Source file src/crypto/cipher/cfb_test.go

     1  // Copyright 2010 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package cipher_test
     6  
     7  import (
     8  	"bytes"
     9  	"crypto/aes"
    10  	"crypto/cipher"
    11  	"crypto/des"
    12  	"crypto/internal/cryptotest"
    13  	"crypto/rand"
    14  	"encoding/hex"
    15  	"fmt"
    16  	"testing"
    17  )
    18  
    19  // cfbTests contains the test vectors from
    20  // https://csrc.nist.gov/publications/nistpubs/800-38a/sp800-38a.pdf, section
    21  // F.3.13.
    22  var cfbTests = []struct {
    23  	key, iv, plaintext, ciphertext string
    24  }{
    25  	{
    26  		"2b7e151628aed2a6abf7158809cf4f3c",
    27  		"000102030405060708090a0b0c0d0e0f",
    28  		"6bc1bee22e409f96e93d7e117393172a",
    29  		"3b3fd92eb72dad20333449f8e83cfb4a",
    30  	},
    31  	{
    32  		"2b7e151628aed2a6abf7158809cf4f3c",
    33  		"3B3FD92EB72DAD20333449F8E83CFB4A",
    34  		"ae2d8a571e03ac9c9eb76fac45af8e51",
    35  		"c8a64537a0b3a93fcde3cdad9f1ce58b",
    36  	},
    37  	{
    38  		"2b7e151628aed2a6abf7158809cf4f3c",
    39  		"C8A64537A0B3A93FCDE3CDAD9F1CE58B",
    40  		"30c81c46a35ce411e5fbc1191a0a52ef",
    41  		"26751f67a3cbb140b1808cf187a4f4df",
    42  	},
    43  	{
    44  		"2b7e151628aed2a6abf7158809cf4f3c",
    45  		"26751F67A3CBB140B1808CF187A4F4DF",
    46  		"f69f2445df4f9b17ad2b417be66c3710",
    47  		"c04b05357c5d1c0eeac4c66f9ff7f2e6",
    48  	},
    49  }
    50  
    51  func TestCFBVectors(t *testing.T) {
    52  	for i, test := range cfbTests {
    53  		key, err := hex.DecodeString(test.key)
    54  		if err != nil {
    55  			t.Fatal(err)
    56  		}
    57  		iv, err := hex.DecodeString(test.iv)
    58  		if err != nil {
    59  			t.Fatal(err)
    60  		}
    61  		plaintext, err := hex.DecodeString(test.plaintext)
    62  		if err != nil {
    63  			t.Fatal(err)
    64  		}
    65  		expected, err := hex.DecodeString(test.ciphertext)
    66  		if err != nil {
    67  			t.Fatal(err)
    68  		}
    69  
    70  		block, err := aes.NewCipher(key)
    71  		if err != nil {
    72  			t.Fatal(err)
    73  		}
    74  
    75  		ciphertext := make([]byte, len(plaintext))
    76  		cfb := cipher.NewCFBEncrypter(block, iv)
    77  		cfb.XORKeyStream(ciphertext, plaintext)
    78  
    79  		if !bytes.Equal(ciphertext, expected) {
    80  			t.Errorf("#%d: wrong output: got %x, expected %x", i, ciphertext, expected)
    81  		}
    82  
    83  		cfbdec := cipher.NewCFBDecrypter(block, iv)
    84  		plaintextCopy := make([]byte, len(ciphertext))
    85  		cfbdec.XORKeyStream(plaintextCopy, ciphertext)
    86  
    87  		if !bytes.Equal(plaintextCopy, plaintext) {
    88  			t.Errorf("#%d: wrong plaintext: got %x, expected %x", i, plaintextCopy, plaintext)
    89  		}
    90  	}
    91  }
    92  
    93  func TestCFBInverse(t *testing.T) {
    94  	block, err := aes.NewCipher(commonKey128)
    95  	if err != nil {
    96  		t.Error(err)
    97  		return
    98  	}
    99  
   100  	plaintext := []byte("this is the plaintext. this is the plaintext.")
   101  	iv := make([]byte, block.BlockSize())
   102  	rand.Reader.Read(iv)
   103  	cfb := cipher.NewCFBEncrypter(block, iv)
   104  	ciphertext := make([]byte, len(plaintext))
   105  	copy(ciphertext, plaintext)
   106  	cfb.XORKeyStream(ciphertext, ciphertext)
   107  
   108  	cfbdec := cipher.NewCFBDecrypter(block, iv)
   109  	plaintextCopy := make([]byte, len(plaintext))
   110  	copy(plaintextCopy, ciphertext)
   111  	cfbdec.XORKeyStream(plaintextCopy, plaintextCopy)
   112  
   113  	if !bytes.Equal(plaintextCopy, plaintext) {
   114  		t.Errorf("got: %x, want: %x", plaintextCopy, plaintext)
   115  	}
   116  }
   117  
   118  func TestCFBStream(t *testing.T) {
   119  
   120  	for _, keylen := range []int{128, 192, 256} {
   121  
   122  		t.Run(fmt.Sprintf("AES-%d", keylen), func(t *testing.T) {
   123  			rng := newRandReader(t)
   124  
   125  			key := make([]byte, keylen/8)
   126  			rng.Read(key)
   127  
   128  			block, err := aes.NewCipher(key)
   129  			if err != nil {
   130  				panic(err)
   131  			}
   132  
   133  			t.Run("Encrypter", func(t *testing.T) {
   134  				cryptotest.TestStreamFromBlock(t, block, cipher.NewCFBEncrypter)
   135  			})
   136  			t.Run("Decrypter", func(t *testing.T) {
   137  				cryptotest.TestStreamFromBlock(t, block, cipher.NewCFBDecrypter)
   138  			})
   139  		})
   140  	}
   141  
   142  	t.Run("DES", func(t *testing.T) {
   143  		rng := newRandReader(t)
   144  
   145  		key := make([]byte, 8)
   146  		rng.Read(key)
   147  
   148  		block, err := des.NewCipher(key)
   149  		if err != nil {
   150  			panic(err)
   151  		}
   152  
   153  		t.Run("Encrypter", func(t *testing.T) {
   154  			cryptotest.TestStreamFromBlock(t, block, cipher.NewCFBEncrypter)
   155  		})
   156  		t.Run("Decrypter", func(t *testing.T) {
   157  			cryptotest.TestStreamFromBlock(t, block, cipher.NewCFBDecrypter)
   158  		})
   159  	})
   160  }
   161  

View as plain text