| // Copyright 2015 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| package cipher_test |
| |
| import ( |
| "bytes" |
| "crypto/aes" |
| "crypto/cipher" |
| "crypto/des" |
| "crypto/internal/cryptotest" |
| "fmt" |
| "testing" |
| ) |
| |
| type noopBlock int |
| |
| func (b noopBlock) BlockSize() int { return int(b) } |
| func (noopBlock) Encrypt(dst, src []byte) { copy(dst, src) } |
| func (noopBlock) Decrypt(dst, src []byte) { copy(dst, src) } |
| |
| func inc(b []byte) { |
| for i := len(b) - 1; i >= 0; i++ { |
| b[i]++ |
| if b[i] != 0 { |
| break |
| } |
| } |
| } |
| |
| func xor(a, b []byte) { |
| for i := range a { |
| a[i] ^= b[i] |
| } |
| } |
| |
| func TestCTR(t *testing.T) { |
| for size := 64; size <= 1024; size *= 2 { |
| iv := make([]byte, size) |
| ctr := cipher.NewCTR(noopBlock(size), iv) |
| src := make([]byte, 1024) |
| for i := range src { |
| src[i] = 0xff |
| } |
| want := make([]byte, 1024) |
| copy(want, src) |
| counter := make([]byte, size) |
| for i := 1; i < len(want)/size; i++ { |
| inc(counter) |
| xor(want[i*size:(i+1)*size], counter) |
| } |
| dst := make([]byte, 1024) |
| ctr.XORKeyStream(dst, src) |
| if !bytes.Equal(dst, want) { |
| t.Errorf("for size %d\nhave %x\nwant %x", size, dst, want) |
| } |
| } |
| } |
| |
| func TestCTRStream(t *testing.T) { |
| |
| for _, keylen := range []int{128, 192, 256} { |
| |
| t.Run(fmt.Sprintf("AES-%d", keylen), func(t *testing.T) { |
| rng := newRandReader(t) |
| |
| key := make([]byte, keylen/8) |
| rng.Read(key) |
| |
| block, err := aes.NewCipher(key) |
| if err != nil { |
| panic(err) |
| } |
| |
| cryptotest.TestStreamFromBlock(t, block, cipher.NewCTR) |
| }) |
| } |
| |
| t.Run("DES", func(t *testing.T) { |
| rng := newRandReader(t) |
| |
| key := make([]byte, 8) |
| rng.Read(key) |
| |
| block, err := des.NewCipher(key) |
| if err != nil { |
| panic(err) |
| } |
| |
| cryptotest.TestStreamFromBlock(t, block, cipher.NewCTR) |
| }) |
| } |