xref: /linux/arch/arm/crypto/aes-ce-glue.c (revision 7ec462100ef9142344ddbf86f2c3008b97acddbe)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * aes-ce-glue.c - wrapper code for ARMv8 AES
4  *
5  * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@linaro.org>
6  */
7 
8 #include <asm/hwcap.h>
9 #include <asm/neon.h>
10 #include <asm/simd.h>
11 #include <linux/unaligned.h>
12 #include <crypto/aes.h>
13 #include <crypto/ctr.h>
14 #include <crypto/internal/simd.h>
15 #include <crypto/internal/skcipher.h>
16 #include <crypto/scatterwalk.h>
17 #include <linux/cpufeature.h>
18 #include <linux/module.h>
19 #include <crypto/xts.h>
20 
21 MODULE_DESCRIPTION("AES-ECB/CBC/CTR/XTS using ARMv8 Crypto Extensions");
22 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
23 MODULE_LICENSE("GPL v2");
24 
25 /* defined in aes-ce-core.S */
26 asmlinkage u32 ce_aes_sub(u32 input);
27 asmlinkage void ce_aes_invert(void *dst, void *src);
28 
29 asmlinkage void ce_aes_ecb_encrypt(u8 out[], u8 const in[], u32 const rk[],
30 				   int rounds, int blocks);
31 asmlinkage void ce_aes_ecb_decrypt(u8 out[], u8 const in[], u32 const rk[],
32 				   int rounds, int blocks);
33 
34 asmlinkage void ce_aes_cbc_encrypt(u8 out[], u8 const in[], u32 const rk[],
35 				   int rounds, int blocks, u8 iv[]);
36 asmlinkage void ce_aes_cbc_decrypt(u8 out[], u8 const in[], u32 const rk[],
37 				   int rounds, int blocks, u8 iv[]);
38 asmlinkage void ce_aes_cbc_cts_encrypt(u8 out[], u8 const in[], u32 const rk[],
39 				   int rounds, int bytes, u8 const iv[]);
40 asmlinkage void ce_aes_cbc_cts_decrypt(u8 out[], u8 const in[], u32 const rk[],
41 				   int rounds, int bytes, u8 const iv[]);
42 
43 asmlinkage void ce_aes_ctr_encrypt(u8 out[], u8 const in[], u32 const rk[],
44 				   int rounds, int blocks, u8 ctr[]);
45 
46 asmlinkage void ce_aes_xts_encrypt(u8 out[], u8 const in[], u32 const rk1[],
47 				   int rounds, int bytes, u8 iv[],
48 				   u32 const rk2[], int first);
49 asmlinkage void ce_aes_xts_decrypt(u8 out[], u8 const in[], u32 const rk1[],
50 				   int rounds, int bytes, u8 iv[],
51 				   u32 const rk2[], int first);
52 
53 struct aes_block {
54 	u8 b[AES_BLOCK_SIZE];
55 };
56 
num_rounds(struct crypto_aes_ctx * ctx)57 static int num_rounds(struct crypto_aes_ctx *ctx)
58 {
59 	/*
60 	 * # of rounds specified by AES:
61 	 * 128 bit key		10 rounds
62 	 * 192 bit key		12 rounds
63 	 * 256 bit key		14 rounds
64 	 * => n byte key	=> 6 + (n/4) rounds
65 	 */
66 	return 6 + ctx->key_length / 4;
67 }
68 
ce_aes_expandkey(struct crypto_aes_ctx * ctx,const u8 * in_key,unsigned int key_len)69 static int ce_aes_expandkey(struct crypto_aes_ctx *ctx, const u8 *in_key,
70 			    unsigned int key_len)
71 {
72 	/*
73 	 * The AES key schedule round constants
74 	 */
75 	static u8 const rcon[] = {
76 		0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36,
77 	};
78 
79 	u32 kwords = key_len / sizeof(u32);
80 	struct aes_block *key_enc, *key_dec;
81 	int i, j;
82 
83 	if (key_len != AES_KEYSIZE_128 &&
84 	    key_len != AES_KEYSIZE_192 &&
85 	    key_len != AES_KEYSIZE_256)
86 		return -EINVAL;
87 
88 	ctx->key_length = key_len;
89 	for (i = 0; i < kwords; i++)
90 		ctx->key_enc[i] = get_unaligned_le32(in_key + i * sizeof(u32));
91 
92 	kernel_neon_begin();
93 	for (i = 0; i < sizeof(rcon); i++) {
94 		u32 *rki = ctx->key_enc + (i * kwords);
95 		u32 *rko = rki + kwords;
96 
97 		rko[0] = ror32(ce_aes_sub(rki[kwords - 1]), 8);
98 		rko[0] = rko[0] ^ rki[0] ^ rcon[i];
99 		rko[1] = rko[0] ^ rki[1];
100 		rko[2] = rko[1] ^ rki[2];
101 		rko[3] = rko[2] ^ rki[3];
102 
103 		if (key_len == AES_KEYSIZE_192) {
104 			if (i >= 7)
105 				break;
106 			rko[4] = rko[3] ^ rki[4];
107 			rko[5] = rko[4] ^ rki[5];
108 		} else if (key_len == AES_KEYSIZE_256) {
109 			if (i >= 6)
110 				break;
111 			rko[4] = ce_aes_sub(rko[3]) ^ rki[4];
112 			rko[5] = rko[4] ^ rki[5];
113 			rko[6] = rko[5] ^ rki[6];
114 			rko[7] = rko[6] ^ rki[7];
115 		}
116 	}
117 
118 	/*
119 	 * Generate the decryption keys for the Equivalent Inverse Cipher.
120 	 * This involves reversing the order of the round keys, and applying
121 	 * the Inverse Mix Columns transformation on all but the first and
122 	 * the last one.
123 	 */
124 	key_enc = (struct aes_block *)ctx->key_enc;
125 	key_dec = (struct aes_block *)ctx->key_dec;
126 	j = num_rounds(ctx);
127 
128 	key_dec[0] = key_enc[j];
129 	for (i = 1, j--; j > 0; i++, j--)
130 		ce_aes_invert(key_dec + i, key_enc + j);
131 	key_dec[i] = key_enc[0];
132 
133 	kernel_neon_end();
134 	return 0;
135 }
136 
ce_aes_setkey(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)137 static int ce_aes_setkey(struct crypto_skcipher *tfm, const u8 *in_key,
138 			 unsigned int key_len)
139 {
140 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
141 
142 	return ce_aes_expandkey(ctx, in_key, key_len);
143 }
144 
145 struct crypto_aes_xts_ctx {
146 	struct crypto_aes_ctx key1;
147 	struct crypto_aes_ctx __aligned(8) key2;
148 };
149 
xts_set_key(struct crypto_skcipher * tfm,const u8 * in_key,unsigned int key_len)150 static int xts_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
151 		       unsigned int key_len)
152 {
153 	struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
154 	int ret;
155 
156 	ret = xts_verify_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 	return ret;
165 }
166 
ecb_encrypt(struct skcipher_request * req)167 static int ecb_encrypt(struct skcipher_request *req)
168 {
169 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
170 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
171 	struct skcipher_walk walk;
172 	unsigned int blocks;
173 	int err;
174 
175 	err = skcipher_walk_virt(&walk, req, false);
176 
177 	while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
178 		kernel_neon_begin();
179 		ce_aes_ecb_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
180 				   ctx->key_enc, num_rounds(ctx), blocks);
181 		kernel_neon_end();
182 		err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
183 	}
184 	return err;
185 }
186 
ecb_decrypt(struct skcipher_request * req)187 static int ecb_decrypt(struct skcipher_request *req)
188 {
189 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
190 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
191 	struct skcipher_walk walk;
192 	unsigned int blocks;
193 	int err;
194 
195 	err = skcipher_walk_virt(&walk, req, false);
196 
197 	while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
198 		kernel_neon_begin();
199 		ce_aes_ecb_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
200 				   ctx->key_dec, num_rounds(ctx), blocks);
201 		kernel_neon_end();
202 		err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
203 	}
204 	return err;
205 }
206 
cbc_encrypt_walk(struct skcipher_request * req,struct skcipher_walk * walk)207 static int cbc_encrypt_walk(struct skcipher_request *req,
208 			    struct skcipher_walk *walk)
209 {
210 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
211 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
212 	unsigned int blocks;
213 	int err = 0;
214 
215 	while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) {
216 		kernel_neon_begin();
217 		ce_aes_cbc_encrypt(walk->dst.virt.addr, walk->src.virt.addr,
218 				   ctx->key_enc, num_rounds(ctx), blocks,
219 				   walk->iv);
220 		kernel_neon_end();
221 		err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE);
222 	}
223 	return err;
224 }
225 
cbc_encrypt(struct skcipher_request * req)226 static int cbc_encrypt(struct skcipher_request *req)
227 {
228 	struct skcipher_walk walk;
229 	int err;
230 
231 	err = skcipher_walk_virt(&walk, req, false);
232 	if (err)
233 		return err;
234 	return cbc_encrypt_walk(req, &walk);
235 }
236 
cbc_decrypt_walk(struct skcipher_request * req,struct skcipher_walk * walk)237 static int cbc_decrypt_walk(struct skcipher_request *req,
238 			    struct skcipher_walk *walk)
239 {
240 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
241 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
242 	unsigned int blocks;
243 	int err = 0;
244 
245 	while ((blocks = (walk->nbytes / AES_BLOCK_SIZE))) {
246 		kernel_neon_begin();
247 		ce_aes_cbc_decrypt(walk->dst.virt.addr, walk->src.virt.addr,
248 				   ctx->key_dec, num_rounds(ctx), blocks,
249 				   walk->iv);
250 		kernel_neon_end();
251 		err = skcipher_walk_done(walk, walk->nbytes % AES_BLOCK_SIZE);
252 	}
253 	return err;
254 }
255 
cbc_decrypt(struct skcipher_request * req)256 static int cbc_decrypt(struct skcipher_request *req)
257 {
258 	struct skcipher_walk walk;
259 	int err;
260 
261 	err = skcipher_walk_virt(&walk, req, false);
262 	if (err)
263 		return err;
264 	return cbc_decrypt_walk(req, &walk);
265 }
266 
cts_cbc_encrypt(struct skcipher_request * req)267 static int cts_cbc_encrypt(struct skcipher_request *req)
268 {
269 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
270 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
271 	int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2;
272 	struct scatterlist *src = req->src, *dst = req->dst;
273 	struct scatterlist sg_src[2], sg_dst[2];
274 	struct skcipher_request subreq;
275 	struct skcipher_walk walk;
276 	int err;
277 
278 	skcipher_request_set_tfm(&subreq, tfm);
279 	skcipher_request_set_callback(&subreq, skcipher_request_flags(req),
280 				      NULL, NULL);
281 
282 	if (req->cryptlen <= AES_BLOCK_SIZE) {
283 		if (req->cryptlen < AES_BLOCK_SIZE)
284 			return -EINVAL;
285 		cbc_blocks = 1;
286 	}
287 
288 	if (cbc_blocks > 0) {
289 		skcipher_request_set_crypt(&subreq, req->src, req->dst,
290 					   cbc_blocks * AES_BLOCK_SIZE,
291 					   req->iv);
292 
293 		err = skcipher_walk_virt(&walk, &subreq, false) ?:
294 		      cbc_encrypt_walk(&subreq, &walk);
295 		if (err)
296 			return err;
297 
298 		if (req->cryptlen == AES_BLOCK_SIZE)
299 			return 0;
300 
301 		dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen);
302 		if (req->dst != req->src)
303 			dst = scatterwalk_ffwd(sg_dst, req->dst,
304 					       subreq.cryptlen);
305 	}
306 
307 	/* handle ciphertext stealing */
308 	skcipher_request_set_crypt(&subreq, src, dst,
309 				   req->cryptlen - cbc_blocks * AES_BLOCK_SIZE,
310 				   req->iv);
311 
312 	err = skcipher_walk_virt(&walk, &subreq, false);
313 	if (err)
314 		return err;
315 
316 	kernel_neon_begin();
317 	ce_aes_cbc_cts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
318 			       ctx->key_enc, num_rounds(ctx), walk.nbytes,
319 			       walk.iv);
320 	kernel_neon_end();
321 
322 	return skcipher_walk_done(&walk, 0);
323 }
324 
cts_cbc_decrypt(struct skcipher_request * req)325 static int cts_cbc_decrypt(struct skcipher_request *req)
326 {
327 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
328 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
329 	int cbc_blocks = DIV_ROUND_UP(req->cryptlen, AES_BLOCK_SIZE) - 2;
330 	struct scatterlist *src = req->src, *dst = req->dst;
331 	struct scatterlist sg_src[2], sg_dst[2];
332 	struct skcipher_request subreq;
333 	struct skcipher_walk walk;
334 	int err;
335 
336 	skcipher_request_set_tfm(&subreq, tfm);
337 	skcipher_request_set_callback(&subreq, skcipher_request_flags(req),
338 				      NULL, NULL);
339 
340 	if (req->cryptlen <= AES_BLOCK_SIZE) {
341 		if (req->cryptlen < AES_BLOCK_SIZE)
342 			return -EINVAL;
343 		cbc_blocks = 1;
344 	}
345 
346 	if (cbc_blocks > 0) {
347 		skcipher_request_set_crypt(&subreq, req->src, req->dst,
348 					   cbc_blocks * AES_BLOCK_SIZE,
349 					   req->iv);
350 
351 		err = skcipher_walk_virt(&walk, &subreq, false) ?:
352 		      cbc_decrypt_walk(&subreq, &walk);
353 		if (err)
354 			return err;
355 
356 		if (req->cryptlen == AES_BLOCK_SIZE)
357 			return 0;
358 
359 		dst = src = scatterwalk_ffwd(sg_src, req->src, subreq.cryptlen);
360 		if (req->dst != req->src)
361 			dst = scatterwalk_ffwd(sg_dst, req->dst,
362 					       subreq.cryptlen);
363 	}
364 
365 	/* handle ciphertext stealing */
366 	skcipher_request_set_crypt(&subreq, src, dst,
367 				   req->cryptlen - cbc_blocks * AES_BLOCK_SIZE,
368 				   req->iv);
369 
370 	err = skcipher_walk_virt(&walk, &subreq, false);
371 	if (err)
372 		return err;
373 
374 	kernel_neon_begin();
375 	ce_aes_cbc_cts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
376 			       ctx->key_dec, num_rounds(ctx), walk.nbytes,
377 			       walk.iv);
378 	kernel_neon_end();
379 
380 	return skcipher_walk_done(&walk, 0);
381 }
382 
ctr_encrypt(struct skcipher_request * req)383 static int ctr_encrypt(struct skcipher_request *req)
384 {
385 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
386 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
387 	struct skcipher_walk walk;
388 	int err, blocks;
389 
390 	err = skcipher_walk_virt(&walk, req, false);
391 
392 	while ((blocks = (walk.nbytes / AES_BLOCK_SIZE))) {
393 		kernel_neon_begin();
394 		ce_aes_ctr_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
395 				   ctx->key_enc, num_rounds(ctx), blocks,
396 				   walk.iv);
397 		kernel_neon_end();
398 		err = skcipher_walk_done(&walk, walk.nbytes % AES_BLOCK_SIZE);
399 	}
400 	if (walk.nbytes) {
401 		u8 __aligned(8) tail[AES_BLOCK_SIZE];
402 		unsigned int nbytes = walk.nbytes;
403 		u8 *tdst = walk.dst.virt.addr;
404 		u8 *tsrc = walk.src.virt.addr;
405 
406 		/*
407 		 * Tell aes_ctr_encrypt() to process a tail block.
408 		 */
409 		blocks = -1;
410 
411 		kernel_neon_begin();
412 		ce_aes_ctr_encrypt(tail, NULL, ctx->key_enc, num_rounds(ctx),
413 				   blocks, walk.iv);
414 		kernel_neon_end();
415 		crypto_xor_cpy(tdst, tsrc, tail, nbytes);
416 		err = skcipher_walk_done(&walk, 0);
417 	}
418 	return err;
419 }
420 
ctr_encrypt_one(struct crypto_skcipher * tfm,const u8 * src,u8 * dst)421 static void ctr_encrypt_one(struct crypto_skcipher *tfm, const u8 *src, u8 *dst)
422 {
423 	struct crypto_aes_ctx *ctx = crypto_skcipher_ctx(tfm);
424 	unsigned long flags;
425 
426 	/*
427 	 * Temporarily disable interrupts to avoid races where
428 	 * cachelines are evicted when the CPU is interrupted
429 	 * to do something else.
430 	 */
431 	local_irq_save(flags);
432 	aes_encrypt(ctx, dst, src);
433 	local_irq_restore(flags);
434 }
435 
ctr_encrypt_sync(struct skcipher_request * req)436 static int ctr_encrypt_sync(struct skcipher_request *req)
437 {
438 	if (!crypto_simd_usable())
439 		return crypto_ctr_encrypt_walk(req, ctr_encrypt_one);
440 
441 	return ctr_encrypt(req);
442 }
443 
xts_encrypt(struct skcipher_request * req)444 static int xts_encrypt(struct skcipher_request *req)
445 {
446 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
447 	struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
448 	int err, first, rounds = num_rounds(&ctx->key1);
449 	int tail = req->cryptlen % AES_BLOCK_SIZE;
450 	struct scatterlist sg_src[2], sg_dst[2];
451 	struct skcipher_request subreq;
452 	struct scatterlist *src, *dst;
453 	struct skcipher_walk walk;
454 
455 	if (req->cryptlen < AES_BLOCK_SIZE)
456 		return -EINVAL;
457 
458 	err = skcipher_walk_virt(&walk, req, false);
459 
460 	if (unlikely(tail > 0 && walk.nbytes < walk.total)) {
461 		int xts_blocks = DIV_ROUND_UP(req->cryptlen,
462 					      AES_BLOCK_SIZE) - 2;
463 
464 		skcipher_walk_abort(&walk);
465 
466 		skcipher_request_set_tfm(&subreq, tfm);
467 		skcipher_request_set_callback(&subreq,
468 					      skcipher_request_flags(req),
469 					      NULL, NULL);
470 		skcipher_request_set_crypt(&subreq, req->src, req->dst,
471 					   xts_blocks * AES_BLOCK_SIZE,
472 					   req->iv);
473 		req = &subreq;
474 		err = skcipher_walk_virt(&walk, req, false);
475 	} else {
476 		tail = 0;
477 	}
478 
479 	for (first = 1; walk.nbytes >= AES_BLOCK_SIZE; first = 0) {
480 		int nbytes = walk.nbytes;
481 
482 		if (walk.nbytes < walk.total)
483 			nbytes &= ~(AES_BLOCK_SIZE - 1);
484 
485 		kernel_neon_begin();
486 		ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
487 				   ctx->key1.key_enc, rounds, nbytes, walk.iv,
488 				   ctx->key2.key_enc, first);
489 		kernel_neon_end();
490 		err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
491 	}
492 
493 	if (err || likely(!tail))
494 		return err;
495 
496 	dst = src = scatterwalk_ffwd(sg_src, req->src, req->cryptlen);
497 	if (req->dst != req->src)
498 		dst = scatterwalk_ffwd(sg_dst, req->dst, req->cryptlen);
499 
500 	skcipher_request_set_crypt(req, src, dst, AES_BLOCK_SIZE + tail,
501 				   req->iv);
502 
503 	err = skcipher_walk_virt(&walk, req, false);
504 	if (err)
505 		return err;
506 
507 	kernel_neon_begin();
508 	ce_aes_xts_encrypt(walk.dst.virt.addr, walk.src.virt.addr,
509 			   ctx->key1.key_enc, rounds, walk.nbytes, walk.iv,
510 			   ctx->key2.key_enc, first);
511 	kernel_neon_end();
512 
513 	return skcipher_walk_done(&walk, 0);
514 }
515 
xts_decrypt(struct skcipher_request * req)516 static int xts_decrypt(struct skcipher_request *req)
517 {
518 	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
519 	struct crypto_aes_xts_ctx *ctx = crypto_skcipher_ctx(tfm);
520 	int err, first, rounds = num_rounds(&ctx->key1);
521 	int tail = req->cryptlen % AES_BLOCK_SIZE;
522 	struct scatterlist sg_src[2], sg_dst[2];
523 	struct skcipher_request subreq;
524 	struct scatterlist *src, *dst;
525 	struct skcipher_walk walk;
526 
527 	if (req->cryptlen < AES_BLOCK_SIZE)
528 		return -EINVAL;
529 
530 	err = skcipher_walk_virt(&walk, req, false);
531 
532 	if (unlikely(tail > 0 && walk.nbytes < walk.total)) {
533 		int xts_blocks = DIV_ROUND_UP(req->cryptlen,
534 					      AES_BLOCK_SIZE) - 2;
535 
536 		skcipher_walk_abort(&walk);
537 
538 		skcipher_request_set_tfm(&subreq, tfm);
539 		skcipher_request_set_callback(&subreq,
540 					      skcipher_request_flags(req),
541 					      NULL, NULL);
542 		skcipher_request_set_crypt(&subreq, req->src, req->dst,
543 					   xts_blocks * AES_BLOCK_SIZE,
544 					   req->iv);
545 		req = &subreq;
546 		err = skcipher_walk_virt(&walk, req, false);
547 	} else {
548 		tail = 0;
549 	}
550 
551 	for (first = 1; walk.nbytes >= AES_BLOCK_SIZE; first = 0) {
552 		int nbytes = walk.nbytes;
553 
554 		if (walk.nbytes < walk.total)
555 			nbytes &= ~(AES_BLOCK_SIZE - 1);
556 
557 		kernel_neon_begin();
558 		ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
559 				   ctx->key1.key_dec, rounds, nbytes, walk.iv,
560 				   ctx->key2.key_enc, first);
561 		kernel_neon_end();
562 		err = skcipher_walk_done(&walk, walk.nbytes - nbytes);
563 	}
564 
565 	if (err || likely(!tail))
566 		return err;
567 
568 	dst = src = scatterwalk_ffwd(sg_src, req->src, req->cryptlen);
569 	if (req->dst != req->src)
570 		dst = scatterwalk_ffwd(sg_dst, req->dst, req->cryptlen);
571 
572 	skcipher_request_set_crypt(req, src, dst, AES_BLOCK_SIZE + tail,
573 				   req->iv);
574 
575 	err = skcipher_walk_virt(&walk, req, false);
576 	if (err)
577 		return err;
578 
579 	kernel_neon_begin();
580 	ce_aes_xts_decrypt(walk.dst.virt.addr, walk.src.virt.addr,
581 			   ctx->key1.key_dec, rounds, walk.nbytes, walk.iv,
582 			   ctx->key2.key_enc, first);
583 	kernel_neon_end();
584 
585 	return skcipher_walk_done(&walk, 0);
586 }
587 
588 static struct skcipher_alg aes_algs[] = { {
589 	.base.cra_name		= "__ecb(aes)",
590 	.base.cra_driver_name	= "__ecb-aes-ce",
591 	.base.cra_priority	= 300,
592 	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
593 	.base.cra_blocksize	= AES_BLOCK_SIZE,
594 	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
595 	.base.cra_module	= THIS_MODULE,
596 
597 	.min_keysize		= AES_MIN_KEY_SIZE,
598 	.max_keysize		= AES_MAX_KEY_SIZE,
599 	.setkey			= ce_aes_setkey,
600 	.encrypt		= ecb_encrypt,
601 	.decrypt		= ecb_decrypt,
602 }, {
603 	.base.cra_name		= "__cbc(aes)",
604 	.base.cra_driver_name	= "__cbc-aes-ce",
605 	.base.cra_priority	= 300,
606 	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
607 	.base.cra_blocksize	= AES_BLOCK_SIZE,
608 	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
609 	.base.cra_module	= THIS_MODULE,
610 
611 	.min_keysize		= AES_MIN_KEY_SIZE,
612 	.max_keysize		= AES_MAX_KEY_SIZE,
613 	.ivsize			= AES_BLOCK_SIZE,
614 	.setkey			= ce_aes_setkey,
615 	.encrypt		= cbc_encrypt,
616 	.decrypt		= cbc_decrypt,
617 }, {
618 	.base.cra_name		= "__cts(cbc(aes))",
619 	.base.cra_driver_name	= "__cts-cbc-aes-ce",
620 	.base.cra_priority	= 300,
621 	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
622 	.base.cra_blocksize	= AES_BLOCK_SIZE,
623 	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
624 	.base.cra_module	= THIS_MODULE,
625 
626 	.min_keysize		= AES_MIN_KEY_SIZE,
627 	.max_keysize		= AES_MAX_KEY_SIZE,
628 	.ivsize			= AES_BLOCK_SIZE,
629 	.walksize		= 2 * AES_BLOCK_SIZE,
630 	.setkey			= ce_aes_setkey,
631 	.encrypt		= cts_cbc_encrypt,
632 	.decrypt		= cts_cbc_decrypt,
633 }, {
634 	.base.cra_name		= "__ctr(aes)",
635 	.base.cra_driver_name	= "__ctr-aes-ce",
636 	.base.cra_priority	= 300,
637 	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
638 	.base.cra_blocksize	= 1,
639 	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
640 	.base.cra_module	= THIS_MODULE,
641 
642 	.min_keysize		= AES_MIN_KEY_SIZE,
643 	.max_keysize		= AES_MAX_KEY_SIZE,
644 	.ivsize			= AES_BLOCK_SIZE,
645 	.chunksize		= AES_BLOCK_SIZE,
646 	.setkey			= ce_aes_setkey,
647 	.encrypt		= ctr_encrypt,
648 	.decrypt		= ctr_encrypt,
649 }, {
650 	.base.cra_name		= "ctr(aes)",
651 	.base.cra_driver_name	= "ctr-aes-ce-sync",
652 	.base.cra_priority	= 300 - 1,
653 	.base.cra_blocksize	= 1,
654 	.base.cra_ctxsize	= sizeof(struct crypto_aes_ctx),
655 	.base.cra_module	= THIS_MODULE,
656 
657 	.min_keysize		= AES_MIN_KEY_SIZE,
658 	.max_keysize		= AES_MAX_KEY_SIZE,
659 	.ivsize			= AES_BLOCK_SIZE,
660 	.chunksize		= AES_BLOCK_SIZE,
661 	.setkey			= ce_aes_setkey,
662 	.encrypt		= ctr_encrypt_sync,
663 	.decrypt		= ctr_encrypt_sync,
664 }, {
665 	.base.cra_name		= "__xts(aes)",
666 	.base.cra_driver_name	= "__xts-aes-ce",
667 	.base.cra_priority	= 300,
668 	.base.cra_flags		= CRYPTO_ALG_INTERNAL,
669 	.base.cra_blocksize	= AES_BLOCK_SIZE,
670 	.base.cra_ctxsize	= sizeof(struct crypto_aes_xts_ctx),
671 	.base.cra_module	= THIS_MODULE,
672 
673 	.min_keysize		= 2 * AES_MIN_KEY_SIZE,
674 	.max_keysize		= 2 * AES_MAX_KEY_SIZE,
675 	.ivsize			= AES_BLOCK_SIZE,
676 	.walksize		= 2 * AES_BLOCK_SIZE,
677 	.setkey			= xts_set_key,
678 	.encrypt		= xts_encrypt,
679 	.decrypt		= xts_decrypt,
680 } };
681 
682 static struct simd_skcipher_alg *aes_simd_algs[ARRAY_SIZE(aes_algs)];
683 
aes_exit(void)684 static void aes_exit(void)
685 {
686 	int i;
687 
688 	for (i = 0; i < ARRAY_SIZE(aes_simd_algs) && aes_simd_algs[i]; i++)
689 		simd_skcipher_free(aes_simd_algs[i]);
690 
691 	crypto_unregister_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
692 }
693 
aes_init(void)694 static int __init aes_init(void)
695 {
696 	struct simd_skcipher_alg *simd;
697 	const char *basename;
698 	const char *algname;
699 	const char *drvname;
700 	int err;
701 	int i;
702 
703 	err = crypto_register_skciphers(aes_algs, ARRAY_SIZE(aes_algs));
704 	if (err)
705 		return err;
706 
707 	for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
708 		if (!(aes_algs[i].base.cra_flags & CRYPTO_ALG_INTERNAL))
709 			continue;
710 
711 		algname = aes_algs[i].base.cra_name + 2;
712 		drvname = aes_algs[i].base.cra_driver_name + 2;
713 		basename = aes_algs[i].base.cra_driver_name;
714 		simd = simd_skcipher_create_compat(aes_algs + i, algname, drvname, basename);
715 		err = PTR_ERR(simd);
716 		if (IS_ERR(simd))
717 			goto unregister_simds;
718 
719 		aes_simd_algs[i] = simd;
720 	}
721 
722 	return 0;
723 
724 unregister_simds:
725 	aes_exit();
726 	return err;
727 }
728 
729 module_cpu_feature_match(AES, aes_init);
730 module_exit(aes_exit);
731