crypto: ahash - Remove old_ahash_alg
[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         memset(alignbuffer, 0, keylen);
49         kfree(buffer);
50         return err;
51 }
52
53 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
54                         unsigned int keylen)
55 {
56         struct shash_alg *shash = crypto_shash_alg(tfm);
57         unsigned long alignmask = crypto_shash_alignmask(tfm);
58
59         if ((unsigned long)key & alignmask)
60                 return shash_setkey_unaligned(tfm, key, keylen);
61
62         return shash->setkey(tfm, key, keylen);
63 }
64 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
65
66 static inline unsigned int shash_align_buffer_size(unsigned len,
67                                                    unsigned long mask)
68 {
69         return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1));
70 }
71
72 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
73                                   unsigned int len)
74 {
75         struct crypto_shash *tfm = desc->tfm;
76         struct shash_alg *shash = crypto_shash_alg(tfm);
77         unsigned long alignmask = crypto_shash_alignmask(tfm);
78         unsigned int unaligned_len = alignmask + 1 -
79                                      ((unsigned long)data & alignmask);
80         u8 buf[shash_align_buffer_size(unaligned_len, alignmask)]
81                 __attribute__ ((aligned));
82
83         if (unaligned_len > len)
84                 unaligned_len = len;
85
86         memcpy(buf, data, unaligned_len);
87
88         return shash->update(desc, buf, unaligned_len) ?:
89                shash->update(desc, data + unaligned_len, len - unaligned_len);
90 }
91
92 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
93                         unsigned int len)
94 {
95         struct crypto_shash *tfm = desc->tfm;
96         struct shash_alg *shash = crypto_shash_alg(tfm);
97         unsigned long alignmask = crypto_shash_alignmask(tfm);
98
99         if ((unsigned long)data & alignmask)
100                 return shash_update_unaligned(desc, data, len);
101
102         return shash->update(desc, data, len);
103 }
104 EXPORT_SYMBOL_GPL(crypto_shash_update);
105
106 static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
107 {
108         struct crypto_shash *tfm = desc->tfm;
109         unsigned long alignmask = crypto_shash_alignmask(tfm);
110         struct shash_alg *shash = crypto_shash_alg(tfm);
111         unsigned int ds = crypto_shash_digestsize(tfm);
112         u8 buf[shash_align_buffer_size(ds, alignmask)]
113                 __attribute__ ((aligned));
114         int err;
115
116         err = shash->final(desc, buf);
117         memcpy(out, buf, ds);
118         return err;
119 }
120
121 int crypto_shash_final(struct shash_desc *desc, u8 *out)
122 {
123         struct crypto_shash *tfm = desc->tfm;
124         struct shash_alg *shash = crypto_shash_alg(tfm);
125         unsigned long alignmask = crypto_shash_alignmask(tfm);
126
127         if ((unsigned long)out & alignmask)
128                 return shash_final_unaligned(desc, out);
129
130         return shash->final(desc, out);
131 }
132 EXPORT_SYMBOL_GPL(crypto_shash_final);
133
134 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
135                                  unsigned int len, u8 *out)
136 {
137         return crypto_shash_update(desc, data, len) ?:
138                crypto_shash_final(desc, out);
139 }
140
141 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
142                        unsigned int len, u8 *out)
143 {
144         struct crypto_shash *tfm = desc->tfm;
145         struct shash_alg *shash = crypto_shash_alg(tfm);
146         unsigned long alignmask = crypto_shash_alignmask(tfm);
147
148         if (((unsigned long)data | (unsigned long)out) & alignmask)
149                 return shash_finup_unaligned(desc, data, len, out);
150
151         return shash->finup(desc, data, len, out);
152 }
153 EXPORT_SYMBOL_GPL(crypto_shash_finup);
154
155 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
156                                   unsigned int len, u8 *out)
157 {
158         return crypto_shash_init(desc) ?:
159                crypto_shash_finup(desc, data, len, out);
160 }
161
162 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
163                         unsigned int len, u8 *out)
164 {
165         struct crypto_shash *tfm = desc->tfm;
166         struct shash_alg *shash = crypto_shash_alg(tfm);
167         unsigned long alignmask = crypto_shash_alignmask(tfm);
168
169         if (((unsigned long)data | (unsigned long)out) & alignmask)
170                 return shash_digest_unaligned(desc, data, len, out);
171
172         return shash->digest(desc, data, len, out);
173 }
174 EXPORT_SYMBOL_GPL(crypto_shash_digest);
175
176 static int shash_no_export(struct shash_desc *desc, void *out)
177 {
178         return -ENOSYS;
179 }
180
181 static int shash_no_import(struct shash_desc *desc, const void *in)
182 {
183         return -ENOSYS;
184 }
185
186 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
187                               unsigned int keylen)
188 {
189         struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
190
191         return crypto_shash_setkey(*ctx, key, keylen);
192 }
193
194 static int shash_async_init(struct ahash_request *req)
195 {
196         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
197         struct shash_desc *desc = ahash_request_ctx(req);
198
199         desc->tfm = *ctx;
200         desc->flags = req->base.flags;
201
202         return crypto_shash_init(desc);
203 }
204
205 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
206 {
207         struct crypto_hash_walk walk;
208         int nbytes;
209
210         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
211              nbytes = crypto_hash_walk_done(&walk, nbytes))
212                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
213
214         return nbytes;
215 }
216 EXPORT_SYMBOL_GPL(shash_ahash_update);
217
218 static int shash_async_update(struct ahash_request *req)
219 {
220         return shash_ahash_update(req, ahash_request_ctx(req));
221 }
222
223 static int shash_async_final(struct ahash_request *req)
224 {
225         return crypto_shash_final(ahash_request_ctx(req), req->result);
226 }
227
228 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
229 {
230         struct scatterlist *sg = req->src;
231         unsigned int offset = sg->offset;
232         unsigned int nbytes = req->nbytes;
233         int err;
234
235         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
236                 void *data;
237
238                 data = crypto_kmap(sg_page(sg), 0);
239                 err = crypto_shash_digest(desc, data + offset, nbytes,
240                                           req->result);
241                 crypto_kunmap(data, 0);
242                 crypto_yield(desc->flags);
243         } else
244                 err = crypto_shash_init(desc) ?:
245                       shash_ahash_update(req, desc) ?:
246                       crypto_shash_final(desc, req->result);
247
248         return err;
249 }
250 EXPORT_SYMBOL_GPL(shash_ahash_digest);
251
252 static int shash_async_digest(struct ahash_request *req)
253 {
254         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
255         struct shash_desc *desc = ahash_request_ctx(req);
256
257         desc->tfm = *ctx;
258         desc->flags = req->base.flags;
259
260         return shash_ahash_digest(req, desc);
261 }
262
263 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
264 {
265         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
266
267         crypto_free_shash(*ctx);
268 }
269
270 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
271 {
272         struct crypto_alg *calg = tfm->__crt_alg;
273         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
274         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
275         struct crypto_shash *shash;
276
277         if (!crypto_mod_get(calg))
278                 return -EAGAIN;
279
280         shash = crypto_create_tfm(calg, &crypto_shash_type);
281         if (IS_ERR(shash)) {
282                 crypto_mod_put(calg);
283                 return PTR_ERR(shash);
284         }
285
286         *ctx = shash;
287         tfm->exit = crypto_exit_shash_ops_async;
288
289         crt->init = shash_async_init;
290         crt->update = shash_async_update;
291         crt->final  = shash_async_final;
292         crt->digest = shash_async_digest;
293         crt->setkey = shash_async_setkey;
294
295         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
296
297         return 0;
298 }
299
300 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
301                                unsigned int keylen)
302 {
303         struct shash_desc **descp = crypto_hash_ctx(tfm);
304         struct shash_desc *desc = *descp;
305
306         return crypto_shash_setkey(desc->tfm, key, keylen);
307 }
308
309 static int shash_compat_init(struct hash_desc *hdesc)
310 {
311         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
312         struct shash_desc *desc = *descp;
313
314         desc->flags = hdesc->flags;
315
316         return crypto_shash_init(desc);
317 }
318
319 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
320                                unsigned int len)
321 {
322         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
323         struct shash_desc *desc = *descp;
324         struct crypto_hash_walk walk;
325         int nbytes;
326
327         for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len);
328              nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes))
329                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
330
331         return nbytes;
332 }
333
334 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
335 {
336         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
337
338         return crypto_shash_final(*descp, out);
339 }
340
341 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
342                                unsigned int nbytes, u8 *out)
343 {
344         unsigned int offset = sg->offset;
345         int err;
346
347         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
348                 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
349                 struct shash_desc *desc = *descp;
350                 void *data;
351
352                 desc->flags = hdesc->flags;
353
354                 data = crypto_kmap(sg_page(sg), 0);
355                 err = crypto_shash_digest(desc, data + offset, nbytes, out);
356                 crypto_kunmap(data, 0);
357                 crypto_yield(desc->flags);
358                 goto out;
359         }
360
361         err = shash_compat_init(hdesc);
362         if (err)
363                 goto out;
364
365         err = shash_compat_update(hdesc, sg, nbytes);
366         if (err)
367                 goto out;
368
369         err = shash_compat_final(hdesc, out);
370
371 out:
372         return err;
373 }
374
375 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
376 {
377         struct shash_desc **descp = crypto_tfm_ctx(tfm);
378         struct shash_desc *desc = *descp;
379
380         crypto_free_shash(desc->tfm);
381         kzfree(desc);
382 }
383
384 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
385 {
386         struct hash_tfm *crt = &tfm->crt_hash;
387         struct crypto_alg *calg = tfm->__crt_alg;
388         struct shash_alg *alg = __crypto_shash_alg(calg);
389         struct shash_desc **descp = crypto_tfm_ctx(tfm);
390         struct crypto_shash *shash;
391         struct shash_desc *desc;
392
393         if (!crypto_mod_get(calg))
394                 return -EAGAIN;
395
396         shash = crypto_create_tfm(calg, &crypto_shash_type);
397         if (IS_ERR(shash)) {
398                 crypto_mod_put(calg);
399                 return PTR_ERR(shash);
400         }
401
402         desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
403                        GFP_KERNEL);
404         if (!desc) {
405                 crypto_free_shash(shash);
406                 return -ENOMEM;
407         }
408
409         *descp = desc;
410         desc->tfm = shash;
411         tfm->exit = crypto_exit_shash_ops_compat;
412
413         crt->init = shash_compat_init;
414         crt->update = shash_compat_update;
415         crt->final  = shash_compat_final;
416         crt->digest = shash_compat_digest;
417         crt->setkey = shash_compat_setkey;
418
419         crt->digestsize = alg->digestsize;
420
421         return 0;
422 }
423
424 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
425 {
426         switch (mask & CRYPTO_ALG_TYPE_MASK) {
427         case CRYPTO_ALG_TYPE_HASH_MASK:
428                 return crypto_init_shash_ops_compat(tfm);
429         }
430
431         return -EINVAL;
432 }
433
434 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
435                                          u32 mask)
436 {
437         switch (mask & CRYPTO_ALG_TYPE_MASK) {
438         case CRYPTO_ALG_TYPE_HASH_MASK:
439                 return sizeof(struct shash_desc *);
440         }
441
442         return 0;
443 }
444
445 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
446 {
447         struct crypto_shash *hash = __crypto_shash_cast(tfm);
448
449         hash->descsize = crypto_shash_alg(hash)->descsize;
450         return 0;
451 }
452
453 static unsigned int crypto_shash_extsize(struct crypto_alg *alg)
454 {
455         return alg->cra_ctxsize;
456 }
457
458 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
459         __attribute__ ((unused));
460 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
461 {
462         struct shash_alg *salg = __crypto_shash_alg(alg);
463
464         seq_printf(m, "type         : shash\n");
465         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
466         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
467 }
468
469 static const struct crypto_type crypto_shash_type = {
470         .ctxsize = crypto_shash_ctxsize,
471         .extsize = crypto_shash_extsize,
472         .init = crypto_init_shash_ops,
473         .init_tfm = crypto_shash_init_tfm,
474 #ifdef CONFIG_PROC_FS
475         .show = crypto_shash_show,
476 #endif
477         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
478         .maskset = CRYPTO_ALG_TYPE_MASK,
479         .type = CRYPTO_ALG_TYPE_SHASH,
480         .tfmsize = offsetof(struct crypto_shash, base),
481 };
482
483 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
484                                         u32 mask)
485 {
486         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
487 }
488 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
489
490 static int shash_prepare_alg(struct shash_alg *alg)
491 {
492         struct crypto_alg *base = &alg->base;
493
494         if (alg->digestsize > PAGE_SIZE / 8 ||
495             alg->descsize > PAGE_SIZE / 8 ||
496             alg->statesize > PAGE_SIZE / 8)
497                 return -EINVAL;
498
499         base->cra_type = &crypto_shash_type;
500         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
501         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
502
503         if (!alg->finup)
504                 alg->finup = shash_finup_unaligned;
505         if (!alg->digest)
506                 alg->digest = shash_digest_unaligned;
507         if (!alg->import)
508                 alg->import = shash_no_import;
509         if (!alg->export)
510                 alg->export = shash_no_export;
511         if (!alg->setkey)
512                 alg->setkey = shash_no_setkey;
513
514         return 0;
515 }
516
517 int crypto_register_shash(struct shash_alg *alg)
518 {
519         struct crypto_alg *base = &alg->base;
520         int err;
521
522         err = shash_prepare_alg(alg);
523         if (err)
524                 return err;
525
526         return crypto_register_alg(base);
527 }
528 EXPORT_SYMBOL_GPL(crypto_register_shash);
529
530 int crypto_unregister_shash(struct shash_alg *alg)
531 {
532         return crypto_unregister_alg(&alg->base);
533 }
534 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
535
536 int shash_register_instance(struct crypto_template *tmpl,
537                             struct shash_instance *inst)
538 {
539         int err;
540
541         err = shash_prepare_alg(&inst->alg);
542         if (err)
543                 return err;
544
545         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
546 }
547 EXPORT_SYMBOL_GPL(shash_register_instance);
548
549 void shash_free_instance(struct crypto_instance *inst)
550 {
551         crypto_drop_spawn(crypto_instance_ctx(inst));
552         kfree(shash_instance(inst));
553 }
554 EXPORT_SYMBOL_GPL(shash_free_instance);
555
556 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
557                             struct shash_alg *alg,
558                             struct crypto_instance *inst)
559 {
560         return crypto_init_spawn2(&spawn->base, &alg->base, inst,
561                                   &crypto_shash_type);
562 }
563 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
564
565 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
566 {
567         struct crypto_alg *alg;
568
569         alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
570         return IS_ERR(alg) ? ERR_CAST(alg) :
571                container_of(alg, struct shash_alg, base);
572 }
573 EXPORT_SYMBOL_GPL(shash_attr_alg);
574
575 MODULE_LICENSE("GPL");
576 MODULE_DESCRIPTION("Synchronous cryptographic hash type");