diff options
| -rw-r--r-- | include/crypto/hash.h | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/include/crypto/hash.h b/include/crypto/hash.h index bf458fc272aa..b2c193acc1ab 100644 --- a/include/crypto/hash.h +++ b/include/crypto/hash.h @@ -202,11 +202,35 @@ struct crypto_shash { 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); @@ -215,6 +239,10 @@ 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)); @@ -238,6 +266,16 @@ static inline struct hash_alg_common *crypto_hash_alg_common( 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; @@ -263,12 +301,32 @@ 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 the size of the ahash state size. 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_reqsize(struct crypto_ahash *tfm) { return tfm->reqsize; @@ -279,38 +337,166 @@ 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_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_reqsize). + * + * 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; IS_ERR() is true in case + * of an error, PTR_ERR() returns the error code. + */ static inline struct ahash_request *ahash_request_alloc( struct crypto_ahash *tfm, gfp_t gfp) { @@ -325,6 +511,10 @@ static inline struct ahash_request *ahash_request_alloc( 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); @@ -336,6 +526,31 @@ static inline struct ahash_request *ahash_request_cast( 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, @@ -346,6 +561,19 @@ static inline void ahash_request_set_callback(struct ahash_request *req, 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) |