Improve module load (netbirdio#470)

* Add additional check for needed kernel modules

* Check if wireguard and tun modules are loaded

If modules are loaded return true, otherwise attempt to load them

* fix state check

* Add module function tests

* Add test execution in container

* run client package tests on docker

* add package comment to new file

* force entrypoint

* add --privileged flag

* clean only if tables where created

* run from within the directories

.github/workflows/golang-test-linux.yml

@@ -33,3 +33,55 @@ jobs:
 
       - name: Test
         run: GOARCH=${{ matrix.arch }} go test -exec 'sudo --preserve-env=CI' -timeout 5m -p 1 ./...
+
+  test_client_on_docker:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Install Go
+        uses: actions/setup-go@v2
+        with:
+          go-version: 1.18.x
+
+
+      - name: Cache Go modules
+        uses: actions/cache@v2
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
+
+      - name: Checkout code
+        uses: actions/checkout@v2
+
+      - name: Install dependencies
+        run: sudo apt update && sudo apt install -y -q libgtk-3-dev libappindicator3-dev libayatana-appindicator3-dev libgl1-mesa-dev xorg-dev
+
+      - name: Install modules
+        run: go mod tidy
+
+      - name: Generate Iface Test bin
+        run: go test -c -o iface-testing.bin ./iface/...
+
+      - name: Generate RouteManager Test bin
+        run: go test -c -o routemanager-testing.bin ./client/internal/routemanager/...
+
+      - name: Generate Engine Test bin
+        run: go test -c -o engine-testing.bin ./client/internal/*.go
+
+      - name: Generate Peer Test bin
+        run: go test -c -o peer-testing.bin ./client/internal/peer/...
+
+      - run: chmod +x *testing.bin
+
+      - name: Run Iface tests in docker
+        run: docker run -t --cap-add=NET_ADMIN --privileged --rm -v $PWD:/ci -w /ci/iface --entrypoint /busybox/sh gcr.io/distroless/base:debug -c /ci/iface-testing.bin
+
+      - name: Run RouteManager tests in docker
+        run: docker run -t --cap-add=NET_ADMIN --privileged --rm -v $PWD:/ci -w /ci/client/internal/routemanager --entrypoint /busybox/sh gcr.io/distroless/base:debug -c /ci/routemanager-testing.bin
+
+      - name: Run Engine tests in docker
+        run: docker run -t --cap-add=NET_ADMIN --privileged --rm -v $PWD:/ci -w /ci/client/internal --entrypoint /busybox/sh gcr.io/distroless/base:debug -c /ci/engine-testing.bin
+
+      - name: Run Peer tests in docker
+        run: docker run -t --cap-add=NET_ADMIN --privileged --rm -v $PWD:/ci -w /ci/client/internal/peer  --entrypoint /busybox/sh gcr.io/distroless/base:debug -c /ci/peer-testing.bin

client/internal/connect.go

@@ -107,7 +107,7 @@ func RunClient(ctx context.Context, config *Config, statusRecorder *nbStatus.Sta
 		localPeerState := nbStatus.LocalPeerState{
 			IP:              loginResp.GetPeerConfig().GetAddress(),
 			PubKey:          myPrivateKey.PublicKey().String(),
-			KernelInterface: iface.WireguardModExists(),
+			KernelInterface: iface.WireguardModuleIsLoaded(),
 		}
 
 		statusRecorder.UpdateLocalPeerState(localPeerState)

client/internal/routemanager/nftables_linux.go

@@ -84,8 +84,10 @@ func (n *nftablesManager) CleanRoutingRules() {
 	n.mux.Lock()
 	defer n.mux.Unlock()
 	log.Debug("flushing tables")
-	n.conn.FlushTable(n.tableIPv6)
-	n.conn.FlushTable(n.tableIPv4)
+	if n.tableIPv4 != nil && n.tableIPv6 != nil {
+		n.conn.FlushTable(n.tableIPv6)
+		n.conn.FlushTable(n.tableIPv4)
+	}
 	log.Debugf("flushing tables result in: %v error", n.conn.Flush())
 }
 

iface/iface_darwin.go

@@ -34,7 +34,7 @@ func (w *WGIface) assignAddr() error {
 	return nil
 }
 
-// WireguardModExists check if we can load wireguard mod (linux only)
-func WireguardModExists() bool {
+// WireguardModuleIsLoaded check if we can load wireguard mod (linux only)
+func WireguardModuleIsLoaded() bool {
 	return false
 }

iface/iface_linux.go

@@ -1,48 +1,29 @@
 package iface
 
 import (
-	"errors"
-	"math"
-	"os"
-	"syscall"
-
+	"fmt"
 	log "github.com/sirupsen/logrus"
 	"github.com/vishvananda/netlink"
+	"os"
 )
 
 type NativeLink struct {
 	Link *netlink.Link
 }
 
-// WireguardModExists check if we can load wireguard mod (linux only)
-func WireguardModExists() bool {
-	link := newWGLink("mustnotexist")
-
-	// We willingly try to create a device with an invalid
-	// MTU here as the validation of the MTU will be performed after
-	// the validation of the link kind and hence allows us to check
-	// for the existance of the wireguard module without actually
-	// creating a link.
-	//
-	// As a side-effect, this will also let the kernel lazy-load
-	// the wireguard module.
-	link.attrs.MTU = math.MaxInt
-
-	err := netlink.LinkAdd(link)
-
-	return errors.Is(err, syscall.EINVAL)
-}
-
 // Create creates a new Wireguard interface, sets a given IP and brings it up.
 // Will reuse an existing one.
 func (w *WGIface) Create() error {
 	w.mu.Lock()
 	defer w.mu.Unlock()
 
-	if WireguardModExists() {
+	if WireguardModuleIsLoaded() {
 		log.Info("using kernel WireGuard")
 		return w.createWithKernel()
 	} else {
+		if !tunModuleIsLoaded() {
+			return fmt.Errorf("couldn't check or load tun module")
+		}
 		log.Info("using userspace WireGuard")
 		return w.createWithUserspace()
 	}

iface/iface_windows.go

@@ -58,7 +58,7 @@ func (w *WGIface) UpdateAddr(newAddr string) error {
 	return w.assignAddr(luid)
 }
 
-// WireguardModExists check if we can load wireguard mod (linux only)
-func WireguardModExists() bool {
+// WireguardModuleIsLoaded check if we can load wireguard mod (linux only)
+func WireguardModuleIsLoaded() bool {
 	return false
 }