Merge pull request #638 from adotkhan/bytes

Byte generation with goregen

.github/workflows/tests.yml

@@ -80,6 +80,7 @@ jobs:
           go test -v -race ./psiphon/common/accesscontrol
           go test -v -race ./psiphon/common/crypto/ssh
           go test -v -race ./psiphon/common/fragmentor
+          go test -v -race ./psiphon/common/regen
           go test -v -race ./psiphon/common/monotime
           go test -v -race ./psiphon/common/obfuscator
           go test -v -race ./psiphon/common/osl
@@ -111,6 +112,7 @@ jobs:
           go test -v -covermode=count -coverprofile=accesscontrol.coverprofile ./psiphon/common/accesscontrol
           go test -v -covermode=count -coverprofile=ssh.coverprofile ./psiphon/common/crypto/ssh
           go test -v -covermode=count -coverprofile=fragmentor.coverprofile ./psiphon/common/fragmentor
+          go test -v -covermode=count -coverprofile=regen.coverprofile ./psiphon/common/regen
           go test -v -covermode=count -coverprofile=monotime.coverprofile ./psiphon/common/monotime
           go test -v -covermode=count -coverprofile=obfuscator.coverprofile ./psiphon/common/obfuscator
           go test -v -covermode=count -coverprofile=osl.coverprofile ./psiphon/common/osl

go.mod

@@ -47,7 +47,6 @@ require (
 	github.com/stretchr/testify v1.7.1
 	github.com/syndtr/gocapability v0.0.0-20170704070218-db04d3cc01c8
 	github.com/wader/filtertransport v0.0.0-20200316221534-bdd9e61eee78
-	github.com/zach-klippenstein/goregen v0.0.0-20160303162051-795b5e3961ea
 	golang.org/x/crypto v0.0.0-20221012134737-56aed061732a
 	golang.org/x/net v0.7.0
 	golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4
@@ -70,7 +69,6 @@ require (
 	github.com/golang/mock v1.6.0 // indirect
 	github.com/golang/protobuf v1.5.3-0.20210916003710-5d5e8c018a13 // indirect
 	github.com/google/go-cmp v0.5.8 // indirect
-	github.com/google/gxui v0.0.0-20151028112939-f85e0a97b3a4 // indirect
 	github.com/google/pprof v0.0.0-20210407192527-94a9f03dee38 // indirect
 	github.com/josharian/native v1.0.0 // indirect
 	github.com/kardianos/osext v0.0.0-20170510131534-ae77be60afb1 // indirect
@@ -83,7 +81,6 @@ require (
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/quic-go/qpack v0.4.0 // indirect
 	github.com/sergeyfrolov/bsbuffer v0.0.0-20180903213811-94e85abb8507 // indirect
-	github.com/smartystreets/goconvey v1.7.2 // indirect
 	gitlab.com/yawning/obfs4.git v0.0.0-20190120164510-816cff15f425 // indirect
 	golang.org/x/exp v0.0.0-20221012211006-4de253d81b95 // indirect
 	golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4 // indirect

psiphon/common/parameters/frontingSpec.go

@@ -24,7 +24,7 @@ import (
 
 	"github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common/errors"
 	"github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common/prng"
-	regen "github.com/zach-klippenstein/goregen"
+	"github.com/Psiphon-Labs/psiphon-tunnel-core/psiphon/common/regen"
 )
 
 // FrontingSpecs is a list of domain fronting specs.
@@ -73,7 +73,7 @@ func (specs FrontingSpecs) SelectParameters() (
 		return "", "", "", "", nil, "", errors.TraceNew("missing fronting address")
 	}
 
-	frontingDialAddr, err := regen.Generate(
+	frontingDialAddr, err := regen.GenerateString(
 		spec.Addresses[prng.Intn(len(spec.Addresses))])
 	if err != nil {
 		return "", "", "", "", nil, "", errors.Trace(err)

vendor/github.com/zach-klippenstein/goregen/char_class.go → psiphon/common/regen/char_class.go

@@ -14,10 +14,30 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+/*
+ * Copyright (c) 2023, Psiphon Inc.
+ * All rights reserved.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
 package regen
 
 import (
 	"fmt"
+	"math"
 )
 
 // CharClass represents a regular expression character class as a list of ranges.
@@ -57,7 +77,7 @@ e.g.
 func parseCharClass(runes []rune) *tCharClass {
 	var totalSize int32
 	numRanges := len(runes) / 2
-	ranges := make([]tCharClassRange, numRanges, numRanges)
+	ranges := make([]tCharClassRange, numRanges)
 
 	for i := 0; i < numRanges; i++ {
 		start := runes[i*2]
@@ -79,6 +99,38 @@ func parseCharClass(runes []rune) *tCharClass {
 	return &tCharClass{ranges, totalSize}
 }
 
+// parseByteClass parses character classes only for byte values (0-255).
+// Returns nil if runes does not contain any byte values.
+//
+// Note:
+// If an end range is greater than 255, it is truncated to 255.
+func parseByteClass(runes []rune) *tCharClass {
+	var totalSize int32
+
+	var ranges []tCharClassRange
+	for i := 0; i < len(runes)-1; i += 2 {
+		start := runes[i]
+		end := runes[i+1]
+
+		var r tCharClassRange
+
+		if start <= math.MaxUint8 {
+			if end > math.MaxUint8 {
+				end = math.MaxUint8
+			}
+			r = newCharClassRange(start, end)
+			ranges = append(ranges, r)
+			totalSize += r.Size
+		}
+	}
+
+	if len(ranges) == 0 {
+		return nil
+	}
+
+	return &tCharClass{ranges, totalSize}
+}
+
 // GetRuneAt gets a rune from CharClass as a contiguous array of runes.
 func (class *tCharClass) GetRuneAt(i int32) rune {
 	for _, r := range class.Ranges {
@@ -95,10 +147,6 @@ func (class *tCharClass) String() string {
 }
 
 func newCharClassRange(start rune, end rune) tCharClassRange {
-	if start < 1 {
-		panic("char class range cannot contain runes less than 1")
-	}
-
 	size := end - start + 1
 
 	if size < 1 {
@@ -113,8 +161,8 @@ func newCharClassRange(start rune, end rune) tCharClassRange {
 
 func (r tCharClassRange) String() string {
 	if r.Size == 1 {
-		return fmt.Sprintf("%s:1", runesToString(r.Start))
+		return fmt.Sprintf("%s:1", runesToUTF8(r.Start))
 	}
-	return fmt.Sprintf("%s-%s:%d", runesToString(r.Start), runesToString(r.Start+rune(r.Size-1)), r.Size)
+	return fmt.Sprintf("%s-%s:%d", runesToUTF8(r.Start), runesToUTF8(r.Start+rune(r.Size-1)), r.Size)
 
 }

psiphon/common/regen/generator_error_test.go

@@ -0,0 +1,45 @@
+/*
+Copyright 2014 Zachary Klippenstein
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package regen
+
+import (
+	"errors"
+	"testing"
+)
+
+func TestGeneratorError(t *testing.T) {
+
+	t.Run("Handles nil cause", func(t *testing.T) {
+		err := generatorError(nil, "msg")
+		if err == nil {
+			t.Fatal("Expected error, got nil")
+		}
+		if err.Error() != "msg" {
+			t.Fatalf("Expected error message 'msg', got '%s'", err.Error())
+		}
+	})
+
+	t.Run("Formats", func(t *testing.T) {
+		err := generatorError(errors.New("cause"), "msg %s", "arg")
+		if err == nil {
+			t.Fatal("Expected error, got nil")
+		}
+		if err.Error() != "msg arg\ncaused by cause" {
+			t.Fatalf("Expected error message 'msg arg\ncaused by cause', got '%s'", err.Error())
+		}
+	})
+}