When setting TLSRequired
to on
instead of off
in my proftp tls.conf
, I always get a
550 SSL/TLS required on the data channel
error when trying to connect. I tried it out with both filezilla and winscp and proftpd versions 1.3.3a
and 1.3.4a
This is my tls.conf:
<IfModule mod_tls.c>
TLSEngine on
TLSProtocol SSLv23 TLSv1
TLSRSACertificateFile /etc/ssl/private/cert.crt
TLSRSACertificateKeyFile /etc/ssl/private/cert.key
TLSVerifyClient off
TLSRequired on
</IfModule>
The error occurs after executing the FTP-LIST
command. This is a short excerpt from the debug log in filezilla:
Command: PASV
Trace: CFtpControlSocket::OnReceive()
Response: 227 Entering Passive Mode (78,46,187,75,208,71).
Trace: CFtpControlSocket::TransferParseResponse()
Trace: CFtpControlSocket::SendNextCommand()
Trace: CFtpControlSocket::TransferSend()
Command: LIST
Trace: CFtpControlSocket::OnReceive()
Response: 550 SSL/TLS required on the data channel
Trace: CFtpControlSocket::TransferParseResponse()
Trace: CFtpControlSocket::ResetOperation(2)
Trace: CControlSocket::ResetOperation(2)
Trace: CFtpControlSocket::ParseSubcommandResult(2)
Trace: CFtpControlSocket::ListSubcommandResult()
Trace: CFtpControlSocket::ResetOperation(2)
Trace: CControlSocket::ResetOperation(2)
Error: Directory listing could not be retrieved