/**
* Retrieve a DG file from the passport.
*
* @param dgTag Tag of the DG file to retrieve.
* @return The bytes of the DG file.
* @throws CardServiceException Gets thrown when there's a problem communicating with the
* passport.
* @throws IOException Gets thrown when there's a problem reading the file from the passport.
*/
public byte[] getDG(int dgTag) throws CardServiceException, IOException {
if (activateTerminal()) {
short dgFID = PassportFile.lookupFIDByTag(dgTag);
CardFileInputStream dgStream = _activePassportService.readFile(dgFID);
byte[] data = new byte[dgStream.getFileLength()];
int read = dgStream.read(data, 0, data.length);
if (read == data.length) return data;
}
return new byte[0];
}
/**
* Let the passport sign a message using the passports own private key.
*
* @param message The message to sign (can be any size)
* @return A signature, the response from the passport.
* @throws CardServiceException Gets thrown when there's a problem communicating with the
* passport.
* @throws NoSuchAlgorithmException Gets thrown when there's no SHA1 provider present.
*/
public byte[] signWithAA(byte[] message) throws CardServiceException, NoSuchAlgorithmException {
if (activateTerminal()) {
DG15File dg15 = new DG15File(_activePassportService.readFile(PassportService.EF_DG15));
PublicKey publicKey = dg15.getPublicKey();
MessageDigest digest = MessageDigest.getInstance("SHA1");
byte[] digestedMessage = digest.digest(message);
byte[] m2 = new byte[8];
System.arraycopy(digestedMessage, 0, m2, 0, m2.length);
return _activePassportService.sendAA(publicKey, m2);
}
return new byte[0];
}
