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
3631c650c495d61b1dabf32eb26b46873636e918:
<-- 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>
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>
If the underlying algorithm specifies a specific geniv algorithm then
we should use it for the cryptd version as well.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch introduces the geniv field which indicates the default IV
generator for each algorithm. It should point to a string that is not
freed as long as the algorithm is registered.
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>
This patch adds the necessary changes for GCM to be used with async
ciphers. This would allow it to be used with hardware devices that
support CTR.
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>
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>
This patch fixes the request context alignment so that it is actually
aligned to the value required by the algorithm.
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>
i get here:
----
LD vmlinux
SYSMAP System.map
SYSMAP .tmp_System.map
Building modules, stage 2.
MODPOST 226 modules
ERROR: "crypto_hash_type" [crypto/authenc.ko] undefined!
make[1]: *** [__modpost] Error 1
make: *** [modules] Error 2
---
which fails because crypto_hash_type is declared in crypto/hash.c. You might wanna
fix it like so:
Signed-off-by: Borislav Petkov <bbpetkov@yahoo.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a simple speed test for salsa20.
Usage: modprobe tcrypt mode=206
Signed-of-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add common compression tester function
Modify deflate test case to use the common compressor test function
Signed-off-by: Zoltan Sogor <weth@inf.u-szeged.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is a large test vector for Salsa20 that crosses the 4096-bytes
page boundary.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes the multi-page processing bug that affects large test
vectors (the same bug that previously affected ctr.c).
There is an optimization for the case walk.nbytes == nbytes. Also we
now use crypto_xor() instead of adhoc XOR routines.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The abreq structure is currently allocated on the stack. This is broken
if the underlying algorithm is asynchronous. This patch changes it so
that it's taken from the private context instead which has been enlarged
accordingly.
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>
This patch changes gcm/authenc to return EBADMSG instead of EINVAL for
ICV mismatches. This convention has already been adopted by IPsec.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The crypto_aead convention for ICVs is to include it directly in the
output. If we decided to change this in future then we would make
the ICV (if the algorithm has an explicit one) available in the
request itself.
For now no algorithm needs this so this patch changes gcm to conform
to this convention. It also adjusts the tcrypt aead tests to take
this into account.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently the gcm(aes) tests have to be taken together with all other
ciphers. This patch makes it available by itself at number 35.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The previous code incorrectly included the hash in the verification which
also meant that we'd crash and burn when it comes to actually verifying
the hash since we'd go past the end of the SG list.
This patch fixes that by subtracting authsize from cryptlen at the start.
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>
As it is authsize is an algorithm paramter which cannot be changed at
run-time. This is inconvenient because hardware that implements such
algorithms would have to register each authsize that they support
separately.
Since authsize is a property common to all AEAD algorithms, we can add
a function setauthsize that sets it at run-time, just like setkey.
This patch does exactly that and also changes authenc so that authsize
is no longer a parameter of its template.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since alignment masks are always one less than a power of two, we can
use binary or to find their maximum.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
These utilities implemented in lib/hexdump.c are more handy, please use this.
Signed-off-by: Denis Cheng <crquan@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add test vectors to tcrypt for AES in CBC mode for key sizes 192 and 256.
The test vectors are copied from NIST SP800-38A.
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a large AES CTR mode test vector. The test vector is
4100 bytes in size. It was generated using a C++ program that called
Crypto++.
Note that this patch increases considerably the size of "struct
cipher_testvec" and hence the size of tcrypt.ko.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently the number of entries in a cipher test vector template is
limited by TVMEMSIZE/sizeof(struct cipher_testvec). This patch
circumvents the problem by pointing cipher_tv to each entry in the
template, rather than the template itself.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
When the data spans across a page boundary, CTR may incorrectly process
a partial block in the middle because the blkcipher walking code may
supply partial blocks in the middle as long as the total length of the
supplied data is more than a block. CTR is supposed to return any unused
partial block in that case to the walker.
This patch fixes this by doing exactly that, returning partial blocks to
the walker unless we received less than a block-worth of data to start
with.
This also allows us to optimise the bulk of the processing since we no
longer have to worry about partial blocks until the very end.
Thanks to Tan Swee Heng for fixes and actually testing this :)
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
Add AEAD support to tcrypt, needed by 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>
Analogously to camellia7 patch, move
"absorb kw2 to other subkeys" and "absorb kw4 to other subkeys"
code parts into camellia_setup_tail(). This further reduces
source and object code size at the cost of two brances
in key setup code.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move "key XOR is end of F-function" code part into
camellia_setup_tail(), it is sufficiently similar
between camellia_setup128 and camellia_setup256.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
unifies encrypt/decrypt routines for different key lengths.
This reduces module size by ~25%, with tiny (less than 1%)
speed impact.
Also collapses encrypt/decrypt into more readable
(visually shorter) form using macros.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove unused macro params.
Use (u8)(expr) instead of (expr) & 0xff,
helps gcc to realize how to use simpler commands.
Move CAMELLIA_FLS macro closer to encrypt/decrypt routines.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch replaces the custom xor in CBC with the generic crypto_xor.
It changes the operations for in-place encryption slightly to avoid
calling crypto_xor with tmpbuf since it is not necessarily aligned.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
All common block ciphers have a block size that's a power of 2. In fact,
all of our block ciphers obey this rule.
If we require this then CBC can be optimised to avoid an expensive divide
on in-place decryption.
I've also changed the saving of the first IV in the in-place decryption
case to the last IV because that lets us use walk->iv (which is already
aligned) for the xor operation where alignment is required.
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>
This patch converts the crypto scatterwalk code to use the generic
scatterlist chaining rather the version specific to crypto.
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>
The setkey() function can be shared with the generic algorithm.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
NO other block mode is M by default.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The setkey() function can be shared with the generic algorithm.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch exports four tables and the set_key() routine. This ressources
can be shared by other AES implementations (aes-x86_64 for instance).
The decryption key has been turned around (deckey[0] is the first piece
of the key instead of deckey[keylen+20]). The encrypt/decrypt functions
are looking now identical (except they are using different tables and
key).
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds countersize to CTR mode.
The template is now ctr(algo,noncesize,ivsize,countersize).
For example, ctr(aes,4,8,4) indicates the counterblock
will be composed of a salt/nonce that is 4 bytes, an iv
that is 8 bytes and the counter is 4 bytes.
When noncesize + ivsize < blocksize, CTR initializes the
last block - ivsize - noncesize portion of the block to
zero. Otherwise the counter block is composed of the IV
(and nonce if necessary).
If noncesize + ivsize == blocksize, then this indicates that
user is passing in entire counterblock. Thus countersize
indicates the amount of bytes in counterblock to use as
the counter for incrementing. CTR will increment counter
portion by 1, and begin encryption with that value.
Note that CTR assumes the counter portion of the block that
will be incremented is stored in big endian.
Signed-off-by: Joy Latten <latten@austin.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move huge unrolled pieces of code (3 screenfuls) at the end of
128/256 key setup routines into common camellia_setup_tail(),
convert it to loop there.
Loop is still unrolled six times, so performance hit is very small,
code size win is big.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Optimize GETU32 to use 4-byte memcpy (modern gcc will convert
such memcpy to single move instruction on i386).
Original GETU32 did four byte fetches, and shifted/XORed those.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename some macros to shorter names: CAMELLIA_RR8 -> ROR8,
making it easier to understand that it is just a right rotation,
nothing camellia-specific in it.
CAMELLIA_SUBKEY_L() -> SUBKEY_L() - just shorter.
Move be32 <-> cpu conversions out of en/decrypt128/256 and into
camellia_en/decrypt - no reason to have that code duplicated twice.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move code blocks around so that related pieces are closer together:
e.g. CAMELLIA_ROUNDSM macro does not need to be separated
from the rest of the code by huge array of constants.
Remove unused macros (COPY4WORD, SWAP4WORD, XOR4WORD[2])
Drop SUBL(), SUBR() macros which only obscure things.
Same for CAMELLIA_SP1110() macro and KEY_TABLE_TYPE typedef.
Remove useless comments:
/* encryption */ -- well it's obvious enough already!
void camellia_encrypt128(...)
Combine swap with copying at the beginning/end of encrypt/decrypt.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Acked-by: Noriaki TAKAMIYA <takamiya@po.ntts.co.jp>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Currently twofish cipher key setup code
has unrolled loops - approximately 70-100
instructions are repeated 40 times.
As a result, twofish module is the biggest module
in crypto/*.
Unrolling produces x2.5 more code (+18k on i386), and speeds up key
setup by 7%:
unrolled: twofish_setkey/sec: 41128
loop: twofish_setkey/sec: 38148
CALC_K256: ~100 insns each
CALC_K192: ~90 insns
CALC_K: ~70 insns
Attached patch removes this unrolling.
$ size */twofish_common.o
text data bss dec hex filename
37920 0 0 37920 9420 crypto.org/twofish_common.o
13209 0 0 13209 3399 crypto/twofish_common.o
Run tested (modprobe tcrypt reports ok). Please apply.
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This three defines are used in all AES related hardware.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
HIFN driver update to use DES weak key checks (exported in this patch).
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch creates include/crypto/des.h for common macros shared between
DES implementations.
Signed-off-by: Evgeniy Polyakov <johnpol@2ka.mipt.ru>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
As it is crypto_remove_spawn may try to unregister an instance which is
yet to be registered. This patch fixes this by checking whether the
instance has been registered before attempting to remove it.
It also removes a bogus cra_destroy check in crypto_register_instance as
1) it's outside the mutex;
2) we have a check in __crypto_register_alg already.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>