multi-threaded email filter (SMTP traffic)

Project Description:
This project will be building a multi-threaded email filter (SMTP traffic) that runs as a daemon on a linux server (debian).

Ideally the program will be written in C (open to other suggestions) and compiled for maximum speed. The program will accept incoming SMTP connection, doing an analysis of each email message and interacting with a MySQL database.

This program will:
1) INSPECT in inbound SMTP message (identify the IP Address)
2) Look the IP Address up in a database (MySQL)
3) Route the SMTP connection to the appropriate server (route found in config file) that will actually accept the SMTP connection and do the spam filtering.

NOTE: Spam filtering is not part of this project. This project is simply a SMTP router based on Sender's IP Address.

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