forwarding
 	Users      []*url.Userinfo // authentication for proxy
+	Whitelist  *Permissions
+	Blacklist  *Permissions
 	values     url.Values
 	serverName string
 	conn       net.Conn
@@ -36,12 +38,36 @@ func ParseProxyNode(s string) (node ProxyNode, err error) {
 		return
 	}
 
+	query := u.Query()
+
 	node = ProxyNode{
 		Addr:       u.Host,
-		values:     u.Query(),
+		values:     query,
 		serverName: u.Host,
 	}
 
+	if query.Get("whitelist") != "" {
+		node.Whitelist, err = ParsePermissions(query.Get("whitelist"))
+
+		if err != nil {
+			glog.Fatal(err)
+		}
+	} else {
+		// By default allow for everyting
+		node.Whitelist, _ = ParsePermissions("*:*:*")
+	}
+
+	if query.Get("blacklist") != "" {
+		node.Blacklist, err = ParsePermissions(query.Get("blacklist"))
+
+		if err != nil {
+			glog.Fatal(err)
+		}
+	} else {
+		// By default block nothing
+		node.Blacklist, _ = ParsePermissions("")
+	}
+
 	if u.User != nil {
 		node.Users = append(node.Users, u.User)
 	}
@@ -126,6 +152,24 @@ func (node *ProxyNode) Get(key string) string {
 	return node.values.Get(key)
 }
 
+func (node *ProxyNode) Can(action string, addr string) bool {
+	host, strport, err := net.SplitHostPort(addr)
+
+	if err != nil {
+		return false
+	}
+
+	port, err := strconv.Atoi(strport)
+
+	if err != nil {
+		return false
+	}
+
+	glog.V(LDEBUG).Infof("Can action: %s, host: %s, port %d", action, host, port)
+
+	return node.Whitelist.Can(action, host, port) && !node.Blacklist.Can(action, host, port)
+}
+
 func (node *ProxyNode) getBool(key string) bool {
 	s := node.Get(key)
 	if b, _ := strconv.ParseBool(s); b {
@@ -162,5 +206,5 @@ func (node *ProxyNode) keyFile() string {
 }
 
 func (node ProxyNode) String() string {
-	return fmt.Sprintf("transport: %s, protocol: %s, addr: %s", node.Transport, node.Protocol, node.Addr)
+	return fmt.Sprintf("transport: %s, protocol: %s, addr: %s, whitelist: %v, blacklist: %v", node.Transport, node.Protocol, node.Addr, node.Whitelist, node.Blacklist)
 }

node_test.go

+package gost
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNodeDefaultWhitelist(t *testing.T) {
+	assert := assert.New(t)
+
+	node, _ := ParseProxyNode("http2://localhost:8000")
+
+	assert.True(node.Can("connect", "google.pl:80"))
+	assert.True(node.Can("connect", "google.pl:443"))
+	assert.True(node.Can("connect", "google.pl:22"))
+	assert.True(node.Can("bind", "google.pl:80"))
+	assert.True(node.Can("bind", "google.com:80"))
+}
+
+func TestNodeWhitelist(t *testing.T) {
+	assert := assert.New(t)
+
+	node, _ := ParseProxyNode("http2://localhost:8000?whitelist=connect:google.pl:80,443")
+
+	assert.True(node.Can("connect", "google.pl:80"))
+	assert.True(node.Can("connect", "google.pl:443"))
+	assert.False(node.Can("connect", "google.pl:22"))
+	assert.False(node.Can("bind", "google.pl:80"))
+	assert.False(node.Can("bind", "google.com:80"))
+}
+
+func TestNodeBlacklist(t *testing.T) {
+	assert := assert.New(t)
+
+	node, _ := ParseProxyNode("http2://localhost:8000?blacklist=connect:google.pl:80,443")
+
+	assert.False(node.Can("connect", "google.pl:80"))
+	assert.False(node.Can("connect", "google.pl:443"))
+	assert.True(node.Can("connect", "google.pl:22"))
+	assert.True(node.Can("bind", "google.pl:80"))
+	assert.True(node.Can("bind", "google.com:80"))
+}

permissions.go

+package gost
+
+import (
+	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+
+	glob "github.com/ryanuber/go-glob"
+)
+
+type PortRange struct {
+	Min, Max int
+}
+
+type PortSet []PortRange
+
+type StringSet []string
+
+type Permission struct {
+	Actions StringSet
+	Hosts   StringSet
+	Ports   PortSet
+}
+
+type Permissions []Permission
+
+func minint(x, y int) int {
+	if x < y {
+		return x
+	}
+	return y
+}
+
+func maxint(x, y int) int {
+	if x > y {
+		return x
+	}
+	return y
+}
+
+func (ir *PortRange) Contains(value int) bool {
+	return value >= ir.Min && value <= ir.Max
+}
+
+func ParsePortRange(s string) (*PortRange, error) {
+	if s == "*" {
+		return &PortRange{Min: 0, Max: 65535}, nil
+	}
+
+	minmax := strings.Split(s, "-")
+	switch len(minmax) {
+	case 1:
+		port, err := strconv.Atoi(s)
+		if err != nil {
+			return nil, err
+		}
+		if port < 0 || port > 65535 {
+			return nil, fmt.Errorf("invalid port: %s", s)
+		}
+		return &PortRange{Min: port, Max: port}, nil
+	case 2:
+		min, err := strconv.Atoi(minmax[0])
+		if err != nil {
+			return nil, err
+		}
+		max, err := strconv.Atoi(minmax[1])
+		if err != nil {
+			return nil, err
+		}
+
+		realmin := maxint(0, minint(min, max))
+		realmax := minint(65535, maxint(min, max))
+
+		return &PortRange{Min: realmin, Max: realmax}, nil
+	default:
+		return nil, fmt.Errorf("invalid range: %s", s)
+	}
+}
+
+func (ps *PortSet) Contains(value int) bool {
+	for _, portRange := range *ps {
+		if portRange.Contains(value) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func ParsePortSet(s string) (*PortSet, error) {
+	ps := &PortSet{}
+
+	if s == "" {
+		return nil, errors.New("must specify at least one port")
+	}
+
+	ranges := strings.Split(s, ",")
+
+	for _, r := range ranges {
+		portRange, err := ParsePortRange(r)
+
+		if err != nil {
+			return nil, err
+		}
+
+		*ps = append(*ps, *portRange)
+	}
+
+	return ps, nil
+}
+
+func (ss *StringSet) Contains(subj string) bool {
+	for _, s := range *ss {
+		if glob.Glob(s, subj) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func ParseStringSet(s string) (*StringSet, error) {
+	ss := &StringSet{}
+	if s == "" {
+		return nil, errors.New("cannot be empty")
+	}
+
+	*ss = strings.Split(s, ",")
+
+	return ss, nil
+}
+
+func (ps *Permissions) Can(action string, host string, port int) bool {
+	for _, p := range *ps {
+		if p.Actions.Contains(action) && p.Hosts.Contains(host) && p.Ports.Contains(port) {
+			return true
+		}
+	}
+
+	return false
+}
+
+func ParsePermissions(s string) (*Permissions, error) {
+	ps := &Permissions{}
+
+	if s == "" {
+		return &Permissions{}, nil
+	}
+
+	perms := strings.Split(s, " ")
+
+	for _, perm := range perms {
+		parts := strings.Split(perm, ":")
+
+		switch len(parts) {
+		case 3:
+			actions, err := ParseStringSet(parts[0])
+
+			if err != nil {
+				return nil, fmt.Errorf("action list must look like connect,bind given: %s", parts[0])
+			}
+
+			hosts, err := ParseStringSet(parts[1])
+
+			if err != nil {
+				return nil, fmt.Errorf("hosts list must look like google.pl,*.google.com given: %s", parts[1])
+			}
+
+			ports, err := ParsePortSet(parts[2])
+
+			if err != nil {
+				return nil, fmt.Errorf("ports list must look like 80,8000-9000, given: %s", parts[2])
+			}
+
+			permission := Permission{Actions: *actions, Hosts: *hosts, Ports: *ports}
+
+			*ps = append(*ps, permission)
+		default:
+			return nil, fmt.Errorf("permission must have format [actions]:[hosts]:[ports] given: %s", perm)
+		}
+	}
+
+	return ps, nil
+}

permissions_test.go

+package gost
+
+import (
+	"fmt"
+	"testing"
+)
+
+var portRangeTests = []struct {
+	in  string
+	out *PortRange
+}{
+	{"1", &PortRange{Min: 1, Max: 1}},
+	{"1-3", &PortRange{Min: 1, Max: 3}},
+	{"3-1", &PortRange{Min: 1, Max: 3}},
+	{"0-100000", &PortRange{Min: 0, Max: 65535}},
+	{"*", &PortRange{Min: 0, Max: 65535}},
+}
+
+var stringSetTests = []struct {
+	in  string
+	out *StringSet
+}{
+	{"*", &StringSet{"*"}},
+	{"google.pl,google.com", &StringSet{"google.pl", "google.com"}},
+}
+
+var portSetTests = []struct {
+	in  string
+	out *PortSet
+}{
+	{"1,3", &PortSet{PortRange{Min: 1, Max: 1}, PortRange{Min: 3, Max: 3}}},
+	{"1-3,7-5", &PortSet{PortRange{Min: 1, Max: 3}, PortRange{Min: 5, Max: 7}}},
+	{"0-100000", &PortSet{PortRange{Min: 0, Max: 65535}}},
+	{"*", &PortSet{PortRange{Min: 0, Max: 65535}}},
+}
+
+var permissionsTests = []struct {
+	in  string
+	out *Permissions
+}{
+	{"", &Permissions{}},
+	{"*:*:*", &Permissions{
+		Permission{
+			Actions: StringSet{"*"},
+			Hosts:   StringSet{"*"},
+			Ports:   PortSet{PortRange{Min: 0, Max: 65535}},
+		},
+	}},
+	{"bind:127.0.0.1,localhost:80,443,8000-8100 connect:*.google.pl:80,443", &Permissions{
+		Permission{
+			Actions: StringSet{"bind"},
+			Hosts:   StringSet{"127.0.0.1", "localhost"},
+			Ports: PortSet{
+				PortRange{Min: 80, Max: 80},
+				PortRange{Min: 443, Max: 443},
+				PortRange{Min: 8000, Max: 8100},
+			},
+		},
+		Permission{
+			Actions: StringSet{"connect"},
+			Hosts:   StringSet{"*.google.pl"},
+			Ports: PortSet{
+				PortRange{Min: 80, Max: 80},
+				PortRange{Min: 443, Max: 443},
+			},
+		},
+	}},
+}
+
+func TestPortRangeParse(t *testing.T) {
+	for _, test := range portRangeTests {
+		actual, err := ParsePortRange(test.in)
+		if err != nil {
+			t.Errorf("ParsePortRange(%q) returned error: %v", test.in, err)
+		} else if *actual != *test.out {
+			t.Errorf("ParsePortRange(%q): got %v, want %v", test.in, actual, test.out)
+		}
+	}
+}
+
+func TestPortRangeContains(t *testing.T) {
+	actual, _ := ParsePortRange("5-10")
+
+	if !actual.Contains(5) || !actual.Contains(7) || !actual.Contains(10) {
+		t.Errorf("5-10 should contain 5, 7 and 10")
+	}
+
+	if actual.Contains(4) || actual.Contains(11) {
+		t.Errorf("5-10 should not contain 4, 11")
+	}
+}
+
+func TestStringSetParse(t *testing.T) {
+	for _, test := range stringSetTests {
+		actual, err := ParseStringSet(test.in)
+		if err != nil {
+			t.Errorf("ParseStringSet(%q) returned error: %v", test.in, err)
+		} else if fmt.Sprintln(actual) != fmt.Sprintln(test.out) {
+			t.Errorf("ParseStringSet(%q): got %v, want %v", test.in, actual, test.out)
+		}
+	}
+}
+
+func TestStringSetContains(t *testing.T) {
+	ss, _ := ParseStringSet("google.pl,*.google.com")
+
+	if !ss.Contains("google.pl") || !ss.Contains("www.google.com") {
+		t.Errorf("google.pl,*.google.com should contain google.pl and www.google.com")
+	}
+
+	if ss.Contains("www.google.pl") || ss.Contains("foobar.com") {
+		t.Errorf("google.pl,*.google.com shound not contain www.google.pl and foobar.com")
+	}
+}
+
+func TestPortSetParse(t *testing.T) {
+	for _, test := range portSetTests {
+		actual, err := ParsePortSet(test.in)
+		if err != nil {
+			t.Errorf("ParsePortRange(%q) returned error: %v", test.in, err)
+		} else if fmt.Sprintln(actual) != fmt.Sprintln(test.out) {
+			t.Errorf("ParsePortRange(%q): got %v, want %v", test.in, actual, test.out)
+		}
+	}
+}
+
+func TestPortSetContains(t *testing.T) {
+	actual, _ := ParsePortSet("5-10,20-30")
+
+	if !actual.Contains(5) || !actual.Contains(7) || !actual.Contains(10) {
+		t.Errorf("5-10,20-30 should contain 5, 7 and 10")
+	}
+
+	if !actual.Contains(20) || !actual.Contains(27) || !actual.Contains(30) {
+		t.Errorf("5-10,20-30 should contain 20, 27 and 30")
+	}
+
+	if actual.Contains(4) || actual.Contains(11) || actual.Contains(31) {
+		t.Errorf("5-10,20-30 should not contain 4, 11, 31")
+	}
+}
+
+func TestPermissionsParse(t *testing.T) {
+	for _, test := range permissionsTests {
+		actual, err := ParsePermissions(test.in)
+		if err != nil {
+			t.Errorf("ParsePermissions(%q) returned error: %v", test.in, err)
+		} else if fmt.Sprintln(actual) != fmt.Sprintln(test.out) {
+			t.Errorf("ParsePermissions(%q): got %v, want %v", test.in, actual, test.out)
+		}
+	}
+}

socks.go

@@ -3,13 +3,14 @@ package gost
 import (
 	"bytes"
 	"crypto/tls"
-	"github.com/ginuerzh/gosocks4"
-	"github.com/ginuerzh/gosocks5"
-	"github.com/golang/glog"
 	"net"
 	"net/url"
 	"strconv"
 	"time"
+
+	"github.com/ginuerzh/gosocks4"
+	"github.com/ginuerzh/gosocks5"
+	"github.com/golang/glog"
 )
 
 const (
@@ -191,7 +192,7 @@ func (s *Socks5Server) HandleRequest(req *gosocks5.Request) {
 		s.handleUDPRelay(req)
 
 	case CmdUdpTun:
-		glog.V(LINFO).Infof("[socks5-udp] %s - %s", s.conn.RemoteAddr(), req.Addr)
+		glog.V(LINFO).Infof("[socks5-rudp] %s - %s", s.conn.RemoteAddr(), req.Addr)
 		s.handleUDPTunnel(req)
 
 	default:
@@ -200,7 +201,16 @@ func (s *Socks5Server) HandleRequest(req *gosocks5.Request) {
 }
 
 func (s *Socks5Server) handleConnect(req *gosocks5.Request) {
-	cc, err := s.Base.Chain.Dial(req.Addr.String())
+	addr := req.Addr.String()
+
+	if !s.Base.Node.Can("tcp", addr) {
+		glog.Errorf("Unauthorized to tcp connect to %s", addr)
+		rep := gosocks5.NewReply(gosocks5.NotAllowed, nil)
+		rep.Write(s.conn)
+		return
+	}
+
+	cc, err := s.Base.Chain.Dial(addr)
 	if err != nil {
 		glog.V(LWARNING).Infof("[socks5-connect] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
 		rep := gosocks5.NewReply(gosocks5.HostUnreachable, nil)
@@ -226,7 +236,7 @@ func (s *Socks5Server) handleConnect(req *gosocks5.Request) {
 func (s *Socks5Server) handleBind(req *gosocks5.Request) {
 	cc, err := s.Base.Chain.GetConn()
 
-	// connection error
+	// connection error when forwarding bind
 	if err != nil && err != ErrEmptyChain {
 		glog.V(LWARNING).Infof("[socks5-bind] %s <- %s : %s", s.conn.RemoteAddr(), req.Addr, err)
 		reply := gosocks5.NewReply(gosocks5.Failure, nil)
@@ -234,23 +244,42 @@ func (s *Socks5Server) handleBind(req *gosocks5.Request) {
 		glog.V(LDEBUG).Infof("[socks5-bind] %s <- %s\n%s", s.conn.RemoteAddr(), req.Addr, reply)
 		return
 	}
+
 	// serve socks5 bind
 	if err == ErrEmptyChain {
-		s.bindOn(req.Addr.String())
+		addr := req.Addr.String()
+
+		if !s.Base.Node.Can("rtcp", addr) {
+			glog.Errorf("Unauthorized to tcp bind to %s", addr)
+			return
+		}
+
+		s.bindOn(addr)
+
 		return
 	}
 
-	defer cc.Close()
 	// forward request
+	// note: this type of request forwarding is defined when starting server
+	// so we don't need to authenticate it, as it's as explicit as whitelisting
+	defer cc.Close()
 	req.Write(cc)
-
 	glog.V(LINFO).Infof("[socks5-bind] %s <-> %s", s.conn.RemoteAddr(), cc.RemoteAddr())
 	s.Base.transport(s.conn, cc)
 	glog.V(LINFO).Infof("[socks5-bind] %s >-< %s", s.conn.RemoteAddr(), cc.RemoteAddr())
 }
 
 func (s *Socks5Server) handleUDPRelay(req *gosocks5.Request) {
-	bindAddr, _ := net.ResolveUDPAddr("udp", req.Addr.String())
+	addr := req.Addr.String()
+
+	if !s.Base.Node.Can("udp", addr) {
+		glog.Errorf("Unauthorized to udp connect to %s", addr)
+		rep := gosocks5.NewReply(gosocks5.NotAllowed, nil)
+		rep.Write(s.conn)
+		return
+	}
+
+	bindAddr, _ := net.ResolveUDPAddr("udp", addr)
 	relay, err := net.ListenUDP("udp", bindAddr) // udp associate, strict mode: if the port already in use, it will return error
 	if err != nil {
 		glog.V(LWARNING).Infof("[socks5-udp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
@@ -338,19 +367,26 @@ func (s *Socks5Server) handleUDPTunnel(req *gosocks5.Request) {
 
 	// connection error
 	if err != nil && err != ErrEmptyChain {
-		glog.V(LWARNING).Infof("[socks5-udp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
+		glog.V(LWARNING).Infof("[socks5-rudp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
 		reply := gosocks5.NewReply(gosocks5.Failure, nil)
 		reply.Write(s.conn)
-		glog.V(LDEBUG).Infof("[socks5-udp] %s -> %s\n%s", s.conn.RemoteAddr(), req.Addr, reply)
+		glog.V(LDEBUG).Infof("[socks5-rudp] %s -> %s\n%s", s.conn.RemoteAddr(), req.Addr, reply)
 		return
 	}
 
 	// serve tunnel udp, tunnel <-> remote, handle tunnel udp request
 	if err == ErrEmptyChain {
-		bindAddr, _ := net.ResolveUDPAddr("udp", req.Addr.String())
+		addr := req.Addr.String()
+
+		if !s.Base.Node.Can("rudp", addr) {
+			glog.Errorf("Unauthorized to udp bind to %s", addr)
+			return
+		}
+
+		bindAddr, _ := net.ResolveUDPAddr("udp", addr)
 		uc, err := net.ListenUDP("udp", bindAddr)
 		if err != nil {
-			glog.V(LWARNING).Infof("[socks5-udp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
+			glog.V(LWARNING).Infof("[socks5-rudp] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
 			return
 		}
 		defer uc.Close()
@@ -359,25 +395,27 @@ func (s *Socks5Server) handleUDPTunnel(req *gosocks5.Request) {
 		socksAddr.Host, _, _ = net.SplitHostPort(s.conn.LocalAddr().String())
 		reply := gosocks5.NewReply(gosocks5.Succeeded, socksAddr)
 		if err := reply.Write(s.conn); err != nil {
-			glog.V(LWARNING).Infof("[socks5-udp] %s <- %s : %s", s.conn.RemoteAddr(), socksAddr, err)
+			glog.V(LWARNING).Infof("[socks5-rudp] %s <- %s : %s", s.conn.RemoteAddr(), socksAddr, err)
 			return
 		}
-		glog.V(LDEBUG).Infof("[socks5-udp] %s <- %s\n%s", s.conn.RemoteAddr(), socksAddr, reply)
+		glog.V(LDEBUG).Infof("[socks5-rudp] %s <- %s\n%s", s.conn.RemoteAddr(), socksAddr, reply)
 
-		glog.V(LINFO).Infof("[socks5-udp] %s <-> %s", s.conn.RemoteAddr(), socksAddr)
+		glog.V(LINFO).Infof("[socks5-rudp] %s <-> %s", s.conn.RemoteAddr(), socksAddr)
 		s.tunnelServerUDP(s.conn, uc)
-		glog.V(LINFO).Infof("[socks5-udp] %s >-< %s", s.conn.RemoteAddr(), socksAddr)
+		glog.V(LINFO).Infof("[socks5-rudp] %s >-< %s", s.conn.RemoteAddr(), socksAddr)
 		return
 	}
 
 	defer cc.Close()
 
 	// tunnel <-> tunnel, direct forwarding
+	// note: this type of request forwarding is defined when starting server
+	// so we don't need to authenticate it, as it's as explicit as whitelisting
 	req.Write(cc)
 
-	glog.V(LINFO).Infof("[socks5-udp] %s <-> %s [tun]", s.conn.RemoteAddr(), cc.RemoteAddr())
+	glog.V(LINFO).Infof("[socks5-rudp] %s <-> %s [tun]", s.conn.RemoteAddr(), cc.RemoteAddr())
 	s.Base.transport(s.conn, cc)
-	glog.V(LINFO).Infof("[socks5-udp] %s >-< %s [tun]", s.conn.RemoteAddr(), cc.RemoteAddr())
+	glog.V(LINFO).Infof("[socks5-rudp] %s >-< %s [tun]", s.conn.RemoteAddr(), cc.RemoteAddr())
 }
 
 func (s *Socks5Server) bindOn(addr string) {
@@ -697,7 +735,16 @@ func (s *Socks4Server) HandleRequest(req *gosocks4.Request) {
 }
 
 func (s *Socks4Server) handleConnect(req *gosocks4.Request) {
-	cc, err := s.Base.Chain.Dial(req.Addr.String())
+	addr := req.Addr.String()
+
+	if !s.Base.Node.Can("tcp", addr) {
+		glog.Errorf("Unauthorized to tcp connect to %s", addr)
+		rep := gosocks5.NewReply(gosocks4.Rejected, nil)
+		rep.Write(s.conn)
+		return
+	}
+
+	cc, err := s.Base.Chain.Dial(addr)
 	if err != nil {
 		glog.V(LWARNING).Infof("[socks4-connect] %s -> %s : %s", s.conn.RemoteAddr(), req.Addr, err)
 		rep := gosocks4.NewReply(gosocks4.Failed, nil)

ssh.go

@@ -5,11 +5,12 @@ package gost
 import (
 	"encoding/binary"
 	"fmt"
-	"github.com/golang/glog"
-	"golang.org/x/crypto/ssh"
 	"net"
 	"net/url"
 	"strconv"
+
+	"github.com/golang/glog"
+	"golang.org/x/crypto/ssh"
 )
 
 // Applicaple SSH Request types for Port Forwarding - RFC 4254 7.X
@@ -121,6 +122,11 @@ func (s *SSHServer) directPortForwardChannel(channel ssh.Channel, raddr string)
 
 	glog.V(LINFO).Infof("[ssh-tcp] %s - %s", s.Addr, raddr)
 
+	if !s.Base.Node.Can("tcp", raddr) {
+		glog.Errorf("Unauthorized to tcp connect to %s", raddr)
+		return
+	}
+
 	conn, err := s.Base.Chain.Dial(raddr)
 	if err != nil {
 		glog.V(LINFO).Infof("[ssh-tcp] %s - %s : %s", s.Addr, raddr, err)
@@ -143,6 +149,13 @@ func (s *SSHServer) tcpipForwardRequest(sshConn ssh.Conn, req *ssh.Request, quit
 	t := tcpipForward{}
 	ssh.Unmarshal(req.Payload, &t)
 	addr := fmt.Sprintf("%s:%d", t.Host, t.Port)
+
+	if !s.Base.Node.Can("rtcp", addr) {
+		glog.Errorf("Unauthorized to tcp bind to %s", addr)
+		req.Reply(false, nil)
+		return
+	}
+
 	glog.V(LINFO).Infoln("[ssh-rtcp] listening tcp", addr)
 	ln, err := net.Listen("tcp", addr) //tie to the client connection
 	if err != nil {