Commit Graph

60 Commits

Author SHA1 Message Date
Herbert Xu
fe869cdb89 crypto: algif_hash - User-space interface for hash operations
This patch adds the af_alg plugin for hash, corresponding to
the ahash kernel operation type.

Keys can optionally be set through the setsockopt interface.

Each sendmsg call will finalise the hash unless sent with a MSG_MORE
flag.

Partial hash states can be cloned using accept(2).

The interface is completely synchronous, all operations will
complete prior to the system call returning.

Both sendmsg(2) and splice(2) support reading the user-space
data directly without copying (except that the Crypto API itself
may copy the data if alignment is off).

For now only the splice(2) interface supports performing digest
instead of init/update/final.  In future the sendmsg(2) interface
will also be modified to use digest/finup where possible so that
hardware that cannot return a partial hash state can still benefit
from this interface.

Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Martin Willi <martin@strongswan.org>
2010-11-19 17:47:58 +08:00
Herbert Xu
03c8efc1ff crypto: af_alg - User-space interface for Crypto API
This patch creates the backbone of the user-space interface for
the Crypto API, through a new socket family AF_ALG.

Each session corresponds to one or more connections obtained from
that socket.  The number depends on the number of inputs/outputs
of that particular type of operation.  For most types there will
be a s ingle connection/file descriptor that is used for both input
and output.  AEAD is one of the few that require two inputs.

Each algorithm type will provide its own implementation that plugs
into af_alg.  They're keyed using a string such as "skcipher" or
"hash".

IOW this patch only contains the boring bits that is required
to hold everything together.

Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Martin Willi <martin@strongswan.org>
2010-11-19 17:47:57 +08:00
Joachim Fritschi
5b04fc1703 crypto: twofish: Rename twofish to twofish_generic and add an alias
This fixes the broken autoloading of the corresponding twofish assembler
ciphers on x86 and x86_64 if they are available. The module name of the
generic implementation was in conflict with the alias in the assembler
modules. The generic twofish c implementation is renamed to
twofish_generic according to the other algorithms with assembler
implementations and an module alias is added for 'twofish'. You can now
load 'twofish' giving you the best implementation by priority,
'twofish-generic' to get the c implementation or 'twofish-asm' to get
the assembler version of cipher.

Signed-off-by: Joachim Fritschi <jfritschi@freenet.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-03 21:02:51 +10:00
Herbert Xu
bc94e59662 crypto: pcomp - Fix illegal Kconfig configuration
The PCOMP Kconfig entry current allows the following combination
which is illegal:

ZLIB=y
PCOMP=y
ALGAPI=m
ALGAPI2=y
MANAGER=m
MANAGER2=m

This patch fixes this by adding PCOMP2 so that PCOMP can select
ALGAPI to propagate the setting to MANAGER2.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-03 20:33:06 +10:00
Steffen Klassert
5068c7a883 crypto: pcrypt - Add pcrypt crypto parallelization wrapper
This patch adds a parallel crypto template that takes a crypto
algorithm and converts it to process the crypto transforms in
parallel. For the moment only aead algorithms are supported.

Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-01-07 15:57:19 +11:00
Shane Wang
f1939f7c56 crypto: vmac - New hash algorithm for intel_txt support
This patch adds VMAC (a fast MAC) support into crypto framework.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Joseph Cihula <joseph.cihula@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-09-02 20:05:22 +10:00
Huang Ying
2cdc6899a8 crypto: ghash - Add GHASH digest algorithm for GCM
GHASH is implemented as a shash algorithm. The actual implementation
is copied from gcm.c. This makes it possible to add
architecture/hardware accelerated GHASH implementation.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-08-06 15:32:38 +10:00
Herbert Xu
6941c3a0aa crypto: hash - Remove legacy hash/digest implementaion
This patch removes the implementation of hash and digest now that
no algorithms use them anymore.  The interface though will remain
until the users are converted across.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-07-14 12:58:07 +08:00
Geert Uytterhoeven
bf68e65ec9 crypto: zlib - New zlib crypto module, using pcomp
Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Cc: James Morris <jmorris@namei.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-03-04 15:16:19 +08:00
Geert Uytterhoeven
a1d2f09544 crypto: compress - Add pcomp interface
The current "comp" crypto interface supports one-shot (de)compression only,
i.e. the whole data buffer to be (de)compressed must be passed at once, and
the whole (de)compressed data buffer will be received at once.
In several use-cases (e.g. compressed file systems that store files in big
compressed blocks), this workflow is not suitable.
Furthermore, the "comp" type doesn't provide for the configuration of
(de)compression parameters, and always allocates workspace memory for both
compression and decompression, which may waste memory.

To solve this, add a "pcomp" partial (de)compression interface that provides
the following operations:
  - crypto_compress_{init,update,final}() for compression,
  - crypto_decompress_{init,update,final}() for decompression,
  - crypto_{,de}compress_setup(), to configure (de)compression parameters
    (incl. allocating workspace memory).

The (de)compression methods take a struct comp_request, which was mimicked
after the z_stream object in zlib, and contains buffer pointer and length
pairs for input and output.

The setup methods take an opaque parameter pointer and length pair. Parameters
are supposed to be encoded using netlink attributes, whose meanings depend on
the actual (name of the) (de)compression algorithm.

Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-03-04 15:05:33 +08:00
Huang Ying
25c38d3fb9 crypto: api - Use dedicated workqueue for crypto subsystem
Use dedicated workqueue for crypto subsystem

A dedicated workqueue named kcrypto_wq is created to be used by crypto
subsystem. The system shared keventd_wq is not suitable for
encryption/decryption, because of potential starvation problem.

Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-02-19 14:33:40 +08:00
Herbert Xu
7b5a080b3c crypto: hash - Add shash interface
The shash interface replaces the current synchronous hash interface.
It improves over hash in two ways.  Firstly shash is reentrant,
meaning that the same tfm may be used by two threads simultaneously
as all hashing state is stored in a local descriptor.

The other enhancement is that shash no longer takes scatter list
entries.  This is because shash is specifically designed for
synchronous algorithms and as such scatter lists are unnecessary.

All existing hash users will be converted to shash once the
algorithms have been completely converted.

There is also a new finup function that combines update with final.
This will be extended to ahash once the algorithm conversion is
done.

This is also the first time that an algorithm type has their own
registration function.  Existing algorithm types will be converted
to this way in due course.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25 11:01:26 +11:00
Herbert Xu
6a0fcbb4da crypto: api - Disallow cryptomgr as a module if algorithms are built-in
If we have at least one algorithm built-in then it no longer makes
sense to have the testing framework, and hence cryptomgr to be a
module.  It should be either on or off, i.e., built-in or disabled.

This just happens to stop a potential runaway modprobe loop that
seems to trigger on at least one distro.

With fixes from Evgeniy Polyakov.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-10 23:29:44 +11:00
Neil Horman
17f0f4a47d crypto: rng - RNG interface and implementation
This patch adds a random number generator interface as well as a
cryptographic pseudo-random number generator based on AES.  It is
meant to be used in cases where a deterministic CPRNG is required.

One of the first applications will be as an input in the IPsec IV
generation process.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29 15:50:04 +10:00
Neil Horman
ccb778e184 crypto: api - Add fips_enable flag
Add the ability to turn FIPS-compliant mode on or off at boot

In order to be FIPS compliant, several check may need to be preformed that may
be construed as unusefull in a non-compliant mode.  This patch allows us to set
a kernel flag incating that we are running in a fips-compliant mode from boot
up.  It also exports that mode information to user space via a sysctl
(/proc/sys/crypto/fips_enabled).

Tested successfully by me.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29 15:50:02 +10:00
Herbert Xu
5be5e667a9 crypto: skcipher - Move IV generators into their own modules
This patch moves the default IV generators into their own modules
in order to break a dependency loop between cryptomgr, rng, and
blkcipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29 15:50:00 +10:00
Herbert Xu
da7f033ddc crypto: cryptomgr - Add test infrastructure
This patch moves the newly created alg_test infrastructure into
cryptomgr.  This shall allow us to use it for testing at algorithm
registrations.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-08-29 15:49:55 +10:00
Herbert Xu
7890ea1f95 Revert crypto: prng - Deterministic CPRNG
This patch is clearly not ready yet for prime time.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-15 23:46:24 +08:00
Neil Horman
b8454eebe3 crypto: prng - Deterministic CPRNG
This patch adds a cryptographic pseudo-random number generator
based on CTR(AES-128).  It is meant to be used in cases where a
deterministic CPRNG is required.

One of the first applications will be as an input in the IPsec IV
generation process.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:18 +08:00
Loc Ho
004a403c2e [CRYPTO] hash: Add asynchronous hash support
This patch adds asynchronous hash and digest support.

Signed-off-by: Loc Ho <lho@amcc.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:13 +08:00
Adrian-Ken Rueegsegger
c555c28d9d [CRYPTO] ripemd: Add support for RIPEMD-256 and RIPEMD-320
This patch adds support for the extended RIPEMD hash
algorithms RIPEMD-256 and RIPEMD-320.

Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:13 +08:00
Adrian-Ken Rueegsegger
c6580eb8b1 [CRYPTO] ripemd: Add support for RIPEMD hash algorithms
This patch adds support for RIPEMD-128 and RIPEMD-160
hash algorithms.

Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:09 +08:00
Sebastian Siewior
c3715cb90f [CRYPTO] api: Make the crypto subsystem fully modular
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21 10:19:23 +08:00
Kevin Coffman
76cb952179 [CRYPTO] cts: Add CTS mode required for Kerberos AES support
Implement CTS wrapper for CBC mode required for support of AES
encryption support for Kerberos (rfc3962).

Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21 10:19:23 +08:00
Jan Glauber
78f8b3a240 [CRYPTO] sha512: Rename sha512 to sha512_generic
Rename sha512 to sha512_generic and add a MODULE_ALIAS for sha512
so all sha512 implementations can be loaded automatically.

Keep the broken tabs so git recognizes this as a rename.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-04-21 10:19:21 +08:00
Herbert Xu
76fc60a2e3 [CRYPTO] skcipher: Move chainiv/seqiv into crypto_blkcipher module
For compatibility with dm-crypt initramfs setups it is useful to merge
chainiv/seqiv into the crypto_blkcipher module.  Since they're required
by most algorithms anyway this is an acceptable trade-off.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-02-23 11:12:06 +08:00
Joy Latten
4a49b499df [CRYPTO] ccm: Added CCM mode
This patch adds Counter with CBC-MAC (CCM) support.
RFC 3610 and NIST Special Publication 800-38C were referenced.

Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:53 +11:00
Herbert Xu
0a270321db [CRYPTO] seqiv: Add Sequence Number IV Generator
This generator generates an IV based on a sequence number by xoring it
with a salt.  This algorithm is mainly useful for CTR and similar modes.

This patch also sets it as the default IV generator for ctr.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:48 +11:00
Herbert Xu
806d183aa6 [CRYPTO] eseqiv: Add Encrypted Sequence Number IV Generator
This generator generates an IV based on a sequence number by xoring it
with a salt and then encrypting it with the same key as used to encrypt
the plain text.  This algorithm requires that the block size be equal
to the IV size.  It is mainly useful for CBC.

It has one noteworthy property that for IPsec the IV happens to lie
just before the plain text so the IV generation simply increases the
number of encrypted blocks by one.  Therefore the cost of this generator
is entirely dependent on the speed of the underlying cipher.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:45 +11:00
Herbert Xu
7f47073911 [CRYPTO] chainiv: Add chain IV generator
The chain IV generator is the one we've been using in the IPsec stack.
It simply starts out with a random IV, then uses the last block of each
encrypted packet's cipher text as the IV for the next packet.

It can only be used by synchronous ciphers since we have to make sure
that we don't start the encryption of the next packet until the last
one has completed.

It does have the advantage of using very little CPU time since it doesn't
have to generate anything at all.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:44 +11:00
Herbert Xu
653ebd9c85 [CRYPTO] blkcipher: Merge ablkcipher and blkcipher into one option/module
With the impending addition of the givcipher type, both blkcipher and
ablkcipher algorithms will use it to create givcipher objects.  As such
it no longer makes sense to split the system between ablkcipher and
blkcipher.  In particular, both ablkcipher.c and blkcipher.c would need
to use the givcipher type which has to reside in ablkcipher.c since it
shares much code with it.

This patch merges the two Kconfig options as well as the modules into one.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:41 +11:00
Zoltan Sogor
0b77abb3b2 [CRYPTO] lzo: Add LZO compression algorithm support
Add LZO compression algorithm support

Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:35 +11:00
Mikko Herranen
28db8e3e38 [CRYPTO] gcm: New algorithm
Add GCM/GMAC support to cryptoapi.

GCM (Galois/Counter Mode) is an AEAD mode of operations for any block cipher
with a block size of 16.  The typical example is AES-GCM.

Signed-off-by: Mikko Herranen <mh1@iki.fi>
Reviewed-by: Mika Kukkonen <mika.kukkonen@nsn.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:23 +11:00
Tan Swee Heng
2407d60872 [CRYPTO] salsa20: Salsa20 stream cipher
This patch implements the Salsa20 stream cipher using the blkcipher interface.

The core cipher code comes from Daniel Bernstein's submission to eSTREAM:
  http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/ref/

The test vectors comes from:
  http://www.ecrypt.eu.org/stream/svn/viewcvs.cgi/ecrypt/trunk/submissions/salsa20/full/

It has been tested successfully with "modprobe tcrypt mode=34" on an
UML instance.

Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:15 +11:00
Joy Latten
23e353c8a6 [CRYPTO] ctr: Add CTR (Counter) block cipher mode
This patch implements CTR mode for IPsec.
It is based off of RFC 3686.

Please note:
1. CTR turns a block cipher into a stream cipher.
Encryption is done in blocks, however the last block
may be a partial block.

A "counter block" is encrypted, creating a keystream
that is xor'ed with the plaintext. The counter portion
of the counter block is incremented after each block
of plaintext is encrypted.
Decryption is performed in same manner.

2. The CTR counterblock is composed of,
        nonce + IV + counter

The size of the counterblock is equivalent to the
blocksize of the cipher.
        sizeof(nonce) + sizeof(IV) + sizeof(counter) = blocksize

The CTR template requires the name of the cipher
algorithm, the sizeof the nonce, and the sizeof the iv.
        ctr(cipher,sizeof_nonce,sizeof_iv)

So for example,
        ctr(aes,4,8)
specifies the counterblock will be composed of 4 bytes
from a nonce, 8 bytes from the iv, and 4 bytes for counter
since aes has a blocksize of 16 bytes.

3. The counter portion of the counter block is stored
in big endian for conformance to rfc 3686.

Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:01 +11:00
Sebastian Siewior
ad5d27899f [CRYPTO] sha: Load the SHA[1|256] module by an alias
Loading the crypto algorithm by the alias instead of by module directly
has the advantage that all possible implementations of this algorithm
are loaded automatically and the crypto API can choose the best one
depending on its priority.

Additionally it ensures that the generic implementation as well as the
HW driver (if available) is loaded in case the HW driver needs the
generic version as fallback in corner cases.

Also remove the probe for sha1 in padlock's init code.

Quote from Herbert:
  The probe is actually pointless since we can always probe when
  the algorithm is actually used which does not lead to dead-locks
  like this.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:50 -07:00
Sebastian Siewior
f8246af005 [CRYPTO] aes: Rename aes to aes-generic
Loading the crypto algorithm by the alias instead of by module directly
has the advantage that all possible implementations of this algorithm
are loaded automatically and the crypto API can choose the best one
depending on its priority.

Additionally it ensures that the generic implementation as well as the
HW driver (if available) is loaded in case the HW driver needs the
generic version as fallback in corner cases.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:49 -07:00
Sebastian Siewior
c5a511f1cd [CRYPTO] des: Rename des to des-generic
Loading the crypto algorithm by the alias instead of by module directly
has the advantage that all possible implementations of this algorithm
are loaded automatically and the crypto API can choose the best one
depending on its priority.

Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:49 -07:00
Rik Snel
f19f5111c9 [CRYPTO] xts: XTS blockcipher mode implementation without partial blocks
XTS currently considered to be the successor of the LRW mode by the IEEE1619
workgroup. LRW was discarded, because it was not secure if the encyption key
itself is encrypted with LRW.

XTS does not have this problem. The implementation is pretty straightforward,
a new function was added to gf128mul to handle GF(128) elements in ble format.
Four testvectors from the specification
	http://grouper.ieee.org/groups/1619/email/pdf00086.pdf
were added, and they verify on my system.

Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:45 -07:00
Herbert Xu
3c09f17c3d [CRYPTO] aead: Add authenc
This patch adds the authenc algorithm which constructs an AEAD algorithm
from an asynchronous block cipher and a hash.  The construction is done
by concatenating the encrypted result from the cipher with the output
from the hash, as is used by the IPsec ESP protocol.

The authenc algorithm exists as a template with four parameters:

	authenc(auth, authsize, enc, enckeylen).

The authentication algorithm, the authentication size (i.e., truncating
the output of the authentication algorithm), the encryption algorithm,
and the encryption key length.  Both the size field and the key length
field are in bytes.  For example, AES-128 with SHA1-HMAC would be
represented by

	authenc(hmac(sha1), 12, cbc(aes), 16)

The key for the authenc algorithm is the concatenation of the keys for
the authentication algorithm with the encryption algorithm.  For the
above example, if a key of length 36 bytes is given, then hmac(sha1)
would receive the first 20 bytes while the last 16 would be given to
cbc(aes).

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:43 -07:00
Herbert Xu
e962a653f3 [CRYPTO] api: Move scatterwalk into algapi
The scatterwalk code is only used by algorithms that can be built as
a module.  Therefore we can move it into algapi.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:41 -07:00
Herbert Xu
1ae978208e [CRYPTO] api: Add aead crypto type
This patch adds crypto_aead which is the interface for AEAD
(Authenticated Encryption with Associated Data) algorithms.

AEAD algorithms perform authentication and encryption in one
step.  Traditionally users (such as IPsec) would use two
different crypto algorithms to perform these.  With AEAD
this comes down to one algorithm and one operation.

Of course if traditional algorithms were used we'd still
be doing two operations underneath.  However, real AEAD
algorithms may allow the underlying operations to be
optimised as well.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:39 -07:00
Hye-Shik Chang
e2ee95b8c6 [CRYPTO] seed: New cipher algorithm
This patch adds support for the SEED cipher (RFC4269).

This patch have been used in few VPN appliance vendors in Korea for
several years.  And it was verified by KISA, who developed the
algorithm itself.

As its importance in Korean banking industry, it would be great
if linux incorporates the support.

Signed-off-by: Hye-Shik Chang <perky@FreeBSD.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10 16:55:38 -07:00
Dan Williams
9bc89cd82d async_tx: add the async_tx api
The async_tx api provides methods for describing a chain of asynchronous
bulk memory transfers/transforms with support for inter-transactional
dependencies.  It is implemented as a dmaengine client that smooths over
the details of different hardware offload engine implementations.  Code
that is written to the api can optimize for asynchronous operation and the
api will fit the chain of operations to the available offload resources. 
 
	I imagine that any piece of ADMA hardware would register with the
	'async_*' subsystem, and a call to async_X would be routed as
	appropriate, or be run in-line. - Neil Brown

async_tx exploits the capabilities of struct dma_async_tx_descriptor to
provide an api of the following general format:

struct dma_async_tx_descriptor *
async_<operation>(..., struct dma_async_tx_descriptor *depend_tx,
			dma_async_tx_callback cb_fn, void *cb_param)
{
	struct dma_chan *chan = async_tx_find_channel(depend_tx, <operation>);
	struct dma_device *device = chan ? chan->device : NULL;
	int int_en = cb_fn ? 1 : 0;
	struct dma_async_tx_descriptor *tx = device ?
		device->device_prep_dma_<operation>(chan, len, int_en) : NULL;

	if (tx) { /* run <operation> asynchronously */
		...
		tx->tx_set_dest(addr, tx, index);
		...
		tx->tx_set_src(addr, tx, index);
		...
		async_tx_submit(chan, tx, flags, depend_tx, cb_fn, cb_param);
	} else { /* run <operation> synchronously */
		...
		<operation>
		...
		async_tx_sync_epilog(flags, depend_tx, cb_fn, cb_param);
	}

	return tx;
}

async_tx_find_channel() returns a capable channel from its pool.  The
channel pool is organized as a per-cpu array of channel pointers.  The
async_tx_rebalance() routine is tasked with managing these arrays.  In the
uniprocessor case async_tx_rebalance() tries to spread responsibility
evenly over channels of similar capabilities.  For example if there are two
copy+xor channels, one will handle copy operations and the other will
handle xor.  In the SMP case async_tx_rebalance() attempts to spread the
operations evenly over the cpus, e.g. cpu0 gets copy channel0 and xor
channel0 while cpu1 gets copy channel 1 and xor channel 1.  When a
dependency is specified async_tx_find_channel defaults to keeping the
operation on the same channel.  A xor->copy->xor chain will stay on one
channel if it supports both operation types, otherwise the transaction will
transition between a copy and a xor resource.

Currently the raid5 implementation in the MD raid456 driver has been
converted to the async_tx api.  A driver for the offload engines on the
Intel Xscale series of I/O processors, iop-adma, is provided in a later
commit.  With the iop-adma driver and async_tx, raid456 is able to offload
copy, xor, and xor-zero-sum operations to hardware engines.
 
On iop342 tiobench showed higher throughput for sequential writes (20 - 30%
improvement) and sequential reads to a degraded array (40 - 55%
improvement).  For the other cases performance was roughly equal, +/- a few
percentage points.  On a x86-smp platform the performance of the async_tx
implementation (in synchronous mode) was also +/- a few percentage points
of the original implementation.  According to 'top' on iop342 CPU
utilization drops from ~50% to ~15% during a 'resync' while the speed
according to /proc/mdstat doubles from ~25 MB/s to ~50 MB/s.
 
The tiobench command line used for testing was: tiobench --size 2048
--block 4096 --block 131072 --dir /mnt/raid --numruns 5
* iop342 had 1GB of memory available

Details:
* if CONFIG_DMA_ENGINE=n the asynchronous path is compiled away by making
  async_tx_find_channel a static inline routine that always returns NULL
* when a callback is specified for a given transaction an interrupt will
  fire at operation completion time and the callback will occur in a
  tasklet.  if the the channel does not support interrupts then a live
  polling wait will be performed
* the api is written as a dmaengine client that requests all available
  channels
* In support of dependencies the api implicitly schedules channel-switch
  interrupts.  The interrupt triggers the cleanup tasklet which causes
  pending operations to be scheduled on the next channel
* Xor engines treat an xor destination address differently than a software
  xor routine.  To the software routine the destination address is an implied
  source, whereas engines treat it as a write-only destination.  This patch
  modifies the xor_blocks routine to take a an explicit destination address
  to mirror the hardware.

Changelog:
* fixed a leftover debug print
* don't allow callbacks in async_interrupt_cond
* fixed xor_block changes
* fixed usage of ASYNC_TX_XOR_DROP_DEST
* drop dma mapping methods, suggested by Chris Leech
* printk warning fixups from Andrew Morton
* don't use inline in C files, Adrian Bunk
* select the API when MD is enabled
* BUG_ON xor source counts <= 1
* implicitly handle hardware concerns like channel switching and
  interrupts, Neil Brown
* remove the per operation type list, and distribute operation capabilities
  evenly amongst the available channels
* simplify async_tx_find_channel to optimize the fast path
* introduce the channel_table_initialized flag to prevent early calls to
  the api
* reorganize the code to mimic crypto
* include mm.h as not all archs include it in dma-mapping.h
* make the Kconfig options non-user visible, Adrian Bunk
* move async_tx under crypto since it is meant as 'core' functionality, and
  the two may share algorithms in the future
* move large inline functions into c files
* checkpatch.pl fixes
* gpl v2 only correction

Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-By: NeilBrown <neilb@suse.de>
2007-07-13 08:06:14 -07:00
Dan Williams
685784aaf3 xor: make 'xor_blocks' a library routine for use with async_tx
The async_tx api tries to use a dma engine for an operation, but will fall
back to an optimized software routine otherwise.  Xor support is
implemented using the raid5 xor routines.  For organizational purposes this
routine is moved to a common area.

The following fixes are also made:
* rename xor_block => xor_blocks, suggested by Adrian Bunk
* ensure that xor.o initializes before md.o in the built-in case
* checkpatch.pl fixes
* mark calibrate_xor_blocks __init, Adrian Bunk

Cc: Adrian Bunk <bunk@stusta.de>
Cc: NeilBrown <neilb@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2007-07-13 08:06:14 -07:00
Herbert Xu
124b53d020 [CRYPTO] cryptd: Add software async crypto daemon
This patch adds the cryptd module which is a template that takes a
synchronous software crypto algorithm and converts it to an asynchronous
one by executing it in a kernel thread.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-05-02 14:38:32 +10:00
Herbert Xu
b5b7f08869 [CRYPTO] api: Add async blkcipher type
This patch adds the mid-level interface for asynchronous block ciphers.
It also includes a generic queueing mechanism that can be used by other
asynchronous crypto operations in future.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-05-02 14:38:31 +10:00
Noriaki TAKAMIYA
d64beac050 [CRYPTO] camellia: added the code of Camellia cipher algorithm.
This patch adds the main code of Camellia cipher algorithm.

Signed-off-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-02-07 09:21:03 +11:00
David Howells
90831639a6 [CRYPTO] fcrypt: Add FCrypt from RxRPC
Add a crypto module to provide FCrypt encryption as used by RxRPC.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-02-07 09:20:59 +11:00
David Howells
91652be5d1 [CRYPTO] pcbc: Add Propagated CBC template
Add PCBC crypto template support as used by RxRPC.

Signed-Off-By: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-02-07 09:20:59 +11:00