Crypto++  6.1
Free C++ class library of cryptographic schemes
sm4.cpp
1 // sm4.cpp - written and placed in the public domain by Jeffrey Walton and Han Lulu
2 //
3 // We understand future ARMv8 enhancements are supposed
4 // to include SM3 and SM4 related instructions so the function
5 // is stubbed for an eventual SM4_Round_ARMV8.
6 
7 #include "pch.h"
8 #include "config.h"
9 
10 #include "sm4.h"
11 #include "misc.h"
12 #include "cpu.h"
13 
14 ANONYMOUS_NAMESPACE_BEGIN
15 
16 using CryptoPP::byte;
17 using CryptoPP::word32;
19 
20 const byte S[256] =
21 {
22  0xD6, 0x90, 0xE9, 0xFE, 0xCC, 0xE1, 0x3D, 0xB7, 0x16, 0xB6, 0x14, 0xC2, 0x28, 0xFB, 0x2C, 0x05,
23  0x2B, 0x67, 0x9A, 0x76, 0x2A, 0xBE, 0x04, 0xC3, 0xAA, 0x44, 0x13, 0x26, 0x49, 0x86, 0x06, 0x99,
24  0x9C, 0x42, 0x50, 0xF4, 0x91, 0xEF, 0x98, 0x7A, 0x33, 0x54, 0x0B, 0x43, 0xED, 0xCF, 0xAC, 0x62,
25  0xE4, 0xB3, 0x1C, 0xA9, 0xC9, 0x08, 0xE8, 0x95, 0x80, 0xDF, 0x94, 0xFA, 0x75, 0x8F, 0x3F, 0xA6,
26  0x47, 0x07, 0xA7, 0xFC, 0xF3, 0x73, 0x17, 0xBA, 0x83, 0x59, 0x3C, 0x19, 0xE6, 0x85, 0x4F, 0xA8,
27  0x68, 0x6B, 0x81, 0xB2, 0x71, 0x64, 0xDA, 0x8B, 0xF8, 0xEB, 0x0F, 0x4B, 0x70, 0x56, 0x9D, 0x35,
28  0x1E, 0x24, 0x0E, 0x5E, 0x63, 0x58, 0xD1, 0xA2, 0x25, 0x22, 0x7C, 0x3B, 0x01, 0x21, 0x78, 0x87,
29  0xD4, 0x00, 0x46, 0x57, 0x9F, 0xD3, 0x27, 0x52, 0x4C, 0x36, 0x02, 0xE7, 0xA0, 0xC4, 0xC8, 0x9E,
30  0xEA, 0xBF, 0x8A, 0xD2, 0x40, 0xC7, 0x38, 0xB5, 0xA3, 0xF7, 0xF2, 0xCE, 0xF9, 0x61, 0x15, 0xA1,
31  0xE0, 0xAE, 0x5D, 0xA4, 0x9B, 0x34, 0x1A, 0x55, 0xAD, 0x93, 0x32, 0x30, 0xF5, 0x8C, 0xB1, 0xE3,
32  0x1D, 0xF6, 0xE2, 0x2E, 0x82, 0x66, 0xCA, 0x60, 0xC0, 0x29, 0x23, 0xAB, 0x0D, 0x53, 0x4E, 0x6F,
33  0xD5, 0xDB, 0x37, 0x45, 0xDE, 0xFD, 0x8E, 0x2F, 0x03, 0xFF, 0x6A, 0x72, 0x6D, 0x6C, 0x5B, 0x51,
34  0x8D, 0x1B, 0xAF, 0x92, 0xBB, 0xDD, 0xBC, 0x7F, 0x11, 0xD9, 0x5C, 0x41, 0x1F, 0x10, 0x5A, 0xD8,
35  0x0A, 0xC1, 0x31, 0x88, 0xA5, 0xCD, 0x7B, 0xBD, 0x2D, 0x74, 0xD0, 0x12, 0xB8, 0xE5, 0xB4, 0xB0,
36  0x89, 0x69, 0x97, 0x4A, 0x0C, 0x96, 0x77, 0x7E, 0x65, 0xB9, 0xF1, 0x09, 0xC5, 0x6E, 0xC6, 0x84,
37  0x18, 0xF0, 0x7D, 0xEC, 0x3A, 0xDC, 0x4D, 0x20, 0x79, 0xEE, 0x5F, 0x3E, 0xD7, 0xCB, 0x39, 0x48
38 };
39 
40 const word32 CK[32] =
41 {
42  0x00070E15, 0x1C232A31, 0x383F464D, 0x545B6269,
43  0x70777E85, 0x8C939AA1, 0xA8AFB6BD, 0xC4CBD2D9,
44  0xE0E7EEF5, 0xFC030A11, 0x181F262D, 0x343B4249,
45  0x50575E65, 0x6C737A81, 0x888F969D, 0xA4ABB2B9,
46  0xC0C7CED5, 0xDCE3EAF1, 0xF8FF060D, 0x141B2229,
47  0x30373E45, 0x4C535A61, 0x686F767D, 0x848B9299,
48  0xA0A7AEB5, 0xBCC3CAD1, 0xD8DFE6ED, 0xF4FB0209,
49  0x10171E25, 0x2C333A41, 0x484F565D, 0x646B7279
50 };
51 
52 inline word32 SM4_H(word32 x)
53 {
54  return (S[GETBYTE(x, 3)] << 24) | (S[GETBYTE(x, 2)] << 16) | (S[GETBYTE(x, 1)] << 8) | (S[GETBYTE(x, 0)]);
55 }
56 
57 inline word32 SM4_G(word32 x)
58 {
59  const word32 t = SM4_H(x);
60  return t ^ rotlConstant<13>(t) ^ rotlConstant<23>(t);
61 }
62 
63 inline word32 SM4_F(word32 x)
64 {
65  const word32 t = SM4_H(x);
66  return t ^ rotlConstant<2>(t) ^ rotlConstant<10>(t) ^ rotlConstant<18>(t) ^ rotlConstant<24>(t);
67 }
68 
69 template <unsigned int R, bool FWD>
70 inline void SM4_Round(word32 wspace[4], const word32 rkeys[32])
71 {
72  if (FWD)
73  {
74  wspace[0] ^= SM4_F(wspace[1] ^ wspace[2] ^ wspace[3] ^ rkeys[R+0]);
75  wspace[1] ^= SM4_F(wspace[0] ^ wspace[2] ^ wspace[3] ^ rkeys[R+1]);
76  wspace[2] ^= SM4_F(wspace[0] ^ wspace[1] ^ wspace[3] ^ rkeys[R+2]);
77  wspace[3] ^= SM4_F(wspace[0] ^ wspace[1] ^ wspace[2] ^ rkeys[R+3]);
78  }
79  else
80  {
81  wspace[0] ^= SM4_F(wspace[1] ^ wspace[2] ^ wspace[3] ^ rkeys[R-0]);
82  wspace[1] ^= SM4_F(wspace[0] ^ wspace[2] ^ wspace[3] ^ rkeys[R-1]);
83  wspace[2] ^= SM4_F(wspace[0] ^ wspace[1] ^ wspace[3] ^ rkeys[R-2]);
84  wspace[3] ^= SM4_F(wspace[0] ^ wspace[1] ^ wspace[2] ^ rkeys[R-3]);
85  }
86 }
87 
88 ANONYMOUS_NAMESPACE_END
89 
90 NAMESPACE_BEGIN(CryptoPP)
91 
92 void SM4::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)
93 {
94  CRYPTOPP_ASSERT(keyLength == 16);
95  CRYPTOPP_UNUSED(params);
96 
97  m_rkeys.New(32);
98  m_wspace.New(5);
99 
100  GetUserKey(BIG_ENDIAN_ORDER, m_wspace.begin(), 4, userKey, keyLength);
101  m_wspace[0] ^= 0xa3b1bac6; m_wspace[1] ^= 0x56aa3350;
102  m_wspace[2] ^= 0x677d9197; m_wspace[3] ^= 0xb27022dc;
103 
104  size_t i=0;
105  do
106  {
107  m_rkeys[i] = (m_wspace[0] ^= SM4_G(m_wspace[1] ^ m_wspace[2] ^ m_wspace[3] ^ CK[i])); i++;
108  m_rkeys[i] = (m_wspace[1] ^= SM4_G(m_wspace[2] ^ m_wspace[3] ^ m_wspace[0] ^ CK[i])); i++;
109  m_rkeys[i] = (m_wspace[2] ^= SM4_G(m_wspace[3] ^ m_wspace[0] ^ m_wspace[1] ^ CK[i])); i++;
110  m_rkeys[i] = (m_wspace[3] ^= SM4_G(m_wspace[0] ^ m_wspace[1] ^ m_wspace[2] ^ CK[i])); i++;
111  }
112  while (i < 32);
113 }
114 
115 void SM4::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
116 {
117  // Reverse bytes on LittleEndian; align pointer on BigEndian
118  typedef GetBlock<word32, BigEndian, false> InBlock;
119  InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1])(m_wspace[2])(m_wspace[3]);
120 
121  // Timing attack countermeasure, see comments in Rijndael for more details.
122  // The hardening does not materially affect benchmarks. SM4 runs at
123  // 30.5 cpb on a Core i5 Skylake with and without the code below.
124  const int cacheLineSize = GetCacheLineSize();
125  volatile word32 _u = 0;
126  word32 u = _u;
127 
128  for (unsigned int i=0; i<sizeof(S); i+=cacheLineSize)
129  u |= *(const word32 *)(void*)(S+i);
130  m_wspace[4] = u;
131 
132  SM4_Round< 0, true>(m_wspace, m_rkeys);
133  SM4_Round< 4, true>(m_wspace, m_rkeys);
134  SM4_Round< 8, true>(m_wspace, m_rkeys);
135  SM4_Round<12, true>(m_wspace, m_rkeys);
136  SM4_Round<16, true>(m_wspace, m_rkeys);
137  SM4_Round<20, true>(m_wspace, m_rkeys);
138  SM4_Round<24, true>(m_wspace, m_rkeys);
139  SM4_Round<28, true>(m_wspace, m_rkeys);
140 
141  // Reverse bytes on LittleEndian; align pointer on BigEndian
142  typedef PutBlock<word32, BigEndian, false> OutBlock;
143  OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[3])(m_wspace[2])(m_wspace[1])(m_wspace[0]);
144 }
145 
146 void SM4::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const
147 {
148  // Reverse bytes on LittleEndian; align pointer on BigEndian
149  typedef GetBlock<word32, BigEndian, false> InBlock;
150  InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1])(m_wspace[2])(m_wspace[3]);
151 
152  // Timing attack countermeasure, see comments in Rijndael for more details.
153  // The hardening does not materially affect benchmarks. SM4 runs at
154  // 30.5 cpb on a Core i5 Skylake with and without the code below.
155  const int cacheLineSize = GetCacheLineSize();
156  volatile word32 _u = 0;
157  word32 u = _u;
158 
159  for (unsigned int i=0; i<sizeof(S); i+=cacheLineSize)
160  u |= *(const word32 *)(void*)(S+i);
161  m_wspace[4] = u;
162 
163  SM4_Round<31, false>(m_wspace, m_rkeys);
164  SM4_Round<27, false>(m_wspace, m_rkeys);
165  SM4_Round<23, false>(m_wspace, m_rkeys);
166  SM4_Round<19, false>(m_wspace, m_rkeys);
167  SM4_Round<15, false>(m_wspace, m_rkeys);
168  SM4_Round<11, false>(m_wspace, m_rkeys);
169  SM4_Round< 7, false>(m_wspace, m_rkeys);
170  SM4_Round< 3, false>(m_wspace, m_rkeys);
171 
172  // Reverse bytes on LittleEndian; align pointer on BigEndian
173  typedef PutBlock<word32, BigEndian, false> OutBlock;
174  OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[3])(m_wspace[2])(m_wspace[1])(m_wspace[0]);
175 }
176 
177 NAMESPACE_END
Utility functions for the Crypto++ library.
Library configuration file.
int GetCacheLineSize()
Provides the cache line size.
Definition: cpu.h:298
void New(size_type newSize)
Change size without preserving contents.
Definition: secblock.h:729
T rotlConstant(T x)
Performs a left rotate.
Definition: misc.h:1365
Precompiled header file.
byte order is big-endian
Definition: cryptlib.h:144
#define CRYPTOPP_ASSERT(exp)
Debugging and diagnostic assertion.
Definition: trap.h:60
Functions for CPU features and intrinsics.
iterator begin()
Provides an iterator pointing to the first element in the memory block.
Definition: secblock.h:536
Classes for the SM4 block cipher.
Access a block of memory.
Definition: misc.h:2324
Access a block of memory.
Definition: misc.h:2365
Crypto++ library namespace.
Interface for retrieving values given their names.
Definition: cryptlib.h:290