2 * Copyright (c) 2016 Thomas Pornin <pornin@bolet.org>
4 * Permission is hereby granted, free of charge, to any person obtaining
5 * a copy of this software and associated documentation files (the
6 * "Software"), to deal in the Software without restriction, including
7 * without limitation the rights to use, copy, modify, merge, publish,
8 * distribute, sublicense, and/or sell copies of the Software, and to
9 * permit persons to whom the Software is furnished to do so, subject to
10 * the following conditions:
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30 static const unsigned char iS
[] = {
31 0x52, 0x09, 0x6A, 0xD5, 0x30, 0x36, 0xA5, 0x38, 0xBF, 0x40, 0xA3, 0x9E,
32 0x81, 0xF3, 0xD7, 0xFB, 0x7C, 0xE3, 0x39, 0x82, 0x9B, 0x2F, 0xFF, 0x87,
33 0x34, 0x8E, 0x43, 0x44, 0xC4, 0xDE, 0xE9, 0xCB, 0x54, 0x7B, 0x94, 0x32,
34 0xA6, 0xC2, 0x23, 0x3D, 0xEE, 0x4C, 0x95, 0x0B, 0x42, 0xFA, 0xC3, 0x4E,
35 0x08, 0x2E, 0xA1, 0x66, 0x28, 0xD9, 0x24, 0xB2, 0x76, 0x5B, 0xA2, 0x49,
36 0x6D, 0x8B, 0xD1, 0x25, 0x72, 0xF8, 0xF6, 0x64, 0x86, 0x68, 0x98, 0x16,
37 0xD4, 0xA4, 0x5C, 0xCC, 0x5D, 0x65, 0xB6, 0x92, 0x6C, 0x70, 0x48, 0x50,
38 0xFD, 0xED, 0xB9, 0xDA, 0x5E, 0x15, 0x46, 0x57, 0xA7, 0x8D, 0x9D, 0x84,
39 0x90, 0xD8, 0xAB, 0x00, 0x8C, 0xBC, 0xD3, 0x0A, 0xF7, 0xE4, 0x58, 0x05,
40 0xB8, 0xB3, 0x45, 0x06, 0xD0, 0x2C, 0x1E, 0x8F, 0xCA, 0x3F, 0x0F, 0x02,
41 0xC1, 0xAF, 0xBD, 0x03, 0x01, 0x13, 0x8A, 0x6B, 0x3A, 0x91, 0x11, 0x41,
42 0x4F, 0x67, 0xDC, 0xEA, 0x97, 0xF2, 0xCF, 0xCE, 0xF0, 0xB4, 0xE6, 0x73,
43 0x96, 0xAC, 0x74, 0x22, 0xE7, 0xAD, 0x35, 0x85, 0xE2, 0xF9, 0x37, 0xE8,
44 0x1C, 0x75, 0xDF, 0x6E, 0x47, 0xF1, 0x1A, 0x71, 0x1D, 0x29, 0xC5, 0x89,
45 0x6F, 0xB7, 0x62, 0x0E, 0xAA, 0x18, 0xBE, 0x1B, 0xFC, 0x56, 0x3E, 0x4B,
46 0xC6, 0xD2, 0x79, 0x20, 0x9A, 0xDB, 0xC0, 0xFE, 0x78, 0xCD, 0x5A, 0xF4,
47 0x1F, 0xDD, 0xA8, 0x33, 0x88, 0x07, 0xC7, 0x31, 0xB1, 0x12, 0x10, 0x59,
48 0x27, 0x80, 0xEC, 0x5F, 0x60, 0x51, 0x7F, 0xA9, 0x19, 0xB5, 0x4A, 0x0D,
49 0x2D, 0xE5, 0x7A, 0x9F, 0x93, 0xC9, 0x9C, 0xEF, 0xA0, 0xE0, 0x3B, 0x4D,
50 0xAE, 0x2A, 0xF5, 0xB0, 0xC8, 0xEB, 0xBB, 0x3C, 0x83, 0x53, 0x99, 0x61,
51 0x17, 0x2B, 0x04, 0x7E, 0xBA, 0x77, 0xD6, 0x26, 0xE1, 0x69, 0x14, 0x63,
52 0x55, 0x21, 0x0C, 0x7D
56 add_round_key(unsigned *state
, const uint32_t *skeys
)
60 for (i
= 0; i
< 16; i
+= 4) {
64 state
[i
+ 0] ^= (unsigned)(k
>> 24);
65 state
[i
+ 1] ^= (unsigned)(k
>> 16) & 0xFF;
66 state
[i
+ 2] ^= (unsigned)(k
>> 8) & 0xFF;
67 state
[i
+ 3] ^= (unsigned)k
& 0xFF;
72 inv_sub_bytes(unsigned *state
)
76 for (i
= 0; i
< 16; i
++) {
77 state
[i
] = iS
[state
[i
]];
82 inv_shift_rows(unsigned *state
)
101 state
[7] = state
[11];
102 state
[11] = state
[15];
106 static inline unsigned
112 return (x
^ y
^ (y
<< 1) ^ (y
<< 3) ^ (y
<< 4)) & 0xFF;
116 inv_mix_columns(unsigned *state
)
120 for (i
= 0; i
< 16; i
+= 4) {
121 unsigned s0
, s1
, s2
, s3
;
122 unsigned t0
, t1
, t2
, t3
;
128 t0
= (s0
<< 1) ^ (s0
<< 2) ^ (s0
<< 3)
129 ^ s1
^ (s1
<< 1) ^ (s1
<< 3)
130 ^ s2
^ (s2
<< 2) ^ (s2
<< 3)
133 ^ (s1
<< 1) ^ (s1
<< 2) ^ (s1
<< 3)
134 ^ s2
^ (s2
<< 1) ^ (s2
<< 3)
135 ^ s3
^ (s3
<< 2) ^ (s3
<< 3);
136 t2
= s0
^ (s0
<< 2) ^ (s0
<< 3)
138 ^ (s2
<< 1) ^ (s2
<< 2) ^ (s2
<< 3)
139 ^ s3
^ (s3
<< 1) ^ (s3
<< 3);
140 t3
= s0
^ (s0
<< 1) ^ (s0
<< 3)
141 ^ s1
^ (s1
<< 2) ^ (s1
<< 3)
143 ^ (s3
<< 1) ^ (s3
<< 2) ^ (s3
<< 3);
144 state
[i
+ 0] = gf256red(t0
);
145 state
[i
+ 1] = gf256red(t1
);
146 state
[i
+ 2] = gf256red(t2
);
147 state
[i
+ 3] = gf256red(t3
);
153 br_aes_small_decrypt(unsigned num_rounds
, const uint32_t *skey
, void *data
)
160 for (u
= 0; u
< 16; u
++) {
163 add_round_key(state
, skey
+ (num_rounds
<< 2));
164 for (u
= num_rounds
- 1; u
> 0; u
--) {
165 inv_shift_rows(state
);
166 inv_sub_bytes(state
);
167 add_round_key(state
, skey
+ (u
<< 2));
168 inv_mix_columns(state
);
170 inv_shift_rows(state
);
171 inv_sub_bytes(state
);
172 add_round_key(state
, skey
);
173 for (u
= 0; u
< 16; u
++) {