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1/*
2 * Symmetric key ciphers.
3 *
4 * Copyright (c) 2007 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_givcrypt_request - Crypto request with IV generation
22 * @seq: Sequence number for IV generation
23 * @giv: Space for generated IV
24 * @creq: The crypto request itself
25 */
26struct skcipher_givcrypt_request {
27 u64 seq;
28 u8 *giv;
29
30 struct ablkcipher_request creq;
31};
32
33static inline struct crypto_ablkcipher *skcipher_givcrypt_reqtfm(
34 struct skcipher_givcrypt_request *req)
35{
36 return crypto_ablkcipher_reqtfm(&req->creq);
37}
38
39static inline int crypto_skcipher_givencrypt(
40 struct skcipher_givcrypt_request *req)
41{
42 struct ablkcipher_tfm *crt =
43 crypto_ablkcipher_crt(skcipher_givcrypt_reqtfm(req));
44 return crt->givencrypt(req);
45};
46
47static inline int crypto_skcipher_givdecrypt(
48 struct skcipher_givcrypt_request *req)
49{
50 struct ablkcipher_tfm *crt =
51 crypto_ablkcipher_crt(skcipher_givcrypt_reqtfm(req));
52 return crt->givdecrypt(req);
53};
54
55static inline void skcipher_givcrypt_set_tfm(
56 struct skcipher_givcrypt_request *req, struct crypto_ablkcipher *tfm)
57{
58 req->creq.base.tfm = crypto_ablkcipher_tfm(tfm);
59}
60
61static inline struct skcipher_givcrypt_request *skcipher_givcrypt_cast(
62 struct crypto_async_request *req)
63{
64 return container_of(ablkcipher_request_cast(req),
65 struct skcipher_givcrypt_request, creq);
66}
67
68static inline struct skcipher_givcrypt_request *skcipher_givcrypt_alloc(
69 struct crypto_ablkcipher *tfm, gfp_t gfp)
70{
71 struct skcipher_givcrypt_request *req;
72
73 req = kmalloc(sizeof(struct skcipher_givcrypt_request) +
74 crypto_ablkcipher_reqsize(tfm), gfp);
75
76 if (likely(req))
77 skcipher_givcrypt_set_tfm(req, tfm);
78
79 return req;
80}
81
82static inline void skcipher_givcrypt_free(struct skcipher_givcrypt_request *req)
83{
84 kfree(req);
85}
86
87static inline void skcipher_givcrypt_set_callback(
88 struct skcipher_givcrypt_request *req, u32 flags,
89 crypto_completion_t complete, void *data)
90{
91 ablkcipher_request_set_callback(&req->creq, flags, complete, data);
92}
93
94static inline void skcipher_givcrypt_set_crypt(
95 struct skcipher_givcrypt_request *req,
96 struct scatterlist *src, struct scatterlist *dst,
97 unsigned int nbytes, void *iv)
98{
99 ablkcipher_request_set_crypt(&req->creq, src, dst, nbytes, iv);
100}
101
102static inline void skcipher_givcrypt_set_giv(
103 struct skcipher_givcrypt_request *req, u8 *giv, u64 seq)
104{
105 req->giv = giv;
106 req->seq = seq;
107}
108
109#endif /* _CRYPTO_SKCIPHER_H */
110
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