]> git.proxmox.com Git - mirror_ubuntu-bionic-kernel.git/blob - crypto/skcipher.c
Merge branch 'work.compat' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[mirror_ubuntu-bionic-kernel.git] / crypto / skcipher.c
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/compiler.h>
23 #include <linux/list.h>
24 #include <linux/module.h>
25 #include <linux/rtnetlink.h>
26 #include <linux/seq_file.h>
27 #include <net/netlink.h>
28
29 #include "internal.h"
30
31 enum {
32 SKCIPHER_WALK_PHYS = 1 << 0,
33 SKCIPHER_WALK_SLOW = 1 << 1,
34 SKCIPHER_WALK_COPY = 1 << 2,
35 SKCIPHER_WALK_DIFF = 1 << 3,
36 SKCIPHER_WALK_SLEEP = 1 << 4,
37 };
38
39 struct skcipher_walk_buffer {
40 struct list_head entry;
41 struct scatter_walk dst;
42 unsigned int len;
43 u8 *data;
44 u8 buffer[];
45 };
46
47 static int skcipher_walk_next(struct skcipher_walk *walk);
48
49 static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr)
50 {
51 if (PageHighMem(scatterwalk_page(walk)))
52 kunmap_atomic(vaddr);
53 }
54
55 static inline void *skcipher_map(struct scatter_walk *walk)
56 {
57 struct page *page = scatterwalk_page(walk);
58
59 return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) +
60 offset_in_page(walk->offset);
61 }
62
63 static inline void skcipher_map_src(struct skcipher_walk *walk)
64 {
65 walk->src.virt.addr = skcipher_map(&walk->in);
66 }
67
68 static inline void skcipher_map_dst(struct skcipher_walk *walk)
69 {
70 walk->dst.virt.addr = skcipher_map(&walk->out);
71 }
72
73 static inline void skcipher_unmap_src(struct skcipher_walk *walk)
74 {
75 skcipher_unmap(&walk->in, walk->src.virt.addr);
76 }
77
78 static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
79 {
80 skcipher_unmap(&walk->out, walk->dst.virt.addr);
81 }
82
83 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
84 {
85 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
86 }
87
88 /* Get a spot of the specified length that does not straddle a page.
89 * The caller needs to ensure that there is enough space for this operation.
90 */
91 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
92 {
93 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
94
95 return max(start, end_page);
96 }
97
98 static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
99 {
100 u8 *addr;
101
102 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
103 addr = skcipher_get_spot(addr, bsize);
104 scatterwalk_copychunks(addr, &walk->out, bsize,
105 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
106 return 0;
107 }
108
109 int skcipher_walk_done(struct skcipher_walk *walk, int err)
110 {
111 unsigned int n = walk->nbytes - err;
112 unsigned int nbytes;
113
114 nbytes = walk->total - n;
115
116 if (unlikely(err < 0)) {
117 nbytes = 0;
118 n = 0;
119 } else if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
120 SKCIPHER_WALK_SLOW |
121 SKCIPHER_WALK_COPY |
122 SKCIPHER_WALK_DIFF)))) {
123 unmap_src:
124 skcipher_unmap_src(walk);
125 } else if (walk->flags & SKCIPHER_WALK_DIFF) {
126 skcipher_unmap_dst(walk);
127 goto unmap_src;
128 } else if (walk->flags & SKCIPHER_WALK_COPY) {
129 skcipher_map_dst(walk);
130 memcpy(walk->dst.virt.addr, walk->page, n);
131 skcipher_unmap_dst(walk);
132 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
133 if (WARN_ON(err)) {
134 err = -EINVAL;
135 nbytes = 0;
136 } else
137 n = skcipher_done_slow(walk, n);
138 }
139
140 if (err > 0)
141 err = 0;
142
143 walk->total = nbytes;
144 walk->nbytes = nbytes;
145
146 scatterwalk_advance(&walk->in, n);
147 scatterwalk_advance(&walk->out, n);
148 scatterwalk_done(&walk->in, 0, nbytes);
149 scatterwalk_done(&walk->out, 1, nbytes);
150
151 if (nbytes) {
152 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
153 CRYPTO_TFM_REQ_MAY_SLEEP : 0);
154 return skcipher_walk_next(walk);
155 }
156
157 /* Short-circuit for the common/fast path. */
158 if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
159 goto out;
160
161 if (walk->flags & SKCIPHER_WALK_PHYS)
162 goto out;
163
164 if (walk->iv != walk->oiv)
165 memcpy(walk->oiv, walk->iv, walk->ivsize);
166 if (walk->buffer != walk->page)
167 kfree(walk->buffer);
168 if (walk->page)
169 free_page((unsigned long)walk->page);
170
171 out:
172 return err;
173 }
174 EXPORT_SYMBOL_GPL(skcipher_walk_done);
175
176 void skcipher_walk_complete(struct skcipher_walk *walk, int err)
177 {
178 struct skcipher_walk_buffer *p, *tmp;
179
180 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
181 u8 *data;
182
183 if (err)
184 goto done;
185
186 data = p->data;
187 if (!data) {
188 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
189 data = skcipher_get_spot(data, walk->stride);
190 }
191
192 scatterwalk_copychunks(data, &p->dst, p->len, 1);
193
194 if (offset_in_page(p->data) + p->len + walk->stride >
195 PAGE_SIZE)
196 free_page((unsigned long)p->data);
197
198 done:
199 list_del(&p->entry);
200 kfree(p);
201 }
202
203 if (!err && walk->iv != walk->oiv)
204 memcpy(walk->oiv, walk->iv, walk->ivsize);
205 if (walk->buffer != walk->page)
206 kfree(walk->buffer);
207 if (walk->page)
208 free_page((unsigned long)walk->page);
209 }
210 EXPORT_SYMBOL_GPL(skcipher_walk_complete);
211
212 static void skcipher_queue_write(struct skcipher_walk *walk,
213 struct skcipher_walk_buffer *p)
214 {
215 p->dst = walk->out;
216 list_add_tail(&p->entry, &walk->buffers);
217 }
218
219 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
220 {
221 bool phys = walk->flags & SKCIPHER_WALK_PHYS;
222 unsigned alignmask = walk->alignmask;
223 struct skcipher_walk_buffer *p;
224 unsigned a;
225 unsigned n;
226 u8 *buffer;
227 void *v;
228
229 if (!phys) {
230 if (!walk->buffer)
231 walk->buffer = walk->page;
232 buffer = walk->buffer;
233 if (buffer)
234 goto ok;
235 }
236
237 /* Start with the minimum alignment of kmalloc. */
238 a = crypto_tfm_ctx_alignment() - 1;
239 n = bsize;
240
241 if (phys) {
242 /* Calculate the minimum alignment of p->buffer. */
243 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
244 n += sizeof(*p);
245 }
246
247 /* Minimum size to align p->buffer by alignmask. */
248 n += alignmask & ~a;
249
250 /* Minimum size to ensure p->buffer does not straddle a page. */
251 n += (bsize - 1) & ~(alignmask | a);
252
253 v = kzalloc(n, skcipher_walk_gfp(walk));
254 if (!v)
255 return skcipher_walk_done(walk, -ENOMEM);
256
257 if (phys) {
258 p = v;
259 p->len = bsize;
260 skcipher_queue_write(walk, p);
261 buffer = p->buffer;
262 } else {
263 walk->buffer = v;
264 buffer = v;
265 }
266
267 ok:
268 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
269 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
270 walk->src.virt.addr = walk->dst.virt.addr;
271
272 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
273
274 walk->nbytes = bsize;
275 walk->flags |= SKCIPHER_WALK_SLOW;
276
277 return 0;
278 }
279
280 static int skcipher_next_copy(struct skcipher_walk *walk)
281 {
282 struct skcipher_walk_buffer *p;
283 u8 *tmp = walk->page;
284
285 skcipher_map_src(walk);
286 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
287 skcipher_unmap_src(walk);
288
289 walk->src.virt.addr = tmp;
290 walk->dst.virt.addr = tmp;
291
292 if (!(walk->flags & SKCIPHER_WALK_PHYS))
293 return 0;
294
295 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
296 if (!p)
297 return -ENOMEM;
298
299 p->data = walk->page;
300 p->len = walk->nbytes;
301 skcipher_queue_write(walk, p);
302
303 if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
304 PAGE_SIZE)
305 walk->page = NULL;
306 else
307 walk->page += walk->nbytes;
308
309 return 0;
310 }
311
312 static int skcipher_next_fast(struct skcipher_walk *walk)
313 {
314 unsigned long diff;
315
316 walk->src.phys.page = scatterwalk_page(&walk->in);
317 walk->src.phys.offset = offset_in_page(walk->in.offset);
318 walk->dst.phys.page = scatterwalk_page(&walk->out);
319 walk->dst.phys.offset = offset_in_page(walk->out.offset);
320
321 if (walk->flags & SKCIPHER_WALK_PHYS)
322 return 0;
323
324 diff = walk->src.phys.offset - walk->dst.phys.offset;
325 diff |= walk->src.virt.page - walk->dst.virt.page;
326
327 skcipher_map_src(walk);
328 walk->dst.virt.addr = walk->src.virt.addr;
329
330 if (diff) {
331 walk->flags |= SKCIPHER_WALK_DIFF;
332 skcipher_map_dst(walk);
333 }
334
335 return 0;
336 }
337
338 static int skcipher_walk_next(struct skcipher_walk *walk)
339 {
340 unsigned int bsize;
341 unsigned int n;
342 int err;
343
344 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
345 SKCIPHER_WALK_DIFF);
346
347 n = walk->total;
348 bsize = min(walk->stride, max(n, walk->blocksize));
349 n = scatterwalk_clamp(&walk->in, n);
350 n = scatterwalk_clamp(&walk->out, n);
351
352 if (unlikely(n < bsize)) {
353 if (unlikely(walk->total < walk->blocksize))
354 return skcipher_walk_done(walk, -EINVAL);
355
356 slow_path:
357 err = skcipher_next_slow(walk, bsize);
358 goto set_phys_lowmem;
359 }
360
361 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
362 if (!walk->page) {
363 gfp_t gfp = skcipher_walk_gfp(walk);
364
365 walk->page = (void *)__get_free_page(gfp);
366 if (!walk->page)
367 goto slow_path;
368 }
369
370 walk->nbytes = min_t(unsigned, n,
371 PAGE_SIZE - offset_in_page(walk->page));
372 walk->flags |= SKCIPHER_WALK_COPY;
373 err = skcipher_next_copy(walk);
374 goto set_phys_lowmem;
375 }
376
377 walk->nbytes = n;
378
379 return skcipher_next_fast(walk);
380
381 set_phys_lowmem:
382 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
383 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
384 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
385 walk->src.phys.offset &= PAGE_SIZE - 1;
386 walk->dst.phys.offset &= PAGE_SIZE - 1;
387 }
388 return err;
389 }
390 EXPORT_SYMBOL_GPL(skcipher_walk_next);
391
392 static int skcipher_copy_iv(struct skcipher_walk *walk)
393 {
394 unsigned a = crypto_tfm_ctx_alignment() - 1;
395 unsigned alignmask = walk->alignmask;
396 unsigned ivsize = walk->ivsize;
397 unsigned bs = walk->stride;
398 unsigned aligned_bs;
399 unsigned size;
400 u8 *iv;
401
402 aligned_bs = ALIGN(bs, alignmask);
403
404 /* Minimum size to align buffer by alignmask. */
405 size = alignmask & ~a;
406
407 if (walk->flags & SKCIPHER_WALK_PHYS)
408 size += ivsize;
409 else {
410 size += aligned_bs + ivsize;
411
412 /* Minimum size to ensure buffer does not straddle a page. */
413 size += (bs - 1) & ~(alignmask | a);
414 }
415
416 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
417 if (!walk->buffer)
418 return -ENOMEM;
419
420 iv = PTR_ALIGN(walk->buffer, alignmask + 1);
421 iv = skcipher_get_spot(iv, bs) + aligned_bs;
422
423 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
424 return 0;
425 }
426
427 static int skcipher_walk_first(struct skcipher_walk *walk)
428 {
429 walk->nbytes = 0;
430
431 if (WARN_ON_ONCE(in_irq()))
432 return -EDEADLK;
433
434 if (unlikely(!walk->total))
435 return 0;
436
437 walk->buffer = NULL;
438 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
439 int err = skcipher_copy_iv(walk);
440 if (err)
441 return err;
442 }
443
444 walk->page = NULL;
445 walk->nbytes = walk->total;
446
447 return skcipher_walk_next(walk);
448 }
449
450 static int skcipher_walk_skcipher(struct skcipher_walk *walk,
451 struct skcipher_request *req)
452 {
453 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
454
455 scatterwalk_start(&walk->in, req->src);
456 scatterwalk_start(&walk->out, req->dst);
457
458 walk->total = req->cryptlen;
459 walk->iv = req->iv;
460 walk->oiv = req->iv;
461
462 walk->flags &= ~SKCIPHER_WALK_SLEEP;
463 walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
464 SKCIPHER_WALK_SLEEP : 0;
465
466 walk->blocksize = crypto_skcipher_blocksize(tfm);
467 walk->stride = crypto_skcipher_walksize(tfm);
468 walk->ivsize = crypto_skcipher_ivsize(tfm);
469 walk->alignmask = crypto_skcipher_alignmask(tfm);
470
471 return skcipher_walk_first(walk);
472 }
473
474 int skcipher_walk_virt(struct skcipher_walk *walk,
475 struct skcipher_request *req, bool atomic)
476 {
477 int err;
478
479 walk->flags &= ~SKCIPHER_WALK_PHYS;
480
481 err = skcipher_walk_skcipher(walk, req);
482
483 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
484
485 return err;
486 }
487 EXPORT_SYMBOL_GPL(skcipher_walk_virt);
488
489 void skcipher_walk_atomise(struct skcipher_walk *walk)
490 {
491 walk->flags &= ~SKCIPHER_WALK_SLEEP;
492 }
493 EXPORT_SYMBOL_GPL(skcipher_walk_atomise);
494
495 int skcipher_walk_async(struct skcipher_walk *walk,
496 struct skcipher_request *req)
497 {
498 walk->flags |= SKCIPHER_WALK_PHYS;
499
500 INIT_LIST_HEAD(&walk->buffers);
501
502 return skcipher_walk_skcipher(walk, req);
503 }
504 EXPORT_SYMBOL_GPL(skcipher_walk_async);
505
506 static int skcipher_walk_aead_common(struct skcipher_walk *walk,
507 struct aead_request *req, bool atomic)
508 {
509 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
510 int err;
511
512 walk->flags &= ~SKCIPHER_WALK_PHYS;
513
514 scatterwalk_start(&walk->in, req->src);
515 scatterwalk_start(&walk->out, req->dst);
516
517 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
518 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
519
520 walk->iv = req->iv;
521 walk->oiv = req->iv;
522
523 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
524 walk->flags |= SKCIPHER_WALK_SLEEP;
525 else
526 walk->flags &= ~SKCIPHER_WALK_SLEEP;
527
528 walk->blocksize = crypto_aead_blocksize(tfm);
529 walk->stride = crypto_aead_chunksize(tfm);
530 walk->ivsize = crypto_aead_ivsize(tfm);
531 walk->alignmask = crypto_aead_alignmask(tfm);
532
533 err = skcipher_walk_first(walk);
534
535 if (atomic)
536 walk->flags &= ~SKCIPHER_WALK_SLEEP;
537
538 return err;
539 }
540
541 int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
542 bool atomic)
543 {
544 walk->total = req->cryptlen;
545
546 return skcipher_walk_aead_common(walk, req, atomic);
547 }
548 EXPORT_SYMBOL_GPL(skcipher_walk_aead);
549
550 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
551 struct aead_request *req, bool atomic)
552 {
553 walk->total = req->cryptlen;
554
555 return skcipher_walk_aead_common(walk, req, atomic);
556 }
557 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
558
559 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
560 struct aead_request *req, bool atomic)
561 {
562 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
563
564 walk->total = req->cryptlen - crypto_aead_authsize(tfm);
565
566 return skcipher_walk_aead_common(walk, req, atomic);
567 }
568 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
569
570 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
571 {
572 if (alg->cra_type == &crypto_blkcipher_type)
573 return sizeof(struct crypto_blkcipher *);
574
575 if (alg->cra_type == &crypto_ablkcipher_type ||
576 alg->cra_type == &crypto_givcipher_type)
577 return sizeof(struct crypto_ablkcipher *);
578
579 return crypto_alg_extsize(alg);
580 }
581
582 static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
583 const u8 *key, unsigned int keylen)
584 {
585 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
586 struct crypto_blkcipher *blkcipher = *ctx;
587 int err;
588
589 crypto_blkcipher_clear_flags(blkcipher, ~0);
590 crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
591 CRYPTO_TFM_REQ_MASK);
592 err = crypto_blkcipher_setkey(blkcipher, key, keylen);
593 crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
594 CRYPTO_TFM_RES_MASK);
595
596 return err;
597 }
598
599 static int skcipher_crypt_blkcipher(struct skcipher_request *req,
600 int (*crypt)(struct blkcipher_desc *,
601 struct scatterlist *,
602 struct scatterlist *,
603 unsigned int))
604 {
605 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
606 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
607 struct blkcipher_desc desc = {
608 .tfm = *ctx,
609 .info = req->iv,
610 .flags = req->base.flags,
611 };
612
613
614 return crypt(&desc, req->dst, req->src, req->cryptlen);
615 }
616
617 static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
618 {
619 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
620 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
621 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
622
623 return skcipher_crypt_blkcipher(req, alg->encrypt);
624 }
625
626 static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
627 {
628 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
629 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
630 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
631
632 return skcipher_crypt_blkcipher(req, alg->decrypt);
633 }
634
635 static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
636 {
637 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
638
639 crypto_free_blkcipher(*ctx);
640 }
641
642 static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
643 {
644 struct crypto_alg *calg = tfm->__crt_alg;
645 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
646 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
647 struct crypto_blkcipher *blkcipher;
648 struct crypto_tfm *btfm;
649
650 if (!crypto_mod_get(calg))
651 return -EAGAIN;
652
653 btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
654 CRYPTO_ALG_TYPE_MASK);
655 if (IS_ERR(btfm)) {
656 crypto_mod_put(calg);
657 return PTR_ERR(btfm);
658 }
659
660 blkcipher = __crypto_blkcipher_cast(btfm);
661 *ctx = blkcipher;
662 tfm->exit = crypto_exit_skcipher_ops_blkcipher;
663
664 skcipher->setkey = skcipher_setkey_blkcipher;
665 skcipher->encrypt = skcipher_encrypt_blkcipher;
666 skcipher->decrypt = skcipher_decrypt_blkcipher;
667
668 skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
669 skcipher->keysize = calg->cra_blkcipher.max_keysize;
670
671 return 0;
672 }
673
674 static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
675 const u8 *key, unsigned int keylen)
676 {
677 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
678 struct crypto_ablkcipher *ablkcipher = *ctx;
679 int err;
680
681 crypto_ablkcipher_clear_flags(ablkcipher, ~0);
682 crypto_ablkcipher_set_flags(ablkcipher,
683 crypto_skcipher_get_flags(tfm) &
684 CRYPTO_TFM_REQ_MASK);
685 err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
686 crypto_skcipher_set_flags(tfm,
687 crypto_ablkcipher_get_flags(ablkcipher) &
688 CRYPTO_TFM_RES_MASK);
689
690 return err;
691 }
692
693 static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
694 int (*crypt)(struct ablkcipher_request *))
695 {
696 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
697 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
698 struct ablkcipher_request *subreq = skcipher_request_ctx(req);
699
700 ablkcipher_request_set_tfm(subreq, *ctx);
701 ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
702 req->base.complete, req->base.data);
703 ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
704 req->iv);
705
706 return crypt(subreq);
707 }
708
709 static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
710 {
711 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
712 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
713 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
714
715 return skcipher_crypt_ablkcipher(req, alg->encrypt);
716 }
717
718 static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
719 {
720 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
721 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
722 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
723
724 return skcipher_crypt_ablkcipher(req, alg->decrypt);
725 }
726
727 static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
728 {
729 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
730
731 crypto_free_ablkcipher(*ctx);
732 }
733
734 static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
735 {
736 struct crypto_alg *calg = tfm->__crt_alg;
737 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
738 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
739 struct crypto_ablkcipher *ablkcipher;
740 struct crypto_tfm *abtfm;
741
742 if (!crypto_mod_get(calg))
743 return -EAGAIN;
744
745 abtfm = __crypto_alloc_tfm(calg, 0, 0);
746 if (IS_ERR(abtfm)) {
747 crypto_mod_put(calg);
748 return PTR_ERR(abtfm);
749 }
750
751 ablkcipher = __crypto_ablkcipher_cast(abtfm);
752 *ctx = ablkcipher;
753 tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
754
755 skcipher->setkey = skcipher_setkey_ablkcipher;
756 skcipher->encrypt = skcipher_encrypt_ablkcipher;
757 skcipher->decrypt = skcipher_decrypt_ablkcipher;
758
759 skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
760 skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
761 sizeof(struct ablkcipher_request);
762 skcipher->keysize = calg->cra_ablkcipher.max_keysize;
763
764 return 0;
765 }
766
767 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
768 {
769 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
770 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
771
772 alg->exit(skcipher);
773 }
774
775 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
776 {
777 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
778 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
779
780 if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
781 return crypto_init_skcipher_ops_blkcipher(tfm);
782
783 if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type ||
784 tfm->__crt_alg->cra_type == &crypto_givcipher_type)
785 return crypto_init_skcipher_ops_ablkcipher(tfm);
786
787 skcipher->setkey = alg->setkey;
788 skcipher->encrypt = alg->encrypt;
789 skcipher->decrypt = alg->decrypt;
790 skcipher->ivsize = alg->ivsize;
791 skcipher->keysize = alg->max_keysize;
792
793 if (alg->exit)
794 skcipher->base.exit = crypto_skcipher_exit_tfm;
795
796 if (alg->init)
797 return alg->init(skcipher);
798
799 return 0;
800 }
801
802 static void crypto_skcipher_free_instance(struct crypto_instance *inst)
803 {
804 struct skcipher_instance *skcipher =
805 container_of(inst, struct skcipher_instance, s.base);
806
807 skcipher->free(skcipher);
808 }
809
810 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
811 __maybe_unused;
812 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
813 {
814 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
815 base);
816
817 seq_printf(m, "type : skcipher\n");
818 seq_printf(m, "async : %s\n",
819 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
820 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
821 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
822 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
823 seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
824 seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
825 seq_printf(m, "walksize : %u\n", skcipher->walksize);
826 }
827
828 #ifdef CONFIG_NET
829 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
830 {
831 struct crypto_report_blkcipher rblkcipher;
832 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
833 base);
834
835 strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
836 strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
837
838 rblkcipher.blocksize = alg->cra_blocksize;
839 rblkcipher.min_keysize = skcipher->min_keysize;
840 rblkcipher.max_keysize = skcipher->max_keysize;
841 rblkcipher.ivsize = skcipher->ivsize;
842
843 if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
844 sizeof(struct crypto_report_blkcipher), &rblkcipher))
845 goto nla_put_failure;
846 return 0;
847
848 nla_put_failure:
849 return -EMSGSIZE;
850 }
851 #else
852 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
853 {
854 return -ENOSYS;
855 }
856 #endif
857
858 static const struct crypto_type crypto_skcipher_type2 = {
859 .extsize = crypto_skcipher_extsize,
860 .init_tfm = crypto_skcipher_init_tfm,
861 .free = crypto_skcipher_free_instance,
862 #ifdef CONFIG_PROC_FS
863 .show = crypto_skcipher_show,
864 #endif
865 .report = crypto_skcipher_report,
866 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
867 .maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
868 .type = CRYPTO_ALG_TYPE_SKCIPHER,
869 .tfmsize = offsetof(struct crypto_skcipher, base),
870 };
871
872 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
873 const char *name, u32 type, u32 mask)
874 {
875 spawn->base.frontend = &crypto_skcipher_type2;
876 return crypto_grab_spawn(&spawn->base, name, type, mask);
877 }
878 EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
879
880 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
881 u32 type, u32 mask)
882 {
883 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
884 }
885 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
886
887 int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
888 {
889 return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
890 type, mask);
891 }
892 EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
893
894 static int skcipher_prepare_alg(struct skcipher_alg *alg)
895 {
896 struct crypto_alg *base = &alg->base;
897
898 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
899 alg->walksize > PAGE_SIZE / 8)
900 return -EINVAL;
901
902 if (!alg->chunksize)
903 alg->chunksize = base->cra_blocksize;
904 if (!alg->walksize)
905 alg->walksize = alg->chunksize;
906
907 base->cra_type = &crypto_skcipher_type2;
908 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
909 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
910
911 return 0;
912 }
913
914 int crypto_register_skcipher(struct skcipher_alg *alg)
915 {
916 struct crypto_alg *base = &alg->base;
917 int err;
918
919 err = skcipher_prepare_alg(alg);
920 if (err)
921 return err;
922
923 return crypto_register_alg(base);
924 }
925 EXPORT_SYMBOL_GPL(crypto_register_skcipher);
926
927 void crypto_unregister_skcipher(struct skcipher_alg *alg)
928 {
929 crypto_unregister_alg(&alg->base);
930 }
931 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
932
933 int crypto_register_skciphers(struct skcipher_alg *algs, int count)
934 {
935 int i, ret;
936
937 for (i = 0; i < count; i++) {
938 ret = crypto_register_skcipher(&algs[i]);
939 if (ret)
940 goto err;
941 }
942
943 return 0;
944
945 err:
946 for (--i; i >= 0; --i)
947 crypto_unregister_skcipher(&algs[i]);
948
949 return ret;
950 }
951 EXPORT_SYMBOL_GPL(crypto_register_skciphers);
952
953 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
954 {
955 int i;
956
957 for (i = count - 1; i >= 0; --i)
958 crypto_unregister_skcipher(&algs[i]);
959 }
960 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
961
962 int skcipher_register_instance(struct crypto_template *tmpl,
963 struct skcipher_instance *inst)
964 {
965 int err;
966
967 err = skcipher_prepare_alg(&inst->alg);
968 if (err)
969 return err;
970
971 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
972 }
973 EXPORT_SYMBOL_GPL(skcipher_register_instance);
974
975 MODULE_LICENSE("GPL");
976 MODULE_DESCRIPTION("Symmetric key cipher type");