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 * @halg: see struct hash_alg_common 156 */ 157 struct ahash_alg { 158 int (*init)(struct ahash_request *req); 159 int (*update)(struct ahash_request *req); 160 int (*final)(struct ahash_request *req); 161 int (*finup)(struct ahash_request *req); 162 int (*digest)(struct ahash_request *req); 163 int (*export)(struct ahash_request *req, void *out); 164 int (*import)(struct ahash_request *req, const void *in); 165 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 166 unsigned int keylen); 167 int (*init_tfm)(struct crypto_ahash *tfm); 168 void (*exit_tfm)(struct crypto_ahash *tfm); 169 170 struct hash_alg_common halg; 171 }; 172 173 struct shash_desc { 174 struct crypto_shash *tfm; 175 void *__ctx[] __aligned(ARCH_SLAB_MINALIGN); 176 }; 177 178 #define HASH_MAX_DIGESTSIZE 64 179 180 /* 181 * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' 182 * containing a 'struct sha3_state'. 183 */ 184 #define HASH_MAX_DESCSIZE (sizeof(struct shash_desc) + 360) 185 186 #define HASH_MAX_STATESIZE 512 187 188 #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 * @digestsize: see struct ahash_alg 215 * @statesize: see struct ahash_alg 216 * @descsize: Size of the operational state for the message digest. This state 217 * size is the memory size that needs to be allocated for 218 * shash_desc.__ctx 219 * @stat: Statistics for hash algorithm. 220 * @base: internally used 221 * @halg: see struct hash_alg_common 222 * @HASH_ALG_COMMON: see struct hash_alg_common 223 */ 224 struct shash_alg { 225 int (*init)(struct shash_desc *desc); 226 int (*update)(struct shash_desc *desc, const u8 *data, 227 unsigned int len); 228 int (*final)(struct shash_desc *desc, u8 *out); 229 int (*finup)(struct shash_desc *desc, const u8 *data, 230 unsigned int len, u8 *out); 231 int (*digest)(struct shash_desc *desc, const u8 *data, 232 unsigned int len, u8 *out); 233 int (*export)(struct shash_desc *desc, void *out); 234 int (*import)(struct shash_desc *desc, const void *in); 235 int (*setkey)(struct crypto_shash *tfm, const u8 *key, 236 unsigned int keylen); 237 int (*init_tfm)(struct crypto_shash *tfm); 238 void (*exit_tfm)(struct crypto_shash *tfm); 239 240 unsigned int descsize; 241 242 union { 243 struct HASH_ALG_COMMON; 244 struct hash_alg_common halg; 245 }; 246 }; 247 #undef HASH_ALG_COMMON 248 #undef HASH_ALG_COMMON_STAT 249 250 struct crypto_ahash { 251 int (*init)(struct ahash_request *req); 252 int (*update)(struct ahash_request *req); 253 int (*final)(struct ahash_request *req); 254 int (*finup)(struct ahash_request *req); 255 int (*digest)(struct ahash_request *req); 256 int (*export)(struct ahash_request *req, void *out); 257 int (*import)(struct ahash_request *req, const void *in); 258 int (*setkey)(struct crypto_ahash *tfm, const u8 *key, 259 unsigned int keylen); 260 261 unsigned int reqsize; 262 struct crypto_tfm base; 263 }; 264 265 struct crypto_shash { 266 unsigned int descsize; 267 struct crypto_tfm base; 268 }; 269 270 /** 271 * DOC: Asynchronous Message Digest API 272 * 273 * The asynchronous message digest API is used with the ciphers of type 274 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) 275 * 276 * The asynchronous cipher operation discussion provided for the 277 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well. 278 */ 279 280 static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) 281 { 282 return container_of(tfm, struct crypto_ahash, base); 283 } 284 285 /** 286 * crypto_alloc_ahash() - allocate ahash cipher handle 287 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 288 * ahash cipher 289 * @type: specifies the type of the cipher 290 * @mask: specifies the mask for the cipher 291 * 292 * Allocate a cipher handle for an ahash. The returned struct 293 * crypto_ahash is the cipher handle that is required for any subsequent 294 * API invocation for that ahash. 295 * 296 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 297 * of an error, PTR_ERR() returns the error code. 298 */ 299 struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, 300 u32 mask); 301 302 static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) 303 { 304 return &tfm->base; 305 } 306 307 /** 308 * crypto_free_ahash() - zeroize and free the ahash handle 309 * @tfm: cipher handle to be freed 310 * 311 * If @tfm is a NULL or error pointer, this function does nothing. 312 */ 313 static inline void crypto_free_ahash(struct crypto_ahash *tfm) 314 { 315 crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm)); 316 } 317 318 /** 319 * crypto_has_ahash() - Search for the availability of an ahash. 320 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 321 * ahash 322 * @type: specifies the type of the ahash 323 * @mask: specifies the mask for the ahash 324 * 325 * Return: true when the ahash is known to the kernel crypto API; false 326 * otherwise 327 */ 328 int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); 329 330 static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) 331 { 332 return crypto_tfm_alg_name(crypto_ahash_tfm(tfm)); 333 } 334 335 static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) 336 { 337 return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm)); 338 } 339 340 static inline unsigned int crypto_ahash_alignmask( 341 struct crypto_ahash *tfm) 342 { 343 return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm)); 344 } 345 346 /** 347 * crypto_ahash_blocksize() - obtain block size for cipher 348 * @tfm: cipher handle 349 * 350 * The block size for the message digest cipher referenced with the cipher 351 * handle is returned. 352 * 353 * Return: block size of cipher 354 */ 355 static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) 356 { 357 return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm)); 358 } 359 360 static inline struct hash_alg_common *__crypto_hash_alg_common( 361 struct crypto_alg *alg) 362 { 363 return container_of(alg, struct hash_alg_common, base); 364 } 365 366 static inline struct hash_alg_common *crypto_hash_alg_common( 367 struct crypto_ahash *tfm) 368 { 369 return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg); 370 } 371 372 /** 373 * crypto_ahash_digestsize() - obtain message digest size 374 * @tfm: cipher handle 375 * 376 * The size for the message digest created by the message digest cipher 377 * referenced with the cipher handle is returned. 378 * 379 * 380 * Return: message digest size of cipher 381 */ 382 static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) 383 { 384 return crypto_hash_alg_common(tfm)->digestsize; 385 } 386 387 /** 388 * crypto_ahash_statesize() - obtain size of the ahash state 389 * @tfm: cipher handle 390 * 391 * Return the size of the ahash state. With the crypto_ahash_export() 392 * function, the caller can export the state into a buffer whose size is 393 * defined with this function. 394 * 395 * Return: size of the ahash state 396 */ 397 static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) 398 { 399 return crypto_hash_alg_common(tfm)->statesize; 400 } 401 402 static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) 403 { 404 return crypto_tfm_get_flags(crypto_ahash_tfm(tfm)); 405 } 406 407 static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) 408 { 409 crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags); 410 } 411 412 static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) 413 { 414 crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags); 415 } 416 417 /** 418 * crypto_ahash_reqtfm() - obtain cipher handle from request 419 * @req: asynchronous request handle that contains the reference to the ahash 420 * cipher handle 421 * 422 * Return the ahash cipher handle that is registered with the asynchronous 423 * request handle ahash_request. 424 * 425 * Return: ahash cipher handle 426 */ 427 static inline struct crypto_ahash *crypto_ahash_reqtfm( 428 struct ahash_request *req) 429 { 430 return __crypto_ahash_cast(req->base.tfm); 431 } 432 433 /** 434 * crypto_ahash_reqsize() - obtain size of the request data structure 435 * @tfm: cipher handle 436 * 437 * Return: size of the request data 438 */ 439 static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) 440 { 441 return tfm->reqsize; 442 } 443 444 static inline void *ahash_request_ctx(struct ahash_request *req) 445 { 446 return req->__ctx; 447 } 448 449 /** 450 * crypto_ahash_setkey - set key for cipher handle 451 * @tfm: cipher handle 452 * @key: buffer holding the key 453 * @keylen: length of the key in bytes 454 * 455 * The caller provided key is set for the ahash cipher. The cipher 456 * handle must point to a keyed hash in order for this function to succeed. 457 * 458 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 459 */ 460 int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, 461 unsigned int keylen); 462 463 /** 464 * crypto_ahash_finup() - update and finalize message digest 465 * @req: reference to the ahash_request handle that holds all information 466 * needed to perform the cipher operation 467 * 468 * This function is a "short-hand" for the function calls of 469 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 470 * meaning as discussed for those separate functions. 471 * 472 * Return: see crypto_ahash_final() 473 */ 474 int crypto_ahash_finup(struct ahash_request *req); 475 476 /** 477 * crypto_ahash_final() - calculate message digest 478 * @req: reference to the ahash_request handle that holds all information 479 * needed to perform the cipher operation 480 * 481 * Finalize the message digest operation and create the message digest 482 * based on all data added to the cipher handle. The message digest is placed 483 * into the output buffer registered with the ahash_request handle. 484 * 485 * Return: 486 * 0 if the message digest was successfully calculated; 487 * -EINPROGRESS if data is fed into hardware (DMA) or queued for later; 488 * -EBUSY if queue is full and request should be resubmitted later; 489 * other < 0 if an error occurred 490 */ 491 int crypto_ahash_final(struct ahash_request *req); 492 493 /** 494 * crypto_ahash_digest() - calculate message digest for a buffer 495 * @req: reference to the ahash_request handle that holds all information 496 * needed to perform the cipher operation 497 * 498 * This function is a "short-hand" for the function calls of crypto_ahash_init, 499 * crypto_ahash_update and crypto_ahash_final. The parameters have the same 500 * meaning as discussed for those separate three functions. 501 * 502 * Return: see crypto_ahash_final() 503 */ 504 int crypto_ahash_digest(struct ahash_request *req); 505 506 /** 507 * crypto_ahash_export() - extract current message digest state 508 * @req: reference to the ahash_request handle whose state is exported 509 * @out: output buffer of sufficient size that can hold the hash state 510 * 511 * This function exports the hash state of the ahash_request handle into the 512 * caller-allocated output buffer out which must have sufficient size (e.g. by 513 * calling crypto_ahash_statesize()). 514 * 515 * Return: 0 if the export was successful; < 0 if an error occurred 516 */ 517 static inline int crypto_ahash_export(struct ahash_request *req, void *out) 518 { 519 return crypto_ahash_reqtfm(req)->export(req, out); 520 } 521 522 /** 523 * crypto_ahash_import() - import message digest state 524 * @req: reference to ahash_request handle the state is imported into 525 * @in: buffer holding the state 526 * 527 * This function imports the hash state into the ahash_request handle from the 528 * input buffer. That buffer should have been generated with the 529 * crypto_ahash_export function. 530 * 531 * Return: 0 if the import was successful; < 0 if an error occurred 532 */ 533 static inline int crypto_ahash_import(struct ahash_request *req, const void *in) 534 { 535 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 536 537 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 538 return -ENOKEY; 539 540 return tfm->import(req, in); 541 } 542 543 /** 544 * crypto_ahash_init() - (re)initialize message digest handle 545 * @req: ahash_request handle that already is initialized with all necessary 546 * data using the ahash_request_* API functions 547 * 548 * The call (re-)initializes the message digest referenced by the ahash_request 549 * handle. Any potentially existing state created by previous operations is 550 * discarded. 551 * 552 * Return: see crypto_ahash_final() 553 */ 554 static inline int crypto_ahash_init(struct ahash_request *req) 555 { 556 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 557 558 if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 559 return -ENOKEY; 560 561 return tfm->init(req); 562 } 563 564 static inline struct crypto_istat_hash *hash_get_stat( 565 struct hash_alg_common *alg) 566 { 567 #ifdef CONFIG_CRYPTO_STATS 568 return &alg->stat; 569 #else 570 return NULL; 571 #endif 572 } 573 574 static inline int crypto_hash_errstat(struct hash_alg_common *alg, int err) 575 { 576 if (!IS_ENABLED(CONFIG_CRYPTO_STATS)) 577 return err; 578 579 if (err && err != -EINPROGRESS && err != -EBUSY) 580 atomic64_inc(&hash_get_stat(alg)->err_cnt); 581 582 return err; 583 } 584 585 /** 586 * crypto_ahash_update() - add data to message digest for processing 587 * @req: ahash_request handle that was previously initialized with the 588 * crypto_ahash_init call. 589 * 590 * Updates the message digest state of the &ahash_request handle. The input data 591 * is pointed to by the scatter/gather list registered in the &ahash_request 592 * handle 593 * 594 * Return: see crypto_ahash_final() 595 */ 596 static inline int crypto_ahash_update(struct ahash_request *req) 597 { 598 struct crypto_ahash *tfm = crypto_ahash_reqtfm(req); 599 struct hash_alg_common *alg = crypto_hash_alg_common(tfm); 600 601 if (IS_ENABLED(CONFIG_CRYPTO_STATS)) 602 atomic64_add(req->nbytes, &hash_get_stat(alg)->hash_tlen); 603 604 return crypto_hash_errstat(alg, tfm->update(req)); 605 } 606 607 /** 608 * DOC: Asynchronous Hash Request Handle 609 * 610 * The &ahash_request data structure contains all pointers to data 611 * required for the asynchronous cipher operation. This includes the cipher 612 * handle (which can be used by multiple &ahash_request instances), pointer 613 * to plaintext and the message digest output buffer, asynchronous callback 614 * function, etc. It acts as a handle to the ahash_request_* API calls in a 615 * similar way as ahash handle to the crypto_ahash_* API calls. 616 */ 617 618 /** 619 * ahash_request_set_tfm() - update cipher handle reference in request 620 * @req: request handle to be modified 621 * @tfm: cipher handle that shall be added to the request handle 622 * 623 * Allow the caller to replace the existing ahash handle in the request 624 * data structure with a different one. 625 */ 626 static inline void ahash_request_set_tfm(struct ahash_request *req, 627 struct crypto_ahash *tfm) 628 { 629 req->base.tfm = crypto_ahash_tfm(tfm); 630 } 631 632 /** 633 * ahash_request_alloc() - allocate request data structure 634 * @tfm: cipher handle to be registered with the request 635 * @gfp: memory allocation flag that is handed to kmalloc by the API call. 636 * 637 * Allocate the request data structure that must be used with the ahash 638 * message digest API calls. During 639 * the allocation, the provided ahash handle 640 * is registered in the request data structure. 641 * 642 * Return: allocated request handle in case of success, or NULL if out of memory 643 */ 644 static inline struct ahash_request *ahash_request_alloc( 645 struct crypto_ahash *tfm, gfp_t gfp) 646 { 647 struct ahash_request *req; 648 649 req = kmalloc(sizeof(struct ahash_request) + 650 crypto_ahash_reqsize(tfm), gfp); 651 652 if (likely(req)) 653 ahash_request_set_tfm(req, tfm); 654 655 return req; 656 } 657 658 /** 659 * ahash_request_free() - zeroize and free the request data structure 660 * @req: request data structure cipher handle to be freed 661 */ 662 static inline void ahash_request_free(struct ahash_request *req) 663 { 664 kfree_sensitive(req); 665 } 666 667 static inline void ahash_request_zero(struct ahash_request *req) 668 { 669 memzero_explicit(req, sizeof(*req) + 670 crypto_ahash_reqsize(crypto_ahash_reqtfm(req))); 671 } 672 673 static inline struct ahash_request *ahash_request_cast( 674 struct crypto_async_request *req) 675 { 676 return container_of(req, struct ahash_request, base); 677 } 678 679 /** 680 * ahash_request_set_callback() - set asynchronous callback function 681 * @req: request handle 682 * @flags: specify zero or an ORing of the flags 683 * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and 684 * increase the wait queue beyond the initial maximum size; 685 * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep 686 * @compl: callback function pointer to be registered with the request handle 687 * @data: The data pointer refers to memory that is not used by the kernel 688 * crypto API, but provided to the callback function for it to use. Here, 689 * the caller can provide a reference to memory the callback function can 690 * operate on. As the callback function is invoked asynchronously to the 691 * related functionality, it may need to access data structures of the 692 * related functionality which can be referenced using this pointer. The 693 * callback function can access the memory via the "data" field in the 694 * &crypto_async_request data structure provided to the callback function. 695 * 696 * This function allows setting the callback function that is triggered once 697 * the cipher operation completes. 698 * 699 * The callback function is registered with the &ahash_request handle and 700 * must comply with the following template:: 701 * 702 * void callback_function(struct crypto_async_request *req, int error) 703 */ 704 static inline void ahash_request_set_callback(struct ahash_request *req, 705 u32 flags, 706 crypto_completion_t compl, 707 void *data) 708 { 709 req->base.complete = compl; 710 req->base.data = data; 711 req->base.flags = flags; 712 } 713 714 /** 715 * ahash_request_set_crypt() - set data buffers 716 * @req: ahash_request handle to be updated 717 * @src: source scatter/gather list 718 * @result: buffer that is filled with the message digest -- the caller must 719 * ensure that the buffer has sufficient space by, for example, calling 720 * crypto_ahash_digestsize() 721 * @nbytes: number of bytes to process from the source scatter/gather list 722 * 723 * By using this call, the caller references the source scatter/gather list. 724 * The source scatter/gather list points to the data the message digest is to 725 * be calculated for. 726 */ 727 static inline void ahash_request_set_crypt(struct ahash_request *req, 728 struct scatterlist *src, u8 *result, 729 unsigned int nbytes) 730 { 731 req->src = src; 732 req->nbytes = nbytes; 733 req->result = result; 734 } 735 736 /** 737 * DOC: Synchronous Message Digest API 738 * 739 * The synchronous message digest API is used with the ciphers of type 740 * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) 741 * 742 * The message digest API is able to maintain state information for the 743 * caller. 744 * 745 * The synchronous message digest API can store user-related context in its 746 * shash_desc request data structure. 747 */ 748 749 /** 750 * crypto_alloc_shash() - allocate message digest handle 751 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the 752 * message digest cipher 753 * @type: specifies the type of the cipher 754 * @mask: specifies the mask for the cipher 755 * 756 * Allocate a cipher handle for a message digest. The returned &struct 757 * crypto_shash is the cipher handle that is required for any subsequent 758 * API invocation for that message digest. 759 * 760 * Return: allocated cipher handle in case of success; IS_ERR() is true in case 761 * of an error, PTR_ERR() returns the error code. 762 */ 763 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, 764 u32 mask); 765 766 int crypto_has_shash(const char *alg_name, u32 type, u32 mask); 767 768 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) 769 { 770 return &tfm->base; 771 } 772 773 /** 774 * crypto_free_shash() - zeroize and free the message digest handle 775 * @tfm: cipher handle to be freed 776 * 777 * If @tfm is a NULL or error pointer, this function does nothing. 778 */ 779 static inline void crypto_free_shash(struct crypto_shash *tfm) 780 { 781 crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm)); 782 } 783 784 static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) 785 { 786 return crypto_tfm_alg_name(crypto_shash_tfm(tfm)); 787 } 788 789 static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) 790 { 791 return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm)); 792 } 793 794 static inline unsigned int crypto_shash_alignmask( 795 struct crypto_shash *tfm) 796 { 797 return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm)); 798 } 799 800 /** 801 * crypto_shash_blocksize() - obtain block size for cipher 802 * @tfm: cipher handle 803 * 804 * The block size for the message digest cipher referenced with the cipher 805 * handle is returned. 806 * 807 * Return: block size of cipher 808 */ 809 static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) 810 { 811 return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm)); 812 } 813 814 static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) 815 { 816 return container_of(alg, struct shash_alg, base); 817 } 818 819 static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) 820 { 821 return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg); 822 } 823 824 /** 825 * crypto_shash_digestsize() - obtain message digest size 826 * @tfm: cipher handle 827 * 828 * The size for the message digest created by the message digest cipher 829 * referenced with the cipher handle is returned. 830 * 831 * Return: digest size of cipher 832 */ 833 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) 834 { 835 return crypto_shash_alg(tfm)->digestsize; 836 } 837 838 static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) 839 { 840 return crypto_shash_alg(tfm)->statesize; 841 } 842 843 static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) 844 { 845 return crypto_tfm_get_flags(crypto_shash_tfm(tfm)); 846 } 847 848 static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) 849 { 850 crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags); 851 } 852 853 static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) 854 { 855 crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags); 856 } 857 858 /** 859 * crypto_shash_descsize() - obtain the operational state size 860 * @tfm: cipher handle 861 * 862 * The size of the operational state the cipher needs during operation is 863 * returned for the hash referenced with the cipher handle. This size is 864 * required to calculate the memory requirements to allow the caller allocating 865 * sufficient memory for operational state. 866 * 867 * The operational state is defined with struct shash_desc where the size of 868 * that data structure is to be calculated as 869 * sizeof(struct shash_desc) + crypto_shash_descsize(alg) 870 * 871 * Return: size of the operational state 872 */ 873 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) 874 { 875 return tfm->descsize; 876 } 877 878 static inline void *shash_desc_ctx(struct shash_desc *desc) 879 { 880 return desc->__ctx; 881 } 882 883 /** 884 * crypto_shash_setkey() - set key for message digest 885 * @tfm: cipher handle 886 * @key: buffer holding the key 887 * @keylen: length of the key in bytes 888 * 889 * The caller provided key is set for the keyed message digest cipher. The 890 * cipher handle must point to a keyed message digest cipher in order for this 891 * function to succeed. 892 * 893 * Context: Any context. 894 * Return: 0 if the setting of the key was successful; < 0 if an error occurred 895 */ 896 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, 897 unsigned int keylen); 898 899 /** 900 * crypto_shash_digest() - calculate message digest for buffer 901 * @desc: see crypto_shash_final() 902 * @data: see crypto_shash_update() 903 * @len: see crypto_shash_update() 904 * @out: see crypto_shash_final() 905 * 906 * This function is a "short-hand" for the function calls of crypto_shash_init, 907 * crypto_shash_update and crypto_shash_final. The parameters have the same 908 * meaning as discussed for those separate three functions. 909 * 910 * Context: Any context. 911 * Return: 0 if the message digest creation was successful; < 0 if an error 912 * occurred 913 */ 914 int crypto_shash_digest(struct shash_desc *desc, const u8 *data, 915 unsigned int len, u8 *out); 916 917 /** 918 * crypto_shash_tfm_digest() - calculate message digest for buffer 919 * @tfm: hash transformation object 920 * @data: see crypto_shash_update() 921 * @len: see crypto_shash_update() 922 * @out: see crypto_shash_final() 923 * 924 * This is a simplified version of crypto_shash_digest() for users who don't 925 * want to allocate their own hash descriptor (shash_desc). Instead, 926 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash) 927 * directly, and it allocates a hash descriptor on the stack internally. 928 * Note that this stack allocation may be fairly large. 929 * 930 * Context: Any context. 931 * Return: 0 on success; < 0 if an error occurred. 932 */ 933 int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, 934 unsigned int len, u8 *out); 935 936 /** 937 * crypto_shash_export() - extract operational state for message digest 938 * @desc: reference to the operational state handle whose state is exported 939 * @out: output buffer of sufficient size that can hold the hash state 940 * 941 * This function exports the hash state of the operational state handle into the 942 * caller-allocated output buffer out which must have sufficient size (e.g. by 943 * calling crypto_shash_descsize). 944 * 945 * Context: Any context. 946 * Return: 0 if the export creation was successful; < 0 if an error occurred 947 */ 948 static inline int crypto_shash_export(struct shash_desc *desc, void *out) 949 { 950 return crypto_shash_alg(desc->tfm)->export(desc, out); 951 } 952 953 /** 954 * crypto_shash_import() - import operational state 955 * @desc: reference to the operational state handle the state imported into 956 * @in: buffer holding the state 957 * 958 * This function imports the hash state into the operational state handle from 959 * the input buffer. That buffer should have been generated with the 960 * crypto_ahash_export function. 961 * 962 * Context: Any context. 963 * Return: 0 if the import was successful; < 0 if an error occurred 964 */ 965 static inline int crypto_shash_import(struct shash_desc *desc, const void *in) 966 { 967 struct crypto_shash *tfm = desc->tfm; 968 969 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 970 return -ENOKEY; 971 972 return crypto_shash_alg(tfm)->import(desc, in); 973 } 974 975 /** 976 * crypto_shash_init() - (re)initialize message digest 977 * @desc: operational state handle that is already filled 978 * 979 * The call (re-)initializes the message digest referenced by the 980 * operational state handle. Any potentially existing state created by 981 * previous operations is discarded. 982 * 983 * Context: Any context. 984 * Return: 0 if the message digest initialization was successful; < 0 if an 985 * error occurred 986 */ 987 static inline int crypto_shash_init(struct shash_desc *desc) 988 { 989 struct crypto_shash *tfm = desc->tfm; 990 991 if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY) 992 return -ENOKEY; 993 994 return crypto_shash_alg(tfm)->init(desc); 995 } 996 997 /** 998 * crypto_shash_update() - add data to message digest for processing 999 * @desc: operational state handle that is already initialized 1000 * @data: input data to be added to the message digest 1001 * @len: length of the input data 1002 * 1003 * Updates the message digest state of the operational state handle. 1004 * 1005 * Context: Any context. 1006 * Return: 0 if the message digest update was successful; < 0 if an error 1007 * occurred 1008 */ 1009 int crypto_shash_update(struct shash_desc *desc, const u8 *data, 1010 unsigned int len); 1011 1012 /** 1013 * crypto_shash_final() - calculate message digest 1014 * @desc: operational state handle that is already filled with data 1015 * @out: output buffer filled with the message digest 1016 * 1017 * Finalize the message digest operation and create the message digest 1018 * based on all data added to the cipher handle. The message digest is placed 1019 * into the output buffer. The caller must ensure that the output buffer is 1020 * large enough by using crypto_shash_digestsize. 1021 * 1022 * Context: Any context. 1023 * Return: 0 if the message digest creation was successful; < 0 if an error 1024 * occurred 1025 */ 1026 int crypto_shash_final(struct shash_desc *desc, u8 *out); 1027 1028 /** 1029 * crypto_shash_finup() - calculate message digest of buffer 1030 * @desc: see crypto_shash_final() 1031 * @data: see crypto_shash_update() 1032 * @len: see crypto_shash_update() 1033 * @out: see crypto_shash_final() 1034 * 1035 * This function is a "short-hand" for the function calls of 1036 * crypto_shash_update and crypto_shash_final. The parameters have the same 1037 * meaning as discussed for those separate functions. 1038 * 1039 * Context: Any context. 1040 * Return: 0 if the message digest creation was successful; < 0 if an error 1041 * occurred 1042 */ 1043 int crypto_shash_finup(struct shash_desc *desc, const u8 *data, 1044 unsigned int len, u8 *out); 1045 1046 static inline void shash_desc_zero(struct shash_desc *desc) 1047 { 1048 memzero_explicit(desc, 1049 sizeof(*desc) + crypto_shash_descsize(desc->tfm)); 1050 } 1051 1052 #endif /* _CRYPTO_HASH_H */ 1053