Aloha. Opening and closing VPN tunnels results in as many utun interfaces as the amount of times the tunnel has been opened. These interfaces stay present and seem to be removed only upon system reboot.
We are using the NetworkExtension as a SystemExtension on macOS to create the virtual interfaces.
Is this the normal behaviour. Has anybody else experienced this?
utun0: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1380
inet6 fe80::8038:c353:17cd:c422%utun0 prefixlen 64 scopeid 0xf
nd6 options=201<PERFORMNUD,DAD>
utun1: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 2000
inet6 fe80::cfb6:1324:d7e9:5d5%utun1 prefixlen 64 scopeid 0x10
nd6 options=201<PERFORMNUD,DAD>
utun2: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun3: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun4: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun5: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun6: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun7: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
utun8: flags=8051<UP,POINTOPOINT,RUNNING,MULTICAST> mtu 1300
options=6463<RXCSUM,TXCSUM,TSO4,TSO6,CHANNEL_IO,PARTIAL_CSUM,ZEROINVERT_CSUM>
Doesn't this increase the attack surface? It needs to be fixed because it is wasting resources and it's sloppy.When I do something like ifconfig, I get a huge list of over 100 utun interfaces left hanging. Obviously it's using memory and I expect impacts performance, at least of ifconfig if nothing else.