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path: root/crypto/drbg.c
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2016-06-20crypto: drbg - fix an error code in drbg_init_sym_kernel()Dan Carpenter
We accidentally return PTR_ERR(NULL) which is success but we should return -ENOMEM. Fixes: 355912852115 ('crypto: drbg - use CTR AES instead of ECB AES') Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Acked-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-20crypto: drbg - fix semicolon.cocci warningsWu Fengguang
crypto/drbg.c:1637:39-40: Unneeded semicolon Remove unneeded semicolon. Generated by: scripts/coccinelle/misc/semicolon.cocci CC: Stephan Mueller <smueller@chronox.de> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-15crypto: drbg - avoid duplicate maintenance of keyStephan Mueller
The TFM object maintains the key for the CTR DRBG. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-15crypto: drbg - use full CTR AES for updateStephan Mueller
The CTR DRBG update function performs a full CTR AES operation including the XOR with "plaintext" data. Hence, remove the XOR from the code and use the CTR mode to do the XOR. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-15crypto: drbg - use aligned buffersStephan Mueller
Hardware cipher implementation may require aligned buffers. All buffers that potentially are processed with a cipher are now aligned. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-15crypto: drbg - use CTR AES instead of ECB AESStephan Mueller
The CTR DRBG derives its random data from the CTR that is encrypted with AES. This patch now changes the CTR DRBG implementation such that the CTR AES mode is employed. This allows the use of steamlined CTR AES implementation such as ctr-aes-aesni. Unfortunately there are the following subtile changes we need to apply when using the CTR AES mode: - the CTR mode increments the counter after the cipher operation, but the CTR DRBG requires the increment before the cipher op. Hence, the crypto_inc is applied to the counter (drbg->V) once it is recalculated. - the CTR mode wants to encrypt data, but the CTR DRBG is interested in the encrypted counter only. The full CTR mode is the XOR of the encrypted counter with the plaintext data. To access the encrypted counter, the patch uses a NULL data vector as plaintext to be "encrypted". Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-02crypto: drbg - reduce number of setkey callsStephan Mueller
The CTR DRBG code always set the key for each sym cipher invocation even though the key has not been changed. The patch ensures that the setkey is only invoked when a new key is generated by the DRBG. With this patch, the CTR DRBG performance increases by more than 150%. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-04-05crypto: drbg - set HMAC key only when alteredStephan Mueller
The HMAC implementation allows setting the HMAC key independently from the hashing operation. Therefore, the key only needs to be set when a new key is generated. This patch increases the speed of the HMAC DRBG by at least 35% depending on the use case. The patch is fully CAVS tested. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-01-25crypto: drbg - remove FIPS 140-2 continuous testStephan Mueller
The newly released FIPS 140-2 IG 9.8 specifies that for SP800-90A compliant DRBGs, the FIPS 140-2 continuous random number generator test is not required any more. This patch removes the test and all associated data structures. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-10crypto: drbg - constify drbg_state_ops structuresJulia Lawall
The drbg_state_ops structures are never modified, so declare them as const. Done with the help of Coccinelle. Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-06-11crypto: drbg - report backend_cra_name when allocation failsSergey Senozhatsky
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>
2015-06-10crypto: drbg - reseed often if seedsource is degradedStephan Mueller
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>
2015-06-10crypto: drbg - Use callback API for random readinessStephan Mueller
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>
2015-06-04crypto: drbg - Add stdrng alias and increase priorityHerbert Xu
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>
2015-05-27crypto: drbg - use Jitter RNG to obtain seedStephan Mueller
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>
2015-05-27crypto: drbg - add async seeding operationStephan Mueller
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>
2015-05-27crypto: drbg - prepare for async seedingStephan Mueller
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>
2015-04-23crypto: drbg - Remove FIPS ifdef from drbg_healthcheck_sanityHerbert Xu
This patch removes the unnecessary CRYPTO_FIPS ifdef from drbg_healthcheck_sanity so that the code always gets checked by the compiler. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Stephan Mueller <smueller@chronox.de>
2015-04-22crypto: drbg - Convert to new rng interfaceHerbert Xu
This patch converts the DRBG implementation to the new low-level rng interface. This allows us to get rid of struct drbg_gen by using the new RNG API instead. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Stephan Mueller <smueller@chronox.de>
2015-04-21crypto: drbg - Do not seed RNG in drbg_kcapi_initHerbert Xu
Initialising the RNG in drbg_kcapi_init is a waste of precious entropy because all users will immediately seed the RNG after the allocation. In fact, all users should seed the RNG before using it. So there is no point in doing the seeding in drbg_kcapi_init. This patch removes the initial seeding and the user must seed the RNG explicitly (as they all currently do). This patch also changes drbg_kcapi_reset to allow reseeding. That is, if you call it after a successful initial seeding, then it will not reset the internal state of the DRBG before mixing the new input and entropy. If you still wish to reset the internal state, you can always free the DRBG and allocate a new one. Finally this patch removes locking from drbg_uninstantiate because it's now only called from the destruction path which must not be executed in parallel with normal operations. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Stephan Mueller <smueller@chronox.de>
2015-04-21crypto: drbg - Initialise mutex in drbg_healthcheck_sanityHerbert Xu
As we moved the mutex init out of drbg_instantiate and into cra_init we need to explicitly initialise the mutex in drbg_healthcheck_sanity. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Acked-by: Stephan Mueller <smueller@chronox.de>
2015-04-21crypto: drbg - leave cipher handles operationalStephan Mueller
As the DRBG does not operate on shadow copies of the DRBG instance any more, the cipher handles only need to be allocated once during initalization time and deallocated during uninstantiate time. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-04-21crypto: drbg - replace spinlock with mutexStephan Mueller
The creation of a shadow copy is intended to only hold a short term lock. But the drawback is that parallel users have a very similar DRBG state which only differs by a high-resolution time stamp. The DRBG will now hold a long term lock. Therefore, the lock is changed to a mutex which implies that the DRBG can only be used in process context. The lock now guards the instantiation as well as the entire DRBG generation operation. Therefore, multiple callers are fully serialized when generating a random number. As the locking is changed to use a long-term lock to avoid such similar DRBG states, the entire creation and maintenance of a shadow copy can be removed. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-04-21crypto: drbg - fix drbg_generate return val checkStephan Mueller
The drbg_generate returns 0 in success case. That means that drbg_generate_long will always only generate drbg_max_request_bytes at most. Longer requests will be truncated to drbg_max_request_bytes. Reported-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-04-21cryoto: drbg - clear all temporary memoryStephan Mueller
The buffer uses for temporary data must be cleared entirely. In AES192 the used buffer is drbg_statelen(drbg) + drbg_blocklen(drbg) as documented in the comment above drbg_ctr_df. This patch ensures that the temp buffer is completely wiped. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-09crypto: rng - RNGs must return 0 in success caseStephan Mueller
Change the RNGs to always return 0 in success case. This patch ensures that seqiv.c works with RNGs other than krng. seqiv expects that any return code other than 0 is an error. Without the patch, rfc4106(gcm(aes)) will not work when using a DRBG or an ANSI X9.31 RNG. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-04crypto: drbg - remove superflowous memsetsStephan Mueller
The DRBG code contains memset(0) calls to initialize a varaible that are not necessary as the variable is always overwritten by the processing. This patch increases the CTR and Hash DRBGs by about 5%. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-03-04crypto: drbg - use single block cipher APIStephan Mueller
The CTR DRBG only encrypts one single block at a time. Thus, use the single block crypto API to avoid additional overhead from the block chaining modes. With the patch, the speed of the DRBG increases between 30% and 40%. The DRBG still passes the CTR DRBG CAVS test. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-01-05Revert "crypto: drbg - use memzero_explicit() for clearing sensitive data"Herbert Xu
This reverts commit 421d82f5b3e75f94e31875e37d45cdf6a557c120. None of the data zeroed are on the stack so the compiler cannot optimise them away. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-12-22crypto: drbg - panic on continuous self test errorStephan Mueller
This patch adds a panic if the FIPS 140-2 self test error failed. Note, that entire code is only executed with fips_enabled (i.e. when the kernel is booted with fips=1. It is therefore not executed for 99.9% of all user base. As mathematically such failure cannot occur, this panic should never be triggered. But to comply with NISTs current requirements, an endless loop must be replaced with the panic. When the new version of FIPS 140 will be released, this entire continuous self test function will be ripped out as it will not be needed any more. This patch is functionally equivalent as implemented in ansi_cprng.c and drivers/char/random.c. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-27crypto: drbg - use memzero_explicit() for clearing sensitive dataNickolaus Woodruff
Compiler dead store optimization can sometimes remove final calls to memset() used to clear sensitive data at the end of a function. Replace trailing memset() calls with memzero_explicit() to preclude unwanted removal. Signed-off-by: Nickolaus Woodruff <nickolauswoodruff@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-26crypto: drbg - use MODULE_ALIAS_CRYPTOStephan Mueller
Use the crypto- prefix for the DRBG implementations. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-11-10crypto: drbg - add MODULE_ALIAS for all DRBG typesStephan Mueller
The kernel module drbg.ko is currently not loaded automatically when a DRBG is requested by a consumer. This is due to missing MODULE_ALIAS flags for each of the implemented DRBG types. This patch adds aliases for each of the 22 defined DRBGs. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-10-24crypto: drbg - use crypto_incStephan Mueller
The DRBG internal buffer addition function is replaced with crypto_inc when a buffer is to be incremented by one. The function drbg_add_buf is moved to the CONFIG_CRYPTO_DRBG_HASH ifdef area as it is now only needed for the Hash DRBG. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-09-05Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Herbert Xu
Merging the crypto tree for 3.17 in order to resolve the conflict on the 32-bit DRBG overflow fix.
2014-09-05crypto: drbg - remove check for uninitialized DRBG handleStephan Mueller
The drbg_healthcheck() contained a test to call the DRBG with an uninitialized DRBG cipher handle. As this is an inappropriate use of the kernel crypto API to try to generate random numbers before initialization, checks verifying for an initialized DRBG have been removed in previous patches. Now, the drbg_healthcheck test must also be removed. Changes V2: Added patch marker to email subject line. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-26crypto: drbg - fix sparse warning for cpu_to_be[32|64]Stephan Mueller
The sparse tool complained that the cpu_to_be[32|64] functions return __be[32|64] instead of __u32 or __u64. The patch replaces the __u32 and __u64 with __be32 and __be64. 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>
2014-08-25crypto: drbg - remove unnecessary sanity check for shadow stateStephan Mueller
During creation of the DRBG shadow state, it is ensured that the DRBG state structure is already allocated. Thus, a sanity check for verifying that the structure is allocated is removed. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - remove configuration of fixed valuesStephan Mueller
SP800-90A mandates several hard-coded values. The old drbg_cores allows the setting of these values per DRBG implementation. However, due to the hard requirement of SP800-90A, these values are now returned globally for each DRBG. The ability to set such values per DRBG is therefore removed. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - remove unnecessary sanity checksStephan Mueller
The drbg_make_shadow function contains sanity checks which are not needed as the function is invoked at times where it is ensured that the checked-for variables are available. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - use kmalloc instead of kzalloc for V and CStephan Mueller
When allocating V, C, the zeroization is only needed when allocating a new instance of the DRBG, i.e. when performing an initial seeding. For all other allocations, the memcpy implemented in drbg_copy_drbg ensures that the memory is filled with the correct information. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - remove superflowous memset(0)Stephan Mueller
Remove memset(0) which is not needed due to the kzalloc of the memory. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - remove superflowous checksStephan Mueller
The crypto_init and crypto_fini functions are always implemented. Thus, there is no need for a protecting check. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - kzfree does not need a check for NULL pointerStephan Mueller
The kzfree function already performs the NULL pointer check. Therefore, the DRBG code does not need to implement such check. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-25crypto: drbg - replace int2byte with cpu_to_beStephan Mueller
The DRBG requires the conversion of an integer into a string representation of that integer. The previous implementation converted the given integer byte-wise. However, the kernel offers the cpu_to_be function which already re-arranges the memory representation of an integer such that it applies when interpreting the same memory as character string. The change therefore uses an integer-cast / union of the target character array together with the cpu_to_be function to convert an integer into its string representation. Tests show that the Hash and CTR DRBG implementations (the HMAC DRBG does not require such conversion) is about 10% faster (or requires less computing power, respectively). Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-08-01crypto: drbg - fix failure of generating multiple of 2**16 bytesStephan Mueller
The function drbg_generate_long slices the request into 2**16 byte or smaller chunks. However, the loop, however invokes the random number generation function with zero bytes when the request size is a multiple of 2**16 bytes. The fix prevents zero bytes requests. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-10crypto: drbg - drbg_exit() can be staticFengguang Wu
CC: Stephan Mueller <smueller@chronox.de> Signed-off-by: Fengguang Wu <fengguang.wu@intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-08crypto: drbg - HMAC-SHA1 DRBG has crypto strength of 128 bitsStephan Mueller
The patch corrects the security strength of the HMAC-SHA1 DRBG to 128 bits. This strength defines the size of the seed required for the DRBG. Thus, the patch lowers the seeding requirement from 256 bits to 128 bits for HMAC-SHA1. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-08crypto: drbg - Mix a time stamp into DRBG stateStephan Mueller
The current locking approach of the DRBG tries to keep the protected code paths very minimal. It is therefore possible that two threads query one DRBG instance at the same time. When thread A requests random numbers, a shadow copy of the DRBG state is created upon which the request for A is processed. After finishing the state for A's request is merged back into the DRBG state. If now thread B requests random numbers from the same DRBG after the request for thread A is received, but before A's shadow state is merged back, the random numbers for B will be identical to the ones for A. Please note that the time window is very small for this scenario. To prevent that there is even a theoretical chance for thread A and B having the same DRBG state, the current time stamp is provided as additional information string for each new request. The addition of the time stamp as additional information string implies that now all generate functions must be capable to process a linked list with additional information strings instead of a scalar. CC: Rafael Aquini <aquini@redhat.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2014-07-08crypto: drbg - Select correct DRBG core for stdrngStephan Mueller
When the DRBG is initialized, the core is looked up using the DRBG name. The name that can be used for the lookup is registered in cra_driver_name. The cra_name value contains stdrng. Thus, the lookup code must use crypto_tfm_alg_driver_name to obtain the precise DRBG name and select the correct DRBG. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>