public static Workbook decryptWorkbook(InputStream inputStream, String password)
throws IOException, GeneralSecurityException {
POIFSFileSystem fs = new POIFSFileSystem(inputStream);
EncryptionInfo info = new EncryptionInfo(fs);
Decryptor d = Decryptor.getInstance(info);
d.verifyPassword(password);
InputStream dataStream = d.getDataStream(fs);
XSSFWorkbook workbook = new XSSFWorkbook(dataStream);
return workbook;
}
/** Creates a Workbook from the given NPOIFSFileSystem, which may be password protected */
private static Workbook create(NPOIFSFileSystem fs, String password)
throws IOException, InvalidFormatException {
DirectoryNode root = fs.getRoot();
// Encrypted OOXML files go inside OLE2 containers, is this one?
if (root.hasEntry(Decryptor.DEFAULT_POIFS_ENTRY)) {
EncryptionInfo info = new EncryptionInfo(fs);
Decryptor d = Decryptor.getInstance(info);
boolean passwordCorrect = false;
InputStream stream = null;
try {
if (password != null && d.verifyPassword(password)) {
passwordCorrect = true;
}
if (!passwordCorrect && d.verifyPassword(Decryptor.DEFAULT_PASSWORD)) {
passwordCorrect = true;
}
if (passwordCorrect) {
stream = d.getDataStream(root);
}
} catch (GeneralSecurityException e) {
throw new IOException(e);
}
if (!passwordCorrect) {
if (password != null) throw new EncryptedDocumentException("Password incorrect");
else
throw new EncryptedDocumentException(
"The supplied spreadsheet is protected, but no password was supplied");
}
OPCPackage pkg = OPCPackage.open(stream);
return create(pkg);
}
// If we get here, it isn't an encrypted XLSX file
// So, treat it as a regular HSSF XLS one
if (password != null) {
Biff8EncryptionKey.setCurrentUserPassword(password);
}
Workbook wb = new HSSFWorkbook(root, true);
Biff8EncryptionKey.setCurrentUserPassword(null);
return wb;
}
