proftpd tls internal connection works, external connection fails

Question

I am trying to secure my proftpd server but I cannot see what I do wrong.

My tls.conf

<IfModule mod_tls.c>
    TLSEngine                               on
TLSLog                                  /var/log/proftpd/tls.log
TLSProtocol                             TLSv1
TLSCipherSuite AES128+EECDH:AES128+EDH
TLSOptions                 NoCertRequest AllowClientRenegotiations

TLSRSACertificateFile                   /etc/ssl/certs/mailserver.pem
TLSRSACertificateKeyFile                /etc/ssl/private/mailserver.pem
TLSCACertificateFile                     /etc/apache2/ssl.crt/1_root_bundle.crt
TLSVerifyClient                         off
TLSRequired                             on
RequireValidShell                       no
TLSRenegotiate                          none
</IfModule>

I use the same certificate files for the https connection and that works all fine. When I do this:

openssl s_client -connect 127.0.0.1:21 -starttls ftp

I get a well working ssl connection. But when I do the same with my external ip address, I get this message:

CONNECTED(00000003) 140567084144296:error:140770FC:SSL routines:SSL23_GET_SERVER_HELLO:unknown protocol:s23_clnt.c:774:

no peer certificate available

No client certificate CA names sent

SSL handshake has read 91 bytes and written 300 bytes

New, (NONE), Cipher is (NONE) Secure Renegotiation IS NOT supported Compression: NONE Expansion: NONE

In the TLS log is no message when I do the external connection and in the proftpd.log is only this message:

Mar 02 13:22:38 domain.tld proftpd[31274] domain.tld (domain.tld[ip.addr.es.s]): FTP session opened.

Mar 02 13:22:38 domain.tld proftpd[31274] domain.tld (domain.tld[ip.addr.es.s]): FTP session closed.

I checked the firewall but that should not be the problem

Does someone know what I can do to get this working?

EDIT

My proftpd.conf

Include /etc/proftpd/modules.conf
UseIPv6                         on
IdentLookups off
ServerName                      "Debian"
ServerType                      standalone
DeferWelcome off
MultilineRFC2228                on
DefaultServer on
ShowSymlinks on
TimeoutNoTransfer               600
TimeoutStalled                  600
TimeoutIdle                     1200
DisplayLogin                    welcome.msg
DisplayChdir .message true
ListOptions "-l"
DenyFilter                      \*.*/
Port 0
<IfModule mod_dynmasq.c>
</IfModule>
MaxInstances                    30
User                            proftpd
Group                           nogroup
Umask 022 022
AllowOverwrite                  on
TransferLog /var/log/proftpd/xferlog
SystemLog   /var/log/proftpd/proftpd.log
<IfModule mod_quotatab.c>
QuotaEngine off
</IfModule>
<IfModule mod_ratio.c>
Ratios off
</IfModule>
<IfModule mod_delay.c>
DelayEngine on
</IfModule>
<IfModule mod_ctrls.c>
ControlsEngine        off
ControlsMaxClients    2
ControlsLog           /var/log/proftpd/controls.log
ControlsInterval      5
ControlsSocket        /var/run/proftpd/proftpd.sock
</IfModule>
<IfModule mod_ctrls_admin.c>
AdminControlsEngine off
</IfModule>
Include /etc/proftpd/tls.conf
Include /etc/proftpd/conf.d/
<Global>
DefaultRoot ~
RootLogin off
</Global>
DefaultRoot ~
ServerIdent on "FTP Server ready."
DefaultAddress domain.tld

My virtualhosts, they were automatically written in tls.conf by virtualmin

<VirtualHost ftp.domain1.tld>
Group domain1
User domain1
DefaultRoot ~
</VirtualHost>
<VirtualHost ftp.domain1.tld>
ServerName "domain1.tld"
<Anonymous /home/domain1/ftp>
User domain1
Group domain1
UserAlias anonymous ftp
<Limit WRITE>
DenyAll
</Limit>
ExtendedLog /home/domain1/logs/ftp.log
</Anonymous>
</VirtualHost>
<VirtualHost 1.2.3.4>
ServerName ftp.domain2.tld
<Anonymous /home/domain2/ftp>
User domain2
Group domain2
UserAlias anonymous ftp
<Limit WRITE>
DenyAll
</Limit>
RequireValidShell off
ExtendedLog /home/domain2/logs/ftp.log
<Directory />
AllowOverwrite on
</Directory>
</Anonymous>
</VirtualHost>

Ofcourse I replaced my domain and ip address with fake ones

Answer 1

It looks like your tls.conf configuration directives are applied only to the default "server config" vhost, and not to all vhosts in the server. Unlike Apache, ProFTPD configuration directives, outside of a <VirtualHost> section, are not applied globally. So you will need to explicitly make those mod_tls configurations global by using a <Global> section, i.e.:

<IfModule mod_tls.c>
  # Apply these configurations globally, to all vhosts
  <Global>
    TLSEngine on
    TLSLog /var/log/proftpd/tls.log
    TLSProtocol TLSv1
    TLSCipherSuite AES128+EECDH:AES128+EDH
    TLSOptions NoCertRequest AllowClientRenegotiations

    TLSRSACertificateFile /etc/ssl/certs/mailserver.pem
    TLSRSACertificateKeyFile /etc/ssl/private/mailserver.pem
    TLSCACertificateFile /etc/apache2/ssl.crt/1_root_bundle.crt
    TLSVerifyClient off
    TLSRequired on

    # Note: This particular directive is not specific to mod_tls;
    # I'm not sure why it's here, versus elsewhere.
    RequireValidShell no

    TLSRenegotiate none
  </Global>
</IfModule>

This behavior is covered in more detail in ProFTPD's Vhost howto.

Hope this helps!