4 * AES Cipher Algorithm.
6 * Based on Brian Gladman's code.
9 * Alexander Kjeldaas <astor@fast.no>
10 * Herbert Valerio Riedel <hvr@hvrlab.org>
11 * Kyle McMartin <kyle@debian.org>
12 * Adam J. Richter <adam@yggdrasil.com> (conversion to 2.5 API).
13 * Andreas Steinmetz <ast@domdv.de> (adapted to x86_64 assembler)
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
20 * ---------------------------------------------------------------------------
21 * Copyright (c) 2002, Dr Brian Gladman <brg@gladman.me.uk>, Worcester, UK.
22 * All rights reserved.
26 * The free distribution and use of this software in both source and binary
27 * form is allowed (with or without changes) provided that:
29 * 1. distributions of this source code include the above copyright
30 * notice, this list of conditions and the following disclaimer;
32 * 2. distributions in binary form include the above copyright
33 * notice, this list of conditions and the following disclaimer
34 * in the documentation and/or other associated materials;
36 * 3. the copyright holder's name is not used to endorse products
37 * built using this software without specific written permission.
39 * ALTERNATIVELY, provided that this notice is retained in full, this product
40 * may be distributed under the terms of the GNU General Public License (GPL),
41 * in which case the provisions of the GPL apply INSTEAD OF those given above.
45 * This software is provided 'as is' with no explicit or implied warranties
46 * in respect of its properties, including, but not limited to, correctness
47 * and/or fitness for purpose.
48 * ---------------------------------------------------------------------------
51 /* Some changes from the Gladman version:
52 s/RIJNDAEL(e_key)/E_KEY/g
53 s/RIJNDAEL(d_key)/D_KEY/g
56 #include <asm/byteorder.h>
57 #include <crypto/aes.h>
58 #include <linux/bitops.h>
59 #include <linux/crypto.h>
60 #include <linux/errno.h>
61 #include <linux/init.h>
62 #include <linux/module.h>
63 #include <linux/types.h>
66 * #define byte(x, nr) ((unsigned char)((x) >> (nr*8)))
68 static inline u8 byte(const u32 x, const unsigned n)
79 #define E_KEY (&ctx->buf[0])
80 #define D_KEY (&ctx->buf[60])
82 static u8 pow_tab[256] __initdata;
83 static u8 log_tab[256] __initdata;
84 static u8 sbx_tab[256] __initdata;
85 static u8 isb_tab[256] __initdata;
86 static u32 rco_tab[10];
87 u32 aes_ft_tab[4][256];
88 u32 aes_it_tab[4][256];
90 u32 aes_fl_tab[4][256];
91 u32 aes_il_tab[4][256];
93 static inline u8 f_mult(u8 a, u8 b)
95 u8 aa = log_tab[a], cc = aa + log_tab[b];
97 return pow_tab[cc + (cc < aa ? 1 : 0)];
100 #define ff_mult(a, b) (a && b ? f_mult(a, b) : 0)
103 (aes_fl_tab[0][byte(x, 0)] ^ \
104 aes_fl_tab[1][byte(x, 1)] ^ \
105 aes_fl_tab[2][byte(x, 2)] ^ \
106 aes_fl_tab[3][byte(x, 3)])
108 static void __init gen_tabs(void)
113 /* log and power tables for GF(2**8) finite field with
114 0x011b as modular polynomial - the simplest primitive
115 root is 0x03, used here to generate the tables */
117 for (i = 0, p = 1; i < 256; ++i) {
121 p ^= (p << 1) ^ (p & 0x80 ? 0x01b : 0);
126 for (i = 0, p = 1; i < 10; ++i) {
129 p = (p << 1) ^ (p & 0x80 ? 0x01b : 0);
132 for (i = 0; i < 256; ++i) {
133 p = (i ? pow_tab[255 - log_tab[i]] : 0);
134 q = ((p >> 7) | (p << 1)) ^ ((p >> 6) | (p << 2));
135 p ^= 0x63 ^ q ^ ((q >> 6) | (q << 2));
140 for (i = 0; i < 256; ++i) {
144 aes_fl_tab[0][i] = t;
145 aes_fl_tab[1][i] = rol32(t, 8);
146 aes_fl_tab[2][i] = rol32(t, 16);
147 aes_fl_tab[3][i] = rol32(t, 24);
149 t = ((u32)ff_mult(2, p)) |
151 ((u32)p << 16) | ((u32)ff_mult(3, p) << 24);
153 aes_ft_tab[0][i] = t;
154 aes_ft_tab[1][i] = rol32(t, 8);
155 aes_ft_tab[2][i] = rol32(t, 16);
156 aes_ft_tab[3][i] = rol32(t, 24);
161 aes_il_tab[0][i] = t;
162 aes_il_tab[1][i] = rol32(t, 8);
163 aes_il_tab[2][i] = rol32(t, 16);
164 aes_il_tab[3][i] = rol32(t, 24);
166 t = ((u32)ff_mult(14, p)) |
167 ((u32)ff_mult(9, p) << 8) |
168 ((u32)ff_mult(13, p) << 16) |
169 ((u32)ff_mult(11, p) << 24);
171 aes_it_tab[0][i] = t;
172 aes_it_tab[1][i] = rol32(t, 8);
173 aes_it_tab[2][i] = rol32(t, 16);
174 aes_it_tab[3][i] = rol32(t, 24);
178 #define star_x(x) (((x) & 0x7f7f7f7f) << 1) ^ ((((x) & 0x80808080) >> 7) * 0x1b)
180 #define imix_col(y, x) \
186 (y) ^= ror32(u ^ t, 8) ^ \
190 /* initialise the key schedule from the user supplied key */
194 t = ror32(t, 8); t = ls_box(t) ^ rco_tab[i]; \
195 t ^= E_KEY[4 * i]; E_KEY[4 * i + 4] = t; \
196 t ^= E_KEY[4 * i + 1]; E_KEY[4 * i + 5] = t; \
197 t ^= E_KEY[4 * i + 2]; E_KEY[4 * i + 6] = t; \
198 t ^= E_KEY[4 * i + 3]; E_KEY[4 * i + 7] = t; \
203 t = ror32(t, 8); t = ls_box(t) ^ rco_tab[i]; \
204 t ^= E_KEY[6 * i]; E_KEY[6 * i + 6] = t; \
205 t ^= E_KEY[6 * i + 1]; E_KEY[6 * i + 7] = t; \
206 t ^= E_KEY[6 * i + 2]; E_KEY[6 * i + 8] = t; \
207 t ^= E_KEY[6 * i + 3]; E_KEY[6 * i + 9] = t; \
208 t ^= E_KEY[6 * i + 4]; E_KEY[6 * i + 10] = t; \
209 t ^= E_KEY[6 * i + 5]; E_KEY[6 * i + 11] = t; \
214 t = ror32(t, 8); ; t = ls_box(t) ^ rco_tab[i]; \
215 t ^= E_KEY[8 * i]; E_KEY[8 * i + 8] = t; \
216 t ^= E_KEY[8 * i + 1]; E_KEY[8 * i + 9] = t; \
217 t ^= E_KEY[8 * i + 2]; E_KEY[8 * i + 10] = t; \
218 t ^= E_KEY[8 * i + 3]; E_KEY[8 * i + 11] = t; \
219 t = E_KEY[8 * i + 4] ^ ls_box(t); \
220 E_KEY[8 * i + 12] = t; \
221 t ^= E_KEY[8 * i + 5]; E_KEY[8 * i + 13] = t; \
222 t ^= E_KEY[8 * i + 6]; E_KEY[8 * i + 14] = t; \
223 t ^= E_KEY[8 * i + 7]; E_KEY[8 * i + 15] = t; \
226 static int aes_set_key(struct crypto_tfm *tfm, const u8 *in_key,
227 unsigned int key_len)
229 struct aes_ctx *ctx = crypto_tfm_ctx(tfm);
230 const __le32 *key = (const __le32 *)in_key;
231 u32 *flags = &tfm->crt_flags;
232 u32 i, j, t, u, v, w;
235 *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
239 ctx->key_length = key_len;
241 D_KEY[key_len + 24] = E_KEY[0] = le32_to_cpu(key[0]);
242 D_KEY[key_len + 25] = E_KEY[1] = le32_to_cpu(key[1]);
243 D_KEY[key_len + 26] = E_KEY[2] = le32_to_cpu(key[2]);
244 D_KEY[key_len + 27] = E_KEY[3] = le32_to_cpu(key[3]);
249 for (i = 0; i < 10; ++i)
254 E_KEY[4] = le32_to_cpu(key[4]);
255 t = E_KEY[5] = le32_to_cpu(key[5]);
256 for (i = 0; i < 8; ++i)
261 E_KEY[4] = le32_to_cpu(key[4]);
262 E_KEY[5] = le32_to_cpu(key[5]);
263 E_KEY[6] = le32_to_cpu(key[6]);
264 t = E_KEY[7] = le32_to_cpu(key[7]);
265 for (i = 0; i < 7; ++i)
270 D_KEY[0] = E_KEY[key_len + 24];
271 D_KEY[1] = E_KEY[key_len + 25];
272 D_KEY[2] = E_KEY[key_len + 26];
273 D_KEY[3] = E_KEY[key_len + 27];
275 for (i = 4; i < key_len + 24; ++i) {
276 j = key_len + 24 - (i & ~3) + (i & 3);
277 imix_col(D_KEY[j], E_KEY[i]);
283 asmlinkage void aes_enc_blk(struct crypto_tfm *tfm, u8 *out, const u8 *in);
284 asmlinkage void aes_dec_blk(struct crypto_tfm *tfm, u8 *out, const u8 *in);
286 static void aes_encrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
288 aes_enc_blk(tfm, dst, src);
291 static void aes_decrypt(struct crypto_tfm *tfm, u8 *dst, const u8 *src)
293 aes_dec_blk(tfm, dst, src);
296 static struct crypto_alg aes_alg = {
298 .cra_driver_name = "aes-x86_64",
300 .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
301 .cra_blocksize = AES_BLOCK_SIZE,
302 .cra_ctxsize = sizeof(struct aes_ctx),
303 .cra_module = THIS_MODULE,
304 .cra_list = LIST_HEAD_INIT(aes_alg.cra_list),
307 .cia_min_keysize = AES_MIN_KEY_SIZE,
308 .cia_max_keysize = AES_MAX_KEY_SIZE,
309 .cia_setkey = aes_set_key,
310 .cia_encrypt = aes_encrypt,
311 .cia_decrypt = aes_decrypt
316 static int __init aes_init(void)
319 return crypto_register_alg(&aes_alg);
322 static void __exit aes_fini(void)
324 crypto_unregister_alg(&aes_alg);
327 module_init(aes_init);
328 module_exit(aes_fini);
330 MODULE_DESCRIPTION("Rijndael (AES) Cipher Algorithm");
331 MODULE_LICENSE("GPL");