netbird/client/internal/dns/network_manager_linux.go
Zoltan Papp b64f5ffcb4
Mobile prerefactor (#680)
Small code cleaning in the iface package. These changes necessary to 
get a clean code in case if we involve more platforms. The OS related 
functions has been distributed into separate files and it has been 
mixed with not OS related logic. The goal is to get a clear picture 
of the layer between WireGuard and business logic.
2023-02-13 18:34:56 +01:00

303 lines
11 KiB
Go

package dns
import (
"context"
"encoding/binary"
"fmt"
"net/netip"
"regexp"
"time"
"github.com/godbus/dbus/v5"
"github.com/hashicorp/go-version"
"github.com/miekg/dns"
"github.com/netbirdio/netbird/iface"
log "github.com/sirupsen/logrus"
)
const (
networkManagerDest = "org.freedesktop.NetworkManager"
networkManagerDbusObjectNode = "/org/freedesktop/NetworkManager"
networkManagerDbusDNSManagerInterface = "org.freedesktop.NetworkManager.DnsManager"
networkManagerDbusDNSManagerObjectNode = networkManagerDbusObjectNode + "/DnsManager"
networkManagerDbusDNSManagerModeProperty = networkManagerDbusDNSManagerInterface + ".Mode"
networkManagerDbusDNSManagerRcManagerProperty = networkManagerDbusDNSManagerInterface + ".RcManager"
networkManagerDbusVersionProperty = "org.freedesktop.NetworkManager.Version"
networkManagerDbusGetDeviceByIPIfaceMethod = networkManagerDest + ".GetDeviceByIpIface"
networkManagerDbusDeviceInterface = "org.freedesktop.NetworkManager.Device"
networkManagerDbusDeviceGetAppliedConnectionMethod = networkManagerDbusDeviceInterface + ".GetAppliedConnection"
networkManagerDbusDeviceReapplyMethod = networkManagerDbusDeviceInterface + ".Reapply"
networkManagerDbusDeviceDeleteMethod = networkManagerDbusDeviceInterface + ".Delete"
networkManagerDbusDefaultBehaviorFlag networkManagerConfigBehavior = 0
networkManagerDbusIPv4Key = "ipv4"
networkManagerDbusIPv6Key = "ipv6"
networkManagerDbusDNSKey = "dns"
networkManagerDbusDNSSearchKey = "dns-search"
networkManagerDbusDNSPriorityKey = "dns-priority"
// dns priority doc https://wiki.gnome.org/Projects/NetworkManager/DNS
networkManagerDbusPrimaryDNSPriority int32 = -500
networkManagerDbusWithMatchDomainPriority int32 = 0
networkManagerDbusSearchDomainOnlyPriority int32 = 50
supportedNetworkManagerVersionConstraint = ">= 1.16, < 1.28"
)
type networkManagerDbusConfigurator struct {
dbusLinkObject dbus.ObjectPath
routingAll bool
}
// the types below are based on dbus specification, each field is mapped to a dbus type
// see https://dbus.freedesktop.org/doc/dbus-specification.html#basic-types for more details on dbus types
// see https://networkmanager.dev/docs/api/latest/gdbus-org.freedesktop.NetworkManager.Device.html on Network Manager input types
// networkManagerConnSettings maps to a (a{sa{sv}}) dbus output from GetAppliedConnection and input for Reapply methods
type networkManagerConnSettings map[string]map[string]dbus.Variant
// networkManagerConfigVersion maps to a (t) dbus output from GetAppliedConnection and input for Reapply methods
type networkManagerConfigVersion uint64
// networkManagerConfigBehavior maps to a (u) dbus input for GetAppliedConnection and Reapply methods
type networkManagerConfigBehavior uint32
// cleanDeprecatedSettings cleans deprecated settings that still returned by
// the GetAppliedConnection methods but can't be reApplied
func (s networkManagerConnSettings) cleanDeprecatedSettings() {
for _, key := range []string{"addresses", "routes"} {
delete(s[networkManagerDbusIPv4Key], key)
delete(s[networkManagerDbusIPv6Key], key)
}
}
func newNetworkManagerDbusConfigurator(wgInterface *iface.WGIface) (hostManager, error) {
obj, closeConn, err := getDbusObject(networkManagerDest, networkManagerDbusObjectNode)
if err != nil {
return nil, err
}
defer closeConn()
var s string
err = obj.Call(networkManagerDbusGetDeviceByIPIfaceMethod, dbusDefaultFlag, wgInterface.Name()).Store(&s)
if err != nil {
return nil, err
}
log.Debugf("got network manager dbus Link Object: %s from net interface %s", s, wgInterface.Name())
return &networkManagerDbusConfigurator{
dbusLinkObject: dbus.ObjectPath(s),
}, nil
}
func (n *networkManagerDbusConfigurator) applyDNSConfig(config hostDNSConfig) error {
connSettings, configVersion, err := n.getAppliedConnectionSettings()
if err != nil {
return fmt.Errorf("got an error while retrieving the applied connection settings, error: %s", err)
}
connSettings.cleanDeprecatedSettings()
dnsIP, err := netip.ParseAddr(config.serverIP)
if err != nil {
return fmt.Errorf("unable to parse ip address, error: %s", err)
}
convDNSIP := binary.LittleEndian.Uint32(dnsIP.AsSlice())
connSettings[networkManagerDbusIPv4Key][networkManagerDbusDNSKey] = dbus.MakeVariant([]uint32{convDNSIP})
var (
searchDomains []string
matchDomains []string
)
for _, dConf := range config.domains {
if dConf.disabled {
continue
}
if dConf.matchOnly {
matchDomains = append(matchDomains, "~."+dns.Fqdn(dConf.domain))
continue
}
searchDomains = append(searchDomains, dns.Fqdn(dConf.domain))
}
newDomainList := append(searchDomains, matchDomains...)
priority := networkManagerDbusSearchDomainOnlyPriority
switch {
case config.routeAll:
priority = networkManagerDbusPrimaryDNSPriority
newDomainList = append(newDomainList, "~.")
if !n.routingAll {
log.Infof("configured %s:%d as main DNS forwarder for this peer", config.serverIP, config.serverPort)
}
case len(matchDomains) > 0:
priority = networkManagerDbusWithMatchDomainPriority
}
if priority != networkManagerDbusPrimaryDNSPriority && n.routingAll {
log.Infof("removing %s:%d as main DNS forwarder for this peer", config.serverIP, config.serverPort)
n.routingAll = false
}
connSettings[networkManagerDbusIPv4Key][networkManagerDbusDNSPriorityKey] = dbus.MakeVariant(priority)
connSettings[networkManagerDbusIPv4Key][networkManagerDbusDNSSearchKey] = dbus.MakeVariant(newDomainList)
log.Infof("adding %d search domains and %d match domains. Search list: %s , Match list: %s", len(searchDomains), len(matchDomains), searchDomains, matchDomains)
err = n.reApplyConnectionSettings(connSettings, configVersion)
if err != nil {
return fmt.Errorf("got an error while reapplying the connection with new settings, error: %s", err)
}
return nil
}
func (n *networkManagerDbusConfigurator) restoreHostDNS() error {
// once the interface is gone network manager cleans all config associated with it
return n.deleteConnectionSettings()
}
func (n *networkManagerDbusConfigurator) getAppliedConnectionSettings() (networkManagerConnSettings, networkManagerConfigVersion, error) {
obj, closeConn, err := getDbusObject(networkManagerDest, n.dbusLinkObject)
if err != nil {
return nil, 0, fmt.Errorf("got error while attempting to retrieve the applied connection settings, err: %s", err)
}
defer closeConn()
ctx, cancel := context.WithTimeout(context.TODO(), 5*time.Second)
defer cancel()
var (
connSettings networkManagerConnSettings
configVersion networkManagerConfigVersion
)
err = obj.CallWithContext(ctx, networkManagerDbusDeviceGetAppliedConnectionMethod, dbusDefaultFlag,
networkManagerDbusDefaultBehaviorFlag).Store(&connSettings, &configVersion)
if err != nil {
return nil, 0, fmt.Errorf("got error while calling GetAppliedConnection method with context, err: %s", err)
}
return connSettings, configVersion, nil
}
func (n *networkManagerDbusConfigurator) reApplyConnectionSettings(connSettings networkManagerConnSettings, configVersion networkManagerConfigVersion) error {
obj, closeConn, err := getDbusObject(networkManagerDest, n.dbusLinkObject)
if err != nil {
return fmt.Errorf("got error while attempting to retrieve the applied connection settings, err: %s", err)
}
defer closeConn()
ctx, cancel := context.WithTimeout(context.TODO(), 5*time.Second)
defer cancel()
err = obj.CallWithContext(ctx, networkManagerDbusDeviceReapplyMethod, dbusDefaultFlag,
connSettings, configVersion, networkManagerDbusDefaultBehaviorFlag).Store()
if err != nil {
return fmt.Errorf("got error while calling ReApply method with context, err: %s", err)
}
return nil
}
func (n *networkManagerDbusConfigurator) deleteConnectionSettings() error {
obj, closeConn, err := getDbusObject(networkManagerDest, n.dbusLinkObject)
if err != nil {
return fmt.Errorf("got error while attempting to retrieve the applied connection settings, err: %s", err)
}
defer closeConn()
ctx, cancel := context.WithTimeout(context.TODO(), 5*time.Second)
defer cancel()
err = obj.CallWithContext(ctx, networkManagerDbusDeviceDeleteMethod, dbusDefaultFlag).Store()
if err != nil {
return fmt.Errorf("got error while calling delete method with context, err: %s", err)
}
return nil
}
func isNetworkManagerSupported() bool {
return isNetworkManagerSupportedVersion() && isNetworkManagerSupportedMode()
}
func isNetworkManagerSupportedMode() bool {
var mode string
err := getNetworkManagerDNSProperty(networkManagerDbusDNSManagerModeProperty, &mode)
if err != nil {
log.Error(err)
return false
}
switch mode {
case "dnsmasq", "unbound", "systemd-resolved":
return true
default:
var rcManager string
err = getNetworkManagerDNSProperty(networkManagerDbusDNSManagerRcManagerProperty, &rcManager)
if err != nil {
log.Error(err)
return false
}
if rcManager == "unmanaged" {
return false
}
}
return true
}
func getNetworkManagerDNSProperty(property string, store any) error {
obj, closeConn, err := getDbusObject(networkManagerDest, networkManagerDbusDNSManagerObjectNode)
if err != nil {
return fmt.Errorf("got error while attempting to retrieve the network manager dns manager object, error: %s", err)
}
defer closeConn()
v, e := obj.GetProperty(property)
if e != nil {
return fmt.Errorf("got an error getting property %s: %v", property, e)
}
return v.Store(store)
}
func isNetworkManagerSupportedVersion() bool {
obj, closeConn, err := getDbusObject(networkManagerDest, networkManagerDbusObjectNode)
if err != nil {
log.Errorf("got error while attempting to get the network manager object, err: %s", err)
return false
}
defer closeConn()
value, err := obj.GetProperty(networkManagerDbusVersionProperty)
if err != nil {
log.Errorf("unable to retrieve network manager mode, got error: %s", err)
return false
}
versionValue, err := parseVersion(value.Value().(string))
if err != nil {
return false
}
constraints, err := version.NewConstraint(supportedNetworkManagerVersionConstraint)
if err != nil {
return false
}
return constraints.Check(versionValue)
}
func parseVersion(inputVersion string) (*version.Version, error) {
reg, err := regexp.Compile(version.SemverRegexpRaw)
if err != nil {
return nil, err
}
if inputVersion == "" || !reg.MatchString(inputVersion) {
return nil, fmt.Errorf("couldn't parse the provided version: Not SemVer")
}
verObj, err := version.NewVersion(inputVersion)
if err != nil {
return nil, err
}
return verObj, nil
}