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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: **[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.
+ * @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;
+ 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
+ *
+ * If @tfm is a NULL or error pointer, this function does nothing.
+ */
+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);
+
+/**
+ * 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 feeded 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
+ */
+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)
+{
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+
+ if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
+ return -ENOKEY;
+
+ return tfm->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: see crypto_ahash_final()
+ */
+static inline int crypto_ahash_init(struct ahash_request *req)
+{
+ struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
+
+ if (crypto_ahash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
+ return -ENOKEY;
+
+ return tfm->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: see crypto_ahash_final()
+ */
+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
+ *
+ * If @tfm is a NULL or error pointer, this function does nothing.
+ */
+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)
+{
+ struct crypto_shash *tfm = desc->tfm;
+
+ if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
+ return -ENOKEY;
+
+ return crypto_shash_alg(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)
+{
+ struct crypto_shash *tfm = desc->tfm;
+
+ if (crypto_shash_get_flags(tfm) & CRYPTO_TFM_NEED_KEY)
+ return -ENOKEY;
+
+ return crypto_shash_alg(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 */