1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3 * Hash: Hash algorithms under the crypto API
4 *
5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
6 */
7
8 #ifndef _CRYPTO_HASH_H
9 #define _CRYPTO_HASH_H
10
11 #include <linux/atomic.h>
12 #include <linux/crypto.h>
13 #include <linux/string.h>
14
15 struct crypto_ahash;
16
17 /**
18 * DOC: Message Digest Algorithm Definitions
19 *
20 * These data structures define modular message digest algorithm
21 * implementations, managed via crypto_register_ahash(),
22 * crypto_register_shash(), crypto_unregister_ahash() and
23 * crypto_unregister_shash().
24 */
25
26 /*
27 * struct hash_alg_common - define properties of message digest
28 * @digestsize: Size of the result of the transformation. A buffer of this size
29 * must be available to the @final and @finup calls, so they can
30 * store the resulting hash into it. For various predefined sizes,
31 * search include/crypto/ using
32 * git grep _DIGEST_SIZE include/crypto.
33 * @statesize: Size of the block for partial state of the transformation. A
34 * buffer of this size must be passed to the @export function as it
35 * will save the partial state of the transformation into it. On the
36 * other side, the @import function will load the state from a
37 * buffer of this size as well.
38 * @base: Start of data structure of cipher algorithm. The common data
39 * structure of crypto_alg contains information common to all ciphers.
40 * The hash_alg_common data structure now adds the hash-specific
41 * information.
42 */
43 #define HASH_ALG_COMMON { \
44 unsigned int digestsize; \
45 unsigned int statesize; \
46 \
47 struct crypto_alg base; \
48 }
49 struct hash_alg_common HASH_ALG_COMMON;
50
51 struct ahash_request {
52 struct crypto_async_request base;
53
54 unsigned int nbytes;
55 struct scatterlist *src;
56 u8 *result;
57
58 /* This field may only be used by the ahash API code. */
59 void *priv;
60
61 void *__ctx[] CRYPTO_MINALIGN_ATTR;
62 };
63
64 /**
65 * struct ahash_alg - asynchronous message digest definition
66 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the
67 * state of the HASH transformation at the beginning. This shall fill in
68 * the internal structures used during the entire duration of the whole
69 * transformation. No data processing happens at this point. Driver code
70 * implementation must not use req->result.
71 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
72 * function actually pushes blocks of data from upper layers into the
73 * driver, which then passes those to the hardware as seen fit. This
74 * function must not finalize the HASH transformation by calculating the
75 * final message digest as this only adds more data into the
76 * transformation. This function shall not modify the transformation
77 * context, as this function may be called in parallel with the same
78 * transformation object. Data processing can happen synchronously
79 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use
80 * req->result.
81 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
82 * transformation and retrieves the resulting hash from the driver and
83 * pushes it back to upper layers. No data processing happens at this
84 * point unless hardware requires it to finish the transformation
85 * (then the data buffered by the device driver is processed).
86 * @finup: **[optional]** Combination of @update and @final. This function is effectively a
87 * combination of @update and @final calls issued in sequence. As some
88 * hardware cannot do @update and @final separately, this callback was
89 * added to allow such hardware to be used at least by IPsec. Data
90 * processing can happen synchronously [SHASH] or asynchronously [AHASH]
91 * at this point.
92 * @digest: Combination of @init and @update and @final. This function
93 * effectively behaves as the entire chain of operations, @init,
94 * @update and @final issued in sequence. Just like @finup, this was
95 * added for hardware which cannot do even the @finup, but can only do
96 * the whole transformation in one run. Data processing can happen
97 * synchronously [SHASH] or asynchronously [AHASH] at this point.
98 * @setkey: Set optional key used by the hashing algorithm. Intended to push
99 * optional key used by the hashing algorithm from upper layers into
100 * the driver. This function can store the key in the transformation
101 * context or can outright program it into the hardware. In the former
102 * case, one must be careful to program the key into the hardware at
103 * appropriate time and one must be careful that .setkey() can be
104 * called multiple times during the existence of the transformation
105 * object. Not all hashing algorithms do implement this function as it
106 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
107 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
108 * this function. This function must be called before any other of the
109 * @init, @update, @final, @finup, @digest is called. No data
110 * processing happens at this point.
111 * @export: Export partial state of the transformation. This function dumps the
112 * entire state of the ongoing transformation into a provided block of
113 * data so it can be @import 'ed back later on. This is useful in case
114 * you want to save partial result of the transformation after
115 * processing certain amount of data and reload this partial result
116 * multiple times later on for multiple re-use. No data processing
117 * happens at this point. Driver must not use req->result.
118 * @import: Import partial state of the transformation. This function loads the
119 * entire state of the ongoing transformation from a provided block of
120 * data so the transformation can continue from this point onward. No
121 * data processing happens at this point. Driver must not use
122 * req->result.
123 * @init_tfm: Initialize the cryptographic transformation object.
124 * This function is called only once at the instantiation
125 * time, right after the transformation context was
126 * allocated. In case the cryptographic hardware has
127 * some special requirements which need to be handled
128 * by software, this function shall check for the precise
129 * requirement of the transformation and put any software
130 * fallbacks in place.
131 * @exit_tfm: Deinitialize the cryptographic transformation object.
132 * This is a counterpart to @init_tfm, used to remove
133 * various changes set in @init_tfm.
134 * @clone_tfm: Copy transform into new object, may allocate memory.
135 * @halg: see struct hash_alg_common
136 */
137 struct ahash_alg {
138 int (*init)(struct ahash_request *req);
139 int (*update)(struct ahash_request *req);
140 int (*final)(struct ahash_request *req);
141 int (*finup)(struct ahash_request *req);
142 int (*digest)(struct ahash_request *req);
143 int (*export)(struct ahash_request *req, void *out);
144 int (*import)(struct ahash_request *req, const void *in);
145 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
146 unsigned int keylen);
147 int (*init_tfm)(struct crypto_ahash *tfm);
148 void (*exit_tfm)(struct crypto_ahash *tfm);
149 int (*clone_tfm)(struct crypto_ahash *dst, struct crypto_ahash *src);
150
151 struct hash_alg_common halg;
152 };
153
154 struct shash_desc {
155 struct crypto_shash *tfm;
156 void *__ctx[] __aligned(ARCH_SLAB_MINALIGN);
157 };
158
159 #define HASH_MAX_DIGESTSIZE 64
160
161 /*
162 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc'
163 * containing a 'struct sha3_state'.
164 */
165 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360)
166
167 #define SHASH_DESC_ON_STACK(shash, ctx) \
168 char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \
169 __aligned(__alignof__(struct shash_desc)); \
170 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
171
172 /**
173 * struct shash_alg - synchronous message digest definition
174 * @init: see struct ahash_alg
175 * @update: see struct ahash_alg
176 * @final: see struct ahash_alg
177 * @finup: see struct ahash_alg
178 * @digest: see struct ahash_alg
179 * @export: see struct ahash_alg
180 * @import: see struct ahash_alg
181 * @setkey: see struct ahash_alg
182 * @init_tfm: Initialize the cryptographic transformation object.
183 * This function is called only once at the instantiation
184 * time, right after the transformation context was
185 * allocated. In case the cryptographic hardware has
186 * some special requirements which need to be handled
187 * by software, this function shall check for the precise
188 * requirement of the transformation and put any software
189 * fallbacks in place.
190 * @exit_tfm: Deinitialize the cryptographic transformation object.
191 * This is a counterpart to @init_tfm, used to remove
192 * various changes set in @init_tfm.
193 * @clone_tfm: Copy transform into new object, may allocate memory.
194 * @descsize: Size of the operational state for the message digest. This state
195 * size is the memory size that needs to be allocated for
196 * shash_desc.__ctx
197 * @halg: see struct hash_alg_common
198 * @HASH_ALG_COMMON: see struct hash_alg_common
199 */
200 struct shash_alg {
201 int (*init)(struct shash_desc *desc);
202 int (*update)(struct shash_desc *desc, const u8 *data,
203 unsigned int len);
204 int (*final)(struct shash_desc *desc, u8 *out);
205 int (*finup)(struct shash_desc *desc, const u8 *data,
206 unsigned int len, u8 *out);
207 int (*digest)(struct shash_desc *desc, const u8 *data,
208 unsigned int len, u8 *out);
209 int (*export)(struct shash_desc *desc, void *out);
210 int (*import)(struct shash_desc *desc, const void *in);
211 int (*setkey)(struct crypto_shash *tfm, const u8 *key,
212 unsigned int keylen);
213 int (*init_tfm)(struct crypto_shash *tfm);
214 void (*exit_tfm)(struct crypto_shash *tfm);
215 int (*clone_tfm)(struct crypto_shash *dst, struct crypto_shash *src);
216
217 unsigned int descsize;
218
219 union {
220 struct HASH_ALG_COMMON;
221 struct hash_alg_common halg;
222 };
223 };
224 #undef HASH_ALG_COMMON
225
226 struct crypto_ahash {
227 bool using_shash; /* Underlying algorithm is shash, not ahash */
228 unsigned int statesize;
229 unsigned int reqsize;
230 struct crypto_tfm base;
231 };
232
233 struct crypto_shash {
234 unsigned int descsize;
235 struct crypto_tfm base;
236 };
237
238 /**
239 * DOC: Asynchronous Message Digest API
240 *
241 * The asynchronous message digest API is used with the ciphers of type
242 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
243 *
244 * The asynchronous cipher operation discussion provided for the
245 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well.
246 */
247
248 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
249 {
250 return container_of(tfm, struct crypto_ahash, base);
251 }
252
253 /**
254 * crypto_alloc_ahash() - allocate ahash cipher handle
255 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
256 * ahash cipher
257 * @type: specifies the type of the cipher
258 * @mask: specifies the mask for the cipher
259 *
260 * Allocate a cipher handle for an ahash. The returned struct
261 * crypto_ahash is the cipher handle that is required for any subsequent
262 * API invocation for that ahash.
263 *
264 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
265 * of an error, PTR_ERR() returns the error code.
266 */
267 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
268 u32 mask);
269
270 struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *tfm);
271
272 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
273 {
274 return &tfm->base;
275 }
276
277 /**
278 * crypto_free_ahash() - zeroize and free the ahash handle
279 * @tfm: cipher handle to be freed
280 *
281 * If @tfm is a NULL or error pointer, this function does nothing.
282 */
283 static inline void crypto_free_ahash(struct crypto_ahash *tfm)
284 {
285 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
286 }
287
288 /**
289 * crypto_has_ahash() - Search for the availability of an ahash.
290 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
291 * ahash
292 * @type: specifies the type of the ahash
293 * @mask: specifies the mask for the ahash
294 *
295 * Return: true when the ahash is known to the kernel crypto API; false
296 * otherwise
297 */
298 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
299
300 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
301 {
302 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
303 }
304
305 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
306 {
307 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
308 }
309
310 /**
311 * crypto_ahash_blocksize() - obtain block size for cipher
312 * @tfm: cipher handle
313 *
314 * The block size for the message digest cipher referenced with the cipher
315 * handle is returned.
316 *
317 * Return: block size of cipher
318 */
319 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
320 {
321 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
322 }
323
324 static inline struct hash_alg_common *__crypto_hash_alg_common(
325 struct crypto_alg *alg)
326 {
327 return container_of(alg, struct hash_alg_common, base);
328 }
329
330 static inline struct hash_alg_common *crypto_hash_alg_common(
331 struct crypto_ahash *tfm)
332 {
333 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
334 }
335
336 /**
337 * crypto_ahash_digestsize() - obtain message digest size
338 * @tfm: cipher handle
339 *
340 * The size for the message digest created by the message digest cipher
341 * referenced with the cipher handle is returned.
342 *
343 *
344 * Return: message digest size of cipher
345 */
346 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
347 {
348 return crypto_hash_alg_common(tfm)->digestsize;
349 }
350
351 /**
352 * crypto_ahash_statesize() - obtain size of the ahash state
353 * @tfm: cipher handle
354 *
355 * Return the size of the ahash state. With the crypto_ahash_export()
356 * function, the caller can export the state into a buffer whose size is
357 * defined with this function.
358 *
359 * Return: size of the ahash state
360 */
361 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
362 {
363 return tfm->statesize;
364 }
365
366 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
367 {
368 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
369 }
370
371 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
372 {
373 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
374 }
375
376 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
377 {
378 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
379 }
380
381 /**
382 * crypto_ahash_reqtfm() - obtain cipher handle from request
383 * @req: asynchronous request handle that contains the reference to the ahash
384 * cipher handle
385 *
386 * Return the ahash cipher handle that is registered with the asynchronous
387 * request handle ahash_request.
388 *
389 * Return: ahash cipher handle
390 */
391 static inline struct crypto_ahash *crypto_ahash_reqtfm(
392 struct ahash_request *req)
393 {
394 return __crypto_ahash_cast(req->base.tfm);
395 }
396
397 /**
398 * crypto_ahash_reqsize() - obtain size of the request data structure
399 * @tfm: cipher handle
400 *
401 * Return: size of the request data
402 */
403 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
404 {
405 return tfm->reqsize;
406 }
407
408 static inline void *ahash_request_ctx(struct ahash_request *req)
409 {
410 return req->__ctx;
411 }
412
413 /**
414 * crypto_ahash_setkey - set key for cipher handle
415 * @tfm: cipher handle
416 * @key: buffer holding the key
417 * @keylen: length of the key in bytes
418 *
419 * The caller provided key is set for the ahash cipher. The cipher
420 * handle must point to a keyed hash in order for this function to succeed.
421 *
422 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
423 */
424 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
425 unsigned int keylen);
426
427 /**
428 * crypto_ahash_finup() - update and finalize message digest
429 * @req: reference to the ahash_request handle that holds all information
430 * needed to perform the cipher operation
431 *
432 * This function is a "short-hand" for the function calls of
433 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
434 * meaning as discussed for those separate functions.
435 *
436 * Return: see crypto_ahash_final()
437 */
438 int crypto_ahash_finup(struct ahash_request *req);
439
440 /**
441 * crypto_ahash_final() - calculate message digest
442 * @req: reference to the ahash_request handle that holds all information
443 * needed to perform the cipher operation
444 *
445 * Finalize the message digest operation and create the message digest
446 * based on all data added to the cipher handle. The message digest is placed
447 * into the output buffer registered with the ahash_request handle.
448 *
449 * Return:
450 * 0 if the message digest was successfully calculated;
451 * -EINPROGRESS if data is fed into hardware (DMA) or queued for later;
452 * -EBUSY if queue is full and request should be resubmitted later;
453 * other < 0 if an error occurred
454 */
455 int crypto_ahash_final(struct ahash_request *req);
456
457 /**
458 * crypto_ahash_digest() - calculate message digest for a buffer
459 * @req: reference to the ahash_request handle that holds all information
460 * needed to perform the cipher operation
461 *
462 * This function is a "short-hand" for the function calls of crypto_ahash_init,
463 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
464 * meaning as discussed for those separate three functions.
465 *
466 * Return: see crypto_ahash_final()
467 */
468 int crypto_ahash_digest(struct ahash_request *req);
469
470 /**
471 * crypto_ahash_export() - extract current message digest state
472 * @req: reference to the ahash_request handle whose state is exported
473 * @out: output buffer of sufficient size that can hold the hash state
474 *
475 * This function exports the hash state of the ahash_request handle into the
476 * caller-allocated output buffer out which must have sufficient size (e.g. by
477 * calling crypto_ahash_statesize()).
478 *
479 * Return: 0 if the export was successful; < 0 if an error occurred
480 */
481 int crypto_ahash_export(struct ahash_request *req, void *out);
482
483 /**
484 * crypto_ahash_import() - import message digest state
485 * @req: reference to ahash_request handle the state is imported into
486 * @in: buffer holding the state
487 *
488 * This function imports the hash state into the ahash_request handle from the
489 * input buffer. That buffer should have been generated with the
490 * crypto_ahash_export function.
491 *
492 * Return: 0 if the import was successful; < 0 if an error occurred
493 */
494 int crypto_ahash_import(struct ahash_request *req, const void *in);
495
496 /**
497 * crypto_ahash_init() - (re)initialize message digest handle
498 * @req: ahash_request handle that already is initialized with all necessary
499 * data using the ahash_request_* API functions
500 *
501 * The call (re-)initializes the message digest referenced by the ahash_request
502 * handle. Any potentially existing state created by previous operations is
503 * discarded.
504 *
505 * Return: see crypto_ahash_final()
506 */
507 int crypto_ahash_init(struct ahash_request *req);
508
509 /**
510 * crypto_ahash_update() - add data to message digest for processing
511 * @req: ahash_request handle that was previously initialized with the
512 * crypto_ahash_init call.
513 *
514 * Updates the message digest state of the &ahash_request handle. The input data
515 * is pointed to by the scatter/gather list registered in the &ahash_request
516 * handle
517 *
518 * Return: see crypto_ahash_final()
519 */
520 int crypto_ahash_update(struct ahash_request *req);
521
522 /**
523 * DOC: Asynchronous Hash Request Handle
524 *
525 * The &ahash_request data structure contains all pointers to data
526 * required for the asynchronous cipher operation. This includes the cipher
527 * handle (which can be used by multiple &ahash_request instances), pointer
528 * to plaintext and the message digest output buffer, asynchronous callback
529 * function, etc. It acts as a handle to the ahash_request_* API calls in a
530 * similar way as ahash handle to the crypto_ahash_* API calls.
531 */
532
533 /**
534 * ahash_request_set_tfm() - update cipher handle reference in request
535 * @req: request handle to be modified
536 * @tfm: cipher handle that shall be added to the request handle
537 *
538 * Allow the caller to replace the existing ahash handle in the request
539 * data structure with a different one.
540 */
541 static inline void ahash_request_set_tfm(struct ahash_request *req,
542 struct crypto_ahash *tfm)
543 {
544 req->base.tfm = crypto_ahash_tfm(tfm);
545 }
546
547 /**
548 * ahash_request_alloc() - allocate request data structure
549 * @tfm: cipher handle to be registered with the request
550 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
551 *
552 * Allocate the request data structure that must be used with the ahash
553 * message digest API calls. During
554 * the allocation, the provided ahash handle
555 * is registered in the request data structure.
556 *
557 * Return: allocated request handle in case of success, or NULL if out of memory
558 */
559 static inline struct ahash_request *ahash_request_alloc_noprof(
560 struct crypto_ahash *tfm, gfp_t gfp)
561 {
562 struct ahash_request *req;
563
564 req = kmalloc_noprof(sizeof(struct ahash_request) +
565 crypto_ahash_reqsize(tfm), gfp);
566
567 if (likely(req))
568 ahash_request_set_tfm(req, tfm);
569
570 return req;
571 }
572 #define ahash_request_alloc(...) alloc_hooks(ahash_request_alloc_noprof(__VA_ARGS__))
573
574 /**
575 * ahash_request_free() - zeroize and free the request data structure
576 * @req: request data structure cipher handle to be freed
577 */
578 static inline void ahash_request_free(struct ahash_request *req)
579 {
580 kfree_sensitive(req);
581 }
582
583 static inline void ahash_request_zero(struct ahash_request *req)
584 {
585 memzero_explicit(req, sizeof(*req) +
586 crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
587 }
588
589 static inline struct ahash_request *ahash_request_cast(
590 struct crypto_async_request *req)
591 {
592 return container_of(req, struct ahash_request, base);
593 }
594
595 /**
596 * ahash_request_set_callback() - set asynchronous callback function
597 * @req: request handle
598 * @flags: specify zero or an ORing of the flags
599 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
600 * increase the wait queue beyond the initial maximum size;
601 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
602 * @compl: callback function pointer to be registered with the request handle
603 * @data: The data pointer refers to memory that is not used by the kernel
604 * crypto API, but provided to the callback function for it to use. Here,
605 * the caller can provide a reference to memory the callback function can
606 * operate on. As the callback function is invoked asynchronously to the
607 * related functionality, it may need to access data structures of the
608 * related functionality which can be referenced using this pointer. The
609 * callback function can access the memory via the "data" field in the
610 * &crypto_async_request data structure provided to the callback function.
611 *
612 * This function allows setting the callback function that is triggered once
613 * the cipher operation completes.
614 *
615 * The callback function is registered with the &ahash_request handle and
616 * must comply with the following template::
617 *
618 * void callback_function(struct crypto_async_request *req, int error)
619 */
620 static inline void ahash_request_set_callback(struct ahash_request *req,
621 u32 flags,
622 crypto_completion_t compl,
623 void *data)
624 {
625 req->base.complete = compl;
626 req->base.data = data;
627 req->base.flags = flags;
628 }
629
630 /**
631 * ahash_request_set_crypt() - set data buffers
632 * @req: ahash_request handle to be updated
633 * @src: source scatter/gather list
634 * @result: buffer that is filled with the message digest -- the caller must
635 * ensure that the buffer has sufficient space by, for example, calling
636 * crypto_ahash_digestsize()
637 * @nbytes: number of bytes to process from the source scatter/gather list
638 *
639 * By using this call, the caller references the source scatter/gather list.
640 * The source scatter/gather list points to the data the message digest is to
641 * be calculated for.
642 */
643 static inline void ahash_request_set_crypt(struct ahash_request *req,
644 struct scatterlist *src, u8 *result,
645 unsigned int nbytes)
646 {
647 req->src = src;
648 req->nbytes = nbytes;
649 req->result = result;
650 }
651
652 /**
653 * DOC: Synchronous Message Digest API
654 *
655 * The synchronous message digest API is used with the ciphers of type
656 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
657 *
658 * The message digest API is able to maintain state information for the
659 * caller.
660 *
661 * The synchronous message digest API can store user-related context in its
662 * shash_desc request data structure.
663 */
664
665 /**
666 * crypto_alloc_shash() - allocate message digest handle
667 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
668 * message digest cipher
669 * @type: specifies the type of the cipher
670 * @mask: specifies the mask for the cipher
671 *
672 * Allocate a cipher handle for a message digest. The returned &struct
673 * crypto_shash is the cipher handle that is required for any subsequent
674 * API invocation for that message digest.
675 *
676 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
677 * of an error, PTR_ERR() returns the error code.
678 */
679 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
680 u32 mask);
681
682 struct crypto_shash *crypto_clone_shash(struct crypto_shash *tfm);
683
684 int crypto_has_shash(const char *alg_name, u32 type, u32 mask);
685
686 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
687 {
688 return &tfm->base;
689 }
690
691 /**
692 * crypto_free_shash() - zeroize and free the message digest handle
693 * @tfm: cipher handle to be freed
694 *
695 * If @tfm is a NULL or error pointer, this function does nothing.
696 */
697 static inline void crypto_free_shash(struct crypto_shash *tfm)
698 {
699 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
700 }
701
702 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
703 {
704 return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
705 }
706
707 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
708 {
709 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
710 }
711
712 /**
713 * crypto_shash_blocksize() - obtain block size for cipher
714 * @tfm: cipher handle
715 *
716 * The block size for the message digest cipher referenced with the cipher
717 * handle is returned.
718 *
719 * Return: block size of cipher
720 */
721 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
722 {
723 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
724 }
725
726 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
727 {
728 return container_of(alg, struct shash_alg, base);
729 }
730
731 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
732 {
733 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
734 }
735
736 /**
737 * crypto_shash_digestsize() - obtain message digest size
738 * @tfm: cipher handle
739 *
740 * The size for the message digest created by the message digest cipher
741 * referenced with the cipher handle is returned.
742 *
743 * Return: digest size of cipher
744 */
745 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
746 {
747 return crypto_shash_alg(tfm)->digestsize;
748 }
749
750 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
751 {
752 return crypto_shash_alg(tfm)->statesize;
753 }
754
755 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
756 {
757 return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
758 }
759
760 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
761 {
762 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
763 }
764
765 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
766 {
767 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
768 }
769
770 /**
771 * crypto_shash_descsize() - obtain the operational state size
772 * @tfm: cipher handle
773 *
774 * The size of the operational state the cipher needs during operation is
775 * returned for the hash referenced with the cipher handle. This size is
776 * required to calculate the memory requirements to allow the caller allocating
777 * sufficient memory for operational state.
778 *
779 * The operational state is defined with struct shash_desc where the size of
780 * that data structure is to be calculated as
781 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
782 *
783 * Return: size of the operational state
784 */
785 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
786 {
787 return tfm->descsize;
788 }
789
790 static inline void *shash_desc_ctx(struct shash_desc *desc)
791 {
792 return desc->__ctx;
793 }
794
795 /**
796 * crypto_shash_setkey() - set key for message digest
797 * @tfm: cipher handle
798 * @key: buffer holding the key
799 * @keylen: length of the key in bytes
800 *
801 * The caller provided key is set for the keyed message digest cipher. The
802 * cipher handle must point to a keyed message digest cipher in order for this
803 * function to succeed.
804 *
805 * Context: Any context.
806 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
807 */
808 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
809 unsigned int keylen);
810
811 /**
812 * crypto_shash_digest() - calculate message digest for buffer
813 * @desc: see crypto_shash_final()
814 * @data: see crypto_shash_update()
815 * @len: see crypto_shash_update()
816 * @out: see crypto_shash_final()
817 *
818 * This function is a "short-hand" for the function calls of crypto_shash_init,
819 * crypto_shash_update and crypto_shash_final. The parameters have the same
820 * meaning as discussed for those separate three functions.
821 *
822 * Context: Any context.
823 * Return: 0 if the message digest creation was successful; < 0 if an error
824 * occurred
825 */
826 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
827 unsigned int len, u8 *out);
828
829 /**
830 * crypto_shash_tfm_digest() - calculate message digest for buffer
831 * @tfm: hash transformation object
832 * @data: see crypto_shash_update()
833 * @len: see crypto_shash_update()
834 * @out: see crypto_shash_final()
835 *
836 * This is a simplified version of crypto_shash_digest() for users who don't
837 * want to allocate their own hash descriptor (shash_desc). Instead,
838 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash)
839 * directly, and it allocates a hash descriptor on the stack internally.
840 * Note that this stack allocation may be fairly large.
841 *
842 * Context: Any context.
843 * Return: 0 on success; < 0 if an error occurred.
844 */
845 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
846 unsigned int len, u8 *out);
847
848 /**
849 * crypto_shash_export() - extract operational state for message digest
850 * @desc: reference to the operational state handle whose state is exported
851 * @out: output buffer of sufficient size that can hold the hash state
852 *
853 * This function exports the hash state of the operational state handle into the
854 * caller-allocated output buffer out which must have sufficient size (e.g. by
855 * calling crypto_shash_descsize).
856 *
857 * Context: Any context.
858 * Return: 0 if the export creation was successful; < 0 if an error occurred
859 */
860 int crypto_shash_export(struct shash_desc *desc, void *out);
861
862 /**
863 * crypto_shash_import() - import operational state
864 * @desc: reference to the operational state handle the state imported into
865 * @in: buffer holding the state
866 *
867 * This function imports the hash state into the operational state handle from
868 * the input buffer. That buffer should have been generated with the
869 * crypto_ahash_export function.
870 *
871 * Context: Any context.
872 * Return: 0 if the import was successful; < 0 if an error occurred
873 */
874 int crypto_shash_import(struct shash_desc *desc, const void *in);
875
876 /**
877 * crypto_shash_init() - (re)initialize message digest
878 * @desc: operational state handle that is already filled
879 *
880 * The call (re-)initializes the message digest referenced by the
881 * operational state handle. Any potentially existing state created by
882 * previous operations is discarded.
883 *
884 * Context: Any context.
885 * Return: 0 if the message digest initialization was successful; < 0 if an
886 * error occurred
887 */
888 static inline int crypto_shash_init(struct shash_desc *desc)
889 {
890 struct crypto_shash *tfm = desc->tfm;
891
892 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
893 return -ENOKEY;
894
895 return crypto_shash_alg(tfm)->init(desc);
896 }
897
898 /**
899 * crypto_shash_update() - add data to message digest for processing
900 * @desc: operational state handle that is already initialized
901 * @data: input data to be added to the message digest
902 * @len: length of the input data
903 *
904 * Updates the message digest state of the operational state handle.
905 *
906 * Context: Any context.
907 * Return: 0 if the message digest update was successful; < 0 if an error
908 * occurred
909 */
910 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
911 unsigned int len);
912
913 /**
914 * crypto_shash_final() - calculate message digest
915 * @desc: operational state handle that is already filled with data
916 * @out: output buffer filled with the message digest
917 *
918 * Finalize the message digest operation and create the message digest
919 * based on all data added to the cipher handle. The message digest is placed
920 * into the output buffer. The caller must ensure that the output buffer is
921 * large enough by using crypto_shash_digestsize.
922 *
923 * Context: Any context.
924 * Return: 0 if the message digest creation was successful; < 0 if an error
925 * occurred
926 */
927 int crypto_shash_final(struct shash_desc *desc, u8 *out);
928
929 /**
930 * crypto_shash_finup() - calculate message digest of buffer
931 * @desc: see crypto_shash_final()
932 * @data: see crypto_shash_update()
933 * @len: see crypto_shash_update()
934 * @out: see crypto_shash_final()
935 *
936 * This function is a "short-hand" for the function calls of
937 * crypto_shash_update and crypto_shash_final. The parameters have the same
938 * meaning as discussed for those separate functions.
939 *
940 * Context: Any context.
941 * Return: 0 if the message digest creation was successful; < 0 if an error
942 * occurred
943 */
944 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
945 unsigned int len, u8 *out);
946
947 static inline void shash_desc_zero(struct shash_desc *desc)
948 {
949 memzero_explicit(desc,
950 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
951 }
952
953 #endif /* _CRYPTO_HASH_H */
954
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