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