commit 6bf37e5aa90f18baf5acf4874bca505dd667c37f upstream.
When comparing MAC hashes, AEAD authentication tags, or other hash
values in the context of authentication or integrity checking, it
is important not to leak timing information to a potential attacker,
i.e. when communication happens over a network.
Bytewise memory comparisons (such as memcmp) are usually optimized so
that they return a nonzero value as soon as a mismatch is found. E.g,
on x86_64/i5 for 512 bytes this can be ~50 cyc for a full mismatch
and up to ~850 cyc for a full match (cold). This early-return behavior
can leak timing information as a side channel, allowing an attacker to
iteratively guess the correct result.
This patch adds a new method crypto_memneq ("memory not equal to each
other") to the crypto API that compares memory areas of the same length
in roughly "constant time" (cache misses could change the timing, but
since they don't reveal information about the content of the strings
being compared, they are effectively benign). Iow, best and worst case
behaviour take the same amount of time to complete (in contrast to
memcmp).
Note that crypto_memneq (unlike memcmp) can only be used to test for
equality or inequality, NOT for lexicographical order. This, however,
is not an issue for its use-cases within the crypto API.
We tried to locate all of the places in the crypto API where memcmp was
being used for authentication or integrity checking, and convert them
over to crypto_memneq.
crypto_memneq is declared noinline, placed in its own source file,
and compiled with optimizations that might increase code size disabled
("Os") because a smart compiler (or LTO) might notice that the return
value is always compared against zero/nonzero, and might then
reintroduce the same early-return optimization that we are trying to
avoid.
Using #pragma or __attribute__ optimization annotations of the code
for disabling optimization was avoided as it seems to be considered
broken or unmaintained for long time in GCC [1]. Therefore, we work
around that by specifying the compile flag for memneq.o directly in
the Makefile. We found that this seems to be most appropriate.
As we use ("Os"), this patch also provides a loop-free "fast-path" for
frequently used 16 byte digests. Similarly to kernel library string
functions, leave an option for future even further optimized architecture
specific assembler implementations.
This was a joint work of James Yonan and Daniel Borkmann. Also thanks
for feedback from Florian Weimer on this and earlier proposals [2].
[1] http://gcc.gnu.org/ml/gcc/2012-07/msg00211.html
[2] https://lkml.org/lkml/2013/2/10/131
Signed-off-by: James Yonan <james@openvpn.net>
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Florian Weimer <fw@deneb.enyo.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
commit a5596d6332787fd383b3b5427b41f94254430827 upstream.
This patch adds a way for ahash users to determine whether a key
is required by a crypto_ahash transform.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
commit 37766586c965d63758ad542325a96d5384f4a8c9 upstream.
This patch adds a compatibility path to support old applications
that do acept(2) before setkey.
Cc: stable@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
commit c840ac6af3f8713a71b4d2363419145760bd6044 upstream.
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded. An accept(2) call on that
parent socket creates a context which then uses the tfm object.
Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.
This patch guarantees this by using locks and a reference count
on the parent socket. Any attempt to modify the parent socket will
fail with EBUSY.
Cc: stable@vger.kernel.org
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Signed-off-by: Willy Tarreau <w@1wt.eu>
This reverts commit 5a707f0972 which is
commit c840ac6af3f8713a71b4d2363419145760bd6044 upstream.
It's been widely reported that this patch breaks existing userspace
applications when backported to the stable kernel releases. As no fix
seems to be forthcoming, just revert it to let systems work again.
Reported-by: "J. Paul Reed" <preed@sigkill.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit c840ac6af3f8713a71b4d2363419145760bd6044 upstream.
Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded. An accept(2) call on that
parent socket creates a context which then uses the tfm object.
Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.
This patch guarantees this by using locks and a reference count
on the parent socket. Any attempt to modify the parent socket will
fail with EBUSY.
Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 389a5390583a18e45bc4abd4439291abec5e7a63 upstream.
Now that scatterwalk_sg_chain sets the chain pointer bit the sg_page
call in scatterwalk_sg_next hits a BUG_ON when CONFIG_DEBUG_SG is
enabled. Use sg_chain_ptr instead of sg_page on a chain entry.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 41da8b5adba77e22584f8b45f9641504fa885308 upstream.
The scatterwalk_crypto_chain function invokes the scatterwalk_sg_chain
function to chain two scatterlists, but the chain pointer indication
bit is not set. When the resulting scatterlist is used, for example,
by sg_nents to count the number of scatterlist entries, a segfault occurs
because sg_nents does not follow the chain pointer to the chained scatterlist.
Update scatterwalk_sg_chain to set the chain pointer indication bit as is
done by the sg_chain function.
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
VMAC implementation, as it is, does not work with blocks that
are not multiples of 128-bytes. Furthermore, this is a problem
when using the implementation on scatterlists, even
when the complete plain text is 128-byte multiple, as the pieces
that get passed to vmac_update can be pretty much any size.
I also added test cases for unaligned blocks.
Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Pull module signing support from Rusty Russell:
"module signing is the highlight, but it's an all-over David Howells frenzy..."
Hmm "Magrathea: Glacier signing key". Somebody has been reading too much HHGTTG.
* 'modules-next' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (37 commits)
X.509: Fix indefinite length element skip error handling
X.509: Convert some printk calls to pr_devel
asymmetric keys: fix printk format warning
MODSIGN: Fix 32-bit overflow in X.509 certificate validity date checking
MODSIGN: Make mrproper should remove generated files.
MODSIGN: Use utf8 strings in signer's name in autogenerated X.509 certs
MODSIGN: Use the same digest for the autogen key sig as for the module sig
MODSIGN: Sign modules during the build process
MODSIGN: Provide a script for generating a key ID from an X.509 cert
MODSIGN: Implement module signature checking
MODSIGN: Provide module signing public keys to the kernel
MODSIGN: Automatically generate module signing keys if missing
MODSIGN: Provide Kconfig options
MODSIGN: Provide gitignore and make clean rules for extra files
MODSIGN: Add FIPS policy
module: signature checking hook
X.509: Add a crypto key parser for binary (DER) X.509 certificates
MPILIB: Provide a function to read raw data into an MPI
X.509: Add an ASN.1 decoder
X.509: Add simple ASN.1 grammar compiler
...
Provide signature verification using an asymmetric-type key to indicate the
public key to be used.
The API is a single function that can be found in crypto/public_key.h:
int verify_signature(const struct key *key,
const struct public_key_signature *sig)
The first argument is the appropriate key to be used and the second argument
is the parsed signature data:
struct public_key_signature {
u8 *digest;
u16 digest_size;
enum pkey_hash_algo pkey_hash_algo : 8;
union {
MPI mpi[2];
struct {
MPI s; /* m^d mod n */
} rsa;
struct {
MPI r;
MPI s;
} dsa;
};
};
This should be filled in prior to calling the function. The hash algorithm
should already have been called and the hash finalised and the output should
be in a buffer pointed to by the 'digest' member.
Any extra data to be added to the hash by the hash format (eg. PGP) should
have been added by the caller prior to finalising the hash.
It is assumed that the signature is made up of a number of MPI values. If an
algorithm becomes available for which this is not the case, the above structure
will have to change.
It is also assumed that it will have been checked that the signature algorithm
matches the key algorithm.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Add a subtype for supporting asymmetric public-key encryption algorithms such
as DSA (FIPS-186) and RSA (PKCS#1 / RFC1337).
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Rename cast6 module to cast6_generic to allow autoloading of optimized
implementations. Generic functions and s-boxes are exported to be able to use
them within optimized implementations.
Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Rename cast5 module to cast5_generic to allow autoloading of optimized
implementations. Generic functions and s-boxes are exported to be able to use
them within optimized implementations.
Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add crypto_[un]register_shashes() to allow simplifying init/exit code of shash
crypto modules that register multiple algorithms.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
We leak the crypto instance when we unregister an instance with
crypto_del_alg(). Therefore we introduce crypto_unregister_instance()
to unlink the crypto instance from the template's instances list and
to free the recources of the instance properly.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Add xts_crypt() function that can be used by cipher implementations that can
benefit from parallelized cipher operations.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Export gf128mul table initialization routines and add lrw_crypt() function
that can be used by cipher implementations that can benefit from parallelized
cipher operations.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Serpent SSE2 assembler implementations only provide 4-way/8-way parallel
functions and need setkey and one-block encrypt/decrypt functions.
CC: Dag Arne Osvik <osvik@ii.uib.no>
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We add a report function pointer to struct crypto_type. This function
pointer is used from the crypto userspace configuration API to report
crypto algorithms to userspace.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Patch splits up the blowfish crypto routine into a common part (key setup)
which will be used by blowfish crypto modules (x86_64 assembly and generic-c).
Also fixes errors/warnings reported by checkpatch.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On Tue, Aug 16, 2011 at 03:22:34PM +1000, Stephen Rothwell wrote:
>
> After merging the final tree, today's linux-next build (powerpc
> allyesconfig) produced this warning:
>
> In file included from security/integrity/ima/../integrity.h:16:0,
> from security/integrity/ima/ima.h:27,
> from security/integrity/ima/ima_policy.c:20:
> include/crypto/sha.h:86:10: warning: 'struct shash_desc' declared inside parameter list
> include/crypto/sha.h:86:10: warning: its scope is only this definition or declaration, which is probably not what you want
>
> Introduced by commit 7c390170b4 ("crypto: sha1 - export sha1_update for
> reuse"). I guess you need to include crypto/hash.h in crypto/sha.h.
This patch fixes this by providing a declaration for struct shash_desc.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Export the update function as crypto_sha1_update() to not have the need
to reimplement the same algorithm for each SHA-1 implementation. This
way the generic SHA-1 implementation can be used as fallback for other
implementations that fail to run under certain circumstances, like the
need for an FPU context while executing in IRQ context.
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Remove linux/mm.h inclusion from netdevice.h -- it's unused (I've checked manually).
To prevent mm.h inclusion via other channels also extract "enum dma_data_direction"
definition into separate header. This tiny piece is what gluing netdevice.h with mm.h
via "netdevice.h => dmaengine.h => dma-mapping.h => scatterlist.h => mm.h".
Removal of mm.h from scatterlist.h was tried and was found not feasible
on most archs, so the link was cutoff earlier.
Hope people are OK with tiny include file.
Note, that mm_types.h is still dragged in, but it is a separate story.
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch moves padlock.h from drivers/crypto into include/crypto
so that it may be used by the via-rng driver.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
A lot of crypto algorithms implement their own chaining function.
So add a generic one that can be used from all the algorithms that
need scatterlist chaining.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch creates the backbone of the user-space interface for
the Crypto API, through a new socket family AF_ALG.
Each session corresponds to one or more connections obtained from
that socket. The number depends on the number of inputs/outputs
of that particular type of operation. For most types there will
be a s ingle connection/file descriptor that is used for both input
and output. AEAD is one of the few that require two inputs.
Each algorithm type will provide its own implementation that plugs
into af_alg. They're keyed using a string such as "skcipher" or
"hash".
IOW this patch only contains the boring bits that is required
to hold everything together.
Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Martin Willi <martin@strongswan.org>
This patch adds AEAD support into the cryptd framework. Having AEAD
support in cryptd enables crypto drivers that use the AEAD
interface type (such as the patch for AEAD based RFC4106 AES-GCM
implementation using Intel New Instructions) to leverage cryptd for
asynchronous processing.
Signed-off-by: Adrian Hoban <adrian.hoban@intel.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Signed-off-by: Gabriele Paoloni <gabriele.paoloni@intel.com>
Signed-off-by: Aidan O'Mahony <aidan.o.mahony@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
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>
This patch adds export/import support to md5. The exported type is
defined by struct md5_state.
This is modeled after the equivalent change to sha1_generic.
Signed-off-by: Max Vozeler <max@hinterhof.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds a parallel crypto template that takes a crypto
algorithm and converts it to process the crypto transforms in
parallel. For the moment only aead algorithms are supported.
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
6941c3a0 disabled compilation of the legacy digest code but didn't
actually remove it. Rectify this. Also, remove the crypto_hash_type
extern declaration from algapi.h now that the struct is gone.
Signed-off-by: Benjamin Gilbert <bgilbert@cs.cmu.edu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
PCLMULQDQ is used to accelerate the most time-consuming part of GHASH,
carry-less multiplication. More information about PCLMULQDQ can be
found at:
http://software.intel.com/en-us/articles/carry-less-multiplication-and-its-usage-for-computing-the-gcm-mode/
Because PCLMULQDQ changes XMM state, its usage must be enclosed with
kernel_fpu_begin/end, which can be used only in process context, the
acceleration is implemented as crypto_ahash. That is, request in soft
IRQ context will be defered to the cryptd kernel thread.
Signed-off-by: Huang Ying <ying.huang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Stricted