IOS-742 implement wgOpenInTunnelICMP

[acb-mv]

An implementation of wgOpenInTunnelICMP, which returns a pair of file descriptors for an ICMP connection

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This change is 

[pinkisemils]

I think we might have to do all the parsing of ICMP packets in the go side and use single byte writes to issue ICMP request packets, for fear of non-atomic writes over the pipe. However, if we can make do without that, that'd be ideal. So far, this looks good, and I'm anxiously waiting on the unit tests.

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @acb-mv)

[pinkisemils]

Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @acb-mv)

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Sources/WireGuardKitGo/api-apple.go line 299 at r1 (raw file):

	rxShutdown := make(chan struct{})
	go func() { // the sender
		select {

This function would benefit from a

defer send_r.Close()

Same for the other go routine.

[houmie]

Hello @pinkisemils,

Apologies, the issue section is not open, so I had no choice but to address this here.

The commit cdd6038 breaks the connection handshake, and I can no longer connect to the Wireguard servers.

However, when I revert to the previous commit, 15242e1, everything works again.

Has the former commit been tested, or is it still experimental?

Many thanks.

[pinkisemils]

Hiya @houmie, are you using our repo to build the vanilla WireGuard app? If so, I'd suggest you do not - the changes we make in this repository are there to only serve Mullvad's iOS app and we're only looking to make changes to WireGuardKit. We don't intend to have this repo work for any other usecase. In any case, this PR is not the best place to ask for support either.

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @acb-mv)