pfSense

diff --git a/src/etc/inc/dyndns.class b/src/etc/inc/dyndns.class
index 5c1f6ae0f4..23174464e3 100644
--- a/src/etc/inc/dyndns.class
+++ b/src/etc/inc/dyndns.class
@@ -196,7 +196,16 @@
         var $_dnsDummyUpdateDone;
         var $_forceUpdateNeeded;
         var $_checkIPMode;
-        var $_addressFamily;
+
+        /**
+         * The $_addressFamilyRR variable is used along with $_dnsIP to
+         * determine the data for the resource record. It is independent
+         * of $_addressFamilyRequest which determines the IP address
+         * family used to make the request itself.
+         */
+        var $_addressFamilyRR;
+        var $_addressFamilyRequest;
+
         var $_existingRecords;
         var $_curlProxy;

@@ -357,10 +366,10 @@
                 case 'route53-v6':
                 case 'spdyn-v6':
                 case 'yandex-v6':
-                    $this->_addressFamily = $this->_curlIpresolveV4 ? AF_INET : null;
+                    $this->_addressFamilyRR = AF_INET6;
                     break;
                 default:
-                    $this->_addressFamily = null;
+                    $this->_addressFamilyRR = AF_INET;
             }
             $this->_dnsService = strtolower($dnsService);
             $this->_dnsUser = $dnsUser;
@@ -378,10 +387,25 @@
             $this->_dnsUpdateURL = $dnsUpdateURL;
             $this->_dnsResultMatch = $dnsResultMatch;
             $this->_dnsRequestIf = $dnsRequestIf;
-            $this->_dnsRequestIfIP = get_request_source_address($this->_dnsRequestIf, $this->_addressFamily);
-            $this->_addressFamily = is_ipaddrv6($this->_dnsRequestIfIP) ? AF_INET6 : AF_INET;
+
+            /**
+             * The request's source IP address is chosen as follows:
+             * If IPv4 is forced by $_curlIpresolveV4 then the source IP
+             * is set to the primary IPv4 address of the "interface to
+             * monitor". When the "interface to monitor" only has either
+             * IPv4 or IPv6, the the respective "primary" address for the
+             * interface is chosen. If both IPv4 and IPv6 addresses exist
+             * on the "interface to monitor", the chosen address depends
+             * on the system preference ("prefer_ipv4").
+             * 
+             * To instead choose the source IP address based on the DNS RR
+             * type, replace 'null' with '$this->_addressFamilyRR'.
+             */
+            $this->_dnsRequestIfIP = get_request_source_address($this->_dnsRequestIf, ($this->_curlIpresolveV4 ? AF_INET : null));
+
+            $this->_addressFamilyRequest = is_ipaddrv6($this->_dnsRequestIfIP) ? AF_INET6 : AF_INET;
             $this->_checkIPMode = $checkIPMode;
-            $this->_dnsIP = dyndnsCheckIP($this->_dnsRequestIf, $this->_checkIPMode, $this->_addressFamily);
+            $this->_dnsIP = dyndnsCheckIP($this->_dnsRequestIf, $this->_checkIPMode, $this->_addressFamilyRR);

             if (($dnsMaxCacheAge !== null) && ($dnsMaxCacheAge !== "")) {
                 $this->_dnsMaxCacheAgeDays = (int)$dnsMaxCacheAge;
@@ -533,7 +557,7 @@

             $ch = curl_init();

-            curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamily == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));
+            curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamilyRequest == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));

             if ($this->_dnsService != 'ods') {
                 curl_setopt($ch, CURLOPT_USERAGENT, $this->_UserAgent);
@@ -875,7 +899,7 @@
                         https://{login}:{password}@https://api.mythic-beasts.com/dns/v2/zones/example.com/records/test1/A -d data=1.2.3.4
                     */
                     $needsIP = FALSE;
-                    if ($this->_addressFamily == AF_INET6) {
+                    if ($this->_addressFamilyRR == AF_INET6) {
                         $record = "AAAA";
                     } else {
                         $record = "A";
@@ -891,7 +915,7 @@
                     // API documentation: https://www.name.com/api-docs/ & https://www.name.com/api-docs/dns
                     $namedotcom_api = "https://api.name.com/v4/domains/{$this->_dnsDomain}/records";
                     curl_setopt($ch, CURLOPT_USERPWD, $this->_dnsUser . ':' . $this->_dnsPass);
-                    $record_type = ($this->_addressFamily == AF_INET6) ? "AAAA" : "A";
+                    $record_type = ($this->_addressFamilyRR == AF_INET6) ? "AAAA" : "A";
                     // Check if a record already exists for this host.
                     curl_setopt($ch, CURLOPT_URL, "{$namedotcom_api}?perPage=1000");
                     curl_setopt($ch, CURLOPT_FORBID_REUSE, true);
@@ -955,7 +979,7 @@
                 case 'porkbun-v6':
                     // API documentation: https://api.porkbun.com/api/json/v3/documentation
                     $porkbun_api = "https://api.porkbun.com/api/json/v3/dns/retrieve/{$this->_dnsDomain}";
-                    $record_type = ($this->_addressFamily == AF_INET6) ? "AAAA" : "A";
+                    $record_type = ($this->_addressFamilyRR == AF_INET6) ? "AAAA" : "A";
                     // Check if a record already exists for this host.
                     $post_data['apikey'] = $this->_dnsUser;
                     $post_data['secretapikey'] = $this->_dnsPass;
@@ -1003,7 +1027,7 @@
                     if (($record_id) &&
                         ($this->_forceUpdateNeeded == true) &&
                         ($this->_dnsDummyUpdateDone == false)) {
-                        $post_data['content'] = ($this->_addressFamily == AF_INET6) ? "fd00:d::1" : "127.0.0.1";
+                        $post_data['content'] = ($this->_addressFamilyRR == AF_INET6) ? "fd00:d::1" : "127.0.0.1";
                         $this->_dnsDummyUpdateDone = true;
                         $log_message = 'Dynamic DNS %1$s (%2$s): ';
                         $log_message .= 'Performing forced update. ';
@@ -1265,7 +1289,7 @@
                        Data sent as JSON */
                     $needsIP = TRUE;
                     $server = 'https://api.godaddy.com/v1/domains/';
-                    $recordType = ($this->_addressFamily == AF_INET6) ? "AAAA" : "A";
+                    $recordType = ($this->_addressFamilyRR == AF_INET6) ? "AAAA" : "A";
                     $url = $server . $this->_dnsDomain . '/records/' . $recordType . '/' . $this->_dnsHost;
                     $jsondata = '[{"data":"' . $this->_dnsIP . '","ttl":' . $this->_dnsTTL . '}]';
                     curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "PUT");
@@ -1636,7 +1660,7 @@
                         return false;
                     }
                         // Update the DNS record
-                    if ($this->_addressFamily == AF_INET6) {
+                    if ($this->_addressFamilyRR == AF_INET6) {
                         $url = "https://management.azure.com" . $resourceid . "/AAAA/" . $hostname . "?api-version=2017-09-01";
                         $body = '{"properties":{"TTL":"' . $newttl . '", "AAAARecords":[{"ipv6Address":"' . $newip . '"}]}}';
                     } else {
@@ -1658,7 +1682,7 @@
                 case 'linode':
                 case 'linode-v6':
                     $linode_api = "https://api.linode.com/v4";
-                    $record_type = ($this->_addressFamily == AF_INET6) ? "AAAA" : "A";
+                    $record_type = ($this->_addressFamilyRR == AF_INET6) ? "AAAA" : "A";
                     $record_name = $this->_dnsHost == "@" ? "" : $this->_dnsHost;
                     $err_prefix = gettext("Dynamic DNS") . " {$this->_dnsService} ({$this->_FQDN}): (" . gettext("Error") . ")";
                     curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
@@ -1755,7 +1779,7 @@
                     // https://api.gandi.net/docs/livedns/#v5-livedns-domains-fqdn-records-rrset_name-rrset_type
                     // PUT overrides the existing record or creates if none exists
                     $gandi_api = 'https://api.gandi.net/v5/livedns/domains/';
-                    $record_type = ($this->_addressFamily == AF_INET6) ? "AAAA" : "A";
+                    $record_type = ($this->_addressFamilyRR == AF_INET6) ? "AAAA" : "A";
                     $url = "{$gandi_api}{$this->_dnsDomain}/records/{$this->_dnsHost}/{$record_type}";

                     $headers = array(
@@ -1825,8 +1849,6 @@

             $ch = curl_init();

-            curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamily == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));
-
             curl_setopt($ch, CURLOPT_USERAGENT, $this->_UserAgent);
             curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
             curl_setopt($ch, CURLOPT_INTERFACE, $this->_dnsRequestIfIP);
@@ -1835,6 +1857,7 @@
             switch ($this->_dnsService) {
             case 'dreamhost':
             case 'dreamhost-v6':
+                curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamilyRequest == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));
                 $server = 'https://api.dreamhost.com/';
                 $post_data['key'] = $this->_dnsPass;
                 $post_data['unique_id'] = uniqid($this->_dnsHost);
@@ -1842,8 +1865,7 @@
                 $post_data['format'] = 'json';
                 $post_data['value'] = $existing_ip;
                 $post_data['record'] = $this->_dnsHost;
-                $isv6 = ($this->_dnsService === 'dreamhost-v6');
-                $post_data['type'] = $isv6 ? 'AAAA' : 'A';
+                $post_data['type'] = ($this->_addressFamilyRR == AF_INET6) ? 'AAAA' : 'A';
                 $port = "";
                 if ($this->_dnsServer) {
                     $server = $this->_dnsServer;
@@ -1856,6 +1878,12 @@
                 $remove_allowed = true;
                 break;
             default:
+                /**
+                 * When the resource record (RR) type is not specified for
+                 * the removal request, it is assumed that the RR being
+                 * removed is dependent on the request's IP address family.
+                 */
+                curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamilyRR == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));
                 break;
             }
             if ($remove_allowed) {
@@ -1886,7 +1914,7 @@

             $ch = curl_init();

-            curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamily == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));
+            curl_setopt($ch, CURLOPT_IPRESOLVE, (($this->_addressFamilyRequest == AF_INET6) ? CURL_IPRESOLVE_V6 : CURL_IPRESOLVE_V4));

             curl_setopt($ch, CURLOPT_USERAGENT, $this->_UserAgent);
             curl_setopt($ch, CURLOPT_RETURNTRANSFER, TRUE);
@@ -1957,8 +1985,8 @@
                 } else {
                     foreach($result["data"] as $key => $row) {
                         if($row["record"] == $this->_dnsHost &&
-                                (($row["type"] == "A" && ($this->_addressFamily == AF_INET))
-                                        || ($row["type"] == "AAAA" && ($this->_addressFamily == AF_INET6))
+                                (($row["type"] == "A" && ($this->_addressFamilyRR == AF_INET))
+                                        || ($row["type"] == "AAAA" && ($this->_addressFamilyRR == AF_INET6))
                                 )) {
                             if($row["editable"] == 0) {
                                 log_error($status_intro . "host " . $this->_dnsHost . " is not editable.");
@@ -3040,21 +3068,19 @@

             if ($successful_update == true) {
                 /* Write WAN IP to cache file */
-                $wan_ip = dyndnsCheckIP($this->_dnsRequestIf, $this->_checkIPMode, $this->_addressFamily);
-                $this->_dnsIP = $wan_ip;
-                if (($this->_addressFamily == AF_INET) && $wan_ip) {
+                if ($this->_addressFamilyRR == AF_INET) {
                     $currentTime = time();
-                    notify_all_remote(sprintf(gettext('DynDNS updated IP Address for %1$s on %2$s (%3$s) to %4$s'), $this->_FQDN, convert_real_interface_to_friendly_descr($this->_if), $this->_if, $wan_ip));
-                    log_error(sprintf(gettext('phpDynDNS: updating cache file %1$s: %2$s'), $this->_cacheFile, $wan_ip));
-                    @file_put_contents($this->_cacheFile, "{$wan_ip}|{$currentTime}");
+                    notify_all_remote(sprintf(gettext('DynDNS updated IP Address for %1$s on %2$s (%3$s) to %4$s'), $this->_FQDN, convert_real_interface_to_friendly_descr($this->_if), $this->_if, $this->_dnsIP));
+                    log_error(sprintf(gettext('phpDynDNS: updating cache file %1$s: %2$s'), $this->_cacheFile, $this->_dnsIP));
+                    @file_put_contents($this->_cacheFile, "{$this->_dnsIP}|{$currentTime}");
                 } else {
                     @unlink($this->_cacheFile);
                 }
-                if (($this->_addressFamily == AF_INET6) && $wan_ip) {
+                if ($this->_addressFamilyRR == AF_INET6) {
                     $currentTime = time();
-                    notify_all_remote(sprintf(gettext('DynDNS updated IPv6 Address for %1$s on %2$s (%3$s) to %4$s'), $this->_FQDN, convert_real_interface_to_friendly_descr($this->_if), $this->_if, $wan_ip));
-                    log_error(sprintf(gettext('phpDynDNS: updating cache file %1$s: %2$s'), $this->_cacheFile_v6, $wan_ip));
-                    @file_put_contents($this->_cacheFile_v6, "{$wan_ip}|{$currentTime}");
+                    notify_all_remote(sprintf(gettext('DynDNS updated IPv6 Address for %1$s on %2$s (%3$s) to %4$s'), $this->_FQDN, convert_real_interface_to_friendly_descr($this->_if), $this->_if, $this->_dnsIP));
+                    log_error(sprintf(gettext('phpDynDNS: updating cache file %1$s: %2$s'), $this->_cacheFile_v6, $this->_dnsIP));
+                    @file_put_contents($this->_cacheFile_v6, "{$this->_dnsIP}|{$currentTime}");
                 } else {
                     @unlink($this->_cacheFile_v6);
                 }
@@ -3126,15 +3152,14 @@

             $currentTime = time();

-            $wan_ip = dyndnsCheckIP($this->_dnsRequestIf, $this->_checkIPMode, $this->_addressFamily);
-            $this->_dnsIP = $wan_ip;
-            if (!$wan_ip) {
+            $this->_dnsIP = dyndnsCheckIP($this->_dnsRequestIf, $this->_checkIPMode, $this->_addressFamilyRR);
+            if (!$this->_dnsIP) {
                 log_error(sprintf(gettext("Dynamic Dns (%s): Current WAN IP could not be determined, skipping update process."), $this->_FQDN));
                 return false;
             }
-            $log_error = sprintf(gettext('Dynamic Dns (%1$s): Current WAN IP: %2$s'), $this->_FQDN, $wan_ip) . " ";
+            $log_error = sprintf(gettext('Dynamic Dns (%1$s): Current WAN IP: %2$s'), $this->_FQDN, $this->_dnsIP) . " ";

-            if (($this->_addressFamily == AF_INET6)) {
+            if (($this->_addressFamilyRR == AF_INET6)) {
                 if (file_exists($this->_cacheFile_v6)) {
                     $contents = file_get_contents($this->_cacheFile_v6);
                     list($cacheIP, $cacheTime) = explode('|', $contents);
@@ -3175,10 +3200,10 @@

             $needs_updating = FALSE;
             /* lets determine if the item needs updating */
-            if ($cacheIP != $wan_ip) {
+            if ($cacheIP != $this->_dnsIP) {
                 $needs_updating = true;
                 $update_reason = gettext("Dynamic Dns: cacheIP != wan_ip. Updating.") . " ";
-                $update_reason .= sprintf(gettext('Cached IP: %1$s WAN IP: %2$s'), $cacheIP, $wan_ip) . " ";
+                $update_reason .= sprintf(gettext('Cached IP: %1$s WAN IP: %2$s'), $cacheIP, $this->_dnsIP) . " ";
             }
             if (($currentTime - $cacheTime) > $maxCacheAgeSecs) {
                 $needs_updating = true;
diff --git a/src/usr/local/www/services_dyndns.php b/src/usr/local/www/services_dyndns.php
index 94a96f1833..372ff7b325 100644
--- a/src/usr/local/www/services_dyndns.php
+++ b/src/usr/local/www/services_dyndns.php
@@ -114,7 +114,7 @@ foreach (config_get_path("dyndnses/dyndns", []) as $dyndns):
     $filename = "{$g['conf_path']}/dyndns_{$dyndns['interface']}{$dyndns['type']}" . escapeshellarg($hostname) . "{$dyndns['id']}.cache";
     $filename_v6 = "{$g['conf_path']}/dyndns_{$dyndns['interface']}{$dyndns['type']}" . escapeshellarg($hostname) . "{$dyndns['id']}_v6.cache";
     if (file_exists($filename)) {
-        $ipaddr = dyndnsCheckIP($dyndns['interface'], array_get_path($dyndns, 'check_ip_mode'));
+        $ipaddr = dyndnsCheckIP($dyndns['interface'], array_get_path($dyndns, 'check_ip_mode'), AF_INET);
         $cached_ip_s = explode("|", file_get_contents($filename));
         $cached_ip = $cached_ip_s[0];

@@ -128,7 +128,7 @@ foreach (config_get_path("dyndnses/dyndns", []) as $dyndns):
             $icon_title = "Failed";
         }
     } else if (file_exists($filename_v6)) {
-        $ipv6addr = dyndnsCheckIP($dyndns['interface'], array_get_path($dyndns, 'check_ip_mode'));
+        $ipv6addr = dyndnsCheckIP($dyndns['interface'], array_get_path($dyndns, 'check_ip_mode'), AF_INET6);
         $cached_ipv6_s = explode("|", file_get_contents($filename_v6));
         $cached_ipv6 = $cached_ipv6_s[0];

diff --git a/src/usr/local/www/services_dyndns_edit.php b/src/usr/local/www/services_dyndns_edit.php
index 27cbb9877d..4648282906 100644
--- a/src/usr/local/www/services_dyndns_edit.php
+++ b/src/usr/local/www/services_dyndns_edit.php
@@ -255,7 +255,18 @@ if ($_POST['save'] || $_POST['force']) {
         }
         $dyndns['curl_proxy'] = $_POST['curl_proxy'] ? true : false;
         $dyndns['descr'] = $_POST['descr'];
-        $dyndns['force'] = isset($_POST['force']);
+
+        /**
+         * An update is forced when the interface changes because the IP
+         * for the new interface may already be cached; if that cache
+         * contains the same IP address as the new interface then the
+         * record is not updated.
+         */
+        if (isset($_POST['force']) || $dup || ($_POST['interface'] != $this_dyndns_config['interface'])) {
+            $dyndns['force'] = true;
+        } else {
+            $dyndns['force'] = false;
+        }

         if ($dyndns['username'] == "none") {
             $dyndns['username'] = "";