forked from miolini/upnp
/
SearchGatewayMsg.go
126 lines (112 loc) · 3.29 KB
/
SearchGatewayMsg.go
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package upnp
import (
"fmt"
"log"
"net"
"strings"
"time"
)
const (
readTimeout = 10 * time.Second
)
type Gateway struct {
GatewayName string //Gateway Name
Host string //Gateway ip and port
DeviceDescUrl string //Gateway device description path
Cache string //cache
ST string
USN string
deviceType string //Urn device "urn: schemas-upnp-org: service: WANIPConnection: 1"
ControlURL string //Device port mapping request path
ServiceType string //Upnp services provide the type of service
}
type SearchGateway struct {
searchMessage string
upnp *Upnp
}
func (this *SearchGateway) Send() (bool, error) {
this.buildRequest()
result, err := this.SendMessage()
if err != nil {
return false, err
}
if result == "" {
//Overtime
this.upnp.Active = false
return false, nil
}
this.resolve(result)
this.upnp.Gateway.ServiceType = "urn:schemas-upnp-org:service:WANIPConnection:1"
this.upnp.Active = true
return true, nil
}
func (this *SearchGateway) SendMessage() (result string, err error) {
//Send broadcast messages to bring the port, formats such as: "239.255.255.250:1900"
var conn *net.UDPConn
defer func() {
if r := recover(); r != nil {
err = fmt.Errorf("panic err: %s", r)
}
}()
remotAddr, err := net.ResolveUDPAddr("udp", "239.255.255.250:1900")
if err != nil {
return "", fmt.Errorf("Multicast address format is incorrect err: %s", err)
}
locaAddr, err := net.ResolveUDPAddr("udp", this.upnp.LocalHost+":0")
if err != nil {
return "", fmt.Errorf("Local IP address is incorrent err: %s", err)
}
conn, err = net.ListenUDP("udp", locaAddr)
if err != nil {
return "", fmt.Errorf("Listening udp error err: %s", err)
}
defer func(conn net.Conn) {
if err := conn.Close(); err != nil {
log.Printf("conn close err: %s", err)
}
}(conn)
_, err = conn.WriteToUDP([]byte(this.searchMessage), remotAddr)
if err != nil {
return "", fmt.Errorf("Sent to a multicast address err: %s", err)
}
buf := make([]byte, 1024)
err = conn.SetReadDeadline(time.Now().Add(readTimeout))
if err != nil {
return "", fmt.Errorf("Error setting deadline for connection: %s", err)
}
n, _, err := conn.ReadFromUDP(buf)
if err != nil {
return "", fmt.Errorf("Error message received from a multicast address: %s", err)
}
return string(buf[:n]), nil
}
func (this *SearchGateway) buildRequest() {
this.searchMessage = "M-SEARCH * HTTP/1.1\r\n" +
"HOST: 239.255.255.250:1900\r\n" +
"ST: urn:schemas-upnp-org:service:WANIPConnection:1\r\n" +
"MAN: \"ssdp:discover\"\r\n" + "MX: 3\r\n\r\n"
}
func (this *SearchGateway) resolve(result string) {
this.upnp.Gateway = &Gateway{}
lines := strings.Split(result, "\r\n")
for _, line := range lines {
//According to a first colon into two strings
nameValues := strings.SplitAfterN(line, ":", 2)
if len(nameValues) < 2 {
continue
}
switch strings.ToUpper(strings.Trim(strings.Split(nameValues[0], ":")[0], " ")) {
case "ST":
this.upnp.Gateway.ST = nameValues[1]
case "CACHE-CONTROL":
this.upnp.Gateway.Cache = nameValues[1]
case "LOCATION":
urls := strings.Split(strings.Split(nameValues[1], "//")[1], "/")
this.upnp.Gateway.Host = urls[0]
this.upnp.Gateway.DeviceDescUrl = "/" + urls[1]
case "SERVER":
this.upnp.Gateway.GatewayName = nameValues[1]
default:
}
}
}