Is it possible??

[Zhan Wu]

Dear All,

Sorry to bother you .  Would any one want to help me solve the following question? Is this Function possible?

I want to build a firewall based on linux, and the authentication I want to use is MS NT Domain Authentication(using Samba), So that all the users who already login into the domain can visit the outside via firewall without any other authentication no longer. I am sure I can get the IP address of the use who want send a new connect request(TCP/SYN packet), but How can I know whether this user(IP) already logins into the domain or not?  Is the PDC keep such information like all the IP addresses of the users who already pass the NT Domain authentication?  If not , Is there any other method I can use to realize this function?    What should I do then?   Thank you very much,  I really appreciate your help!

sincerely yours   

Wu Zhan
wuzhan at xajump.edu.cn