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Re: ssh restrictions (/etc/ssh_config)

Subject: Re: ssh restrictions (/etc/ssh_config)
Date: Wed, 03 Oct 2007 14:46:09 +0100

On Fri, 2007-09-21 at 08:43 +0200, Rainer Peter Feller wrote:
On Thu, 2007-09-20 at 08:30 -0400, Greg Wooledge wrote:
On Wed, Sep 19, 2007 at 09:39:56AM +0200, Rainer Peter Feller wrote:
On Tue, 2007-09-18 at 12:19 +0100, Martin Simovic wrote:
is there a way to restrict commands passed to ssh (client) to override
command line options
So I made a patch by myself, which I also update with every new release
For the Patch to openssh-4.7p1 see attachment
The name of the not overidable configfile is ssh_config_p

What prevents people from bypassing this by using an unpatched client?
a careful setup
the user can write only on filesystems where files are not executable
AND all binaries have to be static, so you need
no /lib/ld-linux-2.so :-) 


Hi,

thanks for a patch, works perfectly as expected.
however, i still have a next problem:

my setup is : chrooted environment (using libpam-chroot) where is
supposed to reside only shell (statically compiled bash) and ssh
client. 

i have recompiled ssh client (witch patch applied) statically
using ./configure --with-ldflags=-static at configure time.

the problem is that to make an ssh client work, (even compiled static
witch all the libraries found using ldd /usr/bin/ssh) it still needs to
load dynamic libs in order to get an UID and all the stuff needed for
DNS resolving.

so i end up witch: static bash, static ssh and

etc/ld.so.cache
lib/ld-linux.so.2
lib/tls/i686/cmov/libc.so.6
lib/tls/i686/cmov/libnsl.so.1
lib/tls/i686/cmov/libnss_compat.so.2
lib/tls/i686/cmov/libnss_dns.so.2
lib/tls/i686/cmov/libresolv.so.2

all just to make ssh client work.

would there be a way how to get rid of all libraries?
in my opinion a static compiled client makes no sense if there is still
a need to load shared libraries?

thanks a lot,

martin.

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