1 /*
2 * Symmetric key cipher operations.
3 *
4 * Generic encrypt/decrypt wrapper for ciphers, handles operations across
5 * multiple page boundaries by using temporary blocks. In user context,
6 * the kernel is given a chance to schedule us once per page.
7 *
8 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the Free
12 * Software Foundation; either version 2 of the License, or (at your option)
13 * any later version.
14 *
15 */
16
17 #include <crypto/internal/aead.h>
18 #include <crypto/internal/skcipher.h>
19 #include <crypto/scatterwalk.h>
20 #include <linux/bug.h>
21 #include <linux/cryptouser.h>
22 #include <linux/compiler.h>
23 #include <linux/list.h>
24 #include <linux/module.h>
25 #include <linux/rtnetlink.h>
26 #include <linux/seq_file.h>
27 #include <net/netlink.h>
28
29 #include "internal.h"
30
31 enum {
32 SKCIPHER_WALK_PHYS = 1 << 0,
33 SKCIPHER_WALK_SLOW = 1 << 1,
34 SKCIPHER_WALK_COPY = 1 << 2,
35 SKCIPHER_WALK_DIFF = 1 << 3,
36 SKCIPHER_WALK_SLEEP = 1 << 4,
37 };
38
39 struct skcipher_walk_buffer {
40 struct list_head entry;
41 struct scatter_walk dst;
42 unsigned int len;
43 u8 *data;
44 u8 buffer[];
45 };
46
47 static int skcipher_walk_next(struct skcipher_walk *walk);
48
skcipher_unmap(struct scatter_walk * walk,void * vaddr)49 static inline void skcipher_unmap(struct scatter_walk *walk, void *vaddr)
50 {
51 if (PageHighMem(scatterwalk_page(walk)))
52 kunmap_atomic(vaddr);
53 }
54
skcipher_map(struct scatter_walk * walk)55 static inline void *skcipher_map(struct scatter_walk *walk)
56 {
57 struct page *page = scatterwalk_page(walk);
58
59 return (PageHighMem(page) ? kmap_atomic(page) : page_address(page)) +
60 offset_in_page(walk->offset);
61 }
62
skcipher_map_src(struct skcipher_walk * walk)63 static inline void skcipher_map_src(struct skcipher_walk *walk)
64 {
65 walk->src.virt.addr = skcipher_map(&walk->in);
66 }
67
skcipher_map_dst(struct skcipher_walk * walk)68 static inline void skcipher_map_dst(struct skcipher_walk *walk)
69 {
70 walk->dst.virt.addr = skcipher_map(&walk->out);
71 }
72
skcipher_unmap_src(struct skcipher_walk * walk)73 static inline void skcipher_unmap_src(struct skcipher_walk *walk)
74 {
75 skcipher_unmap(&walk->in, walk->src.virt.addr);
76 }
77
skcipher_unmap_dst(struct skcipher_walk * walk)78 static inline void skcipher_unmap_dst(struct skcipher_walk *walk)
79 {
80 skcipher_unmap(&walk->out, walk->dst.virt.addr);
81 }
82
skcipher_walk_gfp(struct skcipher_walk * walk)83 static inline gfp_t skcipher_walk_gfp(struct skcipher_walk *walk)
84 {
85 return walk->flags & SKCIPHER_WALK_SLEEP ? GFP_KERNEL : GFP_ATOMIC;
86 }
87
88 /* Get a spot of the specified length that does not straddle a page.
89 * The caller needs to ensure that there is enough space for this operation.
90 */
skcipher_get_spot(u8 * start,unsigned int len)91 static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
92 {
93 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
94
95 return max(start, end_page);
96 }
97
skcipher_done_slow(struct skcipher_walk * walk,unsigned int bsize)98 static void skcipher_done_slow(struct skcipher_walk *walk, unsigned int bsize)
99 {
100 u8 *addr;
101
102 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
103 addr = skcipher_get_spot(addr, bsize);
104 scatterwalk_copychunks(addr, &walk->out, bsize,
105 (walk->flags & SKCIPHER_WALK_PHYS) ? 2 : 1);
106 }
107
skcipher_walk_done(struct skcipher_walk * walk,int err)108 int skcipher_walk_done(struct skcipher_walk *walk, int err)
109 {
110 unsigned int n; /* bytes processed */
111 bool more;
112
113 if (unlikely(err < 0))
114 goto finish;
115
116 n = walk->nbytes - err;
117 walk->total -= n;
118 more = (walk->total != 0);
119
120 if (likely(!(walk->flags & (SKCIPHER_WALK_PHYS |
121 SKCIPHER_WALK_SLOW |
122 SKCIPHER_WALK_COPY |
123 SKCIPHER_WALK_DIFF)))) {
124 unmap_src:
125 skcipher_unmap_src(walk);
126 } else if (walk->flags & SKCIPHER_WALK_DIFF) {
127 skcipher_unmap_dst(walk);
128 goto unmap_src;
129 } else if (walk->flags & SKCIPHER_WALK_COPY) {
130 skcipher_map_dst(walk);
131 memcpy(walk->dst.virt.addr, walk->page, n);
132 skcipher_unmap_dst(walk);
133 } else if (unlikely(walk->flags & SKCIPHER_WALK_SLOW)) {
134 if (WARN_ON(err)) {
135 /* unexpected case; didn't process all bytes */
136 err = -EINVAL;
137 goto finish;
138 }
139 skcipher_done_slow(walk, n);
140 goto already_advanced;
141 }
142
143 scatterwalk_advance(&walk->in, n);
144 scatterwalk_advance(&walk->out, n);
145 already_advanced:
146 scatterwalk_done(&walk->in, 0, more);
147 scatterwalk_done(&walk->out, 1, more);
148
149 if (more) {
150 crypto_yield(walk->flags & SKCIPHER_WALK_SLEEP ?
151 CRYPTO_TFM_REQ_MAY_SLEEP : 0);
152 return skcipher_walk_next(walk);
153 }
154 err = 0;
155 finish:
156 walk->nbytes = 0;
157
158 /* Short-circuit for the common/fast path. */
159 if (!((unsigned long)walk->buffer | (unsigned long)walk->page))
160 goto out;
161
162 if (walk->flags & SKCIPHER_WALK_PHYS)
163 goto out;
164
165 if (walk->iv != walk->oiv)
166 memcpy(walk->oiv, walk->iv, walk->ivsize);
167 if (walk->buffer != walk->page)
168 kfree(walk->buffer);
169 if (walk->page)
170 free_page((unsigned long)walk->page);
171
172 out:
173 return err;
174 }
175 EXPORT_SYMBOL_GPL(skcipher_walk_done);
176
skcipher_walk_complete(struct skcipher_walk * walk,int err)177 void skcipher_walk_complete(struct skcipher_walk *walk, int err)
178 {
179 struct skcipher_walk_buffer *p, *tmp;
180
181 list_for_each_entry_safe(p, tmp, &walk->buffers, entry) {
182 u8 *data;
183
184 if (err)
185 goto done;
186
187 data = p->data;
188 if (!data) {
189 data = PTR_ALIGN(&p->buffer[0], walk->alignmask + 1);
190 data = skcipher_get_spot(data, walk->stride);
191 }
192
193 scatterwalk_copychunks(data, &p->dst, p->len, 1);
194
195 if (offset_in_page(p->data) + p->len + walk->stride >
196 PAGE_SIZE)
197 free_page((unsigned long)p->data);
198
199 done:
200 list_del(&p->entry);
201 kfree(p);
202 }
203
204 if (!err && walk->iv != walk->oiv)
205 memcpy(walk->oiv, walk->iv, walk->ivsize);
206 if (walk->buffer != walk->page)
207 kfree(walk->buffer);
208 if (walk->page)
209 free_page((unsigned long)walk->page);
210 }
211 EXPORT_SYMBOL_GPL(skcipher_walk_complete);
212
skcipher_queue_write(struct skcipher_walk * walk,struct skcipher_walk_buffer * p)213 static void skcipher_queue_write(struct skcipher_walk *walk,
214 struct skcipher_walk_buffer *p)
215 {
216 p->dst = walk->out;
217 list_add_tail(&p->entry, &walk->buffers);
218 }
219
skcipher_next_slow(struct skcipher_walk * walk,unsigned int bsize)220 static int skcipher_next_slow(struct skcipher_walk *walk, unsigned int bsize)
221 {
222 bool phys = walk->flags & SKCIPHER_WALK_PHYS;
223 unsigned alignmask = walk->alignmask;
224 struct skcipher_walk_buffer *p;
225 unsigned a;
226 unsigned n;
227 u8 *buffer;
228 void *v;
229
230 if (!phys) {
231 if (!walk->buffer)
232 walk->buffer = walk->page;
233 buffer = walk->buffer;
234 if (buffer)
235 goto ok;
236 }
237
238 /* Start with the minimum alignment of kmalloc. */
239 a = crypto_tfm_ctx_alignment() - 1;
240 n = bsize;
241
242 if (phys) {
243 /* Calculate the minimum alignment of p->buffer. */
244 a &= (sizeof(*p) ^ (sizeof(*p) - 1)) >> 1;
245 n += sizeof(*p);
246 }
247
248 /* Minimum size to align p->buffer by alignmask. */
249 n += alignmask & ~a;
250
251 /* Minimum size to ensure p->buffer does not straddle a page. */
252 n += (bsize - 1) & ~(alignmask | a);
253
254 v = kzalloc(n, skcipher_walk_gfp(walk));
255 if (!v)
256 return skcipher_walk_done(walk, -ENOMEM);
257
258 if (phys) {
259 p = v;
260 p->len = bsize;
261 skcipher_queue_write(walk, p);
262 buffer = p->buffer;
263 } else {
264 walk->buffer = v;
265 buffer = v;
266 }
267
268 ok:
269 walk->dst.virt.addr = PTR_ALIGN(buffer, alignmask + 1);
270 walk->dst.virt.addr = skcipher_get_spot(walk->dst.virt.addr, bsize);
271 walk->src.virt.addr = walk->dst.virt.addr;
272
273 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
274
275 walk->nbytes = bsize;
276 walk->flags |= SKCIPHER_WALK_SLOW;
277
278 return 0;
279 }
280
skcipher_next_copy(struct skcipher_walk * walk)281 static int skcipher_next_copy(struct skcipher_walk *walk)
282 {
283 struct skcipher_walk_buffer *p;
284 u8 *tmp = walk->page;
285
286 skcipher_map_src(walk);
287 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
288 skcipher_unmap_src(walk);
289
290 walk->src.virt.addr = tmp;
291 walk->dst.virt.addr = tmp;
292
293 if (!(walk->flags & SKCIPHER_WALK_PHYS))
294 return 0;
295
296 p = kmalloc(sizeof(*p), skcipher_walk_gfp(walk));
297 if (!p)
298 return -ENOMEM;
299
300 p->data = walk->page;
301 p->len = walk->nbytes;
302 skcipher_queue_write(walk, p);
303
304 if (offset_in_page(walk->page) + walk->nbytes + walk->stride >
305 PAGE_SIZE)
306 walk->page = NULL;
307 else
308 walk->page += walk->nbytes;
309
310 return 0;
311 }
312
skcipher_next_fast(struct skcipher_walk * walk)313 static int skcipher_next_fast(struct skcipher_walk *walk)
314 {
315 unsigned long diff;
316
317 walk->src.phys.page = scatterwalk_page(&walk->in);
318 walk->src.phys.offset = offset_in_page(walk->in.offset);
319 walk->dst.phys.page = scatterwalk_page(&walk->out);
320 walk->dst.phys.offset = offset_in_page(walk->out.offset);
321
322 if (walk->flags & SKCIPHER_WALK_PHYS)
323 return 0;
324
325 diff = walk->src.phys.offset - walk->dst.phys.offset;
326 diff |= walk->src.virt.page - walk->dst.virt.page;
327
328 skcipher_map_src(walk);
329 walk->dst.virt.addr = walk->src.virt.addr;
330
331 if (diff) {
332 walk->flags |= SKCIPHER_WALK_DIFF;
333 skcipher_map_dst(walk);
334 }
335
336 return 0;
337 }
338
skcipher_walk_next(struct skcipher_walk * walk)339 static int skcipher_walk_next(struct skcipher_walk *walk)
340 {
341 unsigned int bsize;
342 unsigned int n;
343 int err;
344
345 walk->flags &= ~(SKCIPHER_WALK_SLOW | SKCIPHER_WALK_COPY |
346 SKCIPHER_WALK_DIFF);
347
348 n = walk->total;
349 bsize = min(walk->stride, max(n, walk->blocksize));
350 n = scatterwalk_clamp(&walk->in, n);
351 n = scatterwalk_clamp(&walk->out, n);
352
353 if (unlikely(n < bsize)) {
354 if (unlikely(walk->total < walk->blocksize))
355 return skcipher_walk_done(walk, -EINVAL);
356
357 slow_path:
358 err = skcipher_next_slow(walk, bsize);
359 goto set_phys_lowmem;
360 }
361
362 if (unlikely((walk->in.offset | walk->out.offset) & walk->alignmask)) {
363 if (!walk->page) {
364 gfp_t gfp = skcipher_walk_gfp(walk);
365
366 walk->page = (void *)__get_free_page(gfp);
367 if (!walk->page)
368 goto slow_path;
369 }
370
371 walk->nbytes = min_t(unsigned, n,
372 PAGE_SIZE - offset_in_page(walk->page));
373 walk->flags |= SKCIPHER_WALK_COPY;
374 err = skcipher_next_copy(walk);
375 goto set_phys_lowmem;
376 }
377
378 walk->nbytes = n;
379
380 return skcipher_next_fast(walk);
381
382 set_phys_lowmem:
383 if (!err && (walk->flags & SKCIPHER_WALK_PHYS)) {
384 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
385 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
386 walk->src.phys.offset &= PAGE_SIZE - 1;
387 walk->dst.phys.offset &= PAGE_SIZE - 1;
388 }
389 return err;
390 }
391
skcipher_copy_iv(struct skcipher_walk * walk)392 static int skcipher_copy_iv(struct skcipher_walk *walk)
393 {
394 unsigned a = crypto_tfm_ctx_alignment() - 1;
395 unsigned alignmask = walk->alignmask;
396 unsigned ivsize = walk->ivsize;
397 unsigned bs = walk->stride;
398 unsigned aligned_bs;
399 unsigned size;
400 u8 *iv;
401
402 aligned_bs = ALIGN(bs, alignmask + 1);
403
404 /* Minimum size to align buffer by alignmask. */
405 size = alignmask & ~a;
406
407 if (walk->flags & SKCIPHER_WALK_PHYS)
408 size += ivsize;
409 else {
410 size += aligned_bs + ivsize;
411
412 /* Minimum size to ensure buffer does not straddle a page. */
413 size += (bs - 1) & ~(alignmask | a);
414 }
415
416 walk->buffer = kmalloc(size, skcipher_walk_gfp(walk));
417 if (!walk->buffer)
418 return -ENOMEM;
419
420 iv = PTR_ALIGN(walk->buffer, alignmask + 1);
421 iv = skcipher_get_spot(iv, bs) + aligned_bs;
422
423 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
424 return 0;
425 }
426
skcipher_walk_first(struct skcipher_walk * walk)427 static int skcipher_walk_first(struct skcipher_walk *walk)
428 {
429 if (WARN_ON_ONCE(in_irq()))
430 return -EDEADLK;
431
432 walk->buffer = NULL;
433 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
434 int err = skcipher_copy_iv(walk);
435 if (err)
436 return err;
437 }
438
439 walk->page = NULL;
440
441 return skcipher_walk_next(walk);
442 }
443
skcipher_walk_skcipher(struct skcipher_walk * walk,struct skcipher_request * req)444 static int skcipher_walk_skcipher(struct skcipher_walk *walk,
445 struct skcipher_request *req)
446 {
447 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
448
449 walk->total = req->cryptlen;
450 walk->nbytes = 0;
451 walk->iv = req->iv;
452 walk->oiv = req->iv;
453
454 if (unlikely(!walk->total))
455 return 0;
456
457 scatterwalk_start(&walk->in, req->src);
458 scatterwalk_start(&walk->out, req->dst);
459
460 walk->flags &= ~SKCIPHER_WALK_SLEEP;
461 walk->flags |= req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP ?
462 SKCIPHER_WALK_SLEEP : 0;
463
464 walk->blocksize = crypto_skcipher_blocksize(tfm);
465 walk->stride = crypto_skcipher_walksize(tfm);
466 walk->ivsize = crypto_skcipher_ivsize(tfm);
467 walk->alignmask = crypto_skcipher_alignmask(tfm);
468
469 return skcipher_walk_first(walk);
470 }
471
skcipher_walk_virt(struct skcipher_walk * walk,struct skcipher_request * req,bool atomic)472 int skcipher_walk_virt(struct skcipher_walk *walk,
473 struct skcipher_request *req, bool atomic)
474 {
475 int err;
476
477 walk->flags &= ~SKCIPHER_WALK_PHYS;
478
479 err = skcipher_walk_skcipher(walk, req);
480
481 walk->flags &= atomic ? ~SKCIPHER_WALK_SLEEP : ~0;
482
483 return err;
484 }
485 EXPORT_SYMBOL_GPL(skcipher_walk_virt);
486
skcipher_walk_atomise(struct skcipher_walk * walk)487 void skcipher_walk_atomise(struct skcipher_walk *walk)
488 {
489 walk->flags &= ~SKCIPHER_WALK_SLEEP;
490 }
491 EXPORT_SYMBOL_GPL(skcipher_walk_atomise);
492
skcipher_walk_async(struct skcipher_walk * walk,struct skcipher_request * req)493 int skcipher_walk_async(struct skcipher_walk *walk,
494 struct skcipher_request *req)
495 {
496 walk->flags |= SKCIPHER_WALK_PHYS;
497
498 INIT_LIST_HEAD(&walk->buffers);
499
500 return skcipher_walk_skcipher(walk, req);
501 }
502 EXPORT_SYMBOL_GPL(skcipher_walk_async);
503
skcipher_walk_aead_common(struct skcipher_walk * walk,struct aead_request * req,bool atomic)504 static int skcipher_walk_aead_common(struct skcipher_walk *walk,
505 struct aead_request *req, bool atomic)
506 {
507 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
508 int err;
509
510 walk->nbytes = 0;
511 walk->iv = req->iv;
512 walk->oiv = req->iv;
513
514 if (unlikely(!walk->total))
515 return 0;
516
517 walk->flags &= ~SKCIPHER_WALK_PHYS;
518
519 scatterwalk_start(&walk->in, req->src);
520 scatterwalk_start(&walk->out, req->dst);
521
522 scatterwalk_copychunks(NULL, &walk->in, req->assoclen, 2);
523 scatterwalk_copychunks(NULL, &walk->out, req->assoclen, 2);
524
525 scatterwalk_done(&walk->in, 0, walk->total);
526 scatterwalk_done(&walk->out, 0, walk->total);
527
528 if (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP)
529 walk->flags |= SKCIPHER_WALK_SLEEP;
530 else
531 walk->flags &= ~SKCIPHER_WALK_SLEEP;
532
533 walk->blocksize = crypto_aead_blocksize(tfm);
534 walk->stride = crypto_aead_chunksize(tfm);
535 walk->ivsize = crypto_aead_ivsize(tfm);
536 walk->alignmask = crypto_aead_alignmask(tfm);
537
538 err = skcipher_walk_first(walk);
539
540 if (atomic)
541 walk->flags &= ~SKCIPHER_WALK_SLEEP;
542
543 return err;
544 }
545
skcipher_walk_aead(struct skcipher_walk * walk,struct aead_request * req,bool atomic)546 int skcipher_walk_aead(struct skcipher_walk *walk, struct aead_request *req,
547 bool atomic)
548 {
549 walk->total = req->cryptlen;
550
551 return skcipher_walk_aead_common(walk, req, atomic);
552 }
553 EXPORT_SYMBOL_GPL(skcipher_walk_aead);
554
skcipher_walk_aead_encrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)555 int skcipher_walk_aead_encrypt(struct skcipher_walk *walk,
556 struct aead_request *req, bool atomic)
557 {
558 walk->total = req->cryptlen;
559
560 return skcipher_walk_aead_common(walk, req, atomic);
561 }
562 EXPORT_SYMBOL_GPL(skcipher_walk_aead_encrypt);
563
skcipher_walk_aead_decrypt(struct skcipher_walk * walk,struct aead_request * req,bool atomic)564 int skcipher_walk_aead_decrypt(struct skcipher_walk *walk,
565 struct aead_request *req, bool atomic)
566 {
567 struct crypto_aead *tfm = crypto_aead_reqtfm(req);
568
569 walk->total = req->cryptlen - crypto_aead_authsize(tfm);
570
571 return skcipher_walk_aead_common(walk, req, atomic);
572 }
573 EXPORT_SYMBOL_GPL(skcipher_walk_aead_decrypt);
574
crypto_skcipher_extsize(struct crypto_alg * alg)575 static unsigned int crypto_skcipher_extsize(struct crypto_alg *alg)
576 {
577 if (alg->cra_type == &crypto_blkcipher_type)
578 return sizeof(struct crypto_blkcipher *);
579
580 if (alg->cra_type == &crypto_ablkcipher_type ||
581 alg->cra_type == &crypto_givcipher_type)
582 return sizeof(struct crypto_ablkcipher *);
583
584 return crypto_alg_extsize(alg);
585 }
586
skcipher_setkey_blkcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)587 static int skcipher_setkey_blkcipher(struct crypto_skcipher *tfm,
588 const u8 *key, unsigned int keylen)
589 {
590 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
591 struct crypto_blkcipher *blkcipher = *ctx;
592 int err;
593
594 crypto_blkcipher_clear_flags(blkcipher, ~0);
595 crypto_blkcipher_set_flags(blkcipher, crypto_skcipher_get_flags(tfm) &
596 CRYPTO_TFM_REQ_MASK);
597 err = crypto_blkcipher_setkey(blkcipher, key, keylen);
598 crypto_skcipher_set_flags(tfm, crypto_blkcipher_get_flags(blkcipher) &
599 CRYPTO_TFM_RES_MASK);
600 if (err)
601 return err;
602
603 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
604 return 0;
605 }
606
skcipher_crypt_blkcipher(struct skcipher_request * req,int (* crypt)(struct blkcipher_desc *,struct scatterlist *,struct scatterlist *,unsigned int))607 static int skcipher_crypt_blkcipher(struct skcipher_request *req,
608 int (*crypt)(struct blkcipher_desc *,
609 struct scatterlist *,
610 struct scatterlist *,
611 unsigned int))
612 {
613 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
614 struct crypto_blkcipher **ctx = crypto_skcipher_ctx(tfm);
615 struct blkcipher_desc desc = {
616 .tfm = *ctx,
617 .info = req->iv,
618 .flags = req->base.flags,
619 };
620
621
622 return crypt(&desc, req->dst, req->src, req->cryptlen);
623 }
624
skcipher_encrypt_blkcipher(struct skcipher_request * req)625 static int skcipher_encrypt_blkcipher(struct skcipher_request *req)
626 {
627 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
628 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
629 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
630
631 return skcipher_crypt_blkcipher(req, alg->encrypt);
632 }
633
skcipher_decrypt_blkcipher(struct skcipher_request * req)634 static int skcipher_decrypt_blkcipher(struct skcipher_request *req)
635 {
636 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
637 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
638 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
639
640 return skcipher_crypt_blkcipher(req, alg->decrypt);
641 }
642
crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm * tfm)643 static void crypto_exit_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
644 {
645 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
646
647 crypto_free_blkcipher(*ctx);
648 }
649
crypto_init_skcipher_ops_blkcipher(struct crypto_tfm * tfm)650 static int crypto_init_skcipher_ops_blkcipher(struct crypto_tfm *tfm)
651 {
652 struct crypto_alg *calg = tfm->__crt_alg;
653 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
654 struct crypto_blkcipher **ctx = crypto_tfm_ctx(tfm);
655 struct crypto_blkcipher *blkcipher;
656 struct crypto_tfm *btfm;
657
658 if (!crypto_mod_get(calg))
659 return -EAGAIN;
660
661 btfm = __crypto_alloc_tfm(calg, CRYPTO_ALG_TYPE_BLKCIPHER,
662 CRYPTO_ALG_TYPE_MASK);
663 if (IS_ERR(btfm)) {
664 crypto_mod_put(calg);
665 return PTR_ERR(btfm);
666 }
667
668 blkcipher = __crypto_blkcipher_cast(btfm);
669 *ctx = blkcipher;
670 tfm->exit = crypto_exit_skcipher_ops_blkcipher;
671
672 skcipher->setkey = skcipher_setkey_blkcipher;
673 skcipher->encrypt = skcipher_encrypt_blkcipher;
674 skcipher->decrypt = skcipher_decrypt_blkcipher;
675
676 skcipher->ivsize = crypto_blkcipher_ivsize(blkcipher);
677 skcipher->keysize = calg->cra_blkcipher.max_keysize;
678
679 if (skcipher->keysize)
680 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
681
682 return 0;
683 }
684
skcipher_setkey_ablkcipher(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)685 static int skcipher_setkey_ablkcipher(struct crypto_skcipher *tfm,
686 const u8 *key, unsigned int keylen)
687 {
688 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
689 struct crypto_ablkcipher *ablkcipher = *ctx;
690 int err;
691
692 crypto_ablkcipher_clear_flags(ablkcipher, ~0);
693 crypto_ablkcipher_set_flags(ablkcipher,
694 crypto_skcipher_get_flags(tfm) &
695 CRYPTO_TFM_REQ_MASK);
696 err = crypto_ablkcipher_setkey(ablkcipher, key, keylen);
697 crypto_skcipher_set_flags(tfm,
698 crypto_ablkcipher_get_flags(ablkcipher) &
699 CRYPTO_TFM_RES_MASK);
700 if (err)
701 return err;
702
703 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
704 return 0;
705 }
706
skcipher_crypt_ablkcipher(struct skcipher_request * req,int (* crypt)(struct ablkcipher_request *))707 static int skcipher_crypt_ablkcipher(struct skcipher_request *req,
708 int (*crypt)(struct ablkcipher_request *))
709 {
710 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
711 struct crypto_ablkcipher **ctx = crypto_skcipher_ctx(tfm);
712 struct ablkcipher_request *subreq = skcipher_request_ctx(req);
713
714 ablkcipher_request_set_tfm(subreq, *ctx);
715 ablkcipher_request_set_callback(subreq, skcipher_request_flags(req),
716 req->base.complete, req->base.data);
717 ablkcipher_request_set_crypt(subreq, req->src, req->dst, req->cryptlen,
718 req->iv);
719
720 return crypt(subreq);
721 }
722
skcipher_encrypt_ablkcipher(struct skcipher_request * req)723 static int skcipher_encrypt_ablkcipher(struct skcipher_request *req)
724 {
725 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
726 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
727 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
728
729 return skcipher_crypt_ablkcipher(req, alg->encrypt);
730 }
731
skcipher_decrypt_ablkcipher(struct skcipher_request * req)732 static int skcipher_decrypt_ablkcipher(struct skcipher_request *req)
733 {
734 struct crypto_skcipher *skcipher = crypto_skcipher_reqtfm(req);
735 struct crypto_tfm *tfm = crypto_skcipher_tfm(skcipher);
736 struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher;
737
738 return skcipher_crypt_ablkcipher(req, alg->decrypt);
739 }
740
crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm * tfm)741 static void crypto_exit_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
742 {
743 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
744
745 crypto_free_ablkcipher(*ctx);
746 }
747
crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm * tfm)748 static int crypto_init_skcipher_ops_ablkcipher(struct crypto_tfm *tfm)
749 {
750 struct crypto_alg *calg = tfm->__crt_alg;
751 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
752 struct crypto_ablkcipher **ctx = crypto_tfm_ctx(tfm);
753 struct crypto_ablkcipher *ablkcipher;
754 struct crypto_tfm *abtfm;
755
756 if (!crypto_mod_get(calg))
757 return -EAGAIN;
758
759 abtfm = __crypto_alloc_tfm(calg, 0, 0);
760 if (IS_ERR(abtfm)) {
761 crypto_mod_put(calg);
762 return PTR_ERR(abtfm);
763 }
764
765 ablkcipher = __crypto_ablkcipher_cast(abtfm);
766 *ctx = ablkcipher;
767 tfm->exit = crypto_exit_skcipher_ops_ablkcipher;
768
769 skcipher->setkey = skcipher_setkey_ablkcipher;
770 skcipher->encrypt = skcipher_encrypt_ablkcipher;
771 skcipher->decrypt = skcipher_decrypt_ablkcipher;
772
773 skcipher->ivsize = crypto_ablkcipher_ivsize(ablkcipher);
774 skcipher->reqsize = crypto_ablkcipher_reqsize(ablkcipher) +
775 sizeof(struct ablkcipher_request);
776 skcipher->keysize = calg->cra_ablkcipher.max_keysize;
777
778 if (skcipher->keysize)
779 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
780
781 return 0;
782 }
783
skcipher_setkey_unaligned(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)784 static int skcipher_setkey_unaligned(struct crypto_skcipher *tfm,
785 const u8 *key, unsigned int keylen)
786 {
787 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
788 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
789 u8 *buffer, *alignbuffer;
790 unsigned long absize;
791 int ret;
792
793 absize = keylen + alignmask;
794 buffer = kmalloc(absize, GFP_ATOMIC);
795 if (!buffer)
796 return -ENOMEM;
797
798 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
799 memcpy(alignbuffer, key, keylen);
800 ret = cipher->setkey(tfm, alignbuffer, keylen);
801 kzfree(buffer);
802 return ret;
803 }
804
skcipher_setkey(struct crypto_skcipher * tfm,const u8 * key,unsigned int keylen)805 static int skcipher_setkey(struct crypto_skcipher *tfm, const u8 *key,
806 unsigned int keylen)
807 {
808 struct skcipher_alg *cipher = crypto_skcipher_alg(tfm);
809 unsigned long alignmask = crypto_skcipher_alignmask(tfm);
810 int err;
811
812 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
813 crypto_skcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
814 return -EINVAL;
815 }
816
817 if ((unsigned long)key & alignmask)
818 err = skcipher_setkey_unaligned(tfm, key, keylen);
819 else
820 err = cipher->setkey(tfm, key, keylen);
821
822 if (err)
823 return err;
824
825 crypto_skcipher_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
826 return 0;
827 }
828
crypto_skcipher_exit_tfm(struct crypto_tfm * tfm)829 static void crypto_skcipher_exit_tfm(struct crypto_tfm *tfm)
830 {
831 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
832 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
833
834 alg->exit(skcipher);
835 }
836
crypto_skcipher_init_tfm(struct crypto_tfm * tfm)837 static int crypto_skcipher_init_tfm(struct crypto_tfm *tfm)
838 {
839 struct crypto_skcipher *skcipher = __crypto_skcipher_cast(tfm);
840 struct skcipher_alg *alg = crypto_skcipher_alg(skcipher);
841
842 if (tfm->__crt_alg->cra_type == &crypto_blkcipher_type)
843 return crypto_init_skcipher_ops_blkcipher(tfm);
844
845 if (tfm->__crt_alg->cra_type == &crypto_ablkcipher_type ||
846 tfm->__crt_alg->cra_type == &crypto_givcipher_type)
847 return crypto_init_skcipher_ops_ablkcipher(tfm);
848
849 skcipher->setkey = skcipher_setkey;
850 skcipher->encrypt = alg->encrypt;
851 skcipher->decrypt = alg->decrypt;
852 skcipher->ivsize = alg->ivsize;
853 skcipher->keysize = alg->max_keysize;
854
855 if (skcipher->keysize)
856 crypto_skcipher_set_flags(skcipher, CRYPTO_TFM_NEED_KEY);
857
858 if (alg->exit)
859 skcipher->base.exit = crypto_skcipher_exit_tfm;
860
861 if (alg->init)
862 return alg->init(skcipher);
863
864 return 0;
865 }
866
crypto_skcipher_free_instance(struct crypto_instance * inst)867 static void crypto_skcipher_free_instance(struct crypto_instance *inst)
868 {
869 struct skcipher_instance *skcipher =
870 container_of(inst, struct skcipher_instance, s.base);
871
872 skcipher->free(skcipher);
873 }
874
875 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
876 __maybe_unused;
crypto_skcipher_show(struct seq_file * m,struct crypto_alg * alg)877 static void crypto_skcipher_show(struct seq_file *m, struct crypto_alg *alg)
878 {
879 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
880 base);
881
882 seq_printf(m, "type : skcipher\n");
883 seq_printf(m, "async : %s\n",
884 alg->cra_flags & CRYPTO_ALG_ASYNC ? "yes" : "no");
885 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
886 seq_printf(m, "min keysize : %u\n", skcipher->min_keysize);
887 seq_printf(m, "max keysize : %u\n", skcipher->max_keysize);
888 seq_printf(m, "ivsize : %u\n", skcipher->ivsize);
889 seq_printf(m, "chunksize : %u\n", skcipher->chunksize);
890 seq_printf(m, "walksize : %u\n", skcipher->walksize);
891 }
892
893 #ifdef CONFIG_NET
crypto_skcipher_report(struct sk_buff * skb,struct crypto_alg * alg)894 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
895 {
896 struct crypto_report_blkcipher rblkcipher;
897 struct skcipher_alg *skcipher = container_of(alg, struct skcipher_alg,
898 base);
899
900 strncpy(rblkcipher.type, "skcipher", sizeof(rblkcipher.type));
901 strncpy(rblkcipher.geniv, "<none>", sizeof(rblkcipher.geniv));
902
903 rblkcipher.blocksize = alg->cra_blocksize;
904 rblkcipher.min_keysize = skcipher->min_keysize;
905 rblkcipher.max_keysize = skcipher->max_keysize;
906 rblkcipher.ivsize = skcipher->ivsize;
907
908 if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
909 sizeof(struct crypto_report_blkcipher), &rblkcipher))
910 goto nla_put_failure;
911 return 0;
912
913 nla_put_failure:
914 return -EMSGSIZE;
915 }
916 #else
crypto_skcipher_report(struct sk_buff * skb,struct crypto_alg * alg)917 static int crypto_skcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
918 {
919 return -ENOSYS;
920 }
921 #endif
922
923 static const struct crypto_type crypto_skcipher_type2 = {
924 .extsize = crypto_skcipher_extsize,
925 .init_tfm = crypto_skcipher_init_tfm,
926 .free = crypto_skcipher_free_instance,
927 #ifdef CONFIG_PROC_FS
928 .show = crypto_skcipher_show,
929 #endif
930 .report = crypto_skcipher_report,
931 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
932 .maskset = CRYPTO_ALG_TYPE_BLKCIPHER_MASK,
933 .type = CRYPTO_ALG_TYPE_SKCIPHER,
934 .tfmsize = offsetof(struct crypto_skcipher, base),
935 };
936
crypto_grab_skcipher(struct crypto_skcipher_spawn * spawn,const char * name,u32 type,u32 mask)937 int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn,
938 const char *name, u32 type, u32 mask)
939 {
940 spawn->base.frontend = &crypto_skcipher_type2;
941 return crypto_grab_spawn(&spawn->base, name, type, mask);
942 }
943 EXPORT_SYMBOL_GPL(crypto_grab_skcipher);
944
crypto_alloc_skcipher(const char * alg_name,u32 type,u32 mask)945 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
946 u32 type, u32 mask)
947 {
948 return crypto_alloc_tfm(alg_name, &crypto_skcipher_type2, type, mask);
949 }
950 EXPORT_SYMBOL_GPL(crypto_alloc_skcipher);
951
crypto_has_skcipher2(const char * alg_name,u32 type,u32 mask)952 int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask)
953 {
954 return crypto_type_has_alg(alg_name, &crypto_skcipher_type2,
955 type, mask);
956 }
957 EXPORT_SYMBOL_GPL(crypto_has_skcipher2);
958
skcipher_prepare_alg(struct skcipher_alg * alg)959 static int skcipher_prepare_alg(struct skcipher_alg *alg)
960 {
961 struct crypto_alg *base = &alg->base;
962
963 if (alg->ivsize > PAGE_SIZE / 8 || alg->chunksize > PAGE_SIZE / 8 ||
964 alg->walksize > PAGE_SIZE / 8)
965 return -EINVAL;
966
967 if (!alg->chunksize)
968 alg->chunksize = base->cra_blocksize;
969 if (!alg->walksize)
970 alg->walksize = alg->chunksize;
971
972 base->cra_type = &crypto_skcipher_type2;
973 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
974 base->cra_flags |= CRYPTO_ALG_TYPE_SKCIPHER;
975
976 return 0;
977 }
978
crypto_register_skcipher(struct skcipher_alg * alg)979 int crypto_register_skcipher(struct skcipher_alg *alg)
980 {
981 struct crypto_alg *base = &alg->base;
982 int err;
983
984 err = skcipher_prepare_alg(alg);
985 if (err)
986 return err;
987
988 return crypto_register_alg(base);
989 }
990 EXPORT_SYMBOL_GPL(crypto_register_skcipher);
991
crypto_unregister_skcipher(struct skcipher_alg * alg)992 void crypto_unregister_skcipher(struct skcipher_alg *alg)
993 {
994 crypto_unregister_alg(&alg->base);
995 }
996 EXPORT_SYMBOL_GPL(crypto_unregister_skcipher);
997
crypto_register_skciphers(struct skcipher_alg * algs,int count)998 int crypto_register_skciphers(struct skcipher_alg *algs, int count)
999 {
1000 int i, ret;
1001
1002 for (i = 0; i < count; i++) {
1003 ret = crypto_register_skcipher(&algs[i]);
1004 if (ret)
1005 goto err;
1006 }
1007
1008 return 0;
1009
1010 err:
1011 for (--i; i >= 0; --i)
1012 crypto_unregister_skcipher(&algs[i]);
1013
1014 return ret;
1015 }
1016 EXPORT_SYMBOL_GPL(crypto_register_skciphers);
1017
crypto_unregister_skciphers(struct skcipher_alg * algs,int count)1018 void crypto_unregister_skciphers(struct skcipher_alg *algs, int count)
1019 {
1020 int i;
1021
1022 for (i = count - 1; i >= 0; --i)
1023 crypto_unregister_skcipher(&algs[i]);
1024 }
1025 EXPORT_SYMBOL_GPL(crypto_unregister_skciphers);
1026
skcipher_register_instance(struct crypto_template * tmpl,struct skcipher_instance * inst)1027 int skcipher_register_instance(struct crypto_template *tmpl,
1028 struct skcipher_instance *inst)
1029 {
1030 int err;
1031
1032 err = skcipher_prepare_alg(&inst->alg);
1033 if (err)
1034 return err;
1035
1036 return crypto_register_instance(tmpl, skcipher_crypto_instance(inst));
1037 }
1038 EXPORT_SYMBOL_GPL(skcipher_register_instance);
1039
1040 MODULE_LICENSE("GPL");
1041 MODULE_DESCRIPTION("Symmetric key cipher type");
1042
