linux/include/crypto/hash.h
<<
>>
Prefs
   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 * Hash: Hash algorithms under the crypto API
   4 * 
   5 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
   6 */
   7
   8#ifndef _CRYPTO_HASH_H
   9#define _CRYPTO_HASH_H
  10
  11#include <linux/crypto.h>
  12#include <linux/string.h>
  13
  14struct crypto_ahash;
  15
  16/**
  17 * DOC: Message Digest Algorithm Definitions
  18 *
  19 * These data structures define modular message digest algorithm
  20 * implementations, managed via crypto_register_ahash(),
  21 * crypto_register_shash(), crypto_unregister_ahash() and
  22 * crypto_unregister_shash().
  23 */
  24
  25/**
  26 * struct hash_alg_common - define properties of message digest
  27 * @digestsize: Size of the result of the transformation. A buffer of this size
  28 *              must be available to the @final and @finup calls, so they can
  29 *              store the resulting hash into it. For various predefined sizes,
  30 *              search include/crypto/ using
  31 *              git grep _DIGEST_SIZE include/crypto.
  32 * @statesize: Size of the block for partial state of the transformation. A
  33 *             buffer of this size must be passed to the @export function as it
  34 *             will save the partial state of the transformation into it. On the
  35 *             other side, the @import function will load the state from a
  36 *             buffer of this size as well.
  37 * @base: Start of data structure of cipher algorithm. The common data
  38 *        structure of crypto_alg contains information common to all ciphers.
  39 *        The hash_alg_common data structure now adds the hash-specific
  40 *        information.
  41 */
  42struct hash_alg_common {
  43        unsigned int digestsize;
  44        unsigned int statesize;
  45
  46        struct crypto_alg base;
  47};
  48
  49struct ahash_request {
  50        struct crypto_async_request base;
  51
  52        unsigned int nbytes;
  53        struct scatterlist *src;
  54        u8 *result;
  55
  56        /* This field may only be used by the ahash API code. */
  57        void *priv;
  58
  59        void *__ctx[] CRYPTO_MINALIGN_ATTR;
  60};
  61
  62/**
  63 * struct ahash_alg - asynchronous message digest definition
  64 * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the
  65 *        state of the HASH transformation at the beginning. This shall fill in
  66 *        the internal structures used during the entire duration of the whole
  67 *        transformation. No data processing happens at this point. Driver code
  68 *        implementation must not use req->result.
  69 * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This
  70 *         function actually pushes blocks of data from upper layers into the
  71 *         driver, which then passes those to the hardware as seen fit. This
  72 *         function must not finalize the HASH transformation by calculating the
  73 *         final message digest as this only adds more data into the
  74 *         transformation. This function shall not modify the transformation
  75 *         context, as this function may be called in parallel with the same
  76 *         transformation object. Data processing can happen synchronously
  77 *         [SHASH] or asynchronously [AHASH] at this point. Driver must not use
  78 *         req->result.
  79 * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the
  80 *         transformation and retrieves the resulting hash from the driver and
  81 *         pushes it back to upper layers. No data processing happens at this
  82 *         point unless hardware requires it to finish the transformation
  83 *         (then the data buffered by the device driver is processed).
  84 * @finup: **[optional]** Combination of @update and @final. This function is effectively a
  85 *         combination of @update and @final calls issued in sequence. As some
  86 *         hardware cannot do @update and @final separately, this callback was
  87 *         added to allow such hardware to be used at least by IPsec. Data
  88 *         processing can happen synchronously [SHASH] or asynchronously [AHASH]
  89 *         at this point.
  90 * @digest: Combination of @init and @update and @final. This function
  91 *          effectively behaves as the entire chain of operations, @init,
  92 *          @update and @final issued in sequence. Just like @finup, this was
  93 *          added for hardware which cannot do even the @finup, but can only do
  94 *          the whole transformation in one run. Data processing can happen
  95 *          synchronously [SHASH] or asynchronously [AHASH] at this point.
  96 * @setkey: Set optional key used by the hashing algorithm. Intended to push
  97 *          optional key used by the hashing algorithm from upper layers into
  98 *          the driver. This function can store the key in the transformation
  99 *          context or can outright program it into the hardware. In the former
 100 *          case, one must be careful to program the key into the hardware at
 101 *          appropriate time and one must be careful that .setkey() can be
 102 *          called multiple times during the existence of the transformation
 103 *          object. Not  all hashing algorithms do implement this function as it
 104 *          is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
 105 *          implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
 106 *          this function. This function must be called before any other of the
 107 *          @init, @update, @final, @finup, @digest is called. No data
 108 *          processing happens at this point.
 109 * @export: Export partial state of the transformation. This function dumps the
 110 *          entire state of the ongoing transformation into a provided block of
 111 *          data so it can be @import 'ed back later on. This is useful in case
 112 *          you want to save partial result of the transformation after
 113 *          processing certain amount of data and reload this partial result
 114 *          multiple times later on for multiple re-use. No data processing
 115 *          happens at this point. Driver must not use req->result.
 116 * @import: Import partial state of the transformation. This function loads the
 117 *          entire state of the ongoing transformation from a provided block of
 118 *          data so the transformation can continue from this point onward. No
 119 *          data processing happens at this point. Driver must not use
 120 *          req->result.
 121 * @init_tfm: Initialize the cryptographic transformation object.
 122 *            This function is called only once at the instantiation
 123 *            time, right after the transformation context was
 124 *            allocated. In case the cryptographic hardware has
 125 *            some special requirements which need to be handled
 126 *            by software, this function shall check for the precise
 127 *            requirement of the transformation and put any software
 128 *            fallbacks in place.
 129 * @exit_tfm: Deinitialize the cryptographic transformation object.
 130 *            This is a counterpart to @init_tfm, used to remove
 131 *            various changes set in @init_tfm.
 132 * @halg: see struct hash_alg_common
 133 */
 134struct ahash_alg {
 135        int (*init)(struct ahash_request *req);
 136        int (*update)(struct ahash_request *req);
 137        int (*final)(struct ahash_request *req);
 138        int (*finup)(struct ahash_request *req);
 139        int (*digest)(struct ahash_request *req);
 140        int (*export)(struct ahash_request *req, void *out);
 141        int (*import)(struct ahash_request *req, const void *in);
 142        int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
 143                      unsigned int keylen);
 144        int (*init_tfm)(struct crypto_ahash *tfm);
 145        void (*exit_tfm)(struct crypto_ahash *tfm);
 146
 147        struct hash_alg_common halg;
 148};
 149
 150struct shash_desc {
 151        struct crypto_shash *tfm;
 152        void *__ctx[] __aligned(ARCH_SLAB_MINALIGN);
 153};
 154
 155#define HASH_MAX_DIGESTSIZE      64
 156
 157/*
 158 * Worst case is hmac(sha3-224-generic).  Its context is a nested 'shash_desc'
 159 * containing a 'struct sha3_state'.
 160 */
 161#define HASH_MAX_DESCSIZE       (sizeof(struct shash_desc) + 360)
 162
 163#define HASH_MAX_STATESIZE      512
 164
 165#define SHASH_DESC_ON_STACK(shash, ctx)                                      \
 166        char __##shash##_desc[sizeof(struct shash_desc) + HASH_MAX_DESCSIZE] \
 167                __aligned(__alignof__(struct shash_desc));                   \
 168        struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
 169
 170/**
 171 * struct shash_alg - synchronous message digest definition
 172 * @init: see struct ahash_alg
 173 * @update: see struct ahash_alg
 174 * @final: see struct ahash_alg
 175 * @finup: see struct ahash_alg
 176 * @digest: see struct ahash_alg
 177 * @export: see struct ahash_alg
 178 * @import: see struct ahash_alg
 179 * @setkey: see struct ahash_alg
 180 * @init_tfm: Initialize the cryptographic transformation object.
 181 *            This function is called only once at the instantiation
 182 *            time, right after the transformation context was
 183 *            allocated. In case the cryptographic hardware has
 184 *            some special requirements which need to be handled
 185 *            by software, this function shall check for the precise
 186 *            requirement of the transformation and put any software
 187 *            fallbacks in place.
 188 * @exit_tfm: Deinitialize the cryptographic transformation object.
 189 *            This is a counterpart to @init_tfm, used to remove
 190 *            various changes set in @init_tfm.
 191 * @digestsize: see struct ahash_alg
 192 * @statesize: see struct ahash_alg
 193 * @descsize: Size of the operational state for the message digest. This state
 194 *            size is the memory size that needs to be allocated for
 195 *            shash_desc.__ctx
 196 * @base: internally used
 197 */
 198struct shash_alg {
 199        int (*init)(struct shash_desc *desc);
 200        int (*update)(struct shash_desc *desc, const u8 *data,
 201                      unsigned int len);
 202        int (*final)(struct shash_desc *desc, u8 *out);
 203        int (*finup)(struct shash_desc *desc, const u8 *data,
 204                     unsigned int len, u8 *out);
 205        int (*digest)(struct shash_desc *desc, const u8 *data,
 206                      unsigned int len, u8 *out);
 207        int (*export)(struct shash_desc *desc, void *out);
 208        int (*import)(struct shash_desc *desc, const void *in);
 209        int (*setkey)(struct crypto_shash *tfm, const u8 *key,
 210                      unsigned int keylen);
 211        int (*init_tfm)(struct crypto_shash *tfm);
 212        void (*exit_tfm)(struct crypto_shash *tfm);
 213
 214        unsigned int descsize;
 215
 216        /* These fields must match hash_alg_common. */
 217        unsigned int digestsize
 218                __attribute__ ((aligned(__alignof__(struct hash_alg_common))));
 219        unsigned int statesize;
 220
 221        struct crypto_alg base;
 222};
 223
 224struct crypto_ahash {
 225        int (*init)(struct ahash_request *req);
 226        int (*update)(struct ahash_request *req);
 227        int (*final)(struct ahash_request *req);
 228        int (*finup)(struct ahash_request *req);
 229        int (*digest)(struct ahash_request *req);
 230        int (*export)(struct ahash_request *req, void *out);
 231        int (*import)(struct ahash_request *req, const void *in);
 232        int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
 233                      unsigned int keylen);
 234
 235        unsigned int reqsize;
 236        struct crypto_tfm base;
 237};
 238
 239struct crypto_shash {
 240        unsigned int descsize;
 241        struct crypto_tfm base;
 242};
 243
 244/**
 245 * DOC: Asynchronous Message Digest API
 246 *
 247 * The asynchronous message digest API is used with the ciphers of type
 248 * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto)
 249 *
 250 * The asynchronous cipher operation discussion provided for the
 251 * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well.
 252 */
 253
 254static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
 255{
 256        return container_of(tfm, struct crypto_ahash, base);
 257}
 258
 259/**
 260 * crypto_alloc_ahash() - allocate ahash cipher handle
 261 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
 262 *            ahash cipher
 263 * @type: specifies the type of the cipher
 264 * @mask: specifies the mask for the cipher
 265 *
 266 * Allocate a cipher handle for an ahash. The returned struct
 267 * crypto_ahash is the cipher handle that is required for any subsequent
 268 * API invocation for that ahash.
 269 *
 270 * Return: allocated cipher handle in case of success; IS_ERR() is true in case
 271 *         of an error, PTR_ERR() returns the error code.
 272 */
 273struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type,
 274                                        u32 mask);
 275
 276static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
 277{
 278        return &tfm->base;
 279}
 280
 281/**
 282 * crypto_free_ahash() - zeroize and free the ahash handle
 283 * @tfm: cipher handle to be freed
 284 *
 285 * If @tfm is a NULL or error pointer, this function does nothing.
 286 */
 287static inline void crypto_free_ahash(struct crypto_ahash *tfm)
 288{
 289        crypto_destroy_tfm(tfm, crypto_ahash_tfm(tfm));
 290}
 291
 292/**
 293 * crypto_has_ahash() - Search for the availability of an ahash.
 294 * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
 295 *            ahash
 296 * @type: specifies the type of the ahash
 297 * @mask: specifies the mask for the ahash
 298 *
 299 * Return: true when the ahash is known to the kernel crypto API; false
 300 *         otherwise
 301 */
 302int crypto_has_ahash(const char *alg_name, u32 type, u32 mask);
 303
 304static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm)
 305{
 306        return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
 307}
 308
 309static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
 310{
 311        return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
 312}
 313
 314static inline unsigned int crypto_ahash_alignmask(
 315        struct crypto_ahash *tfm)
 316{
 317        return crypto_tfm_alg_alignmask(crypto_ahash_tfm(tfm));
 318}
 319
 320/**
 321 * crypto_ahash_blocksize() - obtain block size for cipher
 322 * @tfm: cipher handle
 323 *
 324 * The block size for the message digest cipher referenced with the cipher
 325 * handle is returned.
 326 *
 327 * Return: block size of cipher
 328 */
 329static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm)
 330{
 331        return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
 332}
 333
 334static inline struct hash_alg_common *__crypto_hash_alg_common(
 335        struct crypto_alg *alg)
 336{
 337        return container_of(alg, struct hash_alg_common, base);
 338}
 339
 340static inline struct hash_alg_common *crypto_hash_alg_common(
 341        struct crypto_ahash *tfm)
 342{
 343        return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
 344}
 345
 346/**
 347 * crypto_ahash_digestsize() - obtain message digest size
 348 * @tfm: cipher handle
 349 *
 350 * The size for the message digest created by the message digest cipher
 351 * referenced with the cipher handle is returned.
 352 *
 353 *
 354 * Return: message digest size of cipher
 355 */
 356static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm)
 357{
 358        return crypto_hash_alg_common(tfm)->digestsize;
 359}
 360
 361/**
 362 * crypto_ahash_statesize() - obtain size of the ahash state
 363 * @tfm: cipher handle
 364 *
 365 * Return the size of the ahash state. With the crypto_ahash_export()
 366 * function, the caller can export the state into a buffer whose size is
 367 * defined with this function.
 368 *
 369 * Return: size of the ahash state
 370 */
 371static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm)
 372{
 373        return crypto_hash_alg_common(tfm)->statesize;
 374}
 375
 376static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
 377{
 378        return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
 379}
 380
 381static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
 382{
 383        crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
 384}
 385
 386static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
 387{
 388        crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), flags);
 389}
 390
 391/**
 392 * crypto_ahash_reqtfm() - obtain cipher handle from request
 393 * @req: asynchronous request handle that contains the reference to the ahash
 394 *       cipher handle
 395 *
 396 * Return the ahash cipher handle that is registered with the asynchronous
 397 * request handle ahash_request.
 398 *
 399 * Return: ahash cipher handle
 400 */
 401static inline struct crypto_ahash *crypto_ahash_reqtfm(
 402        struct ahash_request *req)
 403{
 404        return __crypto_ahash_cast(req->base.tfm);
 405}
 406
 407/**
 408 * crypto_ahash_reqsize() - obtain size of the request data structure
 409 * @tfm: cipher handle
 410 *
 411 * Return: size of the request data
 412 */
 413static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm)
 414{
 415        return tfm->reqsize;
 416}
 417
 418static inline void *ahash_request_ctx(struct ahash_request *req)
 419{
 420        return req->__ctx;
 421}
 422
 423/**
 424 * crypto_ahash_setkey - set key for cipher handle
 425 * @tfm: cipher handle
 426 * @key: buffer holding the key
 427 * @keylen: length of the key in bytes
 428 *
 429 * The caller provided key is set for the ahash cipher. The cipher
 430 * handle must point to a keyed hash in order for this function to succeed.
 431 *
 432 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
 433 */
 434int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
 435                        unsigned int keylen);
 436
 437/**
 438 * crypto_ahash_finup() - update and finalize message digest
 439 * @req: reference to the ahash_request handle that holds all information
 440 *       needed to perform the cipher operation
 441 *
 442 * This function is a "short-hand" for the function calls of
 443 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
 444 * meaning as discussed for those separate functions.
 445 *
 446 * Return: see crypto_ahash_final()
 447 */
 448int crypto_ahash_finup(struct ahash_request *req);
 449
 450/**
 451 * crypto_ahash_final() - calculate message digest
 452 * @req: reference to the ahash_request handle that holds all information
 453 *       needed to perform the cipher operation
 454 *
 455 * Finalize the message digest operation and create the message digest
 456 * based on all data added to the cipher handle. The message digest is placed
 457 * into the output buffer registered with the ahash_request handle.
 458 *
 459 * Return:
 460 * 0            if the message digest was successfully calculated;
 461 * -EINPROGRESS if data is feeded into hardware (DMA) or queued for later;
 462 * -EBUSY       if queue is full and request should be resubmitted later;
 463 * other < 0    if an error occurred
 464 */
 465int crypto_ahash_final(struct ahash_request *req);
 466
 467/**
 468 * crypto_ahash_digest() - calculate message digest for a buffer
 469 * @req: reference to the ahash_request handle that holds all information
 470 *       needed to perform the cipher operation
 471 *
 472 * This function is a "short-hand" for the function calls of crypto_ahash_init,
 473 * crypto_ahash_update and crypto_ahash_final. The parameters have the same
 474 * meaning as discussed for those separate three functions.
 475 *
 476 * Return: see crypto_ahash_final()
 477 */
 478int crypto_ahash_digest(struct ahash_request *req);
 479
 480/**
 481 * crypto_ahash_export() - extract current message digest state
 482 * @req: reference to the ahash_request handle whose state is exported
 483 * @out: output buffer of sufficient size that can hold the hash state
 484 *
 485 * This function exports the hash state of the ahash_request handle into the
 486 * caller-allocated output buffer out which must have sufficient size (e.g. by
 487 * calling crypto_ahash_statesize()).
 488 *
 489 * Return: 0 if the export was successful; < 0 if an error occurred
 490 */
 491static inline int crypto_ahash_export(struct ahash_request *req, void *out)
 492{
 493        return crypto_ahash_reqtfm(req)->export(req, out);
 494}
 495
 496/**
 497 * crypto_ahash_import() - import message digest state
 498 * @req: reference to ahash_request handle the state is imported into
 499 * @in: buffer holding the state
 500 *
 501 * This function imports the hash state into the ahash_request handle from the
 502 * input buffer. That buffer should have been generated with the
 503 * crypto_ahash_export function.
 504 *
 505 * Return: 0 if the import was successful; < 0 if an error occurred
 506 */
 507static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
 508{
 509        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 510
 511        if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 512                return -ENOKEY;
 513
 514        return tfm->import(req, in);
 515}
 516
 517/**
 518 * crypto_ahash_init() - (re)initialize message digest handle
 519 * @req: ahash_request handle that already is initialized with all necessary
 520 *       data using the ahash_request_* API functions
 521 *
 522 * The call (re-)initializes the message digest referenced by the ahash_request
 523 * handle. Any potentially existing state created by previous operations is
 524 * discarded.
 525 *
 526 * Return: see crypto_ahash_final()
 527 */
 528static inline int crypto_ahash_init(struct ahash_request *req)
 529{
 530        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 531
 532        if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 533                return -ENOKEY;
 534
 535        return tfm->init(req);
 536}
 537
 538/**
 539 * crypto_ahash_update() - add data to message digest for processing
 540 * @req: ahash_request handle that was previously initialized with the
 541 *       crypto_ahash_init call.
 542 *
 543 * Updates the message digest state of the &ahash_request handle. The input data
 544 * is pointed to by the scatter/gather list registered in the &ahash_request
 545 * handle
 546 *
 547 * Return: see crypto_ahash_final()
 548 */
 549static inline int crypto_ahash_update(struct ahash_request *req)
 550{
 551        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 552        struct crypto_alg *alg = tfm->base.__crt_alg;
 553        unsigned int nbytes = req->nbytes;
 554        int ret;
 555
 556        crypto_stats_get(alg);
 557        ret = crypto_ahash_reqtfm(req)->update(req);
 558        crypto_stats_ahash_update(nbytes, ret, alg);
 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 */
 581static 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 */
 599static 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 */
 617static inline void ahash_request_free(struct ahash_request *req)
 618{
 619        kfree_sensitive(req);
 620}
 621
 622static 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
 628static 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 */
 659static 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 */
 682static 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 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 */
 718struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
 719                                        u32 mask);
 720
 721static 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 * If @tfm is a NULL or error pointer, this function does nothing.
 731 */
 732static inline void crypto_free_shash(struct crypto_shash *tfm)
 733{
 734        crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
 735}
 736
 737static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
 738{
 739        return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
 740}
 741
 742static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
 743{
 744        return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
 745}
 746
 747static inline unsigned int crypto_shash_alignmask(
 748        struct crypto_shash *tfm)
 749{
 750        return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
 751}
 752
 753/**
 754 * crypto_shash_blocksize() - obtain block size for cipher
 755 * @tfm: cipher handle
 756 *
 757 * The block size for the message digest cipher referenced with the cipher
 758 * handle is returned.
 759 *
 760 * Return: block size of cipher
 761 */
 762static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm)
 763{
 764        return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
 765}
 766
 767static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
 768{
 769        return container_of(alg, struct shash_alg, base);
 770}
 771
 772static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
 773{
 774        return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
 775}
 776
 777/**
 778 * crypto_shash_digestsize() - obtain message digest size
 779 * @tfm: cipher handle
 780 *
 781 * The size for the message digest created by the message digest cipher
 782 * referenced with the cipher handle is returned.
 783 *
 784 * Return: digest size of cipher
 785 */
 786static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
 787{
 788        return crypto_shash_alg(tfm)->digestsize;
 789}
 790
 791static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
 792{
 793        return crypto_shash_alg(tfm)->statesize;
 794}
 795
 796static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
 797{
 798        return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
 799}
 800
 801static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
 802{
 803        crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
 804}
 805
 806static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
 807{
 808        crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
 809}
 810
 811/**
 812 * crypto_shash_descsize() - obtain the operational state size
 813 * @tfm: cipher handle
 814 *
 815 * The size of the operational state the cipher needs during operation is
 816 * returned for the hash referenced with the cipher handle. This size is
 817 * required to calculate the memory requirements to allow the caller allocating
 818 * sufficient memory for operational state.
 819 *
 820 * The operational state is defined with struct shash_desc where the size of
 821 * that data structure is to be calculated as
 822 * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
 823 *
 824 * Return: size of the operational state
 825 */
 826static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
 827{
 828        return tfm->descsize;
 829}
 830
 831static inline void *shash_desc_ctx(struct shash_desc *desc)
 832{
 833        return desc->__ctx;
 834}
 835
 836/**
 837 * crypto_shash_setkey() - set key for message digest
 838 * @tfm: cipher handle
 839 * @key: buffer holding the key
 840 * @keylen: length of the key in bytes
 841 *
 842 * The caller provided key is set for the keyed message digest cipher. The
 843 * cipher handle must point to a keyed message digest cipher in order for this
 844 * function to succeed.
 845 *
 846 * Context: Any context.
 847 * Return: 0 if the setting of the key was successful; < 0 if an error occurred
 848 */
 849int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
 850                        unsigned int keylen);
 851
 852/**
 853 * crypto_shash_digest() - calculate message digest for buffer
 854 * @desc: see crypto_shash_final()
 855 * @data: see crypto_shash_update()
 856 * @len: see crypto_shash_update()
 857 * @out: see crypto_shash_final()
 858 *
 859 * This function is a "short-hand" for the function calls of crypto_shash_init,
 860 * crypto_shash_update and crypto_shash_final. The parameters have the same
 861 * meaning as discussed for those separate three functions.
 862 *
 863 * Context: Any context.
 864 * Return: 0 if the message digest creation was successful; < 0 if an error
 865 *         occurred
 866 */
 867int crypto_shash_digest(struct shash_desc *desc, const u8 *data,
 868                        unsigned int len, u8 *out);
 869
 870/**
 871 * crypto_shash_tfm_digest() - calculate message digest for buffer
 872 * @tfm: hash transformation object
 873 * @data: see crypto_shash_update()
 874 * @len: see crypto_shash_update()
 875 * @out: see crypto_shash_final()
 876 *
 877 * This is a simplified version of crypto_shash_digest() for users who don't
 878 * want to allocate their own hash descriptor (shash_desc).  Instead,
 879 * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash)
 880 * directly, and it allocates a hash descriptor on the stack internally.
 881 * Note that this stack allocation may be fairly large.
 882 *
 883 * Context: Any context.
 884 * Return: 0 on success; < 0 if an error occurred.
 885 */
 886int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data,
 887                            unsigned int len, u8 *out);
 888
 889/**
 890 * crypto_shash_export() - extract operational state for message digest
 891 * @desc: reference to the operational state handle whose state is exported
 892 * @out: output buffer of sufficient size that can hold the hash state
 893 *
 894 * This function exports the hash state of the operational state handle into the
 895 * caller-allocated output buffer out which must have sufficient size (e.g. by
 896 * calling crypto_shash_descsize).
 897 *
 898 * Context: Any context.
 899 * Return: 0 if the export creation was successful; < 0 if an error occurred
 900 */
 901static inline int crypto_shash_export(struct shash_desc *desc, void *out)
 902{
 903        return crypto_shash_alg(desc->tfm)->export(desc, out);
 904}
 905
 906/**
 907 * crypto_shash_import() - import operational state
 908 * @desc: reference to the operational state handle the state imported into
 909 * @in: buffer holding the state
 910 *
 911 * This function imports the hash state into the operational state handle from
 912 * the input buffer. That buffer should have been generated with the
 913 * crypto_ahash_export function.
 914 *
 915 * Context: Any context.
 916 * Return: 0 if the import was successful; < 0 if an error occurred
 917 */
 918static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
 919{
 920        struct crypto_shash *tfm = desc->tfm;
 921
 922        if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 923                return -ENOKEY;
 924
 925        return crypto_shash_alg(tfm)->import(desc, in);
 926}
 927
 928/**
 929 * crypto_shash_init() - (re)initialize message digest
 930 * @desc: operational state handle that is already filled
 931 *
 932 * The call (re-)initializes the message digest referenced by the
 933 * operational state handle. Any potentially existing state created by
 934 * previous operations is discarded.
 935 *
 936 * Context: Any context.
 937 * Return: 0 if the message digest initialization was successful; < 0 if an
 938 *         error occurred
 939 */
 940static inline int crypto_shash_init(struct shash_desc *desc)
 941{
 942        struct crypto_shash *tfm = desc->tfm;
 943
 944        if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
 945                return -ENOKEY;
 946
 947        return crypto_shash_alg(tfm)->init(desc);
 948}
 949
 950/**
 951 * crypto_shash_update() - add data to message digest for processing
 952 * @desc: operational state handle that is already initialized
 953 * @data: input data to be added to the message digest
 954 * @len: length of the input data
 955 *
 956 * Updates the message digest state of the operational state handle.
 957 *
 958 * Context: Any context.
 959 * Return: 0 if the message digest update was successful; < 0 if an error
 960 *         occurred
 961 */
 962int crypto_shash_update(struct shash_desc *desc, const u8 *data,
 963                        unsigned int len);
 964
 965/**
 966 * crypto_shash_final() - calculate message digest
 967 * @desc: operational state handle that is already filled with data
 968 * @out: output buffer filled with the message digest
 969 *
 970 * Finalize the message digest operation and create the message digest
 971 * based on all data added to the cipher handle. The message digest is placed
 972 * into the output buffer. The caller must ensure that the output buffer is
 973 * large enough by using crypto_shash_digestsize.
 974 *
 975 * Context: Any context.
 976 * Return: 0 if the message digest creation was successful; < 0 if an error
 977 *         occurred
 978 */
 979int crypto_shash_final(struct shash_desc *desc, u8 *out);
 980
 981/**
 982 * crypto_shash_finup() - calculate message digest of buffer
 983 * @desc: see crypto_shash_final()
 984 * @data: see crypto_shash_update()
 985 * @len: see crypto_shash_update()
 986 * @out: see crypto_shash_final()
 987 *
 988 * This function is a "short-hand" for the function calls of
 989 * crypto_shash_update and crypto_shash_final. The parameters have the same
 990 * meaning as discussed for those separate functions.
 991 *
 992 * Context: Any context.
 993 * Return: 0 if the message digest creation was successful; < 0 if an error
 994 *         occurred
 995 */
 996int crypto_shash_finup(struct shash_desc *desc, const u8 *data,
 997                       unsigned int len, u8 *out);
 998
 999static inline void shash_desc_zero(struct shash_desc *desc)
1000{
1001        memzero_explicit(desc,
1002                         sizeof(*desc) + crypto_shash_descsize(desc->tfm));
1003}
1004
1005#endif  /* _CRYPTO_HASH_H */
1006