- added the ZONEMD resource record type.

- added a new PHPUnit file to test the file cache. - added a new PHPUnit file to do real-time checks against a public internal server. - muted errors from stream_select(); it's safe to mute them since the error condition is handled. - double checked the class index exists first in Net_DNS2_RR::parse() before using it. - added a typehint for Net_DNS::$last_exception in the comments so PHPStorm doesn't complain. - added a quick check to confirm all the DNS servers are IP addresses. - cleaned up the logic around binding to a local host and/or port; some cases wouldn't have worked correctly. - PHP 8.0 issue: shmop_close() is deprecated in PHP 8. - PHP 8.0 issue: strlen() generates an error if you pass in null; there's a few placing the code that wasn't testing for this first. - PHP 8.0 issue: fread() throws an exception now if you set the length to 0; so I have to check the filesize() first before reading. - PHP 8.1 issue: passing null to preg_split() generates an error; there were three cases where it was possible.
mikepultz · Nov 28, 2022 · dc80537 · dc80537
1 parent 1284c4b
commit dc80537
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Showing 25 changed files with 653 additions and 236 deletions.
diff --git a/Net/DNS2.php b/Net/DNS2.php
@@ -184,6 +184,8 @@ class Net_DNS2
 
     /*
      * the last exeception that was generated
+     *
+     * @var Net_DNS2_Exception|null
      */
     public $last_exception = null;
 
@@ -193,7 +195,7 @@ class Net_DNS2
     public $last_exception_list = [];
 
     /*
-     * name server list
+     * name server list specified as IPv4 or IPv6 addresses
      */
     public $nameservers = [];
 
@@ -323,6 +325,17 @@ public function setServers($nameservers)
         //
         if (is_array($nameservers)) {
 
+            //
+            // make sure all the name servers are IP addresses (either v4 or v6)
+            //
+            foreach($nameservers as $value) {
+
+                if ( (self::isIPv4($value) == false) && (self::isIPv6($value) == false) ) {
+
+                    throw new Net_DNS2_Exception('invalid nameserver entry: ' . $value, Net_DNS2_Lookups::E_NS_INVALID_ENTRY);
+                }
+            }
+
             $this->nameservers = $nameservers;
 
         } else {
@@ -543,9 +556,10 @@ protected function checkServers($default = null)
     {
         if (empty($this->nameservers)) {
 
-            if (isset($default)) {
+            if (is_null($default) == false) {
 
                 $this->setServers($default);
+
             } else {
 
                 throw new Net_DNS2_Exception(
@@ -1093,7 +1107,7 @@ private function sendTCPRequest($_ns, $_data, $_axfr = false)
             //
             // if a local IP address / port is set, then add it
             //
-            if (strlen($this->local_host) > 0) {
+            if ( (strlen($this->local_host) > 0) || ($this->local_port > 0) ) {
 
                 $this->sock[Net_DNS2_Socket::SOCK_STREAM][$_ns]->bindAddress(
                     $this->local_host, $this->local_port
@@ -1303,7 +1317,7 @@ private function sendUDPRequest($_ns, $_data)
             //
             // if a local IP address / port is set, then add it
             //
-            if (strlen($this->local_host) > 0) {
+            if ( (strlen($this->local_host) > 0) || ($this->local_port > 0) ) {
 
                 $this->sock[Net_DNS2_Socket::SOCK_DGRAM][$_ns]->bindAddress(
                     $this->local_host, $this->local_port

diff --git a/Net/DNS2/Lookups.php b/Net/DNS2/Lookups.php
@@ -398,6 +398,7 @@ class Net_DNS2_Lookups
         60          => 'Net_DNS2_RR_CDNSKEY',
         61          => 'Net_DNS2_RR_OPENPGPKEY',
         62          => 'Net_DNS2_RR_CSYNC',
+        63          => 'Net_DNS2_RR_ZONEMD',
         99          => 'Net_DNS2_RR_SPF',
         104         => 'Net_DNS2_RR_NID',
         105         => 'Net_DNS2_RR_L32',

diff --git a/Net/DNS2/Names.php b/Net/DNS2/Names.php
@@ -0,0 +1,74 @@
+<?php
+
+/**
+ * DNS Library for handling lookups and updates. 
+ *
+ * Copyright (c) 2022, Mike Pultz <[email protected]>. All rights reserved.
+ *
+ * See LICENSE for more details.
+ *
+ * @category  Networking
+ * @package   Net_DNS2
+ * @author    Mike Pultz <[email protected]>
+ * @copyright 2022 Mike Pultz <[email protected]>
+ * @license   http://www.opensource.org/licenses/bsd-license.php  BSD License
+ * @link      https://netdns2.com/
+ * @since     File available since Release 1.5.3
+ *
+ */
+
+/**
+ * text compression/expansion and labeling class
+ *
+ */
+class Net_DNS2_Names
+{
+    /**
+     * pack a text string
+     *
+     * @param string $name a name to be packed
+     *
+     * @return string
+     * @access public
+     *
+     */
+    public static function pack($name)
+    {
+        return (is_null($name) == true) ? null : pack('Ca*', strlen($name), $name);
+    }
+
+    /**
+     * parses a domain string into a single string
+     *
+     * @param Net_DNS2_Packet &$packet the DNS packet to look in for the domain name
+     * @param integer         &$offset the offset into the given packet object
+     *
+     * @return mixed either a name string or null if it's not found.
+     * @access public
+     *
+     */
+    public static function unpack($rdata, &$offset)
+    {
+        $name = '';
+
+        if (strlen($rdata) < ($offset + 1))
+        {
+            return null;
+        }
+
+        $xlen = ord($rdata[$offset]);
+        ++$offset;
+
+        if (($xlen + $offset) > strlen($rdata)) {
+
+            $name = substr($rdata, $offset);
+            $offset = strlen($rdata);
+        } else {
+
+            $name = substr($rdata, $offset, $xlen);
+            $offset += $xlen;
+        }
+
+        return trim($name, '.');
+    }
+}
diff --git a/Net/DNS2/Packet.php b/Net/DNS2/Packet.php
@@ -214,39 +214,6 @@ public function compress($name, &$offset)
         return $compname;
     }
 
-    /**
-     * applies a standard DNS name compression on the given name/offset
-     *
-     * This logic was based on the Net::DNS::Packet::dn_comp() function 
-     * by Michanel Fuhr
-     *
-     * @param string $name the name to be compressed
-     *
-     * @return string
-     * @access public
-     *
-     */
-    public static function pack($name)
-    {
-        $offset = 0;
-        $names = explode('.', $name);
-        $compname = '';
-
-        while (!empty($names)) {
-
-            $first = array_shift($names);
-            $length = strlen($first);
-
-            $compname .= pack('Ca*', $length, $first);
-            $offset += $length + 1;
-        }
-
-        $compname .= "\0";
-        $offset++;
-
-        return $compname;
-    }
-
     /**
      * expands the domain name stored at a given offset in a DNS Packet
      *
@@ -322,6 +289,23 @@ public static function expand(Net_DNS2_Packet &$packet, &$offset, $escape_dot_li
         return trim($name, '.');
     }
 
+    /**
+     * applies a standard DNS name compression on the given name/offset
+     *
+     * This logic was based on the Net::DNS::Packet::dn_comp() function 
+     * by Michanel Fuhr
+     *
+     * @param string $name the name to be compressed
+     *
+     * @return string
+     * @access public
+     *
+     */
+    public static function pack($name)
+    {
+        return (is_null($name) == true) ? null : pack('Ca*', strlen($name), $name);
+    }
+
     /**
      * parses a domain label from a DNS Packet at the given offset
      *
@@ -332,29 +316,29 @@ public static function expand(Net_DNS2_Packet &$packet, &$offset, $escape_dot_li
      * @access public
      *
      */
-    public static function label(Net_DNS2_Packet &$packet, &$offset)
+    public static function label($rdata, &$offset)
     {
         $name = '';
 
-        if ($packet->rdlength < ($offset + 1)) {
-
+        if (strlen($rdata) < ($offset + 1))
+        {
             return null;
         }
 
-        $xlen = ord($packet->rdata[$offset]);
+        $xlen = ord($rdata[$offset]);
         ++$offset;
 
-        if (($xlen + $offset) > $packet->rdlength) {
+        if (($xlen + $offset) > strlen($rdata)) {
 
-            $name = substr($packet->rdata, $offset);
-            $offset = $packet->rdlength;
+            $name = substr($rdata, $offset);
+            $offset = strlen($rdata);
         } else {
 
-            $name = substr($packet->rdata, $offset, $xlen);
+            $name = substr($rdata, $offset, $xlen);
             $offset += $xlen;
         }
 
-        return $name;
+        return trim($name, '.');
     }
 
     /**

diff --git a/Net/DNS2/RR.php b/Net/DNS2/RR.php
@@ -55,7 +55,7 @@ abstract class Net_DNS2_RR
     /*
      * The name of the resource record
      */
-    public $name;
+    public $name = '';
 
     /*
      * The resource record type
@@ -374,7 +374,13 @@ public function get(Net_DNS2_Packet &$packet)
         //
         // add the RR
         //
-        $data .= pack('n', strlen($rdata)) . $rdata;
+        if ( (is_null($rdata) == false) && (strlen($rdata) > 0) ) {
+
+            $data .= pack('n', strlen($rdata)) . $rdata;
+        } else
+        {
+            $data .= pack('n', 0);
+        }
 
         return $data;
     }
@@ -432,31 +438,28 @@ public static function parse(Net_DNS2_Packet &$packet)
                                 ord($packet->rdata[$packet->offset++]);
 
         if ($packet->rdlength < ($packet->offset + $object['rdlength'])) {
-            return null;
+
+            throw new Net_DNS2_Exception(
+                'failed to parse resource record: packet too small.',
+                Net_DNS2_Lookups::E_PARSE_ERROR
+            );
         }
 
         //
         // lookup the class to use
         //
-        $o      = null;
-        $class  = Net_DNS2_Lookups::$rr_types_id_to_class[$object['type']];
-
-        if (isset($class)) {
+        if ( (isset(Net_DNS2_Lookups::$rr_types_id_to_class[$object['type']]) == true) &&
+            (class_exists(Net_DNS2_Lookups::$rr_types_id_to_class[$object['type']]) == true) ) {
 
-            $o = new $class($packet, $object);
+            $o = new Net_DNS2_Lookups::$rr_types_id_to_class[$object['type']]($packet, $object);
             if ($o) {
-
-                $packet->offset += $object['rdlength'];
+                $packet->offset += $object['rdlength'];            
             }
-        } else {
 
-            throw new Net_DNS2_Exception(
-                'un-implemented resource record type: ' . $object['type'],
-                Net_DNS2_Lookups::E_RR_INVALID
-            );
+            return $o;
         }
 
-        return $o;
+        throw new Net_DNS2_Exception('un-implemented resource record type: ' . $object['type'], Net_DNS2_Lookups::E_RR_INVALID);
     }
 
     /**
@@ -471,7 +474,7 @@ public static function parse(Net_DNS2_Packet &$packet)
      */
     public function cleanString($data)
     {
-        return strtolower(rtrim($data, '.'));
+        return (is_null($data) == true) ? null : strtolower(rtrim($data, '.'));
     }
 
     /**
@@ -495,7 +498,8 @@ public function cleanString($data)
      */
     public static function fromString($line)
     {
-        if (strlen($line) == 0) {
+        if ( (is_null($line) == true) || (strlen($line) == 0) ) {
+
             throw new Net_DNS2_Exception(
                 'empty config line provided.',
                 Net_DNS2_Lookups::E_PARSE_ERROR

diff --git a/Net/DNS2/RR/AMTRELAY.php b/Net/DNS2/RR/AMTRELAY.php
@@ -195,9 +195,7 @@ protected function rrSet(Net_DNS2_Packet &$packet)
                 break;
 
             case self::AMTRELAY_TYPE_DOMAIN:
-                $doffset = $packet->offset + $offset;
-                $this->relay = Net_DNS2_Packet::label($packet, $doffset);
-
+                $this->relay = Net_DNS2_Names::unpack($this->rdata, $offset);
                 break;
 
             default:
@@ -245,7 +243,8 @@ protected function rrGet(Net_DNS2_Packet &$packet)
             break;
 
         case self::AMTRELAY_TYPE_DOMAIN:
-            $data .= pack('Ca*', strlen($this->relay), $this->relay);
+            $data .= Net_DNS2_Names::pack($this->relay);
+            $packet->offset += 1;
             break;
 
         default:

diff --git a/Net/DNS2/RR/HINFO.php b/Net/DNS2/RR/HINFO.php
@@ -89,8 +89,8 @@ protected function rrSet(Net_DNS2_Packet &$packet)
 
             $offset = $packet->offset;
 
-            $this->cpu  = Net_DNS2_Packet::label($packet, $offset);
-            $this->os   = Net_DNS2_Packet::label($packet, $offset);
+            $this->cpu  = Net_DNS2_Names::unpack($packet->rdata, $offset);
+            $this->os   = Net_DNS2_Names::unpack($packet->rdata, $offset);
 
             return true;
         }
@@ -113,7 +113,7 @@ protected function rrGet(Net_DNS2_Packet &$packet)
     {
         if (strlen($this->cpu) > 0) {
 
-            $data = pack('Ca*Ca*', strlen($this->cpu), $this->cpu, strlen($this->os), $this->os);
+            $data = Net_DNS2_Names::pack($this->cpu) . Net_DNS2_Names::pack($this->os);
 
             $packet->offset += strlen($data);