crypto: af_alg - Forbid bind(2) when nokey child sockets are present
[pandora-kernel.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 #include <linux/cryptouser.h>
21 #include <net/netlink.h>
22
23 #include "internal.h"
24
25 static const struct crypto_type crypto_shash_type;
26
27 static int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
28                            unsigned int keylen)
29 {
30         return -ENOSYS;
31 }
32
33 static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
34                                   unsigned int keylen)
35 {
36         struct shash_alg *shash = crypto_shash_alg(tfm);
37         unsigned long alignmask = crypto_shash_alignmask(tfm);
38         unsigned long absize;
39         u8 *buffer, *alignbuffer;
40         int err;
41
42         absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
43         buffer = kmalloc(absize, GFP_KERNEL);
44         if (!buffer)
45                 return -ENOMEM;
46
47         alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
48         memcpy(alignbuffer, key, keylen);
49         err = shash->setkey(tfm, alignbuffer, keylen);
50         kzfree(buffer);
51         return err;
52 }
53
54 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
55                         unsigned int keylen)
56 {
57         struct shash_alg *shash = crypto_shash_alg(tfm);
58         unsigned long alignmask = crypto_shash_alignmask(tfm);
59
60         if ((unsigned long)key & alignmask)
61                 return shash_setkey_unaligned(tfm, key, keylen);
62
63         return shash->setkey(tfm, key, keylen);
64 }
65 EXPORT_SYMBOL_GPL(crypto_shash_setkey);
66
67 static inline unsigned int shash_align_buffer_size(unsigned len,
68                                                    unsigned long mask)
69 {
70         return len + (mask & ~(__alignof__(u8 __attribute__ ((aligned))) - 1));
71 }
72
73 static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
74                                   unsigned int len)
75 {
76         struct crypto_shash *tfm = desc->tfm;
77         struct shash_alg *shash = crypto_shash_alg(tfm);
78         unsigned long alignmask = crypto_shash_alignmask(tfm);
79         unsigned int unaligned_len = alignmask + 1 -
80                                      ((unsigned long)data & alignmask);
81         u8 ubuf[shash_align_buffer_size(unaligned_len, alignmask)]
82                 __attribute__ ((aligned));
83         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
84         int err;
85
86         if (unaligned_len > len)
87                 unaligned_len = len;
88
89         memcpy(buf, data, unaligned_len);
90         err = shash->update(desc, buf, unaligned_len);
91         memset(buf, 0, unaligned_len);
92
93         return err ?:
94                shash->update(desc, data + unaligned_len, len - unaligned_len);
95 }
96
97 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
98                         unsigned int len)
99 {
100         struct crypto_shash *tfm = desc->tfm;
101         struct shash_alg *shash = crypto_shash_alg(tfm);
102         unsigned long alignmask = crypto_shash_alignmask(tfm);
103
104         if ((unsigned long)data & alignmask)
105                 return shash_update_unaligned(desc, data, len);
106
107         return shash->update(desc, data, len);
108 }
109 EXPORT_SYMBOL_GPL(crypto_shash_update);
110
111 static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
112 {
113         struct crypto_shash *tfm = desc->tfm;
114         unsigned long alignmask = crypto_shash_alignmask(tfm);
115         struct shash_alg *shash = crypto_shash_alg(tfm);
116         unsigned int ds = crypto_shash_digestsize(tfm);
117         u8 ubuf[shash_align_buffer_size(ds, alignmask)]
118                 __attribute__ ((aligned));
119         u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
120         int err;
121
122         err = shash->final(desc, buf);
123         if (err)
124                 goto out;
125
126         memcpy(out, buf, ds);
127
128 out:
129         memset(buf, 0, ds);
130         return err;
131 }
132
133 int crypto_shash_final(struct shash_desc *desc, u8 *out)
134 {
135         struct crypto_shash *tfm = desc->tfm;
136         struct shash_alg *shash = crypto_shash_alg(tfm);
137         unsigned long alignmask = crypto_shash_alignmask(tfm);
138
139         if ((unsigned long)out & alignmask)
140                 return shash_final_unaligned(desc, out);
141
142         return shash->final(desc, out);
143 }
144 EXPORT_SYMBOL_GPL(crypto_shash_final);
145
146 static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
147                                  unsigned int len, u8 *out)
148 {
149         return crypto_shash_update(desc, data, len) ?:
150                crypto_shash_final(desc, out);
151 }
152
153 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
154                        unsigned int len, u8 *out)
155 {
156         struct crypto_shash *tfm = desc->tfm;
157         struct shash_alg *shash = crypto_shash_alg(tfm);
158         unsigned long alignmask = crypto_shash_alignmask(tfm);
159
160         if (((unsigned long)data | (unsigned long)out) & alignmask)
161                 return shash_finup_unaligned(desc, data, len, out);
162
163         return shash->finup(desc, data, len, out);
164 }
165 EXPORT_SYMBOL_GPL(crypto_shash_finup);
166
167 static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
168                                   unsigned int len, u8 *out)
169 {
170         return crypto_shash_init(desc) ?:
171                crypto_shash_finup(desc, data, len, out);
172 }
173
174 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
175                         unsigned int len, u8 *out)
176 {
177         struct crypto_shash *tfm = desc->tfm;
178         struct shash_alg *shash = crypto_shash_alg(tfm);
179         unsigned long alignmask = crypto_shash_alignmask(tfm);
180
181         if (((unsigned long)data | (unsigned long)out) & alignmask)
182                 return shash_digest_unaligned(desc, data, len, out);
183
184         return shash->digest(desc, data, len, out);
185 }
186 EXPORT_SYMBOL_GPL(crypto_shash_digest);
187
188 static int shash_default_export(struct shash_desc *desc, void *out)
189 {
190         memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
191         return 0;
192 }
193
194 static int shash_default_import(struct shash_desc *desc, const void *in)
195 {
196         memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
197         return 0;
198 }
199
200 static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
201                               unsigned int keylen)
202 {
203         struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
204
205         return crypto_shash_setkey(*ctx, key, keylen);
206 }
207
208 static int shash_async_init(struct ahash_request *req)
209 {
210         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
211         struct shash_desc *desc = ahash_request_ctx(req);
212
213         desc->tfm = *ctx;
214         desc->flags = req->base.flags;
215
216         return crypto_shash_init(desc);
217 }
218
219 int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
220 {
221         struct crypto_hash_walk walk;
222         int nbytes;
223
224         for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
225              nbytes = crypto_hash_walk_done(&walk, nbytes))
226                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
227
228         return nbytes;
229 }
230 EXPORT_SYMBOL_GPL(shash_ahash_update);
231
232 static int shash_async_update(struct ahash_request *req)
233 {
234         return shash_ahash_update(req, ahash_request_ctx(req));
235 }
236
237 static int shash_async_final(struct ahash_request *req)
238 {
239         return crypto_shash_final(ahash_request_ctx(req), req->result);
240 }
241
242 int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
243 {
244         struct crypto_hash_walk walk;
245         int nbytes;
246
247         nbytes = crypto_hash_walk_first(req, &walk);
248         if (!nbytes)
249                 return crypto_shash_final(desc, req->result);
250
251         do {
252                 nbytes = crypto_hash_walk_last(&walk) ?
253                          crypto_shash_finup(desc, walk.data, nbytes,
254                                             req->result) :
255                          crypto_shash_update(desc, walk.data, nbytes);
256                 nbytes = crypto_hash_walk_done(&walk, nbytes);
257         } while (nbytes > 0);
258
259         return nbytes;
260 }
261 EXPORT_SYMBOL_GPL(shash_ahash_finup);
262
263 static int shash_async_finup(struct ahash_request *req)
264 {
265         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
266         struct shash_desc *desc = ahash_request_ctx(req);
267
268         desc->tfm = *ctx;
269         desc->flags = req->base.flags;
270
271         return shash_ahash_finup(req, desc);
272 }
273
274 int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
275 {
276         struct scatterlist *sg = req->src;
277         unsigned int offset = sg->offset;
278         unsigned int nbytes = req->nbytes;
279         int err;
280
281         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
282                 void *data;
283
284                 data = crypto_kmap(sg_page(sg), 0);
285                 err = crypto_shash_digest(desc, data + offset, nbytes,
286                                           req->result);
287                 crypto_kunmap(data, 0);
288                 crypto_yield(desc->flags);
289         } else
290                 err = crypto_shash_init(desc) ?:
291                       shash_ahash_finup(req, desc);
292
293         return err;
294 }
295 EXPORT_SYMBOL_GPL(shash_ahash_digest);
296
297 static int shash_async_digest(struct ahash_request *req)
298 {
299         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
300         struct shash_desc *desc = ahash_request_ctx(req);
301
302         desc->tfm = *ctx;
303         desc->flags = req->base.flags;
304
305         return shash_ahash_digest(req, desc);
306 }
307
308 static int shash_async_export(struct ahash_request *req, void *out)
309 {
310         return crypto_shash_export(ahash_request_ctx(req), out);
311 }
312
313 static int shash_async_import(struct ahash_request *req, const void *in)
314 {
315         struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
316         struct shash_desc *desc = ahash_request_ctx(req);
317
318         desc->tfm = *ctx;
319         desc->flags = req->base.flags;
320
321         return crypto_shash_import(desc, in);
322 }
323
324 static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
325 {
326         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
327
328         crypto_free_shash(*ctx);
329 }
330
331 int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
332 {
333         struct crypto_alg *calg = tfm->__crt_alg;
334         struct shash_alg *alg = __crypto_shash_alg(calg);
335         struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
336         struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
337         struct crypto_shash *shash;
338
339         if (!crypto_mod_get(calg))
340                 return -EAGAIN;
341
342         shash = crypto_create_tfm(calg, &crypto_shash_type);
343         if (IS_ERR(shash)) {
344                 crypto_mod_put(calg);
345                 return PTR_ERR(shash);
346         }
347
348         *ctx = shash;
349         tfm->exit = crypto_exit_shash_ops_async;
350
351         crt->init = shash_async_init;
352         crt->update = shash_async_update;
353         crt->final = shash_async_final;
354         crt->finup = shash_async_finup;
355         crt->digest = shash_async_digest;
356
357         if (alg->setkey) {
358                 crt->setkey = shash_async_setkey;
359                 crt->has_setkey = true;
360         }
361         if (alg->export)
362                 crt->export = shash_async_export;
363         if (alg->import)
364                 crt->import = shash_async_import;
365
366         crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
367
368         return 0;
369 }
370
371 static int shash_compat_setkey(struct crypto_hash *tfm, const u8 *key,
372                                unsigned int keylen)
373 {
374         struct shash_desc **descp = crypto_hash_ctx(tfm);
375         struct shash_desc *desc = *descp;
376
377         return crypto_shash_setkey(desc->tfm, key, keylen);
378 }
379
380 static int shash_compat_init(struct hash_desc *hdesc)
381 {
382         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
383         struct shash_desc *desc = *descp;
384
385         desc->flags = hdesc->flags;
386
387         return crypto_shash_init(desc);
388 }
389
390 static int shash_compat_update(struct hash_desc *hdesc, struct scatterlist *sg,
391                                unsigned int len)
392 {
393         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
394         struct shash_desc *desc = *descp;
395         struct crypto_hash_walk walk;
396         int nbytes;
397
398         for (nbytes = crypto_hash_walk_first_compat(hdesc, &walk, sg, len);
399              nbytes > 0; nbytes = crypto_hash_walk_done(&walk, nbytes))
400                 nbytes = crypto_shash_update(desc, walk.data, nbytes);
401
402         return nbytes;
403 }
404
405 static int shash_compat_final(struct hash_desc *hdesc, u8 *out)
406 {
407         struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
408
409         return crypto_shash_final(*descp, out);
410 }
411
412 static int shash_compat_digest(struct hash_desc *hdesc, struct scatterlist *sg,
413                                unsigned int nbytes, u8 *out)
414 {
415         unsigned int offset = sg->offset;
416         int err;
417
418         if (nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset)) {
419                 struct shash_desc **descp = crypto_hash_ctx(hdesc->tfm);
420                 struct shash_desc *desc = *descp;
421                 void *data;
422
423                 desc->flags = hdesc->flags;
424
425                 data = crypto_kmap(sg_page(sg), 0);
426                 err = crypto_shash_digest(desc, data + offset, nbytes, out);
427                 crypto_kunmap(data, 0);
428                 crypto_yield(desc->flags);
429                 goto out;
430         }
431
432         err = shash_compat_init(hdesc);
433         if (err)
434                 goto out;
435
436         err = shash_compat_update(hdesc, sg, nbytes);
437         if (err)
438                 goto out;
439
440         err = shash_compat_final(hdesc, out);
441
442 out:
443         return err;
444 }
445
446 static void crypto_exit_shash_ops_compat(struct crypto_tfm *tfm)
447 {
448         struct shash_desc **descp = crypto_tfm_ctx(tfm);
449         struct shash_desc *desc = *descp;
450
451         crypto_free_shash(desc->tfm);
452         kzfree(desc);
453 }
454
455 static int crypto_init_shash_ops_compat(struct crypto_tfm *tfm)
456 {
457         struct hash_tfm *crt = &tfm->crt_hash;
458         struct crypto_alg *calg = tfm->__crt_alg;
459         struct shash_alg *alg = __crypto_shash_alg(calg);
460         struct shash_desc **descp = crypto_tfm_ctx(tfm);
461         struct crypto_shash *shash;
462         struct shash_desc *desc;
463
464         if (!crypto_mod_get(calg))
465                 return -EAGAIN;
466
467         shash = crypto_create_tfm(calg, &crypto_shash_type);
468         if (IS_ERR(shash)) {
469                 crypto_mod_put(calg);
470                 return PTR_ERR(shash);
471         }
472
473         desc = kmalloc(sizeof(*desc) + crypto_shash_descsize(shash),
474                        GFP_KERNEL);
475         if (!desc) {
476                 crypto_free_shash(shash);
477                 return -ENOMEM;
478         }
479
480         *descp = desc;
481         desc->tfm = shash;
482         tfm->exit = crypto_exit_shash_ops_compat;
483
484         crt->init = shash_compat_init;
485         crt->update = shash_compat_update;
486         crt->final  = shash_compat_final;
487         crt->digest = shash_compat_digest;
488         crt->setkey = shash_compat_setkey;
489
490         crt->digestsize = alg->digestsize;
491
492         return 0;
493 }
494
495 static int crypto_init_shash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
496 {
497         switch (mask & CRYPTO_ALG_TYPE_MASK) {
498         case CRYPTO_ALG_TYPE_HASH_MASK:
499                 return crypto_init_shash_ops_compat(tfm);
500         }
501
502         return -EINVAL;
503 }
504
505 static unsigned int crypto_shash_ctxsize(struct crypto_alg *alg, u32 type,
506                                          u32 mask)
507 {
508         switch (mask & CRYPTO_ALG_TYPE_MASK) {
509         case CRYPTO_ALG_TYPE_HASH_MASK:
510                 return sizeof(struct shash_desc *);
511         }
512
513         return 0;
514 }
515
516 static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
517 {
518         struct crypto_shash *hash = __crypto_shash_cast(tfm);
519
520         hash->descsize = crypto_shash_alg(hash)->descsize;
521         return 0;
522 }
523
524 static unsigned int crypto_shash_extsize(struct crypto_alg *alg)
525 {
526         return alg->cra_ctxsize;
527 }
528
529 #ifdef CONFIG_NET
530 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
531 {
532         struct crypto_report_hash rhash;
533         struct shash_alg *salg = __crypto_shash_alg(alg);
534
535         strncpy(rhash.type, "shash", sizeof(rhash.type));
536
537         rhash.blocksize = alg->cra_blocksize;
538         rhash.digestsize = salg->digestsize;
539
540         NLA_PUT(skb, CRYPTOCFGA_REPORT_HASH,
541                 sizeof(struct crypto_report_hash), &rhash);
542
543         return 0;
544
545 nla_put_failure:
546         return -EMSGSIZE;
547 }
548 #else
549 static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
550 {
551         return -ENOSYS;
552 }
553 #endif
554
555 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
556         __attribute__ ((unused));
557 static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
558 {
559         struct shash_alg *salg = __crypto_shash_alg(alg);
560
561         seq_printf(m, "type         : shash\n");
562         seq_printf(m, "blocksize    : %u\n", alg->cra_blocksize);
563         seq_printf(m, "digestsize   : %u\n", salg->digestsize);
564 }
565
566 static const struct crypto_type crypto_shash_type = {
567         .ctxsize = crypto_shash_ctxsize,
568         .extsize = crypto_shash_extsize,
569         .init = crypto_init_shash_ops,
570         .init_tfm = crypto_shash_init_tfm,
571 #ifdef CONFIG_PROC_FS
572         .show = crypto_shash_show,
573 #endif
574         .report = crypto_shash_report,
575         .maskclear = ~CRYPTO_ALG_TYPE_MASK,
576         .maskset = CRYPTO_ALG_TYPE_MASK,
577         .type = CRYPTO_ALG_TYPE_SHASH,
578         .tfmsize = offsetof(struct crypto_shash, base),
579 };
580
581 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
582                                         u32 mask)
583 {
584         return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
585 }
586 EXPORT_SYMBOL_GPL(crypto_alloc_shash);
587
588 static int shash_prepare_alg(struct shash_alg *alg)
589 {
590         struct crypto_alg *base = &alg->base;
591
592         if (alg->digestsize > PAGE_SIZE / 8 ||
593             alg->descsize > PAGE_SIZE / 8 ||
594             alg->statesize > PAGE_SIZE / 8)
595                 return -EINVAL;
596
597         base->cra_type = &crypto_shash_type;
598         base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
599         base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
600
601         if (!alg->finup)
602                 alg->finup = shash_finup_unaligned;
603         if (!alg->digest)
604                 alg->digest = shash_digest_unaligned;
605         if (!alg->export) {
606                 alg->export = shash_default_export;
607                 alg->import = shash_default_import;
608                 alg->statesize = alg->descsize;
609         }
610         if (!alg->setkey)
611                 alg->setkey = shash_no_setkey;
612
613         return 0;
614 }
615
616 int crypto_register_shash(struct shash_alg *alg)
617 {
618         struct crypto_alg *base = &alg->base;
619         int err;
620
621         err = shash_prepare_alg(alg);
622         if (err)
623                 return err;
624
625         return crypto_register_alg(base);
626 }
627 EXPORT_SYMBOL_GPL(crypto_register_shash);
628
629 int crypto_unregister_shash(struct shash_alg *alg)
630 {
631         return crypto_unregister_alg(&alg->base);
632 }
633 EXPORT_SYMBOL_GPL(crypto_unregister_shash);
634
635 int shash_register_instance(struct crypto_template *tmpl,
636                             struct shash_instance *inst)
637 {
638         int err;
639
640         err = shash_prepare_alg(&inst->alg);
641         if (err)
642                 return err;
643
644         return crypto_register_instance(tmpl, shash_crypto_instance(inst));
645 }
646 EXPORT_SYMBOL_GPL(shash_register_instance);
647
648 void shash_free_instance(struct crypto_instance *inst)
649 {
650         crypto_drop_spawn(crypto_instance_ctx(inst));
651         kfree(shash_instance(inst));
652 }
653 EXPORT_SYMBOL_GPL(shash_free_instance);
654
655 int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
656                             struct shash_alg *alg,
657                             struct crypto_instance *inst)
658 {
659         return crypto_init_spawn2(&spawn->base, &alg->base, inst,
660                                   &crypto_shash_type);
661 }
662 EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
663
664 struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
665 {
666         struct crypto_alg *alg;
667
668         alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
669         return IS_ERR(alg) ? ERR_CAST(alg) :
670                container_of(alg, struct shash_alg, base);
671 }
672 EXPORT_SYMBOL_GPL(shash_attr_alg);
673
674 MODULE_LICENSE("GPL");
675 MODULE_DESCRIPTION("Synchronous cryptographic hash type");