servnest/pg-act/reg/transfer.php

<?php declare(strict_types=1);

if (preg_match('/' . SUBDOMAIN_REGEX . '/D', $_POST['subdomain']) !== 1)
	output(403, _('This format of subdomain is not allowed.'));

if (array_key_exists($_POST['suffix'], CONF['reg']['suffixes']) !== true)
	output(403, 'This suffix doesn\'t exist.');

$domain = formatAbsoluteDomain($_POST['subdomain'] . '.' . $_POST['suffix']);

if (query('select', 'registry', ['username' => $_SESSION['id'], 'domain' => $domain], ['domain']) !== [])
	output(403, _('The current account already owns this domain.'));

$ns_records = array_column(kdig(name: $domain, type: 'NS', server: CONF['reg']['address'])['authorityRRs'], 'rdataNS');
if (preg_match('/^(?<salt>[0-9a-f]{8})-(?<hash>[0-9a-f]{32})\._transfer-verification\.' . preg_quote(SERVER_NAME, '/') . '\.$/Dm', implode(LF, $ns_records), $matches) !== 1)
	output(403, _('NS authentication record not found.'));

checkAuthToken($matches['salt'], $matches['hash']);

rateLimit();

DB->prepare('UPDATE registry SET username = :username WHERE domain = :domain')
->execute([':username' => $_SESSION['id'], ':domain' => $domain]);

knotcZoneExec($_POST['suffix'], [
	$domain,
	'NS',
	$matches['salt'] . '-' . $matches['hash'] . '._transfer-verification.' . SERVER_NAME . '.'
], 'delete');

output(200, _('The domain has been transferred to the current account ; the NS authentication record has been automatically deleted.'));