From d53b193e09e337d0ed4060275ed702baf3ff8d55 Mon Sep 17 00:00:00 2001
From: Jakob Borg <jakob@nym.se>
Date: Tue, 22 Apr 2014 11:46:08 +0200
Subject: [PATCH] Ensure sensible node config on load (fixes #143)

---
 cmd/syncthing/config.go      | 28 ++++++++++++++++----
 cmd/syncthing/config_test.go | 51 +++++++++++++++++++++++++++++++++---
 cmd/syncthing/main.go        |  5 ++--
 3 files changed, 72 insertions(+), 12 deletions(-)

diff --git a/cmd/syncthing/config.go b/cmd/syncthing/config.go
index 172040b5..8373adf6 100644
--- a/cmd/syncthing/config.go
+++ b/cmd/syncthing/config.go
@@ -3,6 +3,7 @@ package main
 import (
 	"encoding/xml"
 	"io"
+	"os"
 	"reflect"
 	"sort"
 	"strconv"
@@ -153,7 +154,7 @@ func uniqueStrings(ss []string) []string {
 	return us
 }
 
-func readConfigXML(rd io.Reader) (Configuration, error) {
+func readConfigXML(rd io.Reader, myID string) (Configuration, error) {
 	var cfg Configuration
 
 	setDefaults(&cfg)
@@ -169,6 +170,7 @@ func readConfigXML(rd io.Reader) (Configuration, error) {
 
 	cfg.Options.ListenAddress = uniqueStrings(cfg.Options.ListenAddress)
 
+	// Check for missing or duplicate repository ID:s
 	var seenRepos = map[string]bool{}
 	for i := range cfg.Repositories {
 		if cfg.Repositories[i].ID == "" {
@@ -182,10 +184,12 @@ func readConfigXML(rd io.Reader) (Configuration, error) {
 		seenRepos[id] = true
 	}
 
+	// Upgrade to v2 configuration if appropriate
 	if cfg.Version == 1 {
 		convertV1V2(&cfg)
 	}
 
+	// Hash old cleartext passwords
 	if len(cfg.GUI.Password) > 0 && cfg.GUI.Password[0] != '$' {
 		hash, err := bcrypt.GenerateFromPassword([]byte(cfg.GUI.Password), 0)
 		if err != nil {
@@ -195,6 +199,20 @@ func readConfigXML(rd io.Reader) (Configuration, error) {
 		}
 	}
 
+	// Ensure this node is present in all relevant places
+	cfg.Nodes = ensureNodePresent(cfg.Nodes, myID)
+	for i := range cfg.Repositories {
+		cfg.Repositories[i].Nodes = ensureNodePresent(cfg.Repositories[i].Nodes, myID)
+	}
+
+	// An empty address list is equivalent to a single "dynamic" entry
+	for i := range cfg.Nodes {
+		n := &cfg.Nodes[i]
+		if len(n.Addresses) == 0 || len(n.Addresses) == 1 && n.Addresses[0] == "" {
+			n.Addresses = []string{"dynamic"}
+		}
+	}
+
 	return cfg, err
 }
 
@@ -241,7 +259,7 @@ func (l NodeConfigurationList) Len() int {
 	return len(l)
 }
 
-func cleanNodeList(nodes []NodeConfiguration, myID string) []NodeConfiguration {
+func ensureNodePresent(nodes []NodeConfiguration, myID string) []NodeConfiguration {
 	var myIDExists bool
 	for _, node := range nodes {
 		if node.NodeID == myID {
@@ -251,10 +269,10 @@ func cleanNodeList(nodes []NodeConfiguration, myID string) []NodeConfiguration {
 	}
 
 	if !myIDExists {
+		name, _ := os.Hostname()
 		nodes = append(nodes, NodeConfiguration{
-			NodeID:    myID,
-			Addresses: []string{"dynamic"},
-			Name:      "",
+			NodeID: myID,
+			Name:   name,
 		})
 	}
 
diff --git a/cmd/syncthing/config_test.go b/cmd/syncthing/config_test.go
index 319e768f..04f3fa31 100644
--- a/cmd/syncthing/config_test.go
+++ b/cmd/syncthing/config_test.go
@@ -22,7 +22,7 @@ func TestDefaultValues(t *testing.T) {
 		UPnPEnabled:        true,
 	}
 
-	cfg, err := readConfigXML(bytes.NewReader(nil))
+	cfg, err := readConfigXML(bytes.NewReader(nil), "nodeID")
 	if err != io.EOF {
 		t.Error(err)
 	}
@@ -65,7 +65,7 @@ func TestNodeConfig(t *testing.T) {
 `)
 
 	for i, data := range [][]byte{v1data, v2data} {
-		cfg, err := readConfigXML(bytes.NewReader(data))
+		cfg, err := readConfigXML(bytes.NewReader(data), "node1")
 		if err != nil {
 			t.Error(err)
 		}
@@ -120,7 +120,7 @@ func TestNoListenAddress(t *testing.T) {
 </configuration>
 `)
 
-	cfg, err := readConfigXML(bytes.NewReader(data))
+	cfg, err := readConfigXML(bytes.NewReader(data), "nodeID")
 	if err != nil {
 		t.Error(err)
 	}
@@ -169,7 +169,7 @@ func TestOverriddenValues(t *testing.T) {
 		UPnPEnabled:        false,
 	}
 
-	cfg, err := readConfigXML(bytes.NewReader(data))
+	cfg, err := readConfigXML(bytes.NewReader(data), "nodeID")
 	if err != nil {
 		t.Error(err)
 	}
@@ -178,3 +178,46 @@ func TestOverriddenValues(t *testing.T) {
 		t.Errorf("Overridden config differs;\n  E: %#v\n  A: %#v", expected, cfg.Options)
 	}
 }
+
+func TestNodeAddresses(t *testing.T) {
+	data := []byte(`
+<configuration version="2">
+    <node id="n1">
+        <address>dynamic</address>
+    </node>
+    <node id="n2">
+        <address></address>
+    </node>
+    <node id="n3">
+    </node>
+</configuration>
+`)
+
+	expected := []NodeConfiguration{
+		{
+			NodeID:    "n1",
+			Addresses: []string{"dynamic"},
+		},
+		{
+			NodeID:    "n2",
+			Addresses: []string{"dynamic"},
+		},
+		{
+			NodeID:    "n3",
+			Addresses: []string{"dynamic"},
+		},
+		{
+			NodeID:    "n4",
+			Addresses: []string{"dynamic"},
+		},
+	}
+
+	cfg, err := readConfigXML(bytes.NewReader(data), "n4")
+	if err != nil {
+		t.Error(err)
+	}
+
+	if !reflect.DeepEqual(cfg.Nodes, expected) {
+		t.Errorf("Nodes differ;\n  E: %#v\n  A: %#v", expected, cfg.Nodes)
+	}
+}
diff --git a/cmd/syncthing/main.go b/cmd/syncthing/main.go
index ba0ffc76..71564a2c 100644
--- a/cmd/syncthing/main.go
+++ b/cmd/syncthing/main.go
@@ -137,7 +137,7 @@ func main() {
 	cf, err := os.Open(cfgFile)
 	if err == nil {
 		// Read config.xml
-		cfg, err = readConfigXML(cf)
+		cfg, err = readConfigXML(cf, myID)
 		if err != nil {
 			fatalln(err)
 		}
@@ -148,7 +148,7 @@ func main() {
 		infoln("No config file; starting with empty defaults")
 		name, _ := os.Hostname()
 
-		cfg, err = readConfigXML(nil)
+		cfg, err = readConfigXML(nil, myID)
 		cfg.Repositories = []RepositoryConfiguration{
 			{
 				ID:        "default",
@@ -206,7 +206,6 @@ func main() {
 	m := NewModel(cfg.Options.MaxChangeKbps * 1000)
 
 	for i := range cfg.Repositories {
-		cfg.Repositories[i].Nodes = cleanNodeList(cfg.Repositories[i].Nodes, myID)
 		dir := expandTilde(cfg.Repositories[i].Directory)
 		ensureDir(dir, -1)
 		m.AddRepo(cfg.Repositories[i].ID, dir, cfg.Repositories[i].Nodes)