Testing capability leaks

This is a clone of morello-sdk example showing various compartmentalisation primitives. The only addition I made is in the findcaps subproject, that shows how to obtain capabilities to various mapped regions of the process, through dl_iterate_phdr() library call. This is a function to query all the program headers of the binary that are loaded to memory, so these contain the segments for the main binary, libc, ld (and other libraries if there are any). This library uses a callback function that needs to be provided as an argument to dl_iterate_phdr.

The new stuff is in src/findcaps and src/compartmentalisation

Testing the code

Currently the configuration is set up to run on the morello linux machine, which assumes that the morello sdk is installed in /morello. To compile, simply run make. The compiled files are in build/bin.

To run the code (on plain install)

source /morello/env/morello-sdk ./configure CC=clang --sysroot=$MUSL_HOME make