fixed trigger out of bounds panic, test all strategies w/ pcap file (…

…file not included) (#7) * fixed trigger out of bounds panic, test all strategies w/ pcap file
getlantern · Mar 2, 2024 · 4935a8c · 4935a8c
1 parent 9997753
commit 4935a8c
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Showing 8 changed files with 144 additions and 140 deletions.
diff --git a/.gitignore b/.gitignore
@@ -1,3 +1,4 @@
 /geneva
 /geneva.exe
 profile.cov
+/internal/testdata/input.pcap
diff --git a/actions/tamper_action.go b/actions/tamper_action.go
@@ -236,7 +236,7 @@ var (
 		"dataofs":           TCPFieldDataOff,
 		"flags":             TCPFieldFlags,
 		"window":            TCPFieldWindow,
-		"urgent":            TCPFieldUrgent,
+		"urgptr":            TCPFieldUrgent,
 		"chksum":            TCPFieldChecksum,
 		"options-eol":       TCPOptionEol,
 		"options-nop":       TCPOptionNop,
@@ -253,8 +253,8 @@ var (
 
 	// tcpOptionLengths is a map of TCP options to the length of their data field.
 	tcpOptionLengths = map[TCPField]int{
-		TCPOptionEol:       0,
-		TCPOptionNop:       0,
+		TCPOptionEol:       1,
+		TCPOptionNop:       1,
 		TCPOptionMss:       2,
 		TCPOptionWscale:    1,
 		TCPOptionSackok:    0, // the geneva team has this listed as 0, so at most the data is deleted
@@ -313,14 +313,20 @@ func NewTCPTamperAction(ta TamperAction) (*TCPTamperAction, error) {
 		case field == TCPLoad:
 			gen.vBytes = []byte(ta.NewValue)
 		default:
-			val, err := strconv.ParseUint(ta.NewValue, 10, 32)
-			if err != nil {
-				return nil, fmt.Errorf(
-					"%w: %q is not a valid value for field %q",
-					ErrInvalidTamperRule,
-					ta.NewValue,
-					ta.Field,
-				)
+			var (
+				val uint64
+				err error
+			)
+			if ta.NewValue != "" {
+				val, err = strconv.ParseUint(ta.NewValue, 10, 32)
+				if err != nil {
+					return nil, fmt.Errorf(
+						"%w: %q is not a valid value for field %q",
+						ErrInvalidTamperRule,
+						ta.NewValue,
+						ta.Field,
+					)
+				}
 			}
 
 			gen.vUint = uint32(val)

diff --git a/geneva_test.go b/geneva_test.go
@@ -3,43 +3,57 @@ package geneva_test
 import (
 	"testing"
 
+	"github.com/google/gopacket"
+	"github.com/google/gopacket/layers"
+	"github.com/google/gopacket/pcap"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+
 	"github.com/getlantern/geneva"
+	"github.com/getlantern/geneva/strategy"
 )
 
-var examples = []string{
-	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{TCP:chksum:corrupt},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{IP:ttl:replace:10},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{TCP:ack:corrupt},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:options-wscale:corrupt}(tamper{TCP:dataofs:replace:8},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{TCP:chksum:corrupt},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{IP:ttl:replace:8},),)-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{TCP:ack:corrupt},),)-|",
-	"[TCP:flags:S]-duplicate(,tamper{TCP:load:corrupt})-|",
-	"[TCP:flags:PA]-duplicate(tamper{IP:len:replace:64},)-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:R}(tamper{TCP:chksum:corrupt},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:R}(tamper{IP:ttl:replace:10},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:options-md5header:corrupt}(tamper{TCP:flags:replace:R},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:RA}(tamper{TCP:chksum:corrupt},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:RA}(tamper{IP:ttl:replace:10},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:options-md5header:corrupt}(tamper{TCP:flags:replace:R},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FRAPUEN}(tamper{TCP:chksum:corrupt},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FREACN}(tamper{IP:ttl:replace:10},))-|",
-	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FRAPUN}(tamper{TCP:options-md5header:corrupt},))-|",
-	"[TCP:flags:PA]-fragment{tcp:8:False}-| [TCP:flags:A]-tamper{TCP:seq:corrupt}-|",
-	"[TCP:flags:PA]-fragment{tcp:8:True}(,fragment{tcp:4:True})-|",
-	"[TCP:flags:PA]-fragment{tcp:-1:True}-|",
-	"[TCP:flags:PA]-duplicate(tamper{TCP:flags:replace:F}(tamper{IP:len:replace:78},),)-|",
-	"[TCP:flags:S]-duplicate(tamper{TCP:flags:replace:SA},)-|",
-	"[TCP:flags:PA]-tamper{TCP:options-uto:corrupt}-|",
-}
-
 func TestNewStrategy(t *testing.T) {
 	t.Parallel()
 
-	for i, s := range examples {
+	for i, s := range geneva.Strategies {
 		_, err := geneva.NewStrategy(s)
-		if err != nil {
-			t.Errorf("failed to parse strategy %d %q: %v", i, s, err)
+		assert.NoError(t, err, "failed to parse strategy %d %q", i, s)
+	}
+}
+
+func TestApplyAllStrategies(t *testing.T) {
+	t.Skip("no input pcap file")
+
+	t.Parallel()
+
+	t.Log("reading pcap file")
+
+	packets := []gopacket.Packet{}
+	handle, err := pcap.OpenOffline("internal/testdata/input.pcap")
+	require.NoError(t, err, "failed to open pcap file")
+
+	packetSource := gopacket.NewPacketSource(handle, handle.LinkType())
+	for packet := range packetSource.Packets() {
+		packets = append(packets, packet)
+	}
+
+	t.Log("parsing strategies")
+
+	strategies := []*strategy.Strategy{}
+	for _, s := range geneva.Strategies {
+		strat, err := geneva.NewStrategy(s)
+		assert.NoError(t, err, "failed to parse strategy %q", s)
+		strategies = append(strategies, strat)
+	}
+
+	t.Log("applying strategies")
+
+	for _, s := range strategies {
+		for _, p := range packets {
+			p := gopacket.NewPacket(p.Data(), layers.LayerTypeEthernet, gopacket.Default)
+			_, err := s.Apply(p, strategy.DirectionOutbound)
+			assert.NoError(t, err, "strategy: %s\n%v", s, p)
 		}
 	}
 }
diff --git a/strategies.go b/strategies.go
@@ -0,0 +1,67 @@
+package geneva
+
+var Strategies = []string{
+	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{TCP:chksum:corrupt},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{IP:ttl:replace:10},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:dataofs:replace:10}(tamper{TCP:ack:corrupt},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:options-wscale:corrupt}(tamper{TCP:dataofs:replace:8},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{TCP:chksum:corrupt},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{IP:ttl:replace:8},),)-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:load:corrupt}(tamper{TCP:ack:corrupt},),)-| \\/",
+	"[TCP:flags:S]-duplicate(,tamper{TCP:load:corrupt})-| \\/",
+	"[TCP:flags:PA]-duplicate(tamper{IP:len:replace:64},)-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:R}(tamper{TCP:chksum:corrupt},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:R}(tamper{IP:ttl:replace:10},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:options-md5header:corrupt}(tamper{TCP:flags:replace:R},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:RA}(tamper{TCP:chksum:corrupt},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:RA}(tamper{IP:ttl:replace:10},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:options-md5header:corrupt}(tamper{TCP:flags:replace:R},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FRAPUEN}(tamper{TCP:chksum:corrupt},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FREACN}(tamper{IP:ttl:replace:10},))-| \\/",
+	"[TCP:flags:A]-duplicate(,tamper{TCP:flags:replace:FRAPUN}(tamper{TCP:options-md5header:corrupt},))-| \\/",
+	"[TCP:flags:PA]-fragment{tcp:8:False}-| [TCP:flags:A]-tamper{TCP:seq:corrupt}-| \\/",
+	"[TCP:flags:PA]-fragment{tcp:8:True}(,fragment{tcp:4:True})-| \\/",
+	"[TCP:flags:PA]-fragment{tcp:-1:True}-|  \\/",
+	"[TCP:flags:PA]-duplicate(tamper{TCP:flags:replace:F}(tamper{IP:len:replace:78},),)-|  \\/",
+	"[TCP:flags:S]-duplicate(tamper{TCP:flags:replace:SA},)-| \\/",
+	"[TCP:flags:PA]-tamper{TCP:options-uto:corrupt}-|  \\/",
+
+	"[TCP:options-sackok:]-tamper{TCP:dataofs:replace:7}-| \\/",
+	"[TCP:options-sack::4]-fragment{tcp:-1:False}-| \\/",
+	"[TCP:options-nop:]-tamper{TCP:urgptr:corrupt}(tamper{TCP:options-eol:corrupt},)-| \\/",
+	"[TCP:options-nop:]-fragment{ip:-1:True:9}(drop,)-| \\/",
+	"[TCP:urgptr:0]-duplicate-| \\/",
+	"[TCP:dataofs:10:3]-tamper{TCP:options-mss:replace:17484}(fragment{tcp:-1:False},)-| \\/",
+	"[TCP:options-sack:]-tamper{TCP:window:corrupt}(tamper{TCP:options-eol:corrupt},)-| \\/",
+	"[TCP:options-altchksum:]-duplicate(fragment{ip:-1:False},)-| \\/",
+	"[TCP:options-altchksumopt:]-fragment{tcp:-1:True}-| \\/",
+	"[TCP:dataofs:8]-duplicate(duplicate,)-| \\/",
+	"[TCP:options-md5header:]-duplicate-| \\/",
+	"[TCP:options-md5header:]-fragment{tcp:-1:False}-| [TCP:options-wscale:7]-drop-| \\/",
+	"[TCP:options-uto:]-duplicate(,tamper{TCP:load:replace:y0qgai1woz})-| \\/",
+	"[TCP:options-sackok::1]-tamper{TCP:window:replace:120}(tamper{TCP:ack:corrupt},)-| \\/",
+	"[TCP:load:]-tamper{TCP:options-uto:corrupt}(fragment{tcp:-1:False},)-| [TCP:options-uto:]-tamper{TCP:options-mss:replace:}-| \\/",
+	"[TCP:options-wscale:]-tamper{TCP:options-nop:corrupt}(tamper{TCP:options-altchksum:replace:},)-| \\/",
+	"[TCP:options-sack::1]-tamper{TCP:chksum:replace:22170}-| \\/",
+	"[TCP:load:]-fragment{tcp:-1:False}(tamper{TCP:urgptr:replace:29},)-| \\/",
+	"[TCP:urgptr:0]-fragment{tcp:-1:False}(duplicate,tamper{TCP:options-sackok:replace:})-| \\/",
+	"[TCP:options-eol:]-tamper{TCP:window:corrupt}-| \\/",
+	"[TCP:options-uto:]-tamper{TCP:options-altchksum:replace:90}(duplicate(tamper{TCP:options-sack:replace:},),)-| \\/",
+	"[TCP:options-altchksumopt:]-tamper{TCP:options-uto:replace:}(tamper{TCP:load:corrupt}(fragment{tcp:-1:True}(,drop),),)-| \\/",
+	"[TCP:options-altchksumopt:]-fragment{tcp:-1:False}(drop,duplicate)-| \\/",
+	"[TCP:options-eol:]-tamper{TCP:urgptr:corrupt}(duplicate,)-| \\/",
+	"[TCP:options-sack:]-duplicate(tamper{TCP:urgptr:corrupt}(fragment{tcp:-1:False},),)-| \\/",
+	"[TCP:options-nop::2]-fragment{tcp:46:True}(fragment{tcp:-1:True},)-| \\/",
+	"[TCP:chksum:26741]-duplicate(tamper{TCP:options-timestamp:replace:},)-| \\/",
+	"[TCP:options-uto:]-duplicate(,tamper{TCP:options-nop:replace:})-| \\/",
+	"[TCP:options-altchksum:]-tamper{TCP:options-wscale:replace:248}(tamper{TCP:options-sackok:replace:},)-| \\/",
+	"[TCP:options-sackok:]-duplicate(duplicate(,tamper{TCP:load:replace:GET%20/%3Fq%3Dultrasurf%20HTTP/1.1%0D%0AHost%3A%2023.88.46.143%3A4228%0D%0AUser-Agent%3A%20python-requests/2.23.0%0D%0AAccept-Encoding%3A%20gzip%2C%20deflate%0D%0AAccept%3A%20%2A/%2A%0D%0AConnection%3A%20keep-alive%0D%0A%0D%0A}),duplicate)-| \\/",
+	"[TCP:options-sackok::1]-fragment{tcp:29:False:14}(tamper{TCP:options-timestamp:replace:4263716593},)-| \\/",
+	"[TCP:options-altchksumopt:]-tamper{TCP:options-nop:corrupt}(duplicate,)-| \\/",
+
+	// Can't find where these Strategies came from. They are not in the geneva paper or the geneva team's repo.
+	// "[TCP:reserved:0]-fragment{tcp:-1:True}(,tamper{TCP:options-uto:replace:})-| \\/",
+	// "[TCP:options-nop:]-tamper{TCP:load:replace:}(tamper{TCP:reserved:corrupt}(tamper{TCP:options-sackok:corrupt},),)-| \\/",
+	// "[TCP:options-sack:]-fragment{tcp:-1:True}(,tamper{TCP:reserved:replace:1})-| \\/",
+	// "[TCP:reserved:0]-duplicate(tamper{TCP:options-sackok:corrupt},)-| \\/",
+}
diff --git a/strategies.txt b/strategies.txt
diff --git a/triggers/ip_trigger.go b/triggers/ip_trigger.go
@@ -1,6 +1,7 @@
 package triggers
 
 import (
+	"bytes"
 	"fmt"
 	"net"
 	"strconv"
@@ -110,17 +111,7 @@ func (t *IPTrigger) Matches(pkt gopacket.Packet) (bool, error) {
 	case IPFieldDestAddress:
 		return ipLayer.DstIP.Equal(net.ParseIP(t.value)), nil
 	case IPFieldPayload:
-		if len(ipLayer.Payload) < len(t.value) {
-			return false, nil
-		}
-
-		for i, r := range []byte(t.value) {
-			if r != ipLayer.Payload[i] {
-				return false, nil
-			}
-		}
-
-		return true, nil
+		return bytes.Equal(ipLayer.Payload, []byte(t.value)), nil
 	}
 
 	// The rest of the triggers work on numbers.

diff --git a/triggers/tcp_trigger.go b/triggers/tcp_trigger.go
@@ -1,6 +1,7 @@
 package triggers
 
 import (
+	"bytes"
 	"errors"
 	"fmt"
 	"math"
@@ -182,17 +183,7 @@ func matchTCPOption(field TCPField, value string, tcpLayer *layers.TCP) (bool, e
 
 	for _, opt := range tcpLayer.Options {
 		if opt.OptionType == optKind {
-			if len(opt.OptionData) < len(value) {
-				return false, nil
-			}
-
-			for i, b := range opt.OptionData {
-				if b != []byte(value)[i] {
-					return false, nil
-				}
-			}
-
-			return true, nil
+			return bytes.Equal(opt.OptionData, []byte(value)), nil
 		}
 	}
 
@@ -210,18 +201,7 @@ func (t *TCPTrigger) Matches(pkt gopacket.Packet) (bool, error) {
 	case TCPFieldFlags:
 		return matchField(t.value, tcpLayer), nil
 	case TCPFieldPayload:
-		if len(tcpLayer.Payload) < len(t.value) {
-			return false, nil
-		}
-
-		for i, r := range []byte(t.value) {
-			if r != tcpLayer.Payload[i] {
-				return false, nil
-			}
-		}
-
-		return true, nil
-
+		return bytes.Equal(tcpLayer.Payload, []byte(t.value)), nil
 	case TCPFieldOptionEOL, TCPFieldOptionNOP, TCPFieldOptionMSS, TCPFieldOptionWScale,
 		TCPFieldOptionSackOk, TCPFieldOptionSack, TCPFieldOptionTimestamp,
 		TCPFieldOptionAltChecksum, TCPFieldOptionAltChecksumOpt, TCPFieldOptionMD5Header,

diff --git a/triggers/trigger_test.go b/triggers/trigger_test.go
@@ -5,10 +5,11 @@ import (
 	"reflect"
 	"testing"
 
-	"github.com/getlantern/geneva/internal/scanner"
-	"github.com/getlantern/geneva/triggers"
 	"github.com/google/gopacket"
 	"github.com/google/gopacket/layers"
+
+	"github.com/getlantern/geneva/internal/scanner"
+	"github.com/getlantern/geneva/triggers"
 )
 
 func TestParseTrigger(t *testing.T) {
@@ -215,8 +216,13 @@ func TestIPTriggers(t *testing.T) {
 		{"src-invalid", "src", "192.168.1.48", false},
 		{"dst-valid", "dst", "192.168.2.1", true},
 		{"dst-invalid", "dst", "192.168.1.3", false},
-		{"load-valid", "load", "\xee\x3a\x00", true},
-		{"load-invalid", "load", "\xee\x3a\x00\f7", false},
+		{
+			"load-valid",
+			"load",
+			"\xee\x3a\x00\x16\x6b\x8b\xad\x49\x9f\x7b\x50\xae\x80\x18\x08\x0a\x61\x41\x00\x00\x01\x01\x08\x0a\x8b\xc1\xd9\x53\x28\xbf\x41\x06\x53\x53\x48\x2d\x32\x2e\x30\x2d\x4f\x70\x65\x6e\x53\x53\x48\x5f\x38\x2e\x31\x0d\x0a",
+			true,
+		},
+		{"load-invalid", "load", "\xee\x3a\x00\xf7", false},
 	}
 
 	for _, tc := range tt {