Harden backup and download token flows

src/handlers/attachments.ts

@@ -439,17 +439,16 @@ export async function handlePublicDownloadAttachment(
   }
 
   const path = getAttachmentObjectKey(cipherId, attachmentId);
-  const object = await getBlobObject(env, path);
-
-  if (!object) {
-    return errorResponse('Attachment file not found', 404);
-  }
-
   const firstUse = await storage.consumeAttachmentDownloadToken(claims.jti, claims.exp);
   if (!firstUse) {
     return errorResponse('Invalid or expired token', 401);
   }
 
+  const object = await getBlobObject(env, path);
+  if (!object) {
+    return errorResponse('Attachment file not found', 404);
+  }
+
   return new Response(object.body, {
     headers: {
       'Content-Type': sanitizeDownloadContentType(object.contentType),

src/handlers/backup.ts

@@ -1062,12 +1062,21 @@ export async function handleDownloadAdminRemoteBackup(request: Request, env: Env
 export async function handleInspectAdminRemoteBackup(request: Request, env: Env, actorUser: User): Promise<Response> {
   if (!isAdmin(actorUser)) return errorResponse('Forbidden', 403);
 
+  let body: { destinationId?: string; path?: string; masterPasswordHash?: string };
+  try {
+    body = await request.json<{ destinationId?: string; path?: string; masterPasswordHash?: string }>();
+  } catch {
+    return errorResponse('Remote backup integrity payload is invalid', 400);
+  }
+
+  const verificationError = await requireBackupUserVerification(actorUser, String(body.masterPasswordHash || ''), env);
+  if (verificationError) return verificationError;
+
   const storage = new StorageService(env.DB);
   try {
     const settings = await loadBackupSettings(storage, env, 'UTC');
-    const url = new URL(request.url);
-    const path = ensureRemoteRestoreCandidate(url.searchParams.get('path') || '');
-    const destination = requireBackupDestination(settings, url.searchParams.get('destinationId') || null);
+    const path = ensureRemoteRestoreCandidate(String(body.path || ''));
+    const destination = requireBackupDestination(settings, body.destinationId || null);
     const remoteFile = await downloadRemoteBackupFile(destination, path);
     const integrity = await inspectBackupArchiveFileNameChecksum(remoteFile.bytes, remoteFile.fileName || path);
     return jsonResponse({

src/handlers/sends-public.ts

@@ -300,17 +300,17 @@ export async function handleDownloadSendFile(
     return errorResponse(SEND_INACCESSIBLE_MSG, 404);
   }
 
+  const firstUse = await storage.consumeAttachmentDownloadToken(`send:${claims.jti}`, claims.exp);
+  if (!firstUse) {
+    return errorResponse('Invalid or expired token', 401);
+  }
+
   const object = await getBlobObject(env, getSendFileObjectKey(sendId, fileId));
   if (!object) {
     return errorResponse('Send file not found', 404);
   }
   const fileName = typeof data.fileName === 'string' ? data.fileName : fileId;
 
-  const firstUse = await storage.consumeAttachmentDownloadToken(`send:${claims.jti}`, claims.exp);
-  if (!firstUse) {
-    return errorResponse('Invalid or expired token', 401);
-  }
-
   return new Response(object.body, {
     headers: {
       'Content-Type': sanitizeDownloadContentType(object.contentType),

src/router-admin-backup.ts

@@ -54,7 +54,7 @@ export async function handleAdminBackupRoute(
     return handleDownloadAdminRemoteBackup(request, env, actorUser);
   }
 
-  if (path === '/api/admin/backup/remote/integrity' && method === 'GET') {
+  if (path === '/api/admin/backup/remote/integrity' && method === 'POST') {
     return handleInspectAdminRemoteBackup(request, env, actorUser);
   }
 

webapp/src/App.tsx

@@ -2120,7 +2120,10 @@ export default function App() {
       const hash = await deriveCurrentMasterPasswordHash(masterPassword);
       return backupActions.downloadRemoteBackup(hash, destinationId, path, onProgress);
     },
-    onInspectRemoteBackup: backupActions.inspectRemoteBackup,
+    onInspectRemoteBackup: async (masterPassword: string, destinationId: string, path: string) => {
+      const hash = await deriveCurrentMasterPasswordHash(masterPassword);
+      return backupActions.inspectRemoteBackup(hash, destinationId, path);
+    },
     onDeleteRemoteBackup: async (masterPassword: string, destinationId: string, path: string) => {
       const hash = await deriveCurrentMasterPasswordHash(masterPassword);
       return backupActions.deleteRemoteBackup(hash, destinationId, path);

webapp/src/components/AppMainRoutes.tsx

@@ -168,7 +168,7 @@ export interface AppMainRoutesProps {
   onRunRemoteBackup: (masterPassword: string, destinationId?: string | null) => Promise<AdminBackupRunResponse>;
   onListRemoteBackups: (destinationId: string, path: string) => Promise<RemoteBackupBrowserResponse>;
   onDownloadRemoteBackup: (masterPassword: string, destinationId: string, path: string, onProgress?: (percent: number | null) => void) => Promise<void>;
-  onInspectRemoteBackup: (destinationId: string, path: string) => Promise<{ object: 'backup-remote-integrity'; destinationId: string; path: string; fileName: string; integrity: { hasChecksumPrefix: boolean; expectedPrefix: string | null; actualPrefix: string; matches: boolean } }>;
+  onInspectRemoteBackup: (masterPassword: string, destinationId: string, path: string) => Promise<{ object: 'backup-remote-integrity'; destinationId: string; path: string; fileName: string; integrity: { hasChecksumPrefix: boolean; expectedPrefix: string | null; actualPrefix: string; matches: boolean } }>;
   onDeleteRemoteBackup: (masterPassword: string, destinationId: string, path: string) => Promise<void>;
   onRestoreRemoteBackup: (masterPassword: string, destinationId: string, path: string, replaceExisting?: boolean) => Promise<AdminBackupImportResponse>;
   onRestoreRemoteBackupAllowingChecksumMismatch: (masterPassword: string, destinationId: string, path: string, replaceExisting?: boolean) => Promise<AdminBackupImportResponse>;

webapp/src/components/BackupCenterPage.tsx

@@ -42,7 +42,7 @@ interface BackupCenterPageProps {
   onRunRemoteBackup: (masterPassword: string, destinationId?: string | null) => Promise<AdminBackupRunResponse>;
   onListRemoteBackups: (destinationId: string, path: string) => Promise<RemoteBackupBrowserResponse>;
   onDownloadRemoteBackup: (masterPassword: string, destinationId: string, path: string, onProgress?: (percent: number | null) => void) => Promise<void>;
-  onInspectRemoteBackup: (destinationId: string, path: string) => Promise<{ object: 'backup-remote-integrity'; destinationId: string; path: string; fileName: string; integrity: BackupFileIntegrityCheckResult }>;
+  onInspectRemoteBackup: (masterPassword: string, destinationId: string, path: string) => Promise<{ object: 'backup-remote-integrity'; destinationId: string; path: string; fileName: string; integrity: BackupFileIntegrityCheckResult }>;
   onDeleteRemoteBackup: (masterPassword: string, destinationId: string, path: string) => Promise<void>;
   onRestoreRemoteBackup: (masterPassword: string, destinationId: string, path: string, replaceExisting?: boolean) => Promise<AdminBackupImportResponse>;
   onRestoreRemoteBackupAllowingChecksumMismatch: (masterPassword: string, destinationId: string, path: string, replaceExisting?: boolean) => Promise<AdminBackupImportResponse>;
@@ -492,8 +492,8 @@ export default function BackupCenterPage(props: BackupCenterPageProps) {
     return verifyBackupFileIntegrity(bytes, file.name || '');
   }
 
-  async function inspectRemoteBackupFile(destinationId: string, path: string): Promise<PendingRestoreIntegrity> {
-    const payload = await props.onInspectRemoteBackup(destinationId, path);
+  async function inspectRemoteBackupFile(masterPassword: string, destinationId: string, path: string): Promise<PendingRestoreIntegrity> {
+    const payload = await props.onInspectRemoteBackup(masterPassword, destinationId, path);
     return {
       source: 'remote',
       path,
@@ -800,19 +800,7 @@ export default function BackupCenterPage(props: BackupCenterPageProps) {
     if (!savedSelectedDestination) return;
     setLocalError('');
     resetPendingIntegrityWarning();
-    try {
-      const integrity = await inspectRemoteBackupFile(savedSelectedDestination.id, path);
-      if (!integrity.result.matches) {
-        setPendingRestoreIntegrity(integrity);
-        setConfirmIntegrityWarningOpen(true);
-        return;
-      }
-      await runRemoteRestore(path, false, false, integrity.result);
-    } catch (error) {
-      const message = error instanceof Error ? error.message : t('txt_backup_integrity_check_failed');
-      setLocalError(message);
-      props.onNotify('error', message);
-    }
+    await runRemoteRestore(path, false);
   }
 
   async function runRemoteRestore(
@@ -846,7 +834,23 @@ export default function BackupCenterPage(props: BackupCenterPageProps) {
     setRestoringRemotePath(path);
     setLocalError('');
     try {
-      const integrity = knownIntegrity ? { result: knownIntegrity } : await inspectRemoteBackupFile(savedSelectedDestination.id, path);
+      const integrity = knownIntegrity
+        ? { result: knownIntegrity }
+        : await inspectRemoteBackupFile(masterPassword, savedSelectedDestination.id, path);
+      if (!allowChecksumMismatch && !integrity.result.matches) {
+        setPendingRestoreIntegrity(
+          'source' in integrity
+            ? integrity
+            : {
+              source: 'remote',
+              path,
+              fileName: path.split('/').pop() || path,
+              result: integrity.result,
+            }
+        );
+        setConfirmIntegrityWarningOpen(true);
+        return true;
+      }
       startRestoreProgress('backup-restore', path.split('/').pop() || path, {
         source: 'remote',
         delayMs: replaceExisting ? 480 : 1400,

webapp/src/hooks/useBackupActions.ts

@@ -82,8 +82,8 @@ export default function useBackupActions(options: UseBackupActionsOptions) {
         downloadBytesAsFile(payload.bytes, payload.fileName, payload.mimeType);
       },
 
-      async inspectRemoteBackup(destinationId: string, path: string) {
-        return inspectRemoteBackupIntegrity(authedFetch, destinationId, path);
+      async inspectRemoteBackup(masterPasswordHash: string, destinationId: string, path: string) {
+        return inspectRemoteBackupIntegrity(authedFetch, masterPasswordHash, destinationId, path);
       },
 
       async deleteRemoteBackup(masterPasswordHash: string, destinationId: string, path: string) {

webapp/src/lib/api/backup.ts

@@ -420,13 +420,15 @@ export async function deleteRemoteBackup(
 
 export async function inspectRemoteBackupIntegrity(
   authedFetch: AuthedFetch,
+  masterPasswordHash: string,
   destinationId: string,
   path: string
 ): Promise<RemoteBackupIntegrityResponse> {
-  const params = new URLSearchParams();
-  params.set('destinationId', destinationId);
-  params.set('path', path);
-  const resp = await authedFetch(`/api/admin/backup/remote/integrity?${params.toString()}`, { method: 'GET' });
+  const resp = await authedFetch('/api/admin/backup/remote/integrity', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ destinationId, path, masterPasswordHash }),
+  });
   if (!resp.ok) throw new Error(await parseErrorMessage(resp, t('txt_backup_remote_download_failed')));
   const body = await parseJson<RemoteBackupIntegrityResponse>(resp);
   if (!body?.integrity || !body?.fileName) throw new Error(t('txt_backup_remote_invalid_response'));

webapp/src/lib/demo.ts

@@ -1201,7 +1201,7 @@ export function createDemoMainRoutesProps(base: AppMainRoutesProps, notify: Noti
     onDownloadRemoteBackup: async (_masterPassword: string, _destinationId: string, _path: string, _onProgress?: (percent: number | null) => void) => {
       notify('success', t('txt_demo_download_prepared'));
     },
-    onInspectRemoteBackup: async (_destinationId: string, path: string) => ({
+    onInspectRemoteBackup: async (_masterPassword: string, _destinationId: string, path: string) => ({
       object: 'backup-remote-integrity',
       destinationId: _destinationId,
       path,