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 HASH_MAX_DIGESTSIZE 64
155#define HASH_MAX_DESCSIZE 360
156#define HASH_MAX_STATESIZE 512
157
158#define SHASH_DESC_ON_STACK(shash, ctx) \
159 char __##shash##_desc[sizeof(struct shash_desc) + \
160 HASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \
161 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
162
163/**
164 * struct shash_alg - synchronous message digest definition
165 * @init: see struct ahash_alg
166 * @update: see struct ahash_alg
167 * @final: see struct ahash_alg
168 * @finup: see struct ahash_alg
169 * @digest: see struct ahash_alg
170 * @export: see struct ahash_alg
171 * @import: see struct ahash_alg
172 * @setkey: see struct ahash_alg
173 * @digestsize: see struct ahash_alg
174 * @statesize: see struct ahash_alg
175 * @descsize: Size of the operational state for the message digest. This state
176 * size is the memory size that needs to be allocated for
177 * shash_desc.__ctx
178 * @base: internally used
179 */
180struct shash_alg {
181 int (*init)(struct shash_desc *desc);
182 int (*update)(struct shash_desc *desc, const u8 *data,
183 unsigned int len);
184 int (*final)(struct shash_desc *desc, u8 *out);
185 int (*finup)(struct shash_desc *desc, const u8 *data,
186 unsigned int len, u8 *out);
187 int (*digest)(struct shash_desc *desc, const u8 *data,
188 unsigned int len, u8 *out);
189 int (*export)(struct shash_desc *desc, void *out);
190 int (*import)(struct shash_desc *desc, const void *in);
191 int (*setkey)(struct crypto_shash *tfm, const u8 *key,
192 unsigned int keylen);
193
194 unsigned int descsize;
195
196 /* These fields must match hash_alg_common. */
197 unsigned int digestsize
198 __attribute__ ((aligned(__alignof__(struct hash_alg_common))));
199 unsigned int statesize;
200
201 struct crypto_alg base;
202};
203
204struct crypto_ahash {
205 int (*init)(struct ahash_request *req);
206 int (*update)(struct ahash_request *req);
207 int (*final)(struct ahash_request *req);
208 int (*finup)(struct ahash_request *req);
209 int (*digest)(struct ahash_request *req);
210 int (*export)(struct ahash_request *req, void *out);
211 int (*import)(struct ahash_request *req, const void *in);
212 int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
213 unsigned int keylen);
214
215 unsigned int reqsize;
216 struct crypto_tfm base;
217};
218
219struct crypto_shash {
220 unsigned int descsize;
221 struct crypto_tfm base;
222};
223
224/**
225 * DOC: Asynchronous Message Digest API
226 *
227 * The asynchronous message digest API is used with the ciphers of type
228 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
229 *
230 * The asynchronous cipher operation discussion provided for the
231 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well.
232 */
233
234static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
235{
236 return container_of(tfm, struct crypto_ahash, base);
237}
238
239/**
240 * crypto_alloc_ahash() - allocate ahash cipher handle
241 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
242 * ahash cipher
243 * @type: specifies the type of the cipher
244 * @mask: specifies the mask for the cipher
245 *
246 * Allocate a cipher handle for an ahash. The returned struct
247 * crypto_ahash is the cipher handle that is required for any subsequent
248 * API invocation for that ahash.
249 *
250 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
251 * of an error, PTR_ERR() returns the error code.
252 */
253struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
254 u32 mask);
255
256static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
257{
258 return &tfm->base;
259}
260
261/**
262 * crypto_free_ahash() - zeroize and free the ahash handle
263 * @tfm: cipher handle to be freed
264 */
265static inline void crypto_free_ahash(struct crypto_ahash *tfm)
266{
267 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
268}
269
270/**
271 * crypto_has_ahash() - Search for the availability of an ahash.
272 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
273 * ahash
274 * @type: specifies the type of the ahash
275 * @mask: specifies the mask for the ahash
276 *
277 * Return: true when the ahash is known to the kernel crypto API; false
278 * otherwise
279 */
280int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
281
282static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
283{
284 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
285}
286
287static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
288{
289 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
290}
291
292static inline unsigned int crypto_ahash_alignmask(
293 struct crypto_ahash *tfm)
294{
295 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
296}
297
298/**
299 * crypto_ahash_blocksize() - obtain block size for cipher
300 * @tfm: cipher handle
301 *
302 * The block size for the message digest cipher referenced with the cipher
303 * handle is returned.
304 *
305 * Return: block size of cipher
306 */
307static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
308{
309 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
310}
311
312static inline struct hash_alg_common *__crypto_hash_alg_common(
313 struct crypto_alg *alg)
314{
315 return container_of(alg, struct hash_alg_common, base);
316}
317
318static inline struct hash_alg_common *crypto_hash_alg_common(
319 struct crypto_ahash *tfm)
320{
321 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
322}
323
324/**
325 * crypto_ahash_digestsize() - obtain message digest size
326 * @tfm: cipher handle
327 *
328 * The size for the message digest created by the message digest cipher
329 * referenced with the cipher handle is returned.
330 *
331 *
332 * Return: message digest size of cipher
333 */
334static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
335{
336 return crypto_hash_alg_common(tfm)->digestsize;
337}
338
339/**
340 * crypto_ahash_statesize() - obtain size of the ahash state
341 * @tfm: cipher handle
342 *
343 * Return the size of the ahash state. With the crypto_ahash_export()
344 * function, the caller can export the state into a buffer whose size is
345 * defined with this function.
346 *
347 * Return: size of the ahash state
348 */
349static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
350{
351 return crypto_hash_alg_common(tfm)->statesize;
352}
353
354static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
355{
356 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
357}
358
359static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
360{
361 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
362}
363
364static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
365{
366 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
367}
368
369/**
370 * crypto_ahash_reqtfm() - obtain cipher handle from request
371 * @req: asynchronous request handle that contains the reference to the ahash
372 * cipher handle
373 *
374 * Return the ahash cipher handle that is registered with the asynchronous
375 * request handle ahash_request.
376 *
377 * Return: ahash cipher handle
378 */
379static inline struct crypto_ahash *crypto_ahash_reqtfm(
380 struct ahash_request *req)
381{
382 return __crypto_ahash_cast(req->base.tfm);
383}
384
385/**
386 * crypto_ahash_reqsize() - obtain size of the request data structure
387 * @tfm: cipher handle
388 *
389 * Return: size of the request data
390 */
391static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
392{
393 return tfm->reqsize;
394}
395
396static inline void *ahash_request_ctx(struct ahash_request *req)
397{
398 return req->__ctx;
399}
400
401/**
402 * crypto_ahash_setkey - set key for cipher handle
403 * @tfm: cipher handle
404 * @key: buffer holding the key
405 * @keylen: length of the key in bytes
406 *
407 * The caller provided key is set for the ahash cipher. The cipher
408 * handle must point to a keyed hash in order for this function to succeed.
409 *
410 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
411 */
412int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
413 unsigned int keylen);
414
415/**
416 * crypto_ahash_finup() - update and finalize message digest
417 * @req: reference to the ahash_request handle that holds all information
418 * needed to perform the cipher operation
419 *
420 * This function is a "short-hand" for the function calls of
421 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
422 * meaning as discussed for those separate functions.
423 *
424 * Return: see crypto_ahash_final()
425 */
426int crypto_ahash_finup(struct ahash_request *req);
427
428/**
429 * crypto_ahash_final() - calculate message digest
430 * @req: reference to the ahash_request handle that holds all information
431 * needed to perform the cipher operation
432 *
433 * Finalize the message digest operation and create the message digest
434 * based on all data added to the cipher handle. The message digest is placed
435 * into the output buffer registered with the ahash_request handle.
436 *
437 * Return:
438 * 0 if the message digest was successfully calculated;
439 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later;
440 * -EBUSY if queue is full and request should be resubmitted later;
441 * other < 0 if an error occurred
442 */
443int crypto_ahash_final(struct ahash_request *req);
444
445/**
446 * crypto_ahash_digest() - calculate message digest for a buffer
447 * @req: reference to the ahash_request handle that holds all information
448 * needed to perform the cipher operation
449 *
450 * This function is a "short-hand" for the function calls of crypto_ahash_init,
451 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
452 * meaning as discussed for those separate three functions.
453 *
454 * Return: see crypto_ahash_final()
455 */
456int crypto_ahash_digest(struct ahash_request *req);
457
458/**
459 * crypto_ahash_export() - extract current message digest state
460 * @req: reference to the ahash_request handle whose state is exported
461 * @out: output buffer of sufficient size that can hold the hash state
462 *
463 * This function exports the hash state of the ahash_request handle into the
464 * caller-allocated output buffer out which must have sufficient size (e.g. by
465 * calling crypto_ahash_statesize()).
466 *
467 * Return: 0 if the export was successful; < 0 if an error occurred
468 */
469static inline int crypto_ahash_export(struct ahash_request *req, void *out)
470{
471 return crypto_ahash_reqtfm(req)->export(req, out);
472}
473
474/**
475 * crypto_ahash_import() - import message digest state
476 * @req: reference to ahash_request handle the state is imported into
477 * @in: buffer holding the state
478 *
479 * This function imports the hash state into the ahash_request handle from the
480 * input buffer. That buffer should have been generated with the
481 * crypto_ahash_export function.
482 *
483 * Return: 0 if the import was successful; < 0 if an error occurred
484 */
485static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
486{
487 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
488
489 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
490 return -ENOKEY;
491
492 return tfm->import(req, in);
493}
494
495/**
496 * crypto_ahash_init() - (re)initialize message digest handle
497 * @req: ahash_request handle that already is initialized with all necessary
498 * data using the ahash_request_* API functions
499 *
500 * The call (re-)initializes the message digest referenced by the ahash_request
501 * handle. Any potentially existing state created by previous operations is
502 * discarded.
503 *
504 * Return: see crypto_ahash_final()
505 */
506static inline int crypto_ahash_init(struct ahash_request *req)
507{
508 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
509
510 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
511 return -ENOKEY;
512
513 return tfm->init(req);
514}
515
516/**
517 * crypto_ahash_update() - add data to message digest for processing
518 * @req: ahash_request handle that was previously initialized with the
519 * crypto_ahash_init call.
520 *
521 * Updates the message digest state of the &ahash_request handle. The input data
522 * is pointed to by the scatter/gather list registered in the &ahash_request
523 * handle
524 *
525 * Return: see crypto_ahash_final()
526 */
527static inline int crypto_ahash_update(struct ahash_request *req)
528{
529 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
530 struct crypto_alg *alg = tfm->base.__crt_alg;
531 unsigned int nbytes = req->nbytes;
532 int ret;
533
534 crypto_stats_get(alg);
535 ret = crypto_ahash_reqtfm(req)->update(req);
536 crypto_stats_ahash_update(nbytes, ret, alg);
537 return ret;
538}
539
540/**
541 * DOC: Asynchronous Hash Request Handle
542 *
543 * The &ahash_request data structure contains all pointers to data
544 * required for the asynchronous cipher operation. This includes the cipher
545 * handle (which can be used by multiple &ahash_request instances), pointer
546 * to plaintext and the message digest output buffer, asynchronous callback
547 * function, etc. It acts as a handle to the ahash_request_* API calls in a
548 * similar way as ahash handle to the crypto_ahash_* API calls.
549 */
550
551/**
552 * ahash_request_set_tfm() - update cipher handle reference in request
553 * @req: request handle to be modified
554 * @tfm: cipher handle that shall be added to the request handle
555 *
556 * Allow the caller to replace the existing ahash handle in the request
557 * data structure with a different one.
558 */
559static inline void ahash_request_set_tfm(struct ahash_request *req,
560 struct crypto_ahash *tfm)
561{
562 req->base.tfm = crypto_ahash_tfm(tfm);
563}
564
565/**
566 * ahash_request_alloc() - allocate request data structure
567 * @tfm: cipher handle to be registered with the request
568 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
569 *
570 * Allocate the request data structure that must be used with the ahash
571 * message digest API calls. During
572 * the allocation, the provided ahash handle
573 * is registered in the request data structure.
574 *
575 * Return: allocated request handle in case of success, or NULL if out of memory
576 */
577static inline struct ahash_request *ahash_request_alloc(
578 struct crypto_ahash *tfm, gfp_t gfp)
579{
580 struct ahash_request *req;
581
582 req = kmalloc(sizeof(struct ahash_request) +
583 crypto_ahash_reqsize(tfm), gfp);
584
585 if (likely(req))
586 ahash_request_set_tfm(req, tfm);
587
588 return req;
589}
590
591/**
592 * ahash_request_free() - zeroize and free the request data structure
593 * @req: request data structure cipher handle to be freed
594 */
595static inline void ahash_request_free(struct ahash_request *req)
596{
597 kzfree(req);
598}
599
600static inline void ahash_request_zero(struct ahash_request *req)
601{
602 memzero_explicit(req, sizeof(*req) +
603 crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
604}
605
606static inline struct ahash_request *ahash_request_cast(
607 struct crypto_async_request *req)
608{
609 return container_of(req, struct ahash_request, base);
610}
611
612/**
613 * ahash_request_set_callback() - set asynchronous callback function
614 * @req: request handle
615 * @flags: specify zero or an ORing of the flags
616 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
617 * increase the wait queue beyond the initial maximum size;
618 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
619 * @compl: callback function pointer to be registered with the request handle
620 * @data: The data pointer refers to memory that is not used by the kernel
621 * crypto API, but provided to the callback function for it to use. Here,
622 * the caller can provide a reference to memory the callback function can
623 * operate on. As the callback function is invoked asynchronously to the
624 * related functionality, it may need to access data structures of the
625 * related functionality which can be referenced using this pointer. The
626 * callback function can access the memory via the "data" field in the
627 * &crypto_async_request data structure provided to the callback function.
628 *
629 * This function allows setting the callback function that is triggered once
630 * the cipher operation completes.
631 *
632 * The callback function is registered with the &ahash_request handle and
633 * must comply with the following template::
634 *
635 * void callback_function(struct crypto_async_request *req, int error)
636 */
637static inline void ahash_request_set_callback(struct ahash_request *req,
638 u32 flags,
639 crypto_completion_t compl,
640 void *data)
641{
642 req->base.complete = compl;
643 req->base.data = data;
644 req->base.flags = flags;
645}
646
647/**
648 * ahash_request_set_crypt() - set data buffers
649 * @req: ahash_request handle to be updated
650 * @src: source scatter/gather list
651 * @result: buffer that is filled with the message digest -- the caller must
652 * ensure that the buffer has sufficient space by, for example, calling
653 * crypto_ahash_digestsize()
654 * @nbytes: number of bytes to process from the source scatter/gather list
655 *
656 * By using this call, the caller references the source scatter/gather list.
657 * The source scatter/gather list points to the data the message digest is to
658 * be calculated for.
659 */
660static inline void ahash_request_set_crypt(struct ahash_request *req,
661 struct scatterlist *src, u8 *result,
662 unsigned int nbytes)
663{
664 req->src = src;
665 req->nbytes = nbytes;
666 req->result = result;
667}
668
669/**
670 * DOC: Synchronous Message Digest API
671 *
672 * The synchronous message digest API is used with the ciphers of type
673 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
674 *
675 * The message digest API is able to maintain state information for the
676 * caller.
677 *
678 * The synchronous message digest API can store user-related context in in its
679 * shash_desc request data structure.
680 */
681
682/**
683 * crypto_alloc_shash() - allocate message digest handle
684 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
685 * message digest cipher
686 * @type: specifies the type of the cipher
687 * @mask: specifies the mask for the cipher
688 *
689 * Allocate a cipher handle for a message digest. The returned &struct
690 * crypto_shash is the cipher handle that is required for any subsequent
691 * API invocation for that message digest.
692 *
693 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
694 * of an error, PTR_ERR() returns the error code.
695 */
696struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
697 u32 mask);
698
699static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
700{
701 return &tfm->base;
702}
703
704/**
705 * crypto_free_shash() - zeroize and free the message digest handle
706 * @tfm: cipher handle to be freed
707 */
708static inline void crypto_free_shash(struct crypto_shash *tfm)
709{
710 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
711}
712
713static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
714{
715 return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
716}
717
718static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
719{
720 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
721}
722
723static inline unsigned int crypto_shash_alignmask(
724 struct crypto_shash *tfm)
725{
726 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
727}
728
729/**
730 * crypto_shash_blocksize() - obtain block size for cipher
731 * @tfm: cipher handle
732 *
733 * The block size for the message digest cipher referenced with the cipher
734 * handle is returned.
735 *
736 * Return: block size of cipher
737 */
738static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
739{
740 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
741}
742
743static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
744{
745 return container_of(alg, struct shash_alg, base);
746}
747
748static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
749{
750 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
751}
752
753/**
754 * crypto_shash_digestsize() - obtain message digest size
755 * @tfm: cipher handle
756 *
757 * The size for the message digest created by the message digest cipher
758 * referenced with the cipher handle is returned.
759 *
760 * Return: digest size of cipher
761 */
762static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
763{
764 return crypto_shash_alg(tfm)->digestsize;
765}
766
767static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
768{
769 return crypto_shash_alg(tfm)->statesize;
770}
771
772static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
773{
774 return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
775}
776
777static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
778{
779 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
780}
781
782static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
783{
784 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
785}
786
787/**
788 * crypto_shash_descsize() - obtain the operational state size
789 * @tfm: cipher handle
790 *
791 * The size of the operational state the cipher needs during operation is
792 * returned for the hash referenced with the cipher handle. This size is
793 * required to calculate the memory requirements to allow the caller allocating
794 * sufficient memory for operational state.
795 *
796 * The operational state is defined with struct shash_desc where the size of
797 * that data structure is to be calculated as
798 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
799 *
800 * Return: size of the operational state
801 */
802static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
803{
804 return tfm->descsize;
805}
806
807static inline void *shash_desc_ctx(struct shash_desc *desc)
808{
809 return desc->__ctx;
810}
811
812/**
813 * crypto_shash_setkey() - set key for message digest
814 * @tfm: cipher handle
815 * @key: buffer holding the key
816 * @keylen: length of the key in bytes
817 *
818 * The caller provided key is set for the keyed message digest cipher. The
819 * cipher handle must point to a keyed message digest cipher in order for this
820 * function to succeed.
821 *
822 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
823 */
824int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
825 unsigned int keylen);
826
827/**
828 * crypto_shash_digest() - calculate message digest for buffer
829 * @desc: see crypto_shash_final()
830 * @data: see crypto_shash_update()
831 * @len: see crypto_shash_update()
832 * @out: see crypto_shash_final()
833 *
834 * This function is a "short-hand" for the function calls of crypto_shash_init,
835 * crypto_shash_update and crypto_shash_final. The parameters have the same
836 * meaning as discussed for those separate three functions.
837 *
838 * Return: 0 if the message digest creation was successful; < 0 if an error
839 * occurred
840 */
841int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
842 unsigned int len, u8 *out);
843
844/**
845 * crypto_shash_export() - extract operational state for message digest
846 * @desc: reference to the operational state handle whose state is exported
847 * @out: output buffer of sufficient size that can hold the hash state
848 *
849 * This function exports the hash state of the operational state handle into the
850 * caller-allocated output buffer out which must have sufficient size (e.g. by
851 * calling crypto_shash_descsize).
852 *
853 * Return: 0 if the export creation was successful; < 0 if an error occurred
854 */
855static inline int crypto_shash_export(struct shash_desc *desc, void *out)
856{
857 return crypto_shash_alg(desc->tfm)->export(desc, out);
858}
859
860/**
861 * crypto_shash_import() - import operational state
862 * @desc: reference to the operational state handle the state imported into
863 * @in: buffer holding the state
864 *
865 * This function imports the hash state into the operational state handle from
866 * the input buffer. That buffer should have been generated with the
867 * crypto_ahash_export function.
868 *
869 * Return: 0 if the import was successful; < 0 if an error occurred
870 */
871static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
872{
873 struct crypto_shash *tfm = desc->tfm;
874
875 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
876 return -ENOKEY;
877
878 return crypto_shash_alg(tfm)->import(desc, in);
879}
880
881/**
882 * crypto_shash_init() - (re)initialize message digest
883 * @desc: operational state handle that is already filled
884 *
885 * The call (re-)initializes the message digest referenced by the
886 * operational state handle. Any potentially existing state created by
887 * previous operations is discarded.
888 *
889 * Return: 0 if the message digest initialization was successful; < 0 if an
890 * error occurred
891 */
892static inline int crypto_shash_init(struct shash_desc *desc)
893{
894 struct crypto_shash *tfm = desc->tfm;
895
896 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
897 return -ENOKEY;
898
899 return crypto_shash_alg(tfm)->init(desc);
900}
901
902/**
903 * crypto_shash_update() - add data to message digest for processing
904 * @desc: operational state handle that is already initialized
905 * @data: input data to be added to the message digest
906 * @len: length of the input data
907 *
908 * Updates the message digest state of the operational state handle.
909 *
910 * Return: 0 if the message digest update was successful; < 0 if an error
911 * occurred
912 */
913int crypto_shash_update(struct shash_desc *desc, const u8 *data,
914 unsigned int len);
915
916/**
917 * crypto_shash_final() - calculate message digest
918 * @desc: operational state handle that is already filled with data
919 * @out: output buffer filled with the message digest
920 *
921 * Finalize the message digest operation and create the message digest
922 * based on all data added to the cipher handle. The message digest is placed
923 * into the output buffer. The caller must ensure that the output buffer is
924 * large enough by using crypto_shash_digestsize.
925 *
926 * Return: 0 if the message digest creation was successful; < 0 if an error
927 * occurred
928 */
929int crypto_shash_final(struct shash_desc *desc, u8 *out);
930
931/**
932 * crypto_shash_finup() - calculate message digest of buffer
933 * @desc: see crypto_shash_final()
934 * @data: see crypto_shash_update()
935 * @len: see crypto_shash_update()
936 * @out: see crypto_shash_final()
937 *
938 * This function is a "short-hand" for the function calls of
939 * crypto_shash_update and crypto_shash_final. The parameters have the same
940 * meaning as discussed for those separate functions.
941 *
942 * Return: 0 if the message digest creation was successful; < 0 if an error
943 * occurred
944 */
945int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
946 unsigned int len, u8 *out);
947
948static inline void shash_desc_zero(struct shash_desc *desc)
949{
950 memzero_explicit(desc,
951 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
952}
953
954#endif /* _CRYPTO_HASH_H */
955