1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * Hash: Hash algorithms under the crypto API 4 * 5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> 6 */ 7 8 #ifndef _CRYPTO_HASH_H 9 #define _CRYPTO_HASH_H 10 11 #include <linux/atomic.h> 12 #include <linux/crypto.h> 13 #include <linux/string.h> 14 15 struct crypto_ahash; 16 17 /** 18 * DOC: Message Digest Algorithm Definitions 19 * 20 * These data structures define modular message digest algorithm 21 * implementations, managed via crypto_register_ahash(), 22 * crypto_register_shash(), crypto_unregister_ahash() and 23 * crypto_unregister_shash(). 24 */ 25 26 /* 27 * struct hash_alg_common - define properties of message digest 28 * @digestsize: Size of the result of the transformation. A buffer of this size 29 * must be available to the @final and @finup calls, so they can 30 * store the resulting hash into it. For various predefined sizes, 31 * search include/crypto/ using 32 * git grep _DIGEST_SIZE include/crypto. 33 * @statesize: Size of the block for partial state of the transformation. A 34 * buffer of this size must be passed to the @export function as it 35 * will save the partial state of the transformation into it. On the 36 * other side, the @import function will load the state from a 37 * buffer of this size as well. 38 * @base: Start of data structure of cipher algorithm. The common data 39 * structure of crypto_alg contains information common to all ciphers. 40 * The hash_alg_common data structure now adds the hash-specific 41 * information. 42 */ 43 #define HASH_ALG_COMMON { \ 44 unsigned int digestsize; \ 45 unsigned int statesize; \ 46 \ 47 struct crypto_alg base; \ 48 } 49 struct hash_alg_common HASH_ALG_COMMON; 50 51 struct ahash_request { 52 struct crypto_async_request base; 53 54 unsigned int nbytes; 55 struct scatterlist *src; 56 u8 *result; 57 58 /* This field may only be used by the ahash API code. */ 59 void *priv; 60 61 void *__ctx[] CRYPTO_MINALIGN_ATTR; 62 }; 63 64 /** 65 * struct ahash_alg - asynchronous message digest definition 66 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the 67 * state of the HASH transformation at the beginning. This shall fill in 68 * the internal structures used during the entire duration of the whole 69 * transformation. No data processing happens at this point. Driver code 70 * implementation must not use req->result. 71 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This 72 * function actually pushes blocks of data from upper layers into the 73 * driver, which then passes those to the hardware as seen fit. This 74 * function must not finalize the HASH transformation by calculating the 75 * final message digest as this only adds more data into the 76 * transformation. This function shall not modify the transformation 77 * context, as this function may be called in parallel with the same 78 * transformation object. Data processing can happen synchronously 79 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use 80 * req->result. 81 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the 82 * transformation and retrieves the resulting hash from the driver and 83 * pushes it back to upper layers. No data processing happens at this 84 * point unless hardware requires it to finish the transformation 85 * (then the data buffered by the device driver is processed). 86 * @finup: **[optional]** Combination of @update and @final. This function is effectively a 87 * combination of @update and @final calls issued in sequence. As some 88 * hardware cannot do @update and @final separately, this callback was 89 * added to allow such hardware to be used at least by IPsec. Data 90 * processing can happen synchronously [SHASH] or asynchronously [AHASH] 91 * at this point. 92 * @digest: Combination of @init and @update and @final. This function 93 * effectively behaves as the entire chain of operations, @init, 94 * @update and @final issued in sequence. Just like @finup, this was 95 * added for hardware which cannot do even the @finup, but can only do 96 * the whole transformation in one run. Data processing can happen 97 * synchronously [SHASH] or asynchronously [AHASH] at this point. 98 * @setkey: Set optional key used by the hashing algorithm. Intended to push 99 * optional key used by the hashing algorithm from upper layers into 100 * the driver. This function can store the key in the transformation 101 * context or can outright program it into the hardware. In the former 102 * case, one must be careful to program the key into the hardware at 103 * appropriate time and one must be careful that .setkey() can be 104 * called multiple times during the existence of the transformation 105 * object. Not all hashing algorithms do implement this function as it 106 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT 107 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement 108 * this function. This function must be called before any other of the 109 * @init, @update, @final, @finup, @digest is called. No data 110 * processing happens at this point. 111 * @export: Export partial state of the transformation. This function dumps the 112 * entire state of the ongoing transformation into a provided block of 113 * data so it can be @import 'ed back later on. This is useful in case 114 * you want to save partial result of the transformation after 115 * processing certain amount of data and reload this partial result 116 * multiple times later on for multiple re-use. No data processing 117 * happens at this point. Driver must not use req->result. 118 * @import: Import partial state of the transformation. This function loads the 119 * entire state of the ongoing transformation from a provided block of 120 * data so the transformation can continue from this point onward. No 121 * data processing happens at this point. Driver must not use 122 * req->result. 123 * @init_tfm: Initialize the cryptographic transformation object. 124 * This function is called only once at the instantiation 125 * time, right after the transformation context was 126 * allocated. In case the cryptographic hardware has 127 * some special requirements which need to be handled 128 * by software, this function shall check for the precise 129 * requirement of the transformation and put any software 130 * fallbacks in place. 131 * @exit_tfm: Deinitialize the cryptographic transformation object. 132 * This is a counterpart to @init_tfm, used to remove 133 * various changes set in @init_tfm. 134 * @clone_tfm: Copy transform into new object, may allocate memory. 135 * @halg: see struct hash_alg_common 136 */ 137 struct ahash_alg { 138 int (*init)(struct ahash_request *req); 139 int (*update)(struct ahash_request *req); 140 int (*final)(struct ahash_request *req); 141 int (*finup)(struct ahash_request *req); 142 int (*digest)(struct ahash_request *req); 143 int (*export)(struct ahash_request *req, void *out); 144 int (*import)(struct ahash_request *req, const void *in); 145 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 146 unsigned int keylen); 147 int (*init_tfm)(struct crypto_ahash *tfm); 148 void (*exit_tfm)(struct crypto_ahash *tfm); 149 int (*clone_tfm)(struct crypto_ahash *dst, struct crypto_ahash *src); 150 151 struct hash_alg_common halg; 152 }; 153 154 struct shash_desc { 155 struct crypto_shash *tfm; 156 void *__ctx[] __aligned(ARCH_SLAB_MINALIGN); 157 }; 158 159 #define HASH_MAX_DIGESTSIZE 64 160 161 /* 162 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' 163 * containing a 'struct sha3_state'. 164 */ 165 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360) 166 167 #define SHASH_DESC_ON_STACK(shash, ctx) \ 168 char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \ 169 __aligned(__alignof__(struct shash_desc)); \ 170 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc 171 172 /** 173 * struct shash_alg - synchronous message digest definition 174 * @init: see struct ahash_alg 175 * @update: see struct ahash_alg 176 * @final: see struct ahash_alg 177 * @finup: see struct ahash_alg 178 * @digest: see struct ahash_alg 179 * @export: see struct ahash_alg 180 * @import: see struct ahash_alg 181 * @setkey: see struct ahash_alg 182 * @init_tfm: Initialize the cryptographic transformation object. 183 * This function is called only once at the instantiation 184 * time, right after the transformation context was 185 * allocated. In case the cryptographic hardware has 186 * some special requirements which need to be handled 187 * by software, this function shall check for the precise 188 * requirement of the transformation and put any software 189 * fallbacks in place. 190 * @exit_tfm: Deinitialize the cryptographic transformation object. 191 * This is a counterpart to @init_tfm, used to remove 192 * various changes set in @init_tfm. 193 * @clone_tfm: Copy transform into new object, may allocate memory. 194 * @descsize: Size of the operational state for the message digest. This state 195 * size is the memory size that needs to be allocated for 196 * shash_desc.__ctx 197 * @halg: see struct hash_alg_common 198 * @HASH_ALG_COMMON: see struct hash_alg_common 199 */ 200 struct shash_alg { 201 int (*init)(struct shash_desc *desc); 202 int (*update)(struct shash_desc *desc, const u8 *data, 203 unsigned int len); 204 int (*final)(struct shash_desc *desc, u8 *out); 205 int (*finup)(struct shash_desc *desc, const u8 *data, 206 unsigned int len, u8 *out); 207 int (*digest)(struct shash_desc *desc, const u8 *data, 208 unsigned int len, u8 *out); 209 int (*export)(struct shash_desc *desc, void *out); 210 int (*import)(struct shash_desc *desc, const void *in); 211 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 212 unsigned int keylen); 213 int (*init_tfm)(struct crypto_shash *tfm); 214 void (*exit_tfm)(struct crypto_shash *tfm); 215 int (*clone_tfm)(struct crypto_shash *dst, struct crypto_shash *src); 216 217 unsigned int descsize; 218 219 union { 220 struct HASH_ALG_COMMON; 221 struct hash_alg_common halg; 222 }; 223 }; 224 #undef HASH_ALG_COMMON 225 226 struct crypto_ahash { 227 bool using_shash; /* Underlying algorithm is shash, not ahash */ 228 unsigned int statesize; 229 unsigned int reqsize; 230 struct crypto_tfm base; 231 }; 232 233 struct crypto_shash { 234 unsigned int descsize; 235 struct crypto_tfm base; 236 }; 237 238 /** 239 * DOC: Asynchronous Message Digest API 240 * 241 * The asynchronous message digest API is used with the ciphers of type 242 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 243 * 244 * The asynchronous cipher operation discussion provided for the 245 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well. 246 */ 247 __crypto_ahash_cast(struct crypto_tfm * tfm)248 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 249 { 250 return container_of(tfm, struct crypto_ahash, base); 251 } 252 253 /** 254 * crypto_alloc_ahash() - allocate ahash cipher handle 255 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 256 * ahash cipher 257 * @type: specifies the type of the cipher 258 * @mask: specifies the mask for the cipher 259 * 260 * Allocate a cipher handle for an ahash. The returned struct 261 * crypto_ahash is the cipher handle that is required for any subsequent 262 * API invocation for that ahash. 263 * 264 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 265 * of an error, PTR_ERR() returns the error code. 266 */ 267 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 268 u32 mask); 269 270 struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *tfm); 271 crypto_ahash_tfm(struct crypto_ahash * tfm)272 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 273 { 274 return &tfm->base; 275 } 276 277 /** 278 * crypto_free_ahash() - zeroize and free the ahash handle 279 * @tfm: cipher handle to be freed 280 * 281 * If @tfm is a NULL or error pointer, this function does nothing. 282 */ crypto_free_ahash(struct crypto_ahash * tfm)283 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 284 { 285 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 286 } 287 288 /** 289 * crypto_has_ahash() - Search for the availability of an ahash. 290 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 291 * ahash 292 * @type: specifies the type of the ahash 293 * @mask: specifies the mask for the ahash 294 * 295 * Return: true when the ahash is known to the kernel crypto API; false 296 * otherwise 297 */ 298 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 299 crypto_ahash_alg_name(struct crypto_ahash * tfm)300 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 301 { 302 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 303 } 304 crypto_ahash_driver_name(struct crypto_ahash * tfm)305 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 306 { 307 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 308 } 309 310 /** 311 * crypto_ahash_blocksize() - obtain block size for cipher 312 * @tfm: cipher handle 313 * 314 * The block size for the message digest cipher referenced with the cipher 315 * handle is returned. 316 * 317 * Return: block size of cipher 318 */ crypto_ahash_blocksize(struct crypto_ahash * tfm)319 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 320 { 321 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 322 } 323 __crypto_hash_alg_common(struct crypto_alg * alg)324 static inline struct hash_alg_common *__crypto_hash_alg_common( 325 struct crypto_alg *alg) 326 { 327 return container_of(alg, struct hash_alg_common, base); 328 } 329 crypto_hash_alg_common(struct crypto_ahash * tfm)330 static inline struct hash_alg_common *crypto_hash_alg_common( 331 struct crypto_ahash *tfm) 332 { 333 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 334 } 335 336 /** 337 * crypto_ahash_digestsize() - obtain message digest size 338 * @tfm: cipher handle 339 * 340 * The size for the message digest created by the message digest cipher 341 * referenced with the cipher handle is returned. 342 * 343 * 344 * Return: message digest size of cipher 345 */ crypto_ahash_digestsize(struct crypto_ahash * tfm)346 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 347 { 348 return crypto_hash_alg_common(tfm)->digestsize; 349 } 350 351 /** 352 * crypto_ahash_statesize() - obtain size of the ahash state 353 * @tfm: cipher handle 354 * 355 * Return the size of the ahash state. With the crypto_ahash_export() 356 * function, the caller can export the state into a buffer whose size is 357 * defined with this function. 358 * 359 * Return: size of the ahash state 360 */ crypto_ahash_statesize(struct crypto_ahash * tfm)361 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 362 { 363 return tfm->statesize; 364 } 365 crypto_ahash_get_flags(struct crypto_ahash * tfm)366 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 367 { 368 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 369 } 370 crypto_ahash_set_flags(struct crypto_ahash * tfm,u32 flags)371 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 372 { 373 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 374 } 375 crypto_ahash_clear_flags(struct crypto_ahash * tfm,u32 flags)376 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 377 { 378 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 379 } 380 381 /** 382 * crypto_ahash_reqtfm() - obtain cipher handle from request 383 * @req: asynchronous request handle that contains the reference to the ahash 384 * cipher handle 385 * 386 * Return the ahash cipher handle that is registered with the asynchronous 387 * request handle ahash_request. 388 * 389 * Return: ahash cipher handle 390 */ crypto_ahash_reqtfm(struct ahash_request * req)391 static inline struct crypto_ahash *crypto_ahash_reqtfm( 392 struct ahash_request *req) 393 { 394 return __crypto_ahash_cast(req->base.tfm); 395 } 396 397 /** 398 * crypto_ahash_reqsize() - obtain size of the request data structure 399 * @tfm: cipher handle 400 * 401 * Return: size of the request data 402 */ crypto_ahash_reqsize(struct crypto_ahash * tfm)403 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 404 { 405 return tfm->reqsize; 406 } 407 ahash_request_ctx(struct ahash_request * req)408 static inline void *ahash_request_ctx(struct ahash_request *req) 409 { 410 return req->__ctx; 411 } 412 413 /** 414 * crypto_ahash_setkey - set key for cipher handle 415 * @tfm: cipher handle 416 * @key: buffer holding the key 417 * @keylen: length of the key in bytes 418 * 419 * The caller provided key is set for the ahash cipher. The cipher 420 * handle must point to a keyed hash in order for this function to succeed. 421 * 422 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 423 */ 424 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 425 unsigned int keylen); 426 427 /** 428 * crypto_ahash_finup() - update and finalize message digest 429 * @req: reference to the ahash_request handle that holds all information 430 * needed to perform the cipher operation 431 * 432 * This function is a "short-hand" for the function calls of 433 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 434 * meaning as discussed for those separate functions. 435 * 436 * Return: see crypto_ahash_final() 437 */ 438 int crypto_ahash_finup(struct ahash_request *req); 439 440 /** 441 * crypto_ahash_final() - calculate message digest 442 * @req: reference to the ahash_request handle that holds all information 443 * needed to perform the cipher operation 444 * 445 * Finalize the message digest operation and create the message digest 446 * based on all data added to the cipher handle. The message digest is placed 447 * into the output buffer registered with the ahash_request handle. 448 * 449 * Return: 450 * 0 if the message digest was successfully calculated; 451 * -EINPROGRESS if data is fed into hardware (DMA) or queued for later; 452 * -EBUSY if queue is full and request should be resubmitted later; 453 * other < 0 if an error occurred 454 */ 455 int crypto_ahash_final(struct ahash_request *req); 456 457 /** 458 * crypto_ahash_digest() - calculate message digest for a buffer 459 * @req: reference to the ahash_request handle that holds all information 460 * needed to perform the cipher operation 461 * 462 * This function is a "short-hand" for the function calls of crypto_ahash_init, 463 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 464 * meaning as discussed for those separate three functions. 465 * 466 * Return: see crypto_ahash_final() 467 */ 468 int crypto_ahash_digest(struct ahash_request *req); 469 470 /** 471 * crypto_ahash_export() - extract current message digest state 472 * @req: reference to the ahash_request handle whose state is exported 473 * @out: output buffer of sufficient size that can hold the hash state 474 * 475 * This function exports the hash state of the ahash_request handle into the 476 * caller-allocated output buffer out which must have sufficient size (e.g. by 477 * calling crypto_ahash_statesize()). 478 * 479 * Return: 0 if the export was successful; < 0 if an error occurred 480 */ 481 int crypto_ahash_export(struct ahash_request *req, void *out); 482 483 /** 484 * crypto_ahash_import() - import message digest state 485 * @req: reference to ahash_request handle the state is imported into 486 * @in: buffer holding the state 487 * 488 * This function imports the hash state into the ahash_request handle from the 489 * input buffer. That buffer should have been generated with the 490 * crypto_ahash_export function. 491 * 492 * Return: 0 if the import was successful; < 0 if an error occurred 493 */ 494 int crypto_ahash_import(struct ahash_request *req, const void *in); 495 496 /** 497 * crypto_ahash_init() - (re)initialize message digest handle 498 * @req: ahash_request handle that already is initialized with all necessary 499 * data using the ahash_request_* API functions 500 * 501 * The call (re-)initializes the message digest referenced by the ahash_request 502 * handle. Any potentially existing state created by previous operations is 503 * discarded. 504 * 505 * Return: see crypto_ahash_final() 506 */ 507 int crypto_ahash_init(struct ahash_request *req); 508 509 /** 510 * crypto_ahash_update() - add data to message digest for processing 511 * @req: ahash_request handle that was previously initialized with the 512 * crypto_ahash_init call. 513 * 514 * Updates the message digest state of the &ahash_request handle. The input data 515 * is pointed to by the scatter/gather list registered in the &ahash_request 516 * handle 517 * 518 * Return: see crypto_ahash_final() 519 */ 520 int crypto_ahash_update(struct ahash_request *req); 521 522 /** 523 * DOC: Asynchronous Hash Request Handle 524 * 525 * The &ahash_request data structure contains all pointers to data 526 * required for the asynchronous cipher operation. This includes the cipher 527 * handle (which can be used by multiple &ahash_request instances), pointer 528 * to plaintext and the message digest output buffer, asynchronous callback 529 * function, etc. It acts as a handle to the ahash_request_* API calls in a 530 * similar way as ahash handle to the crypto_ahash_* API calls. 531 */ 532 533 /** 534 * ahash_request_set_tfm() - update cipher handle reference in request 535 * @req: request handle to be modified 536 * @tfm: cipher handle that shall be added to the request handle 537 * 538 * Allow the caller to replace the existing ahash handle in the request 539 * data structure with a different one. 540 */ ahash_request_set_tfm(struct ahash_request * req,struct crypto_ahash * tfm)541 static inline void ahash_request_set_tfm(struct ahash_request *req, 542 struct crypto_ahash *tfm) 543 { 544 req->base.tfm = crypto_ahash_tfm(tfm); 545 } 546 547 /** 548 * ahash_request_alloc() - allocate request data structure 549 * @tfm: cipher handle to be registered with the request 550 * @gfp: memory allocation flag that is handed to kmalloc by the API call. 551 * 552 * Allocate the request data structure that must be used with the ahash 553 * message digest API calls. During 554 * the allocation, the provided ahash handle 555 * is registered in the request data structure. 556 * 557 * Return: allocated request handle in case of success, or NULL if out of memory 558 */ ahash_request_alloc_noprof(struct crypto_ahash * tfm,gfp_t gfp)559 static inline struct ahash_request *ahash_request_alloc_noprof( 560 struct crypto_ahash *tfm, gfp_t gfp) 561 { 562 struct ahash_request *req; 563 564 req = kmalloc_noprof(sizeof(struct ahash_request) + 565 crypto_ahash_reqsize(tfm), gfp); 566 567 if (likely(req)) 568 ahash_request_set_tfm(req, tfm); 569 570 return req; 571 } 572 #define ahash_request_alloc(...) alloc_hooks(ahash_request_alloc_noprof(__VA_ARGS__)) 573 574 /** 575 * ahash_request_free() - zeroize and free the request data structure 576 * @req: request data structure cipher handle to be freed 577 */ ahash_request_free(struct ahash_request * req)578 static inline void ahash_request_free(struct ahash_request *req) 579 { 580 kfree_sensitive(req); 581 } 582 ahash_request_zero(struct ahash_request * req)583 static inline void ahash_request_zero(struct ahash_request *req) 584 { 585 memzero_explicit(req, sizeof(*req) + 586 crypto_ahash_reqsize(crypto_ahash_reqtfm(req))); 587 } 588 ahash_request_cast(struct crypto_async_request * req)589 static inline struct ahash_request *ahash_request_cast( 590 struct crypto_async_request *req) 591 { 592 return container_of(req, struct ahash_request, base); 593 } 594 595 /** 596 * ahash_request_set_callback() - set asynchronous callback function 597 * @req: request handle 598 * @flags: specify zero or an ORing of the flags 599 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and 600 * increase the wait queue beyond the initial maximum size; 601 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep 602 * @compl: callback function pointer to be registered with the request handle 603 * @data: The data pointer refers to memory that is not used by the kernel 604 * crypto API, but provided to the callback function for it to use. Here, 605 * the caller can provide a reference to memory the callback function can 606 * operate on. As the callback function is invoked asynchronously to the 607 * related functionality, it may need to access data structures of the 608 * related functionality which can be referenced using this pointer. The 609 * callback function can access the memory via the "data" field in the 610 * &crypto_async_request data structure provided to the callback function. 611 * 612 * This function allows setting the callback function that is triggered once 613 * the cipher operation completes. 614 * 615 * The callback function is registered with the &ahash_request handle and 616 * must comply with the following template:: 617 * 618 * void callback_function(struct crypto_async_request *req, int error) 619 */ ahash_request_set_callback(struct ahash_request * req,u32 flags,crypto_completion_t compl,void * data)620 static inline void ahash_request_set_callback(struct ahash_request *req, 621 u32 flags, 622 crypto_completion_t compl, 623 void *data) 624 { 625 req->base.complete = compl; 626 req->base.data = data; 627 req->base.flags = flags; 628 } 629 630 /** 631 * ahash_request_set_crypt() - set data buffers 632 * @req: ahash_request handle to be updated 633 * @src: source scatter/gather list 634 * @result: buffer that is filled with the message digest -- the caller must 635 * ensure that the buffer has sufficient space by, for example, calling 636 * crypto_ahash_digestsize() 637 * @nbytes: number of bytes to process from the source scatter/gather list 638 * 639 * By using this call, the caller references the source scatter/gather list. 640 * The source scatter/gather list points to the data the message digest is to 641 * be calculated for. 642 */ ahash_request_set_crypt(struct ahash_request * req,struct scatterlist * src,u8 * result,unsigned int nbytes)643 static inline void ahash_request_set_crypt(struct ahash_request *req, 644 struct scatterlist *src, u8 *result, 645 unsigned int nbytes) 646 { 647 req->src = src; 648 req->nbytes = nbytes; 649 req->result = result; 650 } 651 652 /** 653 * DOC: Synchronous Message Digest API 654 * 655 * The synchronous message digest API is used with the ciphers of type 656 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) 657 * 658 * The message digest API is able to maintain state information for the 659 * caller. 660 * 661 * The synchronous message digest API can store user-related context in its 662 * shash_desc request data structure. 663 */ 664 665 /** 666 * crypto_alloc_shash() - allocate message digest handle 667 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 668 * message digest cipher 669 * @type: specifies the type of the cipher 670 * @mask: specifies the mask for the cipher 671 * 672 * Allocate a cipher handle for a message digest. The returned &struct 673 * crypto_shash is the cipher handle that is required for any subsequent 674 * API invocation for that message digest. 675 * 676 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 677 * of an error, PTR_ERR() returns the error code. 678 */ 679 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 680 u32 mask); 681 682 struct crypto_shash *crypto_clone_shash(struct crypto_shash *tfm); 683 684 int crypto_has_shash(const char *alg_name, u32 type, u32 mask); 685 crypto_shash_tfm(struct crypto_shash * tfm)686 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 687 { 688 return &tfm->base; 689 } 690 691 /** 692 * crypto_free_shash() - zeroize and free the message digest handle 693 * @tfm: cipher handle to be freed 694 * 695 * If @tfm is a NULL or error pointer, this function does nothing. 696 */ crypto_free_shash(struct crypto_shash * tfm)697 static inline void crypto_free_shash(struct crypto_shash *tfm) 698 { 699 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 700 } 701 crypto_shash_alg_name(struct crypto_shash * tfm)702 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 703 { 704 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 705 } 706 crypto_shash_driver_name(struct crypto_shash * tfm)707 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 708 { 709 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm)); 710 } 711 712 /** 713 * crypto_shash_blocksize() - obtain block size for cipher 714 * @tfm: cipher handle 715 * 716 * The block size for the message digest cipher referenced with the cipher 717 * handle is returned. 718 * 719 * Return: block size of cipher 720 */ crypto_shash_blocksize(struct crypto_shash * tfm)721 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) 722 { 723 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm)); 724 } 725 __crypto_shash_alg(struct crypto_alg * alg)726 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) 727 { 728 return container_of(alg, struct shash_alg, base); 729 } 730 crypto_shash_alg(struct crypto_shash * tfm)731 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) 732 { 733 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg); 734 } 735 736 /** 737 * crypto_shash_digestsize() - obtain message digest size 738 * @tfm: cipher handle 739 * 740 * The size for the message digest created by the message digest cipher 741 * referenced with the cipher handle is returned. 742 * 743 * Return: digest size of cipher 744 */ crypto_shash_digestsize(struct crypto_shash * tfm)745 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) 746 { 747 return crypto_shash_alg(tfm)->digestsize; 748 } 749 crypto_shash_statesize(struct crypto_shash * tfm)750 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) 751 { 752 return crypto_shash_alg(tfm)->statesize; 753 } 754 crypto_shash_get_flags(struct crypto_shash * tfm)755 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) 756 { 757 return crypto_tfm_get_flags(crypto_shash_tfm(tfm)); 758 } 759 crypto_shash_set_flags(struct crypto_shash * tfm,u32 flags)760 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) 761 { 762 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags); 763 } 764 crypto_shash_clear_flags(struct crypto_shash * tfm,u32 flags)765 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) 766 { 767 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags); 768 } 769 770 /** 771 * crypto_shash_descsize() - obtain the operational state size 772 * @tfm: cipher handle 773 * 774 * The size of the operational state the cipher needs during operation is 775 * returned for the hash referenced with the cipher handle. This size is 776 * required to calculate the memory requirements to allow the caller allocating 777 * sufficient memory for operational state. 778 * 779 * The operational state is defined with struct shash_desc where the size of 780 * that data structure is to be calculated as 781 * sizeof(struct shash_desc) + crypto_shash_descsize(alg) 782 * 783 * Return: size of the operational state 784 */ crypto_shash_descsize(struct crypto_shash * tfm)785 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) 786 { 787 return tfm->descsize; 788 } 789 shash_desc_ctx(struct shash_desc * desc)790 static inline void *shash_desc_ctx(struct shash_desc *desc) 791 { 792 return desc->__ctx; 793 } 794 795 /** 796 * crypto_shash_setkey() - set key for message digest 797 * @tfm: cipher handle 798 * @key: buffer holding the key 799 * @keylen: length of the key in bytes 800 * 801 * The caller provided key is set for the keyed message digest cipher. The 802 * cipher handle must point to a keyed message digest cipher in order for this 803 * function to succeed. 804 * 805 * Context: Any context. 806 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 807 */ 808 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 809 unsigned int keylen); 810 811 /** 812 * crypto_shash_digest() - calculate message digest for buffer 813 * @desc: see crypto_shash_final() 814 * @data: see crypto_shash_update() 815 * @len: see crypto_shash_update() 816 * @out: see crypto_shash_final() 817 * 818 * This function is a "short-hand" for the function calls of crypto_shash_init, 819 * crypto_shash_update and crypto_shash_final. The parameters have the same 820 * meaning as discussed for those separate three functions. 821 * 822 * Context: Any context. 823 * Return: 0 if the message digest creation was successful; < 0 if an error 824 * occurred 825 */ 826 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 827 unsigned int len, u8 *out); 828 829 /** 830 * crypto_shash_tfm_digest() - calculate message digest for buffer 831 * @tfm: hash transformation object 832 * @data: see crypto_shash_update() 833 * @len: see crypto_shash_update() 834 * @out: see crypto_shash_final() 835 * 836 * This is a simplified version of crypto_shash_digest() for users who don't 837 * want to allocate their own hash descriptor (shash_desc). Instead, 838 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash) 839 * directly, and it allocates a hash descriptor on the stack internally. 840 * Note that this stack allocation may be fairly large. 841 * 842 * Context: Any context. 843 * Return: 0 on success; < 0 if an error occurred. 844 */ 845 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, 846 unsigned int len, u8 *out); 847 848 /** 849 * crypto_shash_export() - extract operational state for message digest 850 * @desc: reference to the operational state handle whose state is exported 851 * @out: output buffer of sufficient size that can hold the hash state 852 * 853 * This function exports the hash state of the operational state handle into the 854 * caller-allocated output buffer out which must have sufficient size (e.g. by 855 * calling crypto_shash_descsize). 856 * 857 * Context: Any context. 858 * Return: 0 if the export creation was successful; < 0 if an error occurred 859 */ 860 int crypto_shash_export(struct shash_desc *desc, void *out); 861 862 /** 863 * crypto_shash_import() - import operational state 864 * @desc: reference to the operational state handle the state imported into 865 * @in: buffer holding the state 866 * 867 * This function imports the hash state into the operational state handle from 868 * the input buffer. That buffer should have been generated with the 869 * crypto_ahash_export function. 870 * 871 * Context: Any context. 872 * Return: 0 if the import was successful; < 0 if an error occurred 873 */ 874 int crypto_shash_import(struct shash_desc *desc, const void *in); 875 876 /** 877 * crypto_shash_init() - (re)initialize message digest 878 * @desc: operational state handle that is already filled 879 * 880 * The call (re-)initializes the message digest referenced by the 881 * operational state handle. Any potentially existing state created by 882 * previous operations is discarded. 883 * 884 * Context: Any context. 885 * Return: 0 if the message digest initialization was successful; < 0 if an 886 * error occurred 887 */ crypto_shash_init(struct shash_desc * desc)888 static inline int crypto_shash_init(struct shash_desc *desc) 889 { 890 struct crypto_shash *tfm = desc->tfm; 891 892 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 893 return -ENOKEY; 894 895 return crypto_shash_alg(tfm)->init(desc); 896 } 897 898 /** 899 * crypto_shash_update() - add data to message digest for processing 900 * @desc: operational state handle that is already initialized 901 * @data: input data to be added to the message digest 902 * @len: length of the input data 903 * 904 * Updates the message digest state of the operational state handle. 905 * 906 * Context: Any context. 907 * Return: 0 if the message digest update was successful; < 0 if an error 908 * occurred 909 */ 910 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 911 unsigned int len); 912 913 /** 914 * crypto_shash_final() - calculate message digest 915 * @desc: operational state handle that is already filled with data 916 * @out: output buffer filled with the message digest 917 * 918 * Finalize the message digest operation and create the message digest 919 * based on all data added to the cipher handle. The message digest is placed 920 * into the output buffer. The caller must ensure that the output buffer is 921 * large enough by using crypto_shash_digestsize. 922 * 923 * Context: Any context. 924 * Return: 0 if the message digest creation was successful; < 0 if an error 925 * occurred 926 */ 927 int crypto_shash_final(struct shash_desc *desc, u8 *out); 928 929 /** 930 * crypto_shash_finup() - calculate message digest of buffer 931 * @desc: see crypto_shash_final() 932 * @data: see crypto_shash_update() 933 * @len: see crypto_shash_update() 934 * @out: see crypto_shash_final() 935 * 936 * This function is a "short-hand" for the function calls of 937 * crypto_shash_update and crypto_shash_final. The parameters have the same 938 * meaning as discussed for those separate functions. 939 * 940 * Context: Any context. 941 * Return: 0 if the message digest creation was successful; < 0 if an error 942 * occurred 943 */ 944 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 945 unsigned int len, u8 *out); 946 shash_desc_zero(struct shash_desc * desc)947 static inline void shash_desc_zero(struct shash_desc *desc) 948 { 949 memzero_explicit(desc, 950 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 951 } 952 953 #endif /* _CRYPTO_HASH_H */ 954