delorie.com/archives/browse.cgi   search  
Mail Archives: cygwin/2006/02/23/18:35:49

X-Spam-Check-By: sourceware.org
Message-ID: <43FE46C9.1050201@tundraware.com>
Date: Thu, 23 Feb 2006 17:35:37 -0600
From: Tim Daneliuk <tundra AT tundraware DOT com>
Reply-To: tundra AT tundraware DOT com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.12) Gecko/20050915
MIME-Version: 1.0
To: cygwin AT cygwin DOT com
Subject: Re: sshd, /etc/hosts.allow, & Alternate Access Methods
References: <43FDF37B DOT 8010006 AT tundraware DOT com> <Pine DOT GSO DOT 4 DOT 63 DOT 0602231249460 DOT 28431 AT access1 DOT cims DOT nyu DOT edu> <43FDFBE3 DOT 1040308 AT tundraware DOT com> <Pine DOT GSO DOT 4 DOT 63 DOT 0602231500000 DOT 862 AT access1 DOT cims DOT nyu DOT edu>
In-Reply-To: <Pine.GSO.4.63.0602231500000.862@access1.cims.nyu.edu>
X-TundraWare-MailScanner-Information: Please contact the ISP for more information
X-TundraWare-MailScanner: Found to be clean
X-IsSubscribed: yes
Mailing-List: contact cygwin-help AT cygwin DOT com; run by ezmlm
List-Subscribe: <mailto:cygwin-subscribe AT cygwin DOT com>
List-Archive: <http://sourceware.org/ml/cygwin/>
List-Post: <mailto:cygwin AT cygwin DOT com>
List-Help: <mailto:cygwin-help AT cygwin DOT com>, <http://sourceware.org/ml/#faqs>
Sender: cygwin-owner AT cygwin DOT com
Mail-Followup-To: cygwin AT cygwin DOT com
Delivered-To: mailing list cygwin AT cygwin DOT com

Igor Peshansky wrote:

> On Thu, 23 Feb 2006, Tim Daneliuk wrote:
> 
> 
>>Igor Peshansky wrote:
>>
>>
>>>On Thu, 23 Feb 2006, Tim Daneliuk wrote:
>>>
>>
>><SNIP>
>>
>>>Same reason -- Cygwin isn't really ACL-aware.  You can also restore
>>>the original ACLs by running something like "getfacl hosts.allow |
>>>setfacl -f - hosts.allow.orig" (assuming the owner stays the same).
>>>
>>>
>>>>-rwx------+ 1 tundra None  200 Feb 23 00:15 hosts.allow
>>>>-rwx------  1 tundra None  200 Feb 23 00:15 hosts.allow.orig
>>>>-rwx------+ 1 tundra None  407 Feb 23 00:15 hosts.deny
>>>
>>>These files should really be owned by SYSTEM (or whatever user sshd
>>>runs as).
>>
>>Ahh - that was the hint I needed.  But here is something very strange:
>>
>>As installed, hosts.allow is owned by the installing user - in this
>>case, "tundra" who is also an Administrator on the system.
> 
> 
> As installed by what?  I couldn't find anything that generates that file.
> 


I'm not sure.  I did a *complete* install of cygwin.  I dunno if it was
installed then, or when I ran ssh-host-config ...

>>sshd properly recognizes the rule found in this file.
> 
> 
> That's because it simply checks that a) permissions are no more than 700,
> and b) that the file is readable.  Both are satisfied, even though the
> owner is wrong.
> 
> 
>>HOWEVER, if I edit the file (to change allow rules), I *have* to chown
>>it to SYSTEM or ssh access outside localhost fails.
> 
> 
> Thank your editor which makes a copy.  Once you make a copy, Cygwin only
> copies the POSIX permissions (which are 700), so that the file is no
> longer readable by SYSTEM.  You can use the "getfacl | setfacl" trick to
> get the ACLs back.
> 

Ah, OK that explains it...

>>Stranger still is that once the file is owned by SYSTEM, it cannot be
>>further edited because I get a "Permission Denied" on it with emacs or
>>vi - strange considering that I am an Administrator on the system.
> 
> 
> Why is this strange?  Normally you are not supposed to see files that
> belong to other users (and SYSTEM *is* another user).  You can grab the
> ownership of the file and edit it, or make it world readable/writable and
> edit it.  Just don't forget to change it back to the way it was, or sshd
> will complain.
> 
> 
>>P.S. Did I mention that I hate the Windows security model ;)
> 
> 
> Most of the above is not really due to Windows -- it would happen on any
> system that has ACLs.
> 	Igor

Point taken.

(And thanks for your help ;)
-- 
----------------------------------------------------------------------------
Tim Daneliuk     tundra AT tundraware DOT com
PGP Key:         http://www.tundraware.com/PGP/


--
Unsubscribe info:      http://cygwin.com/ml/#unsubscribe-simple
Problem reports:       http://cygwin.com/problems.html
Documentation:         http://cygwin.com/docs.html
FAQ:                   http://cygwin.com/faq/

- Raw text -


  webmaster     delorie software   privacy  
  Copyright © 2019   by DJ Delorie     Updated Jul 2019