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