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 u32 flags; 150 151 void *__ctx[] CRYPTO_MINALIGN_ATTR; 152 }; 153 154 #define HASH_MAX_DIGESTSIZE 64 155 #define HASH_MAX_DESCSIZE 360 156 #define HASH_MAX_STATESIZE 512 157 158 #define SHASH_DESC_ON_STACK(shash, ctx) \ 159 char __##shash##_desc[sizeof(struct shash_desc) + \ 160 HASH_MAX_DESCSIZE] CRYPTO_MINALIGN_ATTR; \ 161 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc 162 163 /** 164 * struct shash_alg - synchronous message digest definition 165 * @init: see struct ahash_alg 166 * @update: see struct ahash_alg 167 * @final: see struct ahash_alg 168 * @finup: see struct ahash_alg 169 * @digest: see struct ahash_alg 170 * @export: see struct ahash_alg 171 * @import: see struct ahash_alg 172 * @setkey: see struct ahash_alg 173 * @digestsize: see struct ahash_alg 174 * @statesize: see struct ahash_alg 175 * @descsize: Size of the operational state for the message digest. This state 176 * size is the memory size that needs to be allocated for 177 * shash_desc.__ctx 178 * @base: internally used 179 */ 180 struct shash_alg { 181 int (*init)(struct shash_desc *desc); 182 int (*update)(struct shash_desc *desc, const u8 *data, 183 unsigned int len); 184 int (*final)(struct shash_desc *desc, u8 *out); 185 int (*finup)(struct shash_desc *desc, const u8 *data, 186 unsigned int len, u8 *out); 187 int (*digest)(struct shash_desc *desc, const u8 *data, 188 unsigned int len, u8 *out); 189 int (*export)(struct shash_desc *desc, void *out); 190 int (*import)(struct shash_desc *desc, const void *in); 191 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 192 unsigned int keylen); 193 194 unsigned int descsize; 195 196 /* These fields must match hash_alg_common. */ 197 unsigned int digestsize 198 __attribute__ ((aligned(__alignof__(struct hash_alg_common)))); 199 unsigned int statesize; 200 201 struct crypto_alg base; 202 }; 203 204 struct crypto_ahash { 205 int (*init)(struct ahash_request *req); 206 int (*update)(struct ahash_request *req); 207 int (*final)(struct ahash_request *req); 208 int (*finup)(struct ahash_request *req); 209 int (*digest)(struct ahash_request *req); 210 int (*export)(struct ahash_request *req, void *out); 211 int (*import)(struct ahash_request *req, const void *in); 212 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 213 unsigned int keylen); 214 215 unsigned int reqsize; 216 struct crypto_tfm base; 217 }; 218 219 struct crypto_shash { 220 unsigned int descsize; 221 struct crypto_tfm base; 222 }; 223 224 /** 225 * DOC: Asynchronous Message Digest API 226 * 227 * The asynchronous message digest API is used with the ciphers of type 228 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 229 * 230 * The asynchronous cipher operation discussion provided for the 231 * CRYPTO_ALG_TYPE_ABLKCIPHER API applies here as well. 232 */ 233 234 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 235 { 236 return container_of(tfm, struct crypto_ahash, base); 237 } 238 239 /** 240 * crypto_alloc_ahash() - allocate ahash cipher handle 241 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 242 * ahash cipher 243 * @type: specifies the type of the cipher 244 * @mask: specifies the mask for the cipher 245 * 246 * Allocate a cipher handle for an ahash. The returned struct 247 * crypto_ahash is the cipher handle that is required for any subsequent 248 * API invocation for that ahash. 249 * 250 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 251 * of an error, PTR_ERR() returns the error code. 252 */ 253 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 254 u32 mask); 255 256 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 257 { 258 return &tfm->base; 259 } 260 261 /** 262 * crypto_free_ahash() - zeroize and free the ahash handle 263 * @tfm: cipher handle to be freed 264 */ 265 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 266 { 267 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 268 } 269 270 /** 271 * crypto_has_ahash() - Search for the availability of an ahash. 272 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 273 * ahash 274 * @type: specifies the type of the ahash 275 * @mask: specifies the mask for the ahash 276 * 277 * Return: true when the ahash is known to the kernel crypto API; false 278 * otherwise 279 */ 280 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 281 282 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 283 { 284 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 285 } 286 287 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 288 { 289 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 290 } 291 292 static inline unsigned int crypto_ahash_alignmask( 293 struct crypto_ahash *tfm) 294 { 295 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm)); 296 } 297 298 /** 299 * crypto_ahash_blocksize() - obtain block size for cipher 300 * @tfm: cipher handle 301 * 302 * The block size for the message digest cipher referenced with the cipher 303 * handle is returned. 304 * 305 * Return: block size of cipher 306 */ 307 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 308 { 309 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 310 } 311 312 static inline struct hash_alg_common *__crypto_hash_alg_common( 313 struct crypto_alg *alg) 314 { 315 return container_of(alg, struct hash_alg_common, base); 316 } 317 318 static inline struct hash_alg_common *crypto_hash_alg_common( 319 struct crypto_ahash *tfm) 320 { 321 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 322 } 323 324 /** 325 * crypto_ahash_digestsize() - obtain message digest size 326 * @tfm: cipher handle 327 * 328 * The size for the message digest created by the message digest cipher 329 * referenced with the cipher handle is returned. 330 * 331 * 332 * Return: message digest size of cipher 333 */ 334 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 335 { 336 return crypto_hash_alg_common(tfm)->digestsize; 337 } 338 339 /** 340 * crypto_ahash_statesize() - obtain size of the ahash state 341 * @tfm: cipher handle 342 * 343 * Return the size of the ahash state. With the crypto_ahash_export() 344 * function, the caller can export the state into a buffer whose size is 345 * defined with this function. 346 * 347 * Return: size of the ahash state 348 */ 349 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 350 { 351 return crypto_hash_alg_common(tfm)->statesize; 352 } 353 354 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 355 { 356 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 357 } 358 359 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 360 { 361 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 362 } 363 364 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 365 { 366 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 367 } 368 369 /** 370 * crypto_ahash_reqtfm() - obtain cipher handle from request 371 * @req: asynchronous request handle that contains the reference to the ahash 372 * cipher handle 373 * 374 * Return the ahash cipher handle that is registered with the asynchronous 375 * request handle ahash_request. 376 * 377 * Return: ahash cipher handle 378 */ 379 static inline struct crypto_ahash *crypto_ahash_reqtfm( 380 struct ahash_request *req) 381 { 382 return __crypto_ahash_cast(req->base.tfm); 383 } 384 385 /** 386 * crypto_ahash_reqsize() - obtain size of the request data structure 387 * @tfm: cipher handle 388 * 389 * Return: size of the request data 390 */ 391 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 392 { 393 return tfm->reqsize; 394 } 395 396 static inline void *ahash_request_ctx(struct ahash_request *req) 397 { 398 return req->__ctx; 399 } 400 401 /** 402 * crypto_ahash_setkey - set key for cipher handle 403 * @tfm: cipher handle 404 * @key: buffer holding the key 405 * @keylen: length of the key in bytes 406 * 407 * The caller provided key is set for the ahash cipher. The cipher 408 * handle must point to a keyed hash in order for this function to succeed. 409 * 410 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 411 */ 412 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 413 unsigned int keylen); 414 415 static inline void crypto_stat_ahash_update(struct ahash_request *req, int ret) 416 { 417 #ifdef CONFIG_CRYPTO_STATS 418 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 419 420 if (ret && ret != -EINPROGRESS && ret != -EBUSY) 421 atomic_inc(&tfm->base.__crt_alg->hash_err_cnt); 422 else 423 atomic64_add(req->nbytes, &tfm->base.__crt_alg->hash_tlen); 424 #endif 425 } 426 427 static inline void crypto_stat_ahash_final(struct ahash_request *req, int ret) 428 { 429 #ifdef CONFIG_CRYPTO_STATS 430 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 431 432 if (ret && ret != -EINPROGRESS && ret != -EBUSY) { 433 atomic_inc(&tfm->base.__crt_alg->hash_err_cnt); 434 } else { 435 atomic_inc(&tfm->base.__crt_alg->hash_cnt); 436 atomic64_add(req->nbytes, &tfm->base.__crt_alg->hash_tlen); 437 } 438 #endif 439 } 440 441 /** 442 * crypto_ahash_finup() - update and finalize message digest 443 * @req: reference to the ahash_request handle that holds all information 444 * needed to perform the cipher operation 445 * 446 * This function is a "short-hand" for the function calls of 447 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 448 * meaning as discussed for those separate functions. 449 * 450 * Return: see crypto_ahash_final() 451 */ 452 int crypto_ahash_finup(struct ahash_request *req); 453 454 /** 455 * crypto_ahash_final() - calculate message digest 456 * @req: reference to the ahash_request handle that holds all information 457 * needed to perform the cipher operation 458 * 459 * Finalize the message digest operation and create the message digest 460 * based on all data added to the cipher handle. The message digest is placed 461 * into the output buffer registered with the ahash_request handle. 462 * 463 * Return: 464 * 0 if the message digest was successfully calculated; 465 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later; 466 * -EBUSY if queue is full and request should be resubmitted later; 467 * other < 0 if an error occurred 468 */ 469 int crypto_ahash_final(struct ahash_request *req); 470 471 /** 472 * crypto_ahash_digest() - calculate message digest for a buffer 473 * @req: reference to the ahash_request handle that holds all information 474 * needed to perform the cipher operation 475 * 476 * This function is a "short-hand" for the function calls of crypto_ahash_init, 477 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 478 * meaning as discussed for those separate three functions. 479 * 480 * Return: see crypto_ahash_final() 481 */ 482 int crypto_ahash_digest(struct ahash_request *req); 483 484 /** 485 * crypto_ahash_export() - extract current message digest state 486 * @req: reference to the ahash_request handle whose state is exported 487 * @out: output buffer of sufficient size that can hold the hash state 488 * 489 * This function exports the hash state of the ahash_request handle into the 490 * caller-allocated output buffer out which must have sufficient size (e.g. by 491 * calling crypto_ahash_statesize()). 492 * 493 * Return: 0 if the export was successful; < 0 if an error occurred 494 */ 495 static inline int crypto_ahash_export(struct ahash_request *req, void *out) 496 { 497 return crypto_ahash_reqtfm(req)->export(req, out); 498 } 499 500 /** 501 * crypto_ahash_import() - import message digest state 502 * @req: reference to ahash_request handle the state is imported into 503 * @in: buffer holding the state 504 * 505 * This function imports the hash state into the ahash_request handle from the 506 * input buffer. That buffer should have been generated with the 507 * crypto_ahash_export function. 508 * 509 * Return: 0 if the import was successful; < 0 if an error occurred 510 */ 511 static inline int crypto_ahash_import(struct ahash_request *req, const void *in) 512 { 513 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 514 515 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 516 return -ENOKEY; 517 518 return tfm->import(req, in); 519 } 520 521 /** 522 * crypto_ahash_init() - (re)initialize message digest handle 523 * @req: ahash_request handle that already is initialized with all necessary 524 * data using the ahash_request_* API functions 525 * 526 * The call (re-)initializes the message digest referenced by the ahash_request 527 * handle. Any potentially existing state created by previous operations is 528 * discarded. 529 * 530 * Return: see crypto_ahash_final() 531 */ 532 static inline int crypto_ahash_init(struct ahash_request *req) 533 { 534 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 535 536 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 537 return -ENOKEY; 538 539 return tfm->init(req); 540 } 541 542 /** 543 * crypto_ahash_update() - add data to message digest for processing 544 * @req: ahash_request handle that was previously initialized with the 545 * crypto_ahash_init call. 546 * 547 * Updates the message digest state of the &ahash_request handle. The input data 548 * is pointed to by the scatter/gather list registered in the &ahash_request 549 * handle 550 * 551 * Return: see crypto_ahash_final() 552 */ 553 static inline int crypto_ahash_update(struct ahash_request *req) 554 { 555 int ret; 556 557 ret = crypto_ahash_reqtfm(req)->update(req); 558 crypto_stat_ahash_update(req, ret); 559 return ret; 560 } 561 562 /** 563 * DOC: Asynchronous Hash Request Handle 564 * 565 * The &ahash_request data structure contains all pointers to data 566 * required for the asynchronous cipher operation. This includes the cipher 567 * handle (which can be used by multiple &ahash_request instances), pointer 568 * to plaintext and the message digest output buffer, asynchronous callback 569 * function, etc. It acts as a handle to the ahash_request_* API calls in a 570 * similar way as ahash handle to the crypto_ahash_* API calls. 571 */ 572 573 /** 574 * ahash_request_set_tfm() - update cipher handle reference in request 575 * @req: request handle to be modified 576 * @tfm: cipher handle that shall be added to the request handle 577 * 578 * Allow the caller to replace the existing ahash handle in the request 579 * data structure with a different one. 580 */ 581 static inline void ahash_request_set_tfm(struct ahash_request *req, 582 struct crypto_ahash *tfm) 583 { 584 req->base.tfm = crypto_ahash_tfm(tfm); 585 } 586 587 /** 588 * ahash_request_alloc() - allocate request data structure 589 * @tfm: cipher handle to be registered with the request 590 * @gfp: memory allocation flag that is handed to kmalloc by the API call. 591 * 592 * Allocate the request data structure that must be used with the ahash 593 * message digest API calls. During 594 * the allocation, the provided ahash handle 595 * is registered in the request data structure. 596 * 597 * Return: allocated request handle in case of success, or NULL if out of memory 598 */ 599 static inline struct ahash_request *ahash_request_alloc( 600 struct crypto_ahash *tfm, gfp_t gfp) 601 { 602 struct ahash_request *req; 603 604 req = kmalloc(sizeof(struct ahash_request) + 605 crypto_ahash_reqsize(tfm), gfp); 606 607 if (likely(req)) 608 ahash_request_set_tfm(req, tfm); 609 610 return req; 611 } 612 613 /** 614 * ahash_request_free() - zeroize and free the request data structure 615 * @req: request data structure cipher handle to be freed 616 */ 617 static inline void ahash_request_free(struct ahash_request *req) 618 { 619 kzfree(req); 620 } 621 622 static inline void ahash_request_zero(struct ahash_request *req) 623 { 624 memzero_explicit(req, sizeof(*req) + 625 crypto_ahash_reqsize(crypto_ahash_reqtfm(req))); 626 } 627 628 static inline struct ahash_request *ahash_request_cast( 629 struct crypto_async_request *req) 630 { 631 return container_of(req, struct ahash_request, base); 632 } 633 634 /** 635 * ahash_request_set_callback() - set asynchronous callback function 636 * @req: request handle 637 * @flags: specify zero or an ORing of the flags 638 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and 639 * increase the wait queue beyond the initial maximum size; 640 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep 641 * @compl: callback function pointer to be registered with the request handle 642 * @data: The data pointer refers to memory that is not used by the kernel 643 * crypto API, but provided to the callback function for it to use. Here, 644 * the caller can provide a reference to memory the callback function can 645 * operate on. As the callback function is invoked asynchronously to the 646 * related functionality, it may need to access data structures of the 647 * related functionality which can be referenced using this pointer. The 648 * callback function can access the memory via the "data" field in the 649 * &crypto_async_request data structure provided to the callback function. 650 * 651 * This function allows setting the callback function that is triggered once 652 * the cipher operation completes. 653 * 654 * The callback function is registered with the &ahash_request handle and 655 * must comply with the following template:: 656 * 657 * void callback_function(struct crypto_async_request *req, int error) 658 */ 659 static inline void ahash_request_set_callback(struct ahash_request *req, 660 u32 flags, 661 crypto_completion_t compl, 662 void *data) 663 { 664 req->base.complete = compl; 665 req->base.data = data; 666 req->base.flags = flags; 667 } 668 669 /** 670 * ahash_request_set_crypt() - set data buffers 671 * @req: ahash_request handle to be updated 672 * @src: source scatter/gather list 673 * @result: buffer that is filled with the message digest -- the caller must 674 * ensure that the buffer has sufficient space by, for example, calling 675 * crypto_ahash_digestsize() 676 * @nbytes: number of bytes to process from the source scatter/gather list 677 * 678 * By using this call, the caller references the source scatter/gather list. 679 * The source scatter/gather list points to the data the message digest is to 680 * be calculated for. 681 */ 682 static inline void ahash_request_set_crypt(struct ahash_request *req, 683 struct scatterlist *src, u8 *result, 684 unsigned int nbytes) 685 { 686 req->src = src; 687 req->nbytes = nbytes; 688 req->result = result; 689 } 690 691 /** 692 * DOC: Synchronous Message Digest API 693 * 694 * The synchronous message digest API is used with the ciphers of type 695 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) 696 * 697 * The message digest API is able to maintain state information for the 698 * caller. 699 * 700 * The synchronous message digest API can store user-related context in in its 701 * shash_desc request data structure. 702 */ 703 704 /** 705 * crypto_alloc_shash() - allocate message digest handle 706 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 707 * message digest cipher 708 * @type: specifies the type of the cipher 709 * @mask: specifies the mask for the cipher 710 * 711 * Allocate a cipher handle for a message digest. The returned &struct 712 * crypto_shash is the cipher handle that is required for any subsequent 713 * API invocation for that message digest. 714 * 715 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 716 * of an error, PTR_ERR() returns the error code. 717 */ 718 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 719 u32 mask); 720 721 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 722 { 723 return &tfm->base; 724 } 725 726 /** 727 * crypto_free_shash() - zeroize and free the message digest handle 728 * @tfm: cipher handle to be freed 729 */ 730 static inline void crypto_free_shash(struct crypto_shash *tfm) 731 { 732 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 733 } 734 735 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 736 { 737 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 738 } 739 740 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 741 { 742 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm)); 743 } 744 745 static inline unsigned int crypto_shash_alignmask( 746 struct crypto_shash *tfm) 747 { 748 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm)); 749 } 750 751 /** 752 * crypto_shash_blocksize() - obtain block size for cipher 753 * @tfm: cipher handle 754 * 755 * The block size for the message digest cipher referenced with the cipher 756 * handle is returned. 757 * 758 * Return: block size of cipher 759 */ 760 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) 761 { 762 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm)); 763 } 764 765 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) 766 { 767 return container_of(alg, struct shash_alg, base); 768 } 769 770 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) 771 { 772 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg); 773 } 774 775 /** 776 * crypto_shash_digestsize() - obtain message digest size 777 * @tfm: cipher handle 778 * 779 * The size for the message digest created by the message digest cipher 780 * referenced with the cipher handle is returned. 781 * 782 * Return: digest size of cipher 783 */ 784 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) 785 { 786 return crypto_shash_alg(tfm)->digestsize; 787 } 788 789 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) 790 { 791 return crypto_shash_alg(tfm)->statesize; 792 } 793 794 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) 795 { 796 return crypto_tfm_get_flags(crypto_shash_tfm(tfm)); 797 } 798 799 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) 800 { 801 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags); 802 } 803 804 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) 805 { 806 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags); 807 } 808 809 /** 810 * crypto_shash_descsize() - obtain the operational state size 811 * @tfm: cipher handle 812 * 813 * The size of the operational state the cipher needs during operation is 814 * returned for the hash referenced with the cipher handle. This size is 815 * required to calculate the memory requirements to allow the caller allocating 816 * sufficient memory for operational state. 817 * 818 * The operational state is defined with struct shash_desc where the size of 819 * that data structure is to be calculated as 820 * sizeof(struct shash_desc) + crypto_shash_descsize(alg) 821 * 822 * Return: size of the operational state 823 */ 824 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) 825 { 826 return tfm->descsize; 827 } 828 829 static inline void *shash_desc_ctx(struct shash_desc *desc) 830 { 831 return desc->__ctx; 832 } 833 834 /** 835 * crypto_shash_setkey() - set key for message digest 836 * @tfm: cipher handle 837 * @key: buffer holding the key 838 * @keylen: length of the key in bytes 839 * 840 * The caller provided key is set for the keyed message digest cipher. The 841 * cipher handle must point to a keyed message digest cipher in order for this 842 * function to succeed. 843 * 844 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 845 */ 846 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 847 unsigned int keylen); 848 849 /** 850 * crypto_shash_digest() - calculate message digest for buffer 851 * @desc: see crypto_shash_final() 852 * @data: see crypto_shash_update() 853 * @len: see crypto_shash_update() 854 * @out: see crypto_shash_final() 855 * 856 * This function is a "short-hand" for the function calls of crypto_shash_init, 857 * crypto_shash_update and crypto_shash_final. The parameters have the same 858 * meaning as discussed for those separate three functions. 859 * 860 * Return: 0 if the message digest creation was successful; < 0 if an error 861 * occurred 862 */ 863 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 864 unsigned int len, u8 *out); 865 866 /** 867 * crypto_shash_export() - extract operational state for message digest 868 * @desc: reference to the operational state handle whose state is exported 869 * @out: output buffer of sufficient size that can hold the hash state 870 * 871 * This function exports the hash state of the operational state handle into the 872 * caller-allocated output buffer out which must have sufficient size (e.g. by 873 * calling crypto_shash_descsize). 874 * 875 * Return: 0 if the export creation was successful; < 0 if an error occurred 876 */ 877 static inline int crypto_shash_export(struct shash_desc *desc, void *out) 878 { 879 return crypto_shash_alg(desc->tfm)->export(desc, out); 880 } 881 882 /** 883 * crypto_shash_import() - import operational state 884 * @desc: reference to the operational state handle the state imported into 885 * @in: buffer holding the state 886 * 887 * This function imports the hash state into the operational state handle from 888 * the input buffer. That buffer should have been generated with the 889 * crypto_ahash_export function. 890 * 891 * Return: 0 if the import was successful; < 0 if an error occurred 892 */ 893 static inline int crypto_shash_import(struct shash_desc *desc, const void *in) 894 { 895 struct crypto_shash *tfm = desc->tfm; 896 897 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 898 return -ENOKEY; 899 900 return crypto_shash_alg(tfm)->import(desc, in); 901 } 902 903 /** 904 * crypto_shash_init() - (re)initialize message digest 905 * @desc: operational state handle that is already filled 906 * 907 * The call (re-)initializes the message digest referenced by the 908 * operational state handle. Any potentially existing state created by 909 * previous operations is discarded. 910 * 911 * Return: 0 if the message digest initialization was successful; < 0 if an 912 * error occurred 913 */ 914 static inline int crypto_shash_init(struct shash_desc *desc) 915 { 916 struct crypto_shash *tfm = desc->tfm; 917 918 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 919 return -ENOKEY; 920 921 return crypto_shash_alg(tfm)->init(desc); 922 } 923 924 /** 925 * crypto_shash_update() - add data to message digest for processing 926 * @desc: operational state handle that is already initialized 927 * @data: input data to be added to the message digest 928 * @len: length of the input data 929 * 930 * Updates the message digest state of the operational state handle. 931 * 932 * Return: 0 if the message digest update was successful; < 0 if an error 933 * occurred 934 */ 935 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 936 unsigned int len); 937 938 /** 939 * crypto_shash_final() - calculate message digest 940 * @desc: operational state handle that is already filled with data 941 * @out: output buffer filled with the message digest 942 * 943 * Finalize the message digest operation and create the message digest 944 * based on all data added to the cipher handle. The message digest is placed 945 * into the output buffer. The caller must ensure that the output buffer is 946 * large enough by using crypto_shash_digestsize. 947 * 948 * Return: 0 if the message digest creation was successful; < 0 if an error 949 * occurred 950 */ 951 int crypto_shash_final(struct shash_desc *desc, u8 *out); 952 953 /** 954 * crypto_shash_finup() - calculate message digest of buffer 955 * @desc: see crypto_shash_final() 956 * @data: see crypto_shash_update() 957 * @len: see crypto_shash_update() 958 * @out: see crypto_shash_final() 959 * 960 * This function is a "short-hand" for the function calls of 961 * crypto_shash_update and crypto_shash_final. The parameters have the same 962 * meaning as discussed for those separate functions. 963 * 964 * Return: 0 if the message digest creation was successful; < 0 if an error 965 * occurred 966 */ 967 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 968 unsigned int len, u8 *out); 969 970 static inline void shash_desc_zero(struct shash_desc *desc) 971 { 972 memzero_explicit(desc, 973 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 974 } 975 976 #endif /* _CRYPTO_HASH_H */ 977