BREAKS CONFIG COMPATIBILITY:
This commit changes the configuration interface of the NIC router in a way that
may break systems that use the component without proper adjustment!
HOW TO ADJUST:
At each occurrence of the '<uplink ...>' tag in a NIC router configuration
replace the tag name 'uplink' with 'nic-client'. The rest of the tag stays the
same.
The term "uplink" for network interfaces in the router that have a NIC session
client as back end was introduced in a time when Uplink sessions didn't yet
exist. Now, they do and, although both an uplink and an Uplink session
normally describe a network session between router and network device driver,
they are based on two different service types (NIC and Uplink). This can easily
cause confusion when integrating the router (the <uplink> is not related to
Uplink sessions) or trying to understand its functioning (an 'Uplink' object
has nothing to do with the Uplink service).
Therefore, this commit introduces the more specific term "NIC client" for an
interface that is based on a NIC session requested by the router. This doesn't
imply any semantic changes at the NIC router. However, the commit also brings a
broader update of the router's README and removes the term "downlink" that was
used only in documentation to refer to interfaces backed by a NIC session
provided by the router. The term was only associated with this meaning because
it is the natural counterpart to an uplink. This isn't appropriate anymore as
the terms for interface types have moved to a more technical level.
The commit adjusts all scenarios in the basic Genode repositories properly.
Fixes#4238
Let the NIC router provide an Uplink service besides the Nic service that it
already provided. Requests for an Uplink session towards the NIC router are
assigned to Domains using the same <policy> configuration tags that are used in
order to assign Nic session requests. The MAC addresses of Uplink session
components are _NOT_ considered during the allocation of MAC addresses for NIC
session components at the same Domain. The task of avoiding MAC address clashes
between Uplink session components and Nic session components is therefore left
to the integrator. Apart from that, Uplink session components are treated by
the NIC router like any other interface.
Ref #3961
* The NIC router now considers, memorizes, and, if configured, reports
multiple DHCP option 6 entries from DHCP replies that it received as DHCP
client
* A DHCP server at the NIC router can now be configured statically with
multiple DNS server addresses to propagate
* The 'dns_server_from' attribute of the DHCP server of the NIC router now
supports the forwarding of multiple DNS server addresses
* The automated run/nic_router_dhcp test tests all the above mentioned new
functionality and reconfiguring it at runtime. The test was added to the
autopilot.
* All run scripts were adapted to fit the new NIC router configuration
interface
Fixes#3952
Introduce the uplink tag:
! <config>
! <uplink label="wifi" domain="uplink">
! <uplink label="wired" domain="wired_bridge">
! <uplink domain="wired_bridge">
! <config/>
For each uplink tag, the NIC router requests a NIC session with the
corresponding label or an empty label if there is no label attribute.
These NIC sessions get attached to the domain that is set in their
uplink tag as soon as the domain appears. This means their lifetime is
not bound to the domain. Uplink NIC sessions can be safely moved from
one domain to another without being closed by reconfiguring the
corresponding domain attribute.
Attention: This may render previously valid NIC router configurations
useless. A domain named "uplink" doesn't automatically request a NIC
session anymore. To fix these configurations, just add
! <uplink domain="uplink"/>
or
! <uplink label="[LABEL]" domain="uplink"/>
as direct subtag of the <config> tag.
Issue #2840
A very basic test of the re-configurability. It overwrites the configuration
once without making any changes, once with removing all domains except
uplink, and a third time recovering to the initial configuration to see if
the clients keep going as soon as their domains are back.
Fixes#2670
