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I'm having an issue with my FTP server. Every browser / client can connect to it except safari. A safari session freeze after the client emit the RETR comand and then issue a "425 Failed to establish connection" error.

I know connection to ftp from safari is possible (1and1 ftp server are accessible from safari) but I have no idea of what I'm missing or why this does not work.

Do you have any idea?

Thanks!

A Safari session :

Thu Nov 20 14:42:35 2014 [pid 8558] FTP command: Client "62.2.114.180", "USER proxy"
Thu Nov 20 14:42:35 2014 [pid 8558] [proxy] FTP response: Client "62.2.114.180", "331 Please specify the password."
Thu Nov 20 14:42:35 2014 [pid 8558] [proxy] FTP command: Client "62.2.114.180", "PASS <password>"
Thu Nov 20 14:42:35 2014 [pid 8557] [proxy] OK LOGIN: Client "62.2.114.180"
Thu Nov 20 14:42:35 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "230 Login successful."
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "SYST"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "215 UNIX Type: L8"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "PWD"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "257 "/""
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "TYPE I"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "200 Switching to Binary mode."
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "CWD /"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "250 Directory successfully changed."
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "PASV"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "227 Entering Passive Mode (172,30,0,248,228,76)."
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "SIZE r.html"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "213 173"
Thu Nov 20 14:42:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "RETR /r.html"
Thu Nov 20 14:43:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "425 Failed to establish connection."
Thu Nov 20 14:43:36 2014 [pid 8559] [proxy] FAIL DOWNLOAD: Client "62.2.114.180", "/r.html", 0.00Kbyte/sec
Thu Nov 20 14:43:36 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "CWD /"
Thu Nov 20 14:43:36 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "250 Directory successfully changed."
Thu Nov 20 14:43:37 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "PASV"
Thu Nov 20 14:43:37 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "227 Entering Passive Mode (172,30,0,248,228,101)."
Thu Nov 20 14:43:37 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "SIZE r.html"
Thu Nov 20 14:43:37 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "213 173"
Thu Nov 20 14:43:37 2014 [pid 8559] [proxy] FTP command: Client "62.2.114.180", "RETR /r.html"
Thu Nov 20 14:44:37 2014 [pid 8559] [proxy] FTP response: Client "62.2.114.180", "425 Failed to establish connection."
Thu Nov 20 14:44:37 2014 [pid 8559] [proxy] FAIL DOWNLOAD: Client "62.2.114.180", "/r.html", 0.00Kbyte/sec

As I said before it work as expected on other browser (mobile and desktop) and FTP clients. For example Chrome:

Thu Nov 20 14:38:05 2014 [pid 8523] FTP command: Client "62.2.114.180", "USER proxy"
Thu Nov 20 14:38:05 2014 [pid 8523] [proxy] FTP response: Client "62.2.114.180", "331 Please specify the password."
Thu Nov 20 14:38:05 2014 [pid 8523] [proxy] FTP command: Client "62.2.114.180", "PASS <password>"
Thu Nov 20 14:38:05 2014 [pid 8522] [proxy] OK LOGIN: Client "62.2.114.180"
Thu Nov 20 14:38:05 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "230 Login successful."
Thu Nov 20 14:38:05 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "SYST"
Thu Nov 20 14:38:05 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "215 UNIX Type: L8"
Thu Nov 20 14:38:05 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "PWD"
Thu Nov 20 14:38:05 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "257 "/""
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "TYPE I"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "200 Switching to Binary mode."
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "PASV"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "227 Entering Passive Mode (172,30,0,248,227,196)."
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "SIZE /s.html"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "213 180"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "CWD /s.html"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "550 Failed to change directory."
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "PASV"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "227 Entering Passive Mode (172,30,0,248,228,14)."
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "RETR /s.html"
Thu Nov 20 14:38:06 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "150 Opening BINARY mode data connection for /s.html (180 bytes)."
Thu Nov 20 14:38:07 2014 [pid 8526] [proxy] OK DOWNLOAD: Client "62.2.114.180", "/s.html", 180 bytes, 1.39Kbyte/sec
Thu Nov 20 14:38:07 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "226 Transfer complete."
Thu Nov 20 14:38:07 2014 [pid 8526] [proxy] FTP command: Client "62.2.114.180", "QUIT"
Thu Nov 20 14:38:07 2014 [pid 8526] [proxy] FTP response: Client "62.2.114.180", "221 Goodbye."

I'm using vsftpd and my conf is :

# Example config file /etc/vsftpd.conf
#
# The default compiled in settings are fairly paranoid. This sample file
# loosens things up a bit, to make the ftp daemon more usable.
# Please see vsftpd.conf.5 for all compiled in defaults.
#
# READ THIS: This example file is NOT an exhaustive list of vsftpd options.
# Please read the vsftpd.conf.5 manual page to get a full idea of vsftpd's
# capabilities.
#
#
# Run standalone?  vsftpd can run either from an inetd or as a standalone
# daemon started from an initscript.
listen=YES
#
# Run standalone with IPv6?
# Like the listen parameter, except vsftpd will listen on an IPv6 socket
# instead of an IPv4 one. This parameter and the listen parameter are mutually
# exclusive.
#listen_ipv6=YES
#
# Allow anonymous FTP? (Disabled by default)
anonymous_enable=NO
#
# Uncomment this to allow local users to log in.
# local_enable=YES
#
# Uncomment this to enable any form of FTP write command.
# write_enable=YES
#
# Default umask for local users is 077. You may wish to change this to 022,
# if your users expect that (022 is used by most other ftpd's)
local_umask=022
#
# Uncomment this to allow the anonymous FTP user to upload files. This only
# has an effect if the above global write enable is activated. Also, you will
# obviously need to create a directory writable by the FTP user.
#anon_upload_enable=YES
#
# Uncomment this if you want the anonymous FTP user to be able to create
# new directories.
#anon_mkdir_write_enable=YES
#
# Activate directory messages - messages given to remote users when they
# go into a certain directory.
dirmessage_enable=NO
#
# If enabled, vsftpd will display directory listings with the time
# in  your  local  time  zone.  The default is to display GMT. The
# times returned by the MDTM FTP command are also affected by this
# option.
use_localtime=YES
#
# Activate logging of uploads/downloads.
xferlog_enable=YES
#
# Make sure PORT transfer connections originate from port 20 (ftp-data).
connect_from_port_20=YES
#
# If you want, you can arrange for uploaded anonymous files to be owned by
# a different user. Note! Using "root" for uploaded files is not
# recommended!
#chown_uploads=YES
#chown_username=whoever
#
# You may override where the log file goes if you like. The default is shown
# below.
#xferlog_file=/var/log/vsftpd.log
#
# If you want, you can have your log file in standard ftpd xferlog format.
# Note that the default log file location is /var/log/xferlog in this case.
#xferlog_std_format=YES
#
# You may change the default value for timing out an idle session.
#idle_session_timeout=600
#
# You may change the default value for timing out a data connection.
#data_connection_timeout=120
#
# It is recommended that you define on your system a unique user which the
# ftp server can use as a totally isolated and unprivileged user.
#nopriv_user=ftpsecure
#
# Enable this and the server will recognise asynchronous ABOR requests. Not
# recommended for security (the code is non-trivial). Not enabling it,
# however, may confuse older FTP clients.
#async_abor_enable=YES
#
# By default the server will pretend to allow ASCII mode but in fact ignore
# the request. Turn on the below options to have the server actually do ASCII
# mangling on files when in ASCII mode.
# Beware that on some FTP servers, ASCII support allows a denial of service
# attack (DoS) via the command "SIZE /big/file" in ASCII mode. vsftpd
# predicted this attack and has always been safe, reporting the size of the
# raw file.
# ASCII mangling is a horrible feature of the protocol.
#ascii_upload_enable=YES
#ascii_download_enable=YES
#
# You may fully customise the login banner string:
# ftpd_banner=Welcome!
#
# You may specify a file of disallowed anonymous e-mail addresses. Apparently
# useful for combatting certain DoS attacks.
#deny_email_enable=YES
# (default follows)
#banned_email_file=/etc/vsftpd.banned_emails
#
# You may restrict local users to their home directories.  See the FAQ for
# the possible risks in this before using chroot_local_user or
# chroot_list_enable below.
#chroot_local_user=YES
#
# You may specify an explicit list of local users to chroot() to their home
# directory. If chroot_local_user is YES, then this list becomes a list of
# users to NOT chroot().
# (Warning! chroot'ing can be very dangerous. If using chroot, make sure that
# the user does not have write access to the top level directory within the
# chroot)
chroot_local_user=YES
#chroot_list_enable=YES
# (default follows)
#chroot_list_file=/etc/vsftpd.chroot_list
#
# You may activate the "-R" option to the builtin ls. This is disabled by
# default to avoid remote users being able to cause excessive I/O on large
# sites. However, some broken FTP clients such as "ncftp" and "mirror" assume
# the presence of the "-R" option, so there is a strong case for enabling it.
#ls_recurse_enable=YES
#
# Customization
#
# Some of vsftpd's settings don't fit the filesystem layout by
# default.
#
# This option should be the name of a directory which is empty.  Also, the
# directory should not be writable by the ftp user. This directory is used
# as a secure chroot() jail at times vsftpd does not require filesystem
# access.

secure_chroot_dir=/var/run/vsftpd/empty
#
# This string is the name of the PAM service vsftpd will use.
pam_service_name=vsftpd.virtual
#

# This option specifies the location of the RSA certificate to use for SSL
# encrypted connections.
rsa_cert_file=/etc/ssl/certs/ssl-cert-snakeoil.pem

# This option specifies the location of the RSA key to use for SSL
# encrypted connections.
rsa_private_key_file=/etc/ssl/private/ssl-cert-snakeoil.key

force_local_data_ssl=NO
force_local_logins_ssl=NO

ssl_enable=NO

check_shell=NO
chmod_enable=NO
dirlist_enable=YES
guest_enable=YES

no_anon_password=NO
pasv_enable=YES
pasv_promiscuous=NO

pasv_max_port=58500
pasv_min_port=58300

local_enable=YES
virtual_use_local_privs=YES
write_enable=NO
user_sub_token=$USER
chroot_local_user=YES
hide_ids=YES
guest_username=ftp
log_ftp_protocol=YES
Pierre
  • 123
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1 Answers1

2

... "62.2.114.180", "227 Entering Passive Mode (172,30,0,248,228,14).

It looks like that your server has a private IP but your client a public IP. From that I assume that your server is inside some local network behind a router which will forward most of the ports to the server so that FTP data connections work (at least 58300..58500, which are pasv_min_port and pasv_max_port in your configuration.

But, the server still knows only its internal IP address of 172.30.0.248 and expects the FTP client to connect to this address (in this case 172.30.0.248 port 58382). If the FTP client only implements strict RFC959 it will try to connect to this address and will of course fail to connect because it is not reachable from his site. Other FTP clients might instead ignore the IP given inside the response to PASV and instead connect to the IP address of the server. While this is against the standard it works around situations like yours and can also be more secure.

In summary: you expect the FTP client to work around a configuration problem on your site. Some do, others don't. For correct configuration of vsftp behind a router see for example http://flukylogs.blogspot.de/2012/01/vsftpd-behind-routerfirewall.html (first hit with google).

Steffen Ullrich
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