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.
79 * @update: 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.
89 * @final: 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).
95 * @finup: Combination of @update and @final. This function is effectively a
96 * combination of @update and @final calls issued in sequence. As some
97 * hardware cannot do @update and @final separately, this callback was
98 * added to allow such hardware to be used at least by IPsec. Data
99 * processing can happen synchronously [SHASH] or asynchronously [AHASH]
102 * @digest: Combination of @init and @update and @final. This function
103 * effectively behaves as the entire chain of operations, @init,
104 * @update and @final issued in sequence. Just like @finup, this was
105 * added for hardware which cannot do even the @finup, but can only do
106 * the whole transformation in one run. Data processing can happen
107 * synchronously [SHASH] or asynchronously [AHASH] at this point.
108 * @setkey: Set optional key used by the hashing algorithm. Intended to push
109 * optional key used by the hashing algorithm from upper layers into
110 * the driver. This function can store the key in the transformation
111 * context or can outright program it into the hardware. In the former
112 * case, one must be careful to program the key into the hardware at
113 * appropriate time and one must be careful that .setkey() can be
114 * called multiple times during the existence of the transformation
115 * object. Not all hashing algorithms do implement this function as it
116 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
117 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
118 * this function. This function must be called before any other of the
119 * @init, @update, @final, @finup, @digest is called. No data
120 * processing happens at this point.
121 * @export: Export partial state of the transformation. This function dumps the
122 * entire state of the ongoing transformation into a provided block of
123 * data so it can be @import 'ed back later on. This is useful in case
124 * you want to save partial result of the transformation after
125 * processing certain amount of data and reload this partial result
126 * multiple times later on for multiple re-use. No data processing
127 * happens at this point.
128 * @import: Import partial state of the transformation. This function loads the
129 * entire state of the ongoing transformation from a provided block of
130 * data so the transformation can continue from this point onward. No
131 * data processing happens at this point.
132 * @halg: see struct hash_alg_common
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
);
145 struct hash_alg_common halg
;
149 struct crypto_shash
*tfm
;
152 void *__ctx
[] CRYPTO_MINALIGN_ATTR
;
155 #define SHASH_DESC_ON_STACK(shash, ctx) \
156 char __##shash##_desc[sizeof(struct shash_desc) + \
157 crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
158 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
161 * struct shash_alg - synchronous message digest definition
162 * @init: see struct ahash_alg
163 * @update: see struct ahash_alg
164 * @final: see struct ahash_alg
165 * @finup: see struct ahash_alg
166 * @digest: see struct ahash_alg
167 * @export: see struct ahash_alg
168 * @import: see struct ahash_alg
169 * @setkey: see struct ahash_alg
170 * @digestsize: see struct ahash_alg
171 * @statesize: see struct ahash_alg
172 * @descsize: Size of the operational state for the message digest. This state
173 * size is the memory size that needs to be allocated for
175 * @base: internally used
178 int (*init
)(struct shash_desc
*desc
);
179 int (*update
)(struct shash_desc
*desc
, const u8
*data
,
181 int (*final
)(struct shash_desc
*desc
, u8
*out
);
182 int (*finup
)(struct shash_desc
*desc
, const u8
*data
,
183 unsigned int len
, u8
*out
);
184 int (*digest
)(struct shash_desc
*desc
, const u8
*data
,
185 unsigned int len
, u8
*out
);
186 int (*export
)(struct shash_desc
*desc
, void *out
);
187 int (*import
)(struct shash_desc
*desc
, const void *in
);
188 int (*setkey
)(struct crypto_shash
*tfm
, const u8
*key
,
189 unsigned int keylen
);
191 unsigned int descsize
;
193 /* These fields must match hash_alg_common. */
194 unsigned int digestsize
195 __attribute__ ((aligned(__alignof__(struct hash_alg_common
))));
196 unsigned int statesize
;
198 struct crypto_alg base
;
201 struct crypto_ahash
{
202 int (*init
)(struct ahash_request
*req
);
203 int (*update
)(struct ahash_request
*req
);
204 int (*final
)(struct ahash_request
*req
);
205 int (*finup
)(struct ahash_request
*req
);
206 int (*digest
)(struct ahash_request
*req
);
207 int (*export
)(struct ahash_request
*req
, void *out
);
208 int (*import
)(struct ahash_request
*req
, const void *in
);
209 int (*setkey
)(struct crypto_ahash
*tfm
, const u8
*key
,
210 unsigned int keylen
);
212 unsigned int reqsize
;
213 struct crypto_tfm base
;
216 struct crypto_shash
{
217 unsigned int descsize
;
218 struct crypto_tfm base
;
222 * DOC: Asynchronous Message Digest API
224 * The asynchronous message digest API is used with the ciphers of type
225 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
227 * The asynchronous cipher operation discussion provided for the
228 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well.
231 static inline struct crypto_ahash
*__crypto_ahash_cast(struct crypto_tfm
*tfm
)
233 return container_of(tfm
, struct crypto_ahash
, base
);
237 * crypto_alloc_ahash() - allocate ahash cipher handle
238 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
240 * @type: specifies the type of the cipher
241 * @mask: specifies the mask for the cipher
243 * Allocate a cipher handle for an ahash. The returned struct
244 * crypto_ahash is the cipher handle that is required for any subsequent
245 * API invocation for that ahash.
247 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
248 * of an error, PTR_ERR() returns the error code.
250 struct crypto_ahash
*crypto_alloc_ahash(const char *alg_name
, u32 type
,
253 static inline struct crypto_tfm
*crypto_ahash_tfm(struct crypto_ahash
*tfm
)
259 * crypto_free_ahash() - zeroize and free the ahash handle
260 * @tfm: cipher handle to be freed
262 static inline void crypto_free_ahash(struct crypto_ahash
*tfm
)
264 crypto_destroy_tfm(tfm
, crypto_ahash_tfm(tfm
));
268 * crypto_has_ahash() - Search for the availability of an ahash.
269 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
271 * @type: specifies the type of the ahash
272 * @mask: specifies the mask for the ahash
274 * Return: true when the ahash is known to the kernel crypto API; false
277 int crypto_has_ahash(const char *alg_name
, u32 type
, u32 mask
);
279 static inline const char *crypto_ahash_alg_name(struct crypto_ahash
*tfm
)
281 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm
));
284 static inline const char *crypto_ahash_driver_name(struct crypto_ahash
*tfm
)
286 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm
));
289 static inline unsigned int crypto_ahash_alignmask(
290 struct crypto_ahash
*tfm
)
292 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm
));
296 * crypto_ahash_blocksize() - obtain block size for cipher
297 * @tfm: cipher handle
299 * The block size for the message digest cipher referenced with the cipher
300 * handle is returned.
302 * Return: block size of cipher
304 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash
*tfm
)
306 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm
));
309 static inline struct hash_alg_common
*__crypto_hash_alg_common(
310 struct crypto_alg
*alg
)
312 return container_of(alg
, struct hash_alg_common
, base
);
315 static inline struct hash_alg_common
*crypto_hash_alg_common(
316 struct crypto_ahash
*tfm
)
318 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm
)->__crt_alg
);
322 * crypto_ahash_digestsize() - obtain message digest size
323 * @tfm: cipher handle
325 * The size for the message digest created by the message digest cipher
326 * referenced with the cipher handle is returned.
329 * Return: message digest size of cipher
331 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash
*tfm
)
333 return crypto_hash_alg_common(tfm
)->digestsize
;
337 * crypto_ahash_statesize() - obtain size of the ahash state
338 * @tfm: cipher handle
340 * Return the size of the ahash state. With the crypto_ahash_export()
341 * function, the caller can export the state into a buffer whose size is
342 * defined with this function.
344 * Return: size of the ahash state
346 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash
*tfm
)
348 return crypto_hash_alg_common(tfm
)->statesize
;
351 static inline u32
crypto_ahash_get_flags(struct crypto_ahash
*tfm
)
353 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm
));
356 static inline void crypto_ahash_set_flags(struct crypto_ahash
*tfm
, u32 flags
)
358 crypto_tfm_set_flags(crypto_ahash_tfm(tfm
), flags
);
361 static inline void crypto_ahash_clear_flags(struct crypto_ahash
*tfm
, u32 flags
)
363 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm
), flags
);
367 * crypto_ahash_reqtfm() - obtain cipher handle from request
368 * @req: asynchronous request handle that contains the reference to the ahash
371 * Return the ahash cipher handle that is registered with the asynchronous
372 * request handle ahash_request.
374 * Return: ahash cipher handle
376 static inline struct crypto_ahash
*crypto_ahash_reqtfm(
377 struct ahash_request
*req
)
379 return __crypto_ahash_cast(req
->base
.tfm
);
383 * crypto_ahash_reqsize() - obtain size of the request data structure
384 * @tfm: cipher handle
386 * Return: size of the request data
388 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash
*tfm
)
393 static inline void *ahash_request_ctx(struct ahash_request
*req
)
399 * crypto_ahash_setkey - set key for cipher handle
400 * @tfm: cipher handle
401 * @key: buffer holding the key
402 * @keylen: length of the key in bytes
404 * The caller provided key is set for the ahash cipher. The cipher
405 * handle must point to a keyed hash in order for this function to succeed.
407 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
409 int crypto_ahash_setkey(struct crypto_ahash
*tfm
, const u8
*key
,
410 unsigned int keylen
);
413 * crypto_ahash_finup() - update and finalize message digest
414 * @req: reference to the ahash_request handle that holds all information
415 * needed to perform the cipher operation
417 * This function is a "short-hand" for the function calls of
418 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
419 * meaning as discussed for those separate functions.
421 * Return: see crypto_ahash_final()
423 int crypto_ahash_finup(struct ahash_request
*req
);
426 * crypto_ahash_final() - calculate message digest
427 * @req: reference to the ahash_request handle that holds all information
428 * needed to perform the cipher operation
430 * Finalize the message digest operation and create the message digest
431 * based on all data added to the cipher handle. The message digest is placed
432 * into the output buffer registered with the ahash_request handle.
435 * 0 if the message digest was successfully calculated;
436 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later;
437 * -EBUSY if queue is full and request should be resubmitted later;
438 * other < 0 if an error occurred
440 int crypto_ahash_final(struct ahash_request
*req
);
443 * crypto_ahash_digest() - calculate message digest for a buffer
444 * @req: reference to the ahash_request handle that holds all information
445 * needed to perform the cipher operation
447 * This function is a "short-hand" for the function calls of crypto_ahash_init,
448 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
449 * meaning as discussed for those separate three functions.
451 * Return: see crypto_ahash_final()
453 int crypto_ahash_digest(struct ahash_request
*req
);
456 * crypto_ahash_export() - extract current message digest state
457 * @req: reference to the ahash_request handle whose state is exported
458 * @out: output buffer of sufficient size that can hold the hash state
460 * This function exports the hash state of the ahash_request handle into the
461 * caller-allocated output buffer out which must have sufficient size (e.g. by
462 * calling crypto_ahash_statesize()).
464 * Return: 0 if the export was successful; < 0 if an error occurred
466 static inline int crypto_ahash_export(struct ahash_request
*req
, void *out
)
468 return crypto_ahash_reqtfm(req
)->export(req
, out
);
472 * crypto_ahash_import() - import message digest state
473 * @req: reference to ahash_request handle the state is imported into
474 * @in: buffer holding the state
476 * This function imports the hash state into the ahash_request handle from the
477 * input buffer. That buffer should have been generated with the
478 * crypto_ahash_export function.
480 * Return: 0 if the import was successful; < 0 if an error occurred
482 static inline int crypto_ahash_import(struct ahash_request
*req
, const void *in
)
484 struct crypto_ahash
*tfm
= crypto_ahash_reqtfm(req
);
486 if (crypto_ahash_get_flags(tfm
) & CRYPTO_TFM_NEED_KEY
)
489 return tfm
->import(req
, in
);
493 * crypto_ahash_init() - (re)initialize message digest handle
494 * @req: ahash_request handle that already is initialized with all necessary
495 * data using the ahash_request_* API functions
497 * The call (re-)initializes the message digest referenced by the ahash_request
498 * handle. Any potentially existing state created by previous operations is
501 * Return: see crypto_ahash_final()
503 static inline int crypto_ahash_init(struct ahash_request
*req
)
505 struct crypto_ahash
*tfm
= crypto_ahash_reqtfm(req
);
507 if (crypto_ahash_get_flags(tfm
) & CRYPTO_TFM_NEED_KEY
)
510 return tfm
->init(req
);
514 * crypto_ahash_update() - add data to message digest for processing
515 * @req: ahash_request handle that was previously initialized with the
516 * crypto_ahash_init call.
518 * Updates the message digest state of the &ahash_request handle. The input data
519 * is pointed to by the scatter/gather list registered in the &ahash_request
522 * Return: see crypto_ahash_final()
524 static inline int crypto_ahash_update(struct ahash_request
*req
)
526 return crypto_ahash_reqtfm(req
)->update(req
);
530 * DOC: Asynchronous Hash Request Handle
532 * The &ahash_request data structure contains all pointers to data
533 * required for the asynchronous cipher operation. This includes the cipher
534 * handle (which can be used by multiple &ahash_request instances), pointer
535 * to plaintext and the message digest output buffer, asynchronous callback
536 * function, etc. It acts as a handle to the ahash_request_* API calls in a
537 * similar way as ahash handle to the crypto_ahash_* API calls.
541 * ahash_request_set_tfm() - update cipher handle reference in request
542 * @req: request handle to be modified
543 * @tfm: cipher handle that shall be added to the request handle
545 * Allow the caller to replace the existing ahash handle in the request
546 * data structure with a different one.
548 static inline void ahash_request_set_tfm(struct ahash_request
*req
,
549 struct crypto_ahash
*tfm
)
551 req
->base
.tfm
= crypto_ahash_tfm(tfm
);
555 * ahash_request_alloc() - allocate request data structure
556 * @tfm: cipher handle to be registered with the request
557 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
559 * Allocate the request data structure that must be used with the ahash
560 * message digest API calls. During
561 * the allocation, the provided ahash handle
562 * is registered in the request data structure.
564 * Return: allocated request handle in case of success, or NULL if out of memory
566 static inline struct ahash_request
*ahash_request_alloc(
567 struct crypto_ahash
*tfm
, gfp_t gfp
)
569 struct ahash_request
*req
;
571 req
= kmalloc(sizeof(struct ahash_request
) +
572 crypto_ahash_reqsize(tfm
), gfp
);
575 ahash_request_set_tfm(req
, tfm
);
581 * ahash_request_free() - zeroize and free the request data structure
582 * @req: request data structure cipher handle to be freed
584 static inline void ahash_request_free(struct ahash_request
*req
)
589 static inline void ahash_request_zero(struct ahash_request
*req
)
591 memzero_explicit(req
, sizeof(*req
) +
592 crypto_ahash_reqsize(crypto_ahash_reqtfm(req
)));
595 static inline struct ahash_request
*ahash_request_cast(
596 struct crypto_async_request
*req
)
598 return container_of(req
, struct ahash_request
, base
);
602 * ahash_request_set_callback() - set asynchronous callback function
603 * @req: request handle
604 * @flags: specify zero or an ORing of the flags
605 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
606 * increase the wait queue beyond the initial maximum size;
607 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
608 * @compl: callback function pointer to be registered with the request handle
609 * @data: The data pointer refers to memory that is not used by the kernel
610 * crypto API, but provided to the callback function for it to use. Here,
611 * the caller can provide a reference to memory the callback function can
612 * operate on. As the callback function is invoked asynchronously to the
613 * related functionality, it may need to access data structures of the
614 * related functionality which can be referenced using this pointer. The
615 * callback function can access the memory via the "data" field in the
616 * &crypto_async_request data structure provided to the callback function.
618 * This function allows setting the callback function that is triggered once
619 * the cipher operation completes.
621 * The callback function is registered with the &ahash_request handle and
622 * must comply with the following template::
624 * void callback_function(struct crypto_async_request *req, int error)
626 static inline void ahash_request_set_callback(struct ahash_request
*req
,
628 crypto_completion_t
compl,
631 req
->base
.complete
= compl;
632 req
->base
.data
= data
;
633 req
->base
.flags
= flags
;
637 * ahash_request_set_crypt() - set data buffers
638 * @req: ahash_request handle to be updated
639 * @src: source scatter/gather list
640 * @result: buffer that is filled with the message digest -- the caller must
641 * ensure that the buffer has sufficient space by, for example, calling
642 * crypto_ahash_digestsize()
643 * @nbytes: number of bytes to process from the source scatter/gather list
645 * By using this call, the caller references the source scatter/gather list.
646 * The source scatter/gather list points to the data the message digest is to
649 static inline void ahash_request_set_crypt(struct ahash_request
*req
,
650 struct scatterlist
*src
, u8
*result
,
654 req
->nbytes
= nbytes
;
655 req
->result
= result
;
659 * DOC: Synchronous Message Digest API
661 * The synchronous message digest API is used with the ciphers of type
662 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
664 * The message digest API is able to maintain state information for the
667 * The synchronous message digest API can store user-related context in in its
668 * shash_desc request data structure.
672 * crypto_alloc_shash() - allocate message digest handle
673 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
674 * message digest cipher
675 * @type: specifies the type of the cipher
676 * @mask: specifies the mask for the cipher
678 * Allocate a cipher handle for a message digest. The returned &struct
679 * crypto_shash is the cipher handle that is required for any subsequent
680 * API invocation for that message digest.
682 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
683 * of an error, PTR_ERR() returns the error code.
685 struct crypto_shash
*crypto_alloc_shash(const char *alg_name
, u32 type
,
688 static inline struct crypto_tfm
*crypto_shash_tfm(struct crypto_shash
*tfm
)
694 * crypto_free_shash() - zeroize and free the message digest handle
695 * @tfm: cipher handle to be freed
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 */