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