Loading...
1/*
2 * Asynchronous Cryptographic Hash operations.
3 *
4 * This is the asynchronous version of hash.c with notification of
5 * completion via a callback.
6 *
7 * Copyright (c) 2008 Loc Ho <lho@amcc.com>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 */
15
16#include <crypto/internal/hash.h>
17#include <crypto/scatterwalk.h>
18#include <linux/bug.h>
19#include <linux/err.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/sched.h>
23#include <linux/slab.h>
24#include <linux/seq_file.h>
25#include <linux/cryptouser.h>
26#include <net/netlink.h>
27
28#include "internal.h"
29
30struct ahash_request_priv {
31 crypto_completion_t complete;
32 void *data;
33 u8 *result;
34 void *ubuf[] CRYPTO_MINALIGN_ATTR;
35};
36
37static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
38{
39 return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
40 halg);
41}
42
43static int hash_walk_next(struct crypto_hash_walk *walk)
44{
45 unsigned int alignmask = walk->alignmask;
46 unsigned int offset = walk->offset;
47 unsigned int nbytes = min(walk->entrylen,
48 ((unsigned int)(PAGE_SIZE)) - offset);
49
50 if (walk->flags & CRYPTO_ALG_ASYNC)
51 walk->data = kmap(walk->pg);
52 else
53 walk->data = kmap_atomic(walk->pg);
54 walk->data += offset;
55
56 if (offset & alignmask) {
57 unsigned int unaligned = alignmask + 1 - (offset & alignmask);
58
59 if (nbytes > unaligned)
60 nbytes = unaligned;
61 }
62
63 walk->entrylen -= nbytes;
64 return nbytes;
65}
66
67static int hash_walk_new_entry(struct crypto_hash_walk *walk)
68{
69 struct scatterlist *sg;
70
71 sg = walk->sg;
72 walk->offset = sg->offset;
73 walk->pg = sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
74 walk->offset = offset_in_page(walk->offset);
75 walk->entrylen = sg->length;
76
77 if (walk->entrylen > walk->total)
78 walk->entrylen = walk->total;
79 walk->total -= walk->entrylen;
80
81 return hash_walk_next(walk);
82}
83
84int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
85{
86 unsigned int alignmask = walk->alignmask;
87 unsigned int nbytes = walk->entrylen;
88
89 walk->data -= walk->offset;
90
91 if (nbytes && walk->offset & alignmask && !err) {
92 walk->offset = ALIGN(walk->offset, alignmask + 1);
93 walk->data += walk->offset;
94
95 nbytes = min(nbytes,
96 ((unsigned int)(PAGE_SIZE)) - walk->offset);
97 walk->entrylen -= nbytes;
98
99 return nbytes;
100 }
101
102 if (walk->flags & CRYPTO_ALG_ASYNC)
103 kunmap(walk->pg);
104 else {
105 kunmap_atomic(walk->data);
106 /*
107 * The may sleep test only makes sense for sync users.
108 * Async users don't need to sleep here anyway.
109 */
110 crypto_yield(walk->flags);
111 }
112
113 if (err)
114 return err;
115
116 if (nbytes) {
117 walk->offset = 0;
118 walk->pg++;
119 return hash_walk_next(walk);
120 }
121
122 if (!walk->total)
123 return 0;
124
125 walk->sg = sg_next(walk->sg);
126
127 return hash_walk_new_entry(walk);
128}
129EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
130
131int crypto_hash_walk_first(struct ahash_request *req,
132 struct crypto_hash_walk *walk)
133{
134 walk->total = req->nbytes;
135
136 if (!walk->total) {
137 walk->entrylen = 0;
138 return 0;
139 }
140
141 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
142 walk->sg = req->src;
143 walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
144
145 return hash_walk_new_entry(walk);
146}
147EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
148
149int crypto_ahash_walk_first(struct ahash_request *req,
150 struct crypto_hash_walk *walk)
151{
152 walk->total = req->nbytes;
153
154 if (!walk->total) {
155 walk->entrylen = 0;
156 return 0;
157 }
158
159 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
160 walk->sg = req->src;
161 walk->flags = req->base.flags & CRYPTO_TFM_REQ_MASK;
162 walk->flags |= CRYPTO_ALG_ASYNC;
163
164 BUILD_BUG_ON(CRYPTO_TFM_REQ_MASK & CRYPTO_ALG_ASYNC);
165
166 return hash_walk_new_entry(walk);
167}
168EXPORT_SYMBOL_GPL(crypto_ahash_walk_first);
169
170static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
171 unsigned int keylen)
172{
173 unsigned long alignmask = crypto_ahash_alignmask(tfm);
174 int ret;
175 u8 *buffer, *alignbuffer;
176 unsigned long absize;
177
178 absize = keylen + alignmask;
179 buffer = kmalloc(absize, GFP_KERNEL);
180 if (!buffer)
181 return -ENOMEM;
182
183 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
184 memcpy(alignbuffer, key, keylen);
185 ret = tfm->setkey(tfm, alignbuffer, keylen);
186 kzfree(buffer);
187 return ret;
188}
189
190int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
191 unsigned int keylen)
192{
193 unsigned long alignmask = crypto_ahash_alignmask(tfm);
194
195 if ((unsigned long)key & alignmask)
196 return ahash_setkey_unaligned(tfm, key, keylen);
197
198 return tfm->setkey(tfm, key, keylen);
199}
200EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
201
202static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
203 unsigned int keylen)
204{
205 return -ENOSYS;
206}
207
208static inline unsigned int ahash_align_buffer_size(unsigned len,
209 unsigned long mask)
210{
211 return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
212}
213
214static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
215{
216 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
217 unsigned long alignmask = crypto_ahash_alignmask(tfm);
218 unsigned int ds = crypto_ahash_digestsize(tfm);
219 struct ahash_request_priv *priv;
220
221 priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
222 (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
223 GFP_KERNEL : GFP_ATOMIC);
224 if (!priv)
225 return -ENOMEM;
226
227 /*
228 * WARNING: Voodoo programming below!
229 *
230 * The code below is obscure and hard to understand, thus explanation
231 * is necessary. See include/crypto/hash.h and include/linux/crypto.h
232 * to understand the layout of structures used here!
233 *
234 * The code here will replace portions of the ORIGINAL request with
235 * pointers to new code and buffers so the hashing operation can store
236 * the result in aligned buffer. We will call the modified request
237 * an ADJUSTED request.
238 *
239 * The newly mangled request will look as such:
240 *
241 * req {
242 * .result = ADJUSTED[new aligned buffer]
243 * .base.complete = ADJUSTED[pointer to completion function]
244 * .base.data = ADJUSTED[*req (pointer to self)]
245 * .priv = ADJUSTED[new priv] {
246 * .result = ORIGINAL(result)
247 * .complete = ORIGINAL(base.complete)
248 * .data = ORIGINAL(base.data)
249 * }
250 */
251
252 priv->result = req->result;
253 priv->complete = req->base.complete;
254 priv->data = req->base.data;
255 /*
256 * WARNING: We do not backup req->priv here! The req->priv
257 * is for internal use of the Crypto API and the
258 * user must _NOT_ _EVER_ depend on it's content!
259 */
260
261 req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
262 req->base.complete = cplt;
263 req->base.data = req;
264 req->priv = priv;
265
266 return 0;
267}
268
269static void ahash_restore_req(struct ahash_request *req)
270{
271 struct ahash_request_priv *priv = req->priv;
272
273 /* Restore the original crypto request. */
274 req->result = priv->result;
275 req->base.complete = priv->complete;
276 req->base.data = priv->data;
277 req->priv = NULL;
278
279 /* Free the req->priv.priv from the ADJUSTED request. */
280 kzfree(priv);
281}
282
283static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
284{
285 struct ahash_request_priv *priv = req->priv;
286
287 if (err == -EINPROGRESS)
288 return;
289
290 if (!err)
291 memcpy(priv->result, req->result,
292 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
293
294 ahash_restore_req(req);
295}
296
297static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
298{
299 struct ahash_request *areq = req->data;
300
301 /*
302 * Restore the original request, see ahash_op_unaligned() for what
303 * goes where.
304 *
305 * The "struct ahash_request *req" here is in fact the "req.base"
306 * from the ADJUSTED request from ahash_op_unaligned(), thus as it
307 * is a pointer to self, it is also the ADJUSTED "req" .
308 */
309
310 /* First copy req->result into req->priv.result */
311 ahash_op_unaligned_finish(areq, err);
312
313 /* Complete the ORIGINAL request. */
314 areq->base.complete(&areq->base, err);
315}
316
317static int ahash_op_unaligned(struct ahash_request *req,
318 int (*op)(struct ahash_request *))
319{
320 int err;
321
322 err = ahash_save_req(req, ahash_op_unaligned_done);
323 if (err)
324 return err;
325
326 err = op(req);
327 ahash_op_unaligned_finish(req, err);
328
329 return err;
330}
331
332static int crypto_ahash_op(struct ahash_request *req,
333 int (*op)(struct ahash_request *))
334{
335 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
336 unsigned long alignmask = crypto_ahash_alignmask(tfm);
337
338 if ((unsigned long)req->result & alignmask)
339 return ahash_op_unaligned(req, op);
340
341 return op(req);
342}
343
344int crypto_ahash_final(struct ahash_request *req)
345{
346 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
347}
348EXPORT_SYMBOL_GPL(crypto_ahash_final);
349
350int crypto_ahash_finup(struct ahash_request *req)
351{
352 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
353}
354EXPORT_SYMBOL_GPL(crypto_ahash_finup);
355
356int crypto_ahash_digest(struct ahash_request *req)
357{
358 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
359}
360EXPORT_SYMBOL_GPL(crypto_ahash_digest);
361
362static void ahash_def_finup_finish2(struct ahash_request *req, int err)
363{
364 struct ahash_request_priv *priv = req->priv;
365
366 if (err == -EINPROGRESS)
367 return;
368
369 if (!err)
370 memcpy(priv->result, req->result,
371 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
372
373 ahash_restore_req(req);
374}
375
376static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
377{
378 struct ahash_request *areq = req->data;
379
380 ahash_def_finup_finish2(areq, err);
381
382 areq->base.complete(&areq->base, err);
383}
384
385static int ahash_def_finup_finish1(struct ahash_request *req, int err)
386{
387 if (err)
388 goto out;
389
390 req->base.complete = ahash_def_finup_done2;
391 req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
392 err = crypto_ahash_reqtfm(req)->final(req);
393
394out:
395 ahash_def_finup_finish2(req, err);
396 return err;
397}
398
399static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
400{
401 struct ahash_request *areq = req->data;
402
403 err = ahash_def_finup_finish1(areq, err);
404
405 areq->base.complete(&areq->base, err);
406}
407
408static int ahash_def_finup(struct ahash_request *req)
409{
410 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
411 int err;
412
413 err = ahash_save_req(req, ahash_def_finup_done1);
414 if (err)
415 return err;
416
417 err = tfm->update(req);
418 return ahash_def_finup_finish1(req, err);
419}
420
421static int ahash_no_export(struct ahash_request *req, void *out)
422{
423 return -ENOSYS;
424}
425
426static int ahash_no_import(struct ahash_request *req, const void *in)
427{
428 return -ENOSYS;
429}
430
431static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
432{
433 struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
434 struct ahash_alg *alg = crypto_ahash_alg(hash);
435
436 hash->setkey = ahash_nosetkey;
437 hash->has_setkey = false;
438 hash->export = ahash_no_export;
439 hash->import = ahash_no_import;
440
441 if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
442 return crypto_init_shash_ops_async(tfm);
443
444 hash->init = alg->init;
445 hash->update = alg->update;
446 hash->final = alg->final;
447 hash->finup = alg->finup ?: ahash_def_finup;
448 hash->digest = alg->digest;
449
450 if (alg->setkey) {
451 hash->setkey = alg->setkey;
452 hash->has_setkey = true;
453 }
454 if (alg->export)
455 hash->export = alg->export;
456 if (alg->import)
457 hash->import = alg->import;
458
459 return 0;
460}
461
462static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
463{
464 if (alg->cra_type == &crypto_ahash_type)
465 return alg->cra_ctxsize;
466
467 return sizeof(struct crypto_shash *);
468}
469
470#ifdef CONFIG_NET
471static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
472{
473 struct crypto_report_hash rhash;
474
475 strncpy(rhash.type, "ahash", sizeof(rhash.type));
476
477 rhash.blocksize = alg->cra_blocksize;
478 rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
479
480 if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
481 sizeof(struct crypto_report_hash), &rhash))
482 goto nla_put_failure;
483 return 0;
484
485nla_put_failure:
486 return -EMSGSIZE;
487}
488#else
489static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
490{
491 return -ENOSYS;
492}
493#endif
494
495static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
496 __attribute__ ((unused));
497static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
498{
499 seq_printf(m, "type : ahash\n");
500 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
501 "yes" : "no");
502 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
503 seq_printf(m, "digestsize : %u\n",
504 __crypto_hash_alg_common(alg)->digestsize);
505}
506
507const struct crypto_type crypto_ahash_type = {
508 .extsize = crypto_ahash_extsize,
509 .init_tfm = crypto_ahash_init_tfm,
510#ifdef CONFIG_PROC_FS
511 .show = crypto_ahash_show,
512#endif
513 .report = crypto_ahash_report,
514 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
515 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
516 .type = CRYPTO_ALG_TYPE_AHASH,
517 .tfmsize = offsetof(struct crypto_ahash, base),
518};
519EXPORT_SYMBOL_GPL(crypto_ahash_type);
520
521struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
522 u32 mask)
523{
524 return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
525}
526EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
527
528int crypto_has_ahash(const char *alg_name, u32 type, u32 mask)
529{
530 return crypto_type_has_alg(alg_name, &crypto_ahash_type, type, mask);
531}
532EXPORT_SYMBOL_GPL(crypto_has_ahash);
533
534static int ahash_prepare_alg(struct ahash_alg *alg)
535{
536 struct crypto_alg *base = &alg->halg.base;
537
538 if (alg->halg.digestsize > PAGE_SIZE / 8 ||
539 alg->halg.statesize > PAGE_SIZE / 8 ||
540 alg->halg.statesize == 0)
541 return -EINVAL;
542
543 base->cra_type = &crypto_ahash_type;
544 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
545 base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
546
547 return 0;
548}
549
550int crypto_register_ahash(struct ahash_alg *alg)
551{
552 struct crypto_alg *base = &alg->halg.base;
553 int err;
554
555 err = ahash_prepare_alg(alg);
556 if (err)
557 return err;
558
559 return crypto_register_alg(base);
560}
561EXPORT_SYMBOL_GPL(crypto_register_ahash);
562
563int crypto_unregister_ahash(struct ahash_alg *alg)
564{
565 return crypto_unregister_alg(&alg->halg.base);
566}
567EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
568
569int ahash_register_instance(struct crypto_template *tmpl,
570 struct ahash_instance *inst)
571{
572 int err;
573
574 err = ahash_prepare_alg(&inst->alg);
575 if (err)
576 return err;
577
578 return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
579}
580EXPORT_SYMBOL_GPL(ahash_register_instance);
581
582void ahash_free_instance(struct crypto_instance *inst)
583{
584 crypto_drop_spawn(crypto_instance_ctx(inst));
585 kfree(ahash_instance(inst));
586}
587EXPORT_SYMBOL_GPL(ahash_free_instance);
588
589int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
590 struct hash_alg_common *alg,
591 struct crypto_instance *inst)
592{
593 return crypto_init_spawn2(&spawn->base, &alg->base, inst,
594 &crypto_ahash_type);
595}
596EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
597
598struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
599{
600 struct crypto_alg *alg;
601
602 alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
603 return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
604}
605EXPORT_SYMBOL_GPL(ahash_attr_alg);
606
607MODULE_LICENSE("GPL");
608MODULE_DESCRIPTION("Asynchronous cryptographic hash type");
1/*
2 * Asynchronous Cryptographic Hash operations.
3 *
4 * This is the asynchronous version of hash.c with notification of
5 * completion via a callback.
6 *
7 * Copyright (c) 2008 Loc Ho <lho@amcc.com>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 */
15
16#include <crypto/internal/hash.h>
17#include <crypto/scatterwalk.h>
18#include <linux/err.h>
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/sched.h>
22#include <linux/slab.h>
23#include <linux/seq_file.h>
24#include <linux/cryptouser.h>
25#include <net/netlink.h>
26
27#include "internal.h"
28
29struct ahash_request_priv {
30 crypto_completion_t complete;
31 void *data;
32 u8 *result;
33 void *ubuf[] CRYPTO_MINALIGN_ATTR;
34};
35
36static inline struct ahash_alg *crypto_ahash_alg(struct crypto_ahash *hash)
37{
38 return container_of(crypto_hash_alg_common(hash), struct ahash_alg,
39 halg);
40}
41
42static int hash_walk_next(struct crypto_hash_walk *walk)
43{
44 unsigned int alignmask = walk->alignmask;
45 unsigned int offset = walk->offset;
46 unsigned int nbytes = min(walk->entrylen,
47 ((unsigned int)(PAGE_SIZE)) - offset);
48
49 walk->data = kmap_atomic(walk->pg);
50 walk->data += offset;
51
52 if (offset & alignmask) {
53 unsigned int unaligned = alignmask + 1 - (offset & alignmask);
54 if (nbytes > unaligned)
55 nbytes = unaligned;
56 }
57
58 walk->entrylen -= nbytes;
59 return nbytes;
60}
61
62static int hash_walk_new_entry(struct crypto_hash_walk *walk)
63{
64 struct scatterlist *sg;
65
66 sg = walk->sg;
67 walk->pg = sg_page(sg);
68 walk->offset = sg->offset;
69 walk->entrylen = sg->length;
70
71 if (walk->entrylen > walk->total)
72 walk->entrylen = walk->total;
73 walk->total -= walk->entrylen;
74
75 return hash_walk_next(walk);
76}
77
78int crypto_hash_walk_done(struct crypto_hash_walk *walk, int err)
79{
80 unsigned int alignmask = walk->alignmask;
81 unsigned int nbytes = walk->entrylen;
82
83 walk->data -= walk->offset;
84
85 if (nbytes && walk->offset & alignmask && !err) {
86 walk->offset = ALIGN(walk->offset, alignmask + 1);
87 walk->data += walk->offset;
88
89 nbytes = min(nbytes,
90 ((unsigned int)(PAGE_SIZE)) - walk->offset);
91 walk->entrylen -= nbytes;
92
93 return nbytes;
94 }
95
96 kunmap_atomic(walk->data);
97 crypto_yield(walk->flags);
98
99 if (err)
100 return err;
101
102 if (nbytes) {
103 walk->offset = 0;
104 walk->pg++;
105 return hash_walk_next(walk);
106 }
107
108 if (!walk->total)
109 return 0;
110
111 walk->sg = scatterwalk_sg_next(walk->sg);
112
113 return hash_walk_new_entry(walk);
114}
115EXPORT_SYMBOL_GPL(crypto_hash_walk_done);
116
117int crypto_hash_walk_first(struct ahash_request *req,
118 struct crypto_hash_walk *walk)
119{
120 walk->total = req->nbytes;
121
122 if (!walk->total)
123 return 0;
124
125 walk->alignmask = crypto_ahash_alignmask(crypto_ahash_reqtfm(req));
126 walk->sg = req->src;
127 walk->flags = req->base.flags;
128
129 return hash_walk_new_entry(walk);
130}
131EXPORT_SYMBOL_GPL(crypto_hash_walk_first);
132
133int crypto_hash_walk_first_compat(struct hash_desc *hdesc,
134 struct crypto_hash_walk *walk,
135 struct scatterlist *sg, unsigned int len)
136{
137 walk->total = len;
138
139 if (!walk->total)
140 return 0;
141
142 walk->alignmask = crypto_hash_alignmask(hdesc->tfm);
143 walk->sg = sg;
144 walk->flags = hdesc->flags;
145
146 return hash_walk_new_entry(walk);
147}
148
149static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
150 unsigned int keylen)
151{
152 unsigned long alignmask = crypto_ahash_alignmask(tfm);
153 int ret;
154 u8 *buffer, *alignbuffer;
155 unsigned long absize;
156
157 absize = keylen + alignmask;
158 buffer = kmalloc(absize, GFP_KERNEL);
159 if (!buffer)
160 return -ENOMEM;
161
162 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
163 memcpy(alignbuffer, key, keylen);
164 ret = tfm->setkey(tfm, alignbuffer, keylen);
165 kzfree(buffer);
166 return ret;
167}
168
169int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
170 unsigned int keylen)
171{
172 unsigned long alignmask = crypto_ahash_alignmask(tfm);
173
174 if ((unsigned long)key & alignmask)
175 return ahash_setkey_unaligned(tfm, key, keylen);
176
177 return tfm->setkey(tfm, key, keylen);
178}
179EXPORT_SYMBOL_GPL(crypto_ahash_setkey);
180
181static int ahash_nosetkey(struct crypto_ahash *tfm, const u8 *key,
182 unsigned int keylen)
183{
184 return -ENOSYS;
185}
186
187static inline unsigned int ahash_align_buffer_size(unsigned len,
188 unsigned long mask)
189{
190 return len + (mask & ~(crypto_tfm_ctx_alignment() - 1));
191}
192
193static int ahash_save_req(struct ahash_request *req, crypto_completion_t cplt)
194{
195 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
196 unsigned long alignmask = crypto_ahash_alignmask(tfm);
197 unsigned int ds = crypto_ahash_digestsize(tfm);
198 struct ahash_request_priv *priv;
199
200 priv = kmalloc(sizeof(*priv) + ahash_align_buffer_size(ds, alignmask),
201 (req->base.flags & CRYPTO_TFM_REQ_MAY_SLEEP) ?
202 GFP_KERNEL : GFP_ATOMIC);
203 if (!priv)
204 return -ENOMEM;
205
206 /*
207 * WARNING: Voodoo programming below!
208 *
209 * The code below is obscure and hard to understand, thus explanation
210 * is necessary. See include/crypto/hash.h and include/linux/crypto.h
211 * to understand the layout of structures used here!
212 *
213 * The code here will replace portions of the ORIGINAL request with
214 * pointers to new code and buffers so the hashing operation can store
215 * the result in aligned buffer. We will call the modified request
216 * an ADJUSTED request.
217 *
218 * The newly mangled request will look as such:
219 *
220 * req {
221 * .result = ADJUSTED[new aligned buffer]
222 * .base.complete = ADJUSTED[pointer to completion function]
223 * .base.data = ADJUSTED[*req (pointer to self)]
224 * .priv = ADJUSTED[new priv] {
225 * .result = ORIGINAL(result)
226 * .complete = ORIGINAL(base.complete)
227 * .data = ORIGINAL(base.data)
228 * }
229 */
230
231 priv->result = req->result;
232 priv->complete = req->base.complete;
233 priv->data = req->base.data;
234 /*
235 * WARNING: We do not backup req->priv here! The req->priv
236 * is for internal use of the Crypto API and the
237 * user must _NOT_ _EVER_ depend on it's content!
238 */
239
240 req->result = PTR_ALIGN((u8 *)priv->ubuf, alignmask + 1);
241 req->base.complete = cplt;
242 req->base.data = req;
243 req->priv = priv;
244
245 return 0;
246}
247
248static void ahash_restore_req(struct ahash_request *req)
249{
250 struct ahash_request_priv *priv = req->priv;
251
252 /* Restore the original crypto request. */
253 req->result = priv->result;
254 req->base.complete = priv->complete;
255 req->base.data = priv->data;
256 req->priv = NULL;
257
258 /* Free the req->priv.priv from the ADJUSTED request. */
259 kzfree(priv);
260}
261
262static void ahash_op_unaligned_finish(struct ahash_request *req, int err)
263{
264 struct ahash_request_priv *priv = req->priv;
265
266 if (err == -EINPROGRESS)
267 return;
268
269 if (!err)
270 memcpy(priv->result, req->result,
271 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
272
273 ahash_restore_req(req);
274}
275
276static void ahash_op_unaligned_done(struct crypto_async_request *req, int err)
277{
278 struct ahash_request *areq = req->data;
279
280 /*
281 * Restore the original request, see ahash_op_unaligned() for what
282 * goes where.
283 *
284 * The "struct ahash_request *req" here is in fact the "req.base"
285 * from the ADJUSTED request from ahash_op_unaligned(), thus as it
286 * is a pointer to self, it is also the ADJUSTED "req" .
287 */
288
289 /* First copy req->result into req->priv.result */
290 ahash_op_unaligned_finish(areq, err);
291
292 /* Complete the ORIGINAL request. */
293 areq->base.complete(&areq->base, err);
294}
295
296static int ahash_op_unaligned(struct ahash_request *req,
297 int (*op)(struct ahash_request *))
298{
299 int err;
300
301 err = ahash_save_req(req, ahash_op_unaligned_done);
302 if (err)
303 return err;
304
305 err = op(req);
306 ahash_op_unaligned_finish(req, err);
307
308 return err;
309}
310
311static int crypto_ahash_op(struct ahash_request *req,
312 int (*op)(struct ahash_request *))
313{
314 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
315 unsigned long alignmask = crypto_ahash_alignmask(tfm);
316
317 if ((unsigned long)req->result & alignmask)
318 return ahash_op_unaligned(req, op);
319
320 return op(req);
321}
322
323int crypto_ahash_final(struct ahash_request *req)
324{
325 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->final);
326}
327EXPORT_SYMBOL_GPL(crypto_ahash_final);
328
329int crypto_ahash_finup(struct ahash_request *req)
330{
331 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->finup);
332}
333EXPORT_SYMBOL_GPL(crypto_ahash_finup);
334
335int crypto_ahash_digest(struct ahash_request *req)
336{
337 return crypto_ahash_op(req, crypto_ahash_reqtfm(req)->digest);
338}
339EXPORT_SYMBOL_GPL(crypto_ahash_digest);
340
341static void ahash_def_finup_finish2(struct ahash_request *req, int err)
342{
343 struct ahash_request_priv *priv = req->priv;
344
345 if (err == -EINPROGRESS)
346 return;
347
348 if (!err)
349 memcpy(priv->result, req->result,
350 crypto_ahash_digestsize(crypto_ahash_reqtfm(req)));
351
352 ahash_restore_req(req);
353}
354
355static void ahash_def_finup_done2(struct crypto_async_request *req, int err)
356{
357 struct ahash_request *areq = req->data;
358
359 ahash_def_finup_finish2(areq, err);
360
361 areq->base.complete(&areq->base, err);
362}
363
364static int ahash_def_finup_finish1(struct ahash_request *req, int err)
365{
366 if (err)
367 goto out;
368
369 req->base.complete = ahash_def_finup_done2;
370 req->base.flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP;
371 err = crypto_ahash_reqtfm(req)->final(req);
372
373out:
374 ahash_def_finup_finish2(req, err);
375 return err;
376}
377
378static void ahash_def_finup_done1(struct crypto_async_request *req, int err)
379{
380 struct ahash_request *areq = req->data;
381
382 err = ahash_def_finup_finish1(areq, err);
383
384 areq->base.complete(&areq->base, err);
385}
386
387static int ahash_def_finup(struct ahash_request *req)
388{
389 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
390 int err;
391
392 err = ahash_save_req(req, ahash_def_finup_done1);
393 if (err)
394 return err;
395
396 err = tfm->update(req);
397 return ahash_def_finup_finish1(req, err);
398}
399
400static int ahash_no_export(struct ahash_request *req, void *out)
401{
402 return -ENOSYS;
403}
404
405static int ahash_no_import(struct ahash_request *req, const void *in)
406{
407 return -ENOSYS;
408}
409
410static int crypto_ahash_init_tfm(struct crypto_tfm *tfm)
411{
412 struct crypto_ahash *hash = __crypto_ahash_cast(tfm);
413 struct ahash_alg *alg = crypto_ahash_alg(hash);
414
415 hash->setkey = ahash_nosetkey;
416 hash->export = ahash_no_export;
417 hash->import = ahash_no_import;
418
419 if (tfm->__crt_alg->cra_type != &crypto_ahash_type)
420 return crypto_init_shash_ops_async(tfm);
421
422 hash->init = alg->init;
423 hash->update = alg->update;
424 hash->final = alg->final;
425 hash->finup = alg->finup ?: ahash_def_finup;
426 hash->digest = alg->digest;
427
428 if (alg->setkey)
429 hash->setkey = alg->setkey;
430 if (alg->export)
431 hash->export = alg->export;
432 if (alg->import)
433 hash->import = alg->import;
434
435 return 0;
436}
437
438static unsigned int crypto_ahash_extsize(struct crypto_alg *alg)
439{
440 if (alg->cra_type == &crypto_ahash_type)
441 return alg->cra_ctxsize;
442
443 return sizeof(struct crypto_shash *);
444}
445
446#ifdef CONFIG_NET
447static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
448{
449 struct crypto_report_hash rhash;
450
451 strncpy(rhash.type, "ahash", sizeof(rhash.type));
452
453 rhash.blocksize = alg->cra_blocksize;
454 rhash.digestsize = __crypto_hash_alg_common(alg)->digestsize;
455
456 if (nla_put(skb, CRYPTOCFGA_REPORT_HASH,
457 sizeof(struct crypto_report_hash), &rhash))
458 goto nla_put_failure;
459 return 0;
460
461nla_put_failure:
462 return -EMSGSIZE;
463}
464#else
465static int crypto_ahash_report(struct sk_buff *skb, struct crypto_alg *alg)
466{
467 return -ENOSYS;
468}
469#endif
470
471static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
472 __attribute__ ((unused));
473static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
474{
475 seq_printf(m, "type : ahash\n");
476 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
477 "yes" : "no");
478 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
479 seq_printf(m, "digestsize : %u\n",
480 __crypto_hash_alg_common(alg)->digestsize);
481}
482
483const struct crypto_type crypto_ahash_type = {
484 .extsize = crypto_ahash_extsize,
485 .init_tfm = crypto_ahash_init_tfm,
486#ifdef CONFIG_PROC_FS
487 .show = crypto_ahash_show,
488#endif
489 .report = crypto_ahash_report,
490 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
491 .maskset = CRYPTO_ALG_TYPE_AHASH_MASK,
492 .type = CRYPTO_ALG_TYPE_AHASH,
493 .tfmsize = offsetof(struct crypto_ahash, base),
494};
495EXPORT_SYMBOL_GPL(crypto_ahash_type);
496
497struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
498 u32 mask)
499{
500 return crypto_alloc_tfm(alg_name, &crypto_ahash_type, type, mask);
501}
502EXPORT_SYMBOL_GPL(crypto_alloc_ahash);
503
504static int ahash_prepare_alg(struct ahash_alg *alg)
505{
506 struct crypto_alg *base = &alg->halg.base;
507
508 if (alg->halg.digestsize > PAGE_SIZE / 8 ||
509 alg->halg.statesize > PAGE_SIZE / 8)
510 return -EINVAL;
511
512 base->cra_type = &crypto_ahash_type;
513 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
514 base->cra_flags |= CRYPTO_ALG_TYPE_AHASH;
515
516 return 0;
517}
518
519int crypto_register_ahash(struct ahash_alg *alg)
520{
521 struct crypto_alg *base = &alg->halg.base;
522 int err;
523
524 err = ahash_prepare_alg(alg);
525 if (err)
526 return err;
527
528 return crypto_register_alg(base);
529}
530EXPORT_SYMBOL_GPL(crypto_register_ahash);
531
532int crypto_unregister_ahash(struct ahash_alg *alg)
533{
534 return crypto_unregister_alg(&alg->halg.base);
535}
536EXPORT_SYMBOL_GPL(crypto_unregister_ahash);
537
538int ahash_register_instance(struct crypto_template *tmpl,
539 struct ahash_instance *inst)
540{
541 int err;
542
543 err = ahash_prepare_alg(&inst->alg);
544 if (err)
545 return err;
546
547 return crypto_register_instance(tmpl, ahash_crypto_instance(inst));
548}
549EXPORT_SYMBOL_GPL(ahash_register_instance);
550
551void ahash_free_instance(struct crypto_instance *inst)
552{
553 crypto_drop_spawn(crypto_instance_ctx(inst));
554 kfree(ahash_instance(inst));
555}
556EXPORT_SYMBOL_GPL(ahash_free_instance);
557
558int crypto_init_ahash_spawn(struct crypto_ahash_spawn *spawn,
559 struct hash_alg_common *alg,
560 struct crypto_instance *inst)
561{
562 return crypto_init_spawn2(&spawn->base, &alg->base, inst,
563 &crypto_ahash_type);
564}
565EXPORT_SYMBOL_GPL(crypto_init_ahash_spawn);
566
567struct hash_alg_common *ahash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
568{
569 struct crypto_alg *alg;
570
571 alg = crypto_attr_alg2(rta, &crypto_ahash_type, type, mask);
572 return IS_ERR(alg) ? ERR_CAST(alg) : __crypto_hash_alg_common(alg);
573}
574EXPORT_SYMBOL_GPL(ahash_attr_alg);
575
576MODULE_LICENSE("GPL");
577MODULE_DESCRIPTION("Asynchronous cryptographic hash type");