sshbar

#!/bin/bash
# Wrapper script to ssh to a robot. It starts a private instance of ssh-agent
# that makes the user's github key (and only that key) available during the
# session. It also environment variables for the user's git identity, read
# from the local machine's ~/.gituser file.

function valid_ip()
{
    local  ip=$1
    local  stat=1

    if [[ $ip =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
        OIFS=$IFS
        IFS='.'
        ip=($ip)
        IFS=$OIFS
        [[ ${ip[0]} -le 255 && ${ip[1]} -le 255 \
            && ${ip[2]} -le 255 && ${ip[3]} -le 255 ]]
        stat=$?
    fi
    return $stat
}

function usage() {
    echo "Usage:  sshbar [-d <path>] [-s | -k] [-p] [-h] [-v] <destination>"
    echo ""
    echo "Options:"
    echo " -h, --help         Display this help message"
    echo " -d, --key_path     Use <path> for keys *see notes*"
    echo " -s, --secret       Use barkey for authentication (core; port 2222)"
    echo " -k, --classic      Use barkey for authentication (classic; port 22)"
    echo " -p, --payload      Login to payload instead of truck (port 3022 or 3222)"
    echo " -v, --verbose      Verbose"
    echo " -c, --nosshchecks  Use -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no"
    echo " --no-discover      Don't ping the destination or try to find it on the network"
    echo ""
    echo " destination can be robot number (bar<destination>), IP address, or a host."
    echo ""
    echo " Examples:"
    echo " sshbar 672"
    echo "     ssh bar@bar672"
    echo " sshbar -p 672"
    echo "     ssh -i /.ssh/id_rsa-<hostname>-github -p3022 bar@bar672"
    echo " sshbar -ps 672"
    echo "     ssh -i /data/.secrets/barkey -p3222 bar@bar672"
    echo " sshbar -s 672"
    echo "     ssh -i /data/.secrets/barkey -p2222 bar@bar672"
    echo " sshbar -k 672"
    echo "     ssh -i /data/.secrets/barkey -p22 bar@bar672"
    echo " sshbar -kd /home/dnorris/.secrets 672"
    echo "     ssh -i /home/dnorris/.secrets/barkey -p22 bar@bar672"
    echo " sshbar 10.10.39.209"
    echo "     ssh bar@10.10.39.209"
    echo ""
    echo "NOTE: 1. -s and -k options use the barkey for authentication."
    echo "         when not specified, authentication uses"
    echo "         id_rsa-<hostname>-github"
    echo "      2. The defalt path is ~/.ssh when -s or -k are not specified."
    echo "         If -s or -k are specified, the default path is /data/.secrets"
    echo "      3. The env var SECRET_PATH will override the default for both cases."
    exit 1
}

prod=0
payload=0
secret=0
dev=0
user_path=0
verbose=0
ssh_checks=""
discover=1

short_opts="chpskvd:"
long_opts="help,payload,secret,classic,key_path:,nosshchecks,verbose,no-discover"
PARSED_ARGS=$(getopt -a --name "$(basename $0)" --options="${short_opts}" --longoptions="${long_opts}" -- "$@") || usage
eval set -- "$PARSED_ARGS"
while true; do
  case "$1" in
    -c|--nosshchecks)  ssh_checks="-o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no"
        ;;
    -d|--key_path)
        user_path=1
        secret_path="$2"
        shift
      ;;
    -p|--payload)
        payload=1
      ;;
    -s|--secret)
        if [ $dev -eq 1 ] ; then
            usage
        fi
        prod=1
        secret=1
        if [ $user_path -ne 1 ] ; then
          if [ -z $SECRET_PATH ] ; then
              secret_path='/data/.secrets'
          else
              secret_path=$SECRET_PATH
          fi
        fi
      ;;
    -k|--classic)
        if [ $prod -eq 1 ] ; then
            usage
        fi
        dev=1
        secret=1
        if [ $user_path -ne 1 ] ; then
          if [ -z $SECRET_PATH ] ; then
              secret_path='/data/.secrets'
          else
              secret_path=$SECRET_PATH
          fi
        fi
        ;;
    -v|--verbose)
        verbose=1
        ;;
    --no-discover)
        discover=0
        ;;
    -h|--help)
        usage
        return
      ;;
    --)
        shift
        break
      ;;
  esac
  shift
done

if [ -z "$1" ] ; then
    usage
fi

host="${@: -1}"
if valid_ip ${@: -1}; then
    host="${@: -1}"
elif [[ discover -eq 0 ]]; then
    host="${@: -1}"
elif ping -c 1 -W 1 bar${host} > /dev/null 2>&1 ; then
    host=bar${host}
elif ! ping -c 1 -W 1 ${host} > /dev/null 2>&1 ; then
    if [[ ! ${host} =~ ^[0-9]+$ && ! ${host} =~ ^bar[0-9]+$ ]] ; then
        echo "Bad hostname ${host}"
        exit 1
    fi
    host=$(host -l badger-technologies.com ns.badger-technologies.com | grep ${host#bar} | sed 's/.*address //')
    if [[ "${host}" == "" ]]; then
        echo "Unable to find host $1"
        exit 1
    fi
fi

if [ $secret -eq 1 ] || [ $dev -eq 1 ] ; then
    id_file=${secret_path}/barkey
else
    secret_path=$HOME/.ssh
    if [[ -e ${secret_path}/id_ed25519-$(hostname)-github ]] ; then
        id_file=${secret_path}/id_ed25519-$(hostname)-github
    elif [[ -e ${secret_path}/id_rsa-$(hostname)-github ]] ; then
        id_file=${secret_path}/id_rsa-$(hostname)-github
    else
        echo 'Identity File not found in path '${secret_path}
        exit 1
    fi
fi

zshell=0
xfor=0
if [ $prod -eq 1 ] ; then
    if [ $payload -eq 1 ] ; then
        port='3222'
    else
        port='2222'
    fi
elif [ $payload -eq 1 ] ; then
    port='3022'
    zshell=1
    xfor=1
else
    port='22'
    zshell=1
    xfor=1
fi

if [ $zshell -eq 1 ] ; then
    shell='zsh'
else
    shell='bash'
fi

if [ $xfor -eq 1 ] ; then
    options='-X -t -A'
else
    options='-t -A'
fi

uds_addr=$(mktemp --dry-run $XDG_RUNTIME_DIR/ssh-agent-XXXXXX)
git_email=$(sed -n -e 's/^\s\+email\s\?=\s\?//p' < ~/.gituser)
git_name=$(sed -n -e 's/^\s\+name\s\?=\s\?//p' < ~/.gituser | sed -e 's/\s/\\ /')

if [ $verbose -eq 1 ] ; then
    set -x
fi
exec ssh-agent -a $uds_addr ssh ${options} -p${port} -l bar \
    -o IdentityFile=$id_file -o AddKeysToAgent=yes ${ssh_checks} -l bar ${host} \
    GIT_AUTHOR_EMAIL="${git_email}" \
    GIT_COMMITTER_EMAIL="${git_email}" \
    GIT_AUTHOR_NAME="${git_name}" \
    GIT_COMMITTER_NAME="${git_name}" \
    EDITOR=emacs \
    TERM=screen-256color \
    ${shell} ;

set +x