Hi,
this series of patches implement some required changes to make dhcpcd work on
the Hurd.
1. Make server ops return `kern_return_t`
- This one is just to fix some warnings
2. Implement `pfinet_getroutes`
- At some point dhcpcd requests a list of routes in the system. I'm calling
the
`pfinet_getroutes` op to get them. In LwIP this was not implemented so this
patch implements it based on what the pfinet translator does.
I have a question here: pfinet sets the `dealloc_data` output parameter to
true,
so I did the same. But does that mean the caller, in this case dhcpcd, is
responsible for deallocatinng the pointer? I assumed yes and do it on the
dhcpcd
patch
3. Better null termination protection
- Just a nitpick
4. Consider gateway in ip inquire and configure
- This just adds a new macro `GWADDR` to identify addresses received by
`inquire_device` and `configure_device`. This is convenient because it's
used
from new ioctls I added.
5. Additional protection in `siocsifXaddr`
- Another minor fix I found: `siocsifXaddr` should check the given address
family
6. Implement routing ioctls
- This one is important and I'd appreciate some review on this. Dhcpcd needs
a way
to create and delete routes on the system. I had to find out a way and my
approach
was to add them through ioctls, in particular `SIOCADDRT` and `SIOCDELRT`.
This
patch implements those.
The tricky part is LwIP doesn't really support routing, the only notion of
routing
LwIP has is setting a gateway for each interface. So the way to add routes
to LwIP
is configuring IP, netmask and gateway in a way packets will be routed as
expected.
This ioctls try to translate what the user tries to do into what LwIP can
do. And
some scenarios in regular Unix routing are not implemented. In fact, this
patch
only implements two scenarios:
- When adding a new route
- Client sends an interface plus a netmask but gateway=any
Intends to add a subnet route.
e.g. `192.168.1.0/24 dev eth0`
In this scenario, the function checks the given mask and destination are
compatible with current IP and sets the new mask to the given interface.
- Client sends an interface plus a gateway but netmask=any
Intends to set a default gateway.
e.g. `0.0.0.0/0 via 192.168.1.1`
In this scenario, the function checks the given gateway will be
reachable
from the given interface and sets the gateway. It also makes the
interface
default.
- When removing a route, the same two scenarios are supported. The function
checks
the given route matches the current config and then it removes the
configuration.
This is the minimal routing required by dhcpcd. It performs the next
sequence:
1. Add the leased IP to an interface through `SIOCSIFADDR`
2. Add a subnet route
3. For one interface, add a default gateway
7. Implement `SIOCDIFADDR`
- During the shutdown sequence, dhcpcd removes all routes and IPs. The LwIP
translator didn't have the `SIOCDIFADDR` implemented so I had to add it.
The patch just sets IP to INADDR_NONE.
Thanks
