TUN-2606: add DialEdge helpers

connection/connection.go

@@ -2,7 +2,6 @@ package connection
 
 import (
 	"context"
-	"net"
 	"time"
 
 	"github.com/cloudflare/cloudflared/h2mux"
@@ -20,20 +19,12 @@ const (
 	openStreamTimeout = 30 * time.Second
 )
 
-type dialError struct {
-	cause error
-}
-
-func (e dialError) Error() string {
-	return e.cause.Error()
-}
-
 type Connection struct {
 	id    uuid.UUID
 	muxer *h2mux.Muxer
 }
 
-func newConnection(muxer *h2mux.Muxer, edgeIP *net.TCPAddr) (*Connection, error) {
+func newConnection(muxer *h2mux.Muxer) (*Connection, error) {
 	id, err := uuid.NewRandom()
 	if err != nil {
 		return nil, err

connection/dial.go

@@ -0,0 +1,54 @@
+package connection
+
+import (
+	"context"
+	"crypto/tls"
+	"net"
+	"time"
+
+	"github.com/pkg/errors"
+)
+
+// DialEdge makes a TLS connection to a Cloudflare edge node
+func DialEdge(
+	ctx context.Context,
+	timeout time.Duration,
+	tlsConfig *tls.Config,
+	edgeTCPAddr *net.TCPAddr,
+) (net.Conn, error) {
+	// Inherit from parent context so we can cancel (Ctrl-C) while dialing
+	dialCtx, dialCancel := context.WithTimeout(ctx, timeout)
+	defer dialCancel()
+
+	dialer := net.Dialer{}
+	edgeConn, err := dialer.DialContext(dialCtx, "tcp", edgeTCPAddr.String())
+	if err != nil {
+		return nil, newDialError(err, "DialContext error")
+	}
+	tlsEdgeConn := tls.Client(edgeConn, tlsConfig)
+	tlsEdgeConn.SetDeadline(time.Now().Add(timeout))
+
+	if err = tlsEdgeConn.Handshake(); err != nil {
+		return nil, newDialError(err, "Handshake with edge error")
+	}
+	// clear the deadline on the conn; h2mux has its own timeouts
+	tlsEdgeConn.SetDeadline(time.Time{})
+	return tlsEdgeConn, nil
+}
+
+// DialError is an error returned from DialEdge
+type DialError struct {
+	cause error
+}
+
+func newDialError(err error, message string) error {
+	return DialError{cause: errors.Wrap(err, message)}
+}
+
+func (e DialError) Error() string {
+	return e.cause.Error()
+}
+
+func (e DialError) Cause() error {
+	return e.cause
+}

connection/manager.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"crypto/tls"
 	"fmt"
-	"net"
 	"sync"
 	"time"
 
@@ -128,12 +127,12 @@ func (em *EdgeManager) UpdateConfigurable(newConfigurable *EdgeManagerConfigurab
 }
 
 func (em *EdgeManager) newConnection(ctx context.Context) *pogs.ConnectError {
-	edgeIP := em.serviceDiscoverer.Addr()
-	edgeConn, err := em.dialEdge(ctx, edgeIP)
+	edgeTCPAddr := em.serviceDiscoverer.Addr()
+	configurable := em.state.getConfigurable()
+	edgeConn, err := DialEdge(ctx, configurable.Timeout, em.tlsConfig, edgeTCPAddr)
 	if err != nil {
 		return retryConnection(fmt.Sprintf("dial edge error: %v", err))
 	}
-	configurable := em.state.getConfigurable()
 	// Establish a muxed connection with the edge
 	// Client mux handshake with agent server
 	muxer, err := h2mux.Handshake(edgeConn, edgeConn, h2mux.MuxerConfig{
@@ -148,7 +147,7 @@ func (em *EdgeManager) newConnection(ctx context.Context) *pogs.ConnectError {
 		retryConnection(fmt.Sprintf("couldn't perform handshake with edge: %v", err))
 	}
 
-	h2muxConn, err := newConnection(muxer, edgeIP)
+	h2muxConn, err := newConnection(muxer)
 	if err != nil {
 		return retryConnection(fmt.Sprintf("couldn't create h2mux connection: %v", err))
 	}
@@ -196,28 +195,6 @@ func (em *EdgeManager) serveConn(ctx context.Context, conn *Connection) {
 	em.state.closeConnection(conn)
 }
 
-func (em *EdgeManager) dialEdge(ctx context.Context, edgeIP *net.TCPAddr) (*tls.Conn, error) {
-	timeout := em.state.getConfigurable().Timeout
-	// Inherit from parent context so we can cancel (Ctrl-C) while dialing
-	dialCtx, dialCancel := context.WithTimeout(ctx, timeout)
-	defer dialCancel()
-
-	dialer := net.Dialer{}
-	edgeConn, err := dialer.DialContext(dialCtx, "tcp", edgeIP.String())
-	if err != nil {
-		return nil, dialError{cause: errors.Wrap(err, "DialContext error")}
-	}
-	tlsEdgeConn := tls.Client(edgeConn, em.tlsConfig)
-	tlsEdgeConn.SetDeadline(time.Now().Add(timeout))
-
-	if err = tlsEdgeConn.Handshake(); err != nil {
-		return nil, dialError{cause: errors.Wrap(err, "Handshake with edge error")}
-	}
-	// clear the deadline on the conn; h2mux has its own timeouts
-	tlsEdgeConn.SetDeadline(time.Time{})
-	return tlsEdgeConn, nil
-}
-
 func (em *EdgeManager) noRetryMessage() string {
 	messageTemplate := "cloudflared could not register an Argo Tunnel on your account. Please confirm the following before trying again:" +
 		"1. You have Argo Smart Routing enabled in your account, See Enable Argo section of %s." +

go.mod

@@ -57,6 +57,7 @@ require (
 	golang.org/x/sync v0.0.0-20190423024810-112230192c58
 	golang.org/x/sys v0.0.0-20191008105621-543471e840be
 	golang.org/x/text v0.3.2 // indirect
+	google.golang.org/appengine v1.4.0 // indirect
 	google.golang.org/genproto v0.0.0-20191007204434-a023cd5227bd // indirect
 	google.golang.org/grpc v1.24.0 // indirect
 	gopkg.in/coreos/go-oidc.v2 v2.1.0

origin/supervisor.go

@@ -183,7 +183,7 @@ func (s *Supervisor) startFirstTunnel(ctx context.Context, connectedSignal *sign
 			return
 		// try the next address if it was a dialError(network problem) or
 		// dupConnRegisterTunnelError
-		case dialError, dupConnRegisterTunnelError:
+		case connection.DialError, dupConnRegisterTunnelError:
 			s.replaceEdgeIP(0)
 		default:
 			return

origin/tunnel.go

@@ -15,6 +15,7 @@ import (
 	"time"
 
 	"github.com/cloudflare/cloudflared/cmd/cloudflared/buildinfo"
+	"github.com/cloudflare/cloudflared/connection"
 	"github.com/cloudflare/cloudflared/h2mux"
 	"github.com/cloudflare/cloudflared/signal"
 	"github.com/cloudflare/cloudflared/streamhandler"
@@ -27,7 +28,6 @@ import (
 	"github.com/google/uuid"
 	"github.com/pkg/errors"
 	"github.com/prometheus/client_golang/prometheus"
-	_ "github.com/prometheus/client_golang/prometheus"
 	log "github.com/sirupsen/logrus"
 	"golang.org/x/sync/errgroup"
 	rpc "zombiezen.com/go/capnproto2/rpc"
@@ -76,14 +76,6 @@ type TunnelConfig struct {
 	OriginUrl string
 }
 
-type dialError struct {
-	cause error
-}
-
-func (e dialError) Error() string {
-	return e.cause.Error()
-}
-
 type dupConnRegisterTunnelError struct{}
 
 func (e dupConnRegisterTunnelError) Error() string {
@@ -214,11 +206,11 @@ func ServeTunnel(
 	tags["ha"] = connectionTag
 
 	// Returns error from parsing the origin URL or handshake errors
-	handler, originLocalIP, err := NewTunnelHandler(ctx, config, addr.String(), connectionID)
+	handler, originLocalIP, err := NewTunnelHandler(ctx, config, addr, connectionID)
 	if err != nil {
 		errLog := logger.WithError(err)
 		switch err.(type) {
-		case dialError:
+		case connection.DialError:
 			errLog.Error("Unable to dial edge")
 		case h2mux.MuxerHandshakeError:
 			errLog.Error("Handshake failed with edge server")
@@ -470,7 +462,7 @@ var dialer = net.Dialer{}
 // NewTunnelHandler returns a TunnelHandler, origin LAN IP and error
 func NewTunnelHandler(ctx context.Context,
 	config *TunnelConfig,
-	addr string,
+	addr *net.TCPAddr,
 	connectionID uint8,
 ) (*TunnelHandler, string, error) {
 	originURL, err := validation.ValidateUrl(config.OriginUrl)
@@ -491,22 +483,11 @@ func NewTunnelHandler(ctx context.Context,
 	if h.httpClient == nil {
 		h.httpClient = http.DefaultTransport
 	}
-	// Inherit from parent context so we can cancel (Ctrl-C) while dialing
-	dialCtx, dialCancel := context.WithTimeout(ctx, dialTimeout)
-	// TUN-92: enforce a timeout on dial and handshake (as tls.Dial does not support one)
-	plaintextEdgeConn, err := dialer.DialContext(dialCtx, "tcp", addr)
-	dialCancel()
+
+	edgeConn, err := connection.DialEdge(ctx, dialTimeout, config.TlsConfig, addr)
 	if err != nil {
-		return nil, "", dialError{cause: errors.Wrap(err, "DialContext error")}
+		return nil, "", err
 	}
-	edgeConn := tls.Client(plaintextEdgeConn, config.TlsConfig)
-	edgeConn.SetDeadline(time.Now().Add(dialTimeout))
-	err = edgeConn.Handshake()
-	if err != nil {
-		return nil, "", dialError{cause: errors.Wrap(err, "Handshake with edge error")}
-	}
-	// clear the deadline on the conn; h2mux has its own timeouts
-	edgeConn.SetDeadline(time.Time{})
 	// Establish a muxed connection with the edge
 	// Client mux handshake with agent server
 	h.muxer, err = h2mux.Handshake(edgeConn, edgeConn, h2mux.MuxerConfig{
@@ -519,9 +500,9 @@ func NewTunnelHandler(ctx context.Context,
 		CompressionQuality: h2mux.CompressionSetting(config.CompressionQuality),
 	}, h.metrics.activeStreams)
 	if err != nil {
-		return h, "", errors.New("TLS handshake error")
+		return nil, "", errors.Wrap(err, "Handshake with edge error")
 	}
-	return h, edgeConn.LocalAddr().String(), err
+	return h, edgeConn.LocalAddr().String(), nil
 }
 
 func (h *TunnelHandler) AppendTagHeaders(r *http.Request) {