POWER8 has hardware transactional memory, which glibc uses to implement
locks. In some cases, taking a lock begins a transaction, wrapping
arbitrary user code (!) until the lock is released. If the transaction
is aborted, everything rewinds and glibc tries again with some other
implementation.
The kernel will abort the transaction in a variety of cases. Notably, on
a syscall, the transaction aborts and the syscall *does not happen*.
https://www.kernel.org/doc/Documentation/powerpc/transactional_memory.txt
Yet, for some reason, although the relevant change does appear to be in
the kernel, the transaction is being rewound with getrandom happening
anyway. This does not work very well.
Instead, only guard the DRBG access with the lock, not CRYPTO_sysrand.
This lock is only used to protect the DRBG from the destructor that
zeros everything.
Change-Id: Ied8350f1e808a09300651de4200c7b0d07b3a158
Reviewed-on: https://boringssl-review.googlesource.com/16985
Commit-Queue: David Benjamin <davidben@google.com>
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: Adam Langley <agl@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Without this, trying to trigger the CRNGT on a system with RDRAND won't
work.
Change-Id: I0658a1f045620a2800df36277f67305bc0efff8b
Reviewed-on: https://boringssl-review.googlesource.com/16766
Reviewed-by: Adam Langley <agl@google.com>
FIPS requires that the CTR-DRBG state be zeroed on process exit, however
destructors for thread-local data aren't called when the process exits.
This change maintains a linked-list of thread-local state which is
walked on exit to zero each thread's PRNG state. Any concurrently
running threads block until the process finishes exiting.
Change-Id: Ie5dc18e1bb2941a569d8b309411cf20c9bdf52ef
Reviewed-on: https://boringssl-review.googlesource.com/16764
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
Change-Id: Iab7a738a8981de7c56d1585050e78699cb876dab
Reviewed-on: https://boringssl-review.googlesource.com/16467
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
This change causes FIPS mode to use RDRAND in preference to the kernel's
entropy pool. This prevents issues where the ioctl that we have to do
when getrandom isn't supported transiently reports that the pool is
“empty” and causes us to block.
Change-Id: Iad50e443d88b168bf0b85fe1e91e153d79ab3703
Reviewed-on: https://boringssl-review.googlesource.com/16466
Commit-Queue: David Benjamin <davidben@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
OPENSSL_ia32cap_addr avoids any relocations within the module, at the
cost of a runtime TEXTREL, which causes problems in some cases.
(Notably, if someone links us into a binary which uses the GCC "ifunc"
attribute, the loader crashes.)
Fix C references of OPENSSL_ia32cap_addr with a function. This is
analogous to the BSS getters. A follow-up commit will fix perlasm with a
different scheme which avoids calling into a function (clobbering
registers and complicating unwind directives.)
Change-Id: I09d6cda4cec35b693e16b5387611167da8c7a6de
Reviewed-on: https://boringssl-review.googlesource.com/15525
Reviewed-by: Adam Langley <agl@google.com>
Support for platforms that we don't support FIPS on doesn't need to be
in the module. Also, functions for dealing with whether fork-unsafe
buffering is enabled are left out because they aren't implementing any
cryptography and they use global r/w state, making their inclusion
painful.
Change-Id: I71a0123db6f5449e9dfc7ec7dea0944428e661aa
Reviewed-on: https://boringssl-review.googlesource.com/15084
Reviewed-by: Adam Langley <agl@google.com>
