linux/include/crypto/hash.h

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/*
* Hash: Hash algorithms under the crypto API
*
* Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
*
*/
#ifndef _CRYPTO_HASH_H
#define _CRYPTO_HASH_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.
*/
struct hash_alg_common {
unsigned int digestsize;
unsigned int statesize;
struct crypto_alg base;
};
struct ahash_request {
struct crypto_async_request base;
unsigned int nbytes;
struct scatterlist *src;
u8 *result;
/* This field may only be used by the ahash API code. */
void *priv;
void *__ctx[] CRYPTO_MINALIGN_ATTR;
};
#define AHASH_REQUEST_ON_STACK(name, ahash) \
char __##name##_desc[sizeof(struct ahash_request) + \
crypto_ahash_reqsize(ahash)] CRYPTO_MINALIGN_ATTR; \
struct ahash_request *name = (void *)__##name##_desc
/**
* struct ahash_alg - asynchronous message digest definition
* @init: 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.
* @update: 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.
* @final: 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.
* @finup: 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.
* @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.
* @halg: see struct hash_alg_common
*/
struct ahash_alg {
int (*init)(struct ahash_request *req);
int (*update)(struct ahash_request *req);
int (*final)(struct ahash_request *req);
int (*finup)(struct ahash_request *req);
int (*digest)(struct ahash_request *req);
int (*export)(struct ahash_request *req, void *out);
int (*import)(struct ahash_request *req, const void *in);
int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen);
struct hash_alg_common halg;
};
struct shash_desc {
struct crypto_shash *tfm;
u32 flags;
void *__ctx[] CRYPTO_MINALIGN_ATTR;
};
#define SHASH_DESC_ON_STACK(shash, ctx) \
char __##shash##_desc[sizeof(struct shash_desc) + \
crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
/**
* 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
* @digestsize: see struct ahash_alg
* @statesize: see struct ahash_alg
* @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
* @base: internally used
*/
struct shash_alg {
int (*init)(struct shash_desc *desc);
int (*update)(struct shash_desc *desc, const u8 *data,
unsigned int len);
int (*final)(struct shash_desc *desc, u8 *out);
int (*finup)(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out);
int (*digest)(struct shash_desc *desc, const u8 *data,
unsigned int len, u8 *out);
int (*export)(struct shash_desc *desc, void *out);
int (*import)(struct shash_desc *desc, const void *in);
int (*setkey)(struct crypto_shash *tfm, const u8 *key,
unsigned int keylen);
unsigned int descsize;
/* These fields must match hash_alg_common. */
unsigned int digestsize
__attribute__ ((aligned(__alignof__(struct hash_alg_common))));
unsigned int statesize;
struct crypto_alg base;
};
struct crypto_ahash {
int (*init)(struct ahash_request *req);
int (*update)(struct ahash_request *req);
int (*final)(struct ahash_request *req);
int (*finup)(struct ahash_request *req);
int (*digest)(struct ahash_request *req);
int (*export)(struct ahash_request *req, void *out);
int (*import)(struct ahash_request *req, const void *in);
int (*setkey)(struct crypto_ahash *tfm, const u8 *key,
unsigned int keylen);
unsigned int reqsize;
bool has_setkey;
struct crypto_tfm base;
};
struct crypto_shash {
unsigned int descsize;
struct crypto_tfm base;
};
/**
* 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_ABLKCIPHER API applies here as well.
*/
static inline struct crypto_ahash *__crypto_ahash_cast(struct crypto_tfm *tfm)
{
return container_of(tfm, struct crypto_ahash, base);
}
/**
* 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);
static inline struct crypto_tfm *crypto_ahash_tfm(struct crypto_ahash *tfm)
{
return &tfm->base;
}
/**
* crypto_free_ahash() - zeroize and free the ahash handle
* @tfm: cipher handle to be freed
*/
static inline void crypto_free_ahash(struct crypto_ahash *tfm)
{
crypto_destroy_tfm(tfm, crypto_ahash_tfm(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)
{
return crypto_tfm_alg_name(crypto_ahash_tfm(tfm));
}
static inline const char *crypto_ahash_driver_name(struct crypto_ahash *tfm)
{
return crypto_tfm_alg_driver_name(crypto_ahash_tfm(tfm));
}
static inline unsigned int crypto_ahash_alignmask(
struct crypto_ahash *tfm)
{
return crypto_tfm_alg_alignmask(crypto_ahash_tfm(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)
{
return crypto_tfm_alg_blocksize(crypto_ahash_tfm(tfm));
}
static inline struct hash_alg_common *__crypto_hash_alg_common(
struct crypto_alg *alg)
{
return container_of(alg, struct hash_alg_common, base);
}
static inline struct hash_alg_common *crypto_hash_alg_common(
struct crypto_ahash *tfm)
{
return __crypto_hash_alg_common(crypto_ahash_tfm(tfm)->__crt_alg);
}
/**
* 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)
{
return crypto_hash_alg_common(tfm)->digestsize;
}
/**
* 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)
{
return crypto_hash_alg_common(tfm)->statesize;
}
static inline u32 crypto_ahash_get_flags(struct crypto_ahash *tfm)
{
return crypto_tfm_get_flags(crypto_ahash_tfm(tfm));
}
static inline void crypto_ahash_set_flags(struct crypto_ahash *tfm, u32 flags)
{
crypto_tfm_set_flags(crypto_ahash_tfm(tfm), flags);
}
static inline void crypto_ahash_clear_flags(struct crypto_ahash *tfm, u32 flags)
{
crypto_tfm_clear_flags(crypto_ahash_tfm(tfm), 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)
{
return __crypto_ahash_cast(req->base.tfm);
}
/**
* 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)
{
return tfm->reqsize;
}
static inline void *ahash_request_ctx(struct ahash_request *req)
{
return req->__ctx;
}
/**
* 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);
static inline bool crypto_ahash_has_setkey(struct crypto_ahash *tfm)
{
return tfm->has_setkey;
}
/**
* 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_shash_final. The parameters have the same
* meaning as discussed for those separate functions.
*
* Return: 0 if the message digest creation was successful; < 0 if an error
* occurred
*/
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 creation was successful; < 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: 0 if the message digest creation was successful; < 0 if an error
* occurred
*/
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
*/
static inline int crypto_ahash_export(struct ahash_request *req, void *out)
{
return crypto_ahash_reqtfm(req)->export(req, 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
*/
static inline int crypto_ahash_import(struct ahash_request *req, const void *in)
{
return crypto_ahash_reqtfm(req)->import(req, 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: 0 if the message digest initialization was successful; < 0 if an
* error occurred
*/
static inline int crypto_ahash_init(struct ahash_request *req)
{
return crypto_ahash_reqtfm(req)->init(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: 0 if the message digest update was successful; < 0 if an error
* occurred
*/
static inline int crypto_ahash_update(struct ahash_request *req)
{
return crypto_ahash_reqtfm(req)->update(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)
{
req->base.tfm = crypto_ahash_tfm(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(
struct crypto_ahash *tfm, gfp_t gfp)
{
struct ahash_request *req;
req = kmalloc(sizeof(struct ahash_request) +
crypto_ahash_reqsize(tfm), gfp);
if (likely(req))
ahash_request_set_tfm(req, tfm);
return req;
}
/**
* 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)
{
kzfree(req);
}
static inline void ahash_request_zero(struct ahash_request *req)
{
memzero_explicit(req, sizeof(*req) +
crypto_ahash_reqsize(crypto_ahash_reqtfm(req)));
}
static inline struct ahash_request *ahash_request_cast(
struct crypto_async_request *req)
{
return container_of(req, struct ahash_request, base);
}
/**
* 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)
{
req->base.complete = compl;
req->base.data = data;
req->base.flags = flags;
}
/**
* 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)
{
req->src = src;
req->nbytes = nbytes;
req->result = result;
}
/**
* 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 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);
static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
{
return &tfm->base;
}
/**
* crypto_free_shash() - zeroize and free the message digest handle
* @tfm: cipher handle to be freed
*/
static inline void crypto_free_shash(struct crypto_shash *tfm)
{
crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
}
static inline const char *crypto_shash_alg_name(struct crypto_shash *tfm)
{
return crypto_tfm_alg_name(crypto_shash_tfm(tfm));
}
static inline const char *crypto_shash_driver_name(struct crypto_shash *tfm)
{
return crypto_tfm_alg_driver_name(crypto_shash_tfm(tfm));
}
static inline unsigned int crypto_shash_alignmask(
struct crypto_shash *tfm)
{
return crypto_tfm_alg_alignmask(crypto_shash_tfm(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)
{
return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
}
static inline struct shash_alg *__crypto_shash_alg(struct crypto_alg *alg)
{
return container_of(alg, struct shash_alg, base);
}
static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
{
return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
}
/**
* 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)
{
return crypto_shash_alg(tfm)->digestsize;
}
static inline unsigned int crypto_shash_statesize(struct crypto_shash *tfm)
{
return crypto_shash_alg(tfm)->statesize;
}
static inline u32 crypto_shash_get_flags(struct crypto_shash *tfm)
{
return crypto_tfm_get_flags(crypto_shash_tfm(tfm));
}
static inline void crypto_shash_set_flags(struct crypto_shash *tfm, u32 flags)
{
crypto_tfm_set_flags(crypto_shash_tfm(tfm), flags);
}
static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
{
crypto_tfm_clear_flags(crypto_shash_tfm(tfm), 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)
{
return tfm->descsize;
}
static inline void *shash_desc_ctx(struct shash_desc *desc)
{
return desc->__ctx;
}
/**
* 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.
*
* 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.
*
* 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_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).
*
* Return: 0 if the export creation was successful; < 0 if an error occurred
*/
static inline int crypto_shash_export(struct shash_desc *desc, void *out)
{
return crypto_shash_alg(desc->tfm)->export(desc, 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.
*
* Return: 0 if the import was successful; < 0 if an error occurred
*/
static inline int crypto_shash_import(struct shash_desc *desc, const void *in)
{
return crypto_shash_alg(desc->tfm)->import(desc, 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.
*
* Return: 0 if the message digest initialization was successful; < 0 if an
* error occurred
*/
static inline int crypto_shash_init(struct shash_desc *desc)
{
return crypto_shash_alg(desc->tfm)->init(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.
*
* 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.
*
* 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.
*
* 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)
{
memzero_explicit(desc,
sizeof(*desc) + crypto_shash_descsize(desc->tfm));
}
#endif /* _CRYPTO_HASH_H */