Dockerfile

@@ -1,5 +1,5 @@
 #
-# simple postfix smtp relay
+# simple postfix smarthost smtp relay
 #
 
 FROM alpine:3.13
@@ -9,13 +9,13 @@ LABEL author="Asif Bacchus <asif@bacchus.cloud>"
 LABEL maintainer="Asif Bacchus <asif@bacchus.cloud>"
 LABEL org.label-schema.schema-version="1.0"
 LABEL org.label-schema.docker.cmd=""
-LABEL org.label-schema.description="Simple postfix smtp mail relay on Alpine."
+LABEL org.label-schema.description="Simple postfix smarthost smtp mail relay on Alpine Linux."
-LABEL org.label-schema.url="https://git.asifbacchus.app/ab-docker/postfix-smtp-relay"
+LABEL org.label-schema.url=""
-LABEL org.label-schema.usage="https://git.asifbacchus.app/ab-docker/postfix-smtp-relay"
+LABEL org.label-schema.usage=""
-LABEL org.label-schema.vcs-url="https://git.asifbacchus.app/ab-docker/postfix-smtp-relay.git"
+LABEL org.label-schema.vcs-url=""
 
-# install packages and clean-up
+# install mSMTP
-RUN apk --no-cache add \
+RUN apk --no-cache \
     ca-certificates \
     postfix \
     bind-tools \
@@ -23,8 +23,8 @@ RUN apk --no-cache add \
 
 # set environment variables
 ENV TZ=Etc/UTC
-ENV LOCAL_HOSTNAME=""
+ENV LOCAL_HOSTNAME=${HOSTNAME}
-ENV LOCAL_DOMAINNAME=""
+ENV LOCAL_DOMAINNAME=${HOSTNAME#*.}
 ENV LOCAL_ENCRYPTION=false
 ENV SMARTHOST=""
 ENV SMARTHOST_PORT=587
@@ -41,8 +41,8 @@ ENTRYPOINT [ "/usr/local/bin/entrypoint.sh" ]
 CMD [ "/usr/local/sbin/postfix", "start-fg" ]
 
 # set parameters, vendor, version and build-date labels
-LABEL org.label-schema.docker.params="TZ=Etc/UTC, HOSTNAME=(container hostname), DOMAINNAME=(derived from hostname), LOCAL_ENCRYPTION=false|optional|true, SMARTHOST=..., SMARTHOST_PORT=587, SMARTHOST_USERNAME=..., SMARTHOST_PASSWORD=..., SMARTHOST_ENCRYPTION=optional|false|true"
+LABEL org.label-schema.docker.params="TZ=Etc/UTC, HOSTNAME=HOSTNAME, DOMAINNAME=(derived from hostname), LOCAL_ENCRYPTION=false, SMARTHOST, SMARTHOST_PORT=587, SMARTHOST_USERNAME, SMARTHOST_PASSWORD, SMARTHOST_ENCRYPTION='OPTIONAL'"
 LABEL org.label-schema.vendor="Alpine 3.13, Postfix 3.5.10-r0"
-LABEL org.label-schema.version="0.5"
+LABEL org.label-schema.version="0.1"
 ARG BUILD_DATE
 LABEL org.label-schema.build-date=${BUILD_DATE}

entrypoint.sh

@@ -8,33 +8,23 @@ convertCase () {
     printf "%s" "$1" | tr "[:lower:]" "[:upper:]"
 }
 
-if [ -f "/etc/postfix/main.cf.override" ]; then
-    # use provided configuration file
-    printf "\nAppending provided MAIN configuration... "
-    cat /etc/postfix/main.cf.override >> /etc/postfix/main.cf
-    \rm -f /tmp/main.cf.insert
-else
-    # process auto-setup
 printf "\nVerifying environment variables... "
 
 # check for missing environment variable values
 if [ -z "$SMARTHOST" ]; then
     printf "\nYou must specify the hostname or IP address of a smarthost where mail should be relayed.\n\n"
-        exit 1
 fi
 if [ -z "$SMARTHOST_USERNAME" ]; then
     printf "\nYou must provide a username for smarthost authentication.\n\n"
-        exit 1
 fi
 if [ -z "$SMARTHOST_PASSWORD" ]; then
     printf "\nYou must provide a password for smarthost authentication.\n\n"
-        exit 1
 fi
 
 # set failsafes
 [ -z "$SMARTHOST_PORT" ] && SMARTHOST_PORT=587
-    [ -z "$LOCAL_HOSTNAME" ] && LOCAL_HOSTNAME="$(uname -n)"
+[ -z "$LOCAL_HOSTNAME" ] && LOCAL_HOSTNAME="smarthost"
-    [ -z "$LOCAL_DOMAINNAME" ] && LOCAL_DOMAINNAME="${LOCAL_HOSTNAME#*.}"
+[ -z "$LOCAL_DOMAINNAME" ] && LOCAL_DOMAINNAME="smarthost"
 
 printf "done\n"
 printf "updating configuration files... "
@@ -75,22 +65,13 @@ else
         ;;
 esac
 
-    # append configuration and remove temp file
 cat /tmp/main.cf.insert >> /etc/postfix/main.cf
-    \rm -f /tmp/main.cf.insert
+rm -f /tmp/main.cf.insert
-fi
-printf "done\n"
 
-if [ -f "/etc/postfix/master.cf.override" ]; then
-    # use provided configuration file
-    printf "\nUsing provided MASTER configuration... "
-    \cp --force /etc/postfix/master.cf.override /etc/postfix/master.cf
-else
 # update master.cf
 sed -i 's/#tlsproxy/tlsproxy/' /etc/postfix/master.cf
-fi
-printf "done\n"
 
+printf "done\n"
 printf "container setup complete!\n"
 
 # run CMD passed to this container

main.cf.insert

@@ -13,7 +13,7 @@ relayhost = [{SMARTHOST}]:{SMARTHOST_PORT}
 
 #smtpd_tls_chain_files = /certs/privkey.pem, /certs/fullchain.pem
 #smtpd_tls_mandatory_ciphers = high
-#smtpd_tls_mandatory_exclude_ciphers = aNULL, MD5
+#smptd_tls_mandatory_exclude_ciphers = aNULL, MD5
 #smtpd_tls_mandatory_protocols = >=TLSv1.2
 #smtpd_tls_security_level = {LOCAL_ENCRYPTION}