Quick & dirty manual
I wrote this tool about 6 years ago in perl (and compiled it into a standalone executable)
so you don't need any other dll's or anything else to use the tool
Basically, the application allows you to test a given smtp server if it would accept third
party relay or not (so if the server is in open relay or not)
It only connects to smtp servers that use tcp port 25, no authentication, no encryption
The application works command line only
When you launch the app without parameters, you'll get the following output :
..:: [ SMTP Open Relay Checker v1.6 ] ::..
Written by Peter Van Eeckhoutte 2008
peter (at) telenet (dot) be
The results of the tests will be saved in a results-file
Option -r is optional. This option allows you to specify the
hostname or IP address of the mail server that is receiving emails
for the email address you've specified with the -a parameter.
It is used in a couple of tests, to see if the target server would
relay to your own smtp server directly.
If you specify -r, then the results of this tests will be
emailed to you.
Option -p is optional. This option allows you to specify which
tests will be used.
The numeric values must be comma seperated.
- If you specify the target server IP address, then your host must
be able to resolve the IP address to a server name.
- v1.6 introduces Module file support
You can create your custom openrelay.mod file
If this file exists in the working directory, then the
application will only run the tests in the openrelay.mod file.
(1 blank space between both addresses)
You can hardcode addresses, and/or use the following variables :
I think most of these options are self-explanatory.
If you run the tool with the proper parameters, it will
execute about 36 open relay checks against a given host
and will in fact attempt to relay an email to you
stating that the relay test was successful, and indicating
the number of the test that caused the server to accept the relay
You can write your own tests as well
Create a text file called openrelay.mod and put it in the same folder
Put one test per line, and first specify the From: address and then the To: address
You can use a couple of variables (as indicated above), so you'll have some flexibility
in writing your own tests
Do NOT use this tool to do something illegal.