optimised finding server cert (#4148)

* optimised finding server cert

* make sure `close(done)` invoked only once

* remove sleep

* resolve IDE warning

* refactor for findServerCert

common/devices.go

@@ -1,5 +1,12 @@
 package common
 
+import "runtime"
+
 const (
 	AndroidPlatform = "android"
+	WindowsPlatform = "windows"
 )
+
+func OperatingSystemIs(targetOS string) bool {
+	return runtime.GOOS == targetOS
+}

protocol/common/shard.go

@@ -1,9 +1,10 @@
 package common
 
 import (
+	"github.com/waku-org/go-waku/waku/v2/protocol/relay"
+
 	"github.com/status-im/status-go/protocol/protobuf"
 	"github.com/status-im/status-go/protocol/transport"
-	"github.com/waku-org/go-waku/waku/v2/protocol/relay"
 )
 
 const MainStatusShardCluster = 16

server/ips.go

@@ -2,7 +2,6 @@ package server
 
 import (
 	"net"
-	"runtime"
 
 	"go.uber.org/zap"
 
@@ -98,7 +97,7 @@ func getAndroidLocalIP() ([][]net.IP, error) {
 func getLocalAddresses() ([][]net.IP, error) {
 	// TODO until we can resolve Android errors when calling net.Interfaces() just return the outbound local address.
 	//  Sorry Android
-	if runtime.GOOS == common.AndroidPlatform {
+	if common.OperatingSystemIs(common.AndroidPlatform) {
 		return getAndroidLocalIP()
 	}
 
@@ -192,7 +191,7 @@ func getAllAvailableNetworks() ([]net.IPNet, error) {
 // that returns a reachable server's address to be used by local pairing client.
 func FindReachableAddressesForPairingClient(serverIps []net.IP) ([]net.IP, error) {
 	// TODO until we can resolve Android errors when calling net.Interfaces() just noop. Sorry Android
-	if runtime.GOOS == common.AndroidPlatform {
+	if common.OperatingSystemIs(common.AndroidPlatform) {
 		return serverIps, nil
 	}
 

server/pairing/certs.go

@@ -114,7 +114,8 @@ func getServerCert(URL *url.URL) (*x509.Certificate, error) {
 		InsecureSkipVerify: true, // nolint: gosec // Only skip verify to get the server's TLS cert. DO NOT skip for any other reason.
 	}
 
-	conn, err := tls.Dial("tcp", URL.Host, conf)
+	// one second should be enough to get the server's TLS cert in LAN?
+	conn, err := tls.DialWithDialer(&net.Dialer{Timeout: time.Second}, "tcp", URL.Host, conf)
 	if err != nil {
 		return nil, err
 	}

server/pairing/client.go

@@ -8,10 +8,10 @@ import (
 	"encoding/pem"
 	"fmt"
 	"io"
+	"net"
 	"net/http"
 	"net/http/cookiejar"
 	"net/url"
-	"time"
 
 	"go.uber.org/zap"
 
@@ -38,31 +38,52 @@ type BaseClient struct {
 	challengeTaker *ChallengeTaker
 }
 
-func findServerCert(c *ConnectionParams) (*url.URL, *x509.Certificate, error) {
-	netIps, err := server.FindReachableAddressesForPairingClient(c.netIPs)
-	if err != nil {
-		return nil, nil, err
-	}
+func findServerCert(c *ConnectionParams, reachableIPs []net.IP) (*url.URL, *x509.Certificate, error) {
 	var baseAddress *url.URL
 	var serverCert *x509.Certificate
-	var certErrs error
-	for _, ip := range netIps {
+
+	type connectionError struct {
+		ip  net.IP
+		err error
+	}
+	errCh := make(chan connectionError, len(reachableIPs))
+
+	type result struct {
+		u    *url.URL
+		cert *x509.Certificate
+	}
+	successCh := make(chan result, 1) // as we close on the first success
+
+	for _, ip := range reachableIPs {
+		go func(ip net.IP) {
 			u := c.BuildURL(ip)
-
-		serverCert, err = getServerCert(u)
+			cert, err := getServerCert(u)
 			if err != nil {
-			var certErr string
-			if certErrs != nil {
-				certErr = certErrs.Error()
+				errCh <- connectionError{ip: ip, err: fmt.Errorf("connecting to '%s' failed: %s", u, err.Error())}
+				return
 			}
-			certErrs = fmt.Errorf("%sconnecting to '%s' failed: %s; ", certErr, u, err.Error())
-			continue
+			// If no error, send the results to the success channel
+			successCh <- result{u: u, cert: cert}
+		}(ip)
 	}
 
-		baseAddress = u
-		break
+	// Keep track of error counts
+	errorCount := 0
+	var combinedErrors string
+	for {
+		select {
+		case success := <-successCh:
+			baseAddress = success.u
+			serverCert = success.cert
+			return baseAddress, serverCert, nil
+		case ipErr := <-errCh:
+			errorCount++
+			combinedErrors += fmt.Sprintf("IP %s: %s; ", ipErr.ip, ipErr.err)
+			if errorCount == len(reachableIPs) {
+				return nil, nil, fmt.Errorf(combinedErrors)
+			}
+		}
 	}
-	return baseAddress, serverCert, certErrs
 }
 
 // NewBaseClient returns a fully qualified BaseClient from the given ConnectionParams
@@ -71,13 +92,19 @@ func NewBaseClient(c *ConnectionParams, logger *zap.Logger) (*BaseClient, error)
 	var serverCert *x509.Certificate
 	var certErrs error
 
+	netIPs, err := server.FindReachableAddressesForPairingClient(c.netIPs)
+	if err != nil {
+		logger.Error("[local pair client] failed to find reachable addresses", zap.Error(err), zap.Any("netIPs", netIPs))
+		signal.SendLocalPairingEvent(Event{Type: EventConnectionError, Error: err.Error(), Action: ActionConnect})
+		return nil, err
+	}
+
 	maxRetries := 3
 	for i := 0; i < maxRetries; i++ {
-		baseAddress, serverCert, certErrs = findServerCert(c)
+		baseAddress, serverCert, certErrs = findServerCert(c, netIPs)
 		if serverCert == nil {
 			certErrs = fmt.Errorf("failed to connect to any of given addresses. %w", certErrs)
-			time.Sleep(1 * time.Second)
-			logger.Warn("failed to connect to any of given addresses. Retrying...", zap.Error(certErrs))
+			logger.Warn("failed to connect to any of given addresses. Retrying...", zap.Error(certErrs), zap.Any("netIPs", netIPs), zap.Int("retry", i+1))
 		} else {
 			break
 		}
@@ -92,7 +119,7 @@ func NewBaseClient(c *ConnectionParams, logger *zap.Logger) (*BaseClient, error)
 	// No error on the dial out then the URL.Host is accessible
 	signal.SendLocalPairingEvent(Event{Type: EventConnectionSuccess, Action: ActionConnect})
 
-	err := verifyCert(serverCert, c.publicKey)
+	err = verifyCert(serverCert, c.publicKey)
 	if err != nil {
 		return nil, err
 	}

server/pairing/peers.go

@@ -45,7 +45,7 @@ func (p *PeerNotifier) handler(hello *peers.LocalPairingPeerHello) {
 
 func (p *PeerNotifier) Search() error {
 	// TODO until we can resolve Android errors when calling net.Interfaces() just noop. Sorry Android
-	if runtime.GOOS == common.AndroidPlatform {
+	if common.OperatingSystemIs(common.AndroidPlatform) {
 		return nil
 	}
 

t/utils/utils.go

@@ -12,12 +12,13 @@ import (
 	"os"
 	"path"
 	"path/filepath"
-	"runtime"
 	"strconv"
 	"strings"
 	"testing"
 	"time"
 
+	"github.com/status-im/status-go/common"
+
 	_ "github.com/stretchr/testify/suite" // required to register testify flags
 
 	"github.com/status-im/status-go/logutils"
@@ -222,7 +223,7 @@ func WaitClosed(c <-chan struct{}, d time.Duration) error {
 func MakeTestNodeConfig(networkID int) (*params.NodeConfig, error) {
 	testDir := filepath.Join(TestDataDir, TestNetworkNames[networkID])
 
-	if runtime.GOOS == "windows" {
+	if common.OperatingSystemIs(common.WindowsPlatform) {
 		testDir = filepath.ToSlash(testDir)
 	}