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: **[mandatory]** 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. Driver code
78 * implementation must not use req->result.
79 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
80 * function actually pushes blocks of data from upper layers into the
81 * driver, which then passes those to the hardware as seen fit. This
82 * function must not finalize the HASH transformation by calculating the
83 * final message digest as this only adds more data into the
84 * transformation. This function shall not modify the transformation
85 * context, as this function may be called in parallel with the same
86 * transformation object. Data processing can happen synchronously
87 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use
89 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
90 * transformation and retrieves the resulting hash from the driver and
91 * pushes it back to upper layers. No data processing happens at this
92 * point unless hardware requires it to finish the transformation
93 * (then the data buffered by the device driver is processed).
94 * @finup: **[optional]** Combination of @update and @final. This function is effectively a
95 * combination of @update and @final calls issued in sequence. As some
96 * hardware cannot do @update and @final separately, this callback was
97 * added to allow such hardware to be used at least by IPsec. Data
98 * processing can happen synchronously [SHASH] or asynchronously [AHASH]
100 * @digest: Combination of @init and @update and @final. This function
101 * effectively behaves as the entire chain of operations, @init,
102 * @update and @final issued in sequence. Just like @finup, this was
103 * added for hardware which cannot do even the @finup, but can only do
104 * the whole transformation in one run. Data processing can happen
105 * synchronously [SHASH] or asynchronously [AHASH] at this point.
106 * @setkey: Set optional key used by the hashing algorithm. Intended to push
107 * optional key used by the hashing algorithm from upper layers into
108 * the driver. This function can store the key in the transformation
109 * context or can outright program it into the hardware. In the former
110 * case, one must be careful to program the key into the hardware at
111 * appropriate time and one must be careful that .setkey() can be
112 * called multiple times during the existence of the transformation
113 * object. Not all hashing algorithms do implement this function as it
114 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
115 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
116 * this function. This function must be called before any other of the
117 * @init, @update, @final, @finup, @digest is called. No data
118 * processing happens at this point.
119 * @export: Export partial state of the transformation. This function dumps the
120 * entire state of the ongoing transformation into a provided block of
121 * data so it can be @import 'ed back later on. This is useful in case
122 * you want to save partial result of the transformation after
123 * processing certain amount of data and reload this partial result
124 * multiple times later on for multiple re-use. No data processing
125 * happens at this point. Driver must not use req->result.
126 * @import: Import partial state of the transformation. This function loads the
127 * entire state of the ongoing transformation from a provided block of
128 * data so the transformation can continue from this point onward. No
129 * data processing happens at this point. Driver must not use
131 * @halg: see struct hash_alg_common
134 int (*init)(struct ahash_request *req);
135 int (*update)(struct ahash_request *req);
136 int (*final)(struct ahash_request *req);
137 int (*finup)(struct ahash_request *req);
138 int (*digest)(struct ahash_request *req);
139 int (*export)(struct ahash_request *req, void *out);
140 int (*import)(struct ahash_request *req, const void *in);
141 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
142 unsigned int keylen);
144 struct hash_alg_common halg;
148 struct crypto_shash *tfm;
149 void *__ctx[] CRYPTO_MINALIGN_ATTR;
152 #define HASH_MAX_DIGESTSIZE 64
155 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc'
156 * containing a 'struct sha3_state'.
158 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360)
160 #define HASH_MAX_STATESIZE 512
162 #define SHASH_DESC_ON_STACK(shash, ctx) \
163 char __##shash##_desc[sizeof(struct shash_desc) + \
164 HASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \
165 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
168 * struct shash_alg - synchronous message digest definition
169 * @init: see struct ahash_alg
170 * @update: see struct ahash_alg
171 * @final: see struct ahash_alg
172 * @finup: see struct ahash_alg
173 * @digest: see struct ahash_alg
174 * @export: see struct ahash_alg
175 * @import: see struct ahash_alg
176 * @setkey: see struct ahash_alg
177 * @digestsize: see struct ahash_alg
178 * @statesize: see struct ahash_alg
179 * @descsize: Size of the operational state for the message digest. This state
180 * size is the memory size that needs to be allocated for
182 * @base: internally used
185 int (*init)(struct shash_desc *desc);
186 int (*update)(struct shash_desc *desc, const u8 *data,
188 int (*final)(struct shash_desc *desc, u8 *out);
189 int (*finup)(struct shash_desc *desc, const u8 *data,
190 unsigned int len, u8 *out);
191 int (*digest)(struct shash_desc *desc, const u8 *data,
192 unsigned int len, u8 *out);
193 int (*export)(struct shash_desc *desc, void *out);
194 int (*import)(struct shash_desc *desc, const void *in);
195 int (*setkey)(struct crypto_shash *tfm, const u8 *key,
196 unsigned int keylen);
198 unsigned int descsize;
200 /* These fields must match hash_alg_common. */
201 unsigned int digestsize
202 __attribute__ ((aligned(__alignof__(struct hash_alg_common))));
203 unsigned int statesize;
205 struct crypto_alg base;
208 struct crypto_ahash {
209 int (*init)(struct ahash_request *req);
210 int (*update)(struct ahash_request *req);
211 int (*final)(struct ahash_request *req);
212 int (*finup)(struct ahash_request *req);
213 int (*digest)(struct ahash_request *req);
214 int (*export)(struct ahash_request *req, void *out);
215 int (*import)(struct ahash_request *req, const void *in);
216 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
217 unsigned int keylen);
219 unsigned int reqsize;
220 struct crypto_tfm base;
223 struct crypto_shash {
224 unsigned int descsize;
225 struct crypto_tfm base;
229 * DOC: Asynchronous Message Digest API
231 * The asynchronous message digest API is used with the ciphers of type
232 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
234 * The asynchronous cipher operation discussion provided for the
235 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well.
238 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
240 return container_of(tfm, struct crypto_ahash, base);
244 * crypto_alloc_ahash() - allocate ahash cipher handle
245 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
247 * @type: specifies the type of the cipher
248 * @mask: specifies the mask for the cipher
250 * Allocate a cipher handle for an ahash. The returned struct
251 * crypto_ahash is the cipher handle that is required for any subsequent
252 * API invocation for that ahash.
254 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
255 * of an error, PTR_ERR() returns the error code.
257 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
260 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
266 * crypto_free_ahash() - zeroize and free the ahash handle
267 * @tfm: cipher handle to be freed
269 static inline void crypto_free_ahash(struct crypto_ahash *tfm)
271 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
275 * crypto_has_ahash() - Search for the availability of an ahash.
276 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
278 * @type: specifies the type of the ahash
279 * @mask: specifies the mask for the ahash
281 * Return: true when the ahash is known to the kernel crypto API; false
284 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
286 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
288 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
291 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
293 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
296 static inline unsigned int crypto_ahash_alignmask(
297 struct crypto_ahash *tfm)
299 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
303 * crypto_ahash_blocksize() - obtain block size for cipher
304 * @tfm: cipher handle
306 * The block size for the message digest cipher referenced with the cipher
307 * handle is returned.
309 * Return: block size of cipher
311 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
313 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
316 static inline struct hash_alg_common *__crypto_hash_alg_common(
317 struct crypto_alg *alg)
319 return container_of(alg, struct hash_alg_common, base);
322 static inline struct hash_alg_common *crypto_hash_alg_common(
323 struct crypto_ahash *tfm)
325 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
329 * crypto_ahash_digestsize() - obtain message digest size
330 * @tfm: cipher handle
332 * The size for the message digest created by the message digest cipher
333 * referenced with the cipher handle is returned.
336 * Return: message digest size of cipher
338 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
340 return crypto_hash_alg_common(tfm)->digestsize;
344 * crypto_ahash_statesize() - obtain size of the ahash state
345 * @tfm: cipher handle
347 * Return the size of the ahash state. With the crypto_ahash_export()
348 * function, the caller can export the state into a buffer whose size is
349 * defined with this function.
351 * Return: size of the ahash state
353 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
355 return crypto_hash_alg_common(tfm)->statesize;
358 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
360 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
363 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
365 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
368 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
370 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
374 * crypto_ahash_reqtfm() - obtain cipher handle from request
375 * @req: asynchronous request handle that contains the reference to the ahash
378 * Return the ahash cipher handle that is registered with the asynchronous
379 * request handle ahash_request.
381 * Return: ahash cipher handle
383 static inline struct crypto_ahash *crypto_ahash_reqtfm(
384 struct ahash_request *req)
386 return __crypto_ahash_cast(req->base.tfm);
390 * crypto_ahash_reqsize() - obtain size of the request data structure
391 * @tfm: cipher handle
393 * Return: size of the request data
395 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
400 static inline void *ahash_request_ctx(struct ahash_request *req)
406 * crypto_ahash_setkey - set key for cipher handle
407 * @tfm: cipher handle
408 * @key: buffer holding the key
409 * @keylen: length of the key in bytes
411 * The caller provided key is set for the ahash cipher. The cipher
412 * handle must point to a keyed hash in order for this function to succeed.
414 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
416 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
417 unsigned int keylen);
420 * crypto_ahash_finup() - update and finalize message digest
421 * @req: reference to the ahash_request handle that holds all information
422 * needed to perform the cipher operation
424 * This function is a "short-hand" for the function calls of
425 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
426 * meaning as discussed for those separate functions.
428 * Return: see crypto_ahash_final()
430 int crypto_ahash_finup(struct ahash_request *req);
433 * crypto_ahash_final() - calculate message digest
434 * @req: reference to the ahash_request handle that holds all information
435 * needed to perform the cipher operation
437 * Finalize the message digest operation and create the message digest
438 * based on all data added to the cipher handle. The message digest is placed
439 * into the output buffer registered with the ahash_request handle.
442 * 0 if the message digest was successfully calculated;
443 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later;
444 * -EBUSY if queue is full and request should be resubmitted later;
445 * other < 0 if an error occurred
447 int crypto_ahash_final(struct ahash_request *req);
450 * crypto_ahash_digest() - calculate message digest for a buffer
451 * @req: reference to the ahash_request handle that holds all information
452 * needed to perform the cipher operation
454 * This function is a "short-hand" for the function calls of crypto_ahash_init,
455 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
456 * meaning as discussed for those separate three functions.
458 * Return: see crypto_ahash_final()
460 int crypto_ahash_digest(struct ahash_request *req);
463 * crypto_ahash_export() - extract current message digest state
464 * @req: reference to the ahash_request handle whose state is exported
465 * @out: output buffer of sufficient size that can hold the hash state
467 * This function exports the hash state of the ahash_request handle into the
468 * caller-allocated output buffer out which must have sufficient size (e.g. by
469 * calling crypto_ahash_statesize()).
471 * Return: 0 if the export was successful; < 0 if an error occurred
473 static inline int crypto_ahash_export(struct ahash_request *req, void *out)
475 return crypto_ahash_reqtfm(req)->export(req, out);
479 * crypto_ahash_import() - import message digest state
480 * @req: reference to ahash_request handle the state is imported into
481 * @in: buffer holding the state
483 * This function imports the hash state into the ahash_request handle from the
484 * input buffer. That buffer should have been generated with the
485 * crypto_ahash_export function.
487 * Return: 0 if the import was successful; < 0 if an error occurred
489 static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
491 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
493 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
496 return tfm->import(req, in);
500 * crypto_ahash_init() - (re)initialize message digest handle
501 * @req: ahash_request handle that already is initialized with all necessary
502 * data using the ahash_request_* API functions
504 * The call (re-)initializes the message digest referenced by the ahash_request
505 * handle. Any potentially existing state created by previous operations is
508 * Return: see crypto_ahash_final()
510 static inline int crypto_ahash_init(struct ahash_request *req)
512 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
514 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
517 return tfm->init(req);
521 * crypto_ahash_update() - add data to message digest for processing
522 * @req: ahash_request handle that was previously initialized with the
523 * crypto_ahash_init call.
525 * Updates the message digest state of the &ahash_request handle. The input data
526 * is pointed to by the scatter/gather list registered in the &ahash_request
529 * Return: see crypto_ahash_final()
531 static inline int crypto_ahash_update(struct ahash_request *req)
533 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
534 struct crypto_alg *alg = tfm->base.__crt_alg;
535 unsigned int nbytes = req->nbytes;
538 crypto_stats_get(alg);
539 ret = crypto_ahash_reqtfm(req)->update(req);
540 crypto_stats_ahash_update(nbytes, ret, alg);
545 * DOC: Asynchronous Hash Request Handle
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.
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
560 * Allow the caller to replace the existing ahash handle in the request
561 * data structure with a different one.
563 static inline void ahash_request_set_tfm(struct ahash_request *req,
564 struct crypto_ahash *tfm)
566 req->base.tfm = crypto_ahash_tfm(tfm);
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.
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.
579 * Return: allocated request handle in case of success, or NULL if out of memory
581 static inline struct ahash_request *ahash_request_alloc(
582 struct crypto_ahash *tfm, gfp_t gfp)
584 struct ahash_request *req;
586 req = kmalloc(sizeof(struct ahash_request) +
587 crypto_ahash_reqsize(tfm), gfp);
590 ahash_request_set_tfm(req, tfm);
596 * ahash_request_free() - zeroize and free the request data structure
597 * @req: request data structure cipher handle to be freed
599 static inline void ahash_request_free(struct ahash_request *req)
604 static inline void ahash_request_zero(struct ahash_request *req)
606 memzero_explicit(req, sizeof(*req) +
607 crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
610 static inline struct ahash_request *ahash_request_cast(
611 struct crypto_async_request *req)
613 return container_of(req, struct ahash_request, base);
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.
633 * This function allows setting the callback function that is triggered once
634 * the cipher operation completes.
636 * The callback function is registered with the &ahash_request handle and
637 * must comply with the following template::
639 * void callback_function(struct crypto_async_request *req, int error)
641 static inline void ahash_request_set_callback(struct ahash_request *req,
643 crypto_completion_t compl,
646 req->base.complete = compl;
647 req->base.data = data;
648 req->base.flags = flags;
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
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
664 static inline void ahash_request_set_crypt(struct ahash_request *req,
665 struct scatterlist *src, u8 *result,
669 req->nbytes = nbytes;
670 req->result = result;
674 * DOC: Synchronous Message Digest API
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)
679 * The message digest API is able to maintain state information for the
682 * The synchronous message digest API can store user-related context in in its
683 * shash_desc request data structure.
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
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.
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.
700 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
703 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
709 * crypto_free_shash() - zeroize and free the message digest handle
710 * @tfm: cipher handle to be freed
712 static inline void crypto_free_shash(struct crypto_shash *tfm)
714 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
717 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
719 return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
722 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
724 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
727 static inline unsigned int crypto_shash_alignmask(
728 struct crypto_shash *tfm)
730 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
734 * crypto_shash_blocksize() - obtain block size for cipher
735 * @tfm: cipher handle
737 * The block size for the message digest cipher referenced with the cipher
738 * handle is returned.
740 * Return: block size of cipher
742 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
744 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
747 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
749 return container_of(alg, struct shash_alg, base);
752 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
754 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
758 * crypto_shash_digestsize() - obtain message digest size
759 * @tfm: cipher handle
761 * The size for the message digest created by the message digest cipher
762 * referenced with the cipher handle is returned.
764 * Return: digest size of cipher
766 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
768 return crypto_shash_alg(tfm)->digestsize;
771 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
773 return crypto_shash_alg(tfm)->statesize;
776 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
778 return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
781 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
783 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
786 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
788 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
792 * crypto_shash_descsize() - obtain the operational state size
793 * @tfm: cipher handle
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.
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)
804 * Return: size of the operational state
806 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
808 return tfm->descsize;
811 static inline void *shash_desc_ctx(struct shash_desc *desc)
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
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.
826 * Context: Any context.
827 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
829 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
830 unsigned int keylen);
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()
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.
843 * Context: Any context.
844 * Return: 0 if the message digest creation was successful; < 0 if an error
847 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
848 unsigned int len, u8 *out);
851 * crypto_shash_export() - extract operational state for message digest
852 * @desc: reference to the operational state handle whose state is exported
853 * @out: output buffer of sufficient size that can hold the hash state
855 * This function exports the hash state of the operational state handle into the
856 * caller-allocated output buffer out which must have sufficient size (e.g. by
857 * calling crypto_shash_descsize).
859 * Context: Any context.
860 * Return: 0 if the export creation was successful; < 0 if an error occurred
862 static inline int crypto_shash_export(struct shash_desc *desc, void *out)
864 return crypto_shash_alg(desc->tfm)->export(desc, out);
868 * crypto_shash_import() - import operational state
869 * @desc: reference to the operational state handle the state imported into
870 * @in: buffer holding the state
872 * This function imports the hash state into the operational state handle from
873 * the input buffer. That buffer should have been generated with the
874 * crypto_ahash_export function.
876 * Context: Any context.
877 * Return: 0 if the import was successful; < 0 if an error occurred
879 static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
881 struct crypto_shash *tfm = desc->tfm;
883 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
886 return crypto_shash_alg(tfm)->import(desc, in);
890 * crypto_shash_init() - (re)initialize message digest
891 * @desc: operational state handle that is already filled
893 * The call (re-)initializes the message digest referenced by the
894 * operational state handle. Any potentially existing state created by
895 * previous operations is discarded.
897 * Context: Any context.
898 * Return: 0 if the message digest initialization was successful; < 0 if an
901 static inline int crypto_shash_init(struct shash_desc *desc)
903 struct crypto_shash *tfm = desc->tfm;
905 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
908 return crypto_shash_alg(tfm)->init(desc);
912 * crypto_shash_update() - add data to message digest for processing
913 * @desc: operational state handle that is already initialized
914 * @data: input data to be added to the message digest
915 * @len: length of the input data
917 * Updates the message digest state of the operational state handle.
919 * Context: Any context.
920 * Return: 0 if the message digest update was successful; < 0 if an error
923 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
927 * crypto_shash_final() - calculate message digest
928 * @desc: operational state handle that is already filled with data
929 * @out: output buffer filled with the message digest
931 * Finalize the message digest operation and create the message digest
932 * based on all data added to the cipher handle. The message digest is placed
933 * into the output buffer. The caller must ensure that the output buffer is
934 * large enough by using crypto_shash_digestsize.
936 * Context: Any context.
937 * Return: 0 if the message digest creation was successful; < 0 if an error
940 int crypto_shash_final(struct shash_desc *desc, u8 *out);
943 * crypto_shash_finup() - calculate message digest of buffer
944 * @desc: see crypto_shash_final()
945 * @data: see crypto_shash_update()
946 * @len: see crypto_shash_update()
947 * @out: see crypto_shash_final()
949 * This function is a "short-hand" for the function calls of
950 * crypto_shash_update and crypto_shash_final. The parameters have the same
951 * meaning as discussed for those separate functions.
953 * Context: Any context.
954 * Return: 0 if the message digest creation was successful; < 0 if an error
957 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
958 unsigned int len, u8 *out);
960 static inline void shash_desc_zero(struct shash_desc *desc)
962 memzero_explicit(desc,
963 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
966 #endif /* _CRYPTO_HASH_H */