This is a lightweight script to backup IMAP accounts. It is written in PHP.

There is no restore script yet!

I have a few non-tech-savvy people that I help wrangle their computers. Some have stopped using regular computers and just use phones and tablets with all of their data in the cloud. This means they no longer have a workstation backup. I'm concerned that they might eventually have an event that deletes all of their precious mail from the cloud - with no way to get it back.

This script does the following:

• Log into mail account
• Get a list of messages
• Ignore messages it has already seen... also ignore unread messages
• Download new messages
• (Optionally) encrypt messages for storage with PGP

This is a quick script just to back up data in the event it is needed. It is expeditious and incomplete.

There is no restore function yet!! I will build that if we ever need to recover data.

The script does not download unseen messages, therefore, mail does not get backed up until it is read. This is to prevent the script from marking mail already read. Probably not an issue for most users, but if you don't check mail often, you might not be very well protected.

The script does temporarily write mail to the disk unencrypted. Given that the account password is in plain text, I don't see this as the biggest threat. I might button it up in a future version, but that would make restores more complicated and I want to have restore functionality fully tested first.

The script is designed for one box on one account. If you need multiple boxes, install the script in separate directories. It is clunky, but it is all I needed for my project.

Message IDs may also reset of a box is completely emptied. This could cause some new mail to not be downloaded because the new ID is the same as an old one. None of my users ever throw anything away, so there's not much risk for me... but a real quality program would do a better job.

• Build an Ubuntu system with the needed dependencies

apt-get update
apt-get --yes upgrade
apt-get --yes dist-upgrade
apt-get --yes clean
apt-get --yes autoremove
apt-get --yes install php8.1 php-imap gpg haveged unattended-upgrades

• Clone the repository
• Copy the config-example.php to config.php
• Edit the configuration file
• Create some way to start the program automatically. A daily cron works nicely.
• If using a cron, add it to your favorite cron monitor so you get a notice if it fails.

• Use a workstation or bare-metal server to generate PGP Keys
• Copy the public key to your server and import it (gpg --import < key.asc)
• Get the keyID and put it in your config file. The command gpg --list-keys In the following example, the keyID is C27D5BF2

4096R/C27D5BF2 2015-03-06
uid       [ultimate] Randall Bollig <[email protected]>
sub   4096R/6FA58A3B 2015-03-06

Good encryption relies on quality randomness. If you do not have a physical random generator, you should install a package like haveged to extend your random pool - especially if you are using a virtualized server, container, VPS, cloud server or the like.

Generate your PGP key on a bare-metal server or a workstation as they are more likely to have randomness to draw from. Copy just the public key to the server this script runs on - keep the private key safely somewhere else.