Manage reverse records when adding or removing forward ones

model/zone.php

@@ -134,7 +134,6 @@ public function add_or_update_resource_record_set(ResourceRecordSet $rrset) {
 			$change_record->type = $rrset->type;
 			$change_record->content = $record->content;
 			$change_record->disabled = $record->disabled;
-			$change_record->{'set-ptr'} = $record->{'set-ptr'};
 			$change->records[] = $change_record;
 		}
 		$change->comments = array();
@@ -807,10 +806,8 @@ private function process_rrset_action($update, &$trash, &$revs_missing, &$revs_u
 				$rr = new ResourceRecord;
 				$rr->content = $record->content;
 				$rr->disabled = ($record->enabled === 'No' || $record->enabled === false);
-				if(!$autocreate_ptr || $rr->disabled) {
-					$rr->{'set-ptr'} = false;
-				} else {
-					$rr->{'set-ptr'} = $zone_dir->check_reverse_record_zone($rrset->name, $rrset->type, $rr->content, $revs_missing, $revs_updated);
+				if($autocreate_ptr && !$rr->disabled) {
+					$zone_dir->create_reverse_record($rrset->name, $rrset->type, $rr->content, $rrset->ttl, $revs_missing, $revs_updated);
 				}
 				$rrset->add_resource_record($rr);
 			}
@@ -840,16 +837,19 @@ private function process_rrset_action($update, &$trash, &$revs_missing, &$revs_u
 			$rrset->ttl = DNSTime::expand($update->ttl);
 			$record_count = 0;
 			foreach($update->records as $record) {
-				if(!empty($record->delete)) continue;
+				if(!empty($record->delete)) {
+					if(!empty($record->remove_ptr) && ($update->oldtype == 'A' || $update->oldtype == 'AAAA')) {
+						$zone_dir->delete_reverse_record($update->oldname, $update->oldtype, $record->content, $revs_updated);
+					}
+					continue;
+				}
 				$record_count++;
 				$record->content = DNSContent::encode($record->content, $update->type, $this->name);
 				$rr = new ResourceRecord;
 				$rr->content = $record->content;
 				$rr->disabled = ($record->enabled === 'No' || $record->enabled === false);
-				if(!$autocreate_ptr || $rr->disabled) {
-					$rr->{'set-ptr'} = false;
-				} else {
-					$rr->{'set-ptr'} = $zone_dir->check_reverse_record_zone($rrset->name, $rrset->type, $rr->content, $revs_missing, $revs_updated);
+				if($autocreate_ptr && !$rr->disabled) {
+					$zone_dir->create_reverse_record($rrset->name, $rrset->type, $rr->content, $rrset->ttl, $revs_missing, $revs_updated);
 				}
 				$rrset->add_resource_record($rr);
 			}
@@ -871,8 +871,14 @@ private function process_rrset_action($update, &$trash, &$revs_missing, &$revs_u
 			if(!isset($this->rrsets[$update->oldname.' '.$update->oldtype])) {
 				throw new BadData('Tried to delete a non-existent resource recordset: '.$update->oldname.' '.$update->oldtype.'.');
 			}
-			$change->before = serialize($this->rrsets[$update->oldname.' '.$update->oldtype]);
-			$this->delete_resource_record_set($this->rrsets[$update->oldname.' '.$update->oldtype]);
+			$rrset = $this->rrsets[$update->oldname.' '.$update->oldtype];
+			$change->before = serialize($rrset);
+			if(!empty($update->remove_ptr) && ($update->oldtype == 'A' || $update->oldtype == 'AAAA')) {
+				foreach($rrset->list_resource_records() as $rr) {
+					$zone_dir->delete_reverse_record($update->oldname, $update->oldtype, $rr->content, $revs_updated);
+				}
+			}
+			$this->delete_resource_record_set($rrset);
 			break;
 		}
 		return $change;

model/zonedirectory.php

@@ -224,14 +224,18 @@ public function list_accounts() {
 	}
 
 	/**
-	* Check the list of zones to see if a suitable reverse zone exists for the forward record.
+	* Check the list of zones to see if a suitable reverse zone exists for the forward record, and if
+	* so create/update the matching PTR record via a direct call to the PowerDNS API.
+	* PowerDNS's own "set-ptr" record attribute that used to do this automatically has been removed,
+	* so DNS UI must create the PTR record itself.
 	* @param string $name of DNS record
 	* @param string $type of DNS record
 	* @param string $address that DNS record points to
+	* @param int $ttl to use for the PTR record
 	* @param array $revs_missing keep track of reverse zones that are missing
 	* @param array $revs_updated keep track of reverse zones that will be updated
 	*/
-	public function check_reverse_record_zone($name, $type, $address, &$revs_missing, &$revs_notify) {
+	public function create_reverse_record($name, $type, $address, $ttl, &$revs_missing, &$revs_notify) {
 		global $zone_dir, $active_user;
 
 		if($type == 'A') {
@@ -270,6 +274,25 @@ public function check_reverse_record_zone($name, $type, $address, &$revs_missing
 						}
 					}
 				}
+				// Create the PTR record directly via the PowerDNS API
+				$ptr_rrset = new ResourceRecordSet;
+				$ptr_rrset->name = $reverse_address;
+				$ptr_rrset->type = 'PTR';
+				$ptr_rrset->ttl = $ttl;
+				$ptr_record = new ResourceRecord;
+				$ptr_record->content = $name;
+				$ptr_record->disabled = false;
+				$ptr_rrset->add_resource_record($ptr_record);
+				try {
+					$reverse_zone->add_or_update_resource_record_set($ptr_rrset);
+					$reverse_zone->commit_changes();
+				} catch(ResourceRecordInvalid $e) {
+					$alert = new UserAlert;
+					$alert->content = "Failed to create reverse record for $address pointing to $name: ".$e->getMessage();
+					$alert->class = 'warning';
+					$active_user->add_alert($alert);
+					return false;
+				}
 				// Add reverse zone to list of zones to send a notify for
 				$revs_notify[$reverse_zone->pdns_id] = $reverse_zone;
 				return true;
@@ -284,6 +307,109 @@ public function check_reverse_record_zone($name, $type, $address, &$revs_missing
 		return false;
 	}
 
+	/**
+	* Locate the reverse (PTR) RRset for a forward record's address, if one exists.
+	* Searches for an appropriate reverse zone by starting with the full domain name, and
+	* removing subdomains until a match is found or there is nothing left to remove.
+	* @param string $type of forward DNS record (A or AAAA)
+	* @param string $address that the forward DNS record points to
+	* @return array|null array(Zone $reverse_zone, ResourceRecordSet $rrset), or null if none found
+	*/
+	private function find_reverse_rrset($type, $address) {
+		global $zone_dir;
+
+		if($type == 'A') {
+			$reverse_address = implode('.', array_reverse(explode('.', $address))).'.in-addr.arpa.';
+		} elseif($type == 'AAAA') {
+			$address = ipv6_address_expand($address);
+			$reverse_address = implode('.', array_reverse(str_split(str_replace(':', '', $address)))).'.ip6.arpa.';
+		} else {
+			return null;
+		}
+		$reverse_zone_name = $reverse_address;
+		do {
+			try {
+				$reverse_zone = $zone_dir->get_zone_by_name($reverse_zone_name);
+				foreach($reverse_zone->list_resource_record_sets() as $rrset) {
+					if($rrset->name == $reverse_address && $rrset->type == 'PTR') {
+						return array($reverse_zone, $rrset);
+					}
+				}
+				return null;
+			} catch(ZoneNotFound $e) {
+			}
+		} while($this->remove_subdomain($reverse_zone_name));
+		return null;
+	}
+
+	/**
+	* Check whether a reverse (PTR) record exists pointing back at the given forward record.
+	* @param string $name of DNS record
+	* @param string $type of DNS record
+	* @param string $address that DNS record points to
+	* @return bool true if a matching PTR record exists
+	*/
+	public function has_reverse_record($name, $type, $address) {
+		$found = $this->find_reverse_rrset($type, $address);
+		if(is_null($found)) return false;
+		list(, $rrset) = $found;
+		foreach($rrset->list_resource_records() as $rr) {
+			if($rr->content == $name) return true;
+		}
+		return false;
+	}
+
+	/**
+	* Check the list of zones to see if a suitable reverse zone exists for the forward record, and if
+	* so remove the matching PTR record via a direct call to the PowerDNS API.
+	* @param string $name of DNS record whose PTR record should be removed
+	* @param string $type of DNS record
+	* @param string $address that DNS record pointed to
+	* @param array $revs_notify keep track of reverse zones that will be updated
+	* @return bool true if a PTR record was found and removed
+	*/
+	public function delete_reverse_record($name, $type, $address, &$revs_notify) {
+		global $active_user;
+
+		$found = $this->find_reverse_rrset($type, $address);
+		if(is_null($found)) return false;
+		list($reverse_zone, $rrset) = $found;
+		$remaining_rrs = array();
+		$matched = false;
+		foreach($rrset->list_resource_records() as $rr) {
+			if($rr->content == $name) {
+				$matched = true;
+			} else {
+				$remaining_rrs[] = $rr;
+			}
+		}
+		if(!$matched) return false;
+		try {
+			if(count($remaining_rrs) == 0) {
+				$reverse_zone->delete_resource_record_set($rrset);
+			} else {
+				$new_rrset = new ResourceRecordSet;
+				$new_rrset->name = $rrset->name;
+				$new_rrset->type = $rrset->type;
+				$new_rrset->ttl = $rrset->ttl;
+				foreach($remaining_rrs as $rr) {
+					$new_rrset->add_resource_record($rr);
+				}
+				$reverse_zone->add_or_update_resource_record_set($new_rrset);
+			}
+			$reverse_zone->commit_changes();
+		} catch(ResourceRecordInvalid $e) {
+			$alert = new UserAlert;
+			$alert->content = "Failed to remove reverse record for $address pointing to $name: ".$e->getMessage();
+			$alert->class = 'warning';
+			$active_user->add_alert($alert);
+			return false;
+		}
+		// Add reverse zone to list of zones to send a notify for
+		$revs_notify[$reverse_zone->pdns_id] = $reverse_zone;
+		return true;
+	}
+
 	/**
 	* Given a DNS name, remove the bottom-level subdomain from it.
 	* @param string $address DNS name

public_html/extra.js

@@ -109,10 +109,34 @@ $(function() {
 				button.append(' Delete');
 				tr.removeClass('delete');
 				tr.data('delete', false);
+				tr.data('remove-ptr', false);
+				update_changed(button);
 			} else {
 				button.text('Undelete');
 				tr.addClass('delete');
 				tr.data('delete', true);
+				if(!tr.data('newrow') && (tr.data('type') == 'A' || tr.data('type') == 'AAAA')) {
+					var content = $('td.content input', tr).val();
+					// Only bother asking if a matching reverse (PTR) record actually exists
+					$.ajax({
+						url: '../api/v2/zones/' + encodeURIComponent(form.data('zone')) + '/reverse-records',
+						method: 'GET',
+						data: {name: tr.data('name'), type: tr.data('type'), address: content},
+						dataType: 'json'
+					}).done(function(response) {
+						if(response && response.exists) {
+							tr.data('remove-ptr', confirm('A reverse (PTR) record exists pointing to ' + content + '. Also remove it?'));
+						} else {
+							tr.data('remove-ptr', false);
+						}
+					}).fail(function() {
+						tr.data('remove-ptr', false);
+					}).always(function() {
+						update_changed(button);
+					});
+					return;
+				}
+				tr.data('remove-ptr', false);
 			}
 			update_changed(button);
 		}
@@ -309,10 +333,15 @@ $(function() {
 						rrchanged = true;
 						rrspan.appendChild(document.createTextNode(' '));
 						var span = document.createElement('span');
-						$(span).text('Resource record deleted.');
+						var deletetext = 'Resource record deleted.';
+						if($(this).data('remove-ptr')) deletetext += ' Reverse (PTR) record will also be removed.';
+						$(span).text(deletetext);
 						$(span).addClass('text-warning');
 						rrspan.appendChild(span);
 						record['delete'] = true;
+						if(update.type == 'A' || update.type == 'AAAA') {
+							record['remove_ptr'] = !!$(this).data('remove-ptr');
+						}
 					} else {
 						activerows++;
 						if(record['enabled'] == 'Yes') enabledrows++;

views/api.php

@@ -28,6 +28,10 @@
 					} else {
 						$api->zone_changes($router->vars['id']);
 					}
+					break;
+				case 'reverse-records':
+					$api->zone_reverse_records($router->vars['id']);
+					break;
 				}
 			} else {
 				$api->zone($router->vars['id']);
@@ -148,6 +152,21 @@ public function update_zone_rrsets($zone_name) {
 		$this->output(null);
 	}
 
+	public function zone_reverse_records($zone_name) {
+		$this->options(array('GET' => 'check_zone_reverse_record'), array($zone_name));
+	}
+
+	public function check_zone_reverse_record($zone_name) {
+		global $zone_dir, $active_user;
+		$zone = $zone_dir->get_zone_by_name($zone_name);
+		if(!$active_user->admin && !$active_user->access_to($zone)) throw new AccessDenied;
+		if(!isset($_GET['name']) || !isset($_GET['type']) || !isset($_GET['address'])) throw new BadData('Missing required parameters.');
+		if($_GET['type'] != 'A' && $_GET['type'] != 'AAAA') throw new BadData('Type must be A or AAAA.');
+		$name = utf8_to_punycode(DNSName::canonify($_GET['name'], $zone->name));
+		$exists = $zone_dir->has_reverse_record($name, $_GET['type'], $_GET['address']);
+		$this->output(array('exists' => $exists));
+	}
+
 	public function zone_changes($zone_name) {
 		$this->options(array('GET' => 'list_zone_changes'), array($zone_name));
 	}