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 #include <linux/string.h> 18 19 struct crypto_ahash; 20 21 /** 22 * DOC: Message Digest Algorithm Definitions 23 * 24 * These data structures define modular message digest algorithm 25 * implementations, managed via crypto_register_ahash(), 26 * crypto_register_shash(), crypto_unregister_ahash() and 27 * crypto_unregister_shash(). 28 */ 29 30 /** 31 * struct hash_alg_common - define properties of message digest 32 * @digestsize: Size of the result of the transformation. A buffer of this size 33 * must be available to the @final and @finup calls, so they can 34 * store the resulting hash into it. For various predefined sizes, 35 * search include/crypto/ using 36 * git grep _DIGEST_SIZE include/crypto. 37 * @statesize: Size of the block for partial state of the transformation. A 38 * buffer of this size must be passed to the @export function as it 39 * will save the partial state of the transformation into it. On the 40 * other side, the @import function will load the state from a 41 * buffer of this size as well. 42 * @base: Start of data structure of cipher algorithm. The common data 43 * structure of crypto_alg contains information common to all ciphers. 44 * The hash_alg_common data structure now adds the hash-specific 45 * information. 46 */ 47 struct hash_alg_common { 48 unsigned int digestsize; 49 unsigned int statesize; 50 51 struct crypto_alg base; 52 }; 53 54 struct ahash_request { 55 struct crypto_async_request base; 56 57 unsigned int nbytes; 58 struct scatterlist *src; 59 u8 *result; 60 61 /* This field may only be used by the ahash API code. */ 62 void *priv; 63 64 void *__ctx[] CRYPTO_MINALIGN_ATTR; 65 }; 66 67 #define AHASH_REQUEST_ON_STACK(name, ahash) \ 68 char __##name##_desc[sizeof(struct ahash_request) + \ 69 crypto_ahash_reqsize(ahash)] CRYPTO_MINALIGN_ATTR; \ 70 struct ahash_request *name = (void *)__##name##_desc 71 72 /** 73 * struct ahash_alg - asynchronous message digest definition 74 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the 75 * state of the HASH transformation at the beginning. This shall fill in 76 * the internal structures used during the entire duration of the whole 77 * transformation. No data processing happens at this point. Driver code 78 * implementation must not use req->result. 79 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This 80 * function actually pushes blocks of data from upper layers into the 81 * driver, which then passes those to the hardware as seen fit. This 82 * function must not finalize the HASH transformation by calculating the 83 * final message digest as this only adds more data into the 84 * transformation. This function shall not modify the transformation 85 * context, as this function may be called in parallel with the same 86 * transformation object. Data processing can happen synchronously 87 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use 88 * req->result. 89 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the 90 * transformation and retrieves the resulting hash from the driver and 91 * pushes it back to upper layers. No data processing happens at this 92 * point unless hardware requires it to finish the transformation 93 * (then the data buffered by the device driver is processed). 94 * @finup: **[optional]** Combination of @update and @final. This function is effectively a 95 * combination of @update and @final calls issued in sequence. As some 96 * hardware cannot do @update and @final separately, this callback was 97 * added to allow such hardware to be used at least by IPsec. Data 98 * processing can happen synchronously [SHASH] or asynchronously [AHASH] 99 * at this point. 100 * @digest: Combination of @init and @update and @final. This function 101 * effectively behaves as the entire chain of operations, @init, 102 * @update and @final issued in sequence. Just like @finup, this was 103 * added for hardware which cannot do even the @finup, but can only do 104 * the whole transformation in one run. Data processing can happen 105 * synchronously [SHASH] or asynchronously [AHASH] at this point. 106 * @setkey: Set optional key used by the hashing algorithm. Intended to push 107 * optional key used by the hashing algorithm from upper layers into 108 * the driver. This function can store the key in the transformation 109 * context or can outright program it into the hardware. In the former 110 * case, one must be careful to program the key into the hardware at 111 * appropriate time and one must be careful that .setkey() can be 112 * called multiple times during the existence of the transformation 113 * object. Not all hashing algorithms do implement this function as it 114 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT 115 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement 116 * this function. This function must be called before any other of the 117 * @init, @update, @final, @finup, @digest is called. No data 118 * processing happens at this point. 119 * @export: Export partial state of the transformation. This function dumps the 120 * entire state of the ongoing transformation into a provided block of 121 * data so it can be @import 'ed back later on. This is useful in case 122 * you want to save partial result of the transformation after 123 * processing certain amount of data and reload this partial result 124 * multiple times later on for multiple re-use. No data processing 125 * happens at this point. Driver must not use req->result. 126 * @import: Import partial state of the transformation. This function loads the 127 * entire state of the ongoing transformation from a provided block of 128 * data so the transformation can continue from this point onward. No 129 * data processing happens at this point. Driver must not use 130 * req->result. 131 * @halg: see struct hash_alg_common 132 */ 133 struct ahash_alg { 134 int (*init)(struct ahash_request *req); 135 int (*update)(struct ahash_request *req); 136 int (*final)(struct ahash_request *req); 137 int (*finup)(struct ahash_request *req); 138 int (*digest)(struct ahash_request *req); 139 int (*export)(struct ahash_request *req, void *out); 140 int (*import)(struct ahash_request *req, const void *in); 141 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 142 unsigned int keylen); 143 144 struct hash_alg_common halg; 145 }; 146 147 struct shash_desc { 148 struct crypto_shash *tfm; 149 void *__ctx[] CRYPTO_MINALIGN_ATTR; 150 }; 151 152 #define HASH_MAX_DIGESTSIZE 64 153 154 /* 155 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' 156 * containing a 'struct sha3_state'. 157 */ 158 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360) 159 160 #define HASH_MAX_STATESIZE 512 161 162 #define SHASH_DESC_ON_STACK(shash, ctx) \ 163 char __##shash##_desc[sizeof(struct shash_desc) + \ 164 HASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \ 165 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc 166 167 /** 168 * struct shash_alg - synchronous message digest definition 169 * @init: see struct ahash_alg 170 * @update: see struct ahash_alg 171 * @final: see struct ahash_alg 172 * @finup: see struct ahash_alg 173 * @digest: see struct ahash_alg 174 * @export: see struct ahash_alg 175 * @import: see struct ahash_alg 176 * @setkey: see struct ahash_alg 177 * @digestsize: see struct ahash_alg 178 * @statesize: see struct ahash_alg 179 * @descsize: Size of the operational state for the message digest. This state 180 * size is the memory size that needs to be allocated for 181 * shash_desc.__ctx 182 * @base: internally used 183 */ 184 struct shash_alg { 185 int (*init)(struct shash_desc *desc); 186 int (*update)(struct shash_desc *desc, const u8 *data, 187 unsigned int len); 188 int (*final)(struct shash_desc *desc, u8 *out); 189 int (*finup)(struct shash_desc *desc, const u8 *data, 190 unsigned int len, u8 *out); 191 int (*digest)(struct shash_desc *desc, const u8 *data, 192 unsigned int len, u8 *out); 193 int (*export)(struct shash_desc *desc, void *out); 194 int (*import)(struct shash_desc *desc, const void *in); 195 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 196 unsigned int keylen); 197 198 unsigned int descsize; 199 200 /* These fields must match hash_alg_common. */ 201 unsigned int digestsize 202 __attribute__ ((aligned(__alignof__(struct hash_alg_common)))); 203 unsigned int statesize; 204 205 struct crypto_alg base; 206 }; 207 208 struct crypto_ahash { 209 int (*init)(struct ahash_request *req); 210 int (*update)(struct ahash_request *req); 211 int (*final)(struct ahash_request *req); 212 int (*finup)(struct ahash_request *req); 213 int (*digest)(struct ahash_request *req); 214 int (*export)(struct ahash_request *req, void *out); 215 int (*import)(struct ahash_request *req, const void *in); 216 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 217 unsigned int keylen); 218 219 unsigned int reqsize; 220 struct crypto_tfm base; 221 }; 222 223 struct crypto_shash { 224 unsigned int descsize; 225 struct crypto_tfm base; 226 }; 227 228 /** 229 * DOC: Asynchronous Message Digest API 230 * 231 * The asynchronous message digest API is used with the ciphers of type 232 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 233 * 234 * The asynchronous cipher operation discussion provided for the 235 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well. 236 */ 237 238 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 239 { 240 return container_of(tfm, struct crypto_ahash, base); 241 } 242 243 /** 244 * crypto_alloc_ahash() - allocate ahash cipher handle 245 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 246 * ahash cipher 247 * @type: specifies the type of the cipher 248 * @mask: specifies the mask for the cipher 249 * 250 * Allocate a cipher handle for an ahash. The returned struct 251 * crypto_ahash is the cipher handle that is required for any subsequent 252 * API invocation for that ahash. 253 * 254 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 255 * of an error, PTR_ERR() returns the error code. 256 */ 257 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 258 u32 mask); 259 260 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 261 { 262 return &tfm->base; 263 } 264 265 /** 266 * crypto_free_ahash() - zeroize and free the ahash handle 267 * @tfm: cipher handle to be freed 268 */ 269 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 270 { 271 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 272 } 273 274 /** 275 * crypto_has_ahash() - Search for the availability of an ahash. 276 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 277 * ahash 278 * @type: specifies the type of the ahash 279 * @mask: specifies the mask for the ahash 280 * 281 * Return: true when the ahash is known to the kernel crypto API; false 282 * otherwise 283 */ 284 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 285 286 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 287 { 288 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 289 } 290 291 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 292 { 293 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 294 } 295 296 static inline unsigned int crypto_ahash_alignmask( 297 struct crypto_ahash *tfm) 298 { 299 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm)); 300 } 301 302 /** 303 * crypto_ahash_blocksize() - obtain block size for cipher 304 * @tfm: cipher handle 305 * 306 * The block size for the message digest cipher referenced with the cipher 307 * handle is returned. 308 * 309 * Return: block size of cipher 310 */ 311 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 312 { 313 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 314 } 315 316 static inline struct hash_alg_common *__crypto_hash_alg_common( 317 struct crypto_alg *alg) 318 { 319 return container_of(alg, struct hash_alg_common, base); 320 } 321 322 static inline struct hash_alg_common *crypto_hash_alg_common( 323 struct crypto_ahash *tfm) 324 { 325 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 326 } 327 328 /** 329 * crypto_ahash_digestsize() - obtain message digest size 330 * @tfm: cipher handle 331 * 332 * The size for the message digest created by the message digest cipher 333 * referenced with the cipher handle is returned. 334 * 335 * 336 * Return: message digest size of cipher 337 */ 338 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 339 { 340 return crypto_hash_alg_common(tfm)->digestsize; 341 } 342 343 /** 344 * crypto_ahash_statesize() - obtain size of the ahash state 345 * @tfm: cipher handle 346 * 347 * Return the size of the ahash state. With the crypto_ahash_export() 348 * function, the caller can export the state into a buffer whose size is 349 * defined with this function. 350 * 351 * Return: size of the ahash state 352 */ 353 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 354 { 355 return crypto_hash_alg_common(tfm)->statesize; 356 } 357 358 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 359 { 360 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 361 } 362 363 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 364 { 365 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 366 } 367 368 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 369 { 370 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 371 } 372 373 /** 374 * crypto_ahash_reqtfm() - obtain cipher handle from request 375 * @req: asynchronous request handle that contains the reference to the ahash 376 * cipher handle 377 * 378 * Return the ahash cipher handle that is registered with the asynchronous 379 * request handle ahash_request. 380 * 381 * Return: ahash cipher handle 382 */ 383 static inline struct crypto_ahash *crypto_ahash_reqtfm( 384 struct ahash_request *req) 385 { 386 return __crypto_ahash_cast(req->base.tfm); 387 } 388 389 /** 390 * crypto_ahash_reqsize() - obtain size of the request data structure 391 * @tfm: cipher handle 392 * 393 * Return: size of the request data 394 */ 395 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 396 { 397 return tfm->reqsize; 398 } 399 400 static inline void *ahash_request_ctx(struct ahash_request *req) 401 { 402 return req->__ctx; 403 } 404 405 /** 406 * crypto_ahash_setkey - set key for cipher handle 407 * @tfm: cipher handle 408 * @key: buffer holding the key 409 * @keylen: length of the key in bytes 410 * 411 * The caller provided key is set for the ahash cipher. The cipher 412 * handle must point to a keyed hash in order for this function to succeed. 413 * 414 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 415 */ 416 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 417 unsigned int keylen); 418 419 /** 420 * crypto_ahash_finup() - update and finalize message digest 421 * @req: reference to the ahash_request handle that holds all information 422 * needed to perform the cipher operation 423 * 424 * This function is a "short-hand" for the function calls of 425 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 426 * meaning as discussed for those separate functions. 427 * 428 * Return: see crypto_ahash_final() 429 */ 430 int crypto_ahash_finup(struct ahash_request *req); 431 432 /** 433 * crypto_ahash_final() - calculate message digest 434 * @req: reference to the ahash_request handle that holds all information 435 * needed to perform the cipher operation 436 * 437 * Finalize the message digest operation and create the message digest 438 * based on all data added to the cipher handle. The message digest is placed 439 * into the output buffer registered with the ahash_request handle. 440 * 441 * Return: 442 * 0 if the message digest was successfully calculated; 443 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later; 444 * -EBUSY if queue is full and request should be resubmitted later; 445 * other < 0 if an error occurred 446 */ 447 int crypto_ahash_final(struct ahash_request *req); 448 449 /** 450 * crypto_ahash_digest() - calculate message digest for a buffer 451 * @req: reference to the ahash_request handle that holds all information 452 * needed to perform the cipher operation 453 * 454 * This function is a "short-hand" for the function calls of crypto_ahash_init, 455 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 456 * meaning as discussed for those separate three functions. 457 * 458 * Return: see crypto_ahash_final() 459 */ 460 int crypto_ahash_digest(struct ahash_request *req); 461 462 /** 463 * crypto_ahash_export() - extract current message digest state 464 * @req: reference to the ahash_request handle whose state is exported 465 * @out: output buffer of sufficient size that can hold the hash state 466 * 467 * This function exports the hash state of the ahash_request handle into the 468 * caller-allocated output buffer out which must have sufficient size (e.g. by 469 * calling crypto_ahash_statesize()). 470 * 471 * Return: 0 if the export was successful; < 0 if an error occurred 472 */ 473 static inline int crypto_ahash_export(struct ahash_request *req, void *out) 474 { 475 return crypto_ahash_reqtfm(req)->export(req, out); 476 } 477 478 /** 479 * crypto_ahash_import() - import message digest state 480 * @req: reference to ahash_request handle the state is imported into 481 * @in: buffer holding the state 482 * 483 * This function imports the hash state into the ahash_request handle from the 484 * input buffer. That buffer should have been generated with the 485 * crypto_ahash_export function. 486 * 487 * Return: 0 if the import was successful; < 0 if an error occurred 488 */ 489 static inline int crypto_ahash_import(struct ahash_request *req, const void *in) 490 { 491 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 492 493 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 494 return -ENOKEY; 495 496 return tfm->import(req, in); 497 } 498 499 /** 500 * crypto_ahash_init() - (re)initialize message digest handle 501 * @req: ahash_request handle that already is initialized with all necessary 502 * data using the ahash_request_* API functions 503 * 504 * The call (re-)initializes the message digest referenced by the ahash_request 505 * handle. Any potentially existing state created by previous operations is 506 * discarded. 507 * 508 * Return: see crypto_ahash_final() 509 */ 510 static inline int crypto_ahash_init(struct ahash_request *req) 511 { 512 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 513 514 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 515 return -ENOKEY; 516 517 return tfm->init(req); 518 } 519 520 /** 521 * crypto_ahash_update() - add data to message digest for processing 522 * @req: ahash_request handle that was previously initialized with the 523 * crypto_ahash_init call. 524 * 525 * Updates the message digest state of the &ahash_request handle. The input data 526 * is pointed to by the scatter/gather list registered in the &ahash_request 527 * handle 528 * 529 * Return: see crypto_ahash_final() 530 */ 531 static inline int crypto_ahash_update(struct ahash_request *req) 532 { 533 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 534 struct crypto_alg *alg = tfm->base.__crt_alg; 535 unsigned int nbytes = req->nbytes; 536 int ret; 537 538 crypto_stats_get(alg); 539 ret = crypto_ahash_reqtfm(req)->update(req); 540 crypto_stats_ahash_update(nbytes, ret, alg); 541 return ret; 542 } 543 544 /** 545 * DOC: Asynchronous Hash Request Handle 546 * 547 * The &ahash_request data structure contains all pointers to data 548 * required for the asynchronous cipher operation. This includes the cipher 549 * handle (which can be used by multiple &ahash_request instances), pointer 550 * to plaintext and the message digest output buffer, asynchronous callback 551 * function, etc. It acts as a handle to the ahash_request_* API calls in a 552 * similar way as ahash handle to the crypto_ahash_* API calls. 553 */ 554 555 /** 556 * ahash_request_set_tfm() - update cipher handle reference in request 557 * @req: request handle to be modified 558 * @tfm: cipher handle that shall be added to the request handle 559 * 560 * Allow the caller to replace the existing ahash handle in the request 561 * data structure with a different one. 562 */ 563 static inline void ahash_request_set_tfm(struct ahash_request *req, 564 struct crypto_ahash *tfm) 565 { 566 req->base.tfm = crypto_ahash_tfm(tfm); 567 } 568 569 /** 570 * ahash_request_alloc() - allocate request data structure 571 * @tfm: cipher handle to be registered with the request 572 * @gfp: memory allocation flag that is handed to kmalloc by the API call. 573 * 574 * Allocate the request data structure that must be used with the ahash 575 * message digest API calls. During 576 * the allocation, the provided ahash handle 577 * is registered in the request data structure. 578 * 579 * Return: allocated request handle in case of success, or NULL if out of memory 580 */ 581 static inline struct ahash_request *ahash_request_alloc( 582 struct crypto_ahash *tfm, gfp_t gfp) 583 { 584 struct ahash_request *req; 585 586 req = kmalloc(sizeof(struct ahash_request) + 587 crypto_ahash_reqsize(tfm), gfp); 588 589 if (likely(req)) 590 ahash_request_set_tfm(req, tfm); 591 592 return req; 593 } 594 595 /** 596 * ahash_request_free() - zeroize and free the request data structure 597 * @req: request data structure cipher handle to be freed 598 */ 599 static inline void ahash_request_free(struct ahash_request *req) 600 { 601 kzfree(req); 602 } 603 604 static inline void ahash_request_zero(struct ahash_request *req) 605 { 606 memzero_explicit(req, sizeof(*req) + 607 crypto_ahash_reqsize(crypto_ahash_reqtfm(req))); 608 } 609 610 static inline struct ahash_request *ahash_request_cast( 611 struct crypto_async_request *req) 612 { 613 return container_of(req, struct ahash_request, base); 614 } 615 616 /** 617 * ahash_request_set_callback() - set asynchronous callback function 618 * @req: request handle 619 * @flags: specify zero or an ORing of the flags 620 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and 621 * increase the wait queue beyond the initial maximum size; 622 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep 623 * @compl: callback function pointer to be registered with the request handle 624 * @data: The data pointer refers to memory that is not used by the kernel 625 * crypto API, but provided to the callback function for it to use. Here, 626 * the caller can provide a reference to memory the callback function can 627 * operate on. As the callback function is invoked asynchronously to the 628 * related functionality, it may need to access data structures of the 629 * related functionality which can be referenced using this pointer. The 630 * callback function can access the memory via the "data" field in the 631 * &crypto_async_request data structure provided to the callback function. 632 * 633 * This function allows setting the callback function that is triggered once 634 * the cipher operation completes. 635 * 636 * The callback function is registered with the &ahash_request handle and 637 * must comply with the following template:: 638 * 639 * void callback_function(struct crypto_async_request *req, int error) 640 */ 641 static inline void ahash_request_set_callback(struct ahash_request *req, 642 u32 flags, 643 crypto_completion_t compl, 644 void *data) 645 { 646 req->base.complete = compl; 647 req->base.data = data; 648 req->base.flags = flags; 649 } 650 651 /** 652 * ahash_request_set_crypt() - set data buffers 653 * @req: ahash_request handle to be updated 654 * @src: source scatter/gather list 655 * @result: buffer that is filled with the message digest -- the caller must 656 * ensure that the buffer has sufficient space by, for example, calling 657 * crypto_ahash_digestsize() 658 * @nbytes: number of bytes to process from the source scatter/gather list 659 * 660 * By using this call, the caller references the source scatter/gather list. 661 * The source scatter/gather list points to the data the message digest is to 662 * be calculated for. 663 */ 664 static inline void ahash_request_set_crypt(struct ahash_request *req, 665 struct scatterlist *src, u8 *result, 666 unsigned int nbytes) 667 { 668 req->src = src; 669 req->nbytes = nbytes; 670 req->result = result; 671 } 672 673 /** 674 * DOC: Synchronous Message Digest API 675 * 676 * The synchronous message digest API is used with the ciphers of type 677 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) 678 * 679 * The message digest API is able to maintain state information for the 680 * caller. 681 * 682 * The synchronous message digest API can store user-related context in in its 683 * shash_desc request data structure. 684 */ 685 686 /** 687 * crypto_alloc_shash() - allocate message digest handle 688 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 689 * message digest cipher 690 * @type: specifies the type of the cipher 691 * @mask: specifies the mask for the cipher 692 * 693 * Allocate a cipher handle for a message digest. The returned &struct 694 * crypto_shash is the cipher handle that is required for any subsequent 695 * API invocation for that message digest. 696 * 697 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 698 * of an error, PTR_ERR() returns the error code. 699 */ 700 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 701 u32 mask); 702 703 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 704 { 705 return &tfm->base; 706 } 707 708 /** 709 * crypto_free_shash() - zeroize and free the message digest handle 710 * @tfm: cipher handle to be freed 711 */ 712 static inline void crypto_free_shash(struct crypto_shash *tfm) 713 { 714 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 715 } 716 717 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 718 { 719 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 720 } 721 722 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 723 { 724 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm)); 725 } 726 727 static inline unsigned int crypto_shash_alignmask( 728 struct crypto_shash *tfm) 729 { 730 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm)); 731 } 732 733 /** 734 * crypto_shash_blocksize() - obtain block size for cipher 735 * @tfm: cipher handle 736 * 737 * The block size for the message digest cipher referenced with the cipher 738 * handle is returned. 739 * 740 * Return: block size of cipher 741 */ 742 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) 743 { 744 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm)); 745 } 746 747 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) 748 { 749 return container_of(alg, struct shash_alg, base); 750 } 751 752 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) 753 { 754 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg); 755 } 756 757 /** 758 * crypto_shash_digestsize() - obtain message digest size 759 * @tfm: cipher handle 760 * 761 * The size for the message digest created by the message digest cipher 762 * referenced with the cipher handle is returned. 763 * 764 * Return: digest size of cipher 765 */ 766 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) 767 { 768 return crypto_shash_alg(tfm)->digestsize; 769 } 770 771 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) 772 { 773 return crypto_shash_alg(tfm)->statesize; 774 } 775 776 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) 777 { 778 return crypto_tfm_get_flags(crypto_shash_tfm(tfm)); 779 } 780 781 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) 782 { 783 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags); 784 } 785 786 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) 787 { 788 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags); 789 } 790 791 /** 792 * crypto_shash_descsize() - obtain the operational state size 793 * @tfm: cipher handle 794 * 795 * The size of the operational state the cipher needs during operation is 796 * returned for the hash referenced with the cipher handle. This size is 797 * required to calculate the memory requirements to allow the caller allocating 798 * sufficient memory for operational state. 799 * 800 * The operational state is defined with struct shash_desc where the size of 801 * that data structure is to be calculated as 802 * sizeof(struct shash_desc) + crypto_shash_descsize(alg) 803 * 804 * Return: size of the operational state 805 */ 806 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) 807 { 808 return tfm->descsize; 809 } 810 811 static inline void *shash_desc_ctx(struct shash_desc *desc) 812 { 813 return desc->__ctx; 814 } 815 816 /** 817 * crypto_shash_setkey() - set key for message digest 818 * @tfm: cipher handle 819 * @key: buffer holding the key 820 * @keylen: length of the key in bytes 821 * 822 * The caller provided key is set for the keyed message digest cipher. The 823 * cipher handle must point to a keyed message digest cipher in order for this 824 * function to succeed. 825 * 826 * Context: Any context. 827 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 828 */ 829 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 830 unsigned int keylen); 831 832 /** 833 * crypto_shash_digest() - calculate message digest for buffer 834 * @desc: see crypto_shash_final() 835 * @data: see crypto_shash_update() 836 * @len: see crypto_shash_update() 837 * @out: see crypto_shash_final() 838 * 839 * This function is a "short-hand" for the function calls of crypto_shash_init, 840 * crypto_shash_update and crypto_shash_final. The parameters have the same 841 * meaning as discussed for those separate three functions. 842 * 843 * Context: Any context. 844 * Return: 0 if the message digest creation was successful; < 0 if an error 845 * occurred 846 */ 847 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 848 unsigned int len, u8 *out); 849 850 /** 851 * crypto_shash_export() - extract operational state for message digest 852 * @desc: reference to the operational state handle whose state is exported 853 * @out: output buffer of sufficient size that can hold the hash state 854 * 855 * This function exports the hash state of the operational state handle into the 856 * caller-allocated output buffer out which must have sufficient size (e.g. by 857 * calling crypto_shash_descsize). 858 * 859 * Context: Any context. 860 * Return: 0 if the export creation was successful; < 0 if an error occurred 861 */ 862 static inline int crypto_shash_export(struct shash_desc *desc, void *out) 863 { 864 return crypto_shash_alg(desc->tfm)->export(desc, out); 865 } 866 867 /** 868 * crypto_shash_import() - import operational state 869 * @desc: reference to the operational state handle the state imported into 870 * @in: buffer holding the state 871 * 872 * This function imports the hash state into the operational state handle from 873 * the input buffer. That buffer should have been generated with the 874 * crypto_ahash_export function. 875 * 876 * Context: Any context. 877 * Return: 0 if the import was successful; < 0 if an error occurred 878 */ 879 static inline int crypto_shash_import(struct shash_desc *desc, const void *in) 880 { 881 struct crypto_shash *tfm = desc->tfm; 882 883 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 884 return -ENOKEY; 885 886 return crypto_shash_alg(tfm)->import(desc, in); 887 } 888 889 /** 890 * crypto_shash_init() - (re)initialize message digest 891 * @desc: operational state handle that is already filled 892 * 893 * The call (re-)initializes the message digest referenced by the 894 * operational state handle. Any potentially existing state created by 895 * previous operations is discarded. 896 * 897 * Context: Any context. 898 * Return: 0 if the message digest initialization was successful; < 0 if an 899 * error occurred 900 */ 901 static inline int crypto_shash_init(struct shash_desc *desc) 902 { 903 struct crypto_shash *tfm = desc->tfm; 904 905 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 906 return -ENOKEY; 907 908 return crypto_shash_alg(tfm)->init(desc); 909 } 910 911 /** 912 * crypto_shash_update() - add data to message digest for processing 913 * @desc: operational state handle that is already initialized 914 * @data: input data to be added to the message digest 915 * @len: length of the input data 916 * 917 * Updates the message digest state of the operational state handle. 918 * 919 * Context: Any context. 920 * Return: 0 if the message digest update was successful; < 0 if an error 921 * occurred 922 */ 923 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 924 unsigned int len); 925 926 /** 927 * crypto_shash_final() - calculate message digest 928 * @desc: operational state handle that is already filled with data 929 * @out: output buffer filled with the message digest 930 * 931 * Finalize the message digest operation and create the message digest 932 * based on all data added to the cipher handle. The message digest is placed 933 * into the output buffer. The caller must ensure that the output buffer is 934 * large enough by using crypto_shash_digestsize. 935 * 936 * Context: Any context. 937 * Return: 0 if the message digest creation was successful; < 0 if an error 938 * occurred 939 */ 940 int crypto_shash_final(struct shash_desc *desc, u8 *out); 941 942 /** 943 * crypto_shash_finup() - calculate message digest of buffer 944 * @desc: see crypto_shash_final() 945 * @data: see crypto_shash_update() 946 * @len: see crypto_shash_update() 947 * @out: see crypto_shash_final() 948 * 949 * This function is a "short-hand" for the function calls of 950 * crypto_shash_update and crypto_shash_final. The parameters have the same 951 * meaning as discussed for those separate functions. 952 * 953 * Context: Any context. 954 * Return: 0 if the message digest creation was successful; < 0 if an error 955 * occurred 956 */ 957 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 958 unsigned int len, u8 *out); 959 960 static inline void shash_desc_zero(struct shash_desc *desc) 961 { 962 memzero_explicit(desc, 963 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 964 } 965 966 #endif /* _CRYPTO_HASH_H */ 967