/**
* Encodes the provided message with the private key and pass phrase set in configuration
*
* @param message Message to encode
* @return Encoded message
* @throws LRException SIGNING_FAILED if the document cannot be signed, NO_KEY if the key cannot
* be obtained
*/
private String signEnvelopeData(String message) throws LRException {
// Get an InputStream for the private key
InputStream privateKeyStream = getPrivateKeyStream(privateKey);
// Get an OutputStream for the result
ByteArrayOutputStream result = new ByteArrayOutputStream();
ArmoredOutputStream aOut = new ArmoredOutputStream(result);
// Get the pass phrase
char[] privateKeyPassword = passPhrase.toCharArray();
try {
// Get the private key from the InputStream
PGPSecretKey sk = readSecretKey(privateKeyStream);
PGPPrivateKey pk = sk.extractPrivateKey(privateKeyPassword, "BC");
PGPSignatureGenerator pgp =
new PGPSignatureGenerator(sk.getPublicKey().getAlgorithm(), PGPUtil.SHA256, "BC");
PGPSignatureSubpacketGenerator spGen = new PGPSignatureSubpacketGenerator();
// Clear sign the message
java.util.Iterator it = sk.getPublicKey().getUserIDs();
if (it.hasNext()) {
spGen.setSignerUserID(false, (String) it.next());
pgp.setHashedSubpackets(spGen.generate());
}
aOut.beginClearText(PGPUtil.SHA256);
pgp.initSign(PGPSignature.CANONICAL_TEXT_DOCUMENT, pk);
byte[] msg = message.getBytes();
pgp.update(msg, 0, msg.length);
aOut.write(msg, 0, msg.length);
BCPGOutputStream bOut = new BCPGOutputStream(aOut);
aOut.endClearText();
pgp.generate().encode(bOut);
String strResult = result.toString("utf8");
return strResult;
} catch (Exception e) {
throw new LRException(LRException.SIGNING_FAILED);
} finally {
try {
if (privateKeyStream != null) {
privateKeyStream.close();
}
aOut.close();
result.close();
} catch (IOException e) {
// Could not close the streams
}
}
}
/**
* Reads private key from the provided InputStream
*
* @param input InputStream of the private key
* @return PGPSecretKey
* @throws LRException NO_KEY error if the key cannot be obtained from the input stream
*/
private PGPSecretKey readSecretKey(InputStream input) throws LRException {
PGPSecretKeyRingCollection pgpSec;
try {
pgpSec = new PGPSecretKeyRingCollection(PGPUtil.getDecoderStream(input));
} catch (Exception e) {
throw new LRException(LRException.NO_KEY);
}
java.util.Iterator keyRingIter = pgpSec.getKeyRings();
while (keyRingIter.hasNext()) {
PGPSecretKeyRing keyRing = (PGPSecretKeyRing) keyRingIter.next();
java.util.Iterator keyIter = keyRing.getSecretKeys();
while (keyIter.hasNext()) {
PGPSecretKey key = (PGPSecretKey) keyIter.next();
if (key.isSigningKey()) {
return key;
}
}
}
throw new LRException(LRException.NO_KEY);
}
