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); 683