struct ablkcipher_alg — asynchronous block cipher definition
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;
};
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 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 a single block. This is a reverse counterpart to encrypt
and the conditions are exactly the same.
Update the IV for encryption. With this function, a cipher implementation may provide the function on how to update the IV for encryption.
Update the IV for decryption. This is the reverse of
givencrypt .
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.
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/
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/
IV size applicable for transformation. The consumer must provide an IV of exactly that size to perform the encrypt or decrypt operation.