/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * Hash: Hash algorithms under the crypto API * * Copyright (c) 2008 Herbert Xu <[email protected]> */ #ifndef _CRYPTO_HASH_H #define _CRYPTO_HASH_H #include <linux/atomic.h> #include <linux/crypto.h> #include <linux/string.h> struct crypto_ahash; /** * DOC: Message Digest Algorithm Definitions * * These data structures define modular message digest algorithm * implementations, managed via crypto_register_ahash(), * crypto_register_shash(), crypto_unregister_ahash() and * crypto_unregister_shash(). */ /* * struct hash_alg_common - define properties of message digest * @digestsize: Size of the result of the transformation. A buffer of this size * must be available to the @final and @finup calls, so they can * store the resulting hash into it. For various predefined sizes, * search include/crypto/ using * git grep _DIGEST_SIZE include/crypto. * @statesize: Size of the block for partial state of the transformation. A * buffer of this size must be passed to the @export function as it * will save the partial state of the transformation into it. On the * other side, the @import function will load the state from a * buffer of this size as well. * @base: Start of data structure of cipher algorithm. The common data * structure of crypto_alg contains information common to all ciphers. * The hash_alg_common data structure now adds the hash-specific * information. */ #define HASH_ALG_COMMON … struct hash_alg_common HASH_ALG_COMMON; struct ahash_request { … }; /** * struct ahash_alg - asynchronous message digest definition * @init: **[mandatory]** Initialize the transformation context. Intended only to initialize the * state of the HASH transformation at the beginning. This shall fill in * the internal structures used during the entire duration of the whole * transformation. No data processing happens at this point. Driver code * implementation must not use req->result. * @update: **[mandatory]** Push a chunk of data into the driver for transformation. This * function actually pushes blocks of data from upper layers into the * driver, which then passes those to the hardware as seen fit. This * function must not finalize the HASH transformation by calculating the * final message digest as this only adds more data into the * transformation. This function shall not modify the transformation * context, as this function may be called in parallel with the same * transformation object. Data processing can happen synchronously * [SHASH] or asynchronously [AHASH] at this point. Driver must not use * req->result. * @final: **[mandatory]** Retrieve result from the driver. This function finalizes the * transformation and retrieves the resulting hash from the driver and * pushes it back to upper layers. No data processing happens at this * point unless hardware requires it to finish the transformation * (then the data buffered by the device driver is processed). * @finup: **[optional]** Combination of @update and @final. This function is effectively a * combination of @update and @final calls issued in sequence. As some * hardware cannot do @update and @final separately, this callback was * added to allow such hardware to be used at least by IPsec. Data * processing can happen synchronously [SHASH] or asynchronously [AHASH] * at this point. * @digest: Combination of @init and @update and @final. This function * effectively behaves as the entire chain of operations, @init, * @update and @final issued in sequence. Just like @finup, this was * added for hardware which cannot do even the @finup, but can only do * the whole transformation in one run. Data processing can happen * synchronously [SHASH] or asynchronously [AHASH] at this point. * @setkey: Set optional key used by the hashing algorithm. Intended to push * optional key used by the hashing algorithm from upper layers into * the driver. This function can store the key in the transformation * context or can outright program it into the hardware. In the former * case, one must be careful to program the key into the hardware at * appropriate time and one must be careful that .setkey() can be * called multiple times during the existence of the transformation * object. Not all hashing algorithms do implement this function as it * is only needed for keyed message digests. SHAx/MDx/CRCx do NOT * implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement * this function. This function must be called before any other of the * @init, @update, @final, @finup, @digest is called. No data * processing happens at this point. * @export: Export partial state of the transformation. This function dumps the * entire state of the ongoing transformation into a provided block of * data so it can be @import 'ed back later on. This is useful in case * you want to save partial result of the transformation after * processing certain amount of data and reload this partial result * multiple times later on for multiple re-use. No data processing * happens at this point. Driver must not use req->result. * @import: Import partial state of the transformation. This function loads the * entire state of the ongoing transformation from a provided block of * data so the transformation can continue from this point onward. No * data processing happens at this point. Driver must not use * req->result. * @init_tfm: Initialize the cryptographic transformation object. * This function is called only once at the instantiation * time, right after the transformation context was * allocated. In case the cryptographic hardware has * some special requirements which need to be handled * by software, this function shall check for the precise * requirement of the transformation and put any software * fallbacks in place. * @exit_tfm: Deinitialize the cryptographic transformation object. * This is a counterpart to @init_tfm, used to remove * various changes set in @init_tfm. * @clone_tfm: Copy transform into new object, may allocate memory. * @halg: see struct hash_alg_common */ struct ahash_alg { … }; struct shash_desc { … }; #define HASH_MAX_DIGESTSIZE … /* * Worst case is hmac(sha3-224-generic). Its context is a nested 'shash_desc' * containing a 'struct sha3_state'. */ #define HASH_MAX_DESCSIZE … #define SHASH_DESC_ON_STACK(shash, ctx) … /** * struct shash_alg - synchronous message digest definition * @init: see struct ahash_alg * @update: see struct ahash_alg * @final: see struct ahash_alg * @finup: see struct ahash_alg * @digest: see struct ahash_alg * @export: see struct ahash_alg * @import: see struct ahash_alg * @setkey: see struct ahash_alg * @init_tfm: Initialize the cryptographic transformation object. * This function is called only once at the instantiation * time, right after the transformation context was * allocated. In case the cryptographic hardware has * some special requirements which need to be handled * by software, this function shall check for the precise * requirement of the transformation and put any software * fallbacks in place. * @exit_tfm: Deinitialize the cryptographic transformation object. * This is a counterpart to @init_tfm, used to remove * various changes set in @init_tfm. * @clone_tfm: Copy transform into new object, may allocate memory. * @descsize: Size of the operational state for the message digest. This state * size is the memory size that needs to be allocated for * shash_desc.__ctx * @halg: see struct hash_alg_common * @HASH_ALG_COMMON: see struct hash_alg_common */ struct shash_alg { … }; #undef HASH_ALG_COMMON struct crypto_ahash { … }; struct crypto_shash { … }; /** * DOC: Asynchronous Message Digest API * * The asynchronous message digest API is used with the ciphers of type * CRYPTO_ALG_TYPE_AHASH (listed as type "ahash" in /proc/crypto) * * The asynchronous cipher operation discussion provided for the * CRYPTO_ALG_TYPE_SKCIPHER API applies here as well. */ static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm) { … } /** * crypto_alloc_ahash() - allocate ahash cipher handle * @alg_name: is the cra_name / name or cra_driver_name / driver name of the * ahash cipher * @type: specifies the type of the cipher * @mask: specifies the mask for the cipher * * Allocate a cipher handle for an ahash. The returned struct * crypto_ahash is the cipher handle that is required for any subsequent * API invocation for that ahash. * * Return: allocated cipher handle in case of success; IS_ERR() is true in case * of an error, PTR_ERR() returns the error code. */ struct crypto_ahash *crypto_alloc_ahash(const char *alg_name, u32 type, u32 mask); struct crypto_ahash *crypto_clone_ahash(struct crypto_ahash *tfm); static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm) { … } /** * crypto_free_ahash() - zeroize and free the ahash handle * @tfm: cipher handle to be freed * * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_ahash(struct crypto_ahash *tfm) { … } /** * crypto_has_ahash() - Search for the availability of an ahash. * @alg_name: is the cra_name / name or cra_driver_name / driver name of the * ahash * @type: specifies the type of the ahash * @mask: specifies the mask for the ahash * * Return: true when the ahash is known to the kernel crypto API; false * otherwise */ int crypto_has_ahash(const char *alg_name, u32 type, u32 mask); static inline const char *crypto_ahash_alg_name(struct crypto_ahash *tfm) { … } static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm) { … } /** * crypto_ahash_blocksize() - obtain block size for cipher * @tfm: cipher handle * * The block size for the message digest cipher referenced with the cipher * handle is returned. * * Return: block size of cipher */ static inline unsigned int crypto_ahash_blocksize(struct crypto_ahash *tfm) { … } static inline struct hash_alg_common *__crypto_hash_alg_common( struct crypto_alg *alg) { … } static inline struct hash_alg_common *crypto_hash_alg_common( struct crypto_ahash *tfm) { … } /** * crypto_ahash_digestsize() - obtain message digest size * @tfm: cipher handle * * The size for the message digest created by the message digest cipher * referenced with the cipher handle is returned. * * * Return: message digest size of cipher */ static inline unsigned int crypto_ahash_digestsize(struct crypto_ahash *tfm) { … } /** * crypto_ahash_statesize() - obtain size of the ahash state * @tfm: cipher handle * * Return the size of the ahash state. With the crypto_ahash_export() * function, the caller can export the state into a buffer whose size is * defined with this function. * * Return: size of the ahash state */ static inline unsigned int crypto_ahash_statesize(struct crypto_ahash *tfm) { … } static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm) { … } static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags) { … } static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags) { … } /** * crypto_ahash_reqtfm() - obtain cipher handle from request * @req: asynchronous request handle that contains the reference to the ahash * cipher handle * * Return the ahash cipher handle that is registered with the asynchronous * request handle ahash_request. * * Return: ahash cipher handle */ static inline struct crypto_ahash *crypto_ahash_reqtfm( struct ahash_request *req) { … } /** * crypto_ahash_reqsize() - obtain size of the request data structure * @tfm: cipher handle * * Return: size of the request data */ static inline unsigned int crypto_ahash_reqsize(struct crypto_ahash *tfm) { … } static inline void *ahash_request_ctx(struct ahash_request *req) { … } /** * crypto_ahash_setkey - set key for cipher handle * @tfm: cipher handle * @key: buffer holding the key * @keylen: length of the key in bytes * * The caller provided key is set for the ahash cipher. The cipher * handle must point to a keyed hash in order for this function to succeed. * * Return: 0 if the setting of the key was successful; < 0 if an error occurred */ int crypto_ahash_setkey(struct crypto_ahash *tfm, const u8 *key, unsigned int keylen); /** * crypto_ahash_finup() - update and finalize message digest * @req: reference to the ahash_request handle that holds all information * needed to perform the cipher operation * * This function is a "short-hand" for the function calls of * crypto_ahash_update and crypto_ahash_final. The parameters have the same * meaning as discussed for those separate functions. * * Return: see crypto_ahash_final() */ int crypto_ahash_finup(struct ahash_request *req); /** * crypto_ahash_final() - calculate message digest * @req: reference to the ahash_request handle that holds all information * needed to perform the cipher operation * * Finalize the message digest operation and create the message digest * based on all data added to the cipher handle. The message digest is placed * into the output buffer registered with the ahash_request handle. * * Return: * 0 if the message digest was successfully calculated; * -EINPROGRESS if data is fed into hardware (DMA) or queued for later; * -EBUSY if queue is full and request should be resubmitted later; * other < 0 if an error occurred */ int crypto_ahash_final(struct ahash_request *req); /** * crypto_ahash_digest() - calculate message digest for a buffer * @req: reference to the ahash_request handle that holds all information * needed to perform the cipher operation * * This function is a "short-hand" for the function calls of crypto_ahash_init, * crypto_ahash_update and crypto_ahash_final. The parameters have the same * meaning as discussed for those separate three functions. * * Return: see crypto_ahash_final() */ int crypto_ahash_digest(struct ahash_request *req); /** * crypto_ahash_export() - extract current message digest state * @req: reference to the ahash_request handle whose state is exported * @out: output buffer of sufficient size that can hold the hash state * * This function exports the hash state of the ahash_request handle into the * caller-allocated output buffer out which must have sufficient size (e.g. by * calling crypto_ahash_statesize()). * * Return: 0 if the export was successful; < 0 if an error occurred */ int crypto_ahash_export(struct ahash_request *req, void *out); /** * crypto_ahash_import() - import message digest state * @req: reference to ahash_request handle the state is imported into * @in: buffer holding the state * * This function imports the hash state into the ahash_request handle from the * input buffer. That buffer should have been generated with the * crypto_ahash_export function. * * Return: 0 if the import was successful; < 0 if an error occurred */ int crypto_ahash_import(struct ahash_request *req, const void *in); /** * crypto_ahash_init() - (re)initialize message digest handle * @req: ahash_request handle that already is initialized with all necessary * data using the ahash_request_* API functions * * The call (re-)initializes the message digest referenced by the ahash_request * handle. Any potentially existing state created by previous operations is * discarded. * * Return: see crypto_ahash_final() */ int crypto_ahash_init(struct ahash_request *req); /** * crypto_ahash_update() - add data to message digest for processing * @req: ahash_request handle that was previously initialized with the * crypto_ahash_init call. * * Updates the message digest state of the &ahash_request handle. The input data * is pointed to by the scatter/gather list registered in the &ahash_request * handle * * Return: see crypto_ahash_final() */ int crypto_ahash_update(struct ahash_request *req); /** * DOC: Asynchronous Hash Request Handle * * The &ahash_request data structure contains all pointers to data * required for the asynchronous cipher operation. This includes the cipher * handle (which can be used by multiple &ahash_request instances), pointer * to plaintext and the message digest output buffer, asynchronous callback * function, etc. It acts as a handle to the ahash_request_* API calls in a * similar way as ahash handle to the crypto_ahash_* API calls. */ /** * ahash_request_set_tfm() - update cipher handle reference in request * @req: request handle to be modified * @tfm: cipher handle that shall be added to the request handle * * Allow the caller to replace the existing ahash handle in the request * data structure with a different one. */ static inline void ahash_request_set_tfm(struct ahash_request *req, struct crypto_ahash *tfm) { … } /** * ahash_request_alloc() - allocate request data structure * @tfm: cipher handle to be registered with the request * @gfp: memory allocation flag that is handed to kmalloc by the API call. * * Allocate the request data structure that must be used with the ahash * message digest API calls. During * the allocation, the provided ahash handle * is registered in the request data structure. * * Return: allocated request handle in case of success, or NULL if out of memory */ static inline struct ahash_request *ahash_request_alloc_noprof( struct crypto_ahash *tfm, gfp_t gfp) { … } #define ahash_request_alloc(...) … /** * ahash_request_free() - zeroize and free the request data structure * @req: request data structure cipher handle to be freed */ static inline void ahash_request_free(struct ahash_request *req) { … } static inline void ahash_request_zero(struct ahash_request *req) { … } static inline struct ahash_request *ahash_request_cast( struct crypto_async_request *req) { … } /** * ahash_request_set_callback() - set asynchronous callback function * @req: request handle * @flags: specify zero or an ORing of the flags * CRYPTO_TFM_REQ_MAY_BACKLOG the request queue may back log and * increase the wait queue beyond the initial maximum size; * CRYPTO_TFM_REQ_MAY_SLEEP the request processing may sleep * @compl: callback function pointer to be registered with the request handle * @data: The data pointer refers to memory that is not used by the kernel * crypto API, but provided to the callback function for it to use. Here, * the caller can provide a reference to memory the callback function can * operate on. As the callback function is invoked asynchronously to the * related functionality, it may need to access data structures of the * related functionality which can be referenced using this pointer. The * callback function can access the memory via the "data" field in the * &crypto_async_request data structure provided to the callback function. * * This function allows setting the callback function that is triggered once * the cipher operation completes. * * The callback function is registered with the &ahash_request handle and * must comply with the following template:: * * void callback_function(struct crypto_async_request *req, int error) */ static inline void ahash_request_set_callback(struct ahash_request *req, u32 flags, crypto_completion_t compl, void *data) { … } /** * ahash_request_set_crypt() - set data buffers * @req: ahash_request handle to be updated * @src: source scatter/gather list * @result: buffer that is filled with the message digest -- the caller must * ensure that the buffer has sufficient space by, for example, calling * crypto_ahash_digestsize() * @nbytes: number of bytes to process from the source scatter/gather list * * By using this call, the caller references the source scatter/gather list. * The source scatter/gather list points to the data the message digest is to * be calculated for. */ static inline void ahash_request_set_crypt(struct ahash_request *req, struct scatterlist *src, u8 *result, unsigned int nbytes) { … } /** * DOC: Synchronous Message Digest API * * The synchronous message digest API is used with the ciphers of type * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto) * * The message digest API is able to maintain state information for the * caller. * * The synchronous message digest API can store user-related context in its * shash_desc request data structure. */ /** * crypto_alloc_shash() - allocate message digest handle * @alg_name: is the cra_name / name or cra_driver_name / driver name of the * message digest cipher * @type: specifies the type of the cipher * @mask: specifies the mask for the cipher * * Allocate a cipher handle for a message digest. The returned &struct * crypto_shash is the cipher handle that is required for any subsequent * API invocation for that message digest. * * Return: allocated cipher handle in case of success; IS_ERR() is true in case * of an error, PTR_ERR() returns the error code. */ struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type, u32 mask); struct crypto_shash *crypto_clone_shash(struct crypto_shash *tfm); int crypto_has_shash(const char *alg_name, u32 type, u32 mask); static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) { … } /** * crypto_free_shash() - zeroize and free the message digest handle * @tfm: cipher handle to be freed * * If @tfm is a NULL or error pointer, this function does nothing. */ static inline void crypto_free_shash(struct crypto_shash *tfm) { … } static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm) { … } static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm) { … } /** * crypto_shash_blocksize() - obtain block size for cipher * @tfm: cipher handle * * The block size for the message digest cipher referenced with the cipher * handle is returned. * * Return: block size of cipher */ static inline unsigned int crypto_shash_blocksize(struct crypto_shash *tfm) { … } static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg) { … } static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm) { … } /** * crypto_shash_digestsize() - obtain message digest size * @tfm: cipher handle * * The size for the message digest created by the message digest cipher * referenced with the cipher handle is returned. * * Return: digest size of cipher */ static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm) { … } static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm) { … } static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm) { … } static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags) { … } static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags) { … } /** * crypto_shash_descsize() - obtain the operational state size * @tfm: cipher handle * * The size of the operational state the cipher needs during operation is * returned for the hash referenced with the cipher handle. This size is * required to calculate the memory requirements to allow the caller allocating * sufficient memory for operational state. * * The operational state is defined with struct shash_desc where the size of * that data structure is to be calculated as * sizeof(struct shash_desc) + crypto_shash_descsize(alg) * * Return: size of the operational state */ static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm) { … } static inline void *shash_desc_ctx(struct shash_desc *desc) { … } /** * crypto_shash_setkey() - set key for message digest * @tfm: cipher handle * @key: buffer holding the key * @keylen: length of the key in bytes * * The caller provided key is set for the keyed message digest cipher. The * cipher handle must point to a keyed message digest cipher in order for this * function to succeed. * * Context: Any context. * Return: 0 if the setting of the key was successful; < 0 if an error occurred */ int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key, unsigned int keylen); /** * crypto_shash_digest() - calculate message digest for buffer * @desc: see crypto_shash_final() * @data: see crypto_shash_update() * @len: see crypto_shash_update() * @out: see crypto_shash_final() * * This function is a "short-hand" for the function calls of crypto_shash_init, * crypto_shash_update and crypto_shash_final. The parameters have the same * meaning as discussed for those separate three functions. * * Context: Any context. * Return: 0 if the message digest creation was successful; < 0 if an error * occurred */ int crypto_shash_digest(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out); /** * crypto_shash_tfm_digest() - calculate message digest for buffer * @tfm: hash transformation object * @data: see crypto_shash_update() * @len: see crypto_shash_update() * @out: see crypto_shash_final() * * This is a simplified version of crypto_shash_digest() for users who don't * want to allocate their own hash descriptor (shash_desc). Instead, * crypto_shash_tfm_digest() takes a hash transformation object (crypto_shash) * directly, and it allocates a hash descriptor on the stack internally. * Note that this stack allocation may be fairly large. * * Context: Any context. * Return: 0 on success; < 0 if an error occurred. */ int crypto_shash_tfm_digest(struct crypto_shash *tfm, const u8 *data, unsigned int len, u8 *out); /** * crypto_shash_export() - extract operational state for message digest * @desc: reference to the operational state handle whose state is exported * @out: output buffer of sufficient size that can hold the hash state * * This function exports the hash state of the operational state handle into the * caller-allocated output buffer out which must have sufficient size (e.g. by * calling crypto_shash_descsize). * * Context: Any context. * Return: 0 if the export creation was successful; < 0 if an error occurred */ int crypto_shash_export(struct shash_desc *desc, void *out); /** * crypto_shash_import() - import operational state * @desc: reference to the operational state handle the state imported into * @in: buffer holding the state * * This function imports the hash state into the operational state handle from * the input buffer. That buffer should have been generated with the * crypto_ahash_export function. * * Context: Any context. * Return: 0 if the import was successful; < 0 if an error occurred */ int crypto_shash_import(struct shash_desc *desc, const void *in); /** * crypto_shash_init() - (re)initialize message digest * @desc: operational state handle that is already filled * * The call (re-)initializes the message digest referenced by the * operational state handle. Any potentially existing state created by * previous operations is discarded. * * Context: Any context. * Return: 0 if the message digest initialization was successful; < 0 if an * error occurred */ static inline int crypto_shash_init(struct shash_desc *desc) { … } /** * crypto_shash_update() - add data to message digest for processing * @desc: operational state handle that is already initialized * @data: input data to be added to the message digest * @len: length of the input data * * Updates the message digest state of the operational state handle. * * Context: Any context. * Return: 0 if the message digest update was successful; < 0 if an error * occurred */ int crypto_shash_update(struct shash_desc *desc, const u8 *data, unsigned int len); /** * crypto_shash_final() - calculate message digest * @desc: operational state handle that is already filled with data * @out: output buffer filled with the message digest * * Finalize the message digest operation and create the message digest * based on all data added to the cipher handle. The message digest is placed * into the output buffer. The caller must ensure that the output buffer is * large enough by using crypto_shash_digestsize. * * Context: Any context. * Return: 0 if the message digest creation was successful; < 0 if an error * occurred */ int crypto_shash_final(struct shash_desc *desc, u8 *out); /** * crypto_shash_finup() - calculate message digest of buffer * @desc: see crypto_shash_final() * @data: see crypto_shash_update() * @len: see crypto_shash_update() * @out: see crypto_shash_final() * * This function is a "short-hand" for the function calls of * crypto_shash_update and crypto_shash_final. The parameters have the same * meaning as discussed for those separate functions. * * Context: Any context. * Return: 0 if the message digest creation was successful; < 0 if an error * occurred */ int crypto_shash_finup(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out); static inline void shash_desc_zero(struct shash_desc *desc) { … } #endif /* _CRYPTO_HASH_H */