dennis@home wrote
Rod Speed wrote

It would be theoretically possible to hide any change if you had the resources and opportunity. For example if you
use hashes to detect changes then someone could alter the hashes.

Not if they arent on that system they cant.

You can't be sure that what you installed wasn't compromised in the first place.

You dont have to install anything on the system being checked.

And you can test whether it can detect changes by making your own changes too.

There are even possible attacks if you compile the C source from scratch. for example..

Yes, but if that system isnt even on the system being protected...

its possible to build a compiler that puts unwanted stuff into programs it compiles.

But they have no control over what compiler you use with a common language.

It is possible to hide these from the source code of the compiler by recognising the compiler and adding the code to
do this when the compiler is compiled.

But they have no control over what compiler you use with a common language.

Before you say this can't be done, did you use a binary to compile your last program or did you do it by hand to
ensure the above wasn't done?

My last program isnt relevant. What matters is what is used to
compile the system that does the checks. With hashes the code
can be so simple that its quite practical to compile it by hand.

You can reduce the risk of this happening but it will always be 0.

Nope. Its perfectly possible to have a risk of 0.

You also put a chainsaw through your computer then?

Dont need to do that.