Path: utzoo!utgpu!news-server.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!auspex!guy
From: guy@auspex.auspex.com (Guy Harris)
Newsgroups: comp.unix.questions
Subject: Re: Anonymous FTP problem
Keywords: crt0: no /dev/zero
Message-ID: <4217@auspex.auspex.com>
Date: 31 Oct 90 01:42:16 GMT
References: <1990Oct22.182238.7120@cca.PUE.UDLAP.MX> <1990Oct24.074454.9992@uwasa.fi>
Distribution: comp
Organization: Auspex Systems, Santa Clara
Lines: 45

>the other alternative is to duplicate the
>necessary files (i think you'll need at least the shared
>libraries in addition to /dev/zero).

You need all the files that the FTPD(8C) man page says you need:

     In the last case, ftpd takes special  measures  to  restrict
     the  client's  access  privileges.   The  server  performs a
     chroot(2) command to the home directory of the ftp user.  In
     order  that  system  security  is not breached, it is recom-
     mended that the ftp subtree be constructed with  care;   the
     following rules are recommended.

     ftp     Make the home directory owned by ftp and  unwritable
             by anyone.

     ~ftp/bin
             Make this directory  owned  by  the  super-user  and
             unwritable  by  anyone.   The program ls(1V) must be
             present to support the list commands.  This  program
             should  have  mode  111.   Since the default /bin/ls
             command is linked with a shared library, so you need
             to set up the files for dynamic linking as well.

     ~ftp/usr/lib/ld.so
             the runtime loader must be present and executable.

     ~ftp/dev/zero
             used by the runtime loader,  create  this  with  the
             command mknod zero c 3 12.

     ~ftp/usr/lib/libc.so.*
             should be a copy of the latest version of the shared
             C library.

     ~ftp/etc
             Make this directory  owned  by  the  super-user  and
             unwritable  by  anyone.   The  files  passwd(5)  and
             group(5) must be present for the ls command to  work
             properly.  These files should be mode 444.

     ~ftp/pub
             Make this directory  mode  777  and  owned  by  ftp.
             Users should then place files which are to be acces-
             sible via the anonymous account in this directory.