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| author | Andreas Fischer <bantu@phpbb.com> | 2010-05-19 17:42:44 +0200 |
|---|---|---|
| committer | Andreas Fischer <bantu@phpbb.com> | 2010-08-03 10:50:41 +0200 |
| commit | 24e23755cfe57afcf3125ba9c684b32942425696 (patch) | |
| tree | d84a41d33c75e7ac63640b44fa3656ed822a8fa9 /phpBB/includes/functions.php | |
| parent | 4707b0c18e314e3a2a4d58f942d77ff849fb4d3f (diff) | |
| download | forums-24e23755cfe57afcf3125ba9c684b32942425696.tar forums-24e23755cfe57afcf3125ba9c684b32942425696.tar.gz forums-24e23755cfe57afcf3125ba9c684b32942425696.tar.bz2 forums-24e23755cfe57afcf3125ba9c684b32942425696.tar.xz forums-24e23755cfe57afcf3125ba9c684b32942425696.zip | |
[ticket/9599] Reimplement phpbb_checkdnsrr() function.
Use gethostbyname(), checkdnsrr(), dns_get_record() or nslookup via exec().
PHPBB3-9599
Diffstat (limited to 'phpBB/includes/functions.php')
| -rw-r--r-- | phpBB/includes/functions.php | 169 |
1 files changed, 152 insertions, 17 deletions
diff --git a/phpBB/includes/functions.php b/phpBB/includes/functions.php index bc3d721de5..a61c28cb23 100644 --- a/phpBB/includes/functions.php +++ b/phpBB/includes/functions.php @@ -3440,26 +3440,110 @@ function short_ipv6($ip, $length) /** * Wrapper for php's checkdnsrr function. * -* The windows failover is from the php manual -* Please make sure to check the return value for === true and === false, since NULL could -* be returned too. +* @param string $host Fully-Qualified Domain Name +* @param string $type Resource record type to lookup +* Supported types are: MX (default), A, AAAA, NS, TXT, CNAME +* Other types may work or may not work * -* @return true if entry found, false if not, NULL if this function is not supported by this environment +* @return mixed true if entry found, +* false if entry not found, +* null if this function is not supported by this environment +* +* Since null can also be returned, you probably want to compare the result +* with === true or === false, +* +* @author bantu */ -function phpbb_checkdnsrr($host, $type = '') +function phpbb_checkdnsrr($host, $type = 'MX') { - $type = (!$type) ? 'MX' : $type; + // The dot indicates to search the DNS root (helps those having DNS prefixes on the same domain) + if (substr($host, -1) == '.') + { + $host_fqdn = $host; + $host = substr($host, 0, -1); + } + else + { + $host_fqdn = $host . '.'; + } + // $host has format some.host.example.com + // $host_fqdn has format some.host.example.com. - // Call checkdnsrr() if available. This is also the case on Windows with PHP 5.3 or later. - if (function_exists('checkdnsrr')) + // If we're looking for an A record we can use gethostbyname() + if ($type == 'A' && function_exists('gethostbyname')) { - // The dot indicates to search the DNS root (helps those having DNS prefixes on the same domain) - return checkdnsrr($host . '.', $type); + return (@gethostbyname($host_fqdn) == $host_fqdn) ? false : true; } - else if (DIRECTORY_SEPARATOR == '\\' && function_exists('exec')) + + // checkdnsrr() is available on Windows since PHP 5.3, + // but until 5.3.3 it only works for MX records + // See: http://bugs.php.net/bug.php?id=51844 + + // Call checkdnsrr() if + // we're looking for an MX record or + // we're not on Windows or + // we're running a PHP version where #51844 has been fixed + + // checkdnsrr() supports AAAA since 5.0.0 + // checkdnsrr() supports TXT since 5.2.4 + if ( + ($type == 'MX' || DIRECTORY_SEPARATOR != '\\' || version_compare(PHP_VERSION, '5.3.3', '>=')) && + ($type != 'AAAA' || version_compare(PHP_VERSION, '5.0.0', '>=')) && + ($type != 'TXT' || version_compare(PHP_VERSION, '5.2.4', '>=')) && + function_exists('checkdnsrr') + ) + { + return checkdnsrr($host_fqdn, $type); + } + + // dns_get_record() is available since PHP 5; since PHP 5.3 also on Windows, + // but on Windows it does not work reliable for AAAA records before PHP 5.3.1 + + // Call dns_get_record() if + // we're not looking for an AAAA record or + // we're not on Windows or + // we're running a PHP version where AAAA lookups work reliable + if ( + ($type != 'AAAA' || DIRECTORY_SEPARATOR != '\\' || version_compare(PHP_VERSION, '5.3.1', '>=')) && + function_exists('dns_get_record') + ) { - // @exec('nslookup -retry=1 -timout=1 -type=' . escapeshellarg($type) . ' ' . escapeshellarg($host), $output); - @exec('nslookup -type=' . escapeshellarg($type) . ' ' . escapeshellarg($host) . '.', $output); + // dns_get_record() expects an integer as second parameter + // We have to convert the string $type to the corresponding integer constant. + $type_constant = 'DNS_' . $type; + $type_param = (defined($type_constant)) ? constant($type_constant) : DNS_ANY; + + // dns_get_record() might throw E_WARNING and return false for records that do not exist + $resultset = @dns_get_record($host_fqdn, $type_param); + + if (empty($resultset) || !is_array($resultset)) + { + return false; + } + else if ($type_param == DNS_ANY) + { + // $resultset is a non-empty array + return true; + } + + foreach ($resultset as $result) + { + if ( + isset($result['host']) && $result['host'] == $host && + isset($result['type']) && $result['type'] == $type + ) + { + return true; + } + } + + return false; + } + + // If we're on Windows we can still try to call nslookup via exec() as a last resort + if (DIRECTORY_SEPARATOR == '\\' && function_exists('exec')) + { + @exec('nslookup -type=' . escapeshellarg($type) . ' ' . escapeshellarg($host_fqdn), $output); // If output is empty, the nslookup failed if (empty($output)) @@ -3469,15 +3553,66 @@ function phpbb_checkdnsrr($host, $type = '') foreach ($output as $line) { - if (!trim($line)) + $line = trim($line); + + if (empty($line)) { continue; } - // Valid records begin with host name: - if (strpos($line, $host) === 0) + // Squash tabs and multiple whitespaces to a single whitespace. + $line = preg_replace('/\s+/', ' ', $line); + + switch ($type) { - return true; + case 'MX': + if (stripos($line, "$host MX") === 0) + { + return true; + } + break; + + case 'NS': + if (stripos($line, "$host nameserver") === 0) + { + return true; + } + break; + + case 'TXT': + if (stripos($line, "$host text") === 0) + { + return true; + } + break; + + case 'CNAME': + if (stripos($line, "$host canonical name") === 0) + { + return true; + } + + default: + case 'A': + case 'AAAA': + if (!empty($host_matches)) + { + // Second line + if (stripos($line, "Address: ") === 0) + { + return true; + } + else + { + $host_matches = false; + } + } + else if (stripos($line, "Name: $host") === 0) + { + // First line + $host_matches = true; + } + break; } } |