Jason Ajmo and Bradford Smith
CS 615 HW6 ec2-backup
May 17, 2018

We chose to use POSIX Shell as our programming language to challenge us to write
a (hopefully) fairly cross-platform Unix program. Ideally the program will run
in any POSIX compliant shell.

We spent some time ensuring our program would be safe from PATH exploits such as
those we used in the class CTF. We messed around with command(1) for a while
before settling on setting PATH inside the script using getconf(1).

We wrote a test script to help us automate our testing but some of the aws
commands took a while to execute, and that combined with the time it took us to
fix issues we found lead to the test script not being very comprehensive.

Overall our biggest issue was probably finding an AWS instance to use for
copying the data. We started out with a Debian AMI but the default user doesn't
have privileges to write to /dev/, so we began looking for instances that had a
default user of root. We spent time trying OmniOS, looked at Turnkey Linux for a
while and spent time using NetBSD. With OmniOS and NetBSD we had issues writing
to the attached volume, so we moved back to a Debian AMI and attempted to switch
to root in the ssh command that copies the data. This did not work either as su
insisted on being called from a tty, which lead us back to NetBSD.