Commit graph

19 commits

Author SHA1 Message Date
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
Herbert Xu
5f7082ed4f crypto: hash - Export shash through hash
This patch allows shash algorithms to be used through the old hash
interface.  This is a transitional measure so we can convert the
underlying algorithms to shash before converting the users across.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25 11:01:33 +11:00
Herbert Xu
dec8b78606 crypto: hash - Add import/export interface
It is often useful to save the partial state of a hash function
so that it can be used as a base for two or more computations.

The most prominent example is HMAC where all hashes start from
a base determined by the key.  Having an import/export interface
means that we only have to compute that base once rather than
for each message.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-12-25 11:01:30 +11:00
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
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
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
18e33e6d5c crypto: hash - Move ahash functions into crypto/hash.h
All new crypto interfaces should go into individual files as much
as possible in order to ensure that crypto.h does not collapse under
its own weight.

This patch moves the ahash code into crypto/hash.h and crypto/internal/hash.h
respectively.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:18 +08:00
Herbert Xu
20036252fc crypto: hash - Added scatter list walking helper
This patch adds the walking helpers for hash algorithms akin to
those of block ciphers.  This is a necessary step before we can
reimplement existing hash algorithms using the new ahash interface.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-07-10 20:35:18 +08:00
Herbert Xu
f13ba2f7d3 [CRYPTO] skcipher: Fix section mismatches
The previous patch to move chainiv and eseqiv into blkcipher created
a section mismatch for the chainiv exit function which was also called
from __init.  This patch removes the __exit marking on it.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-03-08 20:29:43 +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
Herbert Xu
e7cd2514ea [CRYPTO] chainiv: Avoid lock spinning where possible
This patch makes chainiv avoid spinning by postponing requests on lock
contention if the user allows the use of asynchronous algorithms.  If
a synchronous algorithm is requested then we behave as before.

This should improve IPsec performance on SMP when two CPUs attempt to
transmit over the same SA.  Currently one of them will spin doing nothing
waiting for the other CPU to finish its encryption.  This patch makes it
postpone the request and get on with other work.

If only one CPU is transmitting for a given SA, then we will process
the request synchronously as before.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:55 +11:00
Herbert Xu
3631c650c4 [CRYPTO] null: Add null blkcipher algorithm
This patch adds a null blkcipher algorithm called ecb(cipher_null) for
backwards compatibility.  Previously the null algorithm when used by
IPsec copied the data byte by byte.  This new algorithm optimises that
to a straight memcpy which lets us better measure inherent overheads in
our IPsec code.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:53 +11:00
Herbert Xu
d29ce988ae [CRYPTO] aead: Create default givcipher instances
This patch makes crypto_alloc_aead always return algorithms that is
capable of generating their own IVs through givencrypt and givdecrypt.
All existing AEAD algorithms already do.  New ones must either supply
their own or specify a generic IV generator with the geniv field.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:52 +11:00
Herbert Xu
5b6d2d7fdf [CRYPTO] aead: Add aead_geniv_alloc/aead_geniv_free
This patch creates the infrastructure to help the construction of IV
generator templates that wrap around AEAD algorithms by adding an IV
generator to them.  This is useful for AEAD algorithms with no built-in
IV generator or to replace their built-in generator.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:51 +11:00
Herbert Xu
b9c55aa475 [CRYPTO] skcipher: Create default givcipher instances
This patch makes crypto_alloc_ablkcipher/crypto_grab_skcipher always
return algorithms that are capable of generating their own IVs through
givencrypt and givdecrypt.  Each algorithm may specify its default IV
generator through the geniv field.

For algorithms that do not set the geniv field, the blkcipher layer will
pick a default.  Currently it's chainiv for synchronous algorithms and
eseqiv for asynchronous algorithms.  Note that if these wrappers do not
work on an algorithm then that algorithm must specify its own geniv or
it can't be used at all.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:46 +11:00
Herbert Xu
15c6728668 [CRYPTO] skcipher: Added skcipher_givcrypt_complete
This patch adds the helper skcipher_givcrypt_complete which should be
called when an ablkcipher algorithm has completed a givcrypt request.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:45 +11:00
Herbert Xu
ecfc43292f [CRYPTO] skcipher: Add skcipher_geniv_alloc/skcipher_geniv_free
This patch creates the infrastructure to help the construction of givcipher
templates that wrap around existing blkcipher/ablkcipher algorithms by adding
an IV generator to them.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:44 +11:00
Herbert Xu
61da88e2b8 [CRYPTO] skcipher: Add givcrypt operations and givcipher type
Different block cipher modes have different requirements for intialisation
vectors.  For example, CBC can use a simple randomly generated IV while
modes such as CTR must use an IV generation mechanisms that give a stronger
guarantee on the lack of collisions.  Furthermore, disk encryption modes
have their own IV generation algorithms.

Up until now IV generation has been left to the users of the symmetric
key cipher API.  This is inconvenient as the number of block cipher modes
increase because the user needs to be aware of which mode is supposed to
be paired with which IV generation algorithm.

Therefore it makes sense to integrate the IV generation into the crypto
API.  This patch takes the first step in that direction by creating two
new ablkcipher operations, givencrypt and givdecrypt that generates an
IV before performing the actual encryption or decryption.

The operations are currently not exposed to the user.  That will be done
once the underlying functionality has actually been implemented.

It also creates the underlying givcipher type.  Algorithms that directly
generate IVs would use it instead of ablkcipher.  All other algorithms
(including all existing ones) would generate a givcipher algorithm upon
registration.  This givcipher algorithm will be constructed from the geniv
string that's stored in every algorithm.  That string will locate a template
which is instantiated by the blkcipher/ablkcipher algorithm in question to
give a givcipher algorithm.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:43 +11:00
Herbert Xu
378f4f51f9 [CRYPTO] skcipher: Add crypto_grab_skcipher interface
Note: From now on the collective of ablkcipher/blkcipher/givcipher will
be known as skcipher, i.e., symmetric key cipher.  The name blkcipher has
always been much of a misnomer since it supports stream ciphers too.

This patch adds the function crypto_grab_skcipher as a new way of getting
an ablkcipher spawn.  The problem is that previously we did this in two
steps, first getting the algorithm and then calling crypto_init_spawn.

This meant that each spawn user had to be aware of what type and mask to
use for these two steps.  This is difficult and also presents a problem
when the type/mask changes as they're about to be for IV generators.

The new interface does both steps together just like crypto_alloc_ablkcipher.

As a side-effect this also allows us to be stronger on type enforcement
for spawns.  For now this is only done for ablkcipher but it's trivial
to extend for other types.

This patch also moves the type/mask logic for skcipher into the helpers
crypto_skcipher_type and crypto_skcipher_mask.

Finally this patch introduces the function crypto_require_sync to determine
whether the user is specifically requesting a sync algorithm.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11 08:16:42 +11:00