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