mirroring a loop device across an ssh connection

[Jim Knoble]

Circa 2006-12-01 12:35 dixit Jason:

: all,
: 
: I've been looking into a secure way of accessing a remote loopback 
: encrypted partition securely via openssh.
: 
: The basic idea I have currently is that a file/partition is connected to 
: /dev/loop0 on a remote server, which I have an ssh connection to.  I 
: hold the key (for cryptsetup via dm_crypt) on the local client.  I'd 
: like to mirror the loop device of the server on the client.  Once that 
: is done, I would run cryptsetup with the key on the client and mount as 
: normal.

This sounds like you'll need unix domain sockets.  The following may be
of help:

    http://bugzilla.mindrot.org/show_bug.cgi?id=1256

: The end application would be for remote secure backup (rsync?) of a 
: second encrypted volume on the client.  It is assumed that the remote 
: server is untrusted, hence, not running cryptsetup/dm_crypt on the server.
: 
: So far, I've looked at Rex/sfs [1], pseudo-tty programming, and a little 
: of unix domain sockets.  I'm more familiar with network socket 
: programming, though.  My main holdup right now is my lack of familiarity 
: with openssh internals.  If someone could point to the right section of 
: the src tree, perhaps with a nudge towards how to do this securely, it 
: would greatly appreciated.

-- 
jim knoble  |  jmknoble at pobox.com  |  http://www.pobox.com/~jmknoble/
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