EMAIL_USER="xxxxxxx@xxxxxxx.xxx"
EMAIL_PASS="xxxxxxx"
EMAIL_HOST="xxxxxxx.xxx"
EMAIL_DOMAIN="${EMAIL_HOST}"
EMAIL_HOST_PORT="587"
EMAIL_AUTH=$(echo -ne "\0${EMAIL_USER}\0${EMAIL_PASS}" | base64)
EMAIL_FROM="xxxxxxx@xxxxxxx.xxx"
EMAIL_TO="xxxxxxx@xxxxxxx.xxx"
EMAIL_SUBJECT="Test Email From CLI"
EMAIL_DATE=$(date)
EMAIL_BODY=$(cat <<EMAIL_CONTENTS
Hey
This is a test email only

Thanks
EMAIL_CONTENTS
)
SMTP_PAYLOAD=$(cat <<SMTP_COMMANDS
EHLO ${EMAIL_DOMAIN}
AUTH PLAIN ${EMAIL_AUTH}
MAIL FROM: ${EMAIL_FROM}
RCPT TO: ${EMAIL_TO}
DATA
To: ${EMAIL_TO}
From: ${EMAIL_FROM}
Subject: ${EMAIL_SUBJECT}
Date: ${EMAIL_DATE}
${EMAIL_BODY}
.
QUIT
SMTP_COMMANDS
)

echo "${SMTP_PAYLOAD}" | \
    openssl s_client -quiet -starttls smtp -connect ${EMAIL_HOST}:${EMAIL_HOST_PORT}