Move network/environment to netenv

netenv/network-change.go

@@ -0,0 +1,91 @@
+package netenv
+
+import (
+	"bytes"
+	"context"
+	"crypto/sha1" //nolint:gosec // not used for security
+	"io"
+	"net"
+	"time"
+
+	"github.com/safing/portbase/log"
+)
+
+var (
+	networkChangeCheckTrigger = make(chan struct{}, 1)
+)
+
+func triggerNetworkChangeCheck() {
+	select {
+	case networkChangeCheckTrigger <- struct{}{}:
+	default:
+	}
+}
+
+func monitorNetworkChanges(ctx context.Context) error {
+	var lastNetworkChecksum []byte
+
+serviceLoop:
+	for {
+		trigger := false
+
+		// wait for trigger
+		if GetOnlineStatus() == StatusOnline {
+			select {
+			case <-ctx.Done():
+				return nil
+			case <-networkChangeCheckTrigger:
+			case <-time.After(1 * time.Minute):
+				trigger = true
+			}
+		} else {
+			select {
+			case <-ctx.Done():
+				return nil
+			case <-networkChangeCheckTrigger:
+			case <-time.After(1 * time.Second):
+				trigger = true
+			}
+		}
+
+		// check network for changes
+		// create hashsum of current network config
+		hasher := sha1.New() //nolint:gosec // not used for security
+		interfaces, err := net.Interfaces()
+		if err != nil {
+			log.Warningf("environment: failed to get interfaces: %s", err)
+			continue
+		}
+		for _, iface := range interfaces {
+			_, _ = io.WriteString(hasher, iface.Name)
+			// log.Tracef("adding: %s", iface.Name)
+			_, _ = io.WriteString(hasher, iface.Flags.String())
+			// log.Tracef("adding: %s", iface.Flags.String())
+			addrs, err := iface.Addrs()
+			if err != nil {
+				log.Warningf("environment: failed to get addrs from interface %s: %s", iface.Name, err)
+				continue
+			}
+			for _, addr := range addrs {
+				_, _ = io.WriteString(hasher, addr.String())
+				// log.Tracef("adding: %s", addr.String())
+			}
+		}
+		newChecksum := hasher.Sum(nil)
+
+		// compare checksum with last
+		if !bytes.Equal(lastNetworkChecksum, newChecksum) {
+			if len(lastNetworkChecksum) == 0 {
+				lastNetworkChecksum = newChecksum
+				continue serviceLoop
+			}
+			lastNetworkChecksum = newChecksum
+
+			if trigger {
+				triggerOnlineStatusInvestigation()
+			}
+			module.TriggerEvent(networkChangedEvent, nil)
+		}
+
+	}
+}