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 
19 struct 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  */
47 struct hash_alg_common {
48 	unsigned int digestsize;
49 	unsigned int statesize;
50 
51 	struct crypto_alg base;
52 };
53 
54 struct 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  */
133 struct 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 
147 struct shash_desc {
148 	struct crypto_shash *tfm;
149 	u32 flags;
150 
151 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
152 };
153 
154 #define SHASH_DESC_ON_STACK(shash, ctx)				  \
155 	char __##shash##_desc[sizeof(struct shash_desc) +	  \
156 		crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
157 	struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
158 
159 /**
160  * struct shash_alg - synchronous message digest definition
161  * @init: see struct ahash_alg
162  * @update: see struct ahash_alg
163  * @final: see struct ahash_alg
164  * @finup: see struct ahash_alg
165  * @digest: see struct ahash_alg
166  * @export: see struct ahash_alg
167  * @import: see struct ahash_alg
168  * @setkey: see struct ahash_alg
169  * @digestsize: see struct ahash_alg
170  * @statesize: see struct ahash_alg
171  * @descsize: Size of the operational state for the message digest. This state
172  * 	      size is the memory size that needs to be allocated for
173  *	      shash_desc.__ctx
174  * @base: internally used
175  */
176 struct shash_alg {
177 	int (*init)(struct shash_desc *desc);
178 	int (*update)(struct shash_desc *desc, const u8 *data,
179 		      unsigned int len);
180 	int (*final)(struct shash_desc *desc, u8 *out);
181 	int (*finup)(struct shash_desc *desc, const u8 *data,
182 		     unsigned int len, u8 *out);
183 	int (*digest)(struct shash_desc *desc, const u8 *data,
184 		      unsigned int len, u8 *out);
185 	int (*export)(struct shash_desc *desc, void *out);
186 	int (*import)(struct shash_desc *desc, const void *in);
187 	int (*setkey)(struct crypto_shash *tfm, const u8 *key,
188 		      unsigned int keylen);
189 
190 	unsigned int descsize;
191 
192 	/* These fields must match hash_alg_common. */
193 	unsigned int digestsize
194 		__attribute__ ((aligned(__alignof__(struct hash_alg_common))));
195 	unsigned int statesize;
196 
197 	struct crypto_alg base;
198 };
199 
200 struct crypto_ahash {
201 	int (*init)(struct ahash_request *req);
202 	int (*update)(struct ahash_request *req);
203 	int (*final)(struct ahash_request *req);
204 	int (*finup)(struct ahash_request *req);
205 	int (*digest)(struct ahash_request *req);
206 	int (*export)(struct ahash_request *req, void *out);
207 	int (*import)(struct ahash_request *req, const void *in);
208 	int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
209 		      unsigned int keylen);
210 
211 	unsigned int reqsize;
212 	struct crypto_tfm base;
213 };
214 
215 struct crypto_shash {
216 	unsigned int descsize;
217 	struct crypto_tfm base;
218 };
219 
220 /**
221  * DOC: Asynchronous Message Digest API
222  *
223  * The asynchronous message digest API is used with the ciphers of type
224  * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
225  *
226  * The asynchronous cipher operation discussion provided for the
227  * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well.
228  */
229 
__crypto_ahash_cast(struct crypto_tfm * tfm)230 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
231 {
232 	return container_of(tfm, struct crypto_ahash, base);
233 }
234 
235 /**
236  * crypto_alloc_ahash() - allocate ahash cipher handle
237  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
238  *	      ahash cipher
239  * @type: specifies the type of the cipher
240  * @mask: specifies the mask for the cipher
241  *
242  * Allocate a cipher handle for an ahash. The returned struct
243  * crypto_ahash is the cipher handle that is required for any subsequent
244  * API invocation for that ahash.
245  *
246  * Return: allocated cipher handle in case of success; IS_ERR() is true in case
247  *	   of an error, PTR_ERR() returns the error code.
248  */
249 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
250 					u32 mask);
251 
crypto_ahash_tfm(struct crypto_ahash * tfm)252 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
253 {
254 	return &tfm->base;
255 }
256 
257 /**
258  * crypto_free_ahash() - zeroize and free the ahash handle
259  * @tfm: cipher handle to be freed
260  *
261  * If @tfm is a NULL or error pointer, this function does nothing.
262  */
crypto_free_ahash(struct crypto_ahash * tfm)263 static inline void crypto_free_ahash(struct crypto_ahash *tfm)
264 {
265 	crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
266 }
267 
268 /**
269  * crypto_has_ahash() - Search for the availability of an ahash.
270  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
271  *	      ahash
272  * @type: specifies the type of the ahash
273  * @mask: specifies the mask for the ahash
274  *
275  * Return: true when the ahash is known to the kernel crypto API; false
276  *	   otherwise
277  */
278 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
279 
crypto_ahash_alg_name(struct crypto_ahash * tfm)280 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
281 {
282 	return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
283 }
284 
crypto_ahash_driver_name(struct crypto_ahash * tfm)285 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
286 {
287 	return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
288 }
289 
crypto_ahash_alignmask(struct crypto_ahash * tfm)290 static inline unsigned int crypto_ahash_alignmask(
291 	struct crypto_ahash *tfm)
292 {
293 	return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
294 }
295 
296 /**
297  * crypto_ahash_blocksize() - obtain block size for cipher
298  * @tfm: cipher handle
299  *
300  * The block size for the message digest cipher referenced with the cipher
301  * handle is returned.
302  *
303  * Return: block size of cipher
304  */
crypto_ahash_blocksize(struct crypto_ahash * tfm)305 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
306 {
307 	return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
308 }
309 
__crypto_hash_alg_common(struct crypto_alg * alg)310 static inline struct hash_alg_common *__crypto_hash_alg_common(
311 	struct crypto_alg *alg)
312 {
313 	return container_of(alg, struct hash_alg_common, base);
314 }
315 
crypto_hash_alg_common(struct crypto_ahash * tfm)316 static inline struct hash_alg_common *crypto_hash_alg_common(
317 	struct crypto_ahash *tfm)
318 {
319 	return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
320 }
321 
322 /**
323  * crypto_ahash_digestsize() - obtain message digest size
324  * @tfm: cipher handle
325  *
326  * The size for the message digest created by the message digest cipher
327  * referenced with the cipher handle is returned.
328  *
329  *
330  * Return: message digest size of cipher
331  */
crypto_ahash_digestsize(struct crypto_ahash * tfm)332 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
333 {
334 	return crypto_hash_alg_common(tfm)->digestsize;
335 }
336 
337 /**
338  * crypto_ahash_statesize() - obtain size of the ahash state
339  * @tfm: cipher handle
340  *
341  * Return the size of the ahash state. With the crypto_ahash_export()
342  * function, the caller can export the state into a buffer whose size is
343  * defined with this function.
344  *
345  * Return: size of the ahash state
346  */
crypto_ahash_statesize(struct crypto_ahash * tfm)347 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
348 {
349 	return crypto_hash_alg_common(tfm)->statesize;
350 }
351 
crypto_ahash_get_flags(struct crypto_ahash * tfm)352 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
353 {
354 	return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
355 }
356 
crypto_ahash_set_flags(struct crypto_ahash * tfm,u32 flags)357 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
358 {
359 	crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
360 }
361 
crypto_ahash_clear_flags(struct crypto_ahash * tfm,u32 flags)362 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
363 {
364 	crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
365 }
366 
367 /**
368  * crypto_ahash_reqtfm() - obtain cipher handle from request
369  * @req: asynchronous request handle that contains the reference to the ahash
370  *	 cipher handle
371  *
372  * Return the ahash cipher handle that is registered with the asynchronous
373  * request handle ahash_request.
374  *
375  * Return: ahash cipher handle
376  */
crypto_ahash_reqtfm(struct ahash_request * req)377 static inline struct crypto_ahash *crypto_ahash_reqtfm(
378 	struct ahash_request *req)
379 {
380 	return __crypto_ahash_cast(req->base.tfm);
381 }
382 
383 /**
384  * crypto_ahash_reqsize() - obtain size of the request data structure
385  * @tfm: cipher handle
386  *
387  * Return: size of the request data
388  */
crypto_ahash_reqsize(struct crypto_ahash * tfm)389 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
390 {
391 	return tfm->reqsize;
392 }
393 
ahash_request_ctx(struct ahash_request * req)394 static inline void *ahash_request_ctx(struct ahash_request *req)
395 {
396 	return req->__ctx;
397 }
398 
399 /**
400  * crypto_ahash_setkey - set key for cipher handle
401  * @tfm: cipher handle
402  * @key: buffer holding the key
403  * @keylen: length of the key in bytes
404  *
405  * The caller provided key is set for the ahash cipher. The cipher
406  * handle must point to a keyed hash in order for this function to succeed.
407  *
408  * Return: 0 if the setting of the key was successful; < 0 if an error occurred
409  */
410 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
411 			unsigned int keylen);
412 
413 /**
414  * crypto_ahash_finup() - update and finalize message digest
415  * @req: reference to the ahash_request handle that holds all information
416  *	 needed to perform the cipher operation
417  *
418  * This function is a "short-hand" for the function calls of
419  * crypto_ahash_update and crypto_ahash_final. The parameters have the same
420  * meaning as discussed for those separate functions.
421  *
422  * Return: see crypto_ahash_final()
423  */
424 int crypto_ahash_finup(struct ahash_request *req);
425 
426 /**
427  * crypto_ahash_final() - calculate message digest
428  * @req: reference to the ahash_request handle that holds all information
429  *	 needed to perform the cipher operation
430  *
431  * Finalize the message digest operation and create the message digest
432  * based on all data added to the cipher handle. The message digest is placed
433  * into the output buffer registered with the ahash_request handle.
434  *
435  * Return:
436  * 0		if the message digest was successfully calculated;
437  * -EINPROGRESS	if data is feeded into hardware (DMA) or queued for later;
438  * -EBUSY	if queue is full and request should be resubmitted later;
439  * other < 0	if an error occurred
440  */
441 int crypto_ahash_final(struct ahash_request *req);
442 
443 /**
444  * crypto_ahash_digest() - calculate message digest for a buffer
445  * @req: reference to the ahash_request handle that holds all information
446  *	 needed to perform the cipher operation
447  *
448  * This function is a "short-hand" for the function calls of crypto_ahash_init,
449  * crypto_ahash_update and crypto_ahash_final. The parameters have the same
450  * meaning as discussed for those separate three functions.
451  *
452  * Return: see crypto_ahash_final()
453  */
454 int crypto_ahash_digest(struct ahash_request *req);
455 
456 /**
457  * crypto_ahash_export() - extract current message digest state
458  * @req: reference to the ahash_request handle whose state is exported
459  * @out: output buffer of sufficient size that can hold the hash state
460  *
461  * This function exports the hash state of the ahash_request handle into the
462  * caller-allocated output buffer out which must have sufficient size (e.g. by
463  * calling crypto_ahash_statesize()).
464  *
465  * Return: 0 if the export was successful; < 0 if an error occurred
466  */
crypto_ahash_export(struct ahash_request * req,void * out)467 static inline int crypto_ahash_export(struct ahash_request *req, void *out)
468 {
469 	return crypto_ahash_reqtfm(req)->export(req, out);
470 }
471 
472 /**
473  * crypto_ahash_import() - import message digest state
474  * @req: reference to ahash_request handle the state is imported into
475  * @in: buffer holding the state
476  *
477  * This function imports the hash state into the ahash_request handle from the
478  * input buffer. That buffer should have been generated with the
479  * crypto_ahash_export function.
480  *
481  * Return: 0 if the import was successful; < 0 if an error occurred
482  */
crypto_ahash_import(struct ahash_request * req,const void * in)483 static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
484 {
485 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
486 
487 	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
488 		return -ENOKEY;
489 
490 	return tfm->import(req, in);
491 }
492 
493 /**
494  * crypto_ahash_init() - (re)initialize message digest handle
495  * @req: ahash_request handle that already is initialized with all necessary
496  *	 data using the ahash_request_* API functions
497  *
498  * The call (re-)initializes the message digest referenced by the ahash_request
499  * handle. Any potentially existing state created by previous operations is
500  * discarded.
501  *
502  * Return: see crypto_ahash_final()
503  */
crypto_ahash_init(struct ahash_request * req)504 static inline int crypto_ahash_init(struct ahash_request *req)
505 {
506 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
507 
508 	if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
509 		return -ENOKEY;
510 
511 	return tfm->init(req);
512 }
513 
514 /**
515  * crypto_ahash_update() - add data to message digest for processing
516  * @req: ahash_request handle that was previously initialized with the
517  *	 crypto_ahash_init call.
518  *
519  * Updates the message digest state of the &ahash_request handle. The input data
520  * is pointed to by the scatter/gather list registered in the &ahash_request
521  * handle
522  *
523  * Return: see crypto_ahash_final()
524  */
crypto_ahash_update(struct ahash_request * req)525 static inline int crypto_ahash_update(struct ahash_request *req)
526 {
527 	return crypto_ahash_reqtfm(req)->update(req);
528 }
529 
530 /**
531  * DOC: Asynchronous Hash Request Handle
532  *
533  * The &ahash_request data structure contains all pointers to data
534  * required for the asynchronous cipher operation. This includes the cipher
535  * handle (which can be used by multiple &ahash_request instances), pointer
536  * to plaintext and the message digest output buffer, asynchronous callback
537  * function, etc. It acts as a handle to the ahash_request_* API calls in a
538  * similar way as ahash handle to the crypto_ahash_* API calls.
539  */
540 
541 /**
542  * ahash_request_set_tfm() - update cipher handle reference in request
543  * @req: request handle to be modified
544  * @tfm: cipher handle that shall be added to the request handle
545  *
546  * Allow the caller to replace the existing ahash handle in the request
547  * data structure with a different one.
548  */
ahash_request_set_tfm(struct ahash_request * req,struct crypto_ahash * tfm)549 static inline void ahash_request_set_tfm(struct ahash_request *req,
550 					 struct crypto_ahash *tfm)
551 {
552 	req->base.tfm = crypto_ahash_tfm(tfm);
553 }
554 
555 /**
556  * ahash_request_alloc() - allocate request data structure
557  * @tfm: cipher handle to be registered with the request
558  * @gfp: memory allocation flag that is handed to kmalloc by the API call.
559  *
560  * Allocate the request data structure that must be used with the ahash
561  * message digest API calls. During
562  * the allocation, the provided ahash handle
563  * is registered in the request data structure.
564  *
565  * Return: allocated request handle in case of success, or NULL if out of memory
566  */
ahash_request_alloc(struct crypto_ahash * tfm,gfp_t gfp)567 static inline struct ahash_request *ahash_request_alloc(
568 	struct crypto_ahash *tfm, gfp_t gfp)
569 {
570 	struct ahash_request *req;
571 
572 	req = kmalloc(sizeof(struct ahash_request) +
573 		      crypto_ahash_reqsize(tfm), gfp);
574 
575 	if (likely(req))
576 		ahash_request_set_tfm(req, tfm);
577 
578 	return req;
579 }
580 
581 /**
582  * ahash_request_free() - zeroize and free the request data structure
583  * @req: request data structure cipher handle to be freed
584  */
ahash_request_free(struct ahash_request * req)585 static inline void ahash_request_free(struct ahash_request *req)
586 {
587 	kzfree(req);
588 }
589 
ahash_request_zero(struct ahash_request * req)590 static inline void ahash_request_zero(struct ahash_request *req)
591 {
592 	memzero_explicit(req, sizeof(*req) +
593 			      crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
594 }
595 
ahash_request_cast(struct crypto_async_request * req)596 static inline struct ahash_request *ahash_request_cast(
597 	struct crypto_async_request *req)
598 {
599 	return container_of(req, struct ahash_request, base);
600 }
601 
602 /**
603  * ahash_request_set_callback() - set asynchronous callback function
604  * @req: request handle
605  * @flags: specify zero or an ORing of the flags
606  *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
607  *	   increase the wait queue beyond the initial maximum size;
608  *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
609  * @compl: callback function pointer to be registered with the request handle
610  * @data: The data pointer refers to memory that is not used by the kernel
611  *	  crypto API, but provided to the callback function for it to use. Here,
612  *	  the caller can provide a reference to memory the callback function can
613  *	  operate on. As the callback function is invoked asynchronously to the
614  *	  related functionality, it may need to access data structures of the
615  *	  related functionality which can be referenced using this pointer. The
616  *	  callback function can access the memory via the "data" field in the
617  *	  &crypto_async_request data structure provided to the callback function.
618  *
619  * This function allows setting the callback function that is triggered once
620  * the cipher operation completes.
621  *
622  * The callback function is registered with the &ahash_request handle and
623  * must comply with the following template::
624  *
625  *	void callback_function(struct crypto_async_request *req, int error)
626  */
ahash_request_set_callback(struct ahash_request * req,u32 flags,crypto_completion_t compl,void * data)627 static inline void ahash_request_set_callback(struct ahash_request *req,
628 					      u32 flags,
629 					      crypto_completion_t compl,
630 					      void *data)
631 {
632 	req->base.complete = compl;
633 	req->base.data = data;
634 	req->base.flags = flags;
635 }
636 
637 /**
638  * ahash_request_set_crypt() - set data buffers
639  * @req: ahash_request handle to be updated
640  * @src: source scatter/gather list
641  * @result: buffer that is filled with the message digest -- the caller must
642  *	    ensure that the buffer has sufficient space by, for example, calling
643  *	    crypto_ahash_digestsize()
644  * @nbytes: number of bytes to process from the source scatter/gather list
645  *
646  * By using this call, the caller references the source scatter/gather list.
647  * The source scatter/gather list points to the data the message digest is to
648  * be calculated for.
649  */
ahash_request_set_crypt(struct ahash_request * req,struct scatterlist * src,u8 * result,unsigned int nbytes)650 static inline void ahash_request_set_crypt(struct ahash_request *req,
651 					   struct scatterlist *src, u8 *result,
652 					   unsigned int nbytes)
653 {
654 	req->src = src;
655 	req->nbytes = nbytes;
656 	req->result = result;
657 }
658 
659 /**
660  * DOC: Synchronous Message Digest API
661  *
662  * The synchronous message digest API is used with the ciphers of type
663  * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
664  *
665  * The message digest API is able to maintain state information for the
666  * caller.
667  *
668  * The synchronous message digest API can store user-related context in in its
669  * shash_desc request data structure.
670  */
671 
672 /**
673  * crypto_alloc_shash() - allocate message digest handle
674  * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
675  *	      message digest cipher
676  * @type: specifies the type of the cipher
677  * @mask: specifies the mask for the cipher
678  *
679  * Allocate a cipher handle for a message digest. The returned &struct
680  * crypto_shash is the cipher handle that is required for any subsequent
681  * API invocation for that message digest.
682  *
683  * Return: allocated cipher handle in case of success; IS_ERR() is true in case
684  *	   of an error, PTR_ERR() returns the error code.
685  */
686 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
687 					u32 mask);
688 
crypto_shash_tfm(struct crypto_shash * tfm)689 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
690 {
691 	return &tfm->base;
692 }
693 
694 /**
695  * crypto_free_shash() - zeroize and free the message digest handle
696  * @tfm: cipher handle to be freed
697  *
698  * If @tfm is a NULL or error pointer, this function does nothing.
699  */
crypto_free_shash(struct crypto_shash * tfm)700 static inline void crypto_free_shash(struct crypto_shash *tfm)
701 {
702 	crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
703 }
704 
crypto_shash_alg_name(struct crypto_shash * tfm)705 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
706 {
707 	return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
708 }
709 
crypto_shash_driver_name(struct crypto_shash * tfm)710 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
711 {
712 	return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
713 }
714 
crypto_shash_alignmask(struct crypto_shash * tfm)715 static inline unsigned int crypto_shash_alignmask(
716 	struct crypto_shash *tfm)
717 {
718 	return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
719 }
720 
721 /**
722  * crypto_shash_blocksize() - obtain block size for cipher
723  * @tfm: cipher handle
724  *
725  * The block size for the message digest cipher referenced with the cipher
726  * handle is returned.
727  *
728  * Return: block size of cipher
729  */
crypto_shash_blocksize(struct crypto_shash * tfm)730 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
731 {
732 	return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
733 }
734 
__crypto_shash_alg(struct crypto_alg * alg)735 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
736 {
737 	return container_of(alg, struct shash_alg, base);
738 }
739 
crypto_shash_alg(struct crypto_shash * tfm)740 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
741 {
742 	return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
743 }
744 
745 /**
746  * crypto_shash_digestsize() - obtain message digest size
747  * @tfm: cipher handle
748  *
749  * The size for the message digest created by the message digest cipher
750  * referenced with the cipher handle is returned.
751  *
752  * Return: digest size of cipher
753  */
crypto_shash_digestsize(struct crypto_shash * tfm)754 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
755 {
756 	return crypto_shash_alg(tfm)->digestsize;
757 }
758 
crypto_shash_statesize(struct crypto_shash * tfm)759 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
760 {
761 	return crypto_shash_alg(tfm)->statesize;
762 }
763 
crypto_shash_get_flags(struct crypto_shash * tfm)764 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
765 {
766 	return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
767 }
768 
crypto_shash_set_flags(struct crypto_shash * tfm,u32 flags)769 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
770 {
771 	crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
772 }
773 
crypto_shash_clear_flags(struct crypto_shash * tfm,u32 flags)774 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
775 {
776 	crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
777 }
778 
779 /**
780  * crypto_shash_descsize() - obtain the operational state size
781  * @tfm: cipher handle
782  *
783  * The size of the operational state the cipher needs during operation is
784  * returned for the hash referenced with the cipher handle. This size is
785  * required to calculate the memory requirements to allow the caller allocating
786  * sufficient memory for operational state.
787  *
788  * The operational state is defined with struct shash_desc where the size of
789  * that data structure is to be calculated as
790  * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
791  *
792  * Return: size of the operational state
793  */
crypto_shash_descsize(struct crypto_shash * tfm)794 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
795 {
796 	return tfm->descsize;
797 }
798 
shash_desc_ctx(struct shash_desc * desc)799 static inline void *shash_desc_ctx(struct shash_desc *desc)
800 {
801 	return desc->__ctx;
802 }
803 
804 /**
805  * crypto_shash_setkey() - set key for message digest
806  * @tfm: cipher handle
807  * @key: buffer holding the key
808  * @keylen: length of the key in bytes
809  *
810  * The caller provided key is set for the keyed message digest cipher. The
811  * cipher handle must point to a keyed message digest cipher in order for this
812  * function to succeed.
813  *
814  * Return: 0 if the setting of the key was successful; < 0 if an error occurred
815  */
816 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
817 			unsigned int keylen);
818 
819 /**
820  * crypto_shash_digest() - calculate message digest for buffer
821  * @desc: see crypto_shash_final()
822  * @data: see crypto_shash_update()
823  * @len: see crypto_shash_update()
824  * @out: see crypto_shash_final()
825  *
826  * This function is a "short-hand" for the function calls of crypto_shash_init,
827  * crypto_shash_update and crypto_shash_final. The parameters have the same
828  * meaning as discussed for those separate three functions.
829  *
830  * Return: 0 if the message digest creation was successful; < 0 if an error
831  *	   occurred
832  */
833 int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
834 			unsigned int len, u8 *out);
835 
836 /**
837  * crypto_shash_export() - extract operational state for message digest
838  * @desc: reference to the operational state handle whose state is exported
839  * @out: output buffer of sufficient size that can hold the hash state
840  *
841  * This function exports the hash state of the operational state handle into the
842  * caller-allocated output buffer out which must have sufficient size (e.g. by
843  * calling crypto_shash_descsize).
844  *
845  * Return: 0 if the export creation was successful; < 0 if an error occurred
846  */
crypto_shash_export(struct shash_desc * desc,void * out)847 static inline int crypto_shash_export(struct shash_desc *desc, void *out)
848 {
849 	return crypto_shash_alg(desc->tfm)->export(desc, out);
850 }
851 
852 /**
853  * crypto_shash_import() - import operational state
854  * @desc: reference to the operational state handle the state imported into
855  * @in: buffer holding the state
856  *
857  * This function imports the hash state into the operational state handle from
858  * the input buffer. That buffer should have been generated with the
859  * crypto_ahash_export function.
860  *
861  * Return: 0 if the import was successful; < 0 if an error occurred
862  */
crypto_shash_import(struct shash_desc * desc,const void * in)863 static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
864 {
865 	struct crypto_shash *tfm = desc->tfm;
866 
867 	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
868 		return -ENOKEY;
869 
870 	return crypto_shash_alg(tfm)->import(desc, in);
871 }
872 
873 /**
874  * crypto_shash_init() - (re)initialize message digest
875  * @desc: operational state handle that is already filled
876  *
877  * The call (re-)initializes the message digest referenced by the
878  * operational state handle. Any potentially existing state created by
879  * previous operations is discarded.
880  *
881  * Return: 0 if the message digest initialization was successful; < 0 if an
882  *	   error occurred
883  */
crypto_shash_init(struct shash_desc * desc)884 static inline int crypto_shash_init(struct shash_desc *desc)
885 {
886 	struct crypto_shash *tfm = desc->tfm;
887 
888 	if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
889 		return -ENOKEY;
890 
891 	return crypto_shash_alg(tfm)->init(desc);
892 }
893 
894 /**
895  * crypto_shash_update() - add data to message digest for processing
896  * @desc: operational state handle that is already initialized
897  * @data: input data to be added to the message digest
898  * @len: length of the input data
899  *
900  * Updates the message digest state of the operational state handle.
901  *
902  * Return: 0 if the message digest update was successful; < 0 if an error
903  *	   occurred
904  */
905 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
906 			unsigned int len);
907 
908 /**
909  * crypto_shash_final() - calculate message digest
910  * @desc: operational state handle that is already filled with data
911  * @out: output buffer filled with the message digest
912  *
913  * Finalize the message digest operation and create the message digest
914  * based on all data added to the cipher handle. The message digest is placed
915  * into the output buffer. The caller must ensure that the output buffer is
916  * large enough by using crypto_shash_digestsize.
917  *
918  * Return: 0 if the message digest creation was successful; < 0 if an error
919  *	   occurred
920  */
921 int crypto_shash_final(struct shash_desc *desc, u8 *out);
922 
923 /**
924  * crypto_shash_finup() - calculate message digest of buffer
925  * @desc: see crypto_shash_final()
926  * @data: see crypto_shash_update()
927  * @len: see crypto_shash_update()
928  * @out: see crypto_shash_final()
929  *
930  * This function is a "short-hand" for the function calls of
931  * crypto_shash_update and crypto_shash_final. The parameters have the same
932  * meaning as discussed for those separate functions.
933  *
934  * Return: 0 if the message digest creation was successful; < 0 if an error
935  *	   occurred
936  */
937 int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
938 		       unsigned int len, u8 *out);
939 
shash_desc_zero(struct shash_desc * desc)940 static inline void shash_desc_zero(struct shash_desc *desc)
941 {
942 	memzero_explicit(desc,
943 			 sizeof(*desc) + crypto_shash_descsize(desc->tfm));
944 }
945 
946 #endif	/* _CRYPTO_HASH_H */
947