xref: /linux/include/crypto/hash.h (revision ae7d45fb7ca75e94b478e2404709ba3024774334)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Hash: Hash algorithms under the crypto API
4  *
5  * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
6  */
7 
8 #ifndef _CRYPTO_HASH_H
9 #define _CRYPTO_HASH_H
10 
11 #include <linux/atomic.h>
12 #include <linux/crypto.h>
13 #include <linux/string.h>
14 
15 struct crypto_ahash;
16 
17 /**
18  * DOC: Message Digest Algorithm Definitions
19  *
20  * These data structures define modular message digest algorithm
21  * implementations, managed via crypto_register_ahash(),
22  * crypto_register_shash(), crypto_unregister_ahash() and
23  * crypto_unregister_shash().
24  */
25 
26 /*
27  * struct crypto_istat_hash - statistics for has algorithm
28  * @hash_cnt:		number of hash requests
29  * @hash_tlen:		total data size hashed
30  * @err_cnt:		number of error for hash requests
31  */
32 struct crypto_istat_hash {
33 	atomic64_t hash_cnt;
34 	atomic64_t hash_tlen;
35 	atomic64_t err_cnt;
36 };
37 
38 #ifdef CONFIG_CRYPTO_STATS
39 #define HASH_ALG_COMMON_STAT struct crypto_istat_hash stat;
40 #else
41 #define HASH_ALG_COMMON_STAT
42 #endif
43 
44 /**
45  * struct hash_alg_common - define properties of message digest
46  * @stat: Statistics for hash algorithm.
47  * @digestsize: Size of the result of the transformation. A buffer of this size
48  *	        must be available to the @final and @finup calls, so they can
49  *	        store the resulting hash into it. For various predefined sizes,
50  *	        search include/crypto/ using
51  *	        git grep _DIGEST_SIZE include/crypto.
52  * @statesize: Size of the block for partial state of the transformation. A
53  *	       buffer of this size must be passed to the @export function as it
54  *	       will save the partial state of the transformation into it. On the
55  *	       other side, the @import function will load the state from a
56  *	       buffer of this size as well.
57  * @base: Start of data structure of cipher algorithm. The common data
58  *	  structure of crypto_alg contains information common to all ciphers.
59  *	  The hash_alg_common data structure now adds the hash-specific
60  *	  information.
61  */
62 #define HASH_ALG_COMMON {		\
63 	HASH_ALG_COMMON_STAT		\
64 					\
65 	unsigned int digestsize;	\
66 	unsigned int statesize;		\
67 					\
68 	struct crypto_alg base;		\
69 }
70 struct hash_alg_common HASH_ALG_COMMON;
71 
72 struct ahash_request {
73 	struct crypto_async_request base;
74 
75 	unsigned int nbytes;
76 	struct scatterlist *src;
77 	u8 *result;
78 
79 	/* This field may only be used by the ahash API code. */
80 	void *priv;
81 
82 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
83 };
84 
85 /**
86  * struct ahash_alg - asynchronous message digest definition
87  * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the
88  *	  state of the HASH transformation at the beginning. This shall fill in
89  *	  the internal structures used during the entire duration of the whole
90  *	  transformation. No data processing happens at this point. Driver code
91  *	  implementation must not use req->result.
92  * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
93  *	   function actually pushes blocks of data from upper layers into the
94  *	   driver, which then passes those to the hardware as seen fit. This
95  *	   function must not finalize the HASH transformation by calculating the
96  *	   final message digest as this only adds more data into the
97  *	   transformation. This function shall not modify the transformation
98  *	   context, as this function may be called in parallel with the same
99  *	   transformation object. Data processing can happen synchronously
100  *	   [SHASH] or asynchronously [AHASH] at this point. Driver must not use
101  *	   req->result.
102  * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
103  *	   transformation and retrieves the resulting hash from the driver and
104  *	   pushes it back to upper layers. No data processing happens at this
105  *	   point unless hardware requires it to finish the transformation
106  *	   (then the data buffered by the device driver is processed).
107  * @finup: **[optional]** Combination of @update and @final. This function is effectively a
108  *	   combination of @update and @final calls issued in sequence. As some
109  *	   hardware cannot do @update and @final separately, this callback was
110  *	   added to allow such hardware to be used at least by IPsec. Data
111  *	   processing can happen synchronously [SHASH] or asynchronously [AHASH]
112  *	   at this point.
113  * @digest: Combination of @init and @update and @final. This function
114  *	    effectively behaves as the entire chain of operations, @init,
115  *	    @update and @final issued in sequence. Just like @finup, this was
116  *	    added for hardware which cannot do even the @finup, but can only do
117  *	    the whole transformation in one run. Data processing can happen
118  *	    synchronously [SHASH] or asynchronously [AHASH] at this point.
119  * @setkey: Set optional key used by the hashing algorithm. Intended to push
120  *	    optional key used by the hashing algorithm from upper layers into
121  *	    the driver. This function can store the key in the transformation
122  *	    context or can outright program it into the hardware. In the former
123  *	    case, one must be careful to program the key into the hardware at
124  *	    appropriate time and one must be careful that .setkey() can be
125  *	    called multiple times during the existence of the transformation
126  *	    object. Not  all hashing algorithms do implement this function as it
127  *	    is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
128  *	    implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
129  *	    this function. This function must be called before any other of the
130  *	    @init, @update, @final, @finup, @digest is called. No data
131  *	    processing happens at this point.
132  * @export: Export partial state of the transformation. This function dumps the
133  *	    entire state of the ongoing transformation into a provided block of
134  *	    data so it can be @import 'ed back later on. This is useful in case
135  *	    you want to save partial result of the transformation after
136  *	    processing certain amount of data and reload this partial result
137  *	    multiple times later on for multiple re-use. No data processing
138  *	    happens at this point. Driver must not use req->result.
139  * @import: Import partial state of the transformation. This function loads the
140  *	    entire state of the ongoing transformation from a provided block of
141  *	    data so the transformation can continue from this point onward. No
142  *	    data processing happens at this point. Driver must not use
143  *	    req->result.
144  * @init_tfm: Initialize the cryptographic transformation object.
145  *	      This function is called only once at the instantiation
146  *	      time, right after the transformation context was
147  *	      allocated. In case the cryptographic hardware has
148  *	      some special requirements which need to be handled
149  *	      by software, this function shall check for the precise
150  *	      requirement of the transformation and put any software
151  *	      fallbacks in place.
152  * @exit_tfm: Deinitialize the cryptographic transformation object.
153  *	      This is a counterpart to @init_tfm, used to remove
154  *	      various changes set in @init_tfm.
155  * @halg: see struct hash_alg_common
156  */
157 struct ahash_alg {
158 	int (*init)(struct ahash_request *req);
159 	int (*update)(struct ahash_request *req);
160 	int (*final)(struct ahash_request *req);
161 	int (*finup)(struct ahash_request *req);
162 	int (*digest)(struct ahash_request *req);
163 	int (*export)(struct ahash_request *req, void *out);
164 	int (*import)(struct ahash_request *req, const void *in);
165 	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
166 		      unsigned int keylen);
167 	int (*init_tfm)(struct crypto_ahash *tfm);
168 	void (*exit_tfm)(struct crypto_ahash *tfm);
169 
170 	struct hash_alg_common halg;
171 };
172 
173 struct shash_desc {
174 	struct crypto_shash *tfm;
175 	void *__ctx[] __aligned(ARCH_SLAB_MINALIGN);
176 };
177 
178 #define HASH_MAX_DIGESTSIZE	 64
179 
180 /*
181  * Worst case is hmac(sha3-224-generic).  Its context is a nested 'shash_desc'
182  * containing a 'struct sha3_state'.
183  */
184 #define HASH_MAX_DESCSIZE	(sizeof(struct shash_desc) + 360)
185 
186 #define HASH_MAX_STATESIZE	512
187 
188 #define SHASH_DESC_ON_STACK(shash, ctx)					     \
189 	char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \
190 		__aligned(__alignof__(struct shash_desc));		     \
191 	struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
192 
193 /**
194  * struct shash_alg - synchronous message digest definition
195  * @init: see struct ahash_alg
196  * @update: see struct ahash_alg
197  * @final: see struct ahash_alg
198  * @finup: see struct ahash_alg
199  * @digest: see struct ahash_alg
200  * @export: see struct ahash_alg
201  * @import: see struct ahash_alg
202  * @setkey: see struct ahash_alg
203  * @init_tfm: Initialize the cryptographic transformation object.
204  *	      This function is called only once at the instantiation
205  *	      time, right after the transformation context was
206  *	      allocated. In case the cryptographic hardware has
207  *	      some special requirements which need to be handled
208  *	      by software, this function shall check for the precise
209  *	      requirement of the transformation and put any software
210  *	      fallbacks in place.
211  * @exit_tfm: Deinitialize the cryptographic transformation object.
212  *	      This is a counterpart to @init_tfm, used to remove
213  *	      various changes set in @init_tfm.
214  * @digestsize: see struct ahash_alg
215  * @statesize: see struct ahash_alg
216  * @descsize: Size of the operational state for the message digest. This state
217  * 	      size is the memory size that needs to be allocated for
218  *	      shash_desc.__ctx
219  * @stat: Statistics for hash algorithm.
220  * @base: internally used
221  * @halg: see struct hash_alg_common
222  */
223 struct shash_alg {
224 	int (*init)(struct shash_desc *desc);
225 	int (*update)(struct shash_desc *desc, const u8 *data,
226 		      unsigned int len);
227 	int (*final)(struct shash_desc *desc, u8 *out);
228 	int (*finup)(struct shash_desc *desc, const u8 *data,
229 		     unsigned int len, u8 *out);
230 	int (*digest)(struct shash_desc *desc, const u8 *data,
231 		      unsigned int len, u8 *out);
232 	int (*export)(struct shash_desc *desc, void *out);
233 	int (*import)(struct shash_desc *desc, const void *in);
234 	int (*setkey)(struct crypto_shash *tfm, const u8 *key,
235 		      unsigned int keylen);
236 	int (*init_tfm)(struct crypto_shash *tfm);
237 	void (*exit_tfm)(struct crypto_shash *tfm);
238 
239 	unsigned int descsize;
240 
241 	union {
242 		struct HASH_ALG_COMMON;
243 		struct hash_alg_common halg;
244 	};
245 };
246 #undef HASH_ALG_COMMON
247 #undef HASH_ALG_COMMON_STAT
248 
249 struct crypto_ahash {
250 	int (*init)(struct ahash_request *req);
251 	int (*update)(struct ahash_request *req);
252 	int (*final)(struct ahash_request *req);
253 	int (*finup)(struct ahash_request *req);
254 	int (*digest)(struct ahash_request *req);
255 	int (*export)(struct ahash_request *req, void *out);
256 	int (*import)(struct ahash_request *req, const void *in);
257 	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
258 		      unsigned int keylen);
259 
260 	unsigned int reqsize;
261 	struct crypto_tfm base;
262 };
263 
264 struct crypto_shash {
265 	unsigned int descsize;
266 	struct crypto_tfm base;
267 };
268 
269 /**
270  * DOC: Asynchronous Message Digest API
271  *
272  * The asynchronous message digest API is used with the ciphers of type
273  * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
274  *
275  * The asynchronous cipher operation discussion provided for the
276  * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well.
277  */
278 
279 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
280 {
281 	return container_of(tfm, struct crypto_ahash, base);
282 }
283 
284 /**
285  * crypto_alloc_ahash() - allocate ahash cipher handle
286  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
287  *	      ahash cipher
288  * @type: specifies the type of the cipher
289  * @mask: specifies the mask for the cipher
290  *
291  * Allocate a cipher handle for an ahash. The returned struct
292  * crypto_ahash is the cipher handle that is required for any subsequent
293  * API invocation for that ahash.
294  *
295  * Return: allocated cipher handle in case of success; IS_ERR() is true in case
296  *	   of an error, PTR_ERR() returns the error code.
297  */
298 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
299 					u32 mask);
300 
301 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
302 {
303 	return &tfm->base;
304 }
305 
306 /**
307  * crypto_free_ahash() - zeroize and free the ahash handle
308  * @tfm: cipher handle to be freed
309  *
310  * If @tfm is a NULL or error pointer, this function does nothing.
311  */
312 static inline void crypto_free_ahash(struct crypto_ahash *tfm)
313 {
314 	crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
315 }
316 
317 /**
318  * crypto_has_ahash() - Search for the availability of an ahash.
319  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
320  *	      ahash
321  * @type: specifies the type of the ahash
322  * @mask: specifies the mask for the ahash
323  *
324  * Return: true when the ahash is known to the kernel crypto API; false
325  *	   otherwise
326  */
327 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
328 
329 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
330 {
331 	return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
332 }
333 
334 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
335 {
336 	return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
337 }
338 
339 static inline unsigned int crypto_ahash_alignmask(
340 	struct crypto_ahash *tfm)
341 {
342 	return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
343 }
344 
345 /**
346  * crypto_ahash_blocksize() - obtain block size for cipher
347  * @tfm: cipher handle
348  *
349  * The block size for the message digest cipher referenced with the cipher
350  * handle is returned.
351  *
352  * Return: block size of cipher
353  */
354 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
355 {
356 	return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
357 }
358 
359 static inline struct hash_alg_common *__crypto_hash_alg_common(
360 	struct crypto_alg *alg)
361 {
362 	return container_of(alg, struct hash_alg_common, base);
363 }
364 
365 static inline struct hash_alg_common *crypto_hash_alg_common(
366 	struct crypto_ahash *tfm)
367 {
368 	return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
369 }
370 
371 /**
372  * crypto_ahash_digestsize() - obtain message digest size
373  * @tfm: cipher handle
374  *
375  * The size for the message digest created by the message digest cipher
376  * referenced with the cipher handle is returned.
377  *
378  *
379  * Return: message digest size of cipher
380  */
381 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
382 {
383 	return crypto_hash_alg_common(tfm)->digestsize;
384 }
385 
386 /**
387  * crypto_ahash_statesize() - obtain size of the ahash state
388  * @tfm: cipher handle
389  *
390  * Return the size of the ahash state. With the crypto_ahash_export()
391  * function, the caller can export the state into a buffer whose size is
392  * defined with this function.
393  *
394  * Return: size of the ahash state
395  */
396 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
397 {
398 	return crypto_hash_alg_common(tfm)->statesize;
399 }
400 
401 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
402 {
403 	return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
404 }
405 
406 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
407 {
408 	crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
409 }
410 
411 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
412 {
413 	crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
414 }
415 
416 /**
417  * crypto_ahash_reqtfm() - obtain cipher handle from request
418  * @req: asynchronous request handle that contains the reference to the ahash
419  *	 cipher handle
420  *
421  * Return the ahash cipher handle that is registered with the asynchronous
422  * request handle ahash_request.
423  *
424  * Return: ahash cipher handle
425  */
426 static inline struct crypto_ahash *crypto_ahash_reqtfm(
427 	struct ahash_request *req)
428 {
429 	return __crypto_ahash_cast(req->base.tfm);
430 }
431 
432 /**
433  * crypto_ahash_reqsize() - obtain size of the request data structure
434  * @tfm: cipher handle
435  *
436  * Return: size of the request data
437  */
438 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
439 {
440 	return tfm->reqsize;
441 }
442 
443 static inline void *ahash_request_ctx(struct ahash_request *req)
444 {
445 	return req->__ctx;
446 }
447 
448 /**
449  * crypto_ahash_setkey - set key for cipher handle
450  * @tfm: cipher handle
451  * @key: buffer holding the key
452  * @keylen: length of the key in bytes
453  *
454  * The caller provided key is set for the ahash cipher. The cipher
455  * handle must point to a keyed hash in order for this function to succeed.
456  *
457  * Return: 0 if the setting of the key was successful; < 0 if an error occurred
458  */
459 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
460 			unsigned int keylen);
461 
462 /**
463  * crypto_ahash_finup() - update and finalize message digest
464  * @req: reference to the ahash_request handle that holds all information
465  *	 needed to perform the cipher operation
466  *
467  * This function is a "short-hand" for the function calls of
468  * crypto_ahash_update and crypto_ahash_final. The parameters have the same
469  * meaning as discussed for those separate functions.
470  *
471  * Return: see crypto_ahash_final()
472  */
473 int crypto_ahash_finup(struct ahash_request *req);
474 
475 /**
476  * crypto_ahash_final() - calculate message digest
477  * @req: reference to the ahash_request handle that holds all information
478  *	 needed to perform the cipher operation
479  *
480  * Finalize the message digest operation and create the message digest
481  * based on all data added to the cipher handle. The message digest is placed
482  * into the output buffer registered with the ahash_request handle.
483  *
484  * Return:
485  * 0		if the message digest was successfully calculated;
486  * -EINPROGRESS	if data is fed into hardware (DMA) or queued for later;
487  * -EBUSY	if queue is full and request should be resubmitted later;
488  * other < 0	if an error occurred
489  */
490 int crypto_ahash_final(struct ahash_request *req);
491 
492 /**
493  * crypto_ahash_digest() - calculate message digest for a buffer
494  * @req: reference to the ahash_request handle that holds all information
495  *	 needed to perform the cipher operation
496  *
497  * This function is a "short-hand" for the function calls of crypto_ahash_init,
498  * crypto_ahash_update and crypto_ahash_final. The parameters have the same
499  * meaning as discussed for those separate three functions.
500  *
501  * Return: see crypto_ahash_final()
502  */
503 int crypto_ahash_digest(struct ahash_request *req);
504 
505 /**
506  * crypto_ahash_export() - extract current message digest state
507  * @req: reference to the ahash_request handle whose state is exported
508  * @out: output buffer of sufficient size that can hold the hash state
509  *
510  * This function exports the hash state of the ahash_request handle into the
511  * caller-allocated output buffer out which must have sufficient size (e.g. by
512  * calling crypto_ahash_statesize()).
513  *
514  * Return: 0 if the export was successful; < 0 if an error occurred
515  */
516 static inline int crypto_ahash_export(struct ahash_request *req, void *out)
517 {
518 	return crypto_ahash_reqtfm(req)->export(req, out);
519 }
520 
521 /**
522  * crypto_ahash_import() - import message digest state
523  * @req: reference to ahash_request handle the state is imported into
524  * @in: buffer holding the state
525  *
526  * This function imports the hash state into the ahash_request handle from the
527  * input buffer. That buffer should have been generated with the
528  * crypto_ahash_export function.
529  *
530  * Return: 0 if the import was successful; < 0 if an error occurred
531  */
532 static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
533 {
534 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
535 
536 	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
537 		return -ENOKEY;
538 
539 	return tfm->import(req, in);
540 }
541 
542 /**
543  * crypto_ahash_init() - (re)initialize message digest handle
544  * @req: ahash_request handle that already is initialized with all necessary
545  *	 data using the ahash_request_* API functions
546  *
547  * The call (re-)initializes the message digest referenced by the ahash_request
548  * handle. Any potentially existing state created by previous operations is
549  * discarded.
550  *
551  * Return: see crypto_ahash_final()
552  */
553 static inline int crypto_ahash_init(struct ahash_request *req)
554 {
555 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
556 
557 	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
558 		return -ENOKEY;
559 
560 	return tfm->init(req);
561 }
562 
563 static inline struct crypto_istat_hash *hash_get_stat(
564 	struct hash_alg_common *alg)
565 {
566 #ifdef CONFIG_CRYPTO_STATS
567 	return &alg->stat;
568 #else
569 	return NULL;
570 #endif
571 }
572 
573 static inline int crypto_hash_errstat(struct hash_alg_common *alg, int err)
574 {
575 	if (!IS_ENABLED(CONFIG_CRYPTO_STATS))
576 		return err;
577 
578 	if (err && err != -EINPROGRESS && err != -EBUSY)
579 		atomic64_inc(&hash_get_stat(alg)->err_cnt);
580 
581 	return err;
582 }
583 
584 /**
585  * crypto_ahash_update() - add data to message digest for processing
586  * @req: ahash_request handle that was previously initialized with the
587  *	 crypto_ahash_init call.
588  *
589  * Updates the message digest state of the &ahash_request handle. The input data
590  * is pointed to by the scatter/gather list registered in the &ahash_request
591  * handle
592  *
593  * Return: see crypto_ahash_final()
594  */
595 static inline int crypto_ahash_update(struct ahash_request *req)
596 {
597 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
598 	struct hash_alg_common *alg = crypto_hash_alg_common(tfm);
599 
600 	if (IS_ENABLED(CONFIG_CRYPTO_STATS))
601 		atomic64_add(req->nbytes, &hash_get_stat(alg)->hash_tlen);
602 
603 	return crypto_hash_errstat(alg, tfm->update(req));
604 }
605 
606 /**
607  * DOC: Asynchronous Hash Request Handle
608  *
609  * The &ahash_request data structure contains all pointers to data
610  * required for the asynchronous cipher operation. This includes the cipher
611  * handle (which can be used by multiple &ahash_request instances), pointer
612  * to plaintext and the message digest output buffer, asynchronous callback
613  * function, etc. It acts as a handle to the ahash_request_* API calls in a
614  * similar way as ahash handle to the crypto_ahash_* API calls.
615  */
616 
617 /**
618  * ahash_request_set_tfm() - update cipher handle reference in request
619  * @req: request handle to be modified
620  * @tfm: cipher handle that shall be added to the request handle
621  *
622  * Allow the caller to replace the existing ahash handle in the request
623  * data structure with a different one.
624  */
625 static inline void ahash_request_set_tfm(struct ahash_request *req,
626 					 struct crypto_ahash *tfm)
627 {
628 	req->base.tfm = crypto_ahash_tfm(tfm);
629 }
630 
631 /**
632  * ahash_request_alloc() - allocate request data structure
633  * @tfm: cipher handle to be registered with the request
634  * @gfp: memory allocation flag that is handed to kmalloc by the API call.
635  *
636  * Allocate the request data structure that must be used with the ahash
637  * message digest API calls. During
638  * the allocation, the provided ahash handle
639  * is registered in the request data structure.
640  *
641  * Return: allocated request handle in case of success, or NULL if out of memory
642  */
643 static inline struct ahash_request *ahash_request_alloc(
644 	struct crypto_ahash *tfm, gfp_t gfp)
645 {
646 	struct ahash_request *req;
647 
648 	req = kmalloc(sizeof(struct ahash_request) +
649 		      crypto_ahash_reqsize(tfm), gfp);
650 
651 	if (likely(req))
652 		ahash_request_set_tfm(req, tfm);
653 
654 	return req;
655 }
656 
657 /**
658  * ahash_request_free() - zeroize and free the request data structure
659  * @req: request data structure cipher handle to be freed
660  */
661 static inline void ahash_request_free(struct ahash_request *req)
662 {
663 	kfree_sensitive(req);
664 }
665 
666 static inline void ahash_request_zero(struct ahash_request *req)
667 {
668 	memzero_explicit(req, sizeof(*req) +
669 			      crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
670 }
671 
672 static inline struct ahash_request *ahash_request_cast(
673 	struct crypto_async_request *req)
674 {
675 	return container_of(req, struct ahash_request, base);
676 }
677 
678 /**
679  * ahash_request_set_callback() - set asynchronous callback function
680  * @req: request handle
681  * @flags: specify zero or an ORing of the flags
682  *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
683  *	   increase the wait queue beyond the initial maximum size;
684  *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
685  * @compl: callback function pointer to be registered with the request handle
686  * @data: The data pointer refers to memory that is not used by the kernel
687  *	  crypto API, but provided to the callback function for it to use. Here,
688  *	  the caller can provide a reference to memory the callback function can
689  *	  operate on. As the callback function is invoked asynchronously to the
690  *	  related functionality, it may need to access data structures of the
691  *	  related functionality which can be referenced using this pointer. The
692  *	  callback function can access the memory via the "data" field in the
693  *	  &crypto_async_request data structure provided to the callback function.
694  *
695  * This function allows setting the callback function that is triggered once
696  * the cipher operation completes.
697  *
698  * The callback function is registered with the &ahash_request handle and
699  * must comply with the following template::
700  *
701  *	void callback_function(struct crypto_async_request *req, int error)
702  */
703 static inline void ahash_request_set_callback(struct ahash_request *req,
704 					      u32 flags,
705 					      crypto_completion_t compl,
706 					      void *data)
707 {
708 	req->base.complete = compl;
709 	req->base.data = data;
710 	req->base.flags = flags;
711 }
712 
713 /**
714  * ahash_request_set_crypt() - set data buffers
715  * @req: ahash_request handle to be updated
716  * @src: source scatter/gather list
717  * @result: buffer that is filled with the message digest -- the caller must
718  *	    ensure that the buffer has sufficient space by, for example, calling
719  *	    crypto_ahash_digestsize()
720  * @nbytes: number of bytes to process from the source scatter/gather list
721  *
722  * By using this call, the caller references the source scatter/gather list.
723  * The source scatter/gather list points to the data the message digest is to
724  * be calculated for.
725  */
726 static inline void ahash_request_set_crypt(struct ahash_request *req,
727 					   struct scatterlist *src, u8 *result,
728 					   unsigned int nbytes)
729 {
730 	req->src = src;
731 	req->nbytes = nbytes;
732 	req->result = result;
733 }
734 
735 /**
736  * DOC: Synchronous Message Digest API
737  *
738  * The synchronous message digest API is used with the ciphers of type
739  * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
740  *
741  * The message digest API is able to maintain state information for the
742  * caller.
743  *
744  * The synchronous message digest API can store user-related context in its
745  * shash_desc request data structure.
746  */
747 
748 /**
749  * crypto_alloc_shash() - allocate message digest handle
750  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
751  *	      message digest cipher
752  * @type: specifies the type of the cipher
753  * @mask: specifies the mask for the cipher
754  *
755  * Allocate a cipher handle for a message digest. The returned &struct
756  * crypto_shash is the cipher handle that is required for any subsequent
757  * API invocation for that message digest.
758  *
759  * Return: allocated cipher handle in case of success; IS_ERR() is true in case
760  *	   of an error, PTR_ERR() returns the error code.
761  */
762 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
763 					u32 mask);
764 
765 int crypto_has_shash(const char *alg_name, u32 type, u32 mask);
766 
767 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
768 {
769 	return &tfm->base;
770 }
771 
772 /**
773  * crypto_free_shash() - zeroize and free the message digest handle
774  * @tfm: cipher handle to be freed
775  *
776  * If @tfm is a NULL or error pointer, this function does nothing.
777  */
778 static inline void crypto_free_shash(struct crypto_shash *tfm)
779 {
780 	crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
781 }
782 
783 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
784 {
785 	return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
786 }
787 
788 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
789 {
790 	return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
791 }
792 
793 static inline unsigned int crypto_shash_alignmask(
794 	struct crypto_shash *tfm)
795 {
796 	return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
797 }
798 
799 /**
800  * crypto_shash_blocksize() - obtain block size for cipher
801  * @tfm: cipher handle
802  *
803  * The block size for the message digest cipher referenced with the cipher
804  * handle is returned.
805  *
806  * Return: block size of cipher
807  */
808 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
809 {
810 	return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
811 }
812 
813 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
814 {
815 	return container_of(alg, struct shash_alg, base);
816 }
817 
818 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
819 {
820 	return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
821 }
822 
823 /**
824  * crypto_shash_digestsize() - obtain message digest size
825  * @tfm: cipher handle
826  *
827  * The size for the message digest created by the message digest cipher
828  * referenced with the cipher handle is returned.
829  *
830  * Return: digest size of cipher
831  */
832 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
833 {
834 	return crypto_shash_alg(tfm)->digestsize;
835 }
836 
837 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
838 {
839 	return crypto_shash_alg(tfm)->statesize;
840 }
841 
842 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
843 {
844 	return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
845 }
846 
847 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
848 {
849 	crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
850 }
851 
852 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
853 {
854 	crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
855 }
856 
857 /**
858  * crypto_shash_descsize() - obtain the operational state size
859  * @tfm: cipher handle
860  *
861  * The size of the operational state the cipher needs during operation is
862  * returned for the hash referenced with the cipher handle. This size is
863  * required to calculate the memory requirements to allow the caller allocating
864  * sufficient memory for operational state.
865  *
866  * The operational state is defined with struct shash_desc where the size of
867  * that data structure is to be calculated as
868  * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
869  *
870  * Return: size of the operational state
871  */
872 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
873 {
874 	return tfm->descsize;
875 }
876 
877 static inline void *shash_desc_ctx(struct shash_desc *desc)
878 {
879 	return desc->__ctx;
880 }
881 
882 /**
883  * crypto_shash_setkey() - set key for message digest
884  * @tfm: cipher handle
885  * @key: buffer holding the key
886  * @keylen: length of the key in bytes
887  *
888  * The caller provided key is set for the keyed message digest cipher. The
889  * cipher handle must point to a keyed message digest cipher in order for this
890  * function to succeed.
891  *
892  * Context: Any context.
893  * Return: 0 if the setting of the key was successful; < 0 if an error occurred
894  */
895 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
896 			unsigned int keylen);
897 
898 /**
899  * crypto_shash_digest() - calculate message digest for buffer
900  * @desc: see crypto_shash_final()
901  * @data: see crypto_shash_update()
902  * @len: see crypto_shash_update()
903  * @out: see crypto_shash_final()
904  *
905  * This function is a "short-hand" for the function calls of crypto_shash_init,
906  * crypto_shash_update and crypto_shash_final. The parameters have the same
907  * meaning as discussed for those separate three functions.
908  *
909  * Context: Any context.
910  * Return: 0 if the message digest creation was successful; < 0 if an error
911  *	   occurred
912  */
913 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
914 			unsigned int len, u8 *out);
915 
916 /**
917  * crypto_shash_tfm_digest() - calculate message digest for buffer
918  * @tfm: hash transformation object
919  * @data: see crypto_shash_update()
920  * @len: see crypto_shash_update()
921  * @out: see crypto_shash_final()
922  *
923  * This is a simplified version of crypto_shash_digest() for users who don't
924  * want to allocate their own hash descriptor (shash_desc).  Instead,
925  * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash)
926  * directly, and it allocates a hash descriptor on the stack internally.
927  * Note that this stack allocation may be fairly large.
928  *
929  * Context: Any context.
930  * Return: 0 on success; < 0 if an error occurred.
931  */
932 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
933 			    unsigned int len, u8 *out);
934 
935 /**
936  * crypto_shash_export() - extract operational state for message digest
937  * @desc: reference to the operational state handle whose state is exported
938  * @out: output buffer of sufficient size that can hold the hash state
939  *
940  * This function exports the hash state of the operational state handle into the
941  * caller-allocated output buffer out which must have sufficient size (e.g. by
942  * calling crypto_shash_descsize).
943  *
944  * Context: Any context.
945  * Return: 0 if the export creation was successful; < 0 if an error occurred
946  */
947 static inline int crypto_shash_export(struct shash_desc *desc, void *out)
948 {
949 	return crypto_shash_alg(desc->tfm)->export(desc, out);
950 }
951 
952 /**
953  * crypto_shash_import() - import operational state
954  * @desc: reference to the operational state handle the state imported into
955  * @in: buffer holding the state
956  *
957  * This function imports the hash state into the operational state handle from
958  * the input buffer. That buffer should have been generated with the
959  * crypto_ahash_export function.
960  *
961  * Context: Any context.
962  * Return: 0 if the import was successful; < 0 if an error occurred
963  */
964 static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
965 {
966 	struct crypto_shash *tfm = desc->tfm;
967 
968 	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
969 		return -ENOKEY;
970 
971 	return crypto_shash_alg(tfm)->import(desc, in);
972 }
973 
974 /**
975  * crypto_shash_init() - (re)initialize message digest
976  * @desc: operational state handle that is already filled
977  *
978  * The call (re-)initializes the message digest referenced by the
979  * operational state handle. Any potentially existing state created by
980  * previous operations is discarded.
981  *
982  * Context: Any context.
983  * Return: 0 if the message digest initialization was successful; < 0 if an
984  *	   error occurred
985  */
986 static inline int crypto_shash_init(struct shash_desc *desc)
987 {
988 	struct crypto_shash *tfm = desc->tfm;
989 
990 	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
991 		return -ENOKEY;
992 
993 	return crypto_shash_alg(tfm)->init(desc);
994 }
995 
996 /**
997  * crypto_shash_update() - add data to message digest for processing
998  * @desc: operational state handle that is already initialized
999  * @data: input data to be added to the message digest
1000  * @len: length of the input data
1001  *
1002  * Updates the message digest state of the operational state handle.
1003  *
1004  * Context: Any context.
1005  * Return: 0 if the message digest update was successful; < 0 if an error
1006  *	   occurred
1007  */
1008 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
1009 			unsigned int len);
1010 
1011 /**
1012  * crypto_shash_final() - calculate message digest
1013  * @desc: operational state handle that is already filled with data
1014  * @out: output buffer filled with the message digest
1015  *
1016  * Finalize the message digest operation and create the message digest
1017  * based on all data added to the cipher handle. The message digest is placed
1018  * into the output buffer. The caller must ensure that the output buffer is
1019  * large enough by using crypto_shash_digestsize.
1020  *
1021  * Context: Any context.
1022  * Return: 0 if the message digest creation was successful; < 0 if an error
1023  *	   occurred
1024  */
1025 int crypto_shash_final(struct shash_desc *desc, u8 *out);
1026 
1027 /**
1028  * crypto_shash_finup() - calculate message digest of buffer
1029  * @desc: see crypto_shash_final()
1030  * @data: see crypto_shash_update()
1031  * @len: see crypto_shash_update()
1032  * @out: see crypto_shash_final()
1033  *
1034  * This function is a "short-hand" for the function calls of
1035  * crypto_shash_update and crypto_shash_final. The parameters have the same
1036  * meaning as discussed for those separate functions.
1037  *
1038  * Context: Any context.
1039  * Return: 0 if the message digest creation was successful; < 0 if an error
1040  *	   occurred
1041  */
1042 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
1043 		       unsigned int len, u8 *out);
1044 
1045 static inline void shash_desc_zero(struct shash_desc *desc)
1046 {
1047 	memzero_explicit(desc,
1048 			 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
1049 }
1050 
1051 #endif	/* _CRYPTO_HASH_H */
1052