From 3f503ffc7f85287fc3716afb704f90a1a4e7b21b Mon Sep 17 00:00:00 2001 From: obscuren Date: Sun, 2 Feb 2014 19:22:39 +0100 Subject: Implemented support for UPnP --- natupnp.go | 334 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 334 insertions(+) create mode 100644 natupnp.go (limited to 'natupnp.go') diff --git a/natupnp.go b/natupnp.go new file mode 100644 index 000000000..e4072d0dd --- /dev/null +++ b/natupnp.go @@ -0,0 +1,334 @@ +package eth + +// Just enough UPnP to be able to forward ports +// + +import ( + "bytes" + "encoding/xml" + "errors" + "net" + "net/http" + "os" + "strconv" + "strings" + "time" +) + +type upnpNAT struct { + serviceURL string + ourIP string +} + +func Discover() (nat NAT, err error) { + ssdp, err := net.ResolveUDPAddr("udp4", "239.255.255.250:1900") + if err != nil { + return + } + conn, err := net.ListenPacket("udp4", ":0") + if err != nil { + return + } + socket := conn.(*net.UDPConn) + defer socket.Close() + + err = socket.SetDeadline(time.Now().Add(10 * time.Second)) + if err != nil { + return + } + + st := "ST: urn:schemas-upnp-org:device:InternetGatewayDevice:1\r\n" + buf := bytes.NewBufferString( + "M-SEARCH * HTTP/1.1\r\n" + + "HOST: 239.255.255.250:1900\r\n" + + st + + "MAN: \"ssdp:discover\"\r\n" + + "MX: 2\r\n\r\n") + message := buf.Bytes() + answerBytes := make([]byte, 1024) + for i := 0; i < 3; i++ { + _, err = socket.WriteToUDP(message, ssdp) + if err != nil { + return + } + var n int + n, _, err = socket.ReadFromUDP(answerBytes) + if err != nil { + continue + // socket.Close() + // return + } + answer := string(answerBytes[0:n]) + if strings.Index(answer, "\r\n"+st) < 0 { + continue + } + // HTTP header field names are case-insensitive. + // http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2 + locString := "\r\nlocation: " + answer = strings.ToLower(answer) + locIndex := strings.Index(answer, locString) + if locIndex < 0 { + continue + } + loc := answer[locIndex+len(locString):] + endIndex := strings.Index(loc, "\r\n") + if endIndex < 0 { + continue + } + locURL := loc[0:endIndex] + var serviceURL string + serviceURL, err = getServiceURL(locURL) + if err != nil { + return + } + var ourIP string + ourIP, err = getOurIP() + if err != nil { + return + } + nat = &upnpNAT{serviceURL: serviceURL, ourIP: ourIP} + return + } + err = errors.New("UPnP port discovery failed.") + return +} + +// service represents the Service type in an UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type service struct { + ServiceType string `xml:"serviceType"` + ControlURL string `xml:"controlURL"` +} + +// deviceList represents the deviceList type in an UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type deviceList struct { + XMLName xml.Name `xml:"deviceList"` + Device []device `xml:"device"` +} + +// serviceList represents the serviceList type in an UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type serviceList struct { + XMLName xml.Name `xml:"serviceList"` + Service []service `xml:"service"` +} + +// device represents the device type in an UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type device struct { + XMLName xml.Name `xml:"device"` + DeviceType string `xml:"deviceType"` + DeviceList deviceList `xml:"deviceList"` + ServiceList serviceList `xml:"serviceList"` +} + +// specVersion represents the specVersion in a UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type specVersion struct { + XMLName xml.Name `xml:"specVersion"` + Major int `xml:"major"` + Minor int `xml:"minor"` +} + +// root represents the Root document for a UPnP xml description. +// Only the parts we care about are present and thus the xml may have more +// fields than present in the structure. +type root struct { + XMLName xml.Name `xml:"root"` + SpecVersion specVersion + Device device +} + +func getChildDevice(d *device, deviceType string) *device { + dl := d.DeviceList.Device + for i := 0; i < len(dl); i++ { + if dl[i].DeviceType == deviceType { + return &dl[i] + } + } + return nil +} + +func getChildService(d *device, serviceType string) *service { + sl := d.ServiceList.Service + for i := 0; i < len(sl); i++ { + if sl[i].ServiceType == serviceType { + return &sl[i] + } + } + return nil +} + +func getOurIP() (ip string, err error) { + hostname, err := os.Hostname() + if err != nil { + return + } + p, err := net.LookupIP(hostname) + if err != nil && len(p) > 0 { + return + } + return p[0].String(), nil +} + +func getServiceURL(rootURL string) (url string, err error) { + r, err := http.Get(rootURL) + if err != nil { + return + } + defer r.Body.Close() + if r.StatusCode >= 400 { + err = errors.New(string(r.StatusCode)) + return + } + var root root + err = xml.NewDecoder(r.Body).Decode(&root) + + if err != nil { + return + } + a := &root.Device + if a.DeviceType != "urn:schemas-upnp-org:device:InternetGatewayDevice:1" { + err = errors.New("No InternetGatewayDevice") + return + } + b := getChildDevice(a, "urn:schemas-upnp-org:device:WANDevice:1") + if b == nil { + err = errors.New("No WANDevice") + return + } + c := getChildDevice(b, "urn:schemas-upnp-org:device:WANConnectionDevice:1") + if c == nil { + err = errors.New("No WANConnectionDevice") + return + } + d := getChildService(c, "urn:schemas-upnp-org:service:WANIPConnection:1") + if d == nil { + err = errors.New("No WANIPConnection") + return + } + url = combineURL(rootURL, d.ControlURL) + return +} + +func combineURL(rootURL, subURL string) string { + protocolEnd := "://" + protoEndIndex := strings.Index(rootURL, protocolEnd) + a := rootURL[protoEndIndex+len(protocolEnd):] + rootIndex := strings.Index(a, "/") + return rootURL[0:protoEndIndex+len(protocolEnd)+rootIndex] + subURL +} + +func soapRequest(url, function, message string) (r *http.Response, err error) { + fullMessage := "" + + "\r\n" + + "" + message + "" + + req, err := http.NewRequest("POST", url, strings.NewReader(fullMessage)) + if err != nil { + return nil, err + } + req.Header.Set("Content-Type", "text/xml ; charset=\"utf-8\"") + req.Header.Set("User-Agent", "Darwin/10.0.0, UPnP/1.0, MiniUPnPc/1.3") + //req.Header.Set("Transfer-Encoding", "chunked") + req.Header.Set("SOAPAction", "\"urn:schemas-upnp-org:service:WANIPConnection:1#"+function+"\"") + req.Header.Set("Connection", "Close") + req.Header.Set("Cache-Control", "no-cache") + req.Header.Set("Pragma", "no-cache") + + // log.Stderr("soapRequest ", req) + //fmt.Println(fullMessage) + + r, err = http.DefaultClient.Do(req) + if r.Body != nil { + defer r.Body.Close() + } + + if r.StatusCode >= 400 { + // log.Stderr(function, r.StatusCode) + err = errors.New("Error " + strconv.Itoa(r.StatusCode) + " for " + function) + r = nil + return + } + return +} + +type statusInfo struct { + externalIpAddress string +} + +func (n *upnpNAT) getStatusInfo() (info statusInfo, err error) { + + message := "\r\n" + + "" + + var response *http.Response + response, err = soapRequest(n.serviceURL, "GetStatusInfo", message) + if err != nil { + return + } + + // TODO: Write a soap reply parser. It has to eat the Body and envelope tags... + + response.Body.Close() + return +} + +func (n *upnpNAT) GetExternalAddress() (addr net.IP, err error) { + info, err := n.getStatusInfo() + if err != nil { + return + } + addr = net.ParseIP(info.externalIpAddress) + return +} + +func (n *upnpNAT) AddPortMapping(protocol string, externalPort, internalPort int, description string, timeout int) (mappedExternalPort int, err error) { + // A single concatenation would break ARM compilation. + message := "\r\n" + + "" + strconv.Itoa(externalPort) + message += "" + protocol + "" + message += "" + strconv.Itoa(internalPort) + "" + + "" + n.ourIP + "" + + "1" + message += description + + "" + strconv.Itoa(timeout) + + "" + + var response *http.Response + response, err = soapRequest(n.serviceURL, "AddPortMapping", message) + if err != nil { + return + } + + // TODO: check response to see if the port was forwarded + // log.Println(message, response) + mappedExternalPort = externalPort + _ = response + return +} + +func (n *upnpNAT) DeletePortMapping(protocol string, externalPort, internalPort int) (err error) { + + message := "\r\n" + + "" + strconv.Itoa(externalPort) + + "" + protocol + "" + + "" + + var response *http.Response + response, err = soapRequest(n.serviceURL, "DeletePortMapping", message) + if err != nil { + return + } + + // TODO: check response to see if the port was deleted + // log.Println(message, response) + _ = response + return +} -- cgit v1.2.3