Re: [obsd] Re: OT using absolute paths in scripts
On Mon, Jan 14, 2013 at 02:16:24AM -0800, Philip Guenther wrote: On Mon, Jan 14, 2013 at 1:14 AM, Jeremie Le Hen jere...@le-hen.org wrote: On Sun, Jan 13, 2013 at 07:12:23PM +0100, Marc Espie wrote: On Sun, Jan 13, 2013 at 11:04:08AM -0600, Maximo Pech wrote: They mandate that on all shell scripts we have to use absolute paths for every single command. That does provide ways less security than setting the PATH to a system-only path at the beginning of your script. Can you elaborate on this? From a security point of view only, this looks to me as a draw. If you consider the portability issues then sure, setting PATH is better. You cut out his next paragraph which gives an example of why: Sure, you invoke programs with an absolute path, but have you checked that those programs don't invoke other programs with execvp ? Hard coding depends on you to actually hard code EVERYWHERE, including in paths and commands passed to *other* commands executed from the script that you write. If you screw up and miss one, you lose. Set PATH and you can't miss one. Oh yeah, sorry, I didn't notice the p suffix, I just thought of execve(2). Thanks for the clarification. Regards, -- Jeremie Le Hen Scientists say the world is made up of Protons, Neutrons and Electrons. They forgot to mention Morons.
Re: [obsd] Re: OT using absolute paths in scripts
On Mon, Jan 14, 2013 at 11:48:04AM +0100, Jeremie Le Hen wrote: On Mon, Jan 14, 2013 at 02:16:24AM -0800, Philip Guenther wrote: On Mon, Jan 14, 2013 at 1:14 AM, Jeremie Le Hen jere...@le-hen.org wrote: On Sun, Jan 13, 2013 at 07:12:23PM +0100, Marc Espie wrote: On Sun, Jan 13, 2013 at 11:04:08AM -0600, Maximo Pech wrote: They mandate that on all shell scripts we have to use absolute paths for every single command. That does provide ways less security than setting the PATH to a system-only path at the beginning of your script. Can you elaborate on this? From a security point of view only, this looks to me as a draw. If you consider the portability issues then sure, setting PATH is better. You cut out his next paragraph which gives an example of why: Sure, you invoke programs with an absolute path, but have you checked that those programs don't invoke other programs with execvp ? Hard coding depends on you to actually hard code EVERYWHERE, including in paths and commands passed to *other* commands executed from the script that you write. If you screw up and miss one, you lose. Set PATH and you can't miss one. Oh yeah, sorry, I didn't notice the p suffix, I just thought of execve(2). That's security, so every little detail counts. Miss one ? You lose, obviously. ;-)
