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1/*
2 * Block chaining 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) 2006 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/aead.h>
18#include <crypto/internal/skcipher.h>
19#include <crypto/scatterwalk.h>
20#include <linux/errno.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/seq_file.h>
24#include <linux/slab.h>
25#include <linux/string.h>
26#include <linux/cryptouser.h>
27#include <linux/compiler.h>
28#include <net/netlink.h>
29
30#include "internal.h"
31
32enum {
33 BLKCIPHER_WALK_PHYS = 1 << 0,
34 BLKCIPHER_WALK_SLOW = 1 << 1,
35 BLKCIPHER_WALK_COPY = 1 << 2,
36 BLKCIPHER_WALK_DIFF = 1 << 3,
37};
38
39static int blkcipher_walk_next(struct blkcipher_desc *desc,
40 struct blkcipher_walk *walk);
41static int blkcipher_walk_first(struct blkcipher_desc *desc,
42 struct blkcipher_walk *walk);
43
44static inline void blkcipher_map_src(struct blkcipher_walk *walk)
45{
46 walk->src.virt.addr = scatterwalk_map(&walk->in);
47}
48
49static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
50{
51 walk->dst.virt.addr = scatterwalk_map(&walk->out);
52}
53
54static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
55{
56 scatterwalk_unmap(walk->src.virt.addr);
57}
58
59static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
60{
61 scatterwalk_unmap(walk->dst.virt.addr);
62}
63
64/* Get a spot of the specified length that does not straddle a page.
65 * The caller needs to ensure that there is enough space for this operation.
66 */
67static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len)
68{
69 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
70 return max(start, end_page);
71}
72
73static inline unsigned int blkcipher_done_slow(struct blkcipher_walk *walk,
74 unsigned int bsize)
75{
76 u8 *addr;
77
78 addr = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
79 addr = blkcipher_get_spot(addr, bsize);
80 scatterwalk_copychunks(addr, &walk->out, bsize, 1);
81 return bsize;
82}
83
84static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk,
85 unsigned int n)
86{
87 if (walk->flags & BLKCIPHER_WALK_COPY) {
88 blkcipher_map_dst(walk);
89 memcpy(walk->dst.virt.addr, walk->page, n);
90 blkcipher_unmap_dst(walk);
91 } else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
92 if (walk->flags & BLKCIPHER_WALK_DIFF)
93 blkcipher_unmap_dst(walk);
94 blkcipher_unmap_src(walk);
95 }
96
97 scatterwalk_advance(&walk->in, n);
98 scatterwalk_advance(&walk->out, n);
99
100 return n;
101}
102
103int blkcipher_walk_done(struct blkcipher_desc *desc,
104 struct blkcipher_walk *walk, int err)
105{
106 unsigned int nbytes = 0;
107
108 if (likely(err >= 0)) {
109 unsigned int n = walk->nbytes - err;
110
111 if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
112 n = blkcipher_done_fast(walk, n);
113 else if (WARN_ON(err)) {
114 err = -EINVAL;
115 goto err;
116 } else
117 n = blkcipher_done_slow(walk, n);
118
119 nbytes = walk->total - n;
120 err = 0;
121 }
122
123 scatterwalk_done(&walk->in, 0, nbytes);
124 scatterwalk_done(&walk->out, 1, nbytes);
125
126err:
127 walk->total = nbytes;
128 walk->nbytes = nbytes;
129
130 if (nbytes) {
131 crypto_yield(desc->flags);
132 return blkcipher_walk_next(desc, walk);
133 }
134
135 if (walk->iv != desc->info)
136 memcpy(desc->info, walk->iv, walk->ivsize);
137 if (walk->buffer != walk->page)
138 kfree(walk->buffer);
139 if (walk->page)
140 free_page((unsigned long)walk->page);
141
142 return err;
143}
144EXPORT_SYMBOL_GPL(blkcipher_walk_done);
145
146static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
147 struct blkcipher_walk *walk,
148 unsigned int bsize,
149 unsigned int alignmask)
150{
151 unsigned int n;
152 unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
153
154 if (walk->buffer)
155 goto ok;
156
157 walk->buffer = walk->page;
158 if (walk->buffer)
159 goto ok;
160
161 n = aligned_bsize * 3 - (alignmask + 1) +
162 (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
163 walk->buffer = kmalloc(n, GFP_ATOMIC);
164 if (!walk->buffer)
165 return blkcipher_walk_done(desc, walk, -ENOMEM);
166
167ok:
168 walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
169 alignmask + 1);
170 walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
171 walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
172 aligned_bsize, bsize);
173
174 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
175
176 walk->nbytes = bsize;
177 walk->flags |= BLKCIPHER_WALK_SLOW;
178
179 return 0;
180}
181
182static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
183{
184 u8 *tmp = walk->page;
185
186 blkcipher_map_src(walk);
187 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
188 blkcipher_unmap_src(walk);
189
190 walk->src.virt.addr = tmp;
191 walk->dst.virt.addr = tmp;
192
193 return 0;
194}
195
196static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
197 struct blkcipher_walk *walk)
198{
199 unsigned long diff;
200
201 walk->src.phys.page = scatterwalk_page(&walk->in);
202 walk->src.phys.offset = offset_in_page(walk->in.offset);
203 walk->dst.phys.page = scatterwalk_page(&walk->out);
204 walk->dst.phys.offset = offset_in_page(walk->out.offset);
205
206 if (walk->flags & BLKCIPHER_WALK_PHYS)
207 return 0;
208
209 diff = walk->src.phys.offset - walk->dst.phys.offset;
210 diff |= walk->src.virt.page - walk->dst.virt.page;
211
212 blkcipher_map_src(walk);
213 walk->dst.virt.addr = walk->src.virt.addr;
214
215 if (diff) {
216 walk->flags |= BLKCIPHER_WALK_DIFF;
217 blkcipher_map_dst(walk);
218 }
219
220 return 0;
221}
222
223static int blkcipher_walk_next(struct blkcipher_desc *desc,
224 struct blkcipher_walk *walk)
225{
226 unsigned int bsize;
227 unsigned int n;
228 int err;
229
230 n = walk->total;
231 if (unlikely(n < walk->cipher_blocksize)) {
232 desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
233 return blkcipher_walk_done(desc, walk, -EINVAL);
234 }
235
236 bsize = min(walk->walk_blocksize, n);
237
238 walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
239 BLKCIPHER_WALK_DIFF);
240 if (!scatterwalk_aligned(&walk->in, walk->alignmask) ||
241 !scatterwalk_aligned(&walk->out, walk->alignmask)) {
242 walk->flags |= BLKCIPHER_WALK_COPY;
243 if (!walk->page) {
244 walk->page = (void *)__get_free_page(GFP_ATOMIC);
245 if (!walk->page)
246 n = 0;
247 }
248 }
249
250 n = scatterwalk_clamp(&walk->in, n);
251 n = scatterwalk_clamp(&walk->out, n);
252
253 if (unlikely(n < bsize)) {
254 err = blkcipher_next_slow(desc, walk, bsize, walk->alignmask);
255 goto set_phys_lowmem;
256 }
257
258 walk->nbytes = n;
259 if (walk->flags & BLKCIPHER_WALK_COPY) {
260 err = blkcipher_next_copy(walk);
261 goto set_phys_lowmem;
262 }
263
264 return blkcipher_next_fast(desc, walk);
265
266set_phys_lowmem:
267 if (walk->flags & BLKCIPHER_WALK_PHYS) {
268 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
269 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
270 walk->src.phys.offset &= PAGE_SIZE - 1;
271 walk->dst.phys.offset &= PAGE_SIZE - 1;
272 }
273 return err;
274}
275
276static inline int blkcipher_copy_iv(struct blkcipher_walk *walk)
277{
278 unsigned bs = walk->walk_blocksize;
279 unsigned aligned_bs = ALIGN(bs, walk->alignmask + 1);
280 unsigned int size = aligned_bs * 2 +
281 walk->ivsize + max(aligned_bs, walk->ivsize) -
282 (walk->alignmask + 1);
283 u8 *iv;
284
285 size += walk->alignmask & ~(crypto_tfm_ctx_alignment() - 1);
286 walk->buffer = kmalloc(size, GFP_ATOMIC);
287 if (!walk->buffer)
288 return -ENOMEM;
289
290 iv = (u8 *)ALIGN((unsigned long)walk->buffer, walk->alignmask + 1);
291 iv = blkcipher_get_spot(iv, bs) + aligned_bs;
292 iv = blkcipher_get_spot(iv, bs) + aligned_bs;
293 iv = blkcipher_get_spot(iv, walk->ivsize);
294
295 walk->iv = memcpy(iv, walk->iv, walk->ivsize);
296 return 0;
297}
298
299int blkcipher_walk_virt(struct blkcipher_desc *desc,
300 struct blkcipher_walk *walk)
301{
302 walk->flags &= ~BLKCIPHER_WALK_PHYS;
303 walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
304 walk->cipher_blocksize = walk->walk_blocksize;
305 walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
306 walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
307 return blkcipher_walk_first(desc, walk);
308}
309EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
310
311int blkcipher_walk_phys(struct blkcipher_desc *desc,
312 struct blkcipher_walk *walk)
313{
314 walk->flags |= BLKCIPHER_WALK_PHYS;
315 walk->walk_blocksize = crypto_blkcipher_blocksize(desc->tfm);
316 walk->cipher_blocksize = walk->walk_blocksize;
317 walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
318 walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
319 return blkcipher_walk_first(desc, walk);
320}
321EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
322
323static int blkcipher_walk_first(struct blkcipher_desc *desc,
324 struct blkcipher_walk *walk)
325{
326 if (WARN_ON_ONCE(in_irq()))
327 return -EDEADLK;
328
329 walk->iv = desc->info;
330 walk->nbytes = walk->total;
331 if (unlikely(!walk->total))
332 return 0;
333
334 walk->buffer = NULL;
335 if (unlikely(((unsigned long)walk->iv & walk->alignmask))) {
336 int err = blkcipher_copy_iv(walk);
337 if (err)
338 return err;
339 }
340
341 scatterwalk_start(&walk->in, walk->in.sg);
342 scatterwalk_start(&walk->out, walk->out.sg);
343 walk->page = NULL;
344
345 return blkcipher_walk_next(desc, walk);
346}
347
348int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
349 struct blkcipher_walk *walk,
350 unsigned int blocksize)
351{
352 walk->flags &= ~BLKCIPHER_WALK_PHYS;
353 walk->walk_blocksize = blocksize;
354 walk->cipher_blocksize = crypto_blkcipher_blocksize(desc->tfm);
355 walk->ivsize = crypto_blkcipher_ivsize(desc->tfm);
356 walk->alignmask = crypto_blkcipher_alignmask(desc->tfm);
357 return blkcipher_walk_first(desc, walk);
358}
359EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);
360
361int blkcipher_aead_walk_virt_block(struct blkcipher_desc *desc,
362 struct blkcipher_walk *walk,
363 struct crypto_aead *tfm,
364 unsigned int blocksize)
365{
366 walk->flags &= ~BLKCIPHER_WALK_PHYS;
367 walk->walk_blocksize = blocksize;
368 walk->cipher_blocksize = crypto_aead_blocksize(tfm);
369 walk->ivsize = crypto_aead_ivsize(tfm);
370 walk->alignmask = crypto_aead_alignmask(tfm);
371 return blkcipher_walk_first(desc, walk);
372}
373EXPORT_SYMBOL_GPL(blkcipher_aead_walk_virt_block);
374
375static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
376 unsigned int keylen)
377{
378 struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
379 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
380 int ret;
381 u8 *buffer, *alignbuffer;
382 unsigned long absize;
383
384 absize = keylen + alignmask;
385 buffer = kmalloc(absize, GFP_ATOMIC);
386 if (!buffer)
387 return -ENOMEM;
388
389 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
390 memcpy(alignbuffer, key, keylen);
391 ret = cipher->setkey(tfm, alignbuffer, keylen);
392 memset(alignbuffer, 0, keylen);
393 kfree(buffer);
394 return ret;
395}
396
397static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
398{
399 struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
400 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
401
402 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
403 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
404 return -EINVAL;
405 }
406
407 if ((unsigned long)key & alignmask)
408 return setkey_unaligned(tfm, key, keylen);
409
410 return cipher->setkey(tfm, key, keylen);
411}
412
413static int async_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
414 unsigned int keylen)
415{
416 return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
417}
418
419static int async_encrypt(struct ablkcipher_request *req)
420{
421 struct crypto_tfm *tfm = req->base.tfm;
422 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
423 struct blkcipher_desc desc = {
424 .tfm = __crypto_blkcipher_cast(tfm),
425 .info = req->info,
426 .flags = req->base.flags,
427 };
428
429
430 return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
431}
432
433static int async_decrypt(struct ablkcipher_request *req)
434{
435 struct crypto_tfm *tfm = req->base.tfm;
436 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
437 struct blkcipher_desc desc = {
438 .tfm = __crypto_blkcipher_cast(tfm),
439 .info = req->info,
440 .flags = req->base.flags,
441 };
442
443 return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
444}
445
446static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
447 u32 mask)
448{
449 struct blkcipher_alg *cipher = &alg->cra_blkcipher;
450 unsigned int len = alg->cra_ctxsize;
451
452 if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
453 cipher->ivsize) {
454 len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
455 len += cipher->ivsize;
456 }
457
458 return len;
459}
460
461static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
462{
463 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
464 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
465
466 crt->setkey = async_setkey;
467 crt->encrypt = async_encrypt;
468 crt->decrypt = async_decrypt;
469 crt->base = __crypto_ablkcipher_cast(tfm);
470 crt->ivsize = alg->ivsize;
471
472 return 0;
473}
474
475static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
476{
477 struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
478 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
479 unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
480 unsigned long addr;
481
482 crt->setkey = setkey;
483 crt->encrypt = alg->encrypt;
484 crt->decrypt = alg->decrypt;
485
486 addr = (unsigned long)crypto_tfm_ctx(tfm);
487 addr = ALIGN(addr, align);
488 addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
489 crt->iv = (void *)addr;
490
491 return 0;
492}
493
494static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
495{
496 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
497
498 if (alg->ivsize > PAGE_SIZE / 8)
499 return -EINVAL;
500
501 if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
502 return crypto_init_blkcipher_ops_sync(tfm);
503 else
504 return crypto_init_blkcipher_ops_async(tfm);
505}
506
507#ifdef CONFIG_NET
508static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
509{
510 struct crypto_report_blkcipher rblkcipher;
511
512 strncpy(rblkcipher.type, "blkcipher", sizeof(rblkcipher.type));
513 strncpy(rblkcipher.geniv, alg->cra_blkcipher.geniv ?: "<default>",
514 sizeof(rblkcipher.geniv));
515
516 rblkcipher.blocksize = alg->cra_blocksize;
517 rblkcipher.min_keysize = alg->cra_blkcipher.min_keysize;
518 rblkcipher.max_keysize = alg->cra_blkcipher.max_keysize;
519 rblkcipher.ivsize = alg->cra_blkcipher.ivsize;
520
521 if (nla_put(skb, CRYPTOCFGA_REPORT_BLKCIPHER,
522 sizeof(struct crypto_report_blkcipher), &rblkcipher))
523 goto nla_put_failure;
524 return 0;
525
526nla_put_failure:
527 return -EMSGSIZE;
528}
529#else
530static int crypto_blkcipher_report(struct sk_buff *skb, struct crypto_alg *alg)
531{
532 return -ENOSYS;
533}
534#endif
535
536static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
537 __maybe_unused;
538static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
539{
540 seq_printf(m, "type : blkcipher\n");
541 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
542 seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize);
543 seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize);
544 seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize);
545 seq_printf(m, "geniv : %s\n", alg->cra_blkcipher.geniv ?:
546 "<default>");
547}
548
549const struct crypto_type crypto_blkcipher_type = {
550 .ctxsize = crypto_blkcipher_ctxsize,
551 .init = crypto_init_blkcipher_ops,
552#ifdef CONFIG_PROC_FS
553 .show = crypto_blkcipher_show,
554#endif
555 .report = crypto_blkcipher_report,
556};
557EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
558
559MODULE_LICENSE("GPL");
560MODULE_DESCRIPTION("Generic block chaining cipher type");
1/*
2 * Block chaining 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) 2006 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/skcipher.h>
18#include <crypto/scatterwalk.h>
19#include <linux/errno.h>
20#include <linux/hardirq.h>
21#include <linux/kernel.h>
22#include <linux/module.h>
23#include <linux/scatterlist.h>
24#include <linux/seq_file.h>
25#include <linux/slab.h>
26#include <linux/string.h>
27
28#include "internal.h"
29
30enum {
31 BLKCIPHER_WALK_PHYS = 1 << 0,
32 BLKCIPHER_WALK_SLOW = 1 << 1,
33 BLKCIPHER_WALK_COPY = 1 << 2,
34 BLKCIPHER_WALK_DIFF = 1 << 3,
35};
36
37static int blkcipher_walk_next(struct blkcipher_desc *desc,
38 struct blkcipher_walk *walk);
39static int blkcipher_walk_first(struct blkcipher_desc *desc,
40 struct blkcipher_walk *walk);
41
42static inline void blkcipher_map_src(struct blkcipher_walk *walk)
43{
44 walk->src.virt.addr = scatterwalk_map(&walk->in, 0);
45}
46
47static inline void blkcipher_map_dst(struct blkcipher_walk *walk)
48{
49 walk->dst.virt.addr = scatterwalk_map(&walk->out, 1);
50}
51
52static inline void blkcipher_unmap_src(struct blkcipher_walk *walk)
53{
54 scatterwalk_unmap(walk->src.virt.addr, 0);
55}
56
57static inline void blkcipher_unmap_dst(struct blkcipher_walk *walk)
58{
59 scatterwalk_unmap(walk->dst.virt.addr, 1);
60}
61
62/* Get a spot of the specified length that does not straddle a page.
63 * The caller needs to ensure that there is enough space for this operation.
64 */
65static inline u8 *blkcipher_get_spot(u8 *start, unsigned int len)
66{
67 u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
68 return max(start, end_page);
69}
70
71static inline unsigned int blkcipher_done_slow(struct crypto_blkcipher *tfm,
72 struct blkcipher_walk *walk,
73 unsigned int bsize)
74{
75 u8 *addr;
76 unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
77
78 addr = (u8 *)ALIGN((unsigned long)walk->buffer, alignmask + 1);
79 addr = blkcipher_get_spot(addr, bsize);
80 scatterwalk_copychunks(addr, &walk->out, bsize, 1);
81 return bsize;
82}
83
84static inline unsigned int blkcipher_done_fast(struct blkcipher_walk *walk,
85 unsigned int n)
86{
87 if (walk->flags & BLKCIPHER_WALK_COPY) {
88 blkcipher_map_dst(walk);
89 memcpy(walk->dst.virt.addr, walk->page, n);
90 blkcipher_unmap_dst(walk);
91 } else if (!(walk->flags & BLKCIPHER_WALK_PHYS)) {
92 if (walk->flags & BLKCIPHER_WALK_DIFF)
93 blkcipher_unmap_dst(walk);
94 blkcipher_unmap_src(walk);
95 }
96
97 scatterwalk_advance(&walk->in, n);
98 scatterwalk_advance(&walk->out, n);
99
100 return n;
101}
102
103int blkcipher_walk_done(struct blkcipher_desc *desc,
104 struct blkcipher_walk *walk, int err)
105{
106 struct crypto_blkcipher *tfm = desc->tfm;
107 unsigned int nbytes = 0;
108
109 if (likely(err >= 0)) {
110 unsigned int n = walk->nbytes - err;
111
112 if (likely(!(walk->flags & BLKCIPHER_WALK_SLOW)))
113 n = blkcipher_done_fast(walk, n);
114 else if (WARN_ON(err)) {
115 err = -EINVAL;
116 goto err;
117 } else
118 n = blkcipher_done_slow(tfm, walk, n);
119
120 nbytes = walk->total - n;
121 err = 0;
122 }
123
124 scatterwalk_done(&walk->in, 0, nbytes);
125 scatterwalk_done(&walk->out, 1, nbytes);
126
127err:
128 walk->total = nbytes;
129 walk->nbytes = nbytes;
130
131 if (nbytes) {
132 crypto_yield(desc->flags);
133 return blkcipher_walk_next(desc, walk);
134 }
135
136 if (walk->iv != desc->info)
137 memcpy(desc->info, walk->iv, crypto_blkcipher_ivsize(tfm));
138 if (walk->buffer != walk->page)
139 kfree(walk->buffer);
140 if (walk->page)
141 free_page((unsigned long)walk->page);
142
143 return err;
144}
145EXPORT_SYMBOL_GPL(blkcipher_walk_done);
146
147static inline int blkcipher_next_slow(struct blkcipher_desc *desc,
148 struct blkcipher_walk *walk,
149 unsigned int bsize,
150 unsigned int alignmask)
151{
152 unsigned int n;
153 unsigned aligned_bsize = ALIGN(bsize, alignmask + 1);
154
155 if (walk->buffer)
156 goto ok;
157
158 walk->buffer = walk->page;
159 if (walk->buffer)
160 goto ok;
161
162 n = aligned_bsize * 3 - (alignmask + 1) +
163 (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
164 walk->buffer = kmalloc(n, GFP_ATOMIC);
165 if (!walk->buffer)
166 return blkcipher_walk_done(desc, walk, -ENOMEM);
167
168ok:
169 walk->dst.virt.addr = (u8 *)ALIGN((unsigned long)walk->buffer,
170 alignmask + 1);
171 walk->dst.virt.addr = blkcipher_get_spot(walk->dst.virt.addr, bsize);
172 walk->src.virt.addr = blkcipher_get_spot(walk->dst.virt.addr +
173 aligned_bsize, bsize);
174
175 scatterwalk_copychunks(walk->src.virt.addr, &walk->in, bsize, 0);
176
177 walk->nbytes = bsize;
178 walk->flags |= BLKCIPHER_WALK_SLOW;
179
180 return 0;
181}
182
183static inline int blkcipher_next_copy(struct blkcipher_walk *walk)
184{
185 u8 *tmp = walk->page;
186
187 blkcipher_map_src(walk);
188 memcpy(tmp, walk->src.virt.addr, walk->nbytes);
189 blkcipher_unmap_src(walk);
190
191 walk->src.virt.addr = tmp;
192 walk->dst.virt.addr = tmp;
193
194 return 0;
195}
196
197static inline int blkcipher_next_fast(struct blkcipher_desc *desc,
198 struct blkcipher_walk *walk)
199{
200 unsigned long diff;
201
202 walk->src.phys.page = scatterwalk_page(&walk->in);
203 walk->src.phys.offset = offset_in_page(walk->in.offset);
204 walk->dst.phys.page = scatterwalk_page(&walk->out);
205 walk->dst.phys.offset = offset_in_page(walk->out.offset);
206
207 if (walk->flags & BLKCIPHER_WALK_PHYS)
208 return 0;
209
210 diff = walk->src.phys.offset - walk->dst.phys.offset;
211 diff |= walk->src.virt.page - walk->dst.virt.page;
212
213 blkcipher_map_src(walk);
214 walk->dst.virt.addr = walk->src.virt.addr;
215
216 if (diff) {
217 walk->flags |= BLKCIPHER_WALK_DIFF;
218 blkcipher_map_dst(walk);
219 }
220
221 return 0;
222}
223
224static int blkcipher_walk_next(struct blkcipher_desc *desc,
225 struct blkcipher_walk *walk)
226{
227 struct crypto_blkcipher *tfm = desc->tfm;
228 unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
229 unsigned int bsize;
230 unsigned int n;
231 int err;
232
233 n = walk->total;
234 if (unlikely(n < crypto_blkcipher_blocksize(tfm))) {
235 desc->flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN;
236 return blkcipher_walk_done(desc, walk, -EINVAL);
237 }
238
239 walk->flags &= ~(BLKCIPHER_WALK_SLOW | BLKCIPHER_WALK_COPY |
240 BLKCIPHER_WALK_DIFF);
241 if (!scatterwalk_aligned(&walk->in, alignmask) ||
242 !scatterwalk_aligned(&walk->out, alignmask)) {
243 walk->flags |= BLKCIPHER_WALK_COPY;
244 if (!walk->page) {
245 walk->page = (void *)__get_free_page(GFP_ATOMIC);
246 if (!walk->page)
247 n = 0;
248 }
249 }
250
251 bsize = min(walk->blocksize, n);
252 n = scatterwalk_clamp(&walk->in, n);
253 n = scatterwalk_clamp(&walk->out, n);
254
255 if (unlikely(n < bsize)) {
256 err = blkcipher_next_slow(desc, walk, bsize, alignmask);
257 goto set_phys_lowmem;
258 }
259
260 walk->nbytes = n;
261 if (walk->flags & BLKCIPHER_WALK_COPY) {
262 err = blkcipher_next_copy(walk);
263 goto set_phys_lowmem;
264 }
265
266 return blkcipher_next_fast(desc, walk);
267
268set_phys_lowmem:
269 if (walk->flags & BLKCIPHER_WALK_PHYS) {
270 walk->src.phys.page = virt_to_page(walk->src.virt.addr);
271 walk->dst.phys.page = virt_to_page(walk->dst.virt.addr);
272 walk->src.phys.offset &= PAGE_SIZE - 1;
273 walk->dst.phys.offset &= PAGE_SIZE - 1;
274 }
275 return err;
276}
277
278static inline int blkcipher_copy_iv(struct blkcipher_walk *walk,
279 struct crypto_blkcipher *tfm,
280 unsigned int alignmask)
281{
282 unsigned bs = walk->blocksize;
283 unsigned int ivsize = crypto_blkcipher_ivsize(tfm);
284 unsigned aligned_bs = ALIGN(bs, alignmask + 1);
285 unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) -
286 (alignmask + 1);
287 u8 *iv;
288
289 size += alignmask & ~(crypto_tfm_ctx_alignment() - 1);
290 walk->buffer = kmalloc(size, GFP_ATOMIC);
291 if (!walk->buffer)
292 return -ENOMEM;
293
294 iv = (u8 *)ALIGN((unsigned long)walk->buffer, alignmask + 1);
295 iv = blkcipher_get_spot(iv, bs) + aligned_bs;
296 iv = blkcipher_get_spot(iv, bs) + aligned_bs;
297 iv = blkcipher_get_spot(iv, ivsize);
298
299 walk->iv = memcpy(iv, walk->iv, ivsize);
300 return 0;
301}
302
303int blkcipher_walk_virt(struct blkcipher_desc *desc,
304 struct blkcipher_walk *walk)
305{
306 walk->flags &= ~BLKCIPHER_WALK_PHYS;
307 walk->blocksize = crypto_blkcipher_blocksize(desc->tfm);
308 return blkcipher_walk_first(desc, walk);
309}
310EXPORT_SYMBOL_GPL(blkcipher_walk_virt);
311
312int blkcipher_walk_phys(struct blkcipher_desc *desc,
313 struct blkcipher_walk *walk)
314{
315 walk->flags |= BLKCIPHER_WALK_PHYS;
316 walk->blocksize = crypto_blkcipher_blocksize(desc->tfm);
317 return blkcipher_walk_first(desc, walk);
318}
319EXPORT_SYMBOL_GPL(blkcipher_walk_phys);
320
321static int blkcipher_walk_first(struct blkcipher_desc *desc,
322 struct blkcipher_walk *walk)
323{
324 struct crypto_blkcipher *tfm = desc->tfm;
325 unsigned int alignmask = crypto_blkcipher_alignmask(tfm);
326
327 if (WARN_ON_ONCE(in_irq()))
328 return -EDEADLK;
329
330 walk->nbytes = walk->total;
331 if (unlikely(!walk->total))
332 return 0;
333
334 walk->buffer = NULL;
335 walk->iv = desc->info;
336 if (unlikely(((unsigned long)walk->iv & alignmask))) {
337 int err = blkcipher_copy_iv(walk, tfm, alignmask);
338 if (err)
339 return err;
340 }
341
342 scatterwalk_start(&walk->in, walk->in.sg);
343 scatterwalk_start(&walk->out, walk->out.sg);
344 walk->page = NULL;
345
346 return blkcipher_walk_next(desc, walk);
347}
348
349int blkcipher_walk_virt_block(struct blkcipher_desc *desc,
350 struct blkcipher_walk *walk,
351 unsigned int blocksize)
352{
353 walk->flags &= ~BLKCIPHER_WALK_PHYS;
354 walk->blocksize = blocksize;
355 return blkcipher_walk_first(desc, walk);
356}
357EXPORT_SYMBOL_GPL(blkcipher_walk_virt_block);
358
359static int setkey_unaligned(struct crypto_tfm *tfm, const u8 *key,
360 unsigned int keylen)
361{
362 struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
363 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
364 int ret;
365 u8 *buffer, *alignbuffer;
366 unsigned long absize;
367
368 absize = keylen + alignmask;
369 buffer = kmalloc(absize, GFP_ATOMIC);
370 if (!buffer)
371 return -ENOMEM;
372
373 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
374 memcpy(alignbuffer, key, keylen);
375 ret = cipher->setkey(tfm, alignbuffer, keylen);
376 memset(alignbuffer, 0, keylen);
377 kfree(buffer);
378 return ret;
379}
380
381static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
382{
383 struct blkcipher_alg *cipher = &tfm->__crt_alg->cra_blkcipher;
384 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
385
386 if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) {
387 tfm->crt_flags |= CRYPTO_TFM_RES_BAD_KEY_LEN;
388 return -EINVAL;
389 }
390
391 if ((unsigned long)key & alignmask)
392 return setkey_unaligned(tfm, key, keylen);
393
394 return cipher->setkey(tfm, key, keylen);
395}
396
397static int async_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
398 unsigned int keylen)
399{
400 return setkey(crypto_ablkcipher_tfm(tfm), key, keylen);
401}
402
403static int async_encrypt(struct ablkcipher_request *req)
404{
405 struct crypto_tfm *tfm = req->base.tfm;
406 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
407 struct blkcipher_desc desc = {
408 .tfm = __crypto_blkcipher_cast(tfm),
409 .info = req->info,
410 .flags = req->base.flags,
411 };
412
413
414 return alg->encrypt(&desc, req->dst, req->src, req->nbytes);
415}
416
417static int async_decrypt(struct ablkcipher_request *req)
418{
419 struct crypto_tfm *tfm = req->base.tfm;
420 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
421 struct blkcipher_desc desc = {
422 .tfm = __crypto_blkcipher_cast(tfm),
423 .info = req->info,
424 .flags = req->base.flags,
425 };
426
427 return alg->decrypt(&desc, req->dst, req->src, req->nbytes);
428}
429
430static unsigned int crypto_blkcipher_ctxsize(struct crypto_alg *alg, u32 type,
431 u32 mask)
432{
433 struct blkcipher_alg *cipher = &alg->cra_blkcipher;
434 unsigned int len = alg->cra_ctxsize;
435
436 if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK &&
437 cipher->ivsize) {
438 len = ALIGN(len, (unsigned long)alg->cra_alignmask + 1);
439 len += cipher->ivsize;
440 }
441
442 return len;
443}
444
445static int crypto_init_blkcipher_ops_async(struct crypto_tfm *tfm)
446{
447 struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher;
448 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
449
450 crt->setkey = async_setkey;
451 crt->encrypt = async_encrypt;
452 crt->decrypt = async_decrypt;
453 if (!alg->ivsize) {
454 crt->givencrypt = skcipher_null_givencrypt;
455 crt->givdecrypt = skcipher_null_givdecrypt;
456 }
457 crt->base = __crypto_ablkcipher_cast(tfm);
458 crt->ivsize = alg->ivsize;
459
460 return 0;
461}
462
463static int crypto_init_blkcipher_ops_sync(struct crypto_tfm *tfm)
464{
465 struct blkcipher_tfm *crt = &tfm->crt_blkcipher;
466 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
467 unsigned long align = crypto_tfm_alg_alignmask(tfm) + 1;
468 unsigned long addr;
469
470 crt->setkey = setkey;
471 crt->encrypt = alg->encrypt;
472 crt->decrypt = alg->decrypt;
473
474 addr = (unsigned long)crypto_tfm_ctx(tfm);
475 addr = ALIGN(addr, align);
476 addr += ALIGN(tfm->__crt_alg->cra_ctxsize, align);
477 crt->iv = (void *)addr;
478
479 return 0;
480}
481
482static int crypto_init_blkcipher_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
483{
484 struct blkcipher_alg *alg = &tfm->__crt_alg->cra_blkcipher;
485
486 if (alg->ivsize > PAGE_SIZE / 8)
487 return -EINVAL;
488
489 if ((mask & CRYPTO_ALG_TYPE_MASK) == CRYPTO_ALG_TYPE_MASK)
490 return crypto_init_blkcipher_ops_sync(tfm);
491 else
492 return crypto_init_blkcipher_ops_async(tfm);
493}
494
495static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
496 __attribute__ ((unused));
497static void crypto_blkcipher_show(struct seq_file *m, struct crypto_alg *alg)
498{
499 seq_printf(m, "type : blkcipher\n");
500 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
501 seq_printf(m, "min keysize : %u\n", alg->cra_blkcipher.min_keysize);
502 seq_printf(m, "max keysize : %u\n", alg->cra_blkcipher.max_keysize);
503 seq_printf(m, "ivsize : %u\n", alg->cra_blkcipher.ivsize);
504 seq_printf(m, "geniv : %s\n", alg->cra_blkcipher.geniv ?:
505 "<default>");
506}
507
508const struct crypto_type crypto_blkcipher_type = {
509 .ctxsize = crypto_blkcipher_ctxsize,
510 .init = crypto_init_blkcipher_ops,
511#ifdef CONFIG_PROC_FS
512 .show = crypto_blkcipher_show,
513#endif
514};
515EXPORT_SYMBOL_GPL(crypto_blkcipher_type);
516
517static int crypto_grab_nivcipher(struct crypto_skcipher_spawn *spawn,
518 const char *name, u32 type, u32 mask)
519{
520 struct crypto_alg *alg;
521 int err;
522
523 type = crypto_skcipher_type(type);
524 mask = crypto_skcipher_mask(mask)| CRYPTO_ALG_GENIV;
525
526 alg = crypto_alg_mod_lookup(name, type, mask);
527 if (IS_ERR(alg))
528 return PTR_ERR(alg);
529
530 err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask);
531 crypto_mod_put(alg);
532 return err;
533}
534
535struct crypto_instance *skcipher_geniv_alloc(struct crypto_template *tmpl,
536 struct rtattr **tb, u32 type,
537 u32 mask)
538{
539 struct {
540 int (*setkey)(struct crypto_ablkcipher *tfm, const u8 *key,
541 unsigned int keylen);
542 int (*encrypt)(struct ablkcipher_request *req);
543 int (*decrypt)(struct ablkcipher_request *req);
544
545 unsigned int min_keysize;
546 unsigned int max_keysize;
547 unsigned int ivsize;
548
549 const char *geniv;
550 } balg;
551 const char *name;
552 struct crypto_skcipher_spawn *spawn;
553 struct crypto_attr_type *algt;
554 struct crypto_instance *inst;
555 struct crypto_alg *alg;
556 int err;
557
558 algt = crypto_get_attr_type(tb);
559 err = PTR_ERR(algt);
560 if (IS_ERR(algt))
561 return ERR_PTR(err);
562
563 if ((algt->type ^ (CRYPTO_ALG_TYPE_GIVCIPHER | CRYPTO_ALG_GENIV)) &
564 algt->mask)
565 return ERR_PTR(-EINVAL);
566
567 name = crypto_attr_alg_name(tb[1]);
568 err = PTR_ERR(name);
569 if (IS_ERR(name))
570 return ERR_PTR(err);
571
572 inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
573 if (!inst)
574 return ERR_PTR(-ENOMEM);
575
576 spawn = crypto_instance_ctx(inst);
577
578 /* Ignore async algorithms if necessary. */
579 mask |= crypto_requires_sync(algt->type, algt->mask);
580
581 crypto_set_skcipher_spawn(spawn, inst);
582 err = crypto_grab_nivcipher(spawn, name, type, mask);
583 if (err)
584 goto err_free_inst;
585
586 alg = crypto_skcipher_spawn_alg(spawn);
587
588 if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) ==
589 CRYPTO_ALG_TYPE_BLKCIPHER) {
590 balg.ivsize = alg->cra_blkcipher.ivsize;
591 balg.min_keysize = alg->cra_blkcipher.min_keysize;
592 balg.max_keysize = alg->cra_blkcipher.max_keysize;
593
594 balg.setkey = async_setkey;
595 balg.encrypt = async_encrypt;
596 balg.decrypt = async_decrypt;
597
598 balg.geniv = alg->cra_blkcipher.geniv;
599 } else {
600 balg.ivsize = alg->cra_ablkcipher.ivsize;
601 balg.min_keysize = alg->cra_ablkcipher.min_keysize;
602 balg.max_keysize = alg->cra_ablkcipher.max_keysize;
603
604 balg.setkey = alg->cra_ablkcipher.setkey;
605 balg.encrypt = alg->cra_ablkcipher.encrypt;
606 balg.decrypt = alg->cra_ablkcipher.decrypt;
607
608 balg.geniv = alg->cra_ablkcipher.geniv;
609 }
610
611 err = -EINVAL;
612 if (!balg.ivsize)
613 goto err_drop_alg;
614
615 /*
616 * This is only true if we're constructing an algorithm with its
617 * default IV generator. For the default generator we elide the
618 * template name and double-check the IV generator.
619 */
620 if (algt->mask & CRYPTO_ALG_GENIV) {
621 if (!balg.geniv)
622 balg.geniv = crypto_default_geniv(alg);
623 err = -EAGAIN;
624 if (strcmp(tmpl->name, balg.geniv))
625 goto err_drop_alg;
626
627 memcpy(inst->alg.cra_name, alg->cra_name, CRYPTO_MAX_ALG_NAME);
628 memcpy(inst->alg.cra_driver_name, alg->cra_driver_name,
629 CRYPTO_MAX_ALG_NAME);
630 } else {
631 err = -ENAMETOOLONG;
632 if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME,
633 "%s(%s)", tmpl->name, alg->cra_name) >=
634 CRYPTO_MAX_ALG_NAME)
635 goto err_drop_alg;
636 if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME,
637 "%s(%s)", tmpl->name, alg->cra_driver_name) >=
638 CRYPTO_MAX_ALG_NAME)
639 goto err_drop_alg;
640 }
641
642 inst->alg.cra_flags = CRYPTO_ALG_TYPE_GIVCIPHER | CRYPTO_ALG_GENIV;
643 inst->alg.cra_flags |= alg->cra_flags & CRYPTO_ALG_ASYNC;
644 inst->alg.cra_priority = alg->cra_priority;
645 inst->alg.cra_blocksize = alg->cra_blocksize;
646 inst->alg.cra_alignmask = alg->cra_alignmask;
647 inst->alg.cra_type = &crypto_givcipher_type;
648
649 inst->alg.cra_ablkcipher.ivsize = balg.ivsize;
650 inst->alg.cra_ablkcipher.min_keysize = balg.min_keysize;
651 inst->alg.cra_ablkcipher.max_keysize = balg.max_keysize;
652 inst->alg.cra_ablkcipher.geniv = balg.geniv;
653
654 inst->alg.cra_ablkcipher.setkey = balg.setkey;
655 inst->alg.cra_ablkcipher.encrypt = balg.encrypt;
656 inst->alg.cra_ablkcipher.decrypt = balg.decrypt;
657
658out:
659 return inst;
660
661err_drop_alg:
662 crypto_drop_skcipher(spawn);
663err_free_inst:
664 kfree(inst);
665 inst = ERR_PTR(err);
666 goto out;
667}
668EXPORT_SYMBOL_GPL(skcipher_geniv_alloc);
669
670void skcipher_geniv_free(struct crypto_instance *inst)
671{
672 crypto_drop_skcipher(crypto_instance_ctx(inst));
673 kfree(inst);
674}
675EXPORT_SYMBOL_GPL(skcipher_geniv_free);
676
677int skcipher_geniv_init(struct crypto_tfm *tfm)
678{
679 struct crypto_instance *inst = (void *)tfm->__crt_alg;
680 struct crypto_ablkcipher *cipher;
681
682 cipher = crypto_spawn_skcipher(crypto_instance_ctx(inst));
683 if (IS_ERR(cipher))
684 return PTR_ERR(cipher);
685
686 tfm->crt_ablkcipher.base = cipher;
687 tfm->crt_ablkcipher.reqsize += crypto_ablkcipher_reqsize(cipher);
688
689 return 0;
690}
691EXPORT_SYMBOL_GPL(skcipher_geniv_init);
692
693void skcipher_geniv_exit(struct crypto_tfm *tfm)
694{
695 crypto_free_ablkcipher(tfm->crt_ablkcipher.base);
696}
697EXPORT_SYMBOL_GPL(skcipher_geniv_exit);
698
699MODULE_LICENSE("GPL");
700MODULE_DESCRIPTION("Generic block chaining cipher type");