Authentization by using public key

[Rob Landley]

On 06/29/2011 04:02 AM, Pavel Muller wrote:
> Hello,
> 
> I am administrator of SuperMicro server with IPMI card with Dropbear ssh
> server v0.50. I would ask you for help with problem with login on ssh
> server by using public key.

Ok.

> My question is:
> 
> Is there possibility how to change ~/ directory in Dropbear ssh server?

At the Linux level, you can set ~ to anything you like in /etc/passwd.
You can also --bind mount an existing directory or an existing file
(even out of a read-only filesystem).

  touch /tmp/walrus
  mount --bind /tmp/walrus ~/.ssh/authorized_keys

The --bind target has to exist: if you haven't got a ~/.ssh directory in
your read-only filesystem... how did you put dropbear in it?

If you have to patch an existing pathological binary-only system, you
can always do something horrible like:

  mount --bind /tmp/walrus /etc/passwd &&
  dropbear &
  sleep 5 &&
  umount /etc/passwd

With current kernels, running said script under "unshare -n" might be
more polite to the rest of the system...

> For example, new path would be: /conf/home/admin/.ssh/authorized_keys.
> If it is possible, where in Dropbear configuration could I do it?
> 

My first guess would be svr-authpubkey.c line 218, but that's just 30
seconds with grep talking...

Rob