STRUCT ABLKCIPHER_AL(9)               Programming Interface               STRUCT ABLKCIPHER_AL(9)



NAME
       struct_ablkcipher_alg - asynchronous block cipher definition

SYNOPSIS
       struct ablkcipher_alg {
         int (* setkey) (struct crypto_ablkcipher *tfm, const u8 *key,unsigned int keylen);
         int (* encrypt) (struct ablkcipher_request *req);
         int (* decrypt) (struct ablkcipher_request *req);
         int (* givencrypt) (struct skcipher_givcrypt_request *req);
         int (* givdecrypt) (struct skcipher_givcrypt_request *req);
         const char * geniv;
         unsigned int min_keysize;
         unsigned int max_keysize;
         unsigned int ivsize;
       };

MEMBERS
       setkey
           Set key for the transformation. This function is used to either program a supplied key
           into the hardware or store the key in the transformation context for programming it
           later. Note that this function does modify the transformation context. This function
           can be called multiple times during the existence of the transformation object, so one
           must make sure the key is properly reprogrammed into the hardware. This function is
           also responsible for checking the key length for validity. In case a software fallback
           was put in place in the cra_init call, this function might need to use the fallback if
           the algorithm doesn't support all of the key sizes.

       encrypt
           Encrypt a scatterlist of blocks. This function is used to encrypt the supplied
           scatterlist containing the blocks of data. The crypto API consumer is responsible for
           aligning the entries of the scatterlist properly and making sure the chunks are
           correctly sized. In case a software fallback was put in place in the cra_init call,
           this function might need to use the fallback if the algorithm doesn't support all of
           the key sizes. In case the key was stored in transformation context, the key might
           need to be re-programmed into the hardware in this function. This function shall not
           modify the transformation context, as this function may be called in parallel with the
           same transformation object.

       decrypt
           Decrypt a single block. This is a reverse counterpart to encrypt and the conditions
           are exactly the same.

       givencrypt
           Update the IV for encryption. With this function, a cipher implementation may provide
           the function on how to update the IV for encryption.

       givdecrypt
           Update the IV for decryption. This is the reverse of givencrypt .

       geniv
           The transformation implementation may use an “IV generator” provided by the kernel
           crypto API. Several use cases have a predefined approach how IVs are to be updated.
           For such use cases, the kernel crypto API provides ready-to-use implementations that
           can be referenced with this variable.

       min_keysize
           Minimum key size supported by the transformation. This is the smallest key length
           supported by this transformation algorithm. This must be set to one of the pre-defined
           values as this is not hardware specific. Possible values for this field can be found
           via git grep “_MIN_KEY_SIZE” include/crypto/

       max_keysize
           Maximum key size supported by the transformation. This is the largest key length
           supported by this transformation algorithm. This must be set to one of the pre-defined
           values as this is not hardware specific. Possible values for this field can be found
           via git grep “_MAX_KEY_SIZE” include/crypto/

       ivsize
           IV size applicable for transformation. The consumer must provide an IV of exactly that
           size to perform the encrypt or decrypt operation.

DESCRIPTION
       All fields except givencrypt , givdecrypt , geniv and ivsize are mandatory and must be
       filled.

AUTHORS
       Stephan Mueller <smueller AT chronox.de>
           Author.

       Marek Vasut <marek AT denx.de>
           Author.

COPYRIGHT
Kernel Hackers Manual 4.8.                 January 2017                   STRUCT ABLKCIPHER_AL(9)