General information about the "Abolish Root Daemons!" source release
--------------------------------------------------------------------

This package contains patches and code to let most network
software daemons run normally, but without root privileges.

Descriptions of files and directories in the dist tree:

  <toplevel>/
    Makefile       - build asp, set2gid, and testauth
    asp.c          - Authentication Server Process
    auth.h         - ioctl interface for /dev/auth and /dev/authsrvr
    checkpw.c      - programmatic interface to /dev/auth
    checkpw.h      - declarations of authentication routines
    readme.txt     - this file

  authmod/         - Linux kernel module,
                     implements /dev/auth and /dev/authsrvr
    Makefile       - build authmod.o
    authmod.c      - kernel module code
    authmod.h      - decls for authmod.c
    kutil.h        - generic kernel module utilities
    mykmalloc.c    - debugging kmalloc
    mykmalloc.h    - decls for mykmalloc.c

  chroot/          - code to test new chroot interface
    Makefile       - build breakchroot and mychroot
    breakchroot.c  - break out a chroot jail
    mychroot.c     - calls chroot() or rename_chroot()

  mysucap/         - obsolete Linux capability stuff

  pam_authc/       - PAM module to use /dev/auth
    Makefile       - build pam_authc.o
    pam_authc.c    - module code

  regression/      - regression tests
    ta.in1         - input for testauth
    ta.out1        - expected output for testauth

  patches/         - patches to daemon code and the kernel
    bsd-ftpd       - patch to BSD-ftpd for linux
    sshd           - patch to ssh-1.2.30
    cbpp           - kernel patch to implement cbpp group
    chroot         - kernel patch for chroot and rename_chroot
    setgroups      - kernel patch for new setgroups/setresgid

Instructions on using this software:

1. Get Linux kernel 2.2.17 working on your system; the sources
   should be in /usr/src/linux-2.2.17

2. Apply the three kernel patches:
                
     % cd patches
     % patch -p0 < cbpp*
     % patch -p0 < chroot*
     % patch -p0 < setgroups*

   Then recompile and reboot.

3. Create a 'cbpp' group.  Add a line to your /etc/rc.d/rc.local
   (or similar) like this:
   
     echo 102 > /proc/sys/kernel/cbpp-gid
     
   where 102 is the group id of cbpp.  Then execute this
   command directly to make it take effect now.

   (Optional) Test the new chroot and setgroups interfaces.  The
   mychroot program can be used to experiment with the former,
   and testauth experiments with the latter.

4. Get ssh-1.2.30 and apply the ssh patch.  Then

     % ./configure --enable-dev-auth
     % make

   Create a new user (say, 'sshd'), chown all the /etc/ssh* files
   to that user, and run sshd as that user.  Make this user's
   primary group be cbpp.

   The modified ssh daemon will work only if RSAAuthentication
   is disabled.  A short delay is introduced when sshd attempts
   to authenticate with an empty password.  The pseudoterminal
   remains owned by 'sshd' instead of the target users.  These
   issues will be fixed in a future version.

5. Get BSD-ftpd-0.3.2 and apply the ftpd patch.  Then

     % make

   Create a new user (say, 'initftp'), with primary group cbpp.
   Then arrange (in /etc/inetd.conf) to run ftpd as initftp.

   Create /etc/sandbox_users with the following contents

     # for ftp
     initftp -> ftp

   This means 'initftp' can become 'ftp' during anonymous
   FTP sessions.

   The modified ftp daemon should function normally in all
   respects.


We plan to patch more daemons in the near future to work with
our system.  If you have a daemon that you'd like ported, let
me know.  If you have questions, let me know.

-Scott McPeak
 smcpeak@cs.berkeley.edu