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
28 #include "internal.h"
29
30 enum {
31 SKCIPHER_WALK_PHYS = 1 << 0,
32 SKCIPHER_WALK_SLOW = 1 << 1,
33 SKCIPHER_WALK_COPY = 1 << 2,
34 SKCIPHER_WALK_DIFF = 1 << 3,
35 SKCIPHER_WALK_SLEEP = 1 << 4,
36 };
37
38 struct skcipher_walk_buffer {
39 struct list_head entry;
40 struct scatter_walk dst;
41 unsigned int len;
42 u8 *data;
43 u8 buffer[];
44 };
45
46 static int skcipher_walk_next(struct skcipher_walk *walk);
47
skcipher_map_src(struct skcipher_walk * walk)48 static inline void skcipher_map_src(struct skcipher_walk *walk)
49 {
50 walk->src.virt.addr = scatterwalk_map(&walk->in);
51 }
52
skcipher_map_dst(struct skcipher_walk * walk)53 static inline void skcipher_map_dst(struct skcipher_walk *walk)
54 {
55 walk->dst.virt.addr = scatterwalk_map(&walk->out);
56 }
57
skcipher_unmap_src(struct skcipher_walk * walk)58 static inline void skcipher_unmap_src(struct skcipher_walk *walk)
59 {
60 scatterwalk_unmap(walk->src.virt.addr);
61 }
62
skcipher_unmap_dst(struct skcipher_walk * walk)63 static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
64 {
65 scatterwalk_unmap(walk->dst.virt.addr);
66 }
67
skcipher_walk_gfp(struct skcipher_walk * walk)68 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
69 {
70 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
71 }
72
73 /* Get a spot of the specified length that does not straddle a page.
74 * The caller needs to ensure that there is enough space for this operation.
75 */
skcipher_get_spot(u8 * start,unsigned int len)76 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
77 {
78 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
79
80 return max(start, end_page);
81 }
82
__crypto_skcipher_alg(struct crypto_alg * alg)83 static inline struct skcipher_alg *__crypto_skcipher_alg(
84 struct crypto_alg *alg)
85 {
86 return container_of(alg, struct skcipher_alg, base);
87 }
88
skcipher_get_stat(struct skcipher_alg * alg)89 static inline struct crypto_istat_cipher *skcipher_get_stat(
90 struct skcipher_alg *alg)
91 {
92 #ifdef CONFIG_CRYPTO_STATS
93 return &alg->stat;
94 #else
95 return NULL;
96 #endif
97 }
98
crypto_skcipher_errstat(struct skcipher_alg * alg,int err)99 static inline int crypto_skcipher_errstat(struct skcipher_alg *alg, int err)
100 {
101 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
102
103 if (!IS_ENABLED(CONFIG_CRYPTO_STATS))
104 return err;
105
106 if (err && err != -EINPROGRESS && err != -EBUSY)
107 atomic64_inc(&istat->err_cnt);
108
109 return err;
110 }
111
skcipher_done_slow(struct skcipher_walk * walk,unsigned int bsize)112 static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
113 {
114 u8 *addr;
115
116 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
117 addr = skcipher_get_spot(addr, bsize);
118 scatterwalk_copychunks(addr, &walk->out, bsize,
119 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
120 return 0;
121 }
122
skcipher_walk_done(struct skcipher_walk * walk,int err)123 int skcipher_walk_done(struct skcipher_walk *walk, int err)
124 {
125 unsigned int n = walk->nbytes;
126 unsigned int nbytes = 0;
127
128 if (!n)
129 goto finish;
130
131 if (likely(err >= 0)) {
132 n -= err;
133 nbytes = walk->total - n;
134 }
135
136 if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
137 SKCIPHER_WALK_SLOW |
138 SKCIPHER_WALK_COPY |
139 SKCIPHER_WALK_DIFF)))) {
140 unmap_src:
141 skcipher_unmap_src(walk);
142 } else if (walk->flags & SKCIPHER_WALK_DIFF) {
143 skcipher_unmap_dst(walk);
144 goto unmap_src;
145 } else if (walk->flags & SKCIPHER_WALK_COPY) {
146 skcipher_map_dst(walk);
147 memcpy(walk->dst.virt.addr, walk->page, n);
148 skcipher_unmap_dst(walk);
149 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
150 if (err > 0) {
151 /*
152 * Didn't process all bytes. Either the algorithm is
153 * broken, or this was the last step and it turned out
154 * the message wasn't evenly divisible into blocks but
155 * the algorithm requires it.
156 */
157 err = -EINVAL;
158 nbytes = 0;
159 } else
160 n = skcipher_done_slow(walk, n);
161 }
162
163 if (err > 0)
164 err = 0;
165
166 walk->total = nbytes;
167 walk->nbytes = 0;
168
169 scatterwalk_advance(&walk->in, n);
170 scatterwalk_advance(&walk->out, n);
171 scatterwalk_done(&walk->in, 0, nbytes);
172 scatterwalk_done(&walk->out, 1, nbytes);
173
174 if (nbytes) {
175 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
176 CRYPTO_TFM_REQ_MAY_SLEEP : 0);
177 return skcipher_walk_next(walk);
178 }
179
180 finish:
181 /* Short-circuit for the common/fast path. */
182 if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
183 goto out;
184
185 if (walk->flags & SKCIPHER_WALK_PHYS)
186 goto out;
187
188 if (walk->iv != walk->oiv)
189 memcpy(walk->oiv, walk->iv, walk->ivsize);
190 if (walk->buffer != walk->page)
191 kfree(walk->buffer);
192 if (walk->page)
193 free_page((unsigned long)walk->page);
194
195 out:
196 return err;
197 }
198 EXPORT_SYMBOL_GPL(skcipher_walk_done);
199
skcipher_walk_complete(struct skcipher_walk * walk,int err)200 void skcipher_walk_complete(struct skcipher_walk *walk, int err)
201 {
202 struct skcipher_walk_buffer *p, *tmp;
203
204 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
205 u8 *data;
206
207 if (err)
208 goto done;
209
210 data = p->data;
211 if (!data) {
212 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
213 data = skcipher_get_spot(data, walk->stride);
214 }
215
216 scatterwalk_copychunks(data, &p->dst, p->len, 1);
217
218 if (offset_in_page(p->data) + p->len + walk->stride >
219 PAGE_SIZE)
220 free_page((unsigned long)p->data);
221
222 done:
223 list_del(&p->entry);
224 kfree(p);
225 }
226
227 if (!err && walk->iv != walk->oiv)
228 memcpy(walk->oiv, walk->iv, walk->ivsize);
229 if (walk->buffer != walk->page)
230 kfree(walk->buffer);
231 if (walk->page)
232 free_page((unsigned long)walk->page);
233 }
234 EXPORT_SYMBOL_GPL(skcipher_walk_complete);
235
skcipher_queue_write(struct skcipher_walk * walk,struct skcipher_walk_buffer * p)236 static void skcipher_queue_write(struct skcipher_walk *walk,
237 struct skcipher_walk_buffer *p)
238 {
239 p->dst = walk->out;
240 list_add_tail(&p->entry, &walk->buffers);
241 }
242
skcipher_next_slow(struct skcipher_walk * walk,unsigned int bsize)243 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
244 {
245 bool phys = walk->flags & SKCIPHER_WALK_PHYS;
246 unsigned alignmask = walk->alignmask;
247 struct skcipher_walk_buffer *p;
248 unsigned a;
249 unsigned n;
250 u8 *buffer;
251 void *v;
252
253 if (!phys) {
254 if (!walk->buffer)
255 walk->buffer = walk->page;
256 buffer = walk->buffer;
257 if (buffer)
258 goto ok;
259 }
260
261 /* Start with the minimum alignment of kmalloc. */
262 a = crypto_tfm_ctx_alignment() - 1;
263 n = bsize;
264
265 if (phys) {
266 /* Calculate the minimum alignment of p->buffer. */
267 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
268 n += sizeof(*p);
269 }
270
271 /* Minimum size to align p->buffer by alignmask. */
272 n += alignmask & ~a;
273
274 /* Minimum size to ensure p->buffer does not straddle a page. */
275 n += (bsize - 1) & ~(alignmask | a);
276
277 v = kzalloc(n, skcipher_walk_gfp(walk));
278 if (!v)
279 return skcipher_walk_done(walk, -ENOMEM);
280
281 if (phys) {
282 p = v;
283 p->len = bsize;
284 skcipher_queue_write(walk, p);
285 buffer = p->buffer;
286 } else {
287 walk->buffer = v;
288 buffer = v;
289 }
290
291 ok:
292 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
293 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
294 walk->src.virt.addr = walk->dst.virt.addr;
295
296 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
297
298 walk->nbytes = bsize;
299 walk->flags |= SKCIPHER_WALK_SLOW;
300
301 return 0;
302 }
303
skcipher_next_copy(struct skcipher_walk * walk)304 static int skcipher_next_copy(struct skcipher_walk *walk)
305 {
306 struct skcipher_walk_buffer *p;
307 u8 *tmp = walk->page;
308
309 skcipher_map_src(walk);
310 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
311 skcipher_unmap_src(walk);
312
313 walk->src.virt.addr = tmp;
314 walk->dst.virt.addr = tmp;
315
316 if (!(walk->flags & SKCIPHER_WALK_PHYS))
317 return 0;
318
319 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
320 if (!p)
321 return -ENOMEM;
322
323 p->data = walk->page;
324 p->len = walk->nbytes;
325 skcipher_queue_write(walk, p);
326
327 if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
328 PAGE_SIZE)
329 walk->page = NULL;
330 else
331 walk->page += walk->nbytes;
332
333 return 0;
334 }
335
skcipher_next_fast(struct skcipher_walk * walk)336 static int skcipher_next_fast(struct skcipher_walk *walk)
337 {
338 unsigned long diff;
339
340 walk->src.phys.page = scatterwalk_page(&walk->in);
341 walk->src.phys.offset = offset_in_page(walk->in.offset);
342 walk->dst.phys.page = scatterwalk_page(&walk->out);
343 walk->dst.phys.offset = offset_in_page(walk->out.offset);
344
345 if (walk->flags & SKCIPHER_WALK_PHYS)
346 return 0;
347
348 diff = walk->src.phys.offset - walk->dst.phys.offset;
349 diff |= walk->src.virt.page - walk->dst.virt.page;
350
351 skcipher_map_src(walk);
352 walk->dst.virt.addr = walk->src.virt.addr;
353
354 if (diff) {
355 walk->flags |= SKCIPHER_WALK_DIFF;
356 skcipher_map_dst(walk);
357 }
358
359 return 0;
360 }
361
skcipher_walk_next(struct skcipher_walk * walk)362 static int skcipher_walk_next(struct skcipher_walk *walk)
363 {
364 unsigned int bsize;
365 unsigned int n;
366 int err;
367
368 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
369 SKCIPHER_WALK_DIFF);
370
371 n = walk->total;
372 bsize = min(walk->stride, max(n, walk->blocksize));
373 n = scatterwalk_clamp(&walk->in, n);
374 n = scatterwalk_clamp(&walk->out, n);
375
376 if (unlikely(n < bsize)) {
377 if (unlikely(walk->total < walk->blocksize))
378 return skcipher_walk_done(walk, -EINVAL);
379
380 slow_path:
381 err = skcipher_next_slow(walk, bsize);
382 goto set_phys_lowmem;
383 }
384
385 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
386 if (!walk->page) {
387 gfp_t gfp = skcipher_walk_gfp(walk);
388
389 walk->page = (void *)__get_free_page(gfp);
390 if (!walk->page)
391 goto slow_path;
392 }
393
394 walk->nbytes = min_t(unsigned, n,
395 PAGE_SIZE - offset_in_page(walk->page));
396 walk->flags |= SKCIPHER_WALK_COPY;
397 err = skcipher_next_copy(walk);
398 goto set_phys_lowmem;
399 }
400
401 walk->nbytes = n;
402
403 return skcipher_next_fast(walk);
404
405 set_phys_lowmem:
406 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
407 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
408 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
409 walk->src.phys.offset &= PAGE_SIZE - 1;
410 walk->dst.phys.offset &= PAGE_SIZE - 1;
411 }
412 return err;
413 }
414
skcipher_copy_iv(struct skcipher_walk * walk)415 static int skcipher_copy_iv(struct skcipher_walk *walk)
416 {
417 unsigned a = crypto_tfm_ctx_alignment() - 1;
418 unsigned alignmask = walk->alignmask;
419 unsigned ivsize = walk->ivsize;
420 unsigned bs = walk->stride;
421 unsigned aligned_bs;
422 unsigned size;
423 u8 *iv;
424
425 aligned_bs = ALIGN(bs, alignmask + 1);
426
427 /* Minimum size to align buffer by alignmask. */
428 size = alignmask & ~a;
429
430 if (walk->flags & SKCIPHER_WALK_PHYS)
431 size += ivsize;
432 else {
433 size += aligned_bs + ivsize;
434
435 /* Minimum size to ensure buffer does not straddle a page. */
436 size += (bs - 1) & ~(alignmask | a);
437 }
438
439 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
440 if (!walk->buffer)
441 return -ENOMEM;
442
443 iv = PTR_ALIGN(walk->buffer, alignmask + 1);
444 iv = skcipher_get_spot(iv, bs) + aligned_bs;
445
446 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
447 return 0;
448 }
449
skcipher_walk_first(struct skcipher_walk * walk)450 static int skcipher_walk_first(struct skcipher_walk *walk)
451 {
452 if (WARN_ON_ONCE(in_hardirq()))
453 return -EDEADLK;
454
455 walk->buffer = NULL;
456 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
457 int err = skcipher_copy_iv(walk);
458 if (err)
459 return err;
460 }
461
462 walk->page = NULL;
463
464 return skcipher_walk_next(walk);
465 }
466
skcipher_walk_skcipher(struct skcipher_walk * walk,struct skcipher_request * req)467 static int skcipher_walk_skcipher(struct skcipher_walk *walk,
468 struct skcipher_request *req)
469 {
470 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
471
472 walk->total = req->cryptlen;
473 walk->nbytes = 0;
474 walk->iv = req->iv;
475 walk->oiv = req->iv;
476
477 if (unlikely(!walk->total))
478 return 0;
479
480 scatterwalk_start(&walk->in, req->src);
481 scatterwalk_start(&walk->out, req->dst);
482
483 walk->flags &= ~SKCIPHER_WALK_SLEEP;
484 walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
485 SKCIPHER_WALK_SLEEP : 0;
486
487 walk->blocksize = crypto_skcipher_blocksize(tfm);
488 walk->stride = crypto_skcipher_walksize(tfm);
489 walk->ivsize = crypto_skcipher_ivsize(tfm);
490 walk->alignmask = crypto_skcipher_alignmask(tfm);
491
492 return skcipher_walk_first(walk);
493 }
494
skcipher_walk_virt(struct skcipher_walk * walk,struct skcipher_request * req,bool atomic)495 int skcipher_walk_virt(struct skcipher_walk *walk,
496 struct skcipher_request *req, bool atomic)
497 {
498 int err;
499
500 might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
501
502 walk->flags &= ~SKCIPHER_WALK_PHYS;
503
504 err = skcipher_walk_skcipher(walk, req);
505
506 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
507
508 return err;
509 }
510 EXPORT_SYMBOL_GPL(skcipher_walk_virt);
511
skcipher_walk_async(struct skcipher_walk * walk,struct skcipher_request * req)512 int skcipher_walk_async(struct skcipher_walk *walk,
513 struct skcipher_request *req)
514 {
515 walk->flags |= SKCIPHER_WALK_PHYS;
516
517 INIT_LIST_HEAD(&walk->buffers);
518
519 return skcipher_walk_skcipher(walk, req);
520 }
521 EXPORT_SYMBOL_GPL(skcipher_walk_async);
522
skcipher_walk_aead_common(struct skcipher_walk * walk,struct aead_request * req,bool atomic)523 static int skcipher_walk_aead_common(struct skcipher_walk *walk,
524 struct aead_request *req, bool atomic)
525 {
526 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
527 int err;
528
529 walk->nbytes = 0;
530 walk->iv = req->iv;
531 walk->oiv = req->iv;
532
533 if (unlikely(!walk->total))
534 return 0;
535
536 walk->flags &= ~SKCIPHER_WALK_PHYS;
537
538 scatterwalk_start(&walk->in, req->src);
539 scatterwalk_start(&walk->out, req->dst);
540
541 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
542 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
543
544 scatterwalk_done(&walk->in, 0, walk->total);
545 scatterwalk_done(&walk->out, 0, walk->total);
546
547 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
548 walk->flags |= SKCIPHER_WALK_SLEEP;
549 else
550 walk->flags &= ~SKCIPHER_WALK_SLEEP;
551
552 walk->blocksize = crypto_aead_blocksize(tfm);
553 walk->stride = crypto_aead_chunksize(tfm);
554 walk->ivsize = crypto_aead_ivsize(tfm);
555 walk->alignmask = crypto_aead_alignmask(tfm);
556
557 err = skcipher_walk_first(walk);
558
559 if (atomic)
560 walk->flags &= ~SKCIPHER_WALK_SLEEP;
561
562 return err;
563 }
564
skcipher_walk_aead_encrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)565 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
566 struct aead_request *req, bool atomic)
567 {
568 walk->total = req->cryptlen;
569
570 return skcipher_walk_aead_common(walk, req, atomic);
571 }
572 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
573
skcipher_walk_aead_decrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)574 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
575 struct aead_request *req, bool atomic)
576 {
577 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
578
579 walk->total = req->cryptlen - crypto_aead_authsize(tfm);
580
581 return skcipher_walk_aead_common(walk, req, atomic);
582 }
583 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
584
skcipher_set_needkey(struct crypto_skcipher * tfm)585 static void skcipher_set_needkey(struct crypto_skcipher *tfm)
586 {
587 if (crypto_skcipher_max_keysize(tfm) != 0)
588 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
589 }
590
skcipher_setkey_unaligned(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)591 static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
592 const u8 *key, unsigned int keylen)
593 {
594 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
595 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
596 u8 *buffer, *alignbuffer;
597 unsigned long absize;
598 int ret;
599
600 absize = keylen + alignmask;
601 buffer = kmalloc(absize, GFP_ATOMIC);
602 if (!buffer)
603 return -ENOMEM;
604
605 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
606 memcpy(alignbuffer, key, keylen);
607 ret = cipher->setkey(tfm, alignbuffer, keylen);
608 kfree_sensitive(buffer);
609 return ret;
610 }
611
crypto_skcipher_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)612 int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
613 unsigned int keylen)
614 {
615 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
616 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
617 int err;
618
619 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize)
620 return -EINVAL;
621
622 if ((unsigned long)key & alignmask)
623 err = skcipher_setkey_unaligned(tfm, key, keylen);
624 else
625 err = cipher->setkey(tfm, key, keylen);
626
627 if (unlikely(err)) {
628 skcipher_set_needkey(tfm);
629 return err;
630 }
631
632 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
633 return 0;
634 }
635 EXPORT_SYMBOL_GPL(crypto_skcipher_setkey);
636
crypto_skcipher_encrypt(struct skcipher_request * req)637 int crypto_skcipher_encrypt(struct skcipher_request *req)
638 {
639 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
640 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
641 int ret;
642
643 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
644 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
645
646 atomic64_inc(&istat->encrypt_cnt);
647 atomic64_add(req->cryptlen, &istat->encrypt_tlen);
648 }
649
650 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
651 ret = -ENOKEY;
652 else
653 ret = alg->encrypt(req);
654
655 return crypto_skcipher_errstat(alg, ret);
656 }
657 EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
658
crypto_skcipher_decrypt(struct skcipher_request * req)659 int crypto_skcipher_decrypt(struct skcipher_request *req)
660 {
661 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
662 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
663 int ret;
664
665 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
666 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
667
668 atomic64_inc(&istat->decrypt_cnt);
669 atomic64_add(req->cryptlen, &istat->decrypt_tlen);
670 }
671
672 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
673 ret = -ENOKEY;
674 else
675 ret = alg->decrypt(req);
676
677 return crypto_skcipher_errstat(alg, ret);
678 }
679 EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
680
crypto_skcipher_exit_tfm(struct crypto_tfm * tfm)681 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
682 {
683 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
684 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
685
686 alg->exit(skcipher);
687 }
688
crypto_skcipher_init_tfm(struct crypto_tfm * tfm)689 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
690 {
691 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
692 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
693
694 skcipher_set_needkey(skcipher);
695
696 if (alg->exit)
697 skcipher->base.exit = crypto_skcipher_exit_tfm;
698
699 if (alg->init)
700 return alg->init(skcipher);
701
702 return 0;
703 }
704
crypto_skcipher_free_instance(struct crypto_instance * inst)705 static void crypto_skcipher_free_instance(struct crypto_instance *inst)
706 {
707 struct skcipher_instance *skcipher =
708 container_of(inst, struct skcipher_instance, s.base);
709
710 skcipher->free(skcipher);
711 }
712
713 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
714 __maybe_unused;
crypto_skcipher_show(struct seq_file * m,struct crypto_alg * alg)715 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
716 {
717 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
718
719 seq_printf(m, "type : skcipher\n");
720 seq_printf(m, "async : %s\n",
721 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
722 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
723 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
724 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
725 seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
726 seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
727 seq_printf(m, "walksize : %u\n", skcipher->walksize);
728 }
729
crypto_skcipher_report(struct sk_buff * skb,struct crypto_alg * alg)730 static int __maybe_unused crypto_skcipher_report(
731 struct sk_buff *skb, struct crypto_alg *alg)
732 {
733 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
734 struct crypto_report_blkcipher rblkcipher;
735
736 memset(&rblkcipher, 0, sizeof(rblkcipher));
737
738 strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
739 strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
740
741 rblkcipher.blocksize = alg->cra_blocksize;
742 rblkcipher.min_keysize = skcipher->min_keysize;
743 rblkcipher.max_keysize = skcipher->max_keysize;
744 rblkcipher.ivsize = skcipher->ivsize;
745
746 return nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
747 sizeof(rblkcipher), &rblkcipher);
748 }
749
crypto_skcipher_report_stat(struct sk_buff * skb,struct crypto_alg * alg)750 static int __maybe_unused crypto_skcipher_report_stat(
751 struct sk_buff *skb, struct crypto_alg *alg)
752 {
753 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
754 struct crypto_istat_cipher *istat;
755 struct crypto_stat_cipher rcipher;
756
757 istat = skcipher_get_stat(skcipher);
758
759 memset(&rcipher, 0, sizeof(rcipher));
760
761 strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
762
763 rcipher.stat_encrypt_cnt = atomic64_read(&istat->encrypt_cnt);
764 rcipher.stat_encrypt_tlen = atomic64_read(&istat->encrypt_tlen);
765 rcipher.stat_decrypt_cnt = atomic64_read(&istat->decrypt_cnt);
766 rcipher.stat_decrypt_tlen = atomic64_read(&istat->decrypt_tlen);
767 rcipher.stat_err_cnt = atomic64_read(&istat->err_cnt);
768
769 return nla_put(skb, CRYPTOCFGA_STAT_CIPHER, sizeof(rcipher), &rcipher);
770 }
771
772 static const struct crypto_type crypto_skcipher_type = {
773 .extsize = crypto_alg_extsize,
774 .init_tfm = crypto_skcipher_init_tfm,
775 .free = crypto_skcipher_free_instance,
776 #ifdef CONFIG_PROC_FS
777 .show = crypto_skcipher_show,
778 #endif
779 #if IS_ENABLED(CONFIG_CRYPTO_USER)
780 .report = crypto_skcipher_report,
781 #endif
782 #ifdef CONFIG_CRYPTO_STATS
783 .report_stat = crypto_skcipher_report_stat,
784 #endif
785 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
786 .maskset = CRYPTO_ALG_TYPE_MASK,
787 .type = CRYPTO_ALG_TYPE_SKCIPHER,
788 .tfmsize = offsetof(struct crypto_skcipher, base),
789 };
790
crypto_grab_skcipher(struct crypto_skcipher_spawn * spawn,struct crypto_instance * inst,const char * name,u32 type,u32 mask)791 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
792 struct crypto_instance *inst,
793 const char *name, u32 type, u32 mask)
794 {
795 spawn->base.frontend = &crypto_skcipher_type;
796 return crypto_grab_spawn(&spawn->base, inst, name, type, mask);
797 }
798 EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
799
crypto_alloc_skcipher(const char * alg_name,u32 type,u32 mask)800 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
801 u32 type, u32 mask)
802 {
803 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
804 }
805 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
806
crypto_alloc_sync_skcipher(const char * alg_name,u32 type,u32 mask)807 struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
808 const char *alg_name, u32 type, u32 mask)
809 {
810 struct crypto_skcipher *tfm;
811
812 /* Only sync algorithms allowed. */
813 mask |= CRYPTO_ALG_ASYNC | CRYPTO_ALG_SKCIPHER_REQSIZE_LARGE;
814
815 tfm = crypto_alloc_tfm(alg_name, &crypto_skcipher_type, type, mask);
816
817 /*
818 * Make sure we do not allocate something that might get used with
819 * an on-stack request: check the request size.
820 */
821 if (!IS_ERR(tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
822 MAX_SYNC_SKCIPHER_REQSIZE)) {
823 crypto_free_skcipher(tfm);
824 return ERR_PTR(-EINVAL);
825 }
826
827 return (struct crypto_sync_skcipher *)tfm;
828 }
829 EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
830
crypto_has_skcipher(const char * alg_name,u32 type,u32 mask)831 int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask)
832 {
833 return crypto_type_has_alg(alg_name, &crypto_skcipher_type, type, mask);
834 }
835 EXPORT_SYMBOL_GPL(crypto_has_skcipher);
836
skcipher_prepare_alg(struct skcipher_alg * alg)837 static int skcipher_prepare_alg(struct skcipher_alg *alg)
838 {
839 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
840 struct crypto_alg *base = &alg->base;
841
842 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
843 alg->walksize > PAGE_SIZE / 8)
844 return -EINVAL;
845
846 if (!alg->chunksize)
847 alg->chunksize = base->cra_blocksize;
848 if (!alg->walksize)
849 alg->walksize = alg->chunksize;
850
851 base->cra_type = &crypto_skcipher_type;
852 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
853 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
854
855 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
856 memset(istat, 0, sizeof(*istat));
857
858 return 0;
859 }
860
crypto_register_skcipher(struct skcipher_alg * alg)861 int crypto_register_skcipher(struct skcipher_alg *alg)
862 {
863 struct crypto_alg *base = &alg->base;
864 int err;
865
866 err = skcipher_prepare_alg(alg);
867 if (err)
868 return err;
869
870 return crypto_register_alg(base);
871 }
872 EXPORT_SYMBOL_GPL(crypto_register_skcipher);
873
crypto_unregister_skcipher(struct skcipher_alg * alg)874 void crypto_unregister_skcipher(struct skcipher_alg *alg)
875 {
876 crypto_unregister_alg(&alg->base);
877 }
878 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
879
crypto_register_skciphers(struct skcipher_alg * algs,int count)880 int crypto_register_skciphers(struct skcipher_alg *algs, int count)
881 {
882 int i, ret;
883
884 for (i = 0; i < count; i++) {
885 ret = crypto_register_skcipher(&algs[i]);
886 if (ret)
887 goto err;
888 }
889
890 return 0;
891
892 err:
893 for (--i; i >= 0; --i)
894 crypto_unregister_skcipher(&algs[i]);
895
896 return ret;
897 }
898 EXPORT_SYMBOL_GPL(crypto_register_skciphers);
899
crypto_unregister_skciphers(struct skcipher_alg * algs,int count)900 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
901 {
902 int i;
903
904 for (i = count - 1; i >= 0; --i)
905 crypto_unregister_skcipher(&algs[i]);
906 }
907 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
908
skcipher_register_instance(struct crypto_template * tmpl,struct skcipher_instance * inst)909 int skcipher_register_instance(struct crypto_template *tmpl,
910 struct skcipher_instance *inst)
911 {
912 int err;
913
914 if (WARN_ON(!inst->free))
915 return -EINVAL;
916
917 err = skcipher_prepare_alg(&inst->alg);
918 if (err)
919 return err;
920
921 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
922 }
923 EXPORT_SYMBOL_GPL(skcipher_register_instance);
924
skcipher_setkey_simple(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)925 static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
926 unsigned int keylen)
927 {
928 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
929
930 crypto_cipher_clear_flags(cipher, CRYPTO_TFM_REQ_MASK);
931 crypto_cipher_set_flags(cipher, crypto_skcipher_get_flags(tfm) &
932 CRYPTO_TFM_REQ_MASK);
933 return crypto_cipher_setkey(cipher, key, keylen);
934 }
935
skcipher_init_tfm_simple(struct crypto_skcipher * tfm)936 static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
937 {
938 struct skcipher_instance *inst = skcipher_alg_instance(tfm);
939 struct crypto_cipher_spawn *spawn = skcipher_instance_ctx(inst);
940 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
941 struct crypto_cipher *cipher;
942
943 cipher = crypto_spawn_cipher(spawn);
944 if (IS_ERR(cipher))
945 return PTR_ERR(cipher);
946
947 ctx->cipher = cipher;
948 return 0;
949 }
950
skcipher_exit_tfm_simple(struct crypto_skcipher * tfm)951 static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
952 {
953 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
954
955 crypto_free_cipher(ctx->cipher);
956 }
957
skcipher_free_instance_simple(struct skcipher_instance * inst)958 static void skcipher_free_instance_simple(struct skcipher_instance *inst)
959 {
960 crypto_drop_cipher(skcipher_instance_ctx(inst));
961 kfree(inst);
962 }
963
964 /**
965 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
966 *
967 * Allocate an skcipher_instance for a simple block cipher mode of operation,
968 * e.g. cbc or ecb. The instance context will have just a single crypto_spawn,
969 * that for the underlying cipher. The {min,max}_keysize, ivsize, blocksize,
970 * alignmask, and priority are set from the underlying cipher but can be
971 * overridden if needed. The tfm context defaults to skcipher_ctx_simple, and
972 * default ->setkey(), ->init(), and ->exit() methods are installed.
973 *
974 * @tmpl: the template being instantiated
975 * @tb: the template parameters
976 *
977 * Return: a pointer to the new instance, or an ERR_PTR(). The caller still
978 * needs to register the instance.
979 */
skcipher_alloc_instance_simple(struct crypto_template * tmpl,struct rtattr ** tb)980 struct skcipher_instance *skcipher_alloc_instance_simple(
981 struct crypto_template *tmpl, struct rtattr **tb)
982 {
983 u32 mask;
984 struct skcipher_instance *inst;
985 struct crypto_cipher_spawn *spawn;
986 struct crypto_alg *cipher_alg;
987 int err;
988
989 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, &mask);
990 if (err)
991 return ERR_PTR(err);
992
993 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
994 if (!inst)
995 return ERR_PTR(-ENOMEM);
996 spawn = skcipher_instance_ctx(inst);
997
998 err = crypto_grab_cipher(spawn, skcipher_crypto_instance(inst),
999 crypto_attr_alg_name(tb[1]), 0, mask);
1000 if (err)
1001 goto err_free_inst;
1002 cipher_alg = crypto_spawn_cipher_alg(spawn);
1003
1004 err = crypto_inst_setname(skcipher_crypto_instance(inst), tmpl->name,
1005 cipher_alg);
1006 if (err)
1007 goto err_free_inst;
1008
1009 inst->free = skcipher_free_instance_simple;
1010
1011 /* Default algorithm properties, can be overridden */
1012 inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1013 inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1014 inst->alg.base.cra_priority = cipher_alg->cra_priority;
1015 inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1016 inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1017 inst->alg.ivsize = cipher_alg->cra_blocksize;
1018
1019 /* Use skcipher_ctx_simple by default, can be overridden */
1020 inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1021 inst->alg.setkey = skcipher_setkey_simple;
1022 inst->alg.init = skcipher_init_tfm_simple;
1023 inst->alg.exit = skcipher_exit_tfm_simple;
1024
1025 return inst;
1026
1027 err_free_inst:
1028 skcipher_free_instance_simple(inst);
1029 return ERR_PTR(err);
1030 }
1031 EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1032
1033 MODULE_LICENSE("GPL");
1034 MODULE_DESCRIPTION("Symmetric key cipher type");
1035 MODULE_IMPORT_NS(CRYPTO_INTERNAL);
1036