Refactor node ID handling, use check digits (fixes #269)

New node ID:s contain four Luhn check digits and are grouped
differently. Code uses NodeID type instead of string, so it's formatted
homogenously everywhere.

cmd/syncthing/gui.go

@@ -327,7 +327,7 @@ func restGetSystem(w http.ResponseWriter) {
 	runtime.ReadMemStats(&m)
 
 	res := make(map[string]interface{})
-	res["myID"] = myID
+	res["myID"] = myID.String()
 	res["goroutines"] = runtime.NumGoroutine()
 	res["alloc"] = m.Alloc
 	res["sys"] = m.Sys

cmd/syncthing/main.go

@@ -61,7 +61,7 @@ func init() {
 
 var (
 	cfg        config.Configuration
-	myID       string
+	myID       protocol.NodeID
 	confDir    string
 	logFlags   int = log.Ltime
 	rateBucket *ratelimit.Bucket
@@ -181,8 +181,8 @@ func main() {
 		l.FatalErr(err)
 	}
 
-	myID = certID(cert.Certificate[0])
-	l.SetPrefix(fmt.Sprintf("[%s] ", myID[:5]))
+	myID = protocol.NewNodeID(cert.Certificate[0])
+	l.SetPrefix(fmt.Sprintf("[%s] ", myID.String()[:5]))
 
 	l.Infoln(LongVersion)
 	l.Infoln("My ID:", myID)
@@ -263,7 +263,7 @@ func main() {
 	tlsCfg := &tls.Config{
 		Certificates:           []tls.Certificate{cert},
 		NextProtos:             []string{"bep/1.0"},
-		ServerName:             myID,
+		ServerName:             myID.String(),
 		ClientAuth:             tls.RequestClientCert,
 		SessionTicketsDisabled: true,
 		InsecureSkipVerify:     true,
@@ -567,7 +567,7 @@ func saveConfig() {
 	saveConfigCh <- struct{}{}
 }
 
-func listenConnect(myID string, m *model.Model, tlsCfg *tls.Config) {
+func listenConnect(myID protocol.NodeID, m *model.Model, tlsCfg *tls.Config) {
 	var conns = make(chan *tls.Conn)
 
 	// Listen
@@ -673,7 +673,7 @@ next:
 			conn.Close()
 			continue
 		}
-		remoteID := certID(certs[0].Raw)
+		remoteID := protocol.NewNodeID(certs[0].Raw)
 
 		if remoteID == myID {
 			l.Infof("Connected to myself (%s) - should not happen", remoteID)

cmd/syncthing/tls.go

@@ -11,14 +11,12 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"crypto/x509/pkix"
-	"encoding/base32"
 	"encoding/binary"
 	"encoding/pem"
 	"math/big"
 	mr "math/rand"
 	"os"
 	"path/filepath"
-	"strings"
 	"time"
 )
 
@@ -28,14 +26,9 @@ const (
 )
 
 func loadCert(dir string, prefix string) (tls.Certificate, error) {
-	return tls.LoadX509KeyPair(filepath.Join(dir, prefix+"cert.pem"), filepath.Join(dir, prefix+"key.pem"))
-}
-
-func certID(bs []byte) string {
-	hf := sha256.New()
-	hf.Write(bs)
-	id := hf.Sum(nil)
-	return strings.Trim(base32.StdEncoding.EncodeToString(id), "=")
+	cf := filepath.Join(dir, prefix+"cert.pem")
+	kf := filepath.Join(dir, prefix+"key.pem")
+	return tls.LoadX509KeyPair(cf, kf)
 }
 
 func certSeed(bs []byte) int64 {

cmd/syncthing/usage_report.go

@@ -23,7 +23,7 @@ var stopUsageReportingCh = make(chan struct{})
 
 func reportData(m *model.Model) map[string]interface{} {
 	res := make(map[string]interface{})
-	res["uniqueID"] = strings.ToLower(certID([]byte(myID)))[:6]
+	res["uniqueID"] = strings.ToLower(myID.String()[:6])
 	res["version"] = Version
 	res["longVersion"] = LongVersion
 	res["platform"] = runtime.GOOS + "-" + runtime.GOARCH