Function parseVersion

src/security/encryption-dict.ts:168–180

* Parse and validate the encryption version.

(dict: PdfDict)

 * Parse and validate the encryption version.
 */
function parseVersion(dict: PdfDict): EncryptionVersion {
  const version = dict.getNumber("V")?.value;

  if (version === undefined) {
    throw new EncryptionDictError("Missing /V (version) in encryption dictionary");
  }

  if (!isEncryptionVersion(version)) {
    throw new EncryptionDictError(`Unsupported encryption version: ${version}`);
  }

  return version;
}

/**
 * Parse and validate the encryption revision.