mirror of
https://github.com/fosrl/olm.git
synced 2026-02-23 21:36:40 +00:00
Network manager working by adding a config file
This commit is contained in:
Owen
294
dns/platform/network_manager.go
Normal file
294
dns/platform/network_manager.go
Normal file
@@ -0,0 +1,294 @@
|
||||
//go:build (linux && !android) || freebsd
|
||||
|
||||
package dns
|
||||
|
||||
import (
|
||||
"context"
|
||||
"errors"
|
||||
"fmt"
|
||||
"net/netip"
|
||||
"os"
|
||||
"strings"
|
||||
"time"
|
||||
|
||||
dbus "github.com/godbus/dbus/v5"
|
||||
)
|
||||
|
||||
const (
|
||||
// NetworkManager D-Bus constants
|
||||
networkManagerDest = "org.freedesktop.NetworkManager"
|
||||
networkManagerDbusObjectNode = "/org/freedesktop/NetworkManager"
|
||||
networkManagerDbusDNSManagerInterface = "org.freedesktop.NetworkManager.DnsManager"
|
||||
networkManagerDbusDNSManagerObjectNode = networkManagerDbusObjectNode + "/DnsManager"
|
||||
networkManagerDbusDNSManagerModeProperty = networkManagerDbusDNSManagerInterface + ".Mode"
|
||||
networkManagerDbusVersionProperty = "org.freedesktop.NetworkManager.Version"
|
||||
|
||||
// NetworkManager dispatcher script path
|
||||
networkManagerDispatcherDir = "/etc/NetworkManager/dispatcher.d"
|
||||
networkManagerConfDir = "/etc/NetworkManager/conf.d"
|
||||
networkManagerDNSConfFile = "olm-dns.conf"
|
||||
networkManagerDispatcherFile = "01-olm-dns"
|
||||
)
|
||||
|
||||
// NetworkManagerDNSConfigurator manages DNS settings using NetworkManager configuration files
|
||||
// This approach works with unmanaged interfaces by modifying NetworkManager's global DNS settings
|
||||
type NetworkManagerDNSConfigurator struct {
|
||||
ifaceName string
|
||||
originalState *DNSState
|
||||
confPath string
|
||||
dispatchPath string
|
||||
}
|
||||
|
||||
// NewNetworkManagerDNSConfigurator creates a new NetworkManager DNS configurator
|
||||
func NewNetworkManagerDNSConfigurator(ifaceName string) (*NetworkManagerDNSConfigurator, error) {
|
||||
if ifaceName == "" {
|
||||
return nil, fmt.Errorf("interface name is required")
|
||||
}
|
||||
|
||||
// Check that NetworkManager conf.d directory exists
|
||||
if _, err := os.Stat(networkManagerConfDir); os.IsNotExist(err) {
|
||||
return nil, fmt.Errorf("NetworkManager conf.d directory not found: %s", networkManagerConfDir)
|
||||
}
|
||||
|
||||
return &NetworkManagerDNSConfigurator{
|
||||
ifaceName: ifaceName,
|
||||
confPath: networkManagerConfDir + "/" + networkManagerDNSConfFile,
|
||||
dispatchPath: networkManagerDispatcherDir + "/" + networkManagerDispatcherFile,
|
||||
}, nil
|
||||
}
|
||||
|
||||
// Name returns the configurator name
|
||||
func (n *NetworkManagerDNSConfigurator) Name() string {
|
||||
return "network-manager"
|
||||
}
|
||||
|
||||
// SetDNS sets the DNS servers and returns the original servers
|
||||
func (n *NetworkManagerDNSConfigurator) SetDNS(servers []netip.Addr) ([]netip.Addr, error) {
|
||||
// Get current DNS settings before overriding
|
||||
originalServers, err := n.GetCurrentDNS()
|
||||
if err != nil {
|
||||
// If we can't get current DNS, proceed anyway
|
||||
originalServers = []netip.Addr{}
|
||||
}
|
||||
|
||||
// Store original state
|
||||
n.originalState = &DNSState{
|
||||
OriginalServers: originalServers,
|
||||
ConfiguratorName: n.Name(),
|
||||
}
|
||||
|
||||
// Apply new DNS servers
|
||||
if err := n.applyDNSServers(servers); err != nil {
|
||||
return nil, fmt.Errorf("apply DNS servers: %w", err)
|
||||
}
|
||||
|
||||
return originalServers, nil
|
||||
}
|
||||
|
||||
// RestoreDNS restores the original DNS configuration
|
||||
func (n *NetworkManagerDNSConfigurator) RestoreDNS() error {
|
||||
// Remove our configuration file
|
||||
if err := os.Remove(n.confPath); err != nil && !os.IsNotExist(err) {
|
||||
return fmt.Errorf("remove DNS config file: %w", err)
|
||||
}
|
||||
|
||||
// Reload NetworkManager to apply the change
|
||||
if err := n.reloadNetworkManager(); err != nil {
|
||||
return fmt.Errorf("reload NetworkManager: %w", err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// GetCurrentDNS returns the currently configured DNS servers by reading /etc/resolv.conf
|
||||
func (n *NetworkManagerDNSConfigurator) GetCurrentDNS() ([]netip.Addr, error) {
|
||||
content, err := os.ReadFile("/etc/resolv.conf")
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("read resolv.conf: %w", err)
|
||||
}
|
||||
|
||||
var servers []netip.Addr
|
||||
lines := strings.Split(string(content), "\n")
|
||||
for _, line := range lines {
|
||||
line = strings.TrimSpace(line)
|
||||
if strings.HasPrefix(line, "nameserver") {
|
||||
fields := strings.Fields(line)
|
||||
if len(fields) >= 2 {
|
||||
if addr, err := netip.ParseAddr(fields[1]); err == nil {
|
||||
servers = append(servers, addr)
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
return servers, nil
|
||||
}
|
||||
|
||||
// applyDNSServers applies DNS server configuration via NetworkManager config file
|
||||
func (n *NetworkManagerDNSConfigurator) applyDNSServers(servers []netip.Addr) error {
|
||||
if len(servers) == 0 {
|
||||
return fmt.Errorf("no DNS servers provided")
|
||||
}
|
||||
|
||||
// Build DNS server list
|
||||
var dnsServers []string
|
||||
for _, server := range servers {
|
||||
dnsServers = append(dnsServers, server.String())
|
||||
}
|
||||
|
||||
// Create NetworkManager configuration file that sets global DNS
|
||||
// This overrides DNS for all connections
|
||||
configContent := fmt.Sprintf(`# Generated by Olm DNS Manager - DO NOT EDIT
|
||||
# This file configures NetworkManager to use Olm's DNS proxy
|
||||
|
||||
[global-dns-domain-*]
|
||||
servers=%s
|
||||
`, strings.Join(dnsServers, ","))
|
||||
|
||||
// Write the configuration file
|
||||
if err := os.WriteFile(n.confPath, []byte(configContent), 0644); err != nil {
|
||||
return fmt.Errorf("write DNS config file: %w", err)
|
||||
}
|
||||
|
||||
// Reload NetworkManager to apply the new configuration
|
||||
if err := n.reloadNetworkManager(); err != nil {
|
||||
// Try to clean up
|
||||
os.Remove(n.confPath)
|
||||
return fmt.Errorf("reload NetworkManager: %w", err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// reloadNetworkManager tells NetworkManager to reload its configuration
|
||||
func (n *NetworkManagerDNSConfigurator) reloadNetworkManager() error {
|
||||
conn, err := dbus.SystemBus()
|
||||
if err != nil {
|
||||
return fmt.Errorf("connect to system bus: %w", err)
|
||||
}
|
||||
defer conn.Close()
|
||||
|
||||
obj := conn.Object(networkManagerDest, networkManagerDbusObjectNode)
|
||||
|
||||
ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
|
||||
defer cancel()
|
||||
|
||||
// Call Reload method with flags=0 (reload everything)
|
||||
// See: https://networkmanager.dev/docs/api/latest/gdbus-org.freedesktop.NetworkManager.html#gdbus-method-org-freedesktop-NetworkManager.Reload
|
||||
err = obj.CallWithContext(ctx, networkManagerDest+".Reload", 0, uint32(0)).Store()
|
||||
if err != nil {
|
||||
return fmt.Errorf("call Reload: %w", err)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// IsNetworkManagerAvailable checks if NetworkManager is available and responsive
|
||||
func IsNetworkManagerAvailable() bool {
|
||||
conn, err := dbus.SystemBus()
|
||||
if err != nil {
|
||||
return false
|
||||
}
|
||||
defer conn.Close()
|
||||
|
||||
obj := conn.Object(networkManagerDest, networkManagerDbusObjectNode)
|
||||
|
||||
ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
|
||||
defer cancel()
|
||||
|
||||
// Try to ping NetworkManager
|
||||
if err := obj.CallWithContext(ctx, "org.freedesktop.DBus.Peer.Ping", 0).Store(); err != nil {
|
||||
return false
|
||||
}
|
||||
|
||||
return true
|
||||
}
|
||||
|
||||
// IsNetworkManagerDNSModeSupported checks if NetworkManager's DNS mode is one we can work with
|
||||
// Some DNS modes delegate to other systems (like systemd-resolved) which we should use directly
|
||||
func IsNetworkManagerDNSModeSupported() bool {
|
||||
conn, err := dbus.SystemBus()
|
||||
if err != nil {
|
||||
return false
|
||||
}
|
||||
defer conn.Close()
|
||||
|
||||
obj := conn.Object(networkManagerDest, networkManagerDbusDNSManagerObjectNode)
|
||||
|
||||
modeVariant, err := obj.GetProperty(networkManagerDbusDNSManagerModeProperty)
|
||||
if err != nil {
|
||||
// If we can't get the mode, assume it's not supported
|
||||
return false
|
||||
}
|
||||
|
||||
mode, ok := modeVariant.Value().(string)
|
||||
if !ok {
|
||||
return false
|
||||
}
|
||||
|
||||
// If NetworkManager is delegating DNS to systemd-resolved, we should use
|
||||
// systemd-resolved directly for better control
|
||||
switch mode {
|
||||
case "systemd-resolved":
|
||||
// NetworkManager is delegating to systemd-resolved
|
||||
// We should use systemd-resolved configurator instead
|
||||
return false
|
||||
case "dnsmasq", "unbound":
|
||||
// NetworkManager is using a local resolver that it controls
|
||||
// We can configure DNS through NetworkManager
|
||||
return true
|
||||
case "default", "none", "":
|
||||
// NetworkManager is managing DNS directly or not at all
|
||||
// We can configure DNS through NetworkManager
|
||||
return true
|
||||
default:
|
||||
// Unknown mode, try to use it
|
||||
return true
|
||||
}
|
||||
}
|
||||
|
||||
// GetNetworkManagerDNSMode returns the current DNS mode of NetworkManager
|
||||
func GetNetworkManagerDNSMode() (string, error) {
|
||||
conn, err := dbus.SystemBus()
|
||||
if err != nil {
|
||||
return "", fmt.Errorf("connect to system bus: %w", err)
|
||||
}
|
||||
defer conn.Close()
|
||||
|
||||
obj := conn.Object(networkManagerDest, networkManagerDbusDNSManagerObjectNode)
|
||||
|
||||
modeVariant, err := obj.GetProperty(networkManagerDbusDNSManagerModeProperty)
|
||||
if err != nil {
|
||||
return "", fmt.Errorf("get DNS mode property: %w", err)
|
||||
}
|
||||
|
||||
mode, ok := modeVariant.Value().(string)
|
||||
if !ok {
|
||||
return "", errors.New("DNS mode is not a string")
|
||||
}
|
||||
|
||||
return mode, nil
|
||||
}
|
||||
|
||||
// GetNetworkManagerVersion returns the version of NetworkManager
|
||||
func GetNetworkManagerVersion() (string, error) {
|
||||
conn, err := dbus.SystemBus()
|
||||
if err != nil {
|
||||
return "", fmt.Errorf("connect to system bus: %w", err)
|
||||
}
|
||||
defer conn.Close()
|
||||
|
||||
obj := conn.Object(networkManagerDest, networkManagerDbusObjectNode)
|
||||
|
||||
versionVariant, err := obj.GetProperty(networkManagerDbusVersionProperty)
|
||||
if err != nil {
|
||||
return "", fmt.Errorf("get version property: %w", err)
|
||||
}
|
||||
|
||||
version, ok := versionVariant.Value().(string)
|
||||
if !ok {
|
||||
return "", errors.New("version is not a string")
|
||||
}
|
||||
|
||||
return version, nil
|
||||
}
|
||||
Reference in New Issue
Block a user