Android support for getting network addresses and interfaces (#1056)

* Replace unsupported network functions for android

* Refactor default/android net addresses processing

* Add default connection values, Refactor netenv

* Fix compilation error

* Combine network change default/android functions

netenv/adresses.go

@@ -12,7 +12,7 @@ import (
 
 // GetAssignedAddresses returns the assigned IPv4 and IPv6 addresses of the host.
 func GetAssignedAddresses() (ipv4 []net.IP, ipv6 []net.IP, err error) {
-	addrs, err := net.InterfaceAddrs()
+	addrs, err := osGetInterfaceAddrs()
 	if err != nil {
 		return nil, nil, err
 	}
@@ -74,7 +74,7 @@ func refreshMyNetworks() error {
 	myNetworksDontRefreshUntil = time.Now().Add(1 * time.Second)
 
 	// Refresh assigned networks.
-	interfaceNetworks, err := net.InterfaceAddrs()
+	interfaceNetworks, err := osGetInterfaceAddrs()
 	if err != nil {
 		// In some cases the system blocks on this call, which piles up to
 		// literally over thousand goroutines wanting to try this again.

netenv/network-change.go

@@ -5,7 +5,6 @@ import (
 	"context"
 	"crypto/sha1"
 	"io"
-	"net"
 	"time"
 
 	"github.com/safing/portbase/log"
@@ -61,7 +60,7 @@ serviceLoop:
 		// check network for changes
 		// create hashsum of current network config
 		hasher := sha1.New() //nolint:gosec // not used for security
-		interfaces, err := net.Interfaces()
+		interfaces, err := osGetNetworkInterfaces()
 		if err != nil {
 			log.Warningf("netenv: failed to get interfaces: %s", err)
 			continue

netenv/os_android.go

@@ -0,0 +1,23 @@
+package netenv
+
+import (
+	"github.com/safing/portmaster-android/go/app_interface"
+	"net"
+)
+
+func osGetInterfaceAddrs() ([]net.Addr, error) {
+	list, err := app_interface.GetNetworkAddresses()
+	if err != nil {
+		return nil, err
+	}
+	var netList []net.Addr
+	for _, addr := range list {
+		netList = append(netList, addr.ToIPNet())
+	}
+
+	return netList, nil
+}
+
+func osGetNetworkInterfaces() ([]app_interface.NetworkInterface, error) {
+	return app_interface.GetNetworkInterfaces()
+}

netenv/os_default.go

@@ -0,0 +1,15 @@
+//go:build !android
+
+package netenv
+
+import (
+	"net"
+)
+
+func osGetInterfaceAddrs() ([]net.Addr, error) {
+	return net.InterfaceAddrs()
+}
+
+func osGetNetworkInterfaces() ([]net.Interface, error) {
+	return net.Interfaces()
+}