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

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

 Let's move this ahead.

 Given that the authentication cookie file's group-readability support
 already does not support specifying a group, I'm okay with leaving off
 support for specifying a particular group to 0.2.3.x.

 On the security issue:  We should check the permissions on the directory
 containing the socket.  We should warn if it's world-w or world-rx.  We
 should warn if it's group-w or group-rx and the option to make the socket
 group-accessible is not set or the group that owns the directory is not
 the same group as is getting rights on the socket.  (The
 check_private_dir() function in util.c can already do some of this.)

 I believe we can tell whether our host system implements file permissions
 properly on sockets by the trick of doing a chmod 000 then trying to
 connect to the socket. But that's potentially tricky to get right, and I'd
 rather just warn everywhere if people are leaving the socket in a visible
 directory.

-- 
Ticket URL: <https://trac.torproject.org/projects/tor/ticket/2972#comment:15>
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