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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 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 int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
39 unsigned int keylen);
40 int (*encrypt)(struct skcipher_request *req);
41 int (*decrypt)(struct skcipher_request *req);
42
43 unsigned int ivsize;
44 unsigned int reqsize;
45 unsigned int keysize;
46
47 struct crypto_tfm base;
48};
49
50struct crypto_sync_skcipher {
51 struct crypto_skcipher base;
52};
53
54/**
55 * struct skcipher_alg - symmetric key cipher definition
56 * @min_keysize: Minimum key size supported by the transformation. This is the
57 * smallest key length supported by this transformation algorithm.
58 * This must be set to one of the pre-defined values as this is
59 * not hardware specific. Possible values for this field can be
60 * found via git grep "_MIN_KEY_SIZE" include/crypto/
61 * @max_keysize: Maximum key size supported by the transformation. This is the
62 * largest key length supported by this transformation algorithm.
63 * This must be set to one of the pre-defined values as this is
64 * not hardware specific. Possible values for this field can be
65 * found via git grep "_MAX_KEY_SIZE" include/crypto/
66 * @setkey: Set key for the transformation. This function is used to either
67 * program a supplied key into the hardware or store the key in the
68 * transformation context for programming it later. Note that this
69 * function does modify the transformation context. This function can
70 * be called multiple times during the existence of the transformation
71 * object, so one must make sure the key is properly reprogrammed into
72 * the hardware. This function is also responsible for checking the key
73 * length for validity. In case a software fallback was put in place in
74 * the @cra_init call, this function might need to use the fallback if
75 * the algorithm doesn't support all of the key sizes.
76 * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt
77 * the supplied scatterlist containing the blocks of data. The crypto
78 * API consumer is responsible for aligning the entries of the
79 * scatterlist properly and making sure the chunks are correctly
80 * sized. In case a software fallback was put in place in the
81 * @cra_init call, this function might need to use the fallback if
82 * the algorithm doesn't support all of the key sizes. In case the
83 * key was stored in transformation context, the key might need to be
84 * re-programmed into the hardware in this function. This function
85 * shall not modify the transformation context, as this function may
86 * be called in parallel with the same transformation object.
87 * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt
88 * and the conditions are exactly the same.
89 * @init: Initialize the cryptographic transformation object. This function
90 * is used to initialize the cryptographic transformation object.
91 * This function is called only once at the instantiation time, right
92 * after the transformation context was allocated. In case the
93 * cryptographic hardware has some special requirements which need to
94 * be handled by software, this function shall check for the precise
95 * requirement of the transformation and put any software fallbacks
96 * in place.
97 * @exit: Deinitialize the cryptographic transformation object. This is a
98 * counterpart to @init, used to remove various changes set in
99 * @init.
100 * @ivsize: IV size applicable for transformation. The consumer must provide an
101 * IV of exactly that size to perform the encrypt or decrypt operation.
102 * @chunksize: Equal to the block size except for stream ciphers such as
103 * CTR where it is set to the underlying block size.
104 * @walksize: Equal to the chunk size except in cases where the algorithm is
105 * considerably more efficient if it can operate on multiple chunks
106 * in parallel. Should be a multiple of chunksize.
107 * @base: Definition of a generic crypto algorithm.
108 *
109 * All fields except @ivsize are mandatory and must be filled.
110 */
111struct skcipher_alg {
112 int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
113 unsigned int keylen);
114 int (*encrypt)(struct skcipher_request *req);
115 int (*decrypt)(struct skcipher_request *req);
116 int (*init)(struct crypto_skcipher *tfm);
117 void (*exit)(struct crypto_skcipher *tfm);
118
119 unsigned int min_keysize;
120 unsigned int max_keysize;
121 unsigned int ivsize;
122 unsigned int chunksize;
123 unsigned int walksize;
124
125 struct crypto_alg base;
126};
127
128#define MAX_SYNC_SKCIPHER_REQSIZE 384
129/*
130 * This performs a type-check against the "tfm" argument to make sure
131 * all users have the correct skcipher tfm for doing on-stack requests.
132 */
133#define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \
134 char __##name##_desc[sizeof(struct skcipher_request) + \
135 MAX_SYNC_SKCIPHER_REQSIZE + \
136 (!(sizeof((struct crypto_sync_skcipher *)1 == \
137 (typeof(tfm))1))) \
138 ] CRYPTO_MINALIGN_ATTR; \
139 struct skcipher_request *name = (void *)__##name##_desc
140
141/**
142 * DOC: Symmetric Key Cipher API
143 *
144 * Symmetric key cipher API is used with the ciphers of type
145 * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto).
146 *
147 * Asynchronous cipher operations imply that the function invocation for a
148 * cipher request returns immediately before the completion of the operation.
149 * The cipher request is scheduled as a separate kernel thread and therefore
150 * load-balanced on the different CPUs via the process scheduler. To allow
151 * the kernel crypto API to inform the caller about the completion of a cipher
152 * request, the caller must provide a callback function. That function is
153 * invoked with the cipher handle when the request completes.
154 *
155 * To support the asynchronous operation, additional information than just the
156 * cipher handle must be supplied to the kernel crypto API. That additional
157 * information is given by filling in the skcipher_request data structure.
158 *
159 * For the symmetric key cipher API, the state is maintained with the tfm
160 * cipher handle. A single tfm can be used across multiple calls and in
161 * parallel. For asynchronous block cipher calls, context data supplied and
162 * only used by the caller can be referenced the request data structure in
163 * addition to the IV used for the cipher request. The maintenance of such
164 * state information would be important for a crypto driver implementer to
165 * have, because when calling the callback function upon completion of the
166 * cipher operation, that callback function may need some information about
167 * which operation just finished if it invoked multiple in parallel. This
168 * state information is unused by the kernel crypto API.
169 */
170
171static inline struct crypto_skcipher *__crypto_skcipher_cast(
172 struct crypto_tfm *tfm)
173{
174 return container_of(tfm, struct crypto_skcipher, base);
175}
176
177/**
178 * crypto_alloc_skcipher() - allocate symmetric key cipher handle
179 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
180 * skcipher cipher
181 * @type: specifies the type of the cipher
182 * @mask: specifies the mask for the cipher
183 *
184 * Allocate a cipher handle for an skcipher. The returned struct
185 * crypto_skcipher is the cipher handle that is required for any subsequent
186 * API invocation for that skcipher.
187 *
188 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
189 * of an error, PTR_ERR() returns the error code.
190 */
191struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
192 u32 type, u32 mask);
193
194struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name,
195 u32 type, u32 mask);
196
197static inline struct crypto_tfm *crypto_skcipher_tfm(
198 struct crypto_skcipher *tfm)
199{
200 return &tfm->base;
201}
202
203/**
204 * crypto_free_skcipher() - zeroize and free cipher handle
205 * @tfm: cipher handle to be freed
206 */
207static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
208{
209 crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
210}
211
212static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm)
213{
214 crypto_free_skcipher(&tfm->base);
215}
216
217/**
218 * crypto_has_skcipher() - Search for the availability of an skcipher.
219 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
220 * skcipher
221 * @type: specifies the type of the cipher
222 * @mask: specifies the mask for the cipher
223 *
224 * Return: true when the skcipher is known to the kernel crypto API; false
225 * otherwise
226 */
227static inline int crypto_has_skcipher(const char *alg_name, u32 type,
228 u32 mask)
229{
230 return crypto_has_alg(alg_name, crypto_skcipher_type(type),
231 crypto_skcipher_mask(mask));
232}
233
234/**
235 * crypto_has_skcipher2() - Search for the availability of an skcipher.
236 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
237 * skcipher
238 * @type: specifies the type of the skcipher
239 * @mask: specifies the mask for the skcipher
240 *
241 * Return: true when the skcipher is known to the kernel crypto API; false
242 * otherwise
243 */
244int crypto_has_skcipher2(const char *alg_name, u32 type, u32 mask);
245
246static inline const char *crypto_skcipher_driver_name(
247 struct crypto_skcipher *tfm)
248{
249 return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm));
250}
251
252static inline struct skcipher_alg *crypto_skcipher_alg(
253 struct crypto_skcipher *tfm)
254{
255 return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
256 struct skcipher_alg, base);
257}
258
259static inline unsigned int crypto_skcipher_alg_ivsize(struct skcipher_alg *alg)
260{
261 if ((alg->base.cra_flags & CRYPTO_ALG_TYPE_MASK) ==
262 CRYPTO_ALG_TYPE_BLKCIPHER)
263 return alg->base.cra_blkcipher.ivsize;
264
265 if (alg->base.cra_ablkcipher.encrypt)
266 return alg->base.cra_ablkcipher.ivsize;
267
268 return alg->ivsize;
269}
270
271/**
272 * crypto_skcipher_ivsize() - obtain IV size
273 * @tfm: cipher handle
274 *
275 * The size of the IV for the skcipher referenced by the cipher handle is
276 * returned. This IV size may be zero if the cipher does not need an IV.
277 *
278 * Return: IV size in bytes
279 */
280static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
281{
282 return tfm->ivsize;
283}
284
285static inline unsigned int crypto_sync_skcipher_ivsize(
286 struct crypto_sync_skcipher *tfm)
287{
288 return crypto_skcipher_ivsize(&tfm->base);
289}
290
291/**
292 * crypto_skcipher_blocksize() - obtain block size of cipher
293 * @tfm: cipher handle
294 *
295 * The block size for the skcipher referenced with the cipher handle is
296 * returned. The caller may use that information to allocate appropriate
297 * memory for the data returned by the encryption or decryption operation
298 *
299 * Return: block size of cipher
300 */
301static inline unsigned int crypto_skcipher_blocksize(
302 struct crypto_skcipher *tfm)
303{
304 return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
305}
306
307static inline unsigned int crypto_sync_skcipher_blocksize(
308 struct crypto_sync_skcipher *tfm)
309{
310 return crypto_skcipher_blocksize(&tfm->base);
311}
312
313static inline unsigned int crypto_skcipher_alignmask(
314 struct crypto_skcipher *tfm)
315{
316 return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
317}
318
319static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
320{
321 return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
322}
323
324static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm,
325 u32 flags)
326{
327 crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags);
328}
329
330static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
331 u32 flags)
332{
333 crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
334}
335
336static inline u32 crypto_sync_skcipher_get_flags(
337 struct crypto_sync_skcipher *tfm)
338{
339 return crypto_skcipher_get_flags(&tfm->base);
340}
341
342static inline void crypto_sync_skcipher_set_flags(
343 struct crypto_sync_skcipher *tfm, u32 flags)
344{
345 crypto_skcipher_set_flags(&tfm->base, flags);
346}
347
348static inline void crypto_sync_skcipher_clear_flags(
349 struct crypto_sync_skcipher *tfm, u32 flags)
350{
351 crypto_skcipher_clear_flags(&tfm->base, flags);
352}
353
354/**
355 * crypto_skcipher_setkey() - set key for cipher
356 * @tfm: cipher handle
357 * @key: buffer holding the key
358 * @keylen: length of the key in bytes
359 *
360 * The caller provided key is set for the skcipher referenced by the cipher
361 * handle.
362 *
363 * Note, the key length determines the cipher type. Many block ciphers implement
364 * different cipher modes depending on the key size, such as AES-128 vs AES-192
365 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
366 * is performed.
367 *
368 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
369 */
370static inline int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
371 const u8 *key, unsigned int keylen)
372{
373 return tfm->setkey(tfm, key, keylen);
374}
375
376static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm,
377 const u8 *key, unsigned int keylen)
378{
379 return crypto_skcipher_setkey(&tfm->base, key, keylen);
380}
381
382static inline unsigned int crypto_skcipher_default_keysize(
383 struct crypto_skcipher *tfm)
384{
385 return tfm->keysize;
386}
387
388/**
389 * crypto_skcipher_reqtfm() - obtain cipher handle from request
390 * @req: skcipher_request out of which the cipher handle is to be obtained
391 *
392 * Return the crypto_skcipher handle when furnishing an skcipher_request
393 * data structure.
394 *
395 * Return: crypto_skcipher handle
396 */
397static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
398 struct skcipher_request *req)
399{
400 return __crypto_skcipher_cast(req->base.tfm);
401}
402
403static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm(
404 struct skcipher_request *req)
405{
406 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
407
408 return container_of(tfm, struct crypto_sync_skcipher, base);
409}
410
411/**
412 * crypto_skcipher_encrypt() - encrypt plaintext
413 * @req: reference to the skcipher_request handle that holds all information
414 * needed to perform the cipher operation
415 *
416 * Encrypt plaintext data using the skcipher_request handle. That data
417 * structure and how it is filled with data is discussed with the
418 * skcipher_request_* functions.
419 *
420 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
421 */
422int crypto_skcipher_encrypt(struct skcipher_request *req);
423
424/**
425 * crypto_skcipher_decrypt() - decrypt ciphertext
426 * @req: reference to the skcipher_request handle that holds all information
427 * needed to perform the cipher operation
428 *
429 * Decrypt ciphertext data using the skcipher_request handle. That data
430 * structure and how it is filled with data is discussed with the
431 * skcipher_request_* functions.
432 *
433 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
434 */
435int crypto_skcipher_decrypt(struct skcipher_request *req);
436
437/**
438 * DOC: Symmetric Key Cipher Request Handle
439 *
440 * The skcipher_request data structure contains all pointers to data
441 * required for the symmetric key cipher operation. This includes the cipher
442 * handle (which can be used by multiple skcipher_request instances), pointer
443 * to plaintext and ciphertext, asynchronous callback function, etc. It acts
444 * as a handle to the skcipher_request_* API calls in a similar way as
445 * skcipher handle to the crypto_skcipher_* API calls.
446 */
447
448/**
449 * crypto_skcipher_reqsize() - obtain size of the request data structure
450 * @tfm: cipher handle
451 *
452 * Return: number of bytes
453 */
454static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm)
455{
456 return tfm->reqsize;
457}
458
459/**
460 * skcipher_request_set_tfm() - update cipher handle reference in request
461 * @req: request handle to be modified
462 * @tfm: cipher handle that shall be added to the request handle
463 *
464 * Allow the caller to replace the existing skcipher handle in the request
465 * data structure with a different one.
466 */
467static inline void skcipher_request_set_tfm(struct skcipher_request *req,
468 struct crypto_skcipher *tfm)
469{
470 req->base.tfm = crypto_skcipher_tfm(tfm);
471}
472
473static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req,
474 struct crypto_sync_skcipher *tfm)
475{
476 skcipher_request_set_tfm(req, &tfm->base);
477}
478
479static inline struct skcipher_request *skcipher_request_cast(
480 struct crypto_async_request *req)
481{
482 return container_of(req, struct skcipher_request, base);
483}
484
485/**
486 * skcipher_request_alloc() - allocate request data structure
487 * @tfm: cipher handle to be registered with the request
488 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
489 *
490 * Allocate the request data structure that must be used with the skcipher
491 * encrypt and decrypt API calls. During the allocation, the provided skcipher
492 * handle is registered in the request data structure.
493 *
494 * Return: allocated request handle in case of success, or NULL if out of memory
495 */
496static inline struct skcipher_request *skcipher_request_alloc(
497 struct crypto_skcipher *tfm, gfp_t gfp)
498{
499 struct skcipher_request *req;
500
501 req = kmalloc(sizeof(struct skcipher_request) +
502 crypto_skcipher_reqsize(tfm), gfp);
503
504 if (likely(req))
505 skcipher_request_set_tfm(req, tfm);
506
507 return req;
508}
509
510/**
511 * skcipher_request_free() - zeroize and free request data structure
512 * @req: request data structure cipher handle to be freed
513 */
514static inline void skcipher_request_free(struct skcipher_request *req)
515{
516 kzfree(req);
517}
518
519static inline void skcipher_request_zero(struct skcipher_request *req)
520{
521 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
522
523 memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm));
524}
525
526/**
527 * skcipher_request_set_callback() - set asynchronous callback function
528 * @req: request handle
529 * @flags: specify zero or an ORing of the flags
530 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
531 * increase the wait queue beyond the initial maximum size;
532 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
533 * @compl: callback function pointer to be registered with the request handle
534 * @data: The data pointer refers to memory that is not used by the kernel
535 * crypto API, but provided to the callback function for it to use. Here,
536 * the caller can provide a reference to memory the callback function can
537 * operate on. As the callback function is invoked asynchronously to the
538 * related functionality, it may need to access data structures of the
539 * related functionality which can be referenced using this pointer. The
540 * callback function can access the memory via the "data" field in the
541 * crypto_async_request data structure provided to the callback function.
542 *
543 * This function allows setting the callback function that is triggered once the
544 * cipher operation completes.
545 *
546 * The callback function is registered with the skcipher_request handle and
547 * must comply with the following template::
548 *
549 * void callback_function(struct crypto_async_request *req, int error)
550 */
551static inline void skcipher_request_set_callback(struct skcipher_request *req,
552 u32 flags,
553 crypto_completion_t compl,
554 void *data)
555{
556 req->base.complete = compl;
557 req->base.data = data;
558 req->base.flags = flags;
559}
560
561/**
562 * skcipher_request_set_crypt() - set data buffers
563 * @req: request handle
564 * @src: source scatter / gather list
565 * @dst: destination scatter / gather list
566 * @cryptlen: number of bytes to process from @src
567 * @iv: IV for the cipher operation which must comply with the IV size defined
568 * by crypto_skcipher_ivsize
569 *
570 * This function allows setting of the source data and destination data
571 * scatter / gather lists.
572 *
573 * For encryption, the source is treated as the plaintext and the
574 * destination is the ciphertext. For a decryption operation, the use is
575 * reversed - the source is the ciphertext and the destination is the plaintext.
576 */
577static inline void skcipher_request_set_crypt(
578 struct skcipher_request *req,
579 struct scatterlist *src, struct scatterlist *dst,
580 unsigned int cryptlen, void *iv)
581{
582 req->src = src;
583 req->dst = dst;
584 req->cryptlen = cryptlen;
585 req->iv = iv;
586}
587
588#endif /* _CRYPTO_SKCIPHER_H */
589
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/atomic.h>
12#include <linux/container_of.h>
13#include <linux/crypto.h>
14#include <linux/slab.h>
15#include <linux/string.h>
16#include <linux/types.h>
17
18/* Set this bit if the lskcipher operation is a continuation. */
19#define CRYPTO_LSKCIPHER_FLAG_CONT 0x00000001
20/* Set this bit if the lskcipher operation is final. */
21#define CRYPTO_LSKCIPHER_FLAG_FINAL 0x00000002
22/* The bit CRYPTO_TFM_REQ_MAY_SLEEP can also be set if needed. */
23
24/* Set this bit if the skcipher operation is a continuation. */
25#define CRYPTO_SKCIPHER_REQ_CONT 0x00000001
26/* Set this bit if the skcipher operation is not final. */
27#define CRYPTO_SKCIPHER_REQ_NOTFINAL 0x00000002
28
29struct scatterlist;
30
31/**
32 * struct skcipher_request - Symmetric key cipher request
33 * @cryptlen: Number of bytes to encrypt or decrypt
34 * @iv: Initialisation Vector
35 * @src: Source SG list
36 * @dst: Destination SG list
37 * @base: Underlying async request
38 * @__ctx: Start of private context data
39 */
40struct skcipher_request {
41 unsigned int cryptlen;
42
43 u8 *iv;
44
45 struct scatterlist *src;
46 struct scatterlist *dst;
47
48 struct crypto_async_request base;
49
50 void *__ctx[] CRYPTO_MINALIGN_ATTR;
51};
52
53struct crypto_skcipher {
54 unsigned int reqsize;
55
56 struct crypto_tfm base;
57};
58
59struct crypto_sync_skcipher {
60 struct crypto_skcipher base;
61};
62
63struct crypto_lskcipher {
64 struct crypto_tfm base;
65};
66
67/*
68 * struct skcipher_alg_common - common properties of skcipher_alg
69 * @min_keysize: Minimum key size supported by the transformation. This is the
70 * smallest key length supported by this transformation algorithm.
71 * This must be set to one of the pre-defined values as this is
72 * not hardware specific. Possible values for this field can be
73 * found via git grep "_MIN_KEY_SIZE" include/crypto/
74 * @max_keysize: Maximum key size supported by the transformation. This is the
75 * largest key length supported by this transformation algorithm.
76 * This must be set to one of the pre-defined values as this is
77 * not hardware specific. Possible values for this field can be
78 * found via git grep "_MAX_KEY_SIZE" include/crypto/
79 * @ivsize: IV size applicable for transformation. The consumer must provide an
80 * IV of exactly that size to perform the encrypt or decrypt operation.
81 * @chunksize: Equal to the block size except for stream ciphers such as
82 * CTR where it is set to the underlying block size.
83 * @statesize: Size of the internal state for the algorithm.
84 * @base: Definition of a generic crypto algorithm.
85 */
86#define SKCIPHER_ALG_COMMON { \
87 unsigned int min_keysize; \
88 unsigned int max_keysize; \
89 unsigned int ivsize; \
90 unsigned int chunksize; \
91 unsigned int statesize; \
92 \
93 struct crypto_alg base; \
94}
95struct skcipher_alg_common SKCIPHER_ALG_COMMON;
96
97/**
98 * struct skcipher_alg - symmetric key cipher definition
99 * @setkey: Set key for the transformation. This function is used to either
100 * program a supplied key into the hardware or store the key in the
101 * transformation context for programming it later. Note that this
102 * function does modify the transformation context. This function can
103 * be called multiple times during the existence of the transformation
104 * object, so one must make sure the key is properly reprogrammed into
105 * the hardware. This function is also responsible for checking the key
106 * length for validity. In case a software fallback was put in place in
107 * the @cra_init call, this function might need to use the fallback if
108 * the algorithm doesn't support all of the key sizes.
109 * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt
110 * the supplied scatterlist containing the blocks of data. The crypto
111 * API consumer is responsible for aligning the entries of the
112 * scatterlist properly and making sure the chunks are correctly
113 * sized. In case a software fallback was put in place in the
114 * @cra_init call, this function might need to use the fallback if
115 * the algorithm doesn't support all of the key sizes. In case the
116 * key was stored in transformation context, the key might need to be
117 * re-programmed into the hardware in this function. This function
118 * shall not modify the transformation context, as this function may
119 * be called in parallel with the same transformation object.
120 * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt
121 * and the conditions are exactly the same.
122 * @export: Export partial state of the transformation. This function dumps the
123 * entire state of the ongoing transformation into a provided block of
124 * data so it can be @import 'ed back later on. This is useful in case
125 * you want to save partial result of the transformation after
126 * processing certain amount of data and reload this partial result
127 * multiple times later on for multiple re-use. No data processing
128 * happens at this point.
129 * @import: Import partial state of the transformation. This function loads the
130 * entire state of the ongoing transformation from a provided block of
131 * data so the transformation can continue from this point onward. No
132 * data processing happens at this point.
133 * @init: Initialize the cryptographic transformation object. This function
134 * is used to initialize the cryptographic transformation object.
135 * This function is called only once at the instantiation time, right
136 * after the transformation context was allocated. In case the
137 * cryptographic hardware has some special requirements which need to
138 * be handled by software, this function shall check for the precise
139 * requirement of the transformation and put any software fallbacks
140 * in place.
141 * @exit: Deinitialize the cryptographic transformation object. This is a
142 * counterpart to @init, used to remove various changes set in
143 * @init.
144 * @walksize: Equal to the chunk size except in cases where the algorithm is
145 * considerably more efficient if it can operate on multiple chunks
146 * in parallel. Should be a multiple of chunksize.
147 * @co: see struct skcipher_alg_common
148 *
149 * All fields except @ivsize are mandatory and must be filled.
150 */
151struct skcipher_alg {
152 int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
153 unsigned int keylen);
154 int (*encrypt)(struct skcipher_request *req);
155 int (*decrypt)(struct skcipher_request *req);
156 int (*export)(struct skcipher_request *req, void *out);
157 int (*import)(struct skcipher_request *req, const void *in);
158 int (*init)(struct crypto_skcipher *tfm);
159 void (*exit)(struct crypto_skcipher *tfm);
160
161 unsigned int walksize;
162
163 union {
164 struct SKCIPHER_ALG_COMMON;
165 struct skcipher_alg_common co;
166 };
167};
168
169/**
170 * struct lskcipher_alg - linear symmetric key cipher definition
171 * @setkey: Set key for the transformation. This function is used to either
172 * program a supplied key into the hardware or store the key in the
173 * transformation context for programming it later. Note that this
174 * function does modify the transformation context. This function can
175 * be called multiple times during the existence of the transformation
176 * object, so one must make sure the key is properly reprogrammed into
177 * the hardware. This function is also responsible for checking the key
178 * length for validity. In case a software fallback was put in place in
179 * the @cra_init call, this function might need to use the fallback if
180 * the algorithm doesn't support all of the key sizes.
181 * @encrypt: Encrypt a number of bytes. This function is used to encrypt
182 * the supplied data. This function shall not modify
183 * the transformation context, as this function may be called
184 * in parallel with the same transformation object. Data
185 * may be left over if length is not a multiple of blocks
186 * and there is more to come (final == false). The number of
187 * left-over bytes should be returned in case of success.
188 * The siv field shall be as long as ivsize + statesize with
189 * the IV placed at the front. The state will be used by the
190 * algorithm internally.
191 * @decrypt: Decrypt a number of bytes. This is a reverse counterpart to
192 * @encrypt and the conditions are exactly the same.
193 * @init: Initialize the cryptographic transformation object. This function
194 * is used to initialize the cryptographic transformation object.
195 * This function is called only once at the instantiation time, right
196 * after the transformation context was allocated.
197 * @exit: Deinitialize the cryptographic transformation object. This is a
198 * counterpart to @init, used to remove various changes set in
199 * @init.
200 * @co: see struct skcipher_alg_common
201 */
202struct lskcipher_alg {
203 int (*setkey)(struct crypto_lskcipher *tfm, const u8 *key,
204 unsigned int keylen);
205 int (*encrypt)(struct crypto_lskcipher *tfm, const u8 *src,
206 u8 *dst, unsigned len, u8 *siv, u32 flags);
207 int (*decrypt)(struct crypto_lskcipher *tfm, const u8 *src,
208 u8 *dst, unsigned len, u8 *siv, u32 flags);
209 int (*init)(struct crypto_lskcipher *tfm);
210 void (*exit)(struct crypto_lskcipher *tfm);
211
212 struct skcipher_alg_common co;
213};
214
215#define MAX_SYNC_SKCIPHER_REQSIZE 384
216/*
217 * This performs a type-check against the "tfm" argument to make sure
218 * all users have the correct skcipher tfm for doing on-stack requests.
219 */
220#define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \
221 char __##name##_desc[sizeof(struct skcipher_request) + \
222 MAX_SYNC_SKCIPHER_REQSIZE + \
223 (!(sizeof((struct crypto_sync_skcipher *)1 == \
224 (typeof(tfm))1))) \
225 ] CRYPTO_MINALIGN_ATTR; \
226 struct skcipher_request *name = (void *)__##name##_desc
227
228/**
229 * DOC: Symmetric Key Cipher API
230 *
231 * Symmetric key cipher API is used with the ciphers of type
232 * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto).
233 *
234 * Asynchronous cipher operations imply that the function invocation for a
235 * cipher request returns immediately before the completion of the operation.
236 * The cipher request is scheduled as a separate kernel thread and therefore
237 * load-balanced on the different CPUs via the process scheduler. To allow
238 * the kernel crypto API to inform the caller about the completion of a cipher
239 * request, the caller must provide a callback function. That function is
240 * invoked with the cipher handle when the request completes.
241 *
242 * To support the asynchronous operation, additional information than just the
243 * cipher handle must be supplied to the kernel crypto API. That additional
244 * information is given by filling in the skcipher_request data structure.
245 *
246 * For the symmetric key cipher API, the state is maintained with the tfm
247 * cipher handle. A single tfm can be used across multiple calls and in
248 * parallel. For asynchronous block cipher calls, context data supplied and
249 * only used by the caller can be referenced the request data structure in
250 * addition to the IV used for the cipher request. The maintenance of such
251 * state information would be important for a crypto driver implementer to
252 * have, because when calling the callback function upon completion of the
253 * cipher operation, that callback function may need some information about
254 * which operation just finished if it invoked multiple in parallel. This
255 * state information is unused by the kernel crypto API.
256 */
257
258static inline struct crypto_skcipher *__crypto_skcipher_cast(
259 struct crypto_tfm *tfm)
260{
261 return container_of(tfm, struct crypto_skcipher, base);
262}
263
264/**
265 * crypto_alloc_skcipher() - allocate symmetric key cipher handle
266 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
267 * skcipher cipher
268 * @type: specifies the type of the cipher
269 * @mask: specifies the mask for the cipher
270 *
271 * Allocate a cipher handle for an skcipher. The returned struct
272 * crypto_skcipher is the cipher handle that is required for any subsequent
273 * API invocation for that skcipher.
274 *
275 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
276 * of an error, PTR_ERR() returns the error code.
277 */
278struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
279 u32 type, u32 mask);
280
281struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name,
282 u32 type, u32 mask);
283
284
285/**
286 * crypto_alloc_lskcipher() - allocate linear symmetric key cipher handle
287 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
288 * lskcipher
289 * @type: specifies the type of the cipher
290 * @mask: specifies the mask for the cipher
291 *
292 * Allocate a cipher handle for an lskcipher. The returned struct
293 * crypto_lskcipher is the cipher handle that is required for any subsequent
294 * API invocation for that lskcipher.
295 *
296 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
297 * of an error, PTR_ERR() returns the error code.
298 */
299struct crypto_lskcipher *crypto_alloc_lskcipher(const char *alg_name,
300 u32 type, u32 mask);
301
302static inline struct crypto_tfm *crypto_skcipher_tfm(
303 struct crypto_skcipher *tfm)
304{
305 return &tfm->base;
306}
307
308static inline struct crypto_tfm *crypto_lskcipher_tfm(
309 struct crypto_lskcipher *tfm)
310{
311 return &tfm->base;
312}
313
314/**
315 * crypto_free_skcipher() - zeroize and free cipher handle
316 * @tfm: cipher handle to be freed
317 *
318 * If @tfm is a NULL or error pointer, this function does nothing.
319 */
320static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
321{
322 crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
323}
324
325static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm)
326{
327 crypto_free_skcipher(&tfm->base);
328}
329
330/**
331 * crypto_free_lskcipher() - zeroize and free cipher handle
332 * @tfm: cipher handle to be freed
333 *
334 * If @tfm is a NULL or error pointer, this function does nothing.
335 */
336static inline void crypto_free_lskcipher(struct crypto_lskcipher *tfm)
337{
338 crypto_destroy_tfm(tfm, crypto_lskcipher_tfm(tfm));
339}
340
341/**
342 * crypto_has_skcipher() - Search for the availability of an skcipher.
343 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
344 * skcipher
345 * @type: specifies the type of the skcipher
346 * @mask: specifies the mask for the skcipher
347 *
348 * Return: true when the skcipher is known to the kernel crypto API; false
349 * otherwise
350 */
351int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask);
352
353static inline const char *crypto_skcipher_driver_name(
354 struct crypto_skcipher *tfm)
355{
356 return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm));
357}
358
359static inline const char *crypto_lskcipher_driver_name(
360 struct crypto_lskcipher *tfm)
361{
362 return crypto_tfm_alg_driver_name(crypto_lskcipher_tfm(tfm));
363}
364
365static inline struct skcipher_alg_common *crypto_skcipher_alg_common(
366 struct crypto_skcipher *tfm)
367{
368 return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
369 struct skcipher_alg_common, base);
370}
371
372static inline struct skcipher_alg *crypto_skcipher_alg(
373 struct crypto_skcipher *tfm)
374{
375 return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
376 struct skcipher_alg, base);
377}
378
379static inline struct lskcipher_alg *crypto_lskcipher_alg(
380 struct crypto_lskcipher *tfm)
381{
382 return container_of(crypto_lskcipher_tfm(tfm)->__crt_alg,
383 struct lskcipher_alg, co.base);
384}
385
386/**
387 * crypto_skcipher_ivsize() - obtain IV size
388 * @tfm: cipher handle
389 *
390 * The size of the IV for the skcipher referenced by the cipher handle is
391 * returned. This IV size may be zero if the cipher does not need an IV.
392 *
393 * Return: IV size in bytes
394 */
395static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
396{
397 return crypto_skcipher_alg_common(tfm)->ivsize;
398}
399
400static inline unsigned int crypto_sync_skcipher_ivsize(
401 struct crypto_sync_skcipher *tfm)
402{
403 return crypto_skcipher_ivsize(&tfm->base);
404}
405
406/**
407 * crypto_lskcipher_ivsize() - obtain IV size
408 * @tfm: cipher handle
409 *
410 * The size of the IV for the lskcipher referenced by the cipher handle is
411 * returned. This IV size may be zero if the cipher does not need an IV.
412 *
413 * Return: IV size in bytes
414 */
415static inline unsigned int crypto_lskcipher_ivsize(
416 struct crypto_lskcipher *tfm)
417{
418 return crypto_lskcipher_alg(tfm)->co.ivsize;
419}
420
421/**
422 * crypto_skcipher_blocksize() - obtain block size of cipher
423 * @tfm: cipher handle
424 *
425 * The block size for the skcipher referenced with the cipher handle is
426 * returned. The caller may use that information to allocate appropriate
427 * memory for the data returned by the encryption or decryption operation
428 *
429 * Return: block size of cipher
430 */
431static inline unsigned int crypto_skcipher_blocksize(
432 struct crypto_skcipher *tfm)
433{
434 return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
435}
436
437/**
438 * crypto_lskcipher_blocksize() - obtain block size of cipher
439 * @tfm: cipher handle
440 *
441 * The block size for the lskcipher referenced with the cipher handle is
442 * returned. The caller may use that information to allocate appropriate
443 * memory for the data returned by the encryption or decryption operation
444 *
445 * Return: block size of cipher
446 */
447static inline unsigned int crypto_lskcipher_blocksize(
448 struct crypto_lskcipher *tfm)
449{
450 return crypto_tfm_alg_blocksize(crypto_lskcipher_tfm(tfm));
451}
452
453/**
454 * crypto_skcipher_chunksize() - obtain chunk size
455 * @tfm: cipher handle
456 *
457 * The block size is set to one for ciphers such as CTR. However,
458 * you still need to provide incremental updates in multiples of
459 * the underlying block size as the IV does not have sub-block
460 * granularity. This is known in this API as the chunk size.
461 *
462 * Return: chunk size in bytes
463 */
464static inline unsigned int crypto_skcipher_chunksize(
465 struct crypto_skcipher *tfm)
466{
467 return crypto_skcipher_alg_common(tfm)->chunksize;
468}
469
470/**
471 * crypto_lskcipher_chunksize() - obtain chunk size
472 * @tfm: cipher handle
473 *
474 * The block size is set to one for ciphers such as CTR. However,
475 * you still need to provide incremental updates in multiples of
476 * the underlying block size as the IV does not have sub-block
477 * granularity. This is known in this API as the chunk size.
478 *
479 * Return: chunk size in bytes
480 */
481static inline unsigned int crypto_lskcipher_chunksize(
482 struct crypto_lskcipher *tfm)
483{
484 return crypto_lskcipher_alg(tfm)->co.chunksize;
485}
486
487/**
488 * crypto_skcipher_statesize() - obtain state size
489 * @tfm: cipher handle
490 *
491 * Some algorithms cannot be chained with the IV alone. They carry
492 * internal state which must be replicated if data is to be processed
493 * incrementally. The size of that state can be obtained with this
494 * function.
495 *
496 * Return: state size in bytes
497 */
498static inline unsigned int crypto_skcipher_statesize(
499 struct crypto_skcipher *tfm)
500{
501 return crypto_skcipher_alg_common(tfm)->statesize;
502}
503
504/**
505 * crypto_lskcipher_statesize() - obtain state size
506 * @tfm: cipher handle
507 *
508 * Some algorithms cannot be chained with the IV alone. They carry
509 * internal state which must be replicated if data is to be processed
510 * incrementally. The size of that state can be obtained with this
511 * function.
512 *
513 * Return: state size in bytes
514 */
515static inline unsigned int crypto_lskcipher_statesize(
516 struct crypto_lskcipher *tfm)
517{
518 return crypto_lskcipher_alg(tfm)->co.statesize;
519}
520
521static inline unsigned int crypto_sync_skcipher_blocksize(
522 struct crypto_sync_skcipher *tfm)
523{
524 return crypto_skcipher_blocksize(&tfm->base);
525}
526
527static inline unsigned int crypto_skcipher_alignmask(
528 struct crypto_skcipher *tfm)
529{
530 return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
531}
532
533static inline unsigned int crypto_lskcipher_alignmask(
534 struct crypto_lskcipher *tfm)
535{
536 return crypto_tfm_alg_alignmask(crypto_lskcipher_tfm(tfm));
537}
538
539static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
540{
541 return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
542}
543
544static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm,
545 u32 flags)
546{
547 crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags);
548}
549
550static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
551 u32 flags)
552{
553 crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
554}
555
556static inline u32 crypto_sync_skcipher_get_flags(
557 struct crypto_sync_skcipher *tfm)
558{
559 return crypto_skcipher_get_flags(&tfm->base);
560}
561
562static inline void crypto_sync_skcipher_set_flags(
563 struct crypto_sync_skcipher *tfm, u32 flags)
564{
565 crypto_skcipher_set_flags(&tfm->base, flags);
566}
567
568static inline void crypto_sync_skcipher_clear_flags(
569 struct crypto_sync_skcipher *tfm, u32 flags)
570{
571 crypto_skcipher_clear_flags(&tfm->base, flags);
572}
573
574static inline u32 crypto_lskcipher_get_flags(struct crypto_lskcipher *tfm)
575{
576 return crypto_tfm_get_flags(crypto_lskcipher_tfm(tfm));
577}
578
579static inline void crypto_lskcipher_set_flags(struct crypto_lskcipher *tfm,
580 u32 flags)
581{
582 crypto_tfm_set_flags(crypto_lskcipher_tfm(tfm), flags);
583}
584
585static inline void crypto_lskcipher_clear_flags(struct crypto_lskcipher *tfm,
586 u32 flags)
587{
588 crypto_tfm_clear_flags(crypto_lskcipher_tfm(tfm), flags);
589}
590
591/**
592 * crypto_skcipher_setkey() - set key for cipher
593 * @tfm: cipher handle
594 * @key: buffer holding the key
595 * @keylen: length of the key in bytes
596 *
597 * The caller provided key is set for the skcipher referenced by the cipher
598 * handle.
599 *
600 * Note, the key length determines the cipher type. Many block ciphers implement
601 * different cipher modes depending on the key size, such as AES-128 vs AES-192
602 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
603 * is performed.
604 *
605 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
606 */
607int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
608 const u8 *key, unsigned int keylen);
609
610static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm,
611 const u8 *key, unsigned int keylen)
612{
613 return crypto_skcipher_setkey(&tfm->base, key, keylen);
614}
615
616/**
617 * crypto_lskcipher_setkey() - set key for cipher
618 * @tfm: cipher handle
619 * @key: buffer holding the key
620 * @keylen: length of the key in bytes
621 *
622 * The caller provided key is set for the lskcipher referenced by the cipher
623 * handle.
624 *
625 * Note, the key length determines the cipher type. Many block ciphers implement
626 * different cipher modes depending on the key size, such as AES-128 vs AES-192
627 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
628 * is performed.
629 *
630 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
631 */
632int crypto_lskcipher_setkey(struct crypto_lskcipher *tfm,
633 const u8 *key, unsigned int keylen);
634
635static inline unsigned int crypto_skcipher_min_keysize(
636 struct crypto_skcipher *tfm)
637{
638 return crypto_skcipher_alg_common(tfm)->min_keysize;
639}
640
641static inline unsigned int crypto_skcipher_max_keysize(
642 struct crypto_skcipher *tfm)
643{
644 return crypto_skcipher_alg_common(tfm)->max_keysize;
645}
646
647static inline unsigned int crypto_lskcipher_min_keysize(
648 struct crypto_lskcipher *tfm)
649{
650 return crypto_lskcipher_alg(tfm)->co.min_keysize;
651}
652
653static inline unsigned int crypto_lskcipher_max_keysize(
654 struct crypto_lskcipher *tfm)
655{
656 return crypto_lskcipher_alg(tfm)->co.max_keysize;
657}
658
659/**
660 * crypto_skcipher_reqtfm() - obtain cipher handle from request
661 * @req: skcipher_request out of which the cipher handle is to be obtained
662 *
663 * Return the crypto_skcipher handle when furnishing an skcipher_request
664 * data structure.
665 *
666 * Return: crypto_skcipher handle
667 */
668static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
669 struct skcipher_request *req)
670{
671 return __crypto_skcipher_cast(req->base.tfm);
672}
673
674static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm(
675 struct skcipher_request *req)
676{
677 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
678
679 return container_of(tfm, struct crypto_sync_skcipher, base);
680}
681
682/**
683 * crypto_skcipher_encrypt() - encrypt plaintext
684 * @req: reference to the skcipher_request handle that holds all information
685 * needed to perform the cipher operation
686 *
687 * Encrypt plaintext data using the skcipher_request handle. That data
688 * structure and how it is filled with data is discussed with the
689 * skcipher_request_* functions.
690 *
691 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
692 */
693int crypto_skcipher_encrypt(struct skcipher_request *req);
694
695/**
696 * crypto_skcipher_decrypt() - decrypt ciphertext
697 * @req: reference to the skcipher_request handle that holds all information
698 * needed to perform the cipher operation
699 *
700 * Decrypt ciphertext data using the skcipher_request handle. That data
701 * structure and how it is filled with data is discussed with the
702 * skcipher_request_* functions.
703 *
704 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
705 */
706int crypto_skcipher_decrypt(struct skcipher_request *req);
707
708/**
709 * crypto_skcipher_export() - export partial state
710 * @req: reference to the skcipher_request handle that holds all information
711 * needed to perform the operation
712 * @out: output buffer of sufficient size that can hold the state
713 *
714 * Export partial state of the transformation. This function dumps the
715 * entire state of the ongoing transformation into a provided block of
716 * data so it can be @import 'ed back later on. This is useful in case
717 * you want to save partial result of the transformation after
718 * processing certain amount of data and reload this partial result
719 * multiple times later on for multiple re-use. No data processing
720 * happens at this point.
721 *
722 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
723 */
724int crypto_skcipher_export(struct skcipher_request *req, void *out);
725
726/**
727 * crypto_skcipher_import() - import partial state
728 * @req: reference to the skcipher_request handle that holds all information
729 * needed to perform the operation
730 * @in: buffer holding the state
731 *
732 * Import partial state of the transformation. This function loads the
733 * entire state of the ongoing transformation from a provided block of
734 * data so the transformation can continue from this point onward. No
735 * data processing happens at this point.
736 *
737 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
738 */
739int crypto_skcipher_import(struct skcipher_request *req, const void *in);
740
741/**
742 * crypto_lskcipher_encrypt() - encrypt plaintext
743 * @tfm: lskcipher handle
744 * @src: source buffer
745 * @dst: destination buffer
746 * @len: number of bytes to process
747 * @siv: IV + state for the cipher operation. The length of the IV must
748 * comply with the IV size defined by crypto_lskcipher_ivsize. The
749 * IV is then followed with a buffer with the length as specified by
750 * crypto_lskcipher_statesize.
751 * Encrypt plaintext data using the lskcipher handle.
752 *
753 * Return: >=0 if the cipher operation was successful, if positive
754 * then this many bytes have been left unprocessed;
755 * < 0 if an error occurred
756 */
757int crypto_lskcipher_encrypt(struct crypto_lskcipher *tfm, const u8 *src,
758 u8 *dst, unsigned len, u8 *siv);
759
760/**
761 * crypto_lskcipher_decrypt() - decrypt ciphertext
762 * @tfm: lskcipher handle
763 * @src: source buffer
764 * @dst: destination buffer
765 * @len: number of bytes to process
766 * @siv: IV + state for the cipher operation. The length of the IV must
767 * comply with the IV size defined by crypto_lskcipher_ivsize. The
768 * IV is then followed with a buffer with the length as specified by
769 * crypto_lskcipher_statesize.
770 *
771 * Decrypt ciphertext data using the lskcipher handle.
772 *
773 * Return: >=0 if the cipher operation was successful, if positive
774 * then this many bytes have been left unprocessed;
775 * < 0 if an error occurred
776 */
777int crypto_lskcipher_decrypt(struct crypto_lskcipher *tfm, const u8 *src,
778 u8 *dst, unsigned len, u8 *siv);
779
780/**
781 * DOC: Symmetric Key Cipher Request Handle
782 *
783 * The skcipher_request data structure contains all pointers to data
784 * required for the symmetric key cipher operation. This includes the cipher
785 * handle (which can be used by multiple skcipher_request instances), pointer
786 * to plaintext and ciphertext, asynchronous callback function, etc. It acts
787 * as a handle to the skcipher_request_* API calls in a similar way as
788 * skcipher handle to the crypto_skcipher_* API calls.
789 */
790
791/**
792 * crypto_skcipher_reqsize() - obtain size of the request data structure
793 * @tfm: cipher handle
794 *
795 * Return: number of bytes
796 */
797static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm)
798{
799 return tfm->reqsize;
800}
801
802/**
803 * skcipher_request_set_tfm() - update cipher handle reference in request
804 * @req: request handle to be modified
805 * @tfm: cipher handle that shall be added to the request handle
806 *
807 * Allow the caller to replace the existing skcipher handle in the request
808 * data structure with a different one.
809 */
810static inline void skcipher_request_set_tfm(struct skcipher_request *req,
811 struct crypto_skcipher *tfm)
812{
813 req->base.tfm = crypto_skcipher_tfm(tfm);
814}
815
816static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req,
817 struct crypto_sync_skcipher *tfm)
818{
819 skcipher_request_set_tfm(req, &tfm->base);
820}
821
822static inline struct skcipher_request *skcipher_request_cast(
823 struct crypto_async_request *req)
824{
825 return container_of(req, struct skcipher_request, base);
826}
827
828/**
829 * skcipher_request_alloc() - allocate request data structure
830 * @tfm: cipher handle to be registered with the request
831 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
832 *
833 * Allocate the request data structure that must be used with the skcipher
834 * encrypt and decrypt API calls. During the allocation, the provided skcipher
835 * handle is registered in the request data structure.
836 *
837 * Return: allocated request handle in case of success, or NULL if out of memory
838 */
839static inline struct skcipher_request *skcipher_request_alloc_noprof(
840 struct crypto_skcipher *tfm, gfp_t gfp)
841{
842 struct skcipher_request *req;
843
844 req = kmalloc_noprof(sizeof(struct skcipher_request) +
845 crypto_skcipher_reqsize(tfm), gfp);
846
847 if (likely(req))
848 skcipher_request_set_tfm(req, tfm);
849
850 return req;
851}
852#define skcipher_request_alloc(...) alloc_hooks(skcipher_request_alloc_noprof(__VA_ARGS__))
853
854/**
855 * skcipher_request_free() - zeroize and free request data structure
856 * @req: request data structure cipher handle to be freed
857 */
858static inline void skcipher_request_free(struct skcipher_request *req)
859{
860 kfree_sensitive(req);
861}
862
863static inline void skcipher_request_zero(struct skcipher_request *req)
864{
865 struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
866
867 memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm));
868}
869
870/**
871 * skcipher_request_set_callback() - set asynchronous callback function
872 * @req: request handle
873 * @flags: specify zero or an ORing of the flags
874 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
875 * increase the wait queue beyond the initial maximum size;
876 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
877 * @compl: callback function pointer to be registered with the request handle
878 * @data: The data pointer refers to memory that is not used by the kernel
879 * crypto API, but provided to the callback function for it to use. Here,
880 * the caller can provide a reference to memory the callback function can
881 * operate on. As the callback function is invoked asynchronously to the
882 * related functionality, it may need to access data structures of the
883 * related functionality which can be referenced using this pointer. The
884 * callback function can access the memory via the "data" field in the
885 * crypto_async_request data structure provided to the callback function.
886 *
887 * This function allows setting the callback function that is triggered once the
888 * cipher operation completes.
889 *
890 * The callback function is registered with the skcipher_request handle and
891 * must comply with the following template::
892 *
893 * void callback_function(struct crypto_async_request *req, int error)
894 */
895static inline void skcipher_request_set_callback(struct skcipher_request *req,
896 u32 flags,
897 crypto_completion_t compl,
898 void *data)
899{
900 req->base.complete = compl;
901 req->base.data = data;
902 req->base.flags = flags;
903}
904
905/**
906 * skcipher_request_set_crypt() - set data buffers
907 * @req: request handle
908 * @src: source scatter / gather list
909 * @dst: destination scatter / gather list
910 * @cryptlen: number of bytes to process from @src
911 * @iv: IV for the cipher operation which must comply with the IV size defined
912 * by crypto_skcipher_ivsize
913 *
914 * This function allows setting of the source data and destination data
915 * scatter / gather lists.
916 *
917 * For encryption, the source is treated as the plaintext and the
918 * destination is the ciphertext. For a decryption operation, the use is
919 * reversed - the source is the ciphertext and the destination is the plaintext.
920 */
921static inline void skcipher_request_set_crypt(
922 struct skcipher_request *req,
923 struct scatterlist *src, struct scatterlist *dst,
924 unsigned int cryptlen, void *iv)
925{
926 req->src = src;
927 req->dst = dst;
928 req->cryptlen = cryptlen;
929 req->iv = iv;
930}
931
932#endif /* _CRYPTO_SKCIPHER_H */
933