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11#include <asm/hwcap.h>
12#include <asm/neon.h>
13#include <asm/hwcap.h>
14#include <crypto/aes.h>
15#include <crypto/ablk_helper.h>
16#include <crypto/algapi.h>
17#include <linux/module.h>
18#include <crypto/xts.h>
19
20MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions");
21MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
22MODULE_LICENSE("GPL v2");
23
24
25asmlinkage u32 ce_aes_sub(u32 input);
26asmlinkage void ce_aes_invert(void *dst, void *src);
27
28asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u8 const rk[],
29 int rounds, int blocks);
30asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u8 const rk[],
31 int rounds, int blocks);
32
33asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u8 const rk[],
34 int rounds, int blocks, u8 iv[]);
35asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u8 const rk[],
36 int rounds, int blocks, u8 iv[]);
37
38asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u8 const rk[],
39 int rounds, int blocks, u8 ctr[]);
40
41asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u8 const rk1[],
42 int rounds, int blocks, u8 iv[],
43 u8 const rk2[], int first);
44asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u8 const rk1[],
45 int rounds, int blocks, u8 iv[],
46 u8 const rk2[], int first);
47
48struct aes_block {
49 u8 b[AES_BLOCK_SIZE];
50};
51
52static int num_rounds(struct crypto_aes_ctx *ctx)
53{
54
55
56
57
58
59
60
61 return 6 + ctx->key_length / 4;
62}
63
64static int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
65 unsigned int key_len)
66{
67
68
69
70 static u8 const rcon[] = {
71 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
72 };
73
74 u32 kwords = key_len / sizeof(u32);
75 struct aes_block *key_enc, *key_dec;
76 int i, j;
77
78 if (key_len != AES_KEYSIZE_128 &&
79 key_len != AES_KEYSIZE_192 &&
80 key_len != AES_KEYSIZE_256)
81 return -EINVAL;
82
83 memcpy(ctx->key_enc, in_key, key_len);
84 ctx->key_length = key_len;
85
86 kernel_neon_begin();
87 for (i = 0; i < sizeof(rcon); i++) {
88 u32 *rki = ctx->key_enc + (i * kwords);
89 u32 *rko = rki + kwords;
90
91 rko[0] = ror32(ce_aes_sub(rki[kwords - 1]), 8);
92 rko[0] = rko[0] ^ rki[0] ^ rcon[i];
93 rko[1] = rko[0] ^ rki[1];
94 rko[2] = rko[1] ^ rki[2];
95 rko[3] = rko[2] ^ rki[3];
96
97 if (key_len == AES_KEYSIZE_192) {
98 if (i >= 7)
99 break;
100 rko[4] = rko[3] ^ rki[4];
101 rko[5] = rko[4] ^ rki[5];
102 } else if (key_len == AES_KEYSIZE_256) {
103 if (i >= 6)
104 break;
105 rko[4] = ce_aes_sub(rko[3]) ^ rki[4];
106 rko[5] = rko[4] ^ rki[5];
107 rko[6] = rko[5] ^ rki[6];
108 rko[7] = rko[6] ^ rki[7];
109 }
110 }
111
112
113
114
115
116
117
118 key_enc = (struct aes_block *)ctx->key_enc;
119 key_dec = (struct aes_block *)ctx->key_dec;
120 j = num_rounds(ctx);
121
122 key_dec[0] = key_enc[j];
123 for (i = 1, j--; j > 0; i++, j--)
124 ce_aes_invert(key_dec + i, key_enc + j);
125 key_dec[i] = key_enc[0];
126
127 kernel_neon_end();
128 return 0;
129}
130
131static int ce_aes_setkey(struct crypto_tfm *tfm, const u8 *in_key,
132 unsigned int key_len)
133{
134 struct crypto_aes_ctx *ctx = crypto_tfm_ctx(tfm);
135 int ret;
136
137 ret = ce_aes_expandkey(ctx, in_key, key_len);
138 if (!ret)
139 return 0;
140
141 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
142 return -EINVAL;
143}
144
145struct crypto_aes_xts_ctx {
146 struct crypto_aes_ctx key1;
147 struct crypto_aes_ctx __aligned(8) key2;
148};
149
150static int xts_set_key(struct crypto_tfm *tfm, const u8 *in_key,
151 unsigned int key_len)
152{
153 struct crypto_aes_xts_ctx *ctx = crypto_tfm_ctx(tfm);
154 int ret;
155
156 ret = xts_check_key(tfm, in_key, key_len);
157 if (ret)
158 return ret;
159
160 ret = ce_aes_expandkey(&ctx->key1, in_key, key_len / 2);
161 if (!ret)
162 ret = ce_aes_expandkey(&ctx->key2, &in_key[key_len / 2],
163 key_len / 2);
164 if (!ret)
165 return 0;
166
167 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
168 return -EINVAL;
169}
170
171static int ecb_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
172 struct scatterlist *src, unsigned int nbytes)
173{
174 struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
175 struct blkcipher_walk walk;
176 unsigned int blocks;
177 int err;
178
179 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
180 blkcipher_walk_init(&walk, dst, src, nbytes);
181 err = blkcipher_walk_virt(desc, &walk);
182
183 kernel_neon_begin();
184 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
185 ce_aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
186 (u8 *)ctx->key_enc, num_rounds(ctx), blocks);
187 err = blkcipher_walk_done(desc, &walk,
188 walk.nbytes % AES_BLOCK_SIZE);
189 }
190 kernel_neon_end();
191 return err;
192}
193
194static int ecb_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
195 struct scatterlist *src, unsigned int nbytes)
196{
197 struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
198 struct blkcipher_walk walk;
199 unsigned int blocks;
200 int err;
201
202 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
203 blkcipher_walk_init(&walk, dst, src, nbytes);
204 err = blkcipher_walk_virt(desc, &walk);
205
206 kernel_neon_begin();
207 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
208 ce_aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
209 (u8 *)ctx->key_dec, num_rounds(ctx), blocks);
210 err = blkcipher_walk_done(desc, &walk,
211 walk.nbytes % AES_BLOCK_SIZE);
212 }
213 kernel_neon_end();
214 return err;
215}
216
217static int cbc_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
218 struct scatterlist *src, unsigned int nbytes)
219{
220 struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
221 struct blkcipher_walk walk;
222 unsigned int blocks;
223 int err;
224
225 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
226 blkcipher_walk_init(&walk, dst, src, nbytes);
227 err = blkcipher_walk_virt(desc, &walk);
228
229 kernel_neon_begin();
230 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
231 ce_aes_cbc_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
232 (u8 *)ctx->key_enc, num_rounds(ctx), blocks,
233 walk.iv);
234 err = blkcipher_walk_done(desc, &walk,
235 walk.nbytes % AES_BLOCK_SIZE);
236 }
237 kernel_neon_end();
238 return err;
239}
240
241static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
242 struct scatterlist *src, unsigned int nbytes)
243{
244 struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
245 struct blkcipher_walk walk;
246 unsigned int blocks;
247 int err;
248
249 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
250 blkcipher_walk_init(&walk, dst, src, nbytes);
251 err = blkcipher_walk_virt(desc, &walk);
252
253 kernel_neon_begin();
254 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
255 ce_aes_cbc_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
256 (u8 *)ctx->key_dec, num_rounds(ctx), blocks,
257 walk.iv);
258 err = blkcipher_walk_done(desc, &walk,
259 walk.nbytes % AES_BLOCK_SIZE);
260 }
261 kernel_neon_end();
262 return err;
263}
264
265static int ctr_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
266 struct scatterlist *src, unsigned int nbytes)
267{
268 struct crypto_aes_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
269 struct blkcipher_walk walk;
270 int err, blocks;
271
272 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
273 blkcipher_walk_init(&walk, dst, src, nbytes);
274 err = blkcipher_walk_virt_block(desc, &walk, AES_BLOCK_SIZE);
275
276 kernel_neon_begin();
277 while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
278 ce_aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
279 (u8 *)ctx->key_enc, num_rounds(ctx), blocks,
280 walk.iv);
281 nbytes -= blocks * AES_BLOCK_SIZE;
282 if (nbytes && nbytes == walk.nbytes % AES_BLOCK_SIZE)
283 break;
284 err = blkcipher_walk_done(desc, &walk,
285 walk.nbytes % AES_BLOCK_SIZE);
286 }
287 if (walk.nbytes % AES_BLOCK_SIZE) {
288 u8 *tdst = walk.dst.virt.addr + blocks * AES_BLOCK_SIZE;
289 u8 *tsrc = walk.src.virt.addr + blocks * AES_BLOCK_SIZE;
290 u8 __aligned(8) tail[AES_BLOCK_SIZE];
291
292
293
294
295
296 blocks = (nbytes <= 8) ? -1 : 1;
297
298 ce_aes_ctr_encrypt(tail, tsrc, (u8 *)ctx->key_enc,
299 num_rounds(ctx), blocks, walk.iv);
300 memcpy(tdst, tail, nbytes);
301 err = blkcipher_walk_done(desc, &walk, 0);
302 }
303 kernel_neon_end();
304
305 return err;
306}
307
308static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
309 struct scatterlist *src, unsigned int nbytes)
310{
311 struct crypto_aes_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
312 int err, first, rounds = num_rounds(&ctx->key1);
313 struct blkcipher_walk walk;
314 unsigned int blocks;
315
316 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
317 blkcipher_walk_init(&walk, dst, src, nbytes);
318 err = blkcipher_walk_virt(desc, &walk);
319
320 kernel_neon_begin();
321 for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
322 ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
323 (u8 *)ctx->key1.key_enc, rounds, blocks,
324 walk.iv, (u8 *)ctx->key2.key_enc, first);
325 err = blkcipher_walk_done(desc, &walk,
326 walk.nbytes % AES_BLOCK_SIZE);
327 }
328 kernel_neon_end();
329
330 return err;
331}
332
333static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst,
334 struct scatterlist *src, unsigned int nbytes)
335{
336 struct crypto_aes_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm);
337 int err, first, rounds = num_rounds(&ctx->key1);
338 struct blkcipher_walk walk;
339 unsigned int blocks;
340
341 desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
342 blkcipher_walk_init(&walk, dst, src, nbytes);
343 err = blkcipher_walk_virt(desc, &walk);
344
345 kernel_neon_begin();
346 for (first = 1; (blocks = (walk.nbytes / AES_BLOCK_SIZE)); first = 0) {
347 ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
348 (u8 *)ctx->key1.key_dec, rounds, blocks,
349 walk.iv, (u8 *)ctx->key2.key_enc, first);
350 err = blkcipher_walk_done(desc, &walk,
351 walk.nbytes % AES_BLOCK_SIZE);
352 }
353 kernel_neon_end();
354
355 return err;
356}
357
358static struct crypto_alg aes_algs[] = { {
359 .cra_name = "__ecb-aes-ce",
360 .cra_driver_name = "__driver-ecb-aes-ce",
361 .cra_priority = 0,
362 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
363 CRYPTO_ALG_INTERNAL,
364 .cra_blocksize = AES_BLOCK_SIZE,
365 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
366 .cra_alignmask = 7,
367 .cra_type = &crypto_blkcipher_type,
368 .cra_module = THIS_MODULE,
369 .cra_blkcipher = {
370 .min_keysize = AES_MIN_KEY_SIZE,
371 .max_keysize = AES_MAX_KEY_SIZE,
372 .ivsize = 0,
373 .setkey = ce_aes_setkey,
374 .encrypt = ecb_encrypt,
375 .decrypt = ecb_decrypt,
376 },
377}, {
378 .cra_name = "__cbc-aes-ce",
379 .cra_driver_name = "__driver-cbc-aes-ce",
380 .cra_priority = 0,
381 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
382 CRYPTO_ALG_INTERNAL,
383 .cra_blocksize = AES_BLOCK_SIZE,
384 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
385 .cra_alignmask = 7,
386 .cra_type = &crypto_blkcipher_type,
387 .cra_module = THIS_MODULE,
388 .cra_blkcipher = {
389 .min_keysize = AES_MIN_KEY_SIZE,
390 .max_keysize = AES_MAX_KEY_SIZE,
391 .ivsize = AES_BLOCK_SIZE,
392 .setkey = ce_aes_setkey,
393 .encrypt = cbc_encrypt,
394 .decrypt = cbc_decrypt,
395 },
396}, {
397 .cra_name = "__ctr-aes-ce",
398 .cra_driver_name = "__driver-ctr-aes-ce",
399 .cra_priority = 0,
400 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
401 CRYPTO_ALG_INTERNAL,
402 .cra_blocksize = 1,
403 .cra_ctxsize = sizeof(struct crypto_aes_ctx),
404 .cra_alignmask = 7,
405 .cra_type = &crypto_blkcipher_type,
406 .cra_module = THIS_MODULE,
407 .cra_blkcipher = {
408 .min_keysize = AES_MIN_KEY_SIZE,
409 .max_keysize = AES_MAX_KEY_SIZE,
410 .ivsize = AES_BLOCK_SIZE,
411 .setkey = ce_aes_setkey,
412 .encrypt = ctr_encrypt,
413 .decrypt = ctr_encrypt,
414 },
415}, {
416 .cra_name = "__xts-aes-ce",
417 .cra_driver_name = "__driver-xts-aes-ce",
418 .cra_priority = 0,
419 .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER |
420 CRYPTO_ALG_INTERNAL,
421 .cra_blocksize = AES_BLOCK_SIZE,
422 .cra_ctxsize = sizeof(struct crypto_aes_xts_ctx),
423 .cra_alignmask = 7,
424 .cra_type = &crypto_blkcipher_type,
425 .cra_module = THIS_MODULE,
426 .cra_blkcipher = {
427 .min_keysize = 2 * AES_MIN_KEY_SIZE,
428 .max_keysize = 2 * AES_MAX_KEY_SIZE,
429 .ivsize = AES_BLOCK_SIZE,
430 .setkey = xts_set_key,
431 .encrypt = xts_encrypt,
432 .decrypt = xts_decrypt,
433 },
434}, {
435 .cra_name = "ecb(aes)",
436 .cra_driver_name = "ecb-aes-ce",
437 .cra_priority = 300,
438 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
439 .cra_blocksize = AES_BLOCK_SIZE,
440 .cra_ctxsize = sizeof(struct async_helper_ctx),
441 .cra_alignmask = 7,
442 .cra_type = &crypto_ablkcipher_type,
443 .cra_module = THIS_MODULE,
444 .cra_init = ablk_init,
445 .cra_exit = ablk_exit,
446 .cra_ablkcipher = {
447 .min_keysize = AES_MIN_KEY_SIZE,
448 .max_keysize = AES_MAX_KEY_SIZE,
449 .ivsize = 0,
450 .setkey = ablk_set_key,
451 .encrypt = ablk_encrypt,
452 .decrypt = ablk_decrypt,
453 }
454}, {
455 .cra_name = "cbc(aes)",
456 .cra_driver_name = "cbc-aes-ce",
457 .cra_priority = 300,
458 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
459 .cra_blocksize = AES_BLOCK_SIZE,
460 .cra_ctxsize = sizeof(struct async_helper_ctx),
461 .cra_alignmask = 7,
462 .cra_type = &crypto_ablkcipher_type,
463 .cra_module = THIS_MODULE,
464 .cra_init = ablk_init,
465 .cra_exit = ablk_exit,
466 .cra_ablkcipher = {
467 .min_keysize = AES_MIN_KEY_SIZE,
468 .max_keysize = AES_MAX_KEY_SIZE,
469 .ivsize = AES_BLOCK_SIZE,
470 .setkey = ablk_set_key,
471 .encrypt = ablk_encrypt,
472 .decrypt = ablk_decrypt,
473 }
474}, {
475 .cra_name = "ctr(aes)",
476 .cra_driver_name = "ctr-aes-ce",
477 .cra_priority = 300,
478 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
479 .cra_blocksize = 1,
480 .cra_ctxsize = sizeof(struct async_helper_ctx),
481 .cra_alignmask = 7,
482 .cra_type = &crypto_ablkcipher_type,
483 .cra_module = THIS_MODULE,
484 .cra_init = ablk_init,
485 .cra_exit = ablk_exit,
486 .cra_ablkcipher = {
487 .min_keysize = AES_MIN_KEY_SIZE,
488 .max_keysize = AES_MAX_KEY_SIZE,
489 .ivsize = AES_BLOCK_SIZE,
490 .setkey = ablk_set_key,
491 .encrypt = ablk_encrypt,
492 .decrypt = ablk_decrypt,
493 }
494}, {
495 .cra_name = "xts(aes)",
496 .cra_driver_name = "xts-aes-ce",
497 .cra_priority = 300,
498 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER|CRYPTO_ALG_ASYNC,
499 .cra_blocksize = AES_BLOCK_SIZE,
500 .cra_ctxsize = sizeof(struct async_helper_ctx),
501 .cra_alignmask = 7,
502 .cra_type = &crypto_ablkcipher_type,
503 .cra_module = THIS_MODULE,
504 .cra_init = ablk_init,
505 .cra_exit = ablk_exit,
506 .cra_ablkcipher = {
507 .min_keysize = 2 * AES_MIN_KEY_SIZE,
508 .max_keysize = 2 * AES_MAX_KEY_SIZE,
509 .ivsize = AES_BLOCK_SIZE,
510 .setkey = ablk_set_key,
511 .encrypt = ablk_encrypt,
512 .decrypt = ablk_decrypt,
513 }
514} };
515
516static int __init aes_init(void)
517{
518 if (!(elf_hwcap2 & HWCAP2_AES))
519 return -ENODEV;
520 return crypto_register_algs(aes_algs, ARRAY_SIZE(aes_algs));
521}
522
523static void __exit aes_exit(void)
524{
525 crypto_unregister_algs(aes_algs, ARRAY_SIZE(aes_algs));
526}
527
528module_init(aes_init);
529module_exit(aes_exit);
530
