1/* SPDX-License-Identifier: GPL-2.0-or-later */
  2/*
  3 * Symmetric key ciphers.
  4 * 
  5 * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au>
 
 
 
 
 
 
  6 */
  7
  8#ifndef _CRYPTO_SKCIPHER_H
  9#define _CRYPTO_SKCIPHER_H
 10
 11#include <linux/crypto.h>
 12#include <linux/kernel.h>
 13#include <linux/slab.h>
 14
 15/**
 16 *	struct skcipher_request - Symmetric key cipher request
 17 *	@cryptlen: Number of bytes to encrypt or decrypt
 18 *	@iv: Initialisation Vector
 19 *	@src: Source SG list
 20 *	@dst: Destination SG list
 21 *	@base: Underlying async request
 22 *	@__ctx: Start of private context data
 23 */
 24struct skcipher_request {
 25	unsigned int cryptlen;
 26
 27	u8 *iv;
 28
 29	struct scatterlist *src;
 30	struct scatterlist *dst;
 31
 32	struct crypto_async_request base;
 33
 34	void *__ctx[] CRYPTO_MINALIGN_ATTR;
 35};
 36
 
 
 
 
 
 
 
 
 
 
 
 
 
 37struct crypto_skcipher {
 
 
 
 
 
 
 38	unsigned int reqsize;
 
 39
 40	struct crypto_tfm base;
 41};
 42
 43struct crypto_sync_skcipher {
 44	struct crypto_skcipher base;
 45};
 46
 47/**
 48 * struct skcipher_alg - symmetric key cipher definition
 49 * @min_keysize: Minimum key size supported by the transformation. This is the
 50 *		 smallest key length supported by this transformation algorithm.
 51 *		 This must be set to one of the pre-defined values as this is
 52 *		 not hardware specific. Possible values for this field can be
 53 *		 found via git grep "_MIN_KEY_SIZE" include/crypto/
 54 * @max_keysize: Maximum key size supported by the transformation. This is the
 55 *		 largest key length supported by this transformation algorithm.
 56 *		 This must be set to one of the pre-defined values as this is
 57 *		 not hardware specific. Possible values for this field can be
 58 *		 found via git grep "_MAX_KEY_SIZE" include/crypto/
 59 * @setkey: Set key for the transformation. This function is used to either
 60 *	    program a supplied key into the hardware or store the key in the
 61 *	    transformation context for programming it later. Note that this
 62 *	    function does modify the transformation context. This function can
 63 *	    be called multiple times during the existence of the transformation
 64 *	    object, so one must make sure the key is properly reprogrammed into
 65 *	    the hardware. This function is also responsible for checking the key
 66 *	    length for validity. In case a software fallback was put in place in
 67 *	    the @cra_init call, this function might need to use the fallback if
 68 *	    the algorithm doesn't support all of the key sizes.
 69 * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt
 70 *	     the supplied scatterlist containing the blocks of data. The crypto
 71 *	     API consumer is responsible for aligning the entries of the
 72 *	     scatterlist properly and making sure the chunks are correctly
 73 *	     sized. In case a software fallback was put in place in the
 74 *	     @cra_init call, this function might need to use the fallback if
 75 *	     the algorithm doesn't support all of the key sizes. In case the
 76 *	     key was stored in transformation context, the key might need to be
 77 *	     re-programmed into the hardware in this function. This function
 78 *	     shall not modify the transformation context, as this function may
 79 *	     be called in parallel with the same transformation object.
 80 * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt
 81 *	     and the conditions are exactly the same.
 82 * @init: Initialize the cryptographic transformation object. This function
 83 *	  is used to initialize the cryptographic transformation object.
 84 *	  This function is called only once at the instantiation time, right
 85 *	  after the transformation context was allocated. In case the
 86 *	  cryptographic hardware has some special requirements which need to
 87 *	  be handled by software, this function shall check for the precise
 88 *	  requirement of the transformation and put any software fallbacks
 89 *	  in place.
 90 * @exit: Deinitialize the cryptographic transformation object. This is a
 91 *	  counterpart to @init, used to remove various changes set in
 92 *	  @init.
 93 * @ivsize: IV size applicable for transformation. The consumer must provide an
 94 *	    IV of exactly that size to perform the encrypt or decrypt operation.
 95 * @chunksize: Equal to the block size except for stream ciphers such as
 96 *	       CTR where it is set to the underlying block size.
 97 * @walksize: Equal to the chunk size except in cases where the algorithm is
 98 * 	      considerably more efficient if it can operate on multiple chunks
 99 * 	      in parallel. Should be a multiple of chunksize.
100 * @base: Definition of a generic crypto algorithm.
101 *
102 * All fields except @ivsize are mandatory and must be filled.
103 */
104struct skcipher_alg {
105	int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
106	              unsigned int keylen);
107	int (*encrypt)(struct skcipher_request *req);
108	int (*decrypt)(struct skcipher_request *req);
109	int (*init)(struct crypto_skcipher *tfm);
110	void (*exit)(struct crypto_skcipher *tfm);
111
112	unsigned int min_keysize;
113	unsigned int max_keysize;
114	unsigned int ivsize;
115	unsigned int chunksize;
116	unsigned int walksize;
117
118	struct crypto_alg base;
119};
120
121#define MAX_SYNC_SKCIPHER_REQSIZE      384
122/*
123 * This performs a type-check against the "tfm" argument to make sure
124 * all users have the correct skcipher tfm for doing on-stack requests.
125 */
126#define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \
127	char __##name##_desc[sizeof(struct skcipher_request) + \
128			     MAX_SYNC_SKCIPHER_REQSIZE + \
129			     (!(sizeof((struct crypto_sync_skcipher *)1 == \
130				       (typeof(tfm))1))) \
131			    ] CRYPTO_MINALIGN_ATTR; \
132	struct skcipher_request *name = (void *)__##name##_desc
133
134/**
135 * DOC: Symmetric Key Cipher API
136 *
137 * Symmetric key cipher API is used with the ciphers of type
138 * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto).
139 *
140 * Asynchronous cipher operations imply that the function invocation for a
141 * cipher request returns immediately before the completion of the operation.
142 * The cipher request is scheduled as a separate kernel thread and therefore
143 * load-balanced on the different CPUs via the process scheduler. To allow
144 * the kernel crypto API to inform the caller about the completion of a cipher
145 * request, the caller must provide a callback function. That function is
146 * invoked with the cipher handle when the request completes.
147 *
148 * To support the asynchronous operation, additional information than just the
149 * cipher handle must be supplied to the kernel crypto API. That additional
150 * information is given by filling in the skcipher_request data structure.
151 *
152 * For the symmetric key cipher API, the state is maintained with the tfm
153 * cipher handle. A single tfm can be used across multiple calls and in
154 * parallel. For asynchronous block cipher calls, context data supplied and
155 * only used by the caller can be referenced the request data structure in
156 * addition to the IV used for the cipher request. The maintenance of such
157 * state information would be important for a crypto driver implementer to
158 * have, because when calling the callback function upon completion of the
159 * cipher operation, that callback function may need some information about
160 * which operation just finished if it invoked multiple in parallel. This
161 * state information is unused by the kernel crypto API.
162 */
163
164static inline struct crypto_skcipher *__crypto_skcipher_cast(
165	struct crypto_tfm *tfm)
166{
167	return container_of(tfm, struct crypto_skcipher, base);
168}
169
170/**
171 * crypto_alloc_skcipher() - allocate symmetric key cipher handle
172 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
173 *	      skcipher cipher
174 * @type: specifies the type of the cipher
175 * @mask: specifies the mask for the cipher
176 *
177 * Allocate a cipher handle for an skcipher. The returned struct
178 * crypto_skcipher is the cipher handle that is required for any subsequent
179 * API invocation for that skcipher.
180 *
181 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
182 *	   of an error, PTR_ERR() returns the error code.
183 */
184struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
185					      u32 type, u32 mask);
186
187struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name,
188					      u32 type, u32 mask);
189
190static inline struct crypto_tfm *crypto_skcipher_tfm(
191	struct crypto_skcipher *tfm)
192{
193	return &tfm->base;
194}
195
196/**
197 * crypto_free_skcipher() - zeroize and free cipher handle
198 * @tfm: cipher handle to be freed
199 *
200 * If @tfm is a NULL or error pointer, this function does nothing.
201 */
202static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
203{
204	crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
205}
206
207static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm)
 
 
 
 
 
 
 
 
 
 
 
208{
209	crypto_free_skcipher(&tfm->base);
 
210}
211
212/**
213 * crypto_has_skcipher() - Search for the availability of an skcipher.
214 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
215 *	      skcipher
216 * @type: specifies the type of the skcipher
217 * @mask: specifies the mask for the skcipher
218 *
219 * Return: true when the skcipher is known to the kernel crypto API; false
220 *	   otherwise
221 */
222int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask);
223
224static inline const char *crypto_skcipher_driver_name(
225	struct crypto_skcipher *tfm)
226{
227	return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm));
228}
229
230static inline struct skcipher_alg *crypto_skcipher_alg(
231	struct crypto_skcipher *tfm)
232{
233	return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
234			    struct skcipher_alg, base);
235}
236
237static inline unsigned int crypto_skcipher_alg_ivsize(struct skcipher_alg *alg)
238{
 
 
 
 
 
 
 
239	return alg->ivsize;
240}
241
242/**
243 * crypto_skcipher_ivsize() - obtain IV size
244 * @tfm: cipher handle
245 *
246 * The size of the IV for the skcipher referenced by the cipher handle is
247 * returned. This IV size may be zero if the cipher does not need an IV.
248 *
249 * Return: IV size in bytes
250 */
251static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
252{
253	return crypto_skcipher_alg(tfm)->ivsize;
254}
255
256static inline unsigned int crypto_sync_skcipher_ivsize(
257	struct crypto_sync_skcipher *tfm)
258{
259	return crypto_skcipher_ivsize(&tfm->base);
260}
 
261
262/**
263 * crypto_skcipher_blocksize() - obtain block size of cipher
264 * @tfm: cipher handle
265 *
266 * The block size for the skcipher referenced with the cipher handle is
267 * returned. The caller may use that information to allocate appropriate
268 * memory for the data returned by the encryption or decryption operation
269 *
270 * Return: block size of cipher
271 */
272static inline unsigned int crypto_skcipher_blocksize(
273	struct crypto_skcipher *tfm)
274{
275	return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
276}
277
278static inline unsigned int crypto_skcipher_alg_chunksize(
279	struct skcipher_alg *alg)
280{
281	return alg->chunksize;
 
 
 
 
 
 
 
282}
283
284/**
285 * crypto_skcipher_chunksize() - obtain chunk size
286 * @tfm: cipher handle
287 *
288 * The block size is set to one for ciphers such as CTR.  However,
289 * you still need to provide incremental updates in multiples of
290 * the underlying block size as the IV does not have sub-block
291 * granularity.  This is known in this API as the chunk size.
292 *
293 * Return: chunk size in bytes
294 */
295static inline unsigned int crypto_skcipher_chunksize(
296	struct crypto_skcipher *tfm)
297{
298	return crypto_skcipher_alg_chunksize(crypto_skcipher_alg(tfm));
299}
300
301static inline unsigned int crypto_sync_skcipher_blocksize(
302	struct crypto_sync_skcipher *tfm)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
303{
304	return crypto_skcipher_blocksize(&tfm->base);
305}
306
307static inline unsigned int crypto_skcipher_alignmask(
308	struct crypto_skcipher *tfm)
309{
310	return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
311}
312
313static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
314{
315	return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
316}
317
318static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm,
319					       u32 flags)
320{
321	crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags);
322}
323
324static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
325						 u32 flags)
326{
327	crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
328}
329
330static inline u32 crypto_sync_skcipher_get_flags(
331	struct crypto_sync_skcipher *tfm)
332{
333	return crypto_skcipher_get_flags(&tfm->base);
334}
335
336static inline void crypto_sync_skcipher_set_flags(
337	struct crypto_sync_skcipher *tfm, u32 flags)
338{
339	crypto_skcipher_set_flags(&tfm->base, flags);
340}
341
342static inline void crypto_sync_skcipher_clear_flags(
343	struct crypto_sync_skcipher *tfm, u32 flags)
344{
345	crypto_skcipher_clear_flags(&tfm->base, flags);
346}
347
348/**
349 * crypto_skcipher_setkey() - set key for cipher
350 * @tfm: cipher handle
351 * @key: buffer holding the key
352 * @keylen: length of the key in bytes
353 *
354 * The caller provided key is set for the skcipher referenced by the cipher
355 * handle.
356 *
357 * Note, the key length determines the cipher type. Many block ciphers implement
358 * different cipher modes depending on the key size, such as AES-128 vs AES-192
359 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
360 * is performed.
361 *
362 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
363 */
364int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
365			   const u8 *key, unsigned int keylen);
366
367static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm,
368					 const u8 *key, unsigned int keylen)
369{
370	return crypto_skcipher_setkey(&tfm->base, key, keylen);
371}
372
373static inline unsigned int crypto_skcipher_min_keysize(
374	struct crypto_skcipher *tfm)
375{
376	return crypto_skcipher_alg(tfm)->min_keysize;
377}
378
379static inline unsigned int crypto_skcipher_max_keysize(
380	struct crypto_skcipher *tfm)
381{
382	return crypto_skcipher_alg(tfm)->max_keysize;
383}
384
385/**
386 * crypto_skcipher_reqtfm() - obtain cipher handle from request
387 * @req: skcipher_request out of which the cipher handle is to be obtained
388 *
389 * Return the crypto_skcipher handle when furnishing an skcipher_request
390 * data structure.
391 *
392 * Return: crypto_skcipher handle
393 */
394static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
395	struct skcipher_request *req)
396{
397	return __crypto_skcipher_cast(req->base.tfm);
398}
399
400static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm(
401	struct skcipher_request *req)
402{
403	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
404
405	return container_of(tfm, struct crypto_sync_skcipher, base);
406}
407
408/**
409 * crypto_skcipher_encrypt() - encrypt plaintext
410 * @req: reference to the skcipher_request handle that holds all information
411 *	 needed to perform the cipher operation
412 *
413 * Encrypt plaintext data using the skcipher_request handle. That data
414 * structure and how it is filled with data is discussed with the
415 * skcipher_request_* functions.
416 *
417 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
418 */
419int crypto_skcipher_encrypt(struct skcipher_request *req);
 
 
 
 
 
 
 
 
420
421/**
422 * crypto_skcipher_decrypt() - decrypt ciphertext
423 * @req: reference to the skcipher_request handle that holds all information
424 *	 needed to perform the cipher operation
425 *
426 * Decrypt ciphertext data using the skcipher_request handle. That data
427 * structure and how it is filled with data is discussed with the
428 * skcipher_request_* functions.
429 *
430 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
431 */
432int crypto_skcipher_decrypt(struct skcipher_request *req);
 
 
 
 
 
 
 
 
433
434/**
435 * DOC: Symmetric Key Cipher Request Handle
436 *
437 * The skcipher_request data structure contains all pointers to data
438 * required for the symmetric key cipher operation. This includes the cipher
439 * handle (which can be used by multiple skcipher_request instances), pointer
440 * to plaintext and ciphertext, asynchronous callback function, etc. It acts
441 * as a handle to the skcipher_request_* API calls in a similar way as
442 * skcipher handle to the crypto_skcipher_* API calls.
443 */
444
445/**
446 * crypto_skcipher_reqsize() - obtain size of the request data structure
447 * @tfm: cipher handle
448 *
449 * Return: number of bytes
450 */
451static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm)
452{
453	return tfm->reqsize;
454}
455
456/**
457 * skcipher_request_set_tfm() - update cipher handle reference in request
458 * @req: request handle to be modified
459 * @tfm: cipher handle that shall be added to the request handle
460 *
461 * Allow the caller to replace the existing skcipher handle in the request
462 * data structure with a different one.
463 */
464static inline void skcipher_request_set_tfm(struct skcipher_request *req,
465					    struct crypto_skcipher *tfm)
466{
467	req->base.tfm = crypto_skcipher_tfm(tfm);
468}
469
470static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req,
471					    struct crypto_sync_skcipher *tfm)
472{
473	skcipher_request_set_tfm(req, &tfm->base);
474}
475
476static inline struct skcipher_request *skcipher_request_cast(
477	struct crypto_async_request *req)
478{
479	return container_of(req, struct skcipher_request, base);
480}
481
482/**
483 * skcipher_request_alloc() - allocate request data structure
484 * @tfm: cipher handle to be registered with the request
485 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
486 *
487 * Allocate the request data structure that must be used with the skcipher
488 * encrypt and decrypt API calls. During the allocation, the provided skcipher
489 * handle is registered in the request data structure.
490 *
491 * Return: allocated request handle in case of success, or NULL if out of memory
492 */
493static inline struct skcipher_request *skcipher_request_alloc(
494	struct crypto_skcipher *tfm, gfp_t gfp)
495{
496	struct skcipher_request *req;
497
498	req = kmalloc(sizeof(struct skcipher_request) +
499		      crypto_skcipher_reqsize(tfm), gfp);
500
501	if (likely(req))
502		skcipher_request_set_tfm(req, tfm);
503
504	return req;
505}
506
507/**
508 * skcipher_request_free() - zeroize and free request data structure
509 * @req: request data structure cipher handle to be freed
510 */
511static inline void skcipher_request_free(struct skcipher_request *req)
512{
513	kfree_sensitive(req);
514}
515
516static inline void skcipher_request_zero(struct skcipher_request *req)
517{
518	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
519
520	memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm));
521}
522
523/**
524 * skcipher_request_set_callback() - set asynchronous callback function
525 * @req: request handle
526 * @flags: specify zero or an ORing of the flags
527 *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
528 *	   increase the wait queue beyond the initial maximum size;
529 *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
530 * @compl: callback function pointer to be registered with the request handle
531 * @data: The data pointer refers to memory that is not used by the kernel
532 *	  crypto API, but provided to the callback function for it to use. Here,
533 *	  the caller can provide a reference to memory the callback function can
534 *	  operate on. As the callback function is invoked asynchronously to the
535 *	  related functionality, it may need to access data structures of the
536 *	  related functionality which can be referenced using this pointer. The
537 *	  callback function can access the memory via the "data" field in the
538 *	  crypto_async_request data structure provided to the callback function.
539 *
540 * This function allows setting the callback function that is triggered once the
541 * cipher operation completes.
542 *
543 * The callback function is registered with the skcipher_request handle and
544 * must comply with the following template::
545 *
546 *	void callback_function(struct crypto_async_request *req, int error)
547 */
548static inline void skcipher_request_set_callback(struct skcipher_request *req,
549						 u32 flags,
550						 crypto_completion_t compl,
551						 void *data)
552{
553	req->base.complete = compl;
554	req->base.data = data;
555	req->base.flags = flags;
556}
557
558/**
559 * skcipher_request_set_crypt() - set data buffers
560 * @req: request handle
561 * @src: source scatter / gather list
562 * @dst: destination scatter / gather list
563 * @cryptlen: number of bytes to process from @src
564 * @iv: IV for the cipher operation which must comply with the IV size defined
565 *      by crypto_skcipher_ivsize
566 *
567 * This function allows setting of the source data and destination data
568 * scatter / gather lists.
569 *
570 * For encryption, the source is treated as the plaintext and the
571 * destination is the ciphertext. For a decryption operation, the use is
572 * reversed - the source is the ciphertext and the destination is the plaintext.
573 */
574static inline void skcipher_request_set_crypt(
575	struct skcipher_request *req,
576	struct scatterlist *src, struct scatterlist *dst,
577	unsigned int cryptlen, void *iv)
578{
579	req->src = src;
580	req->dst = dst;
581	req->cryptlen = cryptlen;
582	req->iv = iv;
583}
584
585#endif	/* _CRYPTO_SKCIPHER_H */
586

 
  1/*
  2 * Symmetric key ciphers.
  3 * 
  4 * Copyright (c) 2007-2015 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_SKCIPHER_H
 14#define _CRYPTO_SKCIPHER_H
 15
 16#include <linux/crypto.h>
 17#include <linux/kernel.h>
 18#include <linux/slab.h>
 19
 20/**
 21 *	struct skcipher_request - Symmetric key cipher request
 22 *	@cryptlen: Number of bytes to encrypt or decrypt
 23 *	@iv: Initialisation Vector
 24 *	@src: Source SG list
 25 *	@dst: Destination SG list
 26 *	@base: Underlying async request request
 27 *	@__ctx: Start of private context data
 28 */
 29struct skcipher_request {
 30	unsigned int cryptlen;
 31
 32	u8 *iv;
 33
 34	struct scatterlist *src;
 35	struct scatterlist *dst;
 36
 37	struct crypto_async_request base;
 38
 39	void *__ctx[] CRYPTO_MINALIGN_ATTR;
 40};
 41
 42/**
 43 *	struct skcipher_givcrypt_request - Crypto request with IV generation
 44 *	@seq: Sequence number for IV generation
 45 *	@giv: Space for generated IV
 46 *	@creq: The crypto request itself
 47 */
 48struct skcipher_givcrypt_request {
 49	u64 seq;
 50	u8 *giv;
 51
 52	struct ablkcipher_request creq;
 53};
 54
 55struct crypto_skcipher {
 56	int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
 57	              unsigned int keylen);
 58	int (*encrypt)(struct skcipher_request *req);
 59	int (*decrypt)(struct skcipher_request *req);
 60
 61	unsigned int ivsize;
 62	unsigned int reqsize;
 63	unsigned int keysize;
 64
 65	struct crypto_tfm base;
 66};
 67
 
 
 
 
 68/**
 69 * struct skcipher_alg - symmetric key cipher definition
 70 * @min_keysize: Minimum key size supported by the transformation. This is the
 71 *		 smallest key length supported by this transformation algorithm.
 72 *		 This must be set to one of the pre-defined values as this is
 73 *		 not hardware specific. Possible values for this field can be
 74 *		 found via git grep "_MIN_KEY_SIZE" include/crypto/
 75 * @max_keysize: Maximum key size supported by the transformation. This is the
 76 *		 largest key length supported by this transformation algorithm.
 77 *		 This must be set to one of the pre-defined values as this is
 78 *		 not hardware specific. Possible values for this field can be
 79 *		 found via git grep "_MAX_KEY_SIZE" include/crypto/
 80 * @setkey: Set key for the transformation. This function is used to either
 81 *	    program a supplied key into the hardware or store the key in the
 82 *	    transformation context for programming it later. Note that this
 83 *	    function does modify the transformation context. This function can
 84 *	    be called multiple times during the existence of the transformation
 85 *	    object, so one must make sure the key is properly reprogrammed into
 86 *	    the hardware. This function is also responsible for checking the key
 87 *	    length for validity. In case a software fallback was put in place in
 88 *	    the @cra_init call, this function might need to use the fallback if
 89 *	    the algorithm doesn't support all of the key sizes.
 90 * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt
 91 *	     the supplied scatterlist containing the blocks of data. The crypto
 92 *	     API consumer is responsible for aligning the entries of the
 93 *	     scatterlist properly and making sure the chunks are correctly
 94 *	     sized. In case a software fallback was put in place in the
 95 *	     @cra_init call, this function might need to use the fallback if
 96 *	     the algorithm doesn't support all of the key sizes. In case the
 97 *	     key was stored in transformation context, the key might need to be
 98 *	     re-programmed into the hardware in this function. This function
 99 *	     shall not modify the transformation context, as this function may
100 *	     be called in parallel with the same transformation object.
101 * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt
102 *	     and the conditions are exactly the same.
103 * @init: Initialize the cryptographic transformation object. This function
104 *	  is used to initialize the cryptographic transformation object.
105 *	  This function is called only once at the instantiation time, right
106 *	  after the transformation context was allocated. In case the
107 *	  cryptographic hardware has some special requirements which need to
108 *	  be handled by software, this function shall check for the precise
109 *	  requirement of the transformation and put any software fallbacks
110 *	  in place.
111 * @exit: Deinitialize the cryptographic transformation object. This is a
112 *	  counterpart to @init, used to remove various changes set in
113 *	  @init.
114 * @ivsize: IV size applicable for transformation. The consumer must provide an
115 *	    IV of exactly that size to perform the encrypt or decrypt operation.
116 * @chunksize: Equal to the block size except for stream ciphers such as
117 *	       CTR where it is set to the underlying block size.
118 * @walksize: Equal to the chunk size except in cases where the algorithm is
119 * 	      considerably more efficient if it can operate on multiple chunks
120 * 	      in parallel. Should be a multiple of chunksize.
121 * @base: Definition of a generic crypto algorithm.
122 *
123 * All fields except @ivsize are mandatory and must be filled.
124 */
125struct skcipher_alg {
126	int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
127	              unsigned int keylen);
128	int (*encrypt)(struct skcipher_request *req);
129	int (*decrypt)(struct skcipher_request *req);
130	int (*init)(struct crypto_skcipher *tfm);
131	void (*exit)(struct crypto_skcipher *tfm);
132
133	unsigned int min_keysize;
134	unsigned int max_keysize;
135	unsigned int ivsize;
136	unsigned int chunksize;
137	unsigned int walksize;
138
139	struct crypto_alg base;
140};
141
142#define SKCIPHER_REQUEST_ON_STACK(name, tfm) \
 
 
 
 
 
143	char __##name##_desc[sizeof(struct skcipher_request) + \
144		crypto_skcipher_reqsize(tfm)] CRYPTO_MINALIGN_ATTR; \
 
 
 
145	struct skcipher_request *name = (void *)__##name##_desc
146
147/**
148 * DOC: Symmetric Key Cipher API
149 *
150 * Symmetric key cipher API is used with the ciphers of type
151 * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto).
152 *
153 * Asynchronous cipher operations imply that the function invocation for a
154 * cipher request returns immediately before the completion of the operation.
155 * The cipher request is scheduled as a separate kernel thread and therefore
156 * load-balanced on the different CPUs via the process scheduler. To allow
157 * the kernel crypto API to inform the caller about the completion of a cipher
158 * request, the caller must provide a callback function. That function is
159 * invoked with the cipher handle when the request completes.
160 *
161 * To support the asynchronous operation, additional information than just the
162 * cipher handle must be supplied to the kernel crypto API. That additional
163 * information is given by filling in the skcipher_request data structure.
164 *
165 * For the symmetric key cipher API, the state is maintained with the tfm
166 * cipher handle. A single tfm can be used across multiple calls and in
167 * parallel. For asynchronous block cipher calls, context data supplied and
168 * only used by the caller can be referenced the request data structure in
169 * addition to the IV used for the cipher request. The maintenance of such
170 * state information would be important for a crypto driver implementer to
171 * have, because when calling the callback function upon completion of the
172 * cipher operation, that callback function may need some information about
173 * which operation just finished if it invoked multiple in parallel. This
174 * state information is unused by the kernel crypto API.
175 */
176
177static inline struct crypto_skcipher *__crypto_skcipher_cast(
178	struct crypto_tfm *tfm)
179{
180	return container_of(tfm, struct crypto_skcipher, base);
181}
182
183/**
184 * crypto_alloc_skcipher() - allocate symmetric key cipher handle
185 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
186 *	      skcipher cipher
187 * @type: specifies the type of the cipher
188 * @mask: specifies the mask for the cipher
189 *
190 * Allocate a cipher handle for an skcipher. The returned struct
191 * crypto_skcipher is the cipher handle that is required for any subsequent
192 * API invocation for that skcipher.
193 *
194 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
195 *	   of an error, PTR_ERR() returns the error code.
196 */
197struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
198					      u32 type, u32 mask);
199
 
 
 
200static inline struct crypto_tfm *crypto_skcipher_tfm(
201	struct crypto_skcipher *tfm)
202{
203	return &tfm->base;
204}
205
206/**
207 * crypto_free_skcipher() - zeroize and free cipher handle
208 * @tfm: cipher handle to be freed
 
 
209 */
210static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
211{
212	crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
213}
214
215/**
216 * crypto_has_skcipher() - Search for the availability of an skcipher.
217 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
218 *	      skcipher
219 * @type: specifies the type of the cipher
220 * @mask: specifies the mask for the cipher
221 *
222 * Return: true when the skcipher is known to the kernel crypto API; false
223 *	   otherwise
224 */
225static inline int crypto_has_skcipher(const char *alg_name, u32 type,
226					u32 mask)
227{
228	return crypto_has_alg(alg_name, crypto_skcipher_type(type),
229			      crypto_skcipher_mask(mask));
230}
231
232/**
233 * crypto_has_skcipher2() - Search for the availability of an skcipher.
234 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
235 *	      skcipher
236 * @type: specifies the type of the skcipher
237 * @mask: specifies the mask for the skcipher
238 *
239 * Return: true when the skcipher is known to the kernel crypto API; false
240 *	   otherwise
241 */
242int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask);
243
244static inline const char *crypto_skcipher_driver_name(
245	struct crypto_skcipher *tfm)
246{
247	return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm));
248}
249
250static inline struct skcipher_alg *crypto_skcipher_alg(
251	struct crypto_skcipher *tfm)
252{
253	return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
254			    struct skcipher_alg, base);
255}
256
257static inline unsigned int crypto_skcipher_alg_ivsize(struct skcipher_alg *alg)
258{
259	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
260	    CRYPTO_ALG_TYPE_BLKCIPHER)
261		return alg->base.cra_blkcipher.ivsize;
262
263	if (alg->base.cra_ablkcipher.encrypt)
264		return alg->base.cra_ablkcipher.ivsize;
265
266	return alg->ivsize;
267}
268
269/**
270 * crypto_skcipher_ivsize() - obtain IV size
271 * @tfm: cipher handle
272 *
273 * The size of the IV for the skcipher referenced by the cipher handle is
274 * returned. This IV size may be zero if the cipher does not need an IV.
275 *
276 * Return: IV size in bytes
277 */
278static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
279{
280	return tfm->ivsize;
281}
282
283static inline unsigned int crypto_skcipher_alg_chunksize(
284	struct skcipher_alg *alg)
285{
286	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
287	    CRYPTO_ALG_TYPE_BLKCIPHER)
288		return alg->base.cra_blocksize;
289
290	if (alg->base.cra_ablkcipher.encrypt)
291		return alg->base.cra_blocksize;
292
293	return alg->chunksize;
 
 
 
 
 
 
 
 
 
 
294}
295
296static inline unsigned int crypto_skcipher_alg_walksize(
297	struct skcipher_alg *alg)
298{
299	if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
300	    CRYPTO_ALG_TYPE_BLKCIPHER)
301		return alg->base.cra_blocksize;
302
303	if (alg->base.cra_ablkcipher.encrypt)
304		return alg->base.cra_blocksize;
305
306	return alg->walksize;
307}
308
309/**
310 * crypto_skcipher_chunksize() - obtain chunk size
311 * @tfm: cipher handle
312 *
313 * The block size is set to one for ciphers such as CTR.  However,
314 * you still need to provide incremental updates in multiples of
315 * the underlying block size as the IV does not have sub-block
316 * granularity.  This is known in this API as the chunk size.
317 *
318 * Return: chunk size in bytes
319 */
320static inline unsigned int crypto_skcipher_chunksize(
321	struct crypto_skcipher *tfm)
322{
323	return crypto_skcipher_alg_chunksize(crypto_skcipher_alg(tfm));
324}
325
326/**
327 * crypto_skcipher_walksize() - obtain walk size
328 * @tfm: cipher handle
329 *
330 * In some cases, algorithms can only perform optimally when operating on
331 * multiple blocks in parallel. This is reflected by the walksize, which
332 * must be a multiple of the chunksize (or equal if the concern does not
333 * apply)
334 *
335 * Return: walk size in bytes
336 */
337static inline unsigned int crypto_skcipher_walksize(
338	struct crypto_skcipher *tfm)
339{
340	return crypto_skcipher_alg_walksize(crypto_skcipher_alg(tfm));
341}
342
343/**
344 * crypto_skcipher_blocksize() - obtain block size of cipher
345 * @tfm: cipher handle
346 *
347 * The block size for the skcipher referenced with the cipher handle is
348 * returned. The caller may use that information to allocate appropriate
349 * memory for the data returned by the encryption or decryption operation
350 *
351 * Return: block size of cipher
352 */
353static inline unsigned int crypto_skcipher_blocksize(
354	struct crypto_skcipher *tfm)
355{
356	return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
357}
358
359static inline unsigned int crypto_skcipher_alignmask(
360	struct crypto_skcipher *tfm)
361{
362	return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
363}
364
365static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
366{
367	return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
368}
369
370static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm,
371					       u32 flags)
372{
373	crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags);
374}
375
376static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
377						 u32 flags)
378{
379	crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
380}
381
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
382/**
383 * crypto_skcipher_setkey() - set key for cipher
384 * @tfm: cipher handle
385 * @key: buffer holding the key
386 * @keylen: length of the key in bytes
387 *
388 * The caller provided key is set for the skcipher referenced by the cipher
389 * handle.
390 *
391 * Note, the key length determines the cipher type. Many block ciphers implement
392 * different cipher modes depending on the key size, such as AES-128 vs AES-192
393 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
394 * is performed.
395 *
396 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
397 */
398static inline int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
 
 
 
399					 const u8 *key, unsigned int keylen)
400{
401	return tfm->setkey(tfm, key, keylen);
 
 
 
 
 
 
402}
403
404static inline unsigned int crypto_skcipher_default_keysize(
405	struct crypto_skcipher *tfm)
406{
407	return tfm->keysize;
408}
409
410/**
411 * crypto_skcipher_reqtfm() - obtain cipher handle from request
412 * @req: skcipher_request out of which the cipher handle is to be obtained
413 *
414 * Return the crypto_skcipher handle when furnishing an skcipher_request
415 * data structure.
416 *
417 * Return: crypto_skcipher handle
418 */
419static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
420	struct skcipher_request *req)
421{
422	return __crypto_skcipher_cast(req->base.tfm);
423}
424
 
 
 
 
 
 
 
 
425/**
426 * crypto_skcipher_encrypt() - encrypt plaintext
427 * @req: reference to the skcipher_request handle that holds all information
428 *	 needed to perform the cipher operation
429 *
430 * Encrypt plaintext data using the skcipher_request handle. That data
431 * structure and how it is filled with data is discussed with the
432 * skcipher_request_* functions.
433 *
434 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
435 */
436static inline int crypto_skcipher_encrypt(struct skcipher_request *req)
437{
438	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
439
440	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
441		return -ENOKEY;
442
443	return tfm->encrypt(req);
444}
445
446/**
447 * crypto_skcipher_decrypt() - decrypt ciphertext
448 * @req: reference to the skcipher_request handle that holds all information
449 *	 needed to perform the cipher operation
450 *
451 * Decrypt ciphertext data using the skcipher_request handle. That data
452 * structure and how it is filled with data is discussed with the
453 * skcipher_request_* functions.
454 *
455 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
456 */
457static inline int crypto_skcipher_decrypt(struct skcipher_request *req)
458{
459	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
460
461	if (crypto_skcipher_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
462		return -ENOKEY;
463
464	return tfm->decrypt(req);
465}
466
467/**
468 * DOC: Symmetric Key Cipher Request Handle
469 *
470 * The skcipher_request data structure contains all pointers to data
471 * required for the symmetric key cipher operation. This includes the cipher
472 * handle (which can be used by multiple skcipher_request instances), pointer
473 * to plaintext and ciphertext, asynchronous callback function, etc. It acts
474 * as a handle to the skcipher_request_* API calls in a similar way as
475 * skcipher handle to the crypto_skcipher_* API calls.
476 */
477
478/**
479 * crypto_skcipher_reqsize() - obtain size of the request data structure
480 * @tfm: cipher handle
481 *
482 * Return: number of bytes
483 */
484static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm)
485{
486	return tfm->reqsize;
487}
488
489/**
490 * skcipher_request_set_tfm() - update cipher handle reference in request
491 * @req: request handle to be modified
492 * @tfm: cipher handle that shall be added to the request handle
493 *
494 * Allow the caller to replace the existing skcipher handle in the request
495 * data structure with a different one.
496 */
497static inline void skcipher_request_set_tfm(struct skcipher_request *req,
498					    struct crypto_skcipher *tfm)
499{
500	req->base.tfm = crypto_skcipher_tfm(tfm);
501}
502
 
 
 
 
 
 
503static inline struct skcipher_request *skcipher_request_cast(
504	struct crypto_async_request *req)
505{
506	return container_of(req, struct skcipher_request, base);
507}
508
509/**
510 * skcipher_request_alloc() - allocate request data structure
511 * @tfm: cipher handle to be registered with the request
512 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
513 *
514 * Allocate the request data structure that must be used with the skcipher
515 * encrypt and decrypt API calls. During the allocation, the provided skcipher
516 * handle is registered in the request data structure.
517 *
518 * Return: allocated request handle in case of success, or NULL if out of memory
519 */
520static inline struct skcipher_request *skcipher_request_alloc(
521	struct crypto_skcipher *tfm, gfp_t gfp)
522{
523	struct skcipher_request *req;
524
525	req = kmalloc(sizeof(struct skcipher_request) +
526		      crypto_skcipher_reqsize(tfm), gfp);
527
528	if (likely(req))
529		skcipher_request_set_tfm(req, tfm);
530
531	return req;
532}
533
534/**
535 * skcipher_request_free() - zeroize and free request data structure
536 * @req: request data structure cipher handle to be freed
537 */
538static inline void skcipher_request_free(struct skcipher_request *req)
539{
540	kzfree(req);
541}
542
543static inline void skcipher_request_zero(struct skcipher_request *req)
544{
545	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
546
547	memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm));
548}
549
550/**
551 * skcipher_request_set_callback() - set asynchronous callback function
552 * @req: request handle
553 * @flags: specify zero or an ORing of the flags
554 *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
555 *	   increase the wait queue beyond the initial maximum size;
556 *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
557 * @compl: callback function pointer to be registered with the request handle
558 * @data: The data pointer refers to memory that is not used by the kernel
559 *	  crypto API, but provided to the callback function for it to use. Here,
560 *	  the caller can provide a reference to memory the callback function can
561 *	  operate on. As the callback function is invoked asynchronously to the
562 *	  related functionality, it may need to access data structures of the
563 *	  related functionality which can be referenced using this pointer. The
564 *	  callback function can access the memory via the "data" field in the
565 *	  crypto_async_request data structure provided to the callback function.
566 *
567 * This function allows setting the callback function that is triggered once the
568 * cipher operation completes.
569 *
570 * The callback function is registered with the skcipher_request handle and
571 * must comply with the following template::
572 *
573 *	void callback_function(struct crypto_async_request *req, int error)
574 */
575static inline void skcipher_request_set_callback(struct skcipher_request *req,
576						 u32 flags,
577						 crypto_completion_t compl,
578						 void *data)
579{
580	req->base.complete = compl;
581	req->base.data = data;
582	req->base.flags = flags;
583}
584
585/**
586 * skcipher_request_set_crypt() - set data buffers
587 * @req: request handle
588 * @src: source scatter / gather list
589 * @dst: destination scatter / gather list
590 * @cryptlen: number of bytes to process from @src
591 * @iv: IV for the cipher operation which must comply with the IV size defined
592 *      by crypto_skcipher_ivsize
593 *
594 * This function allows setting of the source data and destination data
595 * scatter / gather lists.
596 *
597 * For encryption, the source is treated as the plaintext and the
598 * destination is the ciphertext. For a decryption operation, the use is
599 * reversed - the source is the ciphertext and the destination is the plaintext.
600 */
601static inline void skcipher_request_set_crypt(
602	struct skcipher_request *req,
603	struct scatterlist *src, struct scatterlist *dst,
604	unsigned int cryptlen, void *iv)
605{
606	req->src = src;
607	req->dst = dst;
608	req->cryptlen = cryptlen;
609	req->iv = iv;
610}
611
612#endif	/* _CRYPTO_SKCIPHER_H */
613