2 * Hash: Hash algorithms under the crypto API
4 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
13 #ifndef _CRYPTO_HASH_H
14 #define _CRYPTO_HASH_H
16 #include <linux/crypto.h>
17 #include <linux/string.h>
22 * DOC: Message Digest Algorithm Definitions
24 * These data structures define modular message digest algorithm
25 * implementations, managed via crypto_register_ahash(),
26 * crypto_register_shash(), crypto_unregister_ahash() and
27 * crypto_unregister_shash().
31 * struct hash_alg_common - define properties of message digest
32 * @digestsize: Size of the result of the transformation. A buffer of this size
33 * must be available to the @final and @finup calls, so they can
34 * store the resulting hash into it. For various predefined sizes,
35 * search include/crypto/ using
36 * git grep _DIGEST_SIZE include/crypto.
37 * @statesize: Size of the block for partial state of the transformation. A
38 * buffer of this size must be passed to the @export function as it
39 * will save the partial state of the transformation into it. On the
40 * other side, the @import function will load the state from a
41 * buffer of this size as well.
42 * @base: Start of data structure of cipher algorithm. The common data
43 * structure of crypto_alg contains information common to all ciphers.
44 * The hash_alg_common data structure now adds the hash-specific
47 struct hash_alg_common {
48 unsigned int digestsize;
49 unsigned int statesize;
51 struct crypto_alg base;
54 struct ahash_request {
55 struct crypto_async_request base;
58 struct scatterlist *src;
61 /* This field may only be used by the ahash API code. */
64 void *__ctx[] CRYPTO_MINALIGN_ATTR;
67 #define AHASH_REQUEST_ON_STACK(name, ahash) \
68 char __##name##_desc[sizeof(struct ahash_request) + \
69 crypto_ahash_reqsize(ahash)] CRYPTO_MINALIGN_ATTR; \
70 struct ahash_request *name = (void *)__##name##_desc
73 * struct ahash_alg - asynchronous message digest definition
74 * @init: Initialize the transformation context. Intended only to initialize the
75 * state of the HASH transformation at the beginning. This shall fill in
76 * the internal structures used during the entire duration of the whole
77 * transformation. No data processing happens at this point.
78 * @update: Push a chunk of data into the driver for transformation. This
79 * function actually pushes blocks of data from upper layers into the
80 * driver, which then passes those to the hardware as seen fit. This
81 * function must not finalize the HASH transformation by calculating the
82 * final message digest as this only adds more data into the
83 * transformation. This function shall not modify the transformation
84 * context, as this function may be called in parallel with the same
85 * transformation object. Data processing can happen synchronously
86 * [SHASH] or asynchronously [AHASH] at this point.
87 * @final: Retrieve result from the driver. This function finalizes the
88 * transformation and retrieves the resulting hash from the driver and
89 * pushes it back to upper layers. No data processing happens at this
91 * @finup: Combination of @update and @final. This function is effectively a
92 * combination of @update and @final calls issued in sequence. As some
93 * hardware cannot do @update and @final separately, this callback was
94 * added to allow such hardware to be used at least by IPsec. Data
95 * processing can happen synchronously [SHASH] or asynchronously [AHASH]
97 * @digest: Combination of @init and @update and @final. This function
98 * effectively behaves as the entire chain of operations, @init,
99 * @update and @final issued in sequence. Just like @finup, this was
100 * added for hardware which cannot do even the @finup, but can only do
101 * the whole transformation in one run. Data processing can happen
102 * synchronously [SHASH] or asynchronously [AHASH] at this point.
103 * @setkey: Set optional key used by the hashing algorithm. Intended to push
104 * optional key used by the hashing algorithm from upper layers into
105 * the driver. This function can store the key in the transformation
106 * context or can outright program it into the hardware. In the former
107 * case, one must be careful to program the key into the hardware at
108 * appropriate time and one must be careful that .setkey() can be
109 * called multiple times during the existence of the transformation
110 * object. Not all hashing algorithms do implement this function as it
111 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
112 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
113 * this function. This function must be called before any other of the
114 * @init, @update, @final, @finup, @digest is called. No data
115 * processing happens at this point.
116 * @export: Export partial state of the transformation. This function dumps the
117 * entire state of the ongoing transformation into a provided block of
118 * data so it can be @import 'ed back later on. This is useful in case
119 * you want to save partial result of the transformation after
120 * processing certain amount of data and reload this partial result
121 * multiple times later on for multiple re-use. No data processing
122 * happens at this point.
123 * @import: Import partial state of the transformation. This function loads the
124 * entire state of the ongoing transformation from a provided block of
125 * data so the transformation can continue from this point onward. No
126 * data processing happens at this point.
127 * @halg: see struct hash_alg_common
130 int (*init)(struct ahash_request *req);
131 int (*update)(struct ahash_request *req);
132 int (*final)(struct ahash_request *req);
133 int (*finup)(struct ahash_request *req);
134 int (*digest)(struct ahash_request *req);
135 int (*export)(struct ahash_request *req, void *out);
136 int (*import)(struct ahash_request *req, const void *in);
137 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
138 unsigned int keylen);
140 struct hash_alg_common halg;
144 struct crypto_shash *tfm;
147 void *__ctx[] CRYPTO_MINALIGN_ATTR;
150 #define SHASH_DESC_ON_STACK(shash, ctx) \
151 char __##shash##_desc[sizeof(struct shash_desc) + \
152 crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
153 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
156 * struct shash_alg - synchronous message digest definition
157 * @init: see struct ahash_alg
158 * @update: see struct ahash_alg
159 * @final: see struct ahash_alg
160 * @finup: see struct ahash_alg
161 * @digest: see struct ahash_alg
162 * @export: see struct ahash_alg
163 * @import: see struct ahash_alg
164 * @setkey: see struct ahash_alg
165 * @digestsize: see struct ahash_alg
166 * @statesize: see struct ahash_alg
167 * @descsize: Size of the operational state for the message digest. This state
168 * size is the memory size that needs to be allocated for
170 * @base: internally used
173 int (*init)(struct shash_desc *desc);
174 int (*update)(struct shash_desc *desc, const u8 *data,
176 int (*final)(struct shash_desc *desc, u8 *out);
177 int (*finup)(struct shash_desc *desc, const u8 *data,
178 unsigned int len, u8 *out);
179 int (*digest)(struct shash_desc *desc, const u8 *data,
180 unsigned int len, u8 *out);
181 int (*export)(struct shash_desc *desc, void *out);
182 int (*import)(struct shash_desc *desc, const void *in);
183 int (*setkey)(struct crypto_shash *tfm, const u8 *key,
184 unsigned int keylen);
186 unsigned int descsize;
188 /* These fields must match hash_alg_common. */
189 unsigned int digestsize
190 __attribute__ ((aligned(__alignof__(struct hash_alg_common))));
191 unsigned int statesize;
193 struct crypto_alg base;
196 struct crypto_ahash {
197 int (*init)(struct ahash_request *req);
198 int (*update)(struct ahash_request *req);
199 int (*final)(struct ahash_request *req);
200 int (*finup)(struct ahash_request *req);
201 int (*digest)(struct ahash_request *req);
202 int (*export)(struct ahash_request *req, void *out);
203 int (*import)(struct ahash_request *req, const void *in);
204 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
205 unsigned int keylen);
207 unsigned int reqsize;
208 struct crypto_tfm base;
211 struct crypto_shash {
212 unsigned int descsize;
213 struct crypto_tfm base;
217 * DOC: Asynchronous Message Digest API
219 * The asynchronous message digest API is used with the ciphers of type
220 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
222 * The asynchronous cipher operation discussion provided for the
223 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well.
226 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
228 return container_of(tfm, struct crypto_ahash, base);
232 * crypto_alloc_ahash() - allocate ahash cipher handle
233 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
235 * @type: specifies the type of the cipher
236 * @mask: specifies the mask for the cipher
238 * Allocate a cipher handle for an ahash. The returned struct
239 * crypto_ahash is the cipher handle that is required for any subsequent
240 * API invocation for that ahash.
242 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
243 * of an error, PTR_ERR() returns the error code.
245 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
248 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
254 * crypto_free_ahash() - zeroize and free the ahash handle
255 * @tfm: cipher handle to be freed
257 * If @tfm is a NULL or error pointer, this function does nothing.
259 static inline void crypto_free_ahash(struct crypto_ahash *tfm)
261 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
265 * crypto_has_ahash() - Search for the availability of an ahash.
266 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
268 * @type: specifies the type of the ahash
269 * @mask: specifies the mask for the ahash
271 * Return: true when the ahash is known to the kernel crypto API; false
274 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
276 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
278 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
281 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
283 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
286 static inline unsigned int crypto_ahash_alignmask(
287 struct crypto_ahash *tfm)
289 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
293 * crypto_ahash_blocksize() - obtain block size for cipher
294 * @tfm: cipher handle
296 * The block size for the message digest cipher referenced with the cipher
297 * handle is returned.
299 * Return: block size of cipher
301 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
303 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
306 static inline struct hash_alg_common *__crypto_hash_alg_common(
307 struct crypto_alg *alg)
309 return container_of(alg, struct hash_alg_common, base);
312 static inline struct hash_alg_common *crypto_hash_alg_common(
313 struct crypto_ahash *tfm)
315 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
319 * crypto_ahash_digestsize() - obtain message digest size
320 * @tfm: cipher handle
322 * The size for the message digest created by the message digest cipher
323 * referenced with the cipher handle is returned.
326 * Return: message digest size of cipher
328 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
330 return crypto_hash_alg_common(tfm)->digestsize;
334 * crypto_ahash_statesize() - obtain size of the ahash state
335 * @tfm: cipher handle
337 * Return the size of the ahash state. With the crypto_ahash_export()
338 * function, the caller can export the state into a buffer whose size is
339 * defined with this function.
341 * Return: size of the ahash state
343 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
345 return crypto_hash_alg_common(tfm)->statesize;
348 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
350 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
353 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
355 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
358 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
360 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
364 * crypto_ahash_reqtfm() - obtain cipher handle from request
365 * @req: asynchronous request handle that contains the reference to the ahash
368 * Return the ahash cipher handle that is registered with the asynchronous
369 * request handle ahash_request.
371 * Return: ahash cipher handle
373 static inline struct crypto_ahash *crypto_ahash_reqtfm(
374 struct ahash_request *req)
376 return __crypto_ahash_cast(req->base.tfm);
380 * crypto_ahash_reqsize() - obtain size of the request data structure
381 * @tfm: cipher handle
383 * Return: size of the request data
385 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
390 static inline void *ahash_request_ctx(struct ahash_request *req)
396 * crypto_ahash_setkey - set key for cipher handle
397 * @tfm: cipher handle
398 * @key: buffer holding the key
399 * @keylen: length of the key in bytes
401 * The caller provided key is set for the ahash cipher. The cipher
402 * handle must point to a keyed hash in order for this function to succeed.
404 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
406 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
407 unsigned int keylen);
410 * crypto_ahash_finup() - update and finalize message digest
411 * @req: reference to the ahash_request handle that holds all information
412 * needed to perform the cipher operation
414 * This function is a "short-hand" for the function calls of
415 * crypto_ahash_update and crypto_shash_final. The parameters have the same
416 * meaning as discussed for those separate functions.
418 * Return: 0 if the message digest creation was successful; < 0 if an error
421 int crypto_ahash_finup(struct ahash_request *req);
424 * crypto_ahash_final() - calculate message digest
425 * @req: reference to the ahash_request handle that holds all information
426 * needed to perform the cipher operation
428 * Finalize the message digest operation and create the message digest
429 * based on all data added to the cipher handle. The message digest is placed
430 * into the output buffer registered with the ahash_request handle.
432 * Return: 0 if the message digest creation was successful; < 0 if an error
435 int crypto_ahash_final(struct ahash_request *req);
438 * crypto_ahash_digest() - calculate message digest for a buffer
439 * @req: reference to the ahash_request handle that holds all information
440 * needed to perform the cipher operation
442 * This function is a "short-hand" for the function calls of crypto_ahash_init,
443 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
444 * meaning as discussed for those separate three functions.
446 * Return: 0 if the message digest creation was successful; < 0 if an error
449 int crypto_ahash_digest(struct ahash_request *req);
452 * crypto_ahash_export() - extract current message digest state
453 * @req: reference to the ahash_request handle whose state is exported
454 * @out: output buffer of sufficient size that can hold the hash state
456 * This function exports the hash state of the ahash_request handle into the
457 * caller-allocated output buffer out which must have sufficient size (e.g. by
458 * calling crypto_ahash_statesize()).
460 * Return: 0 if the export was successful; < 0 if an error occurred
462 static inline int crypto_ahash_export(struct ahash_request *req, void *out)
464 return crypto_ahash_reqtfm(req)->export(req, out);
468 * crypto_ahash_import() - import message digest state
469 * @req: reference to ahash_request handle the state is imported into
470 * @in: buffer holding the state
472 * This function imports the hash state into the ahash_request handle from the
473 * input buffer. That buffer should have been generated with the
474 * crypto_ahash_export function.
476 * Return: 0 if the import was successful; < 0 if an error occurred
478 static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
480 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
482 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
485 return tfm->import(req, in);
489 * crypto_ahash_init() - (re)initialize message digest handle
490 * @req: ahash_request handle that already is initialized with all necessary
491 * data using the ahash_request_* API functions
493 * The call (re-)initializes the message digest referenced by the ahash_request
494 * handle. Any potentially existing state created by previous operations is
497 * Return: 0 if the message digest initialization was successful; < 0 if an
500 static inline int crypto_ahash_init(struct ahash_request *req)
502 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
504 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
507 return tfm->init(req);
511 * crypto_ahash_update() - add data to message digest for processing
512 * @req: ahash_request handle that was previously initialized with the
513 * crypto_ahash_init call.
515 * Updates the message digest state of the &ahash_request handle. The input data
516 * is pointed to by the scatter/gather list registered in the &ahash_request
519 * Return: 0 if the message digest update was successful; < 0 if an error
522 static inline int crypto_ahash_update(struct ahash_request *req)
524 return crypto_ahash_reqtfm(req)->update(req);
528 * DOC: Asynchronous Hash Request Handle
530 * The &ahash_request data structure contains all pointers to data
531 * required for the asynchronous cipher operation. This includes the cipher
532 * handle (which can be used by multiple &ahash_request instances), pointer
533 * to plaintext and the message digest output buffer, asynchronous callback
534 * function, etc. It acts as a handle to the ahash_request_* API calls in a
535 * similar way as ahash handle to the crypto_ahash_* API calls.
539 * ahash_request_set_tfm() - update cipher handle reference in request
540 * @req: request handle to be modified
541 * @tfm: cipher handle that shall be added to the request handle
543 * Allow the caller to replace the existing ahash handle in the request
544 * data structure with a different one.
546 static inline void ahash_request_set_tfm(struct ahash_request *req,
547 struct crypto_ahash *tfm)
549 req->base.tfm = crypto_ahash_tfm(tfm);
553 * ahash_request_alloc() - allocate request data structure
554 * @tfm: cipher handle to be registered with the request
555 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
557 * Allocate the request data structure that must be used with the ahash
558 * message digest API calls. During
559 * the allocation, the provided ahash handle
560 * is registered in the request data structure.
562 * Return: allocated request handle in case of success, or NULL if out of memory
564 static inline struct ahash_request *ahash_request_alloc(
565 struct crypto_ahash *tfm, gfp_t gfp)
567 struct ahash_request *req;
569 req = kmalloc(sizeof(struct ahash_request) +
570 crypto_ahash_reqsize(tfm), gfp);
573 ahash_request_set_tfm(req, tfm);
579 * ahash_request_free() - zeroize and free the request data structure
580 * @req: request data structure cipher handle to be freed
582 static inline void ahash_request_free(struct ahash_request *req)
587 static inline void ahash_request_zero(struct ahash_request *req)
589 memzero_explicit(req, sizeof(*req) +
590 crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
593 static inline struct ahash_request *ahash_request_cast(
594 struct crypto_async_request *req)
596 return container_of(req, struct ahash_request, base);
600 * ahash_request_set_callback() - set asynchronous callback function
601 * @req: request handle
602 * @flags: specify zero or an ORing of the flags
603 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
604 * increase the wait queue beyond the initial maximum size;
605 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
606 * @compl: callback function pointer to be registered with the request handle
607 * @data: The data pointer refers to memory that is not used by the kernel
608 * crypto API, but provided to the callback function for it to use. Here,
609 * the caller can provide a reference to memory the callback function can
610 * operate on. As the callback function is invoked asynchronously to the
611 * related functionality, it may need to access data structures of the
612 * related functionality which can be referenced using this pointer. The
613 * callback function can access the memory via the "data" field in the
614 * &crypto_async_request data structure provided to the callback function.
616 * This function allows setting the callback function that is triggered once
617 * the cipher operation completes.
619 * The callback function is registered with the &ahash_request handle and
620 * must comply with the following template::
622 * void callback_function(struct crypto_async_request *req, int error)
624 static inline void ahash_request_set_callback(struct ahash_request *req,
626 crypto_completion_t compl,
629 req->base.complete = compl;
630 req->base.data = data;
631 req->base.flags = flags;
635 * ahash_request_set_crypt() - set data buffers
636 * @req: ahash_request handle to be updated
637 * @src: source scatter/gather list
638 * @result: buffer that is filled with the message digest -- the caller must
639 * ensure that the buffer has sufficient space by, for example, calling
640 * crypto_ahash_digestsize()
641 * @nbytes: number of bytes to process from the source scatter/gather list
643 * By using this call, the caller references the source scatter/gather list.
644 * The source scatter/gather list points to the data the message digest is to
647 static inline void ahash_request_set_crypt(struct ahash_request *req,
648 struct scatterlist *src, u8 *result,
652 req->nbytes = nbytes;
653 req->result = result;
657 * DOC: Synchronous Message Digest API
659 * The synchronous message digest API is used with the ciphers of type
660 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
662 * The message digest API is able to maintain state information for the
665 * The synchronous message digest API can store user-related context in in its
666 * shash_desc request data structure.
670 * crypto_alloc_shash() - allocate message digest handle
671 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
672 * message digest cipher
673 * @type: specifies the type of the cipher
674 * @mask: specifies the mask for the cipher
676 * Allocate a cipher handle for a message digest. The returned &struct
677 * crypto_shash is the cipher handle that is required for any subsequent
678 * API invocation for that message digest.
680 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
681 * of an error, PTR_ERR() returns the error code.
683 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
686 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
692 * crypto_free_shash() - zeroize and free the message digest handle
693 * @tfm: cipher handle to be freed
695 * If @tfm is a NULL or error pointer, this function does nothing.
697 static inline void crypto_free_shash(struct crypto_shash *tfm)
699 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
702 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
704 return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
707 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
709 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
712 static inline unsigned int crypto_shash_alignmask(
713 struct crypto_shash *tfm)
715 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
719 * crypto_shash_blocksize() - obtain block size for cipher
720 * @tfm: cipher handle
722 * The block size for the message digest cipher referenced with the cipher
723 * handle is returned.
725 * Return: block size of cipher
727 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
729 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
732 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
734 return container_of(alg, struct shash_alg, base);
737 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
739 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
743 * crypto_shash_digestsize() - obtain message digest size
744 * @tfm: cipher handle
746 * The size for the message digest created by the message digest cipher
747 * referenced with the cipher handle is returned.
749 * Return: digest size of cipher
751 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
753 return crypto_shash_alg(tfm)->digestsize;
756 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
758 return crypto_shash_alg(tfm)->statesize;
761 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
763 return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
766 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
768 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
771 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
773 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
777 * crypto_shash_descsize() - obtain the operational state size
778 * @tfm: cipher handle
780 * The size of the operational state the cipher needs during operation is
781 * returned for the hash referenced with the cipher handle. This size is
782 * required to calculate the memory requirements to allow the caller allocating
783 * sufficient memory for operational state.
785 * The operational state is defined with struct shash_desc where the size of
786 * that data structure is to be calculated as
787 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
789 * Return: size of the operational state
791 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
793 return tfm->descsize;
796 static inline void *shash_desc_ctx(struct shash_desc *desc)
802 * crypto_shash_setkey() - set key for message digest
803 * @tfm: cipher handle
804 * @key: buffer holding the key
805 * @keylen: length of the key in bytes
807 * The caller provided key is set for the keyed message digest cipher. The
808 * cipher handle must point to a keyed message digest cipher in order for this
809 * function to succeed.
811 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
813 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
814 unsigned int keylen);
817 * crypto_shash_digest() - calculate message digest for buffer
818 * @desc: see crypto_shash_final()
819 * @data: see crypto_shash_update()
820 * @len: see crypto_shash_update()
821 * @out: see crypto_shash_final()
823 * This function is a "short-hand" for the function calls of crypto_shash_init,
824 * crypto_shash_update and crypto_shash_final. The parameters have the same
825 * meaning as discussed for those separate three functions.
827 * Return: 0 if the message digest creation was successful; < 0 if an error
830 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
831 unsigned int len, u8 *out);
834 * crypto_shash_export() - extract operational state for message digest
835 * @desc: reference to the operational state handle whose state is exported
836 * @out: output buffer of sufficient size that can hold the hash state
838 * This function exports the hash state of the operational state handle into the
839 * caller-allocated output buffer out which must have sufficient size (e.g. by
840 * calling crypto_shash_descsize).
842 * Return: 0 if the export creation was successful; < 0 if an error occurred
844 static inline int crypto_shash_export(struct shash_desc *desc, void *out)
846 return crypto_shash_alg(desc->tfm)->export(desc, out);
850 * crypto_shash_import() - import operational state
851 * @desc: reference to the operational state handle the state imported into
852 * @in: buffer holding the state
854 * This function imports the hash state into the operational state handle from
855 * the input buffer. That buffer should have been generated with the
856 * crypto_ahash_export function.
858 * Return: 0 if the import was successful; < 0 if an error occurred
860 static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
862 struct crypto_shash *tfm = desc->tfm;
864 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
867 return crypto_shash_alg(tfm)->import(desc, in);
871 * crypto_shash_init() - (re)initialize message digest
872 * @desc: operational state handle that is already filled
874 * The call (re-)initializes the message digest referenced by the
875 * operational state handle. Any potentially existing state created by
876 * previous operations is discarded.
878 * Return: 0 if the message digest initialization was successful; < 0 if an
881 static inline int crypto_shash_init(struct shash_desc *desc)
883 struct crypto_shash *tfm = desc->tfm;
885 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
888 return crypto_shash_alg(tfm)->init(desc);
892 * crypto_shash_update() - add data to message digest for processing
893 * @desc: operational state handle that is already initialized
894 * @data: input data to be added to the message digest
895 * @len: length of the input data
897 * Updates the message digest state of the operational state handle.
899 * Return: 0 if the message digest update was successful; < 0 if an error
902 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
906 * crypto_shash_final() - calculate message digest
907 * @desc: operational state handle that is already filled with data
908 * @out: output buffer filled with the message digest
910 * Finalize the message digest operation and create the message digest
911 * based on all data added to the cipher handle. The message digest is placed
912 * into the output buffer. The caller must ensure that the output buffer is
913 * large enough by using crypto_shash_digestsize.
915 * Return: 0 if the message digest creation was successful; < 0 if an error
918 int crypto_shash_final(struct shash_desc *desc, u8 *out);
921 * crypto_shash_finup() - calculate message digest of buffer
922 * @desc: see crypto_shash_final()
923 * @data: see crypto_shash_update()
924 * @len: see crypto_shash_update()
925 * @out: see crypto_shash_final()
927 * This function is a "short-hand" for the function calls of
928 * crypto_shash_update and crypto_shash_final. The parameters have the same
929 * meaning as discussed for those separate functions.
931 * Return: 0 if the message digest creation was successful; < 0 if an error
934 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
935 unsigned int len, u8 *out);
937 static inline void shash_desc_zero(struct shash_desc *desc)
939 memzero_explicit(desc,
940 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
943 #endif /* _CRYPTO_HASH_H */