This patch adds the crypto_type structure which will be used for all new
crypto algorithm types, beginning with block ciphers.
The primary purpose of this abstraction is to allow different crypto_type
objects for crypto algorithms of the same type, in particular, there will
be a different crypto_type objects for asynchronous algorithms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Up until now all crypto transforms have been of the same type, struct
crypto_tfm, regardless of whether they are ciphers, digests, or other
types. As a result of that, we check the types at run-time before
each crypto operation.
This is rather cumbersome. We could instead use different C types for
each crypto type to ensure that the correct types are used at compile
time. That is, we would have crypto_cipher/crypto_digest instead of
just crypto_tfm. The appropriate type would then be required for the
actual operations such as crypto_digest_digest.
Now that we have the type/mask fields when looking up algorithms, it
is easy to request for an algorithm of the precise type that the user
wants. However, crypto_alloc_tfm currently does not expose these new
attributes.
This patch introduces the function crypto_alloc_base which will carry
these new parameters. It will be renamed to crypto_alloc_tfm once
all existing users have been converted.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the asynchronous flag and changes all existing users to
only look up algorithms that are synchronous.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Spawns lock a specific crypto algorithm in place. They can then be used
with crypto_spawn_tfm to allocate a tfm for that algorithm. When the base
algorithm of a spawn is deregistered, all its spawns will be automatically
removed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch also adds the infrastructure to pick an algorithm based on
their type. For example, this allows you to select the encryption
algorithm "aes", instead of any algorithm registered under the name
"aes". For now this is only accessible internally. Eventually it
will be made available through crypto_alloc_tfm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The cryptomgr module is a simple manager of crypto algorithm instances.
It ensures that parameterised algorithms of the type tmpl(alg) (e.g.,
cbc(aes)) are always created.
This is meant to satisfy the needs for most users. For more complex
cases such as deeper combinations or multiple parameters, a netlink
module will be created which allows arbitrary expressions to be parsed
in user-space.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a notifier chain for algorithm/template registration events.
This will be used to register compound algorithms such as cbc(aes). In
future this will also be passed onto user-space through netlink.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The crypto API is made up of the part facing users such as IPsec and the
low-level part which is used by cryptographic entities such as algorithms.
This patch splits out the latter so that the two APIs are more clearly
delineated. As a bonus the low-level API can now be modularised if all
algorithms are built as modules.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Up until now we've relied on module reference counting to ensure that the
crypto_alg structures don't disappear from under us. This was good enough
as long as each crypto_alg came from exactly one module.
However, with parameterised crypto algorithms a crypto_alg object may need
two or more modules to operate. This means that we need to count the
references to the crypto_alg object directly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The functions crypto_alg_get and crypto_alg_put operates on the crypto
modules rather than the algorithms. Therefore it makes sense to call
them crypto_mod_get and crypto_alg_put respectively.
This is needed because we need to have real algorithm reference counters
for parameterised algorithms as they can be unregistered from below by
when their parameter algorithms are themselves unregistered.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
We already allow asynchronous removal of existing algorithm modules. By
allowing the replacement of existing algorithms, we can replace algorithms
without having to wait for for all existing users to complete.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We do need to change these names now and even more so in future with
instantiated algorithms. So let's stop lying to the compiler and get
rid of the const modifiers.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the hooks cra_init/cra_exit which are called during a tfm's
construction and destruction respectively. This will be used by the instances
to allocate child tfm's.
For now this lets us get rid of the coa_init/coa_exit functions which are
used for exactly that purpose (unlike the dia_init function which is called
for each transaction).
In fact the coa_exit path is currently buggy as it may get called twice
when an error is encountered during initialisation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
this patch converts crypto/ to kzalloc usage.
Compile tested with allyesconfig.
Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since tfm contexts can contain arbitrary types we should provide at least
natural alignment (__attribute__ ((__aligned__))) for them. In particular,
this is needed on the Xscale which is a 32-bit architecture with a u64 type
that requires 64-bit alignment. This problem was reported by Ronen Shitrit.
The crypto_tfm structure's size was 44 bytes on 32-bit architectures and
80 bytes on 64-bit architectures. So adding this requirement only means
that we have to add an extra 4 bytes on 32-bit architectures.
On i386 the natural alignment is 16 bytes which also benefits the VIA
Padlock as it no longer has to manually align its context structure to
128 bits.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The cipher code path may allocate up to two blocks of data on the stack.
Therefore we need to place limits on the maximum block size.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is the first step on the road towards asynchronous support in
the Crypto API. It adds support for having multiple crypto_alg objects
for the same algorithm registered in the system.
For example, each device driver would register a crypto_alg object
for each algorithm that it supports. While at the same time the
user may load software implementations of those same algorithms.
Users of the Crypto API may then select a specific implementation
by name, or choose any implementation for a given algorithm with
the highest priority.
The priority field is a 32-bit signed integer. In future it will be
possible to modify it from user-space.
This also provides a solution to the problem of selecting amongst
various AES implementations, that is, aes vs. aes-i586 vs. aes-padlock.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The cipher code relies on the fact that the block size is a multiple
of the required alignment. So we should check this at the time of
algorith registration. We also ensure that the block size is bounded
by the page size.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The crypto layer currently uses in_atomic() to determine whether it is
allowed to sleep. This is incorrect since spin locks don't always cause
in_atomic() to return true.
Instead of that, this patch returns to an earlier idea of a per-tfm flag
which determines whether sleeping is allowed. Unlike the earlier version,
the default is to not allow sleeping. This ensures that no existing code
can break.
As usual, this flag may either be set through crypto_alloc_tfm(), or
just before a specific crypto operation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
As far as I'm aware there's a general concensus that functions that are
responsible for freeing resources should be able to cope with being passed
a NULL pointer. This makes sense as it removes the need for all callers to
check for NULL, thus elliminating the bugs that happen when some forget
(safer to just check centrally in the freeing function) and it also makes
for smaller code all over due to the lack of all those NULL checks.
This patch makes it safe to pass the crypto_free_tfm() function a NULL
pointer. Once this patch is applied we can start removing the NULL checks
from the callers.
Signed-off-by: Jesper Juhl <juhl-lkml@dif.dk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch ensures that cit_iv is aligned according to cra_alignmask
by allocating it as part of the tfm structure. As a side effect the
crypto layer will also guarantee that the tfm ctx area has enough space
to be aligned by cra_alignmask. This allows us to remove the extra
space reservation from the Padlock driver.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch makes a needlessly global function static.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
The VIA Padlock device requires the input and output buffers to
be aligned on 16-byte boundaries. This patch adds the alignmask
attribute for low-level cipher implementations to indicate their
alignment requirements.
The mid-level crypt() function will copy the input/output buffers
if they are not aligned correctly before they are passed to the
low-level implementation.
Strictly speaking, some of the software implementations require
the buffers to be aligned on 4-byte boundaries as they do 32-bit
loads. However, it is not clear whether it is better to copy
the buffers or pay the penalty for unaligned loads/stores.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
