SMTP Server Help

Diederick · 09-08-2005, 01:25 PM

I want some info on writing a SMTP server, where i can use telnet to to connect to my SMTP server running in the background, and then send the commands as specified by RFC 821. Then using a IDS(Intrusion Detection System) to check if the e-mail was delivered and to pick up error and unautherised access to my SMTP server on port 25. All of this using Java.

Please help, thanx.
Diederick

itsme86 · 09-08-2005, 01:38 PM

Wow, talk about a generic question. You're going to have to be more specific on what you actually need help with. Someone could write pages of information and still not touch on what you're looking for. Have you tried telneting into a real SMTP server yet? What did you learn? What didn't you understand? Be more specific.

EDIT: In the meantime: http://www.catb.org/~esr/faqs/smart-questions.html

Diederick · 09-08-2005, 02:42 PM

OK, the server is listening on port 25 (TCP), now, i know that smtp has several commands like: mail, rcpt, helo...
What is going to happen if i send the server one of those commands, will it understand what is means or will i have to tell it what to do when recieving a specific command?

itsme86 · 09-08-2005, 03:22 PM

You'll have to read in the command, parse it, and then figure out what to do with it. Your server will be a blank slate so you have to define what each command is and write the code to handle each of them.

Diederick · 09-08-2005, 03:49 PM

Thanx, i have started with the server and everything is going will thus far. almost done.

Thanx for your help.

Cheers