.NET based SOAP proxy and HTTP Basic Authentication

[Tony Stephens]

Hi,

I've created a small forms based application in c# to test a vendor's
product and the web service interface that it exposes. We have deployed two
instances of the vendor product one which has an unprotected (no
authentication) interface and one that is protected using HTTP basic
authentication.

I can invoke methods on the unprotected instance and everything's fine. When
I attempt to invoke methods on the protected instance the request sent in
response to the challenge from the server is truncated and has no message
body.

Ethereal trace below:

POST /ProvisionInterf ace HTTP/1.1
VsDebuggerCausa lityData: <data snipped>
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; MS Web Services Client
Protocol 1.1.4322.2032)
Content-Type: text/xml; charset=utf-8
SOAPAction: "http://www.blug.com/wsdlUserExists"
Content-Length: 387
Expect: 100-continue
Connection: Keep-Alive
Host: 1.2.3.4:50000

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelop e xmlns:soap="htt p://schemas.xmlsoap .org/soap/envelope/"
xmlns:xsi="http ://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http ://www.w3.org/2001/XMLSchema">
<soap:Body>
<UserExists xmlns="http://www.blug.com/wsdl">
<PublicID>
<id>te***@bt.co .uk</id>
<type>1</type>
</PublicID>
</UserExists>
</soap:Body>
</soap:Envelope>

HTTP/1.1 401 UNAUTHORIZED
WWW-Authenticate: Basic realm="Provisio nInterface"
cache-control: no-cache
content-length: 25
content-type: text/html
date: Thu, 22 Jun 2006 12:35:34 GMT
last-modified: Thu, 22 Jun 2006 12:35:34 GMT

POST /ProvisionInterf ace HTTP/1.1
VsDebuggerCausa lityData: <data snipped>
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; MS Web Services Client
Protocol 1.1.4322.2032)
Content-Type: text/xml; charset=utf-8
SOAPAction: "http://www.blug.com/wsdlUserExists"
Authorization: Basic UFdTSToxMjM0
Content-Length: 387
Expect: 100-continue
Host: 1.2.3.4:50000

<*** message body missing/truncated ***>

The only means I know of influencing the authentication phase is by
attaching a NetworkCredenti al object to the SOAP proxy and the authentication
process is transparent to the application as far as I'm aware.

Has anyone else experienced this problem ?

Thanks,

Tony

[Tony Stephens]

I've figured out what the problem was (for anyone else who's interested).

It appears that the vendor product is not responding to the
Expect:100-Continue header correctly (i.e. returning 417 Expectation Failed
to indicate it's not a supported feature) and so the SOAP proxy is waiting
for a 100 Continue provisional response prior to sending the message body.

The following line of code stops the SOAP proxy from adding this header to
the SOAP request:

System.Net.Serv icePointManager .Expect100Conti nue = false;
Regards,

Tony

"Tony Stephens" wrote:

Hi,

I've created a small forms based application in c# to test a vendor's
product and the web service interface that it exposes. We have deployed two
instances of the vendor product one which has an unprotected (no
authentication) interface and one that is protected using HTTP basic
authentication.

I can invoke methods on the unprotected instance and everything's fine. When
I attempt to invoke methods on the protected instance the request sent in
response to the challenge from the server is truncated and has no message
body.

Ethereal trace below:

POST /ProvisionInterf ace HTTP/1.1
VsDebuggerCausa lityData: <data snipped>
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; MS Web Services Client
Protocol 1.1.4322.2032)
Content-Type: text/xml; charset=utf-8
SOAPAction: "http://www.blug.com/wsdlUserExists"
Content-Length: 387
Expect: 100-continue
Connection: Keep-Alive
Host: 1.2.3.4:50000

<?xml version="1.0" encoding="utf-8"?>
<soap:Envelop e xmlns:soap="htt p://schemas.xmlsoap .org/soap/envelope/"
xmlns:xsi="http ://www.w3.org/2001/XMLSchema-instance"
xmlns:xsd="http ://www.w3.org/2001/XMLSchema">
<soap:Body>
<UserExists xmlns="http://www.blug.com/wsdl">
<PublicID>
<id>te***@bt.co .uk</id>
<type>1</type>
</PublicID>
</UserExists>
</soap:Body>
</soap:Envelope>

HTTP/1.1 401 UNAUTHORIZED
WWW-Authenticate: Basic realm="Provisio nInterface"
cache-control: no-cache
content-length: 25
content-type: text/html
date: Thu, 22 Jun 2006 12:35:34 GMT
last-modified: Thu, 22 Jun 2006 12:35:34 GMT

POST /ProvisionInterf ace HTTP/1.1
VsDebuggerCausa lityData: <data snipped>
User-Agent: Mozilla/4.0 (compatible; MSIE 6.0; MS Web Services Client
Protocol 1.1.4322.2032)
Content-Type: text/xml; charset=utf-8
SOAPAction: "http://www.blug.com/wsdlUserExists"
Authorization: Basic UFdTSToxMjM0
Content-Length: 387
Expect: 100-continue
Host: 1.2.3.4:50000

<*** message body missing/truncated ***>

The only means I know of influencing the authentication phase is by
attaching a NetworkCredenti al object to the SOAP proxy and the authentication
process is transparent to the application as far as I'm aware.

Has anyone else experienced this problem ?

Thanks,

Tony