nebula/main.go

348 lines
10 KiB
Go

package nebula
import (
"encoding/binary"
"fmt"
"net"
"os"
"os/signal"
"strconv"
"strings"
"syscall"
"time"
"github.com/sirupsen/logrus"
"github.com/slackhq/nebula/sshd"
"gopkg.in/yaml.v2"
)
var l = logrus.New()
type m map[string]interface{}
func Main(configPath string, configTest bool, buildVersion string) {
l.Out = os.Stdout
l.Formatter = &logrus.TextFormatter{
FullTimestamp: true,
}
config := NewConfig()
err := config.Load(configPath)
if err != nil {
l.WithError(err).Error("Failed to load config")
os.Exit(1)
}
// Print the config if in test, the exit comes later
if configTest {
b, err := yaml.Marshal(config.Settings)
if err != nil {
l.Println(err)
os.Exit(1)
}
l.Println(string(b))
}
err = configLogger(config)
if err != nil {
l.WithError(err).Error("Failed to configure the logger")
}
config.RegisterReloadCallback(func(c *Config) {
err := configLogger(c)
if err != nil {
l.WithError(err).Error("Failed to configure the logger")
}
})
// trustedCAs is currently a global, so loadCA operates on that global directly
trustedCAs, err = loadCAFromConfig(config)
if err != nil {
//The errors coming out of loadCA are already nicely formatted
l.WithError(err).Fatal("Failed to load ca from config")
}
l.WithField("fingerprints", trustedCAs.GetFingerprints()).Debug("Trusted CA fingerprints")
cs, err := NewCertStateFromConfig(config)
if err != nil {
//The errors coming out of NewCertStateFromConfig are already nicely formatted
l.WithError(err).Fatal("Failed to load certificate from config")
}
l.WithField("cert", cs.certificate).Debug("Client nebula certificate")
fw, err := NewFirewallFromConfig(cs.certificate, config)
if err != nil {
l.WithError(err).Fatal("Error while loading firewall rules")
}
l.WithField("firewallHash", fw.GetRuleHash()).Info("Firewall started")
// TODO: make sure mask is 4 bytes
tunCidr := cs.certificate.Details.Ips[0]
routes, err := parseRoutes(config, tunCidr)
unsafeRoutes, err := parseUnsafeRoutes(config, tunCidr)
if err != nil {
l.WithError(err).Fatal("Could not parse tun.routes")
}
ssh, err := sshd.NewSSHServer(l.WithField("subsystem", "sshd"))
wireSSHReload(ssh, config)
if config.GetBool("sshd.enabled", false) {
err = configSSH(ssh, config)
if err != nil {
l.WithError(err).Fatal("Error while configuring the sshd")
}
}
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// All non system modifying configuration consumption should live above this line
// tun config, listeners, anything modifying the computer should be below
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
if configTest {
os.Exit(0)
}
config.CatchHUP()
// set up our tun dev
tun, err := newTun(
config.GetString("tun.dev", ""),
tunCidr,
config.GetInt("tun.mtu", 1300),
routes,
unsafeRoutes,
config.GetInt("tun.tx_queue", 500),
)
if err != nil {
l.WithError(err).Fatal("Failed to get a tun/tap device")
}
// set up our UDP listener
udpQueues := config.GetInt("listen.routines", 1)
udpServer, err := NewListener(config.GetString("listen.host", "0.0.0.0"), config.GetInt("listen.port", 0), udpQueues > 1)
if err != nil {
l.WithError(err).Fatal("Failed to open udp listener")
}
udpServer.reloadConfig(config)
// Set up my internal host map
var preferredRanges []*net.IPNet
rawPreferredRanges := config.GetStringSlice("preferred_ranges", []string{})
// First, check if 'preferred_ranges' is set and fallback to 'local_range'
if len(rawPreferredRanges) > 0 {
for _, rawPreferredRange := range rawPreferredRanges {
_, preferredRange, err := net.ParseCIDR(rawPreferredRange)
if err != nil {
l.WithError(err).Fatal("Failed to parse preferred ranges")
}
preferredRanges = append(preferredRanges, preferredRange)
}
}
// local_range was superseded by preferred_ranges. If it is still present,
// merge the local_range setting into preferred_ranges. We will probably
// deprecate local_range and remove in the future.
rawLocalRange := config.GetString("local_range", "")
if rawLocalRange != "" {
_, localRange, err := net.ParseCIDR(rawLocalRange)
if err != nil {
l.WithError(err).Fatal("Failed to parse local range")
}
// Check if the entry for local_range was already specified in
// preferred_ranges. Don't put it into the slice twice if so.
var found bool
for _, r := range preferredRanges {
if r.String() == localRange.String() {
found = true
break
}
}
if !found {
preferredRanges = append(preferredRanges, localRange)
}
}
hostMap := NewHostMap("main", tunCidr, preferredRanges)
hostMap.SetDefaultRoute(ip2int(net.ParseIP(config.GetString("default_route", "0.0.0.0"))))
hostMap.addUnsafeRoutes(&unsafeRoutes)
l.WithField("network", hostMap.vpnCIDR).WithField("preferredRanges", hostMap.preferredRanges).Info("Main HostMap created")
/*
config.SetDefault("promoter.interval", 10)
go hostMap.Promoter(config.GetInt("promoter.interval"))
*/
punchy := config.GetBool("punchy", false)
if punchy == true {
l.Info("UDP hole punching enabled")
go hostMap.Punchy(udpServer)
}
port := config.GetInt("listen.port", 0)
// If port is dynamic, discover it
if port == 0 {
uPort, err := udpServer.LocalAddr()
if err != nil {
l.WithError(err).Fatal("Failed to get listening port")
}
port = int(uPort.Port)
}
punchBack := config.GetBool("punch_back", false)
amLighthouse := config.GetBool("lighthouse.am_lighthouse", false)
// warn if am_lighthouse is enabled but upstream lighthouses exists
rawLighthouseHosts := config.GetStringSlice("lighthouse.hosts", []string{})
if amLighthouse && len(rawLighthouseHosts) != 0 {
l.Warn("lighthouse.am_lighthouse enabled on node but upstream lighthouses exist in config")
}
lighthouseHosts := make([]uint32, len(rawLighthouseHosts))
for i, host := range rawLighthouseHosts {
ip := net.ParseIP(host)
if ip == nil {
l.WithField("host", host).Fatalf("Unable to parse lighthouse host entry %v", i+1)
}
lighthouseHosts[i] = ip2int(ip)
}
lightHouse := NewLightHouse(
amLighthouse,
ip2int(tunCidr.IP),
lighthouseHosts,
//TODO: change to a duration
config.GetInt("lighthouse.interval", 10),
port,
udpServer,
punchBack,
)
//TODO: Move all of this inside functions in lighthouse.go
for k, v := range config.GetMap("static_host_map", map[interface{}]interface{}{}) {
vpnIp := net.ParseIP(fmt.Sprintf("%v", k))
vals, ok := v.([]interface{})
if ok {
for _, v := range vals {
parts := strings.Split(fmt.Sprintf("%v", v), ":")
addr, err := net.ResolveIPAddr("ip", parts[0])
if err == nil {
ip := addr.IP
port, err := strconv.Atoi(parts[1])
if err != nil {
l.Fatalf("Static host address for %s could not be parsed: %s", vpnIp, v)
}
lightHouse.AddRemote(ip2int(vpnIp), NewUDPAddr(ip2int(ip), uint16(port)), true)
}
}
} else {
//TODO: make this all a helper
parts := strings.Split(fmt.Sprintf("%v", v), ":")
addr, err := net.ResolveIPAddr("ip", parts[0])
if err == nil {
ip := addr.IP
port, err := strconv.Atoi(parts[1])
if err != nil {
l.Fatalf("Static host address for %s could not be parsed: %s", vpnIp, v)
}
lightHouse.AddRemote(ip2int(vpnIp), NewUDPAddr(ip2int(ip), uint16(port)), true)
}
}
}
err = lightHouse.ValidateLHStaticEntries()
if err != nil {
l.WithError(err).Error("Lighthouse unreachable")
}
handshakeManager := NewHandshakeManager(tunCidr, preferredRanges, hostMap, lightHouse, udpServer)
//TODO: These will be reused for psk
//handshakeMACKey := config.GetString("handshake_mac.key", "")
//handshakeAcceptedMACKeys := config.GetStringSlice("handshake_mac.accepted_keys", []string{})
serveDns := config.GetBool("lighthouse.serve_dns", false)
checkInterval := config.GetInt("timers.connection_alive_interval", 5)
pendingDeletionInterval := config.GetInt("timers.pending_deletion_interval", 10)
ifConfig := &InterfaceConfig{
HostMap: hostMap,
Inside: tun,
Outside: udpServer,
certState: cs,
Cipher: config.GetString("cipher", "aes"),
Firewall: fw,
ServeDns: serveDns,
HandshakeManager: handshakeManager,
lightHouse: lightHouse,
checkInterval: checkInterval,
pendingDeletionInterval: pendingDeletionInterval,
DropLocalBroadcast: config.GetBool("tun.drop_local_broadcast", false),
DropMulticast: config.GetBool("tun.drop_multicast", false),
UDPBatchSize: config.GetInt("listen.batch", 64),
}
switch ifConfig.Cipher {
case "aes":
noiseEndiannes = binary.BigEndian
case "chachapoly":
noiseEndiannes = binary.LittleEndian
default:
l.Fatalf("Unknown cipher: %v", ifConfig.Cipher)
}
ifce, err := NewInterface(ifConfig)
if err != nil {
l.WithError(err).Fatal("Failed to initialize interface")
}
ifce.RegisterConfigChangeCallbacks(config)
go handshakeManager.Run(ifce)
go lightHouse.LhUpdateWorker(ifce)
err = startStats(config)
if err != nil {
l.WithError(err).Fatal("Failed to start stats emitter")
}
//TODO: check if we _should_ be emitting stats
go ifce.emitStats(config.GetDuration("stats.interval", time.Second*10))
attachCommands(ssh, hostMap, handshakeManager.pendingHostMap, lightHouse, ifce)
ifce.Run(config.GetInt("tun.routines", 1), udpQueues, buildVersion)
// Start DNS server last to allow using the nebula IP as lighthouse.dns.host
if amLighthouse && serveDns {
l.Debugln("Starting dns server")
go dnsMain(hostMap, config)
}
// Just sit here and be friendly, main thread.
shutdownBlock(ifce)
}
func shutdownBlock(ifce *Interface) {
var sigChan = make(chan os.Signal)
signal.Notify(sigChan, syscall.SIGTERM)
signal.Notify(sigChan, syscall.SIGINT)
sig := <-sigChan
l.WithField("signal", sig).Info("Caught signal, shutting down")
//TODO: stop tun and udp routines, the lock on hostMap does effectively does that though
//TODO: this is probably better as a function in ConnectionManager or HostMap directly
ifce.hostMap.Lock()
for _, h := range ifce.hostMap.Hosts {
if h.ConnectionState.ready {
ifce.send(closeTunnel, 0, h.ConnectionState, h, h.remote, []byte{}, make([]byte, 12, 12), make([]byte, mtu))
l.WithField("vpnIp", IntIp(h.hostId)).WithField("udpAddr", h.remote).
Debug("Sending close tunnel message")
}
}
ifce.hostMap.Unlock()
l.WithField("signal", sig).Info("Goodbye")
os.Exit(0)
}