Currently we only allow /dev/random and /dev/hwrng as host input
for <rng><backend model='random'/> device. This was added after
various upstream discussions in commit 4932ef45

However this restriction has generated quite a few complaints over
the years, so a new discussion was initiated:

http://www.redhat.com/archives/libvir-list/2016-April/msg00987.html

Several people suggested removing the restriction, and nobody really
spoke up to defend it. So this patch drops the path restriction
entirely

https://bugzilla.redhat.com/show_bug.cgi?id=1074464
(cherry picked from commit 67f2b727)

Per-domain directories were introduced in order to be able to
completely separate security labels for each domain (commit
f1f68ca3).  However when the domain
name is long (let's say a ridiculous 110 characters), we cannot
connect to the monitor socket because on length of UNIX socket address
is limited.  In order to get around this, let's shorten it in similar
fashion and in order to avoid conflicts, throw in an ID there as well.
Also save that into the status XML and load the old status XMLs
properly (to clean up after older domains).  That way we can change it
in the future.

The shortening can be seen in qemuxml2argv tests, for example in the
hugepages-pages2 case.
Signed-off-by: NMartin Kletzander <mkletzan@redhat.com>

The -uuid arg was added in QEMU 0.10.0, so the QEMU driver can
assume it is always available.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

The -name arg was added in QEMU 0.9.1, so the QEMU driver can
assume it is always available.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Back in

  commit bd6c46fa
  Author: Juerg Haefliger <juerg.haefliger@hp.com>
  Date:   Mon Jan 31 06:42:57 2011 -0500

    tests: handle backspace-newline pairs in test input files

all the test argv files were line wrapped so that the args
were less than 80 characters.

The way the line wrapping was done turns out to be quite
undesirable, because it often leaves multiple parameters
on the same line. If we later need to add or remove
individual parameters, then it leaves us having to redo
line wrapping.

This commit changes the line wrapping so that every
single "-param value" is one its own new line. If the
"value" is still too long, then we break on ',' or ':'
or ' ' as needed.

This means that when we come to add / remove parameters
from the test files line, the patch diffs will only
ever show a single line added/removed which will greatly
simplify review work.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>

Libvirt didn't prefix the random number generator backend object alias
with any string thus the device alias and object alias were identical.

To avoid possible problems, rename the alias for the backend object and
tweak tests to comply with the change.
Signed-off-by: NLuyao Huang <lhuang@redhat.com>
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>

On my machine, a guest fails to boot if it has a sound card, but not
graphical device/display is configured, because pulseaudio fails to
initialize since it can't access $HOME.

A workaround is removing the audio device, however on ARM boards there
isn't any option to do that, so -nographic always fails.

Set QEMU_AUDIO_DRV=none if no <graphics> are configured. Unfortunately
this has massive test suite fallout.

Add a qemu.conf parameter nographics_allow_host_audio, that if enabled
will pass through QEMU_AUDIO_DRV from sysconfig (similar to
vnc_allow_host_audio)

Qemu's implementation of virtio RNG supports rate limiting of the
entropy used. This patch exposes the option to tune this functionality.

This patch is based on qemu commit 904d6f588063fb5ad2b61998acdf1e73fb4

The rate limiting is exported in the XML as:
<devices>
  ...
  <rng model='virtio'>
    <rate bytes='123' period='1234'/>
    <backend model='random'/>
  </rng>
  ...

There is some controversy[1] on the qemu list on whether qemu should
have ever allowed arbitrary file name passthrough, or whether it
should be restricted to JUST /dev/random and /dev/hwrng.  It is
always easier to add support for additional filenames than it is
to remove support for something once released, so this patch
restricts libvirt 1.0.3 (where the virtio-random backend was first
supported) to just the two uncontroversial names, letting us defer
to a later date any decision on whether supporting arbitrary files
makes sense. Additionally, since qemu 1.4 does NOT support
/dev/fdset/nnn fd passthrough for the backend, limiting to just
two known names means that we don't get tempted to try fd
passthrough where it won't work.

[1]https://lists.gnu.org/archive/html/qemu-devel/2013-03/threads.html#00023

* src/conf/domain_conf.c (virDomainRNGDefParseXML): Only allow
/dev/random and /dev/hwrng.
* docs/schemas/domaincommon.rng: Flag invalid files.
* docs/formatdomain.html.in (elementsRng): Document this.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.args:
Update test to match.
* tests/qemuxml2argvdata/qemuxml2argv-virtio-rng-random.xml:
Likewise.

Users may want to specify XML entities in paths to devices. Ensure they
are parsed and used properly.

Adds XML parsing and qemu commandline tests for the VirtIO RNG device
support.