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Linux 4.19-rc7
[linux-2.6/btrfs-unstable.git] / arch / arm64 / crypto / ghash-ce-glue.c
blob067d8937d5af1e74a69ae7b14b1b0306a53fe087
1 /*
2 * Accelerated GHASH implementation with ARMv8 PMULL instructions.
3 *
4 * Copyright (C) 2014 - 2018 Linaro Ltd. <ard.biesheuvel@linaro.org>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 as published
8 * by the Free Software Foundation.
9 */
10
11 #include <asm/neon.h>
12 #include <asm/simd.h>
13 #include <asm/unaligned.h>
14 #include <crypto/aes.h>
15 #include <crypto/algapi.h>
16 #include <crypto/b128ops.h>
17 #include <crypto/gf128mul.h>
18 #include <crypto/internal/aead.h>
19 #include <crypto/internal/hash.h>
20 #include <crypto/internal/skcipher.h>
21 #include <crypto/scatterwalk.h>
22 #include <linux/cpufeature.h>
23 #include <linux/crypto.h>
24 #include <linux/module.h>
25
26 MODULE_DESCRIPTION("GHASH and AES-GCM using ARMv8 Crypto Extensions");
27 MODULE_AUTHOR("Ard Biesheuvel <ard.biesheuvel@linaro.org>");
28 MODULE_LICENSE("GPL v2");
29 MODULE_ALIAS_CRYPTO("ghash");
30
31 #define GHASH_BLOCK_SIZE 16
32 #define GHASH_DIGEST_SIZE 16
33 #define GCM_IV_SIZE 12
34
35 struct ghash_key {
36 u64 h[2];
37 u64 h2[2];
38 u64 h3[2];
39 u64 h4[2];
40
41 be128 k;
42 };
43
44 struct ghash_desc_ctx {
45 u64 digest[GHASH_DIGEST_SIZE/sizeof(u64)];
46 u8 buf[GHASH_BLOCK_SIZE];
47 u32 count;
48 };
49
50 struct gcm_aes_ctx {
51 struct crypto_aes_ctx aes_key;
52 struct ghash_key ghash_key;
53 };
54
55 asmlinkage void pmull_ghash_update_p64(int blocks, u64 dg[], const char *src,
56 struct ghash_key const *k,
57 const char *head);
58
59 asmlinkage void pmull_ghash_update_p8(int blocks, u64 dg[], const char *src,
60 struct ghash_key const *k,
61 const char *head);
62
63 static void (*pmull_ghash_update)(int blocks, u64 dg[], const char *src,
64 struct ghash_key const *k,
65 const char *head);
66
67 asmlinkage void pmull_gcm_encrypt(int blocks, u64 dg[], u8 dst[],
68 const u8 src[], struct ghash_key const *k,
69 u8 ctr[], u32 const rk[], int rounds,
70 u8 ks[]);
71
72 asmlinkage void pmull_gcm_decrypt(int blocks, u64 dg[], u8 dst[],
73 const u8 src[], struct ghash_key const *k,
74 u8 ctr[], u32 const rk[], int rounds);
75
76 asmlinkage void pmull_gcm_encrypt_block(u8 dst[], u8 const src[],
77 u32 const rk[], int rounds);
78
79 asmlinkage void __aes_arm64_encrypt(u32 *rk, u8 *out, const u8 *in, int rounds);
80
81 static int ghash_init(struct shash_desc *desc)
82 {
83 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
84
85 *ctx = (struct ghash_desc_ctx){};
86 return 0;
87 }
88
89 static void ghash_do_update(int blocks, u64 dg[], const char *src,
90 struct ghash_key *key, const char *head)
91 {
92 if (likely(may_use_simd())) {
93 kernel_neon_begin();
94 pmull_ghash_update(blocks, dg, src, key, head);
95 kernel_neon_end();
96 } else {
97 be128 dst = { cpu_to_be64(dg[1]), cpu_to_be64(dg[0]) };
98
99 do {
100 const u8 *in = src;
101
102 if (head) {
103 in = head;
104 blocks++;
105 head = NULL;
106 } else {
107 src += GHASH_BLOCK_SIZE;
108 }
109
110 crypto_xor((u8 *)&dst, in, GHASH_BLOCK_SIZE);
111 gf128mul_lle(&dst, &key->k);
112 } while (--blocks);
113
114 dg[0] = be64_to_cpu(dst.b);
115 dg[1] = be64_to_cpu(dst.a);
116 }
117 }
118
119 /* avoid hogging the CPU for too long */
120 #define MAX_BLOCKS (SZ_64K / GHASH_BLOCK_SIZE)
121
122 static int ghash_update(struct shash_desc *desc, const u8 *src,
123 unsigned int len)
124 {
125 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
126 unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
127
128 ctx->count += len;
129
130 if ((partial + len) >= GHASH_BLOCK_SIZE) {
131 struct ghash_key *key = crypto_shash_ctx(desc->tfm);
132 int blocks;
133
134 if (partial) {
135 int p = GHASH_BLOCK_SIZE - partial;
136
137 memcpy(ctx->buf + partial, src, p);
138 src += p;
139 len -= p;
140 }
141
142 blocks = len / GHASH_BLOCK_SIZE;
143 len %= GHASH_BLOCK_SIZE;
144
145 do {
146 int chunk = min(blocks, MAX_BLOCKS);
147
148 ghash_do_update(chunk, ctx->digest, src, key,
149 partial ? ctx->buf : NULL);
150
151 blocks -= chunk;
152 src += chunk * GHASH_BLOCK_SIZE;
153 partial = 0;
154 } while (unlikely(blocks > 0));
155 }
156 if (len)
157 memcpy(ctx->buf + partial, src, len);
158 return 0;
159 }
160
161 static int ghash_final(struct shash_desc *desc, u8 *dst)
162 {
163 struct ghash_desc_ctx *ctx = shash_desc_ctx(desc);
164 unsigned int partial = ctx->count % GHASH_BLOCK_SIZE;
165
166 if (partial) {
167 struct ghash_key *key = crypto_shash_ctx(desc->tfm);
168
169 memset(ctx->buf + partial, 0, GHASH_BLOCK_SIZE - partial);
170
171 ghash_do_update(1, ctx->digest, ctx->buf, key, NULL);
172 }
173 put_unaligned_be64(ctx->digest[1], dst);
174 put_unaligned_be64(ctx->digest[0], dst + 8);
175
176 *ctx = (struct ghash_desc_ctx){};
177 return 0;
178 }
179
180 static void ghash_reflect(u64 h[], const be128 *k)
181 {
182 u64 carry = be64_to_cpu(k->a) & BIT(63) ? 1 : 0;
183
184 h[0] = (be64_to_cpu(k->b) << 1) | carry;
185 h[1] = (be64_to_cpu(k->a) << 1) | (be64_to_cpu(k->b) >> 63);
186
187 if (carry)
188 h[1] ^= 0xc200000000000000UL;
189 }
190
191 static int __ghash_setkey(struct ghash_key *key,
192 const u8 *inkey, unsigned int keylen)
193 {
194 be128 h;
195
196 /* needed for the fallback */
197 memcpy(&key->k, inkey, GHASH_BLOCK_SIZE);
198
199 ghash_reflect(key->h, &key->k);
200
201 h = key->k;
202 gf128mul_lle(&h, &key->k);
203 ghash_reflect(key->h2, &h);
204
205 gf128mul_lle(&h, &key->k);
206 ghash_reflect(key->h3, &h);
207
208 gf128mul_lle(&h, &key->k);
209 ghash_reflect(key->h4, &h);
210
211 return 0;
212 }
213
214 static int ghash_setkey(struct crypto_shash *tfm,
215 const u8 *inkey, unsigned int keylen)
216 {
217 struct ghash_key *key = crypto_shash_ctx(tfm);
218
219 if (keylen != GHASH_BLOCK_SIZE) {
220 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
221 return -EINVAL;
222 }
223
224 return __ghash_setkey(key, inkey, keylen);
225 }
226
227 static struct shash_alg ghash_alg = {
228 .base.cra_name = "ghash",
229 .base.cra_driver_name = "ghash-ce",
230 .base.cra_priority = 200,
231 .base.cra_blocksize = GHASH_BLOCK_SIZE,
232 .base.cra_ctxsize = sizeof(struct ghash_key),
233 .base.cra_module = THIS_MODULE,
234
235 .digestsize = GHASH_DIGEST_SIZE,
236 .init = ghash_init,
237 .update = ghash_update,
238 .final = ghash_final,
239 .setkey = ghash_setkey,
240 .descsize = sizeof(struct ghash_desc_ctx),
241 };
242
243 static int num_rounds(struct crypto_aes_ctx *ctx)
244 {
245 /*
246 * # of rounds specified by AES:
247 * 128 bit key 10 rounds
248 * 192 bit key 12 rounds
249 * 256 bit key 14 rounds
250 * => n byte key => 6 + (n/4) rounds
251 */
252 return 6 + ctx->key_length / 4;
253 }
254
255 static int gcm_setkey(struct crypto_aead *tfm, const u8 *inkey,
256 unsigned int keylen)
257 {
258 struct gcm_aes_ctx *ctx = crypto_aead_ctx(tfm);
259 u8 key[GHASH_BLOCK_SIZE];
260 int ret;
261
262 ret = crypto_aes_expand_key(&ctx->aes_key, inkey, keylen);
263 if (ret) {
264 tfm->base.crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
265 return -EINVAL;
266 }
267
268 __aes_arm64_encrypt(ctx->aes_key.key_enc, key, (u8[AES_BLOCK_SIZE]){},
269 num_rounds(&ctx->aes_key));
270
271 return __ghash_setkey(&ctx->ghash_key, key, sizeof(be128));
272 }
273
274 static int gcm_setauthsize(struct crypto_aead *tfm, unsigned int authsize)
275 {
276 switch (authsize) {
277 case 4:
278 case 8:
279 case 12 ... 16:
280 break;
281 default:
282 return -EINVAL;
283 }
284 return 0;
285 }
286
287 static void gcm_update_mac(u64 dg[], const u8 *src, int count, u8 buf[],
288 int *buf_count, struct gcm_aes_ctx *ctx)
289 {
290 if (*buf_count > 0) {
291 int buf_added = min(count, GHASH_BLOCK_SIZE - *buf_count);
292
293 memcpy(&buf[*buf_count], src, buf_added);
294
295 *buf_count += buf_added;
296 src += buf_added;
297 count -= buf_added;
298 }
299
300 if (count >= GHASH_BLOCK_SIZE || *buf_count == GHASH_BLOCK_SIZE) {
301 int blocks = count / GHASH_BLOCK_SIZE;
302
303 ghash_do_update(blocks, dg, src, &ctx->ghash_key,
304 *buf_count ? buf : NULL);
305
306 src += blocks * GHASH_BLOCK_SIZE;
307 count %= GHASH_BLOCK_SIZE;
308 *buf_count = 0;
309 }
310
311 if (count > 0) {
312 memcpy(buf, src, count);
313 *buf_count = count;
314 }
315 }
316
317 static void gcm_calculate_auth_mac(struct aead_request *req, u64 dg[])
318 {
319 struct crypto_aead *aead = crypto_aead_reqtfm(req);
320 struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
321 u8 buf[GHASH_BLOCK_SIZE];
322 struct scatter_walk walk;
323 u32 len = req->assoclen;
324 int buf_count = 0;
325
326 scatterwalk_start(&walk, req->src);
327
328 do {
329 u32 n = scatterwalk_clamp(&walk, len);
330 u8 *p;
331
332 if (!n) {
333 scatterwalk_start(&walk, sg_next(walk.sg));
334 n = scatterwalk_clamp(&walk, len);
335 }
336 p = scatterwalk_map(&walk);
337
338 gcm_update_mac(dg, p, n, buf, &buf_count, ctx);
339 len -= n;
340
341 scatterwalk_unmap(p);
342 scatterwalk_advance(&walk, n);
343 scatterwalk_done(&walk, 0, len);
344 } while (len);
345
346 if (buf_count) {
347 memset(&buf[buf_count], 0, GHASH_BLOCK_SIZE - buf_count);
348 ghash_do_update(1, dg, buf, &ctx->ghash_key, NULL);
349 }
350 }
351
352 static void gcm_final(struct aead_request *req, struct gcm_aes_ctx *ctx,
353 u64 dg[], u8 tag[], int cryptlen)
354 {
355 u8 mac[AES_BLOCK_SIZE];
356 u128 lengths;
357
358 lengths.a = cpu_to_be64(req->assoclen * 8);
359 lengths.b = cpu_to_be64(cryptlen * 8);
360
361 ghash_do_update(1, dg, (void *)&lengths, &ctx->ghash_key, NULL);
362
363 put_unaligned_be64(dg[1], mac);
364 put_unaligned_be64(dg[0], mac + 8);
365
366 crypto_xor(tag, mac, AES_BLOCK_SIZE);
367 }
368
369 static int gcm_encrypt(struct aead_request *req)
370 {
371 struct crypto_aead *aead = crypto_aead_reqtfm(req);
372 struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
373 struct skcipher_walk walk;
374 u8 iv[AES_BLOCK_SIZE];
375 u8 ks[2 * AES_BLOCK_SIZE];
376 u8 tag[AES_BLOCK_SIZE];
377 u64 dg[2] = {};
378 int nrounds = num_rounds(&ctx->aes_key);
379 int err;
380
381 if (req->assoclen)
382 gcm_calculate_auth_mac(req, dg);
383
384 memcpy(iv, req->iv, GCM_IV_SIZE);
385 put_unaligned_be32(1, iv + GCM_IV_SIZE);
386
387 err = skcipher_walk_aead_encrypt(&walk, req, false);
388
389 if (likely(may_use_simd() && walk.total >= 2 * AES_BLOCK_SIZE)) {
390 u32 const *rk = NULL;
391
392 kernel_neon_begin();
393 pmull_gcm_encrypt_block(tag, iv, ctx->aes_key.key_enc, nrounds);
394 put_unaligned_be32(2, iv + GCM_IV_SIZE);
395 pmull_gcm_encrypt_block(ks, iv, NULL, nrounds);
396 put_unaligned_be32(3, iv + GCM_IV_SIZE);
397 pmull_gcm_encrypt_block(ks + AES_BLOCK_SIZE, iv, NULL, nrounds);
398 put_unaligned_be32(4, iv + GCM_IV_SIZE);
399
400 do {
401 int blocks = walk.nbytes / (2 * AES_BLOCK_SIZE) * 2;
402
403 if (rk)
404 kernel_neon_begin();
405
406 pmull_gcm_encrypt(blocks, dg, walk.dst.virt.addr,
407 walk.src.virt.addr, &ctx->ghash_key,
408 iv, rk, nrounds, ks);
409 kernel_neon_end();
410
411 err = skcipher_walk_done(&walk,
412 walk.nbytes % (2 * AES_BLOCK_SIZE));
413
414 rk = ctx->aes_key.key_enc;
415 } while (walk.nbytes >= 2 * AES_BLOCK_SIZE);
416 } else {
417 __aes_arm64_encrypt(ctx->aes_key.key_enc, tag, iv, nrounds);
418 put_unaligned_be32(2, iv + GCM_IV_SIZE);
419
420 while (walk.nbytes >= (2 * AES_BLOCK_SIZE)) {
421 int blocks = walk.nbytes / AES_BLOCK_SIZE;
422 u8 *dst = walk.dst.virt.addr;
423 u8 *src = walk.src.virt.addr;
424
425 do {
426 __aes_arm64_encrypt(ctx->aes_key.key_enc,
427 ks, iv, nrounds);
428 crypto_xor_cpy(dst, src, ks, AES_BLOCK_SIZE);
429 crypto_inc(iv, AES_BLOCK_SIZE);
430
431 dst += AES_BLOCK_SIZE;
432 src += AES_BLOCK_SIZE;
433 } while (--blocks > 0);
434
435 ghash_do_update(walk.nbytes / AES_BLOCK_SIZE, dg,
436 walk.dst.virt.addr, &ctx->ghash_key,
437 NULL);
438
439 err = skcipher_walk_done(&walk,
440 walk.nbytes % (2 * AES_BLOCK_SIZE));
441 }
442 if (walk.nbytes) {
443 __aes_arm64_encrypt(ctx->aes_key.key_enc, ks, iv,
444 nrounds);
445 if (walk.nbytes > AES_BLOCK_SIZE) {
446 crypto_inc(iv, AES_BLOCK_SIZE);
447 __aes_arm64_encrypt(ctx->aes_key.key_enc,
448 ks + AES_BLOCK_SIZE, iv,
449 nrounds);
450 }
451 }
452 }
453
454 /* handle the tail */
455 if (walk.nbytes) {
456 u8 buf[GHASH_BLOCK_SIZE];
457 unsigned int nbytes = walk.nbytes;
458 u8 *dst = walk.dst.virt.addr;
459 u8 *head = NULL;
460
461 crypto_xor_cpy(walk.dst.virt.addr, walk.src.virt.addr, ks,
462 walk.nbytes);
463
464 if (walk.nbytes > GHASH_BLOCK_SIZE) {
465 head = dst;
466 dst += GHASH_BLOCK_SIZE;
467 nbytes %= GHASH_BLOCK_SIZE;
468 }
469
470 memcpy(buf, dst, nbytes);
471 memset(buf + nbytes, 0, GHASH_BLOCK_SIZE - nbytes);
472 ghash_do_update(!!nbytes, dg, buf, &ctx->ghash_key, head);
473
474 err = skcipher_walk_done(&walk, 0);
475 }
476
477 if (err)
478 return err;
479
480 gcm_final(req, ctx, dg, tag, req->cryptlen);
481
482 /* copy authtag to end of dst */
483 scatterwalk_map_and_copy(tag, req->dst, req->assoclen + req->cryptlen,
484 crypto_aead_authsize(aead), 1);
485
486 return 0;
487 }
488
489 static int gcm_decrypt(struct aead_request *req)
490 {
491 struct crypto_aead *aead = crypto_aead_reqtfm(req);
492 struct gcm_aes_ctx *ctx = crypto_aead_ctx(aead);
493 unsigned int authsize = crypto_aead_authsize(aead);
494 struct skcipher_walk walk;
495 u8 iv[2 * AES_BLOCK_SIZE];
496 u8 tag[AES_BLOCK_SIZE];
497 u8 buf[2 * GHASH_BLOCK_SIZE];
498 u64 dg[2] = {};
499 int nrounds = num_rounds(&ctx->aes_key);
500 int err;
501
502 if (req->assoclen)
503 gcm_calculate_auth_mac(req, dg);
504
505 memcpy(iv, req->iv, GCM_IV_SIZE);
506 put_unaligned_be32(1, iv + GCM_IV_SIZE);
507
508 err = skcipher_walk_aead_decrypt(&walk, req, false);
509
510 if (likely(may_use_simd() && walk.total >= 2 * AES_BLOCK_SIZE)) {
511 u32 const *rk = NULL;
512
513 kernel_neon_begin();
514 pmull_gcm_encrypt_block(tag, iv, ctx->aes_key.key_enc, nrounds);
515 put_unaligned_be32(2, iv + GCM_IV_SIZE);
516
517 do {
518 int blocks = walk.nbytes / (2 * AES_BLOCK_SIZE) * 2;
519 int rem = walk.total - blocks * AES_BLOCK_SIZE;
520
521 if (rk)
522 kernel_neon_begin();
523
524 pmull_gcm_decrypt(blocks, dg, walk.dst.virt.addr,
525 walk.src.virt.addr, &ctx->ghash_key,
526 iv, rk, nrounds);
527
528 /* check if this is the final iteration of the loop */
529 if (rem < (2 * AES_BLOCK_SIZE)) {
530 u8 *iv2 = iv + AES_BLOCK_SIZE;
531
532 if (rem > AES_BLOCK_SIZE) {
533 memcpy(iv2, iv, AES_BLOCK_SIZE);
534 crypto_inc(iv2, AES_BLOCK_SIZE);
535 }
536
537 pmull_gcm_encrypt_block(iv, iv, NULL, nrounds);
538
539 if (rem > AES_BLOCK_SIZE)
540 pmull_gcm_encrypt_block(iv2, iv2, NULL,
541 nrounds);
542 }
543
544 kernel_neon_end();
545
546 err = skcipher_walk_done(&walk,
547 walk.nbytes % (2 * AES_BLOCK_SIZE));
548
549 rk = ctx->aes_key.key_enc;
550 } while (walk.nbytes >= 2 * AES_BLOCK_SIZE);
551 } else {
552 __aes_arm64_encrypt(ctx->aes_key.key_enc, tag, iv, nrounds);
553 put_unaligned_be32(2, iv + GCM_IV_SIZE);
554
555 while (walk.nbytes >= (2 * AES_BLOCK_SIZE)) {
556 int blocks = walk.nbytes / AES_BLOCK_SIZE;
557 u8 *dst = walk.dst.virt.addr;
558 u8 *src = walk.src.virt.addr;
559
560 ghash_do_update(blocks, dg, walk.src.virt.addr,
561 &ctx->ghash_key, NULL);
562
563 do {
564 __aes_arm64_encrypt(ctx->aes_key.key_enc,
565 buf, iv, nrounds);
566 crypto_xor_cpy(dst, src, buf, AES_BLOCK_SIZE);
567 crypto_inc(iv, AES_BLOCK_SIZE);
568
569 dst += AES_BLOCK_SIZE;
570 src += AES_BLOCK_SIZE;
571 } while (--blocks > 0);
572
573 err = skcipher_walk_done(&walk,
574 walk.nbytes % (2 * AES_BLOCK_SIZE));
575 }
576 if (walk.nbytes) {
577 if (walk.nbytes > AES_BLOCK_SIZE) {
578 u8 *iv2 = iv + AES_BLOCK_SIZE;
579
580 memcpy(iv2, iv, AES_BLOCK_SIZE);
581 crypto_inc(iv2, AES_BLOCK_SIZE);
582
583 __aes_arm64_encrypt(ctx->aes_key.key_enc, iv2,
584 iv2, nrounds);
585 }
586 __aes_arm64_encrypt(ctx->aes_key.key_enc, iv, iv,
587 nrounds);
588 }
589 }
590
591 /* handle the tail */
592 if (walk.nbytes) {
593 const u8 *src = walk.src.virt.addr;
594 const u8 *head = NULL;
595 unsigned int nbytes = walk.nbytes;
596
597 if (walk.nbytes > GHASH_BLOCK_SIZE) {
598 head = src;
599 src += GHASH_BLOCK_SIZE;
600 nbytes %= GHASH_BLOCK_SIZE;
601 }
602
603 memcpy(buf, src, nbytes);
604 memset(buf + nbytes, 0, GHASH_BLOCK_SIZE - nbytes);
605 ghash_do_update(!!nbytes, dg, buf, &ctx->ghash_key, head);
606
607 crypto_xor_cpy(walk.dst.virt.addr, walk.src.virt.addr, iv,
608 walk.nbytes);
609
610 err = skcipher_walk_done(&walk, 0);
611 }
612
613 if (err)
614 return err;
615
616 gcm_final(req, ctx, dg, tag, req->cryptlen - authsize);
617
618 /* compare calculated auth tag with the stored one */
619 scatterwalk_map_and_copy(buf, req->src,
620 req->assoclen + req->cryptlen - authsize,
621 authsize, 0);
622
623 if (crypto_memneq(tag, buf, authsize))
624 return -EBADMSG;
625 return 0;
626 }
627
628 static struct aead_alg gcm_aes_alg = {
629 .ivsize = GCM_IV_SIZE,
630 .chunksize = 2 * AES_BLOCK_SIZE,
631 .maxauthsize = AES_BLOCK_SIZE,
632 .setkey = gcm_setkey,
633 .setauthsize = gcm_setauthsize,
634 .encrypt = gcm_encrypt,
635 .decrypt = gcm_decrypt,
636
637 .base.cra_name = "gcm(aes)",
638 .base.cra_driver_name = "gcm-aes-ce",
639 .base.cra_priority = 300,
640 .base.cra_blocksize = 1,
641 .base.cra_ctxsize = sizeof(struct gcm_aes_ctx),
642 .base.cra_module = THIS_MODULE,
643 };
644
645 static int __init ghash_ce_mod_init(void)
646 {
647 int ret;
648
649 if (!(elf_hwcap & HWCAP_ASIMD))
650 return -ENODEV;
651
652 if (elf_hwcap & HWCAP_PMULL)
653 pmull_ghash_update = pmull_ghash_update_p64;
654
655 else
656 pmull_ghash_update = pmull_ghash_update_p8;
657
658 ret = crypto_register_shash(&ghash_alg);
659 if (ret)
660 return ret;
661
662 if (elf_hwcap & HWCAP_PMULL) {
663 ret = crypto_register_aead(&gcm_aes_alg);
664 if (ret)
665 crypto_unregister_shash(&ghash_alg);
666 }
667 return ret;
668 }
669
670 static void __exit ghash_ce_mod_exit(void)
671 {
672 crypto_unregister_shash(&ghash_alg);
673 crypto_unregister_aead(&gcm_aes_alg);
674 }
675
676 static const struct cpu_feature ghash_cpu_feature[] = {
677 { cpu_feature(PMULL) }, { }
678 };
679 MODULE_DEVICE_TABLE(cpu, ghash_cpu_feature);
680
681 module_init(ghash_ce_mod_init);
682 module_exit(ghash_ce_mod_exit);
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