tap(4): allow full-duplex and non-zero speed

[igalic]

tap(4) devices advertise themselves as just 'ethernet autoselect', without duplex or speed capabilities.
This advertisement makes them unable to be aggregated into lacp-based lagg(4):

• lacp code requires underlying interfaces to be full-duplex, else interface will not participate in lacp at all
• lacp code requires underlying interface to have non-zero speed, else this interface can not be selected as active aggregator

PR#: 217374
Reported by: Alexandre Snarskii [email protected]
Co-authored-by: Mina Galić [email protected]

[igalic]

hey @snar ; i just found your Patch in Bugzilla and thought resurrecting it here would be better.

[emaste]

If this is an updated version of the patch originally submitted in the PR then we ought to use the Co-authored-by: Name <email> trailer

https://docs.github.com/en/pull-requests/committing-changes-to-your-project/creating-and-editing-commits/creating-a-commit-with-multiple-authors

[igalic]

@emaste all I've done is moved the original author's patch into the new file.
but I'll happily add myself as Co-Author for doing the work

[gmshake]

Basically looks good to me.

[gmshake]

I'd prefer 10Gbps, although higher is also possible but this keeps align with some virtual interfaces such as epair.

[igalic]

netgtaph and ether switch use IFM_1000_T, so we should bump then as well

(and vxlan doesn't set a limit… hmmmm)

[gmshake]

A common frontend vtnet (virtio-net) advertise it as Ethernet autoselect (10Gbase-T <full-duplex>) and there is no choices for supported media, so I think it should be IFM_10G_T .

root@freebsd:~ # ifconfig -m vtnet0
vtnet0: flags=8863<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=80028<VLAN_MTU,JUMBO_MTU,LINKSTATE>
        capabilities=90028<VLAN_MTU,JUMBO_MTU,VLAN_HWFILTER,LINKSTATE>
        ether 52:54:00:12:34:56
        inet 192.168.99.31 netmask 0xffffff00 broadcast 192.168.99.255
        media: Ethernet autoselect (10Gbase-T <full-duplex>)
        status: active
        supported media:
                media autoselect
        nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>

I'll test and report later.

[gmshake]

Test looks good, except the default if_baudrate (of tap interface) is not set correspondingly.

# ifconfig
tap0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=80000<LINKSTATE>
	ether 8a:d6:1b:7f:b6:28
	groups: tap
	media: Ethernet 10Gbase-T <full-duplex>
	status: active
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
	Opened by PID 56600
tap1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=80000<LINKSTATE>
	ether 8a:d6:1b:7f:b6:28
	hwaddr 6e:b3:f0:23:3d:9c
	groups: tap
	media: Ethernet 10Gbase-T <full-duplex>
	status: active
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
	Opened by PID 56600
lagg0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
	options=80000<LINKSTATE>
	ether 8a:d6:1b:7f:b6:28
	inet 192.168.199.1 netmask 0xffffff00 broadcast 192.168.199.255
	laggproto lacp lagghash l2,l3,l4
	laggport: tap0 flags=1c<ACTIVE,COLLECTING,DISTRIBUTING>
	laggport: tap1 flags=1c<ACTIVE,COLLECTING,DISTRIBUTING>
	groups: lagg
	media: Ethernet autoselect
	status: active
	nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>

[igalic]

ng does a much better job doing all of this, but it also sets every negotiable speed.

I also don't see how to access ifmedia from the point at which baudrate is set in tuntap.

I think this might need more refactoring to do right then.

[bsdimp]

I've landed this patch, even though it's imperfect in the review. It helps many things, though a future version could help even more. I'll let that future version be submitted when it's ready.