Initial version.

Closes csmith/docker-automatic-nginx-letsencrypt#1

Dockerfile

@@ -0,0 +1,14 @@
+FROM ubuntu:xenial 
+MAINTAINER Chris Smith <chris87@gmail.com> 
+
+RUN apt-get update \
+ && apt-get install -y inotify-tools
+
+COPY letsencrypt.sh run.sh config.sh /
+RUN chmod +x /run.sh /letsencrypt.sh
+
+VOLUME ["/letsencrypt", "/dns"]
+
+ENTRYPOINT ["/bin/bash"]
+CMD ["/run.sh"]
+

LICENCE

@@ -0,0 +1,23 @@
+The MIT License (MIT)
+
+letsencrypt.sh copyright (c) 2015 Lukas Schauer
+all other content copyright (c) 2016 Chris Smith
+
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

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+# Let's Encrypt Generic DNS Service
+
+This container uses [letsencrypt.sh](https://github.com/lukas2511/letsencrypt.sh)
+to automatically obtain SSL certs from [Let's Encrypt](https://letsencrypt.org/).
+
+You need to provide a hook that will perform DNS updates on your domains.
+If you use a cloud DNS provider, you're probably better off using
+[letsencrypt-lexicon](https://github.com/csmith/letsencrypt-lexicon).
+
+Multiple domains, as well as SANs, are supported. Certificates will be
+renewed automatically, and obtained automatically as soon as new domains
+are added.
+
+## Usage
+
+### Defining domains
+
+The container defines one volume at `/letsencrypt`, and expects there to be
+a list of domains in `/letsencrypt/domains.txt`. Certificates are output to
+`/letsencrypt/certs/{domain}`.
+
+domains.txt should contain one line per certificate. If you want alternate
+names on the cert, these should be listed after the primary domain. e.g.
+
+```
+example.com www.example.com
+admin.example.com
+```
+
+This will request two certificates: one for example.com with a SAN of
+www.example.com, and a separate one for admin.example.com.
+
+The container uses inotify to monitor the domains.txt file for changes,
+so you can update it while the container is running and changes will be
+automatically applied.
+
+### Hook 
+
+To verify that you own the domain, a TXT record needs to be automatically
+created for it. For this container, you must provide a hook that can do
+the update. See the documentation for
+[letsencrypt.sh](https://github.com/lukas2511/letsencrypt.sh) for details
+on the arguments it takes.
+
+The container expects an executable at `/dns/hook`, and exposes the 
+`/dns` volume for you to mount.
+
+### Other configuration
+
+For testing purposes, you can set the `STAGING` environment variable to
+a non-empty value. This will use the Let's Encrypt staging server, which
+has much more relaxed limits.
+
+You should pass in a contact e-mail address by setting the `EMAIL` env var.
+This is passed on to Let's Encrypt, and may be used for important service
+announcements.
+
+### Running
+
+Here's a full worked example:
+
+```bash
+# The directory we'll use to store the domain list and certificates.
+# You could use a docker volume instead.
+mkdir /tmp/letsencrypt
+echo "domain.com www.domain.com" > /tmp/letsencrypt/domains.txt
+
+docker run -d --restart=always \
+  -e "EMAIL=admin@domain.com" \
+  -e "STAGING=true" \
+  -v /tmp/letsencrypt:/letsencrypt \
+  -v /home/user/my-dns-script:/dns \
+  csmith/letsencrypt-generic:latest
+```
+

config.sh

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+#!/usr/bin/env bash
+
+BASEDIR=/letsencrypt
+CONTACT_EMAIL=$EMAIL
+
+if [ -z ${STAGING+-} ]; then
+  CA="https://acme-v01.api.letsencrypt.org/directory"
+else
+  CA="https://acme-staging.api.letsencrypt.org/directory"
+fi
+

letsencrypt.sh

@@ -0,0 +1,918 @@
+#!/usr/bin/env bash
+
+# letsencrypt.sh by lukas2511
+# Source: https://github.com/lukas2511/letsencrypt.sh
+#
+# This script is licensed under The MIT License (see LICENSE for more information).
+
+set -e
+set -u
+set -o pipefail
+[[ -n "${ZSH_VERSION:-}" ]] && set -o SH_WORD_SPLIT && set +o FUNCTION_ARGZERO
+umask 077 # paranoid umask, we're creating private keys
+
+# Find directory in which this script is stored by traversing all symbolic links
+SOURCE="${0}"
+while [ -h "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
+  DIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
+  SOURCE="$(readlink "$SOURCE")"
+  [[ $SOURCE != /* ]] && SOURCE="$DIR/$SOURCE" # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
+done
+SCRIPTDIR="$( cd -P "$( dirname "$SOURCE" )" && pwd )"
+
+BASEDIR="${SCRIPTDIR}"
+
+# Create (identifiable) temporary files
+_mktemp() {
+  # shellcheck disable=SC2068
+  mktemp ${@:-} "${TMPDIR:-/tmp}/letsencrypt.sh-XXXXXX"
+}
+
+# Check for script dependencies
+check_dependencies() {
+  # just execute some dummy and/or version commands to see if required tools exist and are actually usable
+  openssl version > /dev/null 2>&1 || _exiterr "This script requires an openssl binary."
+  _sed "" < /dev/null > /dev/null 2>&1 || _exiterr "This script requires sed with support for extended (modern) regular expressions."
+  command -v grep > /dev/null 2>&1 || _exiterr "This script requires grep."
+  _mktemp -u > /dev/null 2>&1 || _exiterr "This script requires mktemp."
+
+  # curl returns with an error code in some ancient versions so we have to catch that
+  set +e
+  curl -V > /dev/null 2>&1
+  retcode="$?"
+  set -e
+  if [[ ! "${retcode}" = "0" ]] && [[ ! "${retcode}" = "2" ]]; then
+    _exiterr "This script requires curl."
+  fi
+}
+
+# Setup default config values, search for and load configuration files
+load_config() {
+  # Check for config in various locations
+  if [[ -z "${CONFIG:-}" ]]; then
+    for check_config in "/etc/letsencrypt.sh" "/usr/local/etc/letsencrypt.sh" "${PWD}" "${SCRIPTDIR}"; do
+      if [[ -e "${check_config}/config.sh" ]]; then
+        BASEDIR="${check_config}"
+        CONFIG="${check_config}/config.sh"
+        break
+      fi
+    done
+  fi
+
+  # Default values
+  CA="https://acme-v01.api.letsencrypt.org/directory"
+  LICENSE="https://letsencrypt.org/documents/LE-SA-v1.0.1-July-27-2015.pdf"
+  CHALLENGETYPE="http-01"
+  CONFIG_D=
+  HOOK=
+  HOOK_CHAIN="no"
+  RENEW_DAYS="30"
+  ACCOUNT_KEY=
+  ACCOUNT_KEY_JSON=
+  KEYSIZE="4096"
+  WELLKNOWN=
+  PRIVATE_KEY_RENEW="yes"
+  KEY_ALGO=rsa
+  OPENSSL_CNF="$(openssl version -d | cut -d\" -f2)/openssl.cnf"
+  CONTACT_EMAIL=
+  LOCKFILE=
+
+  if [[ -z "${CONFIG:-}" ]]; then
+    echo "#" >&2
+    echo "# !! WARNING !! No main config file found, using default config!" >&2
+    echo "#" >&2
+  elif [[ -e "${CONFIG}" ]]; then
+    echo "# INFO: Using main config file ${CONFIG}"
+    BASEDIR="$(dirname "${CONFIG}")"
+    # shellcheck disable=SC1090
+    . "${CONFIG}"
+  else
+    _exiterr "Specified config file doesn't exist."
+  fi
+
+  if [[ -n "${CONFIG_D}" ]]; then
+    if [[ ! -d "${CONFIG_D}" ]]; then
+      _exiterr "The path ${CONFIG_D} specified for CONFIG_D does not point to a directory." >&2
+    fi
+
+    for check_config_d in "${CONFIG_D}"/*.sh; do
+      if [[ ! -e "${check_config_d}" ]]; then
+        echo "# !! WARNING !! Extra configuration directory ${CONFIG_D} exists, but no configuration found in it." >&2
+        break
+      elif [[ -f "${check_config_d}" ]] && [[ -r "${check_config_d}" ]]; then
+        echo "# INFO: Using additional config file ${check_config_d}"
+        # shellcheck disable=SC1090
+        . "${check_config_d}"
+      else
+        _exiterr "Specified additional config ${check_config_d} is not readable or not a file at all." >&2
+      fi
+   done
+  fi
+
+  # Remove slash from end of BASEDIR. Mostly for cleaner outputs, doesn't change functionality.
+  BASEDIR="${BASEDIR%%/}"
+
+  # Check BASEDIR and set default variables
+  [[ -d "${BASEDIR}" ]] || _exiterr "BASEDIR does not exist: ${BASEDIR}"
+
+  [[ -z "${ACCOUNT_KEY}" ]] && ACCOUNT_KEY="${BASEDIR}/private_key.pem"
+  [[ -z "${ACCOUNT_KEY_JSON}" ]] && ACCOUNT_KEY_JSON="${BASEDIR}/private_key.json"
+  [[ -z "${WELLKNOWN}" ]] && WELLKNOWN="${BASEDIR}/.acme-challenges"
+  [[ -z "${LOCKFILE}" ]] && LOCKFILE="${BASEDIR}/lock"
+
+  [[ -n "${PARAM_HOOK:-}" ]] && HOOK="${PARAM_HOOK}"
+  [[ -n "${PARAM_CHALLENGETYPE:-}" ]] && CHALLENGETYPE="${PARAM_CHALLENGETYPE}"
+  [[ -n "${PARAM_KEY_ALGO:-}" ]] && KEY_ALGO="${PARAM_KEY_ALGO}"
+
+  [[ "${CHALLENGETYPE}" =~ (http-01|dns-01) ]] || _exiterr "Unknown challenge type ${CHALLENGETYPE}... can not continue."
+  if [[ "${CHALLENGETYPE}" = "dns-01" ]] && [[ -z "${HOOK}" ]]; then
+   _exiterr "Challenge type dns-01 needs a hook script for deployment... can not continue."
+  fi
+  [[ "${KEY_ALGO}" =~ ^(rsa|prime256v1|secp384r1)$ ]] || _exiterr "Unknown public key algorithm ${KEY_ALGO}... can not continue."
+}
+
+# Initialize system
+init_system() {
+  load_config
+
+  # Lockfile handling (prevents concurrent access)
+  LOCKDIR="$(dirname "${LOCKFILE}")"
+  [[ -w "${LOCKDIR}" ]] || _exiterr "Directory ${LOCKDIR} for LOCKFILE ${LOCKFILE} is not writable, aborting."
+  ( set -C; date > "${LOCKFILE}" ) 2>/dev/null || _exiterr "Lock file '${LOCKFILE}' present, aborting."
+  remove_lock() { rm -f "${LOCKFILE}"; }
+  trap 'remove_lock' EXIT
+
+  # Get CA URLs
+  CA_DIRECTORY="$(http_request get "${CA}")"
+  CA_NEW_CERT="$(printf "%s" "${CA_DIRECTORY}" | get_json_string_value new-cert)" &&
+  CA_NEW_AUTHZ="$(printf "%s" "${CA_DIRECTORY}" | get_json_string_value new-authz)" &&
+  CA_NEW_REG="$(printf "%s" "${CA_DIRECTORY}" | get_json_string_value new-reg)" &&
+  # shellcheck disable=SC2015
+  CA_REVOKE_CERT="$(printf "%s" "${CA_DIRECTORY}" | get_json_string_value revoke-cert)" ||
+  _exiterr "Problem retrieving ACME/CA-URLs, check if your configured CA points to the directory entrypoint."
+
+  # Export some environment variables to be used in hook script
+  export WELLKNOWN BASEDIR CONFIG
+
+  # Checking for private key ...
+  register_new_key="no"
+  if [[ -n "${PARAM_ACCOUNT_KEY:-}" ]]; then
+    # a private key was specified from the command line so use it for this run
+    echo "Using private key ${PARAM_ACCOUNT_KEY} instead of account key"
+    ACCOUNT_KEY="${PARAM_ACCOUNT_KEY}"
+    ACCOUNT_KEY_JSON="${PARAM_ACCOUNT_KEY}.json"
+  else
+    # Check if private account key exists, if it doesn't exist yet generate a new one (rsa key)
+    if [[ ! -e "${ACCOUNT_KEY}" ]]; then
+      echo "+ Generating account key..."
+      _openssl genrsa -out "${ACCOUNT_KEY}" "${KEYSIZE}"
+      register_new_key="yes"
+    fi
+  fi
+  openssl rsa -in "${ACCOUNT_KEY}" -check 2>/dev/null > /dev/null || _exiterr "Account key is not valid, can not continue."
+
+  # Get public components from private key and calculate thumbprint
+  pubExponent64="$(printf '%x' "$(openssl rsa -in "${ACCOUNT_KEY}" -noout -text | awk '/publicExponent/ {print $2}')" | hex2bin | urlbase64)"
+  pubMod64="$(openssl rsa -in "${ACCOUNT_KEY}" -noout -modulus | cut -d'=' -f2 | hex2bin | urlbase64)"
+
+  thumbprint="$(printf '{"e":"%s","kty":"RSA","n":"%s"}' "${pubExponent64}" "${pubMod64}" | openssl dgst -sha256 -binary | urlbase64)"
+
+  # If we generated a new private key in the step above we have to register it with the acme-server
+  if [[ "${register_new_key}" = "yes" ]]; then
+    echo "+ Registering account key with letsencrypt..."
+    [[ ! -z "${CA_NEW_REG}" ]] || _exiterr "Certificate authority doesn't allow registrations."
+    # If an email for the contact has been provided then adding it to the registration request
+    if [[ -n "${CONTACT_EMAIL}" ]]; then
+      signed_request "${CA_NEW_REG}" '{"resource": "new-reg", "contact":["mailto:'"${CONTACT_EMAIL}"'"], "agreement": "'"$LICENSE"'"}' > "${ACCOUNT_KEY_JSON}"
+    else
+      signed_request "${CA_NEW_REG}" '{"resource": "new-reg", "agreement": "'"$LICENSE"'"}' > "${ACCOUNT_KEY_JSON}"
+    fi
+  fi
+
+  if [[ "${CHALLENGETYPE}" = "http-01" && ! -d "${WELLKNOWN}" ]]; then
+      _exiterr "WELLKNOWN directory doesn't exist, please create ${WELLKNOWN} and set appropriate permissions."
+  fi
+}
+
+# Different sed version for different os types...
+_sed() {
+  if [[ "${OSTYPE}" = "Linux" ]]; then
+    sed -r "${@}"
+  else
+    sed -E "${@}"
+  fi
+}
+
+# Print error message and exit with error
+_exiterr() {
+  echo "ERROR: ${1}" >&2
+  exit 1
+}
+
+# Remove newlines and whitespace from json
+clean_json() {
+  tr -d '\r\n' | _sed -e 's/ +/ /g' -e 's/\{ /{/g' -e 's/ \}/}/g' -e 's/\[ /[/g' -e 's/ \]/]/g'
+}
+
+# Encode data as url-safe formatted base64
+urlbase64() {
+  # urlbase64: base64 encoded string with '+' replaced with '-' and '/' replaced with '_'
+  openssl base64 -e | tr -d '\n\r' | _sed -e 's:=*$::g' -e 'y:+/:-_:'
+}
+
+# Convert hex string to binary data
+hex2bin() {
+  # Remove spaces, add leading zero, escape as hex string and parse with printf
+  printf -- "$(cat | _sed -e 's/[[:space:]]//g' -e 's/^(.(.{2})*)$/0\1/' -e 's/(.{2})/\\x\1/g')"
+}
+
+# Get string value from json dictionary
+get_json_string_value() {
+  local filter
+  filter=$(printf 's/.*"%s": *"\([^"]*\)".*/\\1/p' "$1")
+  sed -n "${filter}"
+}
+
+# OpenSSL writes to stderr/stdout even when there are no errors. So just
+# display the output if the exit code was != 0 to simplify debugging.
+_openssl() {
+  set +e
+  out="$(openssl "${@}" 2>&1)"
+  res=$?
+  set -e
+  if [[ ${res} -ne 0 ]]; then
+    echo "  + ERROR: failed to run $* (Exitcode: ${res})" >&2
+    echo >&2
+    echo "Details:" >&2
+    echo "${out}" >&2
+    echo >&2
+    exit ${res}
+  fi
+}
+
+# Send http(s) request with specified method
+http_request() {
+  tempcont="$(_mktemp)"
+
+  set +e
+  if [[ "${1}" = "head" ]]; then
+    statuscode="$(curl -s -w "%{http_code}" -o "${tempcont}" "${2}" -I)"
+    curlret="${?}"
+  elif [[ "${1}" = "get" ]]; then
+    statuscode="$(curl -s -w "%{http_code}" -o "${tempcont}" "${2}")"
+    curlret="${?}"
+  elif [[ "${1}" = "post" ]]; then
+    statuscode="$(curl -s -w "%{http_code}" -o "${tempcont}" "${2}" -d "${3}")"
+    curlret="${?}"
+  else
+    set -e
+    _exiterr "Unknown request method: ${1}"
+  fi
+  set -e
+
+  if [[ ! "${curlret}" = "0" ]]; then
+    _exiterr "Problem connecting to server (curl returned with ${curlret})"
+  fi
+
+  if [[ ! "${statuscode:0:1}" = "2" ]]; then
+    echo "  + ERROR: An error occurred while sending ${1}-request to ${2} (Status ${statuscode})" >&2
+    echo >&2
+    echo "Details:" >&2
+    cat "${tempcont}" >&2
+    rm -f "${tempcont}"
+
+    # Wait for hook script to clean the challenge if used
+    if [[ -n "${HOOK}" ]] && [[ "${HOOK_CHAIN}" != "yes" ]] && [[ -n "${challenge_token:+set}" ]]; then
+      "${HOOK}" "clean_challenge" '' "${challenge_token}" "${keyauth}"
+    fi
+
+    # remove temporary domains.txt file if used
+    [[ -n "${PARAM_DOMAIN:-}" && -n "${DOMAINS_TXT:-}" ]] && rm "${DOMAINS_TXT}"
+    exit 1
+  fi
+
+  cat "${tempcont}"
+  rm -f "${tempcont}"
+}
+
+# Send signed request
+signed_request() {
+  # Encode payload as urlbase64
+  payload64="$(printf '%s' "${2}" | urlbase64)"
+
+  # Retrieve nonce from acme-server
+  nonce="$(http_request head "${CA}" | grep Replay-Nonce: | awk -F ': ' '{print $2}' | tr -d '\n\r')"
+
+  # Build header with just our public key and algorithm information
+  header='{"alg": "RS256", "jwk": {"e": "'"${pubExponent64}"'", "kty": "RSA", "n": "'"${pubMod64}"'"}}'
+
+  # Build another header which also contains the previously received nonce and encode it as urlbase64
+  protected='{"alg": "RS256", "jwk": {"e": "'"${pubExponent64}"'", "kty": "RSA", "n": "'"${pubMod64}"'"}, "nonce": "'"${nonce}"'"}'
+  protected64="$(printf '%s' "${protected}" | urlbase64)"
+
+  # Sign header with nonce and our payload with our private key and encode signature as urlbase64
+  signed64="$(printf '%s' "${protected64}.${payload64}" | openssl dgst -sha256 -sign "${ACCOUNT_KEY}" | urlbase64)"
+
+  # Send header + extended header + payload + signature to the acme-server
+  data='{"header": '"${header}"', "protected": "'"${protected64}"'", "payload": "'"${payload64}"'", "signature": "'"${signed64}"'"}'
+
+  http_request post "${1}" "${data}"
+}
+
+# Extracts all subject names from a CSR
+# Outputs either the CN, or the SANs, one per line
+extract_altnames() {
+  csr="${1}" # the CSR itself (not a file)
+
+  if ! <<<"${csr}" openssl req -verify -noout 2>/dev/null; then
+    _exiterr "Certificate signing request isn't valid"
+  fi
+
+  reqtext="$( <<<"${csr}" openssl req -noout -text )"
+  if <<<"${reqtext}" grep -q '^[[:space:]]*X509v3 Subject Alternative Name:[[:space:]]*$'; then
+    # SANs used, extract these
+    altnames="$( <<<"${reqtext}" grep -A1 '^[[:space:]]*X509v3 Subject Alternative Name:[[:space:]]*$' | tail -n1 )"
+    # split to one per line:
+    # shellcheck disable=SC1003
+    altnames="$( <<<"${altnames}" _sed -e 's/^[[:space:]]*//; s/, /\'$'\n''/g' )"
+    # we can only get DNS: ones signed
+    if grep -qv '^DNS:' <<<"${altnames}"; then
+      _exiterr "Certificate signing request contains non-DNS Subject Alternative Names"
+    fi
+    # strip away the DNS: prefix
+    altnames="$( <<<"${altnames}" _sed -e 's/^DNS://' )"
+    echo "${altnames}"
+
+  else
+    # No SANs, extract CN
+    altnames="$( <<<"${reqtext}" grep '^[[:space:]]*Subject:' | _sed -e 's/.* CN=([^ /,]*).*/\1/' )"
+    echo "${altnames}"
+  fi
+}
+
+# Create certificate for domain(s) and outputs it FD 3
+sign_csr() {
+  csr="${1}" # the CSR itself (not a file)
+
+  if { true >&3; } 2>/dev/null; then
+    : # fd 3 looks OK
+  else
+    _exiterr "sign_csr: FD 3 not open"
+  fi
+
+  shift 1 || true
+  altnames="${*:-}"
+  if [ -z "${altnames}" ]; then
+    altnames="$( extract_altnames "${csr}" )"
+  fi
+
+  if [[ -z "${CA_NEW_AUTHZ}" ]] || [[ -z "${CA_NEW_CERT}" ]]; then
+    _exiterr "Certificate authority doesn't allow certificate signing"
+  fi
+
+  local idx=0
+  if [[ -n "${ZSH_VERSION:-}" ]]; then
+    local -A challenge_uris challenge_tokens keyauths deploy_args
+  else
+    local -a challenge_uris challenge_tokens keyauths deploy_args
+  fi
+
+  # Request challenges
+  for altname in ${altnames}; do
+    # Ask the acme-server for new challenge token and extract them from the resulting json block
+    echo " + Requesting challenge for ${altname}..."
+    response="$(signed_request "${CA_NEW_AUTHZ}" '{"resource": "new-authz", "identifier": {"type": "dns", "value": "'"${altname}"'"}}' | clean_json)"
+
+    challenges="$(printf '%s\n' "${response}" | sed -n 's/.*\("challenges":[^\[]*\[[^]]*]\).*/\1/p')"
+    repl=$'\n''{' # fix syntax highlighting in Vim
+    challenge="$(printf "%s" "${challenges//\{/${repl}}" | grep \""${CHALLENGETYPE}"\")"
+    challenge_token="$(printf '%s' "${challenge}" | get_json_string_value token | _sed 's/[^A-Za-z0-9_\-]/_/g')"
+    challenge_uri="$(printf '%s' "${challenge}" | get_json_string_value uri)"
+
+    if [[ -z "${challenge_token}" ]] || [[ -z "${challenge_uri}" ]]; then
+      _exiterr "Can't retrieve challenges (${response})"
+    fi
+
+    # Challenge response consists of the challenge token and the thumbprint of our public certificate
+    keyauth="${challenge_token}.${thumbprint}"
+
+    case "${CHALLENGETYPE}" in
+      "http-01")
+        # Store challenge response in well-known location and make world-readable (so that a webserver can access it)
+        printf '%s' "${keyauth}" > "${WELLKNOWN}/${challenge_token}"
+        chmod a+r "${WELLKNOWN}/${challenge_token}"
+        keyauth_hook="${keyauth}"
+        ;;
+      "dns-01")
+        # Generate DNS entry content for dns-01 validation
+        keyauth_hook="$(printf '%s' "${keyauth}" | openssl dgst -sha256 -binary | urlbase64)"
+        ;;
+    esac
+
+    challenge_uris[${idx}]="${challenge_uri}"
+    keyauths[${idx}]="${keyauth}"
+    challenge_tokens[${idx}]="${challenge_token}"
+    # Note: assumes args will never have spaces!
+    deploy_args[${idx}]="${altname} ${challenge_token} ${keyauth_hook}"
+    idx=$((idx+1))
+  done
+
+  # Wait for hook script to deploy the challenges if used
+  # shellcheck disable=SC2068
+  [[ -n "${HOOK}" ]] && [[ "${HOOK_CHAIN}" = "yes" ]] && "${HOOK}" "deploy_challenge" ${deploy_args[@]}
+
+  # Respond to challenges
+  idx=0
+  for altname in ${altnames}; do
+    challenge_token="${challenge_tokens[${idx}]}"
+    keyauth="${keyauths[${idx}]}"
+
+    # Wait for hook script to deploy the challenge if used
+    # shellcheck disable=SC2086
+    [[ -n "${HOOK}" ]] && [[ "${HOOK_CHAIN}" != "yes" ]] && "${HOOK}" "deploy_challenge" ${deploy_args[${idx}]}
+
+    # Ask the acme-server to verify our challenge and wait until it is no longer pending
+    echo " + Responding to challenge for ${altname}..."
+    result="$(signed_request "${challenge_uris[${idx}]}" '{"resource": "challenge", "keyAuthorization": "'"${keyauth}"'"}' | clean_json)"
+
+    reqstatus="$(printf '%s\n' "${result}" | get_json_string_value status)"
+
+    while [[ "${reqstatus}" = "pending" ]]; do
+      sleep 1
+      result="$(http_request get "${challenge_uris[${idx}]}")"
+      reqstatus="$(printf '%s\n' "${result}" | get_json_string_value status)"
+    done
+
+    [[ "${CHALLENGETYPE}" = "http-01" ]] && rm -f "${WELLKNOWN}/${challenge_token}"
+
+    # Wait for hook script to clean the challenge if used
+    if [[ -n "${HOOK}" ]] && [[ "${HOOK_CHAIN}" != "yes" ]] && [[ -n "${challenge_token}" ]]; then
+      # shellcheck disable=SC2086
+      "${HOOK}" "clean_challenge" ${deploy_args[${idx}]}
+    fi
+    idx=$((idx+1))
+
+    if [[ "${reqstatus}" = "valid" ]]; then
+      echo " + Challenge is valid!"
+    else
+      break
+    fi
+  done
+
+  # Wait for hook script to clean the challenges if used
+  # shellcheck disable=SC2068
+  [[ -n "${HOOK}" ]] && [[ "${HOOK_CHAIN}" = "yes" ]] && "${HOOK}" "clean_challenge" ${deploy_args[@]}
+
+  if [[ "${reqstatus}" != "valid" ]]; then
+    # Clean up any remaining challenge_tokens if we stopped early
+    if [[ "${CHALLENGETYPE}" = "http-01" ]]; then
+      while [ ${idx} -lt ${#challenge_tokens[@]} ]; do
+        rm -f "${WELLKNOWN}/${challenge_tokens[${idx}]}"
+        idx=$((idx+1))
+      done
+    fi
+
+    _exiterr "Challenge is invalid! (returned: ${reqstatus}) (result: ${result})"
+  fi
+
+  # Finally request certificate from the acme-server and store it in cert-${timestamp}.pem and link from cert.pem
+  echo " + Requesting certificate..."
+  csr64="$( <<<"${csr}" openssl req -outform DER | urlbase64)"
+  crt64="$(signed_request "${CA_NEW_CERT}" '{"resource": "new-cert", "csr": "'"${csr64}"'"}' | openssl base64 -e)"
+  crt="$( printf -- '-----BEGIN CERTIFICATE-----\n%s\n-----END CERTIFICATE-----\n' "${crt64}" )"
+
+  # Try to load the certificate to detect corruption
+  echo " + Checking certificate..."
+  _openssl x509 -text <<<"${crt}"
+
+  echo "${crt}" >&3
+
+  unset challenge_token
+  echo " + Done!"
+}
+
+# Create certificate for domain(s)
+sign_domain() {
+  domain="${1}"
+  altnames="${*}"
+  timestamp="$(date +%s)"
+
+  echo " + Signing domains..."
+  if [[ -z "${CA_NEW_AUTHZ}" ]] || [[ -z "${CA_NEW_CERT}" ]]; then
+    _exiterr "Certificate authority doesn't allow certificate signing"
+  fi
+
+  # If there is no existing certificate directory => make it
+  if [[ ! -e "${BASEDIR}/certs/${domain}" ]]; then
+    echo " + Creating new directory ${BASEDIR}/certs/${domain} ..."
+    mkdir -p "${BASEDIR}/certs/${domain}"
+  fi
+
+  privkey="privkey.pem"
+  # generate a new private key if we need or want one
+  if [[ ! -r "${BASEDIR}/certs/${domain}/privkey.pem" ]] || [[ "${PRIVATE_KEY_RENEW}" = "yes" ]]; then
+    echo " + Generating private key..."
+    privkey="privkey-${timestamp}.pem"
+    case "${KEY_ALGO}" in
+      rsa) _openssl genrsa -out "${BASEDIR}/certs/${domain}/privkey-${timestamp}.pem" "${KEYSIZE}";;
+      prime256v1|secp384r1) _openssl ecparam -genkey -name "${KEY_ALGO}" -out "${BASEDIR}/certs/${domain}/privkey-${timestamp}.pem";;
+    esac
+  fi
+
+  # Generate signing request config and the actual signing request
+  echo " + Generating signing request..."
+  SAN=""
+  for altname in ${altnames}; do
+    SAN+="DNS:${altname}, "
+  done
+  SAN="${SAN%%, }"
+  local tmp_openssl_cnf
+  tmp_openssl_cnf="$(_mktemp)"
+  cat "${OPENSSL_CNF}" > "${tmp_openssl_cnf}"
+  printf "[SAN]\nsubjectAltName=%s" "${SAN}" >> "${tmp_openssl_cnf}"
+  openssl req -new -sha256 -key "${BASEDIR}/certs/${domain}/${privkey}" -out "${BASEDIR}/certs/${domain}/cert-${timestamp}.csr" -subj "/CN=${domain}/" -reqexts SAN -config "${tmp_openssl_cnf}"
+  rm -f "${tmp_openssl_cnf}"
+
+  crt_path="${BASEDIR}/certs/${domain}/cert-${timestamp}.pem"
+  # shellcheck disable=SC2086
+  sign_csr "$(< "${BASEDIR}/certs/${domain}/cert-${timestamp}.csr" )" ${altnames} 3>"${crt_path}"
+
+  # Create fullchain.pem
+  echo " + Creating fullchain.pem..."
+  cat "${crt_path}" > "${BASEDIR}/certs/${domain}/fullchain-${timestamp}.pem"
+  http_request get "$(openssl x509 -in "${BASEDIR}/certs/${domain}/cert-${timestamp}.pem" -noout -text | grep 'CA Issuers - URI:' | cut -d':' -f2-)" > "${BASEDIR}/certs/${domain}/chain-${timestamp}.pem"
+  if ! grep -q "BEGIN CERTIFICATE" "${BASEDIR}/certs/${domain}/chain-${timestamp}.pem"; then
+    openssl x509 -in "${BASEDIR}/certs/${domain}/chain-${timestamp}.pem" -inform DER -out "${BASEDIR}/certs/${domain}/chain-${timestamp}.pem" -outform PEM
+  fi
+  cat "${BASEDIR}/certs/${domain}/chain-${timestamp}.pem" >> "${BASEDIR}/certs/${domain}/fullchain-${timestamp}.pem"
+
+  # Update symlinks
+  [[ "${privkey}" = "privkey.pem" ]] || ln -sf "privkey-${timestamp}.pem" "${BASEDIR}/certs/${domain}/privkey.pem"
+
+  ln -sf "chain-${timestamp}.pem" "${BASEDIR}/certs/${domain}/chain.pem"
+  ln -sf "fullchain-${timestamp}.pem" "${BASEDIR}/certs/${domain}/fullchain.pem"
+  ln -sf "cert-${timestamp}.csr" "${BASEDIR}/certs/${domain}/cert.csr"
+  ln -sf "cert-${timestamp}.pem" "${BASEDIR}/certs/${domain}/cert.pem"
+
+  # Wait for hook script to clean the challenge and to deploy cert if used
+  export KEY_ALGO
+  [[ -n "${HOOK}" ]] && "${HOOK}" "deploy_cert" "${domain}" "${BASEDIR}/certs/${domain}/privkey.pem" "${BASEDIR}/certs/${domain}/cert.pem" "${BASEDIR}/certs/${domain}/fullchain.pem" "${BASEDIR}/certs/${domain}/chain.pem" "${timestamp}"
+
+  unset challenge_token
+  echo " + Done!"
+}
+
+# Usage: --cron (-c)
+# Description: Sign/renew non-existant/changed/expiring certificates.
+command_sign_domains() {
+  init_system
+
+  if [[ -n "${PARAM_DOMAIN:-}" ]]; then
+    DOMAINS_TXT="$(_mktemp)"
+    printf -- "${PARAM_DOMAIN}" > "${DOMAINS_TXT}"
+  elif [[ -e "${BASEDIR}/domains.txt" ]]; then
+    DOMAINS_TXT="${BASEDIR}/domains.txt"
+  else
+    _exiterr "domains.txt not found and --domain not given"
+  fi
+
+  # Generate certificates for all domains found in domains.txt. Check if existing certificate are about to expire
+  ORIGIFS="${IFS}"
+  IFS=$'\n'
+  for line in $(<"${DOMAINS_TXT}" tr -d '\r' | tr '[:upper:]' '[:lower:]' | _sed -e 's/^[[:space:]]*//g' -e 's/[[:space:]]*$//g' -e 's/[[:space:]]+/ /g' | (grep -vE '^(#|$)' || true)); do
+    IFS="${ORIGIFS}"
+    domain="$(printf '%s\n' "${line}" | cut -d' ' -f1)"
+    morenames="$(printf '%s\n' "${line}" | cut -s -d' ' -f2-)"
+    cert="${BASEDIR}/certs/${domain}/cert.pem"
+
+    force_renew="${PARAM_FORCE:-no}"
+
+    if [[ -z "${morenames}" ]];then
+      echo "Processing ${domain}"
+    else
+      echo "Processing ${domain} with alternative names: ${morenames}"
+    fi
+
+    if [[ -e "${cert}" ]]; then
+      printf " + Checking domain name(s) of existing cert..."
+
+      certnames="$(openssl x509 -in "${cert}" -text -noout | grep DNS: | _sed 's/DNS://g' | tr -d ' ' | tr ',' '\n' | sort -u | tr '\n' ' ' | _sed 's/ $//')"
+      givennames="$(echo "${domain}" "${morenames}"| tr ' ' '\n' | sort -u | tr '\n' ' ' | _sed 's/ $//' | _sed 's/^ //')"
+
+      if [[ "${certnames}" = "${givennames}" ]]; then
+        echo " unchanged."
+      else
+        echo " changed!"
+        echo " + Domain name(s) are not matching!"
+        echo " + Names in old certificate: ${certnames}"
+        echo " + Configured names: ${givennames}"
+        echo " + Forcing renew."
+        force_renew="yes"
+      fi
+    fi
+
+    if [[ -e "${cert}" ]]; then
+      echo " + Checking expire date of existing cert..."
+      valid="$(openssl x509 -enddate -noout -in "${cert}" | cut -d= -f2- )"
+
+      printf " + Valid till %s " "${valid}"
+      if openssl x509 -checkend $((RENEW_DAYS * 86400)) -noout -in "${cert}"; then
+        printf "(Longer than %d days). " "${RENEW_DAYS}"
+        if [[ "${force_renew}" = "yes" ]]; then
+          echo "Ignoring because renew was forced!"
+        else
+          # Certificate-Names unchanged and cert is still valid
+          echo "Skipping renew!"
+          [[ -n "${HOOK}" ]] && "${HOOK}" "unchanged_cert" "${domain}" "${BASEDIR}/certs/${domain}/privkey.pem" "${BASEDIR}/certs/${domain}/cert.pem" "${BASEDIR}/certs/${domain}/fullchain.pem" "${BASEDIR}/certs/${domain}/chain.pem"
+          continue
+        fi
+      else
+        echo "(Less than ${RENEW_DAYS} days). Renewing!"
+      fi
+    fi
+
+    # shellcheck disable=SC2086
+    sign_domain ${line}
+  done
+
+  # remove temporary domains.txt file if used
+  [[ -n "${PARAM_DOMAIN:-}" ]] && rm -f "${DOMAINS_TXT}"
+
+  exit 0
+}
+
+# Usage: --signcsr (-s) path/to/csr.pem
+# Description: Sign a given CSR, output CRT on stdout (advanced usage)
+command_sign_csr() {
+  # redirect stdout to stderr
+  # leave stdout over at fd 3 to output the cert
+  exec 3>&1 1>&2
+
+  init_system
+
+  csrfile="${1}"
+  if [ ! -r "${csrfile}" ]; then
+    _exiterr "Could not read certificate signing request ${csrfile}"
+  fi
+
+  sign_csr "$(< "${csrfile}" )"
+
+  exit 0
+}
+
+# Usage: --revoke (-r) path/to/cert.pem
+# Description: Revoke specified certificate
+command_revoke() {
+  init_system
+
+  [[ -n "${CA_REVOKE_CERT}" ]] || _exiterr "Certificate authority doesn't allow certificate revocation."
+
+  cert="${1}"
+  if [[ -L "${cert}" ]]; then
+    # follow symlink and use real certificate name (so we move the real file and not the symlink at the end)
+    local link_target
+    link_target="$(readlink -n "${cert}")"
+    if [[ "${link_target}" =~ ^/ ]]; then
+      cert="${link_target}"
+    else
+      cert="$(dirname "${cert}")/${link_target}"
+    fi
+  fi
+  [[ -f "${cert}" ]] || _exiterr "Could not find certificate ${cert}"
+
+  echo "Revoking ${cert}"
+
+  cert64="$(openssl x509 -in "${cert}" -inform PEM -outform DER | urlbase64)"
+  response="$(signed_request "${CA_REVOKE_CERT}" '{"resource": "revoke-cert", "certificate": "'"${cert64}"'"}' | clean_json)"
+  # if there is a problem with our revoke request _request (via signed_request) will report this and "exit 1" out
+  # so if we are here, it is safe to assume the request was successful
+  echo " + Done."
+  echo " + Renaming certificate to ${cert}-revoked"
+  mv -f "${cert}" "${cert}-revoked"
+}
+
+# Usage: --cleanup (-gc)
+# Description: Move unused certificate files to archive directory
+command_cleanup() {
+  load_config
+
+  # Create global archive directory if not existant
+  if [[ ! -e "${BASEDIR}/archive" ]]; then
+    mkdir "${BASEDIR}/archive"
+  fi
+
+  # Loop over all certificate directories
+  for certdir in "${BASEDIR}/certs/"*; do
+    # Skip if entry is not a folder
+    [[ -d "${certdir}" ]] || continue
+
+    # Get certificate name
+    certname="$(basename "${certdir}")"
+
+    # Create certitifaces archive directory if not existant
+    archivedir="${BASEDIR}/archive/${certname}"
+    if [[ ! -e "${archivedir}" ]]; then
+      mkdir "${archivedir}"
+    fi
+
+    # Loop over file-types (certificates, keys, signing-requests, ...)
+    for filetype in cert.csr cert.pem chain.pem fullchain.pem privkey.pem; do
+      # Skip if symlink is broken
+      [[ -r "${certdir}/${filetype}" ]] || continue
+
+      # Look up current file in use
+      current="$(basename "$(readlink "${certdir}/${filetype}")")"
+
+      # Split filetype into name and extension
+      filebase="$(echo "${filetype}" | cut -d. -f1)"
+      fileext="$(echo "${filetype}" | cut -d. -f2)"
+
+      # Loop over all files of this type
+      for file in "${certdir}/${filebase}-"*".${fileext}"; do
+        # Handle case where no files match the wildcard
+        [[ -f "${file}" ]] || break
+
+        # Check if current file is in use, if unused move to archive directory
+        filename="$(basename "${file}")"
+        if [[ ! "${filename}" = "${current}" ]]; then
+          echo "Moving unused file to archive directory: ${certname}/${filename}"
+          mv "${certdir}/${filename}" "${archivedir}/${filename}"
+        fi
+      done
+    done
+  done
+
+  exit 0
+}
+
+# Usage: --help (-h)
+# Description: Show help text
+command_help() {
+  printf "Usage: %s [-h] [command [argument]] [parameter [argument]] [parameter [argument]] ...\n\n" "${0}"
+  printf "Default command: help\n\n"
+  echo "Commands:"
+  grep -e '^[[:space:]]*# Usage:' -e '^[[:space:]]*# Description:' -e '^command_.*()[[:space:]]*{' "${0}" | while read -r usage; read -r description; read -r command; do
+    if [[ ! "${usage}" =~ Usage ]] || [[ ! "${description}" =~ Description ]] || [[ ! "${command}" =~ ^command_ ]]; then
+      _exiterr "Error generating help text."
+    fi
+    printf " %-32s %s\n" "${usage##"# Usage: "}" "${description##"# Description: "}"
+  done
+  printf -- "\nParameters:\n"
+  grep -E -e '^[[:space:]]*# PARAM_Usage:' -e '^[[:space:]]*# PARAM_Description:' "${0}" | while read -r usage; read -r description; do
+    if [[ ! "${usage}" =~ Usage ]] || [[ ! "${description}" =~ Description ]]; then
+      _exiterr "Error generating help text."
+    fi
+    printf " %-32s %s\n" "${usage##"# PARAM_Usage: "}" "${description##"# PARAM_Description: "}"
+  done
+}
+
+# Usage: --env (-e)
+# Description: Output configuration variables for use in other scripts
+command_env() {
+  echo "# letsencrypt.sh configuration"
+  load_config
+  typeset -p CA LICENSE CHALLENGETYPE HOOK HOOK_CHAIN RENEW_DAYS ACCOUNT_KEY ACCOUNT_KEY_JSON KEYSIZE WELLKNOWN PRIVATE_KEY_RENEW OPENSSL_CNF CONTACT_EMAIL LOCKFILE
+}
+
+# Main method (parses script arguments and calls command_* methods)
+main() {
+  COMMAND=""
+  set_command() {
+    [[ -z "${COMMAND}" ]] || _exiterr "Only one command can be executed at a time. See help (-h) for more information."
+    COMMAND="${1}"
+  }
+
+  check_parameters() {
+    if [[ -z "${1:-}" ]]; then
+      echo "The specified command requires additional parameters. See help:" >&2
+      echo >&2
+      command_help >&2
+      exit 1
+    elif [[ "${1:0:1}" = "-" ]]; then
+      _exiterr "Invalid argument: ${1}"
+    fi
+  }
+
+  [[ -z "${@}" ]] && eval set -- "--help"
+
+  while (( ${#} )); do
+    case "${1}" in
+      --help|-h)
+        command_help
+        exit 0
+        ;;
+
+      --env|-e)
+        set_command env
+        ;;
+
+      --cron|-c)
+        set_command sign_domains
+        ;;
+
+      --signcsr|-s)
+        shift 1
+        set_command sign_csr
+        check_parameters "${1:-}"
+        PARAM_CSR="${1}"
+        ;;
+
+      --revoke|-r)
+        shift 1
+        set_command revoke
+        check_parameters "${1:-}"
+        PARAM_REVOKECERT="${1}"
+        ;;
+
+      --cleanup|-gc)
+        set_command cleanup
+        ;;
+
+      # PARAM_Usage: --domain (-d) domain.tld
+      # PARAM_Description: Use specified domain name(s) instead of domains.txt entry (one certificate!)
+      --domain|-d)
+        shift 1
+        check_parameters "${1:-}"
+        if [[ -z "${PARAM_DOMAIN:-}" ]]; then
+          PARAM_DOMAIN="${1}"
+        else
+          PARAM_DOMAIN="${PARAM_DOMAIN} ${1}"
+         fi
+        ;;
+
+
+      # PARAM_Usage: --force (-x)
+      # PARAM_Description: Force renew of certificate even if it is longer valid than value in RENEW_DAYS
+      --force|-x)
+        PARAM_FORCE="yes"
+        ;;
+
+      # PARAM_Usage: --privkey (-p) path/to/key.pem
+      # PARAM_Description: Use specified private key instead of account key (useful for revocation)
+      --privkey|-p)
+        shift 1
+        check_parameters "${1:-}"
+        PARAM_ACCOUNT_KEY="${1}"
+        ;;
+
+      # PARAM_Usage: --config (-f) path/to/config.sh
+      # PARAM_Description: Use specified config file
+      --config|-f)
+        shift 1
+        check_parameters "${1:-}"
+        CONFIG="${1}"
+        ;;
+
+      # PARAM_Usage: --hook (-k) path/to/hook.sh
+      # PARAM_Description: Use specified script for hooks
+      --hook|-k)
+        shift 1
+        check_parameters "${1:-}"
+        PARAM_HOOK="${1}"
+        ;;
+
+      # PARAM_Usage: --challenge (-t) http-01|dns-01
+      # PARAM_Description: Which challenge should be used? Currently http-01 and dns-01 are supported
+      --challenge|-t)
+        shift 1
+        check_parameters "${1:-}"
+        PARAM_CHALLENGETYPE="${1}"
+        ;;
+
+      # PARAM_Usage: --algo (-a) rsa|prime256v1|secp384r1
+      # PARAM_Description: Which public key algorithm should be used? Supported: rsa, prime256v1 and secp384r1
+      --algo|-a)
+        shift 1
+        check_parameters "${1:-}"
+        PARAM_KEY_ALGO="${1}"
+        ;;
+
+      *)
+        echo "Unknown parameter detected: ${1}" >&2
+        echo >&2
+        command_help >&2
+        exit 1
+        ;;
+    esac
+
+    shift 1
+  done
+
+  case "${COMMAND}" in
+    env) command_env;;
+    sign_domains) command_sign_domains;;
+    sign_csr) command_sign_csr "${PARAM_CSR}";;
+    revoke) command_revoke "${PARAM_REVOKECERT}";;
+    cleanup) command_cleanup;;
+    *) command_help; exit 1;;
+  esac
+}
+
+# Determine OS type
+OSTYPE="$(uname)"
+
+# Check for missing dependencies
+check_dependencies
+
+# Run script
+main "${@:-}"

run.sh

@@ -0,0 +1,16 @@
+#!/usr/bin/env bash
+
+interrupt() {
+  echo
+  echo "Caught ^C, exiting."
+  exit 1
+}
+
+trap interrupt SIGINT
+
+while true; do
+  /letsencrypt.sh --cron --cleanup --hook /dns/hook --challenge dns-01
+  inotifywait --timeout 86400 /letsencrypt/domains.txt
+  sleep 60
+done
+