This repositories features an example dojo.
The dojo is defined by dojo.yml.
It contains two modules, hello and world.
The module hello features challenges apple and banana.
The module world features challenges earth, mars, and venus.
Each challenge demonstrates different challenge definition capabilities, in an increasing order of feature complexity.
See each challenge's README for further information:
For an example of how you can import another dojo's challenges, see: pwncollege/example-import-dojo.
For instructions on how you can setup automatic dojo updates, using GitHub actions, see: pwncollege/dojo-update.
The flag is located at /flag, and is only readable by root.
The challenge will execute as root.
Nothing else is true.
Do not assume any structure to the flag. It may or may not have a prefix/suffix. It may or may not be 50 bytes long. These things WILL change, and if you rely on them, your challenge WILL break.
The challenge is setuid.
This is how your challenge will execute as root.
What this really means:
- The process will run with an effective user of
root. - The process will run with a real user of
hacker.
While an effective user of root is sufficient for opening the flag, there are some caveats.
When /bin/sh (which is linked to /bin/dash) is run under this, it will immediately set the effective user to the real user (unless the -p flag is provided).
This means that both the effective and real user will be hacker, and the flag will not be accessible.
This affects system, which ultimately just runs /bin/sh.
The challenge can rememedy this by explicitly setting the real user to the effective user:
setreuid(geteuid(), -1)