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-rw-r--r--Documentation/DocBook/crypto-API.tmpl860
-rw-r--r--Documentation/DocBook/drm.tmpl2
-rw-r--r--Documentation/DocBook/media/v4l/biblio.xml11
-rw-r--r--Documentation/DocBook/media/v4l/dev-sliced-vbi.xml2
-rw-r--r--Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml2
5 files changed, 868 insertions, 9 deletions
diff --git a/Documentation/DocBook/crypto-API.tmpl b/Documentation/DocBook/crypto-API.tmpl
index 04a8c24ead47..efc8d90a9a3f 100644
--- a/Documentation/DocBook/crypto-API.tmpl
+++ b/Documentation/DocBook/crypto-API.tmpl
@@ -509,6 +509,270 @@
select it due to the used type and mask field.
</para>
</sect1>
+
+ <sect1><title>Internal Structure of Kernel Crypto API</title>
+
+ <para>
+ The kernel crypto API has an internal structure where a cipher
+ implementation may use many layers and indirections. This section
+ shall help to clarify how the kernel crypto API uses
+ various components to implement the complete cipher.
+ </para>
+
+ <para>
+ The following subsections explain the internal structure based
+ on existing cipher implementations. The first section addresses
+ the most complex scenario where all other scenarios form a logical
+ subset.
+ </para>
+
+ <sect2><title>Generic AEAD Cipher Structure</title>
+
+ <para>
+ The following ASCII art decomposes the kernel crypto API layers
+ when using the AEAD cipher with the automated IV generation. The
+ shown example is used by the IPSEC layer.
+ </para>
+
+ <para>
+ For other use cases of AEAD ciphers, the ASCII art applies as
+ well, but the caller may not use the GIVCIPHER interface. In
+ this case, the caller must generate the IV.
+ </para>
+
+ <para>
+ The depicted example decomposes the AEAD cipher of GCM(AES) based
+ on the generic C implementations (gcm.c, aes-generic.c, ctr.c,
+ ghash-generic.c, seqiv.c). The generic implementation serves as an
+ example showing the complete logic of the kernel crypto API.
+ </para>
+
+ <para>
+ It is possible that some streamlined cipher implementations (like
+ AES-NI) provide implementations merging aspects which in the view
+ of the kernel crypto API cannot be decomposed into layers any more.
+ In case of the AES-NI implementation, the CTR mode, the GHASH
+ implementation and the AES cipher are all merged into one cipher
+ implementation registered with the kernel crypto API. In this case,
+ the concept described by the following ASCII art applies too. However,
+ the decomposition of GCM into the individual sub-components
+ by the kernel crypto API is not done any more.
+ </para>
+
+ <para>
+ Each block in the following ASCII art is an independent cipher
+ instance obtained from the kernel crypto API. Each block
+ is accessed by the caller or by other blocks using the API functions
+ defined by the kernel crypto API for the cipher implementation type.
+ </para>
+
+ <para>
+ The blocks below indicate the cipher type as well as the specific
+ logic implemented in the cipher.
+ </para>
+
+ <para>
+ The ASCII art picture also indicates the call structure, i.e. who
+ calls which component. The arrows point to the invoked block
+ where the caller uses the API applicable to the cipher type
+ specified for the block.
+ </para>
+
+ <programlisting>
+<![CDATA[
+kernel crypto API | IPSEC Layer
+ |
++-----------+ |
+| | (1)
+| givcipher | <----------------------------------- esp_output
+| (seqiv) | ---+
++-----------+ |
+ | (2)
++-----------+ |
+| | <--+ (2)
+| aead | <----------------------------------- esp_input
+| (gcm) | ------------+
++-----------+ |
+ | (3) | (5)
+ v v
++-----------+ +-----------+
+| | | |
+| ablkcipher| | ahash |
+| (ctr) | ---+ | (ghash) |
++-----------+ | +-----------+
+ |
++-----------+ | (4)
+| | <--+
+| cipher |
+| (aes) |
++-----------+
+]]>
+ </programlisting>
+
+ <para>
+ The following call sequence is applicable when the IPSEC layer
+ triggers an encryption operation with the esp_output function. During
+ configuration, the administrator set up the use of rfc4106(gcm(aes)) as
+ the cipher for ESP. The following call sequence is now depicted in the
+ ASCII art above:
+ </para>
+
+ <orderedlist>
+ <listitem>
+ <para>
+ esp_output() invokes crypto_aead_givencrypt() to trigger an encryption
+ operation of the GIVCIPHER implementation.
+ </para>
+
+ <para>
+ In case of GCM, the SEQIV implementation is registered as GIVCIPHER
+ in crypto_rfc4106_alloc().
+ </para>
+
+ <para>
+ The SEQIV performs its operation to generate an IV where the core
+ function is seqiv_geniv().
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Now, SEQIV uses the AEAD API function calls to invoke the associated
+ AEAD cipher. In our case, during the instantiation of SEQIV, the
+ cipher handle for GCM is provided to SEQIV. This means that SEQIV
+ invokes AEAD cipher operations with the GCM cipher handle.
+ </para>
+
+ <para>
+ During instantiation of the GCM handle, the CTR(AES) and GHASH
+ ciphers are instantiated. The cipher handles for CTR(AES) and GHASH
+ are retained for later use.
+ </para>
+
+ <para>
+ The GCM implementation is responsible to invoke the CTR mode AES and
+ the GHASH cipher in the right manner to implement the GCM
+ specification.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ The GCM AEAD cipher type implementation now invokes the ABLKCIPHER API
+ with the instantiated CTR(AES) cipher handle.
+ </para>
+
+ <para>
+ During instantiation of the CTR(AES) cipher, the CIPHER type
+ implementation of AES is instantiated. The cipher handle for AES is
+ retained.
+ </para>
+
+ <para>
+ That means that the ABLKCIPHER implementation of CTR(AES) only
+ implements the CTR block chaining mode. After performing the block
+ chaining operation, the CIPHER implementation of AES is invoked.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ The ABLKCIPHER of CTR(AES) now invokes the CIPHER API with the AES
+ cipher handle to encrypt one block.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ The GCM AEAD implementation also invokes the GHASH cipher
+ implementation via the AHASH API.
+ </para>
+ </listitem>
+ </orderedlist>
+
+ <para>
+ When the IPSEC layer triggers the esp_input() function, the same call
+ sequence is followed with the only difference that the operation starts
+ with step (2).
+ </para>
+ </sect2>
+
+ <sect2><title>Generic Block Cipher Structure</title>
+ <para>
+ Generic block ciphers follow the same concept as depicted with the ASCII
+ art picture above.
+ </para>
+
+ <para>
+ For example, CBC(AES) is implemented with cbc.c, and aes-generic.c. The
+ ASCII art picture above applies as well with the difference that only
+ step (4) is used and the ABLKCIPHER block chaining mode is CBC.
+ </para>
+ </sect2>
+
+ <sect2><title>Generic Keyed Message Digest Structure</title>
+ <para>
+ Keyed message digest implementations again follow the same concept as
+ depicted in the ASCII art picture above.
+ </para>
+
+ <para>
+ For example, HMAC(SHA256) is implemented with hmac.c and
+ sha256_generic.c. The following ASCII art illustrates the
+ implementation:
+ </para>
+
+ <programlisting>
+<![CDATA[
+kernel crypto API | Caller
+ |
++-----------+ (1) |
+| | <------------------ some_function
+| ahash |
+| (hmac) | ---+
++-----------+ |
+ | (2)
++-----------+ |
+| | <--+
+| shash |
+| (sha256) |
++-----------+
+]]>
+ </programlisting>
+
+ <para>
+ The following call sequence is applicable when a caller triggers
+ an HMAC operation:
+ </para>
+
+ <orderedlist>
+ <listitem>
+ <para>
+ The AHASH API functions are invoked by the caller. The HMAC
+ implementation performs its operation as needed.
+ </para>
+
+ <para>
+ During initialization of the HMAC cipher, the SHASH cipher type of
+ SHA256 is instantiated. The cipher handle for the SHA256 instance is
+ retained.
+ </para>
+
+ <para>
+ At one time, the HMAC implementation requires a SHA256 operation
+ where the SHA256 cipher handle is used.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ The HMAC instance now invokes the SHASH API with the SHA256
+ cipher handle to calculate the message digest.
+ </para>
+ </listitem>
+ </orderedlist>
+ </sect2>
+ </sect1>
</chapter>
<chapter id="Development"><title>Developing Cipher Algorithms</title>
@@ -808,6 +1072,602 @@
</sect1>
</chapter>
+ <chapter id="User"><title>User Space Interface</title>
+ <sect1><title>Introduction</title>
+ <para>
+ The concepts of the kernel crypto API visible to kernel space is fully
+ applicable to the user space interface as well. Therefore, the kernel
+ crypto API high level discussion for the in-kernel use cases applies
+ here as well.
+ </para>
+
+ <para>
+ The major difference, however, is that user space can only act as a
+ consumer and never as a provider of a transformation or cipher algorithm.
+ </para>
+
+ <para>
+ The following covers the user space interface exported by the kernel
+ crypto API. A working example of this description is libkcapi that
+ can be obtained from [1]. That library can be used by user space
+ applications that require cryptographic services from the kernel.
+ </para>
+
+ <para>
+ Some details of the in-kernel kernel crypto API aspects do not
+ apply to user space, however. This includes the difference between
+ synchronous and asynchronous invocations. The user space API call
+ is fully synchronous.
+ </para>
+
+ <para>
+ [1] http://www.chronox.de/libkcapi.html
+ </para>
+
+ </sect1>
+
+ <sect1><title>User Space API General Remarks</title>
+ <para>
+ The kernel crypto API is accessible from user space. Currently,
+ the following ciphers are accessible:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>Message digest including keyed message digest (HMAC, CMAC)</para>
+ </listitem>
+
+ <listitem>
+ <para>Symmetric ciphers</para>
+ </listitem>
+
+ <listitem>
+ <para>AEAD ciphers</para>
+ </listitem>
+
+ <listitem>
+ <para>Random Number Generators</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The interface is provided via socket type using the type AF_ALG.
+ In addition, the setsockopt option type is SOL_ALG. In case the
+ user space header files do not export these flags yet, use the
+ following macros:
+ </para>
+
+ <programlisting>
+#ifndef AF_ALG
+#define AF_ALG 38
+#endif
+#ifndef SOL_ALG
+#define SOL_ALG 279
+#endif
+ </programlisting>
+
+ <para>
+ A cipher is accessed with the same name as done for the in-kernel
+ API calls. This includes the generic vs. unique naming schema for
+ ciphers as well as the enforcement of priorities for generic names.
+ </para>
+
+ <para>
+ To interact with the kernel crypto API, a socket must be
+ created by the user space application. User space invokes the cipher
+ operation with the send()/write() system call family. The result of the
+ cipher operation is obtained with the read()/recv() system call family.
+ </para>
+
+ <para>
+ The following API calls assume that the socket descriptor
+ is already opened by the user space application and discusses only
+ the kernel crypto API specific invocations.
+ </para>
+
+ <para>
+ To initialize the socket interface, the following sequence has to
+ be performed by the consumer:
+ </para>
+
+ <orderedlist>
+ <listitem>
+ <para>
+ Create a socket of type AF_ALG with the struct sockaddr_alg
+ parameter specified below for the different cipher types.
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Invoke bind with the socket descriptor
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ Invoke accept with the socket descriptor. The accept system call
+ returns a new file descriptor that is to be used to interact with
+ the particular cipher instance. When invoking send/write or recv/read
+ system calls to send data to the kernel or obtain data from the
+ kernel, the file descriptor returned by accept must be used.
+ </para>
+ </listitem>
+ </orderedlist>
+ </sect1>
+
+ <sect1><title>In-place Cipher operation</title>
+ <para>
+ Just like the in-kernel operation of the kernel crypto API, the user
+ space interface allows the cipher operation in-place. That means that
+ the input buffer used for the send/write system call and the output
+ buffer used by the read/recv system call may be one and the same.
+ This is of particular interest for symmetric cipher operations where a
+ copying of the output data to its final destination can be avoided.
+ </para>
+
+ <para>
+ If a consumer on the other hand wants to maintain the plaintext and
+ the ciphertext in different memory locations, all a consumer needs
+ to do is to provide different memory pointers for the encryption and
+ decryption operation.
+ </para>
+ </sect1>
+
+ <sect1><title>Message Digest API</title>
+ <para>
+ The message digest type to be used for the cipher operation is
+ selected when invoking the bind syscall. bind requires the caller
+ to provide a filled struct sockaddr data structure. This data
+ structure must be filled as follows:
+ </para>
+
+ <programlisting>
+struct sockaddr_alg sa = {
+ .salg_family = AF_ALG,
+ .salg_type = "hash", /* this selects the hash logic in the kernel */
+ .salg_name = "sha1" /* this is the cipher name */
+};
+ </programlisting>
+
+ <para>
+ The salg_type value "hash" applies to message digests and keyed
+ message digests. Though, a keyed message digest is referenced by
+ the appropriate salg_name. Please see below for the setsockopt
+ interface that explains how the key can be set for a keyed message
+ digest.
+ </para>
+
+ <para>
+ Using the send() system call, the application provides the data that
+ should be processed with the message digest. The send system call
+ allows the following flags to be specified:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ MSG_MORE: If this flag is set, the send system call acts like a
+ message digest update function where the final hash is not
+ yet calculated. If the flag is not set, the send system call
+ calculates the final message digest immediately.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ With the recv() system call, the application can read the message
+ digest from the kernel crypto API. If the buffer is too small for the
+ message digest, the flag MSG_TRUNC is set by the kernel.
+ </para>
+
+ <para>
+ In order to set a message digest key, the calling application must use
+ the setsockopt() option of ALG_SET_KEY. If the key is not set the HMAC
+ operation is performed without the initial HMAC state change caused by
+ the key.
+ </para>
+ </sect1>
+
+ <sect1><title>Symmetric Cipher API</title>
+ <para>
+ The operation is very similar to the message digest discussion.
+ During initialization, the struct sockaddr data structure must be
+ filled as follows:
+ </para>
+
+ <programlisting>
+struct sockaddr_alg sa = {
+ .salg_family = AF_ALG,
+ .salg_type = "skcipher", /* this selects the symmetric cipher */
+ .salg_name = "cbc(aes)" /* this is the cipher name */
+};
+ </programlisting>
+
+ <para>
+ Before data can be sent to the kernel using the write/send system
+ call family, the consumer must set the key. The key setting is
+ described with the setsockopt invocation below.
+ </para>
+
+ <para>
+ Using the sendmsg() system call, the application provides the data that should be processed for encryption or decryption. In addition, the IV is
+ specified with the data structure provided by the sendmsg() system call.
+ </para>
+
+ <para>
+ The sendmsg system call parameter of struct msghdr is embedded into the
+ struct cmsghdr data structure. See recv(2) and cmsg(3) for more
+ information on how the cmsghdr data structure is used together with the
+ send/recv system call family. That cmsghdr data structure holds the
+ following information specified with a separate header instances:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ specification of the cipher operation type with one of these flags:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <para>ALG_OP_ENCRYPT - encryption of data</para>
+ </listitem>
+ <listitem>
+ <para>ALG_OP_DECRYPT - decryption of data</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+
+ <listitem>
+ <para>
+ specification of the IV information marked with the flag ALG_SET_IV
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The send system call family allows the following flag to be specified:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ MSG_MORE: If this flag is set, the send system call acts like a
+ cipher update function where more input data is expected
+ with a subsequent invocation of the send system call.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ Note: The kernel reports -EINVAL for any unexpected data. The caller
+ must make sure that all data matches the constraints given in
+ /proc/crypto for the selected cipher.
+ </para>
+
+ <para>
+ With the recv() system call, the application can read the result of
+ the cipher operation from the kernel crypto API. The output buffer
+ must be at least as large as to hold all blocks of the encrypted or
+ decrypted data. If the output data size is smaller, only as many
+ blocks are returned that fit into that output buffer size.
+ </para>
+ </sect1>
+
+ <sect1><title>AEAD Cipher API</title>
+ <para>
+ The operation is very similar to the symmetric cipher discussion.
+ During initialization, the struct sockaddr data structure must be
+ filled as follows:
+ </para>
+
+ <programlisting>
+struct sockaddr_alg sa = {
+ .salg_family = AF_ALG,
+ .salg_type = "aead", /* this selects the symmetric cipher */
+ .salg_name = "gcm(aes)" /* this is the cipher name */
+};
+ </programlisting>
+
+ <para>
+ Before data can be sent to the kernel using the write/send system
+ call family, the consumer must set the key. The key setting is
+ described with the setsockopt invocation below.
+ </para>
+
+ <para>
+ In addition, before data can be sent to the kernel using the
+ write/send system call family, the consumer must set the authentication
+ tag size. To set the authentication tag size, the caller must use the
+ setsockopt invocation described below.
+ </para>
+
+ <para>
+ Using the sendmsg() system call, the application provides the data that should be processed for encryption or decryption. In addition, the IV is
+ specified with the data structure provided by the sendmsg() system call.
+ </para>
+
+ <para>
+ The sendmsg system call parameter of struct msghdr is embedded into the
+ struct cmsghdr data structure. See recv(2) and cmsg(3) for more
+ information on how the cmsghdr data structure is used together with the
+ send/recv system call family. That cmsghdr data structure holds the
+ following information specified with a separate header instances:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ specification of the cipher operation type with one of these flags:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <para>ALG_OP_ENCRYPT - encryption of data</para>
+ </listitem>
+ <listitem>
+ <para>ALG_OP_DECRYPT - decryption of data</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+
+ <listitem>
+ <para>
+ specification of the IV information marked with the flag ALG_SET_IV
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ specification of the associated authentication data (AAD) with the
+ flag ALG_SET_AEAD_ASSOCLEN. The AAD is sent to the kernel together
+ with the plaintext / ciphertext. See below for the memory structure.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The send system call family allows the following flag to be specified:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ MSG_MORE: If this flag is set, the send system call acts like a
+ cipher update function where more input data is expected
+ with a subsequent invocation of the send system call.
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ Note: The kernel reports -EINVAL for any unexpected data. The caller
+ must make sure that all data matches the constraints given in
+ /proc/crypto for the selected cipher.
+ </para>
+
+ <para>
+ With the recv() system call, the application can read the result of
+ the cipher operation from the kernel crypto API. The output buffer
+ must be at least as large as defined with the memory structure below.
+ If the output data size is smaller, the cipher operation is not performed.
+ </para>
+
+ <para>
+ The authenticated decryption operation may indicate an integrity error.
+ Such breach in integrity is marked with the -EBADMSG error code.
+ </para>
+
+ <sect2><title>AEAD Memory Structure</title>
+ <para>
+ The AEAD cipher operates with the following information that
+ is communicated between user and kernel space as one data stream:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>plaintext or ciphertext</para>
+ </listitem>
+
+ <listitem>
+ <para>associated authentication data (AAD)</para>
+ </listitem>
+
+ <listitem>
+ <para>authentication tag</para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The sizes of the AAD and the authentication tag are provided with
+ the sendmsg and setsockopt calls (see there). As the kernel knows
+ the size of the entire data stream, the kernel is now able to
+ calculate the right offsets of the data components in the data
+ stream.
+ </para>
+
+ <para>
+ The user space caller must arrange the aforementioned information
+ in the following order:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ AEAD encryption input: AAD || plaintext
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ AEAD decryption input: AAD || ciphertext || authentication tag
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ <para>
+ The output buffer the user space caller provides must be at least as
+ large to hold the following data:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ AEAD encryption output: ciphertext || authentication tag
+ </para>
+ </listitem>
+
+ <listitem>
+ <para>
+ AEAD decryption output: plaintext
+ </para>
+ </listitem>
+ </itemizedlist>
+ </sect2>
+ </sect1>
+
+ <sect1><title>Random Number Generator API</title>
+ <para>
+ Again, the operation is very similar to the other APIs.
+ During initialization, the struct sockaddr data structure must be
+ filled as follows:
+ </para>
+
+ <programlisting>
+struct sockaddr_alg sa = {
+ .salg_family = AF_ALG,
+ .salg_type = "rng", /* this selects the symmetric cipher */
+ .salg_name = "drbg_nopr_sha256" /* this is the cipher name */
+};
+ </programlisting>
+
+ <para>
+ Depending on the RNG type, the RNG must be seeded. The seed is provided
+ using the setsockopt interface to set the key. For example, the
+ ansi_cprng requires a seed. The DRBGs do not require a seed, but
+ may be seeded.
+ </para>
+
+ <para>
+ Using the read()/recvmsg() system calls, random numbers can be obtained.
+ The kernel generates at most 128 bytes in one call. If user space
+ requires more data, multiple calls to read()/recvmsg() must be made.
+ </para>
+
+ <para>
+ WARNING: The user space caller may invoke the initially mentioned
+ accept system call multiple times. In this case, the returned file
+ descriptors have the same state.
+ </para>
+
+ </sect1>
+
+ <sect1><title>Zero-Copy Interface</title>
+ <para>
+ In addition to the send/write/read/recv system call familty, the AF_ALG
+ interface can be accessed with the zero-copy interface of splice/vmsplice.
+ As the name indicates, the kernel tries to avoid a copy operation into
+ kernel space.
+ </para>
+
+ <para>
+ The zero-copy operation requires data to be aligned at the page boundary.
+ Non-aligned data can be used as well, but may require more operations of
+ the kernel which would defeat the speed gains obtained from the zero-copy
+ interface.
+ </para>
+
+ <para>
+ The system-interent limit for the size of one zero-copy operation is
+ 16 pages. If more data is to be sent to AF_ALG, user space must slice
+ the input into segments with a maximum size of 16 pages.
+ </para>
+
+ <para>
+ Zero-copy can be used with the following code example (a complete working
+ example is provided with libkcapi):
+ </para>
+
+ <programlisting>
+int pipes[2];
+
+pipe(pipes);
+/* input data in iov */
+vmsplice(pipes[1], iov, iovlen, SPLICE_F_GIFT);
+/* opfd is the file descriptor returned from accept() system call */
+splice(pipes[0], NULL, opfd, NULL, ret, 0);
+read(opfd, out, outlen);
+ </programlisting>
+
+ </sect1>
+
+ <sect1><title>Setsockopt Interface</title>
+ <para>
+ In addition to the read/recv and send/write system call handling
+ to send and retrieve data subject to the cipher operation, a consumer
+ also needs to set the additional information for the cipher operation.
+ This additional information is set using the setsockopt system call
+ that must be invoked with the file descriptor of the open cipher
+ (i.e. the file descriptor returned by the accept system call).
+ </para>
+
+ <para>
+ Each setsockopt invocation must use the level SOL_ALG.
+ </para>
+
+ <para>
+ The setsockopt interface allows setting the following data using
+ the mentioned optname:
+ </para>
+
+ <itemizedlist>
+ <listitem>
+ <para>
+ ALG_SET_KEY -- Setting the key. Key setting is applicable to:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <para>the skcipher cipher type (symmetric ciphers)</para>
+ </listitem>
+ <listitem>
+ <para>the hash cipher type (keyed message digests)</para>
+ </listitem>
+ <listitem>
+ <para>the AEAD cipher type</para>
+ </listitem>
+ <listitem>
+ <para>the RNG cipher type to provide the seed</para>
+ </listitem>
+ </itemizedlist>
+ </listitem>
+
+ <listitem>
+ <para>
+ ALG_SET_AEAD_AUTHSIZE -- Setting the authentication tag size
+ for AEAD ciphers. For a encryption operation, the authentication
+ tag of the given size will be generated. For a decryption operation,
+ the provided ciphertext is assumed to contain an authentication tag
+ of the given size (see section about AEAD memory layout below).
+ </para>
+ </listitem>
+ </itemizedlist>
+
+ </sect1>
+
+ <sect1><title>User space API example</title>
+ <para>
+ Please see [1] for libkcapi which provides an easy-to-use wrapper
+ around the aforementioned Netlink kernel interface. [1] also contains
+ a test application that invokes all libkcapi API calls.
+ </para>
+
+ <para>
+ [1] http://www.chronox.de/libkcapi.html
+ </para>
+
+ </sect1>
+
+ </chapter>
+
<chapter id="API"><title>Programming Interface</title>
<sect1><title>Block Cipher Context Data Structures</title>
!Pinclude/linux/crypto.h Block Cipher Context Data Structures
diff --git a/Documentation/DocBook/drm.tmpl b/Documentation/DocBook/drm.tmpl
index f4976cd7b32b..9765a4c0829d 100644
--- a/Documentation/DocBook/drm.tmpl
+++ b/Documentation/DocBook/drm.tmpl
@@ -1293,7 +1293,7 @@ int max_width, max_height;</synopsis>
</para>
<para>
If a page flip can be successfully scheduled the driver must set the
- <code>drm_crtc-&lt;fb</code> field to the new framebuffer pointed to
+ <code>drm_crtc-&gt;fb</code> field to the new framebuffer pointed to
by <code>fb</code>. This is important so that the reference counting
on framebuffers stays balanced.
</para>
diff --git a/Documentation/DocBook/media/v4l/biblio.xml b/Documentation/DocBook/media/v4l/biblio.xml
index 7ff01a23c2fe..fdee6b3f3eca 100644
--- a/Documentation/DocBook/media/v4l/biblio.xml
+++ b/Documentation/DocBook/media/v4l/biblio.xml
@@ -1,14 +1,13 @@
<bibliography>
<title>References</title>
- <biblioentry id="eia608">
- <abbrev>EIA&nbsp;608-B</abbrev>
+ <biblioentry id="cea608">
+ <abbrev>CEA&nbsp;608-E</abbrev>
<authorgroup>
- <corpauthor>Electronic Industries Alliance (<ulink
-url="http://www.eia.org">http://www.eia.org</ulink>)</corpauthor>
+ <corpauthor>Consumer Electronics Association (<ulink
+url="http://www.ce.org">http://www.ce.org</ulink>)</corpauthor>
</authorgroup>
- <title>EIA 608-B "Recommended Practice for Line 21 Data
-Service"</title>
+ <title>CEA-608-E R-2014 "Line 21 Data Services"</title>
</biblioentry>
<biblioentry id="en300294">
diff --git a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml b/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
index 7a8bf3011ee9..0aec62ed2bf8 100644
--- a/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
+++ b/Documentation/DocBook/media/v4l/dev-sliced-vbi.xml
@@ -254,7 +254,7 @@ ETS&nbsp;300&nbsp;231, lsb first transmitted.</entry>
<row>
<entry><constant>V4L2_SLICED_CAPTION_525</constant></entry>
<entry>0x1000</entry>
- <entry><xref linkend="eia608" /></entry>
+ <entry><xref linkend="cea608" /></entry>
<entry>NTSC line 21, 284 (second field 21)</entry>
<entry>Two bytes in transmission order, including parity
bit, lsb first transmitted.</entry>
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml b/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml
index bd015d1563ff..d05623c55403 100644
--- a/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml
+++ b/Documentation/DocBook/media/v4l/vidioc-g-sliced-vbi-cap.xml
@@ -205,7 +205,7 @@ ETS&nbsp;300&nbsp;231, lsb first transmitted.</entry>
<row>
<entry><constant>V4L2_SLICED_CAPTION_525</constant></entry>
<entry>0x1000</entry>
- <entry><xref linkend="eia608" /></entry>
+ <entry><xref linkend="cea608" /></entry>
<entry>NTSC line 21, 284 (second field 21)</entry>
<entry>Two bytes in transmission order, including parity
bit, lsb first transmitted.</entry>