Not sure if it's kern/ or bin/, both are involved I guess.
Renaming vmnet/tap(4) interfaces, defined in rc.conf(5) via
"cloned_interfaces" e.g, isn't prohibited by rc(8)-network.subr nor by
If such a interface is renamed, the Ethernet device shows up correctly,
with the new name and ifconfig(8) also reports the new name if it's
created and renamed in the same invocation.
Problem is, the control device isn't renamed, it will keep it's initial
creation name like tap0 and I found no userland way to determine the
corresponding Ethernet IF name.
Take... I could see some use in creating an alias for it, but I'd like to see how this usually works in other OS.
Date: Thu Oct 3 17:54:00 2019
New Revision: 353057
if_tuntap: create /dev aliases when a tuntap device gets renamed
Currently, if you do:
$ ifconfig tun0 create
$ ifconfig tun0 name wg0
$ ls -l /dev | egrep 'wg|tun'
You will see tun0, but no wg0. In fact, it's slightly more annoying to make
the association between the new name and the old name in order to open the
device (if it hadn't been opened during the rename).
Register an eventhandler for ifnet_arrival_events and catch interface
renames. We can determine if the ifnet is a tun easily enough from the
if_dname, which matches the cevsw.d_name from the associated tuntap_driver.
Some locking dance is required because renames don't require the device to
be opened, so it could go away in the middle of handling the ioctl, but as
soon as we've verified this isn't the case we can attempt to busy the tun
and either bail out if the tun device is dying, or we can proceed with the
We only create these aliases on a best-effort basis. Renaming a tun device
to "usbctl", which doesn't exist as an ifnet but does as a /dev, is clearly
not that disastrous, but we can't and won't create a /dev for that.
If this can/should goto releng/12.1, please set bug 240700 in this issues Blocks field