start.sh

#!/bin/sh

set -e

# Set configuration according to ENV
echo 'Settings postfix...'
postconf -e "mydomain = ${RELAY_MYDOMAIN}"
postconf -e "mynetworks = ${RELAY_MYNETWORKS}"
postconf -e "relayhost = ${RELAY_HOST}"
postconf -e "relay_domains = ${RELAY_DOMAINS}"

# Static restrictions for smtp clients
if [ "${RELAY_MODE}" = 'STRICT' ]; then
# set STRICT mode
# no one can send mail to another domain than the relay domains list
# only network/sasl authenticated user can send mail through relay
  postconf -e 'smtpd_relay_restrictions = reject_unauth_destination, permit_sasl_authenticated, permit_mynetworks, reject'
elif [ "${RELAY_MODE}" = 'ALLOW_SASLAUTH_NODOMAIN' ]; then
# set ALLOW_SASLAUTH_NODOMAIN mode
# only authenticated smtp users can send email to another domain than the relay domains list
  postconf -e 'smtpd_relay_restrictions = permit_sasl_authenticated, reject_unauth_destination, permit_mynetworks, reject'
elif [ "${RELAY_MODE}" = 'ALLOW_NETAUTH_NODOMAIN' ]; then
# set ALLOW_NETAUTH_NODOMAIN mode
# only authenticated smtp users can send email to another domain than the relay domains list
  postconf -e 'smtpd_relay_restrictions = permit_mynetworks, reject_unauth_destination, permit_sasl_authenticated, reject'
elif [ "${RELAY_MODE}" = 'ALLOW_AUTH_NODOMAIN' ]; then
# set ALLOW_AUTH_NODOMAIN mode
# no one can send mail to another domain than the relay domains list
# only network/sasl authenticated user can send mail through relay
  postconf -e 'smtpd_relay_restrictions = permit_sasl_authenticated, permit_mynetworks, reject'
else
# set the content of the mode into the restrictions
  postconf -e "smtpd_relay_restrictions = ${RELAY_MODE}"
fi


# Set hostname
if [ -n "${RELAY_MYHOSTNAME}" ]; then
  postconf -e "myhostname = ${RELAY_MYHOSTNAME}"
fi

# Set default postmaster value
if [ -z "$RELAY_POSTMASTER" ]; then
  RELAY_POSTMASTER="postmaster@${RELAY_MYDOMAIN}"
fi
postconf -e "2bounce_notice_recipient = ${RELAY_POSTMASTER}"

# Update the sender mapping databases
if [ -f /etc/postfix/sender_canonical ]; then
  postconf -e "sender_canonical_maps = hash:/etc/postfix/sender_canonical"
  postmap /etc/postfix/sender_canonical
fi

# Update the aliases database
aliases=$(postconf alias_maps |cut -d ':' -f 2)
if [ -f $aliases ]; then
  newaliases
fi

# Configure authentification to relay if needed
if [ -n "${RELAY_LOGIN}" -a -n "${RELAY_PASSWORD}" ]; then
  postconf -e 'smtp_sasl_auth_enable = yes'
  # use password from hash database
  if [ -f /etc/postfix/sasl_passwd ]; then
    postconf -e 'smtp_sasl_password_maps = hash:/etc/postfix/sasl_passwd'
    postmap /etc/postfix/sasl_passwd
  else
   # use static database
    postconf -e "smtp_sasl_password_maps = inline:{${RELAY_HOST}=${RELAY_LOGIN}:${RELAY_PASSWORD}}"
  fi
  postconf -e 'smtp_sasl_security_options = noanonymous'

  if [ -n "${RELAY_USE_TLS}" -a "${RELAY_USE_TLS}" = 'yes' -a -z "${RELAY_TLS_CA}" ]; then
    echo "you must fill RELAY_TLS_CA with the path to the CA file in the container" >&2
    exit 1
  fi
  postconf -e "smtp_tls_CAfile = ${RELAY_TLS_CA}"
  postconf -e "smtp_tls_security_level = ${RELAY_TLS_VERIFY}"
  postconf -e 'smtp_tls_session_cache_database = btree:${data_directory}/smtp_scache'
  postconf -e "smtp_use_tls = ${RELAY_USE_TLS}"
fi

# Restrict sender adresses to only theses of the relay domain
if [ "$RELAY_STRICT_SENDER_MYDOMAIN" = 'true' ]; then
  postconf -e "smtpd_sender_restrictions = check_sender_access inline:{$RELAY_MYDOMAIN=OK}, reject"
fi

# set extras configurations
if [ ! -z "${RELAY_EXTRAS_SETTINGS}" ]; then
  for item in ${RELAY_EXTRAS_SETTINGS}; do
    echo "...set extras setting... ${item}"
    postconf -e "${item}"
  done
fi


echo 'Bulk registering sasl users...'
# Fill the sasl user database with seed
if [ -f /etc/postfix/client_sasl_passwd ]; then
  [ ! -r /etc/postfix/client_sasl_passwd ] && {
	echo "client_sasl_passwd database is not readable" >&2
	exit 1
  }
  for peer in "$(cat /etc/postfix/client_sasl_passwd)"; do
    $user=$(echo "${peer}" | awk '{ print $1 }')
    $pass=$(echo "${peer}" | awk '{ print $2 }')
    echo "${pass}" | /opt/postfix/saslpasswd2.sh -p -u "${RELAY_MYDOMAIN}" -c "${user}"
    echo "...registered user '${user}' into sasl database"
  done
fi

echo 'Starting up...'
exec /usr/bin/supervisord --configuration /etc/supervisord.conf