1 /* 2 * Symmetric key cipher operations. 3 * 4 * Generic encrypt/decrypt wrapper for ciphers, handles operations across 5 * multiple page boundaries by using temporary blocks. In user context, 6 * the kernel is given a chance to schedule us once per page. 7 * 8 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au> 9 * 10 * This program is free software; you can redistribute it and/or modify it 11 * under the terms of the GNU General Public License as published by the Free 12 * Software Foundation; either version 2 of the License, or (at your option) 13 * any later version. 14 * 15 */ 16 17 #include <crypto/internal/aead.h> 18 #include <crypto/internal/skcipher.h> 19 #include <crypto/scatterwalk.h> 20 #include <linux/bug.h> 21 #include <linux/cryptouser.h> 22 #include <linux/list.h> 23 #include <linux/module.h> 24 #include <linux/rtnetlink.h> 25 #include <linux/seq_file.h> 26 #include <net/netlink.h> 27 28 #include "internal.h" 29 30 enum { 31 SKCIPHER_WALK_PHYS = 1 << 0, 32 SKCIPHER_WALK_SLOW = 1 << 1, 33 SKCIPHER_WALK_COPY = 1 << 2, 34 SKCIPHER_WALK_DIFF = 1 << 3, 35 SKCIPHER_WALK_SLEEP = 1 << 4, 36 }; 37 38 struct skcipher_walk_buffer { 39 struct list_head entry; 40 struct scatter_walk dst; 41 unsigned int len; 42 u8 *data; 43 u8 buffer[]; 44 }; 45 46 static int skcipher_walk_next(struct skcipher_walk *walk); 47 48 static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr) 49 { 50 if (PageHighMem(scatterwalk_page(walk))) 51 kunmap_atomic(vaddr); 52 } 53 54 static inline void *skcipher_map(struct scatter_walk *walk) 55 { 56 struct page *page = scatterwalk_page(walk); 57 58 return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) + 59 offset_in_page(walk->offset); 60 } 61 62 static inline void skcipher_map_src(struct skcipher_walk *walk) 63 { 64 walk->src.virt.addr = skcipher_map(&walk->in); 65 } 66 67 static inline void skcipher_map_dst(struct skcipher_walk *walk) 68 { 69 walk->dst.virt.addr = skcipher_map(&walk->out); 70 } 71 72 static inline void skcipher_unmap_src(struct skcipher_walk *walk) 73 { 74 skcipher_unmap(&walk->in, walk->src.virt.addr); 75 } 76 77 static inline void skcipher_unmap_dst(struct skcipher_walk *walk) 78 { 79 skcipher_unmap(&walk->out, walk->dst.virt.addr); 80 } 81 82 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk) 83 { 84 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC; 85 } 86 87 /* Get a spot of the specified length that does not straddle a page. 88 * The caller needs to ensure that there is enough space for this operation. 89 */ 90 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len) 91 { 92 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); 93 94 return max(start, end_page); 95 } 96 97 static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize) 98 { 99 u8 *addr; 100 101 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1); 102 addr = skcipher_get_spot(addr, bsize); 103 scatterwalk_copychunks(addr, &walk->out, bsize, 104 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1); 105 return 0; 106 } 107 108 int skcipher_walk_done(struct skcipher_walk *walk, int err) 109 { 110 unsigned int n = walk->nbytes - err; 111 unsigned int nbytes; 112 113 nbytes = walk->total - n; 114 115 if (unlikely(err < 0)) { 116 nbytes = 0; 117 n = 0; 118 } else 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 (WARN_ON(err)) { 133 err = -EINVAL; 134 nbytes = 0; 135 } else 136 n = skcipher_done_slow(walk, n); 137 } 138 139 if (err > 0) 140 err = 0; 141 142 walk->total = nbytes; 143 walk->nbytes = nbytes; 144 145 scatterwalk_advance(&walk->in, n); 146 scatterwalk_advance(&walk->out, n); 147 scatterwalk_done(&walk->in, 0, nbytes); 148 scatterwalk_done(&walk->out, 1, nbytes); 149 150 if (nbytes) { 151 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ? 152 CRYPTO_TFM_REQ_MAY_SLEEP : 0); 153 return skcipher_walk_next(walk); 154 } 155 156 /* Short-circuit for the common/fast path. */ 157 if (!((unsigned long)walk->buffer | (unsigned long)walk->page)) 158 goto out; 159 160 if (walk->flags & SKCIPHER_WALK_PHYS) 161 goto out; 162 163 if (walk->iv != walk->oiv) 164 memcpy(walk->oiv, walk->iv, walk->ivsize); 165 if (walk->buffer != walk->page) 166 kfree(walk->buffer); 167 if (walk->page) 168 free_page((unsigned long)walk->page); 169 170 out: 171 return err; 172 } 173 EXPORT_SYMBOL_GPL(skcipher_walk_done); 174 175 void skcipher_walk_complete(struct skcipher_walk *walk, int err) 176 { 177 struct skcipher_walk_buffer *p, *tmp; 178 179 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) { 180 u8 *data; 181 182 if (err) 183 goto done; 184 185 data = p->data; 186 if (!data) { 187 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1); 188 data = skcipher_get_spot(data, walk->chunksize); 189 } 190 191 scatterwalk_copychunks(data, &p->dst, p->len, 1); 192 193 if (offset_in_page(p->data) + p->len + walk->chunksize > 194 PAGE_SIZE) 195 free_page((unsigned long)p->data); 196 197 done: 198 list_del(&p->entry); 199 kfree(p); 200 } 201 202 if (!err && walk->iv != walk->oiv) 203 memcpy(walk->oiv, walk->iv, walk->ivsize); 204 if (walk->buffer != walk->page) 205 kfree(walk->buffer); 206 if (walk->page) 207 free_page((unsigned long)walk->page); 208 } 209 EXPORT_SYMBOL_GPL(skcipher_walk_complete); 210 211 static void skcipher_queue_write(struct skcipher_walk *walk, 212 struct skcipher_walk_buffer *p) 213 { 214 p->dst = walk->out; 215 list_add_tail(&p->entry, &walk->buffers); 216 } 217 218 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize) 219 { 220 bool phys = walk->flags & SKCIPHER_WALK_PHYS; 221 unsigned alignmask = walk->alignmask; 222 struct skcipher_walk_buffer *p; 223 unsigned a; 224 unsigned n; 225 u8 *buffer; 226 void *v; 227 228 if (!phys) { 229 if (!walk->buffer) 230 walk->buffer = walk->page; 231 buffer = walk->buffer; 232 if (buffer) 233 goto ok; 234 } 235 236 /* Start with the minimum alignment of kmalloc. */ 237 a = crypto_tfm_ctx_alignment() - 1; 238 n = bsize; 239 240 if (phys) { 241 /* Calculate the minimum alignment of p->buffer. */ 242 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1; 243 n += sizeof(*p); 244 } 245 246 /* Minimum size to align p->buffer by alignmask. */ 247 n += alignmask & ~a; 248 249 /* Minimum size to ensure p->buffer does not straddle a page. */ 250 n += (bsize - 1) & ~(alignmask | a); 251 252 v = kzalloc(n, skcipher_walk_gfp(walk)); 253 if (!v) 254 return skcipher_walk_done(walk, -ENOMEM); 255 256 if (phys) { 257 p = v; 258 p->len = bsize; 259 skcipher_queue_write(walk, p); 260 buffer = p->buffer; 261 } else { 262 walk->buffer = v; 263 buffer = v; 264 } 265 266 ok: 267 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1); 268 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize); 269 walk->src.virt.addr = walk->dst.virt.addr; 270 271 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0); 272 273 walk->nbytes = bsize; 274 walk->flags |= SKCIPHER_WALK_SLOW; 275 276 return 0; 277 } 278 279 static int skcipher_next_copy(struct skcipher_walk *walk) 280 { 281 struct skcipher_walk_buffer *p; 282 u8 *tmp = walk->page; 283 284 skcipher_map_src(walk); 285 memcpy(tmp, walk->src.virt.addr, walk->nbytes); 286 skcipher_unmap_src(walk); 287 288 walk->src.virt.addr = tmp; 289 walk->dst.virt.addr = tmp; 290 291 if (!(walk->flags & SKCIPHER_WALK_PHYS)) 292 return 0; 293 294 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk)); 295 if (!p) 296 return -ENOMEM; 297 298 p->data = walk->page; 299 p->len = walk->nbytes; 300 skcipher_queue_write(walk, p); 301 302 if (offset_in_page(walk->page) + walk->nbytes + walk->chunksize > 303 PAGE_SIZE) 304 walk->page = NULL; 305 else 306 walk->page += walk->nbytes; 307 308 return 0; 309 } 310 311 static int skcipher_next_fast(struct skcipher_walk *walk) 312 { 313 unsigned long diff; 314 315 walk->src.phys.page = scatterwalk_page(&walk->in); 316 walk->src.phys.offset = offset_in_page(walk->in.offset); 317 walk->dst.phys.page = scatterwalk_page(&walk->out); 318 walk->dst.phys.offset = offset_in_page(walk->out.offset); 319 320 if (walk->flags & SKCIPHER_WALK_PHYS) 321 return 0; 322 323 diff = walk->src.phys.offset - walk->dst.phys.offset; 324 diff |= walk->src.virt.page - walk->dst.virt.page; 325 326 skcipher_map_src(walk); 327 walk->dst.virt.addr = walk->src.virt.addr; 328 329 if (diff) { 330 walk->flags |= SKCIPHER_WALK_DIFF; 331 skcipher_map_dst(walk); 332 } 333 334 return 0; 335 } 336 337 static int skcipher_walk_next(struct skcipher_walk *walk) 338 { 339 unsigned int bsize; 340 unsigned int n; 341 int err; 342 343 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY | 344 SKCIPHER_WALK_DIFF); 345 346 n = walk->total; 347 bsize = min(walk->chunksize, max(n, walk->blocksize)); 348 n = scatterwalk_clamp(&walk->in, n); 349 n = scatterwalk_clamp(&walk->out, n); 350 351 if (unlikely(n < bsize)) { 352 if (unlikely(walk->total < walk->blocksize)) 353 return skcipher_walk_done(walk, -EINVAL); 354 355 slow_path: 356 err = skcipher_next_slow(walk, bsize); 357 goto set_phys_lowmem; 358 } 359 360 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) { 361 if (!walk->page) { 362 gfp_t gfp = skcipher_walk_gfp(walk); 363 364 walk->page = (void *)__get_free_page(gfp); 365 if (!walk->page) 366 goto slow_path; 367 } 368 369 walk->nbytes = min_t(unsigned, n, 370 PAGE_SIZE - offset_in_page(walk->page)); 371 walk->flags |= SKCIPHER_WALK_COPY; 372 err = skcipher_next_copy(walk); 373 goto set_phys_lowmem; 374 } 375 376 walk->nbytes = n; 377 378 return skcipher_next_fast(walk); 379 380 set_phys_lowmem: 381 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) { 382 walk->src.phys.page = virt_to_page(walk->src.virt.addr); 383 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr); 384 walk->src.phys.offset &= PAGE_SIZE - 1; 385 walk->dst.phys.offset &= PAGE_SIZE - 1; 386 } 387 return err; 388 } 389 EXPORT_SYMBOL_GPL(skcipher_walk_next); 390 391 static int skcipher_copy_iv(struct skcipher_walk *walk) 392 { 393 unsigned a = crypto_tfm_ctx_alignment() - 1; 394 unsigned alignmask = walk->alignmask; 395 unsigned ivsize = walk->ivsize; 396 unsigned bs = walk->chunksize; 397 unsigned aligned_bs; 398 unsigned size; 399 u8 *iv; 400 401 aligned_bs = ALIGN(bs, alignmask); 402 403 /* Minimum size to align buffer by alignmask. */ 404 size = alignmask & ~a; 405 406 if (walk->flags & SKCIPHER_WALK_PHYS) 407 size += ivsize; 408 else { 409 size += aligned_bs + ivsize; 410 411 /* Minimum size to ensure buffer does not straddle a page. */ 412 size += (bs - 1) & ~(alignmask | a); 413 } 414 415 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk)); 416 if (!walk->buffer) 417 return -ENOMEM; 418 419 iv = PTR_ALIGN(walk->buffer, alignmask + 1); 420 iv = skcipher_get_spot(iv, bs) + aligned_bs; 421 422 walk->iv = memcpy(iv, walk->iv, walk->ivsize); 423 return 0; 424 } 425 426 static int skcipher_walk_first(struct skcipher_walk *walk) 427 { 428 walk->nbytes = 0; 429 430 if (WARN_ON_ONCE(in_irq())) 431 return -EDEADLK; 432 433 if (unlikely(!walk->total)) 434 return 0; 435 436 walk->buffer = NULL; 437 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) { 438 int err = skcipher_copy_iv(walk); 439 if (err) 440 return err; 441 } 442 443 walk->page = NULL; 444 walk->nbytes = walk->total; 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 scatterwalk_start(&walk->in, req->src); 455 scatterwalk_start(&walk->out, req->dst); 456 457 walk->total = req->cryptlen; 458 walk->iv = req->iv; 459 walk->oiv = req->iv; 460 461 walk->flags &= ~SKCIPHER_WALK_SLEEP; 462 walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ? 463 SKCIPHER_WALK_SLEEP : 0; 464 465 walk->blocksize = crypto_skcipher_blocksize(tfm); 466 walk->chunksize = crypto_skcipher_chunksize(tfm); 467 walk->ivsize = crypto_skcipher_ivsize(tfm); 468 walk->alignmask = crypto_skcipher_alignmask(tfm); 469 470 return skcipher_walk_first(walk); 471 } 472 473 int skcipher_walk_virt(struct skcipher_walk *walk, 474 struct skcipher_request *req, bool atomic) 475 { 476 int err; 477 478 walk->flags &= ~SKCIPHER_WALK_PHYS; 479 480 err = skcipher_walk_skcipher(walk, req); 481 482 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0; 483 484 return err; 485 } 486 EXPORT_SYMBOL_GPL(skcipher_walk_virt); 487 488 void skcipher_walk_atomise(struct skcipher_walk *walk) 489 { 490 walk->flags &= ~SKCIPHER_WALK_SLEEP; 491 } 492 EXPORT_SYMBOL_GPL(skcipher_walk_atomise); 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->flags &= ~SKCIPHER_WALK_PHYS; 512 513 scatterwalk_start(&walk->in, req->src); 514 scatterwalk_start(&walk->out, req->dst); 515 516 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2); 517 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2); 518 519 walk->iv = req->iv; 520 walk->oiv = req->iv; 521 522 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) 523 walk->flags |= SKCIPHER_WALK_SLEEP; 524 else 525 walk->flags &= ~SKCIPHER_WALK_SLEEP; 526 527 walk->blocksize = crypto_aead_blocksize(tfm); 528 walk->chunksize = crypto_aead_chunksize(tfm); 529 walk->ivsize = crypto_aead_ivsize(tfm); 530 walk->alignmask = crypto_aead_alignmask(tfm); 531 532 err = skcipher_walk_first(walk); 533 534 if (atomic) 535 walk->flags &= ~SKCIPHER_WALK_SLEEP; 536 537 return err; 538 } 539 540 int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req, 541 bool atomic) 542 { 543 walk->total = req->cryptlen; 544 545 return skcipher_walk_aead_common(walk, req, atomic); 546 } 547 EXPORT_SYMBOL_GPL(skcipher_walk_aead); 548 549 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk, 550 struct aead_request *req, bool atomic) 551 { 552 walk->total = req->cryptlen; 553 554 return skcipher_walk_aead_common(walk, req, atomic); 555 } 556 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt); 557 558 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk, 559 struct aead_request *req, bool atomic) 560 { 561 struct crypto_aead *tfm = crypto_aead_reqtfm(req); 562 563 walk->total = req->cryptlen - crypto_aead_authsize(tfm); 564 565 return skcipher_walk_aead_common(walk, req, atomic); 566 } 567 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt); 568 569 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg) 570 { 571 if (alg->cra_type == &crypto_blkcipher_type) 572 return sizeof(struct crypto_blkcipher *); 573 574 if (alg->cra_type == &crypto_ablkcipher_type || 575 alg->cra_type == &crypto_givcipher_type) 576 return sizeof(struct crypto_ablkcipher *); 577 578 return crypto_alg_extsize(alg); 579 } 580 581 static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm, 582 const u8 *key, unsigned int keylen) 583 { 584 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm); 585 struct crypto_blkcipher *blkcipher = *ctx; 586 int err; 587 588 crypto_blkcipher_clear_flags(blkcipher, ~0); 589 crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) & 590 CRYPTO_TFM_REQ_MASK); 591 err = crypto_blkcipher_setkey(blkcipher, key, keylen); 592 crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) & 593 CRYPTO_TFM_RES_MASK); 594 595 return err; 596 } 597 598 static int skcipher_crypt_blkcipher(struct skcipher_request *req, 599 int (*crypt)(struct blkcipher_desc *, 600 struct scatterlist *, 601 struct scatterlist *, 602 unsigned int)) 603 { 604 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 605 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm); 606 struct blkcipher_desc desc = { 607 .tfm = *ctx, 608 .info = req->iv, 609 .flags = req->base.flags, 610 }; 611 612 613 return crypt(&desc, req->dst, req->src, req->cryptlen); 614 } 615 616 static int skcipher_encrypt_blkcipher(struct skcipher_request *req) 617 { 618 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); 619 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher); 620 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; 621 622 return skcipher_crypt_blkcipher(req, alg->encrypt); 623 } 624 625 static int skcipher_decrypt_blkcipher(struct skcipher_request *req) 626 { 627 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); 628 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher); 629 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher; 630 631 return skcipher_crypt_blkcipher(req, alg->decrypt); 632 } 633 634 static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm) 635 { 636 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm); 637 638 crypto_free_blkcipher(*ctx); 639 } 640 641 static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm) 642 { 643 struct crypto_alg *calg = tfm->__crt_alg; 644 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 645 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm); 646 struct crypto_blkcipher *blkcipher; 647 struct crypto_tfm *btfm; 648 649 if (!crypto_mod_get(calg)) 650 return -EAGAIN; 651 652 btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER, 653 CRYPTO_ALG_TYPE_MASK); 654 if (IS_ERR(btfm)) { 655 crypto_mod_put(calg); 656 return PTR_ERR(btfm); 657 } 658 659 blkcipher = __crypto_blkcipher_cast(btfm); 660 *ctx = blkcipher; 661 tfm->exit = crypto_exit_skcipher_ops_blkcipher; 662 663 skcipher->setkey = skcipher_setkey_blkcipher; 664 skcipher->encrypt = skcipher_encrypt_blkcipher; 665 skcipher->decrypt = skcipher_decrypt_blkcipher; 666 667 skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher); 668 skcipher->keysize = calg->cra_blkcipher.max_keysize; 669 670 return 0; 671 } 672 673 static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm, 674 const u8 *key, unsigned int keylen) 675 { 676 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm); 677 struct crypto_ablkcipher *ablkcipher = *ctx; 678 int err; 679 680 crypto_ablkcipher_clear_flags(ablkcipher, ~0); 681 crypto_ablkcipher_set_flags(ablkcipher, 682 crypto_skcipher_get_flags(tfm) & 683 CRYPTO_TFM_REQ_MASK); 684 err = crypto_ablkcipher_setkey(ablkcipher, key, keylen); 685 crypto_skcipher_set_flags(tfm, 686 crypto_ablkcipher_get_flags(ablkcipher) & 687 CRYPTO_TFM_RES_MASK); 688 689 return err; 690 } 691 692 static int skcipher_crypt_ablkcipher(struct skcipher_request *req, 693 int (*crypt)(struct ablkcipher_request *)) 694 { 695 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); 696 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm); 697 struct ablkcipher_request *subreq = skcipher_request_ctx(req); 698 699 ablkcipher_request_set_tfm(subreq, *ctx); 700 ablkcipher_request_set_callback(subreq, skcipher_request_flags(req), 701 req->base.complete, req->base.data); 702 ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen, 703 req->iv); 704 705 return crypt(subreq); 706 } 707 708 static int skcipher_encrypt_ablkcipher(struct skcipher_request *req) 709 { 710 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); 711 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher); 712 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; 713 714 return skcipher_crypt_ablkcipher(req, alg->encrypt); 715 } 716 717 static int skcipher_decrypt_ablkcipher(struct skcipher_request *req) 718 { 719 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req); 720 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher); 721 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; 722 723 return skcipher_crypt_ablkcipher(req, alg->decrypt); 724 } 725 726 static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm) 727 { 728 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm); 729 730 crypto_free_ablkcipher(*ctx); 731 } 732 733 static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm) 734 { 735 struct crypto_alg *calg = tfm->__crt_alg; 736 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 737 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm); 738 struct crypto_ablkcipher *ablkcipher; 739 struct crypto_tfm *abtfm; 740 741 if (!crypto_mod_get(calg)) 742 return -EAGAIN; 743 744 abtfm = __crypto_alloc_tfm(calg, 0, 0); 745 if (IS_ERR(abtfm)) { 746 crypto_mod_put(calg); 747 return PTR_ERR(abtfm); 748 } 749 750 ablkcipher = __crypto_ablkcipher_cast(abtfm); 751 *ctx = ablkcipher; 752 tfm->exit = crypto_exit_skcipher_ops_ablkcipher; 753 754 skcipher->setkey = skcipher_setkey_ablkcipher; 755 skcipher->encrypt = skcipher_encrypt_ablkcipher; 756 skcipher->decrypt = skcipher_decrypt_ablkcipher; 757 758 skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher); 759 skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) + 760 sizeof(struct ablkcipher_request); 761 skcipher->keysize = calg->cra_ablkcipher.max_keysize; 762 763 return 0; 764 } 765 766 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm) 767 { 768 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 769 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); 770 771 alg->exit(skcipher); 772 } 773 774 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm) 775 { 776 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm); 777 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher); 778 779 if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type) 780 return crypto_init_skcipher_ops_blkcipher(tfm); 781 782 if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type || 783 tfm->__crt_alg->cra_type == &crypto_givcipher_type) 784 return crypto_init_skcipher_ops_ablkcipher(tfm); 785 786 skcipher->setkey = alg->setkey; 787 skcipher->encrypt = alg->encrypt; 788 skcipher->decrypt = alg->decrypt; 789 skcipher->ivsize = alg->ivsize; 790 skcipher->keysize = alg->max_keysize; 791 792 if (alg->exit) 793 skcipher->base.exit = crypto_skcipher_exit_tfm; 794 795 if (alg->init) 796 return alg->init(skcipher); 797 798 return 0; 799 } 800 801 static void crypto_skcipher_free_instance(struct crypto_instance *inst) 802 { 803 struct skcipher_instance *skcipher = 804 container_of(inst, struct skcipher_instance, s.base); 805 806 skcipher->free(skcipher); 807 } 808 809 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) 810 __attribute__ ((unused)); 811 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg) 812 { 813 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg, 814 base); 815 816 seq_printf(m, "type : skcipher\n"); 817 seq_printf(m, "async : %s\n", 818 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no"); 819 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); 820 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize); 821 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize); 822 seq_printf(m, "ivsize : %u\n", skcipher->ivsize); 823 seq_printf(m, "chunksize : %u\n", skcipher->chunksize); 824 } 825 826 #ifdef CONFIG_NET 827 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg) 828 { 829 struct crypto_report_blkcipher rblkcipher; 830 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg, 831 base); 832 833 strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type)); 834 strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv)); 835 836 rblkcipher.blocksize = alg->cra_blocksize; 837 rblkcipher.min_keysize = skcipher->min_keysize; 838 rblkcipher.max_keysize = skcipher->max_keysize; 839 rblkcipher.ivsize = skcipher->ivsize; 840 841 if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER, 842 sizeof(struct crypto_report_blkcipher), &rblkcipher)) 843 goto nla_put_failure; 844 return 0; 845 846 nla_put_failure: 847 return -EMSGSIZE; 848 } 849 #else 850 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg) 851 { 852 return -ENOSYS; 853 } 854 #endif 855 856 static const struct crypto_type crypto_skcipher_type2 = { 857 .extsize = crypto_skcipher_extsize, 858 .init_tfm = crypto_skcipher_init_tfm, 859 .free = crypto_skcipher_free_instance, 860 #ifdef CONFIG_PROC_FS 861 .show = crypto_skcipher_show, 862 #endif 863 .report = crypto_skcipher_report, 864 .maskclear = ~CRYPTO_ALG_TYPE_MASK, 865 .maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK, 866 .type = CRYPTO_ALG_TYPE_SKCIPHER, 867 .tfmsize = offsetof(struct crypto_skcipher, base), 868 }; 869 870 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, 871 const char *name, u32 type, u32 mask) 872 { 873 spawn->base.frontend = &crypto_skcipher_type2; 874 return crypto_grab_spawn(&spawn->base, name, type, mask); 875 } 876 EXPORT_SYMBOL_GPL(crypto_grab_skcipher); 877 878 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name, 879 u32 type, u32 mask) 880 { 881 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask); 882 } 883 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher); 884 885 int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask) 886 { 887 return crypto_type_has_alg(alg_name, &crypto_skcipher_type2, 888 type, mask); 889 } 890 EXPORT_SYMBOL_GPL(crypto_has_skcipher2); 891 892 static int skcipher_prepare_alg(struct skcipher_alg *alg) 893 { 894 struct crypto_alg *base = &alg->base; 895 896 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8) 897 return -EINVAL; 898 899 if (!alg->chunksize) 900 alg->chunksize = base->cra_blocksize; 901 902 base->cra_type = &crypto_skcipher_type2; 903 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK; 904 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER; 905 906 return 0; 907 } 908 909 int crypto_register_skcipher(struct skcipher_alg *alg) 910 { 911 struct crypto_alg *base = &alg->base; 912 int err; 913 914 err = skcipher_prepare_alg(alg); 915 if (err) 916 return err; 917 918 return crypto_register_alg(base); 919 } 920 EXPORT_SYMBOL_GPL(crypto_register_skcipher); 921 922 void crypto_unregister_skcipher(struct skcipher_alg *alg) 923 { 924 crypto_unregister_alg(&alg->base); 925 } 926 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher); 927 928 int crypto_register_skciphers(struct skcipher_alg *algs, int count) 929 { 930 int i, ret; 931 932 for (i = 0; i < count; i++) { 933 ret = crypto_register_skcipher(&algs[i]); 934 if (ret) 935 goto err; 936 } 937 938 return 0; 939 940 err: 941 for (--i; i >= 0; --i) 942 crypto_unregister_skcipher(&algs[i]); 943 944 return ret; 945 } 946 EXPORT_SYMBOL_GPL(crypto_register_skciphers); 947 948 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count) 949 { 950 int i; 951 952 for (i = count - 1; i >= 0; --i) 953 crypto_unregister_skcipher(&algs[i]); 954 } 955 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers); 956 957 int skcipher_register_instance(struct crypto_template *tmpl, 958 struct skcipher_instance *inst) 959 { 960 int err; 961 962 err = skcipher_prepare_alg(&inst->alg); 963 if (err) 964 return err; 965 966 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst)); 967 } 968 EXPORT_SYMBOL_GPL(skcipher_register_instance); 969 970 MODULE_LICENSE("GPL"); 971 MODULE_DESCRIPTION("Symmetric key cipher type"); 972