Configure package manager to use 127.0.0.1:8082 as proxy instead of
"magic" IP intercepted later. The listen on this port and whenever
new connection arrives, spawn qubes.UpdatesProxy service call (to
default target domain - subject to configuration in dom0) and connect
its stdin/out to the local TCP connection. This part use systemd.socket
unit in case of systemd, and ncat --exec otherwise.
On the other end - in target domain - simply pass stdin/out to updates
proxy (tinyproxy) running locally.
It's important to _not_ configure the same VM to both be updates proxy and
use it. In practice such configuration makes little sense - if VM can
access network (which is required to run updates proxy), package manager
can use it directly. Even if this network access is through some
VPN/Tor. If a single VM would be configured as both proxy provider and
proxy user, connection would loop back to itself. Because of this, proxy
connection redirection (to qrexec service) is disabled when the same VM
also run updates proxy.
FixesQubesOS/qubes-issues#1854
Up until today, Qubes OS would insist on either masking or disabling
or activating units that should get their state properly changed
but only on first package install (when the template is built).
This commit adds the possibility of having two types of unit presets:
* Initial presets: these are only changed state during first package
installs.
* Upgrade presets: these get their state changed during first
package installs as well as during upgrades.
All the maintainer has to do is abide by the instructions in the
preset file. Nothing else is necessary.
Namely, this allows users to enable SSHD on their templates or
standalone VMs and still keep it enabled even after the
qubes-core-vm-systemd package is upgraded.
Matt really wanted that, and so did I, so now we can do it!
:-)
There were multiple problems with reusing existing one:
- need to sync with upstream changes (configuration path etc)
- conflicts resolution on updates
- lack of iptables --wait, which causes firewall fail to load sometimes
QubesOS/qubes-issues#1067
