[tor-bugs] #2972 [Tor Client]: Allow ControlSocket to be group writable

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#2972: Allow ControlSocket to be group writable
-------------------------+--------------------------------------------------
 Reporter:  lunar        |          Owner:                    
     Type:  enhancement  |         Status:  needs_review      
 Priority:  normal       |      Milestone:  Tor: 0.2.2.x-final
Component:  Tor Client   |        Version:  Tor: unspecified  
 Keywords:               |         Parent:                    
   Points:               |   Actualpoints:                    
-------------------------+--------------------------------------------------

Comment(by nickm):

 I like this idea, but think that depending on the default group seems
 error-prone.  Perhaps instead of a boolean, it could take the name of a
 group, and chgrp the socket before doing the chmod?  That seems less
 likely to wind up with surprising results.

 Also, could we use fchmod here?  I don't _think_ we have a race-condition
 to worry about here, but it's best to err on the side of safety.

 Finally, the linux unix(7) manpage says:
 {{{
 Connecting  to  the
        socket  object  requires  read/write permission.  This behavior
 differs
        from many BSD-derived systems which ignore permissions for  Unix
 sock‐
        ets.  Portable programs should not rely on this feature for
 security.
 }}}

 Is this true nowadays?  If so, we shouldn't give people a false sense of
 security by allowing this option where it won't work.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2972#comment:7>
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