1 /* Aes.c -- AES encryption / decryption 2 2017-01-24 : Igor Pavlov : Public domain */ 3 4 #include "Precomp.h" 5 6 #include "Aes.h" 7 #include "CpuArch.h" 8 9 static UInt32 T[256 * 4]; 10 static const Byte Sbox[256] = { 11 0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, 12 0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, 13 0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, 14 0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, 15 0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, 16 0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, 17 0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, 18 0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, 19 0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, 20 0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, 21 0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, 22 0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, 23 0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, 24 0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, 25 0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, 26 0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16}; 27 28 void MY_FAST_CALL AesCbc_Encode(UInt32 *ivAes, Byte *data, size_t numBlocks); 29 void MY_FAST_CALL AesCbc_Decode(UInt32 *ivAes, Byte *data, size_t numBlocks); 30 void MY_FAST_CALL AesCtr_Code(UInt32 *ivAes, Byte *data, size_t numBlocks); 31 32 void MY_FAST_CALL AesCbc_Encode_Intel(UInt32 *ivAes, Byte *data, size_t numBlocks); 33 void MY_FAST_CALL AesCbc_Decode_Intel(UInt32 *ivAes, Byte *data, size_t numBlocks); 34 void MY_FAST_CALL AesCtr_Code_Intel(UInt32 *ivAes, Byte *data, size_t numBlocks); 35 36 AES_CODE_FUNC g_AesCbc_Encode; 37 AES_CODE_FUNC g_AesCbc_Decode; 38 AES_CODE_FUNC g_AesCtr_Code; 39 40 static UInt32 D[256 * 4]; 41 static Byte InvS[256]; 42 43 static const Byte Rcon[11] = { 0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 }; 44 45 #define xtime(x) ((((x) << 1) ^ (((x) & 0x80) != 0 ? 0x1B : 0)) & 0xFF) 46 47 #define Ui32(a0, a1, a2, a3) ((UInt32)(a0) | ((UInt32)(a1) << 8) | ((UInt32)(a2) << 16) | ((UInt32)(a3) << 24)) 48 49 #define gb0(x) ( (x) & 0xFF) 50 #define gb1(x) (((x) >> ( 8)) & 0xFF) 51 #define gb2(x) (((x) >> (16)) & 0xFF) 52 #define gb3(x) (((x) >> (24))) 53 54 #define gb(n, x) gb ## n(x) 55 56 #define TT(x) (T + (x << 8)) 57 #define DD(x) (D + (x << 8)) 58 59 60 void AesGenTables(void) 61 { 62 unsigned i; 63 for (i = 0; i < 256; i++) 64 InvS[Sbox[i]] = (Byte)i; 65 66 for (i = 0; i < 256; i++) 67 { 68 { 69 UInt32 a1 = Sbox[i]; 70 UInt32 a2 = xtime(a1); 71 UInt32 a3 = a2 ^ a1; 72 TT(0)[i] = Ui32(a2, a1, a1, a3); 73 TT(1)[i] = Ui32(a3, a2, a1, a1); 74 TT(2)[i] = Ui32(a1, a3, a2, a1); 75 TT(3)[i] = Ui32(a1, a1, a3, a2); 76 } 77 { 78 UInt32 a1 = InvS[i]; 79 UInt32 a2 = xtime(a1); 80 UInt32 a4 = xtime(a2); 81 UInt32 a8 = xtime(a4); 82 UInt32 a9 = a8 ^ a1; 83 UInt32 aB = a8 ^ a2 ^ a1; 84 UInt32 aD = a8 ^ a4 ^ a1; 85 UInt32 aE = a8 ^ a4 ^ a2; 86 DD(0)[i] = Ui32(aE, a9, aD, aB); 87 DD(1)[i] = Ui32(aB, aE, a9, aD); 88 DD(2)[i] = Ui32(aD, aB, aE, a9); 89 DD(3)[i] = Ui32(a9, aD, aB, aE); 90 } 91 } 92 93 g_AesCbc_Encode = AesCbc_Encode; 94 g_AesCbc_Decode = AesCbc_Decode; 95 g_AesCtr_Code = AesCtr_Code; 96 97 #ifdef MY_CPU_X86_OR_AMD64 98 if (CPU_Is_Aes_Supported()) 99 { 100 g_AesCbc_Encode = AesCbc_Encode_Intel; 101 g_AesCbc_Decode = AesCbc_Decode_Intel; 102 g_AesCtr_Code = AesCtr_Code_Intel; 103 } 104 #endif 105 } 106 107 108 #define HT(i, x, s) TT(x)[gb(x, s[(i + x) & 3])] 109 110 #define HT4(m, i, s, p) m[i] = \ 111 HT(i, 0, s) ^ \ 112 HT(i, 1, s) ^ \ 113 HT(i, 2, s) ^ \ 114 HT(i, 3, s) ^ w[p + i] 115 116 #define HT16(m, s, p) \ 117 HT4(m, 0, s, p); \ 118 HT4(m, 1, s, p); \ 119 HT4(m, 2, s, p); \ 120 HT4(m, 3, s, p); \ 121 122 #define FT(i, x) Sbox[gb(x, m[(i + x) & 3])] 123 #define FT4(i) dest[i] = Ui32(FT(i, 0), FT(i, 1), FT(i, 2), FT(i, 3)) ^ w[i]; 124 125 126 #define HD(i, x, s) DD(x)[gb(x, s[(i - x) & 3])] 127 128 #define HD4(m, i, s, p) m[i] = \ 129 HD(i, 0, s) ^ \ 130 HD(i, 1, s) ^ \ 131 HD(i, 2, s) ^ \ 132 HD(i, 3, s) ^ w[p + i]; 133 134 #define HD16(m, s, p) \ 135 HD4(m, 0, s, p); \ 136 HD4(m, 1, s, p); \ 137 HD4(m, 2, s, p); \ 138 HD4(m, 3, s, p); \ 139 140 #define FD(i, x) InvS[gb(x, m[(i - x) & 3])] 141 #define FD4(i) dest[i] = Ui32(FD(i, 0), FD(i, 1), FD(i, 2), FD(i, 3)) ^ w[i]; 142 143 void MY_FAST_CALL Aes_SetKey_Enc(UInt32 *w, const Byte *key, unsigned keySize) 144 { 145 unsigned i, wSize; 146 wSize = keySize + 28; 147 keySize /= 4; 148 w[0] = ((UInt32)keySize / 2) + 3; 149 w += 4; 150 151 for (i = 0; i < keySize; i++, key += 4) 152 w[i] = GetUi32(key); 153 154 for (; i < wSize; i++) 155 { 156 UInt32 t = w[(size_t)i - 1]; 157 unsigned rem = i % keySize; 158 if (rem == 0) 159 t = Ui32(Sbox[gb1(t)] ^ Rcon[i / keySize], Sbox[gb2(t)], Sbox[gb3(t)], Sbox[gb0(t)]); 160 else if (keySize > 6 && rem == 4) 161 t = Ui32(Sbox[gb0(t)], Sbox[gb1(t)], Sbox[gb2(t)], Sbox[gb3(t)]); 162 w[i] = w[i - keySize] ^ t; 163 } 164 } 165 166 void MY_FAST_CALL Aes_SetKey_Dec(UInt32 *w, const Byte *key, unsigned keySize) 167 { 168 unsigned i, num; 169 Aes_SetKey_Enc(w, key, keySize); 170 num = keySize + 20; 171 w += 8; 172 for (i = 0; i < num; i++) 173 { 174 UInt32 r = w[i]; 175 w[i] = 176 DD(0)[Sbox[gb0(r)]] ^ 177 DD(1)[Sbox[gb1(r)]] ^ 178 DD(2)[Sbox[gb2(r)]] ^ 179 DD(3)[Sbox[gb3(r)]]; 180 } 181 } 182 183 /* Aes_Encode and Aes_Decode functions work with little-endian words. 184 src and dest are pointers to 4 UInt32 words. 185 src and dest can point to same block */ 186 187 static void Aes_Encode(const UInt32 *w, UInt32 *dest, const UInt32 *src) 188 { 189 UInt32 s[4]; 190 UInt32 m[4]; 191 UInt32 numRounds2 = w[0]; 192 w += 4; 193 s[0] = src[0] ^ w[0]; 194 s[1] = src[1] ^ w[1]; 195 s[2] = src[2] ^ w[2]; 196 s[3] = src[3] ^ w[3]; 197 w += 4; 198 for (;;) 199 { 200 HT16(m, s, 0); 201 if (--numRounds2 == 0) 202 break; 203 HT16(s, m, 4); 204 w += 8; 205 } 206 w += 4; 207 FT4(0); FT4(1); FT4(2); FT4(3); 208 } 209 210 static void Aes_Decode(const UInt32 *w, UInt32 *dest, const UInt32 *src) 211 { 212 UInt32 s[4]; 213 UInt32 m[4]; 214 UInt32 numRounds2 = w[0]; 215 w += 4 + numRounds2 * 8; 216 s[0] = src[0] ^ w[0]; 217 s[1] = src[1] ^ w[1]; 218 s[2] = src[2] ^ w[2]; 219 s[3] = src[3] ^ w[3]; 220 for (;;) 221 { 222 w -= 8; 223 HD16(m, s, 4); 224 if (--numRounds2 == 0) 225 break; 226 HD16(s, m, 0); 227 } 228 FD4(0); FD4(1); FD4(2); FD4(3); 229 } 230 231 void AesCbc_Init(UInt32 *p, const Byte *iv) 232 { 233 unsigned i; 234 for (i = 0; i < 4; i++) 235 p[i] = GetUi32(iv + i * 4); 236 } 237 238 void MY_FAST_CALL AesCbc_Encode(UInt32 *p, Byte *data, size_t numBlocks) 239 { 240 for (; numBlocks != 0; numBlocks--, data += AES_BLOCK_SIZE) 241 { 242 p[0] ^= GetUi32(data); 243 p[1] ^= GetUi32(data + 4); 244 p[2] ^= GetUi32(data + 8); 245 p[3] ^= GetUi32(data + 12); 246 247 Aes_Encode(p + 4, p, p); 248 249 SetUi32(data, p[0]); 250 SetUi32(data + 4, p[1]); 251 SetUi32(data + 8, p[2]); 252 SetUi32(data + 12, p[3]); 253 } 254 } 255 256 void MY_FAST_CALL AesCbc_Decode(UInt32 *p, Byte *data, size_t numBlocks) 257 { 258 UInt32 in[4], out[4]; 259 for (; numBlocks != 0; numBlocks--, data += AES_BLOCK_SIZE) 260 { 261 in[0] = GetUi32(data); 262 in[1] = GetUi32(data + 4); 263 in[2] = GetUi32(data + 8); 264 in[3] = GetUi32(data + 12); 265 266 Aes_Decode(p + 4, out, in); 267 268 SetUi32(data, p[0] ^ out[0]); 269 SetUi32(data + 4, p[1] ^ out[1]); 270 SetUi32(data + 8, p[2] ^ out[2]); 271 SetUi32(data + 12, p[3] ^ out[3]); 272 273 p[0] = in[0]; 274 p[1] = in[1]; 275 p[2] = in[2]; 276 p[3] = in[3]; 277 } 278 } 279 280 void MY_FAST_CALL AesCtr_Code(UInt32 *p, Byte *data, size_t numBlocks) 281 { 282 for (; numBlocks != 0; numBlocks--) 283 { 284 UInt32 temp[4]; 285 unsigned i; 286 287 if (++p[0] == 0) 288 p[1]++; 289 290 Aes_Encode(p + 4, temp, p); 291 292 for (i = 0; i < 4; i++, data += 4) 293 { 294 UInt32 t = temp[i]; 295 296 #ifdef MY_CPU_LE_UNALIGN 297 *((UInt32 *)data) ^= t; 298 #else 299 data[0] ^= (t & 0xFF); 300 data[1] ^= ((t >> 8) & 0xFF); 301 data[2] ^= ((t >> 16) & 0xFF); 302 data[3] ^= ((t >> 24)); 303 #endif 304 } 305 } 306 } 307
