调整 padding 包

Author: FishGoddess

.github/workflows/test.yml

@@ -7,10 +7,20 @@ on:
 
 jobs:
   test-project:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
+      - run: uname -a
+      - run: lsb_release -a
+
+      - name: Setup
+        uses: actions/setup-go@v4
+        with:
+          go-version: "1.25"
+
+      - run: go version
+
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
 
       - name: Test
-        run: make test
+        run: make test

go.mod

@@ -1,3 +1,3 @@
 module github.com/FishGoddess/cryptox
 
-go 1.21
+go 1.25

internal/padding/none.go

@@ -0,0 +1,15 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+type paddingNone struct{}
+
+func (paddingNone) Pad(bs []byte, blockSize int) []byte {
+	return bs
+}
+
+func (paddingNone) Unpad(bs []byte, blockSize int) ([]byte, error) {
+	return bs, nil
+}

internal/padding/none_test.go

@@ -0,0 +1,19 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import "testing"
+
+// go test -v -cover -run=^TestNone$
+func TestNone(t *testing.T) {
+	testCases := []testCase{
+		{Data: []byte{}, PaddingData: []byte{}},
+		{Data: []byte{1, 2, 3, 4, 5}, PaddingData: []byte{1, 2, 3, 4, 5}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 0}},
+	}
+
+	testPadding(t, None, testCases)
+}

internal/padding/padding.go

@@ -0,0 +1,21 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+var (
+	None  Padding = paddingNone{}
+	Zero  Padding = paddingZero{}
+	PKCS5 Padding = paddingPKCS5{}
+	PKCS7 Padding = paddingPKCS7{}
+)
+
+// Padding will pad a byte slice with some []byte and unpad them with the same []byte.
+type Padding interface {
+	// Pad pads some []byte to the byte slice.
+	Pad(bs []byte, blockSize int) []byte
+
+	// Unpad unpads the []byte from the byte slice.
+	Unpad(bs []byte, blockSize int) ([]byte, error)
+}

internal/padding/padding_test.go

@@ -0,0 +1,38 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import (
+	"slices"
+	"testing"
+)
+
+type testCase struct {
+	Data        []byte
+	PaddingData []byte
+}
+
+func testPadding(t *testing.T, padding Padding, testCases []testCase) {
+	blockSize := 8
+
+	for _, testCase := range testCases {
+		got := padding.Pad(testCase.Data, blockSize)
+		want := testCase.PaddingData
+
+		if !slices.Equal(got, want) {
+			t.Fatalf("got %+v != want %+v", got, want)
+		}
+
+		got, err := padding.Unpad(got, blockSize)
+		if err != nil {
+			t.Fatal(err)
+		}
+
+		want = testCase.Data
+		if !slices.Equal(got, want) {
+			t.Fatalf("got %+v != want %+v", got, want)
+		}
+	}
+}

internal/padding/pkcs5.go

@@ -0,0 +1,33 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import "fmt"
+
+type paddingPKCS5 struct{}
+
+func (paddingPKCS5) Pad(bs []byte, blockSize int) []byte {
+	padding := blockSize - (len(bs) % blockSize)
+	for i := 0; i < padding; i++ {
+		bs = append(bs, byte(padding))
+	}
+
+	return bs
+}
+
+func (paddingPKCS5) Unpad(bs []byte, blockSize int) ([]byte, error) {
+	length := len(bs)
+	number := int(bs[length-1])
+
+	if number > length {
+		return nil, fmt.Errorf("cryptox: unpad number %d > length %d", number, length)
+	}
+
+	if number > blockSize {
+		return nil, fmt.Errorf("cryptox: unpad number %d > blockSize %d", number, blockSize)
+	}
+
+	return bs[:length-number], nil
+}

internal/padding/pkcs5_test.go

@@ -0,0 +1,19 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import "testing"
+
+// go test -v -cover -run=^TestPKCS5$
+func TestPKCS5(t *testing.T) {
+	testCases := []testCase{
+		{Data: []byte{}, PaddingData: []byte{8, 8, 8, 8, 8, 8, 8, 8}},
+		{Data: []byte{1, 2, 3, 4, 5}, PaddingData: []byte{1, 2, 3, 4, 5, 3, 3, 3}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}},
+	}
+
+	testPadding(t, PKCS5, testCases)
+}

internal/padding/pkcs7.go

@@ -0,0 +1,33 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import "fmt"
+
+type paddingPKCS7 struct{}
+
+func (paddingPKCS7) Pad(bs []byte, blockSize int) []byte {
+	padding := blockSize - (len(bs) % blockSize)
+	for i := 0; i < padding; i++ {
+		bs = append(bs, byte(padding))
+	}
+
+	return bs
+}
+
+func (paddingPKCS7) Unpad(bs []byte, blockSize int) ([]byte, error) {
+	length := len(bs)
+	number := int(bs[length-1])
+
+	if number > length {
+		return nil, fmt.Errorf("cryptox: unpad number %d > length %d", number, length)
+	}
+
+	if number > blockSize {
+		return nil, fmt.Errorf("cryptox: unpad number %d > blockSize %d", number, blockSize)
+	}
+
+	return bs[:length-number], nil
+}

internal/padding/pkcs7_test.go

@@ -0,0 +1,19 @@
+// Copyright 2025 FishGoddess. All rights reserved.
+// Use of this source code is governed by a MIT style
+// license that can be found in the LICENSE file.
+
+package padding
+
+import "testing"
+
+// go test -v -cover -run=^TestPKCS7$
+func TestPKCS7(t *testing.T) {
+	testCases := []testCase{
+		{Data: []byte{}, PaddingData: []byte{8, 8, 8, 8, 8, 8, 8, 8}},
+		{Data: []byte{1, 2, 3, 4, 5}, PaddingData: []byte{1, 2, 3, 4, 5, 3, 3, 3}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8}},
+		{Data: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8}, PaddingData: []byte{1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8}},
+	}
+
+	testPadding(t, PKCS7, testCases)
+}