servnest/fn/dns.php

<?php

function knotcConfExec($cmds) {
	exec(CONF['dns']['knotc_path'] . ' conf-begin', $output['begin'], $code['begin']);
	if ($code['begin'] !== 0)
		output(500, 'knotcConfExec: <code>knotc</code> failed with exit code <samp>' . $code['begin'] . '</samp>: <samp>' . $output['begin'][0] . '</samp>.');

	foreach ($cmds as $cmd) {
		exec(CONF['dns']['knotc_path'] . ' conf-' . $cmd, $output['op'], $code['op']);
		if ($code['op'] !== 0) {
			exec(CONF['dns']['knotc_path'] . ' conf-abort');
			output(500, 'knotcConfExec: <code>knotc</code> failed with exit code <samp>' . $code['op'] . '</samp>: <samp>' . $output['op'][0] . '</samp>.');
		}
	}

	exec(CONF['dns']['knotc_path'] . ' conf-commit', $output['commit'], $code['commit']);
	if ($code['commit'] !== 0) {
		exec(CONF['dns']['knotc_path'] . ' conf-abort');
		output(500, 'knotcConfExec: <code>knotc</code> failed with exit code <samp>' . $code['commit'] . '</samp>: <samp>' . $output['commit'][0] . '</samp>.');
	}
}

function knotcZoneExec($zone, $cmd) {
	$action = checkAction($_POST['action']);

	exec(CONF['dns']['knotc_path'] . ' zone-begin ' . $zone, $output['begin'], $code['begin']);
	if ($code['begin'] !== 0)
		output(500, 'knotcZoneExec: <code>knotc</code> failed with exit code <samp>' . $code['begin'] . '</samp>: <samp>' . $output['begin'][0] . '</samp>.');

	exec(CONF['dns']['knotc_path'] . ' zone-' . $action . 'set ' . $zone . ' ' . implode(' ', $cmd), $output['op'], $code['op']);
	if ($code['op'] !== 0) {
		exec(CONF['dns']['knotc_path'] . ' zone-abort ' . $zone);
		output(500, 'knotcZoneExec: <code>knotc</code> failed with exit code <samp>' . $code['op'] . '</samp>: <samp>' . $output['op'][0] . '</samp>.');
	}

	exec(CONF['dns']['knotc_path'] . ' zone-commit ' . $zone, $output['commit'], $code['commit']);
	if ($code['commit'] !== 0) {
		exec(CONF['dns']['knotc_path'] . ' zone-abort ' . $zone);
		output(500, 'knotcZoneExec: <code>knotc</code> failed with exit code <samp>' . $code['commit'] . '</samp>: <samp>' . $output['commit'][0] . '</samp>.');
	}
}

function checkIpFormat($ip) {
	if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV4))
		return 'A';
	if (filter_var($ip, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6))
		return 'AAAA';
	output(403, 'IP address malformed.');
}

function checkAbsoluteDomainFormat($domain) {
	// If the domain must end with a dot
	if (!filter_var($domain, FILTER_VALIDATE_DOMAIN) OR !preg_match('/^([a-z0-9_-]{1,63}\.){2,127}$/', $domain))
		output(403, 'Domain malformed.');
}

function formatEndWithDot($str) {
	if (!str_ends_with($str, '.'))
		$str .= '.';
	return $str;
}

function formatAbsoluteDomain($domain) {
	$domain = formatEndWithDot(strtolower($domain));
	checkAbsoluteDomainFormat($domain);
	return $domain;
}

function checkAction($action) {
	return match ($action) {
		'add' => '',
		'delete' => 'un',
		default => output(403, 'Wrong value for action.'),
	};
}