Tripwire Online
Axel came up an idea to write an on-line Tripwire – checking the checksums of files before they are executed. This seems to be quite easily doable using LSM. however, they are a few issues that need to be understood:
- Execution of scripts/perl programs, etc. – cannot prevent it
- Dynamic library loading – how to do it in LSM
- Policy loading – how to read policies in Kernel mode
Hum…. such thing already exists and is an open source project 
Digsig