****Re: simple question with home serviing ruby on rails web site

[Paul Howarth]

Craig White wrote:
> On Sat, 2008-06-14 at 16:51 +0100, Paul Howarth wrote:
>> On Sat, 14 Jun 2008 08:05:56 -0700
>> Craig White <craigwhite at azapple.com> wrote:
>>
>>> I'm running in permissive mode so all I'm getting is warnings but I'm
>>> wondering the best way to solve this...
>>>
>>> error every time httpd starts...
>>>
>>> SELinux has denied httpd access to potentially mislabeled file(s)
>>> (./svn-new). This means that SELinux will not allow httpd to use these
>>> files. It is common for users to edit files in their home directory or
>>> tmp directories and then move (mv) them to system directories. The
>>> problem is that the files end up with the wrong file context which
>>> confined applications are not allowed to access. Allowing AccessIf you
>>> want httpd to access this files, you need to relabel them using
>>> restorecon -v './svn-new'. You might want to relabel the entire
>>> directory using restorecon -R -v './svn-new'. Additional
>>> InformationSource Context:
>>> system_u:system_r:httpd_t:SystemLow-SystemHighTarget Context:
>>> user_u:object_r:user_home_tTarget Objects:  ./svn-new [ dir ]Source:
>>> httpdSource Path:  /usr/sbin/httpd
>>>
>>>
>>> /home/craig/svn-new is an svn checkout and is the 'RAILS ROOT'
>>> directory for the web server.
>>>
>>> $ ls -ldZ /home/craig/svn-new/
>>> drwxrwxr-x  craig craig
>>> user_u:object_r:user_home_t      /home/craig/svn-new/
>>>
>>> This is on Fedora 9. In the past, I could have used
>>> system-config-security and set selinux to allow web page serving from
>>> user home directories but I don't see that tool any more.
>>>
>>> What's the best way to handle this?
>> Easiest is just to fix the contexts of the files:
>>
>> # semanage fcontext -a -t httpd_sys_content_t
>> '/home/craig/svn-new(/.*)?'
>> # restorecon -rv /home/craig/svn-new
>>
>> I'm not familiar with rails or how you maintain your svn checkout, so
>> httpd_sys_content_t may not be the appropriate type for all of the
>> content (are there any scripts in there, are you uploading content via
>> ftp, samba, etc.?). Since you're in permissive mode, it's not going to
>> cause you any problem other than possibly different warnings though.
>> If you maintain the checkout by manually doing an "svn update" from
>> your regular account, and the content isn't "executed" by httpd,
>> httpd_sys_content_t should be fine.
> ----
> Thanks Paul...miss you on the Fedora-list

Thanks; when I had the first of my two children in September 2005 there 
were a lot more demands on my time and some things I'd enjoyed devoting 
a lot of my time to just had to go, and fedora-list was one of those.

> I'm a bit confused myself because in essence, httpd is just a proxy to
> the ruby/rails 'mongrel' which is a http server in ruby running the ruby
> processes and is providing dhtml on higher ports as the user.
> 
> FWIW...httpd runs as user 'apache' (as ususal)
>     mongrels run as regular 'user' (me)
>     all files and folders inside the subdirectory we are discussing...
>     (/home/craig/svn-new) are owned by me (not root, not apache)

The conventional unix ownership and permissions make very little 
difference as far as SELinux is concerned, so although you need to get 
them right, they're not going to affect the file contexts needed.

What context is mongrels running in (try the -Z option of ps)? How does 
that process get started (via an initscript?)?

> I ran the commands that you suggested (ignoring the alerts raised by the
> first command) and then restarted httpd service and got a new alert...
> 
> SELinux is preventing the httpd from using potentially mislabeled files
> (2F7661722F746D702F6B646563616368652D63726169672F6B70632F6B64652D69636F6E2D63616368652E64617461202864656C6574656429). Detailed Description[SELinux is in permissive mode, the operation would have been denied but was permitted due to permissive mode.]SELinux has denied httpd access to potentially mislabeled file(s) (2F7661722F746D702F6B646563616368652D63726169672F6B70632F6B64652D69636F6E2D63616368652E64617461202864656C6574656429).
> 
> This means that SELinux will not allow httpd to use these files. It is
> common for users to edit files in their home directory or tmp
> directories and then move (mv) them to system directories. The problem
> is that the files end up with the wrong file context which confined
> applications are not allowed to access. Allowing AccessIf you want httpd
> to access this files, you need to relabel them using restorecon -v
> '2F7661722F746D702F6B646563616368652D63726169672F6B70632F6B64652D69636F6E2D63616368652E64617461202864656C6574656429'.
> 
> You might want to relabel the entire directory using restorecon -R -v
> ''. Additional InformationSource Context:
> unconfined_u:system_r:httpd_tTarget Context:
> unconfined_u:object_r:user_tmp_tTarget Objects:
> 2F7661722F746D702F6B646563616368652D63726169672F6B70632F6B64652D69636F6E2D63616368652E64617461202864656C6574656429
> 
> This is my new development system and I obviously will be doing svn
> commit/update operations in this directory and it was created by a
> checkout. 
> 
> There is a 'tmp' directory in the RAILS_ROOT directory
> (/home/craig/svn-new/th-db/branches/phase5) which holds...
> - temporary pdf files put there by ruby before 'merging' database data
> with pdftk
> - subdirectories but the only 'non-empty' subdirectory is one called
> 'pids' which holds the pid for the backgroundrd (a separate ruby process
> that runs long running processes in the background).
> 
> I'm wondering if this directory shouldn't have some different
> contexts...
> 
> My desire is to have a plan to manage selinux contexts when it comes
> time to merge this on my production server.

You probably need to run the ruby process confined so that it generates 
files that are readable by httpd. It might actually work ok running as 
httpd_t given how closely related the processes are.

Paul.