fix(activesync): stabilize folder UIDs after hierarchy changes

lib/Horde/ActiveSync/Driver/Base.php

@@ -414,8 +414,19 @@ protected function _getFolderUidForBackendId($id, $type = null, $old_id = null)
         $rMap = array_flip($this->_typeMap);
         $prefix = $rMap[$type];
 
-        // None found, generate a new UID.
-        $this->_tempMap[$id] = sprintf('%s%04x%04x', $prefix, mt_rand(0, 0xffff), mt_rand(0, 0xffff));
+        // None found, generate a new UID. This is derived deterministically
+        // from the backend id (rather than mt_rand()) so that concurrent or
+        // repeated cache rebuilds for the same device (e.g. multiple EAS
+        // sessions racing a FolderSync reset after a hierarchy change such as
+        // moving contacts between address books) always reproduce the same UID
+        // for a given folder instead of a different random one each time.
+        // A random UID here made every reset diverge from the last one,
+        // which could cascade into devices with several concurrent
+        // Mail/Calendar/Contacts/Tasks/Notes sessions repeatedly invalidating
+        // each other's synckey and never settling.
+        //
+        // @author Torben Dannhauer <torben@dannhauer.de>
+        $this->_tempMap[$id] = sprintf('%s%08x', $prefix, crc32($prefix . ':' . $id));
         $this->_logger->meta(
             sprintf(
                 'Creating new folder uuid for %s: %s',

lib/Horde/ActiveSync/Request/MoveItems.php

@@ -115,8 +115,8 @@ protected function _handle()
                 $status = self::STATUS_SAME_FOLDERS;
             } else {
                 $importer = $this->_activeSync->getImporter();
-                $importer->init($this->_state, $move[self::SRCFLDKEY]);
                 try {
+                    $importer->init($this->_state, $move[self::SRCFLDKEY]);
                     $move_res = $importer->importMessageMove(
                         [$move[self::SRCMSGKEY]],
                         $move[self::DSTFLDKEY]
@@ -133,6 +133,9 @@ protected function _handle()
                     } else {
                         $new_msgid = $move_res['results'][$move[self::SRCMSGKEY]];
                     }
+                } catch (Horde_ActiveSync_Exception_FolderGone $e) {
+                    $this->_logger->err($e->getMessage());
+                    $status = self::STATUS_INVALID_SRC;
                 } catch (Horde_ActiveSync_Exception $e) {
                     $this->_logger->err($e->getMessage());
                     $status = self::STATUS_INVALID_SRC;

test/unit/Horde/ActiveSync/FolderUidDeterministicTest.php

@@ -0,0 +1,99 @@
+<?php
+
+/**
+ * Unit tests for deterministic EAS folder UID generation.
+ *
+ * @author    Torben Dannhauer <torben@dannhauer.de>
+ * @license   http://www.horde.org/licenses/gpl GPLv2
+ * @copyright 2026 The Horde Project (http://www.horde.org/)
+ * @package   ActiveSync
+ */
+
+namespace Horde\ActiveSync;
+
+use Horde_ActiveSync;
+use Horde_ActiveSync_Driver_Base;
+use Horde_ActiveSync_State_Base;
+use PHPUnit\Framework\Attributes\CoversNothing;
+use PHPUnit\Framework\TestCase;
+use ReflectionMethod;
+
+#[CoversNothing]
+class FolderUidDeterministicTest extends TestCase
+{
+    public function testFolderUidIsDeterministicForRepeatedLookups()
+    {
+        $state = $this->createMock(Horde_ActiveSync_State_Base::class);
+        $state->method('getFolderUidToBackendIdMap')->willReturn([]);
+
+        $driver = $this->getMockBuilder(Horde_ActiveSync_Driver_Base::class)
+            ->setConstructorArgs([['state' => $state]])
+            ->getMockForAbstractClass();
+
+        $method = new ReflectionMethod(Horde_ActiveSync_Driver_Base::class, '_getFolderUidForBackendId');
+        $method->setAccessible(true);
+
+        $inbox = $method->invoke($driver, 'INBOX', Horde_ActiveSync::FOLDER_TYPE_INBOX);
+        $again = $method->invoke($driver, 'INBOX', Horde_ActiveSync::FOLDER_TYPE_INBOX);
+
+        $this->assertSame($inbox, $again);
+        $this->assertSame(
+            'F' . sprintf('%08x', crc32('F:' . 'INBOX')),
+            $inbox
+        );
+    }
+
+    public function testFolderUidIsDeterministicAcrossDriverInstances()
+    {
+        $state = $this->createMock(Horde_ActiveSync_State_Base::class);
+        $state->method('getFolderUidToBackendIdMap')->willReturn([]);
+
+        $method = new ReflectionMethod(Horde_ActiveSync_Driver_Base::class, '_getFolderUidForBackendId');
+        $method->setAccessible(true);
+
+        $driverA = $this->getMockBuilder(Horde_ActiveSync_Driver_Base::class)
+            ->setConstructorArgs([['state' => $state]])
+            ->getMockForAbstractClass();
+        $driverB = $this->getMockBuilder(Horde_ActiveSync_Driver_Base::class)
+            ->setConstructorArgs([['state' => $state]])
+            ->getMockForAbstractClass();
+
+        $contactBackendId = Horde_ActiveSync::CLASS_CONTACTS . ':42';
+        $uidA = $method->invoke(
+            $driverA,
+            $contactBackendId,
+            Horde_ActiveSync::FOLDER_TYPE_USER_CONTACT
+        );
+        $uidB = $method->invoke(
+            $driverB,
+            $contactBackendId,
+            Horde_ActiveSync::FOLDER_TYPE_USER_CONTACT
+        );
+
+        $this->assertSame($uidA, $uidB);
+        $this->assertSame(
+            'C' . sprintf('%08x', crc32('C:' . $contactBackendId)),
+            $uidA
+        );
+    }
+
+    public function testFolderUidUsesPersistedMapWhenPresent()
+    {
+        $state = $this->createMock(Horde_ActiveSync_State_Base::class);
+        $state->method('getFolderUidToBackendIdMap')->willReturn([
+            'INBOX' => 'F85953279',
+        ]);
+
+        $driver = $this->getMockBuilder(Horde_ActiveSync_Driver_Base::class)
+            ->setConstructorArgs([['state' => $state]])
+            ->getMockForAbstractClass();
+
+        $method = new ReflectionMethod(Horde_ActiveSync_Driver_Base::class, '_getFolderUidForBackendId');
+        $method->setAccessible(true);
+
+        $this->assertSame(
+            'F85953279',
+            $method->invoke($driver, 'INBOX', Horde_ActiveSync::FOLDER_TYPE_INBOX)
+        );
+    }
+}

test/unit/Horde/ActiveSync/MoveItemsFolderGoneTest.php

@@ -0,0 +1,224 @@
+<?php
+
+/**
+ * Unit tests for MoveItems handling of stale folder UIDs.
+ *
+ * @author    Torben Dannhauer <torben@dannhauer.de>
+ * @license   http://www.horde.org/licenses/gpl GPLv2
+ * @copyright 2026 The Horde Project (http://www.horde.org/)
+ * @package   ActiveSync
+ */
+
+namespace Horde\ActiveSync;
+
+use Horde_ActiveSync;
+use Horde_ActiveSync_Connector_Importer;
+use Horde_ActiveSync_Driver_Base;
+use Horde_ActiveSync_Exception_FolderGone;
+use Horde_ActiveSync_Log_Logger;
+use Horde_ActiveSync_Request_MoveItems;
+use Horde_ActiveSync_State_Base;
+use Horde_ActiveSync_Wbxml;
+use Horde_ActiveSync_Wbxml_Decoder;
+use Horde_ActiveSync_Wbxml_Encoder;
+use Horde_Controller_Request_Mock;
+use Horde_Log_Handler_Null;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use ReflectionMethod;
+use ReflectionProperty;
+
+#[CoversClass(Horde_ActiveSync_Request_MoveItems::class)]
+class MoveItemsFolderGoneTest extends TestCase
+{
+    protected function tearDown(): void
+    {
+        $deviceRef = new ReflectionProperty(Horde_ActiveSync::class, '_device');
+        $deviceRef->setAccessible(true);
+        $deviceRef->setValue(null, null);
+        parent::tearDown();
+    }
+
+    public function testMoveItemsReturnsInvalidSrcWhenSourceFolderIsGone()
+    {
+        $fixture = $this->_createHandler();
+        $fixture->importer->expects($this->once())
+            ->method('init')
+            ->willThrowException(new Horde_ActiveSync_Exception_FolderGone('Folder not found in cache.'));
+
+        $this->_writeWbxml($fixture->input, function (Horde_ActiveSync_Wbxml_Encoder $encoder) {
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::MOVES);
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::MOVE);
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::SRCMSGID);
+            $encoder->content('169462');
+            $encoder->endTag();
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::SRCFLDID);
+            $encoder->content('F85953279');
+            $encoder->endTag();
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::DSTFLDID);
+            $encoder->content('F37c56728');
+            $encoder->endTag();
+            $encoder->endTag();
+            $encoder->endTag();
+        });
+        $fixture->decoder->readWbxmlHeader();
+
+        $method = new ReflectionMethod(Horde_ActiveSync_Request_MoveItems::class, '_handle');
+        $method->setAccessible(true);
+        $this->assertTrue($method->invoke($fixture->handler));
+
+        $response = $this->_decodeMoveItemsResponse(
+            $this->_readStream($fixture->output)
+        );
+        $this->assertSame(Horde_ActiveSync_Request_MoveItems::STATUS_INVALID_SRC, $response['status']);
+        $this->assertSame('169462', $response['srcMsgId']);
+    }
+
+    public function testMoveItemsReturnsInvalidSrcWhenDestinationFolderIsGone()
+    {
+        $fixture = $this->_createHandler();
+        $fixture->importer->expects($this->once())->method('init');
+        $fixture->importer->expects($this->once())
+            ->method('importMessageMove')
+            ->willThrowException(new Horde_ActiveSync_Exception_FolderGone('Folder not found in cache.'));
+
+        $this->_writeWbxml($fixture->input, function (Horde_ActiveSync_Wbxml_Encoder $encoder) {
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::MOVES);
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::MOVE);
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::SRCMSGID);
+            $encoder->content('169462');
+            $encoder->endTag();
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::SRCFLDID);
+            $encoder->content('F85953279');
+            $encoder->endTag();
+            $encoder->startTag(Horde_ActiveSync_Request_MoveItems::DSTFLDID);
+            $encoder->content('F37c56728');
+            $encoder->endTag();
+            $encoder->endTag();
+            $encoder->endTag();
+        });
+        $fixture->decoder->readWbxmlHeader();
+
+        $method = new ReflectionMethod(Horde_ActiveSync_Request_MoveItems::class, '_handle');
+        $method->setAccessible(true);
+        $this->assertTrue($method->invoke($fixture->handler));
+
+        $response = $this->_decodeMoveItemsResponse(
+            $this->_readStream($fixture->output)
+        );
+        $this->assertSame(Horde_ActiveSync_Request_MoveItems::STATUS_INVALID_SRC, $response['status']);
+    }
+
+    /**
+     * @return object{
+     *   handler: Horde_ActiveSync_Request_MoveItems,
+     *   input: resource,
+     *   output: resource,
+     *   importer: Horde_ActiveSync_Connector_Importer&\PHPUnit\Framework\MockObject\MockObject,
+     *   state: Horde_ActiveSync_State_Base&\PHPUnit\Framework\MockObject\MockObject
+     * }
+     */
+    protected function _createHandler(): object
+    {
+        $logger = new Horde_ActiveSync_Log_Logger(new Horde_Log_Handler_Null());
+        $input = fopen('php://memory', 'wb+');
+        $decoder = new Horde_ActiveSync_Wbxml_Decoder($input);
+
+        $output = fopen('php://memory', 'wb+');
+        $encoder = new Horde_ActiveSync_Wbxml_Encoder($output);
+
+        $driver = $this->createMock(Horde_ActiveSync_Driver_Base::class);
+        $state = $this->createMock(Horde_ActiveSync_State_Base::class);
+        $importer = $this->createMock(Horde_ActiveSync_Connector_Importer::class);
+
+        $request = new Horde_Controller_Request_Mock([
+            'get' => [
+                'Cmd' => 'MoveItems',
+                'DeviceId' => 'TESTDEVICE',
+            ],
+            'server' => [
+                'HTTP_MS_ASPROTOCOLVERSION' => Horde_ActiveSync::VERSION_SIXTEENONE,
+            ],
+        ]);
+
+        $server = $this->getMockBuilder(Horde_ActiveSync::class)
+            ->setConstructorArgs([$driver, $decoder, $encoder, $state, $request])
+            ->onlyMethods(['getImporter'])
+            ->getMock();
+        $server->method('getImporter')->willReturn($importer);
+
+        $device = new \Horde_ActiveSync_Device($state);
+        $device->id = 'TESTDEVICE';
+        $device->version = Horde_ActiveSync::VERSION_SIXTEENONE;
+        $deviceRef = new ReflectionProperty(Horde_ActiveSync::class, '_device');
+        $deviceRef->setAccessible(true);
+        $deviceRef->setValue(null, $device);
+
+        $handler = new Horde_ActiveSync_Request_MoveItems($server);
+        $handler->setLogger($logger);
+
+        return (object) [
+            'handler' => $handler,
+            'decoder' => $decoder,
+            'input' => $input,
+            'output' => $output,
+            'importer' => $importer,
+            'state' => $state,
+        ];
+    }
+
+    protected function _writeWbxml($stream, callable $writer): void
+    {
+        $encoder = new Horde_ActiveSync_Wbxml_Encoder($stream);
+        $encoder->startWBXML();
+        $writer($encoder);
+        rewind($stream);
+    }
+
+    /**
+     * @return array{status: ?int, srcMsgId: ?string}
+     */
+    protected function _decodeMoveItemsResponse(string $wbxml): array
+    {
+        $stream = fopen('php://memory', 'wb+');
+        fwrite($stream, $wbxml);
+        rewind($stream);
+
+        $decoder = new Horde_ActiveSync_Wbxml_Decoder($stream);
+        $decoder->readWbxmlHeader();
+        $decoder->getElementStartTag(Horde_ActiveSync_Request_MoveItems::MOVES);
+        $decoder->getElementStartTag(Horde_ActiveSync_Request_MoveItems::RESPONSE);
+
+        $response = [
+            'status' => null,
+            'srcMsgId' => null,
+        ];
+
+        while (($child = $decoder->peek()) !== false
+            && $child[Horde_ActiveSync_Wbxml::EN_TYPE] === Horde_ActiveSync_Wbxml::EN_TYPE_STARTTAG
+        ) {
+            $tag = $child[Horde_ActiveSync_Wbxml::EN_TAG];
+            $decoder->getElementStartTag($tag);
+            $content = $decoder->getElementContent();
+            $decoder->getElementEndTag();
+
+            if ($tag === Horde_ActiveSync_Request_MoveItems::STATUS) {
+                $response['status'] = (int) $content;
+            } elseif ($tag === Horde_ActiveSync_Request_MoveItems::SRCMSGID) {
+                $response['srcMsgId'] = $content;
+            }
+        }
+
+        $decoder->getElementEndTag();
+        $decoder->getElementEndTag();
+        fclose($stream);
+
+        return $response;
+    }
+
+    protected function _readStream($stream): string
+    {
+        rewind($stream);
+        return stream_get_contents($stream);
+    }
+}