1 /* SPDX-License-Identifier: GPL-2.0-or-later */ 2 /* 3 * Hash: Hash algorithms under the crypto API 4 * 5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au> 6 */ 7 8 #ifndef _CRYPTO_HASH_H 9 #define _CRYPTO_HASH_H 10 11 #include <linux/atomic.h> 12 #include <linux/crypto.h> 13 #include <linux/string.h> 14 15 struct crypto_ahash; 16 17 /** 18 * DOC: Message Digest Algorithm Definitions 19 * 20 * These data structures define modular message digest algorithm 21 * implementations, managed via crypto_register_ahash(), 22 * crypto_register_shash(), crypto_unregister_ahash() and 23 * crypto_unregister_shash(). 24 */ 25 26 /* 27 * struct crypto_istat_hash - statistics for has algorithm 28 * @hash_cnt: number of hash requests 29 * @hash_tlen: total data size hashed 30 * @err_cnt: number of error for hash requests 31 */ 32 struct crypto_istat_hash { 33 atomic64_t hash_cnt; 34 atomic64_t hash_tlen; 35 atomic64_t err_cnt; 36 }; 37 38 #ifdef CONFIG_CRYPTO_STATS 39 #define HASH_ALG_COMMON_STAT struct crypto_istat_hash stat; 40 #else 41 #define HASH_ALG_COMMON_STAT 42 #endif 43 44 /* 45 * struct hash_alg_common - define properties of message digest 46 * @stat: Statistics for hash algorithm. 47 * @digestsize: Size of the result of the transformation. A buffer of this size 48 * must be available to the @final and @finup calls, so they can 49 * store the resulting hash into it. For various predefined sizes, 50 * search include/crypto/ using 51 * git grep _DIGEST_SIZE include/crypto. 52 * @statesize: Size of the block for partial state of the transformation. A 53 * buffer of this size must be passed to the @export function as it 54 * will save the partial state of the transformation into it. On the 55 * other side, the @import function will load the state from a 56 * buffer of this size as well. 57 * @base: Start of data structure of cipher algorithm. The common data 58 * structure of crypto_alg contains information common to all ciphers. 59 * The hash_alg_common data structure now adds the hash-specific 60 * information. 61 */ 62 #define HASH_ALG_COMMON { \ 63 HASH_ALG_COMMON_STAT \ 64 \ 65 unsigned int digestsize; \ 66 unsigned int statesize; \ 67 \ 68 struct crypto_alg base; \ 69 } 70 struct hash_alg_common HASH_ALG_COMMON; 71 72 struct ahash_request { 73 struct crypto_async_request base; 74 75 unsigned int nbytes; 76 struct scatterlist *src; 77 u8 *result; 78 79 /* This field may only be used by the ahash API code. */ 80 void *priv; 81 82 void *__ctx[] CRYPTO_MINALIGN_ATTR; 83 }; 84 85 /** 86 * struct ahash_alg - asynchronous message digest definition 87 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the 88 * state of the HASH transformation at the beginning. This shall fill in 89 * the internal structures used during the entire duration of the whole 90 * transformation. No data processing happens at this point. Driver code 91 * implementation must not use req->result. 92 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This 93 * function actually pushes blocks of data from upper layers into the 94 * driver, which then passes those to the hardware as seen fit. This 95 * function must not finalize the HASH transformation by calculating the 96 * final message digest as this only adds more data into the 97 * transformation. This function shall not modify the transformation 98 * context, as this function may be called in parallel with the same 99 * transformation object. Data processing can happen synchronously 100 * [SHASH] or asynchronously [AHASH] at this point. Driver must not use 101 * req->result. 102 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the 103 * transformation and retrieves the resulting hash from the driver and 104 * pushes it back to upper layers. No data processing happens at this 105 * point unless hardware requires it to finish the transformation 106 * (then the data buffered by the device driver is processed). 107 * @finup: **[optional]** Combination of @update and @final. This function is effectively a 108 * combination of @update and @final calls issued in sequence. As some 109 * hardware cannot do @update and @final separately, this callback was 110 * added to allow such hardware to be used at least by IPsec. Data 111 * processing can happen synchronously [SHASH] or asynchronously [AHASH] 112 * at this point. 113 * @digest: Combination of @init and @update and @final. This function 114 * effectively behaves as the entire chain of operations, @init, 115 * @update and @final issued in sequence. Just like @finup, this was 116 * added for hardware which cannot do even the @finup, but can only do 117 * the whole transformation in one run. Data processing can happen 118 * synchronously [SHASH] or asynchronously [AHASH] at this point. 119 * @setkey: Set optional key used by the hashing algorithm. Intended to push 120 * optional key used by the hashing algorithm from upper layers into 121 * the driver. This function can store the key in the transformation 122 * context or can outright program it into the hardware. In the former 123 * case, one must be careful to program the key into the hardware at 124 * appropriate time and one must be careful that .setkey() can be 125 * called multiple times during the existence of the transformation 126 * object. Not all hashing algorithms do implement this function as it 127 * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT 128 * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement 129 * this function. This function must be called before any other of the 130 * @init, @update, @final, @finup, @digest is called. No data 131 * processing happens at this point. 132 * @export: Export partial state of the transformation. This function dumps the 133 * entire state of the ongoing transformation into a provided block of 134 * data so it can be @import 'ed back later on. This is useful in case 135 * you want to save partial result of the transformation after 136 * processing certain amount of data and reload this partial result 137 * multiple times later on for multiple re-use. No data processing 138 * happens at this point. Driver must not use req->result. 139 * @import: Import partial state of the transformation. This function loads the 140 * entire state of the ongoing transformation from a provided block of 141 * data so the transformation can continue from this point onward. No 142 * data processing happens at this point. Driver must not use 143 * req->result. 144 * @init_tfm: Initialize the cryptographic transformation object. 145 * This function is called only once at the instantiation 146 * time, right after the transformation context was 147 * allocated. In case the cryptographic hardware has 148 * some special requirements which need to be handled 149 * by software, this function shall check for the precise 150 * requirement of the transformation and put any software 151 * fallbacks in place. 152 * @exit_tfm: Deinitialize the cryptographic transformation object. 153 * This is a counterpart to @init_tfm, used to remove 154 * various changes set in @init_tfm. 155 * @clone_tfm: Copy transform into new object, may allocate memory. 156 * @halg: see struct hash_alg_common 157 */ 158 struct ahash_alg { 159 int (*init)(struct ahash_request *req); 160 int (*update)(struct ahash_request *req); 161 int (*final)(struct ahash_request *req); 162 int (*finup)(struct ahash_request *req); 163 int (*digest)(struct ahash_request *req); 164 int (*export)(struct ahash_request *req, void *out); 165 int (*import)(struct ahash_request *req, const void *in); 166 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 167 unsigned int keylen); 168 int (*init_tfm)(struct crypto_ahash *tfm); 169 void (*exit_tfm)(struct crypto_ahash *tfm); 170 int (*clone_tfm)(struct crypto_ahash *dst, struct crypto_ahash *src); 171 172 struct hash_alg_common halg; 173 }; 174 175 struct shash_desc { 176 struct crypto_shash *tfm; 177 void *__ctx[] __aligned(ARCH_SLAB_MINALIGN); 178 }; 179 180 #define HASH_MAX_DIGESTSIZE 64 181 182 /* 183 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' 184 * containing a 'struct sha3_state'. 185 */ 186 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360) 187 188 #define SHASH_DESC_ON_STACK(shash, ctx) \ 189 char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \ 190 __aligned(__alignof__(struct shash_desc)); \ 191 struct shash_desc *shash = (struct shash_desc *)__##shash##_desc 192 193 /** 194 * struct shash_alg - synchronous message digest definition 195 * @init: see struct ahash_alg 196 * @update: see struct ahash_alg 197 * @final: see struct ahash_alg 198 * @finup: see struct ahash_alg 199 * @digest: see struct ahash_alg 200 * @export: see struct ahash_alg 201 * @import: see struct ahash_alg 202 * @setkey: see struct ahash_alg 203 * @init_tfm: Initialize the cryptographic transformation object. 204 * This function is called only once at the instantiation 205 * time, right after the transformation context was 206 * allocated. In case the cryptographic hardware has 207 * some special requirements which need to be handled 208 * by software, this function shall check for the precise 209 * requirement of the transformation and put any software 210 * fallbacks in place. 211 * @exit_tfm: Deinitialize the cryptographic transformation object. 212 * This is a counterpart to @init_tfm, used to remove 213 * various changes set in @init_tfm. 214 * @clone_tfm: Copy transform into new object, may allocate memory. 215 * @descsize: Size of the operational state for the message digest. This state 216 * size is the memory size that needs to be allocated for 217 * shash_desc.__ctx 218 * @halg: see struct hash_alg_common 219 * @HASH_ALG_COMMON: see struct hash_alg_common 220 */ 221 struct shash_alg { 222 int (*init)(struct shash_desc *desc); 223 int (*update)(struct shash_desc *desc, const u8 *data, 224 unsigned int len); 225 int (*final)(struct shash_desc *desc, u8 *out); 226 int (*finup)(struct shash_desc *desc, const u8 *data, 227 unsigned int len, u8 *out); 228 int (*digest)(struct shash_desc *desc, const u8 *data, 229 unsigned int len, u8 *out); 230 int (*export)(struct shash_desc *desc, void *out); 231 int (*import)(struct shash_desc *desc, const void *in); 232 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 233 unsigned int keylen); 234 int (*init_tfm)(struct crypto_shash *tfm); 235 void (*exit_tfm)(struct crypto_shash *tfm); 236 int (*clone_tfm)(struct crypto_shash *dst, struct crypto_shash *src); 237 238 unsigned int descsize; 239 240 union { 241 struct HASH_ALG_COMMON; 242 struct hash_alg_common halg; 243 }; 244 }; 245 #undef HASH_ALG_COMMON 246 #undef HASH_ALG_COMMON_STAT 247 248 struct crypto_ahash { 249 bool using_shash; /* Underlying algorithm is shash, not ahash */ 250 unsigned int statesize; 251 unsigned int reqsize; 252 struct crypto_tfm base; 253 }; 254 255 struct crypto_shash { 256 unsigned int descsize; 257 struct crypto_tfm base; 258 }; 259 260 /** 261 * DOC: Asynchronous Message Digest API 262 * 263 * The asynchronous message digest API is used with the ciphers of type 264 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 265 * 266 * The asynchronous cipher operation discussion provided for the 267 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well. 268 */ 269 270 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 271 { 272 return container_of(tfm, struct crypto_ahash, base); 273 } 274 275 /** 276 * crypto_alloc_ahash() - allocate ahash cipher handle 277 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 278 * ahash cipher 279 * @type: specifies the type of the cipher 280 * @mask: specifies the mask for the cipher 281 * 282 * Allocate a cipher handle for an ahash. The returned struct 283 * crypto_ahash is the cipher handle that is required for any subsequent 284 * API invocation for that ahash. 285 * 286 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 287 * of an error, PTR_ERR() returns the error code. 288 */ 289 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 290 u32 mask); 291 292 struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *tfm); 293 294 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 295 { 296 return &tfm->base; 297 } 298 299 /** 300 * crypto_free_ahash() - zeroize and free the ahash handle 301 * @tfm: cipher handle to be freed 302 * 303 * If @tfm is a NULL or error pointer, this function does nothing. 304 */ 305 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 306 { 307 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 308 } 309 310 /** 311 * crypto_has_ahash() - Search for the availability of an ahash. 312 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 313 * ahash 314 * @type: specifies the type of the ahash 315 * @mask: specifies the mask for the ahash 316 * 317 * Return: true when the ahash is known to the kernel crypto API; false 318 * otherwise 319 */ 320 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 321 322 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 323 { 324 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 325 } 326 327 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 328 { 329 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 330 } 331 332 /** 333 * crypto_ahash_blocksize() - obtain block size for cipher 334 * @tfm: cipher handle 335 * 336 * The block size for the message digest cipher referenced with the cipher 337 * handle is returned. 338 * 339 * Return: block size of cipher 340 */ 341 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 342 { 343 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 344 } 345 346 static inline struct hash_alg_common *__crypto_hash_alg_common( 347 struct crypto_alg *alg) 348 { 349 return container_of(alg, struct hash_alg_common, base); 350 } 351 352 static inline struct hash_alg_common *crypto_hash_alg_common( 353 struct crypto_ahash *tfm) 354 { 355 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 356 } 357 358 /** 359 * crypto_ahash_digestsize() - obtain message digest size 360 * @tfm: cipher handle 361 * 362 * The size for the message digest created by the message digest cipher 363 * referenced with the cipher handle is returned. 364 * 365 * 366 * Return: message digest size of cipher 367 */ 368 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 369 { 370 return crypto_hash_alg_common(tfm)->digestsize; 371 } 372 373 /** 374 * crypto_ahash_statesize() - obtain size of the ahash state 375 * @tfm: cipher handle 376 * 377 * Return the size of the ahash state. With the crypto_ahash_export() 378 * function, the caller can export the state into a buffer whose size is 379 * defined with this function. 380 * 381 * Return: size of the ahash state 382 */ 383 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 384 { 385 return tfm->statesize; 386 } 387 388 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 389 { 390 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 391 } 392 393 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 394 { 395 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 396 } 397 398 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 399 { 400 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 401 } 402 403 /** 404 * crypto_ahash_reqtfm() - obtain cipher handle from request 405 * @req: asynchronous request handle that contains the reference to the ahash 406 * cipher handle 407 * 408 * Return the ahash cipher handle that is registered with the asynchronous 409 * request handle ahash_request. 410 * 411 * Return: ahash cipher handle 412 */ 413 static inline struct crypto_ahash *crypto_ahash_reqtfm( 414 struct ahash_request *req) 415 { 416 return __crypto_ahash_cast(req->base.tfm); 417 } 418 419 /** 420 * crypto_ahash_reqsize() - obtain size of the request data structure 421 * @tfm: cipher handle 422 * 423 * Return: size of the request data 424 */ 425 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 426 { 427 return tfm->reqsize; 428 } 429 430 static inline void *ahash_request_ctx(struct ahash_request *req) 431 { 432 return req->__ctx; 433 } 434 435 /** 436 * crypto_ahash_setkey - set key for cipher handle 437 * @tfm: cipher handle 438 * @key: buffer holding the key 439 * @keylen: length of the key in bytes 440 * 441 * The caller provided key is set for the ahash cipher. The cipher 442 * handle must point to a keyed hash in order for this function to succeed. 443 * 444 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 445 */ 446 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 447 unsigned int keylen); 448 449 /** 450 * crypto_ahash_finup() - update and finalize message digest 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 455 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 456 * meaning as discussed for those separate functions. 457 * 458 * Return: see crypto_ahash_final() 459 */ 460 int crypto_ahash_finup(struct ahash_request *req); 461 462 /** 463 * crypto_ahash_final() - calculate message digest 464 * @req: reference to the ahash_request handle that holds all information 465 * needed to perform the cipher operation 466 * 467 * Finalize the message digest operation and create the message digest 468 * based on all data added to the cipher handle. The message digest is placed 469 * into the output buffer registered with the ahash_request handle. 470 * 471 * Return: 472 * 0 if the message digest was successfully calculated; 473 * -EINPROGRESS if data is fed into hardware (DMA) or queued for later; 474 * -EBUSY if queue is full and request should be resubmitted later; 475 * other < 0 if an error occurred 476 */ 477 int crypto_ahash_final(struct ahash_request *req); 478 479 /** 480 * crypto_ahash_digest() - calculate message digest for a buffer 481 * @req: reference to the ahash_request handle that holds all information 482 * needed to perform the cipher operation 483 * 484 * This function is a "short-hand" for the function calls of crypto_ahash_init, 485 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 486 * meaning as discussed for those separate three functions. 487 * 488 * Return: see crypto_ahash_final() 489 */ 490 int crypto_ahash_digest(struct ahash_request *req); 491 492 /** 493 * crypto_ahash_export() - extract current message digest state 494 * @req: reference to the ahash_request handle whose state is exported 495 * @out: output buffer of sufficient size that can hold the hash state 496 * 497 * This function exports the hash state of the ahash_request handle into the 498 * caller-allocated output buffer out which must have sufficient size (e.g. by 499 * calling crypto_ahash_statesize()). 500 * 501 * Return: 0 if the export was successful; < 0 if an error occurred 502 */ 503 int crypto_ahash_export(struct ahash_request *req, void *out); 504 505 /** 506 * crypto_ahash_import() - import message digest state 507 * @req: reference to ahash_request handle the state is imported into 508 * @in: buffer holding the state 509 * 510 * This function imports the hash state into the ahash_request handle from the 511 * input buffer. That buffer should have been generated with the 512 * crypto_ahash_export function. 513 * 514 * Return: 0 if the import was successful; < 0 if an error occurred 515 */ 516 int crypto_ahash_import(struct ahash_request *req, const void *in); 517 518 /** 519 * crypto_ahash_init() - (re)initialize message digest handle 520 * @req: ahash_request handle that already is initialized with all necessary 521 * data using the ahash_request_* API functions 522 * 523 * The call (re-)initializes the message digest referenced by the ahash_request 524 * handle. Any potentially existing state created by previous operations is 525 * discarded. 526 * 527 * Return: see crypto_ahash_final() 528 */ 529 int crypto_ahash_init(struct ahash_request *req); 530 531 /** 532 * crypto_ahash_update() - add data to message digest for processing 533 * @req: ahash_request handle that was previously initialized with the 534 * crypto_ahash_init call. 535 * 536 * Updates the message digest state of the &ahash_request handle. The input data 537 * is pointed to by the scatter/gather list registered in the &ahash_request 538 * handle 539 * 540 * Return: see crypto_ahash_final() 541 */ 542 int crypto_ahash_update(struct ahash_request *req); 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 kfree_sensitive(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 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 struct crypto_shash *crypto_clone_shash(struct crypto_shash *tfm); 704 705 int crypto_has_shash(const char *alg_name, u32 type, u32 mask); 706 707 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 708 { 709 return &tfm->base; 710 } 711 712 /** 713 * crypto_free_shash() - zeroize and free the message digest handle 714 * @tfm: cipher handle to be freed 715 * 716 * If @tfm is a NULL or error pointer, this function does nothing. 717 */ 718 static inline void crypto_free_shash(struct crypto_shash *tfm) 719 { 720 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 721 } 722 723 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 724 { 725 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 726 } 727 728 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 729 { 730 return crypto_tfm_alg_driver_name(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_tfm_digest() - calculate message digest for buffer 852 * @tfm: hash transformation object 853 * @data: see crypto_shash_update() 854 * @len: see crypto_shash_update() 855 * @out: see crypto_shash_final() 856 * 857 * This is a simplified version of crypto_shash_digest() for users who don't 858 * want to allocate their own hash descriptor (shash_desc). Instead, 859 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash) 860 * directly, and it allocates a hash descriptor on the stack internally. 861 * Note that this stack allocation may be fairly large. 862 * 863 * Context: Any context. 864 * Return: 0 on success; < 0 if an error occurred. 865 */ 866 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, 867 unsigned int len, u8 *out); 868 869 /** 870 * crypto_shash_export() - extract operational state for message digest 871 * @desc: reference to the operational state handle whose state is exported 872 * @out: output buffer of sufficient size that can hold the hash state 873 * 874 * This function exports the hash state of the operational state handle into the 875 * caller-allocated output buffer out which must have sufficient size (e.g. by 876 * calling crypto_shash_descsize). 877 * 878 * Context: Any context. 879 * Return: 0 if the export creation was successful; < 0 if an error occurred 880 */ 881 int crypto_shash_export(struct shash_desc *desc, void *out); 882 883 /** 884 * crypto_shash_import() - import operational state 885 * @desc: reference to the operational state handle the state imported into 886 * @in: buffer holding the state 887 * 888 * This function imports the hash state into the operational state handle from 889 * the input buffer. That buffer should have been generated with the 890 * crypto_ahash_export function. 891 * 892 * Context: Any context. 893 * Return: 0 if the import was successful; < 0 if an error occurred 894 */ 895 int crypto_shash_import(struct shash_desc *desc, const void *in); 896 897 /** 898 * crypto_shash_init() - (re)initialize message digest 899 * @desc: operational state handle that is already filled 900 * 901 * The call (re-)initializes the message digest referenced by the 902 * operational state handle. Any potentially existing state created by 903 * previous operations is discarded. 904 * 905 * Context: Any context. 906 * Return: 0 if the message digest initialization was successful; < 0 if an 907 * error occurred 908 */ 909 static inline int crypto_shash_init(struct shash_desc *desc) 910 { 911 struct crypto_shash *tfm = desc->tfm; 912 913 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 914 return -ENOKEY; 915 916 return crypto_shash_alg(tfm)->init(desc); 917 } 918 919 /** 920 * crypto_shash_update() - add data to message digest for processing 921 * @desc: operational state handle that is already initialized 922 * @data: input data to be added to the message digest 923 * @len: length of the input data 924 * 925 * Updates the message digest state of the operational state handle. 926 * 927 * Context: Any context. 928 * Return: 0 if the message digest update was successful; < 0 if an error 929 * occurred 930 */ 931 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 932 unsigned int len); 933 934 /** 935 * crypto_shash_final() - calculate message digest 936 * @desc: operational state handle that is already filled with data 937 * @out: output buffer filled with the message digest 938 * 939 * Finalize the message digest operation and create the message digest 940 * based on all data added to the cipher handle. The message digest is placed 941 * into the output buffer. The caller must ensure that the output buffer is 942 * large enough by using crypto_shash_digestsize. 943 * 944 * Context: Any context. 945 * Return: 0 if the message digest creation was successful; < 0 if an error 946 * occurred 947 */ 948 int crypto_shash_final(struct shash_desc *desc, u8 *out); 949 950 /** 951 * crypto_shash_finup() - calculate message digest of buffer 952 * @desc: see crypto_shash_final() 953 * @data: see crypto_shash_update() 954 * @len: see crypto_shash_update() 955 * @out: see crypto_shash_final() 956 * 957 * This function is a "short-hand" for the function calls of 958 * crypto_shash_update and crypto_shash_final. The parameters have the same 959 * meaning as discussed for those separate functions. 960 * 961 * Context: Any context. 962 * Return: 0 if the message digest creation was successful; < 0 if an error 963 * occurred 964 */ 965 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 966 unsigned int len, u8 *out); 967 968 static inline void shash_desc_zero(struct shash_desc *desc) 969 { 970 memzero_explicit(desc, 971 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 972 } 973 974 #endif /* _CRYPTO_HASH_H */ 975