On 1/6/19 1:58 PM, Charles Duffy wrote:
Howdy --
I recently had need to dig into the implementation of makepkg --printsrcinfo, and ran into the "running regular expressions against source code" operations in the backend.
Obviously, this is not ideal. Indeed, I've previously written packages (doing unusual and typically-undesirable things, granted) with conditional logic *assuming* that actual execution would be taking place.
I fully appreciate the decision not to try to go with more expansive attempts at emulating bash parsing/execution in the future, but do folks have any thoughts on **really** executing PKGBUILDs in a restricted environment, including execution of the package_* functions?
See a simple sandboxed parser for config files implemented as bash code in code I've written for NixOS at https://github.com/charles-dyfis-net/nixpkgs/blob/f50bfe267a312515d88e86c12a.... We might need a little more complexity here -- using DEBUG traps to avoid "|| exit" logic from aborting, f/e -- but my initial impression is that "more accurate than the current implementation" (and maybe a fair bit faster, if we extract all variables in one subshell per function) is not a hard goal to achieve.
Thoughts?
How would this work considering that it would have to actually do things like cd into $pkgdir, attempt to run /usr/bin/make, and so on? Setting the PATH to something empty won't help with what I'd guess is the primary use of complex functions in the wild, as discussed here: https://bugs.archlinux.org/task/58776 Namely, executing /usr/bin/perl in order to discover its version and implement dependency ranges. -- Eli Schwartz Bug Wrangler and Trusted User