Script submitted by Almir Duarte Jr. for automating OpenDKIM key generation and configuration for multiple domains.

opendkim_multi_config.sh

#!/bin/bash
# USAGE
# Install opendkim
# List all your domains in file /etc/opendkim/TrustedHosts, one per line
 
CHOWN="$(which chown)"
MKDIR="$(which mkdir)"
REMOVE="$(which rm)"
ECHO="$(which echo)"
COPY="$(which cp)"
MOVE="$(which mv)"
CAT="$(which cat)"
OPENDKIM="$(which opendkim-genkey)"
 
BASE_PATH="/etc/opendkim"
FILE="$BASE_PATH/TrustedHosts"
 
while read -r LINE;
do
        if [[ ! $LINE = \#* ]]; then
                $ECHO "Creating private and public keys for domain $LINE"
                if [ ! -d $BASE_PATH/keys/$LINE ]; then
                        $MKDIR $BASE_PATH/keys/$LINE
                fi
                $OPENDKIM -D $BASE_PATH/keys/$LINE/ -d $LINE -s default
                $CHOWN -R opendkim:opendkim $BASE_PATH/keys/$LINE
                $MOVE $BASE_PATH/keys/$LINE/default.private $BASE_PATH/keys/$LINE/default
 
                NEW_KEY="default._dkim.$LINE $LINE:default:$BASE_PATH/keys/$LINE/default"
                $ECHO "$NEW_KEY" >> $BASE_PATH/KeyTable
 
                NEW_SIGN="*@$LINE default._dkim.$LINE"
                $ECHO "$NEW_SIGN" >> $BASE_PATH/SigningTable
 
                DNS_FILE="/var/named/$LINE.hosts"
                if [ -f $DNS_FILE ]; then
                        DNS_PUBLIC_KEY="$($CAT $BASE_PATH/keys/$LINE/default.txt)"
                        $ECHO $DNS_PUBLIC_KEY >> $DNS_FILE
                fi
        fi
done <$FILE
service named restart
service opendkim restart
postfix reload