syncthing/upnp/upnp.go
2014-07-22 22:47:54 +02:00

308 lines
7.2 KiB
Go

// Copyright (C) 2014 Jakob Borg and Contributors (see the CONTRIBUTORS file).
// All rights reserved. Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.
// Adapted from https://github.com/jackpal/Taipei-Torrent/blob/dd88a8bfac6431c01d959ce3c745e74b8a911793/IGD.go
// Copyright (c) 2010 Jack Palevich (https://github.com/jackpal/Taipei-Torrent/blob/dd88a8bfac6431c01d959ce3c745e74b8a911793/LICENSE)
// Package upnp implements UPnP Internet Gateway upnpDevice port mappings
package upnp
import (
"bufio"
"bytes"
"encoding/xml"
"errors"
"fmt"
"io"
"io/ioutil"
"net"
"net/http"
"net/url"
"strings"
"time"
)
type IGD struct {
serviceURL string
device string
ourIP string
}
type Protocol string
const (
TCP Protocol = "TCP"
UDP = "UDP"
)
type upnpService struct {
ServiceType string `xml:"serviceType"`
ControlURL string `xml:"controlURL"`
}
type upnpDevice struct {
DeviceType string `xml:"deviceType"`
Devices []upnpDevice `xml:"deviceList>device"`
Services []upnpService `xml:"serviceList>service"`
}
type upnpRoot struct {
Device upnpDevice `xml:"device"`
}
func Discover() (*IGD, error) {
ssdp := &net.UDPAddr{IP: []byte{239, 255, 255, 250}, Port: 1900}
socket, err := net.ListenUDP("udp4", &net.UDPAddr{})
if err != nil {
return nil, err
}
defer socket.Close()
err = socket.SetDeadline(time.Now().Add(3 * time.Second))
if err != nil {
return nil, err
}
searchStr := `M-SEARCH * HTTP/1.1
Host: 239.255.255.250:1900
St: urn:schemas-upnp-org:device:InternetGatewayDevice:1
Man: "ssdp:discover"
Mx: 3
`
search := []byte(strings.Replace(searchStr, "\n", "\r\n", -1))
_, err = socket.WriteTo(search, ssdp)
if err != nil {
return nil, err
}
resp := make([]byte, 1500)
n, _, err := socket.ReadFrom(resp)
if err != nil {
return nil, err
}
if debug {
l.Debugln(string(resp[:n]))
}
reader := bufio.NewReader(bytes.NewBuffer(resp[:n]))
request := &http.Request{}
response, err := http.ReadResponse(reader, request)
if err != nil {
return nil, err
}
if response.Header.Get("St") != "urn:schemas-upnp-org:device:InternetGatewayDevice:1" {
return nil, errors.New("no igd")
}
locURL := response.Header.Get("Location")
if locURL == "" {
return nil, errors.New("no location")
}
serviceURL, device, err := getServiceURL(locURL)
if err != nil {
return nil, err
}
// Figure out our IP number, on the network used to reach the IGD. We
// do this in a fairly roundabout way by connecting to the IGD and
// checking the address of the local end of the socket. I'm open to
// suggestions on a better way to do this...
ourIP, err := localIP(locURL)
if err != nil {
return nil, err
}
igd := &IGD{
serviceURL: serviceURL,
device: device,
ourIP: ourIP,
}
return igd, nil
}
func localIP(tgt string) (string, error) {
url, err := url.Parse(tgt)
if err != nil {
return "", err
}
conn, err := net.Dial("tcp", url.Host)
if err != nil {
return "", err
}
defer conn.Close()
ourIP, _, err := net.SplitHostPort(conn.LocalAddr().String())
if err != nil {
return "", err
}
return ourIP, nil
}
func getChildDevice(d upnpDevice, deviceType string) (upnpDevice, bool) {
for _, dev := range d.Devices {
if dev.DeviceType == deviceType {
return dev, true
}
}
return upnpDevice{}, false
}
func getChildService(d upnpDevice, serviceType string) (upnpService, bool) {
for _, svc := range d.Services {
if svc.ServiceType == serviceType {
return svc, true
}
}
return upnpService{}, false
}
func getServiceURL(rootURL string) (string, string, error) {
r, err := http.Get(rootURL)
if err != nil {
return "", "", err
}
defer r.Body.Close()
if r.StatusCode >= 400 {
return "", "", errors.New(r.Status)
}
return getServiceURLReader(rootURL, r.Body)
}
func getServiceURLReader(rootURL string, r io.Reader) (string, string, error) {
var upnpRoot upnpRoot
err := xml.NewDecoder(r).Decode(&upnpRoot)
if err != nil {
return "", "", err
}
dev := upnpRoot.Device
if dev.DeviceType != "urn:schemas-upnp-org:device:InternetGatewayDevice:1" {
return "", "", errors.New("No InternetGatewayDevice")
}
dev, ok := getChildDevice(dev, "urn:schemas-upnp-org:device:WANDevice:1")
if !ok {
return "", "", errors.New("No WANDevice")
}
dev, ok = getChildDevice(dev, "urn:schemas-upnp-org:device:WANConnectionDevice:1")
if !ok {
return "", "", errors.New("No WANConnectionDevice")
}
device := "urn:schemas-upnp-org:service:WANIPConnection:1"
svc, ok := getChildService(dev, device)
if !ok {
device = "urn:schemas-upnp-org:service:WANPPPConnection:1"
}
svc, ok = getChildService(dev, device)
if !ok {
return "", "", errors.New("No WANIPConnection nor WANPPPConnection")
}
if len(svc.ControlURL) == 0 {
return "", "", errors.New("no controlURL")
}
u, _ := url.Parse(rootURL)
replaceRawPath(u, svc.ControlURL)
return u.String(), device, nil
}
func replaceRawPath(u *url.URL, rp string) {
var p, q string
fs := strings.Split(rp, "?")
p = fs[0]
if len(fs) > 1 {
q = fs[1]
}
if p[0] == '/' {
u.Path = p
} else {
u.Path += p
}
u.RawQuery = q
}
func soapRequest(url, device, function, message string) error {
tpl := `<?xml version="1.0" ?>
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/">
<s:Body>%s</s:Body>
</s:Envelope>
`
body := fmt.Sprintf(tpl, message)
req, err := http.NewRequest("POST", url, strings.NewReader(body))
if err != nil {
return err
}
req.Header.Set("Content-Type", `text/xml; charset="utf-8"`)
req.Header.Set("User-Agent", "syncthing/1.0")
req.Header.Set("SOAPAction", fmt.Sprintf(`"%s#%s"`, device, function))
req.Header.Set("Connection", "Close")
req.Header.Set("Cache-Control", "no-cache")
req.Header.Set("Pragma", "no-cache")
if debug {
l.Debugln(req.Header.Get("SOAPAction"))
l.Debugln(body)
}
r, err := http.DefaultClient.Do(req)
if err != nil {
return err
}
if debug {
resp, _ := ioutil.ReadAll(r.Body)
l.Debugln(string(resp))
}
r.Body.Close()
if r.StatusCode >= 400 {
return errors.New(function + ": " + r.Status)
}
return nil
}
func (n *IGD) AddPortMapping(protocol Protocol, externalPort, internalPort int, description string, timeout int) error {
tpl := `<u:AddPortMapping xmlns:u="urn:schemas-upnp-org:service:WANIPConnection:1">
<NewRemoteHost></NewRemoteHost>
<NewExternalPort>%d</NewExternalPort>
<NewProtocol>%s</NewProtocol>
<NewInternalPort>%d</NewInternalPort>
<NewInternalClient>%s</NewInternalClient>
<NewEnabled>1</NewEnabled>
<NewPortMappingDescription>%s</NewPortMappingDescription>
<NewLeaseDuration>%d</NewLeaseDuration>
</u:AddPortMapping>
`
body := fmt.Sprintf(tpl, externalPort, protocol, internalPort, n.ourIP, description, timeout)
return soapRequest(n.serviceURL, n.device, "AddPortMapping", body)
}
func (n *IGD) DeletePortMapping(protocol Protocol, externalPort int) (err error) {
tpl := `<u:DeletePortMapping xmlns:u="urn:schemas-upnp-org:service:WANIPConnection:1">
<NewRemoteHost></NewRemoteHost>
<NewExternalPort>%d</NewExternalPort>
<NewProtocol>%s</NewProtocol>
</u:DeletePortMapping>
`
body := fmt.Sprintf(tpl, externalPort, protocol)
return soapRequest(n.serviceURL, n.device, "DeletePortMapping", body)
}