class JitterentropyCollector
Defined at line 27 of file ../../zircon/kernel/lib/crypto/include/lib/crypto/entropy/jitterentropy_collector.h
An implementation of crypto::entropy::Collector that uses jitterentropy as
its entropy source. Ultimately, the entropy is derived from variations in
CPU timing, when various code blocks are exercised.
TODO(andrewkrieger): Document jitterentropy better for Zircon, then link to
that documentation here.
Public Methods
zx_status_t GetInstance (Collector ** ptr)Gets the global JitterentropyCollector instance. Returns
ZX_ERR_NOT_SUPPORTED if jitterentropy is not supported (usually because
the system clock is not available or not suitable).
This function must be called once in a single-threaded context to
initialize the JitterentropyCollector instance. After one successful call
(typically during boot), it's safe to call this function from multiple
threads, and to access the JitterentropyCollector instance from multiple
threads. The JitterentropyCollector::DrawEntropy method is internally
guarded by a mutex, so it's safe to call from multiple threads but it may
block.
Defined at line 34 of file ../../zircon/kernel/lib/crypto/entropy/jitterentropy_collector.cc
size_t DrawEntropy (uint8_t * buf, size_t len)Inherited from Collector; see comments there.
Note that this method internally uses a mutex to prevent multiple
accesses. It is safe to call this method from multiple threads, but it
may block.
TODO(andrewkrieger): Determine what level of thread safety is needed for
RNG reseeding, and support it more uniformly (e.g. have a thread safety
contract for Collector::DrawEntropy, obeyed by all implementations).
Defined at line 94 of file ../../zircon/kernel/lib/crypto/entropy/jitterentropy_collector.cc
Friends
class Access