On 9 December 2014 at 02:15, Andrew Kolbus <[email protected]> wrote: > I am using the TelnetClient from commons-net 3.3 in JDK 8. When I try to > receive xmodem data over a telnet session, some bytes do not make it through > to my code. > > Example: > The remote device sends this (confirmed using windows network monitor): > 01 01 FE [...] C0 00 FF FF FF 00 00 00 00 27 27 00 [...] (133 byte > xmodem-crc packet) > > However, from the telnet client, I get this: > 01 01 FE [...] C0 00 FF 00 00 00 27 27 00 [...] (130 bytes total) > > From what I have read, this is related to NVT. It looks like it is > converting [FF FF] to [FF] (removing one byte), and just outright removing > [FF 00] (removing another two bytes for a total of three).
Yes, that is what the RFC mandates: https://tools.ietf.org/html/rfc856#section-5 In binary mode, IAC (FF) is still required to be recognised. > I tried using telnetClient.addOptionHandler(new > SimpleOptionHandler(TelnetOption.BINARY, true, true, true, true));, but that > did not change the data I received. > > A sample of the code I used to discover the issue is attached. Is there a > way to get the TelnetClient to pass all data through? No, that would violate the RFC. https://tools.ietf.org/html/rfc856#section-5 > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
