Commit | Line | Data |
---|---|---|
61da88e2 HX |
1 | /* |
2 | * Symmetric key ciphers. | |
3 | * | |
7a7ffe65 | 4 | * Copyright (c) 2007-2015 Herbert Xu <herbert@gondor.apana.org.au> |
61da88e2 HX |
5 | * |
6 | * This program is free software; you can redistribute it and/or modify it | |
7 | * under the terms of the GNU General Public License as published by the Free | |
8 | * Software Foundation; either version 2 of the License, or (at your option) | |
9 | * any later version. | |
10 | * | |
11 | */ | |
12 | ||
13 | #ifndef _CRYPTO_SKCIPHER_H | |
14 | #define _CRYPTO_SKCIPHER_H | |
15 | ||
16 | #include <linux/crypto.h> | |
03bf712f HX |
17 | #include <linux/kernel.h> |
18 | #include <linux/slab.h> | |
61da88e2 | 19 | |
7a7ffe65 HX |
20 | /** |
21 | * struct skcipher_request - Symmetric key cipher request | |
22 | * @cryptlen: Number of bytes to encrypt or decrypt | |
23 | * @iv: Initialisation Vector | |
24 | * @src: Source SG list | |
25 | * @dst: Destination SG list | |
26 | * @base: Underlying async request request | |
27 | * @__ctx: Start of private context data | |
28 | */ | |
29 | struct skcipher_request { | |
30 | unsigned int cryptlen; | |
31 | ||
32 | u8 *iv; | |
33 | ||
34 | struct scatterlist *src; | |
35 | struct scatterlist *dst; | |
36 | ||
37 | struct crypto_async_request base; | |
38 | ||
39 | void *__ctx[] CRYPTO_MINALIGN_ATTR; | |
40 | }; | |
41 | ||
61da88e2 HX |
42 | /** |
43 | * struct skcipher_givcrypt_request - Crypto request with IV generation | |
44 | * @seq: Sequence number for IV generation | |
45 | * @giv: Space for generated IV | |
46 | * @creq: The crypto request itself | |
47 | */ | |
48 | struct skcipher_givcrypt_request { | |
49 | u64 seq; | |
50 | u8 *giv; | |
51 | ||
52 | struct ablkcipher_request creq; | |
53 | }; | |
54 | ||
7a7ffe65 HX |
55 | struct crypto_skcipher { |
56 | int (*setkey)(struct crypto_skcipher *tfm, const u8 *key, | |
57 | unsigned int keylen); | |
58 | int (*encrypt)(struct skcipher_request *req); | |
59 | int (*decrypt)(struct skcipher_request *req); | |
60 | ||
61 | unsigned int ivsize; | |
62 | unsigned int reqsize; | |
63 | ||
a1383cd8 HX |
64 | bool has_setkey; |
65 | ||
7a7ffe65 HX |
66 | struct crypto_tfm base; |
67 | }; | |
68 | ||
69 | #define SKCIPHER_REQUEST_ON_STACK(name, tfm) \ | |
70 | char __##name##_desc[sizeof(struct skcipher_request) + \ | |
71 | crypto_skcipher_reqsize(tfm)] CRYPTO_MINALIGN_ATTR; \ | |
72 | struct skcipher_request *name = (void *)__##name##_desc | |
73 | ||
61da88e2 HX |
74 | static inline struct crypto_ablkcipher *skcipher_givcrypt_reqtfm( |
75 | struct skcipher_givcrypt_request *req) | |
76 | { | |
77 | return crypto_ablkcipher_reqtfm(&req->creq); | |
78 | } | |
79 | ||
03bf712f HX |
80 | static inline int crypto_skcipher_givencrypt( |
81 | struct skcipher_givcrypt_request *req) | |
82 | { | |
83 | struct ablkcipher_tfm *crt = | |
84 | crypto_ablkcipher_crt(skcipher_givcrypt_reqtfm(req)); | |
85 | return crt->givencrypt(req); | |
86 | }; | |
87 | ||
88 | static inline int crypto_skcipher_givdecrypt( | |
89 | struct skcipher_givcrypt_request *req) | |
90 | { | |
91 | struct ablkcipher_tfm *crt = | |
92 | crypto_ablkcipher_crt(skcipher_givcrypt_reqtfm(req)); | |
93 | return crt->givdecrypt(req); | |
94 | }; | |
95 | ||
96 | static inline void skcipher_givcrypt_set_tfm( | |
97 | struct skcipher_givcrypt_request *req, struct crypto_ablkcipher *tfm) | |
98 | { | |
99 | req->creq.base.tfm = crypto_ablkcipher_tfm(tfm); | |
100 | } | |
101 | ||
102 | static inline struct skcipher_givcrypt_request *skcipher_givcrypt_cast( | |
103 | struct crypto_async_request *req) | |
104 | { | |
105 | return container_of(ablkcipher_request_cast(req), | |
106 | struct skcipher_givcrypt_request, creq); | |
107 | } | |
108 | ||
109 | static inline struct skcipher_givcrypt_request *skcipher_givcrypt_alloc( | |
110 | struct crypto_ablkcipher *tfm, gfp_t gfp) | |
111 | { | |
112 | struct skcipher_givcrypt_request *req; | |
113 | ||
114 | req = kmalloc(sizeof(struct skcipher_givcrypt_request) + | |
115 | crypto_ablkcipher_reqsize(tfm), gfp); | |
116 | ||
117 | if (likely(req)) | |
118 | skcipher_givcrypt_set_tfm(req, tfm); | |
119 | ||
120 | return req; | |
121 | } | |
122 | ||
123 | static inline void skcipher_givcrypt_free(struct skcipher_givcrypt_request *req) | |
124 | { | |
125 | kfree(req); | |
126 | } | |
127 | ||
128 | static inline void skcipher_givcrypt_set_callback( | |
129 | struct skcipher_givcrypt_request *req, u32 flags, | |
3e3dc25f | 130 | crypto_completion_t compl, void *data) |
03bf712f | 131 | { |
3e3dc25f | 132 | ablkcipher_request_set_callback(&req->creq, flags, compl, data); |
03bf712f HX |
133 | } |
134 | ||
135 | static inline void skcipher_givcrypt_set_crypt( | |
136 | struct skcipher_givcrypt_request *req, | |
137 | struct scatterlist *src, struct scatterlist *dst, | |
138 | unsigned int nbytes, void *iv) | |
139 | { | |
140 | ablkcipher_request_set_crypt(&req->creq, src, dst, nbytes, iv); | |
141 | } | |
142 | ||
143 | static inline void skcipher_givcrypt_set_giv( | |
144 | struct skcipher_givcrypt_request *req, u8 *giv, u64 seq) | |
145 | { | |
146 | req->giv = giv; | |
147 | req->seq = seq; | |
148 | } | |
149 | ||
7a7ffe65 HX |
150 | /** |
151 | * DOC: Symmetric Key Cipher API | |
152 | * | |
153 | * Symmetric key cipher API is used with the ciphers of type | |
154 | * CRYPTO_ALG_TYPE_SKCIPHER (listed as type "skcipher" in /proc/crypto). | |
155 | * | |
156 | * Asynchronous cipher operations imply that the function invocation for a | |
157 | * cipher request returns immediately before the completion of the operation. | |
158 | * The cipher request is scheduled as a separate kernel thread and therefore | |
159 | * load-balanced on the different CPUs via the process scheduler. To allow | |
160 | * the kernel crypto API to inform the caller about the completion of a cipher | |
161 | * request, the caller must provide a callback function. That function is | |
162 | * invoked with the cipher handle when the request completes. | |
163 | * | |
164 | * To support the asynchronous operation, additional information than just the | |
165 | * cipher handle must be supplied to the kernel crypto API. That additional | |
166 | * information is given by filling in the skcipher_request data structure. | |
167 | * | |
168 | * For the symmetric key cipher API, the state is maintained with the tfm | |
169 | * cipher handle. A single tfm can be used across multiple calls and in | |
170 | * parallel. For asynchronous block cipher calls, context data supplied and | |
171 | * only used by the caller can be referenced the request data structure in | |
172 | * addition to the IV used for the cipher request. The maintenance of such | |
173 | * state information would be important for a crypto driver implementer to | |
174 | * have, because when calling the callback function upon completion of the | |
175 | * cipher operation, that callback function may need some information about | |
176 | * which operation just finished if it invoked multiple in parallel. This | |
177 | * state information is unused by the kernel crypto API. | |
178 | */ | |
179 | ||
180 | static inline struct crypto_skcipher *__crypto_skcipher_cast( | |
181 | struct crypto_tfm *tfm) | |
182 | { | |
183 | return container_of(tfm, struct crypto_skcipher, base); | |
184 | } | |
185 | ||
186 | /** | |
187 | * crypto_alloc_skcipher() - allocate symmetric key cipher handle | |
188 | * @alg_name: is the cra_name / name or cra_driver_name / driver name of the | |
189 | * skcipher cipher | |
190 | * @type: specifies the type of the cipher | |
191 | * @mask: specifies the mask for the cipher | |
192 | * | |
193 | * Allocate a cipher handle for an skcipher. The returned struct | |
194 | * crypto_skcipher is the cipher handle that is required for any subsequent | |
195 | * API invocation for that skcipher. | |
196 | * | |
197 | * Return: allocated cipher handle in case of success; IS_ERR() is true in case | |
198 | * of an error, PTR_ERR() returns the error code. | |
199 | */ | |
200 | struct crypto_skcipher *crypto_alloc_skcipher(const char *alg_name, | |
201 | u32 type, u32 mask); | |
202 | ||
203 | static inline struct crypto_tfm *crypto_skcipher_tfm( | |
204 | struct crypto_skcipher *tfm) | |
205 | { | |
206 | return &tfm->base; | |
207 | } | |
208 | ||
209 | /** | |
210 | * crypto_free_skcipher() - zeroize and free cipher handle | |
211 | * @tfm: cipher handle to be freed | |
212 | */ | |
213 | static inline void crypto_free_skcipher(struct crypto_skcipher *tfm) | |
214 | { | |
215 | crypto_destroy_tfm(tfm, crypto_skcipher_tfm(tfm)); | |
216 | } | |
217 | ||
218 | /** | |
219 | * crypto_has_skcipher() - Search for the availability of an skcipher. | |
220 | * @alg_name: is the cra_name / name or cra_driver_name / driver name of the | |
221 | * skcipher | |
222 | * @type: specifies the type of the cipher | |
223 | * @mask: specifies the mask for the cipher | |
224 | * | |
225 | * Return: true when the skcipher is known to the kernel crypto API; false | |
226 | * otherwise | |
227 | */ | |
228 | static inline int crypto_has_skcipher(const char *alg_name, u32 type, | |
229 | u32 mask) | |
230 | { | |
231 | return crypto_has_alg(alg_name, crypto_skcipher_type(type), | |
232 | crypto_skcipher_mask(mask)); | |
233 | } | |
234 | ||
235 | /** | |
236 | * crypto_skcipher_ivsize() - obtain IV size | |
237 | * @tfm: cipher handle | |
238 | * | |
239 | * The size of the IV for the skcipher referenced by the cipher handle is | |
240 | * returned. This IV size may be zero if the cipher does not need an IV. | |
241 | * | |
242 | * Return: IV size in bytes | |
243 | */ | |
244 | static inline unsigned int crypto_skcipher_ivsize(struct crypto_skcipher *tfm) | |
245 | { | |
246 | return tfm->ivsize; | |
247 | } | |
248 | ||
249 | /** | |
250 | * crypto_skcipher_blocksize() - obtain block size of cipher | |
251 | * @tfm: cipher handle | |
252 | * | |
253 | * The block size for the skcipher referenced with the cipher handle is | |
254 | * returned. The caller may use that information to allocate appropriate | |
255 | * memory for the data returned by the encryption or decryption operation | |
256 | * | |
257 | * Return: block size of cipher | |
258 | */ | |
259 | static inline unsigned int crypto_skcipher_blocksize( | |
260 | struct crypto_skcipher *tfm) | |
261 | { | |
262 | return crypto_tfm_alg_blocksize(crypto_skcipher_tfm(tfm)); | |
263 | } | |
264 | ||
265 | static inline unsigned int crypto_skcipher_alignmask( | |
266 | struct crypto_skcipher *tfm) | |
267 | { | |
268 | return crypto_tfm_alg_alignmask(crypto_skcipher_tfm(tfm)); | |
269 | } | |
270 | ||
271 | static inline u32 crypto_skcipher_get_flags(struct crypto_skcipher *tfm) | |
272 | { | |
273 | return crypto_tfm_get_flags(crypto_skcipher_tfm(tfm)); | |
274 | } | |
275 | ||
276 | static inline void crypto_skcipher_set_flags(struct crypto_skcipher *tfm, | |
277 | u32 flags) | |
278 | { | |
279 | crypto_tfm_set_flags(crypto_skcipher_tfm(tfm), flags); | |
280 | } | |
281 | ||
282 | static inline void crypto_skcipher_clear_flags(struct crypto_skcipher *tfm, | |
283 | u32 flags) | |
284 | { | |
285 | crypto_tfm_clear_flags(crypto_skcipher_tfm(tfm), flags); | |
286 | } | |
287 | ||
288 | /** | |
289 | * crypto_skcipher_setkey() - set key for cipher | |
290 | * @tfm: cipher handle | |
291 | * @key: buffer holding the key | |
292 | * @keylen: length of the key in bytes | |
293 | * | |
294 | * The caller provided key is set for the skcipher referenced by the cipher | |
295 | * handle. | |
296 | * | |
297 | * Note, the key length determines the cipher type. Many block ciphers implement | |
298 | * different cipher modes depending on the key size, such as AES-128 vs AES-192 | |
299 | * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128 | |
300 | * is performed. | |
301 | * | |
302 | * Return: 0 if the setting of the key was successful; < 0 if an error occurred | |
303 | */ | |
304 | static inline int crypto_skcipher_setkey(struct crypto_skcipher *tfm, | |
305 | const u8 *key, unsigned int keylen) | |
306 | { | |
307 | return tfm->setkey(tfm, key, keylen); | |
308 | } | |
309 | ||
a1383cd8 HX |
310 | static inline bool crypto_skcipher_has_setkey(struct crypto_skcipher *tfm) |
311 | { | |
312 | return tfm->has_setkey; | |
313 | } | |
314 | ||
7a7ffe65 HX |
315 | /** |
316 | * crypto_skcipher_reqtfm() - obtain cipher handle from request | |
317 | * @req: skcipher_request out of which the cipher handle is to be obtained | |
318 | * | |
319 | * Return the crypto_skcipher handle when furnishing an skcipher_request | |
320 | * data structure. | |
321 | * | |
322 | * Return: crypto_skcipher handle | |
323 | */ | |
324 | static inline struct crypto_skcipher *crypto_skcipher_reqtfm( | |
325 | struct skcipher_request *req) | |
326 | { | |
327 | return __crypto_skcipher_cast(req->base.tfm); | |
328 | } | |
329 | ||
330 | /** | |
331 | * crypto_skcipher_encrypt() - encrypt plaintext | |
332 | * @req: reference to the skcipher_request handle that holds all information | |
333 | * needed to perform the cipher operation | |
334 | * | |
335 | * Encrypt plaintext data using the skcipher_request handle. That data | |
336 | * structure and how it is filled with data is discussed with the | |
337 | * skcipher_request_* functions. | |
338 | * | |
339 | * Return: 0 if the cipher operation was successful; < 0 if an error occurred | |
340 | */ | |
341 | static inline int crypto_skcipher_encrypt(struct skcipher_request *req) | |
342 | { | |
343 | struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); | |
344 | ||
345 | return tfm->encrypt(req); | |
346 | } | |
347 | ||
348 | /** | |
349 | * crypto_skcipher_decrypt() - decrypt ciphertext | |
350 | * @req: reference to the skcipher_request handle that holds all information | |
351 | * needed to perform the cipher operation | |
352 | * | |
353 | * Decrypt ciphertext data using the skcipher_request handle. That data | |
354 | * structure and how it is filled with data is discussed with the | |
355 | * skcipher_request_* functions. | |
356 | * | |
357 | * Return: 0 if the cipher operation was successful; < 0 if an error occurred | |
358 | */ | |
359 | static inline int crypto_skcipher_decrypt(struct skcipher_request *req) | |
360 | { | |
361 | struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); | |
362 | ||
363 | return tfm->decrypt(req); | |
364 | } | |
365 | ||
366 | /** | |
367 | * DOC: Symmetric Key Cipher Request Handle | |
368 | * | |
369 | * The skcipher_request data structure contains all pointers to data | |
370 | * required for the symmetric key cipher operation. This includes the cipher | |
371 | * handle (which can be used by multiple skcipher_request instances), pointer | |
372 | * to plaintext and ciphertext, asynchronous callback function, etc. It acts | |
373 | * as a handle to the skcipher_request_* API calls in a similar way as | |
374 | * skcipher handle to the crypto_skcipher_* API calls. | |
375 | */ | |
376 | ||
377 | /** | |
378 | * crypto_skcipher_reqsize() - obtain size of the request data structure | |
379 | * @tfm: cipher handle | |
380 | * | |
381 | * Return: number of bytes | |
382 | */ | |
383 | static inline unsigned int crypto_skcipher_reqsize(struct crypto_skcipher *tfm) | |
384 | { | |
385 | return tfm->reqsize; | |
386 | } | |
387 | ||
388 | /** | |
389 | * skcipher_request_set_tfm() - update cipher handle reference in request | |
390 | * @req: request handle to be modified | |
391 | * @tfm: cipher handle that shall be added to the request handle | |
392 | * | |
393 | * Allow the caller to replace the existing skcipher handle in the request | |
394 | * data structure with a different one. | |
395 | */ | |
396 | static inline void skcipher_request_set_tfm(struct skcipher_request *req, | |
397 | struct crypto_skcipher *tfm) | |
398 | { | |
399 | req->base.tfm = crypto_skcipher_tfm(tfm); | |
400 | } | |
401 | ||
402 | static inline struct skcipher_request *skcipher_request_cast( | |
403 | struct crypto_async_request *req) | |
404 | { | |
405 | return container_of(req, struct skcipher_request, base); | |
406 | } | |
407 | ||
408 | /** | |
409 | * skcipher_request_alloc() - allocate request data structure | |
410 | * @tfm: cipher handle to be registered with the request | |
411 | * @gfp: memory allocation flag that is handed to kmalloc by the API call. | |
412 | * | |
413 | * Allocate the request data structure that must be used with the skcipher | |
414 | * encrypt and decrypt API calls. During the allocation, the provided skcipher | |
415 | * handle is registered in the request data structure. | |
416 | * | |
417 | * Return: allocated request handle in case of success; IS_ERR() is true in case | |
418 | * of an error, PTR_ERR() returns the error code. | |
419 | */ | |
420 | static inline struct skcipher_request *skcipher_request_alloc( | |
421 | struct crypto_skcipher *tfm, gfp_t gfp) | |
422 | { | |
423 | struct skcipher_request *req; | |
424 | ||
425 | req = kmalloc(sizeof(struct skcipher_request) + | |
426 | crypto_skcipher_reqsize(tfm), gfp); | |
427 | ||
428 | if (likely(req)) | |
429 | skcipher_request_set_tfm(req, tfm); | |
430 | ||
431 | return req; | |
432 | } | |
433 | ||
434 | /** | |
435 | * skcipher_request_free() - zeroize and free request data structure | |
436 | * @req: request data structure cipher handle to be freed | |
437 | */ | |
438 | static inline void skcipher_request_free(struct skcipher_request *req) | |
439 | { | |
440 | kzfree(req); | |
441 | } | |
442 | ||
443 | /** | |
444 | * skcipher_request_set_callback() - set asynchronous callback function | |
445 | * @req: request handle | |
446 | * @flags: specify zero or an ORing of the flags | |
447 | * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and | |
448 | * increase the wait queue beyond the initial maximum size; | |
449 | * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep | |
450 | * @compl: callback function pointer to be registered with the request handle | |
451 | * @data: The data pointer refers to memory that is not used by the kernel | |
452 | * crypto API, but provided to the callback function for it to use. Here, | |
453 | * the caller can provide a reference to memory the callback function can | |
454 | * operate on. As the callback function is invoked asynchronously to the | |
455 | * related functionality, it may need to access data structures of the | |
456 | * related functionality which can be referenced using this pointer. The | |
457 | * callback function can access the memory via the "data" field in the | |
458 | * crypto_async_request data structure provided to the callback function. | |
459 | * | |
460 | * This function allows setting the callback function that is triggered once the | |
461 | * cipher operation completes. | |
462 | * | |
463 | * The callback function is registered with the skcipher_request handle and | |
464 | * must comply with the following template | |
465 | * | |
466 | * void callback_function(struct crypto_async_request *req, int error) | |
467 | */ | |
468 | static inline void skcipher_request_set_callback(struct skcipher_request *req, | |
469 | u32 flags, | |
470 | crypto_completion_t compl, | |
471 | void *data) | |
472 | { | |
473 | req->base.complete = compl; | |
474 | req->base.data = data; | |
475 | req->base.flags = flags; | |
476 | } | |
477 | ||
478 | /** | |
479 | * skcipher_request_set_crypt() - set data buffers | |
480 | * @req: request handle | |
481 | * @src: source scatter / gather list | |
482 | * @dst: destination scatter / gather list | |
483 | * @cryptlen: number of bytes to process from @src | |
484 | * @iv: IV for the cipher operation which must comply with the IV size defined | |
485 | * by crypto_skcipher_ivsize | |
486 | * | |
487 | * This function allows setting of the source data and destination data | |
488 | * scatter / gather lists. | |
489 | * | |
490 | * For encryption, the source is treated as the plaintext and the | |
491 | * destination is the ciphertext. For a decryption operation, the use is | |
492 | * reversed - the source is the ciphertext and the destination is the plaintext. | |
493 | */ | |
494 | static inline void skcipher_request_set_crypt( | |
495 | struct skcipher_request *req, | |
496 | struct scatterlist *src, struct scatterlist *dst, | |
497 | unsigned int cryptlen, void *iv) | |
498 | { | |
499 | req->src = src; | |
500 | req->dst = dst; | |
501 | req->cryptlen = cryptlen; | |
502 | req->iv = iv; | |
503 | } | |
504 | ||
61da88e2 HX |
505 | #endif /* _CRYPTO_SKCIPHER_H */ |
506 |