This question was asked first at stackoverflow. After 60 views, I got just one response. Now I'm trying serverfault - that's a pertinent topic for here, I guess.
For security reasons, it is desirable to check the integrity of code before execution, avoiding tampered software by an attacker. So, my question is
How to sign executable code and run only trusted software under Linux?
I have read the work of van Doom et al., Design and implementation of signed executables for Linux, and the IBM's TLC (Trusted Linux Client) by Safford & Zohar. TLC uses TPM controller, what is nice, but the paper is from 2005 and I was unable to find current alternatives.
Do you know another option?
UPDATE: And about other OS's? OpenSolaris? BSD family?