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
29 struct 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 */
40 struct 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
53 struct crypto_skcipher {
54 unsigned int reqsize;
55
56 struct crypto_tfm base;
57 };
58
59 struct crypto_sync_skcipher {
60 struct crypto_skcipher base;
61 };
62
63 struct 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 }
95 struct 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 */
151 struct 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 */
202 struct 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
258 static 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 */
278 struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
279 u32 type, u32 mask);
280
281 struct 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 */
299 struct crypto_lskcipher *crypto_alloc_lskcipher(const char *alg_name,
300 u32 type, u32 mask);
301
302 static inline struct crypto_tfm *crypto_skcipher_tfm(
303 struct crypto_skcipher *tfm)
304 {
305 return &tfm->base;
306 }
307
308 static 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 */
320 static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
321 {
322 crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
323 }
324
325 static 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 */
336 static 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 */
351 int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask);
352
353 static 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
359 static 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
365 static 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
372 static 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
379 static 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 */
395 static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
396 {
397 return crypto_skcipher_alg_common(tfm)->ivsize;
398 }
399
400 static 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 */
415 static 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 */
431 static 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 */
447 static 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 */
464 static 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 */
481 static 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 */
498 static 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 */
515 static inline unsigned int crypto_lskcipher_statesize(
516 struct crypto_lskcipher *tfm)
517 {
518 return crypto_lskcipher_alg(tfm)->co.statesize;
519 }
520
521 static inline unsigned int crypto_sync_skcipher_blocksize(
522 struct crypto_sync_skcipher *tfm)
523 {
524 return crypto_skcipher_blocksize(&tfm->base);
525 }
526
527 static inline unsigned int crypto_skcipher_alignmask(
528 struct crypto_skcipher *tfm)
529 {
530 return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
531 }
532
533 static inline unsigned int crypto_lskcipher_alignmask(
534 struct crypto_lskcipher *tfm)
535 {
536 return crypto_tfm_alg_alignmask(crypto_lskcipher_tfm(tfm));
537 }
538
539 static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
540 {
541 return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
542 }
543
544 static 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
550 static 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
556 static inline u32 crypto_sync_skcipher_get_flags(
557 struct crypto_sync_skcipher *tfm)
558 {
559 return crypto_skcipher_get_flags(&tfm->base);
560 }
561
562 static 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
568 static 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
574 static inline u32 crypto_lskcipher_get_flags(struct crypto_lskcipher *tfm)
575 {
576 return crypto_tfm_get_flags(crypto_lskcipher_tfm(tfm));
577 }
578
579 static 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
585 static 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 */
607 int crypto_skcipher_setkey(struct crypto_skcipher *tfm,
608 const u8 *key, unsigned int keylen);
609
610 static 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 */
632 int crypto_lskcipher_setkey(struct crypto_lskcipher *tfm,
633 const u8 *key, unsigned int keylen);
634
635 static inline unsigned int crypto_skcipher_min_keysize(
636 struct crypto_skcipher *tfm)
637 {
638 return crypto_skcipher_alg_common(tfm)->min_keysize;
639 }
640
641 static inline unsigned int crypto_skcipher_max_keysize(
642 struct crypto_skcipher *tfm)
643 {
644 return crypto_skcipher_alg_common(tfm)->max_keysize;
645 }
646
647 static inline unsigned int crypto_lskcipher_min_keysize(
648 struct crypto_lskcipher *tfm)
649 {
650 return crypto_lskcipher_alg(tfm)->co.min_keysize;
651 }
652
653 static 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 */
668 static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
669 struct skcipher_request *req)
670 {
671 return __crypto_skcipher_cast(req->base.tfm);
672 }
673
674 static 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 */
693 int 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 */
706 int 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 */
724 int 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 */
739 int 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 */
757 int 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 */
777 int 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 */
797 static 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 */
810 static 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
816 static 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
822 static 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 */
839 static 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 */
858 static inline void skcipher_request_free(struct skcipher_request *req)
859 {
860 kfree_sensitive(req);
861 }
862
863 static 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 */
895 static 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 */
921 static 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
934
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