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
skcipher_unmap(struct scatter_walk * walk,void * vaddr)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
skcipher_map(struct scatter_walk * walk)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
skcipher_map_src(struct skcipher_walk * walk)58 static inline void skcipher_map_src(struct skcipher_walk *walk)
59 {
60 walk->src.virt.addr = skcipher_map(&walk->in);
61 }
62
skcipher_map_dst(struct skcipher_walk * walk)63 static inline void skcipher_map_dst(struct skcipher_walk *walk)
64 {
65 walk->dst.virt.addr = skcipher_map(&walk->out);
66 }
67
skcipher_unmap_src(struct skcipher_walk * walk)68 static inline void skcipher_unmap_src(struct skcipher_walk *walk)
69 {
70 skcipher_unmap(&walk->in, walk->src.virt.addr);
71 }
72
skcipher_unmap_dst(struct skcipher_walk * walk)73 static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
74 {
75 skcipher_unmap(&walk->out, walk->dst.virt.addr);
76 }
77
skcipher_walk_gfp(struct skcipher_walk * walk)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 */
skcipher_get_spot(u8 * start,unsigned int len)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
skcipher_done_slow(struct skcipher_walk * walk,unsigned int bsize)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
skcipher_walk_done(struct skcipher_walk * walk,int err)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
skcipher_walk_complete(struct skcipher_walk * walk,int err)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
skcipher_queue_write(struct skcipher_walk * walk,struct skcipher_walk_buffer * p)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
skcipher_next_slow(struct skcipher_walk * walk,unsigned int bsize)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
skcipher_next_copy(struct skcipher_walk * walk)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
skcipher_next_fast(struct skcipher_walk * walk)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
skcipher_walk_next(struct skcipher_walk * walk)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
skcipher_copy_iv(struct skcipher_walk * walk)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
skcipher_walk_first(struct skcipher_walk * walk)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
skcipher_walk_skcipher(struct skcipher_walk * walk,struct skcipher_request * req)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
skcipher_walk_virt(struct skcipher_walk * walk,struct skcipher_request * req,bool atomic)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
skcipher_walk_atomise(struct skcipher_walk * walk)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
skcipher_walk_async(struct skcipher_walk * walk,struct skcipher_request * req)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
skcipher_walk_aead_common(struct skcipher_walk * walk,struct aead_request * req,bool atomic)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
skcipher_walk_aead(struct skcipher_walk * walk,struct aead_request * req,bool atomic)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
skcipher_walk_aead_encrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)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
skcipher_walk_aead_decrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)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
crypto_skcipher_extsize(struct crypto_alg * alg)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
skcipher_set_needkey(struct crypto_skcipher * tfm)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
skcipher_setkey_blkcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)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
skcipher_crypt_blkcipher(struct skcipher_request * req,int (* crypt)(struct blkcipher_desc *,struct scatterlist *,struct scatterlist *,unsigned int))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
skcipher_encrypt_blkcipher(struct skcipher_request * req)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
skcipher_decrypt_blkcipher(struct skcipher_request * req)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
crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm * tfm)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
crypto_init_skcipher_ops_blkcipher(struct crypto_tfm * tfm)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
skcipher_setkey_ablkcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)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
skcipher_crypt_ablkcipher(struct skcipher_request * req,int (* crypt)(struct ablkcipher_request *))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
skcipher_encrypt_ablkcipher(struct skcipher_request * req)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
skcipher_decrypt_ablkcipher(struct skcipher_request * req)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
crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm * tfm)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
crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm * tfm)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
skcipher_setkey_unaligned(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)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
skcipher_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)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
crypto_skcipher_encrypt(struct skcipher_request * req)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
crypto_skcipher_decrypt(struct skcipher_request * req)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
crypto_skcipher_exit_tfm(struct crypto_tfm * tfm)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
crypto_skcipher_init_tfm(struct crypto_tfm * tfm)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
crypto_skcipher_free_instance(struct crypto_instance * inst)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;
crypto_skcipher_show(struct seq_file * m,struct crypto_alg * alg)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
crypto_skcipher_report(struct sk_buff * skb,struct crypto_alg * alg)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
crypto_skcipher_report(struct sk_buff * skb,struct crypto_alg * alg)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
crypto_grab_skcipher(struct crypto_skcipher_spawn * spawn,const char * name,u32 type,u32 mask)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
crypto_alloc_skcipher(const char * alg_name,u32 type,u32 mask)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
crypto_alloc_sync_skcipher(const char * alg_name,u32 type,u32 mask)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
crypto_has_skcipher2(const char * alg_name,u32 type,u32 mask)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
skcipher_prepare_alg(struct skcipher_alg * alg)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
crypto_register_skcipher(struct skcipher_alg * alg)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
crypto_unregister_skcipher(struct skcipher_alg * alg)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
crypto_register_skciphers(struct skcipher_alg * algs,int count)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
crypto_unregister_skciphers(struct skcipher_alg * algs,int count)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
skcipher_register_instance(struct crypto_template * tmpl,struct skcipher_instance * inst)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
skcipher_setkey_simple(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)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
skcipher_init_tfm_simple(struct crypto_skcipher * tfm)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
skcipher_exit_tfm_simple(struct crypto_skcipher * tfm)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
skcipher_free_instance_simple(struct skcipher_instance * inst)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 *
skcipher_alloc_instance_simple(struct crypto_template * tmpl,struct rtattr ** tb,struct crypto_alg ** cipher_alg_ret)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");
1241
