Bonjour à tous,
J’ai installé un serveur Proftpd (connexion en SFTP) sur un Debian et j’ai quelques soucis. Tout d’abord, j’ai besoin d’enfermer les utilisateurs dans leur home afin qu’ils ne puissent pas remonter à la racine et accéder à des répertoires sensibles. En faisant des recherches, j’ai bien compris que c’était l’objectif du DefaultRoot ~ mais chez moi ça ne marche pas vraiment. En fait, l’utilisateur est bien dans son home dès la connexion, mais il peut très bien remonter a grands coups de “cd …” ou même en tapant “cd /”. J’aimerais savoir si vous avez une idée de pourquoi chez moi ça ne marche pas alors que ça a l’air de fonctionner chez les autres. Voici mon fichier de config :
[code]#
/etc/proftpd/proftpd.conf – This is a basic ProFTPD configuration file.
To really apply changes reload proftpd after modifications.
Includes DSO modules
Include /etc/proftpd/modules.conf
Set off to disable IPv6 support which is annoying on IPv4 only boxes.
UseIPv6 on
If set on you can experience a longer connection delay in many cases.
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 *.*/
Use this to jail all users in their homes
DefaultRoot ~
Users require a valid shell listed in /etc/shells to login.
Use this directive to release that constrain.
RequireValidShell off
Port 21 is the standard FTP port.
Port 21
In some cases you have to specify passive ports range to by-pass
firewall limitations. Ephemeral ports can be used for that, but
feel free to use a more narrow range.
PassivePorts 49152 65534
If your host was NATted, this option is useful in order to
allow passive tranfers to work. You have to use your public
address and opening the passive ports used on your firewall as well.
MasqueradeAddress 1.2.3.4
This is useful for masquerading address with dynamic IPs:
refresh any configured MasqueradeAddress directives every 8 hours
# DynMasqRefresh 28800To prevent DoS attacks, set the maximum number of child processes
to 30. If you need to allow more than 30 concurrent connections
at once, simply increase this value. Note that this ONLY works
in standalone mode, in inetd mode you should use an inetd server
that allows you to limit maximum number of processes per service
(such as xinetd)
MaxInstances 30
Set the user and group that the server normally runs at.
User proftpd
Group nogroup
Umask 022 is a good standard umask to prevent new files and dirs
(second parm) from being group and world writable.
Umask 022 022
Normally, we want files to be overwriteable.
AllowOverwrite on
Uncomment this if you are using NIS or LDAP via NSS to retrieve passwords:
PersistentPasswd off
This is required to use both PAM-based authentication and local passwords
AuthOrder mod_auth_unix.c
Be warned: use of this directive impacts CPU average load!
Uncomment this if you like to see progress and transfer rate with ftpwho
in downloads. That is not needed for uploads rates.
UseSendFile off
TransferLog /var/log/proftpd/xferlog
SystemLog /var/log/proftpd/proftpd.log
Delay engine reduces impact of the so-called Timing Attack described in
http://security.lss.hr/index.php?page=details&ID=LSS-2004-10-02
It is on by default.
DelayEngine on ControlsEngine off ControlsMaxClients 2 ControlsLog /var/log/proftpd/controls.log ControlsInterval 5 ControlsSocket /var/run/proftpd/proftpd.sock AdminControlsEngine offAlternative authentication frameworks
#Include /etc/proftpd/ldap.conf
#Include /etc/proftpd/sql.conf
This is used for FTPS connections
Include /etc/proftpd/tls.conf
A basic anonymous configuration, no upload directories.
<Anonymous ~ftp>
User ftp
Group nogroup
# We want clients to be able to login with “anonymous” as well as “ftp”
UserAlias anonymous ftp
# Cosmetic changes, all files belongs to ftp user
DirFakeUser on ftp
DirFakeGroup on ftp
RequireValidShell off
# Limit the maximum number of anonymous logins
MaxClients 10
# We want ‘welcome.msg’ displayed at login, and ‘.message’ displayed
# in each newly chdired directory.
DisplayLogin welcome.msg
DisplayChdir .message
# Limit WRITE everywhere in the anonymous chroot
<Directory *>
DenyAll
# Uncomment this if you’re brave.
#
# # Umask 022 is a good standard umask to prevent new files and dirs
# # (second parm) from being group and world writable.
# Umask 022 022
#
# DenyAll
#
#
# AllowAll
#
#
[/code]
Par ailleurs, si vous voyez des choses à améliorer, je prends tous les conseils. Mais pour l’heure, j’aimerais bien que les utilisateurs soient complètement enfermés dans leur home.
Merci d’avance.
Naoki