Fix DNS resolver problem And access to interface list

[farhoud]

Hi guy's
I have fixed these issues on the react-native project hoodchat
If you want i can create PR

[ehsan6sha]

Can you please elaborate on the issue?

[farhoud]

There is 2 major issue with Libp2p on android:

• x/mobile: Calling net.InterfaceAddrs() fails on Android SDK 30 golang/go#40569
  get interfaces on android device's return null so libp2p can not listen on any port.
• net: support for android without cgo golang/go#8877
  befor you kicked me out I was using ip4 address to bypass the problem with bootstrap nodes

[ehsan6sha]

For this problem I am a bit unclear on what the issue is?
We have a working DNS on react-native that resolves fx.land relay server to enable the app connect to any blox backend. Can you elaborate on the problem?
Here is the current relay that RN can use without issue: /dns/relay.dev.fx.land/tcp/4001/p2p/12D3KooWDRrBaAfPwsGJivBoUw5fE7ZpDiyfUjqgiURq2DEcL835/p2p-circuit/p2p/[Blox perId]

we are not calling InterfaceAddrs anywhere
Maybe a good idea to write the steps needed to break the app, so that we can see what is the exact breaking point

[ehsan6sha]

hi @farhoud how did you resolve this?

[ehsan6sha]

@farhoud This line here causes the issue you mentioned (and another line in flush)
https://github.com/functionland/go-fula/blob/32cf82417a72ea382405d953da62f31f4e2f118d/mobile/client.go#L62

[ehsan6sha]

DESCRIPTION:
The error is populated on this line of go when we compiled it for Android and imported in JAVA:
https://github.com/functionland/go-fula/blob/32cf82417a72ea382405d953da62f31f4e2f118d/mobile/client.go#L62

route ip+net: netlinkrib: permission denied
seems that error: route ip+net: netlinkrib: permission denied
is a real thing and not gone yet. It affects anything that requires discovery in the network like mdns. probabely in the features you added it is used as well
since hte issue is not closed I suspect it is still a thing: golang/go#40569 (comment)

seems they kinda solved it in ipfs shipyad, but could not fully understand how to implement in ours as well:
https://github.com/search?q=repo%3Aipfs-shipyard%2Fgomobile-ipfs%20MDNSLockerDriver%20&type=code
seems this part on Android is doing the action and htey passed it to go:
WifiManager wifi = (WifiManager) this.reactContext.getSystemService(Context.WIFI_SERVICE);
WifiManager.MulticastLock multicastLock = wifi.createMulticastLock("multicastLock");
multicastLock.setReferenceCounted(true);
multicastLock.acquire();

also I am not sure if anywhere we need this one? golang/go#40569 (comment)

[ehsan6sha]

@hhio618

[farhoud]

First you should patch the underlining packages:
w3-voice/go-multiaddr@224cf7d

create a net driver interface the same as go network driver interface

https://github.com/w3-voice/app/blob/main/go/driver_net.go

And implement the interface in java then

https://github.com/w3-voice/app/blob/main/android/core/src/main/java/fx/android/core/NetDriver.java

And then override the java driver with go driver:
https://github.com/w3-voice/app/blob/f6a901464797c98e31b66fd75292086240d39227/android/core/src/main/java/fx/android/core/CoreService.java#L131