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2021-09-17crypto: drbg - Fix unused value warning in drbg_healthcheck_sanity()Tim Gardner1-1/+1
Coverity warns uf an unused value: CID 44865 (#2 of 2): Unused value (UNUSED_VALUE) assigned_value: Assigning value -14 to ret here, but that stored value is overwritten before it can be used. 2006 int ret = -EFAULT; ... value_overwrite: Overwriting previous write to ret with value from drbg_seed(drbg, &addtl, false). 2052 ret = drbg_seed(drbg, &addtl, false); Fix this by removing the variable initializer. Cc: Herbert Xu <herbert@gondor.apana.org.au> Cc: "David S. Miller" <davem@davemloft.net> Cc: linux-crypto@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Tim Gardner <tim.gardner@canonical.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-05-28crypto: DRBG - switch to HMAC SHA512 DRBG as default DRBGStephan Müller1-6/+6
The default DRBG is the one that has the highest priority. The priority is defined based on the order of the list drbg_cores[] where the highest priority is given to the last entry by drbg_fill_array. With this patch the default DRBG is switched from HMAC SHA256 to HMAC SHA512 to support compliance with SP800-90B and SP800-90C (current draft). The user of the crypto API is completely unaffected by the change. Signed-off-by: Stephan Mueller <smueller@chronox.de> Acked-by: simo Sorce <simo@redhat.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2021-01-03crypto: remove cipher routines from public crypto APIArd Biesheuvel1-0/+2
The cipher routines in the crypto API are mostly intended for templates implementing skcipher modes generically in software, and shouldn't be used outside of the crypto subsystem. So move the prototypes and all related definitions to a new header file under include/crypto/internal. Also, let's use the new module namespace feature to move the symbol exports into a new namespace CRYPTO_INTERNAL. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Acked-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-08-24treewide: Use fallthrough pseudo-keywordGustavo A. R. Silva1-1/+1
Replace the existing /* fall through */ comments and its variants with the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary fall-through markings when it is the case. [1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-07mm, treewide: rename kzfree() to kfree_sensitive()Waiman Long1-5/+5
As said by Linus: A symmetric naming is only helpful if it implies symmetries in use. Otherwise it's actively misleading. In "kzalloc()", the z is meaningful and an important part of what the caller wants. In "kzfree()", the z is actively detrimental, because maybe in the future we really _might_ want to use that "memfill(0xdeadbeef)" or something. The "zero" part of the interface isn't even _relevant_. The main reason that kzfree() exists is to clear sensitive information that should not be leaked to other future users of the same memory objects. Rename kzfree() to kfree_sensitive() to follow the example of the recently added kvfree_sensitive() and make the intention of the API more explicit. In addition, memzero_explicit() is used to clear the memory to make sure that it won't get optimized away by the compiler. The renaming is done by using the command sequence: git grep -w --name-only kzfree |\ xargs sed -i 's/kzfree/kfree_sensitive/' followed by some editing of the kfree_sensitive() kerneldoc and adding a kzfree backward compatibility macro in slab.h. [akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h] [akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more] Suggested-by: Joe Perches <joe@perches.com> Signed-off-by: Waiman Long <longman@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: David Howells <dhowells@redhat.com> Acked-by: Michal Hocko <mhocko@suse.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> Cc: James Morris <jmorris@namei.org> Cc: "Serge E. Hallyn" <serge@hallyn.com> Cc: Joe Perches <joe@perches.com> Cc: Matthew Wilcox <willy@infradead.org> Cc: David Rientjes <rientjes@google.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "Jason A . Donenfeld" <Jason@zx2c4.com> Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-15crypto: drbg - always try to free Jitter RNG instanceStephan Müller1-2/+4
The Jitter RNG is unconditionally allocated as a seed source follwoing the patch 97f2650e5040. Thus, the instance must always be deallocated. Reported-by: syzbot+2e635807decef724a1fa@syzkaller.appspotmail.com Fixes: 97f2650e5040 ("crypto: drbg - always seeded with SP800-90B ...") Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-05-08crypto: drbg - fix error return code in drbg_alloc_state()Wei Yongjun1-1/+3
Fix to return negative error code -ENOMEM from the kzalloc error handling case instead of 0, as done elsewhere in this function. Reported-by: Xiumei Mu <xmu@redhat.com> Fixes: db07cd26ac6a ("crypto: drbg - add FIPS 140-2 CTRNG for noise source") Cc: <stable@vger.kernel.org> Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com> Reviewed-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-04-24crypto: drbg - always seeded with SP800-90B compliant noise sourceStephan Müller1-7/+19
As the Jitter RNG provides an SP800-90B compliant noise source, use this noise source always for the (re)seeding of the DRBG. To make sure the DRBG is always properly seeded, the reseed threshold is reduced to 1<<20 generate operations. The Jitter RNG may report health test failures. Such health test failures are treated as transient as follows. The DRBG will not reseed from the Jitter RNG (but from get_random_bytes) in case of a health test failure. Though, it produces the requested random number. The Jitter RNG has a failure counter where at most 1024 consecutive resets due to a health test failure are considered as a transient error. If more consecutive resets are required, the Jitter RNG will return a permanent error which is returned to the caller by the DRBG. With this approach, the worst case reseed threshold is significantly lower than mandated by SP800-90A in order to seed with an SP800-90B noise source: the DRBG has a reseed threshold of 2^20 * 1024 = 2^30 generate requests. Yet, in case of a transient Jitter RNG health test failure, the DRBG is seeded with the data obtained from get_random_bytes. However, if the Jitter RNG fails during the initial seeding operation even due to a health test error, the DRBG will send an error to the caller because at that time, the DRBG has received no seed that is SP800-90B compliant. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-23crypto: drbg - add FIPS 140-2 CTRNG for noise sourceStephan Mueller1-3/+91
FIPS 140-2 section 4.9.2 requires a continuous self test of the noise source. Up to kernel 4.8 drivers/char/random.c provided this continuous self test. Afterwards it was moved to a location that is inconsistent with the FIPS 140-2 requirements. The relevant patch was e192be9d9a30555aae2ca1dc3aad37cba484cd4a . Thus, the FIPS 140-2 CTRNG is added to the DRBG when it obtains the seed. This patch resurrects the function drbg_fips_continous_test that existed some time ago and applies it to the noise sources. The patch that removed the drbg_fips_continous_test was b3614763059b82c26bdd02ffcb1c016c1132aad0 . The Jitter RNG implements its own FIPS 140-2 self test and thus does not need to be subjected to the test in the DRBG. The patch contains a tiny fix to ensure proper zeroization in case of an error during the Jitter RNG data gathering. Signed-off-by: Stephan Mueller <smueller@chronox.de> Reviewed-by: Yann Droneaud <ydroneaud@opteya.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25crypto: shash - remove shash_desc::flagsEric Biggers1-1/+0
The flags field in 'struct shash_desc' never actually does anything. The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP. However, no shash algorithm ever sleeps, making this flag a no-op. With this being the case, inevitably some users who can't sleep wrongly pass MAY_SLEEP. These would all need to be fixed if any shash algorithm actually started sleeping. For example, the shash_ahash_*() functions, which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP from the ahash API to the shash API. However, the shash functions are called under kmap_atomic(), so actually they're assumed to never sleep. Even if it turns out that some users do need preemption points while hashing large buffers, we could easily provide a helper function crypto_shash_update_large() which divides the data into smaller chunks and calls crypto_shash_update() and cond_resched() for each chunk. It's not necessary to have a flag in 'struct shash_desc', nor is it necessary to make individual shash algorithms aware of this at all. Therefore, remove shash_desc::flags, and document that the crypto_shash_*() functions can be called from any context. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-18crypto: run initcalls for generic implementations earlierEric Biggers1-1/+1
Use subsys_initcall for registration of all templates and generic algorithm implementations, rather than module_init. Then change cryptomgr to use arch_initcall, to place it before the subsys_initcalls. This is needed so that when both a generic and optimized implementation of an algorithm are built into the kernel (not loadable modules), the generic implementation is registered before the optimized one. Otherwise, the self-tests for the optimized implementation are unable to allocate the generic implementation for the new comparison fuzz tests. Note that on arm, a side effect of this change is that self-tests for generic implementations may run before the unaligned access handler has been installed. So, unaligned accesses will crash the kernel. This is arguably a good thing as it makes it easier to detect that type of bug. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03crypto: drbg - in-place cipher operation for CTRStephan Müller1-20/+14
The cipher implementations of the kernel crypto API favor in-place cipher operations. Thus, switch the CTR cipher operation in the DRBG to perform in-place operations. This is implemented by using the output buffer as input buffer and zeroizing it before the cipher operation to implement a CTR encryption of a NULL buffer. The speed improvement is quite visibile with the following comparison using the LRNG implementation. Without the patch set: 16 bytes| 12.267661 MB/s| 61338304 bytes | 5000000213 ns 32 bytes| 23.603770 MB/s| 118018848 bytes | 5000000073 ns 64 bytes| 46.732262 MB/s| 233661312 bytes | 5000000241 ns 128 bytes| 90.038042 MB/s| 450190208 bytes | 5000000244 ns 256 bytes| 160.399616 MB/s| 801998080 bytes | 5000000393 ns 512 bytes| 259.878400 MB/s| 1299392000 bytes | 5000001675 ns 1024 bytes| 386.050662 MB/s| 1930253312 bytes | 5000001661 ns 2048 bytes| 493.641728 MB/s| 2468208640 bytes | 5000001598 ns 4096 bytes| 581.835981 MB/s| 2909179904 bytes | 5000003426 ns With the patch set: 16 bytes | 17.051142 MB/s | 85255712 bytes | 5000000854 ns 32 bytes | 32.695898 MB/s | 163479488 bytes | 5000000544 ns 64 bytes | 64.490739 MB/s | 322453696 bytes | 5000000954 ns 128 bytes | 123.285043 MB/s | 616425216 bytes | 5000000201 ns 256 bytes | 233.434573 MB/s | 1167172864 bytes | 5000000573 ns 512 bytes | 384.405197 MB/s | 1922025984 bytes | 5000000671 ns 1024 bytes | 566.313370 MB/s | 2831566848 bytes | 5000001080 ns 2048 bytes | 744.518042 MB/s | 3722590208 bytes | 5000000926 ns 4096 bytes | 867.501670 MB/s | 4337508352 bytes | 5000002181 ns Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-20crypto: drbg - eliminate constant reinitialization of SGLStephan Mueller1-4/+7
The CTR DRBG requires two SGLs pointing to input/output buffers for the CTR AES operation. The used SGLs always have only one entry. Thus, the SGL can be initialized during allocation time, preventing a re-initialization of the SGLs during each call. The performance is increased by about 1 to 3 percent depending on the size of the requested buffer size. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-04-20crypto: drbg - set freed buffers to NULLStephan Mueller1-0/+2
During freeing of the internal buffers used by the DRBG, set the pointer to NULL. It is possible that the context with the freed buffers is reused. In case of an error during initialization where the pointers do not yet point to allocated memory, the NULL value prevents a double free. Cc: stable@vger.kernel.org Fixes: 3cfc3b9721123 ("crypto: drbg - use aligned buffers") Signed-off-by: Stephan Mueller <smueller@chronox.de> Reported-by: syzbot+75397ee3df5c70164154@syzkaller.appspotmail.com Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03crypto: drbg - move to generic async completionGilad Ben-Yossef1-27/+9
DRBG is starting an async. crypto op and waiting for it complete. Move it over to generic code doing the same. The code now also passes CRYPTO_TFM_REQ_MAY_SLEEP flag indicating crypto request memory allocation may use GFP_KERNEL which should be perfectly fine as the code is obviously sleeping for the completion of the request any way. Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-09-20crypto: drbg - fix freeing of resourcesStephan Mueller1-4/+4
During the change to use aligned buffers, the deallocation code path was not updated correctly. The current code tries to free the aligned buffer pointer and not the original buffer pointer as it is supposed to. Thus, the code is updated to free the original buffer pointer and set the aligned buffer pointer that is used throughout the code to NULL. Fixes: 3cfc3b9721123 ("crypto: drbg - use aligned buffers") CC: <stable@vger.kernel.org> CC: 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>
2017-06-22crypto: drbg - Fixes panic in wait_for_completion callStephan Mueller1-0/+1
Initialise ctr_completion variable before use. Cc: <stable@vger.kernel.org> Signed-off-by: Harsh Jain <harshjain.prof@gmail.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-05-23crypto: drbg - wait for crypto op not signal safeGilad Ben-Yossef1-3/+2
drbg_kcapi_sym_ctr() was using wait_for_completion_interruptible() to wait for completion of async crypto op but if a signal occurs it may return before DMA ops of HW crypto provider finish, thus corrupting the output buffer. Resolve this by using wait_for_completion() instead. Reported-by: Eric Biggers <ebiggers3@gmail.com> Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com> CC: stable@vger.kernel.org Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-03-24crypto: DRBG - initialize SGL only onceStephan Mueller1-3/+2
An SGL to be initialized only once even when its buffers are written to several times. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Herbert Xu1-5/+24
Merge the crypto tree to pull in chelsio chcr fix.
2016-11-30crypto: drbg - prevent invalid SG mappingsStephan Mueller1-5/+24
When using SGs, only heap memory (memory that is valid as per virt_addr_valid) is allowed to be referenced. The CTR DRBG used to reference the caller-provided memory directly in an SG. In case the caller provided stack memory pointers, the SG mapping is not considered to be valid. In some cases, this would even cause a paging fault. The change adds a new scratch buffer that is used unconditionally to catch the cases where the caller-provided buffer is not suitable for use in an SG. The crypto operation of the CTR DRBG produces its output with that scratch buffer and finally copies the content of the scratch buffer to the caller's buffer. The scratch buffer is allocated during allocation time of the CTR DRBG as its access is protected with the DRBG mutex. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-21crypto: drbg - advance output buffer pointerStephan Mueller1-0/+1
The CTR DRBG segments the number of random bytes to be generated into 128 byte blocks. The current code misses the advancement of the output buffer pointer when the requestor asks for more than 128 bytes of data. In this case, the next 128 byte block of random numbers is copied to the beginning of the output buffer again. This implies that only the first 128 bytes of the output buffer would ever be filled. The patch adds the advancement of the buffer pointer to fill the entire buffer. Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-08-24crypto: drbg - fix error return codeWei Yongjun1-5/+11
Fix to return a negative error code from the error handling case instead of 0. Signed-off-by: Wei Yongjun <weiyj.lk@gmail.com> Acked-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-08-16crypto: drbg - do not call drbg_instantiate in healt testStephan Mueller1-11/+4
When calling the DRBG health test in FIPS mode, the Jitter RNG is not yet present in the kernel crypto API which will cause the instantiation to fail and thus the health test to fail. As the health tests cover the enforcement of various thresholds, invoke the functions that are supposed to enforce the thresholds directly. This patch also saves precious seed. Reported-by: Tapas Sarangi <TSarangi@trustwave.com> Signed-off-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-06-20crypto: drbg - fix an error code in drbg_init_sym_kernel()Dan Carpenter1-1/+1
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 Fengguang1-1/+1
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 Mueller1-2/+1
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 Mueller1-17/+13
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 Mueller1-20/+24
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 Mueller1-54/+139
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 Mueller1-9/+24
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 Mueller1-14/+25
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 Mueller1-64/+0
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 Lawall1-3/+3
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 Senozhatsky1-2/+4
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 Mueller1-1/+11
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 Mueller1-91/+126
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 Xu1-1/+2
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 Mueller1-7/+45
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 Mueller1-0/+24
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 Mueller1-27/+54
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 Xu1-4/+0
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 Xu1-69/+54
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 Xu1-48/+55
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 Xu1-0/+2
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 Mueller1-8/+4
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 Mueller1-119/+25
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 Mueller1-7/+7
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 Mueller1-1/+1
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 Mueller1-1/+6
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>