[Wzdftpd-users] Valid user but no "331 User XX okay, need password.\r\n" from wzdftpd

[Jo M. <jo...@ma...>]

Hi,

I'm a complete newbie with wzdftpd and I'm not familiar with the
details FTP so please excuse me if this is a stupid question.  I've
tried to find related exchanges in the mailing list archive but drew a
blank.


Server  :   SMP Debian 3.2.68-1+deb7u6 ; AMD64
            wzdftpd 0.8.3-6.2

        Default Debian configuration, with auth as

        backend = /usr/lib/wzdftpd/backends/libwzd_plaintext.so > 124


If I connect to the server from another Debian machine using lftp, the
login works just fine.  Wireshark shows:

    lftp   ->  wzdftpd     File Transfer Protocol (FTP)
    client     server      USER jo\r\n
                           Request command: USER
                           Request arg: jo


    lftp   <-  wzdftpd     TCP Flags: 0x010 (ACK)
    client     server


    lftp   <-  wzdftpd     File Transfer Protocol (FTP)
    client     server      331 User jo okay, need password.\r\n
                           Response code: User name okay, need password (331)
                           Response arg: User jo okay, need password.


And all is well with the world.


However, when I try to make my wife's WanScan IP cammera connect I get
the following exchange:

    wanscan   ->  wzdftpd    File Transfer Protocol (FTP)
    camera        server     SYST\r\n
                             Request command: SYST


    wanscan   <-  wzdftpd    TCP Flags: 0x010 (ACK)
    camera        server


    wanscan   <-  wzdftpd    File Transfer Protocol (FTP)
    camera        server     530 Invalid login sequence\r\n
                             Response code: Not logged in (530)
                             Response arg: Invalid login sequence


    wanscan   ->  wzdftpd    File Transfer Protocol (FTP)
    camera        server     USER cjm\r\n
                             Request command: USER
                             Request arg: cjm


    wanscan   <-  wzdftpd    TCP Flags: 0x010 (ACK)
    camera        server


    wanscan   <-  wzdftpd    TCP Flags: 0x011 (FIN, ACK)
    camera        server


    wanscan   <-  wzdftpd    TCP Flags: 0x014 (RST, ACK)
    camera        server


    wanscan   ->  wzdftpd    TCP Flags: 0x011 (FIN, ACK)
    camera        server


    wanscan   <-  wzdftpd    TCP Flags: 0x004 (RST)       
    camera        server



The FTP server never seems to acknowledge that user cjm is ok and to 
proceed on to asking for a password.  Neither does the server seem to 
reject user cjm as being invalid.  In fact, user cjm is perfectly 
valid as can be seen when a different FTP client is used from the log 
extract below.

> 
> Nov 22 13:51:51 Sun Nov 22 13:51:51 2015 LOGIN: <client> (ip.addr) "cjm" "users" ""
> Nov 22 13:52:27 Sun Nov 22 13:52:27 2015 LOGOUT: <client> (ip.addr) "cjm" "users" ""
>


So now I'm a bit lost as to what to try next.  If I'm doing something 
wrong I'd be very grateful for any tips on how to correct my error, or 
perhaps there is a server config. change I could make to work around 
this issue.  Any advice, suggestions, ... gratefully received.


Best regards,

Jo.