validate_domain.inc.php

<?php

/*
Copyright (c) 2007, Till Brehm, projektfarm Gmbh
Copyright (c) 2012, Marius Cramer, pixcept KG
All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice,
      this list of conditions and the following disclaimer.
    * Redistributions in binary form must reproduce the above copyright notice,
      this list of conditions and the following disclaimer in the documentation
      and/or other materials provided with the distribution.
    * Neither the name of ISPConfig nor the names of its contributors
      may be used to endorse or promote products derived from this software without
      specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

class validate_domain {

	function get_error($errmsg) {
		global $app;

		if(isset($app->tform->wordbook[$errmsg])) {
			return $app->tform->wordbook[$errmsg]."<br>\r\n";
		} else {
			return $errmsg."<br>\r\n";
		}
	}

	/* Validator function for domain (website) */
	function web_domain($field_name, $field_value, $validator) {
		if(empty($field_value)) return $this->get_error('domain_error_empty');

		// do not allow wildcards on website domains
		$result = $this->_regex_validate($field_value);
		if(!$result) return $this->get_error('domain_error_regex');

		$result = $this->_check_unique($field_value);
		if(!$result) return $this->get_error('domain_error_unique');

		$pattern = '/\.acme\.invalid$/';
		if(preg_match($pattern, $field_value)) return $this->get_error('domain_error_acme_invalid');
	}

	/* Validator function for sub domain */
	function sub_domain($field_name, $field_value, $validator) {
		if(empty($field_value)) return $this->get_error('domain_error_empty');

		$allow_wildcard = $this->_wildcard_limit();
		if($allow_wildcard == false && substr($field_value, 0, 2) === '*.') return $this->get_error('domain_error_wildcard');

		$result = $this->_regex_validate($field_value, $allow_wildcard);
		if(!$result) return $this->get_error('domain_error_regex');

		$result = $this->_check_unique($field_value);
		if(!$result) return $this->get_error('domain_error_unique');

		$pattern = '/\.acme\.invalid$/';
		if(preg_match($pattern, $field_value)) return $this->get_error('domain_error_acme_invalid');
	}

	/* Validator function for alias domain */
	function alias_domain($field_name, $field_value, $validator) {
		if(empty($field_value)) return $this->get_error('domain_error_empty');

		// do not allow wildcards on alias domains
		$result = $this->_regex_validate($field_value);
		if(!$result) return $this->get_error('domain_error_regex');

		$result = $this->_check_unique($field_value);
		if(!$result) return $this->get_error('domain_error_unique');

		$pattern = '/\.acme\.invalid$/';
		if(preg_match($pattern, $field_value)) return $this->get_error('domain_error_acme_invalid');
	}

	/* Validator function for checking the auto subdomain of a web/aliasdomain */
	function web_domain_autosub($field_name, $field_value, $validator) {
		global $app;
		if(empty($field_value) || $field_name != 'subdomain') return; // none set

		if(isset($app->remoting_lib->primary_id)) {
			$check_domain = $app->remoting_lib->dataRecord['domain'];
		} else {
			$check_domain = $_POST['domain'];
		}

		$app->uses('ini_parser,getconf');
		$settings = $app->getconf->get_global_config('domains');
		if ($settings['use_domain_module'] == 'y') {
			$sql = "SELECT domain_id, domain FROM domain WHERE domain_id = ?";
			$domain_check = $app->db->queryOneRecord($sql, $check_domain);
			if(!$domain_check) return;
			$check_domain = $domain_check['domain'];
		}

		$result = $this->_check_unique($field_value . '.' . $check_domain, true);
		if(!$result) return $this->get_error('domain_error_autosub');
	}

	/* Check apache directives */
	function web_apache_directives($field_name, $field_value, $validator) {
		global $app;

		if(trim($field_value) != '') {
			$security_config = $app->getconf->get_security_config('ids');

			if($security_config['apache_directives_scan_enabled'] == 'yes') {

				// Get blacklist
				$blacklist_path = '/usr/local/ispconfig/security/apache_directives.blacklist';
				if(is_file('/usr/local/ispconfig/security/apache_directives.blacklist.custom')) $blacklist_path = '/usr/local/ispconfig/security/apache_directives.blacklist.custom';
				if(!is_file($blacklist_path)) $blacklist_path = realpath(ISPC_ROOT_PATH.'/../security/apache_directives.blacklist');

				$directives = explode("\n",$field_value);
				$regex = explode("\n",file_get_contents($blacklist_path));
				$blocked = false;
				$blocked_line = '';

				if(is_array($directives) && is_array($regex)) {
					foreach($directives as $directive) {
						$directive = trim($directive);
						foreach($regex as $r) {
							if(trim($r) == '') {
								continue;
							}
							if(preg_match(trim($r),$directive)) {
								$blocked = true;
								$blocked_line .= $directive.'<br />';
							};
						}
					}
				}
			}
		}

		if($blocked === true) {
			return $this->get_error('apache_directive_blocked_error').' '.$blocked_line;
		}
	}

	/* Check nginx directives */
	function web_nginx_directives($field_name, $field_value, $validator) {
		global $app;

		if(trim($field_value) != '') {
			$security_config = $app->getconf->get_security_config('ids');

			if($security_config['nginx_directives_scan_enabled'] == 'yes') {

				// Get blacklist
				$blacklist_path = '/usr/local/ispconfig/security/nginx_directives.blacklist';
				if(is_file('/usr/local/ispconfig/security/nginx_directives.blacklist.custom')) $blacklist_path = '/usr/local/ispconfig/security/nginx_directives.blacklist.custom';
				if(!is_file($blacklist_path)) $blacklist_path = realpath(ISPC_ROOT_PATH.'/../security/nginx_directives.blacklist');

				$directives = explode("\n",$field_value);
				$regex = explode("\n",file_get_contents($blacklist_path));
				$blocked = false;
				$blocked_line = '';

				if(is_array($directives) && is_array($regex)) {
					foreach($directives as $directive) {
						$directive = trim($directive);
						foreach($regex as $r) {
							if(preg_match(trim($r),$directive)) {
								$blocked = true;
								$blocked_line .= $directive.'<br />';
							};
						}
					}
				}
			}
		}

		if($blocked === true) {
			return $this->get_error('nginx_directive_blocked_error').' '.$blocked_line;
		}
	}


	/* internal validator function to match regexp */
	function _regex_validate($domain_name, $allow_wildcard = false) {
		$pattern = '/^' . ($allow_wildcard == true ? '(\*\.)?' : '') . '[\w\.\-]{1,255}\.[a-zA-Z0-9\-]{2,63}$/';
		return preg_match($pattern, $domain_name);
	}

	/* check if the domain hostname is unique (keep in mind the auto subdomains!) */
	function _check_unique($domain_name, $only_domain = false) {
		global $app, $page;

		if(isset($app->remoting_lib->primary_id)) {
			$primary_id = $app->remoting_lib->primary_id;
			$domain = $app->remoting_lib->dataRecord;
		} else {
			$primary_id = $app->tform->primary_id;
			$domain = $page->dataRecord;
		}

		if($domain['ip_address'] == '' || $domain['ipv6_address'] == ''){
			if($domain['parent_domain_id'] > 0){
				$parent_domain = $app->db->queryOneRecord("SELECT * FROM web_domain WHERE domain_id = ?", $domain['parent_domain_id']);
				if(is_array($parent_domain) && !empty($parent_domain)){
					$domain['ip_address'] = $parent_domain['ip_address'];
					$domain['ipv6_address'] = $parent_domain['ipv6_address'];
				}
			}
		}

		// check if domain has alias/subdomains - if we move a web to another IP, make sure alias/subdomains are checked as well
		$aliassubdomains = $app->db->queryAllRecords("SELECT * FROM web_domain WHERE parent_domain_id = ? AND (type = 'alias' OR type = 'subdomain' OR type = 'vhostsubdomain')", $primary_id);
		$additional_sql1 = '';
		$additional_sql2 = '';
		$domain_params = array();
		if(is_array($aliassubdomains) && !empty($aliassubdomains)){
			foreach($aliassubdomains as $aliassubdomain){
				$additional_sql1 .= " OR d.domain = ?";
				$additional_sql2 .= " OR CONCAT(d.subdomain, '.', d.domain) = ?";
				$domain_params[] = $aliassubdomain['domain'];
			}
		}


		$qrystr = "SELECT d.domain_id, IF(d.parent_domain_id != 0 AND p.domain_id IS NOT NULL, p.ip_address, d.ip_address) as `ip_address`, IF(d.parent_domain_id != 0 AND p.domain_id IS NOT NULL, p.ipv6_address, d.ipv6_address) as `ipv6_address` FROM `web_domain` as d LEFT JOIN `web_domain` as p ON (p.domain_id = d.parent_domain_id) WHERE (d.domain = ?" . $additional_sql1 . ") AND d.server_id = ? AND d.domain_id != ?" . ($primary_id ? " AND d.parent_domain_id != ?" : "");
		$params = array_merge(array($domain_name), $domain_params, array($domain['server_id'], $primary_id, $primary_id));
		$checks = $app->db->queryAllRecords($qrystr, true, $params);
		if(is_array($checks) && !empty($checks)){
			foreach($checks as $check){
				if($domain['ip_address'] == '*') return false;
				if($check['ip_address'] == '*') return false;
				if($domain['ip_address'] != '' && $check['ip_address'] == $domain['ip_address']) return false;
				if($domain['ipv6_address'] != '' && $check['ipv6_address'] == $domain['ipv6_address']) return false;
			}
		}

		if($only_domain == false) {
			$qrystr = "SELECT d.domain_id, IF(d.parent_domain_id != 0 AND p.domain_id IS NOT NULL, p.ip_address, d.ip_address) as `ip_address`, IF(d.parent_domain_id != 0 AND p.domain_id IS NOT NULL, p.ipv6_address, d.ipv6_address) as `ipv6_address` FROM `web_domain` as d LEFT JOIN `web_domain` as p ON (p.domain_id = d.parent_domain_id) WHERE (CONCAT(d.subdomain, '.', d.domain) = ?" . $additional_sql2 . ") AND d.server_id = ? AND d.domain_id != ?" . ($primary_id ? " AND d.parent_domain_id != ?" : "");
			$params = array_merge(array($domain_name), $domain_params, array($domain['server_id'], $primary_id, $primary_id));
			$checks = $app->db->queryAllRecords($qrystr, true, $params);
			if(is_array($checks) && !empty($checks)){
				foreach($checks as $check){
					if($domain['ip_address'] == '*') return false;
					if($check['ip_address'] == '*') return false;
					if($domain['ip_address'] != '' && $check['ip_address'] == $domain['ip_address']) return false;
					if($domain['ipv6_address'] != '' && $check['ipv6_address'] == $domain['ipv6_address']) return false;
				}
			}
		}

		return true;
	}

	/* check if the client may add wildcard domains */
	function _wildcard_limit() {
		global $app;

		if($_SESSION["s"]["user"]["typ"] != 'admin') {
			// Get the limits of the client
			$client_group_id = $app->functions->intval($_SESSION["s"]["user"]["default_group"]);
			$client = $app->db->queryOneRecord("SELECT limit_wildcard FROM sys_group, client WHERE sys_group.client_id = client.client_id and sys_group.groupid = ?", $client_group_id);

			if($client["limit_wildcard"] == 'y') return true;
			else return false;
		}
		return true; // admin may always add wildcard domain
	}

	/**
	 * Parses $expression to check if it is a valid shell glob pattern.
	 * Does not support extended glob matching syntax.
	 *
	 * @see https://www.gnu.org/software/bash/manual/html_node/Pattern-Matching.html
	 * @param string $expression
	 * @param string $allowed_chars regexp of allowed characters in expression. ? and * are always allowed
	 * @param string|null $allowed_brace_chars regexp of allowed characters in brace ([...]). Dash is always allowed. If empty, then $allowed_chars will be used
	 * @return bool
	 */
	private function validate_glob($expression, $allowed_chars = '/^.$/u', $allowed_brace_chars = null) {
		$escaping = false;
		$in_brace = false;
		$brace_content = [];
		$chars = preg_split('//u', $expression, -1, PREG_SPLIT_NO_EMPTY);
		foreach($chars as $i => $c) {
			if($in_brace) {
				// the first char after brace start can be a ].
				if(($c == ']' && empty($brace_content)) || $c != ']') {
					$brace_content[] = $c;
				} else {
					$in_brace = false;
					$last_is_dash = false;
					foreach($brace_content as $bi => $bc) {
						// dashes are always allowed
						if($bc == '-') {
							// ... but we consider consecutive dashes as invalid
							if($last_is_dash) {
								return false;
							}
							// ... and need to validate it as allowed char when it is first or last
							if(($bi == 0 || $bi == count($brace_content) - 1) && !preg_match($allowed_brace_chars ?: $allowed_chars, '-')) {
								return false;
							}
							$last_is_dash = true;
						} else {
							$last_is_dash = false;
							// negate chars are always allowed
							if($bi == 0 && ($bc == '^' || $bc == '!') && count($brace_content) > 1) {
								continue;
							}
							if(!preg_match($allowed_brace_chars ?: $allowed_chars, $bc)) {
								return false;
							}
						}
					}
				}
			} else {
				$peek = $i == count($chars) - 1 ? '' : $chars[$i + 1];
				if($c == '\\' && in_array($peek, ['[', ']', '*', '?'])) {
					$escaping = true;
					continue;
				} elseif($c == '[' && !$escaping) {
					$in_brace = true;
					$brace_content = [];
				} elseif($escaping || ($c != '?' && $c != '*')) {
					if(!preg_match($allowed_chars, $c)) {
						return false;
					}
				}
				$escaping = false;
			}
		}
		return !$in_brace && !$escaping;
	}

	/**
	 * Validates that input is a comma separated list of domain globs.
	 * Can be used for fnmatch() as input.
	 */
	function domain_glob_list($field_name, $field_value, $validator) {
		global $app;
		$allowempty = $validator['allowempty'] ?: 'n';
		$exceptions = $validator['exceptions'] ?: [];
		$allow_exception_as_substring = $validator['allow_exception_as_substring'] ?: 'y';
		if(!$field_value) {
			if($allowempty == 'y') {
				return '';
			}
			return $this->get_error($validator['errmsg']);
		}
		$parts = explode(',', $field_value);
		foreach($parts as $part) {
			$part = trim($part);
			// an empty part means there is a stray comma
			if(empty($part)) {
				return $this->get_error($validator['errmsg']);
			}
			// allow list placeholders that you will replace with real values at evaluation
			if(in_array($part, $exceptions, true)) {
				continue;
			}
			// optionally do not allow placeholders to be part of an expression
			if($allow_exception_as_substring == 'n') {
				foreach($exceptions as $exception) {
					if(strpos($part, $exception) !== false) {
						return $this->get_error($validator['errmsg']);
					}
				}
			}
			// A domain glob needs to:
			// * be a valid glob with only a-z0-9._- as characters
			// * have at least one dot in it
			// * not have two consecutive dots
			if(!$this->validate_glob($part, '/^[a-z0-9._-]$/ui') || strpos($part, '.') === false || strpos($part, '..') !== false) {
				return $this->get_error($validator['errmsg']);
			}
		}
		return '';
	}

}