Be more verbose and also report ->backend_cra_name when
crypto_alloc_shash() or crypto_alloc_cipher() fail in
drbg_init_hash_kernel() or drbg_init_sym_kernel()
correspondingly.
Example
DRBG: could not allocate digest TFM handle: hmac(sha256)
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As required by SP800-90A, the DRBG implements are reseeding threshold.
This threshold is at 2**48 (64 bit) and 2**32 bit (32 bit) as
implemented in drbg_max_requests.
With the recently introduced changes, the DRBG is now always used as a
stdrng which is initialized very early in the boot cycle. To ensure that
sufficient entropy is present, the Jitter RNG is added to even provide
entropy at early boot time.
However, the 2nd seed source, the nonblocking pool, is usually
degraded at that time. Therefore, the DRBG is seeded with the Jitter RNG
(which I believe contains good entropy, which however is questioned by
others) and is seeded with a degradded nonblocking pool. This seed is
now used for quasi the lifetime of the system (2**48 requests is a lot).
The patch now changes the reseed threshold as follows: up until the time
the DRBG obtains a seed from a fully iniitialized nonblocking pool, the
reseeding threshold is lowered such that the DRBG is forced to reseed
itself resonably often. Once it obtains the seed from a fully
initialized nonblocking pool, the reseed threshold is set to the value
required by SP800-90A.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The get_blocking_random_bytes API is broken because the wait can
be arbitrarily long (potentially forever) so there is no safe way
of calling it from within the kernel.
This patch replaces it with the new callback API which does not
have this problem.
The patch also removes the entropy buffer registered with the DRBG
handle in favor of stack variables to hold the seed data.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Replace the global -O0 compiler flag from the Makefile with GCC
pragmas to mark only the functions required to be compiled without
optimizations.
This patch also adds a comment describing the rationale for the
functions chosen to be compiled without optimizations.
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch creates a new invisible Kconfig option CRYPTO_RNG_DEFAULT
that simply selects the DRBG. This new option is then selected
by the IV generators.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds the stdrng module alias and increases the priority
to ensure that it is loaded in preference to other RNGs.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We currently do the IV seeding on the first givencrypt call in
order to conserve entropy. However, this does not work with
DRBG which cannot be called from interrupt context. In fact,
with DRBG we don't need to conserve entropy anyway. So this
patch moves the seeding into the init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We currently do the IV seeding on the first givencrypt call in
order to conserve entropy. However, this does not work with
DRBG which cannot be called from interrupt context. In fact,
with DRBG we don't need to conserve entropy anyway. So this
patch moves the seeding into the init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We currently do the IV seeding on the first givencrypt call in
order to conserve entropy. However, this does not work with
DRBG which cannot be called from interrupt context. In fact,
with DRBG we don't need to conserve entropy anyway. So this
patch moves the seeding into the init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We currently do the IV seeding on the first givencrypt call in
order to conserve entropy. However, this does not work with
DRBG which cannot be called from interrupt context. In fact,
with DRBG we don't need to conserve entropy anyway. So this
patch moves the seeding into the init function.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
draft-ietf-ipsecme-chacha20-poly1305 defines the use of ChaCha20/Poly1305 in
ESP. It uses additional four byte key material as a salt, which is then used
with an 8 byte IV to form the ChaCha20 nonce as defined in the RFC7539.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This AEAD uses a chacha20 ablkcipher and a poly1305 ahash to construct the
ChaCha20-Poly1305 AEAD as defined in RFC7539. It supports both synchronous and
asynchronous operations, even if we currently have no async chacha20 or poly1305
drivers.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Poly1305 is a fast message authenticator designed by Daniel J. Bernstein.
It is further defined in RFC7539 as a building block for the ChaCha20-Poly1305
AEAD for use in IETF protocols.
This is a portable C implementation of the algorithm without architecture
specific optimizations, based on public domain code by Daniel J. Bernstein and
Andrew Moon.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
We explicitly set the Initial block Counter by prepending it to the nonce in
Little Endian. The same test vector is used for both encryption and decryption,
ChaCha20 is a cipher XORing a keystream.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ChaCha20 is a high speed 256-bit key size stream cipher algorithm designed by
Daniel J. Bernstein. It is further specified in RFC7539 for use in IETF
protocols as a building block for the ChaCha20-Poly1305 AEAD.
This is a portable C implementation without any architecture specific
optimizations. It uses a 16-byte IV, which includes the 12-byte ChaCha20 nonce
prepended by the initial block counter. Some algorithms require an explicit
counter value, for example the mentioned AEAD construction.
Signed-off-by: Martin Willi <martin@strongswan.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On architectures where flush_dcache_page is not needed, we will
end up generating all the code up to the PageSlab call. This is
because PageSlab operates on a volatile pointer and thus cannot
be optimised away.
This patch works around this by checking whether flush_dcache_page
is needed before we call PageSlab which then allows PageSlab to be
compiled awy.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
No new code should be using the return value of crypto_unregister_alg
as it will become void soon.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch ensures that the tfm context always has enough extra
memory to ensure that it is aligned according to cra_alignment.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As it stands the only non-type safe functions left in the new
AEAD interface are the cra_init/cra_exit functions. It means
exposing the ugly __crypto_aead_cast to every AEAD implementor.
This patch adds type-safe init/exit functions to AEAD. Existing
algorithms are unaffected while new implementations can simply
fill in these two instead of cra_init/cra_exit.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This reverts commit f858c7bcca as
the algif_aead interface has been switched over to the new AEAD
interface.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The patch removes the use of timekeeping_valid_for_hres which is now
marked as internal for the time keeping subsystem. The jitterentropy
does not really require this verification as a coarse timer (when
random_get_entropy is absent) is discovered by the initialization test
of jent_entropy_init, which would cause the jitter rng to not load in
that case.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.
Note that the user-space interface now requires both input and
output to be of the same length, and both must include space for
the AD as well as the authentication tag.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch makes use of the new AEAD interface which uses a single
SG list instead of separate lists for the AD and plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On module unload we weren't unregistering the seqniv template,
thus leading to a crash the next time someone walks the template
list.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes a bug in the context size calculation where we
were still referring to the old cra_aead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the AD does not necessarily exist in the destination buffer
it must be copied along with the plain/cipher text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes a bug in the context size calculation where we
were still referring to the old cra_aead.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
As the AD does not necessarily exist in the destination buffer
it must be copied along with the plain text.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch adds some common IV generation code currently duplicated
by seqiv and echainiv. For example, the setkey and setauthsize
functions are completely identical.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch tries to preserve in-place processing in old_crypt as
various algorithms are optimised for in-place processing where
src == dst.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The CPU Jitter RNG provides a source of good entropy by
collecting CPU executing time jitter. The entropy in the CPU
execution time jitter is magnified by the CPU Jitter Random
Number Generator. The CPU Jitter Random Number Generator uses
the CPU execution timing jitter to generate a bit stream
which complies with different statistical measurements that
determine the bit stream is random.
The CPU Jitter Random Number Generator delivers entropy which
follows information theoretical requirements. Based on these
studies and the implementation, the caller can assume that
one bit of data extracted from the CPU Jitter Random Number
Generator holds one bit of entropy.
The CPU Jitter Random Number Generator provides a decentralized
source of entropy, i.e. every caller can operate on a private
state of the entropy pool.
The RNG does not have any dependencies on any other service
in the kernel. The RNG only needs a high-resolution time
stamp.
Further design details, the cryptographic assessment and
large array of test results are documented at
http://www.chronox.de/jent.html.
CC: Andreas Steffen <andreas.steffen@strongswan.org>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Sandy Harris <sandyinchina@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
During initialization, the DRBG now tries to allocate a handle of the
Jitter RNG. If such a Jitter RNG is available during seeding, the DRBG
pulls the required entropy/nonce string from get_random_bytes and
concatenates it with a string of equal size from the Jitter RNG. That
combined string is now the seed for the DRBG.
Written differently, the initial seed of the DRBG is now:
get_random_bytes(entropy/nonce) || jitterentropy (entropy/nonce)
If the Jitter RNG is not available, the DRBG only seeds from
get_random_bytes.
CC: Andreas Steffen <andreas.steffen@strongswan.org>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Sandy Harris <sandyinchina@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The async seeding operation is triggered during initalization right
after the first non-blocking seeding is completed. As required by the
asynchronous operation of random.c, a callback function is provided that
is triggered by random.c once entropy is available. That callback
function performs the actual seeding of the DRBG.
CC: Andreas Steffen <andreas.steffen@strongswan.org>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Sandy Harris <sandyinchina@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
In order to prepare for the addition of the asynchronous seeding call,
the invocation of seeding the DRBG is moved out into a helper function.
In addition, a block of memory is allocated during initialization time
that will be used as a scratchpad for obtaining entropy. That scratchpad
is used for the initial seeding operation as well as by the
asynchronous seeding call. The memory must be zeroized every time the
DRBG seeding call succeeds to avoid entropy data lingering in memory.
CC: Andreas Steffen <andreas.steffen@strongswan.org>
CC: Theodore Ts'o <tytso@mit.edu>
CC: Sandy Harris <sandyinchina@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
