feat: add safe OneNote export serializers

2026-07-22 19:36:20 +02:00
parent f0f6e48188
commit ece969e269
7 changed files with 2328 additions and 0 deletions
--- a/src/onenote/export/naming.ts
+++ b/src/onenote/export/naming.ts
@@ -0,0 +1,158 @@
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this file,
+// You can obtain one at https://mozilla.org/MPL/2.0/.
+// SPDX-License-Identifier: MPL-2.0
+
+const WINDOWS_RESERVED = /^(?:CON|PRN|AUX|NUL|COM[1-9]|LPT[1-9])$/iu;
+const MAX_FILENAME_CODEPOINTS = 120;
+
+const ACTIVE_EXTENSIONS = new Set([
+  'app',
+  'application',
+  'bat',
+  'cjs',
+  'cmd',
+  'com',
+  'desktop',
+  'exe',
+  'hta',
+  'htm',
+  'html',
+  'jar',
+  'js',
+  'lnk',
+  'mjs',
+  'ps1',
+  'scr',
+  'svg',
+  'svgz',
+  'url',
+  'vbs',
+  'wasm',
+  'xhtml',
+  'xml',
+]);
+
+/** Convert untrusted display metadata into one safe ZIP path segment. */
+export function sanitizeExportFilename(
+  value: string | undefined,
+  fallback = 'untitled'
+): string {
+  let result = cleanFilenameSegment(value);
+  if (!result || result === '.' || result === '..') {
+    result = cleanFilenameSegment(fallback);
+  }
+  if (!result || result === '.' || result === '..') result = 'untitled';
+  if (WINDOWS_RESERVED.test(result.split('.')[0] ?? result)) {
+    result = `_${result}`;
+  }
+  result = truncateFilename(result, MAX_FILENAME_CODEPOINTS);
+  return result || 'untitled';
+}
+
+function cleanFilenameSegment(value: string | undefined): string {
+  const basename = (value ?? '').split(/[\\/]/u).at(-1) ?? '';
+  let result = '';
+  for (const character of basename.normalize('NFC')) {
+    const code = character.codePointAt(0)!;
+    if (isControlOrDirectional(code)) continue;
+    result += '<>:"/\\|?*'.includes(character) ? '_' : character;
+  }
+  result = result
+    .replace(/\s+/gu, ' ')
+    .replace(/\.{2,}/gu, '.')
+    .replace(/^[ .]+|[ .]+$/gu, '');
+  return result;
+}
+
+export function normalizeExportExtension(
+  value: string | undefined
+): string | undefined {
+  const extension = value
+    ?.split('\0')
+    .join('')
+    .trim()
+    .replace(/^\.+/u, '')
+    .toLowerCase();
+  return extension && /^[a-z0-9][a-z0-9._+-]{0,15}$/u.test(extension)
+    ? extension
+    : undefined;
+}
+
+/** Make browser/script/executable attachment suffixes download-inert. */
+export function neutralizeActiveExtension(filename: string): {
+  filename: string;
+  neutralized: boolean;
+} {
+  const extension = filenameExtension(filename);
+  if (!extension || !ACTIVE_EXTENSIONS.has(extension)) {
+    return { filename, neutralized: false };
+  }
+  return { filename: `${filename}.bin`, neutralized: true };
+}
+
+export function forceFilenameExtension(
+  filename: string,
+  extension: string
+): string {
+  const safeExtension = normalizeExportExtension(extension) ?? 'bin';
+  const index = filename.lastIndexOf('.');
+  const stem = index > 0 ? filename.slice(0, index) : filename;
+  return truncateFilename(`${stem}.${safeExtension}`, MAX_FILENAME_CODEPOINTS);
+}
+
+export function filenameExtension(filename: string): string | undefined {
+  const index = filename.lastIndexOf('.');
+  return index > 0 && index < filename.length - 1
+    ? filename.slice(index + 1).toLowerCase()
+    : undefined;
+}
+
+export class SafeExportNameAllocator {
+  private readonly used = new Set<string>();
+
+  allocate(value: string | undefined, fallback = 'untitled'): string {
+    const safe = sanitizeExportFilename(value, fallback);
+    if (this.reserve(safe)) return safe;
+    const extension = filenameExtension(safe);
+    const stem = extension ? safe.slice(0, -(extension.length + 1)) : safe;
+    for (let suffix = 2; suffix < 1_000_000; suffix += 1) {
+      const candidate = truncateFilename(
+        `${stem}-${suffix}${extension ? `.${extension}` : ''}`,
+        MAX_FILENAME_CODEPOINTS
+      );
+      if (this.reserve(candidate)) return candidate;
+    }
+    throw new Error('Could not allocate a unique export filename');
+  }
+
+  private reserve(value: string): boolean {
+    const key = value.toLocaleLowerCase('en-US');
+    if (this.used.has(key)) return false;
+    this.used.add(key);
+    return true;
+  }
+}
+
+function truncateFilename(value: string, maxCodepoints: number): string {
+  const characters = [...value];
+  if (characters.length <= maxCodepoints) return value;
+  const extension = filenameExtension(value);
+  const suffix =
+    extension && [...extension].length <= 16 ? `.${extension}` : '';
+  const suffixLength = [...suffix].length;
+  return `${characters.slice(0, Math.max(1, maxCodepoints - suffixLength)).join('')}${suffix}`.replace(
+    /[ .]+$/gu,
+    ''
+  );
+}
+
+function isControlOrDirectional(code: number): boolean {
+  return (
+    code <= 0x1f ||
+    (code >= 0x7f && code <= 0x9f) ||
+    (code >= 0x202a && code <= 0x202e) ||
+    (code >= 0x2066 && code <= 0x2069) ||
+    code === 0xfeff
+  );
+}