commit 34c86f4c4a7be3b3e35aa48bd18299d4c756064d upstream.
The locking in af_alg_release_parent is broken as the BH socket
lock can only be taken if there is a code-path to handle the case
where the lock is owned by process-context. Instead of adding
such handling, we can fix this by changing the ref counts to
atomic_t.
This patch also modifies the main refcnt to include both normal
and nokey sockets. This way we don't have to fudge the nokey
ref count when a socket changes from nokey to normal.
Credits go to Mauricio Faria de Oliveira who diagnosed this bug
and sent a patch for it:
https://lore.kernel.org/linux-crypto/20200605161657.535043-1-mfo@canonical.com/
Reported-by: Brian Moyles <bmoyles@netflix.com>
Reported-by: Mauricio Faria de Oliveira <mfo@canonical.com>
Fixes: 37f96694cf73 ("crypto: af_alg - Use bh_lock_sock in...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77251e41f89a813b4090f5199442f217bbf11297 upstream.
When a crypto template needs to be instantiated, CRYPTO_MSG_ALG_REQUEST
is sent to crypto_chain. cryptomgr_schedule_probe() handles this by
starting a thread to instantiate the template, then waiting for this
thread to complete via crypto_larval::completion.
This can deadlock because instantiating the template may require loading
modules, and this (apparently depending on userspace) may need to wait
for the crc-t10dif module (lib/crc-t10dif.c) to be loaded. But
crc-t10dif's module_init function uses crypto_register_notifier() and
therefore takes crypto_chain.rwsem for write. That can't proceed until
the notifier callback has finished, as it holds this semaphore for read.
Fix this by removing the wait on crypto_larval::completion from within
cryptomgr_schedule_probe(). It's actually unnecessary because
crypto_alg_mod_lookup() calls crypto_larval_wait() itself after sending
CRYPTO_MSG_ALG_REQUEST.
This only actually became a problem in v4.20 due to commit b76377543b73
("crc-t10dif: Pick better transform if one becomes available"), but the
unnecessary wait was much older.
BugLink: https://bugzilla.kernel.org/show_bug.cgi?id=207159
Reported-by: Mike Gerow <gerow@google.com>
Fixes: 398710379f ("crypto: algapi - Move larval completion into algboss")
Cc: <stable@vger.kernel.org> # v3.6+
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reported-by: Kai Lüke <kai@kinvolk.io>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7cf81954705b7e5b057f7dc39a7ded54422ab6e1 upstream.
Somewhere along the line the cap on the SG list length for receive
was lost. This patch restores it and removes the subsequent test
which is now redundant.
Fixes: 2d97591ef4 ("crypto: af_alg - consolidation of...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 1a263ae60b04de959d9ce9caea4889385eefcc7b upstream.
gcc-10 has started warning about conflicting types for a few new
built-in functions, particularly 'free()'.
This results in warnings like:
crypto/xts.c:325:13: warning: conflicting types for built-in function ‘free’; expected ‘void(void *)’ [-Wbuiltin-declaration-mismatch]
because the crypto layer had its local freeing functions called
'free()'.
Gcc-10 is in the wrong here, since that function is marked 'static', and
thus there is no chance of confusion with any standard library function
namespace.
But the simplest thing to do is to just use a different name here, and
avoid this gcc mis-feature.
[ Side note: gcc knowing about 'free()' is in itself not the
mis-feature: the semantics of 'free()' are special enough that a
compiler can validly do special things when seeing it.
So the mis-feature here is that gcc thinks that 'free()' is some
restricted name, and you can't shadow it as a local static function.
Making the special 'free()' semantics be a function attribute rather
than tied to the name would be the much better model ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 73669cc556462f4e50376538d77ee312142e8a8a upstream.
The function crypto_spawn_alg is racy because it drops the lock
before shooting the dying algorithm. The algorithm could disappear
altogether before we shoot it.
This patch fixes it by moving the shooting into the locked section.
Fixes: 6bfd48096f ("[CRYPTO] api: Added spawns")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit e8d998264bffade3cfe0536559f712ab9058d654 upstream.
We should not be modifying the original request's MAY_SLEEP flag
upon completion. It makes no sense to do so anyway.
Reported-by: Eric Biggers <ebiggers@kernel.org>
Fixes: 5068c7a883 ("crypto: pcrypt - Add pcrypt crypto...")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7db3b61b6bba4310f454588c2ca6faf2958ad79f upstream.
We need to check whether spawn->alg is NULL under lock as otherwise
the algorithm could be removed from under us after we have checked
it and found it to be non-NULL. This could cause us to remove the
spawn from a non-existent list.
Fixes: 7ede5a5ba5 ("crypto: api - Fix crypto_drop_spawn crash...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 07bfd9bdf568a38d9440c607b72342036011f727 ]
On module unload of pcrypt we must unregister the crypto algorithms
first and then tear down the padata structure. As otherwise the
crypto algorithms are still alive and can be used while the padata
structure is being freed.
Fixes: 5068c7a883 ("crypto: pcrypt - Add pcrypt crypto...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 37f96694cf73ba116993a9d2d99ad6a75fa7fdb0 upstream.
As af_alg_release_parent may be called from BH context (most notably
due to an async request that only completes after socket closure,
or as reported here because of an RCU-delayed sk_destruct call), we
must use bh_lock_sock instead of lock_sock.
Reported-by: syzbot+c2f1558d49e25cc36e5e@syzkaller.appspotmail.com
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Fixes: c840ac6af3 ("crypto: af_alg - Disallow bind/setkey/...")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f990f7fb58ac8ac9a43316f09a48cff1a49dda42 ]
Fix an unaligned memory access in tgr192_transform() by using the
unaligned access helpers.
Fixes: 06ace7a9ba ("[CRYPTO] Use standard byte order macros wherever possible")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b1e3874c75ab15288f573b3532e507c37e8e7656 ]
Passing string 'name' as the format specifier is potentially hazardous
because name could (although very unlikely to) have a format specifier
embedded in it causing issues when parsing the non-existent arguments
to these. Follow best practice by using the "%s" format string for
the string 'name'.
Cleans up clang warning:
crypto/pcrypt.c:397:40: warning: format string is not a string literal
(potentially insecure) [-Wformat-security]
Fixes: a3fb1e330d ("pcrypt: Added sysfs interface to pcrypt")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit ffdde5932042600c6807d46c1550b28b0db6a3bc upstream.
In crypto_report, a new skb is created via nlmsg_new(). This skb should
be released if crypto_report_alg() fails.
Fixes: a38f7907b9 ("crypto: Add userspace configuration API")
Cc: <stable@vger.kernel.org>
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f398243e9fd6a3a059c1ea7b380c40628dbf0c61 upstream.
The elliptic curve arithmetic library used by the EC-DH KPP implementation
assumes big endian byte order, and unconditionally reverses the byte
and word order of multi-limb quantities. On big endian systems, the byte
reordering is not necessary, while the word ordering needs to be retained.
So replace the __swab64() invocation with a call to be64_to_cpu() which
should do the right thing for both little and big endian builds.
Fixes: 3c4b23901a ("crypto: ecdh - Add ECDH software support")
Cc: <stable@vger.kernel.org> # v4.9+
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 64e7f852c47ce99f6c324c46d6a299a5a7ebead9 upstream.
when libkcapi test is executed using HW accelerator, cipher operation
return -74.Since af_alg_async_cb->ki_complete treat err as unsigned int,
libkcapi receive 429467222 even though it expect -ve value.
Hence its required to cast resultlen to int so that proper
error is returned to libkcapi.
AEAD one shot non-aligned test 2(libkcapi test)
./../bin/kcapi -x 10 -c "gcm(aes)" -i 7815d4b06ae50c9c56e87bd7
-k ea38ac0c9b9998c80e28fb496a2b88d9 -a
"853f98a750098bec1aa7497e979e78098155c877879556bb51ddeb6374cbaefc"
-t "c4ce58985b7203094be1d134c1b8ab0b" -q
"b03692f86d1b8b39baf2abb255197c98"
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Cc: <stable@vger.kernel.org>
Signed-off-by: Ayush Sawal <ayush.sawal@chelsio.com>
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ayush Sawal <ayush.sawal@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 2eb4942b6609d35a4e835644a33203b0aef7443d ]
Currently used scalar multiplication algorithm (Matthieu Rivain, 2011)
have invalid values for scalar == 1, n-1, and for regularized version
n-2, which was previously not checked. Verify that they are not used as
private keys.
Signed-off-by: Vitaly Chikunov <vt@altlinux.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 0ac6b8fb23c724b015d9ca70a89126e8d1563166 ]
CRYPTO_MSG_GETALG in NLM_F_DUMP mode sometimes doesn't return all
registered crypto algorithms, because it doesn't support incremental
dumps. crypto_dump_report() only permits itself to be called once, yet
the netlink subsystem allocates at most ~64 KiB for the skb being dumped
to. Thus only the first recvmsg() returns data, and it may only include
a subset of the crypto algorithms even if the user buffer passed to
recvmsg() is large enough to hold all of them.
Fix this by using one of the arguments in the netlink_callback structure
to keep track of the current position in the algorithm list. Then
userspace can do multiple recvmsg() on the socket after sending the dump
request. This is the way netlink dumps work elsewhere in the kernel;
it's unclear why this was different (probably just an oversight).
Also fix an integer overflow when calculating the dump buffer size hint.
Fixes: a38f7907b9 ("crypto: Add userspace configuration API")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 3944f139d5592790b70bc64f197162e643a8512b ]
The encryption mode of pkcs1pad never uses out_sg and out_buf, so
there's no need to allocate the buffer, which presently is not even
being freed.
CC: Herbert Xu <herbert@gondor.apana.org.au>
CC: linux-crypto@vger.kernel.org
CC: "David S. Miller" <davem@davemloft.net>
Signed-off-by: Dan Aloni <dan@kernelim.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 0ba3c026e685573bd3534c17e27da7c505ac99c4 upstream.
skcipher_walk_done may be called with an error by internal or
external callers. For those internal callers we shouldn't unmap
pages but for external callers we must unmap any pages that are
in use.
This patch distinguishes between the two cases by checking whether
walk->nbytes is zero or not. For internal callers, we now set
walk->nbytes to zero prior to the call. For external callers,
walk->nbytes has always been non-zero (as zero is used to indicate
the termination of a walk).
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Fixes: 5cde0af2a9 ("[CRYPTO] cipher: Added block cipher type")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 7545b6c2087f4ef0287c8c9b7eba6a728c67ff8e upstream.
Clear the CRYPTO_TFM_REQ_MAY_SLEEP flag when the chacha20poly1305
operation is being continued from an async completion callback, since
sleeping may not be allowed in that context.
This is basically the same bug that was recently fixed in the xts and
lrw templates. But, it's always been broken in chacha20poly1305 too.
This was found using syzkaller in combination with the updated crypto
self-tests which actually test the MAY_SLEEP flag now.
Reproducer:
python -c 'import socket; socket.socket(socket.AF_ALG, 5, 0).bind(
("aead", "rfc7539(cryptd(chacha20-generic),poly1305-generic)"))'
Kernel output:
BUG: sleeping function called from invalid context at include/crypto/algapi.h:426
in_atomic(): 1, irqs_disabled(): 0, pid: 1001, name: kworker/2:2
[...]
CPU: 2 PID: 1001 Comm: kworker/2:2 Not tainted 5.2.0-rc2 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014
Workqueue: crypto cryptd_queue_worker
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x4d/0x6a lib/dump_stack.c:113
___might_sleep kernel/sched/core.c:6138 [inline]
___might_sleep.cold.19+0x8e/0x9f kernel/sched/core.c:6095
crypto_yield include/crypto/algapi.h:426 [inline]
crypto_hash_walk_done+0xd6/0x100 crypto/ahash.c:113
shash_ahash_update+0x41/0x60 crypto/shash.c:251
shash_async_update+0xd/0x10 crypto/shash.c:260
crypto_ahash_update include/crypto/hash.h:539 [inline]
poly_setkey+0xf6/0x130 crypto/chacha20poly1305.c:337
poly_init+0x51/0x60 crypto/chacha20poly1305.c:364
async_done_continue crypto/chacha20poly1305.c:78 [inline]
poly_genkey_done+0x15/0x30 crypto/chacha20poly1305.c:369
cryptd_skcipher_complete+0x29/0x70 crypto/cryptd.c:279
cryptd_skcipher_decrypt+0xcd/0x110 crypto/cryptd.c:339
cryptd_queue_worker+0x70/0xa0 crypto/cryptd.c:184
process_one_work+0x1ed/0x420 kernel/workqueue.c:2269
worker_thread+0x3e/0x3a0 kernel/workqueue.c:2415
kthread+0x11f/0x140 kernel/kthread.c:255
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Fixes: 71ebc4d1b2 ("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539")
Cc: <stable@vger.kernel.org> # v4.2+
Cc: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5c6bc4dfa515738149998bb0db2481a4fdead979 upstream.
Changing ghash_mod_init() to be subsys_initcall made it start running
before the alignment fault handler has been installed on ARM. In kernel
builds where the keys in the ghash test vectors happened to be
misaligned in the kernel image, this exposed the longstanding bug that
ghash_setkey() is incorrectly casting the key buffer (which can have any
alignment) to be128 for passing to gf128mul_init_4k_lle().
Fix this by memcpy()ing the key to a temporary buffer.
Don't fix it by setting an alignmask on the algorithm instead because
that would unnecessarily force alignment of the data too.
Fixes: 2cdc6899a8 ("crypto: ghash - Add GHASH digest algorithm for GCM")
Reported-by: Peter Robinson <pbrobinson@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Tested-by: Peter Robinson <pbrobinson@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 90acc0653d2bee203174e66d519fbaaa513502de ]
Build testing with some core crypto options disabled revealed
a few modules that are missing CRYPTO_HASH:
crypto/asymmetric_keys/x509_public_key.o: In function `x509_get_sig_params':
x509_public_key.c:(.text+0x4c7): undefined reference to `crypto_alloc_shash'
x509_public_key.c:(.text+0x5e5): undefined reference to `crypto_shash_digest'
crypto/asymmetric_keys/pkcs7_verify.o: In function `pkcs7_digest.isra.0':
pkcs7_verify.c:(.text+0xab): undefined reference to `crypto_alloc_shash'
pkcs7_verify.c:(.text+0x1b2): undefined reference to `crypto_shash_digest'
pkcs7_verify.c:(.text+0x3c1): undefined reference to `crypto_shash_update'
pkcs7_verify.c:(.text+0x411): undefined reference to `crypto_shash_finup'
This normally doesn't show up in randconfig tests because there is
a large number of other options that select CRYPTO_HASH.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 473971187d6727609951858c63bf12b0307ef015 ]
The same bug that gcc hit in the past is apparently now showing
up with clang, which decides to inline __serpent_setkey_sbox:
crypto/serpent_generic.c:268:5: error: stack frame size of 2112 bytes in function '__serpent_setkey' [-Werror,-Wframe-larger-than=]
Marking it 'noinline' reduces the stack usage from 2112 bytes to
192 and 96 bytes, respectively, and seems to generate more
useful object code.
Fixes: c871c10e4e ("crypto: serpent - improve __serpent_setkey with UBSAN")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 1a0fad630e0b7cff38e7691b28b0517cfbb0633f upstream.
cryptd_skcipher_free() fails to free the struct skcipher_instance
allocated in cryptd_create_skcipher(), leading to a memory leak. This
is detected by kmemleak on bootup on ARM64 platforms:
unreferenced object 0xffff80003377b180 (size 1024):
comm "cryptomgr_probe", pid 822, jiffies 4294894830 (age 52.760s)
backtrace:
kmem_cache_alloc_trace+0x270/0x2d0
cryptd_create+0x990/0x124c
cryptomgr_probe+0x5c/0x1e8
kthread+0x258/0x318
ret_from_fork+0x10/0x1c
Fixes: 4e0958d19b ("crypto: cryptd - Add support for skcipher")
Cc: <stable@vger.kernel.org>
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 21d4120ec6f5b5992b01b96ac484701163917b63 upstream.
Michal Suchanek reported [1] that running the pcrypt_aead01 test from
LTP [2] in a loop and holding Ctrl-C causes a NULL dereference of
alg->cra_users.next in crypto_remove_spawns(), via crypto_del_alg().
The test repeatedly uses CRYPTO_MSG_NEWALG and CRYPTO_MSG_DELALG.
The crash occurs when the instance that CRYPTO_MSG_DELALG is trying to
unregister isn't a real registered algorithm, but rather is a "test
larval", which is a special "algorithm" added to the algorithms list
while the real algorithm is still being tested. Larvals don't have
initialized cra_users, so that causes the crash. Normally pcrypt_aead01
doesn't trigger this because CRYPTO_MSG_NEWALG waits for the algorithm
to be tested; however, CRYPTO_MSG_NEWALG returns early when interrupted.
Everything else in the "crypto user configuration" API has this same bug
too, i.e. it inappropriately allows operating on larval algorithms
(though it doesn't look like the other cases can cause a crash).
Fix this by making crypto_alg_match() exclude larval algorithms.
[1] https://lkml.kernel.org/r/20190625071624.27039-1-msuchanek@suse.de
[2] https://github.com/linux-test-project/ltp/blob/20190517/testcases/kernel/crypto/pcrypt_aead01.c
Reported-by: Michal Suchanek <msuchanek@suse.de>
Fixes: a38f7907b9 ("crypto: Add userspace configuration API")
Cc: <stable@vger.kernel.org> # v3.2+
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 6a1faa4a43f5fabf9cbeaa742d916e7b5e73120f upstream.
CCM instances can be created by either the "ccm" template, which only
allows choosing the block cipher, e.g. "ccm(aes)"; or by "ccm_base",
which allows choosing the ctr and cbcmac implementations, e.g.
"ccm_base(ctr(aes-generic),cbcmac(aes-generic))".
However, a "ccm_base" instance prevents a "ccm" instance from being
registered using the same implementations. Nor will the instance be
found by lookups of "ccm". This can be used as a denial of service.
Moreover, "ccm_base" instances are never tested by the crypto
self-tests, even if there are compatible "ccm" tests.
The root cause of these problems is that instances of the two templates
use different cra_names. Therefore, fix these problems by making
"ccm_base" instances set the same cra_name as "ccm" instances, e.g.
"ccm(aes)" instead of "ccm_base(ctr(aes-generic),cbcmac(aes-generic))".
This requires extracting the block cipher name from the name of the ctr
and cbcmac algorithms. It also requires starting to verify that the
algorithms are really ctr and cbcmac using the same block cipher, not
something else entirely. But it would be bizarre if anyone were
actually using non-ccm-compatible algorithms with ccm_base, so this
shouldn't break anyone in practice.
Fixes: 4a49b499df ("[CRYPTO] ccm: Added CCM mode")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit edaf28e996af69222b2cb40455dbb5459c2b875a upstream.
If the user-provided IV needs to be aligned to the algorithm's
alignmask, then skcipher_walk_virt() copies the IV into a new aligned
buffer walk.iv. But skcipher_walk_virt() can fail afterwards, and then
if the caller unconditionally accesses walk.iv, it's a use-after-free.
salsa20-generic doesn't set an alignmask, so currently it isn't affected
by this despite unconditionally accessing walk.iv. However this is more
subtle than desired, and it was actually broken prior to the alignmask
being removed by commit b62b3db76f73 ("crypto: salsa20-generic - cleanup
and convert to skcipher API").
Since salsa20-generic does not update the IV and does not need any IV
alignment, update it to use req->iv instead of walk.iv.
Fixes: 2407d60872 ("[CRYPTO] salsa20: Salsa20 stream cipher")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit f699594d436960160f6d5ba84ed4a222f20d11cd upstream.
GCM instances can be created by either the "gcm" template, which only
allows choosing the block cipher, e.g. "gcm(aes)"; or by "gcm_base",
which allows choosing the ctr and ghash implementations, e.g.
"gcm_base(ctr(aes-generic),ghash-generic)".
However, a "gcm_base" instance prevents a "gcm" instance from being
registered using the same implementations. Nor will the instance be
found by lookups of "gcm". This can be used as a denial of service.
Moreover, "gcm_base" instances are never tested by the crypto
self-tests, even if there are compatible "gcm" tests.
The root cause of these problems is that instances of the two templates
use different cra_names. Therefore, fix these problems by making
"gcm_base" instances set the same cra_name as "gcm" instances, e.g.
"gcm(aes)" instead of "gcm_base(ctr(aes-generic),ghash-generic)".
This requires extracting the block cipher name from the name of the ctr
algorithm. It also requires starting to verify that the algorithms are
really ctr and ghash, not something else entirely. But it would be
bizarre if anyone were actually using non-gcm-compatible algorithms with
gcm_base, so this shouldn't break anyone in practice.
Fixes: d00aa19b50 ("[CRYPTO] gcm: Allow block cipher parameter")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 307508d1072979f4435416f87936f87eaeb82054 upstream.
The ->digest() method of crct10dif-generic reads the current CRC value
from the shash_desc context. But this value is uninitialized, causing
crypto_shash_digest() to compute the wrong result. Fix it.
Probably this wasn't noticed before because lib/crc-t10dif.c only uses
crypto_shash_update(), not crypto_shash_digest(). Likewise,
crypto_shash_digest() is not yet tested by the crypto self-tests because
those only test the ahash API which only uses shash init/update/final.
This bug was detected by my patches that improve testmgr to fuzz
algorithms against their generic implementation.
Fixes: 2d31e518a4 ("crypto: crct10dif - Wrap crc_t10dif function all to use crypto transform framework")
Cc: <stable@vger.kernel.org> # v3.11+
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit dcaca01a42cc2c425154a13412b4124293a6e11e upstream.
skcipher_walk_done() assumes it's a bug if, after the "slow" path is
executed where the next chunk of data is processed via a bounce buffer,
the algorithm says it didn't process all bytes. Thus it WARNs on this.
However, this can happen legitimately when the message needs to be
evenly divisible into "blocks" but isn't, and the algorithm has a
'walksize' greater than the block size. For example, ecb-aes-neonbs
sets 'walksize' to 128 bytes and only supports messages evenly divisible
into 16-byte blocks. If, say, 17 message bytes remain but they straddle
scatterlist elements, the skcipher_walk code will take the "slow" path
and pass the algorithm all 17 bytes in the bounce buffer. But the
algorithm will only be able to process 16 bytes, triggering the WARN.
Fix this by just removing the WARN_ON(). Returning -EINVAL, as the code
already does, is the right behavior.
This bug was detected by my patches that improve testmgr to fuzz
algorithms against their generic implementation.
Fixes: b286d8b1a6 ("crypto: skcipher - Add skcipher walk interface")
Cc: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 5e27f38f1f3f45a0c938299c3a34a2d2db77165a upstream.
If the rfc7539 template is instantiated with specific implementations,
e.g. "rfc7539(chacha20-generic,poly1305-generic)" rather than
"rfc7539(chacha20,poly1305)", then the implementation names end up
included in the instance's cra_name. This is incorrect because it then
prevents all users from allocating "rfc7539(chacha20,poly1305)", if the
highest priority implementations of chacha20 and poly1305 were selected.
Also, the self-tests aren't run on an instance allocated in this way.
Fix it by setting the instance's cra_name from the underlying
algorithms' actual cra_names, rather than from the requested names.
This matches what other templates do.
Fixes: 71ebc4d1b2 ("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539")
Cc: <stable@vger.kernel.org> # v4.2+
Cc: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 678cce4019d746da6c680c48ba9e6d417803e127 upstream.
The x86_64 implementation of Poly1305 produces the wrong result on some
inputs because poly1305_4block_avx2() incorrectly assumes that when
partially reducing the accumulator, the bits carried from limb 'd4' to
limb 'h0' fit in a 32-bit integer. This is true for poly1305-generic
which processes only one block at a time. However, it's not true for
the AVX2 implementation, which processes 4 blocks at a time and
therefore can produce intermediate limbs about 4x larger.
Fix it by making the relevant calculations use 64-bit arithmetic rather
than 32-bit. Note that most of the carries already used 64-bit
arithmetic, but the d4 -> h0 carry was different for some reason.
To be safe I also made the same change to the corresponding SSE2 code,
though that only operates on 1 or 2 blocks at a time. I don't think
it's really needed for poly1305_block_sse2(), but it doesn't hurt
because it's already x86_64 code. It *might* be needed for
poly1305_2block_sse2(), but overflows aren't easy to reproduce there.
This bug was originally detected by my patches that improve testmgr to
fuzz algorithms against their generic implementation. But also add a
test vector which reproduces it directly (in the AVX2 case).
Fixes: b1ccc8f4b6 ("crypto: poly1305 - Add a four block AVX2 variant for x86_64")
Fixes: c70f4abef0 ("crypto: poly1305 - Add a SSE2 SIMD variant for x86_64")
Cc: <stable@vger.kernel.org> # v4.3+
Cc: Martin Willi <martin@strongswan.org>
Cc: Jason A. Donenfeld <Jason@zx2c4.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 251b7aea34ba3c4d4fdfa9447695642eb8b8b098 upstream.
The memcpy()s in the PCBC implementation use walk->iv as both the source
and destination, which has undefined behavior. These memcpy()'s are
actually unneeded, because walk->iv is already used to hold the previous
plaintext block XOR'd with the previous ciphertext block. Thus,
walk->iv is already updated to its final value.
So remove the broken and unnecessary memcpy()s.
Fixes: 91652be5d1 ("[CRYPTO] pcbc: Add Propagated CBC template")
Cc: <stable@vger.kernel.org> # v2.6.21+
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Maxim Zhukov <mussitantesmortem@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit eb5e6730db98fcc4b51148b4a819fa4bf864ae54 upstream.
Instantiating "cryptd(crc32c)" causes a crypto self-test failure because
the crypto_alloc_shash() in alg_test_crc32c() fails. This is because
cryptd(crc32c) is an ahash algorithm, not a shash algorithm; so it can
only be accessed through the ahash API, unlike shash algorithms which
can be accessed through both the ahash and shash APIs.
As the test is testing the shash descriptor format which is only
applicable to shash algorithms, skip it for ahash algorithms.
(Note that it's still important to fix crypto self-test failures even
for weird algorithm instantiations like cryptd(crc32c) that no one
would really use; in fips_enabled mode unprivileged users can use them
to panic the kernel, and also they prevent treating a crypto self-test
failure as a bug when fuzzing the kernel.)
Fixes: 8e3ee85e68 ("crypto: crc32c - Test descriptor context format")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit ba7d7433a0e998c902132bd47330e355a1eaa894 upstream.
Some algorithms have a ->setkey() method that is not atomic, in the
sense that setting a key can fail after changes were already made to the
tfm context. In this case, if a key was already set the tfm can end up
in a state that corresponds to neither the old key nor the new key.
It's not feasible to make all ->setkey() methods atomic, especially ones
that have to key multiple sub-tfms. Therefore, make the crypto API set
CRYPTO_TFM_NEED_KEY if ->setkey() fails and the algorithm requires a
key, to prevent the tfm from being used until a new key is set.
Note: we can't set CRYPTO_TFM_NEED_KEY for OPTIONAL_KEY algorithms, so
->setkey() for those must nevertheless be atomic. That's fine for now
since only the crc32 and crc32c algorithms set OPTIONAL_KEY, and it's
not intended that OPTIONAL_KEY be used much.
[Cc stable mainly because when introducing the NEED_KEY flag I changed
AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG
previously didn't have this problem. So these "incompletely keyed"
states became theoretically accessible via AF_ALG -- though, the
opportunities for causing real mischief seem pretty limited.]
Fixes: 9fa68f620041 ("crypto: hash - prevent using keyed hashes without setting key")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
commit 77568e535af7c4f97eaef1e555bf0af83772456c upstream.
Hash algorithms with an alignmask set, e.g. "xcbc(aes-aesni)" and
"michael_mic", fail the improved hash tests because they sometimes
produce the wrong digest. The bug is that in the case where a
scatterlist element crosses pages, not all the data is actually hashed
because the scatterlist walk terminates too early. This happens because
the 'nbytes' variable in crypto_hash_walk_done() is assigned the number
of bytes remaining in the page, then later interpreted as the number of
bytes remaining in the scatterlist element. Fix it.
Fixes: 900a081f6912 ("crypto: ahash - Fix early termination in hash walk")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 0a6a40c2a8c184a2fb467efacfb1cd338d719e0b ]
In the "aes-fixed-time" AES implementation, disable interrupts while
accessing the S-box, in order to make cache-timing attacks more
difficult. Previously it was possible for the CPU to be interrupted
while the S-box was loaded into L1 cache, potentially evicting the
cachelines and causing later table lookups to be time-variant.
In tests I did on x86 and ARM, this doesn't affect performance
significantly. Responsiveness is potentially a concern, but interrupts
are only disabled for a single AES block.
Note that even after this change, the implementation still isn't
necessarily guaranteed to be constant-time; see
https://cr.yp.to/antiforgery/cachetiming-20050414.pdf for a discussion
of the many difficulties involved in writing truly constant-time AES
software. But it's valuable to make such attacks more difficult.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
commit 8f9c469348487844328e162db57112f7d347c49f upstream.
Keys for "authenc" AEADs are formatted as an rtattr containing a 4-byte
'enckeylen', followed by an authentication key and an encryption key.
crypto_authenc_extractkeys() parses the key to find the inner keys.
However, it fails to consider the case where the rtattr's payload is
longer than 4 bytes but not 4-byte aligned, and where the key ends
before the next 4-byte aligned boundary. In this case, 'keylen -=
RTA_ALIGN(rta->rta_len);' underflows to a value near UINT_MAX. This
causes a buffer overread and crash during crypto_ahash_setkey().
Fix it by restricting the rtattr payload to the expected size.
Reproducer using AF_ALG:
#include <linux/if_alg.h>
#include <linux/rtnetlink.h>
#include <sys/socket.h>
int main()
{
int fd;
struct sockaddr_alg addr = {
.salg_type = "aead",
.salg_name = "authenc(hmac(sha256),cbc(aes))",
};
struct {
struct rtattr attr;
__be32 enckeylen;
char keys[1];
} __attribute__((packed)) key = {
.attr.rta_len = sizeof(key),
.attr.rta_type = 1 /* CRYPTO_AUTHENC_KEYA_PARAM */,
};
fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(fd, (void *)&addr, sizeof(addr));
setsockopt(fd, SOL_ALG, ALG_SET_KEY, &key, sizeof(key));
}
It caused:
BUG: unable to handle kernel paging request at ffff88007ffdc000
PGD 2e01067 P4D 2e01067 PUD 2e04067 PMD 2e05067 PTE 0
Oops: 0000 [#1] SMP
CPU: 0 PID: 883 Comm: authenc Not tainted 4.20.0-rc1-00108-g00c9fe37a7f27 #13
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014
RIP: 0010:sha256_ni_transform+0xb3/0x330 arch/x86/crypto/sha256_ni_asm.S:155
[...]
Call Trace:
sha256_ni_finup+0x10/0x20 arch/x86/crypto/sha256_ssse3_glue.c:321
crypto_shash_finup+0x1a/0x30 crypto/shash.c:178
shash_digest_unaligned+0x45/0x60 crypto/shash.c:186
crypto_shash_digest+0x24/0x40 crypto/shash.c:202
hmac_setkey+0x135/0x1e0 crypto/hmac.c:66
crypto_shash_setkey+0x2b/0xb0 crypto/shash.c:66
shash_async_setkey+0x10/0x20 crypto/shash.c:223
crypto_ahash_setkey+0x2d/0xa0 crypto/ahash.c:202
crypto_authenc_setkey+0x68/0x100 crypto/authenc.c:96
crypto_aead_setkey+0x2a/0xc0 crypto/aead.c:62
aead_setkey+0xc/0x10 crypto/algif_aead.c:526
alg_setkey crypto/af_alg.c:223 [inline]
alg_setsockopt+0xfe/0x130 crypto/af_alg.c:256
__sys_setsockopt+0x6d/0xd0 net/socket.c:1902
__do_sys_setsockopt net/socket.c:1913 [inline]
__se_sys_setsockopt net/socket.c:1910 [inline]
__x64_sys_setsockopt+0x1f/0x30 net/socket.c:1910
do_syscall_64+0x4a/0x180 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fixes: e236d4a89a ("[CRYPTO] authenc: Move enckeylen into key itself")
Cc: <stable@vger.kernel.org> # v2.6.25+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto_grab_*() doesn't set crypto_spawn::inst, so templates must set it
beforehand. Otherwise it will be left NULL, which causes a crash in
certain cases where algorithms are dynamically loaded/unloaded. E.g.
with CONFIG_CRYPTO_CHACHA20_X86_64=m, the following caused a crash:
insmod chacha-x86_64.ko
python -c 'import socket; socket.socket(socket.AF_ALG, 5, 0).bind(("skcipher", "adiantum(xchacha12,aes)"))'
rmmod chacha-x86_64.ko
python -c 'import socket; socket.socket(socket.AF_ALG, 5, 0).bind(("skcipher", "adiantum(xchacha12,aes)"))'
Fixes: 059c2a4d8e16 ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 6db43410179bc40419a9859ebb333f178a49829d)
Test: Adiantum self-tests
Change-Id: I248548c979b0ee9e63a35f8ae779741bb5967b6e
crypto_alg_mod_lookup() takes a reference to the hash algorithm but
crypto_init_shash_spawn() doesn't take ownership of it, hence the
reference needs to be dropped in adiantum_create().
Fixes: 059c2a4d8e16 ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 00c9fe37a7f27a306bcaa5737f0787fe139f8aba)
Test: Adiantum self-tests
Change-Id: Ic609144bc3c72cc2c4ccbbaf450168193f3df7db
The 2018-11-28 revision of the Adiantum paper has revised some notation:
- 'M' was replaced with 'L' (meaning "Left", for the left-hand part of
the message) in the definition of Adiantum hashing, to avoid confusion
with the full message
- ε-almost-∆-universal is now abbreviated as ε-∆U instead of εA∆U
- "block" is now used only to mean block cipher and Poly1305 blocks
Also, Adiantum hashing was moved from the appendix to the main paper.
To avoid confusion, update relevant comments in the code to match.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit c6018e1a00b5c70610cdfb3650cc5622c917ed17)
Test: Adiantum self-tests
Change-Id: Idd371e46408a449f7ff2ba77af2d4414979aadbf
If the stream cipher implementation is asynchronous, then the Adiantum
instance must be flagged as asynchronous as well. Otherwise someone
asking for a synchronous algorithm can get an asynchronous algorithm.
There are no asynchronous xchacha12 or xchacha20 implementations yet
which makes this largely a theoretical issue, but it should be fixed.
Fixes: 059c2a4d8e16 ("crypto: adiantum - add Adiantum support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit b299362ee48db8eab34208302ee9730ff9d6091c)
Test: Adiantum self-tests
Change-Id: Ic7207e4036a0f03fba81375ffe36f511af2eb08c
Add support for the Adiantum encryption mode. Adiantum was designed by
Paul Crowley and is specified by our paper:
Adiantum: length-preserving encryption for entry-level processors
(https://eprint.iacr.org/2018/720.pdf)
See our paper for full details; this patch only provides an overview.
Adiantum is a tweakable, length-preserving encryption mode designed for
fast and secure disk encryption, especially on CPUs without dedicated
crypto instructions. Adiantum encrypts each sector using the XChaCha12
stream cipher, two passes of an ε-almost-∆-universal (εA∆U) hash
function, and an invocation of the AES-256 block cipher on a single
16-byte block. On CPUs without AES instructions, Adiantum is much
faster than AES-XTS; for example, on ARM Cortex-A7, on 4096-byte sectors
Adiantum encryption is about 4 times faster than AES-256-XTS encryption,
and decryption about 5 times faster.
Adiantum is a specialization of the more general HBSH construction. Our
earlier proposal, HPolyC, was also a HBSH specialization, but it used a
different εA∆U hash function, one based on Poly1305 only. Adiantum's
εA∆U hash function, which is based primarily on the "NH" hash function
like that used in UMAC (RFC4418), is about twice as fast as HPolyC's;
consequently, Adiantum is about 20% faster than HPolyC.
This speed comes with no loss of security: Adiantum is provably just as
secure as HPolyC, in fact slightly *more* secure. Like HPolyC,
Adiantum's security is reducible to that of XChaCha12 and AES-256,
subject to a security bound. XChaCha12 itself has a security reduction
to ChaCha12. Therefore, one need not "trust" Adiantum; one need only
trust ChaCha12 and AES-256. Note that the εA∆U hash function is only
used for its proven combinatorical properties so cannot be "broken".
Adiantum is also a true wide-block encryption mode, so flipping any
plaintext bit in the sector scrambles the entire ciphertext, and vice
versa. No other such mode is available in the kernel currently; doing
the same with XTS scrambles only 16 bytes. Adiantum also supports
arbitrary-length tweaks and naturally supports any length input >= 16
bytes without needing "ciphertext stealing".
For the stream cipher, Adiantum uses XChaCha12 rather than XChaCha20 in
order to make encryption feasible on the widest range of devices.
Although the 20-round variant is quite popular, the best known attacks
on ChaCha are on only 7 rounds, so ChaCha12 still has a substantial
security margin; in fact, larger than AES-256's. 12-round Salsa20 is
also the eSTREAM recommendation. For the block cipher, Adiantum uses
AES-256, despite it having a lower security margin than XChaCha12 and
needing table lookups, due to AES's extensive adoption and analysis
making it the obvious first choice. Nevertheless, for flexibility this
patch also permits the "adiantum" template to be instantiated with
XChaCha20 and/or with an alternate block cipher.
We need Adiantum support in the kernel for use in dm-crypt and fscrypt,
where currently the only other suitable options are block cipher modes
such as AES-XTS. A big problem with this is that many low-end mobile
devices (e.g. Android Go phones sold primarily in developing countries,
as well as some smartwatches) still have CPUs that lack AES
instructions, e.g. ARM Cortex-A7. Sadly, AES-XTS encryption is much too
slow to be viable on these devices. We did find that some "lightweight"
block ciphers are fast enough, but these suffer from problems such as
not having much cryptanalysis or being too controversial.
The ChaCha stream cipher has excellent performance but is insecure to
use directly for disk encryption, since each sector's IV is reused each
time it is overwritten. Even restricting the threat model to offline
attacks only isn't enough, since modern flash storage devices don't
guarantee that "overwrites" are really overwrites, due to wear-leveling.
Adiantum avoids this problem by constructing a
"tweakable super-pseudorandom permutation"; this is the strongest
possible security model for length-preserving encryption.
Of course, storing random nonces along with the ciphertext would be the
ideal solution. But doing that with existing hardware and filesystems
runs into major practical problems; in most cases it would require data
journaling (like dm-integrity) which severely degrades performance.
Thus, for now length-preserving encryption is still needed.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 059c2a4d8e164dccc3078e49e7f286023b019a98
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Conflicts:
crypto/tcrypt.c
crypto/testmgr.c
(adjusted test vector formatting for old testmgr)
Bug: 112008522
Test: Among other things, I ran the relevant crypto self-tests:
1.) Build kernel with CONFIG_CRYPTO_MANAGER_DISABLE_TESTS *unset*, and
all relevant crypto algorithms built-in, including:
CONFIG_CRYPTO_ADIANTUM=y
CONFIG_CRYPTO_CHACHA20=y
CONFIG_CRYPTO_CHACHA20_NEON=y
CONFIG_CRYPTO_NHPOLY1305=y
CONFIG_CRYPTO_NHPOLY1305_NEON=y
CONFIG_CRYPTO_POLY1305=y
CONFIG_CRYPTO_AES=y
CONFIG_CRYPTO_AES_ARM=y
2.) Boot and check dmesg for test failures.
3.) Instantiate "adiantum(xchacha12,aes)" and
"adiantum(xchacha20,aes)" to trigger them to be tested. There are
many ways to do this, but one way is to create a dm-crypt target
that uses them, e.g.
key=$(hexdump -n 32 -e '16/4 "%08X" 1 "\n"' /dev/urandom)
dmsetup create crypt --table "0 $((1<<17)) crypt xchacha12,aes-adiantum-plain64 $key 0 /dev/vdc 0"
dmsetup remove crypt
dmsetup create crypt --table "0 $((1<<17)) crypt xchacha20,aes-adiantum-plain64 $key 0 /dev/vdc 0"
dmsetup remove crypt
4.) Check dmesg for test failures again.
5.) Do 1-4 on both x86_64 (for basic testing) and on arm32 (for
testing the ARM32-specific implementations). I did the arm32 kernel
testing on Raspberry Pi 2, which is a BCM2836-based device that can
run the upstream and Android common kernels.
The same ARM32 assembly files for ChaCha, NHPoly1305, and AES are
also included in the userspace Adiantum benchmark suite at
https://github.com/google/adiantum, where they have undergone
additional correctness testing.
Change-Id: Ic61c13b53facfd2173065be715a7ee5f3af8760b
Signed-off-by: Eric Biggers <ebiggers@google.com>
Add a generic implementation of NHPoly1305, an ε-almost-∆-universal hash
function used in the Adiantum encryption mode.
CONFIG_NHPOLY1305 is not selectable by itself since there won't be any
real reason to enable it without also enabling Adiantum support.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 26609a21a9460145e37d90947ad957b358a05288
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Conflicts:
crypto/testmgr.c
crypto/testmgr.h
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: If6f00c01fab530fc2458c44ca111f84604cb85c1
Signed-off-by: Eric Biggers <ebiggers@google.com>
Expose a low-level Poly1305 API which implements the
ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305 MAC
and supports block-aligned inputs only.
This is needed for Adiantum hashing, which builds an εA∆U hash function
from NH and a polynomial evaluation in GF(2^{130}-5); this polynomial
evaluation is identical to the one the Poly1305 MAC does. However, the
crypto_shash Poly1305 API isn't very appropriate for this because its
calling convention assumes it is used as a MAC, with a 32-byte "one-time
key" provided for every digest.
But by design, in Adiantum hashing the performance of the polynomial
evaluation isn't nearly as critical as NH. So it suffices to just have
some C helper functions. Thus, this patch adds such functions.
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 1b6fd3d5d18bbc1b1abf3b0cbc4b95a9a63d407b
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: I5c7da7832b84dfe29c300e117a158740d3e39069
Signed-off-by: Eric Biggers <ebiggers@google.com>
In preparation for exposing a low-level Poly1305 API which implements
the ε-almost-∆-universal (εA∆U) hash function underlying the Poly1305
MAC and supports block-aligned inputs only, create structures
poly1305_key and poly1305_state which hold the limbs of the Poly1305
"r" key and accumulator, respectively.
These structures could actually have the same type (e.g. poly1305_val),
but different types are preferable, to prevent misuse.
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 878afc35cd28bcd93cd3c5e1985ef39a104a4d45
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: If20a0f9d29d8ba1efd43a5eb3fafce7720afe565
Signed-off-by: Eric Biggers <ebiggers@google.com>
Now that the generic implementation of ChaCha20 has been refactored to
allow varying the number of rounds, add support for XChaCha12, which is
the XSalsa construction applied to ChaCha12. ChaCha12 is one of the
three ciphers specified by the original ChaCha paper
(https://cr.yp.to/chacha/chacha-20080128.pdf: "ChaCha, a variant of
Salsa20"), alongside ChaCha8 and ChaCha20. ChaCha12 is faster than
ChaCha20 but has a lower, but still large, security margin.
We need XChaCha12 support so that it can be used in the Adiantum
encryption mode, which enables disk/file encryption on low-end mobile
devices where AES-XTS is too slow as the CPUs lack AES instructions.
We'd prefer XChaCha20 (the more popular variant), but it's too slow on
some of our target devices, so at least in some cases we do need the
XChaCha12-based version. In more detail, the problem is that Adiantum
is still much slower than we're happy with, and encryption still has a
quite noticeable effect on the feel of low-end devices. Users and
vendors push back hard against encryption that degrades the user
experience, which always risks encryption being disabled entirely. So
we need to choose the fastest option that gives us a solid margin of
security, and here that's XChaCha12. The best known attack on ChaCha
breaks only 7 rounds and has 2^235 time complexity, so ChaCha12's
security margin is still better than AES-256's. Much has been learned
about cryptanalysis of ARX ciphers since Salsa20 was originally designed
in 2005, and it now seems we can be comfortable with a smaller number of
rounds. The eSTREAM project also suggests the 12-round version of
Salsa20 as providing the best balance among the different variants:
combining very good performance with a "comfortable margin of security".
Note that it would be trivial to add vanilla ChaCha12 in addition to
XChaCha12. However, it's unneeded for now and therefore is omitted.
As discussed in the patch that introduced XChaCha20 support, I
considered splitting the code into separate chacha-common, chacha20,
xchacha20, and xchacha12 modules, so that these algorithms could be
enabled/disabled independently. However, since nearly all the code is
shared anyway, I ultimately decided there would have been little benefit
to the added complexity.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit aa7624093cb7fbf4fea95e612580d8d29a819f67
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
(adjusted test vector formatting for old testmgr)
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: I876a5be92e9f583effcd35a4b66a36608ac581f0
Signed-off-by: Eric Biggers <ebiggers@google.com>
In preparation for adding XChaCha12 support, rename/refactor
chacha20-generic to support different numbers of rounds. The
justification for needing XChaCha12 support is explained in more detail
in the patch "crypto: chacha - add XChaCha12 support".
The only difference between ChaCha{8,12,20} are the number of rounds
itself; all other parts of the algorithm are the same. Therefore,
remove the "20" from all definitions, structures, functions, files, etc.
that will be shared by all ChaCha versions.
Also make ->setkey() store the round count in the chacha_ctx (previously
chacha20_ctx). The generic code then passes the round count through to
chacha_block(). There will be a ->setkey() function for each explicitly
allowed round count; the encrypt/decrypt functions will be the same. I
decided not to do it the opposite way (same ->setkey() function for all
round counts, with different encrypt/decrypt functions) because that
would have required more boilerplate code in architecture-specific
implementations of ChaCha and XChaCha.
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Acked-by: Martin Willi <martin@strongswan.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
(cherry picked from commit 1ca1b917940c24ca3d1f490118c5474168622953
https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master)
Conflicts:
arch/arm64/crypto/chacha20-neon-glue.c
arch/x86/crypto/chacha20_glue.c
drivers/crypto/caam/caamalg.c
drivers/crypto/caam/caamalg_qi2.c
drivers/crypto/caam/compat.h
include/crypto/chacha20.h
Bug: 112008522
Test: As series, see Ic61c13b53facfd2173065be715a7ee5f3af8760b
Change-Id: I7fa203ddc7095ce8675a32f49b8a5230cd0cf5f6
Signed-off-by: Eric Biggers <ebiggers@google.com>
Simon1511