aboutsummaryrefslogtreecommitdiffstats
path: root/src/lib/block/sm4/sm4.cpp
blob: 9794915667313b8d0a95bc9fc7268815c94bda0f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
/*
* SM4
* (C) 2017 Ribose Inc
*
* Botan is released under the Simplified BSD License (see license.txt)
*/

#include <botan/sm4.h>
#include <botan/loadstor.h>

namespace Botan {

namespace SM4_F {

const uint8_t SBOX[256] = {
0xD6, 0x90, 0xE9, 0xFE, 0xCC, 0xE1, 0x3D, 0xB7, 0x16, 0xB6, 0x14, 0xC2, 0x28, 0xFB, 0x2C, 0x05,
0x2B, 0x67, 0x9A, 0x76, 0x2A, 0xBE, 0x04, 0xC3, 0xAA, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99,
0x9C, 0x42, 0x50, 0xF4, 0x91, 0xEF, 0x98, 0x7A, 0x33, 0x54, 0x0B, 0x43, 0xED, 0xCF, 0xAC, 0x62,
0xE4, 0xB3, 0x1C, 0xA9, 0xC9, 0x08, 0xE8, 0x95, 0x80, 0xDF, 0x94, 0xFA, 0x75, 0x8F, 0x3F, 0xA6,
0x47, 0x07, 0xA7, 0xFC, 0xF3, 0x73, 0x17, 0xBA, 0x83, 0x59, 0x3C, 0x19, 0xE6, 0x85, 0x4F, 0xA8,
0x68, 0x6B, 0x81, 0xB2, 0x71, 0x64, 0xDA, 0x8B, 0xF8, 0xEB, 0x0F, 0x4B, 0x70, 0x56, 0x9D, 0x35,
0x1E, 0x24, 0x0E, 0x5E, 0x63, 0x58, 0xD1, 0xA2, 0x25, 0x22, 0x7C, 0x3B, 0x01, 0x21, 0x78, 0x87,
0xD4, 0x00, 0x46, 0x57, 0x9F, 0xD3, 0x27, 0x52, 0x4C, 0x36, 0x02, 0xE7, 0xA0, 0xC4, 0xC8, 0x9E,
0xEA, 0xBF, 0x8A, 0xD2, 0x40, 0xC7, 0x38, 0xB5, 0xA3, 0xF7, 0xF2, 0xCE, 0xF9, 0x61, 0x15, 0xA1,
0xE0, 0xAE, 0x5D, 0xA4, 0x9B, 0x34, 0x1A, 0x55, 0xAD, 0x93, 0x32, 0x30, 0xF5, 0x8C, 0xB1, 0xE3,
0x1D, 0xF6, 0xE2, 0x2E, 0x82, 0x66, 0xCA, 0x60, 0xC0, 0x29, 0x23, 0xAB, 0x0D, 0x53, 0x4E, 0x6F,
0xD5, 0xDB, 0x37, 0x45, 0xDE, 0xFD, 0x8E, 0x2F, 0x03, 0xFF, 0x6A, 0x72, 0x6D, 0x6C, 0x5B, 0x51,
0x8D, 0x1B, 0xAF, 0x92, 0xBB, 0xDD, 0xBC, 0x7F, 0x11, 0xD9, 0x5C, 0x41, 0x1F, 0x10, 0x5A, 0xD8,
0x0A, 0xC1, 0x31, 0x88, 0xA5, 0xCD, 0x7B, 0xBD, 0x2D, 0x74, 0xD0, 0x12, 0xB8, 0xE5, 0xB4, 0xB0,
0x89, 0x69, 0x97, 0x4A, 0x0C, 0x96, 0x77, 0x7E, 0x65, 0xB9, 0xF1, 0x09, 0xC5, 0x6E, 0xC6, 0x84,
0x18, 0xF0, 0x7D, 0xEC, 0x3A, 0xDC, 0x4D, 0x20, 0x79, 0xEE, 0x5F, 0x3E, 0xD7, 0xCB, 0x39, 0x48
};

inline uint32_t T(uint32_t b)
   {
   /*
   TODO: could convert this to 4 8->32 bit tables combined with xor.
   It was about 66% faster (110 MiB->181 MiB) on an i7-6700k, but the
   large tables will be likely vulnerable to AES style cache attacks.
   */

   const uint8_t b0 = get_byte(0, b);
   const uint8_t b1 = get_byte(1, b);
   const uint8_t b2 = get_byte(2, b);
   const uint8_t b3 = get_byte(3, b);
   const uint32_t t = make_uint32(SBOX[b0], SBOX[b1], SBOX[b2], SBOX[b3]);

   // L linear transform
   return t ^ rotate_left(t, 2) ^ rotate_left(t, 10) ^ rotate_left(t, 18) ^ rotate_left(t, 24);
   }

// Variant of T for key schedule
inline uint32_t Tp(uint32_t b)
   {
   const uint8_t b0 = get_byte(0, b);
   const uint8_t b1 = get_byte(1, b);
   const uint8_t b2 = get_byte(2, b);
   const uint8_t b3 = get_byte(3, b);
   const uint32_t t = make_uint32(SBOX[b0], SBOX[b1], SBOX[b2], SBOX[b3]);

   // L' linear transform
   return t ^ rotate_left(t, 13) ^ rotate_left(t, 23);
   }

}

/*
* SM4 Encryption
*/
void SM4::encrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const
   {
   for(size_t i = 0; i != blocks; ++i)
      {
      uint32_t B0 = load_be<uint32_t>(in, 0);
      uint32_t B1 = load_be<uint32_t>(in, 1);
      uint32_t B2 = load_be<uint32_t>(in, 2);
      uint32_t B3 = load_be<uint32_t>(in, 3);

      for(size_t r = 0; r != 32; r += 4)
         {
         B0 ^= SM4_F::T(B1 ^ B2 ^ B3 ^ m_RK[r + 0]);
         B1 ^= SM4_F::T(B0 ^ B2 ^ B3 ^ m_RK[r + 1]);
         B2 ^= SM4_F::T(B0 ^ B1 ^ B3 ^ m_RK[r + 2]);
         B3 ^= SM4_F::T(B0 ^ B1 ^ B2 ^ m_RK[r + 3]);
         }

      store_be(out, B3, B2, B1, B0);

      in += BLOCK_SIZE;
      out += BLOCK_SIZE;
      }
   }

/*
* SM4 Decryption
*/
void SM4::decrypt_n(const uint8_t in[], uint8_t out[], size_t blocks) const
   {
   for(size_t i = 0; i != blocks; ++i)
      {
      uint32_t B0 = load_be<uint32_t>(in, 0);
      uint32_t B1 = load_be<uint32_t>(in, 1);
      uint32_t B2 = load_be<uint32_t>(in, 2);
      uint32_t B3 = load_be<uint32_t>(in, 3);

      for(size_t r = 0; r != 32; r += 4)
         {
         B0 ^= SM4_F::T(B1 ^ B2 ^ B3 ^ m_RK[31 - (r + 0)]);
         B1 ^= SM4_F::T(B0 ^ B2 ^ B3 ^ m_RK[31 - (r + 1)]);
         B2 ^= SM4_F::T(B0 ^ B1 ^ B3 ^ m_RK[31 - (r + 2)]);
         B3 ^= SM4_F::T(B0 ^ B1 ^ B2 ^ m_RK[31 - (r + 3)]);
         }

      store_be(out, B3, B2, B1, B0);

      in += BLOCK_SIZE;
      out += BLOCK_SIZE;
      }
   }

/*
* SM4 Key Schedule
*/
void SM4::key_schedule(const uint8_t key[], size_t)
   {
   // System parameter or family key
   const uint32_t FK[4] = { 0xa3b1bac6, 0x56aa3350, 0x677d9197, 0xb27022dc };

   const uint32_t CK[32] = {
      0x00070E15, 0x1C232A31, 0x383F464D, 0x545B6269,
      0x70777E85, 0x8C939AA1, 0xA8AFB6BD, 0xC4CBD2D9,
      0xE0E7EEF5, 0xFC030A11, 0x181F262D, 0x343B4249,
      0x50575E65, 0x6C737A81, 0x888F969D, 0xA4ABB2B9,
      0xC0C7CED5, 0xDCE3EAF1, 0xF8FF060D, 0x141B2229,
      0x30373E45, 0x4C535A61, 0x686F767D, 0x848B9299,
      0xA0A7AEB5, 0xBCC3CAD1, 0xD8DFE6ED, 0xF4FB0209,
      0x10171E25, 0x2C333A41, 0x484F565D, 0x646B7279
   };

   secure_vector<uint32_t> K(4);
   K[0] = load_be<uint32_t>(key, 0) ^ FK[0];
   K[1] = load_be<uint32_t>(key, 1) ^ FK[1];
   K[2] = load_be<uint32_t>(key, 2) ^ FK[2];
   K[3] = load_be<uint32_t>(key, 3) ^ FK[3];

   m_RK.resize(32);
   for(size_t i = 0; i != 32; ++i)
      {
      K[i % 4] ^= SM4_F::Tp(K[(i+1)%4] ^ K[(i+2)%4] ^ K[(i+3)%4] ^ CK[i]);
      m_RK[i] = K[i % 4];
      }
   }

void SM4::clear()
   {
   zap(m_RK);
   }

}