1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Symmetric key cipher operations. 4 * 5 * Generic encrypt/decrypt wrapper for ciphers, handles operations across 6 * multiple page boundaries by using temporary blocks. In user context, 7 * the kernel is given a chance to schedule us once per page. 8 * 9 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au> 10 */ 11 12 #include <crypto/internal/aead.h> 13 #include <crypto/internal/cipher.h> 14 #include <crypto/internal/skcipher.h> 15 #include <crypto/scatterwalk.h> 16 #include <linux/bug.h> 17 #include <linux/cryptouser.h> 18 #include <linux/err.h> 19 #include <linux/kernel.h> 20 #include <linux/list.h> 21 #include <linux/mm.h> 22 #include <linux/module.h> 23 #include <linux/seq_file.h> 24 #include <linux/slab.h> 25 #include <linux/string.h> 26 #include <net/netlink.h> 27 #include "skcipher.h" 28 29 #define CRYPTO_ALG_TYPE_SKCIPHER_MASK 0x0000000e 30 31 enum { 32 SKCIPHER_WALK_PHYS = 1 << 0, 33 SKCIPHER_WALK_SLOW = 1 << 1, 34 SKCIPHER_WALK_COPY = 1 << 2, 35 SKCIPHER_WALK_DIFF = 1 << 3, 36 SKCIPHER_WALK_SLEEP = 1 << 4, 37 }; 38 39 struct skcipher_walk_buffer { 40 struct list_head entry; 41 struct scatter_walk dst; 42 unsigned int len; 43 u8 *data; 44 u8 buffer[]; 45 }; 46 47 static const struct crypto_type crypto_skcipher_type; 48 49 static int skcipher_walk_next(struct skcipher_walk *walk); 50 51 static inline void skcipher_map_src(struct skcipher_walk *walk) 52 { 53 walk->src.virt.addr = scatterwalk_map(&walk->in); 54 } 55 56 static inline void skcipher_map_dst(struct skcipher_walk *walk) 57 { 58 walk->dst.virt.addr = scatterwalk_map(&walk->out); 59 } 60 61 static inline void skcipher_unmap_src(struct skcipher_walk *walk) 62 { 63 scatterwalk_unmap(walk->src.virt.addr); 64 } 65 66 static inline void skcipher_unmap_dst(struct skcipher_walk *walk) 67 { 68 scatterwalk_unmap(walk->dst.virt.addr); 69 } 70 71 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk) 72 { 73 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC; 74 } 75 76 /* Get a spot of the specified length that does not straddle a page. 77 * The caller needs to ensure that there is enough space for this operation. 78 */ 79 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len) 80 { 81 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); 82 83 return max(start, end_page); 84 } 85 86 static inline struct skcipher_alg *__crypto_skcipher_alg( 87 struct crypto_alg *alg) 88 { 89 return container_of(alg, struct skcipher_alg, base); 90 } 91 92 static inline struct crypto_istat_cipher *skcipher_get_stat( 93 struct skcipher_alg *alg) 94 { 95 return skcipher_get_stat_common(&alg->co); 96 } 97 98 static inline int crypto_skcipher_errstat(struct skcipher_alg *alg, int err) 99 { 100 struct crypto_istat_cipher *istat = skcipher_get_stat(alg); 101 102 if (!IS_ENABLED(CONFIG_CRYPTO_STATS)) 103 return err; 104 105 if (err && err != -EINPROGRESS && err != -EBUSY) 106 atomic64_inc(&istat->err_cnt); 107 108 return err; 109 } 110 111 static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize) 112 { 113 u8 *addr; 114 115 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1); 116 addr = skcipher_get_spot(addr, bsize); 117 scatterwalk_copychunks(addr, &walk->out, bsize, 118 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1); 119 return 0; 120 } 121 122 int skcipher_walk_done(struct skcipher_walk *walk, int err) 123 { 124 unsigned int n = walk->nbytes; 125 unsigned int nbytes = 0; 126 127 if (!n) 128 goto finish; 129 130 if (likely(err >= 0)) { 131 n -= err; 132 nbytes = walk->total - n; 133 } 134 135 if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS | 136 SKCIPHER_WALK_SLOW | 137 SKCIPHER_WALK_COPY | 138 SKCIPHER_WALK_DIFF)))) { 139 unmap_src: 140 skcipher_unmap_src(walk); 141 } else if (walk->flags & SKCIPHER_WALK_DIFF) { 142 skcipher_unmap_dst(walk); 143 goto unmap_src; 144 } else if (walk->flags & SKCIPHER_WALK_COPY) { 145 skcipher_map_dst(walk); 146 memcpy(walk->dst.virt.addr, walk->page, n); 147 skcipher_unmap_dst(walk); 148 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) { 149 if (err > 0) { 150 /* 151 * Didn't process all bytes. Either the algorithm is 152 * broken, or this was the last step and it turned out 153 * the message wasn't evenly divisible into blocks but 154 * the algorithm requires it. 155 */ 156 err = -EINVAL; 157 nbytes = 0; 158 } else 159 n = skcipher_done_slow(walk, n); 160 } 161 162 if (err > 0) 163 err = 0; 164 165 walk->total = nbytes; 166 walk->nbytes = 0; 167 168 scatterwalk_advance(&walk->in, n); 169 scatterwalk_advance(&walk->out, n); 170 scatterwalk_done(&walk->in, 0, nbytes); 171 scatterwalk_done(&walk->out, 1, nbytes); 172 173 if (nbytes) { 174 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ? 175 CRYPTO_TFM_REQ_MAY_SLEEP : 0); 176 return skcipher_walk_next(walk); 177 } 178 179 finish: 180 /* Short-circuit for the common/fast path. */ 181 if (!((unsigned long)walk->buffer | (unsigned long)walk->page)) 182 goto out; 183 184 if (walk->flags & SKCIPHER_WALK_PHYS) 185 goto out; 186 187 if (walk->iv != walk->oiv) 188 memcpy(walk->oiv, walk->iv, walk->ivsize); 189 if (walk->buffer != walk->page) 190 kfree(walk->buffer); 191 if (walk->page) 192 free_page((unsigned long)walk->page); 193 194 out: 195 return err; 196 } 197 EXPORT_SYMBOL_GPL(skcipher_walk_done); 198 199 void skcipher_walk_complete(struct skcipher_walk *walk, int err) 200 { 201 struct skcipher_walk_buffer *p, *tmp; 202 203 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) { 204 u8 *data; 205 206 if (err) 207 goto done; 208 209 data = p->data; 210 if (!data) { 211 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1); 212 data = skcipher_get_spot(data, walk->stride); 213 } 214 215 scatterwalk_copychunks(data, &p->dst, p->len, 1); 216 217 if (offset_in_page(p->data) + p->len + walk->stride > 218 PAGE_SIZE) 219 free_page((unsigned long)p->data); 220 221 done: 222 list_del(&p->entry); 223 kfree(p); 224 } 225 226 if (!err && walk->iv != walk->oiv) 227 memcpy(walk->oiv, walk->iv, walk->ivsize); 228 if (walk->buffer != walk->page) 229 kfree(walk->buffer); 230 if (walk->page) 231 free_page((unsigned long)walk->page); 232 } 233 EXPORT_SYMBOL_GPL(skcipher_walk_complete); 234 235 static void skcipher_queue_write(struct skcipher_walk *walk, 236 struct skcipher_walk_buffer *p) 237 { 238 p->dst = walk->out; 239 list_add_tail(&p->entry, &walk->buffers); 240 } 241 242 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize) 243 { 244 bool phys = walk->flags & SKCIPHER_WALK_PHYS; 245 unsigned alignmask = walk->alignmask; 246 struct skcipher_walk_buffer *p; 247 unsigned a; 248 unsigned n; 249 u8 *buffer; 250 void *v; 251 252 if (!phys) { 253 if (!walk->buffer) 254 walk->buffer = walk->page; 255 buffer = walk->buffer; 256 if (buffer) 257 goto ok; 258 } 259 260 /* Start with the minimum alignment of kmalloc. */ 261 a = crypto_tfm_ctx_alignment() - 1; 262 n = bsize; 263 264 if (phys) { 265 /* Calculate the minimum alignment of p->buffer. */ 266 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1; 267 n += sizeof(*p); 268 } 269 270 /* Minimum size to align p->buffer by alignmask. */ 271 n += alignmask & ~a; 272 273 /* Minimum size to ensure p->buffer does not straddle a page. */ 274 n += (bsize - 1) & ~(alignmask | a); 275 276 v = kzalloc(n, skcipher_walk_gfp(walk)); 277 if (!v) 278 return skcipher_walk_done(walk, -ENOMEM); 279 280 if (phys) { 281 p = v; 282 p->len = bsize; 283 skcipher_queue_write(walk, p); 284 buffer = p->buffer; 285 } else { 286 walk->buffer = v; 287 buffer = v; 288 } 289 290 ok: 291 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1); 292 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize); 293 walk->src.virt.addr = walk->dst.virt.addr; 294 295 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0); 296 297 walk->nbytes = bsize; 298 walk->flags |= SKCIPHER_WALK_SLOW; 299 300 return 0; 301 } 302 303 static int skcipher_next_copy(struct skcipher_walk *walk) 304 { 305 struct skcipher_walk_buffer *p; 306 u8 *tmp = walk->page; 307 308 skcipher_map_src(walk); 309 memcpy(tmp, walk->src.virt.addr, walk->nbytes); 310 skcipher_unmap_src(walk); 311 312 walk->src.virt.addr = tmp; 313 walk->dst.virt.addr = tmp; 314 315 if (!(walk->flags & SKCIPHER_WALK_PHYS)) 316 return 0; 317 318 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk)); 319 if (!p) 320 return -ENOMEM; 321 322 p->data = walk->page; 323 p->len = walk->nbytes; 324 skcipher_queue_write(walk, p); 325 326 if (offset_in_page(walk->page) + walk->nbytes + walk->stride > 327 PAGE_SIZE) 328 walk->page = NULL; 329 else 330 walk->page += walk->nbytes; 331 332 return 0; 333 } 334 335 static int skcipher_next_fast(struct skcipher_walk *walk) 336 { 337 unsigned long diff; 338 339 walk->src.phys.page = scatterwalk_page(&walk->in); 340 walk->src.phys.offset = offset_in_page(walk->in.offset); 341 walk->dst.phys.page = scatterwalk_page(&walk->out); 342 walk->dst.phys.offset = offset_in_page(walk->out.offset); 343 344 if (walk->flags & SKCIPHER_WALK_PHYS) 345 return 0; 346 347 diff = walk->src.phys.offset - walk->dst.phys.offset; 348 diff |= walk->src.virt.page - walk->dst.virt.page; 349 350 skcipher_map_src(walk); 351 walk->dst.virt.addr = walk->src.virt.addr; 352 353 if (diff) { 354 walk->flags |= SKCIPHER_WALK_DIFF; 355 skcipher_map_dst(walk); 356 } 357 358 return 0; 359 } 360 361 static int skcipher_walk_next(struct skcipher_walk *walk) 362 { 363 unsigned int bsize; 364 unsigned int n; 365 int err; 366 367 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY | 368 SKCIPHER_WALK_DIFF); 369 370 n = walk->total; 371 bsize = min(walk->stride, max(n, walk->blocksize)); 372 n = scatterwalk_clamp(&walk->in, n); 373 n = scatterwalk_clamp(&walk->out, n); 374 375 if (unlikely(n < bsize)) { 376 if (unlikely(walk->total < walk->blocksize)) 377 return skcipher_walk_done(walk, -EINVAL); 378 379 slow_path: 380 err = skcipher_next_slow(walk, bsize); 381 goto set_phys_lowmem; 382 } 383 384 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) { 385 if (!walk->page) { 386 gfp_t gfp = skcipher_walk_gfp(walk); 387 388 walk->page = (void *)__get_free_page(gfp); 389 if (!walk->page) 390 goto slow_path; 391 } 392 393 walk->nbytes = min_t(unsigned, n, 394 PAGE_SIZE - offset_in_page(walk->page)); 395 walk->flags |= SKCIPHER_WALK_COPY; 396 err = skcipher_next_copy(walk); 397 goto set_phys_lowmem; 398 } 399 400 walk->nbytes = n; 401 402 return skcipher_next_fast(walk); 403 404 set_phys_lowmem: 405 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) { 406 walk->src.phys.page = virt_to_page(walk->src.virt.addr); 407 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr); 408 walk->src.phys.offset &= PAGE_SIZE - 1; 409 walk->dst.phys.offset &= PAGE_SIZE - 1; 410 } 411 return err; 412 } 413 414 static int skcipher_copy_iv(struct skcipher_walk *walk) 415 { 416 unsigned a = crypto_tfm_ctx_alignment() - 1; 417 unsigned alignmask = walk->alignmask; 418 unsigned ivsize = walk->ivsize; 419 unsigned bs = walk->stride; 420 unsigned aligned_bs; 421 unsigned size; 422 u8 *iv; 423 424 aligned_bs = ALIGN(bs, alignmask + 1); 425 426 /* Minimum size to align buffer by alignmask. */ 427 size = alignmask & ~a; 428 429 if (walk->flags & SKCIPHER_WALK_PHYS) 430 size += ivsize; 431 else { 432 size += aligned_bs + ivsize; 433 434 /* Minimum size to ensure buffer does not straddle a page. */ 435 size += (bs - 1) & ~(alignmask | a); 436 } 437 438 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk)); 439 if (!walk->buffer) 440 return -ENOMEM; 441 442 iv = PTR_ALIGN(walk->buffer, alignmask + 1); 443 iv = skcipher_get_spot(iv, bs) + aligned_bs; 444 445 walk->iv = memcpy(iv, walk->iv, walk->ivsize); 446 return 0; 447 } 448 449 static int skcipher_walk_first(struct skcipher_walk *walk) 450 { 451 if (WARN_ON_ONCE(in_hardirq())) 452 return -EDEADLK; 453 454 walk->buffer = NULL; 455 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) { 456 int err = skcipher_copy_iv(walk); 457 if (err) 458 return err; 459 } 460 461 walk->page = NULL; 462 463 return skcipher_walk_next(walk); 464 } 465 466 static int skcipher_walk_skcipher(struct skcipher_walk *walk, 467 struct skcipher_request *req) 468 { 469 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 470 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 471 472 walk->total = req->cryptlen; 473 walk->nbytes = 0; 474 walk->iv = req->iv; 475 walk->oiv = req->iv; 476 477 if (unlikely(!walk->total)) 478 return 0; 479 480 scatterwalk_start(&walk->in, req->src); 481 scatterwalk_start(&walk->out, req->dst); 482 483 walk->flags &= ~SKCIPHER_WALK_SLEEP; 484 walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? 485 SKCIPHER_WALK_SLEEP : 0; 486 487 walk->blocksize = crypto_skcipher_blocksize(tfm); 488 walk->ivsize = crypto_skcipher_ivsize(tfm); 489 walk->alignmask = crypto_skcipher_alignmask(tfm); 490 491 if (alg->co.base.cra_type != &crypto_skcipher_type) 492 walk->stride = alg->co.chunksize; 493 else 494 walk->stride = alg->walksize; 495 496 return skcipher_walk_first(walk); 497 } 498 499 int skcipher_walk_virt(struct skcipher_walk *walk, 500 struct skcipher_request *req, bool atomic) 501 { 502 int err; 503 504 might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP); 505 506 walk->flags &= ~SKCIPHER_WALK_PHYS; 507 508 err = skcipher_walk_skcipher(walk, req); 509 510 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0; 511 512 return err; 513 } 514 EXPORT_SYMBOL_GPL(skcipher_walk_virt); 515 516 int skcipher_walk_async(struct skcipher_walk *walk, 517 struct skcipher_request *req) 518 { 519 walk->flags |= SKCIPHER_WALK_PHYS; 520 521 INIT_LIST_HEAD(&walk->buffers); 522 523 return skcipher_walk_skcipher(walk, req); 524 } 525 EXPORT_SYMBOL_GPL(skcipher_walk_async); 526 527 static int skcipher_walk_aead_common(struct skcipher_walk *walk, 528 struct aead_request *req, bool atomic) 529 { 530 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 531 int err; 532 533 walk->nbytes = 0; 534 walk->iv = req->iv; 535 walk->oiv = req->iv; 536 537 if (unlikely(!walk->total)) 538 return 0; 539 540 walk->flags &= ~SKCIPHER_WALK_PHYS; 541 542 scatterwalk_start(&walk->in, req->src); 543 scatterwalk_start(&walk->out, req->dst); 544 545 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2); 546 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2); 547 548 scatterwalk_done(&walk->in, 0, walk->total); 549 scatterwalk_done(&walk->out, 0, walk->total); 550 551 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) 552 walk->flags |= SKCIPHER_WALK_SLEEP; 553 else 554 walk->flags &= ~SKCIPHER_WALK_SLEEP; 555 556 walk->blocksize = crypto_aead_blocksize(tfm); 557 walk->stride = crypto_aead_chunksize(tfm); 558 walk->ivsize = crypto_aead_ivsize(tfm); 559 walk->alignmask = crypto_aead_alignmask(tfm); 560 561 err = skcipher_walk_first(walk); 562 563 if (atomic) 564 walk->flags &= ~SKCIPHER_WALK_SLEEP; 565 566 return err; 567 } 568 569 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk, 570 struct aead_request *req, bool atomic) 571 { 572 walk->total = req->cryptlen; 573 574 return skcipher_walk_aead_common(walk, req, atomic); 575 } 576 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt); 577 578 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk, 579 struct aead_request *req, bool atomic) 580 { 581 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 582 583 walk->total = req->cryptlen - crypto_aead_authsize(tfm); 584 585 return skcipher_walk_aead_common(walk, req, atomic); 586 } 587 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt); 588 589 static void skcipher_set_needkey(struct crypto_skcipher *tfm) 590 { 591 if (crypto_skcipher_max_keysize(tfm) != 0) 592 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY); 593 } 594 595 static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm, 596 const u8 *key, unsigned int keylen) 597 { 598 unsigned long alignmask = crypto_skcipher_alignmask(tfm); 599 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm); 600 u8 *buffer, *alignbuffer; 601 unsigned long absize; 602 int ret; 603 604 absize = keylen + alignmask; 605 buffer = kmalloc(absize, GFP_ATOMIC); 606 if (!buffer) 607 return -ENOMEM; 608 609 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); 610 memcpy(alignbuffer, key, keylen); 611 ret = cipher->setkey(tfm, alignbuffer, keylen); 612 kfree_sensitive(buffer); 613 return ret; 614 } 615 616 int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key, 617 unsigned int keylen) 618 { 619 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm); 620 unsigned long alignmask = crypto_skcipher_alignmask(tfm); 621 int err; 622 623 if (cipher->co.base.cra_type != &crypto_skcipher_type) { 624 err = crypto_lskcipher_setkey_sg(tfm, key, keylen); 625 goto out; 626 } 627 628 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) 629 return -EINVAL; 630 631 if ((unsigned long)key & alignmask) 632 err = skcipher_setkey_unaligned(tfm, key, keylen); 633 else 634 err = cipher->setkey(tfm, key, keylen); 635 636 out: 637 if (unlikely(err)) { 638 skcipher_set_needkey(tfm); 639 return err; 640 } 641 642 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY); 643 return 0; 644 } 645 EXPORT_SYMBOL_GPL(crypto_skcipher_setkey); 646 647 int crypto_skcipher_encrypt(struct skcipher_request *req) 648 { 649 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 650 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 651 int ret; 652 653 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) { 654 struct crypto_istat_cipher *istat = skcipher_get_stat(alg); 655 656 atomic64_inc(&istat->encrypt_cnt); 657 atomic64_add(req->cryptlen, &istat->encrypt_tlen); 658 } 659 660 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 661 ret = -ENOKEY; 662 else if (alg->co.base.cra_type != &crypto_skcipher_type) 663 ret = crypto_lskcipher_encrypt_sg(req); 664 else 665 ret = alg->encrypt(req); 666 667 return crypto_skcipher_errstat(alg, ret); 668 } 669 EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt); 670 671 int crypto_skcipher_decrypt(struct skcipher_request *req) 672 { 673 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 674 struct skcipher_alg *alg = crypto_skcipher_alg(tfm); 675 int ret; 676 677 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) { 678 struct crypto_istat_cipher *istat = skcipher_get_stat(alg); 679 680 atomic64_inc(&istat->decrypt_cnt); 681 atomic64_add(req->cryptlen, &istat->decrypt_tlen); 682 } 683 684 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 685 ret = -ENOKEY; 686 else if (alg->co.base.cra_type != &crypto_skcipher_type) 687 ret = crypto_lskcipher_decrypt_sg(req); 688 else 689 ret = alg->decrypt(req); 690 691 return crypto_skcipher_errstat(alg, ret); 692 } 693 EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt); 694 695 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm) 696 { 697 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 698 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); 699 700 alg->exit(skcipher); 701 } 702 703 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm) 704 { 705 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 706 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); 707 708 skcipher_set_needkey(skcipher); 709 710 if (tfm->__crt_alg->cra_type != &crypto_skcipher_type) 711 return crypto_init_lskcipher_ops_sg(tfm); 712 713 if (alg->exit) 714 skcipher->base.exit = crypto_skcipher_exit_tfm; 715 716 if (alg->init) 717 return alg->init(skcipher); 718 719 return 0; 720 } 721 722 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg) 723 { 724 if (alg->cra_type != &crypto_skcipher_type) 725 return sizeof(struct crypto_lskcipher *); 726 727 return crypto_alg_extsize(alg); 728 } 729 730 static void crypto_skcipher_free_instance(struct crypto_instance *inst) 731 { 732 struct skcipher_instance *skcipher = 733 container_of(inst, struct skcipher_instance, s.base); 734 735 skcipher->free(skcipher); 736 } 737 738 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) 739 __maybe_unused; 740 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) 741 { 742 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg); 743 744 seq_printf(m, "type : skcipher\n"); 745 seq_printf(m, "async : %s\n", 746 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no"); 747 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); 748 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize); 749 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize); 750 seq_printf(m, "ivsize : %u\n", skcipher->ivsize); 751 seq_printf(m, "chunksize : %u\n", skcipher->chunksize); 752 seq_printf(m, "walksize : %u\n", skcipher->walksize); 753 } 754 755 static int __maybe_unused crypto_skcipher_report( 756 struct sk_buff *skb, struct crypto_alg *alg) 757 { 758 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg); 759 struct crypto_report_blkcipher rblkcipher; 760 761 memset(&rblkcipher, 0, sizeof(rblkcipher)); 762 763 strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type)); 764 strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv)); 765 766 rblkcipher.blocksize = alg->cra_blocksize; 767 rblkcipher.min_keysize = skcipher->min_keysize; 768 rblkcipher.max_keysize = skcipher->max_keysize; 769 rblkcipher.ivsize = skcipher->ivsize; 770 771 return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, 772 sizeof(rblkcipher), &rblkcipher); 773 } 774 775 static int __maybe_unused crypto_skcipher_report_stat( 776 struct sk_buff *skb, struct crypto_alg *alg) 777 { 778 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg); 779 struct crypto_istat_cipher *istat; 780 struct crypto_stat_cipher rcipher; 781 782 istat = skcipher_get_stat(skcipher); 783 784 memset(&rcipher, 0, sizeof(rcipher)); 785 786 strscpy(rcipher.type, "cipher", sizeof(rcipher.type)); 787 788 rcipher.stat_encrypt_cnt = atomic64_read(&istat->encrypt_cnt); 789 rcipher.stat_encrypt_tlen = atomic64_read(&istat->encrypt_tlen); 790 rcipher.stat_decrypt_cnt = atomic64_read(&istat->decrypt_cnt); 791 rcipher.stat_decrypt_tlen = atomic64_read(&istat->decrypt_tlen); 792 rcipher.stat_err_cnt = atomic64_read(&istat->err_cnt); 793 794 return nla_put(skb, CRYPTOCFGA_STAT_CIPHER, sizeof(rcipher), &rcipher); 795 } 796 797 static const struct crypto_type crypto_skcipher_type = { 798 .extsize = crypto_skcipher_extsize, 799 .init_tfm = crypto_skcipher_init_tfm, 800 .free = crypto_skcipher_free_instance, 801 #ifdef CONFIG_PROC_FS 802 .show = crypto_skcipher_show, 803 #endif 804 #if IS_ENABLED(CONFIG_CRYPTO_USER) 805 .report = crypto_skcipher_report, 806 #endif 807 #ifdef CONFIG_CRYPTO_STATS 808 .report_stat = crypto_skcipher_report_stat, 809 #endif 810 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 811 .maskset = CRYPTO_ALG_TYPE_SKCIPHER_MASK, 812 .type = CRYPTO_ALG_TYPE_SKCIPHER, 813 .tfmsize = offsetof(struct crypto_skcipher, base), 814 }; 815 816 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, 817 struct crypto_instance *inst, 818 const char *name, u32 type, u32 mask) 819 { 820 spawn->base.frontend = &crypto_skcipher_type; 821 return crypto_grab_spawn(&spawn->base, inst, name, type, mask); 822 } 823 EXPORT_SYMBOL_GPL(crypto_grab_skcipher); 824 825 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name, 826 u32 type, u32 mask) 827 { 828 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask); 829 } 830 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher); 831 832 struct crypto_sync_skcipher *crypto_alloc_sync_skcipher( 833 const char *alg_name, u32 type, u32 mask) 834 { 835 struct crypto_skcipher *tfm; 836 837 /* Only sync algorithms allowed. */ 838 mask |= CRYPTO_ALG_ASYNC | CRYPTO_ALG_SKCIPHER_REQSIZE_LARGE; 839 840 tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask); 841 842 /* 843 * Make sure we do not allocate something that might get used with 844 * an on-stack request: check the request size. 845 */ 846 if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) > 847 MAX_SYNC_SKCIPHER_REQSIZE)) { 848 crypto_free_skcipher(tfm); 849 return ERR_PTR(-EINVAL); 850 } 851 852 return (struct crypto_sync_skcipher *)tfm; 853 } 854 EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher); 855 856 int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask) 857 { 858 return crypto_type_has_alg(alg_name, &crypto_skcipher_type, type, mask); 859 } 860 EXPORT_SYMBOL_GPL(crypto_has_skcipher); 861 862 int skcipher_prepare_alg_common(struct skcipher_alg_common *alg) 863 { 864 struct crypto_istat_cipher *istat = skcipher_get_stat_common(alg); 865 struct crypto_alg *base = &alg->base; 866 867 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8) 868 return -EINVAL; 869 870 if (!alg->chunksize) 871 alg->chunksize = base->cra_blocksize; 872 873 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 874 875 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) 876 memset(istat, 0, sizeof(*istat)); 877 878 return 0; 879 } 880 881 static int skcipher_prepare_alg(struct skcipher_alg *alg) 882 { 883 struct crypto_alg *base = &alg->base; 884 int err; 885 886 err = skcipher_prepare_alg_common(&alg->co); 887 if (err) 888 return err; 889 890 if (alg->walksize > PAGE_SIZE / 8) 891 return -EINVAL; 892 893 if (!alg->walksize) 894 alg->walksize = alg->chunksize; 895 896 base->cra_type = &crypto_skcipher_type; 897 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER; 898 899 return 0; 900 } 901 902 int crypto_register_skcipher(struct skcipher_alg *alg) 903 { 904 struct crypto_alg *base = &alg->base; 905 int err; 906 907 err = skcipher_prepare_alg(alg); 908 if (err) 909 return err; 910 911 return crypto_register_alg(base); 912 } 913 EXPORT_SYMBOL_GPL(crypto_register_skcipher); 914 915 void crypto_unregister_skcipher(struct skcipher_alg *alg) 916 { 917 crypto_unregister_alg(&alg->base); 918 } 919 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher); 920 921 int crypto_register_skciphers(struct skcipher_alg *algs, int count) 922 { 923 int i, ret; 924 925 for (i = 0; i < count; i++) { 926 ret = crypto_register_skcipher(&algs[i]); 927 if (ret) 928 goto err; 929 } 930 931 return 0; 932 933 err: 934 for (--i; i >= 0; --i) 935 crypto_unregister_skcipher(&algs[i]); 936 937 return ret; 938 } 939 EXPORT_SYMBOL_GPL(crypto_register_skciphers); 940 941 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count) 942 { 943 int i; 944 945 for (i = count - 1; i >= 0; --i) 946 crypto_unregister_skcipher(&algs[i]); 947 } 948 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers); 949 950 int skcipher_register_instance(struct crypto_template *tmpl, 951 struct skcipher_instance *inst) 952 { 953 int err; 954 955 if (WARN_ON(!inst->free)) 956 return -EINVAL; 957 958 err = skcipher_prepare_alg(&inst->alg); 959 if (err) 960 return err; 961 962 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst)); 963 } 964 EXPORT_SYMBOL_GPL(skcipher_register_instance); 965 966 static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key, 967 unsigned int keylen) 968 { 969 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm); 970 971 crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK); 972 crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) & 973 CRYPTO_TFM_REQ_MASK); 974 return crypto_cipher_setkey(cipher, key, keylen); 975 } 976 977 static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm) 978 { 979 struct skcipher_instance *inst = skcipher_alg_instance(tfm); 980 struct crypto_cipher_spawn *spawn = skcipher_instance_ctx(inst); 981 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm); 982 struct crypto_cipher *cipher; 983 984 cipher = crypto_spawn_cipher(spawn); 985 if (IS_ERR(cipher)) 986 return PTR_ERR(cipher); 987 988 ctx->cipher = cipher; 989 return 0; 990 } 991 992 static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm) 993 { 994 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm); 995 996 crypto_free_cipher(ctx->cipher); 997 } 998 999 static void skcipher_free_instance_simple(struct skcipher_instance *inst) 1000 { 1001 crypto_drop_cipher(skcipher_instance_ctx(inst)); 1002 kfree(inst); 1003 } 1004 1005 /** 1006 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode 1007 * 1008 * Allocate an skcipher_instance for a simple block cipher mode of operation, 1009 * e.g. cbc or ecb. The instance context will have just a single crypto_spawn, 1010 * that for the underlying cipher. The {min,max}_keysize, ivsize, blocksize, 1011 * alignmask, and priority are set from the underlying cipher but can be 1012 * overridden if needed. The tfm context defaults to skcipher_ctx_simple, and 1013 * default ->setkey(), ->init(), and ->exit() methods are installed. 1014 * 1015 * @tmpl: the template being instantiated 1016 * @tb: the template parameters 1017 * 1018 * Return: a pointer to the new instance, or an ERR_PTR(). The caller still 1019 * needs to register the instance. 1020 */ 1021 struct skcipher_instance *skcipher_alloc_instance_simple( 1022 struct crypto_template *tmpl, struct rtattr **tb) 1023 { 1024 u32 mask; 1025 struct skcipher_instance *inst; 1026 struct crypto_cipher_spawn *spawn; 1027 struct crypto_alg *cipher_alg; 1028 int err; 1029 1030 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask); 1031 if (err) 1032 return ERR_PTR(err); 1033 1034 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); 1035 if (!inst) 1036 return ERR_PTR(-ENOMEM); 1037 spawn = skcipher_instance_ctx(inst); 1038 1039 err = crypto_grab_cipher(spawn, skcipher_crypto_instance(inst), 1040 crypto_attr_alg_name(tb[1]), 0, mask); 1041 if (err) 1042 goto err_free_inst; 1043 cipher_alg = crypto_spawn_cipher_alg(spawn); 1044 1045 err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name, 1046 cipher_alg); 1047 if (err) 1048 goto err_free_inst; 1049 1050 inst->free = skcipher_free_instance_simple; 1051 1052 /* Default algorithm properties, can be overridden */ 1053 inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize; 1054 inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask; 1055 inst->alg.base.cra_priority = cipher_alg->cra_priority; 1056 inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize; 1057 inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize; 1058 inst->alg.ivsize = cipher_alg->cra_blocksize; 1059 1060 /* Use skcipher_ctx_simple by default, can be overridden */ 1061 inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple); 1062 inst->alg.setkey = skcipher_setkey_simple; 1063 inst->alg.init = skcipher_init_tfm_simple; 1064 inst->alg.exit = skcipher_exit_tfm_simple; 1065 1066 return inst; 1067 1068 err_free_inst: 1069 skcipher_free_instance_simple(inst); 1070 return ERR_PTR(err); 1071 } 1072 EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple); 1073 1074 MODULE_LICENSE("GPL"); 1075 MODULE_DESCRIPTION("Symmetric key cipher type"); 1076 MODULE_IMPORT_NS(CRYPTO_INTERNAL); 1077