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#include <linux/compiler.h>
23
24#include "internal.h"
25
26static const struct crypto_type crypto_shash_type;
27
28int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
29 unsigned int keylen)
30{
31 return -ENOSYS;
32}
33EXPORT_SYMBOL_GPL(shash_no_setkey);
34
35static int shash_setkey_unaligned(struct crypto_shash *tfm, const u8 *key,
36 unsigned int keylen)
37{
38 struct shash_alg *shash = crypto_shash_alg(tfm);
39 unsigned long alignmask = crypto_shash_alignmask(tfm);
40 unsigned long absize;
41 u8 *buffer, *alignbuffer;
42 int err;
43
44 absize = keylen + (alignmask & ~(crypto_tfm_ctx_alignment() - 1));
45 buffer = kmalloc(absize, GFP_ATOMIC);
46 if (!buffer)
47 return -ENOMEM;
48
49 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
50 memcpy(alignbuffer, key, keylen);
51 err = shash->setkey(tfm, alignbuffer, keylen);
52 kzfree(buffer);
53 return err;
54}
55
56static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg)
57{
58 if (crypto_shash_alg_has_setkey(alg) &&
59 !(alg->base.cra_flags & CRYPTO_ALG_OPTIONAL_KEY))
60 crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
61}
62
63int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
64 unsigned int keylen)
65{
66 struct shash_alg *shash = crypto_shash_alg(tfm);
67 unsigned long alignmask = crypto_shash_alignmask(tfm);
68 int err;
69
70 if ((unsigned long)key & alignmask)
71 err = shash_setkey_unaligned(tfm, key, keylen);
72 else
73 err = shash->setkey(tfm, key, keylen);
74
75 if (unlikely(err)) {
76 shash_set_needkey(tfm, shash);
77 return err;
78 }
79
80 crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
81 return 0;
82}
83EXPORT_SYMBOL_GPL(crypto_shash_setkey);
84
85static int shash_update_unaligned(struct shash_desc *desc, const u8 *data,
86 unsigned int len)
87{
88 struct crypto_shash *tfm = desc->tfm;
89 struct shash_alg *shash = crypto_shash_alg(tfm);
90 unsigned long alignmask = crypto_shash_alignmask(tfm);
91 unsigned int unaligned_len = alignmask + 1 -
92 ((unsigned long)data & alignmask);
93 /*
94 * We cannot count on __aligned() working for large values:
95 * https://patchwork.kernel.org/patch/9507697/
96 */
97 u8 ubuf[MAX_ALGAPI_ALIGNMASK * 2];
98 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
99 int err;
100
101 if (WARN_ON(buf + unaligned_len > ubuf + sizeof(ubuf)))
102 return -EINVAL;
103
104 if (unaligned_len > len)
105 unaligned_len = len;
106
107 memcpy(buf, data, unaligned_len);
108 err = shash->update(desc, buf, unaligned_len);
109 memset(buf, 0, unaligned_len);
110
111 return err ?:
112 shash->update(desc, data + unaligned_len, len - unaligned_len);
113}
114
115int crypto_shash_update(struct shash_desc *desc, const u8 *data,
116 unsigned int len)
117{
118 struct crypto_shash *tfm = desc->tfm;
119 struct shash_alg *shash = crypto_shash_alg(tfm);
120 unsigned long alignmask = crypto_shash_alignmask(tfm);
121
122 if ((unsigned long)data & alignmask)
123 return shash_update_unaligned(desc, data, len);
124
125 return shash->update(desc, data, len);
126}
127EXPORT_SYMBOL_GPL(crypto_shash_update);
128
129static int shash_final_unaligned(struct shash_desc *desc, u8 *out)
130{
131 struct crypto_shash *tfm = desc->tfm;
132 unsigned long alignmask = crypto_shash_alignmask(tfm);
133 struct shash_alg *shash = crypto_shash_alg(tfm);
134 unsigned int ds = crypto_shash_digestsize(tfm);
135 /*
136 * We cannot count on __aligned() working for large values:
137 * https://patchwork.kernel.org/patch/9507697/
138 */
139 u8 ubuf[MAX_ALGAPI_ALIGNMASK + HASH_MAX_DIGESTSIZE];
140 u8 *buf = PTR_ALIGN(&ubuf[0], alignmask + 1);
141 int err;
142
143 if (WARN_ON(buf + ds > ubuf + sizeof(ubuf)))
144 return -EINVAL;
145
146 err = shash->final(desc, buf);
147 if (err)
148 goto out;
149
150 memcpy(out, buf, ds);
151
152out:
153 memset(buf, 0, ds);
154 return err;
155}
156
157int crypto_shash_final(struct shash_desc *desc, u8 *out)
158{
159 struct crypto_shash *tfm = desc->tfm;
160 struct shash_alg *shash = crypto_shash_alg(tfm);
161 unsigned long alignmask = crypto_shash_alignmask(tfm);
162
163 if ((unsigned long)out & alignmask)
164 return shash_final_unaligned(desc, out);
165
166 return shash->final(desc, out);
167}
168EXPORT_SYMBOL_GPL(crypto_shash_final);
169
170static int shash_finup_unaligned(struct shash_desc *desc, const u8 *data,
171 unsigned int len, u8 *out)
172{
173 return crypto_shash_update(desc, data, len) ?:
174 crypto_shash_final(desc, out);
175}
176
177int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
178 unsigned int len, u8 *out)
179{
180 struct crypto_shash *tfm = desc->tfm;
181 struct shash_alg *shash = crypto_shash_alg(tfm);
182 unsigned long alignmask = crypto_shash_alignmask(tfm);
183
184 if (((unsigned long)data | (unsigned long)out) & alignmask)
185 return shash_finup_unaligned(desc, data, len, out);
186
187 return shash->finup(desc, data, len, out);
188}
189EXPORT_SYMBOL_GPL(crypto_shash_finup);
190
191static int shash_digest_unaligned(struct shash_desc *desc, const u8 *data,
192 unsigned int len, u8 *out)
193{
194 return crypto_shash_init(desc) ?:
195 crypto_shash_finup(desc, data, len, out);
196}
197
198int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
199 unsigned int len, u8 *out)
200{
201 struct crypto_shash *tfm = desc->tfm;
202 struct shash_alg *shash = crypto_shash_alg(tfm);
203 unsigned long alignmask = crypto_shash_alignmask(tfm);
204
205 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
206 return -ENOKEY;
207
208 if (((unsigned long)data | (unsigned long)out) & alignmask)
209 return shash_digest_unaligned(desc, data, len, out);
210
211 return shash->digest(desc, data, len, out);
212}
213EXPORT_SYMBOL_GPL(crypto_shash_digest);
214
215static int shash_default_export(struct shash_desc *desc, void *out)
216{
217 memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(desc->tfm));
218 return 0;
219}
220
221static int shash_default_import(struct shash_desc *desc, const void *in)
222{
223 memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(desc->tfm));
224 return 0;
225}
226
227static int shash_async_setkey(struct crypto_ahash *tfm, const u8 *key,
228 unsigned int keylen)
229{
230 struct crypto_shash **ctx = crypto_ahash_ctx(tfm);
231
232 return crypto_shash_setkey(*ctx, key, keylen);
233}
234
235static int shash_async_init(struct ahash_request *req)
236{
237 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
238 struct shash_desc *desc = ahash_request_ctx(req);
239
240 desc->tfm = *ctx;
241 desc->flags = req->base.flags;
242
243 return crypto_shash_init(desc);
244}
245
246int shash_ahash_update(struct ahash_request *req, struct shash_desc *desc)
247{
248 struct crypto_hash_walk walk;
249 int nbytes;
250
251 for (nbytes = crypto_hash_walk_first(req, &walk); nbytes > 0;
252 nbytes = crypto_hash_walk_done(&walk, nbytes))
253 nbytes = crypto_shash_update(desc, walk.data, nbytes);
254
255 return nbytes;
256}
257EXPORT_SYMBOL_GPL(shash_ahash_update);
258
259static int shash_async_update(struct ahash_request *req)
260{
261 return shash_ahash_update(req, ahash_request_ctx(req));
262}
263
264static int shash_async_final(struct ahash_request *req)
265{
266 return crypto_shash_final(ahash_request_ctx(req), req->result);
267}
268
269int shash_ahash_finup(struct ahash_request *req, struct shash_desc *desc)
270{
271 struct crypto_hash_walk walk;
272 int nbytes;
273
274 nbytes = crypto_hash_walk_first(req, &walk);
275 if (!nbytes)
276 return crypto_shash_final(desc, req->result);
277
278 do {
279 nbytes = crypto_hash_walk_last(&walk) ?
280 crypto_shash_finup(desc, walk.data, nbytes,
281 req->result) :
282 crypto_shash_update(desc, walk.data, nbytes);
283 nbytes = crypto_hash_walk_done(&walk, nbytes);
284 } while (nbytes > 0);
285
286 return nbytes;
287}
288EXPORT_SYMBOL_GPL(shash_ahash_finup);
289
290static int shash_async_finup(struct ahash_request *req)
291{
292 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
293 struct shash_desc *desc = ahash_request_ctx(req);
294
295 desc->tfm = *ctx;
296 desc->flags = req->base.flags;
297
298 return shash_ahash_finup(req, desc);
299}
300
301int shash_ahash_digest(struct ahash_request *req, struct shash_desc *desc)
302{
303 unsigned int nbytes = req->nbytes;
304 struct scatterlist *sg;
305 unsigned int offset;
306 int err;
307
308 if (nbytes &&
309 (sg = req->src, offset = sg->offset,
310 nbytes < min(sg->length, ((unsigned int)(PAGE_SIZE)) - offset))) {
311 void *data;
312
313 data = kmap_atomic(sg_page(sg));
314 err = crypto_shash_digest(desc, data + offset, nbytes,
315 req->result);
316 kunmap_atomic(data);
317 crypto_yield(desc->flags);
318 } else
319 err = crypto_shash_init(desc) ?:
320 shash_ahash_finup(req, desc);
321
322 return err;
323}
324EXPORT_SYMBOL_GPL(shash_ahash_digest);
325
326static int shash_async_digest(struct ahash_request *req)
327{
328 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
329 struct shash_desc *desc = ahash_request_ctx(req);
330
331 desc->tfm = *ctx;
332 desc->flags = req->base.flags;
333
334 return shash_ahash_digest(req, desc);
335}
336
337static int shash_async_export(struct ahash_request *req, void *out)
338{
339 return crypto_shash_export(ahash_request_ctx(req), out);
340}
341
342static int shash_async_import(struct ahash_request *req, const void *in)
343{
344 struct crypto_shash **ctx = crypto_ahash_ctx(crypto_ahash_reqtfm(req));
345 struct shash_desc *desc = ahash_request_ctx(req);
346
347 desc->tfm = *ctx;
348 desc->flags = req->base.flags;
349
350 return crypto_shash_import(desc, in);
351}
352
353static void crypto_exit_shash_ops_async(struct crypto_tfm *tfm)
354{
355 struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
356
357 crypto_free_shash(*ctx);
358}
359
360int crypto_init_shash_ops_async(struct crypto_tfm *tfm)
361{
362 struct crypto_alg *calg = tfm->__crt_alg;
363 struct shash_alg *alg = __crypto_shash_alg(calg);
364 struct crypto_ahash *crt = __crypto_ahash_cast(tfm);
365 struct crypto_shash **ctx = crypto_tfm_ctx(tfm);
366 struct crypto_shash *shash;
367
368 if (!crypto_mod_get(calg))
369 return -EAGAIN;
370
371 shash = crypto_create_tfm(calg, &crypto_shash_type);
372 if (IS_ERR(shash)) {
373 crypto_mod_put(calg);
374 return PTR_ERR(shash);
375 }
376
377 *ctx = shash;
378 tfm->exit = crypto_exit_shash_ops_async;
379
380 crt->init = shash_async_init;
381 crt->update = shash_async_update;
382 crt->final = shash_async_final;
383 crt->finup = shash_async_finup;
384 crt->digest = shash_async_digest;
385 if (crypto_shash_alg_has_setkey(alg))
386 crt->setkey = shash_async_setkey;
387
388 crypto_ahash_set_flags(crt, crypto_shash_get_flags(shash) &
389 CRYPTO_TFM_NEED_KEY);
390
391 crt->export = shash_async_export;
392 crt->import = shash_async_import;
393
394 crt->reqsize = sizeof(struct shash_desc) + crypto_shash_descsize(shash);
395
396 return 0;
397}
398
399static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
400{
401 struct crypto_shash *hash = __crypto_shash_cast(tfm);
402 struct shash_alg *alg = crypto_shash_alg(hash);
403
404 hash->descsize = alg->descsize;
405
406 shash_set_needkey(hash, alg);
407
408 return 0;
409}
410
411#ifdef CONFIG_NET
412static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
413{
414 struct crypto_report_hash rhash;
415 struct shash_alg *salg = __crypto_shash_alg(alg);
416
417 memset(&rhash, 0, sizeof(rhash));
418
419 strscpy(rhash.type, "shash", sizeof(rhash.type));
420
421 rhash.blocksize = alg->cra_blocksize;
422 rhash.digestsize = salg->digestsize;
423
424 return nla_put(skb, CRYPTOCFGA_REPORT_HASH, sizeof(rhash), &rhash);
425}
426#else
427static int crypto_shash_report(struct sk_buff *skb, struct crypto_alg *alg)
428{
429 return -ENOSYS;
430}
431#endif
432
433static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
434 __maybe_unused;
435static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
436{
437 struct shash_alg *salg = __crypto_shash_alg(alg);
438
439 seq_printf(m, "type : shash\n");
440 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
441 seq_printf(m, "digestsize : %u\n", salg->digestsize);
442}
443
444static const struct crypto_type crypto_shash_type = {
445 .extsize = crypto_alg_extsize,
446 .init_tfm = crypto_shash_init_tfm,
447#ifdef CONFIG_PROC_FS
448 .show = crypto_shash_show,
449#endif
450 .report = crypto_shash_report,
451 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
452 .maskset = CRYPTO_ALG_TYPE_MASK,
453 .type = CRYPTO_ALG_TYPE_SHASH,
454 .tfmsize = offsetof(struct crypto_shash, base),
455};
456
457struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
458 u32 mask)
459{
460 return crypto_alloc_tfm(alg_name, &crypto_shash_type, type, mask);
461}
462EXPORT_SYMBOL_GPL(crypto_alloc_shash);
463
464static int shash_prepare_alg(struct shash_alg *alg)
465{
466 struct crypto_alg *base = &alg->base;
467
468 if (alg->digestsize > HASH_MAX_DIGESTSIZE ||
469 alg->descsize > HASH_MAX_DESCSIZE ||
470 alg->statesize > HASH_MAX_STATESIZE)
471 return -EINVAL;
472
473 if ((alg->export && !alg->import) || (alg->import && !alg->export))
474 return -EINVAL;
475
476 base->cra_type = &crypto_shash_type;
477 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
478 base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
479
480 if (!alg->finup)
481 alg->finup = shash_finup_unaligned;
482 if (!alg->digest)
483 alg->digest = shash_digest_unaligned;
484 if (!alg->export) {
485 alg->export = shash_default_export;
486 alg->import = shash_default_import;
487 alg->statesize = alg->descsize;
488 }
489 if (!alg->setkey)
490 alg->setkey = shash_no_setkey;
491
492 return 0;
493}
494
495int crypto_register_shash(struct shash_alg *alg)
496{
497 struct crypto_alg *base = &alg->base;
498 int err;
499
500 err = shash_prepare_alg(alg);
501 if (err)
502 return err;
503
504 return crypto_register_alg(base);
505}
506EXPORT_SYMBOL_GPL(crypto_register_shash);
507
508int crypto_unregister_shash(struct shash_alg *alg)
509{
510 return crypto_unregister_alg(&alg->base);
511}
512EXPORT_SYMBOL_GPL(crypto_unregister_shash);
513
514int crypto_register_shashes(struct shash_alg *algs, int count)
515{
516 int i, ret;
517
518 for (i = 0; i < count; i++) {
519 ret = crypto_register_shash(&algs[i]);
520 if (ret)
521 goto err;
522 }
523
524 return 0;
525
526err:
527 for (--i; i >= 0; --i)
528 crypto_unregister_shash(&algs[i]);
529
530 return ret;
531}
532EXPORT_SYMBOL_GPL(crypto_register_shashes);
533
534int crypto_unregister_shashes(struct shash_alg *algs, int count)
535{
536 int i, ret;
537
538 for (i = count - 1; i >= 0; --i) {
539 ret = crypto_unregister_shash(&algs[i]);
540 if (ret)
541 pr_err("Failed to unregister %s %s: %d\n",
542 algs[i].base.cra_driver_name,
543 algs[i].base.cra_name, ret);
544 }
545
546 return 0;
547}
548EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
549
550int shash_register_instance(struct crypto_template *tmpl,
551 struct shash_instance *inst)
552{
553 int err;
554
555 err = shash_prepare_alg(&inst->alg);
556 if (err)
557 return err;
558
559 return crypto_register_instance(tmpl, shash_crypto_instance(inst));
560}
561EXPORT_SYMBOL_GPL(shash_register_instance);
562
563void shash_free_instance(struct crypto_instance *inst)
564{
565 crypto_drop_spawn(crypto_instance_ctx(inst));
566 kfree(shash_instance(inst));
567}
568EXPORT_SYMBOL_GPL(shash_free_instance);
569
570int crypto_init_shash_spawn(struct crypto_shash_spawn *spawn,
571 struct shash_alg *alg,
572 struct crypto_instance *inst)
573{
574 return crypto_init_spawn2(&spawn->base, &alg->base, inst,
575 &crypto_shash_type);
576}
577EXPORT_SYMBOL_GPL(crypto_init_shash_spawn);
578
579struct shash_alg *shash_attr_alg(struct rtattr *rta, u32 type, u32 mask)
580{
581 struct crypto_alg *alg;
582
583 alg = crypto_attr_alg2(rta, &crypto_shash_type, type, mask);
584 return IS_ERR(alg) ? ERR_CAST(alg) :
585 container_of(alg, struct shash_alg, base);
586}
587EXPORT_SYMBOL_GPL(shash_attr_alg);
588
589MODULE_LICENSE("GPL");
590MODULE_DESCRIPTION("Synchronous cryptographic hash type");
591