runit_bootstrap

#!/bin/sh

[ "${DEBUG}" == "yes" ] && set -x

print_log() {
  date_time=$(date '+%Y-%m-%dT%H:%M:%S.%N%:z')
  host_name=$(hostname)
  process_name="runit_bootstrap"
  pid=$$
  message=$1
  
  echo "${date_time} ${host_name} ${process_name}[${pid}]: ${message}"
}

add_config_value() {
  key=${1}
  value=${2}
  config_file=${3:-/etc/postfix/main.cf}
  [ "${key}" = "" ] && echo "ERROR: No key set!" && exit 1
  [ "${value}" = "" ] && echo "WARNING: No value set for key ${key}!"
  property_hits=$(grep -v '^#' "$config_file" | grep -c $key)
  if [ $property_hits -eq 0 ]
  then
	  print_log 'Adding configuration option "'"${key}"'" with value: "'"${value}"'"'
	  echo "${key} = ${value}" >> "$config_file"
  else
	  print_log 'Replacing configuration option "'"${key}"'" with value: "'"${value}"'"'
    sed -i -e "s/^${key}.*/${key} = ${value}/g" "$config_file"
  fi
}

# Required configuration variable(s)
[ -z "${SERVER_HOSTNAME}" ] && echo "ERROR: SERVER_HOSTNAME is not set" && exit 1

# Default configuration variable(s) that can be overwritten
RECIPIENT_LIMIT="${RECIPIENT_LIMIT-1000}"

# Set needed config options in main.cf
add_config_value "inet_protocols" "ipv4"
add_config_value "inet_interfaces" "all"
add_config_value "mynetworks" "0.0.0.0/0"
add_config_value "myhostname" ${SERVER_HOSTNAME}
add_config_value "mydestination" '$myhostname'
add_config_value "myorigin" '$myhostname'
add_config_value "smtpd_recipient_limit" ${RECIPIENT_LIMIT}
add_config_value "smtp_use_tls" "yes"

# Optional: Use a single relay host for all outgoing mail
if [ -n "${SMTP_SERVER}" ]
then
  SMTP_PORT="${SMTP_PORT-25}"
  add_config_value "relayhost" "[${SMTP_SERVER}]:${SMTP_PORT}"

  # Detect SMTPS port 465, and set required parameters accordingly
  if [ "${SMTP_PORT}" = "465" ]
  then
    print_log "Detected SMTPS port 465, setting smtp_tls_wrappermode = yes and smtp_tls_security_level = encrypt."
    add_config_value "smtp_tls_wrappermode" "yes"
    add_config_value "smtp_tls_security_level" "encrypt"
  fi
fi

# Optional: when SMTP_USERNAME and SMTP_PASSWORD are provided, create a sasl_passwd file and add it to the Postfix configuration
if [ -n "${SMTP_USERNAME}" ] && [ -n "${SMTP_PASSWORD}" ]
then
  if [ ! -f /etc/postfix/sasl_passwd ]
  then
    grep -q "${SMTP_SERVER}" /etc/postfix/sasl_passwd  > /dev/null 2>&1
    if [ $? -gt 0 ]
    then
      print_log "Adding SASL authentication configuration."
      echo "[${SMTP_SERVER}]:${SMTP_PORT} ${SMTP_USERNAME}:${SMTP_PASSWORD}" >> /etc/postfix/sasl_passwd
      postmap /etc/postfix/sasl_passwd
    fi
  fi

  add_config_value "smtp_sasl_auth_enable" "yes"
  add_config_value "smtp_sasl_password_maps" "lmdb:/etc/postfix/sasl_passwd"
  add_config_value "smtp_sasl_security_options" "noanonymous"
fi

# Optional: set header tag
if [ -n "${SMTP_HEADER_TAG}" ]
then
  postconf -e "header_checks = regexp:/etc/postfix/header_tag"
  echo -e "/^MIME-Version:/i PREPEND RelayTag: $SMTP_HEADER_TAG\n/^Content-Transfer-Encoding:/i PREPEND RelayTag: $SMTP_HEADER_TAG" > /etc/postfix/header_tag
  print_log "Setting configuration option SMTP_HEADER_TAG with value: ${SMTP_HEADER_TAG}"
fi

# Optional: rewrite outgoing domain in from-addresses
if [ -n "${REWRITE_DOMAIN}" ]
then
  echo -e '/^(.*@).*$/     ${1}'"${REWRITE_DOMAIN}" > /etc/postfix/sender_canonical
  add_config_value "sender_canonical_maps" "regexp:/etc/postfix/sender_canonical"
  print_log "Setting configuration option REWRITE_DOMAIN with value: ${REWRITE_DOMAIN}"
fi

# Optional: rewrite From-headers
if [ -n "${REWRITE_HEADERS}" ]
then
  echo -e "${REWRITE_HEADERS}" > /etc/postfix/header_checks
  add_config_value "smtp_header_checks" "regexp:/etc/postfix/header_checks"
  print_log "Setting configuration option REWRITE_HEADERS with value: ${REWRITE_HEADERS}"
fi

# Optional: DKIM configuration
if [ -n "${DKIM_DOMAIN}" ] && [ -n "${DKIM_KEY}" ] && [ -s "${DKIM_KEY}" ] && [ -n "${DKIM_SELECTOR}" ]
then
  print_log "Enabling OpenDKIM server"
  install -d -o opendkim -g opendkim /run/opendkim
  chown opendkim:opendkim "${DKIM_KEY}"
  chmod 600 "${DKIM_KEY}"
  cat <<EOF > /etc/opendkim/opendkim.conf
BaseDirectory       /run/opendkim
Syslog              yes
SyslogSuccess       yes
Canonicalization    relaxed/simple
Mode                s
Domain              ${DKIM_DOMAIN}
Selector            ${DKIM_SELECTOR}
KeyFile             ${DKIM_KEY}
Socket              inet:8891@localhost
ReportAddress       postmaster@${DKIM_DOMAIN}
SendReports         no
InternalHosts       0.0.0.0/0
DNSTimeout          5
SignatureAlgorithm  rsa-sha256
OversignHeaders     From
UserID              opendkim
EOF
  add_config_value "milter_default_action" "accept"
  add_config_value "milter_protocol" "6"
  add_config_value "smtpd_milters" "inet:localhost:8891"
  add_config_value "non_smtpd_milters" '$smtpd_milters'
fi

# Optional: Use a different queue directory
if [ -n "${QUEUE_DIRECTORY}" ]
then
  add_config_value "queue_directory" "${QUEUE_DIRECTORY}"
fi

# Optional: if a script is set in variable ADDITIONAL_CONFIG, source and execute it
if [ -n "${ADDITIONAL_CONFIG}" ] && [ -s "${ADDITIONAL_CONFIG}" ]
then
  . "${ADDITIONAL_CONFIG}"
fi

# Generate aliases.db
newaliases

# Start postfix
exec /sbin/runsvdir /etc/service