windows/tun: change wintun dependency to iwanbk/wintun

[iwanbk]

Because the original wintun crate doesn't set the MTU correctly

Fixes #474

[iwanbk]

@LeeSmet
i pointed out the dependency to my branch because i consider it as temporary, the end goal would be one of these:

1. put the code in threefoldtech/wintun master branch
2. contribute the code to the upstream

My plan is going to number two first, number one is the backup

[iwanbk]

will create github issue based on our agreement

[LeeSmet]

The current fix works for us but would break users of wintun who rely on ipv4, so a commit upstream would need some more refinement. For now, I think the best way forward is to copy the fixed function over to the windows tun module here in mcyelium. We already have some other code which basically does the same after all

[iwanbk]

The current fix works for us but would break users of wintun who rely on ipv4, so a commit upstream would need some more refinement

yes, of course.

For now, I think the best way forward is to copy the fixed function over to the windows tun module here in mcyelium

you meant copying this code (and maybe other deps or modify it)
https://github.com/iwanbk/wintun/blob/f2e5353c54cc6a8486b55112dc0de6e016491a8a/src/util.rs#L383-L413

Looks like that is also possible

We already have some other code which basically does the same after all

Can you elaborate more about this?

[LeeSmet]

We currently already rely on netsh being available for windows as it is used to set the ipv6 address: https://github.com/threefoldtech/mycelium/blob/master/mycelium/src/tun/windows.rs#L119, so just copying the function and putting it here should be fine (i.e. running the netsh command to set the ipv6 mtu)

[iwanbk]

okay, looks better

[iwanbk]

OK, i close it in favor of #487