When I backed out of using the generic sg chaining (as it isn't currently
portable) and introduced scatterwalk_sg_chain/scatterwalk_sg_next I left
out the sg_is_last check in the latter. This causes it to potentially
dereference beyond the end of the sg array.
As most uses of scatterwalk_sg_next are bound by an overall length, this
only affected the chaining code in authenc and eseqiv. Thanks to Patrick
McHardy for identifying this problem.
This patch also clears the "last" bit on the head of the chained list as
it's no longer last. This also went missing in scatterwalk_sg_chain and
is present in sg_chain.
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>
The previous patch to move chainiv and eseqiv into blkcipher created
a section mismatch for the chainiv exit function which was also called
from __init. This patch removes the __exit marking on it.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
For compatibility with dm-crypt initramfs setups it is useful to merge
chainiv/seqiv into the crypto_blkcipher module. Since they're required
by most algorithms anyway this is an acceptable trade-off.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As Andrew Morton correctly points out, we need to explicitly include
sched.h as we use the function cond_resched in crypto/scatterwalk.h.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes chainiv avoid spinning by postponing requests on lock
contention if the user allows the use of asynchronous algorithms. If
a synchronous algorithm is requested then we behave as before.
This should improve IPsec performance on SMP when two CPUs attempt to
transmit over the same SA. Currently one of them will spin doing nothing
waiting for the other CPU to finish its encryption. This patch makes it
postpone the request and get on with other work.
If only one CPU is transmitting for a given SA, then we will process
the request synchronously as before.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a null blkcipher algorithm called ecb(cipher_null) for
backwards compatibility. Previously the null algorithm when used by
IPsec copied the data byte by byte. This new algorithm optimises that
to a straight memcpy which lets us better measure inherent overheads in
our IPsec code.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes crypto_alloc_aead always return algorithms that is
capable of generating their own IVs through givencrypt and givdecrypt.
All existing AEAD algorithms already do. New ones must either supply
their own or specify a generic IV generator with the geniv field.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch creates the infrastructure to help the construction of IV
generator templates that wrap around AEAD algorithms by adding an IV
generator to them. This is useful for AEAD algorithms with no built-in
IV generator or to replace their built-in generator.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch finally makes the givencrypt/givdecrypt operations available
to users by adding crypto_aead_givencrypt and crypto_aead_givdecrypt.
A suite of helpers to allocate and fill in the request is also available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the underlying givcrypt operations for aead and associated
support elements. The rationale is identical to that of the skcipher
givcrypt operations, i.e., sometimes only the algorithm knows how the
IV should be generated.
A new request type aead_givcrypt_request is added which contains an
embedded aead_request structure with two new elements to support this
operation. The new elements are seq and giv. The seq field should
contain a strictly increasing 64-bit integer which may be used by
certain IV generators as an input value. The giv field will be used
to store the generated IV. It does not need to obey the alignment
requirements of the algorithm because it's not used during the operation.
The existing iv field must still be available as it will be used to store
intermediate IVs and the output IV if chaining is desired.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch finally makes the givencrypt/givdecrypt operations available
to users by adding crypto_skcipher_givencrypt and crypto_skcipher_givdecrypt.
A suite of helpers to allocate and fill in the request is also available.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Now that gcm and authenc have been converted to crypto_spawn_skcipher,
this patch removes the obsolete crypto_spawn_ablkcipher function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes crypto_alloc_ablkcipher/crypto_grab_skcipher always
return algorithms that are capable of generating their own IVs through
givencrypt and givdecrypt. Each algorithm may specify its default IV
generator through the geniv field.
For algorithms that do not set the geniv field, the blkcipher layer will
pick a default. Currently it's chainiv for synchronous algorithms and
eseqiv for asynchronous algorithms. Note that if these wrappers do not
work on an algorithm then that algorithm must specify its own geniv or
it can't be used at all.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the helper skcipher_givcrypt_complete which should be
called when an ablkcipher algorithm has completed a givcrypt request.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch creates the infrastructure to help the construction of givcipher
templates that wrap around existing blkcipher/ablkcipher algorithms by adding
an IV generator to them.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Different block cipher modes have different requirements for intialisation
vectors. For example, CBC can use a simple randomly generated IV while
modes such as CTR must use an IV generation mechanisms that give a stronger
guarantee on the lack of collisions. Furthermore, disk encryption modes
have their own IV generation algorithms.
Up until now IV generation has been left to the users of the symmetric
key cipher API. This is inconvenient as the number of block cipher modes
increase because the user needs to be aware of which mode is supposed to
be paired with which IV generation algorithm.
Therefore it makes sense to integrate the IV generation into the crypto
API. This patch takes the first step in that direction by creating two
new ablkcipher operations, givencrypt and givdecrypt that generates an
IV before performing the actual encryption or decryption.
The operations are currently not exposed to the user. That will be done
once the underlying functionality has actually been implemented.
It also creates the underlying givcipher type. Algorithms that directly
generate IVs would use it instead of ablkcipher. All other algorithms
(including all existing ones) would generate a givcipher algorithm upon
registration. This givcipher algorithm will be constructed from the geniv
string that's stored in every algorithm. That string will locate a template
which is instantiated by the blkcipher/ablkcipher algorithm in question to
give a givcipher algorithm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Note: From now on the collective of ablkcipher/blkcipher/givcipher will
be known as skcipher, i.e., symmetric key cipher. The name blkcipher has
always been much of a misnomer since it supports stream ciphers too.
This patch adds the function crypto_grab_skcipher as a new way of getting
an ablkcipher spawn. The problem is that previously we did this in two
steps, first getting the algorithm and then calling crypto_init_spawn.
This meant that each spawn user had to be aware of what type and mask to
use for these two steps. This is difficult and also presents a problem
when the type/mask changes as they're about to be for IV generators.
The new interface does both steps together just like crypto_alloc_ablkcipher.
As a side-effect this also allows us to be stronger on type enforcement
for spawns. For now this is only done for ablkcipher but it's trivial
to extend for other types.
This patch also moves the type/mask logic for skcipher into the helpers
crypto_skcipher_type and crypto_skcipher_mask.
Finally this patch introduces the function crypto_require_sync to determine
whether the user is specifically requesting a sync algorithm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As discussed previously, this patch moves the basic CTR functionality
into a chainable algorithm called ctr. The IPsec-specific variant of
it is now placed on top with the name rfc3686.
So ctr(aes) gives a chainable cipher with IV size 16 while the IPsec
variant will be called rfc3686(ctr(aes)). This patch also adjusts
gcm accordingly.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a new helper crypto_attr_alg_name which is basically the
first half of crypto_attr_alg. That is, it returns an algorithm name
parameter as a string without looking it up. The caller can then look it
up immediately or defer it until later.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Unfortunately the generic chaining hasn't been ported to all architectures
yet, and notably not s390. So this patch restores the chainging that we've
been using previously which does work everywhere.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The scatterwalk infrastructure is used by algorithms so it needs to
move out of crypto for future users that may live in drivers/crypto
or asm/*/crypto.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Having enckeylen as a template parameter makes it a pain for hardware
devices that implement ciphers with many key sizes since each one would
have to be registered separately.
Since the authenc algorithm is mainly used for legacy purposes where its
key is going to be constructed out of two separate keys, we can in fact
embed this value into the key itself.
This patch does this by prepending an rtnetlink header to the key that
contains the encryption key length.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With the addition of more stream ciphers we need to curb the proliferation
of ad-hoc xor functions. This patch creates a generic pair of functions,
crypto_inc and crypto_xor which does big-endian increment and exclusive or,
respectively.
For optimum performance, they both use u32 operations so alignment must be
as that of u32 even though the arguments are of type u8 *.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Up until now we have ablkcipher algorithms have been identified as
type BLKCIPHER with the ASYNC bit set. This is suboptimal because
ablkcipher refers to two things. On the one hand it refers to the
top-level ablkcipher interface with requests. On the other hand it
refers to and algorithm type underneath.
As it is you cannot request a synchronous block cipher algorithm
with the ablkcipher interface on top. This is a problem because
we want to be able to eventually phase out the blkcipher top-level
interface.
This patch fixes this by making ABLKCIPHER its own type, just as
we have distinct types for HASH and DIGEST. The type it associated
with the algorithm implementation only.
Which top-level interface is used for synchronous block ciphers is
then determined by the mask that's used. If it's a specific mask
then the old blkcipher interface is given, otherwise we go with the
new ablkcipher interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Resubmitting this patch which extends sha256_generic.c to support SHA-224 as
described in FIPS 180-2 and RFC 3874. HMAC-SHA-224 as described in RFC4231
is then supported through the hmac interface.
Patch includes test vectors for SHA-224 and HMAC-SHA-224.
SHA-224 chould be chosen as a hash algorithm when 112 bits of security
strength is required.
Patch generated against the 2.6.24-rc1 kernel and tested against
2.6.24-rc1-git14 which includes fix for scatter gather implementation for HMAC.
Signed-off-by: Jonathan Lynch <jonathan.lynch@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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 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>
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>
There are currently several SHA implementations that all define their own
initialization vectors and size values. Since this values are idential
move them to a header file under include/crypto.
Signed-off-by: Jan Glauber <jang@de.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the helper blkcipher_walk_virt_block which is similar to
blkcipher_walk_virt but uses a supplied block size instead of the block
size of the block cipher. This is useful for CTR where the block size is
1 but we still want to walk by the block size of the underlying cipher.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
XTS currently considered to be the successor of the LRW mode by the IEEE1619
workgroup. LRW was discarded, because it was not secure if the encyption key
itself is encrypted with LRW.
XTS does not have this problem. The implementation is pretty straightforward,
a new function was added to gf128mul to handle GF(128) elements in ble format.
Four testvectors from the specification
http://grouper.ieee.org/groups/1619/email/pdf00086.pdf
were added, and they verify on my system.
Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the authenc algorithm which constructs an AEAD algorithm
from an asynchronous block cipher and a hash. The construction is done
by concatenating the encrypted result from the cipher with the output
from the hash, as is used by the IPsec ESP protocol.
The authenc algorithm exists as a template with four parameters:
authenc(auth, authsize, enc, enckeylen).
The authentication algorithm, the authentication size (i.e., truncating
the output of the authentication algorithm), the encryption algorithm,
and the encryption key length. Both the size field and the key length
field are in bytes. For example, AES-128 with SHA1-HMAC would be
represented by
authenc(hmac(sha1), 12, cbc(aes), 16)
The key for the authenc algorithm is the concatenation of the keys for
the authentication algorithm with the encryption algorithm. For the
above example, if a key of length 36 bytes is given, then hmac(sha1)
would receive the first 20 bytes while the last 16 would be given to
cbc(aes).
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch adds crypto_aead which is the interface for AEAD
(Authenticated Encryption with Associated Data) algorithms.
AEAD algorithms perform authentication and encryption in one
step. Traditionally users (such as IPsec) would use two
different crypto algorithms to perform these. With AEAD
this comes down to one algorithm and one operation.
Of course if traditional algorithms were used we'd still
be doing two operations underneath. However, real AEAD
algorithms may allow the underlying operations to be
optimised as well.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This is function does the same thing for ablkcipher that is done for
blkcipher by crypto_blkcipher_ctx_aligned(): it returns an aligned
address of the private ctx.
Signed-off-by: Sebastian Siewior <sebastian@breakpoint.cc>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the cryptd module which is a template that takes a
synchronous software crypto algorithm and converts it to an asynchronous
one by executing it in a kernel thread.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As it is whenever a new algorithm with the same name is registered
users of the old algorithm will be removed so that they can take
advantage of the new algorithm. This presents a problem when the
new algorithm is not equivalent to the old algorithm. In particular,
the new algorithm might only function on top of the existing one.
Hence we should not remove users unless they can make use of the
new algorithm.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch passes the type/mask along when constructing instances of
templates. This is in preparation for templates that may support
multiple types of instances depending on what is requested. For example,
the planned software async crypto driver will use this construct.
For the moment this allows us to check whether the instance constructed
is of the correct type and avoid returning success if the type does not
match.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds support for multiple frontend types for each backend
algorithm by passing the type and mask through to the backend type
init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
A lot of cypher modes need multiplications in GF(2^128). LRW, ABL, GCM...
I use functions from this library in my LRW implementation and I will
also use them in my ABL (Arbitrary Block Length, an unencumbered (correct
me if I am wrong, wide block cipher mode).
Elements of GF(2^128) must be presented as u128 *, it encourages automatic
and proper alignment.
The library contains support for two different representations of GF(2^128),
see the comment in gf128mul.h. There different levels of optimization
(memory/speed tradeoff).
The code is based on work by Dr Brian Gladman. Notable changes:
- deletion of two optimization modes
- change from u32 to u64 for faster handling on 64bit machines
- support for 'bbe' representation in addition to the, already implemented,
'lle' representation.
- move 'inline void' functions from header to 'static void' in the
source file
- update to use the linux coding style conventions
The original can be found at:
http://fp.gladman.plus.com/AES/modes.vc8.19-06-06.zip
The copyright (and GPL statement) of the original author is preserved.
Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
128bit is a common blocksize in linux kernel cryptography, so it helps to
centralize some common operations.
The code, while mostly trivial, is based on a header file mode_hdr.h in
http://fp.gladman.plus.com/AES/modes.vc8.19-06-06.zip
The original copyright (and GPL statement) of the original author,
Dr Brian Gladman, is preserved.
Signed-off-by: Rik Snel <rsnel@cube.dyndns.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The existing digest user interface is inadequate for support asynchronous
operations. For one it doesn't return a value to indicate success or
failure, nor does it take a per-operation descriptor which is essential
for the issuing of requests while other requests are still outstanding.
This patch is the first in a series of steps to remodel the interface
for asynchronous operations.
For the ease of transition the new interface will be known as "hash"
while the old one will remain as "digest".
This patch also changes sg_next to allow chaining.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds two block cipher algorithms, CBC and ECB. These
are implemented as templates on top of existing single-block cipher
algorithms. They invoke the single-block cipher through the new
encrypt_one/decrypt_one interface.
This also optimises the in-place encryption and decryption to remove
the cost of an IV copy each round.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the new type of block ciphers. Unlike current cipher
algorithms which operate on a single block at a time, block ciphers
operate on an arbitrarily long linear area of data. As it is block-based,
it will skip any data remaining at the end which cannot form a block.
The block cipher has one major difference when compared to the existing
block cipher implementation. The sg walking is now performed by the
algorithm rather than the cipher mid-layer. This is needed for drivers
that directly support sg lists. It also improves performance for all
algorithms as it reduces the total number of indirect calls by one.
In future the existing cipher algorithm will be converted to only have
a single-block interface. This will be done after all existing users
have switched over to the new block cipher type.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch prepares the scatterwalk code for use by the new block cipher
type.
Firstly it halves the size of scatter_walk on 32-bit platforms. This
is important as we allocate at least two of these objects on the stack
for each block cipher operation.
It also exports the symbols since the block cipher code can be built as
a module.
Finally there is a hack in scatterwalk_unmap that relies on progress
being made. Unfortunately, for hardware crypto we can't guarantee
progress to be made since the hardware can fail.
So this also gets rid of the hack by not advancing the address returned
by scatterwalk_map.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds two new operations for the simple cipher that encrypts or
decrypts a single block at a time. This will be the main interface after
the existing block operations have moved over to the new block ciphers.
It also adds the crypto_cipher type which is currently only used on the
new operations but will be extended to setkey as well once existing users
have been converted to use block ciphers where applicable.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the crypto_type structure which will be used for all new
crypto algorithm types, beginning with block ciphers.
The primary purpose of this abstraction is to allow different crypto_type
objects for crypto algorithms of the same type, in particular, there will
be a different crypto_type objects for asynchronous algorithms.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
