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v6.8
  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 crypto_istat_cipher - statistics for cipher algorithm
 69 * @encrypt_cnt:	number of encrypt requests
 70 * @encrypt_tlen:	total data size handled by encrypt requests
 71 * @decrypt_cnt:	number of decrypt requests
 72 * @decrypt_tlen:	total data size handled by decrypt requests
 73 * @err_cnt:		number of error for cipher requests
 74 */
 75struct crypto_istat_cipher {
 76	atomic64_t encrypt_cnt;
 77	atomic64_t encrypt_tlen;
 78	atomic64_t decrypt_cnt;
 79	atomic64_t decrypt_tlen;
 80	atomic64_t err_cnt;
 81};
 82
 83#ifdef CONFIG_CRYPTO_STATS
 84#define SKCIPHER_ALG_COMMON_STAT struct crypto_istat_cipher stat;
 85#else
 86#define SKCIPHER_ALG_COMMON_STAT
 87#endif
 88
 89/*
 90 * struct skcipher_alg_common - common properties of skcipher_alg
 91 * @min_keysize: Minimum key size supported by the transformation. This is the
 92 *		 smallest key length supported by this transformation algorithm.
 93 *		 This must be set to one of the pre-defined values as this is
 94 *		 not hardware specific. Possible values for this field can be
 95 *		 found via git grep "_MIN_KEY_SIZE" include/crypto/
 96 * @max_keysize: Maximum key size supported by the transformation. This is the
 97 *		 largest key length supported by this transformation algorithm.
 98 *		 This must be set to one of the pre-defined values as this is
 99 *		 not hardware specific. Possible values for this field can be
100 *		 found via git grep "_MAX_KEY_SIZE" include/crypto/
101 * @ivsize: IV size applicable for transformation. The consumer must provide an
102 *	    IV of exactly that size to perform the encrypt or decrypt operation.
103 * @chunksize: Equal to the block size except for stream ciphers such as
104 *	       CTR where it is set to the underlying block size.
105 * @statesize: Size of the internal state for the algorithm.
106 * @stat: Statistics for cipher algorithm
107 * @base: Definition of a generic crypto algorithm.
108 */
109#define SKCIPHER_ALG_COMMON {		\
110	unsigned int min_keysize;	\
111	unsigned int max_keysize;	\
112	unsigned int ivsize;		\
113	unsigned int chunksize;		\
114	unsigned int statesize;		\
115					\
116	SKCIPHER_ALG_COMMON_STAT	\
117					\
118	struct crypto_alg base;		\
119}
120struct skcipher_alg_common SKCIPHER_ALG_COMMON;
121
122/**
123 * struct skcipher_alg - symmetric key cipher definition
124 * @setkey: Set key for the transformation. This function is used to either
125 *	    program a supplied key into the hardware or store the key in the
126 *	    transformation context for programming it later. Note that this
127 *	    function does modify the transformation context. This function can
128 *	    be called multiple times during the existence of the transformation
129 *	    object, so one must make sure the key is properly reprogrammed into
130 *	    the hardware. This function is also responsible for checking the key
131 *	    length for validity. In case a software fallback was put in place in
132 *	    the @cra_init call, this function might need to use the fallback if
133 *	    the algorithm doesn't support all of the key sizes.
134 * @encrypt: Encrypt a scatterlist of blocks. This function is used to encrypt
135 *	     the supplied scatterlist containing the blocks of data. The crypto
136 *	     API consumer is responsible for aligning the entries of the
137 *	     scatterlist properly and making sure the chunks are correctly
138 *	     sized. In case a software fallback was put in place in the
139 *	     @cra_init call, this function might need to use the fallback if
140 *	     the algorithm doesn't support all of the key sizes. In case the
141 *	     key was stored in transformation context, the key might need to be
142 *	     re-programmed into the hardware in this function. This function
143 *	     shall not modify the transformation context, as this function may
144 *	     be called in parallel with the same transformation object.
145 * @decrypt: Decrypt a single block. This is a reverse counterpart to @encrypt
146 *	     and the conditions are exactly the same.
147 * @export: Export partial state of the transformation. This function dumps the
148 *	    entire state of the ongoing transformation into a provided block of
149 *	    data so it can be @import 'ed back later on. This is useful in case
150 *	    you want to save partial result of the transformation after
151 *	    processing certain amount of data and reload this partial result
152 *	    multiple times later on for multiple re-use. No data processing
153 *	    happens at this point.
154 * @import: Import partial state of the transformation. This function loads the
155 *	    entire state of the ongoing transformation from a provided block of
156 *	    data so the transformation can continue from this point onward. No
157 *	    data processing happens at this point.
158 * @init: Initialize the cryptographic transformation object. This function
159 *	  is used to initialize the cryptographic transformation object.
160 *	  This function is called only once at the instantiation time, right
161 *	  after the transformation context was allocated. In case the
162 *	  cryptographic hardware has some special requirements which need to
163 *	  be handled by software, this function shall check for the precise
164 *	  requirement of the transformation and put any software fallbacks
165 *	  in place.
166 * @exit: Deinitialize the cryptographic transformation object. This is a
167 *	  counterpart to @init, used to remove various changes set in
168 *	  @init.
169 * @walksize: Equal to the chunk size except in cases where the algorithm is
170 * 	      considerably more efficient if it can operate on multiple chunks
171 * 	      in parallel. Should be a multiple of chunksize.
172 * @co: see struct skcipher_alg_common
173 *
174 * All fields except @ivsize are mandatory and must be filled.
175 */
176struct skcipher_alg {
177	int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
178	              unsigned int keylen);
179	int (*encrypt)(struct skcipher_request *req);
180	int (*decrypt)(struct skcipher_request *req);
181	int (*export)(struct skcipher_request *req, void *out);
182	int (*import)(struct skcipher_request *req, const void *in);
183	int (*init)(struct crypto_skcipher *tfm);
184	void (*exit)(struct crypto_skcipher *tfm);
185
186	unsigned int walksize;
187
188	union {
189		struct SKCIPHER_ALG_COMMON;
190		struct skcipher_alg_common co;
191	};
192};
193
194/**
195 * struct lskcipher_alg - linear symmetric key cipher definition
196 * @setkey: Set key for the transformation. This function is used to either
197 *	    program a supplied key into the hardware or store the key in the
198 *	    transformation context for programming it later. Note that this
199 *	    function does modify the transformation context. This function can
200 *	    be called multiple times during the existence of the transformation
201 *	    object, so one must make sure the key is properly reprogrammed into
202 *	    the hardware. This function is also responsible for checking the key
203 *	    length for validity. In case a software fallback was put in place in
204 *	    the @cra_init call, this function might need to use the fallback if
205 *	    the algorithm doesn't support all of the key sizes.
206 * @encrypt: Encrypt a number of bytes. This function is used to encrypt
207 *	     the supplied data.  This function shall not modify
208 *	     the transformation context, as this function may be called
209 *	     in parallel with the same transformation object.  Data
210 *	     may be left over if length is not a multiple of blocks
211 *	     and there is more to come (final == false).  The number of
212 *	     left-over bytes should be returned in case of success.
213 *	     The siv field shall be as long as ivsize + statesize with
214 *	     the IV placed at the front.  The state will be used by the
215 *	     algorithm internally.
216 * @decrypt: Decrypt a number of bytes. This is a reverse counterpart to
217 *	     @encrypt and the conditions are exactly the same.
218 * @init: Initialize the cryptographic transformation object. This function
219 *	  is used to initialize the cryptographic transformation object.
220 *	  This function is called only once at the instantiation time, right
221 *	  after the transformation context was allocated.
222 * @exit: Deinitialize the cryptographic transformation object. This is a
223 *	  counterpart to @init, used to remove various changes set in
224 *	  @init.
225 * @co: see struct skcipher_alg_common
226 */
227struct lskcipher_alg {
228	int (*setkey)(struct crypto_lskcipher *tfm, const u8 *key,
229	              unsigned int keylen);
230	int (*encrypt)(struct crypto_lskcipher *tfm, const u8 *src,
231		       u8 *dst, unsigned len, u8 *siv, u32 flags);
232	int (*decrypt)(struct crypto_lskcipher *tfm, const u8 *src,
233		       u8 *dst, unsigned len, u8 *siv, u32 flags);
234	int (*init)(struct crypto_lskcipher *tfm);
235	void (*exit)(struct crypto_lskcipher *tfm);
236
237	struct skcipher_alg_common co;
238};
239
240#define MAX_SYNC_SKCIPHER_REQSIZE      384
241/*
242 * This performs a type-check against the "tfm" argument to make sure
243 * all users have the correct skcipher tfm for doing on-stack requests.
244 */
245#define SYNC_SKCIPHER_REQUEST_ON_STACK(name, tfm) \
246	char __##name##_desc[sizeof(struct skcipher_request) + \
247			     MAX_SYNC_SKCIPHER_REQSIZE + \
248			     (!(sizeof((struct crypto_sync_skcipher *)1 == \
249				       (typeof(tfm))1))) \
250			    ] CRYPTO_MINALIGN_ATTR; \
251	struct skcipher_request *name = (void *)__##name##_desc
252
253/**
254 * DOC: Symmetric Key Cipher API
255 *
256 * Symmetric key cipher API is used with the ciphers of type
257 * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto).
258 *
259 * Asynchronous cipher operations imply that the function invocation for a
260 * cipher request returns immediately before the completion of the operation.
261 * The cipher request is scheduled as a separate kernel thread and therefore
262 * load-balanced on the different CPUs via the process scheduler. To allow
263 * the kernel crypto API to inform the caller about the completion of a cipher
264 * request, the caller must provide a callback function. That function is
265 * invoked with the cipher handle when the request completes.
266 *
267 * To support the asynchronous operation, additional information than just the
268 * cipher handle must be supplied to the kernel crypto API. That additional
269 * information is given by filling in the skcipher_request data structure.
270 *
271 * For the symmetric key cipher API, the state is maintained with the tfm
272 * cipher handle. A single tfm can be used across multiple calls and in
273 * parallel. For asynchronous block cipher calls, context data supplied and
274 * only used by the caller can be referenced the request data structure in
275 * addition to the IV used for the cipher request. The maintenance of such
276 * state information would be important for a crypto driver implementer to
277 * have, because when calling the callback function upon completion of the
278 * cipher operation, that callback function may need some information about
279 * which operation just finished if it invoked multiple in parallel. This
280 * state information is unused by the kernel crypto API.
281 */
282
283static inline struct crypto_skcipher *__crypto_skcipher_cast(
284	struct crypto_tfm *tfm)
285{
286	return container_of(tfm, struct crypto_skcipher, base);
287}
288
289/**
290 * crypto_alloc_skcipher() - allocate symmetric key cipher handle
291 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
292 *	      skcipher cipher
293 * @type: specifies the type of the cipher
294 * @mask: specifies the mask for the cipher
295 *
296 * Allocate a cipher handle for an skcipher. The returned struct
297 * crypto_skcipher is the cipher handle that is required for any subsequent
298 * API invocation for that skcipher.
299 *
300 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
301 *	   of an error, PTR_ERR() returns the error code.
302 */
303struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name,
304					      u32 type, u32 mask);
305
306struct crypto_sync_skcipher *crypto_alloc_sync_skcipher(const char *alg_name,
307					      u32 type, u32 mask);
308
309
310/**
311 * crypto_alloc_lskcipher() - allocate linear symmetric key cipher handle
312 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
313 *	      lskcipher
314 * @type: specifies the type of the cipher
315 * @mask: specifies the mask for the cipher
316 *
317 * Allocate a cipher handle for an lskcipher. The returned struct
318 * crypto_lskcipher is the cipher handle that is required for any subsequent
319 * API invocation for that lskcipher.
320 *
321 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
322 *	   of an error, PTR_ERR() returns the error code.
323 */
324struct crypto_lskcipher *crypto_alloc_lskcipher(const char *alg_name,
325						u32 type, u32 mask);
326
327static inline struct crypto_tfm *crypto_skcipher_tfm(
328	struct crypto_skcipher *tfm)
329{
330	return &tfm->base;
331}
332
333static inline struct crypto_tfm *crypto_lskcipher_tfm(
334	struct crypto_lskcipher *tfm)
335{
336	return &tfm->base;
337}
338
339/**
340 * crypto_free_skcipher() - zeroize and free cipher handle
341 * @tfm: cipher handle to be freed
342 *
343 * If @tfm is a NULL or error pointer, this function does nothing.
344 */
345static inline void crypto_free_skcipher(struct crypto_skcipher *tfm)
346{
347	crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm));
348}
349
350static inline void crypto_free_sync_skcipher(struct crypto_sync_skcipher *tfm)
351{
352	crypto_free_skcipher(&tfm->base);
353}
354
355/**
356 * crypto_free_lskcipher() - zeroize and free cipher handle
357 * @tfm: cipher handle to be freed
358 *
359 * If @tfm is a NULL or error pointer, this function does nothing.
360 */
361static inline void crypto_free_lskcipher(struct crypto_lskcipher *tfm)
362{
363	crypto_destroy_tfm(tfm, crypto_lskcipher_tfm(tfm));
364}
365
366/**
367 * crypto_has_skcipher() - Search for the availability of an skcipher.
368 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
369 *	      skcipher
370 * @type: specifies the type of the skcipher
371 * @mask: specifies the mask for the skcipher
372 *
373 * Return: true when the skcipher is known to the kernel crypto API; false
374 *	   otherwise
375 */
376int crypto_has_skcipher(const char *alg_name, u32 type, u32 mask);
377
378static inline const char *crypto_skcipher_driver_name(
379	struct crypto_skcipher *tfm)
380{
381	return crypto_tfm_alg_driver_name(crypto_skcipher_tfm(tfm));
382}
383
384static inline const char *crypto_lskcipher_driver_name(
385	struct crypto_lskcipher *tfm)
386{
387	return crypto_tfm_alg_driver_name(crypto_lskcipher_tfm(tfm));
388}
389
390static inline struct skcipher_alg_common *crypto_skcipher_alg_common(
391	struct crypto_skcipher *tfm)
392{
393	return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
394			    struct skcipher_alg_common, base);
395}
396
397static inline struct skcipher_alg *crypto_skcipher_alg(
398	struct crypto_skcipher *tfm)
399{
400	return container_of(crypto_skcipher_tfm(tfm)->__crt_alg,
401			    struct skcipher_alg, base);
402}
403
404static inline struct lskcipher_alg *crypto_lskcipher_alg(
405	struct crypto_lskcipher *tfm)
406{
407	return container_of(crypto_lskcipher_tfm(tfm)->__crt_alg,
408			    struct lskcipher_alg, co.base);
409}
410
411/**
412 * crypto_skcipher_ivsize() - obtain IV size
413 * @tfm: cipher handle
414 *
415 * The size of the IV for the skcipher referenced by the cipher handle is
416 * returned. This IV size may be zero if the cipher does not need an IV.
417 *
418 * Return: IV size in bytes
419 */
420static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm)
421{
422	return crypto_skcipher_alg_common(tfm)->ivsize;
423}
424
425static inline unsigned int crypto_sync_skcipher_ivsize(
426	struct crypto_sync_skcipher *tfm)
427{
428	return crypto_skcipher_ivsize(&tfm->base);
429}
430
431/**
432 * crypto_lskcipher_ivsize() - obtain IV size
433 * @tfm: cipher handle
434 *
435 * The size of the IV for the lskcipher referenced by the cipher handle is
436 * returned. This IV size may be zero if the cipher does not need an IV.
437 *
438 * Return: IV size in bytes
439 */
440static inline unsigned int crypto_lskcipher_ivsize(
441	struct crypto_lskcipher *tfm)
442{
443	return crypto_lskcipher_alg(tfm)->co.ivsize;
444}
445
446/**
447 * crypto_skcipher_blocksize() - obtain block size of cipher
448 * @tfm: cipher handle
449 *
450 * The block size for the skcipher referenced with the cipher handle is
451 * returned. The caller may use that information to allocate appropriate
452 * memory for the data returned by the encryption or decryption operation
453 *
454 * Return: block size of cipher
455 */
456static inline unsigned int crypto_skcipher_blocksize(
457	struct crypto_skcipher *tfm)
458{
459	return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm));
460}
461
462/**
463 * crypto_lskcipher_blocksize() - obtain block size of cipher
464 * @tfm: cipher handle
465 *
466 * The block size for the lskcipher referenced with the cipher handle is
467 * returned. The caller may use that information to allocate appropriate
468 * memory for the data returned by the encryption or decryption operation
469 *
470 * Return: block size of cipher
471 */
472static inline unsigned int crypto_lskcipher_blocksize(
473	struct crypto_lskcipher *tfm)
474{
475	return crypto_tfm_alg_blocksize(crypto_lskcipher_tfm(tfm));
476}
477
478/**
479 * crypto_skcipher_chunksize() - obtain chunk size
480 * @tfm: cipher handle
481 *
482 * The block size is set to one for ciphers such as CTR.  However,
483 * you still need to provide incremental updates in multiples of
484 * the underlying block size as the IV does not have sub-block
485 * granularity.  This is known in this API as the chunk size.
486 *
487 * Return: chunk size in bytes
488 */
489static inline unsigned int crypto_skcipher_chunksize(
490	struct crypto_skcipher *tfm)
491{
492	return crypto_skcipher_alg_common(tfm)->chunksize;
493}
494
495/**
496 * crypto_lskcipher_chunksize() - obtain chunk size
497 * @tfm: cipher handle
498 *
499 * The block size is set to one for ciphers such as CTR.  However,
500 * you still need to provide incremental updates in multiples of
501 * the underlying block size as the IV does not have sub-block
502 * granularity.  This is known in this API as the chunk size.
503 *
504 * Return: chunk size in bytes
505 */
506static inline unsigned int crypto_lskcipher_chunksize(
507	struct crypto_lskcipher *tfm)
508{
509	return crypto_lskcipher_alg(tfm)->co.chunksize;
510}
511
512/**
513 * crypto_skcipher_statesize() - obtain state size
514 * @tfm: cipher handle
515 *
516 * Some algorithms cannot be chained with the IV alone.  They carry
517 * internal state which must be replicated if data is to be processed
518 * incrementally.  The size of that state can be obtained with this
519 * function.
520 *
521 * Return: state size in bytes
522 */
523static inline unsigned int crypto_skcipher_statesize(
524	struct crypto_skcipher *tfm)
525{
526	return crypto_skcipher_alg_common(tfm)->statesize;
527}
528
529/**
530 * crypto_lskcipher_statesize() - obtain state size
531 * @tfm: cipher handle
532 *
533 * Some algorithms cannot be chained with the IV alone.  They carry
534 * internal state which must be replicated if data is to be processed
535 * incrementally.  The size of that state can be obtained with this
536 * function.
537 *
538 * Return: state size in bytes
539 */
540static inline unsigned int crypto_lskcipher_statesize(
541	struct crypto_lskcipher *tfm)
542{
543	return crypto_lskcipher_alg(tfm)->co.statesize;
544}
545
546static inline unsigned int crypto_sync_skcipher_blocksize(
547	struct crypto_sync_skcipher *tfm)
548{
549	return crypto_skcipher_blocksize(&tfm->base);
550}
551
552static inline unsigned int crypto_skcipher_alignmask(
553	struct crypto_skcipher *tfm)
554{
555	return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm));
556}
557
558static inline unsigned int crypto_lskcipher_alignmask(
559	struct crypto_lskcipher *tfm)
560{
561	return crypto_tfm_alg_alignmask(crypto_lskcipher_tfm(tfm));
562}
563
564static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm)
565{
566	return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm));
567}
568
569static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm,
570					       u32 flags)
571{
572	crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags);
573}
574
575static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm,
576						 u32 flags)
577{
578	crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags);
579}
580
581static inline u32 crypto_sync_skcipher_get_flags(
582	struct crypto_sync_skcipher *tfm)
583{
584	return crypto_skcipher_get_flags(&tfm->base);
585}
586
587static inline void crypto_sync_skcipher_set_flags(
588	struct crypto_sync_skcipher *tfm, u32 flags)
589{
590	crypto_skcipher_set_flags(&tfm->base, flags);
591}
592
593static inline void crypto_sync_skcipher_clear_flags(
594	struct crypto_sync_skcipher *tfm, u32 flags)
595{
596	crypto_skcipher_clear_flags(&tfm->base, flags);
597}
598
599static inline u32 crypto_lskcipher_get_flags(struct crypto_lskcipher *tfm)
600{
601	return crypto_tfm_get_flags(crypto_lskcipher_tfm(tfm));
602}
603
604static inline void crypto_lskcipher_set_flags(struct crypto_lskcipher *tfm,
605					       u32 flags)
606{
607	crypto_tfm_set_flags(crypto_lskcipher_tfm(tfm), flags);
608}
609
610static inline void crypto_lskcipher_clear_flags(struct crypto_lskcipher *tfm,
611						 u32 flags)
612{
613	crypto_tfm_clear_flags(crypto_lskcipher_tfm(tfm), flags);
614}
615
616/**
617 * crypto_skcipher_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 skcipher 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_skcipher_setkey(struct crypto_skcipher *tfm,
633			   const u8 *key, unsigned int keylen);
634
635static inline int crypto_sync_skcipher_setkey(struct crypto_sync_skcipher *tfm,
636					 const u8 *key, unsigned int keylen)
637{
638	return crypto_skcipher_setkey(&tfm->base, key, keylen);
639}
640
641/**
642 * crypto_lskcipher_setkey() - set key for cipher
643 * @tfm: cipher handle
644 * @key: buffer holding the key
645 * @keylen: length of the key in bytes
646 *
647 * The caller provided key is set for the lskcipher referenced by the cipher
648 * handle.
649 *
650 * Note, the key length determines the cipher type. Many block ciphers implement
651 * different cipher modes depending on the key size, such as AES-128 vs AES-192
652 * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
653 * is performed.
654 *
655 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
656 */
657int crypto_lskcipher_setkey(struct crypto_lskcipher *tfm,
658			    const u8 *key, unsigned int keylen);
659
660static inline unsigned int crypto_skcipher_min_keysize(
661	struct crypto_skcipher *tfm)
662{
663	return crypto_skcipher_alg_common(tfm)->min_keysize;
664}
665
666static inline unsigned int crypto_skcipher_max_keysize(
667	struct crypto_skcipher *tfm)
668{
669	return crypto_skcipher_alg_common(tfm)->max_keysize;
670}
671
672static inline unsigned int crypto_lskcipher_min_keysize(
673	struct crypto_lskcipher *tfm)
674{
675	return crypto_lskcipher_alg(tfm)->co.min_keysize;
676}
677
678static inline unsigned int crypto_lskcipher_max_keysize(
679	struct crypto_lskcipher *tfm)
680{
681	return crypto_lskcipher_alg(tfm)->co.max_keysize;
682}
683
684/**
685 * crypto_skcipher_reqtfm() - obtain cipher handle from request
686 * @req: skcipher_request out of which the cipher handle is to be obtained
687 *
688 * Return the crypto_skcipher handle when furnishing an skcipher_request
689 * data structure.
690 *
691 * Return: crypto_skcipher handle
692 */
693static inline struct crypto_skcipher *crypto_skcipher_reqtfm(
694	struct skcipher_request *req)
695{
696	return __crypto_skcipher_cast(req->base.tfm);
697}
698
699static inline struct crypto_sync_skcipher *crypto_sync_skcipher_reqtfm(
700	struct skcipher_request *req)
701{
702	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
703
704	return container_of(tfm, struct crypto_sync_skcipher, base);
705}
706
707/**
708 * crypto_skcipher_encrypt() - encrypt plaintext
709 * @req: reference to the skcipher_request handle that holds all information
710 *	 needed to perform the cipher operation
711 *
712 * Encrypt plaintext data using the skcipher_request handle. That data
713 * structure and how it is filled with data is discussed with the
714 * skcipher_request_* functions.
715 *
716 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
717 */
718int crypto_skcipher_encrypt(struct skcipher_request *req);
719
720/**
721 * crypto_skcipher_decrypt() - decrypt ciphertext
722 * @req: reference to the skcipher_request handle that holds all information
723 *	 needed to perform the cipher operation
724 *
725 * Decrypt ciphertext data using the skcipher_request handle. That data
726 * structure and how it is filled with data is discussed with the
727 * skcipher_request_* functions.
728 *
729 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
730 */
731int crypto_skcipher_decrypt(struct skcipher_request *req);
732
733/**
734 * crypto_skcipher_export() - export partial state
735 * @req: reference to the skcipher_request handle that holds all information
736 *	 needed to perform the operation
737 * @out: output buffer of sufficient size that can hold the state
738 *
739 * Export partial state of the transformation. This function dumps the
740 * entire state of the ongoing transformation into a provided block of
741 * data so it can be @import 'ed back later on. This is useful in case
742 * you want to save partial result of the transformation after
743 * processing certain amount of data and reload this partial result
744 * multiple times later on for multiple re-use. No data processing
745 * happens at this point.
746 *
747 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
748 */
749int crypto_skcipher_export(struct skcipher_request *req, void *out);
750
751/**
752 * crypto_skcipher_import() - import partial state
753 * @req: reference to the skcipher_request handle that holds all information
754 *	 needed to perform the operation
755 * @in: buffer holding the state
756 *
757 * Import partial state of the transformation. This function loads the
758 * entire state of the ongoing transformation from a provided block of
759 * data so the transformation can continue from this point onward. No
760 * data processing happens at this point.
761 *
762 * Return: 0 if the cipher operation was successful; < 0 if an error occurred
763 */
764int crypto_skcipher_import(struct skcipher_request *req, const void *in);
765
766/**
767 * crypto_lskcipher_encrypt() - encrypt plaintext
768 * @tfm: lskcipher handle
769 * @src: source buffer
770 * @dst: destination buffer
771 * @len: number of bytes to process
772 * @siv: IV + state for the cipher operation.  The length of the IV must
773 *	 comply with the IV size defined by crypto_lskcipher_ivsize.  The
774 *	 IV is then followed with a buffer with the length as specified by
775 *	 crypto_lskcipher_statesize.
776 * Encrypt plaintext data using the lskcipher handle.
777 *
778 * Return: >=0 if the cipher operation was successful, if positive
779 *	   then this many bytes have been left unprocessed;
780 *	   < 0 if an error occurred
781 */
782int crypto_lskcipher_encrypt(struct crypto_lskcipher *tfm, const u8 *src,
783			     u8 *dst, unsigned len, u8 *siv);
784
785/**
786 * crypto_lskcipher_decrypt() - decrypt ciphertext
787 * @tfm: lskcipher handle
788 * @src: source buffer
789 * @dst: destination buffer
790 * @len: number of bytes to process
791 * @siv: IV + state for the cipher operation.  The length of the IV must
792 *	 comply with the IV size defined by crypto_lskcipher_ivsize.  The
793 *	 IV is then followed with a buffer with the length as specified by
794 *	 crypto_lskcipher_statesize.
795 *
796 * Decrypt ciphertext data using the lskcipher handle.
797 *
798 * Return: >=0 if the cipher operation was successful, if positive
799 *	   then this many bytes have been left unprocessed;
800 *	   < 0 if an error occurred
801 */
802int crypto_lskcipher_decrypt(struct crypto_lskcipher *tfm, const u8 *src,
803			     u8 *dst, unsigned len, u8 *siv);
804
805/**
806 * DOC: Symmetric Key Cipher Request Handle
807 *
808 * The skcipher_request data structure contains all pointers to data
809 * required for the symmetric key cipher operation. This includes the cipher
810 * handle (which can be used by multiple skcipher_request instances), pointer
811 * to plaintext and ciphertext, asynchronous callback function, etc. It acts
812 * as a handle to the skcipher_request_* API calls in a similar way as
813 * skcipher handle to the crypto_skcipher_* API calls.
814 */
815
816/**
817 * crypto_skcipher_reqsize() - obtain size of the request data structure
818 * @tfm: cipher handle
819 *
820 * Return: number of bytes
821 */
822static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm)
823{
824	return tfm->reqsize;
825}
826
827/**
828 * skcipher_request_set_tfm() - update cipher handle reference in request
829 * @req: request handle to be modified
830 * @tfm: cipher handle that shall be added to the request handle
831 *
832 * Allow the caller to replace the existing skcipher handle in the request
833 * data structure with a different one.
834 */
835static inline void skcipher_request_set_tfm(struct skcipher_request *req,
836					    struct crypto_skcipher *tfm)
837{
838	req->base.tfm = crypto_skcipher_tfm(tfm);
839}
840
841static inline void skcipher_request_set_sync_tfm(struct skcipher_request *req,
842					    struct crypto_sync_skcipher *tfm)
843{
844	skcipher_request_set_tfm(req, &tfm->base);
845}
846
847static inline struct skcipher_request *skcipher_request_cast(
848	struct crypto_async_request *req)
849{
850	return container_of(req, struct skcipher_request, base);
851}
852
853/**
854 * skcipher_request_alloc() - allocate request data structure
855 * @tfm: cipher handle to be registered with the request
856 * @gfp: memory allocation flag that is handed to kmalloc by the API call.
857 *
858 * Allocate the request data structure that must be used with the skcipher
859 * encrypt and decrypt API calls. During the allocation, the provided skcipher
860 * handle is registered in the request data structure.
861 *
862 * Return: allocated request handle in case of success, or NULL if out of memory
863 */
864static inline struct skcipher_request *skcipher_request_alloc(
865	struct crypto_skcipher *tfm, gfp_t gfp)
866{
867	struct skcipher_request *req;
868
869	req = kmalloc(sizeof(struct skcipher_request) +
870		      crypto_skcipher_reqsize(tfm), gfp);
871
872	if (likely(req))
873		skcipher_request_set_tfm(req, tfm);
874
875	return req;
876}
 
877
878/**
879 * skcipher_request_free() - zeroize and free request data structure
880 * @req: request data structure cipher handle to be freed
881 */
882static inline void skcipher_request_free(struct skcipher_request *req)
883{
884	kfree_sensitive(req);
885}
886
887static inline void skcipher_request_zero(struct skcipher_request *req)
888{
889	struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
890
891	memzero_explicit(req, sizeof(*req) + crypto_skcipher_reqsize(tfm));
892}
893
894/**
895 * skcipher_request_set_callback() - set asynchronous callback function
896 * @req: request handle
897 * @flags: specify zero or an ORing of the flags
898 *	   CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and
899 *	   increase the wait queue beyond the initial maximum size;
900 *	   CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep
901 * @compl: callback function pointer to be registered with the request handle
902 * @data: The data pointer refers to memory that is not used by the kernel
903 *	  crypto API, but provided to the callback function for it to use. Here,
904 *	  the caller can provide a reference to memory the callback function can
905 *	  operate on. As the callback function is invoked asynchronously to the
906 *	  related functionality, it may need to access data structures of the
907 *	  related functionality which can be referenced using this pointer. The
908 *	  callback function can access the memory via the "data" field in the
909 *	  crypto_async_request data structure provided to the callback function.
910 *
911 * This function allows setting the callback function that is triggered once the
912 * cipher operation completes.
913 *
914 * The callback function is registered with the skcipher_request handle and
915 * must comply with the following template::
916 *
917 *	void callback_function(struct crypto_async_request *req, int error)
918 */
919static inline void skcipher_request_set_callback(struct skcipher_request *req,
920						 u32 flags,
921						 crypto_completion_t compl,
922						 void *data)
923{
924	req->base.complete = compl;
925	req->base.data = data;
926	req->base.flags = flags;
927}
928
929/**
930 * skcipher_request_set_crypt() - set data buffers
931 * @req: request handle
932 * @src: source scatter / gather list
933 * @dst: destination scatter / gather list
934 * @cryptlen: number of bytes to process from @src
935 * @iv: IV for the cipher operation which must comply with the IV size defined
936 *      by crypto_skcipher_ivsize
937 *
938 * This function allows setting of the source data and destination data
939 * scatter / gather lists.
940 *
941 * For encryption, the source is treated as the plaintext and the
942 * destination is the ciphertext. For a decryption operation, the use is
943 * reversed - the source is the ciphertext and the destination is the plaintext.
944 */
945static inline void skcipher_request_set_crypt(
946	struct skcipher_request *req,
947	struct scatterlist *src, struct scatterlist *dst,
948	unsigned int cryptlen, void *iv)
949{
950	req->src = src;
951	req->dst = dst;
952	req->cryptlen = cryptlen;
953	req->iv = iv;
954}
955
956#endif	/* _CRYPTO_SKCIPHER_H */
957
v6.13.7
  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