internal: parse extrainfo with '\,' and '\=' (5aff30df) · Commits · The Tor Project / Anti-censorship / rdsys

internal/kraken.go

+42 −7

Original line number	Diff line number	Diff line
		@@ -13,6 +13,7 @@ import (
		"net"
		"os"
		"reflect"
		"regexp"
		"strconv"
		"strings"
		"time"
		@@ -33,6 +34,11 @@ const (
		RecordEndPrefix = "-----END SIGNATURE-----"
		)

		var (
		uncommentedComma = regexp.MustCompile("[^\\\\],")
		uncommentedEqual = regexp.MustCompile("[^\\\\]=")
		)

		type flicker struct {
		speed int
		flickered bool
		@@ -441,7 +447,8 @@ func parseExtrainfoDoc(r io.Reader) (map[string]*resources.Bridge, error) {
		t.Fingerprint = b.Fingerprint
		err := populateTransportInfo(line, t)
		if err != nil {
		return nil, err
		log.Println(err)
		continue
		}
		b.AddTransport(t)
		}
		@@ -503,13 +510,41 @@ func populateTransportInfo(transport string, t *resources.Transport) error {

		// We may be dealing with one or more key=value pairs.
		if len(words) > MinTransportWords {
		args := strings.Split(words[3], ",")
		for _, arg := range args {
		kv := strings.Split(arg, "=")
		if len(kv) != 2 {
		return fmt.Errorf("key:value pair in %q not separated by a '='", words[3])
		args := words[3]

		parseArg := func(start, end int) error {
		arg := args[start:end]
		arg = strings.ReplaceAll(arg, "\\,", ",")

		argIndexes := uncommentedEqual.FindAllStringIndex(arg, -1)
		if len(argIndexes) != 1 {
		return fmt.Errorf("transport arg has an unsupported format: %s", arg)
		}

		key := arg[0 : argIndexes[0][1]-1]
		key = strings.ReplaceAll(key, "\\=", "=")
		value := arg[argIndexes[0][1]:]
		value = strings.ReplaceAll(value, "\\=", "=")

		t.Parameters[key] = value
		return nil
		}
		t.Parameters[kv[0]] = kv[1]

		start := 0
		for _, index := range uncommentedComma.FindAllStringIndex(args, -1) {
		if len(index) != 2 {
		return fmt.Errorf("transport args has an unsupported format: %s", args)
		}
		err := parseArg(start, index[1]-1)
		if err != nil {
		return err
		}

		start = index[1]
		}
		err := parseArg(start, len(args))
		if err != nil {
		return err
		}
		}

internal/kraken_test.go

+80 −0

Original line number	Diff line number	Diff line
		@@ -5,6 +5,7 @@
		package internal

		import (
		"reflect"
		"slices"
		"testing"

		@@ -269,3 +270,82 @@ func TestBridgeWithPTnotAsVanilla(t *testing.T) {
		}
		}
		}

		func TestTransportInfo(t *testing.T) {
		type transportInfo struct {
		Type string
		IPVer core.IPVersion
		Address string
		Port uint16
		Parameters map[string]string
		}
		transportLines := map[string]transportInfo{
		"transport obfs4 139.55.50.64:39071 cert=ZZZZZZZZZZZ,iat-mode=0": transportInfo{
		Type: "obfs4",
		IPVer: core.IPv4,
		Address: "139.55.50.64",
		Port: 39071,
		Parameters: map[string]string{"cert": "ZZZZZZZZZZZ", "iat-mode": "0"},
		},
		"transport obfs4 [2a0c:4d80:42:702::1]:27015 cert=TD7PbUO0/0k6xYHMPW3vJxICfkMZNdkRrb63Zhl5j9dW3iRGiCx0A7mPhe5T2EDzQ35+Zw,iat-mode=0": transportInfo{
		Type: "obfs4",
		IPVer: core.IPv6,
		Address: "2a0c:4d80:42:702::1",
		Port: 27015,
		Parameters: map[string]string{"cert": "TD7PbUO0/0k6xYHMPW3vJxICfkMZNdkRrb63Zhl5j9dW3iRGiCx0A7mPhe5T2EDzQ35+Zw", "iat-mode": "0"},
		},
		"transport webtunnel [2001:db8:d21c::2bc4]:443 url=https://example.com/something-random": transportInfo{
		Type: "webtunnel",
		IPVer: core.IPAny,
		Address: "2001:db8:d21c::2bc4",
		Port: 443,
		Parameters: map[string]string{"url": "https://example.com/something-random"},
		},
		"transport obfs4 139.55.50.64:39071 cert=Z\\=Z\\=Z,iat-mode=0": transportInfo{
		Type: "obfs4",
		IPVer: core.IPv4,
		Address: "139.55.50.64",
		Port: 39071,
		Parameters: map[string]string{"cert": "Z=Z=Z", "iat-mode": "0"},
		},
		"transport obfs4 139.55.50.64:39071 cert=Z\\,Z\\,Z,iat-mode=0": transportInfo{
		Type: "obfs4",
		IPVer: core.IPv4,
		Address: "139.55.50.64",
		Port: 39071,
		Parameters: map[string]string{"cert": "Z,Z,Z", "iat-mode": "0"},
		},
		"transport obfs4 139.55.50.64:39071 cert=Z\\,\\=Z\\=Z\\,,ia\\,t-m\\=ode\\==0": transportInfo{
		Type: "obfs4",
		IPVer: core.IPv4,
		Address: "139.55.50.64",
		Port: 39071,
		Parameters: map[string]string{"cert": "Z,=Z=Z,", "ia,t-m=ode=": "0"},
		},
		}

		for line, transport := range transportLines {
		parsedTransport := resources.NewTransport()
		err := populateTransportInfo(line, parsedTransport)
		if err != nil {
		t.Error("Error propulating transport info for ", line, err)
		continue
		}

		if !reflect.DeepEqual(parsedTransport.Parameters, transport.Parameters) {
		t.Error(line, "didn't produce the right parameters:", parsedTransport.Parameters)
		}
		if parsedTransport.Type() != transport.Type {
		t.Error(line, "didn't produce the right type:", parsedTransport.Type())
		}
		if parsedTransport.IPVer != transport.IPVer {
		t.Error(line, "didn't produce the right IPVer:", parsedTransport.IPVer)
		}
		if parsedTransport.Address.String() != transport.Address {
		t.Error(line, "didn't produce the right address:", parsedTransport.Address.String())
		}
		if parsedTransport.Port != transport.Port {
		t.Error(line, "didn't produce the right port:", parsedTransport.Port)
		}
		}
		}