void CNetRender::ReceiveData(QTcpSocket *socket, sMessage *msg)
{
QDataStream socketReadStream(socket);
qint64 bytesAvailable = socket->bytesAvailable();
while(bytesAvailable > 0)
{
if (msg->command == netRender_NONE)
{
if (socket->bytesAvailable() < (qint64)((sizeof(msg->command) + sizeof(msg->id) + sizeof(msg->size))))
{
return;
}
// meta data available
socketReadStream >> msg->command;
socketReadStream >> msg->id;
socketReadStream >> msg->size;
}
bytesAvailable = socket->bytesAvailable();
if(msg->size > 0)
{
if (bytesAvailable < (qint64)(sizeof(quint16) + msg->size))
{
return;
}
// full payload available
char* buffer = new char[msg->size];
socketReadStream.readRawData(buffer, msg->size);
msg->payload.append(buffer, msg->size);
quint16 crcCalculated = qChecksum(buffer, msg->size);
quint16 crcReceived;
socketReadStream >> crcReceived;
delete[] buffer;
if(crcCalculated != crcReceived)
{
//ResetMessage(msg);
//socketReadStream.atEnd();
//socketReadStream.skipRawData(socket->bytesAvailable());
return;
}
msg->size = msg->payload.size();
}
ProcessData(socket, msg);
bytesAvailable = socket->bytesAvailable();
}
}
/*
Helper function for child process.
Parameter: socketFD - Socket file descriptor
Parameter: newSocketFD - New socket file descriptor
Parameter: buffer - Buffer string
*/
void childHelper(int socketFD, int newSocketFD, char buffer[]) {
// Instantiate variables
int temporaryResult;
long plainTextSize;
long keySize;
// Close socket and flush buffer
close(socketFD);
bzero(buffer, sizeof(buffer));
// Display to client the server type and re-Flush
socketWrite(newSocketFD, "enc_d");
bzero(buffer, sizeof(buffer));
// Fetch plainText size from client
temporaryResult = read(newSocketFD, &plainTextSize, sizeof(plainTextSize));
if (temporaryResult < 0) {
printf("Error - Socket Reading!\n");
}
// Set plainText length and send ACK response
long plainTextLength = ntohl(plainTextSize);
socketWrite(newSocketFD, "ACK");
// Allocate memory for plainText, begin plainText socket read stream, and terminate
char *plainText = malloc(sizeof(char) * (plainTextLength + 1));
long size = socketReadStream(newSocketFD, plainText, plainTextLength);
plainText[size] = '\0';
// Send ACK response and flush buffer for client key
socketWrite(newSocketFD, "ACK");
bzero(buffer, sizeof(buffer));
// Fetch client's key size
temporaryResult = read(newSocketFD, &keySize, sizeof(keySize));
if (temporaryResult < 0) {
printf("Error - Socket Reading!\n");
}
// Set key length and send ACK response
long keyLength = ntohl(keySize);
socketWrite(newSocketFD, "ACK");
// Allocate memory for client key and start read stream
char *key = malloc(sizeof(char) * (keyLength + 1));
size = socketReadStream(newSocketFD, key, keyLength);
key[size] = '\0';
// Send ACK response, encrypt plainText with client key, and send result
socketWrite(newSocketFD, "ACK");
char *cipherText = encrypt(key, plainText, strlen(plainText));
socketWrite(newSocketFD, cipherText);
// Cleanup
close(newSocketFD);
free(plainText);
free(key);
free(cipherText);
exit(0);
}
