#!/bin/bash
#
# .---.                  .              .
# |                      |              |
# |--- .--. .-.  .-.  .-.|  .-. .--.--. |.-.  .-. .--.  .-.
# |    |   (.-' (.-' (   | (   )|  |  | |   )(   )|  | (.-'
# '    '     --'  --'  -' -  -' '  '   -' -'   -' '   -  --'
#
#                    Freedom in the Cloud
#
# A script for creating self-signed certificates on Debian

# License
# =======
#
# Copyright (C) 2015-2016 Bob Mottram <bob@robotics.uk.to>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.

PROJECT_NAME='freedombone'

export TEXTDOMAIN=${PROJECT_NAME}-addcert
export TEXTDOMAINDIR="/usr/share/locale"

HOSTNAME=
LETSENCRYPT_HOSTNAME=
COUNTRY_CODE="US"
AREA="Free Speech Zone"
LOCATION="Freedomville"
ORGANISATION="Freedombone"
UNIT="Freedombone Unit"
EXTENSIONS=""
NODH=
DH_KEYLENGTH=2048
INSTALL_DIR=/root/build
LETSENCRYPT_SERVER='https://acme-v01.api.letsencrypt.org/directory'
LETSENCRYPT_REPO='https://github.com/letsencrypt/letsencrypt'

function show_help {
    echo ''
    echo $"${PROJECT_NAME}-addcert -h [hostname] -c [country code] -a [area] -l [location]"
    echo $'                    -o [organisation] -u [unit] --ca "" --nodh ""'
    echo ''
    echo $'Creates a self-signed certificate for the given hostname'
    echo ''
    echo $'     --help                   Show help'
    echo $'  -h --hostname [name]        Hostname'
    echo $'  -e --letsencrypt [hostname] Hostname to use with Lets Encrypt'
    echo $'  -s --server [url]           Lets Encrypt server URL'
    echo $'  -c --country [code]         Optional country code (eg. US, GB, etc)'
    echo $'  -a --area [description]     Optional area description'
    echo $'  -l --location [locn]        Optional location name'
    echo $'  -o --organisation [name]    Optional organisation name'
    echo $'  -u --unit [name]            Optional unit name'
    echo $'     --dhkey [bits]           DH key length in bits'
    echo $'     --nodh ""                Do not calculate DH params'
    echo $'     --ca ""                  Certificate authority cert'
    echo ''
    exit 0
}

while [[ $# > 1 ]]
do
key="$1"

case $key in
    --help)
    show_help
    ;;
    -h|--hostname)
    shift
    HOSTNAME="$1"
    ;;
    -e|--letsencrypt)
    shift
    LETSENCRYPT_HOSTNAME="$1"
    ;;
    -s|--server)
    shift
    LETSENCRYPT_SERVER="$1"
    ;;
    -c|--country)
    shift
    COUNTRY_CODE="$1"
    ;;
    -a|--area)
    shift
    AREA="$1"
    ;;
    -l|--location)
    shift
    LOCATION="$1"
    ;;
    -o|--organisation)
    shift
    ORGANISATION="$1"
    ;;
    -u|--unit)
    shift
    UNIT="$1"
    ;;
    --ca)
    shift
    EXTENSIONS="-extensions v3_ca"
    ORGANISATION="Freedombone-CA"
    ;;
    --nodh)
    shift
    NODH="true"
    ;;
    --dhkey)
    shift
    DH_KEYLENGTH=${1}
    ;;
    *)
    # unknown option
    ;;
esac
shift
done

if [ ! $HOSTNAME ]; then
    if [ ! $LETSENCRYPT_HOSTNAME ]; then
        echo $'No hostname specified'
        exit 5748
    fi
fi

if ! which openssl > /dev/null ;then
    echo $"$0: openssl is not installed, exiting" 1>&2
    exit 5689
fi

if [ ! -d /etc/ssl/mycerts ]; then
    mkdir /etc/ssl/mycerts
fi

CERTFILE=$HOSTNAME

function add_cert_letsencrypt {
    CERTFILE=$LETSENCRYPT_HOSTNAME

    if [ ! -d $INSTALL_DIR ]; then
        mkdir -p $INSTALL_DIR
    fi
    cd $INSTALL_DIR

    # obtain the repo
    if [ ! -d ${INSTALL_DIR}/letsencrypt ]; then
        git clone $LETSENCRYPT_REPO
        if [ ! -d ${INSTALL_DIR}/letsencrypt ]; then
            exit 76283
        fi
    else
        cd ${INSTALL_DIR}/letsencrypt
        git stash
        git pull
    fi

    # stop the web server
    systemctl stop nginx

    cd ${INSTALL_DIR}/letsencrypt
    ./letsencrypt-auto certonly --server $LETSENCRYPT_SERVER --standalone -d $LETSENCRYPT_HOSTNAME --renew-by-default
    if [ ! "$?" = "0" ]; then
        echo $"Failed to install letsencrypt for domain $LETSENCRYPT_HOSTNAME"
        systemctl start nginx
        exit 63216
    fi

    # replace some legacy filenames
    if [ -f /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.bundle.crt ]; then
        mv /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.bundle.crt /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem
    fi
    if [ -f /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.crt ]; then
        mv /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.crt /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem
    fi
    sed -i "s|ssl_certificate /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.bundle.crt|ssl_certificate /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem|g" /etc/nginx/sites-available/$LETSENCRYPT_HOSTNAME
    sed -i "s|ssl_certificate /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.crt|ssl_certificate /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem|g" /etc/nginx/sites-available/$LETSENCRYPT_HOSTNAME

    # link the private key
    if [ -f /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key ]; then
        if [ ! -f /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key.old ]; then
            mv /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key.old
        else
            rm -f /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key
        fi
    fi
    ln -s /etc/letsencrypt/live/${LETSENCRYPT_HOSTNAME}/privkey.pem /etc/ssl/private/${LETSENCRYPT_HOSTNAME}.key

    # link the public key
    if [ -f /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem ]; then
        if [ ! -f /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem.old ]; then
            mv /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem.old
        else
            rm -f /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem
        fi
    fi
    ln -s /etc/letsencrypt/live/${LETSENCRYPT_HOSTNAME}/fullchain.pem /etc/ssl/certs/${LETSENCRYPT_HOSTNAME}.pem

    cp /etc/letsencrypt/live/${LETSENCRYPT_HOSTNAME}/fullchain.pem /etc/ssl/mycerts/${LETSENCRYPT_HOSTNAME}.pem

    systemctl start nginx

    ${PROJECT_NAME}-pin-cert $LETSENCRYPT_HOSTNAME
    if [ ! "$?" = "0" ]; then
        echo $"Certificate for $LETSENCRYPT_HOSTNAME could not be pinned"
        exit 62878
    fi
}

function add_cert_selfsigned {
    if [[ $ORGANISATION == "Freedombone-CA" ]]; then
        CERTFILE="ca-$HOSTNAME"
    fi

    openssl req -x509 ${EXTENSIONS} -nodes -days 3650 -sha256 \
        -subj "/O=$ORGANISATION/OU=$UNIT/C=$COUNTRY_CODE/ST=$AREA/L=$LOCATION/CN=$HOSTNAME" \
        -newkey rsa:4096 -keyout /etc/ssl/private/${CERTFILE}.key \
        -out /etc/ssl/certs/${CERTFILE}.crt
    chmod 400 /etc/ssl/private/${CERTFILE}.key
    chmod 640 /etc/ssl/certs/${CERTFILE}.crt
    cp /etc/ssl/certs/${CERTFILE}.crt /etc/ssl/mycerts

    ${PROJECT_NAME}-pin-cert $CERTFILE
    if [ ! "$?" = "0" ]; then
        echo $"Certificate for $CERTFILE could not be pinned"
        exit 62879
    fi
}

function generate_dh_params {
    if [ ! $NODH ]; then
        if [ ! -f /etc/ssl/certs/${CERTFILE}.dhparam ]; then
            ${PROJECT_NAME}-dhparam -h ${CERTFILE} --fast yes
        fi
    fi
}

function restart_web_server {
    if [ -f /etc/init.d/nginx ]; then
        /etc/init.d/nginx reload
    fi
}

function make_cert_bundle {
    # Create a bundle of your certificates
    cat /etc/ssl/mycerts/*.crt /etc/ssl/mycerts/*.pem > /etc/ssl/${PROJECT_NAME}-bundle.crt
    tar -czvf /etc/ssl/${PROJECT_NAME}-certs.tar.gz /etc/ssl/mycerts/*.crt /etc/ssl/mycerts/*.pem
}

function create_cert {
    if [ $LETSENCRYPT_HOSTNAME ]; then
        add_cert_letsencrypt
    else
        add_cert_selfsigned
    fi
}

create_cert
generate_dh_params
restart_web_server
make_cert_bundle

exit 0