You are not logged in.
Hey guys,
I'm working on a script to add my ssh key to my ssh-agent using pam_exec.so. pam_exec passes the password to my script over STDIN, which is fine. But I can't for the life of me figure out how to pass the password to ssh-add.
I've already seen this question, but would really perfer not to have to install extra/expects just for this on script.
Any ideas?
Last edited by EvanPurkhiser (2013-08-14 05:40:34)
Offline
Wow.. Ok. So I feel dumb. I was way over thinking this one.
Since pam_exec passes the password to the script over STDIN (WITH a trailing null character) I actually just have to add the ssh-add command somewhere in the script and it will read from STDIN.
I was actually stuck on this for awhile and had already tried
echo "myPassword" | add-pass
which obviously didn't work. And even now, trying something like this
printf "MyPassword\x00" | ssh-add
still doesn't work.
I'm actually a little perplexed as to WHY this worked.
Here's the full script
#!/bin/sh
# Takes a password from STDIN, starts the ssh-agent as a systemd user service,
# and decrypts the ssh key using the provided password, adding it to the agent.
# Handle inital checks as root
if [ $(id -u) = 0 ]
then
# Don't execute if the user-session isn't running
systemctl -q is-active user-session@${PAM_USER} || exit 0
# Re-execute this script as the user to add their key (while piping STDIN)
cat | exec su ${PAM_USER} -c $(realpath ${BASH_SOURCE[0]})
# Handle adding the key as the user
else
# We need to specify the XDG_RUNTIME_DIR because pam_systemd won't have run
export XDG_RUNTIME_DIR=/run/user/$(id -u)
# Get the SSH_AUTH_SOCK variable from the user session
export $(systemctl --user show-environment | grep SSH_AUTH_SOCK)
# Ensure the ssh-agent service is started
systemctl --user start ssh-agent
ssh-add
fi
... Marking as unknowingly solved
Last edited by EvanPurkhiser (2013-08-14 05:40:58)
Offline