tar czf /home/sysconfig.tar.gz /etc /var/named /var/lib/wicd

tar xf /home/sysconfig.tar.gz -C /root

#!/bin/sh
# run as root, of course
# completely untested and done from memory - this might not have a chance of
# working without some edits, but the proposed idea should be clear
cd $HOME
for dir in /home/* ; do 
  if [ -d $dir ]; then
    # Add exclusions here
    case $dir in
      ftp)
        break ;;
    esac
    _USER=$(echo $dir | cut -d/ -f3)
    grep ^${_USER}\: etc/passwd >> /etc/passwd
    grep ^${_USER}\: etc/shadow >> /etc/shadow
  fi
done
# Note that this does not copy custom groups over; that's left
# as an exercise for the reader
# Also note that I would break this up into functions if I were
# actually going to use it: getting the list of directories would
# be a separate function, the exclusions-check would be a function,
# and so on, in such a way that the end result would just be this:
#!/bin/sh
# (function declarations here)
# get_dirs
# exclude_dirs
# write_file

#!/bin/sh

# Copyright 2009 Robby Workman <rworkman@slackware.com>, Northport, AL, USA
# All rights reserved.
#
# Redistribution and use of this script, with or without modification, is
# permitted provided that the following conditions are met:
#
# 1. Redistributions of this script must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR IMPLIED
# WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
# EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
# OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
# ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

# This is written mostly as an academic exercise for *me* - if it actually
# proves to be useful, that's great; if not, oh well.  Suggestions for 
# improvement are welcome, but I make no promises about continuing to 
# maintain this script, even if the suggestions are wonderful.
# Because this is an academic exercise, and because I hope it can be a
# learning tool for others, I'm going to include lots of comments that 
# I might otherwise omit.

# Some directories in $HOMEDIR might need to be excluded:  if a directory
# does not match an existing user (e.g. SBo repo at /home/SBo) or the
# existing user is already present in the passwd file (e.g. ftp user)
# You don't need to edit the line below - simply pass as many values as
# you wish (space separated) to DIR_EXCLUDES when invoking this script
# As an example:  DIR_EXCLUDES="SBo slackware" ./TODO.sh
DIR_EXCLUDES+=ftp

# Set some important locations
HOMEDIR=${HOMEDIR:-/home}       # some systems may use /users
BACKUPDIR=${BACKUPDIR:-/root}   # toplevel location of the backup etc/ tree

# This script expects /root/etc/{passwd,shadow} by default, but that's easy
# enough to change by passing the PASSWD_BAK and/or SHADOW_BAK values 
PASSWD_BAK=${PASSWD_BAK:-"${BACKUPDIR}/etc/passwd"}
SHADOW_BAK=${SHADOW_BAK:-"${BACKUPDIR}/etc/shadow"}

# If everything finishes successfully, then these will catch the output
PASSWD_ADD=${PASSWD_ADD:-/etc/passwd.additions}
SHADOW_ADD=${SHADOW_ADD:-/etc/shadow.additions}

# Ideally, nothing below this line needs to be edited
###############################################################################

set -eu

# Declare some temporary files
TEMP_USERS=$(mktemp)    # temporary user list
T_PASSWD=$(mktemp)      # passwd file additions
T_SHADOW=$(mktemp)      # shadow file additions

# If the script exits, trap that and clean up our temporary files
trap "do_cleanup ; exit 0" EXIT;
trap "do_cleanup ; exit 1" SIGINT SIGTERM;

# Here's our cleanup function
do_cleanup() {
  rm -f ${T_PASSWD} ${T_SHADOW} ${TEMP_USERS}
}

# If no user account matches a directory entry, say something...
error_nouser() {
  printf "\n\tWARNING: No \"$1\" user account is present in the
        ${SHADOW_BAK} file -- ignoring ${HOMEDIR}/$1 \n\n"
}
# Make sure the temporary files are securely used
make_vars_secure() {
  chown root:root ${TEMP_USERS} ${T_PASSWD} ${T_SHADOW}
  chmod 0644 ${TEMP_USERS} ${T_PASSWD} ${T_SHADOW}
}

# This function will grab the list of user accounts
get_users() {
  for dir in ${HOMEDIR}/* ; do
    printf "$(basename ${dir})\n" >> ${TEMP_USERS} ;
  done
}

# This function will prune the excluded dirs from the user list
prune_users() {
  for exclude in ${DIR_EXCLUDES} ; do
    sed -i "/^${exclude}$/d" ${TEMP_USERS} ;
  done
}

# This function will grab the passwd info for each user and concatenate it
# (sorted by uid) into a temporary file
get_passwd_info() {
  local UNSORTED_PASSWD=$(mktemp)
  for username in $(cat ${TEMP_USERS}) ; do
    if grep -q "^${username}:" ${PASSWD_BAK} ; then
      grep "^${username}:" ${PASSWD_BAK} >> ${UNSORTED_PASSWD}
    else
      error_nouser ${username}
    fi
  done
  sort -t: -k3 < ${UNSORTED_PASSWD} > ${T_PASSWD}
  rm -f ${UNSORTED_PASSWD}
}

# This shouldn't need the error checking in it, so here's hoping...
get_shadow_info() {
  # We'll use the sorted user list in T_PASSWD so that the shadow file
  # will be in the same order as the passwd file
  for username in $(cut -d: -f1 < ${T_PASSWD}); do
      grep "^${username}:" ${SHADOW_BAK} >> ${T_SHADOW}
  done
}

# Finally, this function will write out the contents of the temp files
# into more permanent files
write_additions() {
  cp -a ${T_PASSWD} ${PASSWD_ADD}
  cp -a ${T_SHADOW} ${SHADOW_ADD}
  printf "\n\tReview the contents of ${PASSWD_ADD} and ${SHADOW_ADD},
        and if they are what you expected, then you can simply append
        them to the existing /etc/passwd and /etc/shadow files.\n\n"
}

make_vars_secure
get_users
prune_users
get_passwd_info
get_shadow_info
write_additions