+/**
+ * struct skcipher_alg - symmetric key cipher definition
+ * @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/
+ * @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.
+ * @init: Initialize the cryptographic transformation object. This function
+ * is used to initialize the cryptographic transformation object.
+ * This function is called only once at the instantiation time, right
+ * after the transformation context was allocated. In case the
+ * cryptographic hardware has some special requirements which need to
+ * be handled by software, this function shall check for the precise
+ * requirement of the transformation and put any software fallbacks
+ * in place.
+ * @exit: Deinitialize the cryptographic transformation object. This is a
+ * counterpart to @init, used to remove various changes set in
+ * @init.
+ * @ivsize: IV size applicable for transformation. The consumer must provide an
+ * IV of exactly that size to perform the encrypt or decrypt operation.
+ * @chunksize: Equal to the block size except for stream ciphers such as
+ * CTR where it is set to the underlying block size.
+ * @base: Definition of a generic crypto algorithm.
+ *
+ * All fields except @ivsize are mandatory and must be filled.
+ */
+struct skcipher_alg {
+ int (*setkey)(struct crypto_skcipher *tfm, const u8 *key,
+ unsigned int keylen);
+ int (*encrypt)(struct skcipher_request *req);
+ int (*decrypt)(struct skcipher_request *req);
+ int (*init)(struct crypto_skcipher *tfm);
+ void (*exit)(struct crypto_skcipher *tfm);