VIORND(4) FreeBSD Kernel Interfaces Manual VIORND(4)
NAME
viornd - VirtIO random number device
SYNOPSIS
viornd* at virtio? flags 0x00
DESCRIPTION
The viornd driver provides a virtual random number generator using a
virtio(4) entropy device provided by QEMU 1.3 and later, and possibly by
other hypervisors.
As there is currently no way for viornd to determine how much entropy is
needed, the second byte of the flags value can be used to configure how
often it should request more entropy from the host. If the second lowest
byte of the flags has a value from 1 to 15, viornd will ask for 16 bytes
of entropy every 15 * (1 << value) seconds. For example, flags == 0x100
means an interval of 30 seconds, 0x500 means 8 minutes, 0xa00 means 256
minutes, and 0xf00 means about 6 days. For flags == 0, a default value
will be used (currently 8 minutes). If the bit 0x1000 is set in the
flags, viornd will only request entropy from the host once during system
boot.
SEE ALSO
intro(4), virtio(4)
HISTORY
The viornd driver first appeared in OpenBSD 5.5.
AUTHORS
The viornd driver was written by Stefan Fritsch <
[email protected]>.
FreeBSD 14.1-RELEASE-p8 February 17, 2015 FreeBSD 14.1-RELEASE-p8