netmaker/netclient/functions/daemon.go
2022-07-07 13:17:08 -04:00

339 lines
11 KiB
Go

package functions
import (
"context"
"crypto/ed25519"
"crypto/rand"
"crypto/tls"
"crypto/x509"
"errors"
"fmt"
"log"
"os"
"os/signal"
"strings"
"sync"
"syscall"
"time"
mqtt "github.com/eclipse/paho.mqtt.golang"
"github.com/gravitl/netmaker/logger"
"github.com/gravitl/netmaker/mq"
"github.com/gravitl/netmaker/netclient/auth"
"github.com/gravitl/netmaker/netclient/config"
"github.com/gravitl/netmaker/netclient/daemon"
"github.com/gravitl/netmaker/netclient/local"
"github.com/gravitl/netmaker/netclient/ncutils"
"github.com/gravitl/netmaker/netclient/wireguard"
ssl "github.com/gravitl/netmaker/tls"
"golang.zx2c4.com/wireguard/wgctrl/wgtypes"
)
var messageCache = new(sync.Map)
var networkcontext = new(sync.Map)
const lastNodeUpdate = "lnu"
const lastPeerUpdate = "lpu"
type cachedMessage struct {
Message string
LastSeen time.Time
}
// Daemon runs netclient daemon from command line
func Daemon() error {
UpdateClientConfig()
serverSet := make(map[string]bool)
// == initial pull of all networks ==
networks, _ := ncutils.GetSystemNetworks()
if len(networks) == 0 {
return errors.New("no networks")
}
pubNetworks = append(pubNetworks, networks...)
// set ipforwarding on startup
err := local.SetIPForwarding()
if err != nil {
logger.Log(0, err.Error())
}
for _, network := range networks {
logger.Log(3, "initializing network", network)
cfg := config.ClientConfig{}
cfg.Network = network
cfg.ReadConfig()
if err := wireguard.ApplyConf(&cfg.Node, cfg.Node.Interface, ncutils.GetNetclientPathSpecific()+cfg.Node.Interface+".conf"); err != nil {
logger.Log(0, "failed to start ", cfg.Node.Interface, "wg interface", err.Error())
}
server := cfg.Server.Server
if !serverSet[server] {
// == subscribe to all nodes for each on machine ==
serverSet[server] = true
logger.Log(1, "started daemon for server ", server)
ctx, cancel := context.WithCancel(context.Background())
networkcontext.Store(server, cancel)
go messageQueue(ctx, &cfg)
}
}
// == add waitgroup and cancel for checkin routine ==
wg := sync.WaitGroup{}
ctx, cancel := context.WithCancel(context.Background())
wg.Add(1)
go Checkin(ctx, &wg)
quit := make(chan os.Signal, 1)
signal.Notify(quit, syscall.SIGTERM, os.Interrupt)
<-quit
for server := range serverSet {
if cancel, ok := networkcontext.Load(server); ok {
cancel.(context.CancelFunc)()
}
}
cancel()
logger.Log(0, "shutting down netclient daemon")
wg.Wait()
logger.Log(0, "shutdown complete")
return nil
}
// UpdateKeys -- updates private key and returns new publickey
func UpdateKeys(nodeCfg *config.ClientConfig, client mqtt.Client) error {
logger.Log(0, "received message to update wireguard keys for network ", nodeCfg.Network)
key, err := wgtypes.GeneratePrivateKey()
if err != nil {
logger.Log(0, "error generating privatekey ", err.Error())
return err
}
file := ncutils.GetNetclientPathSpecific() + nodeCfg.Node.Interface + ".conf"
if err := wireguard.UpdatePrivateKey(file, key.String()); err != nil {
logger.Log(0, "error updating wireguard key ", err.Error())
return err
}
if storeErr := wireguard.StorePrivKey(key.String(), nodeCfg.Network); storeErr != nil {
logger.Log(0, "failed to save private key", storeErr.Error())
return storeErr
}
nodeCfg.Node.PublicKey = key.PublicKey().String()
PublishNodeUpdate(nodeCfg)
return nil
}
// == Private ==
// sets MQ client subscriptions for a specific node config
// should be called for each node belonging to a given server
func setSubscriptions(client mqtt.Client, nodeCfg *config.ClientConfig) {
if token := client.Subscribe(fmt.Sprintf("update/%s/%s", nodeCfg.Node.Network, nodeCfg.Node.ID), 0, mqtt.MessageHandler(NodeUpdate)); token.WaitTimeout(mq.MQ_TIMEOUT*time.Second) && token.Error() != nil {
if token.Error() == nil {
logger.Log(0, "connection timeout")
} else {
logger.Log(0, token.Error().Error())
}
return
}
logger.Log(3, fmt.Sprintf("subscribed to node updates for node %s update/%s/%s", nodeCfg.Node.Name, nodeCfg.Node.Network, nodeCfg.Node.ID))
if token := client.Subscribe(fmt.Sprintf("peers/%s/%s", nodeCfg.Node.Network, nodeCfg.Node.ID), 0, mqtt.MessageHandler(UpdatePeers)); token.Wait() && token.Error() != nil {
logger.Log(0, token.Error().Error())
return
}
logger.Log(3, fmt.Sprintf("subscribed to peer updates for node %s peers/%s/%s", nodeCfg.Node.Name, nodeCfg.Node.Network, nodeCfg.Node.ID))
}
// on a delete usually, pass in the nodecfg to unsubscribe client broker communications
// for the node in nodeCfg
func unsubscribeNode(client mqtt.Client, nodeCfg *config.ClientConfig) {
client.Unsubscribe(fmt.Sprintf("update/%s/%s", nodeCfg.Node.Network, nodeCfg.Node.ID))
var ok = true
if token := client.Unsubscribe(fmt.Sprintf("update/%s/%s", nodeCfg.Node.Network, nodeCfg.Node.ID)); token.WaitTimeout(mq.MQ_TIMEOUT*time.Second) && token.Error() != nil {
if token.Error() == nil {
logger.Log(1, "unable to unsubscribe from updates for node ", nodeCfg.Node.Name, "\n", "connection timeout")
} else {
logger.Log(1, "unable to unsubscribe from updates for node ", nodeCfg.Node.Name, "\n", token.Error().Error())
}
ok = false
}
if token := client.Unsubscribe(fmt.Sprintf("peers/%s/%s", nodeCfg.Node.Network, nodeCfg.Node.ID)); token.WaitTimeout(mq.MQ_TIMEOUT*time.Second) && token.Error() != nil {
if token.Error() == nil {
logger.Log(1, "unable to unsubscribe from peer updates for node ", nodeCfg.Node.Name, "\n", "connection timeout")
} else {
logger.Log(1, "unable to unsubscribe from peer updates for node ", nodeCfg.Node.Name, "\n", token.Error().Error())
}
ok = false
}
if ok {
logger.Log(1, "successfully unsubscribed node ", nodeCfg.Node.ID, " : ", nodeCfg.Node.Name)
}
}
// sets up Message Queue and subsribes/publishes updates to/from server
// the client should subscribe to ALL nodes that exist on server locally
func messageQueue(ctx context.Context, cfg *config.ClientConfig) {
logger.Log(0, "netclient daemon started for server: ", cfg.Server.Server)
client, err := setupMQTT(cfg, false)
if err != nil {
logger.Log(0, "unable to connect to broker", cfg.Server.Server, err.Error())
return
}
defer client.Disconnect(250)
<-ctx.Done()
logger.Log(0, "shutting down daemon for server ", cfg.Server.Server)
}
// NewTLSConf sets up tls configuration to connect to broker securely
func NewTLSConfig(server string) (*tls.Config, error) {
file := ncutils.GetNetclientServerPath(server) + ncutils.GetSeparator() + "root.pem"
certpool := x509.NewCertPool()
ca, err := os.ReadFile(file)
if err != nil {
logger.Log(0, "could not read CA file ", err.Error())
}
ok := certpool.AppendCertsFromPEM(ca)
if !ok {
logger.Log(0, "failed to append cert")
}
clientKeyPair, err := tls.LoadX509KeyPair(ncutils.GetNetclientServerPath(server)+ncutils.GetSeparator()+"client.pem", ncutils.GetNetclientPath()+ncutils.GetSeparator()+"client.key")
if err != nil {
logger.Log(0, "could not read client cert/key ", err.Error())
return nil, err
}
certs := []tls.Certificate{clientKeyPair}
return &tls.Config{
RootCAs: certpool,
ClientAuth: tls.NoClientCert,
ClientCAs: nil,
Certificates: certs,
InsecureSkipVerify: false,
}, nil
}
// setupMQTT creates a connection to broker and returns client
// this function is primarily used to create a connection to publish to the broker
func setupMQTT(cfg *config.ClientConfig, publish bool) (mqtt.Client, error) {
opts := mqtt.NewClientOptions()
server := cfg.Server.Server
port := cfg.Server.MQPort
opts.AddBroker("ssl://" + server + ":" + port)
tlsConfig, err := NewTLSConfig(server)
if err != nil {
logger.Log(0, "failed to get TLS config for", server, err.Error())
return nil, err
}
opts.SetTLSConfig(tlsConfig)
opts.SetClientID(ncutils.MakeRandomString(23))
opts.SetDefaultPublishHandler(All)
opts.SetAutoReconnect(true)
opts.SetConnectRetry(true)
opts.SetConnectRetryInterval(time.Second << 2)
opts.SetKeepAlive(time.Minute >> 1)
opts.SetWriteTimeout(time.Minute)
opts.SetOnConnectHandler(func(client mqtt.Client) {
if !publish {
networks, err := ncutils.GetSystemNetworks()
if err != nil {
logger.Log(0, "error retriving networks ", err.Error())
}
for _, network := range networks {
var currNodeCfg config.ClientConfig
currNodeCfg.Network = network
currNodeCfg.ReadConfig()
setSubscriptions(client, &currNodeCfg)
}
}
})
opts.SetOrderMatters(true)
opts.SetResumeSubs(true)
opts.SetConnectionLostHandler(func(c mqtt.Client, e error) {
logger.Log(0, "detected broker connection lost for", cfg.Server.Server)
})
client := mqtt.NewClient(opts)
for token := client.Connect(); !token.WaitTimeout(30*time.Second) || token.Error() != nil; token = client.Connect() {
logger.Log(0, "unable to connect to broker, retrying ...")
var err error
if token.Error() == nil {
err = errors.New("connect timeout")
} else {
err = token.Error()
}
if err := checkBroker(cfg.Server.Server, cfg.Server.MQPort); err != nil {
return nil, err
}
logger.Log(0, "could not connect to broker", cfg.Server.Server, err.Error())
if strings.Contains(err.Error(), "connectex") || strings.Contains(err.Error(), "connect timeout") {
reRegisterWithServer(cfg)
}
}
return client, nil
}
func reRegisterWithServer(cfg *config.ClientConfig) {
logger.Log(0, "connection issue detected.. attempt connection with new certs and broker information")
key, err := ssl.ReadKeyFromFile(ncutils.GetNetclientPath() + ncutils.GetSeparator() + "client.key")
if err != nil {
_, *key, err = ed25519.GenerateKey(rand.Reader)
if err != nil {
log.Fatal("could not generate new key")
}
}
RegisterWithServer(key, cfg)
daemon.Restart()
}
// publishes a message to server to update peers on this peer's behalf
func publishSignal(nodeCfg *config.ClientConfig, signal byte) error {
if err := publish(nodeCfg, fmt.Sprintf("signal/%s", nodeCfg.Node.ID), []byte{signal}, 1); err != nil {
return err
}
return nil
}
func parseNetworkFromTopic(topic string) string {
return strings.Split(topic, "/")[1]
}
// should only ever use node client configs
func decryptMsg(nodeCfg *config.ClientConfig, msg []byte) ([]byte, error) {
if len(msg) <= 24 { // make sure message is of appropriate length
return nil, fmt.Errorf("recieved invalid message from broker %v", msg)
}
// setup the keys
diskKey, keyErr := auth.RetrieveTrafficKey(nodeCfg.Node.Network)
if keyErr != nil {
return nil, keyErr
}
serverPubKey, err := ncutils.ConvertBytesToKey(nodeCfg.Node.TrafficKeys.Server)
if err != nil {
return nil, err
}
return ncutils.DeChunk(msg, serverPubKey, diskKey)
}
// == Message Caches ==
func insert(network, which, cache string) {
var newMessage = cachedMessage{
Message: cache,
LastSeen: time.Now(),
}
messageCache.Store(fmt.Sprintf("%s%s", network, which), newMessage)
}
func read(network, which string) string {
val, isok := messageCache.Load(fmt.Sprintf("%s%s", network, which))
if isok {
var readMessage = val.(cachedMessage) // fetch current cached message
if readMessage.LastSeen.IsZero() {
return ""
}
if time.Now().After(readMessage.LastSeen.Add(time.Hour * 24)) { // check if message has been there over a minute
messageCache.Delete(fmt.Sprintf("%s%s", network, which)) // remove old message if expired
return ""
}
return readMessage.Message // return current message if not expired
}
return ""
}