1// Copyright 2011 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
5package twofish
6
7import (
8	"bytes"
9	"testing"
10)
11
12var qbox = [2][4][16]byte{
13	{
14		{0x8, 0x1, 0x7, 0xD, 0x6, 0xF, 0x3, 0x2, 0x0, 0xB, 0x5, 0x9, 0xE, 0xC, 0xA, 0x4},
15		{0xE, 0xC, 0xB, 0x8, 0x1, 0x2, 0x3, 0x5, 0xF, 0x4, 0xA, 0x6, 0x7, 0x0, 0x9, 0xD},
16		{0xB, 0xA, 0x5, 0xE, 0x6, 0xD, 0x9, 0x0, 0xC, 0x8, 0xF, 0x3, 0x2, 0x4, 0x7, 0x1},
17		{0xD, 0x7, 0xF, 0x4, 0x1, 0x2, 0x6, 0xE, 0x9, 0xB, 0x3, 0x0, 0x8, 0x5, 0xC, 0xA},
18	},
19	{
20		{0x2, 0x8, 0xB, 0xD, 0xF, 0x7, 0x6, 0xE, 0x3, 0x1, 0x9, 0x4, 0x0, 0xA, 0xC, 0x5},
21		{0x1, 0xE, 0x2, 0xB, 0x4, 0xC, 0x3, 0x7, 0x6, 0xD, 0xA, 0x5, 0xF, 0x9, 0x0, 0x8},
22		{0x4, 0xC, 0x7, 0x5, 0x1, 0x6, 0x9, 0xA, 0x0, 0xE, 0xD, 0x8, 0x2, 0xB, 0x3, 0xF},
23		{0xB, 0x9, 0x5, 0x1, 0xC, 0x3, 0xD, 0xE, 0x6, 0x4, 0x7, 0xF, 0x2, 0x0, 0x8, 0xA},
24	},
25}
26
27// genSbox generates the variable sbox
28func genSbox(qi int, x byte) byte {
29	a0, b0 := x/16, x%16
30	for i := 0; i < 2; i++ {
31		a1 := a0 ^ b0
32		b1 := (a0 ^ ((b0 << 3) | (b0 >> 1)) ^ (a0 << 3)) & 15
33		a0 = qbox[qi][2*i][a1]
34		b0 = qbox[qi][2*i+1][b1]
35	}
36	return (b0 << 4) + a0
37}
38
39func TestSbox(t *testing.T) {
40	for n := range sbox {
41		for m := range sbox[n] {
42			if genSbox(n, byte(m)) != sbox[n][m] {
43				t.Errorf("#%d|%d: sbox value = %d want %d", n, m, sbox[n][m], genSbox(n, byte(m)))
44			}
45		}
46	}
47}
48
49var testVectors = []struct {
50	key []byte
51	dec []byte
52	enc []byte
53}{
54	// These tests are extracted from LibTom
55	{
56		[]byte{0x9F, 0x58, 0x9F, 0x5C, 0xF6, 0x12, 0x2C, 0x32, 0xB6, 0xBF, 0xEC, 0x2F, 0x2A, 0xE8, 0xC3, 0x5A},
57		[]byte{0xD4, 0x91, 0xDB, 0x16, 0xE7, 0xB1, 0xC3, 0x9E, 0x86, 0xCB, 0x08, 0x6B, 0x78, 0x9F, 0x54, 0x19},
58		[]byte{0x01, 0x9F, 0x98, 0x09, 0xDE, 0x17, 0x11, 0x85, 0x8F, 0xAA, 0xC3, 0xA3, 0xBA, 0x20, 0xFB, 0xC3},
59	},
60	{
61		[]byte{0x88, 0xB2, 0xB2, 0x70, 0x6B, 0x10, 0x5E, 0x36, 0xB4, 0x46, 0xBB, 0x6D, 0x73, 0x1A, 0x1E, 0x88,
62			0xEF, 0xA7, 0x1F, 0x78, 0x89, 0x65, 0xBD, 0x44},
63		[]byte{0x39, 0xDA, 0x69, 0xD6, 0xBA, 0x49, 0x97, 0xD5, 0x85, 0xB6, 0xDC, 0x07, 0x3C, 0xA3, 0x41, 0xB2},
64		[]byte{0x18, 0x2B, 0x02, 0xD8, 0x14, 0x97, 0xEA, 0x45, 0xF9, 0xDA, 0xAC, 0xDC, 0x29, 0x19, 0x3A, 0x65},
65	},
66	{
67		[]byte{0xD4, 0x3B, 0xB7, 0x55, 0x6E, 0xA3, 0x2E, 0x46, 0xF2, 0xA2, 0x82, 0xB7, 0xD4, 0x5B, 0x4E, 0x0D,
68			0x57, 0xFF, 0x73, 0x9D, 0x4D, 0xC9, 0x2C, 0x1B, 0xD7, 0xFC, 0x01, 0x70, 0x0C, 0xC8, 0x21, 0x6F},
69		[]byte{0x90, 0xAF, 0xE9, 0x1B, 0xB2, 0x88, 0x54, 0x4F, 0x2C, 0x32, 0xDC, 0x23, 0x9B, 0x26, 0x35, 0xE6},
70		[]byte{0x6C, 0xB4, 0x56, 0x1C, 0x40, 0xBF, 0x0A, 0x97, 0x05, 0x93, 0x1C, 0xB6, 0xD4, 0x08, 0xE7, 0xFA},
71	},
72	// These tests are derived from https://www.schneier.com/code/ecb_ival.txt
73	{
74		[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
75		[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
76		[]byte{0x9F, 0x58, 0x9F, 0x5C, 0xF6, 0x12, 0x2C, 0x32, 0xB6, 0xBF, 0xEC, 0x2F, 0x2A, 0xE8, 0xC3, 0x5A},
77	},
78	{
79		[]byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF, 0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10,
80			0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77,
81		},
82		[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
83		[]byte{0xCF, 0xD1, 0xD2, 0xE5, 0xA9, 0xBE, 0x9C, 0xDF, 0x50, 0x1F, 0x13, 0xB8, 0x92, 0xBD, 0x22, 0x48},
84	},
85	{
86		[]byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xAB, 0xCD, 0xEF, 0xFE, 0xDC, 0xBA, 0x98, 0x76, 0x54, 0x32, 0x10,
87			0x00, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, 0x99, 0xAA, 0xBB, 0xCC, 0xDD, 0xEE, 0xFF,
88		},
89		[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
90		[]byte{0x37, 0x52, 0x7B, 0xE0, 0x05, 0x23, 0x34, 0xB8, 0x9F, 0x0C, 0xFC, 0xCA, 0xE8, 0x7C, 0xFA, 0x20},
91	},
92}
93
94func TestCipher(t *testing.T) {
95	for n, tt := range testVectors {
96		// Test if the plaintext (dec) is encrypts to the given
97		// ciphertext (enc) using the given key. Test also if enc can
98		// be decrypted again into dec.
99		c, err := NewCipher(tt.key)
100		if err != nil {
101			t.Errorf("#%d: NewCipher: %v", n, err)
102			return
103		}
104
105		buf := make([]byte, 16)
106		c.Encrypt(buf, tt.dec)
107		if !bytes.Equal(buf, tt.enc) {
108			t.Errorf("#%d: encrypt = %x want %x", n, buf, tt.enc)
109		}
110		c.Decrypt(buf, tt.enc)
111		if !bytes.Equal(buf, tt.dec) {
112			t.Errorf("#%d: decrypt = %x want %x", n, buf, tt.dec)
113		}
114
115		// Test that 16 zero bytes, encrypted 1000 times then decrypted
116		// 1000 times results in zero bytes again.
117		zero := make([]byte, 16)
118		buf = make([]byte, 16)
119		for i := 0; i < 1000; i++ {
120			c.Encrypt(buf, buf)
121		}
122		for i := 0; i < 1000; i++ {
123			c.Decrypt(buf, buf)
124		}
125		if !bytes.Equal(buf, zero) {
126			t.Errorf("#%d: encrypt/decrypt 1000: have %x want %x", n, buf, zero)
127		}
128	}
129}
130