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: &walk->in);
54}
55
56static inline void skcipher_map_dst(struct skcipher_walk *walk)
57{
58 walk->dst.virt.addr = scatterwalk_map(walk: &walk->out);
59}
60
61static inline void skcipher_unmap_src(struct skcipher_walk *walk)
62{
63 scatterwalk_unmap(vaddr: walk->src.virt.addr);
64}
65
66static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
67{
68 scatterwalk_unmap(vaddr: 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 inline struct crypto_istat_cipher *skcipher_get_stat(
93 struct skcipher_alg *alg)
94{
95 return skcipher_get_stat_common(alg: &alg->co);
96}
97
98static inline int crypto_skcipher_errstat(struct skcipher_alg *alg, int err)
99{
100 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
101
102 if (!IS_ENABLED(CONFIG_CRYPTO_STATS))
103 return err;
104
105 if (err && err != -EINPROGRESS && err != -EBUSY)
106 atomic64_inc(v: &istat->err_cnt);
107
108 return err;
109}
110
111static int skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
112{
113 u8 *addr;
114
115 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
116 addr = skcipher_get_spot(start: addr, len: bsize);
117 scatterwalk_copychunks(buf: addr, walk: &walk->out, nbytes: bsize,
118 out: (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
119 return 0;
120}
121
122int skcipher_walk_done(struct skcipher_walk *walk, int err)
123{
124 unsigned int n = walk->nbytes;
125 unsigned int nbytes = 0;
126
127 if (!n)
128 goto finish;
129
130 if (likely(err >= 0)) {
131 n -= err;
132 nbytes = walk->total - n;
133 }
134
135 if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
136 SKCIPHER_WALK_SLOW |
137 SKCIPHER_WALK_COPY |
138 SKCIPHER_WALK_DIFF)))) {
139unmap_src:
140 skcipher_unmap_src(walk);
141 } else if (walk->flags & SKCIPHER_WALK_DIFF) {
142 skcipher_unmap_dst(walk);
143 goto unmap_src;
144 } else if (walk->flags & SKCIPHER_WALK_COPY) {
145 skcipher_map_dst(walk);
146 memcpy(walk->dst.virt.addr, walk->page, n);
147 skcipher_unmap_dst(walk);
148 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
149 if (err > 0) {
150 /*
151 * Didn't process all bytes. Either the algorithm is
152 * broken, or this was the last step and it turned out
153 * the message wasn't evenly divisible into blocks but
154 * the algorithm requires it.
155 */
156 err = -EINVAL;
157 nbytes = 0;
158 } else
159 n = skcipher_done_slow(walk, bsize: n);
160 }
161
162 if (err > 0)
163 err = 0;
164
165 walk->total = nbytes;
166 walk->nbytes = 0;
167
168 scatterwalk_advance(walk: &walk->in, nbytes: n);
169 scatterwalk_advance(walk: &walk->out, nbytes: n);
170 scatterwalk_done(walk: &walk->in, out: 0, more: nbytes);
171 scatterwalk_done(walk: &walk->out, out: 1, more: nbytes);
172
173 if (nbytes) {
174 crypto_yield(flags: walk->flags & SKCIPHER_WALK_SLEEP ?
175 CRYPTO_TFM_REQ_MAY_SLEEP : 0);
176 return skcipher_walk_next(walk);
177 }
178
179finish:
180 /* Short-circuit for the common/fast path. */
181 if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
182 goto out;
183
184 if (walk->flags & SKCIPHER_WALK_PHYS)
185 goto out;
186
187 if (walk->iv != walk->oiv)
188 memcpy(walk->oiv, walk->iv, walk->ivsize);
189 if (walk->buffer != walk->page)
190 kfree(objp: walk->buffer);
191 if (walk->page)
192 free_page((unsigned long)walk->page);
193
194out:
195 return err;
196}
197EXPORT_SYMBOL_GPL(skcipher_walk_done);
198
199void skcipher_walk_complete(struct skcipher_walk *walk, int err)
200{
201 struct skcipher_walk_buffer *p, *tmp;
202
203 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
204 u8 *data;
205
206 if (err)
207 goto done;
208
209 data = p->data;
210 if (!data) {
211 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
212 data = skcipher_get_spot(start: data, len: walk->stride);
213 }
214
215 scatterwalk_copychunks(buf: data, walk: &p->dst, nbytes: p->len, out: 1);
216
217 if (offset_in_page(p->data) + p->len + walk->stride >
218 PAGE_SIZE)
219 free_page((unsigned long)p->data);
220
221done:
222 list_del(entry: &p->entry);
223 kfree(objp: p);
224 }
225
226 if (!err && walk->iv != walk->oiv)
227 memcpy(walk->oiv, walk->iv, walk->ivsize);
228 if (walk->buffer != walk->page)
229 kfree(objp: walk->buffer);
230 if (walk->page)
231 free_page((unsigned long)walk->page);
232}
233EXPORT_SYMBOL_GPL(skcipher_walk_complete);
234
235static void skcipher_queue_write(struct skcipher_walk *walk,
236 struct skcipher_walk_buffer *p)
237{
238 p->dst = walk->out;
239 list_add_tail(new: &p->entry, head: &walk->buffers);
240}
241
242static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
243{
244 bool phys = walk->flags & SKCIPHER_WALK_PHYS;
245 unsigned alignmask = walk->alignmask;
246 struct skcipher_walk_buffer *p;
247 unsigned a;
248 unsigned n;
249 u8 *buffer;
250 void *v;
251
252 if (!phys) {
253 if (!walk->buffer)
254 walk->buffer = walk->page;
255 buffer = walk->buffer;
256 if (buffer)
257 goto ok;
258 }
259
260 /* Start with the minimum alignment of kmalloc. */
261 a = crypto_tfm_ctx_alignment() - 1;
262 n = bsize;
263
264 if (phys) {
265 /* Calculate the minimum alignment of p->buffer. */
266 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
267 n += sizeof(*p);
268 }
269
270 /* Minimum size to align p->buffer by alignmask. */
271 n += alignmask & ~a;
272
273 /* Minimum size to ensure p->buffer does not straddle a page. */
274 n += (bsize - 1) & ~(alignmask | a);
275
276 v = kzalloc(size: n, flags: skcipher_walk_gfp(walk));
277 if (!v)
278 return skcipher_walk_done(walk, -ENOMEM);
279
280 if (phys) {
281 p = v;
282 p->len = bsize;
283 skcipher_queue_write(walk, p);
284 buffer = p->buffer;
285 } else {
286 walk->buffer = v;
287 buffer = v;
288 }
289
290ok:
291 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
292 walk->dst.virt.addr = skcipher_get_spot(start: walk->dst.virt.addr, len: bsize);
293 walk->src.virt.addr = walk->dst.virt.addr;
294
295 scatterwalk_copychunks(buf: walk->src.virt.addr, walk: &walk->in, nbytes: bsize, out: 0);
296
297 walk->nbytes = bsize;
298 walk->flags |= SKCIPHER_WALK_SLOW;
299
300 return 0;
301}
302
303static int skcipher_next_copy(struct skcipher_walk *walk)
304{
305 struct skcipher_walk_buffer *p;
306 u8 *tmp = walk->page;
307
308 skcipher_map_src(walk);
309 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
310 skcipher_unmap_src(walk);
311
312 walk->src.virt.addr = tmp;
313 walk->dst.virt.addr = tmp;
314
315 if (!(walk->flags & SKCIPHER_WALK_PHYS))
316 return 0;
317
318 p = kmalloc(size: sizeof(*p), flags: skcipher_walk_gfp(walk));
319 if (!p)
320 return -ENOMEM;
321
322 p->data = walk->page;
323 p->len = walk->nbytes;
324 skcipher_queue_write(walk, p);
325
326 if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
327 PAGE_SIZE)
328 walk->page = NULL;
329 else
330 walk->page += walk->nbytes;
331
332 return 0;
333}
334
335static int skcipher_next_fast(struct skcipher_walk *walk)
336{
337 unsigned long diff;
338
339 walk->src.phys.page = scatterwalk_page(walk: &walk->in);
340 walk->src.phys.offset = offset_in_page(walk->in.offset);
341 walk->dst.phys.page = scatterwalk_page(walk: &walk->out);
342 walk->dst.phys.offset = offset_in_page(walk->out.offset);
343
344 if (walk->flags & SKCIPHER_WALK_PHYS)
345 return 0;
346
347 diff = walk->src.phys.offset - walk->dst.phys.offset;
348 diff |= walk->src.virt.page - walk->dst.virt.page;
349
350 skcipher_map_src(walk);
351 walk->dst.virt.addr = walk->src.virt.addr;
352
353 if (diff) {
354 walk->flags |= SKCIPHER_WALK_DIFF;
355 skcipher_map_dst(walk);
356 }
357
358 return 0;
359}
360
361static int skcipher_walk_next(struct skcipher_walk *walk)
362{
363 unsigned int bsize;
364 unsigned int n;
365 int err;
366
367 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
368 SKCIPHER_WALK_DIFF);
369
370 n = walk->total;
371 bsize = min(walk->stride, max(n, walk->blocksize));
372 n = scatterwalk_clamp(walk: &walk->in, nbytes: n);
373 n = scatterwalk_clamp(walk: &walk->out, nbytes: n);
374
375 if (unlikely(n < bsize)) {
376 if (unlikely(walk->total < walk->blocksize))
377 return skcipher_walk_done(walk, -EINVAL);
378
379slow_path:
380 err = skcipher_next_slow(walk, bsize);
381 goto set_phys_lowmem;
382 }
383
384 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
385 if (!walk->page) {
386 gfp_t gfp = skcipher_walk_gfp(walk);
387
388 walk->page = (void *)__get_free_page(gfp);
389 if (!walk->page)
390 goto slow_path;
391 }
392
393 walk->nbytes = min_t(unsigned, n,
394 PAGE_SIZE - offset_in_page(walk->page));
395 walk->flags |= SKCIPHER_WALK_COPY;
396 err = skcipher_next_copy(walk);
397 goto set_phys_lowmem;
398 }
399
400 walk->nbytes = n;
401
402 return skcipher_next_fast(walk);
403
404set_phys_lowmem:
405 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
406 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
407 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
408 walk->src.phys.offset &= PAGE_SIZE - 1;
409 walk->dst.phys.offset &= PAGE_SIZE - 1;
410 }
411 return err;
412}
413
414static int skcipher_copy_iv(struct skcipher_walk *walk)
415{
416 unsigned a = crypto_tfm_ctx_alignment() - 1;
417 unsigned alignmask = walk->alignmask;
418 unsigned ivsize = walk->ivsize;
419 unsigned bs = walk->stride;
420 unsigned aligned_bs;
421 unsigned size;
422 u8 *iv;
423
424 aligned_bs = ALIGN(bs, alignmask + 1);
425
426 /* Minimum size to align buffer by alignmask. */
427 size = alignmask & ~a;
428
429 if (walk->flags & SKCIPHER_WALK_PHYS)
430 size += ivsize;
431 else {
432 size += aligned_bs + ivsize;
433
434 /* Minimum size to ensure buffer does not straddle a page. */
435 size += (bs - 1) & ~(alignmask | a);
436 }
437
438 walk->buffer = kmalloc(size, flags: skcipher_walk_gfp(walk));
439 if (!walk->buffer)
440 return -ENOMEM;
441
442 iv = PTR_ALIGN(walk->buffer, alignmask + 1);
443 iv = skcipher_get_spot(start: iv, len: bs) + aligned_bs;
444
445 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
446 return 0;
447}
448
449static int skcipher_walk_first(struct skcipher_walk *walk)
450{
451 if (WARN_ON_ONCE(in_hardirq()))
452 return -EDEADLK;
453
454 walk->buffer = NULL;
455 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
456 int err = skcipher_copy_iv(walk);
457 if (err)
458 return err;
459 }
460
461 walk->page = NULL;
462
463 return skcipher_walk_next(walk);
464}
465
466static int skcipher_walk_skcipher(struct skcipher_walk *walk,
467 struct skcipher_request *req)
468{
469 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
470 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
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: &walk->in, sg: req->src);
481 scatterwalk_start(walk: &walk->out, sg: 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->ivsize = crypto_skcipher_ivsize(tfm);
489 walk->alignmask = crypto_skcipher_alignmask(tfm);
490
491 if (alg->co.base.cra_type != &crypto_skcipher_type)
492 walk->stride = alg->co.chunksize;
493 else
494 walk->stride = alg->walksize;
495
496 return skcipher_walk_first(walk);
497}
498
499int skcipher_walk_virt(struct skcipher_walk *walk,
500 struct skcipher_request *req, bool atomic)
501{
502 int err;
503
504 might_sleep_if(req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP);
505
506 walk->flags &= ~SKCIPHER_WALK_PHYS;
507
508 err = skcipher_walk_skcipher(walk, req);
509
510 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
511
512 return err;
513}
514EXPORT_SYMBOL_GPL(skcipher_walk_virt);
515
516int skcipher_walk_async(struct skcipher_walk *walk,
517 struct skcipher_request *req)
518{
519 walk->flags |= SKCIPHER_WALK_PHYS;
520
521 INIT_LIST_HEAD(list: &walk->buffers);
522
523 return skcipher_walk_skcipher(walk, req);
524}
525EXPORT_SYMBOL_GPL(skcipher_walk_async);
526
527static int skcipher_walk_aead_common(struct skcipher_walk *walk,
528 struct aead_request *req, bool atomic)
529{
530 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
531 int err;
532
533 walk->nbytes = 0;
534 walk->iv = req->iv;
535 walk->oiv = req->iv;
536
537 if (unlikely(!walk->total))
538 return 0;
539
540 walk->flags &= ~SKCIPHER_WALK_PHYS;
541
542 scatterwalk_start(walk: &walk->in, sg: req->src);
543 scatterwalk_start(walk: &walk->out, sg: req->dst);
544
545 scatterwalk_copychunks(NULL, walk: &walk->in, nbytes: req->assoclen, out: 2);
546 scatterwalk_copychunks(NULL, walk: &walk->out, nbytes: req->assoclen, out: 2);
547
548 scatterwalk_done(walk: &walk->in, out: 0, more: walk->total);
549 scatterwalk_done(walk: &walk->out, out: 0, more: walk->total);
550
551 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
552 walk->flags |= SKCIPHER_WALK_SLEEP;
553 else
554 walk->flags &= ~SKCIPHER_WALK_SLEEP;
555
556 walk->blocksize = crypto_aead_blocksize(tfm);
557 walk->stride = crypto_aead_chunksize(tfm);
558 walk->ivsize = crypto_aead_ivsize(tfm);
559 walk->alignmask = crypto_aead_alignmask(tfm);
560
561 err = skcipher_walk_first(walk);
562
563 if (atomic)
564 walk->flags &= ~SKCIPHER_WALK_SLEEP;
565
566 return err;
567}
568
569int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
570 struct aead_request *req, bool atomic)
571{
572 walk->total = req->cryptlen;
573
574 return skcipher_walk_aead_common(walk, req, atomic);
575}
576EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
577
578int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
579 struct aead_request *req, bool atomic)
580{
581 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
582
583 walk->total = req->cryptlen - crypto_aead_authsize(tfm);
584
585 return skcipher_walk_aead_common(walk, req, atomic);
586}
587EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
588
589static void skcipher_set_needkey(struct crypto_skcipher *tfm)
590{
591 if (crypto_skcipher_max_keysize(tfm) != 0)
592 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
593}
594
595static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
596 const u8 *key, unsigned int keylen)
597{
598 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
599 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
600 u8 *buffer, *alignbuffer;
601 unsigned long absize;
602 int ret;
603
604 absize = keylen + alignmask;
605 buffer = kmalloc(size: absize, GFP_ATOMIC);
606 if (!buffer)
607 return -ENOMEM;
608
609 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
610 memcpy(alignbuffer, key, keylen);
611 ret = cipher->setkey(tfm, alignbuffer, keylen);
612 kfree_sensitive(objp: buffer);
613 return ret;
614}
615
616int crypto_skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
617 unsigned int keylen)
618{
619 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
620 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
621 int err;
622
623 if (cipher->co.base.cra_type != &crypto_skcipher_type) {
624 struct crypto_lskcipher **ctx = crypto_skcipher_ctx(tfm);
625
626 crypto_lskcipher_clear_flags(tfm: *ctx, CRYPTO_TFM_REQ_MASK);
627 crypto_lskcipher_set_flags(tfm: *ctx,
628 flags: crypto_skcipher_get_flags(tfm) &
629 CRYPTO_TFM_REQ_MASK);
630 err = crypto_lskcipher_setkey(tfm: *ctx, key, keylen);
631 goto out;
632 }
633
634 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize)
635 return -EINVAL;
636
637 if ((unsigned long)key & alignmask)
638 err = skcipher_setkey_unaligned(tfm, key, keylen);
639 else
640 err = cipher->setkey(tfm, key, keylen);
641
642out:
643 if (unlikely(err)) {
644 skcipher_set_needkey(tfm);
645 return err;
646 }
647
648 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
649 return 0;
650}
651EXPORT_SYMBOL_GPL(crypto_skcipher_setkey);
652
653int crypto_skcipher_encrypt(struct skcipher_request *req)
654{
655 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
656 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
657 int ret;
658
659 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
660 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
661
662 atomic64_inc(v: &istat->encrypt_cnt);
663 atomic64_add(i: req->cryptlen, v: &istat->encrypt_tlen);
664 }
665
666 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
667 ret = -ENOKEY;
668 else if (alg->co.base.cra_type != &crypto_skcipher_type)
669 ret = crypto_lskcipher_encrypt_sg(req);
670 else
671 ret = alg->encrypt(req);
672
673 return crypto_skcipher_errstat(alg, err: ret);
674}
675EXPORT_SYMBOL_GPL(crypto_skcipher_encrypt);
676
677int crypto_skcipher_decrypt(struct skcipher_request *req)
678{
679 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
680 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
681 int ret;
682
683 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
684 struct crypto_istat_cipher *istat = skcipher_get_stat(alg);
685
686 atomic64_inc(v: &istat->decrypt_cnt);
687 atomic64_add(i: req->cryptlen, v: &istat->decrypt_tlen);
688 }
689
690 if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
691 ret = -ENOKEY;
692 else if (alg->co.base.cra_type != &crypto_skcipher_type)
693 ret = crypto_lskcipher_decrypt_sg(req);
694 else
695 ret = alg->decrypt(req);
696
697 return crypto_skcipher_errstat(alg, err: ret);
698}
699EXPORT_SYMBOL_GPL(crypto_skcipher_decrypt);
700
701static int crypto_lskcipher_export(struct skcipher_request *req, void *out)
702{
703 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
704 u8 *ivs = skcipher_request_ctx(req);
705
706 ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
707
708 memcpy(out, ivs + crypto_skcipher_ivsize(tfm),
709 crypto_skcipher_statesize(tfm));
710
711 return 0;
712}
713
714static int crypto_lskcipher_import(struct skcipher_request *req, const void *in)
715{
716 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
717 u8 *ivs = skcipher_request_ctx(req);
718
719 ivs = PTR_ALIGN(ivs, crypto_skcipher_alignmask(tfm) + 1);
720
721 memcpy(ivs + crypto_skcipher_ivsize(tfm), in,
722 crypto_skcipher_statesize(tfm));
723
724 return 0;
725}
726
727static int skcipher_noexport(struct skcipher_request *req, void *out)
728{
729 return 0;
730}
731
732static int skcipher_noimport(struct skcipher_request *req, const void *in)
733{
734 return 0;
735}
736
737int crypto_skcipher_export(struct skcipher_request *req, void *out)
738{
739 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
740 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
741
742 if (alg->co.base.cra_type != &crypto_skcipher_type)
743 return crypto_lskcipher_export(req, out);
744 return alg->export(req, out);
745}
746EXPORT_SYMBOL_GPL(crypto_skcipher_export);
747
748int crypto_skcipher_import(struct skcipher_request *req, const void *in)
749{
750 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
751 struct skcipher_alg *alg = crypto_skcipher_alg(tfm);
752
753 if (alg->co.base.cra_type != &crypto_skcipher_type)
754 return crypto_lskcipher_import(req, in);
755 return alg->import(req, in);
756}
757EXPORT_SYMBOL_GPL(crypto_skcipher_import);
758
759static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
760{
761 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
762 struct skcipher_alg *alg = crypto_skcipher_alg(tfm: skcipher);
763
764 alg->exit(skcipher);
765}
766
767static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
768{
769 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
770 struct skcipher_alg *alg = crypto_skcipher_alg(tfm: skcipher);
771
772 skcipher_set_needkey(tfm: skcipher);
773
774 if (tfm->__crt_alg->cra_type != &crypto_skcipher_type) {
775 unsigned am = crypto_skcipher_alignmask(tfm: skcipher);
776 unsigned reqsize;
777
778 reqsize = am & ~(crypto_tfm_ctx_alignment() - 1);
779 reqsize += crypto_skcipher_ivsize(tfm: skcipher);
780 reqsize += crypto_skcipher_statesize(tfm: skcipher);
781 crypto_skcipher_set_reqsize(skcipher, reqsize);
782
783 return crypto_init_lskcipher_ops_sg(tfm);
784 }
785
786 if (alg->exit)
787 skcipher->base.exit = crypto_skcipher_exit_tfm;
788
789 if (alg->init)
790 return alg->init(skcipher);
791
792 return 0;
793}
794
795static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
796{
797 if (alg->cra_type != &crypto_skcipher_type)
798 return sizeof(struct crypto_lskcipher *);
799
800 return crypto_alg_extsize(alg);
801}
802
803static void crypto_skcipher_free_instance(struct crypto_instance *inst)
804{
805 struct skcipher_instance *skcipher =
806 container_of(inst, struct skcipher_instance, s.base);
807
808 skcipher->free(skcipher);
809}
810
811static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
812 __maybe_unused;
813static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
814{
815 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
816
817 seq_printf(m, fmt: "type : skcipher\n");
818 seq_printf(m, fmt: "async : %s\n",
819 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
820 seq_printf(m, fmt: "blocksize : %u\n", alg->cra_blocksize);
821 seq_printf(m, fmt: "min keysize : %u\n", skcipher->min_keysize);
822 seq_printf(m, fmt: "max keysize : %u\n", skcipher->max_keysize);
823 seq_printf(m, fmt: "ivsize : %u\n", skcipher->ivsize);
824 seq_printf(m, fmt: "chunksize : %u\n", skcipher->chunksize);
825 seq_printf(m, fmt: "walksize : %u\n", skcipher->walksize);
826 seq_printf(m, fmt: "statesize : %u\n", skcipher->statesize);
827}
828
829static int __maybe_unused crypto_skcipher_report(
830 struct sk_buff *skb, struct crypto_alg *alg)
831{
832 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
833 struct crypto_report_blkcipher rblkcipher;
834
835 memset(&rblkcipher, 0, sizeof(rblkcipher));
836
837 strscpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
838 strscpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
839
840 rblkcipher.blocksize = alg->cra_blocksize;
841 rblkcipher.min_keysize = skcipher->min_keysize;
842 rblkcipher.max_keysize = skcipher->max_keysize;
843 rblkcipher.ivsize = skcipher->ivsize;
844
845 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_BLKCIPHER,
846 attrlen: sizeof(rblkcipher), data: &rblkcipher);
847}
848
849static int __maybe_unused crypto_skcipher_report_stat(
850 struct sk_buff *skb, struct crypto_alg *alg)
851{
852 struct skcipher_alg *skcipher = __crypto_skcipher_alg(alg);
853 struct crypto_istat_cipher *istat;
854 struct crypto_stat_cipher rcipher;
855
856 istat = skcipher_get_stat(alg: skcipher);
857
858 memset(&rcipher, 0, sizeof(rcipher));
859
860 strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
861
862 rcipher.stat_encrypt_cnt = atomic64_read(v: &istat->encrypt_cnt);
863 rcipher.stat_encrypt_tlen = atomic64_read(v: &istat->encrypt_tlen);
864 rcipher.stat_decrypt_cnt = atomic64_read(v: &istat->decrypt_cnt);
865 rcipher.stat_decrypt_tlen = atomic64_read(v: &istat->decrypt_tlen);
866 rcipher.stat_err_cnt = atomic64_read(v: &istat->err_cnt);
867
868 return nla_put(skb, attrtype: CRYPTOCFGA_STAT_CIPHER, attrlen: sizeof(rcipher), data: &rcipher);
869}
870
871static const struct crypto_type crypto_skcipher_type = {
872 .extsize = crypto_skcipher_extsize,
873 .init_tfm = crypto_skcipher_init_tfm,
874 .free = crypto_skcipher_free_instance,
875#ifdef CONFIG_PROC_FS
876 .show = crypto_skcipher_show,
877#endif
878#if IS_ENABLED(CONFIG_CRYPTO_USER)
879 .report = crypto_skcipher_report,
880#endif
881#ifdef CONFIG_CRYPTO_STATS
882 .report_stat = crypto_skcipher_report_stat,
883#endif
884 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
885 .maskset = CRYPTO_ALG_TYPE_SKCIPHER_MASK,
886 .type = CRYPTO_ALG_TYPE_SKCIPHER,
887 .tfmsize = offsetof(struct crypto_skcipher, base),
888};
889
890int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
891 struct crypto_instance *inst,
892 const char *name, u32 type, u32 mask)
893{
894 spawn->base.frontend = &crypto_skcipher_type;
895 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
896}
897EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
898
899struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
900 u32 type, u32 mask)
901{
902 return crypto_alloc_tfm(alg_name, frontend: &crypto_skcipher_type, type, mask);
903}
904EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
905
906struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(
907 const char *alg_name, u32 type, u32 mask)
908{
909 struct crypto_skcipher *tfm;
910
911 /* Only sync algorithms allowed. */
912 mask |= CRYPTO_ALG_ASYNC | CRYPTO_ALG_SKCIPHER_REQSIZE_LARGE;
913
914 tfm = crypto_alloc_tfm(alg_name, frontend: &crypto_skcipher_type, type, mask);
915
916 /*
917 * Make sure we do not allocate something that might get used with
918 * an on-stack request: check the request size.
919 */
920 if (!IS_ERR(ptr: tfm) && WARN_ON(crypto_skcipher_reqsize(tfm) >
921 MAX_SYNC_SKCIPHER_REQSIZE)) {
922 crypto_free_skcipher(tfm);
923 return ERR_PTR(error: -EINVAL);
924 }
925
926 return (struct crypto_sync_skcipher *)tfm;
927}
928EXPORT_SYMBOL_GPL(crypto_alloc_sync_skcipher);
929
930int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask)
931{
932 return crypto_type_has_alg(name: alg_name, frontend: &crypto_skcipher_type, type, mask);
933}
934EXPORT_SYMBOL_GPL(crypto_has_skcipher);
935
936int skcipher_prepare_alg_common(struct skcipher_alg_common *alg)
937{
938 struct crypto_istat_cipher *istat = skcipher_get_stat_common(alg);
939 struct crypto_alg *base = &alg->base;
940
941 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
942 alg->statesize > PAGE_SIZE / 2 ||
943 (alg->ivsize + alg->statesize) > PAGE_SIZE / 2)
944 return -EINVAL;
945
946 if (!alg->chunksize)
947 alg->chunksize = base->cra_blocksize;
948
949 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
950
951 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
952 memset(istat, 0, sizeof(*istat));
953
954 return 0;
955}
956
957static int skcipher_prepare_alg(struct skcipher_alg *alg)
958{
959 struct crypto_alg *base = &alg->base;
960 int err;
961
962 err = skcipher_prepare_alg_common(alg: &alg->co);
963 if (err)
964 return err;
965
966 if (alg->walksize > PAGE_SIZE / 8)
967 return -EINVAL;
968
969 if (!alg->walksize)
970 alg->walksize = alg->chunksize;
971
972 if (!alg->statesize) {
973 alg->import = skcipher_noimport;
974 alg->export = skcipher_noexport;
975 } else if (!(alg->import && alg->export))
976 return -EINVAL;
977
978 base->cra_type = &crypto_skcipher_type;
979 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
980
981 return 0;
982}
983
984int crypto_register_skcipher(struct skcipher_alg *alg)
985{
986 struct crypto_alg *base = &alg->base;
987 int err;
988
989 err = skcipher_prepare_alg(alg);
990 if (err)
991 return err;
992
993 return crypto_register_alg(alg: base);
994}
995EXPORT_SYMBOL_GPL(crypto_register_skcipher);
996
997void crypto_unregister_skcipher(struct skcipher_alg *alg)
998{
999 crypto_unregister_alg(alg: &alg->base);
1000}
1001EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
1002
1003int crypto_register_skciphers(struct skcipher_alg *algs, int count)
1004{
1005 int i, ret;
1006
1007 for (i = 0; i < count; i++) {
1008 ret = crypto_register_skcipher(&algs[i]);
1009 if (ret)
1010 goto err;
1011 }
1012
1013 return 0;
1014
1015err:
1016 for (--i; i >= 0; --i)
1017 crypto_unregister_skcipher(&algs[i]);
1018
1019 return ret;
1020}
1021EXPORT_SYMBOL_GPL(crypto_register_skciphers);
1022
1023void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
1024{
1025 int i;
1026
1027 for (i = count - 1; i >= 0; --i)
1028 crypto_unregister_skcipher(&algs[i]);
1029}
1030EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
1031
1032int skcipher_register_instance(struct crypto_template *tmpl,
1033 struct skcipher_instance *inst)
1034{
1035 int err;
1036
1037 if (WARN_ON(!inst->free))
1038 return -EINVAL;
1039
1040 err = skcipher_prepare_alg(alg: &inst->alg);
1041 if (err)
1042 return err;
1043
1044 return crypto_register_instance(tmpl, inst: skcipher_crypto_instance(inst));
1045}
1046EXPORT_SYMBOL_GPL(skcipher_register_instance);
1047
1048static int skcipher_setkey_simple(struct crypto_skcipher *tfm, const u8 *key,
1049 unsigned int keylen)
1050{
1051 struct crypto_cipher *cipher = skcipher_cipher_simple(tfm);
1052
1053 crypto_cipher_clear_flags(tfm: cipher, CRYPTO_TFM_REQ_MASK);
1054 crypto_cipher_set_flags(tfm: cipher, flags: crypto_skcipher_get_flags(tfm) &
1055 CRYPTO_TFM_REQ_MASK);
1056 return crypto_cipher_setkey(tfm: cipher, key, keylen);
1057}
1058
1059static int skcipher_init_tfm_simple(struct crypto_skcipher *tfm)
1060{
1061 struct skcipher_instance *inst = skcipher_alg_instance(skcipher: tfm);
1062 struct crypto_cipher_spawn *spawn = skcipher_instance_ctx(inst);
1063 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1064 struct crypto_cipher *cipher;
1065
1066 cipher = crypto_spawn_cipher(spawn);
1067 if (IS_ERR(ptr: cipher))
1068 return PTR_ERR(ptr: cipher);
1069
1070 ctx->cipher = cipher;
1071 return 0;
1072}
1073
1074static void skcipher_exit_tfm_simple(struct crypto_skcipher *tfm)
1075{
1076 struct skcipher_ctx_simple *ctx = crypto_skcipher_ctx(tfm);
1077
1078 crypto_free_cipher(tfm: ctx->cipher);
1079}
1080
1081static void skcipher_free_instance_simple(struct skcipher_instance *inst)
1082{
1083 crypto_drop_cipher(spawn: skcipher_instance_ctx(inst));
1084 kfree(objp: inst);
1085}
1086
1087/**
1088 * skcipher_alloc_instance_simple - allocate instance of simple block cipher mode
1089 *
1090 * Allocate an skcipher_instance for a simple block cipher mode of operation,
1091 * e.g. cbc or ecb. The instance context will have just a single crypto_spawn,
1092 * that for the underlying cipher. The {min,max}_keysize, ivsize, blocksize,
1093 * alignmask, and priority are set from the underlying cipher but can be
1094 * overridden if needed. The tfm context defaults to skcipher_ctx_simple, and
1095 * default ->setkey(), ->init(), and ->exit() methods are installed.
1096 *
1097 * @tmpl: the template being instantiated
1098 * @tb: the template parameters
1099 *
1100 * Return: a pointer to the new instance, or an ERR_PTR(). The caller still
1101 * needs to register the instance.
1102 */
1103struct skcipher_instance *skcipher_alloc_instance_simple(
1104 struct crypto_template *tmpl, struct rtattr **tb)
1105{
1106 u32 mask;
1107 struct skcipher_instance *inst;
1108 struct crypto_cipher_spawn *spawn;
1109 struct crypto_alg *cipher_alg;
1110 int err;
1111
1112 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER, mask_ret: &mask);
1113 if (err)
1114 return ERR_PTR(error: err);
1115
1116 inst = kzalloc(size: sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
1117 if (!inst)
1118 return ERR_PTR(error: -ENOMEM);
1119 spawn = skcipher_instance_ctx(inst);
1120
1121 err = crypto_grab_cipher(spawn, inst: skcipher_crypto_instance(inst),
1122 name: crypto_attr_alg_name(rta: tb[1]), type: 0, mask);
1123 if (err)
1124 goto err_free_inst;
1125 cipher_alg = crypto_spawn_cipher_alg(spawn);
1126
1127 err = crypto_inst_setname(inst: skcipher_crypto_instance(inst), name: tmpl->name,
1128 alg: cipher_alg);
1129 if (err)
1130 goto err_free_inst;
1131
1132 inst->free = skcipher_free_instance_simple;
1133
1134 /* Default algorithm properties, can be overridden */
1135 inst->alg.base.cra_blocksize = cipher_alg->cra_blocksize;
1136 inst->alg.base.cra_alignmask = cipher_alg->cra_alignmask;
1137 inst->alg.base.cra_priority = cipher_alg->cra_priority;
1138 inst->alg.min_keysize = cipher_alg->cra_cipher.cia_min_keysize;
1139 inst->alg.max_keysize = cipher_alg->cra_cipher.cia_max_keysize;
1140 inst->alg.ivsize = cipher_alg->cra_blocksize;
1141
1142 /* Use skcipher_ctx_simple by default, can be overridden */
1143 inst->alg.base.cra_ctxsize = sizeof(struct skcipher_ctx_simple);
1144 inst->alg.setkey = skcipher_setkey_simple;
1145 inst->alg.init = skcipher_init_tfm_simple;
1146 inst->alg.exit = skcipher_exit_tfm_simple;
1147
1148 return inst;
1149
1150err_free_inst:
1151 skcipher_free_instance_simple(inst);
1152 return ERR_PTR(error: err);
1153}
1154EXPORT_SYMBOL_GPL(skcipher_alloc_instance_simple);
1155
1156MODULE_LICENSE("GPL");
1157MODULE_DESCRIPTION("Symmetric key cipher type");
1158MODULE_IMPORT_NS(CRYPTO_INTERNAL);
1159

source code of linux/crypto/skcipher.c