Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 19 Dec 2015 11:12:09 +0800
From:      Ernie Luzar <luzar722@gmail.com>
To:        mike tancsa <mike@sentex.net>
Cc:        freebsd-questions <freebsd-questions@freebsd.org>
Subject:   Re: sftp, syslog level, chrooted users in a jail
Message-ID:  <5674CB09.3040000@gmail.com>
In-Reply-To: <151b73318f0.2765.e68d32c7521a042b3773fe36a0156dc7@sentex.net>
References:  <5671882E.3040509@sentex.net> <56748142.4030907@gmail.com> <151b73318f0.2765.e68d32c7521a042b3773fe36a0156dc7@sentex.net>

next in thread | previous in thread | raw e-mail | index | archive | help

>> Mike Tancsa wrote:
>>> I am trying to increase the verbosity of sftp's syslog, but am running
>>> into a problem because the users are chrooted and ssh is running in a 
>>> jail.
>>>
>>> My setup -- simple qjail with defaults
>>>
>>> I have inside, the user
>>>
>>> test1sftp:*:1002:1002:User &:/home/test1:/bin/false
>>>
>>> and in /etc/ssh/sshd_config I have
>>>
>>> Match user *
>>>    ChrootDirectory %h
>>>    ForceCommand internal-sftp -l debug1
>>>    AllowTcpForwarding no
>>>    PermitTunnel no
>>>    X11Forwarding no
>>>
>>> /home/test1sftp
>>>
>>> # ls -l /home/test1sftp
>>> total 27
>>> drwxr-xr-x    5 root       wheel      uarch   5 Dec 16 10:04 .
>>> drwxrwxr-x    2 root       wheel      uarch   4 Dec 16 10:37 dev
>>> drwxr-xr-x    3 test1sftp  test1sftp  uarch   6 Dec 16 10:37 uploadhere
>>>
>>>
>>> In the dev directory, if I make
>>> # ls -l /home/test1sftp/dev/
>>> total 2
>>> drwxrwxr-x  2 root  wheel  uarch 4 Dec 16 10:37 .
>>> drwxr-xr-x  5 root  wheel  uarch 5 Dec 16 10:04 ..
>>> srw-rw-rw-  2 root  wheel  uarch 0 Dec 16 10:05 log
>>> srw-------  2 root  wheel  uarch 0 Dec 16 10:05 logpriv
>>>
>>>
>>>
>>> ln /var/run/logpriv logpriv
>>> ln /var/run/log log
>>>
>>> I can get it to work.
>>>
>>>
>>> 10:44:58  sshd
>>> 10:44:58  sshd: Accepted publickey for test1sftp from xxxx port 30534
>>> ssh2: RSA 51:2e:....
>>> 10:44:58  sshd: User child is on pid 83522
>>> 10:44:58  sshd: Changed root directory to "/home/test1sftp"
>>> 10:44:58  sshd: Starting session: forced-command (config) 'internal-sftp
>>> -l verbose' for test1sftp from xxx  port 30534
>>> 10:44:58  internal-sftp
>>> 10:44:58  internal-sftp: received client version 3
>>> 10:44:58  internal-sftp: realpath "."
>>> 10:45:00  /usr/sbin/cron: (root) CMD (/usr/libexec/atrun)
>>> 10:45:02  internal-sftp: realpath "/uploadhere"
>>> 10:45:02  internal-sftp: stat name "/uploadhere"
>>> 10:45:04  internal-sftp: opendir "/uploadhere/"
>>> 10:45:04  internal-sftp: closedir "/uploadhere/"
>>> 10:45:04  internal-sftp: lstat name "/uploadhere/valid-ip.c"
>>> 10:45:04  internal-sftp: lstat name "/uploadhere/valid-ip.c"
>>> 10:45:04  internal-sftp: remove name "/uploadhere/valid-ip.c"
>>> 10:45:09  internal-sftp: open "/uploadhere/valid-ip.c" flags
>>> WRITE,CREATE,TRUNCATE mode 0644
>>> 10:45:09  internal-sftp: close "/uploadhere/valid-ip.c" bytes read 0
>>> written 615
>>> 10:45:10  internal-sftp: opendir "/uploadhere"
>>> 10:45:10  internal-sftp: closedir "/uploadhere"
>>> 10:45:11  internal-sftp
>>> 10:45:11  sshd: Received disconnect from xxxx: 11: disconnected by user
>>>
>>>
>>> I have a few hundred users. Apart from creating dev/log hard links for
>>> every home directory, is there a different way to go about this ?
>>>
>>> Are there any security issues I need to be aware of ?
>>>
>>>     ---Mike
>>>
>>
>> Let me be sure I understand your setup correctly, ssh, sftp, and all the
>> users are defined in the same jail.
>>
>> In the jail remove  ChrootDirectory %h option from sshd_config.
>>
mike tancsa wrote:
> Hi, thanks for the reply. Yes, all the users (a few hundred) are all in 
> one jail. However the users must be chrooted into their own directories 
> for security reasons. Hence, I cannot remove the chroot option and am 
> left with the issue of logging
> 

You state "all the users (a few hundred) are all in
one jail". Do you mean to say the users are in the SAME jail as ssh and 
sftp?

If that is the case then the ssh ChrootDirectory is inappropriate. It's 
intended for ssh running on the host and is the cause of your sftp log 
problems. Your host system is already protected by the ssh jail and the 
   file permissions of the users sftp directories. Over kill is hurting 
you in this case. It won't hurt to test it out before rejecting it.





Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?5674CB09.3040000>