Summary

Draw from the kernel's CPRNG.

Declaration

#include <zircon/syscalls.h>
void zx_cprng_draw(void* buffer, size_t buffer_size);

Description

zx_cprng_draw() draws random bytes from the kernel CPRNG. This data should be suitable for cryptographic applications.

Clients that require a large volume of randomness should consider using these bytes to seed a user-space random number generator for better performance. As always, test the actual latency of your call site before optimizing.

Rights

None.

Notes

zx_cprng_draw() terminates the calling process if buffer is not a valid userspace pointer.

There are no other error conditions. If its arguments are valid, zx_cprng_draw() will succeed.

See also

• zx_cprng_add_entropy()