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2019-11-17crypto: ablkcipher - remove deprecated and unused ablkcipher supportArd Biesheuvel
Now that all users of the deprecated ablkcipher interface have been moved to the skcipher interface, ablkcipher is no longer used and can be removed. Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-12-23crypto: skcipher - remove remnants of internal IV generatorsEric Biggers
Remove dead code related to internal IV generators, which are no longer used since they've been replaced with the "seqiv" and "echainiv" templates. The removed code includes: - The "givcipher" (GIVCIPHER) algorithm type. No algorithms are registered with this type anymore, so it's unneeded. - The "const char *geniv" member of aead_alg, ablkcipher_alg, and blkcipher_alg. A few algorithms still set this, but it isn't used anymore except to show via /proc/crypto and CRYPTO_MSG_GETALG. Just hardcode "<default>" or "<none>" in those cases. - The 'skcipher_givcrypt_request' structure, which is never used. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-09crypto: user - clean up report structure copyingEric Biggers
There have been a pretty ridiculous number of issues with initializing the report structures that are copied to userspace by NETLINK_CRYPTO. Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME expansion") replaced some strncpy()s with strlcpy()s, thereby introducing information leaks. Later two other people tried to replace other strncpy()s with strlcpy() too, which would have introduced even more information leaks: - https://lore.kernel.org/patchwork/patch/954991/ - https://patchwork.kernel.org/patch/10434351/ Commit cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") also uses the buggy strlcpy() approach and therefore leaks uninitialized memory to userspace. A fix was proposed, but it was originally incomplete. Seeing as how apparently no one can get this right with the current approach, change all the reporting functions to: - Start by memsetting the report structure to 0. This guarantees it's always initialized, regardless of what happens later. - Initialize all strings using strscpy(). This is safe after the memset, ensures null termination of long strings, avoids unnecessary work, and avoids the -Wstringop-truncation warnings from gcc. - Use sizeof(var) instead of sizeof(type). This is more robust against copy+paste errors. For simplicity, also reuse the -EMSGSIZE return value from nla_put(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03crypto: ablkcipher - fix crash flushing dcache in error pathEric Biggers
Like the skcipher_walk and blkcipher_walk cases: scatterwalk_done() is only meant to be called after a nonzero number of bytes have been processed, since scatterwalk_pagedone() will flush the dcache of the *previous* page. But in the error case of ablkcipher_walk_done(), e.g. if the input wasn't an integer number of blocks, scatterwalk_done() was actually called after advancing 0 bytes. This caused a crash ("BUG: unable to handle kernel paging request") during '!PageSlab(page)' on architectures like arm and arm64 that define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was page-aligned as in that case walk->offset == 0. Fix it by reorganizing ablkcipher_walk_done() to skip the scatterwalk_advance() and scatterwalk_done() if an error has occurred. Reported-by: Liu Chao <liuchao741@huawei.com> Fixes: bf06099db18a ("crypto: skcipher - Add ablkcipher_walk interfaces") Cc: <stable@vger.kernel.org> # v2.6.35+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-09crypto: skcipher - Fix -Wstringop-truncation warningsStafford Horne
As of GCC 9.0.0 the build is reporting warnings like: crypto/ablkcipher.c: In function ‘crypto_ablkcipher_report’: crypto/ablkcipher.c:374:2: warning: ‘strncpy’ specified bound 64 equals destination size [-Wstringop-truncation] strncpy(rblkcipher.geniv, alg->cra_ablkcipher.geniv ?: "<default>", ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ sizeof(rblkcipher.geniv)); ~~~~~~~~~~~~~~~~~~~~~~~~~ This means the strnycpy might create a non null terminated string. Fix this by explicitly performing '\0' termination. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Arnd Bergmann <arnd@arndb.de> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Nick Desaulniers <nick.desaulniers@gmail.com> Signed-off-by: Stafford Horne <shorne@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-13crypto: Replaced gcc specific attributes with macros from compiler.hGideon Israel Dsouza
Continuing from this commit: 52f5684c8e1e ("kernel: use macros from compiler.h instead of __attribute__((...))") I submitted 4 total patches. They are part of task I've taken up to increase compiler portability in the kernel. I've cleaned up the subsystems under /kernel /mm /block and /security, this patch targets /crypto. There is <linux/compiler.h> which provides macros for various gcc specific constructs. Eg: __weak for __attribute__((weak)). I've cleaned all instances of gcc specific attributes with the right macros for the crypto subsystem. I had to make one additional change into compiler-gcc.h for the case when one wants to use this: __attribute__((aligned) and not specify an alignment factor. From the gcc docs, this will result in the largest alignment for that data type on the target machine so I've named the macro __aligned_largest. Please advise if another name is more appropriate. Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-18crypto: skcipher - Remove top-level givcipher interfaceHerbert Xu
This patch removes the old crypto_grab_skcipher helper and replaces it with crypto_grab_skcipher2. As this is the final entry point into givcipher this patch also removes all traces of the top-level givcipher interface, including all implicit IV generators such as chainiv. The bottom-level givcipher interface remains until the drivers using it are converted. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-07crypto: skcipher - remove unused header cpumask.hGeliang Tang
Remove unused header cpumask.h from crypto/ablkcipher.c. Signed-off-by: Geliang Tang <geliangtang@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-09crypto: skcipher - Copy iv from desc even for 0-len walksJason A. Donenfeld
Some ciphers actually support encrypting zero length plaintexts. For example, many AEAD modes support this. The resulting ciphertext for those winds up being only the authentication tag, which is a result of the key, the iv, the additional data, and the fact that the plaintext had zero length. The blkcipher constructors won't copy the IV to the right place, however, when using a zero length input, resulting in some significant problems when ciphers call their initialization routines, only to find that the ->iv parameter is uninitialized. One such example of this would be using chacha20poly1305 with a zero length input, which then calls chacha20, which calls the key setup routine, which eventually OOPSes due to the uninitialized ->iv member. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-10-20crypto: api - Only abort operations on fatal signalHerbert Xu
Currently a number of Crypto API operations may fail when a signal occurs. This causes nasty problems as the caller of those operations are often not in a good position to restart the operation. In fact there is currently no need for those operations to be interrupted by user signals at all. All we need is for them to be killable. This patch replaces the relevant calls of signal_pending with fatal_signal_pending, and wait_for_completion_interruptible with wait_for_completion_killable, respectively. Cc: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-22crypto: skcipher - Allow givencrypt to be NULLHerbert Xu
Currently for skcipher IV generators they must provide givencrypt as that is the whole point. We are currently replacing skcipher IV generators with explicit IV generators. In order to maintain backwards compatibility, we need to allow the IV generators to still function as a normal skcipher when the RNG Is not present (e.g., in the initramfs during boot). IOW everything but givencrypt and givdecrypt will still work but those two will fail. Therefore this patch assigns a default givencrypt that simply returns an error should it be NULL. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-05-25crypto: skcipher - Use tmpl->createHerbert Xu
Newer templates use tmpl->create and have a NULL tmpl->alloc. So we must use tmpl->create if it is set. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-04-26crypto: skcipher - Fix corner case in crypto_lookup_skcipherHerbert Xu
When the user explicitly states that they don't care whether the algorithm has been tested (type = CRYPTO_ALG_TESTED and mask = 0), there is a corner case where we may erroneously return ENOENT. This patch fixes it by correcting the logic in the test. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-01-26crypto: replace scatterwalk_sg_next with sg_nextCristian Stoica
Modify crypto drivers to use the generic SG helper since both of them are equivalent and the one from crypto is redundant. See also: 468577abe37ff7b453a9ac613e0ea155349203ae reverted in b2ab4a57b018aafbba35bff088218f5cc3d2142e Signed-off-by: Cristian Stoica <cristian.stoica@freescale.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-12-22crypto: ablkcipher - fixed style errors in ablkcipher.cJoshua I. James
Fixed style errors reported by checkpatch. WARNING: Missing a blank line after declarations + u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); + return max(start, end_page); WARNING: line over 80 characters + scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg)); WARNING: Missing a blank line after declarations + int err = ablkcipher_copy_iv(walk, tfm, alignmask); + if (err) ERROR: do not use assignment in if condition + if ((err = crypto_register_instance(tmpl, inst))) { Signed-off-by: Joshua I. James <joshua@cybercrimetech.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2013-10-30crypto: skcipher - Use eseqiv even on UP machinesHerbert Xu
Previously we would use eseqiv on all async ciphers in all cases, and sync ciphers if we have more than one CPU. This meant that chainiv is only used in the case of sync ciphers on a UP machine. As chainiv may aid attackers by making the IV predictable, even though this risk itself is small, the above usage pattern causes it to further leak information about the host. This patch addresses these issues by using eseqiv even if we're on a UP machine. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Steffen Klassert <steffen.klassert@secunet.com> Acked-by: David S. Miller <davem@davemloft.net>
2013-02-19crypto: user - fix info leaks in report APIMathias Krause
Three errors resulting in kernel memory disclosure: 1/ The structures used for the netlink based crypto algorithm report API are located on the stack. As snprintf() does not fill the remainder of the buffer with null bytes, those stack bytes will be disclosed to users of the API. Switch to strncpy() to fix this. 2/ crypto_report_one() does not initialize all field of struct crypto_user_alg. Fix this to fix the heap info leak. 3/ For the module name we should copy only as many bytes as module_name() returns -- not as much as the destination buffer could hold. But the current code does not and therefore copies random data from behind the end of the module name, as the module name is always shorter than CRYPTO_MAX_ALG_NAME. Also switch to use strncpy() to copy the algorithm's name and driver_name. They are strings, after all. Signed-off-by: Mathias Krause <minipli@googlemail.com> Cc: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2012-04-10Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2012-04-02crypto: Stop using NLA_PUT*().David S. Miller
These macros contain a hidden goto, and are thus extremely error prone and make code hard to audit. Signed-off-by: David S. Miller <davem@davemloft.net>
2012-03-29crypto: user - Fix lookup of algorithms with IV generatorSteffen Klassert
We lookup algorithms with crypto_alg_mod_lookup() when instantiating via crypto_add_alg(). However, algorithms that are wrapped by an IV genearator (e.g. aead or genicv type algorithms) need special care. The userspace process hangs until it gets a timeout when we use crypto_alg_mod_lookup() to lookup these algorithms. So export the lookup functions for these algorithms and use them in crypto_add_alg(). Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-11-11crypto: algapi - Fix build problem with NET disabledHerbert Xu
The report functions use NLA_PUT so we need to ensure that NET is enabled. Reported-by: Luis Henriques <henrix@camandro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-21crypto: Add userspace report for givcipher type algorithmsSteffen Klassert
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-10-21crypto: Add userspace report for ablkcipher type algorithmsSteffen Klassert
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2011-01-29crypto: skcipher - remove redundant NULL checkDavidlohr Bueso
Signed-off-by: Davidlohr Bueso <dave@gnu.org> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-06-23crypto: skcipher - avoid NULL dereferenceJiri Slaby
Stanse found a potential NULL dereference in ablkcipher_next_slow. Even though kmalloc fails, its retval is dereferenced later. Return from that function properly earlier. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-05-19crypto: skcipher - Add ablkcipher_walk interfacesDavid S. Miller
These are akin to the blkcipher_walk helpers. The main differences in the async variant are: 1) Only physical walking is supported. We can't hold on to kmap mappings across the async operation to support virtual ablkcipher_walk operations anyways. 2) Bounce buffers used for async more need to be persistent and freed at a later point in time when the async op completes. Therefore we maintain a list of writeback buffers and require that the ablkcipher_walk user call the 'complete' operation so we can copy the bounce buffers out to the real buffers and free up the bounce buffer chunks. These interfaces will be used by the new Niagara2 crypto driver. Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-02-16crypto: ablkcipher - Fix checkpatch errorsRichard Hartmann
Signed-off-by: Richard Hartmann <richih.mailinglist@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-08-14crypto: blkcipher - Do not use eseqiv on stream ciphersHerbert Xu
Recently we switched to using eseqiv on SMP machines in preference over chainiv. However, eseqiv does not support stream ciphers so they should still default to chainiv. This patch applies the same check as done by eseqiv to weed out the stream ciphers. In particular, all algorithms where the IV size is not equal to the block size will now default to chainiv. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-25crypto: skcipher - Change default sync geniv on SMP to eseqivHerbert Xu
As it stands we use chainiv for sync algorithms and eseqiv for async algorithms. However, when there is more than one CPU chainiv forces all processing to be serialised which is usually not what you want. Also, the added overhead of eseqiv isn't that great. Therefore this patch changes the default sync geniv on SMP machines to eseqiv. For the odd situation where the overhead is unacceptable then chainiv is still available as an option. Note that on UP machines chainiv is still preferred over eseqiv for sync algorithms. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-06-25crypto: skcipher - Fix request for sync algorithmsHerbert Xu
When a sync givcipher algorithm is requested, if an async version of the same algorithm already exists, then we will loop forever without ever constructing the sync version based on a blkcipher. This is because we did not include the requested type/mask when getting a larval for the geniv algorithm that is to be constructed. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2009-02-18crypto: skcipher - Avoid infinite loop when cipher fails selftestHerbert Xu
When an skcipher constructed through crypto_givcipher_default fails its selftest, we'll loop forever trying to construct new skcipher objects but failing because it already exists. The crux of the issue is that once a givcipher fails the selftest, we'll ignore it on the next run through crypto_skcipher_lookup and attempt to construct a new givcipher. We should instead return an error to the caller if we find a givcipher that has failed the test. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-02-23[CRYPTO] skcipher: Move chainiv/seqiv into crypto_blkcipher moduleHerbert Xu
For compatibility with dm-crypt initramfs setups it is useful to merge chainiv/seqiv into the crypto_blkcipher module. Since they're required by most algorithms anyway this is an acceptable trade-off. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] api: Show async typeHerbert Xu
This patch adds an async field to /proc/crypto for ablkcipher and aead algorithms. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] skcipher: Create default givcipher instancesHerbert Xu
This patch makes crypto_alloc_ablkcipher/crypto_grab_skcipher always return algorithms that are capable of generating their own IVs through givencrypt and givdecrypt. Each algorithm may specify its default IV generator through the geniv field. For algorithms that do not set the geniv field, the blkcipher layer will pick a default. Currently it's chainiv for synchronous algorithms and eseqiv for asynchronous algorithms. Note that if these wrappers do not work on an algorithm then that algorithm must specify its own geniv or it can't be used at all. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] skcipher: Add skcipher_geniv_alloc/skcipher_geniv_freeHerbert Xu
This patch creates the infrastructure to help the construction of givcipher templates that wrap around existing blkcipher/ablkcipher algorithms by adding an IV generator to them. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] skcipher: Added geniv fieldHerbert Xu
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>
2008-01-11[CRYPTO] skcipher: Add givcrypt operations and givcipher typeHerbert Xu
Different block cipher modes have different requirements for intialisation vectors. For example, CBC can use a simple randomly generated IV while modes such as CTR must use an IV generation mechanisms that give a stronger guarantee on the lack of collisions. Furthermore, disk encryption modes have their own IV generation algorithms. Up until now IV generation has been left to the users of the symmetric key cipher API. This is inconvenient as the number of block cipher modes increase because the user needs to be aware of which mode is supposed to be paired with which IV generation algorithm. Therefore it makes sense to integrate the IV generation into the crypto API. This patch takes the first step in that direction by creating two new ablkcipher operations, givencrypt and givdecrypt that generates an IV before performing the actual encryption or decryption. The operations are currently not exposed to the user. That will be done once the underlying functionality has actually been implemented. It also creates the underlying givcipher type. Algorithms that directly generate IVs would use it instead of ablkcipher. All other algorithms (including all existing ones) would generate a givcipher algorithm upon registration. This givcipher algorithm will be constructed from the geniv string that's stored in every algorithm. That string will locate a template which is instantiated by the blkcipher/ablkcipher algorithm in question to give a givcipher algorithm. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2008-01-11[CRYPTO] skcipher: Add crypto_grab_skcipher interfaceHerbert Xu
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>
2007-10-10[CRYPTO] ablkcipher: Remove queue pointer from common alg objectHerbert Xu
Since not everyone needs a queue pointer and those who need it can always get it from the context anyway the queue pointer in the common alg object is redundant. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-10-10[CRYPTO] api: Add missing headers for setkey_unalignedHerbert Xu
This patch ensures that kernel.h and slab.h are included for the setkey_unaligned function. It also breaks a couple of long lines. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-08-06[CRYPTO] api: fix writting into unallocated memory in setkey_alignedSebastian Siewior
setkey_unaligned() commited in ca7c39385ce1a7b44894a4b225a4608624e90730 overwrites unallocated memory in the following memset() because I used the wrong buffer length. Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-07-11[CRYPTO] api: Allow ablkcipher with no queuesSebastian Siewior
Evgeniy's hifn driver and probably mine don't use ablkcipher->queue at all. The show method of ablkcipher will access this field without checking if it is valid. Signed-off-by: Sebastian Siewior <linux-crypto@ml.breakpoint.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-07-11[CRYPTO] api: Handle unaligned keys in setkeySebastian Siewior
setkey() in {cipher,blkcipher,ablkcipher,hash}.c does not respect the requested alignment by the algorithm. This patch fixes it. The extra memory is allocated by kmalloc() with GFP_ATOMIC flag. Signed-off-by: Sebastian Siewior <linux-crypto@ml.breakpoint.cc> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2007-05-02[CRYPTO] api: Add async blkcipher typeHerbert Xu
This patch adds the mid-level interface for asynchronous block ciphers. It also includes a generic queueing mechanism that can be used by other asynchronous crypto operations in future. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>