netbird/client/internal/routemanager/systemops_nonandroid_test.go
Viktor Liu 2475473227
Support client default routes for Linux (#1667)
All routes are now installed in a custom netbird routing table.
Management and wireguard traffic is now marked with a custom fwmark.
When the mark is present the traffic is routed via the main routing table, bypassing the VPN.
When the mark is absent the traffic is routed via the netbird routing table, if:
- there's no match in the main routing table
- it would match the default route in the routing table

IPv6 traffic is blocked when a default route IPv4 route is configured to avoid leakage.
2024-03-21 16:49:28 +01:00

283 lines
9.2 KiB
Go

//go:build !android
package routemanager
import (
"bytes"
"fmt"
"net"
"net/netip"
"os"
"os/exec"
"runtime"
"strings"
"testing"
"github.com/pion/transport/v3/stdnet"
log "github.com/sirupsen/logrus"
"github.com/stretchr/testify/assert"
"github.com/stretchr/testify/require"
"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
"github.com/netbirdio/netbird/iface"
)
func assertWGOutInterface(t *testing.T, prefix netip.Prefix, wgIface *iface.WGIface, invert bool) {
t.Helper()
if runtime.GOOS == "linux" {
outIntf, err := getOutgoingInterfaceLinux(prefix.Addr().String())
require.NoError(t, err, "getOutgoingInterfaceLinux should not return error")
if invert {
require.NotEqual(t, wgIface.Name(), outIntf, "outgoing interface should not be the wireguard interface")
} else {
require.Equal(t, wgIface.Name(), outIntf, "outgoing interface should be the wireguard interface")
}
return
}
prefixGateway, err := getExistingRIBRouteGateway(prefix)
require.NoError(t, err, "getExistingRIBRouteGateway should not return err")
if invert {
assert.NotEqual(t, wgIface.Address().IP.String(), prefixGateway.String(), "route should not point to wireguard interface IP")
} else {
assert.Equal(t, wgIface.Address().IP.String(), prefixGateway.String(), "route should point to wireguard interface IP")
}
}
func getOutgoingInterfaceLinux(destination string) (string, error) {
cmd := exec.Command("ip", "route", "get", destination)
output, err := cmd.Output()
if err != nil {
return "", fmt.Errorf("executing ip route get: %w", err)
}
return parseOutgoingInterface(string(output)), nil
}
func parseOutgoingInterface(routeGetOutput string) string {
fields := strings.Fields(routeGetOutput)
for i, field := range fields {
if field == "dev" && i+1 < len(fields) {
return fields[i+1]
}
}
return ""
}
func TestAddRemoveRoutes(t *testing.T) {
testCases := []struct {
name string
prefix netip.Prefix
shouldRouteToWireguard bool
shouldBeRemoved bool
}{
{
name: "Should Add And Remove Route 100.66.120.0/24",
prefix: netip.MustParsePrefix("100.66.120.0/24"),
shouldRouteToWireguard: true,
shouldBeRemoved: true,
},
{
name: "Should Not Add Or Remove Route 127.0.0.1/32",
prefix: netip.MustParsePrefix("127.0.0.1/32"),
shouldRouteToWireguard: false,
shouldBeRemoved: false,
},
}
for n, testCase := range testCases {
t.Run(testCase.name, func(t *testing.T) {
peerPrivateKey, _ := wgtypes.GeneratePrivateKey()
newNet, err := stdnet.NewNet()
if err != nil {
t.Fatal(err)
}
wgInterface, err := iface.NewWGIFace(fmt.Sprintf("utun53%d", n), "100.65.75.2/24", 33100, peerPrivateKey.String(), iface.DefaultMTU, newNet, nil)
require.NoError(t, err, "should create testing WGIface interface")
defer wgInterface.Close()
err = wgInterface.Create()
require.NoError(t, err, "should create testing wireguard interface")
require.NoError(t, setupRouting())
t.Cleanup(func() {
assert.NoError(t, cleanupRouting())
})
err = addToRouteTableIfNoExists(testCase.prefix, wgInterface.Address().IP.String(), wgInterface.Name())
require.NoError(t, err, "addToRouteTableIfNoExists should not return err")
if testCase.shouldRouteToWireguard {
assertWGOutInterface(t, testCase.prefix, wgInterface, false)
} else {
assertWGOutInterface(t, testCase.prefix, wgInterface, true)
}
exists, err := existsInRouteTable(testCase.prefix)
require.NoError(t, err, "existsInRouteTable should not return err")
if exists && testCase.shouldRouteToWireguard {
err = removeFromRouteTableIfNonSystem(testCase.prefix, wgInterface.Address().IP.String(), wgInterface.Name())
require.NoError(t, err, "removeFromRouteTableIfNonSystem should not return err")
prefixGateway, err := getExistingRIBRouteGateway(testCase.prefix)
require.NoError(t, err, "getExistingRIBRouteGateway should not return err")
internetGateway, err := getExistingRIBRouteGateway(netip.MustParsePrefix("0.0.0.0/0"))
require.NoError(t, err)
if testCase.shouldBeRemoved {
require.Equal(t, internetGateway, prefixGateway, "route should be pointing to default internet gateway")
} else {
require.NotEqual(t, internetGateway, prefixGateway, "route should be pointing to a different gateway than the internet gateway")
}
}
})
}
}
func TestGetExistingRIBRouteGateway(t *testing.T) {
gateway, err := getExistingRIBRouteGateway(netip.MustParsePrefix("0.0.0.0/0"))
if err != nil {
t.Fatal("shouldn't return error when fetching the gateway: ", err)
}
if gateway == nil {
t.Fatal("should return a gateway")
}
addresses, err := net.InterfaceAddrs()
if err != nil {
t.Fatal("shouldn't return error when fetching interface addresses: ", err)
}
var testingIP string
var testingPrefix netip.Prefix
for _, address := range addresses {
if address.Network() != "ip+net" {
continue
}
prefix := netip.MustParsePrefix(address.String())
if !prefix.Addr().IsLoopback() && prefix.Addr().Is4() {
testingIP = prefix.Addr().String()
testingPrefix = prefix.Masked()
break
}
}
localIP, err := getExistingRIBRouteGateway(testingPrefix)
if err != nil {
t.Fatal("shouldn't return error: ", err)
}
if localIP == nil {
t.Fatal("should return a gateway for local network")
}
if localIP.String() == gateway.String() {
t.Fatal("local ip should not match with gateway IP")
}
if localIP.String() != testingIP {
t.Fatalf("local ip should match with testing IP: want %s got %s", testingIP, localIP.String())
}
}
func TestAddExistAndRemoveRouteNonAndroid(t *testing.T) {
defaultGateway, err := getExistingRIBRouteGateway(netip.MustParsePrefix("0.0.0.0/0"))
t.Log("defaultGateway: ", defaultGateway)
if err != nil {
t.Fatal("shouldn't return error when fetching the gateway: ", err)
}
testCases := []struct {
name string
prefix netip.Prefix
preExistingPrefix netip.Prefix
shouldAddRoute bool
}{
{
name: "Should Add And Remove random Route",
prefix: netip.MustParsePrefix("99.99.99.99/32"),
shouldAddRoute: true,
},
{
name: "Should Not Add Route if overlaps with default gateway",
prefix: netip.MustParsePrefix(defaultGateway.String() + "/31"),
shouldAddRoute: false,
},
{
name: "Should Add Route if bigger network exists",
prefix: netip.MustParsePrefix("100.100.100.0/24"),
preExistingPrefix: netip.MustParsePrefix("100.100.0.0/16"),
shouldAddRoute: true,
},
{
name: "Should Add Route if smaller network exists",
prefix: netip.MustParsePrefix("100.100.0.0/16"),
preExistingPrefix: netip.MustParsePrefix("100.100.100.0/24"),
shouldAddRoute: true,
},
{
name: "Should Not Add Route if same network exists",
prefix: netip.MustParsePrefix("100.100.0.0/16"),
preExistingPrefix: netip.MustParsePrefix("100.100.0.0/16"),
shouldAddRoute: false,
},
}
for n, testCase := range testCases {
var buf bytes.Buffer
log.SetOutput(&buf)
defer func() {
log.SetOutput(os.Stderr)
}()
t.Run(testCase.name, func(t *testing.T) {
peerPrivateKey, _ := wgtypes.GeneratePrivateKey()
newNet, err := stdnet.NewNet()
if err != nil {
t.Fatal(err)
}
wgInterface, err := iface.NewWGIFace(fmt.Sprintf("utun53%d", n), "100.65.75.2/24", 33100, peerPrivateKey.String(), iface.DefaultMTU, newNet, nil)
require.NoError(t, err, "should create testing WGIface interface")
defer wgInterface.Close()
err = wgInterface.Create()
require.NoError(t, err, "should create testing wireguard interface")
require.NoError(t, setupRouting())
t.Cleanup(func() {
assert.NoError(t, cleanupRouting())
})
MockAddr := wgInterface.Address().IP.String()
// Prepare the environment
if testCase.preExistingPrefix.IsValid() {
err := addToRouteTableIfNoExists(testCase.preExistingPrefix, MockAddr, wgInterface.Name())
require.NoError(t, err, "should not return err when adding pre-existing route")
}
// Add the route
err = addToRouteTableIfNoExists(testCase.prefix, MockAddr, wgInterface.Name())
require.NoError(t, err, "should not return err when adding route")
if testCase.shouldAddRoute {
// test if route exists after adding
ok, err := existsInRouteTable(testCase.prefix)
require.NoError(t, err, "should not return err")
require.True(t, ok, "route should exist")
// remove route again if added
err = removeFromRouteTableIfNonSystem(testCase.prefix, MockAddr, wgInterface.Name())
require.NoError(t, err, "should not return err")
}
// route should either not have been added or should have been removed
// In case of already existing route, it should not have been added (but still exist)
ok, err := existsInRouteTable(testCase.prefix)
t.Log("Buffer string: ", buf.String())
require.NoError(t, err, "should not return err")
// Linux uses a separate routing table, so the route can exist in both tables.
// The main routing table takes precedence over the wireguard routing table.
if !strings.Contains(buf.String(), "because it already exists") && runtime.GOOS != "linux" {
require.False(t, ok, "route should not exist")
}
})
}
}