Klemens Nanni 98a6fdb4f2
tun: bsd: remove redundant ioctl to set MTU (#1172)
wireguard's CreateTUN() sets the MTU using the same ioctl(2), on both
FreeBSD and OpenBSD.

Tested on OpenBSD (outputwith this patch):

```
# ktrace ./yggdrasil -autoconf | grep Interface
2024/09/24 17:26:29 Interface name: tun0
2024/09/24 17:26:29 Interface IPv6: 201:26e:68f0:502e:f445:13eb:2fe1:f7cd/7
2024/09/24 17:26:29 Interface MTU: 16384
```

```
$ ifconfig tun0 | head -n1
tun0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 16384
```

```
# kdump | grep ioctl
 53097 yggdrasil CALL  ioctl(10,SIOCGIFMTU,0xc0000376b8)
 53097 yggdrasil RET   ioctl 0
 53097 yggdrasil CALL  ioctl(10,SIOCSIFMTU,0xc0000376c0)
 53097 yggdrasil RET   ioctl 0
 53097 yggdrasil CALL  ioctl(10,SIOCGIFMTU,0xc0000377f8)
 53097 yggdrasil RET   ioctl 0
 53097 yggdrasil CALL  ioctl(10,_IOW('i',12,0x20),0xc00003777c)
 53097 yggdrasil RET   ioctl -1 errno 25 Inappropriate ioctl for device
       "2024/09/24 17:26:29 Error in SIOCSIFADDR_IN6: inappropriate ioctl for device
```

(The completely broken address ioctl is another story...)
2024-09-29 21:05:38 +01:00
..
2024-05-27 21:57:28 +01:00