xref: /linux-6.15/include/linux/crypto.h (revision e2950bf1)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Scatterlist Cryptographic API.
4  *
5  * Copyright (c) 2002 James Morris <[email protected]>
6  * Copyright (c) 2002 David S. Miller ([email protected])
7  * Copyright (c) 2005 Herbert Xu <[email protected]>
8  *
9  * Portions derived from Cryptoapi, by Alexander Kjeldaas <[email protected]>
10  * and Nettle, by Niels Möller.
11  */
12 #ifndef _LINUX_CRYPTO_H
13 #define _LINUX_CRYPTO_H
14 
15 #include <linux/atomic.h>
16 #include <linux/kernel.h>
17 #include <linux/list.h>
18 #include <linux/bug.h>
19 #include <linux/refcount.h>
20 #include <linux/slab.h>
21 #include <linux/completion.h>
22 
23 /*
24  * Autoloaded crypto modules should only use a prefixed name to avoid allowing
25  * arbitrary modules to be loaded. Loading from userspace may still need the
26  * unprefixed names, so retains those aliases as well.
27  * This uses __MODULE_INFO directly instead of MODULE_ALIAS because pre-4.3
28  * gcc (e.g. avr32 toolchain) uses __LINE__ for uniqueness, and this macro
29  * expands twice on the same line. Instead, use a separate base name for the
30  * alias.
31  */
32 #define MODULE_ALIAS_CRYPTO(name)	\
33 		__MODULE_INFO(alias, alias_userspace, name);	\
34 		__MODULE_INFO(alias, alias_crypto, "crypto-" name)
35 
36 /*
37  * Algorithm masks and types.
38  */
39 #define CRYPTO_ALG_TYPE_MASK		0x0000000f
40 #define CRYPTO_ALG_TYPE_CIPHER		0x00000001
41 #define CRYPTO_ALG_TYPE_COMPRESS	0x00000002
42 #define CRYPTO_ALG_TYPE_AEAD		0x00000003
43 #define CRYPTO_ALG_TYPE_SKCIPHER	0x00000005
44 #define CRYPTO_ALG_TYPE_KPP		0x00000008
45 #define CRYPTO_ALG_TYPE_ACOMPRESS	0x0000000a
46 #define CRYPTO_ALG_TYPE_SCOMPRESS	0x0000000b
47 #define CRYPTO_ALG_TYPE_RNG		0x0000000c
48 #define CRYPTO_ALG_TYPE_AKCIPHER	0x0000000d
49 #define CRYPTO_ALG_TYPE_HASH		0x0000000e
50 #define CRYPTO_ALG_TYPE_SHASH		0x0000000e
51 #define CRYPTO_ALG_TYPE_AHASH		0x0000000f
52 
53 #define CRYPTO_ALG_TYPE_HASH_MASK	0x0000000e
54 #define CRYPTO_ALG_TYPE_AHASH_MASK	0x0000000e
55 #define CRYPTO_ALG_TYPE_ACOMPRESS_MASK	0x0000000e
56 
57 #define CRYPTO_ALG_LARVAL		0x00000010
58 #define CRYPTO_ALG_DEAD			0x00000020
59 #define CRYPTO_ALG_DYING		0x00000040
60 #define CRYPTO_ALG_ASYNC		0x00000080
61 
62 /*
63  * Set if the algorithm (or an algorithm which it uses) requires another
64  * algorithm of the same type to handle corner cases.
65  */
66 #define CRYPTO_ALG_NEED_FALLBACK	0x00000100
67 
68 /*
69  * Set if the algorithm has passed automated run-time testing.  Note that
70  * if there is no run-time testing for a given algorithm it is considered
71  * to have passed.
72  */
73 
74 #define CRYPTO_ALG_TESTED		0x00000400
75 
76 /*
77  * Set if the algorithm is an instance that is built from templates.
78  */
79 #define CRYPTO_ALG_INSTANCE		0x00000800
80 
81 /* Set this bit if the algorithm provided is hardware accelerated but
82  * not available to userspace via instruction set or so.
83  */
84 #define CRYPTO_ALG_KERN_DRIVER_ONLY	0x00001000
85 
86 /*
87  * Mark a cipher as a service implementation only usable by another
88  * cipher and never by a normal user of the kernel crypto API
89  */
90 #define CRYPTO_ALG_INTERNAL		0x00002000
91 
92 /*
93  * Set if the algorithm has a ->setkey() method but can be used without
94  * calling it first, i.e. there is a default key.
95  */
96 #define CRYPTO_ALG_OPTIONAL_KEY		0x00004000
97 
98 /*
99  * Don't trigger module loading
100  */
101 #define CRYPTO_NOLOAD			0x00008000
102 
103 /*
104  * The algorithm may allocate memory during request processing, i.e. during
105  * encryption, decryption, or hashing.  Users can request an algorithm with this
106  * flag unset if they can't handle memory allocation failures.
107  *
108  * This flag is currently only implemented for algorithms of type "skcipher",
109  * "aead", "ahash", "shash", and "cipher".  Algorithms of other types might not
110  * have this flag set even if they allocate memory.
111  *
112  * In some edge cases, algorithms can allocate memory regardless of this flag.
113  * To avoid these cases, users must obey the following usage constraints:
114  *    skcipher:
115  *	- The IV buffer and all scatterlist elements must be aligned to the
116  *	  algorithm's alignmask.
117  *	- If the data were to be divided into chunks of size
118  *	  crypto_skcipher_walksize() (with any remainder going at the end), no
119  *	  chunk can cross a page boundary or a scatterlist element boundary.
120  *    aead:
121  *	- The IV buffer and all scatterlist elements must be aligned to the
122  *	  algorithm's alignmask.
123  *	- The first scatterlist element must contain all the associated data,
124  *	  and its pages must be !PageHighMem.
125  *	- If the plaintext/ciphertext were to be divided into chunks of size
126  *	  crypto_aead_walksize() (with the remainder going at the end), no chunk
127  *	  can cross a page boundary or a scatterlist element boundary.
128  *    ahash:
129  *	- The result buffer must be aligned to the algorithm's alignmask.
130  *	- crypto_ahash_finup() must not be used unless the algorithm implements
131  *	  ->finup() natively.
132  */
133 #define CRYPTO_ALG_ALLOCATES_MEMORY	0x00010000
134 
135 /*
136  * Mark an algorithm as a service implementation only usable by a
137  * template and never by a normal user of the kernel crypto API.
138  * This is intended to be used by algorithms that are themselves
139  * not FIPS-approved but may instead be used to implement parts of
140  * a FIPS-approved algorithm (e.g., dh vs. ffdhe2048(dh)).
141  */
142 #define CRYPTO_ALG_FIPS_INTERNAL	0x00020000
143 
144 /*
145  * Transform masks and values (for crt_flags).
146  */
147 #define CRYPTO_TFM_NEED_KEY		0x00000001
148 
149 #define CRYPTO_TFM_REQ_MASK		0x000fff00
150 #define CRYPTO_TFM_REQ_FORBID_WEAK_KEYS	0x00000100
151 #define CRYPTO_TFM_REQ_MAY_SLEEP	0x00000200
152 #define CRYPTO_TFM_REQ_MAY_BACKLOG	0x00000400
153 
154 /*
155  * Miscellaneous stuff.
156  */
157 #define CRYPTO_MAX_ALG_NAME		128
158 
159 /*
160  * The macro CRYPTO_MINALIGN_ATTR (along with the void * type in the actual
161  * declaration) is used to ensure that the crypto_tfm context structure is
162  * aligned correctly for the given architecture so that there are no alignment
163  * faults for C data types.  On architectures that support non-cache coherent
164  * DMA, such as ARM or arm64, it also takes into account the minimal alignment
165  * that is required to ensure that the context struct member does not share any
166  * cachelines with the rest of the struct. This is needed to ensure that cache
167  * maintenance for non-coherent DMA (cache invalidation in particular) does not
168  * affect data that may be accessed by the CPU concurrently.
169  */
170 #define CRYPTO_MINALIGN ARCH_KMALLOC_MINALIGN
171 
172 #define CRYPTO_MINALIGN_ATTR __attribute__ ((__aligned__(CRYPTO_MINALIGN)))
173 
174 struct scatterlist;
175 struct crypto_async_request;
176 struct crypto_tfm;
177 struct crypto_type;
178 
179 typedef void (*crypto_completion_t)(void *req, int err);
180 
181 /**
182  * DOC: Block Cipher Context Data Structures
183  *
184  * These data structures define the operating context for each block cipher
185  * type.
186  */
187 
188 struct crypto_async_request {
189 	struct list_head list;
190 	crypto_completion_t complete;
191 	void *data;
192 	struct crypto_tfm *tfm;
193 
194 	u32 flags;
195 };
196 
197 /**
198  * DOC: Block Cipher Algorithm Definitions
199  *
200  * These data structures define modular crypto algorithm implementations,
201  * managed via crypto_register_alg() and crypto_unregister_alg().
202  */
203 
204 /**
205  * struct cipher_alg - single-block symmetric ciphers definition
206  * @cia_min_keysize: Minimum key size supported by the transformation. This is
207  *		     the smallest key length supported by this transformation
208  *		     algorithm. This must be set to one of the pre-defined
209  *		     values as this is not hardware specific. Possible values
210  *		     for this field can be found via git grep "_MIN_KEY_SIZE"
211  *		     include/crypto/
212  * @cia_max_keysize: Maximum key size supported by the transformation. This is
213  *		    the largest key length supported by this transformation
214  *		    algorithm. This must be set to one of the pre-defined values
215  *		    as this is not hardware specific. Possible values for this
216  *		    field can be found via git grep "_MAX_KEY_SIZE"
217  *		    include/crypto/
218  * @cia_setkey: Set key for the transformation. This function is used to either
219  *	        program a supplied key into the hardware or store the key in the
220  *	        transformation context for programming it later. Note that this
221  *	        function does modify the transformation context. This function
222  *	        can be called multiple times during the existence of the
223  *	        transformation object, so one must make sure the key is properly
224  *	        reprogrammed into the hardware. This function is also
225  *	        responsible for checking the key length for validity.
226  * @cia_encrypt: Encrypt a single block. This function is used to encrypt a
227  *		 single block of data, which must be @cra_blocksize big. This
228  *		 always operates on a full @cra_blocksize and it is not possible
229  *		 to encrypt a block of smaller size. The supplied buffers must
230  *		 therefore also be at least of @cra_blocksize size. Both the
231  *		 input and output buffers are always aligned to @cra_alignmask.
232  *		 In case either of the input or output buffer supplied by user
233  *		 of the crypto API is not aligned to @cra_alignmask, the crypto
234  *		 API will re-align the buffers. The re-alignment means that a
235  *		 new buffer will be allocated, the data will be copied into the
236  *		 new buffer, then the processing will happen on the new buffer,
237  *		 then the data will be copied back into the original buffer and
238  *		 finally the new buffer will be freed. In case a software
239  *		 fallback was put in place in the @cra_init call, this function
240  *		 might need to use the fallback if the algorithm doesn't support
241  *		 all of the key sizes. In case the key was stored in
242  *		 transformation context, the key might need to be re-programmed
243  *		 into the hardware in this function. This function shall not
244  *		 modify the transformation context, as this function may be
245  *		 called in parallel with the same transformation object.
246  * @cia_decrypt: Decrypt a single block. This is a reverse counterpart to
247  *		 @cia_encrypt, and the conditions are exactly the same.
248  *
249  * All fields are mandatory and must be filled.
250  */
251 struct cipher_alg {
252 	unsigned int cia_min_keysize;
253 	unsigned int cia_max_keysize;
254 	int (*cia_setkey)(struct crypto_tfm *tfm, const u8 *key,
255 	                  unsigned int keylen);
256 	void (*cia_encrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
257 	void (*cia_decrypt)(struct crypto_tfm *tfm, u8 *dst, const u8 *src);
258 };
259 
260 /**
261  * struct compress_alg - compression/decompression algorithm
262  * @coa_compress: Compress a buffer of specified length, storing the resulting
263  *		  data in the specified buffer. Return the length of the
264  *		  compressed data in dlen.
265  * @coa_decompress: Decompress the source buffer, storing the uncompressed
266  *		    data in the specified buffer. The length of the data is
267  *		    returned in dlen.
268  *
269  * All fields are mandatory.
270  */
271 struct compress_alg {
272 	int (*coa_compress)(struct crypto_tfm *tfm, const u8 *src,
273 			    unsigned int slen, u8 *dst, unsigned int *dlen);
274 	int (*coa_decompress)(struct crypto_tfm *tfm, const u8 *src,
275 			      unsigned int slen, u8 *dst, unsigned int *dlen);
276 };
277 
278 #ifdef CONFIG_CRYPTO_STATS
279 /*
280  * struct crypto_istat_cipher - statistics for cipher algorithm
281  * @encrypt_cnt:	number of encrypt requests
282  * @encrypt_tlen:	total data size handled by encrypt requests
283  * @decrypt_cnt:	number of decrypt requests
284  * @decrypt_tlen:	total data size handled by decrypt requests
285  * @err_cnt:		number of error for cipher requests
286  */
287 struct crypto_istat_cipher {
288 	atomic64_t encrypt_cnt;
289 	atomic64_t encrypt_tlen;
290 	atomic64_t decrypt_cnt;
291 	atomic64_t decrypt_tlen;
292 	atomic64_t err_cnt;
293 };
294 
295 /*
296  * struct crypto_istat_rng: statistics for RNG algorithm
297  * @generate_cnt:	number of RNG generate requests
298  * @generate_tlen:	total data size of generated data by the RNG
299  * @seed_cnt:		number of times the RNG was seeded
300  * @err_cnt:		number of error for RNG requests
301  */
302 struct crypto_istat_rng {
303 	atomic64_t generate_cnt;
304 	atomic64_t generate_tlen;
305 	atomic64_t seed_cnt;
306 	atomic64_t err_cnt;
307 };
308 #endif /* CONFIG_CRYPTO_STATS */
309 
310 #define cra_cipher	cra_u.cipher
311 #define cra_compress	cra_u.compress
312 
313 /**
314  * struct crypto_alg - definition of a cryptograpic cipher algorithm
315  * @cra_flags: Flags describing this transformation. See include/linux/crypto.h
316  *	       CRYPTO_ALG_* flags for the flags which go in here. Those are
317  *	       used for fine-tuning the description of the transformation
318  *	       algorithm.
319  * @cra_blocksize: Minimum block size of this transformation. The size in bytes
320  *		   of the smallest possible unit which can be transformed with
321  *		   this algorithm. The users must respect this value.
322  *		   In case of HASH transformation, it is possible for a smaller
323  *		   block than @cra_blocksize to be passed to the crypto API for
324  *		   transformation, in case of any other transformation type, an
325  * 		   error will be returned upon any attempt to transform smaller
326  *		   than @cra_blocksize chunks.
327  * @cra_ctxsize: Size of the operational context of the transformation. This
328  *		 value informs the kernel crypto API about the memory size
329  *		 needed to be allocated for the transformation context.
330  * @cra_alignmask: Alignment mask for the input and output data buffer. The data
331  *		   buffer containing the input data for the algorithm must be
332  *		   aligned to this alignment mask. The data buffer for the
333  *		   output data must be aligned to this alignment mask. Note that
334  *		   the Crypto API will do the re-alignment in software, but
335  *		   only under special conditions and there is a performance hit.
336  *		   The re-alignment happens at these occasions for different
337  *		   @cra_u types: cipher -- For both input data and output data
338  *		   buffer; ahash -- For output hash destination buf; shash --
339  *		   For output hash destination buf.
340  *		   This is needed on hardware which is flawed by design and
341  *		   cannot pick data from arbitrary addresses.
342  * @cra_priority: Priority of this transformation implementation. In case
343  *		  multiple transformations with same @cra_name are available to
344  *		  the Crypto API, the kernel will use the one with highest
345  *		  @cra_priority.
346  * @cra_name: Generic name (usable by multiple implementations) of the
347  *	      transformation algorithm. This is the name of the transformation
348  *	      itself. This field is used by the kernel when looking up the
349  *	      providers of particular transformation.
350  * @cra_driver_name: Unique name of the transformation provider. This is the
351  *		     name of the provider of the transformation. This can be any
352  *		     arbitrary value, but in the usual case, this contains the
353  *		     name of the chip or provider and the name of the
354  *		     transformation algorithm.
355  * @cra_type: Type of the cryptographic transformation. This is a pointer to
356  *	      struct crypto_type, which implements callbacks common for all
357  *	      transformation types. There are multiple options, such as
358  *	      &crypto_skcipher_type, &crypto_ahash_type, &crypto_rng_type.
359  *	      This field might be empty. In that case, there are no common
360  *	      callbacks. This is the case for: cipher, compress, shash.
361  * @cra_u: Callbacks implementing the transformation. This is a union of
362  *	   multiple structures. Depending on the type of transformation selected
363  *	   by @cra_type and @cra_flags above, the associated structure must be
364  *	   filled with callbacks. This field might be empty. This is the case
365  *	   for ahash, shash.
366  * @cra_init: Initialize the cryptographic transformation object. This function
367  *	      is used to initialize the cryptographic transformation object.
368  *	      This function is called only once at the instantiation time, right
369  *	      after the transformation context was allocated. In case the
370  *	      cryptographic hardware has some special requirements which need to
371  *	      be handled by software, this function shall check for the precise
372  *	      requirement of the transformation and put any software fallbacks
373  *	      in place.
374  * @cra_exit: Deinitialize the cryptographic transformation object. This is a
375  *	      counterpart to @cra_init, used to remove various changes set in
376  *	      @cra_init.
377  * @cra_u.cipher: Union member which contains a single-block symmetric cipher
378  *		  definition. See @struct @cipher_alg.
379  * @cra_u.compress: Union member which contains a (de)compression algorithm.
380  *		    See @struct @compress_alg.
381  * @cra_module: Owner of this transformation implementation. Set to THIS_MODULE
382  * @cra_list: internally used
383  * @cra_users: internally used
384  * @cra_refcnt: internally used
385  * @cra_destroy: internally used
386  *
387  * @stats: union of all possible crypto_istat_xxx structures
388  * @stats.cipher:	statistics for cipher algorithm
389  * @stats.rng:		statistics for rng algorithm
390  *
391  * The struct crypto_alg describes a generic Crypto API algorithm and is common
392  * for all of the transformations. Any variable not documented here shall not
393  * be used by a cipher implementation as it is internal to the Crypto API.
394  */
395 struct crypto_alg {
396 	struct list_head cra_list;
397 	struct list_head cra_users;
398 
399 	u32 cra_flags;
400 	unsigned int cra_blocksize;
401 	unsigned int cra_ctxsize;
402 	unsigned int cra_alignmask;
403 
404 	int cra_priority;
405 	refcount_t cra_refcnt;
406 
407 	char cra_name[CRYPTO_MAX_ALG_NAME];
408 	char cra_driver_name[CRYPTO_MAX_ALG_NAME];
409 
410 	const struct crypto_type *cra_type;
411 
412 	union {
413 		struct cipher_alg cipher;
414 		struct compress_alg compress;
415 	} cra_u;
416 
417 	int (*cra_init)(struct crypto_tfm *tfm);
418 	void (*cra_exit)(struct crypto_tfm *tfm);
419 	void (*cra_destroy)(struct crypto_alg *alg);
420 
421 	struct module *cra_module;
422 
423 #ifdef CONFIG_CRYPTO_STATS
424 	union {
425 		struct crypto_istat_cipher cipher;
426 		struct crypto_istat_rng rng;
427 	} stats;
428 #endif /* CONFIG_CRYPTO_STATS */
429 
430 } CRYPTO_MINALIGN_ATTR;
431 
432 #ifdef CONFIG_CRYPTO_STATS
433 void crypto_stats_init(struct crypto_alg *alg);
434 void crypto_stats_get(struct crypto_alg *alg);
435 void crypto_stats_rng_seed(struct crypto_alg *alg, int ret);
436 void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen, int ret);
437 void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret, struct crypto_alg *alg);
438 void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret, struct crypto_alg *alg);
439 #else
440 static inline void crypto_stats_init(struct crypto_alg *alg)
441 {}
442 static inline void crypto_stats_get(struct crypto_alg *alg)
443 {}
444 static inline void crypto_stats_rng_seed(struct crypto_alg *alg, int ret)
445 {}
446 static inline void crypto_stats_rng_generate(struct crypto_alg *alg, unsigned int dlen, int ret)
447 {}
448 static inline void crypto_stats_skcipher_encrypt(unsigned int cryptlen, int ret, struct crypto_alg *alg)
449 {}
450 static inline void crypto_stats_skcipher_decrypt(unsigned int cryptlen, int ret, struct crypto_alg *alg)
451 {}
452 #endif
453 /*
454  * A helper struct for waiting for completion of async crypto ops
455  */
456 struct crypto_wait {
457 	struct completion completion;
458 	int err;
459 };
460 
461 /*
462  * Macro for declaring a crypto op async wait object on stack
463  */
464 #define DECLARE_CRYPTO_WAIT(_wait) \
465 	struct crypto_wait _wait = { \
466 		COMPLETION_INITIALIZER_ONSTACK((_wait).completion), 0 }
467 
468 /*
469  * Async ops completion helper functioons
470  */
471 void crypto_req_done(void *req, int err);
472 
473 static inline int crypto_wait_req(int err, struct crypto_wait *wait)
474 {
475 	switch (err) {
476 	case -EINPROGRESS:
477 	case -EBUSY:
478 		wait_for_completion(&wait->completion);
479 		reinit_completion(&wait->completion);
480 		err = wait->err;
481 		break;
482 	}
483 
484 	return err;
485 }
486 
487 static inline void crypto_init_wait(struct crypto_wait *wait)
488 {
489 	init_completion(&wait->completion);
490 }
491 
492 /*
493  * Algorithm registration interface.
494  */
495 int crypto_register_alg(struct crypto_alg *alg);
496 void crypto_unregister_alg(struct crypto_alg *alg);
497 int crypto_register_algs(struct crypto_alg *algs, int count);
498 void crypto_unregister_algs(struct crypto_alg *algs, int count);
499 
500 /*
501  * Algorithm query interface.
502  */
503 int crypto_has_alg(const char *name, u32 type, u32 mask);
504 
505 /*
506  * Transforms: user-instantiated objects which encapsulate algorithms
507  * and core processing logic.  Managed via crypto_alloc_*() and
508  * crypto_free_*(), as well as the various helpers below.
509  */
510 
511 struct crypto_tfm {
512 
513 	u32 crt_flags;
514 
515 	int node;
516 
517 	void (*exit)(struct crypto_tfm *tfm);
518 
519 	struct crypto_alg *__crt_alg;
520 
521 	void *__crt_ctx[] CRYPTO_MINALIGN_ATTR;
522 };
523 
524 struct crypto_comp {
525 	struct crypto_tfm base;
526 };
527 
528 /*
529  * Transform user interface.
530  */
531 
532 struct crypto_tfm *crypto_alloc_base(const char *alg_name, u32 type, u32 mask);
533 void crypto_destroy_tfm(void *mem, struct crypto_tfm *tfm);
534 
535 static inline void crypto_free_tfm(struct crypto_tfm *tfm)
536 {
537 	return crypto_destroy_tfm(tfm, tfm);
538 }
539 
540 int alg_test(const char *driver, const char *alg, u32 type, u32 mask);
541 
542 /*
543  * Transform helpers which query the underlying algorithm.
544  */
545 static inline const char *crypto_tfm_alg_name(struct crypto_tfm *tfm)
546 {
547 	return tfm->__crt_alg->cra_name;
548 }
549 
550 static inline const char *crypto_tfm_alg_driver_name(struct crypto_tfm *tfm)
551 {
552 	return tfm->__crt_alg->cra_driver_name;
553 }
554 
555 static inline int crypto_tfm_alg_priority(struct crypto_tfm *tfm)
556 {
557 	return tfm->__crt_alg->cra_priority;
558 }
559 
560 static inline u32 crypto_tfm_alg_type(struct crypto_tfm *tfm)
561 {
562 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
563 }
564 
565 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
566 {
567 	return tfm->__crt_alg->cra_blocksize;
568 }
569 
570 static inline unsigned int crypto_tfm_alg_alignmask(struct crypto_tfm *tfm)
571 {
572 	return tfm->__crt_alg->cra_alignmask;
573 }
574 
575 static inline u32 crypto_tfm_get_flags(struct crypto_tfm *tfm)
576 {
577 	return tfm->crt_flags;
578 }
579 
580 static inline void crypto_tfm_set_flags(struct crypto_tfm *tfm, u32 flags)
581 {
582 	tfm->crt_flags |= flags;
583 }
584 
585 static inline void crypto_tfm_clear_flags(struct crypto_tfm *tfm, u32 flags)
586 {
587 	tfm->crt_flags &= ~flags;
588 }
589 
590 static inline unsigned int crypto_tfm_ctx_alignment(void)
591 {
592 	struct crypto_tfm *tfm;
593 	return __alignof__(tfm->__crt_ctx);
594 }
595 
596 static inline struct crypto_comp *__crypto_comp_cast(struct crypto_tfm *tfm)
597 {
598 	return (struct crypto_comp *)tfm;
599 }
600 
601 static inline struct crypto_comp *crypto_alloc_comp(const char *alg_name,
602 						    u32 type, u32 mask)
603 {
604 	type &= ~CRYPTO_ALG_TYPE_MASK;
605 	type |= CRYPTO_ALG_TYPE_COMPRESS;
606 	mask |= CRYPTO_ALG_TYPE_MASK;
607 
608 	return __crypto_comp_cast(crypto_alloc_base(alg_name, type, mask));
609 }
610 
611 static inline struct crypto_tfm *crypto_comp_tfm(struct crypto_comp *tfm)
612 {
613 	return &tfm->base;
614 }
615 
616 static inline void crypto_free_comp(struct crypto_comp *tfm)
617 {
618 	crypto_free_tfm(crypto_comp_tfm(tfm));
619 }
620 
621 static inline int crypto_has_comp(const char *alg_name, u32 type, u32 mask)
622 {
623 	type &= ~CRYPTO_ALG_TYPE_MASK;
624 	type |= CRYPTO_ALG_TYPE_COMPRESS;
625 	mask |= CRYPTO_ALG_TYPE_MASK;
626 
627 	return crypto_has_alg(alg_name, type, mask);
628 }
629 
630 static inline const char *crypto_comp_name(struct crypto_comp *tfm)
631 {
632 	return crypto_tfm_alg_name(crypto_comp_tfm(tfm));
633 }
634 
635 int crypto_comp_compress(struct crypto_comp *tfm,
636 			 const u8 *src, unsigned int slen,
637 			 u8 *dst, unsigned int *dlen);
638 
639 int crypto_comp_decompress(struct crypto_comp *tfm,
640 			   const u8 *src, unsigned int slen,
641 			   u8 *dst, unsigned int *dlen);
642 
643 #endif	/* _LINUX_CRYPTO_H */
644 
645