Loading...
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
31enum {
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
39struct 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
47static int skcipher_walk_next(struct skcipher_walk *walk);
48
49static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr)
50{
51 if (PageHighMem(scatterwalk_page(walk)))
52 kunmap_atomic(vaddr);
53}
54
55static 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
63static inline void skcipher_map_src(struct skcipher_walk *walk)
64{
65 walk->src.virt.addr = skcipher_map(&walk->in);
66}
67
68static inline void skcipher_map_dst(struct skcipher_walk *walk)
69{
70 walk->dst.virt.addr = skcipher_map(&walk->out);
71}
72
73static inline void skcipher_unmap_src(struct skcipher_walk *walk)
74{
75 skcipher_unmap(&walk->in, walk->src.virt.addr);
76}
77
78static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
79{
80 skcipher_unmap(&walk->out, walk->dst.virt.addr);
81}
82
83static 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 */
91static 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
98static 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
109int 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)))) {
123unmap_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
171out:
172 return err;
173}
174EXPORT_SYMBOL_GPL(skcipher_walk_done);
175
176void 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
198done:
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}
210EXPORT_SYMBOL_GPL(skcipher_walk_complete);
211
212static 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
219static 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
267ok:
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
280static 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
312static 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
338static 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
356slow_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
381set_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}
390EXPORT_SYMBOL_GPL(skcipher_walk_next);
391
392static 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
427static int skcipher_walk_first(struct skcipher_walk *walk)
428{
429 if (WARN_ON_ONCE(in_irq()))
430 return -EDEADLK;
431
432 walk->buffer = NULL;
433 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
434 int err = skcipher_copy_iv(walk);
435 if (err)
436 return err;
437 }
438
439 walk->page = NULL;
440 walk->nbytes = walk->total;
441
442 return skcipher_walk_next(walk);
443}
444
445static int skcipher_walk_skcipher(struct skcipher_walk *walk,
446 struct skcipher_request *req)
447{
448 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
449
450 walk->total = req->cryptlen;
451 walk->nbytes = 0;
452 walk->iv = req->iv;
453 walk->oiv = req->iv;
454
455 if (unlikely(!walk->total))
456 return 0;
457
458 scatterwalk_start(&walk->in, req->src);
459 scatterwalk_start(&walk->out, req->dst);
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->stride = crypto_skcipher_walksize(tfm);
467 walk->ivsize = crypto_skcipher_ivsize(tfm);
468 walk->alignmask = crypto_skcipher_alignmask(tfm);
469
470 return skcipher_walk_first(walk);
471}
472
473int 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}
486EXPORT_SYMBOL_GPL(skcipher_walk_virt);
487
488void skcipher_walk_atomise(struct skcipher_walk *walk)
489{
490 walk->flags &= ~SKCIPHER_WALK_SLEEP;
491}
492EXPORT_SYMBOL_GPL(skcipher_walk_atomise);
493
494int 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}
503EXPORT_SYMBOL_GPL(skcipher_walk_async);
504
505static int skcipher_walk_aead_common(struct skcipher_walk *walk,
506 struct aead_request *req, bool atomic)
507{
508 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
509 int err;
510
511 walk->nbytes = 0;
512 walk->iv = req->iv;
513 walk->oiv = req->iv;
514
515 if (unlikely(!walk->total))
516 return 0;
517
518 walk->flags &= ~SKCIPHER_WALK_PHYS;
519
520 scatterwalk_start(&walk->in, req->src);
521 scatterwalk_start(&walk->out, req->dst);
522
523 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
524 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
525
526 scatterwalk_done(&walk->in, 0, walk->total);
527 scatterwalk_done(&walk->out, 0, walk->total);
528
529 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
530 walk->flags |= SKCIPHER_WALK_SLEEP;
531 else
532 walk->flags &= ~SKCIPHER_WALK_SLEEP;
533
534 walk->blocksize = crypto_aead_blocksize(tfm);
535 walk->stride = crypto_aead_chunksize(tfm);
536 walk->ivsize = crypto_aead_ivsize(tfm);
537 walk->alignmask = crypto_aead_alignmask(tfm);
538
539 err = skcipher_walk_first(walk);
540
541 if (atomic)
542 walk->flags &= ~SKCIPHER_WALK_SLEEP;
543
544 return err;
545}
546
547int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
548 bool atomic)
549{
550 walk->total = req->cryptlen;
551
552 return skcipher_walk_aead_common(walk, req, atomic);
553}
554EXPORT_SYMBOL_GPL(skcipher_walk_aead);
555
556int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
557 struct aead_request *req, bool atomic)
558{
559 walk->total = req->cryptlen;
560
561 return skcipher_walk_aead_common(walk, req, atomic);
562}
563EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
564
565int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
566 struct aead_request *req, bool atomic)
567{
568 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
569
570 walk->total = req->cryptlen - crypto_aead_authsize(tfm);
571
572 return skcipher_walk_aead_common(walk, req, atomic);
573}
574EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
575
576static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
577{
578 if (alg->cra_type == &crypto_blkcipher_type)
579 return sizeof(struct crypto_blkcipher *);
580
581 if (alg->cra_type == &crypto_ablkcipher_type ||
582 alg->cra_type == &crypto_givcipher_type)
583 return sizeof(struct crypto_ablkcipher *);
584
585 return crypto_alg_extsize(alg);
586}
587
588static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
589 const u8 *key, unsigned int keylen)
590{
591 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
592 struct crypto_blkcipher *blkcipher = *ctx;
593 int err;
594
595 crypto_blkcipher_clear_flags(blkcipher, ~0);
596 crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
597 CRYPTO_TFM_REQ_MASK);
598 err = crypto_blkcipher_setkey(blkcipher, key, keylen);
599 crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
600 CRYPTO_TFM_RES_MASK);
601 if (err)
602 return err;
603
604 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
605 return 0;
606}
607
608static int skcipher_crypt_blkcipher(struct skcipher_request *req,
609 int (*crypt)(struct blkcipher_desc *,
610 struct scatterlist *,
611 struct scatterlist *,
612 unsigned int))
613{
614 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
615 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
616 struct blkcipher_desc desc = {
617 .tfm = *ctx,
618 .info = req->iv,
619 .flags = req->base.flags,
620 };
621
622
623 return crypt(&desc, req->dst, req->src, req->cryptlen);
624}
625
626static int skcipher_encrypt_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->encrypt);
633}
634
635static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
636{
637 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
638 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
639 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
640
641 return skcipher_crypt_blkcipher(req, alg->decrypt);
642}
643
644static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
645{
646 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
647
648 crypto_free_blkcipher(*ctx);
649}
650
651static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
652{
653 struct crypto_alg *calg = tfm->__crt_alg;
654 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
655 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
656 struct crypto_blkcipher *blkcipher;
657 struct crypto_tfm *btfm;
658
659 if (!crypto_mod_get(calg))
660 return -EAGAIN;
661
662 btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
663 CRYPTO_ALG_TYPE_MASK);
664 if (IS_ERR(btfm)) {
665 crypto_mod_put(calg);
666 return PTR_ERR(btfm);
667 }
668
669 blkcipher = __crypto_blkcipher_cast(btfm);
670 *ctx = blkcipher;
671 tfm->exit = crypto_exit_skcipher_ops_blkcipher;
672
673 skcipher->setkey = skcipher_setkey_blkcipher;
674 skcipher->encrypt = skcipher_encrypt_blkcipher;
675 skcipher->decrypt = skcipher_decrypt_blkcipher;
676
677 skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
678 skcipher->keysize = calg->cra_blkcipher.max_keysize;
679
680 if (skcipher->keysize)
681 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
682
683 return 0;
684}
685
686static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
687 const u8 *key, unsigned int keylen)
688{
689 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
690 struct crypto_ablkcipher *ablkcipher = *ctx;
691 int err;
692
693 crypto_ablkcipher_clear_flags(ablkcipher, ~0);
694 crypto_ablkcipher_set_flags(ablkcipher,
695 crypto_skcipher_get_flags(tfm) &
696 CRYPTO_TFM_REQ_MASK);
697 err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
698 crypto_skcipher_set_flags(tfm,
699 crypto_ablkcipher_get_flags(ablkcipher) &
700 CRYPTO_TFM_RES_MASK);
701 if (err)
702 return err;
703
704 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
705 return 0;
706}
707
708static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
709 int (*crypt)(struct ablkcipher_request *))
710{
711 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
712 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
713 struct ablkcipher_request *subreq = skcipher_request_ctx(req);
714
715 ablkcipher_request_set_tfm(subreq, *ctx);
716 ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
717 req->base.complete, req->base.data);
718 ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
719 req->iv);
720
721 return crypt(subreq);
722}
723
724static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
725{
726 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
727 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
728 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
729
730 return skcipher_crypt_ablkcipher(req, alg->encrypt);
731}
732
733static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
734{
735 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
736 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
737 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
738
739 return skcipher_crypt_ablkcipher(req, alg->decrypt);
740}
741
742static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
743{
744 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
745
746 crypto_free_ablkcipher(*ctx);
747}
748
749static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
750{
751 struct crypto_alg *calg = tfm->__crt_alg;
752 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
753 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
754 struct crypto_ablkcipher *ablkcipher;
755 struct crypto_tfm *abtfm;
756
757 if (!crypto_mod_get(calg))
758 return -EAGAIN;
759
760 abtfm = __crypto_alloc_tfm(calg, 0, 0);
761 if (IS_ERR(abtfm)) {
762 crypto_mod_put(calg);
763 return PTR_ERR(abtfm);
764 }
765
766 ablkcipher = __crypto_ablkcipher_cast(abtfm);
767 *ctx = ablkcipher;
768 tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
769
770 skcipher->setkey = skcipher_setkey_ablkcipher;
771 skcipher->encrypt = skcipher_encrypt_ablkcipher;
772 skcipher->decrypt = skcipher_decrypt_ablkcipher;
773
774 skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
775 skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
776 sizeof(struct ablkcipher_request);
777 skcipher->keysize = calg->cra_ablkcipher.max_keysize;
778
779 if (skcipher->keysize)
780 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
781
782 return 0;
783}
784
785static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
786 const u8 *key, unsigned int keylen)
787{
788 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
789 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
790 u8 *buffer, *alignbuffer;
791 unsigned long absize;
792 int ret;
793
794 absize = keylen + alignmask;
795 buffer = kmalloc(absize, GFP_ATOMIC);
796 if (!buffer)
797 return -ENOMEM;
798
799 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
800 memcpy(alignbuffer, key, keylen);
801 ret = cipher->setkey(tfm, alignbuffer, keylen);
802 kzfree(buffer);
803 return ret;
804}
805
806static int skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
807 unsigned int keylen)
808{
809 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
810 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
811 int err;
812
813 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
814 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
815 return -EINVAL;
816 }
817
818 if ((unsigned long)key & alignmask)
819 err = skcipher_setkey_unaligned(tfm, key, keylen);
820 else
821 err = cipher->setkey(tfm, key, keylen);
822
823 if (err)
824 return err;
825
826 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
827 return 0;
828}
829
830static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
831{
832 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
833 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
834
835 alg->exit(skcipher);
836}
837
838static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
839{
840 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
841 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
842
843 if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
844 return crypto_init_skcipher_ops_blkcipher(tfm);
845
846 if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type ||
847 tfm->__crt_alg->cra_type == &crypto_givcipher_type)
848 return crypto_init_skcipher_ops_ablkcipher(tfm);
849
850 skcipher->setkey = skcipher_setkey;
851 skcipher->encrypt = alg->encrypt;
852 skcipher->decrypt = alg->decrypt;
853 skcipher->ivsize = alg->ivsize;
854 skcipher->keysize = alg->max_keysize;
855
856 if (skcipher->keysize)
857 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
858
859 if (alg->exit)
860 skcipher->base.exit = crypto_skcipher_exit_tfm;
861
862 if (alg->init)
863 return alg->init(skcipher);
864
865 return 0;
866}
867
868static void crypto_skcipher_free_instance(struct crypto_instance *inst)
869{
870 struct skcipher_instance *skcipher =
871 container_of(inst, struct skcipher_instance, s.base);
872
873 skcipher->free(skcipher);
874}
875
876static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
877 __maybe_unused;
878static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
879{
880 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
881 base);
882
883 seq_printf(m, "type : skcipher\n");
884 seq_printf(m, "async : %s\n",
885 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
886 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
887 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
888 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
889 seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
890 seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
891 seq_printf(m, "walksize : %u\n", skcipher->walksize);
892}
893
894#ifdef CONFIG_NET
895static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
896{
897 struct crypto_report_blkcipher rblkcipher;
898 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
899 base);
900
901 strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
902 strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
903
904 rblkcipher.blocksize = alg->cra_blocksize;
905 rblkcipher.min_keysize = skcipher->min_keysize;
906 rblkcipher.max_keysize = skcipher->max_keysize;
907 rblkcipher.ivsize = skcipher->ivsize;
908
909 if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
910 sizeof(struct crypto_report_blkcipher), &rblkcipher))
911 goto nla_put_failure;
912 return 0;
913
914nla_put_failure:
915 return -EMSGSIZE;
916}
917#else
918static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
919{
920 return -ENOSYS;
921}
922#endif
923
924static const struct crypto_type crypto_skcipher_type2 = {
925 .extsize = crypto_skcipher_extsize,
926 .init_tfm = crypto_skcipher_init_tfm,
927 .free = crypto_skcipher_free_instance,
928#ifdef CONFIG_PROC_FS
929 .show = crypto_skcipher_show,
930#endif
931 .report = crypto_skcipher_report,
932 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
933 .maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
934 .type = CRYPTO_ALG_TYPE_SKCIPHER,
935 .tfmsize = offsetof(struct crypto_skcipher, base),
936};
937
938int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
939 const char *name, u32 type, u32 mask)
940{
941 spawn->base.frontend = &crypto_skcipher_type2;
942 return crypto_grab_spawn(&spawn->base, name, type, mask);
943}
944EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
945
946struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
947 u32 type, u32 mask)
948{
949 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
950}
951EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
952
953int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
954{
955 return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
956 type, mask);
957}
958EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
959
960static int skcipher_prepare_alg(struct skcipher_alg *alg)
961{
962 struct crypto_alg *base = &alg->base;
963
964 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
965 alg->walksize > PAGE_SIZE / 8)
966 return -EINVAL;
967
968 if (!alg->chunksize)
969 alg->chunksize = base->cra_blocksize;
970 if (!alg->walksize)
971 alg->walksize = alg->chunksize;
972
973 base->cra_type = &crypto_skcipher_type2;
974 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
975 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
976
977 return 0;
978}
979
980int crypto_register_skcipher(struct skcipher_alg *alg)
981{
982 struct crypto_alg *base = &alg->base;
983 int err;
984
985 err = skcipher_prepare_alg(alg);
986 if (err)
987 return err;
988
989 return crypto_register_alg(base);
990}
991EXPORT_SYMBOL_GPL(crypto_register_skcipher);
992
993void crypto_unregister_skcipher(struct skcipher_alg *alg)
994{
995 crypto_unregister_alg(&alg->base);
996}
997EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
998
999int crypto_register_skciphers(struct skcipher_alg *algs, int count)
1000{
1001 int i, ret;
1002
1003 for (i = 0; i < count; i++) {
1004 ret = crypto_register_skcipher(&algs[i]);
1005 if (ret)
1006 goto err;
1007 }
1008
1009 return 0;
1010
1011err:
1012 for (--i; i >= 0; --i)
1013 crypto_unregister_skcipher(&algs[i]);
1014
1015 return ret;
1016}
1017EXPORT_SYMBOL_GPL(crypto_register_skciphers);
1018
1019void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
1020{
1021 int i;
1022
1023 for (i = count - 1; i >= 0; --i)
1024 crypto_unregister_skcipher(&algs[i]);
1025}
1026EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
1027
1028int skcipher_register_instance(struct crypto_template *tmpl,
1029 struct skcipher_instance *inst)
1030{
1031 int err;
1032
1033 err = skcipher_prepare_alg(&inst->alg);
1034 if (err)
1035 return err;
1036
1037 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
1038}
1039EXPORT_SYMBOL_GPL(skcipher_register_instance);
1040
1041MODULE_LICENSE("GPL");
1042MODULE_DESCRIPTION("Symmetric key cipher type");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Symmetric key cipher operations.
4 *
5 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
6 * multiple page boundaries by using temporary blocks. In user context,
7 * the kernel is given a chance to schedule us once per page.
8 *
9 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
10 */
11
12#include <crypto/internal/aead.h>
13#include <crypto/internal/cipher.h>
14#include <crypto/internal/skcipher.h>
15#include <crypto/scatterwalk.h>
16#include <linux/bug.h>
17#include <linux/cryptouser.h>
18#include <linux/err.h>
19#include <linux/kernel.h>
20#include <linux/list.h>
21#include <linux/mm.h>
22#include <linux/module.h>
23#include <linux/seq_file.h>
24#include <linux/slab.h>
25#include <linux/string.h>
26#include <net/netlink.h>
27#include "skcipher.h"
28
29#define CRYPTO_ALG_TYPE_SKCIPHER_MASK 0x0000000e
30
31enum {
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
39struct 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
47static const struct crypto_type crypto_skcipher_type;
48
49static int skcipher_walk_next(struct skcipher_walk *walk);
50
51static inline void skcipher_map_src(struct skcipher_walk *walk)
52{
53 walk->src.virt.addr = scatterwalk_map(&walk->in);
54}
55
56static inline void skcipher_map_dst(struct skcipher_walk *walk)
57{
58 walk->dst.virt.addr = scatterwalk_map(&walk->out);
59}
60
61static inline void skcipher_unmap_src(struct skcipher_walk *walk)
62{
63 scatterwalk_unmap(walk->src.virt.addr);
64}
65
66static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
67{
68 scatterwalk_unmap(walk->dst.virt.addr);
69}
70
71static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
72{
73 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
74}
75
76/* Get a spot of the specified length that does not straddle a page.
77 * The caller needs to ensure that there is enough space for this operation.
78 */
79static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
80{
81 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
82
83 return max(start, end_page);
84}
85
86static inline struct skcipher_alg *__crypto_skcipher_alg(
87 struct crypto_alg *alg)
88{
89 return container_of(alg, struct skcipher_alg, base);
90}
91
92static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
93{
94 u8 *addr;
95
96 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
97 addr = skcipher_get_spot(addr, bsize);
98 scatterwalk_copychunks(addr, &walk->out, bsize,
99 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
100 return 0;
101}
102
103int skcipher_walk_done(struct skcipher_walk *walk, int err)
104{
105 unsigned int n = walk->nbytes;
106 unsigned int nbytes = 0;
107
108 if (!n)
109 goto finish;
110
111 if (likely(err >= 0)) {
112 n -= err;
113 nbytes = walk->total - n;
114 }
115
116 if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
117 SKCIPHER_WALK_SLOW |
118 SKCIPHER_WALK_COPY |
119 SKCIPHER_WALK_DIFF)))) {
120unmap_src:
121 skcipher_unmap_src(walk);
122 } else if (walk->flags & SKCIPHER_WALK_DIFF) {
123 skcipher_unmap_dst(walk);
124 goto unmap_src;
125 } else if (walk->flags & SKCIPHER_WALK_COPY) {
126 skcipher_map_dst(walk);
127 memcpy(walk->dst.virt.addr, walk->page, n);
128 skcipher_unmap_dst(walk);
129 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
130 if (err > 0) {
131 /*
132 * Didn't process all bytes. Either the algorithm is
133 * broken, or this was the last step and it turned out
134 * the message wasn't evenly divisible into blocks but
135 * the algorithm requires it.
136 */
137 err = -EINVAL;
138 nbytes = 0;
139 } else
140 n = skcipher_done_slow(walk, n);
141 }
142
143 if (err > 0)
144 err = 0;
145
146 walk->total = nbytes;
147 walk->nbytes = 0;
148
149 scatterwalk_advance(&walk->in, n);
150 scatterwalk_advance(&walk->out, n);
151 scatterwalk_done(&walk->in, 0, nbytes);
152 scatterwalk_done(&walk->out, 1, nbytes);
153
154 if (nbytes) {
155 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
156 CRYPTO_TFM_REQ_MAY_SLEEP : 0);
157 return skcipher_walk_next(walk);
158 }
159
160finish:
161 /* Short-circuit for the common/fast path. */
162 if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
163 goto out;
164
165 if (walk->flags & SKCIPHER_WALK_PHYS)
166 goto out;
167
168 if (walk->iv != walk->oiv)
169 memcpy(walk->oiv, walk->iv, walk->ivsize);
170 if (walk->buffer != walk->page)
171 kfree(walk->buffer);
172 if (walk->page)
173 free_page((unsigned long)walk->page);
174
175out:
176 return err;
177}
178EXPORT_SYMBOL_GPL(skcipher_walk_done);
179
180void skcipher_walk_complete(struct skcipher_walk *walk, int err)
181{
182 struct skcipher_walk_buffer *p, *tmp;
183
184 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
185 u8 *data;
186
187 if (err)
188 goto done;
189
190 data = p->data;
191 if (!data) {
192 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
193 data = skcipher_get_spot(data, walk->stride);
194 }
195
196 scatterwalk_copychunks(data, &p->dst, p->len, 1);
197
198 if (offset_in_page(p->data) + p->len + walk->stride >
199 PAGE_SIZE)
200 free_page((unsigned long)p->data);
201
202done:
203 list_del(&p->entry);
204 kfree(p);
205 }
206
207 if (!err && walk->iv != walk->oiv)
208 memcpy(walk->oiv, walk->iv, walk->ivsize);
209 if (walk->buffer != walk->page)
210 kfree(walk->buffer);
211 if (walk->page)
212 free_page((unsigned long)walk->page);
213}
214EXPORT_SYMBOL_GPL(skcipher_walk_complete);
215
216static void skcipher_queue_write(struct skcipher_walk *walk,
217 struct skcipher_walk_buffer *p)
218{
219 p->dst = walk->out;
220 list_add_tail(&p->entry, &walk->buffers);
221}
222
223static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
224{
225 bool phys = walk->flags & SKCIPHER_WALK_PHYS;
226 unsigned alignmask = walk->alignmask;
227 struct skcipher_walk_buffer *p;
228 unsigned a;
229 unsigned n;
230 u8 *buffer;
231 void *v;
232
233 if (!phys) {
234 if (!walk->buffer)
235 walk->buffer = walk->page;
236 buffer = walk->buffer;
237 if (buffer)
238 goto ok;
239 }
240
241 /* Start with the minimum alignment of kmalloc. */
242 a = crypto_tfm_ctx_alignment() - 1;
243 n = bsize;
244
245 if (phys) {
246 /* Calculate the minimum alignment of p->buffer. */
247 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
248 n += sizeof(*p);
249 }
250
251 /* Minimum size to align p->buffer by alignmask. */
252 n += alignmask & ~a;
253
254 /* Minimum size to ensure p->buffer does not straddle a page. */
255 n += (bsize - 1) & ~(alignmask | a);
256
257 v = kzalloc(n, skcipher_walk_gfp(walk));
258 if (!v)
259 return skcipher_walk_done(walk, -ENOMEM);
260
261 if (phys) {
262 p = v;
263 p->len = bsize;
264 skcipher_queue_write(walk, p);
265 buffer = p->buffer;
266 } else {
267 walk->buffer = v;
268 buffer = v;
269 }
270
271ok:
272 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
273 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
274 walk->src.virt.addr = walk->dst.virt.addr;
275
276 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
277
278 walk->nbytes = bsize;
279 walk->flags |= SKCIPHER_WALK_SLOW;
280
281 return 0;
282}
283
284static int skcipher_next_copy(struct skcipher_walk *walk)
285{
286 struct skcipher_walk_buffer *p;
287 u8 *tmp = walk->page;
288
289 skcipher_map_src(walk);
290 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
291 skcipher_unmap_src(walk);
292
293 walk->src.virt.addr = tmp;
294 walk->dst.virt.addr = tmp;
295
296 if (!(walk->flags & SKCIPHER_WALK_PHYS))
297 return 0;
298
299 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
300 if (!p)
301 return -ENOMEM;
302
303 p->data = walk->page;
304 p->len = walk->nbytes;
305 skcipher_queue_write(walk, p);
306
307 if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
308 PAGE_SIZE)
309 walk->page = NULL;
310 else
311 walk->page += walk->nbytes;
312
313 return 0;
314}
315
316static int skcipher_next_fast(struct skcipher_walk *walk)
317{
318 unsigned long diff;
319
320 walk->src.phys.page = scatterwalk_page(&walk->in);
321 walk->src.phys.offset = offset_in_page(walk->in.offset);
322 walk->dst.phys.page = scatterwalk_page(&walk->out);
323 walk->dst.phys.offset = offset_in_page(walk->out.offset);
324
325 if (walk->flags & SKCIPHER_WALK_PHYS)
326 return 0;
327
328 diff = walk->src.phys.offset - walk->dst.phys.offset;
329 diff |= walk->src.virt.page - walk->dst.virt.page;
330
331 skcipher_map_src(walk);
332 walk->dst.virt.addr = walk->src.virt.addr;
333
334 if (diff) {
335 walk->flags |= SKCIPHER_WALK_DIFF;
336 skcipher_map_dst(walk);
337 }
338
339 return 0;
340}
341
342static int skcipher_walk_next(struct skcipher_walk *walk)
343{
344 unsigned int bsize;
345 unsigned int n;
346 int err;
347
348 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
349 SKCIPHER_WALK_DIFF);
350
351 n = walk->total;
352 bsize = min(walk->stride, max(n, walk->blocksize));
353 n = scatterwalk_clamp(&walk->in, n);
354 n = scatterwalk_clamp(&walk->out, n);
355
356 if (unlikely(n < bsize)) {
357 if (unlikely(walk->total < walk->blocksize))
358 return skcipher_walk_done(walk, -EINVAL);
359
360slow_path:
361 err = skcipher_next_slow(walk, bsize);
362 goto set_phys_lowmem;
363 }
364
365 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
366 if (!walk->page) {
367 gfp_t gfp = skcipher_walk_gfp(walk);
368
369 walk->page = (void *)__get_free_page(gfp);
370 if (!walk->page)
371 goto slow_path;
372 }
373
374 walk->nbytes = min_t(unsigned, n,
375 PAGE_SIZE - offset_in_page(walk->page));
376 walk->flags |= SKCIPHER_WALK_COPY;
377 err = skcipher_next_copy(walk);
378 goto set_phys_lowmem;
379 }
380
381 walk->nbytes = n;
382
383 return skcipher_next_fast(walk);
384
385set_phys_lowmem:
386 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
387 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
388 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
389 walk->src.phys.offset &= PAGE_SIZE - 1;
390 walk->dst.phys.offset &= PAGE_SIZE - 1;
391 }
392 return err;
393}
394
395static int skcipher_copy_iv(struct skcipher_walk *walk)
396{
397 unsigned a = crypto_tfm_ctx_alignment() - 1;
398 unsigned alignmask = walk->alignmask;
399 unsigned ivsize = walk->ivsize;
400 unsigned bs = walk->stride;
401 unsigned aligned_bs;
402 unsigned size;
403 u8 *iv;
404
405 aligned_bs = ALIGN(bs, alignmask + 1);
406
407 /* Minimum size to align buffer by alignmask. */
408 size = alignmask & ~a;
409
410 if (walk->flags & SKCIPHER_WALK_PHYS)
411 size += ivsize;
412 else {
413 size += aligned_bs + ivsize;
414
415 /* Minimum size to ensure buffer does not straddle a page. */
416 size += (bs - 1) & ~(alignmask | a);
417 }
418
419 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
420 if (!walk->buffer)
421 return -ENOMEM;
422
423 iv = PTR_ALIGN(walk->buffer, alignmask + 1);
424 iv = skcipher_get_spot(iv, bs) + aligned_bs;
425
426 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
427 return 0;
428}
429
430static int skcipher_walk_first(struct skcipher_walk *walk)
431{
432 if (WARN_ON_ONCE(in_hardirq()))
433 return -EDEADLK;
434
435 walk->buffer = NULL;
436 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
437 int err = skcipher_copy_iv(walk);
438 if (err)
439 return err;
440 }
441
442 walk->page = NULL;
443
444 return skcipher_walk_next(walk);
445}
446
447static int skcipher_walk_skcipher(struct skcipher_walk *walk,
448 struct skcipher_request *req)
449{
450 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
451 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
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->ivsize = crypto_skcipher_ivsize(tfm);
470 walk->alignmask = crypto_skcipher_alignmask(tfm);
471
472 if (alg->co.base.cra_type != &crypto_skcipher_type)
473 walk->stride = alg->co.chunksize;
474 else
475 walk->stride = alg->walksize;
476
477 return skcipher_walk_first(walk);
478}
479
480int skcipher_walk_virt(struct skcipher_walk *walk,
481 struct skcipher_request *req, bool atomic)
482{
483 int err;
484
485 might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
486
487 walk->flags &= ~SKCIPHER_WALK_PHYS;
488
489 err = skcipher_walk_skcipher(walk, req);
490
491 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
492
493 return err;
494}
495EXPORT_SYMBOL_GPL(skcipher_walk_virt);
496
497int skcipher_walk_async(struct skcipher_walk *walk,
498 struct skcipher_request *req)
499{
500 walk->flags |= SKCIPHER_WALK_PHYS;
501
502 INIT_LIST_HEAD(&walk->buffers);
503
504 return skcipher_walk_skcipher(walk, req);
505}
506EXPORT_SYMBOL_GPL(skcipher_walk_async);
507
508static int skcipher_walk_aead_common(struct skcipher_walk *walk,
509 struct aead_request *req, bool atomic)
510{
511 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
512 int err;
513
514 walk->nbytes = 0;
515 walk->iv = req->iv;
516 walk->oiv = req->iv;
517
518 if (unlikely(!walk->total))
519 return 0;
520
521 walk->flags &= ~SKCIPHER_WALK_PHYS;
522
523 scatterwalk_start(&walk->in, req->src);
524 scatterwalk_start(&walk->out, req->dst);
525
526 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
527 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
528
529 scatterwalk_done(&walk->in, 0, walk->total);
530 scatterwalk_done(&walk->out, 0, walk->total);
531
532 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
533 walk->flags |= SKCIPHER_WALK_SLEEP;
534 else
535 walk->flags &= ~SKCIPHER_WALK_SLEEP;
536
537 walk->blocksize = crypto_aead_blocksize(tfm);
538 walk->stride = crypto_aead_chunksize(tfm);
539 walk->ivsize = crypto_aead_ivsize(tfm);
540 walk->alignmask = crypto_aead_alignmask(tfm);
541
542 err = skcipher_walk_first(walk);
543
544 if (atomic)
545 walk->flags &= ~SKCIPHER_WALK_SLEEP;
546
547 return err;
548}
549
550int 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}
557EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
558
559int 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}
568EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
569
570static void skcipher_set_needkey(struct crypto_skcipher *tfm)
571{
572 if (crypto_skcipher_max_keysize(tfm) != 0)
573 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
574}
575
576static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
577 const u8 *key, unsigned int keylen)
578{
579 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
580 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
581 u8 *buffer, *alignbuffer;
582 unsigned long absize;
583 int ret;
584
585 absize = keylen + alignmask;
586 buffer = kmalloc(absize, GFP_ATOMIC);
587 if (!buffer)
588 return -ENOMEM;
589
590 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
591 memcpy(alignbuffer, key, keylen);
592 ret = cipher->setkey(tfm, alignbuffer, keylen);
593 kfree_sensitive(buffer);
594 return ret;
595}
596
597int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
598 unsigned int keylen)
599{
600 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
601 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
602 int err;
603
604 if (cipher->co.base.cra_type != &crypto_skcipher_type) {
605 struct crypto_lskcipher **ctx = crypto_skcipher_ctx(tfm);
606
607 crypto_lskcipher_clear_flags(*ctx, CRYPTO_TFM_REQ_MASK);
608 crypto_lskcipher_set_flags(*ctx,
609 crypto_skcipher_get_flags(tfm) &
610 CRYPTO_TFM_REQ_MASK);
611 err = crypto_lskcipher_setkey(*ctx, key, keylen);
612 goto out;
613 }
614
615 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize)
616 return -EINVAL;
617
618 if ((unsigned long)key & alignmask)
619 err = skcipher_setkey_unaligned(tfm, key, keylen);
620 else
621 err = cipher->setkey(tfm, key, keylen);
622
623out:
624 if (unlikely(err)) {
625 skcipher_set_needkey(tfm);
626 return err;
627 }
628
629 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
630 return 0;
631}
632EXPORT_SYMBOL_GPL(crypto_skcipher_setkey);
633
634int crypto_skcipher_encrypt(struct skcipher_request *req)
635{
636 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
637 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
638
639 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
640 return -ENOKEY;
641 if (alg->co.base.cra_type != &crypto_skcipher_type)
642 return crypto_lskcipher_encrypt_sg(req);
643 return alg->encrypt(req);
644}
645EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
646
647int crypto_skcipher_decrypt(struct skcipher_request *req)
648{
649 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
650 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
651
652 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
653 return -ENOKEY;
654 if (alg->co.base.cra_type != &crypto_skcipher_type)
655 return crypto_lskcipher_decrypt_sg(req);
656 return alg->decrypt(req);
657}
658EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
659
660static int crypto_lskcipher_export(struct skcipher_request *req, void *out)
661{
662 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
663 u8 *ivs = skcipher_request_ctx(req);
664
665 ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
666
667 memcpy(out, ivs + crypto_skcipher_ivsize(tfm),
668 crypto_skcipher_statesize(tfm));
669
670 return 0;
671}
672
673static int crypto_lskcipher_import(struct skcipher_request *req, const void *in)
674{
675 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
676 u8 *ivs = skcipher_request_ctx(req);
677
678 ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
679
680 memcpy(ivs + crypto_skcipher_ivsize(tfm), in,
681 crypto_skcipher_statesize(tfm));
682
683 return 0;
684}
685
686static int skcipher_noexport(struct skcipher_request *req, void *out)
687{
688 return 0;
689}
690
691static int skcipher_noimport(struct skcipher_request *req, const void *in)
692{
693 return 0;
694}
695
696int crypto_skcipher_export(struct skcipher_request *req, void *out)
697{
698 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
699 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
700
701 if (alg->co.base.cra_type != &crypto_skcipher_type)
702 return crypto_lskcipher_export(req, out);
703 return alg->export(req, out);
704}
705EXPORT_SYMBOL_GPL(crypto_skcipher_export);
706
707int crypto_skcipher_import(struct skcipher_request *req, const void *in)
708{
709 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
710 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
711
712 if (alg->co.base.cra_type != &crypto_skcipher_type)
713 return crypto_lskcipher_import(req, in);
714 return alg->import(req, in);
715}
716EXPORT_SYMBOL_GPL(crypto_skcipher_import);
717
718static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
719{
720 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
721 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
722
723 alg->exit(skcipher);
724}
725
726static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
727{
728 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
729 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
730
731 skcipher_set_needkey(skcipher);
732
733 if (tfm->__crt_alg->cra_type != &crypto_skcipher_type) {
734 unsigned am = crypto_skcipher_alignmask(skcipher);
735 unsigned reqsize;
736
737 reqsize = am & ~(crypto_tfm_ctx_alignment() - 1);
738 reqsize += crypto_skcipher_ivsize(skcipher);
739 reqsize += crypto_skcipher_statesize(skcipher);
740 crypto_skcipher_set_reqsize(skcipher, reqsize);
741
742 return crypto_init_lskcipher_ops_sg(tfm);
743 }
744
745 if (alg->exit)
746 skcipher->base.exit = crypto_skcipher_exit_tfm;
747
748 if (alg->init)
749 return alg->init(skcipher);
750
751 return 0;
752}
753
754static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
755{
756 if (alg->cra_type != &crypto_skcipher_type)
757 return sizeof(struct crypto_lskcipher *);
758
759 return crypto_alg_extsize(alg);
760}
761
762static void crypto_skcipher_free_instance(struct crypto_instance *inst)
763{
764 struct skcipher_instance *skcipher =
765 container_of(inst, struct skcipher_instance, s.base);
766
767 skcipher->free(skcipher);
768}
769
770static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
771 __maybe_unused;
772static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
773{
774 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
775
776 seq_printf(m, "type : skcipher\n");
777 seq_printf(m, "async : %s\n",
778 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
779 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
780 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
781 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
782 seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
783 seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
784 seq_printf(m, "walksize : %u\n", skcipher->walksize);
785 seq_printf(m, "statesize : %u\n", skcipher->statesize);
786}
787
788static int __maybe_unused crypto_skcipher_report(
789 struct sk_buff *skb, struct crypto_alg *alg)
790{
791 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
792 struct crypto_report_blkcipher rblkcipher;
793
794 memset(&rblkcipher, 0, sizeof(rblkcipher));
795
796 strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
797 strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
798
799 rblkcipher.blocksize = alg->cra_blocksize;
800 rblkcipher.min_keysize = skcipher->min_keysize;
801 rblkcipher.max_keysize = skcipher->max_keysize;
802 rblkcipher.ivsize = skcipher->ivsize;
803
804 return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
805 sizeof(rblkcipher), &rblkcipher);
806}
807
808static const struct crypto_type crypto_skcipher_type = {
809 .extsize = crypto_skcipher_extsize,
810 .init_tfm = crypto_skcipher_init_tfm,
811 .free = crypto_skcipher_free_instance,
812#ifdef CONFIG_PROC_FS
813 .show = crypto_skcipher_show,
814#endif
815#if IS_ENABLED(CONFIG_CRYPTO_USER)
816 .report = crypto_skcipher_report,
817#endif
818 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
819 .maskset = CRYPTO_ALG_TYPE_SKCIPHER_MASK,
820 .type = CRYPTO_ALG_TYPE_SKCIPHER,
821 .tfmsize = offsetof(struct crypto_skcipher, base),
822};
823
824int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
825 struct crypto_instance *inst,
826 const char *name, u32 type, u32 mask)
827{
828 spawn->base.frontend = &crypto_skcipher_type;
829 return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
830}
831EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
832
833struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
834 u32 type, u32 mask)
835{
836 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
837}
838EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
839
840struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
841 const char *alg_name, u32 type, u32 mask)
842{
843 struct crypto_skcipher *tfm;
844
845 /* Only sync algorithms allowed. */
846 mask |= CRYPTO_ALG_ASYNC | CRYPTO_ALG_SKCIPHER_REQSIZE_LARGE;
847
848 tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
849
850 /*
851 * Make sure we do not allocate something that might get used with
852 * an on-stack request: check the request size.
853 */
854 if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
855 MAX_SYNC_SKCIPHER_REQSIZE)) {
856 crypto_free_skcipher(tfm);
857 return ERR_PTR(-EINVAL);
858 }
859
860 return (struct crypto_sync_skcipher *)tfm;
861}
862EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
863
864int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask)
865{
866 return crypto_type_has_alg(alg_name, &crypto_skcipher_type, type, mask);
867}
868EXPORT_SYMBOL_GPL(crypto_has_skcipher);
869
870int skcipher_prepare_alg_common(struct skcipher_alg_common *alg)
871{
872 struct crypto_alg *base = &alg->base;
873
874 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
875 alg->statesize > PAGE_SIZE / 2 ||
876 (alg->ivsize + alg->statesize) > PAGE_SIZE / 2)
877 return -EINVAL;
878
879 if (!alg->chunksize)
880 alg->chunksize = base->cra_blocksize;
881
882 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
883
884 return 0;
885}
886
887static int skcipher_prepare_alg(struct skcipher_alg *alg)
888{
889 struct crypto_alg *base = &alg->base;
890 int err;
891
892 err = skcipher_prepare_alg_common(&alg->co);
893 if (err)
894 return err;
895
896 if (alg->walksize > PAGE_SIZE / 8)
897 return -EINVAL;
898
899 if (!alg->walksize)
900 alg->walksize = alg->chunksize;
901
902 if (!alg->statesize) {
903 alg->import = skcipher_noimport;
904 alg->export = skcipher_noexport;
905 } else if (!(alg->import && alg->export))
906 return -EINVAL;
907
908 base->cra_type = &crypto_skcipher_type;
909 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
910
911 return 0;
912}
913
914int 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}
925EXPORT_SYMBOL_GPL(crypto_register_skcipher);
926
927void crypto_unregister_skcipher(struct skcipher_alg *alg)
928{
929 crypto_unregister_alg(&alg->base);
930}
931EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
932
933int 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
945err:
946 for (--i; i >= 0; --i)
947 crypto_unregister_skcipher(&algs[i]);
948
949 return ret;
950}
951EXPORT_SYMBOL_GPL(crypto_register_skciphers);
952
953void 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}
960EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
961
962int skcipher_register_instance(struct crypto_template *tmpl,
963 struct skcipher_instance *inst)
964{
965 int err;
966
967 if (WARN_ON(!inst->free))
968 return -EINVAL;
969
970 err = skcipher_prepare_alg(&inst->alg);
971 if (err)
972 return err;
973
974 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
975}
976EXPORT_SYMBOL_GPL(skcipher_register_instance);
977
978static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
979 unsigned int keylen)
980{
981 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
982
983 crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
984 crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) &
985 CRYPTO_TFM_REQ_MASK);
986 return crypto_cipher_setkey(cipher, key, keylen);
987}
988
989static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
990{
991 struct skcipher_instance *inst = skcipher_alg_instance(tfm);
992 struct crypto_cipher_spawn *spawn = skcipher_instance_ctx(inst);
993 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
994 struct crypto_cipher *cipher;
995
996 cipher = crypto_spawn_cipher(spawn);
997 if (IS_ERR(cipher))
998 return PTR_ERR(cipher);
999
1000 ctx->cipher = cipher;
1001 return 0;
1002}
1003
1004static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
1005{
1006 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1007
1008 crypto_free_cipher(ctx->cipher);
1009}
1010
1011static void skcipher_free_instance_simple(struct skcipher_instance *inst)
1012{
1013 crypto_drop_cipher(skcipher_instance_ctx(inst));
1014 kfree(inst);
1015}
1016
1017/**
1018 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
1019 *
1020 * Allocate an skcipher_instance for a simple block cipher mode of operation,
1021 * e.g. cbc or ecb. The instance context will have just a single crypto_spawn,
1022 * that for the underlying cipher. The {min,max}_keysize, ivsize, blocksize,
1023 * alignmask, and priority are set from the underlying cipher but can be
1024 * overridden if needed. The tfm context defaults to skcipher_ctx_simple, and
1025 * default ->setkey(), ->init(), and ->exit() methods are installed.
1026 *
1027 * @tmpl: the template being instantiated
1028 * @tb: the template parameters
1029 *
1030 * Return: a pointer to the new instance, or an ERR_PTR(). The caller still
1031 * needs to register the instance.
1032 */
1033struct skcipher_instance *skcipher_alloc_instance_simple(
1034 struct crypto_template *tmpl, struct rtattr **tb)
1035{
1036 u32 mask;
1037 struct skcipher_instance *inst;
1038 struct crypto_cipher_spawn *spawn;
1039 struct crypto_alg *cipher_alg;
1040 int err;
1041
1042 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
1043 if (err)
1044 return ERR_PTR(err);
1045
1046 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
1047 if (!inst)
1048 return ERR_PTR(-ENOMEM);
1049 spawn = skcipher_instance_ctx(inst);
1050
1051 err = crypto_grab_cipher(spawn, skcipher_crypto_instance(inst),
1052 crypto_attr_alg_name(tb[1]), 0, mask);
1053 if (err)
1054 goto err_free_inst;
1055 cipher_alg = crypto_spawn_cipher_alg(spawn);
1056
1057 err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name,
1058 cipher_alg);
1059 if (err)
1060 goto err_free_inst;
1061
1062 inst->free = skcipher_free_instance_simple;
1063
1064 /* Default algorithm properties, can be overridden */
1065 inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1066 inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1067 inst->alg.base.cra_priority = cipher_alg->cra_priority;
1068 inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1069 inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1070 inst->alg.ivsize = cipher_alg->cra_blocksize;
1071
1072 /* Use skcipher_ctx_simple by default, can be overridden */
1073 inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1074 inst->alg.setkey = skcipher_setkey_simple;
1075 inst->alg.init = skcipher_init_tfm_simple;
1076 inst->alg.exit = skcipher_exit_tfm_simple;
1077
1078 return inst;
1079
1080err_free_inst:
1081 skcipher_free_instance_simple(inst);
1082 return ERR_PTR(err);
1083}
1084EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1085
1086MODULE_LICENSE("GPL");
1087MODULE_DESCRIPTION("Symmetric key cipher type");
1088MODULE_IMPORT_NS("CRYPTO_INTERNAL");