Re: iptables ip_conntrack_ftp + proftpd TLS: PORT command not understood

[Patrick McHardy <kaber@trash.net>]

Filippo Zeus wrote:
> Considering ftp-control port is text based i've dumped with -A switch. I 
> hope it's ok
> 
> 03:05:59.149005 IP ***HIDDEN_IP***.21 > 151.80.2.63.55194: P 1:71(70) 
> ack 1 win 46
> 2.P.?......L.1...P....`..220 FTP Server ready. Please use FTP-TLS or 
> login wi
> 03:05:59.149078 IP 151.80.2.63.55194 > ***HIDDEN_IP***.21: . ack 71 win 
> 1024
> 2....1.....M.P.......+
> 03:05:59.149759 IP 151.80.2.63.55194 > ***HIDDEN_IP***.21: P 1:11(10) 
> ack 71 win 1024
> 2....1.....M.P.......AUTH TLS
> 
> 03:05:59.700919 IP ***HIDDEN_IP***.21 > 151.80.2.63.55194: . ack 11 win 46
> 2.P.?......M.1...P.......
> 03:05:59.700939 IP ***HIDDEN_IP***.21 > 151.80.2.63.55194: P 71:96(25) 
> ack 11 win 46
> 2.P.?......M.1...P...O...234 AUTH TLS successful
> 
> 03:05:59.701036 IP 151.80.2.63.55194 > ***HIDDEN_IP***.21: . ack 96 win 
> 1024
> 2....1.....M4P.......+
> 03:05:59.706276 IP 151.80.2.63.55194 > ***HIDDEN_IP***.21: P 11:95(84) 
> ack 96 win 1024
> 2....1.....M4P...L.......O...K..H;^w.i} ..\*.+....'b..]...5`.O....$.3.E.9
> 03:06:00.416441 IP ***HIDDEN_IP***.21 > 151.80.2.63.55194: P 
> 1516:1666(150) ack 95 win 46
> 2.P.?......R.1...P....[...)E..5O......tsp.+).)..W[H..u.)IP..&....XZr...~.<... 


Its a bit hard to read, but this looks like your client also
encrypts the control connection, which explains why FTP
conntrack doesn't work.