Re: Chroot: sshd bug ? user redirects to root folder.

There is no possibility to implement this mechanism ?

----- Original Message ----- 
From: "Dennis Nasarov" <[email protected]>
To: "Riccardo Castellani" <[email protected]>
Cc: <[email protected]>
Sent: Sunday, February 27, 2011 6:45 PM
Subject: Re: Chroot: sshd bug ? user redirects to root folder.



On Feb 27, 2011, at 5:21 PM, Riccardo Castellani wrote:

> I installed openssh-5.6p1 into my Fedora server and I run this service 
> into chroot mode.
> I think to have found out a BUG into this package, specifically into sshd 
> service:
>
> if remote user tries to connect to this service, where its home directory 
> is unaccessible because it doesn't respect right permissions (execution 
> permission of owner is missed or home directory is missing), he comes 
> automatically into root folder of chroot.

It's not a bug, it's a feature ;) (c)

> I think sshd should have to deny this login or at least sshd_config should 
> have to contain the option to set this specifc behaviour; for example into 
> Fedora distributions, there is "DEFAULT_HOME" option in /etc/login.defs 
> file to permit this behavior.

No.

> Yes it's true, I can restrict access to specific users or use PAM module, 
> but for security reasons I need to make sure myself to restrict access 
> ONLY to home folder of user.
> I also could use PAM modules, but it's only available pam_mkhomedir.so 
> which creates home folder if this one is not existing; I need 
> pam_homecheck.so but it's available only as package for OpenSuse.
> Suggestions ?