root/crypto/skcipher.c

DEFINITIONS

1. skcipher_unmap
2. skcipher_map
3. skcipher_map_src
4. skcipher_map_dst
5. skcipher_unmap_src
6. skcipher_unmap_dst
7. skcipher_walk_gfp
8. skcipher_get_spot
9. skcipher_done_slow
10. skcipher_walk_done
11. skcipher_walk_complete
12. skcipher_queue_write
13. skcipher_next_slow
14. skcipher_next_copy
15. skcipher_next_fast
16. skcipher_walk_next
17. skcipher_copy_iv
18. skcipher_walk_first
19. skcipher_walk_skcipher
20. skcipher_walk_virt
21. skcipher_walk_atomise
22. skcipher_walk_async
23. skcipher_walk_aead_common
24. skcipher_walk_aead
25. skcipher_walk_aead_encrypt
26. skcipher_walk_aead_decrypt
27. crypto_skcipher_extsize
28. skcipher_set_needkey
29. skcipher_setkey_blkcipher
30. skcipher_crypt_blkcipher
31. skcipher_encrypt_blkcipher
32. skcipher_decrypt_blkcipher
33. crypto_exit_skcipher_ops_blkcipher
34. crypto_init_skcipher_ops_blkcipher
35. skcipher_setkey_ablkcipher
36. skcipher_crypt_ablkcipher
37. skcipher_encrypt_ablkcipher
38. skcipher_decrypt_ablkcipher
39. crypto_exit_skcipher_ops_ablkcipher
40. crypto_init_skcipher_ops_ablkcipher
41. skcipher_setkey_unaligned
42. skcipher_setkey
43. crypto_skcipher_encrypt
44. crypto_skcipher_decrypt
45. crypto_skcipher_exit_tfm
46. crypto_skcipher_init_tfm
47. crypto_skcipher_free_instance
48. crypto_skcipher_show
49. crypto_skcipher_report
50. crypto_skcipher_report
51. crypto_grab_skcipher
52. crypto_alloc_skcipher
53. crypto_alloc_sync_skcipher
54. crypto_has_skcipher2
55. skcipher_prepare_alg
56. crypto_register_skcipher
57. crypto_unregister_skcipher
58. crypto_register_skciphers
59. crypto_unregister_skciphers
60. skcipher_register_instance
61. skcipher_setkey_simple
62. skcipher_init_tfm_simple
63. skcipher_exit_tfm_simple
64. skcipher_free_instance_simple
65. skcipher_alloc_instance_simple

   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/skcipher.h>
  14 #include <crypto/scatterwalk.h>
  15 #include <linux/bug.h>
  16 #include <linux/cryptouser.h>
  17 #include <linux/compiler.h>
  18 #include <linux/list.h>
  19 #include <linux/module.h>
  20 #include <linux/rtnetlink.h>
  21 #include <linux/seq_file.h>
  22 #include <net/netlink.h>
  23 
  24 #include "internal.h"
  25 
  26 enum {
  27         SKCIPHER_WALK_PHYS = 1 << 0,
  28         SKCIPHER_WALK_SLOW = 1 << 1,
  29         SKCIPHER_WALK_COPY = 1 << 2,
  30         SKCIPHER_WALK_DIFF = 1 << 3,
  31         SKCIPHER_WALK_SLEEP = 1 << 4,
  32 };
  33 
  34 struct skcipher_walk_buffer {
  35         struct list_head entry;
  36         struct scatter_walk dst;
  37         unsigned int len;
  38         u8 *data;
  39         u8 buffer[];
  40 };
  41 
  42 static int skcipher_walk_next(struct skcipher_walk *walk);
  43 
  44 static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr)
  45 {
  46         if (PageHighMem(scatterwalk_page(walk)))
  47                 kunmap_atomic(vaddr);
  48 }
  49 
  50 static inline void *skcipher_map(struct scatter_walk *walk)
  51 {
  52         struct page *page = scatterwalk_page(walk);
  53 
  54         return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) +
  55                offset_in_page(walk->offset);
  56 }
  57 
  58 static inline void skcipher_map_src(struct skcipher_walk *walk)
  59 {
  60         walk->src.virt.addr = skcipher_map(&walk->in);
  61 }
  62 
  63 static inline void skcipher_map_dst(struct skcipher_walk *walk)
  64 {
  65         walk->dst.virt.addr = skcipher_map(&walk->out);
  66 }
  67 
  68 static inline void skcipher_unmap_src(struct skcipher_walk *walk)
  69 {
  70         skcipher_unmap(&walk->in, walk->src.virt.addr);
  71 }
  72 
  73 static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
  74 {
  75         skcipher_unmap(&walk->out, walk->dst.virt.addr);
  76 }
  77 
  78 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
  79 {
  80         return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
  81 }
  82 
  83 /* Get a spot of the specified length that does not straddle a page.
  84  * The caller needs to ensure that there is enough space for this operation.
  85  */
  86 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
  87 {
  88         u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
  89 
  90         return max(start, end_page);
  91 }
  92 
  93 static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
  94 {
  95         u8 *addr;
  96 
  97         addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
  98         addr = skcipher_get_spot(addr, bsize);
  99         scatterwalk_copychunks(addr, &walk->out, bsize,
 100                                (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
 101         return 0;
 102 }
 103 
 104 int skcipher_walk_done(struct skcipher_walk *walk, int err)
 105 {
 106         unsigned int n = walk->nbytes;
 107         unsigned int nbytes = 0;
 108 
 109         if (!n)
 110                 goto finish;
 111 
 112         if (likely(err >= 0)) {
 113                 n -= err;
 114                 nbytes = walk->total - n;
 115         }
 116 
 117         if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
 118                                     SKCIPHER_WALK_SLOW |
 119                                     SKCIPHER_WALK_COPY |
 120                                     SKCIPHER_WALK_DIFF)))) {
 121 unmap_src:
 122                 skcipher_unmap_src(walk);
 123         } else if (walk->flags & SKCIPHER_WALK_DIFF) {
 124                 skcipher_unmap_dst(walk);
 125                 goto unmap_src;
 126         } else if (walk->flags & SKCIPHER_WALK_COPY) {
 127                 skcipher_map_dst(walk);
 128                 memcpy(walk->dst.virt.addr, walk->page, n);
 129                 skcipher_unmap_dst(walk);
 130         } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
 131                 if (err > 0) {
 132                         /*
 133                          * Didn't process all bytes.  Either the algorithm is
 134                          * broken, or this was the last step and it turned out
 135                          * the message wasn't evenly divisible into blocks but
 136                          * the algorithm requires it.
 137                          */
 138                         err = -EINVAL;
 139                         nbytes = 0;
 140                 } else
 141                         n = skcipher_done_slow(walk, n);
 142         }
 143 
 144         if (err > 0)
 145                 err = 0;
 146 
 147         walk->total = nbytes;
 148         walk->nbytes = 0;
 149 
 150         scatterwalk_advance(&walk->in, n);
 151         scatterwalk_advance(&walk->out, n);
 152         scatterwalk_done(&walk->in, 0, nbytes);
 153         scatterwalk_done(&walk->out, 1, nbytes);
 154 
 155         if (nbytes) {
 156                 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
 157                              CRYPTO_TFM_REQ_MAY_SLEEP : 0);
 158                 return skcipher_walk_next(walk);
 159         }
 160 
 161 finish:
 162         /* Short-circuit for the common/fast path. */
 163         if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
 164                 goto out;
 165 
 166         if (walk->flags & SKCIPHER_WALK_PHYS)
 167                 goto out;
 168 
 169         if (walk->iv != walk->oiv)
 170                 memcpy(walk->oiv, walk->iv, walk->ivsize);
 171         if (walk->buffer != walk->page)
 172                 kfree(walk->buffer);
 173         if (walk->page)
 174                 free_page((unsigned long)walk->page);
 175 
 176 out:
 177         return err;
 178 }
 179 EXPORT_SYMBOL_GPL(skcipher_walk_done);
 180 
 181 void skcipher_walk_complete(struct skcipher_walk *walk, int err)
 182 {
 183         struct skcipher_walk_buffer *p, *tmp;
 184 
 185         list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
 186                 u8 *data;
 187 
 188                 if (err)
 189                         goto done;
 190 
 191                 data = p->data;
 192                 if (!data) {
 193                         data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
 194                         data = skcipher_get_spot(data, walk->stride);
 195                 }
 196 
 197                 scatterwalk_copychunks(data, &p->dst, p->len, 1);
 198 
 199                 if (offset_in_page(p->data) + p->len + walk->stride >
 200                     PAGE_SIZE)
 201                         free_page((unsigned long)p->data);
 202 
 203 done:
 204                 list_del(&p->entry);
 205                 kfree(p);
 206         }
 207 
 208         if (!err && walk->iv != walk->oiv)
 209                 memcpy(walk->oiv, walk->iv, walk->ivsize);
 210         if (walk->buffer != walk->page)
 211                 kfree(walk->buffer);
 212         if (walk->page)
 213                 free_page((unsigned long)walk->page);
 214 }
 215 EXPORT_SYMBOL_GPL(skcipher_walk_complete);
 216 
 217 static void skcipher_queue_write(struct skcipher_walk *walk,
 218                                  struct skcipher_walk_buffer *p)
 219 {
 220         p->dst = walk->out;
 221         list_add_tail(&p->entry, &walk->buffers);
 222 }
 223 
 224 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
 225 {
 226         bool phys = walk->flags & SKCIPHER_WALK_PHYS;
 227         unsigned alignmask = walk->alignmask;
 228         struct skcipher_walk_buffer *p;
 229         unsigned a;
 230         unsigned n;
 231         u8 *buffer;
 232         void *v;
 233 
 234         if (!phys) {
 235                 if (!walk->buffer)
 236                         walk->buffer = walk->page;
 237                 buffer = walk->buffer;
 238                 if (buffer)
 239                         goto ok;
 240         }
 241 
 242         /* Start with the minimum alignment of kmalloc. */
 243         a = crypto_tfm_ctx_alignment() - 1;
 244         n = bsize;
 245 
 246         if (phys) {
 247                 /* Calculate the minimum alignment of p->buffer. */
 248                 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
 249                 n += sizeof(*p);
 250         }
 251 
 252         /* Minimum size to align p->buffer by alignmask. */
 253         n += alignmask & ~a;
 254 
 255         /* Minimum size to ensure p->buffer does not straddle a page. */
 256         n += (bsize - 1) & ~(alignmask | a);
 257 
 258         v = kzalloc(n, skcipher_walk_gfp(walk));
 259         if (!v)
 260                 return skcipher_walk_done(walk, -ENOMEM);
 261 
 262         if (phys) {
 263                 p = v;
 264                 p->len = bsize;
 265                 skcipher_queue_write(walk, p);
 266                 buffer = p->buffer;
 267         } else {
 268                 walk->buffer = v;
 269                 buffer = v;
 270         }
 271 
 272 ok:
 273         walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
 274         walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
 275         walk->src.virt.addr = walk->dst.virt.addr;
 276 
 277         scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
 278 
 279         walk->nbytes = bsize;
 280         walk->flags |= SKCIPHER_WALK_SLOW;
 281 
 282         return 0;
 283 }
 284 
 285 static int skcipher_next_copy(struct skcipher_walk *walk)
 286 {
 287         struct skcipher_walk_buffer *p;
 288         u8 *tmp = walk->page;
 289 
 290         skcipher_map_src(walk);
 291         memcpy(tmp, walk->src.virt.addr, walk->nbytes);
 292         skcipher_unmap_src(walk);
 293 
 294         walk->src.virt.addr = tmp;
 295         walk->dst.virt.addr = tmp;
 296 
 297         if (!(walk->flags & SKCIPHER_WALK_PHYS))
 298                 return 0;
 299 
 300         p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
 301         if (!p)
 302                 return -ENOMEM;
 303 
 304         p->data = walk->page;
 305         p->len = walk->nbytes;
 306         skcipher_queue_write(walk, p);
 307 
 308         if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
 309             PAGE_SIZE)
 310                 walk->page = NULL;
 311         else
 312                 walk->page += walk->nbytes;
 313 
 314         return 0;
 315 }
 316 
 317 static int skcipher_next_fast(struct skcipher_walk *walk)
 318 {
 319         unsigned long diff;
 320 
 321         walk->src.phys.page = scatterwalk_page(&walk->in);
 322         walk->src.phys.offset = offset_in_page(walk->in.offset);
 323         walk->dst.phys.page = scatterwalk_page(&walk->out);
 324         walk->dst.phys.offset = offset_in_page(walk->out.offset);
 325 
 326         if (walk->flags & SKCIPHER_WALK_PHYS)
 327                 return 0;
 328 
 329         diff = walk->src.phys.offset - walk->dst.phys.offset;
 330         diff |= walk->src.virt.page - walk->dst.virt.page;
 331 
 332         skcipher_map_src(walk);
 333         walk->dst.virt.addr = walk->src.virt.addr;
 334 
 335         if (diff) {
 336                 walk->flags |= SKCIPHER_WALK_DIFF;
 337                 skcipher_map_dst(walk);
 338         }
 339 
 340         return 0;
 341 }
 342 
 343 static int skcipher_walk_next(struct skcipher_walk *walk)
 344 {
 345         unsigned int bsize;
 346         unsigned int n;
 347         int err;
 348 
 349         walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
 350                          SKCIPHER_WALK_DIFF);
 351 
 352         n = walk->total;
 353         bsize = min(walk->stride, max(n, walk->blocksize));
 354         n = scatterwalk_clamp(&walk->in, n);
 355         n = scatterwalk_clamp(&walk->out, n);
 356 
 357         if (unlikely(n < bsize)) {
 358                 if (unlikely(walk->total < walk->blocksize))
 359                         return skcipher_walk_done(walk, -EINVAL);
 360 
 361 slow_path:
 362                 err = skcipher_next_slow(walk, bsize);
 363                 goto set_phys_lowmem;
 364         }
 365 
 366         if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
 367                 if (!walk->page) {
 368                         gfp_t gfp = skcipher_walk_gfp(walk);
 369 
 370                         walk->page = (void *)__get_free_page(gfp);
 371                         if (!walk->page)
 372                                 goto slow_path;
 373                 }
 374 
 375                 walk->nbytes = min_t(unsigned, n,
 376                                      PAGE_SIZE - offset_in_page(walk->page));
 377                 walk->flags |= SKCIPHER_WALK_COPY;
 378                 err = skcipher_next_copy(walk);
 379                 goto set_phys_lowmem;
 380         }
 381 
 382         walk->nbytes = n;
 383 
 384         return skcipher_next_fast(walk);
 385 
 386 set_phys_lowmem:
 387         if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
 388                 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
 389                 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
 390                 walk->src.phys.offset &= PAGE_SIZE - 1;
 391                 walk->dst.phys.offset &= PAGE_SIZE - 1;
 392         }
 393         return err;
 394 }
 395 
 396 static int skcipher_copy_iv(struct skcipher_walk *walk)
 397 {
 398         unsigned a = crypto_tfm_ctx_alignment() - 1;
 399         unsigned alignmask = walk->alignmask;
 400         unsigned ivsize = walk->ivsize;
 401         unsigned bs = walk->stride;
 402         unsigned aligned_bs;
 403         unsigned size;
 404         u8 *iv;
 405 
 406         aligned_bs = ALIGN(bs, alignmask + 1);
 407 
 408         /* Minimum size to align buffer by alignmask. */
 409         size = alignmask & ~a;
 410 
 411         if (walk->flags & SKCIPHER_WALK_PHYS)
 412                 size += ivsize;
 413         else {
 414                 size += aligned_bs + ivsize;
 415 
 416                 /* Minimum size to ensure buffer does not straddle a page. */
 417                 size += (bs - 1) & ~(alignmask | a);
 418         }
 419 
 420         walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
 421         if (!walk->buffer)
 422                 return -ENOMEM;
 423 
 424         iv = PTR_ALIGN(walk->buffer, alignmask + 1);
 425         iv = skcipher_get_spot(iv, bs) + aligned_bs;
 426 
 427         walk->iv = memcpy(iv, walk->iv, walk->ivsize);
 428         return 0;
 429 }
 430 
 431 static int skcipher_walk_first(struct skcipher_walk *walk)
 432 {
 433         if (WARN_ON_ONCE(in_irq()))
 434                 return -EDEADLK;
 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 
 445         return skcipher_walk_next(walk);
 446 }
 447 
 448 static int skcipher_walk_skcipher(struct skcipher_walk *walk,
 449                                   struct skcipher_request *req)
 450 {
 451         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 452 
 453         walk->total = req->cryptlen;
 454         walk->nbytes = 0;
 455         walk->iv = req->iv;
 456         walk->oiv = req->iv;
 457 
 458         if (unlikely(!walk->total))
 459                 return 0;
 460 
 461         scatterwalk_start(&walk->in, req->src);
 462         scatterwalk_start(&walk->out, req->dst);
 463 
 464         walk->flags &= ~SKCIPHER_WALK_SLEEP;
 465         walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
 466                        SKCIPHER_WALK_SLEEP : 0;
 467 
 468         walk->blocksize = crypto_skcipher_blocksize(tfm);
 469         walk->stride = crypto_skcipher_walksize(tfm);
 470         walk->ivsize = crypto_skcipher_ivsize(tfm);
 471         walk->alignmask = crypto_skcipher_alignmask(tfm);
 472 
 473         return skcipher_walk_first(walk);
 474 }
 475 
 476 int skcipher_walk_virt(struct skcipher_walk *walk,
 477                        struct skcipher_request *req, bool atomic)
 478 {
 479         int err;
 480 
 481         might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
 482 
 483         walk->flags &= ~SKCIPHER_WALK_PHYS;
 484 
 485         err = skcipher_walk_skcipher(walk, req);
 486 
 487         walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
 488 
 489         return err;
 490 }
 491 EXPORT_SYMBOL_GPL(skcipher_walk_virt);
 492 
 493 void skcipher_walk_atomise(struct skcipher_walk *walk)
 494 {
 495         walk->flags &= ~SKCIPHER_WALK_SLEEP;
 496 }
 497 EXPORT_SYMBOL_GPL(skcipher_walk_atomise);
 498 
 499 int skcipher_walk_async(struct skcipher_walk *walk,
 500                         struct skcipher_request *req)
 501 {
 502         walk->flags |= SKCIPHER_WALK_PHYS;
 503 
 504         INIT_LIST_HEAD(&walk->buffers);
 505 
 506         return skcipher_walk_skcipher(walk, req);
 507 }
 508 EXPORT_SYMBOL_GPL(skcipher_walk_async);
 509 
 510 static int skcipher_walk_aead_common(struct skcipher_walk *walk,
 511                                      struct aead_request *req, bool atomic)
 512 {
 513         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 514         int err;
 515 
 516         walk->nbytes = 0;
 517         walk->iv = req->iv;
 518         walk->oiv = req->iv;
 519 
 520         if (unlikely(!walk->total))
 521                 return 0;
 522 
 523         walk->flags &= ~SKCIPHER_WALK_PHYS;
 524 
 525         scatterwalk_start(&walk->in, req->src);
 526         scatterwalk_start(&walk->out, req->dst);
 527 
 528         scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
 529         scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
 530 
 531         scatterwalk_done(&walk->in, 0, walk->total);
 532         scatterwalk_done(&walk->out, 0, walk->total);
 533 
 534         if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
 535                 walk->flags |= SKCIPHER_WALK_SLEEP;
 536         else
 537                 walk->flags &= ~SKCIPHER_WALK_SLEEP;
 538 
 539         walk->blocksize = crypto_aead_blocksize(tfm);
 540         walk->stride = crypto_aead_chunksize(tfm);
 541         walk->ivsize = crypto_aead_ivsize(tfm);
 542         walk->alignmask = crypto_aead_alignmask(tfm);
 543 
 544         err = skcipher_walk_first(walk);
 545 
 546         if (atomic)
 547                 walk->flags &= ~SKCIPHER_WALK_SLEEP;
 548 
 549         return err;
 550 }
 551 
 552 int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
 553                        bool atomic)
 554 {
 555         walk->total = req->cryptlen;
 556 
 557         return skcipher_walk_aead_common(walk, req, atomic);
 558 }
 559 EXPORT_SYMBOL_GPL(skcipher_walk_aead);
 560 
 561 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
 562                                struct aead_request *req, bool atomic)
 563 {
 564         walk->total = req->cryptlen;
 565 
 566         return skcipher_walk_aead_common(walk, req, atomic);
 567 }
 568 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
 569 
 570 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
 571                                struct aead_request *req, bool atomic)
 572 {
 573         struct crypto_aead *tfm = crypto_aead_reqtfm(req);
 574 
 575         walk->total = req->cryptlen - crypto_aead_authsize(tfm);
 576 
 577         return skcipher_walk_aead_common(walk, req, atomic);
 578 }
 579 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
 580 
 581 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
 582 {
 583         if (alg->cra_type == &crypto_blkcipher_type)
 584                 return sizeof(struct crypto_blkcipher *);
 585 
 586         if (alg->cra_type == &crypto_ablkcipher_type)
 587                 return sizeof(struct crypto_ablkcipher *);
 588 
 589         return crypto_alg_extsize(alg);
 590 }
 591 
 592 static void skcipher_set_needkey(struct crypto_skcipher *tfm)
 593 {
 594         if (tfm->keysize)
 595                 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
 596 }
 597 
 598 static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
 599                                      const u8 *key, unsigned int keylen)
 600 {
 601         struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
 602         struct crypto_blkcipher *blkcipher = *ctx;
 603         int err;
 604 
 605         crypto_blkcipher_clear_flags(blkcipher, ~0);
 606         crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
 607                                               CRYPTO_TFM_REQ_MASK);
 608         err = crypto_blkcipher_setkey(blkcipher, key, keylen);
 609         crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
 610                                        CRYPTO_TFM_RES_MASK);
 611         if (unlikely(err)) {
 612                 skcipher_set_needkey(tfm);
 613                 return err;
 614         }
 615 
 616         crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 617         return 0;
 618 }
 619 
 620 static int skcipher_crypt_blkcipher(struct skcipher_request *req,
 621                                     int (*crypt)(struct blkcipher_desc *,
 622                                                  struct scatterlist *,
 623                                                  struct scatterlist *,
 624                                                  unsigned int))
 625 {
 626         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 627         struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
 628         struct blkcipher_desc desc = {
 629                 .tfm = *ctx,
 630                 .info = req->iv,
 631                 .flags = req->base.flags,
 632         };
 633 
 634 
 635         return crypt(&desc, req->dst, req->src, req->cryptlen);
 636 }
 637 
 638 static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
 639 {
 640         struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 641         struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 642         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
 643 
 644         return skcipher_crypt_blkcipher(req, alg->encrypt);
 645 }
 646 
 647 static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
 648 {
 649         struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 650         struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 651         struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
 652 
 653         return skcipher_crypt_blkcipher(req, alg->decrypt);
 654 }
 655 
 656 static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
 657 {
 658         struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
 659 
 660         crypto_free_blkcipher(*ctx);
 661 }
 662 
 663 static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
 664 {
 665         struct crypto_alg *calg = tfm->__crt_alg;
 666         struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 667         struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
 668         struct crypto_blkcipher *blkcipher;
 669         struct crypto_tfm *btfm;
 670 
 671         if (!crypto_mod_get(calg))
 672                 return -EAGAIN;
 673 
 674         btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
 675                                         CRYPTO_ALG_TYPE_MASK);
 676         if (IS_ERR(btfm)) {
 677                 crypto_mod_put(calg);
 678                 return PTR_ERR(btfm);
 679         }
 680 
 681         blkcipher = __crypto_blkcipher_cast(btfm);
 682         *ctx = blkcipher;
 683         tfm->exit = crypto_exit_skcipher_ops_blkcipher;
 684 
 685         skcipher->setkey = skcipher_setkey_blkcipher;
 686         skcipher->encrypt = skcipher_encrypt_blkcipher;
 687         skcipher->decrypt = skcipher_decrypt_blkcipher;
 688 
 689         skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
 690         skcipher->keysize = calg->cra_blkcipher.max_keysize;
 691 
 692         skcipher_set_needkey(skcipher);
 693 
 694         return 0;
 695 }
 696 
 697 static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
 698                                       const u8 *key, unsigned int keylen)
 699 {
 700         struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
 701         struct crypto_ablkcipher *ablkcipher = *ctx;
 702         int err;
 703 
 704         crypto_ablkcipher_clear_flags(ablkcipher, ~0);
 705         crypto_ablkcipher_set_flags(ablkcipher,
 706                                     crypto_skcipher_get_flags(tfm) &
 707                                     CRYPTO_TFM_REQ_MASK);
 708         err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
 709         crypto_skcipher_set_flags(tfm,
 710                                   crypto_ablkcipher_get_flags(ablkcipher) &
 711                                   CRYPTO_TFM_RES_MASK);
 712         if (unlikely(err)) {
 713                 skcipher_set_needkey(tfm);
 714                 return err;
 715         }
 716 
 717         crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 718         return 0;
 719 }
 720 
 721 static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
 722                                      int (*crypt)(struct ablkcipher_request *))
 723 {
 724         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 725         struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
 726         struct ablkcipher_request *subreq = skcipher_request_ctx(req);
 727 
 728         ablkcipher_request_set_tfm(subreq, *ctx);
 729         ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
 730                                         req->base.complete, req->base.data);
 731         ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
 732                                      req->iv);
 733 
 734         return crypt(subreq);
 735 }
 736 
 737 static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
 738 {
 739         struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 740         struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 741         struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
 742 
 743         return skcipher_crypt_ablkcipher(req, alg->encrypt);
 744 }
 745 
 746 static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
 747 {
 748         struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
 749         struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
 750         struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
 751 
 752         return skcipher_crypt_ablkcipher(req, alg->decrypt);
 753 }
 754 
 755 static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
 756 {
 757         struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
 758 
 759         crypto_free_ablkcipher(*ctx);
 760 }
 761 
 762 static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
 763 {
 764         struct crypto_alg *calg = tfm->__crt_alg;
 765         struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 766         struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
 767         struct crypto_ablkcipher *ablkcipher;
 768         struct crypto_tfm *abtfm;
 769 
 770         if (!crypto_mod_get(calg))
 771                 return -EAGAIN;
 772 
 773         abtfm = __crypto_alloc_tfm(calg, 0, 0);
 774         if (IS_ERR(abtfm)) {
 775                 crypto_mod_put(calg);
 776                 return PTR_ERR(abtfm);
 777         }
 778 
 779         ablkcipher = __crypto_ablkcipher_cast(abtfm);
 780         *ctx = ablkcipher;
 781         tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
 782 
 783         skcipher->setkey = skcipher_setkey_ablkcipher;
 784         skcipher->encrypt = skcipher_encrypt_ablkcipher;
 785         skcipher->decrypt = skcipher_decrypt_ablkcipher;
 786 
 787         skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
 788         skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
 789                             sizeof(struct ablkcipher_request);
 790         skcipher->keysize = calg->cra_ablkcipher.max_keysize;
 791 
 792         skcipher_set_needkey(skcipher);
 793 
 794         return 0;
 795 }
 796 
 797 static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
 798                                      const u8 *key, unsigned int keylen)
 799 {
 800         unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 801         struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 802         u8 *buffer, *alignbuffer;
 803         unsigned long absize;
 804         int ret;
 805 
 806         absize = keylen + alignmask;
 807         buffer = kmalloc(absize, GFP_ATOMIC);
 808         if (!buffer)
 809                 return -ENOMEM;
 810 
 811         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
 812         memcpy(alignbuffer, key, keylen);
 813         ret = cipher->setkey(tfm, alignbuffer, keylen);
 814         kzfree(buffer);
 815         return ret;
 816 }
 817 
 818 static int skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
 819                            unsigned int keylen)
 820 {
 821         struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
 822         unsigned long alignmask = crypto_skcipher_alignmask(tfm);
 823         int err;
 824 
 825         if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
 826                 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
 827                 return -EINVAL;
 828         }
 829 
 830         if ((unsigned long)key & alignmask)
 831                 err = skcipher_setkey_unaligned(tfm, key, keylen);
 832         else
 833                 err = cipher->setkey(tfm, key, keylen);
 834 
 835         if (unlikely(err)) {
 836                 skcipher_set_needkey(tfm);
 837                 return err;
 838         }
 839 
 840         crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
 841         return 0;
 842 }
 843 
 844 int crypto_skcipher_encrypt(struct skcipher_request *req)
 845 {
 846         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 847         struct crypto_alg *alg = tfm->base.__crt_alg;
 848         unsigned int cryptlen = req->cryptlen;
 849         int ret;
 850 
 851         crypto_stats_get(alg);
 852         if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 853                 ret = -ENOKEY;
 854         else
 855                 ret = tfm->encrypt(req);
 856         crypto_stats_skcipher_encrypt(cryptlen, ret, alg);
 857         return ret;
 858 }
 859 EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
 860 
 861 int crypto_skcipher_decrypt(struct skcipher_request *req)
 862 {
 863         struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 864         struct crypto_alg *alg = tfm->base.__crt_alg;
 865         unsigned int cryptlen = req->cryptlen;
 866         int ret;
 867 
 868         crypto_stats_get(alg);
 869         if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 870                 ret = -ENOKEY;
 871         else
 872                 ret = tfm->decrypt(req);
 873         crypto_stats_skcipher_decrypt(cryptlen, ret, alg);
 874         return ret;
 875 }
 876 EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
 877 
 878 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
 879 {
 880         struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 881         struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 882 
 883         alg->exit(skcipher);
 884 }
 885 
 886 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
 887 {
 888         struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
 889         struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
 890 
 891         if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
 892                 return crypto_init_skcipher_ops_blkcipher(tfm);
 893 
 894         if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type)
 895                 return crypto_init_skcipher_ops_ablkcipher(tfm);
 896 
 897         skcipher->setkey = skcipher_setkey;
 898         skcipher->encrypt = alg->encrypt;
 899         skcipher->decrypt = alg->decrypt;
 900         skcipher->ivsize = alg->ivsize;
 901         skcipher->keysize = alg->max_keysize;
 902 
 903         skcipher_set_needkey(skcipher);
 904 
 905         if (alg->exit)
 906                 skcipher->base.exit = crypto_skcipher_exit_tfm;
 907 
 908         if (alg->init)
 909                 return alg->init(skcipher);
 910 
 911         return 0;
 912 }
 913 
 914 static void crypto_skcipher_free_instance(struct crypto_instance *inst)
 915 {
 916         struct skcipher_instance *skcipher =
 917                 container_of(inst, struct skcipher_instance, s.base);
 918 
 919         skcipher->free(skcipher);
 920 }
 921 
 922 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 923         __maybe_unused;
 924 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
 925 {
 926         struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
 927                                                      base);
 928 
 929         seq_printf(m, "type         : skcipher\n");
 930         seq_printf(m, "async        : %s\n",
 931                    alg->cra_flags & CRYPTO_ALG_ASYNC ?  "yes" : "no");
 932         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
 933         seq_printf(m, "min keysize  : %u\n", skcipher->min_keysize);
 934         seq_printf(m, "max keysize  : %u\n", skcipher->max_keysize);
 935         seq_printf(m, "ivsize       : %u\n", skcipher->ivsize);
 936         seq_printf(m, "chunksize    : %u\n", skcipher->chunksize);
 937         seq_printf(m, "walksize     : %u\n", skcipher->walksize);
 938 }
 939 
 940 #ifdef CONFIG_NET
 941 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 942 {
 943         struct crypto_report_blkcipher rblkcipher;
 944         struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
 945                                                      base);
 946 
 947         memset(&rblkcipher, 0, sizeof(rblkcipher));
 948 
 949         strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
 950         strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
 951 
 952         rblkcipher.blocksize = alg->cra_blocksize;
 953         rblkcipher.min_keysize = skcipher->min_keysize;
 954         rblkcipher.max_keysize = skcipher->max_keysize;
 955         rblkcipher.ivsize = skcipher->ivsize;
 956 
 957         return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
 958                        sizeof(rblkcipher), &rblkcipher);
 959 }
 960 #else
 961 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
 962 {
 963         return -ENOSYS;
 964 }
 965 #endif
 966 
 967 static const struct crypto_type crypto_skcipher_type2 = {
 968         .extsize = crypto_skcipher_extsize,
 969         .init_tfm = crypto_skcipher_init_tfm,
 970         .free = crypto_skcipher_free_instance,
 971 #ifdef CONFIG_PROC_FS
 972         .show = crypto_skcipher_show,
 973 #endif
 974         .report = crypto_skcipher_report,
 975         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
 976         .maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
 977         .type = CRYPTO_ALG_TYPE_SKCIPHER,
 978         .tfmsize = offsetof(struct crypto_skcipher, base),
 979 };
 980 
 981 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
 982                           const char *name, u32 type, u32 mask)
 983 {
 984         spawn->base.frontend = &crypto_skcipher_type2;
 985         return crypto_grab_spawn(&spawn->base, name, type, mask);
 986 }
 987 EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
 988 
 989 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
 990                                               u32 type, u32 mask)
 991 {
 992         return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
 993 }
 994 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
 995 
 996 struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
 997                                 const char *alg_name, u32 type, u32 mask)
 998 {
 999         struct crypto_skcipher *tfm;
1000 
1001         /* Only sync algorithms allowed. */
1002         mask |= CRYPTO_ALG_ASYNC;
1003 
1004         tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
1005 
1006         /*
1007          * Make sure we do not allocate something that might get used with
1008          * an on-stack request: check the request size.
1009          */
1010         if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
1011                                     MAX_SYNC_SKCIPHER_REQSIZE)) {
1012                 crypto_free_skcipher(tfm);
1013                 return ERR_PTR(-EINVAL);
1014         }
1015 
1016         return (struct crypto_sync_skcipher *)tfm;
1017 }
1018 EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
1019 
1020 int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
1021 {
1022         return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
1023                                    type, mask);
1024 }
1025 EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
1026 
1027 static int skcipher_prepare_alg(struct skcipher_alg *alg)
1028 {
1029         struct crypto_alg *base = &alg->base;
1030 
1031         if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
1032             alg->walksize > PAGE_SIZE / 8)
1033                 return -EINVAL;
1034 
1035         if (!alg->chunksize)
1036                 alg->chunksize = base->cra_blocksize;
1037         if (!alg->walksize)
1038                 alg->walksize = alg->chunksize;
1039 
1040         base->cra_type = &crypto_skcipher_type2;
1041         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
1042         base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
1043 
1044         return 0;
1045 }
1046 
1047 int crypto_register_skcipher(struct skcipher_alg *alg)
1048 {
1049         struct crypto_alg *base = &alg->base;
1050         int err;
1051 
1052         err = skcipher_prepare_alg(alg);
1053         if (err)
1054                 return err;
1055 
1056         return crypto_register_alg(base);
1057 }
1058 EXPORT_SYMBOL_GPL(crypto_register_skcipher);
1059 
1060 void crypto_unregister_skcipher(struct skcipher_alg *alg)
1061 {
1062         crypto_unregister_alg(&alg->base);
1063 }
1064 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
1065 
1066 int crypto_register_skciphers(struct skcipher_alg *algs, int count)
1067 {
1068         int i, ret;
1069 
1070         for (i = 0; i < count; i++) {
1071                 ret = crypto_register_skcipher(&algs[i]);
1072                 if (ret)
1073                         goto err;
1074         }
1075 
1076         return 0;
1077 
1078 err:
1079         for (--i; i >= 0; --i)
1080                 crypto_unregister_skcipher(&algs[i]);
1081 
1082         return ret;
1083 }
1084 EXPORT_SYMBOL_GPL(crypto_register_skciphers);
1085 
1086 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
1087 {
1088         int i;
1089 
1090         for (i = count - 1; i >= 0; --i)
1091                 crypto_unregister_skcipher(&algs[i]);
1092 }
1093 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
1094 
1095 int skcipher_register_instance(struct crypto_template *tmpl,
1096                            struct skcipher_instance *inst)
1097 {
1098         int err;
1099 
1100         err = skcipher_prepare_alg(&inst->alg);
1101         if (err)
1102                 return err;
1103 
1104         return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
1105 }
1106 EXPORT_SYMBOL_GPL(skcipher_register_instance);
1107 
1108 static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
1109                                   unsigned int keylen)
1110 {
1111         struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
1112         int err;
1113 
1114         crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
1115         crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) &
1116                                 CRYPTO_TFM_REQ_MASK);
1117         err = crypto_cipher_setkey(cipher, key, keylen);
1118         crypto_skcipher_set_flags(tfm, crypto_cipher_get_flags(cipher) &
1119                                   CRYPTO_TFM_RES_MASK);
1120         return err;
1121 }
1122 
1123 static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
1124 {
1125         struct skcipher_instance *inst = skcipher_alg_instance(tfm);
1126         struct crypto_spawn *spawn = skcipher_instance_ctx(inst);
1127         struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1128         struct crypto_cipher *cipher;
1129 
1130         cipher = crypto_spawn_cipher(spawn);
1131         if (IS_ERR(cipher))
1132                 return PTR_ERR(cipher);
1133 
1134         ctx->cipher = cipher;
1135         return 0;
1136 }
1137 
1138 static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
1139 {
1140         struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1141 
1142         crypto_free_cipher(ctx->cipher);
1143 }
1144 
1145 static void skcipher_free_instance_simple(struct skcipher_instance *inst)
1146 {
1147         crypto_drop_spawn(skcipher_instance_ctx(inst));
1148         kfree(inst);
1149 }
1150 
1151 /**
1152  * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
1153  *
1154  * Allocate an skcipher_instance for a simple block cipher mode of operation,
1155  * e.g. cbc or ecb.  The instance context will have just a single crypto_spawn,
1156  * that for the underlying cipher.  The {min,max}_keysize, ivsize, blocksize,
1157  * alignmask, and priority are set from the underlying cipher but can be
1158  * overridden if needed.  The tfm context defaults to skcipher_ctx_simple, and
1159  * default ->setkey(), ->init(), and ->exit() methods are installed.
1160  *
1161  * @tmpl: the template being instantiated
1162  * @tb: the template parameters
1163  * @cipher_alg_ret: on success, a pointer to the underlying cipher algorithm is
1164  *                  returned here.  It must be dropped with crypto_mod_put().
1165  *
1166  * Return: a pointer to the new instance, or an ERR_PTR().  The caller still
1167  *         needs to register the instance.
1168  */
1169 struct skcipher_instance *
1170 skcipher_alloc_instance_simple(struct crypto_template *tmpl, struct rtattr **tb,
1171                                struct crypto_alg **cipher_alg_ret)
1172 {
1173         struct crypto_attr_type *algt;
1174         struct crypto_alg *cipher_alg;
1175         struct skcipher_instance *inst;
1176         struct crypto_spawn *spawn;
1177         u32 mask;
1178         int err;
1179 
1180         algt = crypto_get_attr_type(tb);
1181         if (IS_ERR(algt))
1182                 return ERR_CAST(algt);
1183 
1184         if ((algt->type ^ CRYPTO_ALG_TYPE_SKCIPHER) & algt->mask)
1185                 return ERR_PTR(-EINVAL);
1186 
1187         mask = CRYPTO_ALG_TYPE_MASK |
1188                 crypto_requires_off(algt->type, algt->mask,
1189                                     CRYPTO_ALG_NEED_FALLBACK);
1190 
1191         cipher_alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, mask);
1192         if (IS_ERR(cipher_alg))
1193                 return ERR_CAST(cipher_alg);
1194 
1195         inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
1196         if (!inst) {
1197                 err = -ENOMEM;
1198                 goto err_put_cipher_alg;
1199         }
1200         spawn = skcipher_instance_ctx(inst);
1201 
1202         err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name,
1203                                   cipher_alg);
1204         if (err)
1205                 goto err_free_inst;
1206 
1207         err = crypto_init_spawn(spawn, cipher_alg,
1208                                 skcipher_crypto_instance(inst),
1209                                 CRYPTO_ALG_TYPE_MASK);
1210         if (err)
1211                 goto err_free_inst;
1212         inst->free = skcipher_free_instance_simple;
1213 
1214         /* Default algorithm properties, can be overridden */
1215         inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1216         inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1217         inst->alg.base.cra_priority = cipher_alg->cra_priority;
1218         inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1219         inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1220         inst->alg.ivsize = cipher_alg->cra_blocksize;
1221 
1222         /* Use skcipher_ctx_simple by default, can be overridden */
1223         inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1224         inst->alg.setkey = skcipher_setkey_simple;
1225         inst->alg.init = skcipher_init_tfm_simple;
1226         inst->alg.exit = skcipher_exit_tfm_simple;
1227 
1228         *cipher_alg_ret = cipher_alg;
1229         return inst;
1230 
1231 err_free_inst:
1232         kfree(inst);
1233 err_put_cipher_alg:
1234         crypto_mod_put(cipher_alg);
1235         return ERR_PTR(err);
1236 }
1237 EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1238 
1239 MODULE_LICENSE("GPL");
1240 MODULE_DESCRIPTION("Symmetric key cipher type");