/**
* Takes an UnencryptedMsg object and extracts only the data needed to encrypt the message,
* discarding data that is only used by Bitseal internally, such as the ID number.
*
* @param inputMsgData - The UnencryptedMsg object from which the data is to be extracted
* @return A byte[] containing the message data needed for encryption
*/
private byte[] constructMsgPayloadForEncryption(UnencryptedMsg unencMsg) {
byte[] msgDataForEncryption = null;
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
try {
outputStream.write(VarintEncoder.encode(unencMsg.getSenderAddressVersion()));
outputStream.write(VarintEncoder.encode(unencMsg.getSenderStreamNumber()));
outputStream.write(ByteUtils.intToBytes(unencMsg.getBehaviourBitfield()));
// If the public signing and public encryption keys have their leading 0x04 byte in place then
// we need to remove them
byte[] publicSigningKey = unencMsg.getPublicSigningKey();
if (publicSigningKey[0] == (byte) 4 && publicSigningKey.length == 65) {
publicSigningKey = ArrayCopier.copyOfRange(publicSigningKey, 1, publicSigningKey.length);
}
outputStream.write(publicSigningKey);
byte[] publicEncryptionKey = unencMsg.getPublicEncryptionKey();
if (publicEncryptionKey[0] == (byte) 4 && publicEncryptionKey.length == 65) {
publicEncryptionKey =
ArrayCopier.copyOfRange(publicEncryptionKey, 1, publicEncryptionKey.length);
}
outputStream.write(publicEncryptionKey);
if (unencMsg.getSenderAddressVersion()
>= 3) // The nonceTrialsPerByte and extraBytes fields are only included when the address
// version is >= 3
{
outputStream.write(VarintEncoder.encode(unencMsg.getNonceTrialsPerByte()));
outputStream.write(VarintEncoder.encode(unencMsg.getExtraBytes()));
}
outputStream.write(unencMsg.getDestinationRipe());
outputStream.write(VarintEncoder.encode(unencMsg.getEncoding()));
outputStream.write(VarintEncoder.encode(unencMsg.getMessageLength()));
outputStream.write(unencMsg.getMessage());
outputStream.write(VarintEncoder.encode(unencMsg.getAckLength()));
outputStream.write(unencMsg.getAckMsg());
outputStream.write(VarintEncoder.encode(unencMsg.getSignatureLength()));
outputStream.write(unencMsg.getSignature());
msgDataForEncryption = outputStream.toByteArray();
outputStream.close();
} catch (IOException e) {
throw new RuntimeException(
"IOException occurred in DataProcessor.constructMsgPayloadForEncryption()", e);
}
return msgDataForEncryption;
}
/**
* Calculates the acknowledgement Message for a given message. <br>
* <br>
* The process for this is as follows:<br>
* <br>
* 1) initialPayload = time || stream number || 32 bytes of random data<br>
* <br>
* 2) Do POW for the initialPayload<br>
* <br>
* 3) ackData = POWnonce || msgHeader || initialPayload<br>
* <br>
*
* @param message - The original plain text Message object, provided so that its status can be
* updated during the process
* @param ackData - A byte[] containing the 32 bytes of random data which is the acknowledgment
* data
* @param toStreamNumber - An int representing the stream number of the destination address of the
* message to be sent
* @param doPOW - A boolean indicating whether or not POW should be done for ack msgs generated
* during this process
* @param timeToLive - The 'time to live' value (in seconds) to be used in processing this message
* @return A byte[] containing the acknowledgement data for the message we wish to send
*/
private byte[] generateFullAckMessage(
Message message, byte[] ackData, int toStreamNumber, boolean doPOW, long timeToLive) {
// Get the fuzzed expiration time
long expirationTime = TimeUtils.getFuzzedExpirationTime(timeToLive);
// Encode the expiration time, object type, object version, and stream number values into byte
// form
byte[] expirationTimeBytes = ByteUtils.longToBytes((expirationTime));
byte[] objectTypeBytes = ByteUtils.intToBytes(OBJECT_TYPE_MSG);
byte[] objectVersionBytes = VarintEncoder.encode(OBJECT_VERSION_MSG);
byte[] streamNumberBytes = VarintEncoder.encode((long) toStreamNumber);
// Combine the time, object type, object version, stream number, and ack data values into a
// single byte[]
byte[] initialPayload =
ByteUtils.concatenateByteArrays(
expirationTimeBytes, objectTypeBytes, objectVersionBytes, streamNumberBytes, ackData);
// Create the payload for the ack msg
byte[] payload = new byte[0];
if (doPOW) {
// Update the status of this message displayed in the UI
String messageStatus = App.getContext().getString(R.string.message_status_doing_ack_pow);
MessageStatusHandler.updateMessageStatus(message, messageStatus);
// Do proof of work for the acknowledgement payload
Log.i(
TAG,
"About to do POW calculations for the acknowledgment payload of a msg that we are sending");
long powNonce =
new POWProcessor()
.doPOW(
initialPayload,
expirationTime,
POWProcessor.NETWORK_NONCE_TRIALS_PER_BYTE,
POWProcessor.NETWORK_EXTRA_BYTES);
byte[] powNonceBytes = ByteUtils.longToBytes(powNonce);
payload = ByteUtils.concatenateByteArrays(powNonceBytes, initialPayload);
} else {
payload = initialPayload;
}
byte[] headerData = new MessageProcessor().generateObjectHeader(payload);
byte[] fullAckMsg = ByteUtils.concatenateByteArrays(headerData, payload);
return fullAckMsg;
}
/**
* Takes a Msg and encodes it into a single byte[], in a way that is compatible with the way that
* PyBitmessage does. This payload can then be sent to a server to be disseminated across the
* network. The payload is stored as a Payload object.
*
* @param encMsg - A msg Object containing the message data used to create the payload.
* @param powDone - A boolean value indicating whether or not POW has been done for this message
* @param toPubkey - A Pubkey object containing the data for the Pubkey of the address that this
* message is being sent to
* @return A Payload object containing the message payload
*/
private Payload constructMsgPayloadForDissemination(
BMObject encMsg, boolean powDone, Pubkey toPubkey) {
// Create a new Payload object to hold the payload data
Payload msgPayload = new Payload();
msgPayload.setBelongsToMe(true);
msgPayload.setPOWDone(powDone);
msgPayload.setType(Payload.OBJECT_TYPE_MSG);
// Encode the POW nonce, expiration time, object type, object version, and stream number values
// into byte form
byte[] powNonceBytes = ByteUtils.longToBytes(encMsg.getPOWNonce());
byte[] expirationTimeBytes = ByteUtils.longToBytes(encMsg.getExpirationTime());
byte[] objectTypeBytes = ByteUtils.intToBytes(OBJECT_TYPE_MSG);
byte[] objectVersionBytes = VarintEncoder.encode(OBJECT_VERSION_MSG);
byte[] streamNumberBytes = VarintEncoder.encode(encMsg.getStreamNumber());
byte[] payload = null;
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
try {
if (powDone) {
outputStream.write(powNonceBytes);
}
outputStream.write(expirationTimeBytes);
outputStream.write(objectTypeBytes);
outputStream.write(objectVersionBytes);
outputStream.write(streamNumberBytes);
outputStream.write(encMsg.getPayload());
payload = outputStream.toByteArray();
outputStream.close();
} catch (IOException e) {
throw new RuntimeException(
"IOException occurred in DataProcessor.constructMsgPayloadForDissemination()", e);
}
msgPayload.setPayload(payload);
// Save the Payload object to the database
PayloadProvider payProv = PayloadProvider.get(App.getContext());
long msgPayloadId = payProv.addPayload(msgPayload);
// Finally, set the msg payload ID to the one generated by the SQLite database
msgPayload.setId(msgPayloadId);
return msgPayload;
}
/**
* Takes a Msg and constructs the payload needed to do POW for it.
*
* @param msg - The msg Object to construct the POW payload for
* @return The POW payload
*/
private byte[] constructMsgPayloadForPOW(BMObject msg) {
try {
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
outputStream.write(
ByteUtils.longToBytes(
msg.getExpirationTime())); // This conversion results in a byte[] of length 8, which
// is what we want
outputStream.write(ByteUtils.intToBytes(OBJECT_TYPE_MSG));
outputStream.write(VarintEncoder.encode(OBJECT_VERSION_MSG));
outputStream.write(VarintEncoder.encode(msg.getStreamNumber()));
outputStream.write(msg.getPayload());
return outputStream.toByteArray();
} catch (IOException e) {
throw new RuntimeException(
"IOException occurred in OutgoingMessageProcessor.constructMsgPayloadForPOW()", e);
}
}