Question on System.Net.Dns (used with SSL and proxy)

[Asfar Sadewa]

Hello all,

I have a web application written in C# that needs to track the machine name,
ip, and the user name of the accessor.
the application is hosted on a web server using SSL.

i got the user's IP by doing a request.UserHostAddress and then pass the
value to the Dns.GetHostByAddress(ip) method --to get the machine name--,
the IP returned is the proxy used by the users, and the GetHostByAddress()
method returns an error.
Everything is fine if I test it without SSL..

Is there any correct way to obtain user's ip / machine name within an SSL &
proxied environment??

(Sorry if i post this to the wrong group, let me know if I'm wrong)

thanks' in advance,


Asfar

 

[Ben Voigt]

Hello all,

I have a web application written in C# that needs to track the machine
name, ip, and the user name of the accessor.
the application is hosted on a web server using SSL.

i got the user's IP by doing a request.UserHostAddress and then pass the
value to the Dns.GetHostByAddress(ip) method --to get the machine name--,
the IP returned is the proxy used by the users, and the GetHostByAddress()
method returns an error.
Everything is fine if I test it without SSL..

I should think you got the proxy address with no SSL. Often proxies aren't
used for SSL, because the proxy can't process the data, so isn't useful on
many cases.

It's also much more likely that an ISP's proxy server has a reverse DNS
entry, and that the user's workstation address doesn't.

Is there any correct way to obtain user's ip / machine name within an SSL
& proxied environment??

If there is a proxy, then there is no way to get the ultimate user's ip or
machine name without client cooperation. For example, a javascript or
ActiveX control could send back any information, but these run under the
user's control. See "anonymizing web proxy".