/// <summary>
/// Opens a FXP PASV connection between the source FTP Server and the destination FTP Server
/// </summary>
/// <param name="remoteClient">FtpClient instance of the destination FTP Server</param>
/// <returns>A data stream ready to be used</returns>
private FtpFxpSession OpenPassiveFXPConnection(FtpClient remoteClient)
{
FtpReply reply;
Match m;
FtpClient sourceClient = null;
FtpClient destinationClient = null;
if (EnableThreadSafeDataConnections)
{
sourceClient = CloneConnection();
sourceClient._AutoDispose = true;
sourceClient.CopyStateFlags(this);
sourceClient.Connect();
sourceClient.SetWorkingDirectory(GetWorkingDirectory());
}
else
{
sourceClient = this;
}
if (remoteClient.EnableThreadSafeDataConnections)
{
destinationClient = remoteClient.CloneConnection();
destinationClient._AutoDispose = true;
destinationClient.CopyStateFlags(remoteClient);
destinationClient.Connect();
destinationClient.SetWorkingDirectory(destinationClient.GetWorkingDirectory());
}
else
{
destinationClient = remoteClient;
}
sourceClient.SetDataType(sourceClient.FXPDataType);
destinationClient.SetDataType(destinationClient.FXPDataType);
// send PASV command to destination FTP server to get passive port to be used from source FTP server
if (!(reply = destinationClient.Execute("PASV")).Success)
{
throw new FtpCommandException(reply);
}
m = Regex.Match(reply.Message, @"(?<quad1>\d+)," + @"(?<quad2>\d+)," + @"(?<quad3>\d+)," + @"(?<quad4>\d+)," + @"(?<port1>\d+)," + @"(?<port2>\d+)");
if (!m.Success || m.Groups.Count != 7)
{
throw new FtpException("Malformed PASV response: " + reply.Message);
}
// Instruct source server to open a connection to the destination Server
if (!(reply = sourceClient.Execute($"PORT {m.Value}")).Success)
{
throw new FtpCommandException(reply);
}
return(new FtpFxpSession {
SourceServer = sourceClient, TargetServer = destinationClient
});
}
/// <summary>
/// Opens a FXP PASV connection between the source FTP Server and the destination FTP Server
/// </summary>
/// <param name="remoteClient">FtpClient instance of the destination FTP Server</param>
/// <returns>A data stream ready to be used</returns>
private FtpFxpSession OpenPassiveFXPConnection(FtpClient remoteClient, bool trackProgress)
{
FtpReply reply, reply2;
Match m;
FtpClient sourceClient = null;
FtpClient destinationClient = null;
FtpClient progressClient = null;
// create a new connection to the source FTP server if EnableThreadSafeDataConnections is set
if (EnableThreadSafeDataConnections)
{
sourceClient = CloneConnection();
sourceClient._AutoDispose = true;
sourceClient.CopyStateFlags(this);
sourceClient.Connect();
sourceClient.SetWorkingDirectory(GetWorkingDirectory());
}
else
{
sourceClient = this;
}
// create a new connection to the target FTP server if EnableThreadSafeDataConnections is set
if (remoteClient.EnableThreadSafeDataConnections)
{
destinationClient = remoteClient.CloneConnection();
destinationClient._AutoDispose = true;
destinationClient.CopyStateFlags(remoteClient);
destinationClient.Connect();
destinationClient.SetWorkingDirectory(remoteClient.GetWorkingDirectory());
}
else
{
destinationClient = remoteClient;
}
// create a new connection to the target FTP server to track progress
// if progress tracking is enabled during this FXP transfer
if (trackProgress)
{
progressClient = remoteClient.CloneConnection();
progressClient._AutoDispose = true;
progressClient.CopyStateFlags(remoteClient);
progressClient.Connect();
progressClient.SetWorkingDirectory(remoteClient.GetWorkingDirectory());
}
sourceClient.SetDataType(sourceClient.FXPDataType);
destinationClient.SetDataType(destinationClient.FXPDataType);
// send PASV/CPSV commands to destination FTP server to get passive port to be used from source FTP server
// first try with PASV - commonly supported by all servers
if (!(reply = destinationClient.Execute("PASV")).Success)
{
// then try with CPSV - known to be supported by glFTPd server
// FIXES #666 - glFTPd server - 435 Failed TLS negotiation on data channel
if (!(reply2 = destinationClient.Execute("CPSV")).Success)
{
throw new FtpCommandException(reply);
}
else
{
// use the CPSV response and extract the port from it
reply = reply2;
}
}
// extract port from response
m = Regex.Match(reply.Message, @"(?<quad1>\d+)," + @"(?<quad2>\d+)," + @"(?<quad3>\d+)," + @"(?<quad4>\d+)," + @"(?<port1>\d+)," + @"(?<port2>\d+)");
if (!m.Success || m.Groups.Count != 7)
{
throw new FtpException("Malformed PASV response: " + reply.Message);
}
// Instruct source server to open a connection to the destination Server
if (!(reply = sourceClient.Execute($"PORT {m.Value}")).Success)
{
throw new FtpCommandException(reply);
}
// the FXP session stores the active connections used for this FXP transfer
return(new FtpFxpSession {
SourceServer = sourceClient,
TargetServer = destinationClient,
ProgressServer = progressClient,
});
}