Legislation in this country is forcing us to add footers to outgoing messages which specify the company details of the senders. Corporate details could of course be added with signatures, but that leaves the phrasing to end-users, and there’d be no method to enforce using them. Instead, I’ve decided that the only possible point of distribution for these footers will be our MailScanner gateways, as only they guarantee that we catch all sources of outgoing messages, irrespective of which system (MTA) and which client (MUA) the message originates from. The technology I’m applying to add the footers is similar to that which I used for custom whitelisting, although it is a bit more complex. This additional level of complexity arises from the fact that there are a number companies we provide electronic mail service to, and that each user might require a distinct footer. To cater for this, I’m adding a custom attribute type to our OpenLDAP directory servers. This attribute type (footerID) will store an numeric identifier which can be assigned to a user’s LDAP entry. As soon as the custom MailScanner function receives an outgoing message, it will search the directory for the sender’s address and will determine from the footerID which mail footer should be added to the outgoing message. Voila! There is just one tiny detail missing. The code. ;-)

LDAP, DomiNotes, MySQL, Exim, and Linux :: 26 Mar 2007 :: e-mail