Paccheck tools to control mirrors

There is a serious security issue regarding pacman mirros.
See http://bbs.archbang.org/viewtopic.php?pid=2076#p2076

A partial solution is paccheck.
Install: packer -S paccheck
Use: first synchronize mirrors: sudo pacman -Sy
Then: paccheck --install abc xyz

This will install package abc and xyz and their dependencies, check only those targets (including full mirror compare if configured), and offer to install them. Be sure to read the report to determine if installation is indicated.

How to do a general update with paccheck

When you do paccheck the command pacman -Sy is forwarded to the terminal and the mirrors are checked; when you don't get a warning, - look at the terminal output, you can let it go on; it will go on with pacman -Su ; when you see warnings you have to stop the update manually; fastest way is to close terminal window.
If you did this (stop the update) and want to go on anyway you will have to remove /var/lib/pacman/db.lck to be able to continue.