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

network/connection_android.go

@@ -0,0 +1,65 @@
+package network
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"time"
+
+	"github.com/safing/portmaster/intel"
+	"github.com/safing/portmaster/network/netutils"
+	"github.com/safing/portmaster/network/packet"
+	"github.com/safing/portmaster/process"
+	"github.com/safing/spn/navigator"
+)
+
+// NewDefaultConnection creates a new connection with default values except local and remote IPs and protocols.
+func NewDefaultConnection(localIP net.IP, localPort uint16, remoteIP net.IP, remotePort uint16, ipVersion packet.IPVersion, protocol packet.IPProtocol) *Connection {
+	connInfo := &Connection{
+		ID:           fmt.Sprintf("%s-%s-%d-%s-%d", protocol.String(), localIP, localPort, remoteIP, remotePort),
+		Type:         IPConnection,
+		External:     false,
+		IPVersion:    ipVersion,
+		Inbound:      false,
+		IPProtocol:   protocol,
+		LocalIP:      localIP,
+		LocalIPScope: netutils.Global,
+		LocalPort:    localPort,
+		Entity: &intel.Entity{
+			Protocol: uint8(protocol),
+			IP:       remoteIP,
+			Port:     remotePort,
+		},
+		Resolver:         nil,
+		Started:          time.Now().Unix(),
+		VerdictPermanent: false,
+		Tunneled:         true,
+		Encrypted:        false,
+		Internal:         false,
+		addedToMetrics:   true, // Metrics are not needed for now. This will mark the Connection to be ignored.
+		process:          process.GetUnidentifiedProcess(context.Background()),
+	}
+
+	// TODO: Quick fix for the SPN.
+	// Use inspection framework for proper encryption detection.
+	switch connInfo.Entity.DstPort() {
+	case
+		22,  // SSH
+		443, // HTTPS
+		465, // SMTP-SSL
+		853, // DoT
+		993, // IMAP-SSL
+		995: // POP3-SSL
+		connInfo.Encrypted = true
+	}
+
+	var layeredProfile = connInfo.process.Profile()
+	connInfo.TunnelOpts = &navigator.Options{
+		HubPolicies:                   layeredProfile.StackedExitHubPolicies(),
+		CheckHubExitPolicyWith:        connInfo.Entity,
+		RequireTrustedDestinationHubs: !connInfo.Encrypted,
+		RoutingProfile:                layeredProfile.SPNRoutingAlgorithm(),
+	}
+
+	return connInfo
+}