This patch makes /proc/crypto call the type-specific show function
if one is present before calling the legacy show functions for
cipher/digest/compress. This allows us to reuse the type values
for those legacy types. In particular, hash and digest will share
one type value while shash is phased in as the default hash type.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch allows shash algorithms to be used through the ahash
interface. This is required before we can convert digest algorithms
over to shash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch reintroduces a completely revamped crypto_alloc_tfm.
The biggest change is that we now take two crypto_type objects
when allocating a tfm, a frontend and a backend. In fact this
simply formalises what we've been doing behind the API's back.
For example, as it stands crypto_alloc_ahash may use an
actual ahash algorithm or a crypto_hash algorithm. Putting
this in the API allows us to do this much more cleanly.
The existing types will be converted across gradually.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The type exit function needs to undo any allocations done by the type
init function. However, the type init function may differ depending
on the upper-level type of the transform (e.g., a crypto_blkcipher
instantiated as a crypto_ablkcipher).
So we need to move the exit function out of the lower-level
structure and into crypto_tfm itself.
As it stands this is a no-op since nobody uses exit functions at
all. However, all cases where a lower-level type is instantiated
as a different upper-level type (such as blkcipher as ablkcipher)
will be converted such that they allocate the underlying transform
and use that instead of casting (e.g., crypto_ablkcipher casted
into crypto_blkcipher). That will need to use a different exit
function depending on the upper-level type.
This patch also allows the type init/exit functions to call (or not)
cra_init/cra_exit instead of always calling them from the top level.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a patch that was sent to me by Jarod Wilson, marking off my
outstanding todo to allow the ansi cprng to set/reset the DT counter value in a
cprng instance. Currently crytpo_rng_reset accepts a seed byte array which is
interpreted by the ansi_cprng as a {V key} tuple. This patch extends that tuple
to now be {V key DT}, with DT an optional value during reset. This patch also
fixes a bug we noticed in which the offset of the key area of the seed is
started at DEFAULT_PRNG_KSZ rather than DEFAULT_BLK_SZ as it should be.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Jarod Wilson <jarod@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove the private implementation of 32-bit rotation and unaligned
access with byteswapping.
As a bonus, fixes sparse warnings:
crypto/camellia.c:602:2: warning: cast to restricted __be32
crypto/camellia.c:603:2: warning: cast to restricted __be32
crypto/camellia.c:604:2: warning: cast to restricted __be32
crypto/camellia.c:605:2: warning: cast to restricted __be32
crypto/camellia.c:710:2: warning: cast to restricted __be32
crypto/camellia.c:711:2: warning: cast to restricted __be32
crypto/camellia.c:712:2: warning: cast to restricted __be32
crypto/camellia.c:713:2: warning: cast to restricted __be32
crypto/camellia.c:714:2: warning: cast to restricted __be32
crypto/camellia.c:715:2: warning: cast to restricted __be32
crypto/camellia.c:716:2: warning: cast to restricted __be32
crypto/camellia.c:717:2: warning: cast to restricted __be32
[Thanks to Tomoyuki Okazaki for spotting the typo]
Tested-by: Carlo E. Prelz <fluido@fluido.as>
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The FIPS specification requires that should self test for any supported
crypto algorithm fail during operation in fips mode, we need to prevent
the use of any crypto functionality until such time as the system can
be re-initialized. Seems like the best way to handle that would be
to panic the system if we were in fips mode and failed a self test.
This patch implements that functionality. I've built and run it
successfully.
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
Mapping the destination multiple times is a misuse of the dma-api.
Since the destination may be reused as a source, ensure that it is only
mapped once and that it is mapped bidirectionally. This appears to add
ugliness on the unmap side in that it always reads back the destination
address from the descriptor, but gcc can determine that dma_unmap is a
nop and not emit the code that calculates its arguments.
Cc: <stable@kernel.org>
Cc: Saeed Bishara <saeed@marvell.com>
Acked-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
fsldma: allow Freescale Elo DMA driver to be compiled as a module
fsldma: remove internal self-test from Freescale Elo DMA driver
drivers/dma/dmatest.c: switch a GFP_ATOMIC to GFP_KERNEL
dmatest: properly handle duplicate DMA channels
drivers/dma/ioat_dma.c: drop code after return
async_tx: make async_tx_run_dependencies() easier to read
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: skcipher - Use RNG interface instead of get_random_bytes
crypto: rng - RNG interface and implementation
crypto: api - Add fips_enable flag
crypto: skcipher - Move IV generators into their own modules
crypto: cryptomgr - Test ciphers using ECB
crypto: api - Use test infrastructure
crypto: cryptomgr - Add test infrastructure
crypto: tcrypt - Add alg_test interface
crypto: tcrypt - Abort and only log if there is an error
crypto: crc32c - Use Intel CRC32 instruction
crypto: tcrypt - Avoid using contiguous pages
crypto: api - Display larval objects properly
crypto: api - Export crypto_alg_lookup instead of __crypto_alg_lookup
crypto: Kconfig - Replace leading spaces with tabs
* Rename 'next' to 'dep'
* Move the channel switch check inside the loop to simplify
termination
Acked-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This reverts commit bd699f2df6,
which causes camellia to fail the included self-test vectors.
It has also been confirmed that it breaks existing encrypted
disks using camellia.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Should clear the next pointer of the TX if we are sure that the
next TX (say NXT) will be submitted to the channel too. Overwise,
we break the chain of descriptors, because we lose the information
about the next descriptor to run. So next time, when invoke
async_tx_run_dependencies() with TX, it's TX->next will be NULL, and
NXT will be never submitted.
Cc: <stable@kernel.org> [2.6.26]
Signed-off-by: Yuri Tikhonov <yur@emcraft.com>
Signed-off-by: Ilya Yanok <yanok@emcraft.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
This patch makes the IV generators use the new RNG interface so
that the user can pick an RNG other than the default get_random_bytes.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
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>
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>
As it is we only test ciphers when combined with a mode. That means
users that do not invoke a mode of operations may get an untested
cipher.
This patch tests all ciphers using the ECB mode so that simple cipher
users such as ansi-cprng are also protected.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes use of the new testing infrastructure by requiring
algorithms to pass a run-time test before they're made available to
users.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch creates a new interface algorithm testing. A test can
be requested for a particular implementation of an algorithm. This
is achieved by taking both the name of the algorithm and that of
the implementation.
The all-inclusive test has also been rewritten to no longer require
a duplicate listing of all algorithms with tests. In that process
a number of missing tests have also been discovered and rectified.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The info printed is a complete waste of space when there is no error
since it doesn't tell us anything that we don't already know. If there
is an error, we can also be more verbose.
In case that there is an error, this patch also aborts the test and
returns the error to the caller. In future this will be used to
algorithms at registration time.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
From NHM processor onward, Intel processors can support hardware accelerated
CRC32c algorithm with the new CRC32 instruction in SSE 4.2 instruction set.
The patch detects the availability of the feature, and chooses the most proper
way to calculate CRC32c checksum.
Byte code instructions are used for compiler compatibility.
No MMX / XMM registers is involved in the implementation.
Signed-off-by: Austin Zhang <austin.zhang@intel.com>
Signed-off-by: Kent Liu <kent.liu@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If tcrypt is to be used as a run-time integrity test, it needs to be
more resilient in a hostile environment. For a start allocating 32K
of physically contiguous memory is definitely out.
This patch teaches it to use separate pages instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rather than displaying larval objects as real objects, this patch
makes them show up under /proc/crypto as of type larval.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since the only user of __crypto_alg_lookup is doing exactly what
crypto_alg_lookup does, we can now the latter in lieu of the former.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Authenc works in two stages for encryption, it first encrypts and
then computes an ICV. The context memory of the request is used
by both operations. The problem is that when an asynchronous
encryption completes, we will compute the ICV and then reread the
context memory of the encryption to get the original request.
It just happens that we have a buffer of 16 bytes in front of the
request pointer, so ICVs of 16 bytes (such as SHA1) do not trigger
the bug. However, any attempt to uses a larger ICV instantly kills
the machine when the first asynchronous encryption is completed.
This patch fixes this by saving the request pointer before we start
the ICV computation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The changeset ca786dc738
crypto: hash - Fixed digest size check
missed one spot for the digest type. This patch corrects that
error.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
My changeset 4b22f0ddb6
crypto: tcrpyt - Remove unnecessary kmap/kunmap calls
introduced a typo that broke AEAD chunk testing. In particular,
axbuf should really be xbuf.
There is also an issue with testing the last segment when encrypting.
The additional part produced by AEAD wasn't tested. Similarly, on
decryption the additional part of the AEAD input is mistaken for
corruption.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (24 commits)
I/OAT: I/OAT version 3.0 support
I/OAT: tcp_dma_copybreak default value dependent on I/OAT version
I/OAT: Add watchdog/reset functionality to ioatdma
iop_adma: cleanup iop_chan_xor_slot_count
iop_adma: document how to calculate the minimum descriptor pool size
iop_adma: directly reclaim descriptors on allocation failure
async_tx: make async_tx_test_ack a boolean routine
async_tx: remove depend_tx from async_tx_sync_epilog
async_tx: export async_tx_quiesce
async_tx: fix handling of the "out of descriptor" condition in async_xor
async_tx: ensure the xor destination buffer remains dma-mapped
async_tx: list_for_each_entry_rcu() cleanup
dmaengine: Driver for the Synopsys DesignWare DMA controller
dmaengine: Add slave DMA interface
dmaengine: add DMA_COMPL_SKIP_{SRC,DEST}_UNMAP flags to control dma unmap
dmaengine: Add dma_client parameter to device_alloc_chan_resources
dmatest: Simple DMA memcpy test client
dmaengine: DMA engine driver for Marvell XOR engine
iop-adma: fix platform driver hotplug/coldplug
dmaengine: track the number of clients using a channel
...
Fixed up conflict in drivers/dca/dca-sysfs.c manually
All callers of async_tx_sync_epilog have called async_tx_quiesce on the
depend_tx, so async_tx_sync_epilog need only call the callback to
complete the operation.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Ensure forward progress is made when a dmaengine driver is unable to
allocate an xor descriptor by breaking the dependency chain with
async_tx_quisce() and issue any pending descriptors.
Tested with iop-adma by setting device->max_xor = 2 to force multiple
calls to device_prep_dma_xor for each call to async_xor and limiting the
descriptor slot pool to 5. Discovered that the minimum descriptor pool
size for iop-adma is 2 * iop_chan_xor_slot_cnt(device->max_xor) + 1.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
When the number of source buffers for an xor operation exceeds the hardware
channel maximum async_xor creates a chain of dependent operations. The result
of one operation is reused as an input to the next to continue the xor
calculation. The destination buffer should remain mapped for the duration of
the entire chain. To provide this guarantee the code must no longer be allowed
to fallback to the synchronous path as this will preclude the buffer from being
unmapped, i.e. the dma-driver will potentially miss the descriptor with
!DMA_COMPL_SKIP_DEST_UNMAP.
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
In the rcu update side, don't use list_for_each_entry_rcu().
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
This patch reimplements crc32c using the ahash interface. This
allows one tfm to be used by an unlimited number of users provided
that they all use the same key (which all current crc32c users do).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
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>
The base field in ahash_tfm appears to have been cut-n-pasted from
ablkcipher. It isn't needed here at all. Similarly, the info field
in ahash_request also appears to have originated from its cipher
counter-part and is vestigial.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The digest size check on hash algorithms is incorrect. It's
perfectly valid for hash algorithms to have a digest length
longer than their block size. For example crc32c has a block
size of 1 and a digest size of 4. Rather than having it lie
about its block size, this patch fixes the checks to do what
they really should which is to bound the digest size so that
code placing the digest on the stack continue to work.
HMAC however still needs to check this as it's only defined
for such algorithms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Similar to the rmd128.c annotations, significantly cuts down on the
noise.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove the private implementation of 32-bit rotation and unaligned
access with byteswapping.
As a bonus, fixes sparse warnings:
crypto/camellia.c:602:2: warning: cast to restricted __be32
crypto/camellia.c:603:2: warning: cast to restricted __be32
crypto/camellia.c:604:2: warning: cast to restricted __be32
crypto/camellia.c:605:2: warning: cast to restricted __be32
crypto/camellia.c:710:2: warning: cast to restricted __be32
crypto/camellia.c:711:2: warning: cast to restricted __be32
crypto/camellia.c:712:2: warning: cast to restricted __be32
crypto/camellia.c:713:2: warning: cast to restricted __be32
crypto/camellia.c:714:2: warning: cast to restricted __be32
crypto/camellia.c:715:2: warning: cast to restricted __be32
crypto/camellia.c:716:2: warning: cast to restricted __be32
crypto/camellia.c:717:2: warning: cast to restricted __be32
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Noticed by Neil Horman: we are doing unnecessary kmap/kunmap calls
on kmalloced memory. This patch removes them. For the purposes of
testing SG construction, the underlying crypto code already does plenty
of kmap/kunmap calls anyway.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Patch to add checking of DES3 test vectors using CBC mode. FIPS-140-2
compliance mandates that any supported mode of operation must include a self
test. This satisfies that requirement for cbc(des3_ede). The included test
vector was generated by me using openssl. Key/IV was generated with the
following command:
openssl enc -des_ede_cbc -P
input and output values were generated by repeating the string "Too many
secrets" a few times over, truncating it to 128 bytes, and encrypting it with
openssl using the aformentioned key. Tested successfully by myself
Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch converts the relevant code in the rmd implementations to
use the pointer form of the endian swapping operations. This allows
certain architectures to generate more optimised code. For example,
on sparc64 this more than halves the CPU cycles on a typical hashing
operation.
Based on a patch by David Miller.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes endian issues making rmd320 work
properly on big-endian machines.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Acked-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes endian issues making rmd256 work
properly on big-endian machines.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Acked-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes endian issues making rmd160 work
properly on big-endian machines.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Acked-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch is based on Sebastian Siewior's patch and
fixes endian issues making rmd128 work properly on
big-endian machines.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Acked-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch changes tcrypt to use the new asynchronous hash interface
for testing hash algorithm correctness. The speed tests will continue
to use the existing interface for now.
Signed-off-by: Loc Ho <lho@amcc.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds asynchronous hash support to crypto daemon.
Signed-off-by: Loc Ho <lho@amcc.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds Kconfig entries for 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>
This patch adds test vectors for RIPEMD-256 and
RIPEMD-320 hash algorithms.
The test vectors are taken from
<http://homes.esat.kuleuven.be/~bosselae/ripemd160.html>
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch puts all common RIPEMD values in the
appropriate header file. Initial values and constants
are the same for all variants of RIPEMD.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Check whether the destination buffer is written to beyond the last
byte contained in the scatterlist.
Also change IDX1 of the cross-page access offsets to a multiple of 4.
This triggers a corruption in the HIFN driver and doesn't seem to
negatively impact other testcases.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Change logs should be kept in source control systems, not the source.
This patch removes the change log from tcrpyt to stop people from
extending it any more.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds Kconfig entries for RIPEMD-128 and RIPEMD-160.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds test vectors for RIPEMD-128 and
RIPEMD-160 hash algorithms and digests (HMAC).
The test vectors are taken from ISO:IEC 10118-3 (2004)
and RFC2286.
Signed-off-by: Adrian-Ken Rueegsegger <rueegsegger@swiss-it.ch>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
The EINPROGRESS notifications should be done just like the final
call-backs, i.e., with BH off. This patch fixes the call in cryptd
since previously it was called with BH on.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When chainiv postpones requests it never calls their completion functions.
This causes symptoms such as memory leaks when IPsec is in use.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
commit 636bdeaa 'dmaengine: ack to flags: make use of the unused bits in
the 'ack' field' missed an ->ack conversion in
crypto/async_tx/async_memset.c
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Coverity CID: 2306 & 2307 RESOURCE_LEAK
In the second for loop in test_cipher(), data is allocated space with
kzalloc() and is only ever freed in an error case.
Looking at this loop, data is written to this memory but nothing seems
to read from it.
So here is a patch removing the allocation, I think this is the right
fix.
Only compile tested.
Signed-off-by: Darren Jenkins <darrenrjenkins@gmailcom>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move rcu-protected lists from list.h into a new header file rculist.h.
This is done because list are a very used primitive structure all over the
kernel and it's currently impossible to include other header files in this
list.h without creating some circular dependencies.
For example, list.h implements rcu-protected list and uses rcu_dereference()
without including rcupdate.h. It actually compiles because users of
rcu_dereference() are macros. Others RCU functions could be used too but
aren't probably because of this.
Therefore this patch creates rculist.h which includes rcupdates without to
many changes/troubles.
Signed-off-by: Franck Bui-Huu <fbuihuu@gmail.com>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Josh Triplett <josh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
When HMAC gets a key longer than the block size of the hash, it needs
to feed it as input to the hash to reduce it to a fixed length. As
it is HMAC converts the key to a scatter and gather list. However,
this doesn't work on certain platforms if the key is not allocated
via kmalloc. For example, the keys from tcrypt are stored in the
rodata section and this causes it to fail with HMAC on x86-64.
This patch fixes this by copying the key to memory obtained via
kmalloc before hashing it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Normally, kzalloc returns NULL or a valid pointer value, not a value to be
tested using IS_ERR.
Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
After attaching the IV to the head during encryption, eseqiv does not
increase the encryption length by that amount. As such the last block
of the actual plain text will be left unencrypted.
Fortunately the only user of this code hifn currently crashes so this
shouldn't affect anyone :)
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Ciphers, block modes, name it, are grouped together and sorted.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On Thu, Mar 27, 2008 at 03:40:36PM +0100, Bodo Eggert wrote:
> Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> wrote:
>
> > This patch cleanups the crypto code, replaces the init() and fini()
> > with the <algorithm name>_init/_fini
>
> This part ist OK.
>
> > or init/fini_<algorithm name> (if the
> > <algorithm name>_init/_fini exist)
>
> Having init_foo and foo_init won't be a good thing, will it? I'd start
> confusing them.
>
> What about foo_modinit instead?
Thanks for the suggestion, the init() is replaced with
<algorithm name>_mod_init ()
and fini () is replaced with <algorithm name>_mod_fini.
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The key expansion routine could be get little more generic, become
a kernel doc entry and then get exported.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Tested-by: Stefan Hellermann <stefan@the2masters.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
The third test vector of ECB-XTEA-ENC fails for me all other
are fine. I could not find a RFC or something else where they
are defined. The test vector has not been modified since git
started recording histrory. The implementation is very close
(not to say equal) to what is available as Public Domain (they
recommend 64 rounds and the in kernel uses 32). Therefore I
belive that there is typo somewhere and tcrypt reported always
*fail* instead of *okey*.
This patch replaces input + result of the third test vector with
result + input from the third decryption vector. The key is the
same, the other three test vectors are also the reverse.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently the tcrypt module is about 2 MiB on x86-32. The
main reason for the huge size is the data segment which contains
all the test vectors for each algorithm. The test vectors are
staticly allocated in an array and the size of the array has been
drastically increased by the merge of the Salsa20 test vectors.
With a hint from Benedigt Spranger I found a way how I could
convert those fixed-length arrays to strings which are flexible
in size. VIM and regex were also very helpfull :)
So, I am talking about a shrinking of ~97% on x86-32:
text data bss dec hex filename
18309 2039708 20 2058037 1f6735 tcrypt-b4.ko
45628 23516 80 69224 10e68 tcrypt.ko
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The test routines (test_{cipher,hash,aead}) are makeing a copy
of the test template and are processing the encryption process
in place. This patch changes the creation of the copy so it will
work even if the source address of the input data isn't an array
inside of the template but a pointer.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The speed templates as it look always the same. The key size
is repeated for each block size and we test always the same
block size. The addition of one inner loop makes it possible
to get rid of the struct and it is possible to use a tiny
u8 array :)
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Some crypto ciphers which are impleneted support similar key sizes
(16,24 & 32 byte). They can be grouped together and use a common
templatte instead of their own which contains the same data.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
'ack' is currently a simple integer that flags whether or not a client is done
touching fields in the given descriptor. It is effectively just a single bit
of information. Converting this to a flags parameter allows the other bits to
be put to use to control completion actions, like dma-unmap, and capture
results, like xor-zero-sum == 0.
Changes are one of:
1/ convert all open-coded ->ack manipulations to use async_tx_ack
and async_tx_test_ack.
2/ set the ack bit at prep time where possible
3/ make drivers store the flags at prep time
4/ add flags to the device_prep_dma_interrupt prototype
Acked-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Shrink struct dma_async_tx_descriptor and introduce
async_tx_channel_switch to properly inject a channel switch interrupt in
the descriptor stream. This simplifies the locking model as drivers no
longer need to handle dma_async_tx_descriptor.lock.
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
The kernel crashes when ipsec passes a udp packet of about 14XX bytes
of data to aes-xcbc-mac.
It seems the first xxxx bytes of the data are in first sg entry,
and remaining xx bytes are in next sg entry. But we don't
check next sg entry to see if we need to go look the page up.
I noticed in hmac.c, we do a scatterwalk_sg_next(), to do this check
and possible lookup, thus xcbc.c needs to use this routine too.
A 15-hour run of an ipsec stress test sending streams of tcp and
udp packets of various sizes, using this patch and
aes-xcbc-mac completed successfully, so hopefully this fixes the
problem.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the channel cannot perform the operation in one call to
->device_prep_dma_zero_sum, then fallback to the xor+page_is_zero path.
This only affects users with arrays larger than 16 devices on iop13xx or
32 devices on iop3xx.
Cc: <stable@kernel.org>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
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>
When using aes-xcbc-mac for authentication in IPsec,
the kernel crashes. It seems this algorithm doesn't
account for the space IPsec may make in scatterlist for authtag.
Thus when crypto_xcbc_digest_update2() gets called,
nbytes may be less than sg[i].length.
Since nbytes is an unsigned number, it wraps
at the end of the loop allowing us to go back
into loop and causing crash in memcpy.
I used update function in digest.c to model this fix.
Please let me know if it looks ok.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The XTS blockmode uses a copy of the IV which is saved on the stack
and may or may not be properly aligned. If it is not, it will break
hardware cipher like the geode or padlock.
This patch encrypts the IV in place so we don't have to worry about
alignment.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Tested-by: Stefan Hellermann <stefan@the2masters.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Every file should include the headers containing the externs for its
global code (in this case for struct crypto_{init,exit}_digest_ops()).
Signed-off-by: Adrian Bunk <bunk@kernel.org>
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>
This patch fixes the following build error caused by commit
3631c650c4:
<-- snip -->
...
LD .tmp_vmlinux1
crypto/built-in.o: In function `skcipher_null_crypt':
crypto_null.c:(.text+0x3d14): undefined reference to `blkcipher_walk_virt'
crypto_null.c:(.text+0x3d14): relocation truncated to fit: R_MIPS_26 against `blkcipher_walk_virt'
crypto/built-in.o: In function `$L32':
crypto_null.c:(.text+0x3d54): undefined reference to `blkcipher_walk_done'
crypto_null.c:(.text+0x3d54): relocation truncated to fit: R_MIPS_26 against `blkcipher_walk_done'
crypto/built-in.o:(.data+0x2e8): undefined reference to `crypto_blkcipher_type'
make[1]: *** [.tmp_vmlinux1] Error 1
<-- snip -->
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Building latest git fails with the following error:
ERROR: "crypto_alloc_ablkcipher" [crypto/tcrypt.ko] undefined!
This appears to happen because CONFIG_CRYPTO_TEST is set while
CONFIG_CRYPTO_BLKCIPHER is not.
The following patch fixes the problem for me.
Signed-off-by: Frederik Deweerdt <frederik.deweerdt@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The source and destination addresses are included to allow channel
selection based on address alignment.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Pass a full set of flags to drivers' per-operation 'prep' routines.
Currently the only flag passed is DMA_PREP_INTERRUPT. The expectation is
that arch-specific async_tx_find_channel() implementations can exploit this
capability to find the best channel for an operation.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
The tx_set_src and tx_set_dest methods were originally implemented to allow
an array of addresses to be passed down from async_xor to the dmaengine
driver while minimizing stack overhead. Removing these methods allows
drivers to have all transaction parameters available at 'prep' time, saves
two function pointers in struct dma_async_tx_descriptor, and reduces the
number of indirect branches..
A consequence of moving this data to the 'prep' routine is that
multi-source routines like async_xor need temporary storage to convert an
array of linear addresses into an array of dma addresses. In order to keep
the same stack footprint of the previous implementation the input array is
reused as storage for the dma addresses. This requires that
sizeof(dma_addr_t) be less than or equal to sizeof(void *). As a
consequence CONFIG_DMADEVICES now depends on !CONFIG_HIGHMEM64G. It also
requires that drivers be able to make descriptor resources available when
the 'prep' routine is polled.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Shannon Nelson <shannon.nelson@intel.com>
Remove the unused ASYNC_TX_ASSUME_COHERENT flag. Async_tx is
meant to hide the difference between asynchronous hardware and synchronous
software operations, this flag requires clients to understand cache
coherency consequences of the async path.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
single list_head variable initialized with LIST_HEAD_INIT could almost
always can be replaced with LIST_HEAD declaration, this shrinks the code
and looks better.
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
do_async_xor must be compiled away on !HAS_DMA archs.
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Cornelia Huck <cornelia.huck@de.ibm.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (125 commits)
[CRYPTO] twofish: Merge common glue code
[CRYPTO] hifn_795x: Fixup container_of() usage
[CRYPTO] cast6: inline bloat--
[CRYPTO] api: Set default CRYPTO_MINALIGN to unsigned long long
[CRYPTO] tcrypt: Make xcbc available as a standalone test
[CRYPTO] xcbc: Remove bogus hash/cipher test
[CRYPTO] xcbc: Fix algorithm leak when block size check fails
[CRYPTO] tcrypt: Zero axbuf in the right function
[CRYPTO] padlock: Only reset the key once for each CBC and ECB operation
[CRYPTO] api: Include sched.h for cond_resched in scatterwalk.h
[CRYPTO] salsa20-asm: Remove unnecessary dependency on CRYPTO_SALSA20
[CRYPTO] tcrypt: Add select of AEAD
[CRYPTO] salsa20: Add x86-64 assembly version
[CRYPTO] salsa20_i586: Salsa20 stream cipher algorithm (i586 version)
[CRYPTO] gcm: Introduce rfc4106
[CRYPTO] api: Show async type
[CRYPTO] chainiv: Avoid lock spinning where possible
[CRYPTO] seqiv: Add select AEAD in Kconfig
[CRYPTO] scatterwalk: Handle zero nbytes in scatterwalk_map_and_copy
[CRYPTO] null: Allow setkey on digest_null
...
Currently the gcm(aes) tests have to be taken together with all other
algorithms. This patch makes it available by itself at number 106.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When setting the digest size xcbc tests to see if the underlying algorithm
is a hash. This is silly because we don't allow it to be a hash and we've
specifically requested for a cipher.
This patch removes the bogus test.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When the underlying algorithm has a block size other than 16 we abort
without freeing it. In fact, we try to return the algorithm itself
as an error!
This patch plugs the leak and makes it return -EINVAL instead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The axbuf buffer is used by test_aead and therefore should be zeroed
there instead of in test_hash.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is the x86-64 version of the Salsa20 stream cipher algorithm. The
original assembly code came from
<http://cr.yp.to/snuffle/salsa20/amd64-3/salsa20.s>. It has been
reformatted for clarity.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch contains the salsa20-i586 implementation. The original
assembly code came from
<http://cr.yp.to/snuffle/salsa20/x86-pm/salsa20.s>. I have reformatted
it (added indents) so that it matches the other algorithms in
arch/x86/crypto.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the rfc4106 wrapper for GCM just as we have an
rfc4309 wrapper for CCM. The purpose of the wrapper is to include part
of the IV in the key so that it can be negotiated by IPsec.
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>
Now that seqiv supports AEAD algorithms it needs to select the AEAD option.
Thanks to Erez Zadok for pointing out the problem.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
It's better to return silently than crash and burn when someone feeds us
a zero length. In particular the null digest algorithm when used as part
of authenc will do that to us.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We need to allow setkey on digest_null if it is to be used directly by
authenc instead of through hmac.
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 adds 7 test vectors to tcrypt for CCM.
The test vectors are from rfc 3610.
There are about 10 more test vectors in RFC 3610
and 4 or 5 more in NIST. I can add these as time permits.
I also needed to set authsize. CCM has a prerequisite of
authsize.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
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 adds support for using seqiv with AEAD algorithms. This is
useful for those AEAD algorithms that performs authentication before
encryption because the IV generated by the underlying encryption algorithm
won't be available for authentication.
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>
Some algorithms always require manual IV construction. For instance,
the generic CCM algorithm requires the first byte of the IV to be manually
constructed. Such algorithms are always used by other algorithms equipped
with their own IV generators and do not need IV generation per se.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch implements the givencrypt function for authenc. It simply
calls the givencrypt operation on the underlying cipher instead of encrypt.
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 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>
This patch converts the gcm algorithm over to crypto_grab_skcipher
which is a prerequisite for IV generation.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the gcm_base template which takes a block cipher
parameter instead of cipher. This allows the user to specify a
specific CTR implementation.
This also fixes a leak of the cipher algorithm that was previously
looked up but never freed.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch converts the authenc algorithm over to crypto_grab_skcipher
which is a prerequisite for IV generation.
This patch also changes authenc to set its ASYNC status depending on
the ASYNC status of the underlying skcipher.
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 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>
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>
