Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto update from Herbert Xu:
 - The crypto API is now documented :)
 - Disallow arbitrary module loading through crypto API.
 - Allow get request with empty driver name through crypto_user.
 - Allow speed testing of arbitrary hash functions.
 - Add caam support for ctr(aes), gcm(aes) and their derivatives.
 - nx now supports concurrent hashing properly.
 - Add sahara support for SHA1/256.
 - Add ARM64 version of CRC32.
 - Misc fixes.

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (77 commits)
  crypto: tcrypt - Allow speed testing of arbitrary hash functions
  crypto: af_alg - add user space interface for AEAD
  crypto: qat - fix problem with coalescing enable logic
  crypto: sahara - add support for SHA1/256
  crypto: sahara - replace tasklets with kthread
  crypto: sahara - add support for i.MX53
  crypto: sahara - fix spinlock initialization
  crypto: arm - replace memset by memzero_explicit
  crypto: powerpc - replace memset by memzero_explicit
  crypto: sha - replace memset by memzero_explicit
  crypto: sparc - replace memset by memzero_explicit
  crypto: algif_skcipher - initialize upon init request
  crypto: algif_skcipher - removed unneeded code
  crypto: algif_skcipher - Fixed blocking recvmsg
  crypto: drbg - use memzero_explicit() for clearing sensitive data
  crypto: drbg - use MODULE_ALIAS_CRYPTO
  crypto: include crypto- module prefix in template
  crypto: user - add MODULE_ALIAS
  crypto: sha-mb - remove a bogus NULL check
  crytpo: qat - Fix 64 bytes requests
  ...

6 files changed, 1685 insertions, 3 deletions

diff --git a/include/crypto/hash.h b/include/crypto/hash.h
index 74b13ec1ebd4..98abda9ed3aa 100644
--- a/include/crypto/hash.h
+++ b/include/crypto/hash.h
@@ -17,6 +17,32 @@
 
 struct crypto_ahash;
 
+/**
+ * DOC: Message Digest Algorithm Definitions
+ *
+ * These data structures define modular message digest algorithm
+ * implementations, managed via crypto_register_ahash(),
+ * crypto_register_shash(), crypto_unregister_ahash() and
+ * crypto_unregister_shash().
+ */
+
+/**
+ * struct hash_alg_common - define properties of message digest
+ * @digestsize: Size of the result of the transformation. A buffer of this size
+ *              must be available to the @final and @finup calls, so they can
+ *              store the resulting hash into it. For various predefined sizes,
+ *              search include/crypto/ using
+ *              git grep _DIGEST_SIZE include/crypto.
+ * @statesize: Size of the block for partial state of the transformation. A
+ *             buffer of this size must be passed to the @export function as it
+ *             will save the partial state of the transformation into it. On the
+ *             other side, the @import function will load the state from a
+ *             buffer of this size as well.
+ * @base: Start of data structure of cipher algorithm. The common data
+ *        structure of crypto_alg contains information common to all ciphers.
+ *        The hash_alg_common data structure now adds the hash-specific
+ *        information.
+ */
 struct hash_alg_common {
         unsigned int digestsize;
         unsigned int statesize;
@@ -37,6 +63,63 @@ struct ahash_request {
         void *__ctx[] CRYPTO_MINALIGN_ATTR;
 };
 
+/**
+ * struct ahash_alg - asynchronous message digest definition
+ * @init: Initialize the transformation context. Intended only to initialize the
+ *        state of the HASH transformation at the begining. This shall fill in
+ *        the internal structures used during the entire duration of the whole
+ *        transformation. No data processing happens at this point.
+ * @update: Push a chunk of data into the driver for transformation. This
+ *         function actually pushes blocks of data from upper layers into the
+ *         driver, which then passes those to the hardware as seen fit. This
+ *         function must not finalize the HASH transformation by calculating the
+ *         final message digest as this only adds more data into the
+ *         transformation. This function shall not modify the transformation
+ *         context, as this function may be called in parallel with the same
+ *         transformation object. Data processing can happen synchronously
+ *         [SHASH] or asynchronously [AHASH] at this point.
+ * @final: Retrieve result from the driver. This function finalizes the
+ *         transformation and retrieves the resulting hash from the driver and
+ *         pushes it back to upper layers. No data processing happens at this
+ *         point.
+ * @finup: Combination of @update and @final. This function is effectively a
+ *         combination of @update and @final calls issued in sequence. As some
+ *         hardware cannot do @update and @final separately, this callback was
+ *         added to allow such hardware to be used at least by IPsec. Data
+ *         processing can happen synchronously [SHASH] or asynchronously [AHASH]
+ *         at this point.
+ * @digest: Combination of @init and @update and @final. This function
+ *          effectively behaves as the entire chain of operations, @init,
+ *          @update and @final issued in sequence. Just like @finup, this was
+ *          added for hardware which cannot do even the @finup, but can only do
+ *          the whole transformation in one run. Data processing can happen
+ *          synchronously [SHASH] or asynchronously [AHASH] at this point.
+ * @setkey: Set optional key used by the hashing algorithm. Intended to push
+ *          optional key used by the hashing algorithm from upper layers into
+ *          the driver. This function can store the key in the transformation
+ *          context or can outright program it into the hardware. In the former
+ *          case, one must be careful to program the key into the hardware at
+ *          appropriate time and one must be careful that .setkey() can be
+ *          called multiple times during the existence of the transformation
+ *          object. Not  all hashing algorithms do implement this function as it
+ *          is only needed for keyed message digests. SHAx/MDx/CRCx do NOT
+ *          implement this function. HMAC(MDx)/HMAC(SHAx)/CMAC(AES) do implement
+ *          this function. This function must be called before any other of the
+ *          @init, @update, @final, @finup, @digest is called. No data
+ *          processing happens at this point.
+ * @export: Export partial state of the transformation. This function dumps the
+ *          entire state of the ongoing transformation into a provided block of
+ *          data so it can be @import 'ed back later on. This is useful in case
+ *          you want to save partial result of the transformation after
+ *          processing certain amount of data and reload this partial result
+ *          multiple times later on for multiple re-use. No data processing
+ *          happens at this point.
+ * @import: Import partial state of the transformation. This function loads the
+ *          entire state of the ongoing transformation from a provided block of
+ *          data so the transformation can continue from this point onward. No
+ *          data processing happens at this point.
+ * @halg: see struct hash_alg_common
+ */
 struct ahash_alg {
         int (*init)(struct ahash_request *req);
         int (*update)(struct ahash_request *req);
@@ -63,6 +146,23 @@ struct shash_desc {
                 crypto_shash_descsize(ctx)] CRYPTO_MINALIGN_ATTR; \
         struct shash_desc *shash = (struct shash_desc *)__##shash##_desc
 
+/**
+ * struct shash_alg - synchronous message digest definition
+ * @init: see struct ahash_alg
+ * @update: see struct ahash_alg
+ * @final: see struct ahash_alg
+ * @finup: see struct ahash_alg
+ * @digest: see struct ahash_alg
+ * @export: see struct ahash_alg
+ * @import: see struct ahash_alg
+ * @setkey: see struct ahash_alg
+ * @digestsize: see struct ahash_alg
+ * @statesize: see struct ahash_alg
+ * @descsize: Size of the operational state for the message digest. This state
+ *            size is the memory size that needs to be allocated for
+ *            shash_desc.__ctx
+ * @base: internally used
+ */
 struct shash_alg {
         int (*init)(struct shash_desc *desc);
         int (*update)(struct shash_desc *desc, const u8 *data,
@@ -107,11 +207,35 @@ 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);
 
@@ -120,6 +244,10 @@ 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));
@@ -143,6 +271,16 @@ 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;
@@ -168,12 +306,32 @@ 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;
@@ -184,38 +342,166 @@ 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)
 {
@@ -230,6 +516,10 @@ 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);
@@ -241,6 +531,31 @@ 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,
@@ -251,6 +566,19 @@ 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)
@@ -260,6 +588,33 @@ static inline void ahash_request_set_crypt(struct ahash_request *req,
         req->result = result;
 }
 
+/**
+ * DOC: Synchronous Message Digest API
+ *
+ * The synchronous message digest API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_SHASH (listed as type "shash" in /proc/crypto)
+ *
+ * The message digest API is able to maintain state information for the
+ * caller.
+ *
+ * The synchronous message digest API can store user-related context in in its
+ * shash_desc request data structure.
+ */
+
+/**
+ * crypto_alloc_shash() - allocate 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_shash 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.
+ */
 struct crypto_shash *crypto_alloc_shash(const char *alg_name, u32 type,
                                         u32 mask);
 
@@ -268,6 +623,10 @@ static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm)
         return &tfm->base;
 }
 
+/**
+ * crypto_free_shash() - zeroize and free the message digest handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_shash(struct crypto_shash *tfm)
 {
         crypto_destroy_tfm(tfm, crypto_shash_tfm(tfm));
@@ -279,6 +638,15 @@ static inline unsigned int crypto_shash_alignmask(
         return crypto_tfm_alg_alignmask(crypto_shash_tfm(tfm));
 }
 
+/**
+ * crypto_shash_blocksize() - obtain block size for cipher
+ * @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_shash_blocksize(struct crypto_shash *tfm)
 {
         return crypto_tfm_alg_blocksize(crypto_shash_tfm(tfm));
@@ -294,6 +662,15 @@ static inline struct shash_alg *crypto_shash_alg(struct crypto_shash *tfm)
         return __crypto_shash_alg(crypto_shash_tfm(tfm)->__crt_alg);
 }
 
+/**
+ * crypto_shash_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: digest size of cipher
+ */
 static inline unsigned int crypto_shash_digestsize(struct crypto_shash *tfm)
 {
         return crypto_shash_alg(tfm)->digestsize;
@@ -319,6 +696,21 @@ static inline void crypto_shash_clear_flags(struct crypto_shash *tfm, u32 flags)
         crypto_tfm_clear_flags(crypto_shash_tfm(tfm), flags);
 }
 
+/**
+ * crypto_shash_descsize() - obtain the operational state size
+ * @tfm: cipher handle
+ *
+ * The size of the operational state the cipher needs during operation is
+ * returned for the hash referenced with the cipher handle. This size is
+ * required to calculate the memory requirements to allow the caller allocating
+ * sufficient memory for operational state.
+ *
+ * The operational state is defined with struct shash_desc where the size of
+ * that data structure is to be calculated as
+ * sizeof(struct shash_desc) + crypto_shash_descsize(alg)
+ *
+ * Return: size of the operational state
+ */
 static inline unsigned int crypto_shash_descsize(struct crypto_shash *tfm)
 {
         return tfm->descsize;
@@ -329,29 +721,129 @@ static inline void *shash_desc_ctx(struct shash_desc *desc)
         return desc->__ctx;
 }
 
+/**
+ * crypto_shash_setkey() - set key for message digest
+ * @tfm: cipher handle
+ * @key: buffer holding the key
+ * @keylen: length of the key in bytes
+ *
+ * The caller provided key is set for the keyed message digest cipher. The
+ * cipher handle must point to a keyed message digest cipher in order for this
+ * function to succeed.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 int crypto_shash_setkey(struct crypto_shash *tfm, const u8 *key,
                         unsigned int keylen);
+
+/**
+ * crypto_shash_digest() - calculate message digest for buffer
+ * @desc: see crypto_shash_final()
+ * @data: see crypto_shash_update()
+ * @len: see crypto_shash_update()
+ * @out: see crypto_shash_final()
+ *
+ * This function is a "short-hand" for the function calls of crypto_shash_init,
+ * crypto_shash_update and crypto_shash_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_shash_digest(struct shash_desc *desc, const u8 *data,
                         unsigned int len, u8 *out);
 
+/**
+ * crypto_shash_export() - extract operational state for message digest
+ * @desc: reference to the operational state 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 operational state handle into the
+ * caller-allocated output buffer out which must have sufficient size (e.g. by
+ * calling crypto_shash_descsize).
+ *
+ * Return: 0 if the export creation was successful; < 0 if an error occurred
+ */
 static inline int crypto_shash_export(struct shash_desc *desc, void *out)
 {
         return crypto_shash_alg(desc->tfm)->export(desc, out);
 }
 
+/**
+ * crypto_shash_import() - import operational state
+ * @desc: reference to the operational state handle the state imported into
+ * @in: buffer holding the state
+ *
+ * This function imports the hash state into the operational state 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_shash_import(struct shash_desc *desc, const void *in)
 {
         return crypto_shash_alg(desc->tfm)->import(desc, in);
 }
 
+/**
+ * crypto_shash_init() - (re)initialize message digest
+ * @desc: operational state handle that is already filled
+ *
+ * The call (re-)initializes the message digest referenced by the
+ * operational state 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_shash_init(struct shash_desc *desc)
 {
         return crypto_shash_alg(desc->tfm)->init(desc);
 }
 
+/**
+ * crypto_shash_update() - add data to message digest for processing
+ * @desc: operational state handle that is already initialized
+ * @data: input data to be added to the message digest
+ * @len: length of the input data
+ *
+ * Updates the message digest state of the operational state handle.
+ *
+ * Return: 0 if the message digest update was successful; < 0 if an error
+ *         occurred
+ */
 int crypto_shash_update(struct shash_desc *desc, const u8 *data,
                         unsigned int len);
+
+/**
+ * crypto_shash_final() - calculate message digest
+ * @desc: operational state handle that is already filled with data
+ * @out: output buffer filled with the message digest
+ *
+ * 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. The caller must ensure that the output buffer is
+ * large enough by using crypto_shash_digestsize.
+ *
+ * Return: 0 if the message digest creation was successful; < 0 if an error
+ *         occurred
+ */
 int crypto_shash_final(struct shash_desc *desc, u8 *out);
+
+/**
+ * crypto_shash_finup() - calculate message digest of buffer
+ * @desc: see crypto_shash_final()
+ * @data: see crypto_shash_update()
+ * @len: see crypto_shash_update()
+ * @out: see crypto_shash_final()
+ *
+ * This function is a "short-hand" for the function calls of
+ * crypto_shash_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_shash_finup(struct shash_desc *desc, const u8 *data,
                        unsigned int len, u8 *out);
 
diff --git a/include/crypto/if_alg.h b/include/crypto/if_alg.h
index d61c11170213..cd62bf4289e9 100644
--- a/include/crypto/if_alg.h
+++ b/include/crypto/if_alg.h
@@ -42,6 +42,7 @@ struct af_alg_completion {
 struct af_alg_control {
         struct af_alg_iv *iv;
         int op;
+        unsigned int aead_assoclen;
 };
 
 struct af_alg_type {
diff --git a/include/crypto/rng.h b/include/crypto/rng.h
index c93f9b917925..a16fb10142bf 100644
--- a/include/crypto/rng.h
+++ b/include/crypto/rng.h
@@ -20,11 +20,38 @@ extern struct crypto_rng *crypto_default_rng;
 int crypto_get_default_rng(void);
 void crypto_put_default_rng(void);
 
+/**
+ * DOC: Random number generator API
+ *
+ * The random number generator API is used with the ciphers of type
+ * CRYPTO_ALG_TYPE_RNG (listed as type "rng" in /proc/crypto)
+ */
+
 static inline struct crypto_rng *__crypto_rng_cast(struct crypto_tfm *tfm)
 {
         return (struct crypto_rng *)tfm;
 }
 
+/**
+ * crypto_alloc_rng() -- allocate RNG 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 random number generator. The returned struct
+ * crypto_rng is the cipher handle that is required for any subsequent
+ * API invocation for that random number generator.
+ *
+ * For all random number generators, this call creates a new private copy of
+ * the random number generator that does not share a state with other
+ * instances. The only exception is the "krng" random number generator which
+ * is a kernel crypto API use case for the get_random_bytes() function of the
+ * /dev/random driver.
+ *
+ * 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_rng *crypto_alloc_rng(const char *alg_name,
                                                   u32 type, u32 mask)
 {
@@ -40,6 +67,14 @@ static inline struct crypto_tfm *crypto_rng_tfm(struct crypto_rng *tfm)
         return &tfm->base;
 }
 
+/**
+ * crypto_rng_alg - obtain name of RNG
+ * @tfm: cipher handle
+ *
+ * Return the generic name (cra_name) of the initialized random number generator
+ *
+ * Return: generic name string
+ */
 static inline struct rng_alg *crypto_rng_alg(struct crypto_rng *tfm)
 {
         return &crypto_rng_tfm(tfm)->__crt_alg->cra_rng;
@@ -50,23 +85,68 @@ static inline struct rng_tfm *crypto_rng_crt(struct crypto_rng *tfm)
         return &crypto_rng_tfm(tfm)->crt_rng;
 }
 
+/**
+ * crypto_free_rng() - zeroize and free RNG handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_rng(struct crypto_rng *tfm)
 {
         crypto_free_tfm(crypto_rng_tfm(tfm));
 }
 
+/**
+ * crypto_rng_get_bytes() - get random number
+ * @tfm: cipher handle
+ * @rdata: output buffer holding the random numbers
+ * @dlen: length of the output buffer
+ *
+ * This function fills the caller-allocated buffer with random numbers using the
+ * random number generator referenced by the cipher handle.
+ *
+ * Return: > 0 function was successful and returns the number of generated
+ *         bytes; < 0 if an error occurred
+ */
 static inline int crypto_rng_get_bytes(struct crypto_rng *tfm,
                                        u8 *rdata, unsigned int dlen)
 {
         return crypto_rng_crt(tfm)->rng_gen_random(tfm, rdata, dlen);
 }
 
+/**
+ * crypto_rng_reset() - re-initialize the RNG
+ * @tfm: cipher handle
+ * @seed: seed input data
+ * @slen: length of the seed input data
+ *
+ * The reset function completely re-initializes the random number generator
+ * referenced by the cipher handle by clearing the current state. The new state
+ * is initialized with the caller provided seed or automatically, depending
+ * on the random number generator type (the ANSI X9.31 RNG requires
+ * caller-provided seed, the SP800-90A DRBGs perform an automatic seeding).
+ * The seed is provided as a parameter to this function call. The provided seed
+ * should have the length of the seed size defined for the random number
+ * generator as defined by crypto_rng_seedsize.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 static inline int crypto_rng_reset(struct crypto_rng *tfm,
                                    u8 *seed, unsigned int slen)
 {
         return crypto_rng_crt(tfm)->rng_reset(tfm, seed, slen);
 }
 
+/**
+ * crypto_rng_seedsize() - obtain seed size of RNG
+ * @tfm: cipher handle
+ *
+ * The function returns the seed size for the random number generator
+ * referenced by the cipher handle. This value may be zero if the random
+ * number generator does not implement or require a reseeding. For example,
+ * the SP800-90A DRBGs implement an automated reseeding after reaching a
+ * pre-defined threshold.
+ *
+ * Return: seed size for the random number generator
+ */
 static inline int crypto_rng_seedsize(struct crypto_rng *tfm)
 {
         return crypto_rng_alg(tfm)->seedsize;
diff --git a/include/linux/crypto.h b/include/linux/crypto.h
index d45e949699ea..9c8776d0ada8 100644
--- a/include/linux/crypto.h
+++ b/include/linux/crypto.h
@@ -26,6 +26,19 @@
 #include <linux/uaccess.h>
 
 /*
+ * Autoloaded crypto modules should only use a prefixed name to avoid allowing
+ * arbitrary modules to be loaded. Loading from userspace may still need the
+ * unprefixed names, so retains those aliases as well.
+ * This uses __MODULE_INFO directly instead of MODULE_ALIAS because pre-4.3
+ * gcc (e.g. avr32 toolchain) uses __LINE__ for uniqueness, and this macro
+ * expands twice on the same line. Instead, use a separate base name for the
+ * alias.
+ */
+#define MODULE_ALIAS_CRYPTO(name)       \
+                __MODULE_INFO(alias, alias_userspace, name);    \
+                __MODULE_INFO(alias, alias_crypto, "crypto-" name)
+
+/*
  * Algorithm masks and types.
  */
 #define CRYPTO_ALG_TYPE_MASK            0x0000000f
@@ -127,6 +140,13 @@ 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;
@@ -194,9 +214,63 @@ struct hash_desc {
         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,
@@ -213,6 +287,32 @@ struct ablkcipher_alg {
         unsigned int ivsize;
 };
 
+/**
+ * struct aead_alg - AEAD cipher definition
+ * @maxauthsize: Set the maximum authentication tag size supported by the
+ *               transformation. A transformation may support smaller tag sizes.
+ *               As the authentication tag is a message digest to ensure the
+ *               integrity of the encrypted data, a consumer typically wants the
+ *               largest authentication tag possible as defined by this
+ *               variable.
+ * @setauthsize: Set authentication size for the AEAD transformation. This
+ *               function is used to specify the consumer requested size of the
+ *               authentication tag to be either generated by the transformation
+ *               during encryption or the size of the authentication tag to be
+ *               supplied during the decryption operation. This function is also
+ *               responsible for checking the authentication tag size for
+ *               validity.
+ * @setkey: see struct ablkcipher_alg
+ * @encrypt: see struct ablkcipher_alg
+ * @decrypt: see struct ablkcipher_alg
+ * @givencrypt: see struct ablkcipher_alg
+ * @givdecrypt: see struct ablkcipher_alg
+ * @geniv: see struct ablkcipher_alg
+ * @ivsize: see struct ablkcipher_alg
+ *
+ * All fields except @givencrypt , @givdecrypt , @geniv and @ivsize are
+ * mandatory and must be filled.
+ */
 struct aead_alg {
         int (*setkey)(struct crypto_aead *tfm, const u8 *key,
                       unsigned int keylen);
@@ -228,6 +328,18 @@ struct aead_alg {
         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);
@@ -245,6 +357,53 @@ struct blkcipher_alg {
         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;
@@ -261,6 +420,25 @@ struct compress_alg {
                               unsigned int slen, u8 *dst, unsigned int *dlen);
 };
 
+/**
+ * struct rng_alg - random number generator definition
+ * @rng_make_random: The function defined by this variable obtains a random
+ *                   number. The random number generator transform must generate
+ *                   the random number out of the context provided with this
+ *                   call.
+ * @rng_reset: Reset of the random number generator by clearing the entire state.
+ *             With the invocation of this function call, the random number
+ *             generator shall completely reinitialize its state. If the random
+ *             number generator requires a seed for setting up a new state,
+ *             the seed must be provided by the consumer while invoking this
+ *             function. The required size of the seed is defined with
+ *             @seedsize .
+ * @seedsize: The seed size required for a random number generator
+ *            initialization defined with this variable. Some random number
+ *            generators like the SP800-90A DRBG does not require a seed as the
+ *            seeding is implemented internally without the need of support by
+ *            the consumer. In this case, the seed size is set to zero.
+ */
 struct rng_alg {
         int (*rng_make_random)(struct crypto_rng *tfm, u8 *rdata,
                                unsigned int dlen);
@@ -277,6 +455,81 @@ struct rng_alg {
 #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
+ *            trasnformation types. There are multiple options:
+ *            &crypto_blkcipher_type, &crypto_ablkcipher_type,
+ *            &crypto_ahash_type, &crypto_aead_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;
@@ -581,6 +834,50 @@ static inline u32 crypto_skcipher_mask(u32 mask)
         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);
 
@@ -590,11 +887,25 @@ static inline struct crypto_tfm *crypto_ablkcipher_tfm(
         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)
 {
@@ -608,12 +919,31 @@ static inline struct ablkcipher_tfm *crypto_ablkcipher_crt(
         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)
 {
@@ -643,6 +973,22 @@ static inline void crypto_ablkcipher_clear_flags(struct crypto_ablkcipher *tfm,
         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)
 {
@@ -651,12 +997,32 @@ static inline int crypto_ablkcipher_setkey(struct crypto_ablkcipher *tfm,
         return crt->setkey(crt->base, key, keylen);
 }
 
+/**
+ * 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 =
@@ -664,6 +1030,17 @@ static inline int crypto_ablkcipher_encrypt(struct ablkcipher_request *req)
         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 =
@@ -671,12 +1048,37 @@ static inline int crypto_ablkcipher_decrypt(struct ablkcipher_request *req)
         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)
 {
@@ -689,6 +1091,18 @@ static inline struct ablkcipher_request *ablkcipher_request_cast(
         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)
 {
@@ -703,11 +1117,40 @@ static inline struct ablkcipher_request *ablkcipher_request_alloc(
         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 compl, void *data)
@@ -717,6 +1160,22 @@ static inline void ablkcipher_request_set_callback(
         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,
@@ -728,11 +1187,55 @@ static inline void ablkcipher_request_set_crypt(
         req->info = iv;
 }
 
+/**
+ * DOC: Authenticated Encryption With Associated Data (AEAD) Cipher API
+ *
+ * The AEAD cipher API is used with the ciphers of type CRYPTO_ALG_TYPE_AEAD
+ * (listed as type "aead" in /proc/crypto)
+ *
+ * The most prominent examples for this type of encryption is GCM and CCM.
+ * However, the kernel supports other types of AEAD ciphers which are defined
+ * with the following cipher string:
+ *
+ *      authenc(keyed message digest, block cipher)
+ *
+ * For example: authenc(hmac(sha256), cbc(aes))
+ *
+ * The example code provided for the asynchronous block cipher operation
+ * applies here as well. Naturally all *ablkcipher* symbols must be exchanged
+ * the *aead* pendants discussed in the following. In addtion, for the AEAD
+ * operation, the aead_request_set_assoc function must be used to set the
+ * pointer to the associated data memory location before performing the
+ * encryption or decryption operation. In case of an encryption, the associated
+ * data memory is filled during the encryption operation. For decryption, the
+ * associated data memory must contain data that is used to verify the integrity
+ * of the decrypted data. Another deviation from the asynchronous block cipher
+ * operation is that the caller should explicitly check for -EBADMSG of the
+ * crypto_aead_decrypt. That error indicates an authentication error, i.e.
+ * a breach in the integrity of the message. In essence, that -EBADMSG error
+ * code is the key bonus an AEAD cipher has over "standard" block chaining
+ * modes.
+ */
+
 static inline struct crypto_aead *__crypto_aead_cast(struct crypto_tfm *tfm)
 {
         return (struct crypto_aead *)tfm;
 }
 
+/**
+ * crypto_alloc_aead() - allocate AEAD cipher handle
+ * @alg_name: is the cra_name / name or cra_driver_name / driver name of the
+ *           AEAD cipher
+ * @type: specifies the type of the cipher
+ * @mask: specifies the mask for the cipher
+ *
+ * Allocate a cipher handle for an AEAD. The returned struct
+ * crypto_aead is the cipher handle that is required for any subsequent
+ * API invocation for that AEAD.
+ *
+ * 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_aead *crypto_alloc_aead(const char *alg_name, u32 type, u32 mask);
 
 static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm)
@@ -740,6 +1243,10 @@ static inline struct crypto_tfm *crypto_aead_tfm(struct crypto_aead *tfm)
         return &tfm->base;
 }
 
+/**
+ * crypto_free_aead() - zeroize and free aead handle
+ * @tfm: cipher handle to be freed
+ */
 static inline void crypto_free_aead(struct crypto_aead *tfm)
 {
         crypto_free_tfm(crypto_aead_tfm(tfm));
@@ -750,16 +1257,47 @@ static inline struct aead_tfm *crypto_aead_crt(struct crypto_aead *tfm)
         return &crypto_aead_tfm(tfm)->crt_aead;
 }
 
+/**
+ * crypto_aead_ivsize() - obtain IV size
+ * @tfm: cipher handle
+ *
+ * The size of the IV for the aead 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_aead_ivsize(struct crypto_aead *tfm)
 {
         return crypto_aead_crt(tfm)->ivsize;
 }
 
+/**
+ * crypto_aead_authsize() - obtain maximum authentication data size
+ * @tfm: cipher handle
+ *
+ * The maximum size of the authentication data for the AEAD cipher referenced
+ * by the AEAD cipher handle is returned. The authentication data size may be
+ * zero if the cipher implements a hard-coded maximum.
+ *
+ * The authentication data may also be known as "tag value".
+ *
+ * Return: authentication data size / tag size in bytes
+ */
 static inline unsigned int crypto_aead_authsize(struct crypto_aead *tfm)
 {
         return crypto_aead_crt(tfm)->authsize;
 }
 
+/**
+ * crypto_aead_blocksize() - obtain block size of cipher
+ * @tfm: cipher handle
+ *
+ * The block size for the AEAD 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_aead_blocksize(struct crypto_aead *tfm)
 {
         return crypto_tfm_alg_blocksize(crypto_aead_tfm(tfm));
@@ -785,6 +1323,22 @@ static inline void crypto_aead_clear_flags(struct crypto_aead *tfm, u32 flags)
         crypto_tfm_clear_flags(crypto_aead_tfm(tfm), flags);
 }
 
+/**
+ * crypto_aead_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 AEAD 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_aead_setkey(struct crypto_aead *tfm, const u8 *key,
                                      unsigned int keylen)
 {
@@ -793,6 +1347,16 @@ static inline int crypto_aead_setkey(struct crypto_aead *tfm, const u8 *key,
         return crt->setkey(crt->base, key, keylen);
 }
 
+/**
+ * crypto_aead_setauthsize() - set authentication data size
+ * @tfm: cipher handle
+ * @authsize: size of the authentication data / tag in bytes
+ *
+ * Set the authentication data size / tag size. AEAD requires an authentication
+ * tag (or MAC) in addition to the associated data.
+ *
+ * Return: 0 if the setting of the key was successful; < 0 if an error occurred
+ */
 int crypto_aead_setauthsize(struct crypto_aead *tfm, unsigned int authsize);
 
 static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req)
@@ -800,27 +1364,105 @@ static inline struct crypto_aead *crypto_aead_reqtfm(struct aead_request *req)
         return __crypto_aead_cast(req->base.tfm);
 }
 
+/**
+ * crypto_aead_encrypt() - encrypt plaintext
+ * @req: reference to the aead_request handle that holds all information
+ *       needed to perform the cipher operation
+ *
+ * Encrypt plaintext data using the aead_request handle. That data structure
+ * and how it is filled with data is discussed with the aead_request_*
+ * functions.
+ *
+ * IMPORTANT NOTE The encryption operation creates the authentication data /
+ *                tag. That data is concatenated with the created ciphertext.
+ *                The ciphertext memory size is therefore the given number of
+ *                block cipher blocks + the size defined by the
+ *                crypto_aead_setauthsize invocation. The caller must ensure
+ *                that sufficient memory is available for the ciphertext and
+ *                the authentication tag.
+ *
+ * Return: 0 if the cipher operation was successful; < 0 if an error occurred
+ */
 static inline int crypto_aead_encrypt(struct aead_request *req)
 {
         return crypto_aead_crt(crypto_aead_reqtfm(req))->encrypt(req);
 }
 
+/**
+ * crypto_aead_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 aead_request handle. That data structure
+ * and how it is filled with data is discussed with the aead_request_*
+ * functions.
+ *
+ * IMPORTANT NOTE The caller must concatenate the ciphertext followed by the
+ *                authentication data / tag. That authentication data / tag
+ *                must have the size defined by the crypto_aead_setauthsize
+ *                invocation.
+ *
+ *
+ * Return: 0 if the cipher operation was successful; -EBADMSG: The AEAD
+ *         cipher operation performs the authentication of the data during the
+ *         decryption operation. Therefore, the function returns this error if
+ *         the authentication of the ciphertext was unsuccessful (i.e. the
+ *         integrity of the ciphertext or the associated data was violated);
+ *         < 0 if an error occurred.
+ */
 static inline int crypto_aead_decrypt(struct aead_request *req)
 {
         return crypto_aead_crt(crypto_aead_reqtfm(req))->decrypt(req);
 }
 
+/**
+ * DOC: Asynchronous AEAD Request Handle
+ *
+ * The aead_request data structure contains all pointers to data required for
+ * the AEAD cipher operation. This includes the cipher handle (which can be
+ * used by multiple aead_request instances), pointer to plaintext and
+ * ciphertext, asynchronous callback function, etc. It acts as a handle to the
+ * aead_request_* API calls in a similar way as AEAD handle to the
+ * crypto_aead_* API calls.
+ */
+
+/**
+ * crypto_aead_reqsize() - obtain size of the request data structure
+ * @tfm: cipher handle
+ *
+ * Return: number of bytes
+ */
 static inline unsigned int crypto_aead_reqsize(struct crypto_aead *tfm)
 {
         return crypto_aead_crt(tfm)->reqsize;
 }
 
+/**
+ * aead_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 aead handle in the request
+ * data structure with a different one.
+ */
 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);
 }
 
+/**
+ * aead_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 AEAD
+ * encrypt and decrypt API calls. During the allocation, the provided aead
+ * 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 aead_request *aead_request_alloc(struct crypto_aead *tfm,
                                                       gfp_t gfp)
 {
@@ -834,11 +1476,40 @@ static inline struct aead_request *aead_request_alloc(struct crypto_aead *tfm,
         return req;
 }
 
+/**
+ * aead_request_free() - zeroize and free request data structure
+ * @req: request data structure cipher handle to be freed
+ */
 static inline void aead_request_free(struct aead_request *req)
 {
         kzfree(req);
 }
 
+/**
+ * aead_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.
+ *
+ * Setting the callback function that is triggered once the cipher operation
+ * completes
+ *
+ * The callback function is registered with the aead_request handle and
+ * must comply with the following template:
+ *
+ *      void callback_function(struct crypto_async_request *req, int error)
+ */
 static inline void aead_request_set_callback(struct aead_request *req,
                                              u32 flags,
                                              crypto_completion_t compl,
@@ -849,6 +1520,36 @@ static inline void aead_request_set_callback(struct aead_request *req,
         req->base.flags = flags;
 }
 
+/**
+ * aead_request_set_crypt - set data buffers
+ * @req: request handle
+ * @src: source scatter / gather list
+ * @dst: destination scatter / gather list
+ * @cryptlen: number of bytes to process from @src
+ * @iv: IV for the cipher operation which must comply with the IV size defined
+ *      by crypto_aead_ivsize()
+ *
+ * Setting 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.
+ *
+ * IMPORTANT NOTE AEAD requires an authentication tag (MAC). For decryption,
+ *                the caller must concatenate the ciphertext followed by the
+ *                authentication tag and provide the entire data stream to the
+ *                decryption operation (i.e. the data length used for the
+ *                initialization of the scatterlist and the data length for the
+ *                decryption operation is identical). For encryption, however,
+ *                the authentication tag is created while encrypting the data.
+ *                The destination buffer must hold sufficient space for the
+ *                ciphertext and the authentication tag while the encryption
+ *                invocation must only point to the plaintext data size. The
+ *                following code snippet illustrates the memory usage
+ *                buffer = kmalloc(ptbuflen + (enc ? authsize : 0));
+ *                sg_init_one(&sg, buffer, ptbuflen + (enc ? authsize : 0));
+ *                aead_request_set_crypt(req, &sg, &sg, ptbuflen, iv);
+ */
 static inline void aead_request_set_crypt(struct aead_request *req,
                                           struct scatterlist *src,
                                           struct scatterlist *dst,
@@ -860,6 +1561,15 @@ static inline void aead_request_set_crypt(struct aead_request *req,
         req->iv = iv;
 }
 
+/**
+ * aead_request_set_assoc() - set the associated data scatter / gather list
+ * @req: request handle
+ * @assoc: associated data scatter / gather list
+ * @assoclen: number of bytes to process from @assoc
+ *
+ * For encryption, the memory is filled with the associated data. For
+ * decryption, the memory must point to the associated data.
+ */
 static inline void aead_request_set_assoc(struct aead_request *req,
                                           struct scatterlist *assoc,
                                           unsigned int assoclen)
@@ -868,6 +1578,36 @@ static inline void aead_request_set_assoc(struct aead_request *req,
         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)
 {
@@ -881,6 +1621,20 @@ static inline struct crypto_blkcipher *crypto_blkcipher_cast(
         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)
 {
@@ -897,11 +1651,25 @@ static inline struct crypto_tfm *crypto_blkcipher_tfm(
         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;
@@ -911,6 +1679,12 @@ static inline int crypto_has_blkcipher(const char *alg_name, u32 type, u32 mask)
         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));
@@ -928,11 +1702,30 @@ static inline struct blkcipher_alg *crypto_blkcipher_alg(
         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)
 {
@@ -962,6 +1755,22 @@ static inline void crypto_blkcipher_clear_flags(struct crypto_blkcipher *tfm,
         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)
 {
@@ -969,6 +1778,24 @@ static inline int crypto_blkcipher_setkey(struct crypto_blkcipher *tfm,
                                                  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,
@@ -978,6 +1805,25 @@ static inline int crypto_blkcipher_encrypt(struct blkcipher_desc *desc,
         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,
@@ -986,6 +1832,23 @@ static inline int crypto_blkcipher_encrypt_iv(struct blkcipher_desc *desc,
         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,
@@ -995,6 +1858,22 @@ static inline int crypto_blkcipher_decrypt(struct blkcipher_desc *desc,
         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,
@@ -1003,18 +1882,54 @@ static inline int crypto_blkcipher_decrypt_iv(struct blkcipher_desc *desc,
         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;
@@ -1026,6 +1941,20 @@ static inline struct crypto_cipher *crypto_cipher_cast(struct crypto_tfm *tfm)
         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)
 {
@@ -1041,11 +1970,25 @@ static inline struct crypto_tfm *crypto_cipher_tfm(struct crypto_cipher *tfm)
         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;
@@ -1060,6 +2003,16 @@ static inline struct cipher_tfm *crypto_cipher_crt(struct crypto_cipher *tfm)
         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));
@@ -1087,6 +2040,22 @@ static inline void crypto_cipher_clear_flags(struct crypto_cipher *tfm,
         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)
 {
@@ -1094,6 +2063,15 @@ static inline int crypto_cipher_setkey(struct crypto_cipher *tfm,
                                                   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)
 {
@@ -1101,6 +2079,15 @@ static inline void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
                                                 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)
 {
@@ -1108,6 +2095,13 @@ static inline void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
                                                 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;
@@ -1120,6 +2114,20 @@ static inline struct crypto_hash *crypto_hash_cast(struct crypto_tfm *tfm)
         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)
 {
@@ -1136,11 +2144,25 @@ static inline struct crypto_tfm *crypto_hash_tfm(struct crypto_hash *tfm)
         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;
@@ -1156,6 +2178,15 @@ static inline struct hash_tfm *crypto_hash_crt(struct crypto_hash *tfm)
         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));
@@ -1166,6 +2197,15 @@ static inline unsigned int crypto_hash_alignmask(struct crypto_hash *tfm)
         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;
@@ -1186,11 +2226,38 @@ static inline void crypto_hash_clear_flags(struct crypto_hash *tfm, u32 flags)
         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)
@@ -1198,11 +2265,39 @@ static inline int crypto_hash_update(struct hash_desc *desc,
         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)
@@ -1210,6 +2305,17 @@ static inline int crypto_hash_digest(struct hash_desc *desc,
         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)
 {
diff --git a/include/net/sock.h b/include/net/sock.h
index c3e83c9a8ab8..2210fec65669 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1593,6 +1593,7 @@ struct sk_buff *sock_alloc_send_pskb(struct sock *sk, unsigned long header_len,
                                      int *errcode, int max_page_order);
 void *sock_kmalloc(struct sock *sk, int size, gfp_t priority);
 void sock_kfree_s(struct sock *sk, void *mem, int size);
+void sock_kzfree_s(struct sock *sk, void *mem, int size);
 void sk_send_sigurg(struct sock *sk);
 
 /*
diff --git a/include/uapi/linux/if_alg.h b/include/uapi/linux/if_alg.h
index 0f9acce5b1ff..f2acd2fde1f3 100644
--- a/include/uapi/linux/if_alg.h
+++ b/include/uapi/linux/if_alg.h
@@ -32,6 +32,8 @@ struct af_alg_iv {
 #define ALG_SET_KEY                     1
 #define ALG_SET_IV                      2
 #define ALG_SET_OP                      3
+#define ALG_SET_AEAD_ASSOCLEN           4
+#define ALG_SET_AEAD_AUTHSIZE           5
 
 /* Operations */
 #define ALG_OP_DECRYPT                  0