Hi all!
A bit of background: we are running an IPFS node on Android and after upgrading to the latest SDK started seeing errors like avc: denied { bind } for scontext=u:r:untrusted_app:s0:c154,c256,c512,c768 tcontext=u:r:untrusted_app:s0:c154,c256,c512,c768 tclass=netlink_route_socket permissive=0 b/155595000 app=... and {"level":"error","ts":"2021-12-15T13:26:14.324Z","logger":"basichost","caller":"basic/basic_host.go:300","msg":"failed to resolve local interface addresses","error":"route ip+net: netlinkrib: permission denied"}
So after a bit of digging we found out that this happens due to BasicHost method updateLocalIpAddr() calling manet.InterfaceMultiaddrs() (which calls net.InterfaceAddrs() which calls syscall.NetlinkRIB(syscall.RTM_GETLINK, syscall.AF_UNSPEC)).
Also another error comes from netroute.New(), but this is not so important if we find a solution for net.InterfaceAddrs()). Ultimately breaking changes were described here: Best practices for unique identifiers  | Android Developers
To fix this we tried 2 approaches:
- replicate the luni/src/main/java/java/net/NetworkInterface.java - platform/libcore - Git at Google in Go, but this approach failed because we can’t access
sys/class/neton a non rooted device - create a go-mobile binding to a java object (in our case an interface called
InterfaceAddrGetter) and pass it togo-multiaddrwhich worked for us, but this is far from pretty, because now we have to maintain our fork ofgo-multiaddrand also implement some part of logic on Android side.
The question is how you guys are planning to handle this and if the option that we chose is the most feasible way to handle such problem. If yes we can try to provide some mechanism to inject this kind of object inside libp2p to solve this problem and provide a PR.
Thanks!