--- zzzz-none-000/linux-3.10.107/include/linux/crypto.h	2017-06-27 09:49:32.000000000 +0000
+++ scorpion-7490-727/linux-3.10.107/include/linux/crypto.h	2021-02-04 17:41:59.000000000 +0000
@@ -53,6 +53,7 @@
 #define CRYPTO_ALG_TYPE_SHASH		0x00000009
 #define CRYPTO_ALG_TYPE_AHASH		0x0000000a
 #define CRYPTO_ALG_TYPE_RNG		0x0000000c
+#define CRYPTO_ALG_TYPE_AKCIPHER	0x0000000d
 #define CRYPTO_ALG_TYPE_PCOMPRESS	0x0000000f
 
 #define CRYPTO_ALG_TYPE_HASH_MASK	0x0000000e
@@ -95,6 +96,17 @@
 #define CRYPTO_ALG_KERN_DRIVER_ONLY	0x00001000
 
 /*
+ * Mark a cipher as a service implementation only usable by another
+ * cipher and never by a normal user of the kernel crypto API
+ */
+#define CRYPTO_ALG_INTERNAL		0x00002000
+
+/*
+ * Set this flag if algorithm does not support SG list transforms
+ */
+#define CRYPTO_ALG_NOSUPP_SG		0x00004000
+
+/*
  * Transform masks and values (for crt_flags).
  */
 #define CRYPTO_TFM_REQ_MASK		0x000fff00
@@ -129,17 +141,21 @@
 struct scatterlist;
 struct crypto_ablkcipher;
 struct crypto_async_request;
-struct crypto_aead;
 struct crypto_blkcipher;
 struct crypto_hash;
-struct crypto_rng;
 struct crypto_tfm;
 struct crypto_type;
-struct aead_givcrypt_request;
 struct skcipher_givcrypt_request;
 
 typedef void (*crypto_completion_t)(struct crypto_async_request *req, int err);
 
+/**
+ * DOC: Block Cipher Context Data Structures
+ *
+ * These data structures define the operating context for each block cipher
+ * type.
+ */
+
 struct crypto_async_request {
 	struct list_head list;
 	crypto_completion_t complete;
@@ -162,32 +178,6 @@
 	void *__ctx[] CRYPTO_MINALIGN_ATTR;
 };
 
-/**
- *	struct aead_request - AEAD request
- *	@base: Common attributes for async crypto requests
- *	@assoclen: Length in bytes of associated data for authentication
- *	@cryptlen: Length of data to be encrypted or decrypted
- *	@iv: Initialisation vector
- *	@assoc: Associated data
- *	@src: Source data
- *	@dst: Destination data
- *	@__ctx: Start of private context data
- */
-struct aead_request {
-	struct crypto_async_request base;
-
-	unsigned int assoclen;
-	unsigned int cryptlen;
-
-	u8 *iv;
-
-	struct scatterlist *assoc;
-	struct scatterlist *src;
-	struct scatterlist *dst;
-
-	void *__ctx[] CRYPTO_MINALIGN_ATTR;
-};
-
 struct blkcipher_desc {
 	struct crypto_blkcipher *tfm;
 	void *info;
@@ -207,9 +197,63 @@
 	u32 flags;
 };
 
-/*
- * Algorithms: modular crypto algorithm implementations, managed
- * via crypto_register_alg() and crypto_unregister_alg().
+/**
+ * DOC: Block Cipher Algorithm Definitions
+ *
+ * These data structures define modular crypto algorithm implementations,
+ * managed via crypto_register_alg() and crypto_unregister_alg().
+ */
+
+/**
+ * struct ablkcipher_alg - asynchronous block 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.
+ * @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.
+ * @ivsize: IV size applicable for transformation. The consumer must provide an
+ *	    IV of exactly that size to perform the encrypt or decrypt operation.
+ *
+ * All fields except @givencrypt , @givdecrypt , @geniv and @ivsize are
+ * mandatory and must be filled.
  */
 struct ablkcipher_alg {
 	int (*setkey)(struct crypto_ablkcipher *tfm, const u8 *key,
@@ -226,21 +270,18 @@
 	unsigned int ivsize;
 };
 
-struct aead_alg {
-	int (*setkey)(struct crypto_aead *tfm, const u8 *key,
-	              unsigned int keylen);
-	int (*setauthsize)(struct crypto_aead *tfm, unsigned int authsize);
-	int (*encrypt)(struct aead_request *req);
-	int (*decrypt)(struct aead_request *req);
-	int (*givencrypt)(struct aead_givcrypt_request *req);
-	int (*givdecrypt)(struct aead_givcrypt_request *req);
-
-	const char *geniv;
-
-	unsigned int ivsize;
-	unsigned int maxauthsize;
-};
-
+/**
+ * struct blkcipher_alg - synchronous block cipher definition
+ * @min_keysize: see struct ablkcipher_alg
+ * @max_keysize: see struct ablkcipher_alg
+ * @setkey: see struct ablkcipher_alg
+ * @encrypt: see struct ablkcipher_alg
+ * @decrypt: see struct ablkcipher_alg
+ * @geniv: see struct ablkcipher_alg
+ * @ivsize: see struct ablkcipher_alg
+ *
+ * All fields except @geniv and @ivsize are mandatory and must be filled.
+ */
 struct blkcipher_alg {
 	int (*setkey)(struct crypto_tfm *tfm, const u8 *key,
 	              unsigned int keylen);
@@ -258,6 +299,53 @@
 	unsigned int ivsize;
 };
 
+/**
+ * struct cipher_alg - single-block symmetric ciphers definition
+ * @cia_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/
+ * @cia_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/
+ * @cia_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.
+ * @cia_encrypt: Encrypt a single block. This function is used to encrypt a
+ *		 single block of data, which must be @cra_blocksize big. This
+ *		 always operates on a full @cra_blocksize and it is not possible
+ *		 to encrypt a block of smaller size. The supplied buffers must
+ *		 therefore also be at least of @cra_blocksize size. Both the
+ *		 input and output buffers are always aligned to @cra_alignmask.
+ *		 In case either of the input or output buffer supplied by user
+ *		 of the crypto API is not aligned to @cra_alignmask, the crypto
+ *		 API will re-align the buffers. The re-alignment means that a
+ *		 new buffer will be allocated, the data will be copied into the
+ *		 new buffer, then the processing will happen on the new buffer,
+ *		 then the data will be copied back into the original buffer and
+ *		 finally the new buffer will be freed. 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.
+ * @cia_decrypt: Decrypt a single block. This is a reverse counterpart to
+ *		 @cia_encrypt, and the conditions are exactly the same.
+ *
+ * All fields are mandatory and must be filled.
+ */
 struct cipher_alg {
 	unsigned int cia_min_keysize;
 	unsigned int cia_max_keysize;
@@ -274,22 +362,87 @@
 			      unsigned int slen, u8 *dst, unsigned int *dlen);
 };
 
-struct rng_alg {
-	int (*rng_make_random)(struct crypto_rng *tfm, u8 *rdata,
-			       unsigned int dlen);
-	int (*rng_reset)(struct crypto_rng *tfm, u8 *seed, unsigned int slen);
-
-	unsigned int seedsize;
-};
-
 
 #define cra_ablkcipher	cra_u.ablkcipher
-#define cra_aead	cra_u.aead
 #define cra_blkcipher	cra_u.blkcipher
 #define cra_cipher	cra_u.cipher
 #define cra_compress	cra_u.compress
-#define cra_rng		cra_u.rng
 
+/**
+ * struct crypto_alg - definition of a cryptograpic cipher algorithm
+ * @cra_flags: Flags describing this transformation. See include/linux/crypto.h
+ *	       CRYPTO_ALG_* flags for the flags which go in here. Those are
+ *	       used for fine-tuning the description of the transformation
+ *	       algorithm.
+ * @cra_blocksize: Minimum block size of this transformation. The size in bytes
+ *		   of the smallest possible unit which can be transformed with
+ *		   this algorithm. The users must respect this value.
+ *		   In case of HASH transformation, it is possible for a smaller
+ *		   block than @cra_blocksize to be passed to the crypto API for
+ *		   transformation, in case of any other transformation type, an
+ * 		   error will be returned upon any attempt to transform smaller
+ *		   than @cra_blocksize chunks.
+ * @cra_ctxsize: Size of the operational context of the transformation. This
+ *		 value informs the kernel crypto API about the memory size
+ *		 needed to be allocated for the transformation context.
+ * @cra_alignmask: Alignment mask for the input and output data buffer. The data
+ *		   buffer containing the input data for the algorithm must be
+ *		   aligned to this alignment mask. The data buffer for the
+ *		   output data must be aligned to this alignment mask. Note that
+ *		   the Crypto API will do the re-alignment in software, but
+ *		   only under special conditions and there is a performance hit.
+ *		   The re-alignment happens at these occasions for different
+ *		   @cra_u types: cipher -- For both input data and output data
+ *		   buffer; ahash -- For output hash destination buf; shash --
+ *		   For output hash destination buf.
+ *		   This is needed on hardware which is flawed by design and
+ *		   cannot pick data from arbitrary addresses.
+ * @cra_priority: Priority of this transformation implementation. In case
+ *		  multiple transformations with same @cra_name are available to
+ *		  the Crypto API, the kernel will use the one with highest
+ *		  @cra_priority.
+ * @cra_name: Generic name (usable by multiple implementations) of the
+ *	      transformation algorithm. This is the name of the transformation
+ *	      itself. This field is used by the kernel when looking up the
+ *	      providers of particular transformation.
+ * @cra_driver_name: Unique name of the transformation provider. This is the
+ *		     name of the provider of the transformation. This can be any
+ *		     arbitrary value, but in the usual case, this contains the
+ *		     name of the chip or provider and the name of the
+ *		     transformation algorithm.
+ * @cra_type: Type of the cryptographic transformation. This is a pointer to
+ *	      struct crypto_type, which implements callbacks common for all
+ *	      transformation types. There are multiple options:
+ *	      &crypto_blkcipher_type, &crypto_ablkcipher_type,
+ *	      &crypto_ahash_type, &crypto_rng_type.
+ *	      This field might be empty. In that case, there are no common
+ *	      callbacks. This is the case for: cipher, compress, shash.
+ * @cra_u: Callbacks implementing the transformation. This is a union of
+ *	   multiple structures. Depending on the type of transformation selected
+ *	   by @cra_type and @cra_flags above, the associated structure must be
+ *	   filled with callbacks. This field might be empty. This is the case
+ *	   for ahash, shash.
+ * @cra_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.
+ * @cra_exit: Deinitialize the cryptographic transformation object. This is a
+ *	      counterpart to @cra_init, used to remove various changes set in
+ *	      @cra_init.
+ * @cra_module: Owner of this transformation implementation. Set to THIS_MODULE
+ * @cra_list: internally used
+ * @cra_users: internally used
+ * @cra_refcnt: internally used
+ * @cra_destroy: internally used
+ *
+ * The struct crypto_alg describes a generic Crypto API algorithm and is common
+ * for all of the transformations. Any variable not documented here shall not
+ * be used by a cipher implementation as it is internal to the Crypto API.
+ */
 struct crypto_alg {
 	struct list_head cra_list;
 	struct list_head cra_users;
@@ -309,11 +462,9 @@
 
 	union {
 		struct ablkcipher_alg ablkcipher;
-		struct aead_alg aead;
 		struct blkcipher_alg blkcipher;
 		struct cipher_alg cipher;
 		struct compress_alg compress;
-		struct rng_alg rng;
 	} cra_u;
 
 	int (*cra_init)(struct crypto_tfm *tfm);
@@ -321,7 +472,7 @@
 	void (*cra_destroy)(struct crypto_alg *alg);
 	
 	struct module *cra_module;
-};
+} CRYPTO_MINALIGN_ATTR;
 
 /*
  * Algorithm registration interface.
@@ -354,22 +505,6 @@
 
 	unsigned int ivsize;
 	unsigned int reqsize;
-	bool has_setkey;
-};
-
-struct aead_tfm {
-	int (*setkey)(struct crypto_aead *tfm, const u8 *key,
-	              unsigned int keylen);
-	int (*encrypt)(struct aead_request *req);
-	int (*decrypt)(struct aead_request *req);
-	int (*givencrypt)(struct aead_givcrypt_request *req);
-	int (*givdecrypt)(struct aead_givcrypt_request *req);
-
-	struct crypto_aead *base;
-
-	unsigned int ivsize;
-	unsigned int authsize;
-	unsigned int reqsize;
 };
 
 struct blkcipher_tfm {
@@ -410,19 +545,11 @@
 	                      u8 *dst, unsigned int *dlen);
 };
 
-struct rng_tfm {
-	int (*rng_gen_random)(struct crypto_rng *tfm, u8 *rdata,
-			      unsigned int dlen);
-	int (*rng_reset)(struct crypto_rng *tfm, u8 *seed, unsigned int slen);
-};
-
 #define crt_ablkcipher	crt_u.ablkcipher
-#define crt_aead	crt_u.aead
 #define crt_blkcipher	crt_u.blkcipher
 #define crt_cipher	crt_u.cipher
 #define crt_hash	crt_u.hash
 #define crt_compress	crt_u.compress
-#define crt_rng		crt_u.rng
 
 struct crypto_tfm {
 
@@ -430,12 +557,10 @@
 	
 	union {
 		struct ablkcipher_tfm ablkcipher;
-		struct aead_tfm aead;
 		struct blkcipher_tfm blkcipher;
 		struct cipher_tfm cipher;
 		struct hash_tfm hash;
 		struct compress_tfm compress;
-		struct rng_tfm rng;
 	} crt_u;
 
 	void (*exit)(struct crypto_tfm *tfm);
@@ -449,10 +574,6 @@
 	struct crypto_tfm base;
 };
 
-struct crypto_aead {
-	struct crypto_tfm base;
-};
-
 struct crypto_blkcipher {
 	struct crypto_tfm base;
 };
@@ -469,10 +590,6 @@
 	struct crypto_tfm base;
 };
 
-struct crypto_rng {
-	struct crypto_tfm base;
-};
-
 enum {
 	CRYPTOA_UNSPEC,
 	CRYPTOA_ALG,
@@ -536,6 +653,11 @@
 	return tfm->__crt_alg->cra_flags & CRYPTO_ALG_TYPE_MASK;
 }
 
+static inline u32 crypto_tfm_alg_flags(struct crypto_tfm *tfm)
+{
+	return tfm->__crt_alg->cra_flags & ~CRYPTO_ALG_TYPE_MASK;
+}
+
 static inline unsigned int crypto_tfm_alg_blocksize(struct crypto_tfm *tfm)
 {
 	return tfm->__crt_alg->cra_blocksize;
@@ -595,6 +717,50 @@
 	return mask;
 }
 
+/**
+ * DOC: Asynchronous Block Cipher API
+ *
+ * Asynchronous block cipher API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_ABLKCIPHER (listed as type "ablkcipher" in /proc/crypto).
+ *
+ * Asynchronous cipher operations imply that the function invocation for a
+ * cipher request returns immediately before the completion of the operation.
+ * The cipher request is scheduled as a separate kernel thread and therefore
+ * load-balanced on the different CPUs via the process scheduler. To allow
+ * the kernel crypto API to inform the caller about the completion of a cipher
+ * request, the caller must provide a callback function. That function is
+ * invoked with the cipher handle when the request completes.
+ *
+ * To support the asynchronous operation, additional information than just the
+ * cipher handle must be supplied to the kernel crypto API. That additional
+ * information is given by filling in the ablkcipher_request data structure.
+ *
+ * For the asynchronous block cipher API, the state is maintained with the tfm
+ * cipher handle. A single tfm can be used across multiple calls and in
+ * parallel. For asynchronous block cipher calls, context data supplied and
+ * only used by the caller can be referenced the request data structure in
+ * addition to the IV used for the cipher request. The maintenance of such
+ * state information would be important for a crypto driver implementer to
+ * have, because when calling the callback function upon completion of the
+ * cipher operation, that callback function may need some information about
+ * which operation just finished if it invoked multiple in parallel. This
+ * state information is unused by the kernel crypto API.
+ */
+
+/**
+ * crypto_alloc_ablkcipher() - allocate asynchronous block cipher handle
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	      ablkcipher cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Allocate a cipher handle for an ablkcipher. The returned struct
+ * crypto_ablkcipher is the cipher handle that is required for any subsequent
+ * API invocation for that ablkcipher.
+ *
+ * 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_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name,
 						  u32 type, u32 mask);
 
@@ -604,11 +770,25 @@
 	return &tfm->base;
 }
 
+/**
+ * crypto_free_ablkcipher() - zeroize and free cipher handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_ablkcipher(struct crypto_ablkcipher *tfm)
 {
 	crypto_free_tfm(crypto_ablkcipher_tfm(tfm));
 }
 
+/**
+ * crypto_has_ablkcipher() - Search for the availability of an ablkcipher.
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	      ablkcipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Return: true when the ablkcipher is known to the kernel crypto API; false
+ *	   otherwise
+ */
 static inline int crypto_has_ablkcipher(const char *alg_name, u32 type,
 					u32 mask)
 {
@@ -622,12 +802,31 @@
 	return &crypto_ablkcipher_tfm(tfm)->crt_ablkcipher;
 }
 
+/**
+ * crypto_ablkcipher_ivsize() - obtain IV size
+ * @tfm: cipher handle
+ *
+ * The size of the IV for the ablkcipher referenced by the cipher handle is
+ * returned. This IV size may be zero if the cipher does not need an IV.
+ *
+ * Return: IV size in bytes
+ */
 static inline unsigned int crypto_ablkcipher_ivsize(
 	struct crypto_ablkcipher *tfm)
 {
 	return crypto_ablkcipher_crt(tfm)->ivsize;
 }
 
+/**
+ * crypto_ablkcipher_blocksize() - obtain block size of cipher
+ * @tfm: cipher handle
+ *
+ * The block size for the ablkcipher referenced with the cipher handle is
+ * returned. The caller may use that information to allocate appropriate
+ * memory for the data returned by the encryption or decryption operation
+ *
+ * Return: block size of cipher
+ */
 static inline unsigned int crypto_ablkcipher_blocksize(
 	struct crypto_ablkcipher *tfm)
 {
@@ -657,6 +856,22 @@
 	crypto_tfm_clear_flags(crypto_ablkcipher_tfm(tfm), flags);
 }
 
+/**
+ * crypto_ablkcipher_setkey() - set key for cipher
+ * @tfm: cipher handle
+ * @key: buffer holding the key
+ * @keylen: length of the key in bytes
+ *
+ * The caller provided key is set for the ablkcipher referenced by the cipher
+ * handle.
+ *
+ * Note, the key length determines the cipher type. Many block ciphers implement
+ * different cipher modes depending on the key size, such as AES-128 vs AES-192
+ * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
+ * is performed.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 static inline int crypto_ablkcipher_setkey(struct crypto_ablkcipher *tfm,
 					   const u8 *key, unsigned int keylen)
 {
@@ -665,19 +880,32 @@
 	return crt->setkey(crt->base, key, keylen);
 }
 
-static inline bool crypto_ablkcipher_has_setkey(struct crypto_ablkcipher *tfm)
-{
-	struct ablkcipher_tfm *crt = crypto_ablkcipher_crt(tfm);
-
-	return crt->has_setkey;
-}
-
+/**
+ * crypto_ablkcipher_reqtfm() - obtain cipher handle from request
+ * @req: ablkcipher_request out of which the cipher handle is to be obtained
+ *
+ * Return the crypto_ablkcipher handle when furnishing an ablkcipher_request
+ * data structure.
+ *
+ * Return: crypto_ablkcipher handle
+ */
 static inline struct crypto_ablkcipher *crypto_ablkcipher_reqtfm(
 	struct ablkcipher_request *req)
 {
 	return __crypto_ablkcipher_cast(req->base.tfm);
 }
 
+/**
+ * crypto_ablkcipher_encrypt() - encrypt plaintext
+ * @req: reference to the ablkcipher_request handle that holds all information
+ *	 needed to perform the cipher operation
+ *
+ * Encrypt plaintext data using the ablkcipher_request handle. That data
+ * structure and how it is filled with data is discussed with the
+ * ablkcipher_request_* functions.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_ablkcipher_encrypt(struct ablkcipher_request *req)
 {
 	struct ablkcipher_tfm *crt =
@@ -685,6 +913,17 @@
 	return crt->encrypt(req);
 }
 
+/**
+ * crypto_ablkcipher_decrypt() - decrypt ciphertext
+ * @req: reference to the ablkcipher_request handle that holds all information
+ *	 needed to perform the cipher operation
+ *
+ * Decrypt ciphertext data using the ablkcipher_request handle. That data
+ * structure and how it is filled with data is discussed with the
+ * ablkcipher_request_* functions.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_ablkcipher_decrypt(struct ablkcipher_request *req)
 {
 	struct ablkcipher_tfm *crt =
@@ -692,12 +931,37 @@
 	return crt->decrypt(req);
 }
 
+/**
+ * DOC: Asynchronous Cipher Request Handle
+ *
+ * The ablkcipher_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 ablkcipher_request instances), pointer
+ * to plaintext and ciphertext, asynchronous callback function, etc. It acts
+ * as a handle to the ablkcipher_request_* API calls in a similar way as
+ * ablkcipher handle to the crypto_ablkcipher_* API calls.
+ */
+
+/**
+ * crypto_ablkcipher_reqsize() - obtain size of the request data structure
+ * @tfm: cipher handle
+ *
+ * Return: number of bytes
+ */
 static inline unsigned int crypto_ablkcipher_reqsize(
 	struct crypto_ablkcipher *tfm)
 {
 	return crypto_ablkcipher_crt(tfm)->reqsize;
 }
 
+/**
+ * ablkcipher_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 ablkcipher handle in the request
+ * data structure with a different one.
+ */
 static inline void ablkcipher_request_set_tfm(
 	struct ablkcipher_request *req, struct crypto_ablkcipher *tfm)
 {
@@ -710,6 +974,18 @@
 	return container_of(req, struct ablkcipher_request, base);
 }
 
+/**
+ * ablkcipher_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 ablkcipher
+ * encrypt and decrypt API calls. During the allocation, the provided ablkcipher
+ * 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 ablkcipher_request *ablkcipher_request_alloc(
 	struct crypto_ablkcipher *tfm, gfp_t gfp)
 {
@@ -724,20 +1000,65 @@
 	return req;
 }
 
+/**
+ * ablkcipher_request_free() - zeroize and free request data structure
+ * @req: request data structure cipher handle to be freed
+ */
 static inline void ablkcipher_request_free(struct ablkcipher_request *req)
 {
 	kzfree(req);
 }
 
+/**
+ * ablkcipher_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 ablkcipher_request handle and
+ * must comply with the following template
+ *
+ *	void callback_function(struct crypto_async_request *req, int error)
+ */
 static inline void ablkcipher_request_set_callback(
 	struct ablkcipher_request *req,
-	u32 flags, crypto_completion_t complete, void *data)
+	u32 flags, crypto_completion_t compl, void *data)
 {
-	req->base.complete = complete;
+	req->base.complete = compl;
 	req->base.data = data;
 	req->base.flags = flags;
 }
 
+/**
+ * ablkcipher_request_set_crypt() - set data buffers
+ * @req: request handle
+ * @src: source scatter / gather list
+ * @dst: destination scatter / gather list
+ * @nbytes: number of bytes to process from @src
+ * @iv: IV for the cipher operation which must comply with the IV size defined
+ *      by crypto_ablkcipher_ivsize
+ *
+ * This function allows setting of the source data and destination data
+ * scatter / gather lists.
+ *
+ * For encryption, the source is treated as the plaintext and the
+ * destination is the ciphertext. For a decryption operation, the use is
+ * reversed - the source is the ciphertext and the destination is the plaintext.
+ */
 static inline void ablkcipher_request_set_crypt(
 	struct ablkcipher_request *req,
 	struct scatterlist *src, struct scatterlist *dst,
@@ -749,145 +1070,35 @@
 	req->info = iv;
 }
 
-static inline struct crypto_aead *__crypto_aead_cast(struct crypto_tfm *tfm)
-{
-	return (struct crypto_aead *)tfm;
-}
-
-struct crypto_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask);
-
-static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm)
-{
-	return &tfm->base;
-}
-
-static inline void crypto_free_aead(struct crypto_aead *tfm)
-{
-	crypto_free_tfm(crypto_aead_tfm(tfm));
-}
-
-static inline struct aead_tfm *crypto_aead_crt(struct crypto_aead *tfm)
-{
-	return &crypto_aead_tfm(tfm)->crt_aead;
-}
-
-static inline unsigned int crypto_aead_ivsize(struct crypto_aead *tfm)
-{
-	return crypto_aead_crt(tfm)->ivsize;
-}
-
-static inline unsigned int crypto_aead_authsize(struct crypto_aead *tfm)
-{
-	return crypto_aead_crt(tfm)->authsize;
-}
-
-static inline unsigned int crypto_aead_blocksize(struct crypto_aead *tfm)
-{
-	return crypto_tfm_alg_blocksize(crypto_aead_tfm(tfm));
-}
-
-static inline unsigned int crypto_aead_alignmask(struct crypto_aead *tfm)
-{
-	return crypto_tfm_alg_alignmask(crypto_aead_tfm(tfm));
-}
-
-static inline u32 crypto_aead_get_flags(struct crypto_aead *tfm)
-{
-	return crypto_tfm_get_flags(crypto_aead_tfm(tfm));
-}
-
-static inline void crypto_aead_set_flags(struct crypto_aead *tfm, u32 flags)
-{
-	crypto_tfm_set_flags(crypto_aead_tfm(tfm), flags);
-}
-
-static inline void crypto_aead_clear_flags(struct crypto_aead *tfm, u32 flags)
-{
-	crypto_tfm_clear_flags(crypto_aead_tfm(tfm), flags);
-}
-
-static inline int crypto_aead_setkey(struct crypto_aead *tfm, const u8 *key,
-				     unsigned int keylen)
-{
-	struct aead_tfm *crt = crypto_aead_crt(tfm);
-
-	return crt->setkey(crt->base, key, keylen);
-}
-
-int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize);
-
-static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req)
-{
-	return __crypto_aead_cast(req->base.tfm);
-}
-
-static inline int crypto_aead_encrypt(struct aead_request *req)
-{
-	return crypto_aead_crt(crypto_aead_reqtfm(req))->encrypt(req);
-}
-
-static inline int crypto_aead_decrypt(struct aead_request *req)
-{
-	return crypto_aead_crt(crypto_aead_reqtfm(req))->decrypt(req);
-}
-
-static inline unsigned int crypto_aead_reqsize(struct crypto_aead *tfm)
-{
-	return crypto_aead_crt(tfm)->reqsize;
-}
-
-static inline void aead_request_set_tfm(struct aead_request *req,
-					struct crypto_aead *tfm)
-{
-	req->base.tfm = crypto_aead_tfm(crypto_aead_crt(tfm)->base);
-}
-
-static inline struct aead_request *aead_request_alloc(struct crypto_aead *tfm,
-						      gfp_t gfp)
-{
-	struct aead_request *req;
-
-	req = kmalloc(sizeof(*req) + crypto_aead_reqsize(tfm), gfp);
-
-	if (likely(req))
-		aead_request_set_tfm(req, tfm);
-
-	return req;
-}
-
-static inline void aead_request_free(struct aead_request *req)
-{
-	kzfree(req);
-}
-
-static inline void aead_request_set_callback(struct aead_request *req,
-					     u32 flags,
-					     crypto_completion_t complete,
-					     void *data)
-{
-	req->base.complete = complete;
-	req->base.data = data;
-	req->base.flags = flags;
-}
-
-static inline void aead_request_set_crypt(struct aead_request *req,
-					  struct scatterlist *src,
-					  struct scatterlist *dst,
-					  unsigned int cryptlen, u8 *iv)
-{
-	req->src = src;
-	req->dst = dst;
-	req->cryptlen = cryptlen;
-	req->iv = iv;
-}
-
-static inline void aead_request_set_assoc(struct aead_request *req,
-					  struct scatterlist *assoc,
-					  unsigned int assoclen)
-{
-	req->assoc = assoc;
-	req->assoclen = assoclen;
-}
+/**
+ * DOC: Synchronous Block Cipher API
+ *
+ * The synchronous block cipher API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_BLKCIPHER (listed as type "blkcipher" in /proc/crypto)
+ *
+ * Synchronous calls, have a context in the tfm. But since a single tfm can be
+ * used in multiple calls and in parallel, this info should not be changeable
+ * (unless a lock is used). This applies, for example, to the symmetric key.
+ * However, the IV is changeable, so there is an iv field in blkcipher_tfm
+ * structure for synchronous blkcipher api. So, its the only state info that can
+ * be kept for synchronous calls without using a big lock across a tfm.
+ *
+ * The block cipher API allows the use of a complete cipher, i.e. a cipher
+ * consisting of a template (a block chaining mode) and a single block cipher
+ * primitive (e.g. AES).
+ *
+ * The plaintext data buffer and the ciphertext data buffer are pointed to
+ * by using scatter/gather lists. The cipher operation is performed
+ * on all segments of the provided scatter/gather lists.
+ *
+ * The kernel crypto API supports a cipher operation "in-place" which means that
+ * the caller may provide the same scatter/gather list for the plaintext and
+ * cipher text. After the completion of the cipher operation, the plaintext
+ * data is replaced with the ciphertext data in case of an encryption and vice
+ * versa for a decryption. The caller must ensure that the scatter/gather lists
+ * for the output data point to sufficiently large buffers, i.e. multiples of
+ * the block size of the cipher.
+ */
 
 static inline struct crypto_blkcipher *__crypto_blkcipher_cast(
 	struct crypto_tfm *tfm)
@@ -902,6 +1113,20 @@
 	return __crypto_blkcipher_cast(tfm);
 }
 
+/**
+ * crypto_alloc_blkcipher() - allocate synchronous block cipher handle
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	      blkcipher cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Allocate a cipher handle for a block cipher. The returned struct
+ * crypto_blkcipher is the cipher handle that is required for any subsequent
+ * API invocation for that block cipher.
+ *
+ * Return: allocated cipher handle in case of success; IS_ERR() is true in case
+ *	   of an error, PTR_ERR() returns the error code.
+ */
 static inline struct crypto_blkcipher *crypto_alloc_blkcipher(
 	const char *alg_name, u32 type, u32 mask)
 {
@@ -918,11 +1143,25 @@
 	return &tfm->base;
 }
 
+/**
+ * crypto_free_blkcipher() - zeroize and free the block cipher handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_blkcipher(struct crypto_blkcipher *tfm)
 {
 	crypto_free_tfm(crypto_blkcipher_tfm(tfm));
 }
 
+/**
+ * crypto_has_blkcipher() - Search for the availability of a block cipher
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	      block cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Return: true when the block cipher is known to the kernel crypto API; false
+ *	   otherwise
+ */
 static inline int crypto_has_blkcipher(const char *alg_name, u32 type, u32 mask)
 {
 	type &= ~CRYPTO_ALG_TYPE_MASK;
@@ -932,6 +1171,12 @@
 	return crypto_has_alg(alg_name, type, mask);
 }
 
+/**
+ * crypto_blkcipher_name() - return the name / cra_name from the cipher handle
+ * @tfm: cipher handle
+ *
+ * Return: The character string holding the name of the cipher
+ */
 static inline const char *crypto_blkcipher_name(struct crypto_blkcipher *tfm)
 {
 	return crypto_tfm_alg_name(crypto_blkcipher_tfm(tfm));
@@ -949,11 +1194,30 @@
 	return &crypto_blkcipher_tfm(tfm)->__crt_alg->cra_blkcipher;
 }
 
+/**
+ * crypto_blkcipher_ivsize() - obtain IV size
+ * @tfm: cipher handle
+ *
+ * The size of the IV for the block cipher referenced by the cipher handle is
+ * returned. This IV size may be zero if the cipher does not need an IV.
+ *
+ * Return: IV size in bytes
+ */
 static inline unsigned int crypto_blkcipher_ivsize(struct crypto_blkcipher *tfm)
 {
 	return crypto_blkcipher_alg(tfm)->ivsize;
 }
 
+/**
+ * crypto_blkcipher_blocksize() - obtain block size of cipher
+ * @tfm: cipher handle
+ *
+ * The block size for the block cipher referenced with the cipher handle is
+ * returned. The caller may use that information to allocate appropriate
+ * memory for the data returned by the encryption or decryption operation.
+ *
+ * Return: block size of cipher
+ */
 static inline unsigned int crypto_blkcipher_blocksize(
 	struct crypto_blkcipher *tfm)
 {
@@ -983,6 +1247,22 @@
 	crypto_tfm_clear_flags(crypto_blkcipher_tfm(tfm), flags);
 }
 
+/**
+ * crypto_blkcipher_setkey() - set key for cipher
+ * @tfm: cipher handle
+ * @key: buffer holding the key
+ * @keylen: length of the key in bytes
+ *
+ * The caller provided key is set for the block cipher referenced by the cipher
+ * handle.
+ *
+ * Note, the key length determines the cipher type. Many block ciphers implement
+ * different cipher modes depending on the key size, such as AES-128 vs AES-192
+ * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
+ * is performed.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 static inline int crypto_blkcipher_setkey(struct crypto_blkcipher *tfm,
 					  const u8 *key, unsigned int keylen)
 {
@@ -990,6 +1270,24 @@
 						 key, keylen);
 }
 
+/**
+ * crypto_blkcipher_encrypt() - encrypt plaintext
+ * @desc: reference to the block cipher handle with meta data
+ * @dst: scatter/gather list that is filled by the cipher operation with the
+ *	ciphertext
+ * @src: scatter/gather list that holds the plaintext
+ * @nbytes: number of bytes of the plaintext to encrypt.
+ *
+ * Encrypt plaintext data using the IV set by the caller with a preceding
+ * call of crypto_blkcipher_set_iv.
+ *
+ * The blkcipher_desc data structure must be filled by the caller and can
+ * reside on the stack. The caller must fill desc as follows: desc.tfm is filled
+ * with the block cipher handle; desc.flags is filled with either
+ * CRYPTO_TFM_REQ_MAY_SLEEP or 0.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_blkcipher_encrypt(struct blkcipher_desc *desc,
 					   struct scatterlist *dst,
 					   struct scatterlist *src,
@@ -999,6 +1297,25 @@
 	return crypto_blkcipher_crt(desc->tfm)->encrypt(desc, dst, src, nbytes);
 }
 
+/**
+ * crypto_blkcipher_encrypt_iv() - encrypt plaintext with dedicated IV
+ * @desc: reference to the block cipher handle with meta data
+ * @dst: scatter/gather list that is filled by the cipher operation with the
+ *	ciphertext
+ * @src: scatter/gather list that holds the plaintext
+ * @nbytes: number of bytes of the plaintext to encrypt.
+ *
+ * Encrypt plaintext data with the use of an IV that is solely used for this
+ * cipher operation. Any previously set IV is not used.
+ *
+ * The blkcipher_desc data structure must be filled by the caller and can
+ * reside on the stack. The caller must fill desc as follows: desc.tfm is filled
+ * with the block cipher handle; desc.info is filled with the IV to be used for
+ * the current operation; desc.flags is filled with either
+ * CRYPTO_TFM_REQ_MAY_SLEEP or 0.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_blkcipher_encrypt_iv(struct blkcipher_desc *desc,
 					      struct scatterlist *dst,
 					      struct scatterlist *src,
@@ -1007,6 +1324,23 @@
 	return crypto_blkcipher_crt(desc->tfm)->encrypt(desc, dst, src, nbytes);
 }
 
+/**
+ * crypto_blkcipher_decrypt() - decrypt ciphertext
+ * @desc: reference to the block cipher handle with meta data
+ * @dst: scatter/gather list that is filled by the cipher operation with the
+ *	plaintext
+ * @src: scatter/gather list that holds the ciphertext
+ * @nbytes: number of bytes of the ciphertext to decrypt.
+ *
+ * Decrypt ciphertext data using the IV set by the caller with a preceding
+ * call of crypto_blkcipher_set_iv.
+ *
+ * The blkcipher_desc data structure must be filled by the caller as documented
+ * for the crypto_blkcipher_encrypt call above.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ *
+ */
 static inline int crypto_blkcipher_decrypt(struct blkcipher_desc *desc,
 					   struct scatterlist *dst,
 					   struct scatterlist *src,
@@ -1016,6 +1350,22 @@
 	return crypto_blkcipher_crt(desc->tfm)->decrypt(desc, dst, src, nbytes);
 }
 
+/**
+ * crypto_blkcipher_decrypt_iv() - decrypt ciphertext with dedicated IV
+ * @desc: reference to the block cipher handle with meta data
+ * @dst: scatter/gather list that is filled by the cipher operation with the
+ *	plaintext
+ * @src: scatter/gather list that holds the ciphertext
+ * @nbytes: number of bytes of the ciphertext to decrypt.
+ *
+ * Decrypt ciphertext data with the use of an IV that is solely used for this
+ * cipher operation. Any previously set IV is not used.
+ *
+ * The blkcipher_desc data structure must be filled by the caller as documented
+ * for the crypto_blkcipher_encrypt_iv call above.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_blkcipher_decrypt_iv(struct blkcipher_desc *desc,
 					      struct scatterlist *dst,
 					      struct scatterlist *src,
@@ -1024,18 +1374,54 @@
 	return crypto_blkcipher_crt(desc->tfm)->decrypt(desc, dst, src, nbytes);
 }
 
+/**
+ * crypto_blkcipher_set_iv() - set IV for cipher
+ * @tfm: cipher handle
+ * @src: buffer holding the IV
+ * @len: length of the IV in bytes
+ *
+ * The caller provided IV is set for the block cipher referenced by the cipher
+ * handle.
+ */
 static inline void crypto_blkcipher_set_iv(struct crypto_blkcipher *tfm,
 					   const u8 *src, unsigned int len)
 {
 	memcpy(crypto_blkcipher_crt(tfm)->iv, src, len);
 }
 
+/**
+ * crypto_blkcipher_get_iv() - obtain IV from cipher
+ * @tfm: cipher handle
+ * @dst: buffer filled with the IV
+ * @len: length of the buffer dst
+ *
+ * The caller can obtain the IV set for the block cipher referenced by the
+ * cipher handle and store it into the user-provided buffer. If the buffer
+ * has an insufficient space, the IV is truncated to fit the buffer.
+ */
 static inline void crypto_blkcipher_get_iv(struct crypto_blkcipher *tfm,
 					   u8 *dst, unsigned int len)
 {
 	memcpy(dst, crypto_blkcipher_crt(tfm)->iv, len);
 }
 
+/**
+ * DOC: Single Block Cipher API
+ *
+ * The single block cipher API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_CIPHER (listed as type "cipher" in /proc/crypto).
+ *
+ * Using the single block cipher API calls, operations with the basic cipher
+ * primitive can be implemented. These cipher primitives exclude any block
+ * chaining operations including IV handling.
+ *
+ * The purpose of this single block cipher API is to support the implementation
+ * of templates or other concepts that only need to perform the cipher operation
+ * on one block at a time. Templates invoke the underlying cipher primitive
+ * block-wise and process either the input or the output data of these cipher
+ * operations.
+ */
+
 static inline struct crypto_cipher *__crypto_cipher_cast(struct crypto_tfm *tfm)
 {
 	return (struct crypto_cipher *)tfm;
@@ -1047,6 +1433,20 @@
 	return __crypto_cipher_cast(tfm);
 }
 
+/**
+ * crypto_alloc_cipher() - allocate single block cipher handle
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	     single block cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Allocate a cipher handle for a single block cipher. The returned struct
+ * crypto_cipher is the cipher handle that is required for any subsequent API
+ * invocation for that single block cipher.
+ *
+ * Return: allocated cipher handle in case of success; IS_ERR() is true in case
+ *	   of an error, PTR_ERR() returns the error code.
+ */
 static inline struct crypto_cipher *crypto_alloc_cipher(const char *alg_name,
 							u32 type, u32 mask)
 {
@@ -1062,11 +1462,25 @@
 	return &tfm->base;
 }
 
+/**
+ * crypto_free_cipher() - zeroize and free the single block cipher handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_cipher(struct crypto_cipher *tfm)
 {
 	crypto_free_tfm(crypto_cipher_tfm(tfm));
 }
 
+/**
+ * crypto_has_cipher() - Search for the availability of a single block cipher
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *	     single block cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Return: true when the single block cipher is known to the kernel crypto API;
+ *	   false otherwise
+ */
 static inline int crypto_has_cipher(const char *alg_name, u32 type, u32 mask)
 {
 	type &= ~CRYPTO_ALG_TYPE_MASK;
@@ -1081,6 +1495,16 @@
 	return &crypto_cipher_tfm(tfm)->crt_cipher;
 }
 
+/**
+ * crypto_cipher_blocksize() - obtain block size for cipher
+ * @tfm: cipher handle
+ *
+ * The block size for the single block cipher referenced with the cipher handle
+ * tfm is returned. The caller may use that information to allocate appropriate
+ * memory for the data returned by the encryption or decryption operation
+ *
+ * Return: block size of cipher
+ */
 static inline unsigned int crypto_cipher_blocksize(struct crypto_cipher *tfm)
 {
 	return crypto_tfm_alg_blocksize(crypto_cipher_tfm(tfm));
@@ -1108,6 +1532,22 @@
 	crypto_tfm_clear_flags(crypto_cipher_tfm(tfm), flags);
 }
 
+/**
+ * crypto_cipher_setkey() - set key for cipher
+ * @tfm: cipher handle
+ * @key: buffer holding the key
+ * @keylen: length of the key in bytes
+ *
+ * The caller provided key is set for the single block cipher referenced by the
+ * cipher handle.
+ *
+ * Note, the key length determines the cipher type. Many block ciphers implement
+ * different cipher modes depending on the key size, such as AES-128 vs AES-192
+ * vs. AES-256. When providing a 16 byte key for an AES cipher handle, AES-128
+ * is performed.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 static inline int crypto_cipher_setkey(struct crypto_cipher *tfm,
                                        const u8 *key, unsigned int keylen)
 {
@@ -1115,6 +1555,15 @@
 						  key, keylen);
 }
 
+/**
+ * crypto_cipher_encrypt_one() - encrypt one block of plaintext
+ * @tfm: cipher handle
+ * @dst: points to the buffer that will be filled with the ciphertext
+ * @src: buffer holding the plaintext to be encrypted
+ *
+ * Invoke the encryption operation of one block. The caller must ensure that
+ * the plaintext and ciphertext buffers are at least one block in size.
+ */
 static inline void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
 					     u8 *dst, const u8 *src)
 {
@@ -1122,6 +1571,15 @@
 						dst, src);
 }
 
+/**
+ * crypto_cipher_decrypt_one() - decrypt one block of ciphertext
+ * @tfm: cipher handle
+ * @dst: points to the buffer that will be filled with the plaintext
+ * @src: buffer holding the ciphertext to be decrypted
+ *
+ * Invoke the decryption operation of one block. The caller must ensure that
+ * the plaintext and ciphertext buffers are at least one block in size.
+ */
 static inline void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
 					     u8 *dst, const u8 *src)
 {
@@ -1129,6 +1587,13 @@
 						dst, src);
 }
 
+/**
+ * DOC: Synchronous Message Digest API
+ *
+ * The synchronous message digest API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_HASH (listed as type "hash" in /proc/crypto)
+ */
+
 static inline struct crypto_hash *__crypto_hash_cast(struct crypto_tfm *tfm)
 {
 	return (struct crypto_hash *)tfm;
@@ -1141,6 +1606,20 @@
 	return __crypto_hash_cast(tfm);
 }
 
+/**
+ * crypto_alloc_hash() - allocate synchronous 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_hash 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.
+ */
 static inline struct crypto_hash *crypto_alloc_hash(const char *alg_name,
 						    u32 type, u32 mask)
 {
@@ -1157,11 +1636,25 @@
 	return &tfm->base;
 }
 
+/**
+ * crypto_free_hash() - zeroize and free message digest handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_hash(struct crypto_hash *tfm)
 {
 	crypto_free_tfm(crypto_hash_tfm(tfm));
 }
 
+/**
+ * crypto_has_hash() - Search for the availability of a message digest
+ * @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
+ *
+ * Return: true when the message digest cipher is known to the kernel crypto
+ *	   API; false otherwise
+ */
 static inline int crypto_has_hash(const char *alg_name, u32 type, u32 mask)
 {
 	type &= ~CRYPTO_ALG_TYPE_MASK;
@@ -1177,6 +1670,15 @@
 	return &crypto_hash_tfm(tfm)->crt_hash;
 }
 
+/**
+ * crypto_hash_blocksize() - obtain block size for message digest
+ * @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_hash_blocksize(struct crypto_hash *tfm)
 {
 	return crypto_tfm_alg_blocksize(crypto_hash_tfm(tfm));
@@ -1187,6 +1689,15 @@
 	return crypto_tfm_alg_alignmask(crypto_hash_tfm(tfm));
 }
 
+/**
+ * crypto_hash_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
+ */
 static inline unsigned int crypto_hash_digestsize(struct crypto_hash *tfm)
 {
 	return crypto_hash_crt(tfm)->digestsize;
@@ -1207,11 +1718,38 @@
 	crypto_tfm_clear_flags(crypto_hash_tfm(tfm), flags);
 }
 
+/**
+ * crypto_hash_init() - (re)initialize message digest handle
+ * @desc: cipher request handle that to be filled by caller --
+ *	  desc.tfm is filled with the hash cipher handle;
+ *	  desc.flags is filled with either CRYPTO_TFM_REQ_MAY_SLEEP or 0.
+ *
+ * The call (re-)initializes the message digest referenced by the hash cipher
+ * 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_hash_init(struct hash_desc *desc)
 {
 	return crypto_hash_crt(desc->tfm)->init(desc);
 }
 
+/**
+ * crypto_hash_update() - add data to message digest for processing
+ * @desc: cipher request handle
+ * @sg: scatter / gather list pointing to the data to be added to the message
+ *      digest
+ * @nbytes: number of bytes to be processed from @sg
+ *
+ * Updates the message digest state of the cipher handle pointed to by the
+ * hash cipher request handle with the input data pointed to by the
+ * scatter/gather list.
+ *
+ * Return: 0 if the message digest update was successful; < 0 if an error
+ *	   occurred
+ */
 static inline int crypto_hash_update(struct hash_desc *desc,
 				     struct scatterlist *sg,
 				     unsigned int nbytes)
@@ -1219,11 +1757,39 @@
 	return crypto_hash_crt(desc->tfm)->update(desc, sg, nbytes);
 }
 
+/**
+ * crypto_hash_final() - calculate message digest
+ * @desc: cipher request handle
+ * @out: message digest output buffer -- The caller must ensure that the out
+ *	 buffer has a sufficient size (e.g. by using the crypto_hash_digestsize
+ *	 function).
+ *
+ * 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.
+ *
+ * Return: 0 if the message digest creation was successful; < 0 if an error
+ *	   occurred
+ */
 static inline int crypto_hash_final(struct hash_desc *desc, u8 *out)
 {
 	return crypto_hash_crt(desc->tfm)->final(desc, out);
 }
 
+/**
+ * crypto_hash_digest() - calculate message digest for a buffer
+ * @desc: see crypto_hash_final()
+ * @sg: see crypto_hash_update()
+ * @nbytes:  see crypto_hash_update()
+ * @out: see crypto_hash_final()
+ *
+ * This function is a "short-hand" for the function calls of crypto_hash_init,
+ * crypto_hash_update and crypto_hash_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
+ */
 static inline int crypto_hash_digest(struct hash_desc *desc,
 				     struct scatterlist *sg,
 				     unsigned int nbytes, u8 *out)
@@ -1231,6 +1797,17 @@
 	return crypto_hash_crt(desc->tfm)->digest(desc, sg, nbytes, out);
 }
 
+/**
+ * crypto_hash_setkey() - set key for message digest
+ * @hash: cipher handle
+ * @key: buffer holding the key
+ * @keylen: length of the key in bytes
+ *
+ * The caller provided key is set for the message digest 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
+ */
 static inline int crypto_hash_setkey(struct crypto_hash *hash,
 				     const u8 *key, unsigned int keylen)
 {