opendkim.sh

vim scripts/opendkim.sh

#!/bin/bash
# Script Version: 09
# Description: Generate and install OpenDKIM keys for a given domain and append KeyTable + SigningTable entries. Outputs the original generated TXT file directly to stdout and adds DMARC suggestion.

# Set variables
# ========
YEAR=$(date +'%Y')
DOMTLD=$1
KEY_DIR=/etc/opendkim/keys/$DOMTLD
KEYTABLE=/etc/opendkim/KeyTable
SIGNINGTABLE=/etc/opendkim/SigningTable
KEYNAME=${2:-}  # optional explicit key label (defaults to leftmost label of domain)

# Functions
# ========
usage() {
    echo "Usage: $0 <domain.tld> [keylabel]"
    exit 1
}

append_keytable() {
    touch "$KEYTABLE"

    local KEY_LABEL
    if [ -n "$KEYNAME" ]; then
        KEY_LABEL="$KEYNAME"
    else
        KEY_LABEL="${DOMTLD%%.*}"   # leftmost label of domain (e.g., intxtonic for intxtonic.net)
    fi

    local SELECTOR="$YEAR"
    local LINE_DOMAIN_PART="${DOMTLD}:${SELECTOR}:${KEY_DIR}/${SELECTOR}.private"
    local LINE
    LINE=$(printf '%s\t%s' "$KEY_LABEL" "$LINE_DOMAIN_PART")

    if ! grep -Pq "^${KEY_LABEL}\t" "$KEYTABLE" && ! grep -Fq "$LINE_DOMAIN_PART" "$KEYTABLE"; then
        printf '%s\n' "$LINE" >> "$KEYTABLE"
    fi
}

append_signingtable() {
    touch "$SIGNINGTABLE"

    local KEY_LABEL
    if [ -n "$KEYNAME" ]; then
        KEY_LABEL="$KEYNAME"
    else
        KEY_LABEL="${DOMTLD%%.*}"
    fi

    local PATTERN="*@${DOMTLD}"
    local LINE
    LINE=$(printf '%s\t%s' "$PATTERN" "$KEY_LABEL")

    if ! grep -Pq "^\Q${PATTERN}\E\t\Q${KEY_LABEL}\E$" "$SIGNINGTABLE"; then
        sed -i -e "/^\Q${PATTERN}\E\t/d" "$SIGNINGTABLE"
        printf '%s\n' "$LINE" >> "$SIGNINGTABLE"
    fi
}

# Main Process
# ========
[ -z "$DOMTLD" ] && usage

mkdir -p "$KEY_DIR"
cd "$KEY_DIR"

opendkim-genkey -s "$YEAR" -d "$DOMTLD"

chown opendkim:opendkim "${YEAR}.private"
chmod 600 "${YEAR}.private"

append_keytable
append_signingtable

# Output the original generated TXT file to stdout
cat "$KEY_DIR/${YEAR}.txt"

echo  # empty line for readability
echo "; ✅ DMARC (aligns DKIM/SPF)"
echo "_dmarc IN TXT \"v=DMARC1; p=quarantine; rua=mailto:dmarc@bubuit.net\""
echo  # final empty line for readability

systemctl restart opendkim postfix