syncthing/lib/config/config.go
2021-02-26 12:04:05 +01:00

606 lines
17 KiB
Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
// Package config implements reading and writing of the syncthing configuration file.
package config
import (
"encoding/json"
"encoding/xml"
"fmt"
"io"
"io/ioutil"
"net"
"net/url"
"os"
"runtime"
"sort"
"strconv"
"strings"
"github.com/pkg/errors"
"github.com/syncthing/syncthing/lib/fs"
"github.com/syncthing/syncthing/lib/protocol"
"github.com/syncthing/syncthing/lib/util"
)
const (
OldestHandledVersion = 10
CurrentVersion = 35
MaxRescanIntervalS = 365 * 24 * 60 * 60
)
var (
// DefaultTCPPort defines default TCP port used if the URI does not specify one, for example tcp://0.0.0.0
DefaultTCPPort = 22000
// DefaultQUICPort defines default QUIC port used if the URI does not specify one, for example quic://0.0.0.0
DefaultQUICPort = 22000
// DefaultListenAddresses should be substituted when the configuration
// contains <listenAddress>default</listenAddress>. This is done by the
// "consumer" of the configuration as we don't want these saved to the
// config.
DefaultListenAddresses = []string{
util.Address("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultTCPPort))),
"dynamic+https://relays.syncthing.net/endpoint",
util.Address("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(DefaultQUICPort))),
}
DefaultGUIPort = 8384
// DefaultDiscoveryServersV4 should be substituted when the configuration
// contains <globalAnnounceServer>default-v4</globalAnnounceServer>.
DefaultDiscoveryServersV4 = []string{
"https://discovery.syncthing.net/v2/?noannounce&id=LYXKCHX-VI3NYZR-ALCJBHF-WMZYSPK-QG6QJA3-MPFYMSO-U56GTUK-NA2MIAW",
"https://discovery-v4.syncthing.net/v2/?nolookup&id=LYXKCHX-VI3NYZR-ALCJBHF-WMZYSPK-QG6QJA3-MPFYMSO-U56GTUK-NA2MIAW",
}
// DefaultDiscoveryServersV6 should be substituted when the configuration
// contains <globalAnnounceServer>default-v6</globalAnnounceServer>.
DefaultDiscoveryServersV6 = []string{
"https://discovery.syncthing.net/v2/?noannounce&id=LYXKCHX-VI3NYZR-ALCJBHF-WMZYSPK-QG6QJA3-MPFYMSO-U56GTUK-NA2MIAW",
"https://discovery-v6.syncthing.net/v2/?nolookup&id=LYXKCHX-VI3NYZR-ALCJBHF-WMZYSPK-QG6QJA3-MPFYMSO-U56GTUK-NA2MIAW",
}
// DefaultDiscoveryServers should be substituted when the configuration
// contains <globalAnnounceServer>default</globalAnnounceServer>.
DefaultDiscoveryServers = append(DefaultDiscoveryServersV4, DefaultDiscoveryServersV6...)
// DefaultTheme is the default and fallback theme for the web UI.
DefaultTheme = "default"
// Default stun servers should be substituted when the configuration
// contains <stunServer>default</stunServer>.
// DefaultPrimaryStunServers are servers provided by us (to avoid causing the public servers burden)
DefaultPrimaryStunServers = []string{
"stun.syncthing.net:3478",
}
DefaultSecondaryStunServers = []string{
"stun.callwithus.com:3478",
"stun.counterpath.com:3478",
"stun.counterpath.net:3478",
"stun.ekiga.net:3478",
"stun.ideasip.com:3478",
"stun.internetcalls.com:3478",
"stun.schlund.de:3478",
"stun.sipgate.net:10000",
"stun.sipgate.net:3478",
"stun.voip.aebc.com:3478",
"stun.voiparound.com:3478",
"stun.voipbuster.com:3478",
"stun.voipstunt.com:3478",
"stun.xten.com:3478",
}
)
var (
errFolderIDEmpty = errors.New("folder has empty ID")
errFolderIDDuplicate = errors.New("folder has duplicate ID")
errFolderPathEmpty = errors.New("folder has empty path")
)
func New(myID protocol.DeviceID) Configuration {
var cfg Configuration
cfg.Version = CurrentVersion
cfg.Options.UnackedNotificationIDs = []string{"authenticationUserAndPassword"}
util.SetDefaults(&cfg)
// Can't happen.
if err := cfg.prepare(myID); err != nil {
l.Warnln("bug: error in preparing new folder:", err)
panic("error in preparing new folder")
}
return cfg
}
func NewWithFreePorts(myID protocol.DeviceID) (Configuration, error) {
cfg := New(myID)
port, err := getFreePort("127.0.0.1", DefaultGUIPort)
if err != nil {
return Configuration{}, errors.Wrap(err, "get free port (GUI)")
}
cfg.GUI.RawAddress = fmt.Sprintf("127.0.0.1:%d", port)
port, err = getFreePort("0.0.0.0", DefaultTCPPort)
if err != nil {
return Configuration{}, errors.Wrap(err, "get free port (BEP)")
}
if port == DefaultTCPPort {
cfg.Options.RawListenAddresses = []string{"default"}
} else {
cfg.Options.RawListenAddresses = []string{
util.Address("tcp", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
"dynamic+https://relays.syncthing.net/endpoint",
util.Address("quic", net.JoinHostPort("0.0.0.0", strconv.Itoa(port))),
}
}
return cfg, nil
}
type xmlConfiguration struct {
Configuration
XMLName xml.Name `xml:"configuration"`
}
func ReadXML(r io.Reader, myID protocol.DeviceID) (Configuration, int, error) {
var cfg xmlConfiguration
util.SetDefaults(&cfg)
if err := xml.NewDecoder(r).Decode(&cfg); err != nil {
return Configuration{}, 0, err
}
originalVersion := cfg.Version
if err := cfg.prepare(myID); err != nil {
return Configuration{}, originalVersion, err
}
return cfg.Configuration, originalVersion, nil
}
func ReadJSON(r io.Reader, myID protocol.DeviceID) (Configuration, error) {
var cfg Configuration
util.SetDefaults(&cfg)
bs, err := ioutil.ReadAll(r)
if err != nil {
return Configuration{}, err
}
if err := json.Unmarshal(bs, &cfg); err != nil {
return Configuration{}, err
}
if err := cfg.prepare(myID); err != nil {
return Configuration{}, err
}
return cfg, nil
}
func (cfg Configuration) Copy() Configuration {
newCfg := cfg
// Deep copy FolderConfigurations
newCfg.Folders = make([]FolderConfiguration, len(cfg.Folders))
for i := range newCfg.Folders {
newCfg.Folders[i] = cfg.Folders[i].Copy()
}
// Deep copy DeviceConfigurations
newCfg.Devices = make([]DeviceConfiguration, len(cfg.Devices))
for i := range newCfg.Devices {
newCfg.Devices[i] = cfg.Devices[i].Copy()
}
newCfg.Options = cfg.Options.Copy()
newCfg.GUI = cfg.GUI.Copy()
// DeviceIDs are values
newCfg.IgnoredDevices = make([]ObservedDevice, len(cfg.IgnoredDevices))
copy(newCfg.IgnoredDevices, cfg.IgnoredDevices)
return newCfg
}
func (cfg *Configuration) WriteXML(w io.Writer) error {
e := xml.NewEncoder(w)
e.Indent("", " ")
xmlCfg := xmlConfiguration{Configuration: *cfg}
err := e.Encode(xmlCfg)
if err != nil {
return err
}
_, err = w.Write([]byte("\n"))
return err
}
func (cfg *Configuration) prepare(myID protocol.DeviceID) error {
cfg.ensureMyDevice(myID)
existingDevices, err := cfg.prepareFoldersAndDevices(myID)
if err != nil {
return err
}
cfg.GUI.prepare()
guiPWIsSet := cfg.GUI.User != "" && cfg.GUI.Password != ""
cfg.Options.prepare(guiPWIsSet)
cfg.prepareIgnoredDevices(existingDevices)
cfg.Defaults.prepare(myID, existingDevices)
cfg.removeDeprecatedProtocols()
util.FillNilExceptDeprecated(cfg)
// TestIssue1750 relies on migrations happening after preparing options.
cfg.applyMigrations()
return nil
}
func (cfg *Configuration) ensureMyDevice(myID protocol.DeviceID) {
for _, device := range cfg.Devices {
if device.DeviceID == myID {
return
}
}
myName, _ := os.Hostname()
cfg.Devices = append(cfg.Devices, DeviceConfiguration{
DeviceID: myID,
Name: myName,
})
}
func (cfg *Configuration) prepareFoldersAndDevices(myID protocol.DeviceID) (map[protocol.DeviceID]bool, error) {
existingDevices := cfg.prepareDeviceList()
sharedFolders, err := cfg.prepareFolders(myID, existingDevices)
if err != nil {
return nil, err
}
cfg.prepareDevices(sharedFolders)
return existingDevices, nil
}
func (cfg *Configuration) prepareDeviceList() map[protocol.DeviceID]bool {
// Ensure that the device list is
// - free from duplicates
// - no devices with empty ID
// - sorted by ID
// Happen before preparting folders as that needs a correct device list.
cfg.Devices = ensureNoDuplicateOrEmptyIDDevices(cfg.Devices)
sort.Slice(cfg.Devices, func(a, b int) bool {
return cfg.Devices[a].DeviceID.Compare(cfg.Devices[b].DeviceID) == -1
})
// Build a list of available devices
existingDevices := make(map[protocol.DeviceID]bool, len(cfg.Devices))
for _, device := range cfg.Devices {
existingDevices[device.DeviceID] = true
}
return existingDevices
}
func (cfg *Configuration) prepareFolders(myID protocol.DeviceID, existingDevices map[protocol.DeviceID]bool) (map[protocol.DeviceID][]string, error) {
// Prepare folders and check for duplicates. Duplicates are bad and
// dangerous, can't currently be resolved in the GUI, and shouldn't
// happen when configured by the GUI. We return with an error in that
// situation.
sharedFolders := make(map[protocol.DeviceID][]string, len(cfg.Devices))
existingFolders := make(map[string]*FolderConfiguration, len(cfg.Folders))
for i := range cfg.Folders {
folder := &cfg.Folders[i]
if folder.ID == "" {
return nil, errFolderIDEmpty
}
if folder.Path == "" {
return nil, fmt.Errorf("folder %q: %w", folder.ID, errFolderPathEmpty)
}
if _, ok := existingFolders[folder.ID]; ok {
return nil, fmt.Errorf("folder %q: %w", folder.ID, errFolderIDDuplicate)
}
folder.prepare(myID, existingDevices)
existingFolders[folder.ID] = folder
for _, dev := range folder.Devices {
sharedFolders[dev.DeviceID] = append(sharedFolders[dev.DeviceID], folder.ID)
}
}
// Ensure that the folder list is sorted by ID
sort.Slice(cfg.Folders, func(a, b int) bool {
return cfg.Folders[a].ID < cfg.Folders[b].ID
})
return sharedFolders, nil
}
func (cfg *Configuration) prepareDevices(sharedFolders map[protocol.DeviceID][]string) {
for i := range cfg.Devices {
cfg.Devices[i].prepare(sharedFolders[cfg.Devices[i].DeviceID])
}
}
func (cfg *Configuration) prepareIgnoredDevices(existingDevices map[protocol.DeviceID]bool) map[protocol.DeviceID]bool {
// The list of ignored devices should not contain any devices that have
// been manually added to the config.
newIgnoredDevices := cfg.IgnoredDevices[:0]
ignoredDevices := make(map[protocol.DeviceID]bool, len(cfg.IgnoredDevices))
for _, dev := range cfg.IgnoredDevices {
if !existingDevices[dev.ID] {
ignoredDevices[dev.ID] = true
newIgnoredDevices = append(newIgnoredDevices, dev)
}
}
cfg.IgnoredDevices = newIgnoredDevices
return ignoredDevices
}
func (cfg *Configuration) removeDeprecatedProtocols() {
// Deprecated protocols are removed from the list of listeners and
// device addresses. So far just kcp*.
for _, prefix := range []string{"kcp"} {
cfg.Options.RawListenAddresses = filterURLSchemePrefix(cfg.Options.RawListenAddresses, prefix)
for i := range cfg.Devices {
dev := &cfg.Devices[i]
dev.Addresses = filterURLSchemePrefix(dev.Addresses, prefix)
}
}
}
func (cfg *Configuration) applyMigrations() {
if cfg.Version > 0 && cfg.Version < OldestHandledVersion {
l.Warnf("Configuration version %d is deprecated. Attempting best effort conversion, but please verify manually.", cfg.Version)
}
// Upgrade configuration versions as appropriate
migrationsMut.Lock()
migrations.apply(cfg)
migrationsMut.Unlock()
}
func (cfg *Configuration) Device(id protocol.DeviceID) (DeviceConfiguration, int, bool) {
for i, device := range cfg.Devices {
if device.DeviceID == id {
return device, i, true
}
}
return DeviceConfiguration{}, 0, false
}
// DeviceMap returns a map of device ID to device configuration for the given configuration.
func (cfg *Configuration) DeviceMap() map[protocol.DeviceID]DeviceConfiguration {
m := make(map[protocol.DeviceID]DeviceConfiguration, len(cfg.Devices))
for _, dev := range cfg.Devices {
m[dev.DeviceID] = dev
}
return m
}
func (cfg *Configuration) SetDevice(device DeviceConfiguration) {
cfg.SetDevices([]DeviceConfiguration{device})
}
func (cfg *Configuration) SetDevices(devices []DeviceConfiguration) {
inds := make(map[protocol.DeviceID]int, len(cfg.Devices))
for i, device := range cfg.Devices {
inds[device.DeviceID] = i
}
filtered := devices[:0]
for _, device := range devices {
if i, ok := inds[device.DeviceID]; ok {
cfg.Devices[i] = device
} else {
filtered = append(filtered, device)
}
}
cfg.Devices = append(cfg.Devices, filtered...)
}
func (cfg *Configuration) Folder(id string) (FolderConfiguration, int, bool) {
for i, folder := range cfg.Folders {
if folder.ID == id {
return folder, i, true
}
}
return FolderConfiguration{}, 0, false
}
// FolderMap returns a map of folder ID to folder configuration for the given configuration.
func (cfg *Configuration) FolderMap() map[string]FolderConfiguration {
m := make(map[string]FolderConfiguration, len(cfg.Folders))
for _, folder := range cfg.Folders {
m[folder.ID] = folder
}
return m
}
// FolderPasswords returns the folder passwords set for this device, for
// folders that have an encryption password set.
func (cfg Configuration) FolderPasswords(device protocol.DeviceID) map[string]string {
res := make(map[string]string, len(cfg.Folders))
nextFolder:
for _, folder := range cfg.Folders {
for _, dev := range folder.Devices {
if dev.DeviceID == device && dev.EncryptionPassword != "" {
res[folder.ID] = dev.EncryptionPassword
continue nextFolder
}
}
}
return res
}
func (cfg *Configuration) SetFolder(folder FolderConfiguration) {
cfg.SetFolders([]FolderConfiguration{folder})
}
func (cfg *Configuration) SetFolders(folders []FolderConfiguration) {
inds := make(map[string]int, len(cfg.Folders))
for i, folder := range cfg.Folders {
inds[folder.ID] = i
}
filtered := folders[:0]
for _, folder := range folders {
if i, ok := inds[folder.ID]; ok {
cfg.Folders[i] = folder
} else {
filtered = append(filtered, folder)
}
}
cfg.Folders = append(cfg.Folders, filtered...)
}
func ensureDevicePresent(devices []FolderDeviceConfiguration, myID protocol.DeviceID) []FolderDeviceConfiguration {
for _, device := range devices {
if device.DeviceID.Equals(myID) {
return devices
}
}
devices = append(devices, FolderDeviceConfiguration{
DeviceID: myID,
})
return devices
}
func ensureExistingDevices(devices []FolderDeviceConfiguration, existingDevices map[protocol.DeviceID]bool) []FolderDeviceConfiguration {
count := len(devices)
i := 0
loop:
for i < count {
if _, ok := existingDevices[devices[i].DeviceID]; !ok {
devices[i] = devices[count-1]
count--
continue loop
}
i++
}
return devices[0:count]
}
func ensureNoDuplicateFolderDevices(devices []FolderDeviceConfiguration) []FolderDeviceConfiguration {
count := len(devices)
i := 0
seenDevices := make(map[protocol.DeviceID]bool)
loop:
for i < count {
id := devices[i].DeviceID
if _, ok := seenDevices[id]; ok {
devices[i] = devices[count-1]
count--
continue loop
}
seenDevices[id] = true
i++
}
return devices[0:count]
}
func ensureNoDuplicateOrEmptyIDDevices(devices []DeviceConfiguration) []DeviceConfiguration {
count := len(devices)
i := 0
seenDevices := make(map[protocol.DeviceID]bool)
loop:
for i < count {
id := devices[i].DeviceID
if _, ok := seenDevices[id]; ok || id == protocol.EmptyDeviceID {
devices[i] = devices[count-1]
count--
continue loop
}
seenDevices[id] = true
i++
}
return devices[0:count]
}
func cleanSymlinks(filesystem fs.Filesystem, dir string) {
if runtime.GOOS == "windows" {
// We don't do symlinks on Windows. Additionally, there may
// be things that look like symlinks that are not, which we
// should leave alone. Deduplicated files, for example.
return
}
filesystem.Walk(dir, func(path string, info fs.FileInfo, err error) error {
if err != nil {
return err
}
if info.IsSymlink() {
l.Infoln("Removing incorrectly versioned symlink", path)
filesystem.Remove(path)
return fs.SkipDir
}
return nil
})
}
// filterURLSchemePrefix returns the list of addresses after removing all
// entries whose URL scheme matches the given prefix.
func filterURLSchemePrefix(addrs []string, prefix string) []string {
for i := 0; i < len(addrs); i++ {
uri, err := url.Parse(addrs[i])
if err != nil {
continue
}
if strings.HasPrefix(uri.Scheme, prefix) {
// Remove this entry
copy(addrs[i:], addrs[i+1:])
addrs = addrs[:len(addrs)-1]
i--
}
}
return addrs
}
// tried in succession and the first to succeed is returned. If none succeed,
// a random high port is returned.
func getFreePort(host string, ports ...int) (int, error) {
for _, port := range ports {
c, err := net.Listen("tcp", fmt.Sprintf("%s:%d", host, port))
if err == nil {
c.Close()
return port, nil
}
}
c, err := net.Listen("tcp", host+":0")
if err != nil {
return 0, err
}
addr := c.Addr().(*net.TCPAddr)
c.Close()
return addr.Port, nil
}
func (defaults *Defaults) prepare(myID protocol.DeviceID, existingDevices map[protocol.DeviceID]bool) {
ensureZeroForNodefault(&FolderConfiguration{}, &defaults.Folder)
ensureZeroForNodefault(&DeviceConfiguration{}, &defaults.Device)
defaults.Folder.prepare(myID, existingDevices)
defaults.Device.prepare(nil)
}
func ensureZeroForNodefault(empty interface{}, target interface{}) {
util.CopyMatchingTag(empty, target, "nodefault", func(v string) bool {
if len(v) > 0 && v != "true" {
panic(fmt.Sprintf(`unexpected tag value: %s. expected untagged or "true"`, v))
}
return len(v) > 0
})
}