Using /bin/sh to exec subsystems [PATCH]

[Jason Stone]

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> Using sftp-server as a login shell works fine for sftp, but it's
> causing some problems with other services. There really needs to be a
> cleaner way to restrict access to specific subsystems.

A similar problem that I've run into is when I want to allow limited
access with keys (eg, I want a user to be able to only run one command, or
to only be able to port forward, etc).  In order for the command-squashed
command to be run, the user has to have a valid shell.  Unfortunately, a
valid shell usually implies to the rest of the system that the user is
allowed to have shell access.  So now I have to worry about the other
services on the machine doing the right thing and denying access, even
though the user has a valid shell.

So in both cases (subsystems, command-squashed commands), why not have
sshd fork and exec the command directly?  Why go through the shell at all?


 -Jason

 ---------------------------
 If the Revolution comes to grief, it will be because you and those you
 lead have become alarmed at your own brutality.         --John Gardner



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