diodemail/smtp/parsers.go

/* diodemail - send-only smtp server
 * Copyright (c) 2024 Gnarwhal
 *
 * This file is part of diodemail.
 *
 * diodemail is free software: you can redistribute it and/or modify it under the terms of
 * the GNU General Public License as published by the Free Software Foundation,
 * either version 3 of the License, or (at your option) any later version.
 *
 * diodemail is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along with
 * diodemail. If not, see <https://www.gnu.org/licenses/>.
 */

package smtp

import (
	"fmt"
	"regexp"
)

var ReversePath = regexp.MustCompile(fmt.Sprintf("(?:%v)|<()>", path))
var ForwardPath = regexp.MustCompile(path)
var Domain      = regexp.MustCompile(fmt.Sprintf(".+@(%v)", domain))

// https://datatracker.ietf.org/doc/html/rfc5321#page-41
// Is this...legal, m'lord? (no, but ¯\_(ツ)_/¯)
// ...
// What? You want more? Nope. That is all you get. 
var path        = fmt.Sprintf("<(?:.*:)?(.+@%v)>", domain)
var domain      = fmt.Sprintf("%v(?:.%v)*", sub_domain, sub_domain)
var sub_domain  = fmt.Sprintf("%v(?:%v)?", let_dig, let_str)
var let_str     = fmt.Sprintf("%v*%v", let_dig_und, let_dig)
var let_dig     = fmt.Sprintf("[\\pL\\d]")
var let_dig_und = fmt.Sprintf("[\\pL\\d\\-]")