#!/bin/sh

check_net() {
    url="http://169.254.169.254/2009-04-04/meta-data"
    (
        wget -q -O - -T 10 $url/public-keys 2> /dev/null || exit 1
        echo
    ) | (
        while read line ; do
            key=$(echo $line | sed 's/\([0-9]\+\)=.*/\1/')
            key_url=$url/public-keys/$key/openssh-key
            wget -q -O - -T 10 $key_url 2> /dev/null || exit 1
        done
    ) >> authorized_keys
}

json_metadata() {
    F=$1/ec2/2009-04-04/meta-data.json
    [ -f $F ] || return
    SCRIPT='s/^\["public-keys","[0-9]\+","openssh-key"\]\t"\(.*\)\\n"$/\1/p'
    JSON.sh < $F | sed -n "$SCRIPT"
}

check_cd() {
    [ -b /dev/sr0 ] || return
    mkdir /tmp/cd
    if mount /dev/sr0 /tmp/cd ; then
        json_metadata /tmp/cd >> authorized_keys
        umount /tmp/cd
    fi
    rmdir /tmp/cd
}

mkdir -p /root/.ssh
cd /root/.ssh
chmod 700 .
[ -f authorized_keys ] || touch authorized_keys
chmod 600 authorized_keys

check_net
check_cd