Merge pull request #1286 from tendermint/feature/xla-priv-val-invert-dial

Invert privVal socket communication

cmd/priv_val_server/main.go

@@ -12,36 +12,41 @@ import (
 
 func main() {
 	var (
+		addr        = flag.String("addr", ":46659", "Address of client to connect to")
 		chainID     = flag.String("chain-id", "mychain", "chain id")
-		listenAddr  = flag.String("laddr", ":46659", "Validator listen address (0.0.0.0:0 means any interface, any port")
-		maxConn     = flag.Int("clients", 3, "maximum of concurrent connections")
 		privValPath = flag.String("priv", "", "priv val file path")
 
-		logger = log.NewTMLogger(log.NewSyncWriter(os.Stdout)).With("module", "priv_val")
+		logger = log.NewTMLogger(
+			log.NewSyncWriter(os.Stdout),
+		).With("module", "priv_val")
 	)
 	flag.Parse()
 
 	logger.Info(
 		"Starting private validator",
+		"addr", *addr,
 		"chainID", *chainID,
-		"listenAddr", *listenAddr,
-		"maxConn", *maxConn,
 		"privPath", *privValPath,
 	)
 
 	privVal := priv_val.LoadPrivValidatorJSON(*privValPath)
 
-	pvss := priv_val.NewPrivValidatorSocketServer(
+	rs := priv_val.NewRemoteSigner(
 		logger,
 		*chainID,
-		*listenAddr,
-		*maxConn,
+		*addr,
 		privVal,
 		nil,
 	)
-	pvss.Start()
+	err := rs.Start()
+	if err != nil {
+		panic(err)
+	}
 
 	cmn.TrapSignal(func() {
-		pvss.Stop()
+		err := rs.Stop()
+		if err != nil {
+			panic(err)
+		}
 	})
 }

types/priv_validator/socket.go

@@ -19,12 +19,16 @@ import (
 
 const (
 	defaultConnDeadlineSeconds = 3
-	defaultDialRetryMax        = 10
+	defaultConnWaitSeconds     = 60
+	defaultDialRetries         = 10
+	defaultSignersMax          = 1
 )
 
 // Socket errors.
 var (
-	ErrDialRetryMax = errors.New("Error max client retries")
+	ErrDialRetryMax    = errors.New("Error max client retries")
+	ErrConnWaitTimeout = errors.New("Error waiting for external connection")
+	ErrConnTimeout     = errors.New("Error connection timed out")
 )
 
 var (
@@ -34,10 +38,16 @@ var (
 // SocketClientOption sets an optional parameter on the SocketClient.
 type SocketClientOption func(*SocketClient)
 
-// SocketClientTimeout sets the timeout for connecting to the external socket
-// address.
-func SocketClientTimeout(timeout time.Duration) SocketClientOption {
-	return func(sc *SocketClient) { sc.connectTimeout = timeout }
+// SocketClientConnDeadline sets the read and write deadline for connections
+// from external signing processes.
+func SocketClientConnDeadline(deadline time.Duration) SocketClientOption {
+	return func(sc *SocketClient) { sc.connDeadline = deadline }
+}
+
+// SocketClientConnWait sets the timeout duration before connection of external
+// signing processes are considered to be unsuccessful.
+func SocketClientConnWait(timeout time.Duration) SocketClientOption {
+	return func(sc *SocketClient) { sc.connWaitTimeout = timeout }
 }
 
 // SocketClient implements PrivValidator, it uses a socket to request signatures
@@ -45,11 +55,13 @@ func SocketClientTimeout(timeout time.Duration) SocketClientOption {
 type SocketClient struct {
 	cmn.BaseService
 
-	conn    net.Conn
-	privKey *crypto.PrivKeyEd25519
+	addr            string
+	connDeadline    time.Duration
+	connWaitTimeout time.Duration
+	privKey         *crypto.PrivKeyEd25519
 
-	addr           string
-	connectTimeout time.Duration
+	conn     net.Conn
+	listener net.Listener
 }
 
 // Check that SocketClient implements PrivValidator2.
@@ -62,24 +74,37 @@ func NewSocketClient(
 	privKey *crypto.PrivKeyEd25519,
 ) *SocketClient {
 	sc := &SocketClient{
-		addr:           socketAddr,
-		connectTimeout: time.Second * defaultConnDeadlineSeconds,
-		privKey:        privKey,
+		addr:            socketAddr,
+		connDeadline:    time.Second * defaultConnDeadlineSeconds,
+		connWaitTimeout: time.Second * defaultConnWaitSeconds,
+		privKey:         privKey,
 	}
 
-	sc.BaseService = *cmn.NewBaseService(logger, "privValidatorSocketClient", sc)
+	sc.BaseService = *cmn.NewBaseService(logger, "SocketClient", sc)
 
 	return sc
 }
 
 // OnStart implements cmn.Service.
 func (sc *SocketClient) OnStart() error {
-	if err := sc.BaseService.OnStart(); err != nil {
-		return err
+	if sc.listener == nil {
+		if err := sc.listen(); err != nil {
+			sc.Logger.Error(
+				"OnStart",
+				"err", errors.Wrap(err, "failed to listen"),
+			)
+
+			return err
+		}
 	}
 
-	conn, err := sc.connect()
+	conn, err := sc.waitConnection()
 	if err != nil {
+		sc.Logger.Error(
+			"OnStart",
+			"err", errors.Wrap(err, "failed to accept connection"),
+		)
+
 		return err
 	}
 
@@ -93,7 +118,21 @@ func (sc *SocketClient) OnStop() {
 	sc.BaseService.OnStop()
 
 	if sc.conn != nil {
-		sc.conn.Close()
+		if err := sc.conn.Close(); err != nil {
+			sc.Logger.Error(
+				"OnStop",
+				"err", errors.Wrap(err, "failed to close connection"),
+			)
+		}
+	}
+
+	if sc.listener != nil {
+		if err := sc.listener.Close(); err != nil {
+			sc.Logger.Error(
+				"OnStop",
+				"err", errors.Wrap(err, "failed to close listener"),
+			)
+		}
 	}
 }
 
@@ -162,7 +201,10 @@ func (sc *SocketClient) SignVote(chainID string, vote *types.Vote) error {
 }
 
 // SignProposal implements PrivValidator2.
-func (sc *SocketClient) SignProposal(chainID string, proposal *types.Proposal) error {
+func (sc *SocketClient) SignProposal(
+	chainID string,
+	proposal *types.Proposal,
+) error {
 	err := writeMsg(sc.conn, &SignProposalMsg{Proposal: proposal})
 	if err != nil {
 		return err
@@ -179,7 +221,10 @@ func (sc *SocketClient) SignProposal(chainID string, proposal *types.Proposal) e
 }
 
 // SignHeartbeat implements PrivValidator2.
-func (sc *SocketClient) SignHeartbeat(chainID string, heartbeat *types.Heartbeat) error {
+func (sc *SocketClient) SignHeartbeat(
+	chainID string,
+	heartbeat *types.Heartbeat,
+) error {
 	err := writeMsg(sc.conn, &SignHeartbeatMsg{Heartbeat: heartbeat})
 	if err != nil {
 		return err
@@ -195,22 +240,164 @@ func (sc *SocketClient) SignHeartbeat(chainID string, heartbeat *types.Heartbeat
 	return nil
 }
 
-func (sc *SocketClient) connect() (net.Conn, error) {
-	retries := defaultDialRetryMax
+func (sc *SocketClient) acceptConnection() (net.Conn, error) {
+	conn, err := sc.listener.Accept()
+	if err != nil {
+		if !sc.IsRunning() {
+			return nil, nil // Ignore error from listener closing.
+		}
+		return nil, err
+
+	}
+
+	if err := conn.SetDeadline(time.Now().Add(sc.connDeadline)); err != nil {
+		return nil, err
+	}
+
+	if sc.privKey != nil {
+		conn, err = p2pconn.MakeSecretConnection(conn, sc.privKey.Wrap())
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	return conn, nil
+}
+
+func (sc *SocketClient) listen() error {
+	ln, err := net.Listen(cmn.ProtocolAndAddress(sc.addr))
+	if err != nil {
+		return err
+	}
+
+	sc.listener = netutil.LimitListener(ln, defaultSignersMax)
+
+	return nil
+}
+
+// waitConnection uses the configured wait timeout to error if no external
+// process connects in the time period.
+func (sc *SocketClient) waitConnection() (net.Conn, error) {
+	var (
+		connc = make(chan net.Conn, 1)
+		errc  = make(chan error, 1)
+	)
+
+	go func(connc chan<- net.Conn, errc chan<- error) {
+		conn, err := sc.acceptConnection()
+		if err != nil {
+			errc <- err
+			return
+		}
+
+		connc <- conn
+	}(connc, errc)
+
+	select {
+	case conn := <-connc:
+		return conn, nil
+	case err := <-errc:
+		return nil, err
+	case <-time.After(sc.connWaitTimeout):
+		return nil, ErrConnWaitTimeout
+	}
+}
+
+//---------------------------------------------------------
+
+// RemoteSignerOption sets an optional parameter on the RemoteSigner.
+type RemoteSignerOption func(*RemoteSigner)
+
+// RemoteSignerConnDeadline sets the read and write deadline for connections
+// from external signing processes.
+func RemoteSignerConnDeadline(deadline time.Duration) RemoteSignerOption {
+	return func(ss *RemoteSigner) { ss.connDeadline = deadline }
+}
+
+// RemoteSignerConnRetries sets the amount of attempted retries to connect.
+func RemoteSignerConnRetries(retries int) RemoteSignerOption {
+	return func(ss *RemoteSigner) { ss.connRetries = retries }
+}
+
+// RemoteSigner implements PrivValidator.
+// It responds to requests over a socket
+type RemoteSigner struct {
+	cmn.BaseService
+
+	addr         string
+	chainID      string
+	connDeadline time.Duration
+	connRetries  int
+	privKey      *crypto.PrivKeyEd25519
+	privVal      PrivValidator
+
+	conn net.Conn
+}
+
+// NewRemoteSigner returns an instance of
+// RemoteSigner.
+func NewRemoteSigner(
+	logger log.Logger,
+	chainID, socketAddr string,
+	privVal PrivValidator,
+	privKey *crypto.PrivKeyEd25519,
+) *RemoteSigner {
+	rs := &RemoteSigner{
+		addr:         socketAddr,
+		chainID:      chainID,
+		connDeadline: time.Second * defaultConnDeadlineSeconds,
+		connRetries:  defaultDialRetries,
+		privKey:      privKey,
+		privVal:      privVal,
+	}
+
+	rs.BaseService = *cmn.NewBaseService(logger, "RemoteSigner", rs)
+
+	return rs
+}
+
+// OnStart implements cmn.Service.
+func (rs *RemoteSigner) OnStart() error {
+	conn, err := rs.connect()
+	if err != nil {
+		rs.Logger.Error("OnStart", "err", errors.Wrap(err, "connect"))
+
+		return err
+	}
+
+	go rs.handleConnection(conn)
+
+	return nil
+}
+
+// OnStop implements cmn.Service.
+func (rs *RemoteSigner) OnStop() {
+	if rs.conn == nil {
+		return
+	}
+
+	if err := rs.conn.Close(); err != nil {
+		rs.Logger.Error("OnStop", "err", errors.Wrap(err, "closing listener failed"))
+	}
+}
+
+func (rs *RemoteSigner) connect() (net.Conn, error) {
+	retries := defaultDialRetries
 
 RETRY_LOOP:
 	for retries > 0 {
-		if retries != defaultDialRetryMax {
-			time.Sleep(sc.connectTimeout)
+		// Don't sleep if it is the first retry.
+		if retries != defaultDialRetries {
+			time.Sleep(rs.connDeadline)
 		}
 
 		retries--
 
-		conn, err := cmn.Connect(sc.addr)
+		conn, err := cmn.Connect(rs.addr)
 		if err != nil {
-			sc.Logger.Error(
-				"sc connect",
-				"addr", sc.addr,
+			rs.Logger.Error(
+				"connect",
+				"addr", rs.addr,
 				"err", errors.Wrap(err, "connection failed"),
 			)
 
@@ -218,17 +405,17 @@ RETRY_LOOP:
 		}
 
 		if err := conn.SetDeadline(time.Now().Add(connDeadline)); err != nil {
-			sc.Logger.Error(
-				"sc connect",
+			rs.Logger.Error(
+				"connect",
 				"err", errors.Wrap(err, "setting connection timeout failed"),
 			)
 			continue
 		}
 
-		if sc.privKey != nil {
-			conn, err = p2pconn.MakeSecretConnection(conn, sc.privKey.Wrap())
+		if rs.privKey != nil {
+			conn, err = p2pconn.MakeSecretConnection(conn, rs.privKey.Wrap())
 			if err != nil {
-				sc.Logger.Error(
+				rs.Logger.Error(
 					"sc connect",
 					"err", errors.Wrap(err, "encrypting connection failed"),
 				)
@@ -243,118 +430,16 @@ RETRY_LOOP:
 	return nil, ErrDialRetryMax
 }
 
-//---------------------------------------------------------
-
-// PrivValidatorSocketServer implements PrivValidator.
-// It responds to requests over a socket
-type PrivValidatorSocketServer struct {
-	cmn.BaseService
-
-	proto, addr    string
-	listener       net.Listener
-	maxConnections int
-	privKey        *crypto.PrivKeyEd25519
-
-	privVal PrivValidator
-	chainID string
-}
-
-// NewPrivValidatorSocketServer returns an instance of
-// PrivValidatorSocketServer.
-func NewPrivValidatorSocketServer(
-	logger log.Logger,
-	chainID, socketAddr string,
-	maxConnections int,
-	privVal PrivValidator,
-	privKey *crypto.PrivKeyEd25519,
-) *PrivValidatorSocketServer {
-	proto, addr := cmn.ProtocolAndAddress(socketAddr)
-	pvss := &PrivValidatorSocketServer{
-		proto:          proto,
-		addr:           addr,
-		maxConnections: maxConnections,
-		privKey:        privKey,
-		privVal:        privVal,
-		chainID:        chainID,
-	}
-	pvss.BaseService = *cmn.NewBaseService(logger, "privValidatorSocketServer", pvss)
-	return pvss
-}
-
-// OnStart implements cmn.Service.
-func (pvss *PrivValidatorSocketServer) OnStart() error {
-	ln, err := net.Listen(pvss.proto, pvss.addr)
-	if err != nil {
-		return err
-	}
-
-	pvss.listener = netutil.LimitListener(ln, pvss.maxConnections)
-
-	go pvss.acceptConnections()
-
-	return nil
-}
-
-// OnStop implements cmn.Service.
-func (pvss *PrivValidatorSocketServer) OnStop() {
-	if pvss.listener == nil {
-		return
-	}
-
-	if err := pvss.listener.Close(); err != nil {
-		pvss.Logger.Error("OnStop", "err", errors.Wrap(err, "closing listener failed"))
-	}
-}
-
-func (pvss *PrivValidatorSocketServer) acceptConnections() {
+func (rs *RemoteSigner) handleConnection(conn net.Conn) {
 	for {
-		conn, err := pvss.listener.Accept()
-		if err != nil {
-			if !pvss.IsRunning() {
-				return // Ignore error from listener closing.
-			}
-			pvss.Logger.Error(
-				"acceptConnections",
-				"err", errors.Wrap(err, "failed to accept connection"),
-			)
-			continue
-		}
-
-		if err := conn.SetDeadline(time.Now().Add(connDeadline)); err != nil {
-			pvss.Logger.Error(
-				"acceptConnetions",
-				"err", errors.Wrap(err, "setting connection timeout failed"),
-			)
-			continue
-		}
-
-		if pvss.privKey != nil {
-			conn, err = p2pconn.MakeSecretConnection(conn, pvss.privKey.Wrap())
-			if err != nil {
-				pvss.Logger.Error(
-					"acceptConnections",
-					"err", errors.Wrap(err, "secret connection failed"),
-				)
-				continue
-			}
-		}
-
-		go pvss.handleConnection(conn)
-	}
-}
-
-func (pvss *PrivValidatorSocketServer) handleConnection(conn net.Conn) {
-	defer conn.Close()
-
-	for {
-		if !pvss.IsRunning() {
+		if !rs.IsRunning() {
 			return // Ignore error from listener closing.
 		}
 
 		req, err := readMsg(conn)
 		if err != nil {
 			if err != io.EOF {
-				pvss.Logger.Error("handleConnection", "err", err)
+				rs.Logger.Error("handleConnection", "err", err)
 			}
 			return
 		}
@@ -365,29 +450,29 @@ func (pvss *PrivValidatorSocketServer) handleConnection(conn net.Conn) {
 		case *PubKeyMsg:
 			var p crypto.PubKey
 
-			p, err = pvss.privVal.PubKey()
+			p, err = rs.privVal.PubKey()
 			res = &PubKeyMsg{p}
 		case *SignVoteMsg:
-			err = pvss.privVal.SignVote(pvss.chainID, r.Vote)
+			err = rs.privVal.SignVote(rs.chainID, r.Vote)
 			res = &SignVoteMsg{r.Vote}
 		case *SignProposalMsg:
-			err = pvss.privVal.SignProposal(pvss.chainID, r.Proposal)
+			err = rs.privVal.SignProposal(rs.chainID, r.Proposal)
 			res = &SignProposalMsg{r.Proposal}
 		case *SignHeartbeatMsg:
-			err = pvss.privVal.SignHeartbeat(pvss.chainID, r.Heartbeat)
+			err = rs.privVal.SignHeartbeat(rs.chainID, r.Heartbeat)
 			res = &SignHeartbeatMsg{r.Heartbeat}
 		default:
 			err = fmt.Errorf("unknown msg: %v", r)
 		}
 
 		if err != nil {
-			pvss.Logger.Error("handleConnection", "err", err)
+			rs.Logger.Error("handleConnection", "err", err)
 			return
 		}
 
 		err = writeMsg(conn, res)
 		if err != nil {
-			pvss.Logger.Error("handleConnection", "err", err)
+			rs.Logger.Error("handleConnection", "err", err)
 			return
 		}
 	}
@@ -442,6 +527,10 @@ func readMsg(r io.Reader) (PrivValidatorSocketMsg, error) {
 
 	read := wire.ReadBinary(struct{ PrivValidatorSocketMsg }{}, r, 0, &n, &err)
 	if err != nil {
+		if opErr, ok := err.(*net.OpError); ok {
+			return nil, errors.Wrapf(ErrConnTimeout, opErr.Addr.String())
+		}
+
 		return nil, err
 	}
 
@@ -461,6 +550,9 @@ func writeMsg(w io.Writer, msg interface{}) error {
 
 	// TODO(xla): This extra wrap should be gone with the sdk-2 update.
 	wire.WriteBinary(struct{ PrivValidatorSocketMsg }{msg}, w, &n, &err)
+	if opErr, ok := err.(*net.OpError); ok {
+		return errors.Wrapf(ErrConnTimeout, opErr.Addr.String())
+	}
 
 	return err
 }

types/priv_validator/socket_test.go

@@ -4,10 +4,12 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pkg/errors"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 
 	crypto "github.com/tendermint/go-crypto"
+	cmn "github.com/tendermint/tmlibs/common"
 	"github.com/tendermint/tmlibs/log"
 
 	"github.com/tendermint/tendermint/types"
@@ -16,13 +18,13 @@ import (
 func TestSocketClientAddress(t *testing.T) {
 	var (
 		assert, require = assert.New(t), require.New(t)
-		chainID         = "test-chain-secret"
-		sc, pvss        = testSetupSocketPair(t, chainID)
+		chainID         = cmn.RandStr(12)
+		sc, rs          = testSetupSocketPair(t, chainID)
 	)
 	defer sc.Stop()
-	defer pvss.Stop()
+	defer rs.Stop()
 
-	serverAddr, err := pvss.privVal.Address()
+	serverAddr, err := rs.privVal.Address()
 	require.NoError(err)
 
 	clientAddr, err := sc.Address()
@@ -38,16 +40,16 @@ func TestSocketClientAddress(t *testing.T) {
 func TestSocketClientPubKey(t *testing.T) {
 	var (
 		assert, require = assert.New(t), require.New(t)
-		chainID         = "test-chain-secret"
-		sc, pvss        = testSetupSocketPair(t, chainID)
+		chainID         = cmn.RandStr(12)
+		sc, rs          = testSetupSocketPair(t, chainID)
 	)
 	defer sc.Stop()
-	defer pvss.Stop()
+	defer rs.Stop()
 
 	clientKey, err := sc.PubKey()
 	require.NoError(err)
 
-	privKey, err := pvss.privVal.PubKey()
+	privKey, err := rs.privVal.PubKey()
 	require.NoError(err)
 
 	assert.Equal(privKey, clientKey)
@@ -59,17 +61,17 @@ func TestSocketClientPubKey(t *testing.T) {
 func TestSocketClientProposal(t *testing.T) {
 	var (
 		assert, require = assert.New(t), require.New(t)
-		chainID         = "test-chain-secret"
-		sc, pvss        = testSetupSocketPair(t, chainID)
+		chainID         = cmn.RandStr(12)
+		sc, rs          = testSetupSocketPair(t, chainID)
 
 		ts             = time.Now()
 		privProposal   = &types.Proposal{Timestamp: ts}
 		clientProposal = &types.Proposal{Timestamp: ts}
 	)
 	defer sc.Stop()
-	defer pvss.Stop()
+	defer rs.Stop()
 
-	require.NoError(pvss.privVal.SignProposal(chainID, privProposal))
+	require.NoError(rs.privVal.SignProposal(chainID, privProposal))
 	require.NoError(sc.SignProposal(chainID, clientProposal))
 	assert.Equal(privProposal.Signature, clientProposal.Signature)
 }
@@ -77,8 +79,8 @@ func TestSocketClientProposal(t *testing.T) {
 func TestSocketClientVote(t *testing.T) {
 	var (
 		assert, require = assert.New(t), require.New(t)
-		chainID         = "test-chain-secret"
-		sc, pvss        = testSetupSocketPair(t, chainID)
+		chainID         = cmn.RandStr(12)
+		sc, rs          = testSetupSocketPair(t, chainID)
 
 		ts    = time.Now()
 		vType = types.VoteTypePrecommit
@@ -86,9 +88,9 @@ func TestSocketClientVote(t *testing.T) {
 		have  = &types.Vote{Timestamp: ts, Type: vType}
 	)
 	defer sc.Stop()
-	defer pvss.Stop()
+	defer rs.Stop()
 
-	require.NoError(pvss.privVal.SignVote(chainID, want))
+	require.NoError(rs.privVal.SignVote(chainID, want))
 	require.NoError(sc.SignVote(chainID, have))
 	assert.Equal(want.Signature, have.Signature)
 }
@@ -96,69 +98,129 @@ func TestSocketClientVote(t *testing.T) {
 func TestSocketClientHeartbeat(t *testing.T) {
 	var (
 		assert, require = assert.New(t), require.New(t)
-		chainID         = "test-chain-secret"
-		sc, pvss        = testSetupSocketPair(t, chainID)
+		chainID         = cmn.RandStr(12)
+		sc, rs          = testSetupSocketPair(t, chainID)
 
 		want = &types.Heartbeat{}
 		have = &types.Heartbeat{}
 	)
 	defer sc.Stop()
-	defer pvss.Stop()
+	defer rs.Stop()
 
-	require.NoError(pvss.privVal.SignHeartbeat(chainID, want))
+	require.NoError(rs.privVal.SignHeartbeat(chainID, want))
 	require.NoError(sc.SignHeartbeat(chainID, have))
 	assert.Equal(want.Signature, have.Signature)
 }
 
-func TestSocketClientConnectRetryMax(t *testing.T) {
+func TestSocketClientDeadline(t *testing.T) {
 	var (
-		assert, _     = assert.New(t), require.New(t)
-		logger        = log.TestingLogger()
-		clientPrivKey = crypto.GenPrivKeyEd25519()
-		sc            = NewSocketClient(
-			logger,
+		assert, require = assert.New(t), require.New(t)
+		readyc          = make(chan struct{})
+		sc              = NewSocketClient(
+			log.TestingLogger(),
 			"127.0.0.1:0",
-			&clientPrivKey,
+			nil,
 		)
 	)
 	defer sc.Stop()
 
-	SocketClientTimeout(time.Millisecond)(sc)
+	SocketClientConnDeadline(time.Millisecond)(sc)
 
-	assert.EqualError(sc.Start(), ErrDialRetryMax.Error())
+	require.NoError(sc.listen())
+
+	go func(sc *SocketClient) {
+		require.NoError(sc.Start())
+		assert.True(sc.IsRunning())
+
+		readyc <- struct{}{}
+	}(sc)
+
+	_, err := cmn.Connect(sc.listener.Addr().String())
+	require.NoError(err)
+
+	<-readyc
+
+	_, err = sc.PubKey()
+	assert.Equal(errors.Cause(err), ErrConnTimeout)
 }
 
-func testSetupSocketPair(t *testing.T, chainID string) (*SocketClient, *PrivValidatorSocketServer) {
+func TestSocketClientWait(t *testing.T) {
+	var (
+		assert, _ = assert.New(t), require.New(t)
+		logger    = log.TestingLogger()
+		privKey   = crypto.GenPrivKeyEd25519()
+		sc        = NewSocketClient(
+			logger,
+			"127.0.0.1:0",
+			&privKey,
+		)
+	)
+	defer sc.Stop()
+
+	SocketClientConnWait(time.Millisecond)(sc)
+
+	assert.EqualError(sc.Start(), ErrConnWaitTimeout.Error())
+}
+
+func TestRemoteSignerRetry(t *testing.T) {
+	var (
+		assert, _ = assert.New(t), require.New(t)
+		privKey   = crypto.GenPrivKeyEd25519()
+		rs        = NewRemoteSigner(
+			log.TestingLogger(),
+			cmn.RandStr(12),
+			"127.0.0.1:0",
+			NewTestPrivValidator(types.GenSigner()),
+			&privKey,
+		)
+	)
+	defer rs.Stop()
+
+	RemoteSignerConnDeadline(time.Millisecond)(rs)
+	RemoteSignerConnRetries(2)(rs)
+
+	assert.EqualError(rs.Start(), ErrDialRetryMax.Error())
+}
+
+func testSetupSocketPair(
+	t *testing.T,
+	chainID string,
+) (*SocketClient, *RemoteSigner) {
 	var (
 		assert, require = assert.New(t), require.New(t)
 		logger          = log.TestingLogger()
 		signer          = types.GenSigner()
 		clientPrivKey   = crypto.GenPrivKeyEd25519()
-		serverPrivKey   = crypto.GenPrivKeyEd25519()
+		remotePrivKey   = crypto.GenPrivKeyEd25519()
 		privVal         = NewTestPrivValidator(signer)
-		pvss            = NewPrivValidatorSocketServer(
+		readyc          = make(chan struct{})
+		sc              = NewSocketClient(
 			logger,
-			chainID,
 			"127.0.0.1:0",
-			1,
-			privVal,
-			&serverPrivKey,
+			&clientPrivKey,
 		)
 	)
 
-	err := pvss.Start()
-	require.NoError(err)
-	assert.True(pvss.IsRunning())
+	require.NoError(sc.listen())
 
-	sc := NewSocketClient(
+	go func(sc *SocketClient) {
+		require.NoError(sc.Start())
+		assert.True(sc.IsRunning())
+
+		readyc <- struct{}{}
+	}(sc)
+
+	rs := NewRemoteSigner(
 		logger,
-		pvss.listener.Addr().String(),
-		&clientPrivKey,
+		chainID,
+		sc.listener.Addr().String(),
+		privVal,
+		&remotePrivKey,
 	)
+	require.NoError(rs.Start())
+	assert.True(rs.IsRunning())
 
-	err = sc.Start()
-	require.NoError(err)
-	assert.True(sc.IsRunning())
+	<-readyc
 
-	return sc, pvss
+	return sc, rs
 }