public static byte[] Serialize(this ITftpPacket packet)
{
MemoryStream bytes = new MemoryStream();
bytes.Write(EndianBitConverter.Big.GetBytes((ushort)packet.Op), 0, sizeof(ushort));
switch (packet.Op)
{
case TftpOperation.ReadRequest:
RrqPacket rrq = (RrqPacket)packet;
StringToNetascii(rrq.FileName, bytes);
StringToNetascii(rrq.Mode.ToString(), bytes);
break;
case TftpOperation.WriteRequest:
WrqPacket wrq = (WrqPacket)packet;
StringToNetascii(wrq.FileName, bytes);
StringToNetascii(wrq.Mode.ToString(), bytes);
break;
case TftpOperation.Data:
DataPacket data = (DataPacket)packet;
bytes.Write(EndianBitConverter.Big.GetBytes((ushort)data.BlockNumber), 0, sizeof(ushort));
bytes.Write(data.Data, 0, data.Data.Length);
break;
case TftpOperation.Ack:
AckPacket ack = (AckPacket)packet;
bytes.Write(EndianBitConverter.Big.GetBytes((ushort)ack.BlockNumber), 0, sizeof(ushort));
break;
case TftpOperation.Error:
ErrorPacket error = (ErrorPacket)packet;
bytes.Write(EndianBitConverter.Big.GetBytes((ushort)error.Error), 0, sizeof(ushort));
StringToNetascii(error.Message, bytes);
break;
default:
throw new Exception("Operation not recognized.");
}
return(bytes.ToArray());
}
public void Write(IPEndPoint server, string fileName, string inputPath, CancellationToken cancellationToken)
{
Console.WriteLine("Writing local file '{0}' to file '{1}' on server {2}", inputPath, fileName, server);
// Read the file from the local file system.
byte[] file = File.ReadAllBytes(inputPath);
// Create a connection with the server.
IPEndPoint receivedFromEP = new IPEndPoint(IPAddress.Any, 0);
using (RemoteEndPointReservation clientReservation = new RemoteEndPointReservation(server))
using (TftpConnection connection = new TftpConnection())
{
RemoteEndPointReservation remoteEPReservation = null;
try
{
// Read the file contents to the remote endpoint in chunks.
ushort currentBlockNumber = 0;
int currentFileIndex = 0;
bool done = false;
while (!done)
{
Func <ITftpPacket, bool> receiveFilter = (ITftpPacket packet) =>
{
if (packet.Op == TftpOperation.Ack)
{
AckPacket ack = (AckPacket)packet;
if (ack.BlockNumber == currentBlockNumber)
{
Console.WriteLine("ACK received for block {0}", ack.BlockNumber);
return(true);
}
else
{
Console.WriteLine("Incorrect ACK block number {0}", ack.BlockNumber);
}
}
else
{
Console.WriteLine("Incorrect operation. Expected ACK.");
}
return(false);
};
ITftpPacket sendPacket;
// To initialize the transfer, send WRQ and wait for an ACK of block 0.
if (currentBlockNumber == 0)
{
Console.WriteLine("Sending WRQ");
// NOTE: the server only supports octet mode by design.
sendPacket = new WrqPacket(fileName, TftpMode.octet);
IPEndPoint remoteEP;
connection.SendAndWaitForResponse(sendPacket, server, receiveFilter, out remoteEP, cancellationToken);
remoteEPReservation = new RemoteEndPointReservation(remoteEP);
connection.Connect(remoteEP);
}
else
{
// Extract the current block from the file contents and put it in a DATA packet.
Console.WriteLine("Sending block {0}", currentBlockNumber);
int remainingBytes = file.Length - currentFileIndex;
int blockSize;
if (remainingBytes < DataPacket.MaxBlockSize)
{
blockSize = remainingBytes;
done = true;
}
else
{
blockSize = DataPacket.MaxBlockSize;
}
byte[] block = new byte[blockSize];
Buffer.BlockCopy(file, currentFileIndex, block, 0, blockSize);
currentFileIndex += block.Length;
sendPacket = new DataPacket(blockNumber: currentBlockNumber, data: block);
// Send the DATA packet and wait for the corresponding ACK.
connection.SendAndWaitForResponse(sendPacket, receiveFilter, cancellationToken);
}
// Move to the next block.
currentBlockNumber++;
}
}
finally
{
if (remoteEPReservation != null)
{
remoteEPReservation.Dispose();
}
}
}
}
