Files
newt/newt/connect.go
T

352 lines
10 KiB
Go

package newt
import (
"context"
"encoding/json"
"fmt"
"net"
"net/netip"
"runtime"
"time"
"github.com/fosrl/newt/browsergateway"
newtDevice "github.com/fosrl/newt/device"
"github.com/fosrl/newt/internal/telemetry"
"github.com/fosrl/newt/logger"
"github.com/fosrl/newt/network"
"github.com/fosrl/newt/proxy"
"github.com/fosrl/newt/util"
"github.com/fosrl/newt/websocket"
"golang.zx2c4.com/wireguard/conn"
"golang.zx2c4.com/wireguard/device"
wtun "golang.zx2c4.com/wireguard/tun"
"golang.zx2c4.com/wireguard/tun/netstack"
)
func (n *Newt) handleConnect(ctx context.Context, msg websocket.WSMessage) {
logger.Debug("Received registration message")
regResult := "success"
defer func() {
telemetry.IncSiteRegistration(ctx, regResult)
}()
var chainData struct {
ChainId string `json:"chainId"`
}
if jsonBytes, err := json.Marshal(msg.Data); err == nil {
_ = json.Unmarshal(jsonBytes, &chainData)
}
if chainData.ChainId != "" {
if chainData.ChainId != n.pendingRegisterChainId {
logger.Debug("Discarding duplicate/stale newt/wg/connect (chainId=%s, expected=%s)", chainData.ChainId, n.pendingRegisterChainId)
return
}
n.pendingRegisterChainId = ""
}
if n.stopFunc != nil {
n.stopFunc()
n.stopFunc = nil
}
if n.connected {
n.closeWgTunnel()
n.connected = false
}
logger.Debug("Received registration message data: %+v", msg.Data)
jsonData, err := json.Marshal(msg.Data)
if err != nil {
logger.Info(fmtErrMarshaling, err)
regResult = "failure"
return
}
if err := json.Unmarshal(jsonData, &n.wgData); err != nil {
logger.Info("Error unmarshaling target data: %v", err)
regResult = "failure"
return
}
logger.Debug(fmtReceivedMsg, msg)
if n.config.UseNativeMainInterface {
mainIfName := n.config.NativeMainInterfaceName
if runtime.GOOS == "darwin" {
mainIfName, err = network.FindUnusedUTUN()
if err != nil {
logger.Error("Failed to find unused utun for main tunnel: %v", err)
regResult = "failure"
return
}
}
n.tun, err = wtun.CreateTUN(mainIfName, n.config.MTU)
if err != nil {
logger.Error("Failed to create native main TUN device: %v", err)
regResult = "failure"
return
}
if realName, nameErr := n.tun.Name(); nameErr == nil {
mainIfName = realName
}
n.tnet = nil
n.config.NativeMainInterfaceName = mainIfName
} else {
n.tun, n.tnet, err = netstack.CreateNetTUN(
[]netip.Addr{netip.MustParseAddr(n.wgData.TunnelIP)},
[]netip.Addr{netip.MustParseAddr(n.config.DNS)},
n.config.MTU)
if err != nil {
logger.Error("Failed to create TUN device: %v", err)
regResult = "failure"
}
}
n.setDownstreamTNetstack(n.tnet)
n.dev = device.NewDevice(n.tun, conn.NewDefaultBind(), device.NewLogger(
util.MapToWireGuardLogLevel(n.loggerLevel),
"gerbil-wireguard: ",
))
host, _, err := net.SplitHostPort(n.wgData.Endpoint)
if err != nil {
logger.Error("Failed to split endpoint: %v", err)
regResult = "failure"
return
}
logger.Info("Connecting to endpoint: %s", host)
resolvedEndpoint, err := util.ResolveDomain(n.wgData.Endpoint)
if err != nil {
logger.Error("Failed to resolve endpoint: %v", err)
regResult = "failure"
return
}
relayPort := n.wgData.RelayPort
if relayPort == 0 {
relayPort = 21820
}
n.clientsHandleNewtConnection(n.wgData.PublicKey, resolvedEndpoint, relayPort)
wgConfig := fmt.Sprintf(`private_key=%s
public_key=%s
allowed_ip=%s/32
endpoint=%s
persistent_keepalive_interval=5`, util.FixKey(n.privateKey.String()), util.FixKey(n.wgData.PublicKey), n.wgData.ServerIP, resolvedEndpoint)
if err = n.dev.IpcSet(wgConfig); err != nil {
logger.Error("Failed to configure WireGuard device: %v", err)
regResult = "failure"
}
if err = n.dev.Up(); err != nil {
logger.Error("Failed to bring up WireGuard device: %v", err)
regResult = "failure"
}
if n.config.UseNativeMainInterface {
if cfgErr := network.ConfigureInterface(n.config.NativeMainInterfaceName, n.wgData.TunnelIP+"/32", n.config.MTU); cfgErr != nil {
logger.Error("Failed to configure native main tunnel interface: %v", cfgErr)
}
if routeErr := network.AddRoutes([]string{n.wgData.ServerIP + "/32"}, n.config.NativeMainInterfaceName); routeErr != nil {
logger.Warn("Failed to add route for main tunnel server IP: %v", routeErr)
}
if fileUAPI, uapiErr := newtDevice.UapiOpen(n.config.NativeMainInterfaceName); uapiErr != nil {
logger.Warn("Main tunnel UAPI open error: %v", uapiErr)
} else if uapiListener, uapiListenErr := newtDevice.UapiListen(n.config.NativeMainInterfaceName, fileUAPI); uapiListenErr != nil {
logger.Warn("Main tunnel UAPI listen error: %v", uapiListenErr)
} else {
go func() {
for {
c, aErr := uapiListener.Accept()
if aErr != nil {
return
}
go n.dev.IpcHandle(c)
}
}()
logger.Debug("Main tunnel UAPI listener started on %s", n.config.NativeMainInterfaceName)
}
}
n.activeRemoteSubnets = nil
if len(n.wgData.RemoteExitNodeSubnets) > 0 {
for _, subnet := range n.wgData.RemoteExitNodeSubnets {
subnetCfg := fmt.Sprintf("public_key=%s\nallowed_ip=%s", util.FixKey(n.wgData.PublicKey), subnet)
if err := n.dev.IpcSet(subnetCfg); err != nil {
logger.Warn("Failed to add AllowedIP %s to main tunnel: %v", subnet, err)
}
}
if n.config.UseNativeMainInterface {
if routeErr := network.AddRoutes(n.wgData.RemoteExitNodeSubnets, n.config.NativeMainInterfaceName); routeErr != nil {
logger.Warn("Failed to add routes for remote exit node subnets: %v", routeErr)
}
}
n.activeRemoteSubnets = append([]string{}, n.wgData.RemoteExitNodeSubnets...)
logger.Debug("Added %d remote exit node subnets", len(n.wgData.RemoteExitNodeSubnets))
}
logger.Debug("WireGuard device created. Lets ping the server now...")
if n.pingWithRetryStopChan != nil {
close(n.pingWithRetryStopChan)
n.pingWithRetryStopChan = nil
}
var pinger pingFunc
if n.config.UseNativeMainInterface {
pinger = pingNative
} else {
pinger = func(dst string, timeout time.Duration) (time.Duration, error) {
return ping(n.tnet, dst, timeout)
}
}
logger.Debug("Testing initial connection with reliable ping...")
lat, err := reliablePing(pinger, n.wgData.ServerIP, n.config.PingTimeout, 5)
if err == nil && n.wgData.PublicKey != "" {
telemetry.ObserveTunnelLatency(ctx, n.wgData.PublicKey, "wireguard", lat.Seconds())
}
if err != nil {
logger.Warn("Initial reliable ping failed, but continuing: %v", err)
regResult = "failure"
} else {
logger.Debug("Initial connection test successful")
}
n.pingWithRetryStopChan, _ = n.pingWithRetry(pinger, n.wgData.ServerIP, n.config.PingTimeout)
if !n.connected {
logger.Debug("Starting ping check")
n.pingStopChan = n.startPingCheck(pinger, n.wgData.ServerIP, n.wgData.PublicKey)
}
if n.config.UseNativeMainInterface {
n.pm = proxy.NewProxyManagerNative(n.wgData.TunnelIP)
} else {
n.pm = proxy.NewProxyManager(n.tnet)
}
n.pm.SetAsyncBytes(n.config.MetricsAsyncBytes)
n.pm.SetUDPIdleTimeout(n.config.UDPProxyIdleTimeout)
n.pm.SetTunnelID(n.wgData.PublicKey)
n.pm.SetBlocked(n.connectionBlocked.Load())
n.currentPM.Store(n.pm)
n.connected = true
if len(n.wgData.Targets.TCP) > 0 {
n.updateTargets(n.pm, "add", n.wgData.TunnelIP, "tcp", TargetData{Targets: n.wgData.Targets.TCP})
}
if len(n.wgData.Targets.UDP) > 0 {
n.updateTargets(n.pm, "add", n.wgData.TunnelIP, "udp", TargetData{Targets: n.wgData.Targets.UDP})
}
if !n.config.UseNativeMainInterface {
n.clientsStartDirectRelay(n.wgData.TunnelIP)
}
if err := n.healthMonitor.AddTargets(n.wgData.HealthCheckTargets); err != nil {
logger.Error("Failed to bulk add health check targets: %v", err)
} else {
logger.Debug("Successfully added %d health check targets", len(n.wgData.HealthCheckTargets))
}
if err = n.pm.Start(); err != nil {
logger.Error("Failed to start proxy manager: %v", err)
}
if len(n.wgData.BrowserGatewayTargets) > 0 {
// The netstack is fresh on (re)connect, so any previously running
// gateway listener is bound to a now-defunct interface - tear it down.
if n.browserGatewayStop != nil {
n.browserGatewayStop()
n.browserGatewayStop = nil
n.browserGateway = nil
}
if err := n.startBrowserGateway(); err != nil {
logger.Error("Failed to start browser gateway listener: %v", err)
} else {
n.browserGateway.SetTargets(toBrowserGatewayTargets(n.wgData.BrowserGatewayTargets))
}
}
}
// startBrowserGateway creates the browser gateway and its listener if one
// isn't already running. Callers that need to rebind to a fresh netstack
// (e.g. on reconnect) must stop and clear any existing gateway first.
func (n *Newt) startBrowserGateway() error {
if n.browserGateway != nil {
return nil
}
if n.tnet == nil && !n.config.UseNativeMainInterface {
return fmt.Errorf("netstack not ready")
}
gateway := browsergateway.New(browsergateway.Config{SSHCredentials: n.sshCredStore})
var ln net.Listener
var err error
if n.config.UseNativeMainInterface {
ln, err = net.Listen("tcp", fmt.Sprintf("%s:%d", n.wgData.TunnelIP, browsergateway.ListenPort))
} else {
ln, err = n.tnet.ListenTCP(&net.TCPAddr{Port: browsergateway.ListenPort})
}
if err != nil {
return err
}
n.browserGateway = gateway
n.browserGatewayStop = func() { _ = ln.Close() }
go func() {
logger.Debug("Browser gateway started on port %d", browsergateway.ListenPort)
if startErr := gateway.Start(ln); startErr != nil {
logger.Error("Browser gateway stopped with error: %v", startErr)
}
}()
return nil
}
// syncBrowserGatewayTargets reconciles the browser gateway's allowed
// destinations with the desired state received from a sync message.
// It lazily starts the gateway if targets are present and it isn't running
// yet, and clears the allow-list (without tearing down the listener) when
// no targets are desired.
func (n *Newt) syncBrowserGatewayTargets(targets []BrowserGatewayTarget) {
bgTargets := toBrowserGatewayTargets(targets)
if len(bgTargets) == 0 {
if n.browserGateway != nil {
n.browserGateway.SetTargets(nil)
}
return
}
if err := n.startBrowserGateway(); err != nil {
logger.Error("Failed to start browser gateway: %v", err)
return
}
n.browserGateway.SetTargets(bgTargets)
}
func toBrowserGatewayTargets(targets []BrowserGatewayTarget) []browsergateway.Target {
bgTargets := make([]browsergateway.Target, 0, len(targets))
for _, t := range targets {
bgTargets = append(bgTargets, browsergateway.Target{
ID: t.ID,
Type: t.Type,
Destination: t.Destination,
DestinationPort: t.DestinationPort,
AuthToken: t.AuthToken,
})
}
return bgTargets
}