fix: disable encrypted pdfs (#1130)

## Description

Currently if you complete a pending encrypted document, it will prevent
the document from being sealed due to the systems inability to decrypt
it.

This PR disables uploading any documents that cannot be loaded as a
temporary measure.

**Note**
This is a client side only check

## Changes Made

- Disable uploading documents that cannot be parsed
- Refactor putFile to putDocumentFile
- Add a flag as a backup incase something goes wrong

packages/lib/constants/feature-flags.ts

@@ -21,6 +21,7 @@ export const FEATURE_FLAG_POLL_INTERVAL = 30000;
  * Does not take any person or group properties into account.
  */
 export const LOCAL_FEATURE_FLAGS: Record<string, boolean> = {
+  app_allow_encrypted_documents: false,
   app_billing: NEXT_PUBLIC_FEATURE_BILLING_ENABLED() === 'true',
   app_document_page_view_history_sheet: false,
   app_passkey: WEBAPP_BASE_URL === 'http://localhost:3000', // Temp feature flag.

packages/lib/server-only/document/seal-document.ts

@@ -14,7 +14,7 @@ import { signPdf } from '@documenso/signing';
 
 import type { RequestMetadata } from '../../universal/extract-request-metadata';
 import { getFile } from '../../universal/upload/get-file';
-import { putFile } from '../../universal/upload/put-file';
+import { putPdfFile } from '../../universal/upload/put-file';
 import { getCertificatePdf } from '../htmltopdf/get-certificate-pdf';
 import { flattenAnnotations } from '../pdf/flatten-annotations';
 import { insertFieldInPDF } from '../pdf/insert-field-in-pdf';
@@ -122,7 +122,7 @@ export const sealDocument = async ({
 
   const { name, ext } = path.parse(document.title);
 
-  const { data: newData } = await putFile({
+  const { data: newData } = await putPdfFile({
     name: `${name}_signed${ext}`,
     type: 'application/pdf',
     arrayBuffer: async () => Promise.resolve(pdfBuffer),

packages/lib/server-only/document/send-document.tsx

@@ -8,6 +8,7 @@ import { sealDocument } from '@documenso/lib/server-only/document/seal-document'
 import { updateDocument } from '@documenso/lib/server-only/document/update-document';
 import { DOCUMENT_AUDIT_LOG_TYPE } from '@documenso/lib/types/document-audit-logs';
 import type { RequestMetadata } from '@documenso/lib/universal/extract-request-metadata';
+import { putPdfFile } from '@documenso/lib/universal/upload/put-file';
 import { createDocumentAuditLogData } from '@documenso/lib/utils/document-audit-logs';
 import { renderCustomEmailTemplate } from '@documenso/lib/utils/render-custom-email-template';
 import { prisma } from '@documenso/prisma';
@@ -20,7 +21,6 @@ import {
   RECIPIENT_ROLE_TO_EMAIL_TYPE,
 } from '../../constants/recipient-roles';
 import { getFile } from '../../universal/upload/get-file';
-import { putFile } from '../../universal/upload/put-file';
 import { insertFormValuesInPdf } from '../pdf/insert-form-values-in-pdf';
 import { triggerWebhook } from '../webhooks/trigger/trigger-webhook';
 
@@ -102,7 +102,7 @@ export const sendDocument = async ({
       formValues: document.formValues as Record<string, string | number | boolean>,
     });
 
-    const newDocumentData = await putFile({
+    const newDocumentData = await putPdfFile({
       name: document.title,
       type: 'application/pdf',
       arrayBuffer: async () => Promise.resolve(prefilled),

packages/lib/universal/upload/put-file.ts

@@ -1,9 +1,12 @@
 import { base64 } from '@scure/base';
 import { env } from 'next-runtime-env';
+import { PDFDocument } from 'pdf-lib';
 import { match } from 'ts-pattern';
 
+import { getFlag } from '@documenso/lib/universal/get-feature-flag';
 import { DocumentDataType } from '@documenso/prisma/client';
 
+import { AppError } from '../../errors/app-error';
 import { createDocumentData } from '../../server-only/document-data/create-document-data';
 
 type File = {
@@ -12,14 +15,38 @@ type File = {
   arrayBuffer: () => Promise<ArrayBuffer>;
 };
 
+/**
+ * Uploads a document file to the appropriate storage location and creates
+ * a document data record.
+ */
+export const putPdfFile = async (file: File) => {
+  const isEncryptedDocumentsAllowed = await getFlag('app_allow_encrypted_documents').catch(
+    () => false,
+  );
+
+  // This will prevent uploading encrypted PDFs or anything that can't be opened.
+  if (!isEncryptedDocumentsAllowed) {
+    await PDFDocument.load(await file.arrayBuffer()).catch((e) => {
+      console.error(`PDF upload parse error: ${e.message}`);
+
+      throw new AppError('INVALID_DOCUMENT_FILE');
+    });
+  }
+
+  const { type, data } = await putFile(file);
+
+  return await createDocumentData({ type, data });
+};
+
+/**
+ * Uploads a file to the appropriate storage location.
+ */
 export const putFile = async (file: File) => {
   const NEXT_PUBLIC_UPLOAD_TRANSPORT = env('NEXT_PUBLIC_UPLOAD_TRANSPORT');
 
-  const { type, data } = await match(NEXT_PUBLIC_UPLOAD_TRANSPORT)
+  return await match(NEXT_PUBLIC_UPLOAD_TRANSPORT)
     .with('s3', async () => putFileInS3(file))
     .otherwise(async () => putFileInDatabase(file));
-
-  return await createDocumentData({ type, data });
 };
 
 const putFileInDatabase = async (file: File) => {