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>
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>
As Andrew Morton correctly points out, we need to explicitly include
sched.h as we use the function cond_resched in crypto/scatterwalk.h.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
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>
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>
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>
This patch finally makes the givencrypt/givdecrypt operations available
to users by adding crypto_aead_givencrypt and crypto_aead_givdecrypt.
A suite of helpers to allocate and fill in the request is also available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the underlying givcrypt operations for aead and associated
support elements. The rationale is identical to that of the skcipher
givcrypt operations, i.e., sometimes only the algorithm knows how the
IV should be generated.
A new request type aead_givcrypt_request is added which contains an
embedded aead_request structure with two new elements to support this
operation. The new elements are seq and giv. The seq field should
contain a strictly increasing 64-bit integer which may be used by
certain IV generators as an input value. The giv field will be used
to store the generated IV. It does not need to obey the alignment
requirements of the algorithm because it's not used during the operation.
The existing iv field must still be available as it will be used to store
intermediate IVs and the output IV if chaining is desired.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch finally makes the givencrypt/givdecrypt operations available
to users by adding crypto_skcipher_givencrypt and crypto_skcipher_givdecrypt.
A suite of helpers to allocate and fill in the request is also available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that gcm and authenc have been converted to crypto_spawn_skcipher,
this patch removes the obsolete crypto_spawn_ablkcipher function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
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>
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>
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>
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>
As discussed previously, this patch moves the basic CTR functionality
into a chainable algorithm called ctr. The IPsec-specific variant of
it is now placed on top with the name rfc3686.
So ctr(aes) gives a chainable cipher with IV size 16 while the IPsec
variant will be called rfc3686(ctr(aes)). This patch also adjusts
gcm accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a new helper crypto_attr_alg_name which is basically the
first half of crypto_attr_alg. That is, it returns an algorithm name
parameter as a string without looking it up. The caller can then look it
up immediately or defer it until later.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Unfortunately the generic chaining hasn't been ported to all architectures
yet, and notably not s390. So this patch restores the chainging that we've
been using previously which does work everywhere.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The scatterwalk infrastructure is used by algorithms so it needs to
move out of crypto for future users that may live in drivers/crypto
or asm/*/crypto.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Having enckeylen as a template parameter makes it a pain for hardware
devices that implement ciphers with many key sizes since each one would
have to be registered separately.
Since the authenc algorithm is mainly used for legacy purposes where its
key is going to be constructed out of two separate keys, we can in fact
embed this value into the key itself.
This patch does this by prepending an rtnetlink header to the key that
contains the encryption key length.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With the addition of more stream ciphers we need to curb the proliferation
of ad-hoc xor functions. This patch creates a generic pair of functions,
crypto_inc and crypto_xor which does big-endian increment and exclusive or,
respectively.
For optimum performance, they both use u32 operations so alignment must be
as that of u32 even though the arguments are of type u8 *.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Up until now we have ablkcipher algorithms have been identified as
type BLKCIPHER with the ASYNC bit set. This is suboptimal because
ablkcipher refers to two things. On the one hand it refers to the
top-level ablkcipher interface with requests. On the other hand it
refers to and algorithm type underneath.
As it is you cannot request a synchronous block cipher algorithm
with the ablkcipher interface on top. This is a problem because
we want to be able to eventually phase out the blkcipher top-level
interface.
This patch fixes this by making ABLKCIPHER its own type, just as
we have distinct types for HASH and DIGEST. The type it associated
with the algorithm implementation only.
Which top-level interface is used for synchronous block ciphers is
then determined by the mask that's used. If it's a specific mask
then the old blkcipher interface is given, otherwise we go with the
new ablkcipher interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Resubmitting this patch which extends sha256_generic.c to support SHA-224 as
described in FIPS 180-2 and RFC 3874. HMAC-SHA-224 as described in RFC4231
is then supported through the hmac interface.
Patch includes test vectors for SHA-224 and HMAC-SHA-224.
SHA-224 chould be chosen as a hash algorithm when 112 bits of security
strength is required.
Patch generated against the 2.6.24-rc1 kernel and tested against
2.6.24-rc1-git14 which includes fix for scatter gather implementation for HMAC.
Signed-off-by: Jonathan Lynch <jonathan.lynch@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
