Service requests against Fritz!Box devices fail

[wichert]

I am trying a very simple test against a Fritz!Box device:

package main

import (
    "fmt"
    "log"
    "github.com/huin/goupnp/dcps/internetgateway1"
)


func main() {
    clients, _, err := internetgateway1.NewWANIPConnection1Clients ()
    if err != nil {
        log.Fatal(err)
    }
    for _, client := range clients {
        status, _, _, err := client.GetStatusInfo()
        if err != nil {
            log.Fatal(err)
        }
        fmt.Println(status)
    }
}

but this always fails:

2014/06/05 11:30:25 goupnp: SOAP request got HTTP 500 Internal Server Error

[wichert]

I did a bit of on-wire sniffing to compare what goupnp does versus what miniupnpc does. This is a working request from miniupunc:

POST /igdupnp/control/WANIPConn1 HTTP/1.1
Host: 192.168.178.1:49000
User-Agent: Darwin/13.0.0, UPnP/1.0, MiniUPnPc/1.9
Content-Length: 271
Content-Type: text/xml
SOAPAction: "urn:schemas-upnp-org:service:WANIPConnection:1#GetStatusInfo"
Connection: Close
Cache-Control: no-cache
Pragma: no-cache

<?xml version="1.0"?>
<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"><s:Body><u:GetStatusInfo xmlns:u="urn:schemas-upnp-org:service:WANIPConnection:1"></u:GetStatusInfo></s:Body></s:Envelope>

This is a failing request from goupnp:

POST /igdupnp/control/WANIPConn1 HTTP/1.1
Host: 192.168.178.1:49000
User-Agent: Go 1.1 package http
Content-Length: 154
CONTENT-TYPE: text/xml; charset="utf-8"
SOAPACTION: urn:schemas-upnp-org:service:WANIPConnection:1#GetStatusInfo
Accept-Encoding: gzip

<s:Envelope xmlns:s="http://schemas.xmlsoap.org/soap/envelope/" s:encodingStyle="http://schemas.xmlsoap.org/soap/encoding/"><s:Body></s:Body></s:Envelope>

This shows several differences:

1. miniupunc includes the <?xml version="1.0" encoding="utf-8"?> preamble.
2. miniupunc includes an <u:GetStatusInfo xmlns:u="urn:schemas-upnp-org:service:WANIPConnection:1"> element in the SOAP body.

I suspect the latter part is the critical one.

[wichert]

I did a very quick hack by modifying encodeRequestAction:

func encodeRequestAction(inAction interface{}) ([]byte, error) {
    requestBuf := new(bytes.Buffer)
    requestBuf.WriteString(soapPrefix)
    requestBuf.WriteString("<u:GetStatusInfo xmlns:u=\"urn:schemas-upnp-org:service:WANIPConnection:1\"></u:GetStatusInfo>")

That indeed fixed the 500 errors.

[huin]

You're quite right... I suspect this never worked, and I never tested things that actually required arguments to the action (ugh, lazy me - that's pretty bad). Thanks for reporting this.

I've pushed a fix. It's not pretty... but then, Go's support for controlling namespace prefixes is a pain, and a lot of UPnP servers seem to choke on most of the XML that Go's XML library emits (even though it's valid).

Let me know if that works for you!

[huin]

I realised shortly after writing a reply that while this code works for actions with no parameters, I'm not sure that I ever got around to testing actions with parameters. I'll need to do that... Probably setting up some basic unit tests around soap actions.

[huin]

I've added a test and confirmed a fix as working with parameters as well now. This should now be in a better state.

[wichert]

Thanks, this works correctly for me now.

[huin]

Excellent, thanks for the confirmation.