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/crypto.h> 12 #include <linux/string.h> 13 14 struct crypto_ahash; 15 16 /** 17 * DOC: Message Digest Algorithm Definitions 18 * 19 * These data structures define modular message digest algorithm 20 * implementations, managed via crypto_register_ahash(), 21 * crypto_register_shash(), crypto_unregister_ahash() and 22 * crypto_unregister_shash(). 23 */ 24 25 /** 26 * struct hash_alg_common - define properties of message digest 27 * @digestsize: Size of the result of the transformation. A buffer of this size 28 * must be available to the @final and @finup calls, so they can 29 * store the resulting hash into it. For various predefined sizes, 30 * search include/crypto/ using 31 * git grep _DIGEST_SIZE include/crypto. 32 * @statesize: Size of the block for partial state of the transformation. A 33 * buffer of this size must be passed to the @export function as it 34 * will save the partial state of the transformation into it. On the 35 * other side, the @import function will load the state from a 36 * buffer of this size as well. 37 * @base: Start of data structure of cipher algorithm. The common data 38 * structure of crypto_alg contains information common to all ciphers. 39 * The hash_alg_common data structure now adds the hash-specific 40 * information. 41 */ 42 struct hash_alg_common { 43 unsigned int digestsize; 44 unsigned int statesize; 45 46 struct crypto_alg base; 47 }; 48 49 struct ahash_request { 50 struct crypto_async_request base; 51 52 unsigned int nbytes; 53 struct scatterlist *src; 54 u8 *result; 55 56 /* This field may only be used by the ahash API code. */ 57 void *priv; 58 59 void *__ctx[] CRYPTO_MINALIGN_ATTR; 60 }; 61 62 #define AHASH_REQUEST_ON_STACK(name, ahash) \ 63 char __##name##_desc[sizeof(struct ahash_request) + \ 64 crypto_ahash_reqsize(ahash)] CRYPTO_MINALIGN_ATTR; \ 65 struct ahash_request *name = (void *)__##name##_desc 66 67 /** 68 * struct ahash_alg - asynchronous message digest definition 69 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the 70 * state of the HASH transformation at the beginning. This shall fill in 71 * the internal structures used during the entire duration of the whole 72 * transformation. No data processing happens at this point. Driver code 73 * implementation must not use req->result. 74 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This 75 * function actually pushes blocks of data from upper layers into the 76 * driver, which then passes those to the hardware as seen fit. This 77 * function must not finalize the HASH transformation by calculating the 78 * final message digest as this only adds more data into the 79 * transformation. This function shall not modify the transformation 80 * context, as this function may be called in parallel with the same 81 * transformation object. Data processing can happen synchronously 82 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use 83 * req->result. 84 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the 85 * transformation and retrieves the resulting hash from the driver and 86 * pushes it back to upper layers. No data processing happens at this 87 * point unless hardware requires it to finish the transformation 88 * (then the data buffered by the device driver is processed). 89 * @finup: **[optional]** Combination of @update and @final. This function is effectively a 90 * combination of @update and @final calls issued in sequence. As some 91 * hardware cannot do @update and @final separately, this callback was 92 * added to allow such hardware to be used at least by IPsec. Data 93 * processing can happen synchronously [SHASH] or asynchronously [AHASH] 94 * at this point. 95 * @digest: Combination of @init and @update and @final. This function 96 * effectively behaves as the entire chain of operations, @init, 97 * @update and @final issued in sequence. Just like @finup, this was 98 * added for hardware which cannot do even the @finup, but can only do 99 * the whole transformation in one run. Data processing can happen 100 * synchronously [SHASH] or asynchronously [AHASH] at this point. 101 * @setkey: Set optional key used by the hashing algorithm. Intended to push 102 * optional key used by the hashing algorithm from upper layers into 103 * the driver. This function can store the key in the transformation 104 * context or can outright program it into the hardware. In the former 105 * case, one must be careful to program the key into the hardware at 106 * appropriate time and one must be careful that .setkey() can be 107 * called multiple times during the existence of the transformation 108 * object. Not all hashing algorithms do implement this function as it 109 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT 110 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement 111 * this function. This function must be called before any other of the 112 * @init, @update, @final, @finup, @digest is called. No data 113 * processing happens at this point. 114 * @export: Export partial state of the transformation. This function dumps the 115 * entire state of the ongoing transformation into a provided block of 116 * data so it can be @import 'ed back later on. This is useful in case 117 * you want to save partial result of the transformation after 118 * processing certain amount of data and reload this partial result 119 * multiple times later on for multiple re-use. No data processing 120 * happens at this point. Driver must not use req->result. 121 * @import: Import partial state of the transformation. This function loads the 122 * entire state of the ongoing transformation from a provided block of 123 * data so the transformation can continue from this point onward. No 124 * data processing happens at this point. Driver must not use 125 * req->result. 126 * @halg: see struct hash_alg_common 127 */ 128 struct ahash_alg { 129 int (*init)(struct ahash_request *req); 130 int (*update)(struct ahash_request *req); 131 int (*final)(struct ahash_request *req); 132 int (*finup)(struct ahash_request *req); 133 int (*digest)(struct ahash_request *req); 134 int (*export)(struct ahash_request *req, void *out); 135 int (*import)(struct ahash_request *req, const void *in); 136 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 137 unsigned int keylen); 138 139 struct hash_alg_common halg; 140 }; 141 142 struct shash_desc { 143 struct crypto_shash *tfm; 144 void *__ctx[] CRYPTO_MINALIGN_ATTR; 145 }; 146 147 #define HASH_MAX_DIGESTSIZE 64 148 149 /* 150 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' 151 * containing a 'struct sha3_state'. 152 */ 153 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360) 154 155 #define HASH_MAX_STATESIZE 512 156 157 #define SHASH_DESC_ON_STACK(shash, ctx) \ 158 char __##shash##_desc[sizeof(struct shash_desc) + \ 159 HASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \ 160 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc 161 162 /** 163 * struct shash_alg - synchronous message digest definition 164 * @init: see struct ahash_alg 165 * @update: see struct ahash_alg 166 * @final: see struct ahash_alg 167 * @finup: see struct ahash_alg 168 * @digest: see struct ahash_alg 169 * @export: see struct ahash_alg 170 * @import: see struct ahash_alg 171 * @setkey: see struct ahash_alg 172 * @digestsize: see struct ahash_alg 173 * @statesize: see struct ahash_alg 174 * @descsize: Size of the operational state for the message digest. This state 175 * size is the memory size that needs to be allocated for 176 * shash_desc.__ctx 177 * @base: internally used 178 */ 179 struct shash_alg { 180 int (*init)(struct shash_desc *desc); 181 int (*update)(struct shash_desc *desc, const u8 *data, 182 unsigned int len); 183 int (*final)(struct shash_desc *desc, u8 *out); 184 int (*finup)(struct shash_desc *desc, const u8 *data, 185 unsigned int len, u8 *out); 186 int (*digest)(struct shash_desc *desc, const u8 *data, 187 unsigned int len, u8 *out); 188 int (*export)(struct shash_desc *desc, void *out); 189 int (*import)(struct shash_desc *desc, const void *in); 190 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 191 unsigned int keylen); 192 193 unsigned int descsize; 194 195 /* These fields must match hash_alg_common. */ 196 unsigned int digestsize 197 __attribute__ ((aligned(__alignof__(struct hash_alg_common)))); 198 unsigned int statesize; 199 200 struct crypto_alg base; 201 }; 202 203 struct crypto_ahash { 204 int (*init)(struct ahash_request *req); 205 int (*update)(struct ahash_request *req); 206 int (*final)(struct ahash_request *req); 207 int (*finup)(struct ahash_request *req); 208 int (*digest)(struct ahash_request *req); 209 int (*export)(struct ahash_request *req, void *out); 210 int (*import)(struct ahash_request *req, const void *in); 211 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 212 unsigned int keylen); 213 214 unsigned int reqsize; 215 struct crypto_tfm base; 216 }; 217 218 struct crypto_shash { 219 unsigned int descsize; 220 struct crypto_tfm base; 221 }; 222 223 /** 224 * DOC: Asynchronous Message Digest API 225 * 226 * The asynchronous message digest API is used with the ciphers of type 227 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 228 * 229 * The asynchronous cipher operation discussion provided for the 230 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well. 231 */ 232 233 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 234 { 235 return container_of(tfm, struct crypto_ahash, base); 236 } 237 238 /** 239 * crypto_alloc_ahash() - allocate ahash cipher handle 240 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 241 * ahash cipher 242 * @type: specifies the type of the cipher 243 * @mask: specifies the mask for the cipher 244 * 245 * Allocate a cipher handle for an ahash. The returned struct 246 * crypto_ahash is the cipher handle that is required for any subsequent 247 * API invocation for that ahash. 248 * 249 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 250 * of an error, PTR_ERR() returns the error code. 251 */ 252 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 253 u32 mask); 254 255 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 256 { 257 return &tfm->base; 258 } 259 260 /** 261 * crypto_free_ahash() - zeroize and free the ahash handle 262 * @tfm: cipher handle to be freed 263 */ 264 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 265 { 266 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 267 } 268 269 /** 270 * crypto_has_ahash() - Search for the availability of an ahash. 271 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 272 * ahash 273 * @type: specifies the type of the ahash 274 * @mask: specifies the mask for the ahash 275 * 276 * Return: true when the ahash is known to the kernel crypto API; false 277 * otherwise 278 */ 279 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 280 281 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 282 { 283 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 284 } 285 286 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 287 { 288 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 289 } 290 291 static inline unsigned int crypto_ahash_alignmask( 292 struct crypto_ahash *tfm) 293 { 294 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm)); 295 } 296 297 /** 298 * crypto_ahash_blocksize() - obtain block size for cipher 299 * @tfm: cipher handle 300 * 301 * The block size for the message digest cipher referenced with the cipher 302 * handle is returned. 303 * 304 * Return: block size of cipher 305 */ 306 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 307 { 308 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 309 } 310 311 static inline struct hash_alg_common *__crypto_hash_alg_common( 312 struct crypto_alg *alg) 313 { 314 return container_of(alg, struct hash_alg_common, base); 315 } 316 317 static inline struct hash_alg_common *crypto_hash_alg_common( 318 struct crypto_ahash *tfm) 319 { 320 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 321 } 322 323 /** 324 * crypto_ahash_digestsize() - obtain message digest size 325 * @tfm: cipher handle 326 * 327 * The size for the message digest created by the message digest cipher 328 * referenced with the cipher handle is returned. 329 * 330 * 331 * Return: message digest size of cipher 332 */ 333 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 334 { 335 return crypto_hash_alg_common(tfm)->digestsize; 336 } 337 338 /** 339 * crypto_ahash_statesize() - obtain size of the ahash state 340 * @tfm: cipher handle 341 * 342 * Return the size of the ahash state. With the crypto_ahash_export() 343 * function, the caller can export the state into a buffer whose size is 344 * defined with this function. 345 * 346 * Return: size of the ahash state 347 */ 348 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 349 { 350 return crypto_hash_alg_common(tfm)->statesize; 351 } 352 353 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 354 { 355 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 356 } 357 358 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 359 { 360 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 361 } 362 363 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 364 { 365 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 366 } 367 368 /** 369 * crypto_ahash_reqtfm() - obtain cipher handle from request 370 * @req: asynchronous request handle that contains the reference to the ahash 371 * cipher handle 372 * 373 * Return the ahash cipher handle that is registered with the asynchronous 374 * request handle ahash_request. 375 * 376 * Return: ahash cipher handle 377 */ 378 static inline struct crypto_ahash *crypto_ahash_reqtfm( 379 struct ahash_request *req) 380 { 381 return __crypto_ahash_cast(req->base.tfm); 382 } 383 384 /** 385 * crypto_ahash_reqsize() - obtain size of the request data structure 386 * @tfm: cipher handle 387 * 388 * Return: size of the request data 389 */ 390 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 391 { 392 return tfm->reqsize; 393 } 394 395 static inline void *ahash_request_ctx(struct ahash_request *req) 396 { 397 return req->__ctx; 398 } 399 400 /** 401 * crypto_ahash_setkey - set key for cipher handle 402 * @tfm: cipher handle 403 * @key: buffer holding the key 404 * @keylen: length of the key in bytes 405 * 406 * The caller provided key is set for the ahash cipher. The cipher 407 * handle must point to a keyed hash in order for this function to succeed. 408 * 409 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 410 */ 411 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 412 unsigned int keylen); 413 414 /** 415 * crypto_ahash_finup() - update and finalize message digest 416 * @req: reference to the ahash_request handle that holds all information 417 * needed to perform the cipher operation 418 * 419 * This function is a "short-hand" for the function calls of 420 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 421 * meaning as discussed for those separate functions. 422 * 423 * Return: see crypto_ahash_final() 424 */ 425 int crypto_ahash_finup(struct ahash_request *req); 426 427 /** 428 * crypto_ahash_final() - calculate message digest 429 * @req: reference to the ahash_request handle that holds all information 430 * needed to perform the cipher operation 431 * 432 * Finalize the message digest operation and create the message digest 433 * based on all data added to the cipher handle. The message digest is placed 434 * into the output buffer registered with the ahash_request handle. 435 * 436 * Return: 437 * 0 if the message digest was successfully calculated; 438 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later; 439 * -EBUSY if queue is full and request should be resubmitted later; 440 * other < 0 if an error occurred 441 */ 442 int crypto_ahash_final(struct ahash_request *req); 443 444 /** 445 * crypto_ahash_digest() - calculate message digest for a buffer 446 * @req: reference to the ahash_request handle that holds all information 447 * needed to perform the cipher operation 448 * 449 * This function is a "short-hand" for the function calls of crypto_ahash_init, 450 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 451 * meaning as discussed for those separate three functions. 452 * 453 * Return: see crypto_ahash_final() 454 */ 455 int crypto_ahash_digest(struct ahash_request *req); 456 457 /** 458 * crypto_ahash_export() - extract current message digest state 459 * @req: reference to the ahash_request handle whose state is exported 460 * @out: output buffer of sufficient size that can hold the hash state 461 * 462 * This function exports the hash state of the ahash_request handle into the 463 * caller-allocated output buffer out which must have sufficient size (e.g. by 464 * calling crypto_ahash_statesize()). 465 * 466 * Return: 0 if the export was successful; < 0 if an error occurred 467 */ 468 static inline int crypto_ahash_export(struct ahash_request *req, void *out) 469 { 470 return crypto_ahash_reqtfm(req)->export(req, out); 471 } 472 473 /** 474 * crypto_ahash_import() - import message digest state 475 * @req: reference to ahash_request handle the state is imported into 476 * @in: buffer holding the state 477 * 478 * This function imports the hash state into the ahash_request handle from the 479 * input buffer. That buffer should have been generated with the 480 * crypto_ahash_export function. 481 * 482 * Return: 0 if the import was successful; < 0 if an error occurred 483 */ 484 static inline int crypto_ahash_import(struct ahash_request *req, const void *in) 485 { 486 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 487 488 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 489 return -ENOKEY; 490 491 return tfm->import(req, in); 492 } 493 494 /** 495 * crypto_ahash_init() - (re)initialize message digest handle 496 * @req: ahash_request handle that already is initialized with all necessary 497 * data using the ahash_request_* API functions 498 * 499 * The call (re-)initializes the message digest referenced by the ahash_request 500 * handle. Any potentially existing state created by previous operations is 501 * discarded. 502 * 503 * Return: see crypto_ahash_final() 504 */ 505 static inline int crypto_ahash_init(struct ahash_request *req) 506 { 507 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 508 509 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 510 return -ENOKEY; 511 512 return tfm->init(req); 513 } 514 515 /** 516 * crypto_ahash_update() - add data to message digest for processing 517 * @req: ahash_request handle that was previously initialized with the 518 * crypto_ahash_init call. 519 * 520 * Updates the message digest state of the &ahash_request handle. The input data 521 * is pointed to by the scatter/gather list registered in the &ahash_request 522 * handle 523 * 524 * Return: see crypto_ahash_final() 525 */ 526 static inline int crypto_ahash_update(struct ahash_request *req) 527 { 528 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 529 struct crypto_alg *alg = tfm->base.__crt_alg; 530 unsigned int nbytes = req->nbytes; 531 int ret; 532 533 crypto_stats_get(alg); 534 ret = crypto_ahash_reqtfm(req)->update(req); 535 crypto_stats_ahash_update(nbytes, ret, alg); 536 return ret; 537 } 538 539 /** 540 * DOC: Asynchronous Hash Request Handle 541 * 542 * The &ahash_request data structure contains all pointers to data 543 * required for the asynchronous cipher operation. This includes the cipher 544 * handle (which can be used by multiple &ahash_request instances), pointer 545 * to plaintext and the message digest output buffer, asynchronous callback 546 * function, etc. It acts as a handle to the ahash_request_* API calls in a 547 * similar way as ahash handle to the crypto_ahash_* API calls. 548 */ 549 550 /** 551 * ahash_request_set_tfm() - update cipher handle reference in request 552 * @req: request handle to be modified 553 * @tfm: cipher handle that shall be added to the request handle 554 * 555 * Allow the caller to replace the existing ahash handle in the request 556 * data structure with a different one. 557 */ 558 static inline void ahash_request_set_tfm(struct ahash_request *req, 559 struct crypto_ahash *tfm) 560 { 561 req->base.tfm = crypto_ahash_tfm(tfm); 562 } 563 564 /** 565 * ahash_request_alloc() - allocate request data structure 566 * @tfm: cipher handle to be registered with the request 567 * @gfp: memory allocation flag that is handed to kmalloc by the API call. 568 * 569 * Allocate the request data structure that must be used with the ahash 570 * message digest API calls. During 571 * the allocation, the provided ahash handle 572 * is registered in the request data structure. 573 * 574 * Return: allocated request handle in case of success, or NULL if out of memory 575 */ 576 static inline struct ahash_request *ahash_request_alloc( 577 struct crypto_ahash *tfm, gfp_t gfp) 578 { 579 struct ahash_request *req; 580 581 req = kmalloc(sizeof(struct ahash_request) + 582 crypto_ahash_reqsize(tfm), gfp); 583 584 if (likely(req)) 585 ahash_request_set_tfm(req, tfm); 586 587 return req; 588 } 589 590 /** 591 * ahash_request_free() - zeroize and free the request data structure 592 * @req: request data structure cipher handle to be freed 593 */ 594 static inline void ahash_request_free(struct ahash_request *req) 595 { 596 kzfree(req); 597 } 598 599 static inline void ahash_request_zero(struct ahash_request *req) 600 { 601 memzero_explicit(req, sizeof(*req) + 602 crypto_ahash_reqsize(crypto_ahash_reqtfm(req))); 603 } 604 605 static inline struct ahash_request *ahash_request_cast( 606 struct crypto_async_request *req) 607 { 608 return container_of(req, struct ahash_request, base); 609 } 610 611 /** 612 * ahash_request_set_callback() - set asynchronous callback function 613 * @req: request handle 614 * @flags: specify zero or an ORing of the flags 615 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and 616 * increase the wait queue beyond the initial maximum size; 617 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep 618 * @compl: callback function pointer to be registered with the request handle 619 * @data: The data pointer refers to memory that is not used by the kernel 620 * crypto API, but provided to the callback function for it to use. Here, 621 * the caller can provide a reference to memory the callback function can 622 * operate on. As the callback function is invoked asynchronously to the 623 * related functionality, it may need to access data structures of the 624 * related functionality which can be referenced using this pointer. The 625 * callback function can access the memory via the "data" field in the 626 * &crypto_async_request data structure provided to the callback function. 627 * 628 * This function allows setting the callback function that is triggered once 629 * the cipher operation completes. 630 * 631 * The callback function is registered with the &ahash_request handle and 632 * must comply with the following template:: 633 * 634 * void callback_function(struct crypto_async_request *req, int error) 635 */ 636 static inline void ahash_request_set_callback(struct ahash_request *req, 637 u32 flags, 638 crypto_completion_t compl, 639 void *data) 640 { 641 req->base.complete = compl; 642 req->base.data = data; 643 req->base.flags = flags; 644 } 645 646 /** 647 * ahash_request_set_crypt() - set data buffers 648 * @req: ahash_request handle to be updated 649 * @src: source scatter/gather list 650 * @result: buffer that is filled with the message digest -- the caller must 651 * ensure that the buffer has sufficient space by, for example, calling 652 * crypto_ahash_digestsize() 653 * @nbytes: number of bytes to process from the source scatter/gather list 654 * 655 * By using this call, the caller references the source scatter/gather list. 656 * The source scatter/gather list points to the data the message digest is to 657 * be calculated for. 658 */ 659 static inline void ahash_request_set_crypt(struct ahash_request *req, 660 struct scatterlist *src, u8 *result, 661 unsigned int nbytes) 662 { 663 req->src = src; 664 req->nbytes = nbytes; 665 req->result = result; 666 } 667 668 /** 669 * DOC: Synchronous Message Digest API 670 * 671 * The synchronous message digest API is used with the ciphers of type 672 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) 673 * 674 * The message digest API is able to maintain state information for the 675 * caller. 676 * 677 * The synchronous message digest API can store user-related context in in its 678 * shash_desc request data structure. 679 */ 680 681 /** 682 * crypto_alloc_shash() - allocate message digest handle 683 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 684 * message digest cipher 685 * @type: specifies the type of the cipher 686 * @mask: specifies the mask for the cipher 687 * 688 * Allocate a cipher handle for a message digest. The returned &struct 689 * crypto_shash is the cipher handle that is required for any subsequent 690 * API invocation for that message digest. 691 * 692 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 693 * of an error, PTR_ERR() returns the error code. 694 */ 695 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 696 u32 mask); 697 698 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 699 { 700 return &tfm->base; 701 } 702 703 /** 704 * crypto_free_shash() - zeroize and free the message digest handle 705 * @tfm: cipher handle to be freed 706 */ 707 static inline void crypto_free_shash(struct crypto_shash *tfm) 708 { 709 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 710 } 711 712 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 713 { 714 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 715 } 716 717 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 718 { 719 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm)); 720 } 721 722 static inline unsigned int crypto_shash_alignmask( 723 struct crypto_shash *tfm) 724 { 725 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm)); 726 } 727 728 /** 729 * crypto_shash_blocksize() - obtain block size for cipher 730 * @tfm: cipher handle 731 * 732 * The block size for the message digest cipher referenced with the cipher 733 * handle is returned. 734 * 735 * Return: block size of cipher 736 */ 737 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) 738 { 739 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm)); 740 } 741 742 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) 743 { 744 return container_of(alg, struct shash_alg, base); 745 } 746 747 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) 748 { 749 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg); 750 } 751 752 /** 753 * crypto_shash_digestsize() - obtain message digest size 754 * @tfm: cipher handle 755 * 756 * The size for the message digest created by the message digest cipher 757 * referenced with the cipher handle is returned. 758 * 759 * Return: digest size of cipher 760 */ 761 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) 762 { 763 return crypto_shash_alg(tfm)->digestsize; 764 } 765 766 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) 767 { 768 return crypto_shash_alg(tfm)->statesize; 769 } 770 771 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) 772 { 773 return crypto_tfm_get_flags(crypto_shash_tfm(tfm)); 774 } 775 776 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) 777 { 778 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags); 779 } 780 781 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) 782 { 783 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags); 784 } 785 786 /** 787 * crypto_shash_descsize() - obtain the operational state size 788 * @tfm: cipher handle 789 * 790 * The size of the operational state the cipher needs during operation is 791 * returned for the hash referenced with the cipher handle. This size is 792 * required to calculate the memory requirements to allow the caller allocating 793 * sufficient memory for operational state. 794 * 795 * The operational state is defined with struct shash_desc where the size of 796 * that data structure is to be calculated as 797 * sizeof(struct shash_desc) + crypto_shash_descsize(alg) 798 * 799 * Return: size of the operational state 800 */ 801 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) 802 { 803 return tfm->descsize; 804 } 805 806 static inline void *shash_desc_ctx(struct shash_desc *desc) 807 { 808 return desc->__ctx; 809 } 810 811 /** 812 * crypto_shash_setkey() - set key for message digest 813 * @tfm: cipher handle 814 * @key: buffer holding the key 815 * @keylen: length of the key in bytes 816 * 817 * The caller provided key is set for the keyed message digest cipher. The 818 * cipher handle must point to a keyed message digest cipher in order for this 819 * function to succeed. 820 * 821 * Context: Any context. 822 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 823 */ 824 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 825 unsigned int keylen); 826 827 /** 828 * crypto_shash_digest() - calculate message digest for buffer 829 * @desc: see crypto_shash_final() 830 * @data: see crypto_shash_update() 831 * @len: see crypto_shash_update() 832 * @out: see crypto_shash_final() 833 * 834 * This function is a "short-hand" for the function calls of crypto_shash_init, 835 * crypto_shash_update and crypto_shash_final. The parameters have the same 836 * meaning as discussed for those separate three functions. 837 * 838 * Context: Any context. 839 * Return: 0 if the message digest creation was successful; < 0 if an error 840 * occurred 841 */ 842 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 843 unsigned int len, u8 *out); 844 845 /** 846 * crypto_shash_export() - extract operational state for message digest 847 * @desc: reference to the operational state handle whose state is exported 848 * @out: output buffer of sufficient size that can hold the hash state 849 * 850 * This function exports the hash state of the operational state handle into the 851 * caller-allocated output buffer out which must have sufficient size (e.g. by 852 * calling crypto_shash_descsize). 853 * 854 * Context: Any context. 855 * Return: 0 if the export creation was successful; < 0 if an error occurred 856 */ 857 static inline int crypto_shash_export(struct shash_desc *desc, void *out) 858 { 859 return crypto_shash_alg(desc->tfm)->export(desc, out); 860 } 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 static inline int crypto_shash_import(struct shash_desc *desc, const void *in) 875 { 876 struct crypto_shash *tfm = desc->tfm; 877 878 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 879 return -ENOKEY; 880 881 return crypto_shash_alg(tfm)->import(desc, in); 882 } 883 884 /** 885 * crypto_shash_init() - (re)initialize message digest 886 * @desc: operational state handle that is already filled 887 * 888 * The call (re-)initializes the message digest referenced by the 889 * operational state handle. Any potentially existing state created by 890 * previous operations is discarded. 891 * 892 * Context: Any context. 893 * Return: 0 if the message digest initialization was successful; < 0 if an 894 * error occurred 895 */ 896 static inline int crypto_shash_init(struct shash_desc *desc) 897 { 898 struct crypto_shash *tfm = desc->tfm; 899 900 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 901 return -ENOKEY; 902 903 return crypto_shash_alg(tfm)->init(desc); 904 } 905 906 /** 907 * crypto_shash_update() - add data to message digest for processing 908 * @desc: operational state handle that is already initialized 909 * @data: input data to be added to the message digest 910 * @len: length of the input data 911 * 912 * Updates the message digest state of the operational state handle. 913 * 914 * Context: Any context. 915 * Return: 0 if the message digest update was successful; < 0 if an error 916 * occurred 917 */ 918 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 919 unsigned int len); 920 921 /** 922 * crypto_shash_final() - calculate message digest 923 * @desc: operational state handle that is already filled with data 924 * @out: output buffer filled with the message digest 925 * 926 * Finalize the message digest operation and create the message digest 927 * based on all data added to the cipher handle. The message digest is placed 928 * into the output buffer. The caller must ensure that the output buffer is 929 * large enough by using crypto_shash_digestsize. 930 * 931 * Context: Any context. 932 * Return: 0 if the message digest creation was successful; < 0 if an error 933 * occurred 934 */ 935 int crypto_shash_final(struct shash_desc *desc, u8 *out); 936 937 /** 938 * crypto_shash_finup() - calculate message digest of buffer 939 * @desc: see crypto_shash_final() 940 * @data: see crypto_shash_update() 941 * @len: see crypto_shash_update() 942 * @out: see crypto_shash_final() 943 * 944 * This function is a "short-hand" for the function calls of 945 * crypto_shash_update and crypto_shash_final. The parameters have the same 946 * meaning as discussed for those separate functions. 947 * 948 * Context: Any context. 949 * Return: 0 if the message digest creation was successful; < 0 if an error 950 * occurred 951 */ 952 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 953 unsigned int len, u8 *out); 954 955 static inline void shash_desc_zero(struct shash_desc *desc) 956 { 957 memzero_explicit(desc, 958 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 959 } 960 961 #endif /* _CRYPTO_HASH_H */ 962