A script to pull SSH keys for a give GitHub user and add those keys to the current users authorized_keys file.

grant_github_user_access

#!/bin/bash
#
# (c)2014 Matt Willsher <matt@willsherpartners.co.uk>
#
# Licensed under GPLv3 http://www.gnu.org/licenses/gpl.txt
#
umask 077

if [[ $EUID == 0 ]]; then
  echo "This script can't be used as root" >&2
  exit 1
fi

tmpfile="/tmp/authkeys.$$"
rc=0

if [[ $# -ne 1 ]]; then
  echo "Please give a github user account as a parameter" >&2
  exit 1
fi

mkdir -m 700 -p ~/.ssh

githubuser=$1

fullname=$( curl -s https://api.github.com/users/${githubuser} | jq -r '.name' )

keycomment="$fullname github:${githubuser}"

curl -s https://github.com/${githubuser}.keys >$tmpfile
if [[ $( stat -c'%s' $tmpfile ) -gt 1 ]]; then
  sed -i -e "s/$/ ${keycomment}/" $tmpfile
  cat $tmpfile >>~/.ssh/authorized_keys
  echo >>~/.ssh/authorized_keys
else
  echo "Couldn't get any keys. Does the github account exist?" >&2
  rc=1
fi

rm $tmpfile

echo "Added keys for $githubuser, full name $fullname"

exit $rc

list_github_user_access

#!/bin/bash
#
# (c)2014 Matt Willsher <matt@willsherpartners.co.uk>
#
# Licensed under GPLv3 http://www.gnu.org/licenses/gpl.txt
#
umask 077

if [[ $EUID == 0 ]]; then
  echo "This script can't be used as root" >&2
  exit 1
fi

cut -d' ' -f1,2 --complement  ~/.ssh/authorized_keys | sort | uniq -c

exit $rc

revoke_github_user_access

#!/bin/bash
#
# (c)2014 Matt Willsher <matt@willsherpartners.co.uk>
#
# Licensed under GPLv3 http://www.gnu.org/licenses/gpl.txt
#
umask 077

if [[ $EUID == 0 ]]; then
  echo "This script can't be used as root" >&2
  exit 1
fi

if [[ $# -ne 1 ]]; then
  echo "Please give a github user account as a parameter" >&2
  exit 1
fi

githubuser=$1

fullname=$( curl -s https://api.github.com/users/${githubuser} | jq -r '.name' )

keycomment="$fullname github:${githubuser}"

grep "${keycomment}" ~/.ssh/authorized_keys >/dev/null
if [[ $? -ne 0 ]]; then
  echo "User $githubuser doesn't have keys in the keys file" >&2
  exit 1
fi

sed -i -e "/${keycomment}/d" ~/.ssh/authorized_keys
rc=$?
if [[ $rc == 0 ]]; then
  echo "Removed keys for $githubuser, full name $fullname"
else
  echo "An error occured removing keys from the authorized_keys file." >&2
fi

exit $rc

This should probably ensure that ~/.ssh is properly created

mkdir ~/.ssh
chmod 700 ~/.ssh

Or better yet just run mkdir -m 700 -p ~/.ssh