1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Synchronous Cryptographic Hash operations.
4 *
5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
6 */
7
8#include <crypto/scatterwalk.h>
9#include <linux/cryptouser.h>
10#include <linux/err.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/seq_file.h>
14#include <linux/string.h>
15#include <net/netlink.h>
16
17#include "hash.h"
18
19static inline struct crypto_istat_hash *shash_get_stat(struct shash_alg *alg)
20{
21 return hash_get_stat(alg: &alg->halg);
22}
23
24static inline int crypto_shash_errstat(struct shash_alg *alg, int err)
25{
26 if (IS_ENABLED(CONFIG_CRYPTO_STATS) && err)
27 atomic64_inc(v: &shash_get_stat(alg)->err_cnt);
28 return err;
29}
30
31int shash_no_setkey(struct crypto_shash *tfm, const u8 *key,
32 unsigned int keylen)
33{
34 return -ENOSYS;
35}
36EXPORT_SYMBOL_GPL(shash_no_setkey);
37
38static void shash_set_needkey(struct crypto_shash *tfm, struct shash_alg *alg)
39{
40 if (crypto_shash_alg_needs_key(alg))
41 crypto_shash_set_flags(tfm, CRYPTO_TFM_NEED_KEY);
42}
43
44int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
45 unsigned int keylen)
46{
47 struct shash_alg *shash = crypto_shash_alg(tfm);
48 int err;
49
50 err = shash->setkey(tfm, key, keylen);
51 if (unlikely(err)) {
52 shash_set_needkey(tfm, alg: shash);
53 return err;
54 }
55
56 crypto_shash_clear_flags(tfm, CRYPTO_TFM_NEED_KEY);
57 return 0;
58}
59EXPORT_SYMBOL_GPL(crypto_shash_setkey);
60
61int crypto_shash_update(struct shash_desc *desc, const u8 *data,
62 unsigned int len)
63{
64 struct shash_alg *shash = crypto_shash_alg(tfm: desc->tfm);
65 int err;
66
67 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
68 atomic64_add(i: len, v: &shash_get_stat(alg: shash)->hash_tlen);
69
70 err = shash->update(desc, data, len);
71
72 return crypto_shash_errstat(alg: shash, err);
73}
74EXPORT_SYMBOL_GPL(crypto_shash_update);
75
76int crypto_shash_final(struct shash_desc *desc, u8 *out)
77{
78 struct shash_alg *shash = crypto_shash_alg(tfm: desc->tfm);
79 int err;
80
81 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
82 atomic64_inc(v: &shash_get_stat(alg: shash)->hash_cnt);
83
84 err = shash->final(desc, out);
85
86 return crypto_shash_errstat(alg: shash, err);
87}
88EXPORT_SYMBOL_GPL(crypto_shash_final);
89
90static int shash_default_finup(struct shash_desc *desc, const u8 *data,
91 unsigned int len, u8 *out)
92{
93 struct shash_alg *shash = crypto_shash_alg(tfm: desc->tfm);
94
95 return shash->update(desc, data, len) ?:
96 shash->final(desc, out);
97}
98
99int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
100 unsigned int len, u8 *out)
101{
102 struct crypto_shash *tfm = desc->tfm;
103 struct shash_alg *shash = crypto_shash_alg(tfm);
104 int err;
105
106 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
107 struct crypto_istat_hash *istat = shash_get_stat(alg: shash);
108
109 atomic64_inc(v: &istat->hash_cnt);
110 atomic64_add(i: len, v: &istat->hash_tlen);
111 }
112
113 err = shash->finup(desc, data, len, out);
114
115 return crypto_shash_errstat(alg: shash, err);
116}
117EXPORT_SYMBOL_GPL(crypto_shash_finup);
118
119static int shash_default_digest(struct shash_desc *desc, const u8 *data,
120 unsigned int len, u8 *out)
121{
122 struct shash_alg *shash = crypto_shash_alg(tfm: desc->tfm);
123
124 return shash->init(desc) ?:
125 shash->finup(desc, data, len, out);
126}
127
128int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
129 unsigned int len, u8 *out)
130{
131 struct crypto_shash *tfm = desc->tfm;
132 struct shash_alg *shash = crypto_shash_alg(tfm);
133 int err;
134
135 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) {
136 struct crypto_istat_hash *istat = shash_get_stat(alg: shash);
137
138 atomic64_inc(v: &istat->hash_cnt);
139 atomic64_add(i: len, v: &istat->hash_tlen);
140 }
141
142 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
143 err = -ENOKEY;
144 else
145 err = shash->digest(desc, data, len, out);
146
147 return crypto_shash_errstat(alg: shash, err);
148}
149EXPORT_SYMBOL_GPL(crypto_shash_digest);
150
151int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
152 unsigned int len, u8 *out)
153{
154 SHASH_DESC_ON_STACK(desc, tfm);
155 int err;
156
157 desc->tfm = tfm;
158
159 err = crypto_shash_digest(desc, data, len, out);
160
161 shash_desc_zero(desc);
162
163 return err;
164}
165EXPORT_SYMBOL_GPL(crypto_shash_tfm_digest);
166
167int crypto_shash_export(struct shash_desc *desc, void *out)
168{
169 struct crypto_shash *tfm = desc->tfm;
170 struct shash_alg *shash = crypto_shash_alg(tfm);
171
172 if (shash->export)
173 return shash->export(desc, out);
174
175 memcpy(out, shash_desc_ctx(desc), crypto_shash_descsize(tfm));
176 return 0;
177}
178EXPORT_SYMBOL_GPL(crypto_shash_export);
179
180int crypto_shash_import(struct shash_desc *desc, const void *in)
181{
182 struct crypto_shash *tfm = desc->tfm;
183 struct shash_alg *shash = crypto_shash_alg(tfm);
184
185 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
186 return -ENOKEY;
187
188 if (shash->import)
189 return shash->import(desc, in);
190
191 memcpy(shash_desc_ctx(desc), in, crypto_shash_descsize(tfm));
192 return 0;
193}
194EXPORT_SYMBOL_GPL(crypto_shash_import);
195
196static void crypto_shash_exit_tfm(struct crypto_tfm *tfm)
197{
198 struct crypto_shash *hash = __crypto_shash_cast(tfm);
199 struct shash_alg *alg = crypto_shash_alg(tfm: hash);
200
201 alg->exit_tfm(hash);
202}
203
204static int crypto_shash_init_tfm(struct crypto_tfm *tfm)
205{
206 struct crypto_shash *hash = __crypto_shash_cast(tfm);
207 struct shash_alg *alg = crypto_shash_alg(tfm: hash);
208 int err;
209
210 hash->descsize = alg->descsize;
211
212 shash_set_needkey(tfm: hash, alg);
213
214 if (alg->exit_tfm)
215 tfm->exit = crypto_shash_exit_tfm;
216
217 if (!alg->init_tfm)
218 return 0;
219
220 err = alg->init_tfm(hash);
221 if (err)
222 return err;
223
224 /* ->init_tfm() may have increased the descsize. */
225 if (WARN_ON_ONCE(hash->descsize > HASH_MAX_DESCSIZE)) {
226 if (alg->exit_tfm)
227 alg->exit_tfm(hash);
228 return -EINVAL;
229 }
230
231 return 0;
232}
233
234static void crypto_shash_free_instance(struct crypto_instance *inst)
235{
236 struct shash_instance *shash = shash_instance(inst);
237
238 shash->free(shash);
239}
240
241static int __maybe_unused crypto_shash_report(
242 struct sk_buff *skb, struct crypto_alg *alg)
243{
244 struct crypto_report_hash rhash;
245 struct shash_alg *salg = __crypto_shash_alg(alg);
246
247 memset(&rhash, 0, sizeof(rhash));
248
249 strscpy(rhash.type, "shash", sizeof(rhash.type));
250
251 rhash.blocksize = alg->cra_blocksize;
252 rhash.digestsize = salg->digestsize;
253
254 return nla_put(skb, attrtype: CRYPTOCFGA_REPORT_HASH, attrlen: sizeof(rhash), data: &rhash);
255}
256
257static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
258 __maybe_unused;
259static void crypto_shash_show(struct seq_file *m, struct crypto_alg *alg)
260{
261 struct shash_alg *salg = __crypto_shash_alg(alg);
262
263 seq_printf(m, fmt: "type : shash\n");
264 seq_printf(m, fmt: "blocksize : %u\n", alg->cra_blocksize);
265 seq_printf(m, fmt: "digestsize : %u\n", salg->digestsize);
266}
267
268static int __maybe_unused crypto_shash_report_stat(
269 struct sk_buff *skb, struct crypto_alg *alg)
270{
271 return crypto_hash_report_stat(skb, alg, type: "shash");
272}
273
274const struct crypto_type crypto_shash_type = {
275 .extsize = crypto_alg_extsize,
276 .init_tfm = crypto_shash_init_tfm,
277 .free = crypto_shash_free_instance,
278#ifdef CONFIG_PROC_FS
279 .show = crypto_shash_show,
280#endif
281#if IS_ENABLED(CONFIG_CRYPTO_USER)
282 .report = crypto_shash_report,
283#endif
284#ifdef CONFIG_CRYPTO_STATS
285 .report_stat = crypto_shash_report_stat,
286#endif
287 .maskclear = ~CRYPTO_ALG_TYPE_MASK,
288 .maskset = CRYPTO_ALG_TYPE_MASK,
289 .type = CRYPTO_ALG_TYPE_SHASH,
290 .tfmsize = offsetof(struct crypto_shash, base),
291};
292
293int crypto_grab_shash(struct crypto_shash_spawn *spawn,
294 struct crypto_instance *inst,
295 const char *name, u32 type, u32 mask)
296{
297 spawn->base.frontend = &crypto_shash_type;
298 return crypto_grab_spawn(spawn: &spawn->base, inst, name, type, mask);
299}
300EXPORT_SYMBOL_GPL(crypto_grab_shash);
301
302struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
303 u32 mask)
304{
305 return crypto_alloc_tfm(alg_name, frontend: &crypto_shash_type, type, mask);
306}
307EXPORT_SYMBOL_GPL(crypto_alloc_shash);
308
309int crypto_has_shash(const char *alg_name, u32 type, u32 mask)
310{
311 return crypto_type_has_alg(name: alg_name, frontend: &crypto_shash_type, type, mask);
312}
313EXPORT_SYMBOL_GPL(crypto_has_shash);
314
315struct crypto_shash *crypto_clone_shash(struct crypto_shash *hash)
316{
317 struct crypto_tfm *tfm = crypto_shash_tfm(tfm: hash);
318 struct shash_alg *alg = crypto_shash_alg(tfm: hash);
319 struct crypto_shash *nhash;
320 int err;
321
322 if (!crypto_shash_alg_has_setkey(alg)) {
323 tfm = crypto_tfm_get(tfm);
324 if (IS_ERR(ptr: tfm))
325 return ERR_CAST(ptr: tfm);
326
327 return hash;
328 }
329
330 if (!alg->clone_tfm && (alg->init_tfm || alg->base.cra_init))
331 return ERR_PTR(error: -ENOSYS);
332
333 nhash = crypto_clone_tfm(frontend: &crypto_shash_type, otfm: tfm);
334 if (IS_ERR(ptr: nhash))
335 return nhash;
336
337 nhash->descsize = hash->descsize;
338
339 if (alg->clone_tfm) {
340 err = alg->clone_tfm(nhash, hash);
341 if (err) {
342 crypto_free_shash(tfm: nhash);
343 return ERR_PTR(error: err);
344 }
345 }
346
347 return nhash;
348}
349EXPORT_SYMBOL_GPL(crypto_clone_shash);
350
351int hash_prepare_alg(struct hash_alg_common *alg)
352{
353 struct crypto_istat_hash *istat = hash_get_stat(alg);
354 struct crypto_alg *base = &alg->base;
355
356 if (alg->digestsize > HASH_MAX_DIGESTSIZE)
357 return -EINVAL;
358
359 /* alignmask is not useful for hashes, so it is not supported. */
360 if (base->cra_alignmask)
361 return -EINVAL;
362
363 base->cra_flags &= ~CRYPTO_ALG_TYPE_MASK;
364
365 if (IS_ENABLED(CONFIG_CRYPTO_STATS))
366 memset(istat, 0, sizeof(*istat));
367
368 return 0;
369}
370
371static int shash_prepare_alg(struct shash_alg *alg)
372{
373 struct crypto_alg *base = &alg->halg.base;
374 int err;
375
376 if (alg->descsize > HASH_MAX_DESCSIZE)
377 return -EINVAL;
378
379 if ((alg->export && !alg->import) || (alg->import && !alg->export))
380 return -EINVAL;
381
382 err = hash_prepare_alg(alg: &alg->halg);
383 if (err)
384 return err;
385
386 base->cra_type = &crypto_shash_type;
387 base->cra_flags |= CRYPTO_ALG_TYPE_SHASH;
388
389 /*
390 * Handle missing optional functions. For each one we can either
391 * install a default here, or we can leave the pointer as NULL and check
392 * the pointer for NULL in crypto_shash_*(), avoiding an indirect call
393 * when the default behavior is desired. For ->finup and ->digest we
394 * install defaults, since for optimal performance algorithms should
395 * implement these anyway. On the other hand, for ->import and
396 * ->export the common case and best performance comes from the simple
397 * memcpy of the shash_desc_ctx, so when those pointers are NULL we
398 * leave them NULL and provide the memcpy with no indirect call.
399 */
400 if (!alg->finup)
401 alg->finup = shash_default_finup;
402 if (!alg->digest)
403 alg->digest = shash_default_digest;
404 if (!alg->export)
405 alg->halg.statesize = alg->descsize;
406 if (!alg->setkey)
407 alg->setkey = shash_no_setkey;
408
409 return 0;
410}
411
412int crypto_register_shash(struct shash_alg *alg)
413{
414 struct crypto_alg *base = &alg->base;
415 int err;
416
417 err = shash_prepare_alg(alg);
418 if (err)
419 return err;
420
421 return crypto_register_alg(alg: base);
422}
423EXPORT_SYMBOL_GPL(crypto_register_shash);
424
425void crypto_unregister_shash(struct shash_alg *alg)
426{
427 crypto_unregister_alg(alg: &alg->base);
428}
429EXPORT_SYMBOL_GPL(crypto_unregister_shash);
430
431int crypto_register_shashes(struct shash_alg *algs, int count)
432{
433 int i, ret;
434
435 for (i = 0; i < count; i++) {
436 ret = crypto_register_shash(&algs[i]);
437 if (ret)
438 goto err;
439 }
440
441 return 0;
442
443err:
444 for (--i; i >= 0; --i)
445 crypto_unregister_shash(&algs[i]);
446
447 return ret;
448}
449EXPORT_SYMBOL_GPL(crypto_register_shashes);
450
451void crypto_unregister_shashes(struct shash_alg *algs, int count)
452{
453 int i;
454
455 for (i = count - 1; i >= 0; --i)
456 crypto_unregister_shash(&algs[i]);
457}
458EXPORT_SYMBOL_GPL(crypto_unregister_shashes);
459
460int shash_register_instance(struct crypto_template *tmpl,
461 struct shash_instance *inst)
462{
463 int err;
464
465 if (WARN_ON(!inst->free))
466 return -EINVAL;
467
468 err = shash_prepare_alg(alg: &inst->alg);
469 if (err)
470 return err;
471
472 return crypto_register_instance(tmpl, inst: shash_crypto_instance(inst));
473}
474EXPORT_SYMBOL_GPL(shash_register_instance);
475
476void shash_free_singlespawn_instance(struct shash_instance *inst)
477{
478 crypto_drop_spawn(spawn: shash_instance_ctx(inst));
479 kfree(objp: inst);
480}
481EXPORT_SYMBOL_GPL(shash_free_singlespawn_instance);
482
483MODULE_LICENSE("GPL");
484MODULE_DESCRIPTION("Synchronous cryptographic hash type");
485

source code of linux/crypto/shash.c