diff --git a/helpers/create_client_whitelist.sh b/helpers/create_client_whitelist.sh
new file mode 100755
index 0000000..ef1e3a7
--- /dev/null
+++ b/helpers/create_client_whitelist.sh
@@ -0,0 +1,85 @@
+#!/usr/bin/env bash
+
+tmp_err_msg=$(mktemp)
+
+# -------------
+# --- Some functions
+# -------------
+clean_up() {
+
+   # Perform program exit housekeeping
+   rm -f $tmp_err_msg
+   exit $1
+}
+
+echononl(){
+   echo X\\c > /tmp/shprompt$$
+   if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
+      echo -e -n "$*\\c" 1>&2
+   else
+       echo -e -n "$*" 1>&2
+   fi
+   rm /tmp/shprompt$$
+}
+
+fatal(){
+   echo ""
+   echo -e "fatal error: $*"
+   echo ""
+   echo -e "\t\033[31m\033[1mInstalllation will be interrupted\033[m\033[m"
+   echo ""
+   exit 1
+}
+
+error(){
+   echo ""
+   echo -e "\t[ \033[31m\033[1mFehler\033[m ]: $*"
+   echo ""
+}
+
+warn (){
+   echo ""
+   echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
+   echo ""
+}
+
+info (){
+   echo ""
+   echo -e "\t[ \033[32m\033[1mInfo\033[m ]: $*"
+   echo ""
+}
+
+echo_done() {
+   echo -e "\033[80G[ \033[32mdone\033[m ]"
+}
+echo_ok() {
+   echo -e "\033[80G[ \033[32mok\033[m ]"
+}
+echo_warning() {
+   echo -e "\033[80G[ \033[33m\033[1mwarn\033[m ]"
+}
+echo_failed(){
+   echo -e "\033[80G[ \033[1;31mfailed\033[m ]"
+}
+echo_skipped() {
+   echo -e "\033[80G[ \033[33m\033[1mskipped\033[m ]"
+}
+
+echononl "   Create file \"client_whitelist\""
+if [[ ! -f "/etc/postfix/client_whitelist" ]]; then
+   cat <<EOF > /etc/postfix/client_whitelist
+# onion - tor hidden service
+127.0.0.25        OK
+EOF
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+      postmap btree:/etc/postfix/client_whitelist
+   else
+      echo_failed
+   fi
+else
+   echo_skipped
+fi
+
+
+clean_up 0
diff --git a/helpers/create_greylist_client_access_pcre.sh b/helpers/create_greylist_client_access_pcre.sh
new file mode 100755
index 0000000..d10ad39
--- /dev/null
+++ b/helpers/create_greylist_client_access_pcre.sh
@@ -0,0 +1,122 @@
+#!/usr/bin/env bash
+
+tmp_err_msg=$(mktemp)
+
+# -------------
+# --- Some functions
+# -------------
+clean_up() {
+
+   # Perform program exit housekeeping
+   rm -f $tmp_err_msg
+   exit $1
+}
+
+echononl(){
+   echo X\\c > /tmp/shprompt$$
+   if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
+      echo -e -n "$*\\c" 1>&2
+   else
+       echo -e -n "$*" 1>&2
+   fi
+   rm /tmp/shprompt$$
+}
+
+fatal(){
+   echo ""
+   echo -e "fatal error: $*"
+   echo ""
+   echo -e "\t\033[31m\033[1mInstalllation will be interrupted\033[m\033[m"
+   echo ""
+   exit 1
+}
+
+error(){
+   echo ""
+   echo -e "\t[ \033[31m\033[1mFehler\033[m ]: $*"
+   echo ""
+}
+
+warn (){
+   echo ""
+   echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
+   echo ""
+}
+
+info (){
+   echo ""
+   echo -e "\t[ \033[32m\033[1mInfo\033[m ]: $*"
+   echo ""
+}
+
+echo_done() {
+   echo -e "\033[80G[ \033[32mdone\033[m ]"
+}
+echo_ok() {
+   echo -e "\033[80G[ \033[32mok\033[m ]"
+}
+echo_warning() {
+   echo -e "\033[80G[ \033[33m\033[1mwarn\033[m ]"
+}
+echo_failed(){
+   echo -e "\033[80G[ \033[1;31mfailed\033[m ]"
+}
+echo_skipped() {
+   echo -e "\033[80G[ \033[33m\033[1mskipped\033[m ]"
+}
+
+echononl "   Create file \"greylist_client_access_pcre\""
+if [[ ! -f /etc/postfix/greylist_client_access_pcre ]]; then
+   cat <<EOF > /etc/postfix/greylist_client_access_pcre
+# ---
+# Check Client Access for greylisting (selective greylisting)
+# ---
+#
+# - Note:
+# -
+# -    Action 'check_greylist' must be defined by 'smtpd_restriction_classes' 
+# -    and also set with an action (check_policy_service inet:127.0.0.1:10023) 
+# -    in file /etc/postfix/ main.cf.
+# -
+# -    Your main.cf may looks like:
+# -
+# -       smtpd_restriction_classes = check_greylist
+# -       check_greylist = check_policy_service inet:127.0.0.1:10023
+# -
+# -       smtpd_recipient_restrictions =
+# -          ...
+# -          check_client_access pcre:/etc/postfix/greylist_client_access_pcre,
+# -          ...
+# -
+# -       smtpd_relay_restrictions =
+# -          ...
+# -          check_client_access pcre:/etc/postfix/greylist_client_access_pcre,
+# -          ...
+
+# ---
+# - For clients matching the following rules greylisting check is applied.
+# ---
+
+# unkown clients
+/^unknown$/    check_greylist
+
+# everything with 3 or more hyphens in the hostname
+/(\\-.+){3}$/   check_greylist
+# everything with 4 or more dots in the hostname
+/(\\..+){4}$/   check_greylist
+
+# dialups
+/(^|[0-9.x_-])(abo|br(e|oa)dband|cabel|(hk)?cablep?|catv|cbl|cidr|d?client2?|cust(omer)?s?|dhcp|dial?(in|up)?|d[iu]p|[asx]?dsld?|dyn(a(dsl|mic)?)?|home|in-addr|modem(cable)?|(di)?pool|ppp|ptr|rev|static|user|YahooBB[0-9]{12}|c[[:alnum:]]{6,}(\\.[a-z]{3})?\\.virtua|[1-9]Cust[0-9]+|AC[A-Z][0-9A-F]{5}\\.ipt|pcp[0-9]{6,}pcs|S0106[[:alnum:]]{12,}\\.[a-z]{2})[0-9.x_-]/  check_greylist
+
+EOF
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+   else
+      echo_failed
+   fi
+else
+   echo_skipped
+fi
+
+
+clean_up 0
diff --git a/helpers/create_header_checks_pcre.sh b/helpers/create_header_checks_pcre.sh
new file mode 100755
index 0000000..35580af
--- /dev/null
+++ b/helpers/create_header_checks_pcre.sh
@@ -0,0 +1,97 @@
+#!/usr/bin/env bash
+
+tmp_err_msg=$(mktemp)
+
+# -------------
+# --- Some functions
+# -------------
+clean_up() {
+
+   # Perform program exit housekeeping
+   rm -f $tmp_err_msg
+   exit $1
+}
+
+echononl(){
+   echo X\\c > /tmp/shprompt$$
+   if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
+      echo -e -n "$*\\c" 1>&2
+   else
+       echo -e -n "$*" 1>&2
+   fi
+   rm /tmp/shprompt$$
+}
+
+fatal(){
+   echo ""
+   echo -e "fatal error: $*"
+   echo ""
+   echo -e "\t\033[31m\033[1mInstalllation will be interrupted\033[m\033[m"
+   echo ""
+   exit 1
+}
+
+error(){
+   echo ""
+   echo -e "\t[ \033[31m\033[1mFehler\033[m ]: $*"
+   echo ""
+}
+
+warn (){
+   echo ""
+   echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
+   echo ""
+}
+
+info (){
+   echo ""
+   echo -e "\t[ \033[32m\033[1mInfo\033[m ]: $*"
+   echo ""
+}
+
+echo_done() {
+   echo -e "\033[80G[ \033[32mdone\033[m ]"
+}
+echo_ok() {
+   echo -e "\033[80G[ \033[32mok\033[m ]"
+}
+echo_warning() {
+   echo -e "\033[80G[ \033[33m\033[1mwarn\033[m ]"
+}
+echo_failed(){
+   echo -e "\033[80G[ \033[1;31mfailed\033[m ]"
+}
+echo_skipped() {
+   echo -e "\033[80G[ \033[33m\033[1mskipped\033[m ]"
+}
+
+echononl "   Create file \"header_checks_pcre\""
+if [[ ! -f "/etc/postfix//header_checks_pcre" ]]; then
+   cat <<EOF > /etc/postfix//header_checks_pcre
+# ---
+# - Replace headers
+# ---
+
+# - Replace recieved from
+/^Received: from (.* \\([-._[:alnum:]]+ \\[[.[:digit:]]{7,15}\\]\\)).*?([[:space:]]+).*\\(Authenticated sender: ([^)]+)\\)(.*)/ REPLACE Received: from [127.0.0.1] (localhost [127.0.0.1])\$2(Authenticated sender: \$3)\$4
+
+# ---
+# - Ignore Headers
+# ---
+
+/^\s*User-Agent/        IGNORE
+/^\s*X-Enigmail/        IGNORE
+/^\s*X-Mailer/          IGNORE
+/^\s*X-Originating-IP/  IGNORE
+EOF
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+   else
+      echo_failed
+   fi
+else
+   echo_skipped
+fi
+
+
+clean_up 0
diff --git a/install_postfwd.sh b/install_postfwd.sh
new file mode 100755
index 0000000..ee4d5f3
--- /dev/null
+++ b/install_postfwd.sh
@@ -0,0 +1,261 @@
+#!/usr/bin/env bash
+
+tmp_err_msg=$(mktemp)
+
+# -------------
+# --- Some functions
+# -------------
+clean_up() {
+
+   # Perform program exit housekeeping
+   rm -f $tmp_err_msg
+   exit $1
+}
+
+echononl(){
+   echo X\\c > /tmp/shprompt$$
+   if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
+      echo -e -n "$*\\c" 1>&2
+   else
+       echo -e -n "$*" 1>&2
+   fi
+   rm /tmp/shprompt$$
+}
+
+fatal(){
+   echo ""
+   echo -e "fatal error: $*"
+   echo ""
+   echo -e "\t\033[31m\033[1mInstalllation will be interrupted\033[m\033[m"
+   echo ""
+   exit 1
+}
+
+error(){
+   echo ""
+   echo -e "\t[ \033[31m\033[1mFehler\033[m ]: $*"
+   echo ""
+}
+
+warn (){
+   echo ""
+   echo -e "\t[ \033[33m\033[1mWarning\033[m ]: $*"
+   echo ""
+}
+
+info (){
+   echo ""
+   echo -e "\t[ \033[32m\033[1mInfo\033[m ]: $*"
+   echo ""
+}
+
+echo_done() {
+   echo -e "\033[80G[ \033[32mdone\033[m ]"
+}
+echo_ok() {
+   echo -e "\033[80G[ \033[32mok\033[m ]"
+}
+echo_warning() {
+   echo -e "\033[80G[ \033[33m\033[1mwarn\033[m ]"
+}
+echo_failed(){
+   echo -e "\033[80G[ \033[1;31mfailed\033[m ]"
+}
+echo_skipped() {
+   echo -e "\033[80G[ \033[33m\033[1mskipped\033[m ]"
+}
+
+## - Install Postfix Firewall Daemon from debian packages system
+## -
+echononl "   Install Postfix Firewall Daemon from debian packages system"
+_pkg="postfwd"
+if aptitude search $_pkg | grep " $_pkg " | grep -e "^i" > /dev/null 2>&1 ; then
+   echo_skipped
+else
+   DEBIAN_FRONTEND=noninteractive apt-get -y install $_pkg > /dev/null 2> $tmp_err_msg
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+   else
+      echo_failed
+      error "$(cat $tmp_err_msg)"
+   fi
+fi
+
+echononl "   Adjust /etc/default/postfwd"
+perl -i -n -p -e "s#^(\s*)(STARTUP=.*)#\#\1\2\nSTARTUP=1#" \
+   /etc/default/postfwd > $tmp_err_msg 2>&1
+if [[ $? -eq 0 ]] ; then
+   echo_ok
+else
+   echo_failed
+   error "$(cat $tmp_err_msg)"
+fi
+
+_file="/etc/postfix/postfwd.wl-user"
+echononl "   Create whitelist file '$_file' for postfwd"
+if [[ ! -f "$_file" ]]; then
+	cat << EOF > "$_file"
+# ---
+# SASL Users whitelisted by postfwd
+# ---
+
+EOF
+	if [[ $? -eq 0 ]] ; then
+		echo_ok
+	else
+		echo_failed
+	fi
+else
+	echo_skipped
+fi
+
+_file="/etc/postfix/postfwd.bl-user"
+echononl "   Create whitelist file '$_file' for postfwd"
+if [[ ! -f "$_file" ]]; then
+	cat << EOF > "$_file"
+# ---
+# SASL Users blocked by postfwd
+# ---
+
+EOF
+	if [[ $? -eq 0 ]] ; then
+		echo_ok
+	else
+		echo_failed
+	fi
+else
+	echo_skipped
+fi
+
+_file="/etc/postfix/postfwd.bl-sender"
+echononl "   Create whitelist file '$_file' for postfwd"
+if [[ ! -f "$_file" ]]; then
+	cat << EOF > "$_file"
+# ---
+# Sender addresses blocked by postfwd
+# ---
+
+EOF
+	if [[ $? -eq 0 ]] ; then
+		echo_ok
+	else
+		echo_failed
+	fi
+else
+	echo_skipped
+fi
+
+echononl "   Create configuration file '/etc/postfix/postfwd.cf'.."
+if [[ ! -f "/etc/postfix/postfwd.cf" ]]; then
+	cat << EOF > /etc/postfix/postfwd.cf
+
+#======= Definitions ============
+
+# Match messages with an associated SASL username
+&&SASL_AUTH {
+    sasl_username!~^\$
+}
+
+# Whitelist users
+&&TRUSTED_USERS {
+    sasl_username==file:/etc/postfix/postfwd.wl-user
+}
+
+# Blacklist users
+&&BLOCK_USERS {
+   sasl_username==file:/etc/postfix/postfwd.bl-user
+}
+
+# Blacklist sender adresses
+&&BLOCK_SENDER {
+   sender==file:/etc/postfix/postfwd.bl-sender
+}
+
+# Inbound emails only
+&&INCOMING {
+    client_address!=127.0.0.1
+}
+
+
+#======= Rule Sets ============
+
+# Whitelists
+
+# Whitelist sasl users
+id=WHL_USERS
+	&&TRUSTED_USERS
+	action=DUNNO
+
+
+# Blacklist users
+
+id=BL_USERS
+   &&BLOCK_USERS
+   action=REJECT User is blocked by so36.NET admins. Error: BL_USERS
+
+# Blacklist sender
+#
+#    Claim successful delivery and silently discard the message.
+#
+id=BL_SENDER
+   &&BLOCK_SENDER
+   action=DISCARD
+   #action=REJECT Sender address is blocked by so36.NET admins. Error: BL_SENDER
+
+
+# Rate Limits
+
+# Block messages with more than 50 recipients
+id=BLOCK_MSG_RCPT
+    &&INCOMING
+    &&SASL_AUTH
+	 recipient_count=50
+    action=REJECT Too many recipients, please reduce to less than 50 or consider using a mailing list. Error: BLOCK_MSG_RCPT
+
+# Block users sending more than 50 messages/hour
+id=RATE_MSG
+    &&INCOMING
+    &&SASL_AUTH
+    action=rate(\$\$sasl_username/50/3600/450 4.7.1 Number messages per hour exceeded. Error:RATE_MSG)
+
+# Block users sending more than 250 recipients total/hour
+id=RATE_RCPT
+    &&INCOMING
+    &&SASL_AUTH
+    action=rcpt(\$\$sasl_username/250/3600/450 4.7.1 Number recipients per hour exceeded. Error:RATE_RCPT)
+
+EOF
+	if [[ $? -eq 0 ]] ; then
+		echo_ok
+	else
+		echo_failed
+	fi
+else
+	echo_skipped
+fi
+
+echononl "   Restart Postfix firewall daemon 'postfwd'.."
+if $systemd_exists ; then
+   systemctl restart postfwd > /dev/null 2> $tmp_err_msg
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+   else
+      echo_failed
+      error "$(cat $tmp_err_msg)"
+   fi
+else
+   /etc/init.d/postfwd restart > /dev/null 2> $tmp_err_msg
+   if [[ $? -eq 0 ]] ; then
+      echo_ok
+   else
+      echo_failed
+      error "$(cat $tmp_err_msg)"
+   fi
+fi
+
+
+warn "OpenDKIM is installed, bur not integrated in postfix mailsystem (/etc/postfix/main.cf"
+
+
+
+clean_up 0