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