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v6.8
  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
 15struct 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 crypto_istat_hash - statistics for has algorithm
 28 * @hash_cnt:		number of hash requests
 29 * @hash_tlen:		total data size hashed
 30 * @err_cnt:		number of error for hash requests
 31 */
 32struct crypto_istat_hash {
 33	atomic64_t hash_cnt;
 34	atomic64_t hash_tlen;
 35	atomic64_t err_cnt;
 36};
 37
 38#ifdef CONFIG_CRYPTO_STATS
 39#define HASH_ALG_COMMON_STAT struct crypto_istat_hash stat;
 40#else
 41#define HASH_ALG_COMMON_STAT
 42#endif
 43
 44/*
 45 * struct hash_alg_common - define properties of message digest
 46 * @stat: Statistics for hash algorithm.
 47 * @digestsize: Size of the result of the transformation. A buffer of this size
 48 *	        must be available to the @final and @finup calls, so they can
 49 *	        store the resulting hash into it. For various predefined sizes,
 50 *	        search include/crypto/ using
 51 *	        git grep _DIGEST_SIZE include/crypto.
 52 * @statesize: Size of the block for partial state of the transformation. A
 53 *	       buffer of this size must be passed to the @export function as it
 54 *	       will save the partial state of the transformation into it. On the
 55 *	       other side, the @import function will load the state from a
 56 *	       buffer of this size as well.
 57 * @base: Start of data structure of cipher algorithm. The common data
 58 *	  structure of crypto_alg contains information common to all ciphers.
 59 *	  The hash_alg_common data structure now adds the hash-specific
 60 *	  information.
 61 */
 62#define HASH_ALG_COMMON {		\
 63	HASH_ALG_COMMON_STAT		\
 64					\
 65	unsigned int digestsize;	\
 66	unsigned int statesize;		\
 67					\
 68	struct crypto_alg base;		\
 69}
 70struct hash_alg_common HASH_ALG_COMMON;
 71
 72struct ahash_request {
 73	struct crypto_async_request base;
 74
 75	unsigned int nbytes;
 76	struct scatterlist *src;
 77	u8 *result;
 78
 79	/* This field may only be used by the ahash API code. */
 80	void *priv;
 81
 82	void *__ctx[] CRYPTO_MINALIGN_ATTR;
 83};
 84
 85/**
 86 * struct ahash_alg - asynchronous message digest definition
 87 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the
 88 *	  state of the HASH transformation at the beginning. This shall fill in
 89 *	  the internal structures used during the entire duration of the whole
 90 *	  transformation. No data processing happens at this point. Driver code
 91 *	  implementation must not use req->result.
 92 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
 93 *	   function actually pushes blocks of data from upper layers into the
 94 *	   driver, which then passes those to the hardware as seen fit. This
 95 *	   function must not finalize the HASH transformation by calculating the
 96 *	   final message digest as this only adds more data into the
 97 *	   transformation. This function shall not modify the transformation
 98 *	   context, as this function may be called in parallel with the same
 99 *	   transformation object. Data processing can happen synchronously
100 *	   [SHASH] or asynchronously [AHASH] at this point. Driver must not use
101 *	   req->result.
102 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
103 *	   transformation and retrieves the resulting hash from the driver and
104 *	   pushes it back to upper layers. No data processing happens at this
105 *	   point unless hardware requires it to finish the transformation
106 *	   (then the data buffered by the device driver is processed).
107 * @finup: **[optional]** Combination of @update and @final. This function is effectively a
108 *	   combination of @update and @final calls issued in sequence. As some
109 *	   hardware cannot do @update and @final separately, this callback was
110 *	   added to allow such hardware to be used at least by IPsec. Data
111 *	   processing can happen synchronously [SHASH] or asynchronously [AHASH]
112 *	   at this point.
113 * @digest: Combination of @init and @update and @final. This function
114 *	    effectively behaves as the entire chain of operations, @init,
115 *	    @update and @final issued in sequence. Just like @finup, this was
116 *	    added for hardware which cannot do even the @finup, but can only do
117 *	    the whole transformation in one run. Data processing can happen
118 *	    synchronously [SHASH] or asynchronously [AHASH] at this point.
119 * @setkey: Set optional key used by the hashing algorithm. Intended to push
120 *	    optional key used by the hashing algorithm from upper layers into
121 *	    the driver. This function can store the key in the transformation
122 *	    context or can outright program it into the hardware. In the former
123 *	    case, one must be careful to program the key into the hardware at
124 *	    appropriate time and one must be careful that .setkey() can be
125 *	    called multiple times during the existence of the transformation
126 *	    object. Not  all hashing algorithms do implement this function as it
127 *	    is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
128 *	    implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
129 *	    this function. This function must be called before any other of the
130 *	    @init, @update, @final, @finup, @digest is called. No data
131 *	    processing happens at this point.
132 * @export: Export partial state of the transformation. This function dumps the
133 *	    entire state of the ongoing transformation into a provided block of
134 *	    data so it can be @import 'ed back later on. This is useful in case
135 *	    you want to save partial result of the transformation after
136 *	    processing certain amount of data and reload this partial result
137 *	    multiple times later on for multiple re-use. No data processing
138 *	    happens at this point. Driver must not use req->result.
139 * @import: Import partial state of the transformation. This function loads the
140 *	    entire state of the ongoing transformation from a provided block of
141 *	    data so the transformation can continue from this point onward. No
142 *	    data processing happens at this point. Driver must not use
143 *	    req->result.
144 * @init_tfm: Initialize the cryptographic transformation object.
145 *	      This function is called only once at the instantiation
146 *	      time, right after the transformation context was
147 *	      allocated. In case the cryptographic hardware has
148 *	      some special requirements which need to be handled
149 *	      by software, this function shall check for the precise
150 *	      requirement of the transformation and put any software
151 *	      fallbacks in place.
152 * @exit_tfm: Deinitialize the cryptographic transformation object.
153 *	      This is a counterpart to @init_tfm, used to remove
154 *	      various changes set in @init_tfm.
155 * @clone_tfm: Copy transform into new object, may allocate memory.
156 * @halg: see struct hash_alg_common
157 */
158struct ahash_alg {
159	int (*init)(struct ahash_request *req);
160	int (*update)(struct ahash_request *req);
161	int (*final)(struct ahash_request *req);
162	int (*finup)(struct ahash_request *req);
163	int (*digest)(struct ahash_request *req);
164	int (*export)(struct ahash_request *req, void *out);
165	int (*import)(struct ahash_request *req, const void *in);
166	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
167		      unsigned int keylen);
168	int (*init_tfm)(struct crypto_ahash *tfm);
169	void (*exit_tfm)(struct crypto_ahash *tfm);
170	int (*clone_tfm)(struct crypto_ahash *dst, struct crypto_ahash *src);
171
172	struct hash_alg_common halg;
173};
174
175struct shash_desc {
176	struct crypto_shash *tfm;
177	void *__ctx[] __aligned(ARCH_SLAB_MINALIGN);
178};
179
180#define HASH_MAX_DIGESTSIZE	 64
181
182/*
183 * Worst case is hmac(sha3-224-generic).  Its context is a nested 'shash_desc'
184 * containing a 'struct sha3_state'.
185 */
186#define HASH_MAX_DESCSIZE	(sizeof(struct shash_desc) + 360)
187
 
 
188#define SHASH_DESC_ON_STACK(shash, ctx)					     \
189	char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \
190		__aligned(__alignof__(struct shash_desc));		     \
191	struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
192
193/**
194 * struct shash_alg - synchronous message digest definition
195 * @init: see struct ahash_alg
196 * @update: see struct ahash_alg
197 * @final: see struct ahash_alg
198 * @finup: see struct ahash_alg
199 * @digest: see struct ahash_alg
200 * @export: see struct ahash_alg
201 * @import: see struct ahash_alg
202 * @setkey: see struct ahash_alg
203 * @init_tfm: Initialize the cryptographic transformation object.
204 *	      This function is called only once at the instantiation
205 *	      time, right after the transformation context was
206 *	      allocated. In case the cryptographic hardware has
207 *	      some special requirements which need to be handled
208 *	      by software, this function shall check for the precise
209 *	      requirement of the transformation and put any software
210 *	      fallbacks in place.
211 * @exit_tfm: Deinitialize the cryptographic transformation object.
212 *	      This is a counterpart to @init_tfm, used to remove
213 *	      various changes set in @init_tfm.
214 * @clone_tfm: Copy transform into new object, may allocate memory.
 
215 * @descsize: Size of the operational state for the message digest. This state
216 * 	      size is the memory size that needs to be allocated for
217 *	      shash_desc.__ctx
218 * @halg: see struct hash_alg_common
219 * @HASH_ALG_COMMON: see struct hash_alg_common
220 */
221struct shash_alg {
222	int (*init)(struct shash_desc *desc);
223	int (*update)(struct shash_desc *desc, const u8 *data,
224		      unsigned int len);
225	int (*final)(struct shash_desc *desc, u8 *out);
226	int (*finup)(struct shash_desc *desc, const u8 *data,
227		     unsigned int len, u8 *out);
228	int (*digest)(struct shash_desc *desc, const u8 *data,
229		      unsigned int len, u8 *out);
230	int (*export)(struct shash_desc *desc, void *out);
231	int (*import)(struct shash_desc *desc, const void *in);
232	int (*setkey)(struct crypto_shash *tfm, const u8 *key,
233		      unsigned int keylen);
234	int (*init_tfm)(struct crypto_shash *tfm);
235	void (*exit_tfm)(struct crypto_shash *tfm);
236	int (*clone_tfm)(struct crypto_shash *dst, struct crypto_shash *src);
237
238	unsigned int descsize;
239
240	union {
241		struct HASH_ALG_COMMON;
242		struct hash_alg_common halg;
243	};
 
 
244};
245#undef HASH_ALG_COMMON
246#undef HASH_ALG_COMMON_STAT
247
248struct crypto_ahash {
249	bool using_shash; /* Underlying algorithm is shash, not ahash */
250	unsigned int statesize;
 
 
 
 
 
 
 
 
251	unsigned int reqsize;
252	struct crypto_tfm base;
253};
254
255struct crypto_shash {
256	unsigned int descsize;
257	struct crypto_tfm base;
258};
259
260/**
261 * DOC: Asynchronous Message Digest API
262 *
263 * The asynchronous message digest API is used with the ciphers of type
264 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
265 *
266 * The asynchronous cipher operation discussion provided for the
267 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well.
268 */
269
270static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
271{
272	return container_of(tfm, struct crypto_ahash, base);
273}
274
275/**
276 * crypto_alloc_ahash() - allocate ahash cipher handle
277 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
278 *	      ahash cipher
279 * @type: specifies the type of the cipher
280 * @mask: specifies the mask for the cipher
281 *
282 * Allocate a cipher handle for an ahash. The returned struct
283 * crypto_ahash is the cipher handle that is required for any subsequent
284 * API invocation for that ahash.
285 *
286 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
287 *	   of an error, PTR_ERR() returns the error code.
288 */
289struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
290					u32 mask);
291
292struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *tfm);
293
294static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
295{
296	return &tfm->base;
297}
298
299/**
300 * crypto_free_ahash() - zeroize and free the ahash handle
301 * @tfm: cipher handle to be freed
302 *
303 * If @tfm is a NULL or error pointer, this function does nothing.
304 */
305static inline void crypto_free_ahash(struct crypto_ahash *tfm)
306{
307	crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
308}
309
310/**
311 * crypto_has_ahash() - Search for the availability of an ahash.
312 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
313 *	      ahash
314 * @type: specifies the type of the ahash
315 * @mask: specifies the mask for the ahash
316 *
317 * Return: true when the ahash is known to the kernel crypto API; false
318 *	   otherwise
319 */
320int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
321
322static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
323{
324	return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
325}
326
327static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
328{
329	return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
330}
331
 
 
 
 
 
 
332/**
333 * crypto_ahash_blocksize() - obtain block size for cipher
334 * @tfm: cipher handle
335 *
336 * The block size for the message digest cipher referenced with the cipher
337 * handle is returned.
338 *
339 * Return: block size of cipher
340 */
341static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
342{
343	return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
344}
345
346static inline struct hash_alg_common *__crypto_hash_alg_common(
347	struct crypto_alg *alg)
348{
349	return container_of(alg, struct hash_alg_common, base);
350}
351
352static inline struct hash_alg_common *crypto_hash_alg_common(
353	struct crypto_ahash *tfm)
354{
355	return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
356}
357
358/**
359 * crypto_ahash_digestsize() - obtain message digest size
360 * @tfm: cipher handle
361 *
362 * The size for the message digest created by the message digest cipher
363 * referenced with the cipher handle is returned.
364 *
365 *
366 * Return: message digest size of cipher
367 */
368static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
369{
370	return crypto_hash_alg_common(tfm)->digestsize;
371}
372
373/**
374 * crypto_ahash_statesize() - obtain size of the ahash state
375 * @tfm: cipher handle
376 *
377 * Return the size of the ahash state. With the crypto_ahash_export()
378 * function, the caller can export the state into a buffer whose size is
379 * defined with this function.
380 *
381 * Return: size of the ahash state
382 */
383static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
384{
385	return tfm->statesize;
386}
387
388static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
389{
390	return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
391}
392
393static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
394{
395	crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
396}
397
398static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
399{
400	crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
401}
402
403/**
404 * crypto_ahash_reqtfm() - obtain cipher handle from request
405 * @req: asynchronous request handle that contains the reference to the ahash
406 *	 cipher handle
407 *
408 * Return the ahash cipher handle that is registered with the asynchronous
409 * request handle ahash_request.
410 *
411 * Return: ahash cipher handle
412 */
413static inline struct crypto_ahash *crypto_ahash_reqtfm(
414	struct ahash_request *req)
415{
416	return __crypto_ahash_cast(req->base.tfm);
417}
418
419/**
420 * crypto_ahash_reqsize() - obtain size of the request data structure
421 * @tfm: cipher handle
422 *
423 * Return: size of the request data
424 */
425static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
426{
427	return tfm->reqsize;
428}
429
430static inline void *ahash_request_ctx(struct ahash_request *req)
431{
432	return req->__ctx;
433}
434
435/**
436 * crypto_ahash_setkey - set key for cipher handle
437 * @tfm: cipher handle
438 * @key: buffer holding the key
439 * @keylen: length of the key in bytes
440 *
441 * The caller provided key is set for the ahash cipher. The cipher
442 * handle must point to a keyed hash in order for this function to succeed.
443 *
444 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
445 */
446int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
447			unsigned int keylen);
448
449/**
450 * crypto_ahash_finup() - update and finalize message digest
451 * @req: reference to the ahash_request handle that holds all information
452 *	 needed to perform the cipher operation
453 *
454 * This function is a "short-hand" for the function calls of
455 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
456 * meaning as discussed for those separate functions.
457 *
458 * Return: see crypto_ahash_final()
459 */
460int crypto_ahash_finup(struct ahash_request *req);
461
462/**
463 * crypto_ahash_final() - calculate message digest
464 * @req: reference to the ahash_request handle that holds all information
465 *	 needed to perform the cipher operation
466 *
467 * Finalize the message digest operation and create the message digest
468 * based on all data added to the cipher handle. The message digest is placed
469 * into the output buffer registered with the ahash_request handle.
470 *
471 * Return:
472 * 0		if the message digest was successfully calculated;
473 * -EINPROGRESS	if data is fed into hardware (DMA) or queued for later;
474 * -EBUSY	if queue is full and request should be resubmitted later;
475 * other < 0	if an error occurred
476 */
477int crypto_ahash_final(struct ahash_request *req);
478
479/**
480 * crypto_ahash_digest() - calculate message digest for a buffer
481 * @req: reference to the ahash_request handle that holds all information
482 *	 needed to perform the cipher operation
483 *
484 * This function is a "short-hand" for the function calls of crypto_ahash_init,
485 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
486 * meaning as discussed for those separate three functions.
487 *
488 * Return: see crypto_ahash_final()
489 */
490int crypto_ahash_digest(struct ahash_request *req);
491
492/**
493 * crypto_ahash_export() - extract current message digest state
494 * @req: reference to the ahash_request handle whose state is exported
495 * @out: output buffer of sufficient size that can hold the hash state
496 *
497 * This function exports the hash state of the ahash_request handle into the
498 * caller-allocated output buffer out which must have sufficient size (e.g. by
499 * calling crypto_ahash_statesize()).
500 *
501 * Return: 0 if the export was successful; < 0 if an error occurred
502 */
503int crypto_ahash_export(struct ahash_request *req, void *out);
 
 
 
504
505/**
506 * crypto_ahash_import() - import message digest state
507 * @req: reference to ahash_request handle the state is imported into
508 * @in: buffer holding the state
509 *
510 * This function imports the hash state into the ahash_request handle from the
511 * input buffer. That buffer should have been generated with the
512 * crypto_ahash_export function.
513 *
514 * Return: 0 if the import was successful; < 0 if an error occurred
515 */
516int crypto_ahash_import(struct ahash_request *req, const void *in);
 
 
 
 
 
 
 
 
517
518/**
519 * crypto_ahash_init() - (re)initialize message digest handle
520 * @req: ahash_request handle that already is initialized with all necessary
521 *	 data using the ahash_request_* API functions
522 *
523 * The call (re-)initializes the message digest referenced by the ahash_request
524 * handle. Any potentially existing state created by previous operations is
525 * discarded.
526 *
527 * Return: see crypto_ahash_final()
528 */
529int crypto_ahash_init(struct ahash_request *req);
 
 
 
 
 
 
 
 
530
531/**
532 * crypto_ahash_update() - add data to message digest for processing
533 * @req: ahash_request handle that was previously initialized with the
534 *	 crypto_ahash_init call.
535 *
536 * Updates the message digest state of the &ahash_request handle. The input data
537 * is pointed to by the scatter/gather list registered in the &ahash_request
538 * handle
539 *
540 * Return: see crypto_ahash_final()
541 */
542int crypto_ahash_update(struct ahash_request *req);
 
 
 
 
 
 
 
 
 
 
 
543
544/**
545 * DOC: Asynchronous Hash Request Handle
546 *
547 * The &ahash_request data structure contains all pointers to data
548 * required for the asynchronous cipher operation. This includes the cipher
549 * handle (which can be used by multiple &ahash_request instances), pointer
550 * to plaintext and the message digest output buffer, asynchronous callback
551 * function, etc. It acts as a handle to the ahash_request_* API calls in a
552 * similar way as ahash handle to the crypto_ahash_* API calls.
553 */
554
555/**
556 * ahash_request_set_tfm() - update cipher handle reference in request
557 * @req: request handle to be modified
558 * @tfm: cipher handle that shall be added to the request handle
559 *
560 * Allow the caller to replace the existing ahash handle in the request
561 * data structure with a different one.
562 */
563static inline void ahash_request_set_tfm(struct ahash_request *req,
564					 struct crypto_ahash *tfm)
565{
566	req->base.tfm = crypto_ahash_tfm(tfm);
567}
568
569/**
570 * ahash_request_alloc() - allocate request data structure
571 * @tfm: cipher handle to be registered with the request
572 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
573 *
574 * Allocate the request data structure that must be used with the ahash
575 * message digest API calls. During
576 * the allocation, the provided ahash handle
577 * is registered in the request data structure.
578 *
579 * Return: allocated request handle in case of success, or NULL if out of memory
580 */
581static inline struct ahash_request *ahash_request_alloc(
582	struct crypto_ahash *tfm, gfp_t gfp)
583{
584	struct ahash_request *req;
585
586	req = kmalloc(sizeof(struct ahash_request) +
587		      crypto_ahash_reqsize(tfm), gfp);
588
589	if (likely(req))
590		ahash_request_set_tfm(req, tfm);
591
592	return req;
593}
594
595/**
596 * ahash_request_free() - zeroize and free the request data structure
597 * @req: request data structure cipher handle to be freed
598 */
599static inline void ahash_request_free(struct ahash_request *req)
600{
601	kfree_sensitive(req);
602}
603
604static inline void ahash_request_zero(struct ahash_request *req)
605{
606	memzero_explicit(req, sizeof(*req) +
607			      crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
608}
609
610static inline struct ahash_request *ahash_request_cast(
611	struct crypto_async_request *req)
612{
613	return container_of(req, struct ahash_request, base);
614}
615
616/**
617 * ahash_request_set_callback() - set asynchronous callback function
618 * @req: request handle
619 * @flags: specify zero or an ORing of the flags
620 *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
621 *	   increase the wait queue beyond the initial maximum size;
622 *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
623 * @compl: callback function pointer to be registered with the request handle
624 * @data: The data pointer refers to memory that is not used by the kernel
625 *	  crypto API, but provided to the callback function for it to use. Here,
626 *	  the caller can provide a reference to memory the callback function can
627 *	  operate on. As the callback function is invoked asynchronously to the
628 *	  related functionality, it may need to access data structures of the
629 *	  related functionality which can be referenced using this pointer. The
630 *	  callback function can access the memory via the "data" field in the
631 *	  &crypto_async_request data structure provided to the callback function.
632 *
633 * This function allows setting the callback function that is triggered once
634 * the cipher operation completes.
635 *
636 * The callback function is registered with the &ahash_request handle and
637 * must comply with the following template::
638 *
639 *	void callback_function(struct crypto_async_request *req, int error)
640 */
641static inline void ahash_request_set_callback(struct ahash_request *req,
642					      u32 flags,
643					      crypto_completion_t compl,
644					      void *data)
645{
646	req->base.complete = compl;
647	req->base.data = data;
648	req->base.flags = flags;
649}
650
651/**
652 * ahash_request_set_crypt() - set data buffers
653 * @req: ahash_request handle to be updated
654 * @src: source scatter/gather list
655 * @result: buffer that is filled with the message digest -- the caller must
656 *	    ensure that the buffer has sufficient space by, for example, calling
657 *	    crypto_ahash_digestsize()
658 * @nbytes: number of bytes to process from the source scatter/gather list
659 *
660 * By using this call, the caller references the source scatter/gather list.
661 * The source scatter/gather list points to the data the message digest is to
662 * be calculated for.
663 */
664static inline void ahash_request_set_crypt(struct ahash_request *req,
665					   struct scatterlist *src, u8 *result,
666					   unsigned int nbytes)
667{
668	req->src = src;
669	req->nbytes = nbytes;
670	req->result = result;
671}
672
673/**
674 * DOC: Synchronous Message Digest API
675 *
676 * The synchronous message digest API is used with the ciphers of type
677 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
678 *
679 * The message digest API is able to maintain state information for the
680 * caller.
681 *
682 * The synchronous message digest API can store user-related context in its
683 * shash_desc request data structure.
684 */
685
686/**
687 * crypto_alloc_shash() - allocate message digest handle
688 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
689 *	      message digest cipher
690 * @type: specifies the type of the cipher
691 * @mask: specifies the mask for the cipher
692 *
693 * Allocate a cipher handle for a message digest. The returned &struct
694 * crypto_shash is the cipher handle that is required for any subsequent
695 * API invocation for that message digest.
696 *
697 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
698 *	   of an error, PTR_ERR() returns the error code.
699 */
700struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
701					u32 mask);
702
703struct crypto_shash *crypto_clone_shash(struct crypto_shash *tfm);
704
705int crypto_has_shash(const char *alg_name, u32 type, u32 mask);
706
707static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
708{
709	return &tfm->base;
710}
711
712/**
713 * crypto_free_shash() - zeroize and free the message digest handle
714 * @tfm: cipher handle to be freed
715 *
716 * If @tfm is a NULL or error pointer, this function does nothing.
717 */
718static inline void crypto_free_shash(struct crypto_shash *tfm)
719{
720	crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
721}
722
723static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
724{
725	return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
726}
727
728static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
729{
730	return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
731}
732
 
 
 
 
 
 
733/**
734 * crypto_shash_blocksize() - obtain block size for cipher
735 * @tfm: cipher handle
736 *
737 * The block size for the message digest cipher referenced with the cipher
738 * handle is returned.
739 *
740 * Return: block size of cipher
741 */
742static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
743{
744	return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
745}
746
747static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
748{
749	return container_of(alg, struct shash_alg, base);
750}
751
752static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
753{
754	return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
755}
756
757/**
758 * crypto_shash_digestsize() - obtain message digest size
759 * @tfm: cipher handle
760 *
761 * The size for the message digest created by the message digest cipher
762 * referenced with the cipher handle is returned.
763 *
764 * Return: digest size of cipher
765 */
766static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
767{
768	return crypto_shash_alg(tfm)->digestsize;
769}
770
771static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
772{
773	return crypto_shash_alg(tfm)->statesize;
774}
775
776static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
777{
778	return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
779}
780
781static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
782{
783	crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
784}
785
786static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
787{
788	crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
789}
790
791/**
792 * crypto_shash_descsize() - obtain the operational state size
793 * @tfm: cipher handle
794 *
795 * The size of the operational state the cipher needs during operation is
796 * returned for the hash referenced with the cipher handle. This size is
797 * required to calculate the memory requirements to allow the caller allocating
798 * sufficient memory for operational state.
799 *
800 * The operational state is defined with struct shash_desc where the size of
801 * that data structure is to be calculated as
802 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
803 *
804 * Return: size of the operational state
805 */
806static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
807{
808	return tfm->descsize;
809}
810
811static inline void *shash_desc_ctx(struct shash_desc *desc)
812{
813	return desc->__ctx;
814}
815
816/**
817 * crypto_shash_setkey() - set key for message digest
818 * @tfm: cipher handle
819 * @key: buffer holding the key
820 * @keylen: length of the key in bytes
821 *
822 * The caller provided key is set for the keyed message digest cipher. The
823 * cipher handle must point to a keyed message digest cipher in order for this
824 * function to succeed.
825 *
826 * Context: Any context.
827 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
828 */
829int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
830			unsigned int keylen);
831
832/**
833 * crypto_shash_digest() - calculate message digest for buffer
834 * @desc: see crypto_shash_final()
835 * @data: see crypto_shash_update()
836 * @len: see crypto_shash_update()
837 * @out: see crypto_shash_final()
838 *
839 * This function is a "short-hand" for the function calls of crypto_shash_init,
840 * crypto_shash_update and crypto_shash_final. The parameters have the same
841 * meaning as discussed for those separate three functions.
842 *
843 * Context: Any context.
844 * Return: 0 if the message digest creation was successful; < 0 if an error
845 *	   occurred
846 */
847int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
848			unsigned int len, u8 *out);
849
850/**
851 * crypto_shash_tfm_digest() - calculate message digest for buffer
852 * @tfm: hash transformation object
853 * @data: see crypto_shash_update()
854 * @len: see crypto_shash_update()
855 * @out: see crypto_shash_final()
856 *
857 * This is a simplified version of crypto_shash_digest() for users who don't
858 * want to allocate their own hash descriptor (shash_desc).  Instead,
859 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash)
860 * directly, and it allocates a hash descriptor on the stack internally.
861 * Note that this stack allocation may be fairly large.
862 *
863 * Context: Any context.
864 * Return: 0 on success; < 0 if an error occurred.
865 */
866int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
867			    unsigned int len, u8 *out);
868
869/**
870 * crypto_shash_export() - extract operational state for message digest
871 * @desc: reference to the operational state handle whose state is exported
872 * @out: output buffer of sufficient size that can hold the hash state
873 *
874 * This function exports the hash state of the operational state handle into the
875 * caller-allocated output buffer out which must have sufficient size (e.g. by
876 * calling crypto_shash_descsize).
877 *
878 * Context: Any context.
879 * Return: 0 if the export creation was successful; < 0 if an error occurred
880 */
881int crypto_shash_export(struct shash_desc *desc, void *out);
 
 
 
882
883/**
884 * crypto_shash_import() - import operational state
885 * @desc: reference to the operational state handle the state imported into
886 * @in: buffer holding the state
887 *
888 * This function imports the hash state into the operational state handle from
889 * the input buffer. That buffer should have been generated with the
890 * crypto_ahash_export function.
891 *
892 * Context: Any context.
893 * Return: 0 if the import was successful; < 0 if an error occurred
894 */
895int crypto_shash_import(struct shash_desc *desc, const void *in);
 
 
 
 
 
 
 
 
896
897/**
898 * crypto_shash_init() - (re)initialize message digest
899 * @desc: operational state handle that is already filled
900 *
901 * The call (re-)initializes the message digest referenced by the
902 * operational state handle. Any potentially existing state created by
903 * previous operations is discarded.
904 *
905 * Context: Any context.
906 * Return: 0 if the message digest initialization was successful; < 0 if an
907 *	   error occurred
908 */
909static inline int crypto_shash_init(struct shash_desc *desc)
910{
911	struct crypto_shash *tfm = desc->tfm;
912
913	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
914		return -ENOKEY;
915
916	return crypto_shash_alg(tfm)->init(desc);
917}
918
919/**
920 * crypto_shash_update() - add data to message digest for processing
921 * @desc: operational state handle that is already initialized
922 * @data: input data to be added to the message digest
923 * @len: length of the input data
924 *
925 * Updates the message digest state of the operational state handle.
926 *
927 * Context: Any context.
928 * Return: 0 if the message digest update was successful; < 0 if an error
929 *	   occurred
930 */
931int crypto_shash_update(struct shash_desc *desc, const u8 *data,
932			unsigned int len);
933
934/**
935 * crypto_shash_final() - calculate message digest
936 * @desc: operational state handle that is already filled with data
937 * @out: output buffer filled with the message digest
938 *
939 * Finalize the message digest operation and create the message digest
940 * based on all data added to the cipher handle. The message digest is placed
941 * into the output buffer. The caller must ensure that the output buffer is
942 * large enough by using crypto_shash_digestsize.
943 *
944 * Context: Any context.
945 * Return: 0 if the message digest creation was successful; < 0 if an error
946 *	   occurred
947 */
948int crypto_shash_final(struct shash_desc *desc, u8 *out);
949
950/**
951 * crypto_shash_finup() - calculate message digest of buffer
952 * @desc: see crypto_shash_final()
953 * @data: see crypto_shash_update()
954 * @len: see crypto_shash_update()
955 * @out: see crypto_shash_final()
956 *
957 * This function is a "short-hand" for the function calls of
958 * crypto_shash_update and crypto_shash_final. The parameters have the same
959 * meaning as discussed for those separate functions.
960 *
961 * Context: Any context.
962 * Return: 0 if the message digest creation was successful; < 0 if an error
963 *	   occurred
964 */
965int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
966		       unsigned int len, u8 *out);
967
968static inline void shash_desc_zero(struct shash_desc *desc)
969{
970	memzero_explicit(desc,
971			 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
972}
973
974#endif	/* _CRYPTO_HASH_H */
v6.2
   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/crypto.h>
  12#include <linux/string.h>
  13
  14struct crypto_ahash;
  15
  16/**
  17 * DOC: Message Digest Algorithm Definitions
  18 *
  19 * These data structures define modular message digest algorithm
  20 * implementations, managed via crypto_register_ahash(),
  21 * crypto_register_shash(), crypto_unregister_ahash() and
  22 * crypto_unregister_shash().
  23 */
  24
  25/**
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  26 * struct hash_alg_common - define properties of message digest
 
  27 * @digestsize: Size of the result of the transformation. A buffer of this size
  28 *	        must be available to the @final and @finup calls, so they can
  29 *	        store the resulting hash into it. For various predefined sizes,
  30 *	        search include/crypto/ using
  31 *	        git grep _DIGEST_SIZE include/crypto.
  32 * @statesize: Size of the block for partial state of the transformation. A
  33 *	       buffer of this size must be passed to the @export function as it
  34 *	       will save the partial state of the transformation into it. On the
  35 *	       other side, the @import function will load the state from a
  36 *	       buffer of this size as well.
  37 * @base: Start of data structure of cipher algorithm. The common data
  38 *	  structure of crypto_alg contains information common to all ciphers.
  39 *	  The hash_alg_common data structure now adds the hash-specific
  40 *	  information.
  41 */
  42struct hash_alg_common {
  43	unsigned int digestsize;
  44	unsigned int statesize;
  45
  46	struct crypto_alg base;
  47};
 
 
 
  48
  49struct ahash_request {
  50	struct crypto_async_request base;
  51
  52	unsigned int nbytes;
  53	struct scatterlist *src;
  54	u8 *result;
  55
  56	/* This field may only be used by the ahash API code. */
  57	void *priv;
  58
  59	void *__ctx[] CRYPTO_MINALIGN_ATTR;
  60};
  61
  62/**
  63 * struct ahash_alg - asynchronous message digest definition
  64 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the
  65 *	  state of the HASH transformation at the beginning. This shall fill in
  66 *	  the internal structures used during the entire duration of the whole
  67 *	  transformation. No data processing happens at this point. Driver code
  68 *	  implementation must not use req->result.
  69 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
  70 *	   function actually pushes blocks of data from upper layers into the
  71 *	   driver, which then passes those to the hardware as seen fit. This
  72 *	   function must not finalize the HASH transformation by calculating the
  73 *	   final message digest as this only adds more data into the
  74 *	   transformation. This function shall not modify the transformation
  75 *	   context, as this function may be called in parallel with the same
  76 *	   transformation object. Data processing can happen synchronously
  77 *	   [SHASH] or asynchronously [AHASH] at this point. Driver must not use
  78 *	   req->result.
  79 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
  80 *	   transformation and retrieves the resulting hash from the driver and
  81 *	   pushes it back to upper layers. No data processing happens at this
  82 *	   point unless hardware requires it to finish the transformation
  83 *	   (then the data buffered by the device driver is processed).
  84 * @finup: **[optional]** Combination of @update and @final. This function is effectively a
  85 *	   combination of @update and @final calls issued in sequence. As some
  86 *	   hardware cannot do @update and @final separately, this callback was
  87 *	   added to allow such hardware to be used at least by IPsec. Data
  88 *	   processing can happen synchronously [SHASH] or asynchronously [AHASH]
  89 *	   at this point.
  90 * @digest: Combination of @init and @update and @final. This function
  91 *	    effectively behaves as the entire chain of operations, @init,
  92 *	    @update and @final issued in sequence. Just like @finup, this was
  93 *	    added for hardware which cannot do even the @finup, but can only do
  94 *	    the whole transformation in one run. Data processing can happen
  95 *	    synchronously [SHASH] or asynchronously [AHASH] at this point.
  96 * @setkey: Set optional key used by the hashing algorithm. Intended to push
  97 *	    optional key used by the hashing algorithm from upper layers into
  98 *	    the driver. This function can store the key in the transformation
  99 *	    context or can outright program it into the hardware. In the former
 100 *	    case, one must be careful to program the key into the hardware at
 101 *	    appropriate time and one must be careful that .setkey() can be
 102 *	    called multiple times during the existence of the transformation
 103 *	    object. Not  all hashing algorithms do implement this function as it
 104 *	    is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
 105 *	    implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
 106 *	    this function. This function must be called before any other of the
 107 *	    @init, @update, @final, @finup, @digest is called. No data
 108 *	    processing happens at this point.
 109 * @export: Export partial state of the transformation. This function dumps the
 110 *	    entire state of the ongoing transformation into a provided block of
 111 *	    data so it can be @import 'ed back later on. This is useful in case
 112 *	    you want to save partial result of the transformation after
 113 *	    processing certain amount of data and reload this partial result
 114 *	    multiple times later on for multiple re-use. No data processing
 115 *	    happens at this point. Driver must not use req->result.
 116 * @import: Import partial state of the transformation. This function loads the
 117 *	    entire state of the ongoing transformation from a provided block of
 118 *	    data so the transformation can continue from this point onward. No
 119 *	    data processing happens at this point. Driver must not use
 120 *	    req->result.
 121 * @init_tfm: Initialize the cryptographic transformation object.
 122 *	      This function is called only once at the instantiation
 123 *	      time, right after the transformation context was
 124 *	      allocated. In case the cryptographic hardware has
 125 *	      some special requirements which need to be handled
 126 *	      by software, this function shall check for the precise
 127 *	      requirement of the transformation and put any software
 128 *	      fallbacks in place.
 129 * @exit_tfm: Deinitialize the cryptographic transformation object.
 130 *	      This is a counterpart to @init_tfm, used to remove
 131 *	      various changes set in @init_tfm.
 
 132 * @halg: see struct hash_alg_common
 133 */
 134struct ahash_alg {
 135	int (*init)(struct ahash_request *req);
 136	int (*update)(struct ahash_request *req);
 137	int (*final)(struct ahash_request *req);
 138	int (*finup)(struct ahash_request *req);
 139	int (*digest)(struct ahash_request *req);
 140	int (*export)(struct ahash_request *req, void *out);
 141	int (*import)(struct ahash_request *req, const void *in);
 142	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
 143		      unsigned int keylen);
 144	int (*init_tfm)(struct crypto_ahash *tfm);
 145	void (*exit_tfm)(struct crypto_ahash *tfm);
 
 146
 147	struct hash_alg_common halg;
 148};
 149
 150struct shash_desc {
 151	struct crypto_shash *tfm;
 152	void *__ctx[] __aligned(ARCH_SLAB_MINALIGN);
 153};
 154
 155#define HASH_MAX_DIGESTSIZE	 64
 156
 157/*
 158 * Worst case is hmac(sha3-224-generic).  Its context is a nested 'shash_desc'
 159 * containing a 'struct sha3_state'.
 160 */
 161#define HASH_MAX_DESCSIZE	(sizeof(struct shash_desc) + 360)
 162
 163#define HASH_MAX_STATESIZE	512
 164
 165#define SHASH_DESC_ON_STACK(shash, ctx)					     \
 166	char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \
 167		__aligned(__alignof__(struct shash_desc));		     \
 168	struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
 169
 170/**
 171 * struct shash_alg - synchronous message digest definition
 172 * @init: see struct ahash_alg
 173 * @update: see struct ahash_alg
 174 * @final: see struct ahash_alg
 175 * @finup: see struct ahash_alg
 176 * @digest: see struct ahash_alg
 177 * @export: see struct ahash_alg
 178 * @import: see struct ahash_alg
 179 * @setkey: see struct ahash_alg
 180 * @init_tfm: Initialize the cryptographic transformation object.
 181 *	      This function is called only once at the instantiation
 182 *	      time, right after the transformation context was
 183 *	      allocated. In case the cryptographic hardware has
 184 *	      some special requirements which need to be handled
 185 *	      by software, this function shall check for the precise
 186 *	      requirement of the transformation and put any software
 187 *	      fallbacks in place.
 188 * @exit_tfm: Deinitialize the cryptographic transformation object.
 189 *	      This is a counterpart to @init_tfm, used to remove
 190 *	      various changes set in @init_tfm.
 191 * @digestsize: see struct ahash_alg
 192 * @statesize: see struct ahash_alg
 193 * @descsize: Size of the operational state for the message digest. This state
 194 * 	      size is the memory size that needs to be allocated for
 195 *	      shash_desc.__ctx
 196 * @base: internally used
 
 197 */
 198struct shash_alg {
 199	int (*init)(struct shash_desc *desc);
 200	int (*update)(struct shash_desc *desc, const u8 *data,
 201		      unsigned int len);
 202	int (*final)(struct shash_desc *desc, u8 *out);
 203	int (*finup)(struct shash_desc *desc, const u8 *data,
 204		     unsigned int len, u8 *out);
 205	int (*digest)(struct shash_desc *desc, const u8 *data,
 206		      unsigned int len, u8 *out);
 207	int (*export)(struct shash_desc *desc, void *out);
 208	int (*import)(struct shash_desc *desc, const void *in);
 209	int (*setkey)(struct crypto_shash *tfm, const u8 *key,
 210		      unsigned int keylen);
 211	int (*init_tfm)(struct crypto_shash *tfm);
 212	void (*exit_tfm)(struct crypto_shash *tfm);
 
 213
 214	unsigned int descsize;
 215
 216	/* These fields must match hash_alg_common. */
 217	unsigned int digestsize
 218		__attribute__ ((aligned(__alignof__(struct hash_alg_common))));
 219	unsigned int statesize;
 220
 221	struct crypto_alg base;
 222};
 
 
 223
 224struct crypto_ahash {
 225	int (*init)(struct ahash_request *req);
 226	int (*update)(struct ahash_request *req);
 227	int (*final)(struct ahash_request *req);
 228	int (*finup)(struct ahash_request *req);
 229	int (*digest)(struct ahash_request *req);
 230	int (*export)(struct ahash_request *req, void *out);
 231	int (*import)(struct ahash_request *req, const void *in);
 232	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
 233		      unsigned int keylen);
 234
 235	unsigned int reqsize;
 236	struct crypto_tfm base;
 237};
 238
 239struct crypto_shash {
 240	unsigned int descsize;
 241	struct crypto_tfm base;
 242};
 243
 244/**
 245 * DOC: Asynchronous Message Digest API
 246 *
 247 * The asynchronous message digest API is used with the ciphers of type
 248 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
 249 *
 250 * The asynchronous cipher operation discussion provided for the
 251 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well.
 252 */
 253
 254static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
 255{
 256	return container_of(tfm, struct crypto_ahash, base);
 257}
 258
 259/**
 260 * crypto_alloc_ahash() - allocate ahash cipher handle
 261 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
 262 *	      ahash cipher
 263 * @type: specifies the type of the cipher
 264 * @mask: specifies the mask for the cipher
 265 *
 266 * Allocate a cipher handle for an ahash. The returned struct
 267 * crypto_ahash is the cipher handle that is required for any subsequent
 268 * API invocation for that ahash.
 269 *
 270 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
 271 *	   of an error, PTR_ERR() returns the error code.
 272 */
 273struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
 274					u32 mask);
 275
 
 
 276static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
 277{
 278	return &tfm->base;
 279}
 280
 281/**
 282 * crypto_free_ahash() - zeroize and free the ahash handle
 283 * @tfm: cipher handle to be freed
 284 *
 285 * If @tfm is a NULL or error pointer, this function does nothing.
 286 */
 287static inline void crypto_free_ahash(struct crypto_ahash *tfm)
 288{
 289	crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
 290}
 291
 292/**
 293 * crypto_has_ahash() - Search for the availability of an ahash.
 294 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
 295 *	      ahash
 296 * @type: specifies the type of the ahash
 297 * @mask: specifies the mask for the ahash
 298 *
 299 * Return: true when the ahash is known to the kernel crypto API; false
 300 *	   otherwise
 301 */
 302int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
 303
 304static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
 305{
 306	return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
 307}
 308
 309static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
 310{
 311	return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
 312}
 313
 314static inline unsigned int crypto_ahash_alignmask(
 315	struct crypto_ahash *tfm)
 316{
 317	return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
 318}
 319
 320/**
 321 * crypto_ahash_blocksize() - obtain block size for cipher
 322 * @tfm: cipher handle
 323 *
 324 * The block size for the message digest cipher referenced with the cipher
 325 * handle is returned.
 326 *
 327 * Return: block size of cipher
 328 */
 329static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
 330{
 331	return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
 332}
 333
 334static inline struct hash_alg_common *__crypto_hash_alg_common(
 335	struct crypto_alg *alg)
 336{
 337	return container_of(alg, struct hash_alg_common, base);
 338}
 339
 340static inline struct hash_alg_common *crypto_hash_alg_common(
 341	struct crypto_ahash *tfm)
 342{
 343	return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
 344}
 345
 346/**
 347 * crypto_ahash_digestsize() - obtain message digest size
 348 * @tfm: cipher handle
 349 *
 350 * The size for the message digest created by the message digest cipher
 351 * referenced with the cipher handle is returned.
 352 *
 353 *
 354 * Return: message digest size of cipher
 355 */
 356static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
 357{
 358	return crypto_hash_alg_common(tfm)->digestsize;
 359}
 360
 361/**
 362 * crypto_ahash_statesize() - obtain size of the ahash state
 363 * @tfm: cipher handle
 364 *
 365 * Return the size of the ahash state. With the crypto_ahash_export()
 366 * function, the caller can export the state into a buffer whose size is
 367 * defined with this function.
 368 *
 369 * Return: size of the ahash state
 370 */
 371static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
 372{
 373	return crypto_hash_alg_common(tfm)->statesize;
 374}
 375
 376static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
 377{
 378	return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
 379}
 380
 381static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
 382{
 383	crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
 384}
 385
 386static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
 387{
 388	crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
 389}
 390
 391/**
 392 * crypto_ahash_reqtfm() - obtain cipher handle from request
 393 * @req: asynchronous request handle that contains the reference to the ahash
 394 *	 cipher handle
 395 *
 396 * Return the ahash cipher handle that is registered with the asynchronous
 397 * request handle ahash_request.
 398 *
 399 * Return: ahash cipher handle
 400 */
 401static inline struct crypto_ahash *crypto_ahash_reqtfm(
 402	struct ahash_request *req)
 403{
 404	return __crypto_ahash_cast(req->base.tfm);
 405}
 406
 407/**
 408 * crypto_ahash_reqsize() - obtain size of the request data structure
 409 * @tfm: cipher handle
 410 *
 411 * Return: size of the request data
 412 */
 413static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
 414{
 415	return tfm->reqsize;
 416}
 417
 418static inline void *ahash_request_ctx(struct ahash_request *req)
 419{
 420	return req->__ctx;
 421}
 422
 423/**
 424 * crypto_ahash_setkey - set key for cipher handle
 425 * @tfm: cipher handle
 426 * @key: buffer holding the key
 427 * @keylen: length of the key in bytes
 428 *
 429 * The caller provided key is set for the ahash cipher. The cipher
 430 * handle must point to a keyed hash in order for this function to succeed.
 431 *
 432 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
 433 */
 434int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 435			unsigned int keylen);
 436
 437/**
 438 * crypto_ahash_finup() - update and finalize message digest
 439 * @req: reference to the ahash_request handle that holds all information
 440 *	 needed to perform the cipher operation
 441 *
 442 * This function is a "short-hand" for the function calls of
 443 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
 444 * meaning as discussed for those separate functions.
 445 *
 446 * Return: see crypto_ahash_final()
 447 */
 448int crypto_ahash_finup(struct ahash_request *req);
 449
 450/**
 451 * crypto_ahash_final() - calculate message digest
 452 * @req: reference to the ahash_request handle that holds all information
 453 *	 needed to perform the cipher operation
 454 *
 455 * Finalize the message digest operation and create the message digest
 456 * based on all data added to the cipher handle. The message digest is placed
 457 * into the output buffer registered with the ahash_request handle.
 458 *
 459 * Return:
 460 * 0		if the message digest was successfully calculated;
 461 * -EINPROGRESS	if data is fed into hardware (DMA) or queued for later;
 462 * -EBUSY	if queue is full and request should be resubmitted later;
 463 * other < 0	if an error occurred
 464 */
 465int crypto_ahash_final(struct ahash_request *req);
 466
 467/**
 468 * crypto_ahash_digest() - calculate message digest for a buffer
 469 * @req: reference to the ahash_request handle that holds all information
 470 *	 needed to perform the cipher operation
 471 *
 472 * This function is a "short-hand" for the function calls of crypto_ahash_init,
 473 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
 474 * meaning as discussed for those separate three functions.
 475 *
 476 * Return: see crypto_ahash_final()
 477 */
 478int crypto_ahash_digest(struct ahash_request *req);
 479
 480/**
 481 * crypto_ahash_export() - extract current message digest state
 482 * @req: reference to the ahash_request handle whose state is exported
 483 * @out: output buffer of sufficient size that can hold the hash state
 484 *
 485 * This function exports the hash state of the ahash_request handle into the
 486 * caller-allocated output buffer out which must have sufficient size (e.g. by
 487 * calling crypto_ahash_statesize()).
 488 *
 489 * Return: 0 if the export was successful; < 0 if an error occurred
 490 */
 491static inline int crypto_ahash_export(struct ahash_request *req, void *out)
 492{
 493	return crypto_ahash_reqtfm(req)->export(req, out);
 494}
 495
 496/**
 497 * crypto_ahash_import() - import message digest state
 498 * @req: reference to ahash_request handle the state is imported into
 499 * @in: buffer holding the state
 500 *
 501 * This function imports the hash state into the ahash_request handle from the
 502 * input buffer. That buffer should have been generated with the
 503 * crypto_ahash_export function.
 504 *
 505 * Return: 0 if the import was successful; < 0 if an error occurred
 506 */
 507static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
 508{
 509	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 510
 511	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 512		return -ENOKEY;
 513
 514	return tfm->import(req, in);
 515}
 516
 517/**
 518 * crypto_ahash_init() - (re)initialize message digest handle
 519 * @req: ahash_request handle that already is initialized with all necessary
 520 *	 data using the ahash_request_* API functions
 521 *
 522 * The call (re-)initializes the message digest referenced by the ahash_request
 523 * handle. Any potentially existing state created by previous operations is
 524 * discarded.
 525 *
 526 * Return: see crypto_ahash_final()
 527 */
 528static inline int crypto_ahash_init(struct ahash_request *req)
 529{
 530	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 531
 532	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 533		return -ENOKEY;
 534
 535	return tfm->init(req);
 536}
 537
 538/**
 539 * crypto_ahash_update() - add data to message digest for processing
 540 * @req: ahash_request handle that was previously initialized with the
 541 *	 crypto_ahash_init call.
 542 *
 543 * Updates the message digest state of the &ahash_request handle. The input data
 544 * is pointed to by the scatter/gather list registered in the &ahash_request
 545 * handle
 546 *
 547 * Return: see crypto_ahash_final()
 548 */
 549static inline int crypto_ahash_update(struct ahash_request *req)
 550{
 551	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 552	struct crypto_alg *alg = tfm->base.__crt_alg;
 553	unsigned int nbytes = req->nbytes;
 554	int ret;
 555
 556	crypto_stats_get(alg);
 557	ret = crypto_ahash_reqtfm(req)->update(req);
 558	crypto_stats_ahash_update(nbytes, ret, alg);
 559	return ret;
 560}
 561
 562/**
 563 * DOC: Asynchronous Hash Request Handle
 564 *
 565 * The &ahash_request data structure contains all pointers to data
 566 * required for the asynchronous cipher operation. This includes the cipher
 567 * handle (which can be used by multiple &ahash_request instances), pointer
 568 * to plaintext and the message digest output buffer, asynchronous callback
 569 * function, etc. It acts as a handle to the ahash_request_* API calls in a
 570 * similar way as ahash handle to the crypto_ahash_* API calls.
 571 */
 572
 573/**
 574 * ahash_request_set_tfm() - update cipher handle reference in request
 575 * @req: request handle to be modified
 576 * @tfm: cipher handle that shall be added to the request handle
 577 *
 578 * Allow the caller to replace the existing ahash handle in the request
 579 * data structure with a different one.
 580 */
 581static inline void ahash_request_set_tfm(struct ahash_request *req,
 582					 struct crypto_ahash *tfm)
 583{
 584	req->base.tfm = crypto_ahash_tfm(tfm);
 585}
 586
 587/**
 588 * ahash_request_alloc() - allocate request data structure
 589 * @tfm: cipher handle to be registered with the request
 590 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
 591 *
 592 * Allocate the request data structure that must be used with the ahash
 593 * message digest API calls. During
 594 * the allocation, the provided ahash handle
 595 * is registered in the request data structure.
 596 *
 597 * Return: allocated request handle in case of success, or NULL if out of memory
 598 */
 599static inline struct ahash_request *ahash_request_alloc(
 600	struct crypto_ahash *tfm, gfp_t gfp)
 601{
 602	struct ahash_request *req;
 603
 604	req = kmalloc(sizeof(struct ahash_request) +
 605		      crypto_ahash_reqsize(tfm), gfp);
 606
 607	if (likely(req))
 608		ahash_request_set_tfm(req, tfm);
 609
 610	return req;
 611}
 612
 613/**
 614 * ahash_request_free() - zeroize and free the request data structure
 615 * @req: request data structure cipher handle to be freed
 616 */
 617static inline void ahash_request_free(struct ahash_request *req)
 618{
 619	kfree_sensitive(req);
 620}
 621
 622static inline void ahash_request_zero(struct ahash_request *req)
 623{
 624	memzero_explicit(req, sizeof(*req) +
 625			      crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
 626}
 627
 628static inline struct ahash_request *ahash_request_cast(
 629	struct crypto_async_request *req)
 630{
 631	return container_of(req, struct ahash_request, base);
 632}
 633
 634/**
 635 * ahash_request_set_callback() - set asynchronous callback function
 636 * @req: request handle
 637 * @flags: specify zero or an ORing of the flags
 638 *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
 639 *	   increase the wait queue beyond the initial maximum size;
 640 *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
 641 * @compl: callback function pointer to be registered with the request handle
 642 * @data: The data pointer refers to memory that is not used by the kernel
 643 *	  crypto API, but provided to the callback function for it to use. Here,
 644 *	  the caller can provide a reference to memory the callback function can
 645 *	  operate on. As the callback function is invoked asynchronously to the
 646 *	  related functionality, it may need to access data structures of the
 647 *	  related functionality which can be referenced using this pointer. The
 648 *	  callback function can access the memory via the "data" field in the
 649 *	  &crypto_async_request data structure provided to the callback function.
 650 *
 651 * This function allows setting the callback function that is triggered once
 652 * the cipher operation completes.
 653 *
 654 * The callback function is registered with the &ahash_request handle and
 655 * must comply with the following template::
 656 *
 657 *	void callback_function(struct crypto_async_request *req, int error)
 658 */
 659static inline void ahash_request_set_callback(struct ahash_request *req,
 660					      u32 flags,
 661					      crypto_completion_t compl,
 662					      void *data)
 663{
 664	req->base.complete = compl;
 665	req->base.data = data;
 666	req->base.flags = flags;
 667}
 668
 669/**
 670 * ahash_request_set_crypt() - set data buffers
 671 * @req: ahash_request handle to be updated
 672 * @src: source scatter/gather list
 673 * @result: buffer that is filled with the message digest -- the caller must
 674 *	    ensure that the buffer has sufficient space by, for example, calling
 675 *	    crypto_ahash_digestsize()
 676 * @nbytes: number of bytes to process from the source scatter/gather list
 677 *
 678 * By using this call, the caller references the source scatter/gather list.
 679 * The source scatter/gather list points to the data the message digest is to
 680 * be calculated for.
 681 */
 682static inline void ahash_request_set_crypt(struct ahash_request *req,
 683					   struct scatterlist *src, u8 *result,
 684					   unsigned int nbytes)
 685{
 686	req->src = src;
 687	req->nbytes = nbytes;
 688	req->result = result;
 689}
 690
 691/**
 692 * DOC: Synchronous Message Digest API
 693 *
 694 * The synchronous message digest API is used with the ciphers of type
 695 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
 696 *
 697 * The message digest API is able to maintain state information for the
 698 * caller.
 699 *
 700 * The synchronous message digest API can store user-related context in its
 701 * shash_desc request data structure.
 702 */
 703
 704/**
 705 * crypto_alloc_shash() - allocate message digest handle
 706 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
 707 *	      message digest cipher
 708 * @type: specifies the type of the cipher
 709 * @mask: specifies the mask for the cipher
 710 *
 711 * Allocate a cipher handle for a message digest. The returned &struct
 712 * crypto_shash is the cipher handle that is required for any subsequent
 713 * API invocation for that message digest.
 714 *
 715 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
 716 *	   of an error, PTR_ERR() returns the error code.
 717 */
 718struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
 719					u32 mask);
 720
 
 
 721int crypto_has_shash(const char *alg_name, u32 type, u32 mask);
 722
 723static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
 724{
 725	return &tfm->base;
 726}
 727
 728/**
 729 * crypto_free_shash() - zeroize and free the message digest handle
 730 * @tfm: cipher handle to be freed
 731 *
 732 * If @tfm is a NULL or error pointer, this function does nothing.
 733 */
 734static inline void crypto_free_shash(struct crypto_shash *tfm)
 735{
 736	crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
 737}
 738
 739static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
 740{
 741	return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
 742}
 743
 744static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
 745{
 746	return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
 747}
 748
 749static inline unsigned int crypto_shash_alignmask(
 750	struct crypto_shash *tfm)
 751{
 752	return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
 753}
 754
 755/**
 756 * crypto_shash_blocksize() - obtain block size for cipher
 757 * @tfm: cipher handle
 758 *
 759 * The block size for the message digest cipher referenced with the cipher
 760 * handle is returned.
 761 *
 762 * Return: block size of cipher
 763 */
 764static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
 765{
 766	return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
 767}
 768
 769static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
 770{
 771	return container_of(alg, struct shash_alg, base);
 772}
 773
 774static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
 775{
 776	return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
 777}
 778
 779/**
 780 * crypto_shash_digestsize() - obtain message digest size
 781 * @tfm: cipher handle
 782 *
 783 * The size for the message digest created by the message digest cipher
 784 * referenced with the cipher handle is returned.
 785 *
 786 * Return: digest size of cipher
 787 */
 788static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
 789{
 790	return crypto_shash_alg(tfm)->digestsize;
 791}
 792
 793static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
 794{
 795	return crypto_shash_alg(tfm)->statesize;
 796}
 797
 798static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
 799{
 800	return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
 801}
 802
 803static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
 804{
 805	crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
 806}
 807
 808static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
 809{
 810	crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
 811}
 812
 813/**
 814 * crypto_shash_descsize() - obtain the operational state size
 815 * @tfm: cipher handle
 816 *
 817 * The size of the operational state the cipher needs during operation is
 818 * returned for the hash referenced with the cipher handle. This size is
 819 * required to calculate the memory requirements to allow the caller allocating
 820 * sufficient memory for operational state.
 821 *
 822 * The operational state is defined with struct shash_desc where the size of
 823 * that data structure is to be calculated as
 824 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
 825 *
 826 * Return: size of the operational state
 827 */
 828static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
 829{
 830	return tfm->descsize;
 831}
 832
 833static inline void *shash_desc_ctx(struct shash_desc *desc)
 834{
 835	return desc->__ctx;
 836}
 837
 838/**
 839 * crypto_shash_setkey() - set key for message digest
 840 * @tfm: cipher handle
 841 * @key: buffer holding the key
 842 * @keylen: length of the key in bytes
 843 *
 844 * The caller provided key is set for the keyed message digest cipher. The
 845 * cipher handle must point to a keyed message digest cipher in order for this
 846 * function to succeed.
 847 *
 848 * Context: Any context.
 849 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
 850 */
 851int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
 852			unsigned int keylen);
 853
 854/**
 855 * crypto_shash_digest() - calculate message digest for buffer
 856 * @desc: see crypto_shash_final()
 857 * @data: see crypto_shash_update()
 858 * @len: see crypto_shash_update()
 859 * @out: see crypto_shash_final()
 860 *
 861 * This function is a "short-hand" for the function calls of crypto_shash_init,
 862 * crypto_shash_update and crypto_shash_final. The parameters have the same
 863 * meaning as discussed for those separate three functions.
 864 *
 865 * Context: Any context.
 866 * Return: 0 if the message digest creation was successful; < 0 if an error
 867 *	   occurred
 868 */
 869int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
 870			unsigned int len, u8 *out);
 871
 872/**
 873 * crypto_shash_tfm_digest() - calculate message digest for buffer
 874 * @tfm: hash transformation object
 875 * @data: see crypto_shash_update()
 876 * @len: see crypto_shash_update()
 877 * @out: see crypto_shash_final()
 878 *
 879 * This is a simplified version of crypto_shash_digest() for users who don't
 880 * want to allocate their own hash descriptor (shash_desc).  Instead,
 881 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash)
 882 * directly, and it allocates a hash descriptor on the stack internally.
 883 * Note that this stack allocation may be fairly large.
 884 *
 885 * Context: Any context.
 886 * Return: 0 on success; < 0 if an error occurred.
 887 */
 888int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
 889			    unsigned int len, u8 *out);
 890
 891/**
 892 * crypto_shash_export() - extract operational state for message digest
 893 * @desc: reference to the operational state handle whose state is exported
 894 * @out: output buffer of sufficient size that can hold the hash state
 895 *
 896 * This function exports the hash state of the operational state handle into the
 897 * caller-allocated output buffer out which must have sufficient size (e.g. by
 898 * calling crypto_shash_descsize).
 899 *
 900 * Context: Any context.
 901 * Return: 0 if the export creation was successful; < 0 if an error occurred
 902 */
 903static inline int crypto_shash_export(struct shash_desc *desc, void *out)
 904{
 905	return crypto_shash_alg(desc->tfm)->export(desc, out);
 906}
 907
 908/**
 909 * crypto_shash_import() - import operational state
 910 * @desc: reference to the operational state handle the state imported into
 911 * @in: buffer holding the state
 912 *
 913 * This function imports the hash state into the operational state handle from
 914 * the input buffer. That buffer should have been generated with the
 915 * crypto_ahash_export function.
 916 *
 917 * Context: Any context.
 918 * Return: 0 if the import was successful; < 0 if an error occurred
 919 */
 920static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
 921{
 922	struct crypto_shash *tfm = desc->tfm;
 923
 924	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 925		return -ENOKEY;
 926
 927	return crypto_shash_alg(tfm)->import(desc, in);
 928}
 929
 930/**
 931 * crypto_shash_init() - (re)initialize message digest
 932 * @desc: operational state handle that is already filled
 933 *
 934 * The call (re-)initializes the message digest referenced by the
 935 * operational state handle. Any potentially existing state created by
 936 * previous operations is discarded.
 937 *
 938 * Context: Any context.
 939 * Return: 0 if the message digest initialization was successful; < 0 if an
 940 *	   error occurred
 941 */
 942static inline int crypto_shash_init(struct shash_desc *desc)
 943{
 944	struct crypto_shash *tfm = desc->tfm;
 945
 946	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 947		return -ENOKEY;
 948
 949	return crypto_shash_alg(tfm)->init(desc);
 950}
 951
 952/**
 953 * crypto_shash_update() - add data to message digest for processing
 954 * @desc: operational state handle that is already initialized
 955 * @data: input data to be added to the message digest
 956 * @len: length of the input data
 957 *
 958 * Updates the message digest state of the operational state handle.
 959 *
 960 * Context: Any context.
 961 * Return: 0 if the message digest update was successful; < 0 if an error
 962 *	   occurred
 963 */
 964int crypto_shash_update(struct shash_desc *desc, const u8 *data,
 965			unsigned int len);
 966
 967/**
 968 * crypto_shash_final() - calculate message digest
 969 * @desc: operational state handle that is already filled with data
 970 * @out: output buffer filled with the message digest
 971 *
 972 * Finalize the message digest operation and create the message digest
 973 * based on all data added to the cipher handle. The message digest is placed
 974 * into the output buffer. The caller must ensure that the output buffer is
 975 * large enough by using crypto_shash_digestsize.
 976 *
 977 * Context: Any context.
 978 * Return: 0 if the message digest creation was successful; < 0 if an error
 979 *	   occurred
 980 */
 981int crypto_shash_final(struct shash_desc *desc, u8 *out);
 982
 983/**
 984 * crypto_shash_finup() - calculate message digest of buffer
 985 * @desc: see crypto_shash_final()
 986 * @data: see crypto_shash_update()
 987 * @len: see crypto_shash_update()
 988 * @out: see crypto_shash_final()
 989 *
 990 * This function is a "short-hand" for the function calls of
 991 * crypto_shash_update and crypto_shash_final. The parameters have the same
 992 * meaning as discussed for those separate functions.
 993 *
 994 * Context: Any context.
 995 * Return: 0 if the message digest creation was successful; < 0 if an error
 996 *	   occurred
 997 */
 998int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
 999		       unsigned int len, u8 *out);
1000
1001static inline void shash_desc_zero(struct shash_desc *desc)
1002{
1003	memzero_explicit(desc,
1004			 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
1005}
1006
1007#endif	/* _CRYPTO_HASH_H */