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