setns-shell

Bring your shell into Rootless Docker containers with you!

Zsh:

$(readelf --string-dump .interp $(which zsh) | awk '/ld-linux/ {print $NF}') --library-path ${module_path} --preload "$(find ${module_path} -iname "*.so" -printf "%p:")" $(which zsh)
module_path=./target/debug zmodload libsetns_shell; zcompile -ac /tmp/full.zwc; setns_shell <PID 1 of container> /tmp/full.zwc
# Then copy/paste output back into shell

TODO

• wrapper script using source
• mount instead of setns into process
• bash support

Caveats and Limitations

• Process that setns is called in doesn't enter designated PID namespace, only remembers it for it's child processes. This is by design of the syscall, and shouldn't really matter unless the running process needs to play with in-container process' without doing a fork-and-exec.