USB: emi62: fix crash when trying to load EMI 6|2 firmware
[linux-2.6.git] / crypto / shash.c
1 /*
2  * Synchronous Cryptographic Hash operations.
3  *
4  * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms of the GNU General Public License as published by the Free
8  * Software Foundation; either version 2 of the License, or (at your option)
9  * any later version.
10  *
11  */
12
13 #include <crypto/scatterwalk.h>
14 #include <crypto/internal/hash.h>
15 #include <linux/err.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/slab.h>
19 #include <linux/seq_file.h>
20
21 #include "internal.h"
22
23 static const struct crypto_type crypto_shash_type;
24
25 static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
26                            unsigned int keylen)
27 {
28         return -ENOSYS;
29 }
30
31 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
32                                   unsigned int keylen)
33 {
34         struct shash_alg *shash = crypto_shash_alg(tfm);
35         unsigned long alignmask = crypto_shash_alignmask(tfm);
36         unsigned long absize;
37         u8 *buffer, *alignbuffer;
38         int err;
39
40         absize = keylen + (alignmask & ~(CRYPTO_MINALIGN - 1));
41         buffer = kmalloc(absize, GFP_KERNEL);
42         if (!buffer)
43                 return -ENOMEM;
44
45         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
46         memcpy(alignbuffer, key, keylen);
47         err = shash->setkey(tfm, alignbuffer, keylen);
48         kzfree(buffer);
49         return err;
50 }
51
52 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
53                         unsigned int keylen)
54 {
55         struct shash_alg *shash = crypto_shash_alg(tfm);
56         unsigned long alignmask = crypto_shash_alignmask(tfm);
57
58         if ((unsigned long)key & alignmask)
59                 return shash_setkey_unaligned(tfm, key, keylen);
60
61         return shash->setkey(tfm, key, keylen);
62 }
63 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
64
65 static inline unsigned int shash_align_buffer_size(unsigned len,
66                                                    unsigned long mask)
67 {
68         return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1));
69 }
70
71 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
72                                   unsigned int len)
73 {
74         struct crypto_shash *tfm = desc->tfm;
75         struct shash_alg *shash = crypto_shash_alg(tfm);
76         unsigned long alignmask = crypto_shash_alignmask(tfm);
77         unsigned int unaligned_len = alignmask + 1 -
78                                      ((unsigned long)data & alignmask);
79         u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)]
80                 __attribute__ ((aligned));
81         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
82         int err;
83
84         if (unaligned_len > len)
85                 unaligned_len = len;
86
87         memcpy(buf, data, unaligned_len);
88         err = shash->update(desc, buf, unaligned_len);
89         memset(buf, 0, unaligned_len);
90
91         return err ?:
92                shash->update(desc, data + unaligned_len, len - unaligned_len);
93 }
94
95 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
96                         unsigned int len)
97 {
98         struct crypto_shash *tfm = desc->tfm;
99         struct shash_alg *shash = crypto_shash_alg(tfm);
100         unsigned long alignmask = crypto_shash_alignmask(tfm);
101
102         if ((unsigned long)data & alignmask)
103                 return shash_update_unaligned(desc, data, len);
104
105         return shash->update(desc, data, len);
106 }
107 EXPORT_SYMBOL_GPL(crypto_shash_update);
108
109 static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
110 {
111         struct crypto_shash *tfm = desc->tfm;
112         unsigned long alignmask = crypto_shash_alignmask(tfm);
113         struct shash_alg *shash = crypto_shash_alg(tfm);
114         unsigned int ds = crypto_shash_digestsize(tfm);
115         u8 ubuf[shash_align_buffer_size(ds, alignmask)]
116                 __attribute__ ((aligned));
117         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
118         int err;
119
120         err = shash->final(desc, buf);
121         if (err)
122                 goto out;
123
124         memcpy(out, buf, ds);
125
126 out:
127         memset(buf, 0, ds);
128         return err;
129 }
130
131 int crypto_shash_final(struct shash_desc *desc, u8 *out)
132 {
133         struct crypto_shash *tfm = desc->tfm;
134         struct shash_alg *shash = crypto_shash_alg(tfm);
135         unsigned long alignmask = crypto_shash_alignmask(tfm);
136
137         if ((unsigned long)out & alignmask)
138                 return shash_final_unaligned(desc, out);
139
140         return shash->final(desc, out);
141 }
142 EXPORT_SYMBOL_GPL(crypto_shash_final);
143
144 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
145                                  unsigned int len, u8 *out)
146 {
147         return crypto_shash_update(desc, data, len) ?:
148                crypto_shash_final(desc, out);
149 }
150
151 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
152                        unsigned int len, u8 *out)
153 {
154         struct crypto_shash *tfm = desc->tfm;
155         struct shash_alg *shash = crypto_shash_alg(tfm);
156         unsigned long alignmask = crypto_shash_alignmask(tfm);
157
158         if (((unsigned long)data | (unsigned long)out) & alignmask)
159                 return shash_finup_unaligned(desc, data, len, out);
160
161         return shash->finup(desc, data, len, out);
162 }
163 EXPORT_SYMBOL_GPL(crypto_shash_finup);
164
165 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
166                                   unsigned int len, u8 *out)
167 {
168         return crypto_shash_init(desc) ?:
169                crypto_shash_finup(desc, data, len, out);
170 }
171
172 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
173                         unsigned int len, u8 *out)
174 {
175         struct crypto_shash *tfm = desc->tfm;
176         struct shash_alg *shash = crypto_shash_alg(tfm);
177         unsigned long alignmask = crypto_shash_alignmask(tfm);
178
179         if (((unsigned long)data | (unsigned long)out) & alignmask)
180                 return shash_digest_unaligned(desc, data, len, out);
181
182         return shash->digest(desc, data, len, out);
183 }
184 EXPORT_SYMBOL_GPL(crypto_shash_digest);
185
186 static int shash_default_export(struct shash_desc *desc, void *out)
187 {
188         memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
189         return 0;
190 }
191
192 static int shash_default_import(struct shash_desc *desc, const void *in)
193 {
194         memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
195         return 0;
196 }
197
198 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
199                               unsigned int keylen)
200 {
201         struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
202
203         return crypto_shash_setkey(*ctx, key, keylen);
204 }
205
206 static int shash_async_init(struct ahash_request *req)
207 {
208         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
209         struct shash_desc *desc = ahash_request_ctx(req);
210
211         desc->tfm = *ctx;
212         desc->flags = req->base.flags;
213
214         return crypto_shash_init(desc);
215 }
216
217 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
218 {
219         struct crypto_hash_walk walk;
220         int nbytes;
221
222         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
223              nbytes = crypto_hash_walk_done(&walk, nbytes))
224                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
225
226         return nbytes;
227 }
228 EXPORT_SYMBOL_GPL(shash_ahash_update);
229
230 static int shash_async_update(struct ahash_request *req)
231 {
232         return shash_ahash_update(req, ahash_request_ctx(req));
233 }
234
235 static int shash_async_final(struct ahash_request *req)
236 {
237         return crypto_shash_final(ahash_request_ctx(req), req->result);
238 }
239
240 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
241 {
242         struct crypto_hash_walk walk;
243         int nbytes;
244
245         nbytes = crypto_hash_walk_first(req, &walk);
246         if (!nbytes)
247                 return crypto_shash_final(desc, req->result);
248
249         do {
250                 nbytes = crypto_hash_walk_last(&walk) ?
251                          crypto_shash_finup(desc, walk.data, nbytes,
252                                             req->result) :
253                          crypto_shash_update(desc, walk.data, nbytes);
254                 nbytes = crypto_hash_walk_done(&walk, nbytes);
255         } while (nbytes > 0);
256
257         return nbytes;
258 }
259 EXPORT_SYMBOL_GPL(shash_ahash_finup);
260
261 static int shash_async_finup(struct ahash_request *req)
262 {
263         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
264         struct shash_desc *desc = ahash_request_ctx(req);
265
266         desc->tfm = *ctx;
267         desc->flags = req->base.flags;
268
269         return shash_ahash_finup(req, desc);
270 }
271
272 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
273 {
274         struct scatterlist *sg = req->src;
275         unsigned int offset = sg->offset;
276         unsigned int nbytes = req->nbytes;
277         int err;
278
279         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
280                 void *data;
281
282                 data = crypto_kmap(sg_page(sg), 0);
283                 err = crypto_shash_digest(desc, data + offset, nbytes,
284                                           req->result);
285                 crypto_kunmap(data, 0);
286                 crypto_yield(desc->flags);
287         } else
288                 err = crypto_shash_init(desc) ?:
289                       shash_ahash_finup(req, desc);
290
291         return err;
292 }
293 EXPORT_SYMBOL_GPL(shash_ahash_digest);
294
295 static int shash_async_digest(struct ahash_request *req)
296 {
297         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
298         struct shash_desc *desc = ahash_request_ctx(req);
299
300         desc->tfm = *ctx;
301         desc->flags = req->base.flags;
302
303         return shash_ahash_digest(req, desc);
304 }
305
306 static int shash_async_export(struct ahash_request *req, void *out)
307 {
308         return crypto_shash_export(ahash_request_ctx(req), out);
309 }
310
311 static int shash_async_import(struct ahash_request *req, const void *in)
312 {
313         return crypto_shash_import(ahash_request_ctx(req), in);
314 }
315
316 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
317 {
318         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
319
320         crypto_free_shash(*ctx);
321 }
322
323 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
324 {
325         struct crypto_alg *calg = tfm->__crt_alg;
326         struct shash_alg *alg = __crypto_shash_alg(calg);
327         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
328         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
329         struct crypto_shash *shash;
330
331         if (!crypto_mod_get(calg))
332                 return -EAGAIN;
333
334         shash = crypto_create_tfm(calg, &crypto_shash_type);
335         if (IS_ERR(shash)) {
336                 crypto_mod_put(calg);
337                 return PTR_ERR(shash);
338         }
339
340         *ctx = shash;
341         tfm->exit = crypto_exit_shash_ops_async;
342
343         crt->init = shash_async_init;
344         crt->update = shash_async_update;
345         crt->final = shash_async_final;
346         crt->finup = shash_async_finup;
347         crt->digest = shash_async_digest;
348
349         if (alg->setkey)
350                 crt->setkey = shash_async_setkey;
351         if (alg->export)
352                 crt->export = shash_async_export;
353         if (alg->import)
354                 crt->import = shash_async_import;
355
356         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
357
358         return 0;
359 }
360
361 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
362                                unsigned int keylen)
363 {
364         struct shash_desc **descp = crypto_hash_ctx(tfm);
365         struct shash_desc *desc = *descp;
366
367         return crypto_shash_setkey(desc->tfm, key, keylen);
368 }
369
370 static int shash_compat_init(struct hash_desc *hdesc)
371 {
372         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
373         struct shash_desc *desc = *descp;
374
375         desc->flags = hdesc->flags;
376
377         return crypto_shash_init(desc);
378 }
379
380 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
381                                unsigned int len)
382 {
383         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
384         struct shash_desc *desc = *descp;
385         struct crypto_hash_walk walk;
386         int nbytes;
387
388         for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len);
389              nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes))
390                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
391
392         return nbytes;
393 }
394
395 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
396 {
397         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
398
399         return crypto_shash_final(*descp, out);
400 }
401
402 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
403                                unsigned int nbytes, u8 *out)
404 {
405         unsigned int offset = sg->offset;
406         int err;
407
408         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
409                 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
410                 struct shash_desc *desc = *descp;
411                 void *data;
412
413                 desc->flags = hdesc->flags;
414
415                 data = crypto_kmap(sg_page(sg), 0);
416                 err = crypto_shash_digest(desc, data + offset, nbytes, out);
417                 crypto_kunmap(data, 0);
418                 crypto_yield(desc->flags);
419                 goto out;
420         }
421
422         err = shash_compat_init(hdesc);
423         if (err)
424                 goto out;
425
426         err = shash_compat_update(hdesc, sg, nbytes);
427         if (err)
428                 goto out;
429
430         err = shash_compat_final(hdesc, out);
431
432 out:
433         return err;
434 }
435
436 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
437 {
438         struct shash_desc **descp = crypto_tfm_ctx(tfm);
439         struct shash_desc *desc = *descp;
440
441         crypto_free_shash(desc->tfm);
442         kzfree(desc);
443 }
444
445 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
446 {
447         struct hash_tfm *crt = &tfm->crt_hash;
448         struct crypto_alg *calg = tfm->__crt_alg;
449         struct shash_alg *alg = __crypto_shash_alg(calg);
450         struct shash_desc **descp = crypto_tfm_ctx(tfm);
451         struct crypto_shash *shash;
452         struct shash_desc *desc;
453
454         if (!crypto_mod_get(calg))
455                 return -EAGAIN;
456
457         shash = crypto_create_tfm(calg, &crypto_shash_type);
458         if (IS_ERR(shash)) {
459                 crypto_mod_put(calg);
460                 return PTR_ERR(shash);
461         }
462
463         desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
464                        GFP_KERNEL);
465         if (!desc) {
466                 crypto_free_shash(shash);
467                 return -ENOMEM;
468         }
469
470         *descp = desc;
471         desc->tfm = shash;
472         tfm->exit = crypto_exit_shash_ops_compat;
473
474         crt->init = shash_compat_init;
475         crt->update = shash_compat_update;
476         crt->final  = shash_compat_final;
477         crt->digest = shash_compat_digest;
478         crt->setkey = shash_compat_setkey;
479
480         crt->digestsize = alg->digestsize;
481
482         return 0;
483 }
484
485 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
486 {
487         switch (mask & CRYPTO_ALG_TYPE_MASK) {
488         case CRYPTO_ALG_TYPE_HASH_MASK:
489                 return crypto_init_shash_ops_compat(tfm);
490         }
491
492         return -EINVAL;
493 }
494
495 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
496                                          u32 mask)
497 {
498         switch (mask & CRYPTO_ALG_TYPE_MASK) {
499         case CRYPTO_ALG_TYPE_HASH_MASK:
500                 return sizeof(struct shash_desc *);
501         }
502
503         return 0;
504 }
505
506 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
507 {
508         struct crypto_shash *hash = __crypto_shash_cast(tfm);
509
510         hash->descsize = crypto_shash_alg(hash)->descsize;
511         return 0;
512 }
513
514 static unsigned int crypto_shash_extsize(struct crypto_alg *alg)
515 {
516         return alg->cra_ctxsize;
517 }
518
519 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
520         __attribute__ ((unused));
521 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
522 {
523         struct shash_alg *salg = __crypto_shash_alg(alg);
524
525         seq_printf(m, "type         : shash\n");
526         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
527         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
528 }
529
530 static const struct crypto_type crypto_shash_type = {
531         .ctxsize = crypto_shash_ctxsize,
532         .extsize = crypto_shash_extsize,
533         .init = crypto_init_shash_ops,
534         .init_tfm = crypto_shash_init_tfm,
535 #ifdef CONFIG_PROC_FS
536         .show = crypto_shash_show,
537 #endif
538         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
539         .maskset = CRYPTO_ALG_TYPE_MASK,
540         .type = CRYPTO_ALG_TYPE_SHASH,
541         .tfmsize = offsetof(struct crypto_shash, base),
542 };
543
544 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
545                                         u32 mask)
546 {
547         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
548 }
549 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
550
551 static int shash_prepare_alg(struct shash_alg *alg)
552 {
553         struct crypto_alg *base = &alg->base;
554
555         if (alg->digestsize > PAGE_SIZE / 8 ||
556             alg->descsize > PAGE_SIZE / 8 ||
557             alg->statesize > PAGE_SIZE / 8)
558                 return -EINVAL;
559
560         base->cra_type = &crypto_shash_type;
561         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
562         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
563
564         if (!alg->finup)
565                 alg->finup = shash_finup_unaligned;
566         if (!alg->digest)
567                 alg->digest = shash_digest_unaligned;
568         if (!alg->export) {
569                 alg->export = shash_default_export;
570                 alg->import = shash_default_import;
571                 alg->statesize = alg->descsize;
572         }
573         if (!alg->setkey)
574                 alg->setkey = shash_no_setkey;
575
576         return 0;
577 }
578
579 int crypto_register_shash(struct shash_alg *alg)
580 {
581         struct crypto_alg *base = &alg->base;
582         int err;
583
584         err = shash_prepare_alg(alg);
585         if (err)
586                 return err;
587
588         return crypto_register_alg(base);
589 }
590 EXPORT_SYMBOL_GPL(crypto_register_shash);
591
592 int crypto_unregister_shash(struct shash_alg *alg)
593 {
594         return crypto_unregister_alg(&alg->base);
595 }
596 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
597
598 int shash_register_instance(struct crypto_template *tmpl,
599                             struct shash_instance *inst)
600 {
601         int err;
602
603         err = shash_prepare_alg(&inst->alg);
604         if (err)
605                 return err;
606
607         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
608 }
609 EXPORT_SYMBOL_GPL(shash_register_instance);
610
611 void shash_free_instance(struct crypto_instance *inst)
612 {
613         crypto_drop_spawn(crypto_instance_ctx(inst));
614         kfree(shash_instance(inst));
615 }
616 EXPORT_SYMBOL_GPL(shash_free_instance);
617
618 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
619                             struct shash_alg *alg,
620                             struct crypto_instance *inst)
621 {
622         return crypto_init_spawn2(&spawn->base, &alg->base, inst,
623                                   &crypto_shash_type);
624 }
625 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
626
627 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
628 {
629         struct crypto_alg *alg;
630
631         alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
632         return IS_ERR(alg) ? ERR_CAST(alg) :
633                container_of(alg, struct shash_alg, base);
634 }
635 EXPORT_SYMBOL_GPL(shash_attr_alg);
636
637 MODULE_LICENSE("GPL");
638 MODULE_DESCRIPTION("Synchronous cryptographic hash type");