#! /bin/sh

# cvsd-buildroot - build a usable root-filesystem for cvsd
# Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2008, 2010 Arthur de Jong
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

# this script creates and updates
#  /bin
#     cvs
#  /lib
#     all libraries required by files in bin (auto)
#  /dev
#     null,zero
#  /etc
#     passwd
#  /tmp
#     (cleans up old files)

# fail on any problems
set -e
# report unset variables
set -u

# use hardcoded path to avoid trojans
PATH=/bin:/sbin:/usr/bin:/usr/sbin:/usr/pkg/bin:/usr/pkg/sbin
export PATH

# which binaries to install (use spaces as separator)
BINARIES="/usr/bin/cvs"

# where the cvsd configfile is located
CONFIGFILE="/usr/pkg/etc/cvsd.conf"

# path to use when looking for extra libraries
LIBPATH="/lib /usr/lib /usr/local/lib /usr/X11R6/lib /usr/lib/libc5-compat /lib/libc5-compat /usr/libexec"

if [ -f "/etc/ld.so.conf" ]
then
    # add paths from /etc/ld.so.conf to LIBPATH
    LIBPATH="$LIBPATH `find /etc/ld.so.conf* -type f | xargs cat | grep '^/'`"
fi

# which libraries to install (aside from the libraries needed by
# the specified libraries)
# for generic Linux:
EXTRALIBS="libnsl.so libnss_compat.so /lib/ld-linux.so.2"
# for some 64 bit Linux systems:
EXTRALIBS="$EXTRALIBS /lib64/ld-linux-x86-64.so.2 /lib64/tls/libnss_compat.so.2 /lib64/libnss_compat.so.2 /lib64/tls/libnss_files.so.2 /lib64/libnss_files.so.2"
# for multiarch systems
EXTRALIBS="$EXTRALIBS /lib/*/libnss_compat.so.2 /lib/*/libnss_files.so.2"
# for FreeBSD:
EXTRALIBS="$EXTRALIBS ld-elf.so"
# for Redhat 7.2:
EXTRALIBS="$EXTRALIBS libnss_compat.so.2 libnss_files.so.2"
# for OpenBSD:
EXTRALIBS="$EXTRALIBS /usr/libexec/ld.so"
# for NetBSD
EXTRALIBS="$EXTRALIBS /usr/libexec/ld.elf_so /libexec/ld.elf_so"
# for Solaris:
EXTRALIBS="$EXTRALIBS /usr/lib/ld.so.1 nss_files.so.1"

# users to take from system passwd and put in ROOT/etc/passwd
# (if they exist)
USERS="root nobody cvsd cvs"

# find the flavor of the echo command (stolen from configure)
case `echo "testing\c"; echo 1,2,3`,`echo -n testing; echo 1,2,3` in
  *c*,-n*) ECHO_N= ECHO_C='
' ;;
  *c*,*  ) ECHO_N=-n ECHO_C= ;;
  *)       ECHO_N= ECHO_C='\c' ;;
esac

# check command line parameter
if [ $# -ne 1 ] || echo "$1" | grep -v '^/' > /dev/null 2>&1
then
  echo "Usage: $0 DIRECTORY"
  echo "Create and populate a directory for use as a chroot jail for running cvsd in."
  echo "The directory should be specified as an absolute path."
  echo ""
  echo "Report bugs to <cvsd-users@lists.arthurdejong.org>."
  exit 1
fi

# where to make root filesystem
ROOT=$1

# check user id
if ( id -u > /dev/null 2>&1 && [ "`id -u`" != "0" ] ) || \
   ( /usr/xpg4/bin/id -u > /dev/null 2>&1 && [ "`/usr/xpg4/bin/id -u`" != "0" ] )
then
  echo "WARNING: you should probably run this as a ROOT user" >&2
fi

# set a reasonable umask for these sort of things
umask 022

# create dirs with right permissions
echo $ECHO_N "creating directory structure under $ROOT... $ECHO_C"
mkdir -p "$ROOT/bin" "$ROOT/lib" "$ROOT/dev" "$ROOT/etc" "$ROOT/usr" "$ROOT/tmp"
chmod 755 "$ROOT" "$ROOT/bin" "$ROOT/lib" "$ROOT/dev" "$ROOT/etc" "$ROOT/usr"
chmod 1777 "$ROOT/tmp"
# create $ROOT/usr/lib for some systems with fixed linker paths
ls "$ROOT/usr/lib" > /dev/null 2>&1 || \
  ( cd "$ROOT/usr" ; ln -s ../lib ./lib )
# also for bin
ls "$ROOT/usr/bin" > /dev/null 2>&1 || \
  ( cd "$ROOT/usr" ; ln -s ../bin ./bin )
# also create $ROOT/usr/libexec on systems that have such a thing
if ls /usr/libexec > /dev/null 2>&1
then
  ls "$ROOT/usr/libexec" > /dev/null 2>&1 || \
    ( cd "$ROOT/usr" ; ln -s ../lib ./libexec )
fi
# also create $ROOT/libexec on systems that have such a thing
if ls /libexec > /dev/null 2>&1
then
  ls "$ROOT/libexec" > /dev/null 2>&1 || \
    ( cd "$ROOT/" ; ln -s lib ./libexec )
fi
# remove old $ROOT/usr/lib64 and $ROOT/lib64 symlinks
[ -h "$ROOT/usr/lib64" ] && rm -f "$ROOT/usr/lib64"
[ -h "$ROOT/lib64" ] && rm -f "$ROOT/lib64"
# also create $ROOT/usr/lib64 on systems that have such a thing
if ls /usr/lib64 > /dev/null 2>&1
then
  ls "$ROOT/usr/lib64" > /dev/null 2>&1 || \
    ( cd "$ROOT/usr" ; ln -s ../lib64 ./lib64 ;
      mkdir -p "$ROOT/lib64" ; chmod 755 "$ROOT/lib64" )
fi
# also create $ROOT/lib64 on systems that have such a thing
if ls /lib64 > /dev/null 2>&1
then
  ls "$ROOT/lib64" > /dev/null 2>&1 || \
    ( mkdir -p "$ROOT/lib64" ; chmod 755 "$ROOT/lib64" )
fi
# remove $ROOT/lib/tls if it's no longer outside the chroot
if ls "$ROOT/lib/tls" >/dev/null 2>&1
then
  ls /lib/tls >/dev/null 2>&1 || ls /usr/lib/tls >/dev/null 2>&1 || \
    ls "$ROOT/lib/tls.movedbycvsd" >/dev/null 2>&1 || \
      ( mv "$ROOT/lib/tls" "$ROOT/lib/tls.movedbycvsd" && \
        chmod -R go-rwx "$ROOT/lib/tls.movedbycvsd" )
fi
# remove $ROOT/lib64/tls if it's no longer outside the chroot
if ls "$ROOT/lib64/tls" >/dev/null 2>&1
then
  ls /lib64/tls >/dev/null 2>&1 || ls /usr/lib64/tls >/dev/null 2>&1 || \
    ls "$ROOT/lib64/tls.movedbycvsd" >/dev/null 2>&1 || \
      ( mv "$ROOT/lib64/tls" "$ROOT/lib64/tls.movedbycvsd" && \
        chmod -R go-rwx "$ROOT/lib64/tls.movedbycvsd" )
fi
echo "done."

# populate /bin
echo $ECHO_N "installing binaries...$ECHO_C"
for i in $BINARIES
do
  cp "$i" "$ROOT/bin"
  chmod 755 "$ROOT/bin/`basename $i`"
  echo $ECHO_N " `basename $i`$ECHO_C"
done
echo "."

# report files in bin that don't belong there
for i in $ROOT/bin/*
do
  found=0
  for j in $BINARIES
  do
    if [ `basename $i` = `basename $j` ]
    then
      found=1
    fi
  done
  if [ $found -eq 0 ]
  then
    echo "WARNING: extra (unknown) file found: $i" >&2
  fi
done

# gather all to-be-installed libraries here
LIBRARIES=""

# find specified libraries that don't show up with ldd
echo $ECHO_N "looking for non-linked system libraries... $ECHO_C"
for i in $EXTRALIBS
do
  found=`( ( ls "$i".* "$i"* || true
             for j in $LIBPATH
             do
               ls "$j/$i".* "$j/$i"* || true
             done ) | head -1 ) 2> /dev/null`
  if [ -n "$found" ]
  then
    LIBRARIES="$LIBRARIES $found"
  fi
done
echo "done."

# expression to parse output of ldd
sedexp='s|^.* =>[^/]*\(/[^ ]*\).*$|\1|p;s|^[^A-Za-z0-9./][^A-Za-z0-9./]*\(/[^ ]*\).*$|\1|p'
# figure out libraries for extra to be installed libraries
LIBARIES="$LIBRARIES `ldd $LIBRARIES 2> /dev/null | sed -n "$sedexp"`"
# figure out libraries used by stuff in bin directory
LIBARIES="$LIBRARIES `ldd $ROOT/bin/* 2> /dev/null | sed -n "$sedexp"`"
# filter out double entries
LIBRARIES="`( for i in $LIBRARIES ; do echo $i ; done ) | sort -u`"

# install needed libraries
echo $ECHO_N "installing libraries... $ECHO_C"
for i in $LIBARIES
do
  # create (sub)directory if it doesn't yet exist
  d=`dirname "$i"`
  [ -d "$ROOT$d" ] || ( mkdir -p "$ROOT$d" ; chmod 755 "$ROOT$d" )
  # copy the library
  cp "$i" "$ROOT$i"
  chmod 755 "$ROOT$i"
  # just log it
done
echo "done."

# checking for unknown libraries
# TODO: make these tests better
for i in `find $ROOT/lib* -type f`
do
  found=0
  for j in $LIBARIES
  do
    if [ `basename $i` = `basename $j` ]
    then
      found=1
    fi
  done
  if [ $found -eq 0 ]
  then
    echo "WARNING: extra (unknown) file found: $i" >&2
  fi
done

# populate /dev (need root privileges for this)
echo $ECHO_N "creating $ROOT/dev devices... $ECHO_C"
DEVICES="null zero"
MISSINGDEVS=""
for d in $DEVICES
do
  if [ -r "$ROOT/dev/$d" ]
  then
    :
  else
    MISSINGDEVS="$MISSINGDEVS $d"
  fi
done
if [ -n "`echo $MISSINGDEVS`" ]
then
  if (cd /dev ; tar chpf - $MISSINGDEVS) | \
     ( cd "$ROOT/dev" ; tar xpf - > /dev/null 2>&1 )
  then
    # check if we can use the devices
    if ( echo TEST > "$ROOT/dev/null" && \
         echo TEST > "$ROOT/dev/zero" )  2> /dev/null
    then
      echo "done."
    else
      echo "FAILED (unable to use devices)"
    fi
  else
    echo "FAILED."
  fi
else
  echo "already there."
fi

# update /etc/passwd
echo $ECHO_N "adding users to $ROOT/etc/passwd...$ECHO_C"
for i in $USERS
do
  # find user from /etc/passwd or getent
  PWL="`getent passwd $i 2>/dev/null || grep '^'$i: /etc/passwd || true`" 2> /dev/null
  if [ "x$PWL" != "x" ]
  then
    if grep "^$i:" "$ROOT/etc/passwd" > /dev/null 2>&1
    then
      :
    else
      # take uname:x:uid:gid:fullname:/:shell from /etc/passwd
      echo "$PWL" | \
        sed -n \
        's|^'$i':[^:]*:\([^:]*\):\([^:]*\):\([^:]*\):[^:]*:\([^:]*\)$|'$i':x:\1:\2:\3:/:\4|p' \
        >> "$ROOT/etc/passwd"
      echo $ECHO_N " $i$ECHO_C"
    fi
  fi
done
echo "."

# check users in $ROOT/etc/passwd
save_IFS="$IFS"; IFS=":"
cat "$ROOT/etc/passwd" | while read i pass uid gid fullname home shell
do
  IFS="$save_IFS"
  # find user from /etc/passwd or getent
  PWL="`getent passwd $i 2>/dev/null || grep '^'$i: /etc/passwd || true`" 2> /dev/null
  if [ "x$PWL" != "x" ]
  then
    # check that uid and gid match
    echo "$PWL" | grep "^$i:[^:]*:$uid:$gid:" > /dev/null 2>&1 || \
      echo "WARNING: user $i in $ROOT/etc/passwd does not match the one in system passwd" >&2
  else
    echo "WARNING: user $i in $ROOT/etc/passwd does not exist in system passwd" >&2
  fi
  [ -d "$ROOT/$home" ] || \
    echo "WARNING: home directory of user $i in $ROOT/etc/passwd does not exist inside $ROOT" >&2
  IFS=":"
done
IFS="$save_IFS"

# check if all users in repositories are in $ROOT/etc/passwd
for repos in `find "$ROOT" \( -name tmp -prune \) -o \( -name 'lock*' -prune \) -o \( -name 'CVSROOT' -print \) 2> /dev/null`
do
  if [ -r "$repos/passwd" ]
  then
    sed -n 's/^[^:]*:[^:]*:\(.*\)$/\1/p;s/^\([^:]*\):[^:]*$/\1/p' < "$repos/passwd" \
      | while read usr
    do
      if grep "^$usr:" "$ROOT/etc/passwd" > /dev/null 2>&1
      then
        :
      else
        # find user from /etc/passwd or getent
        PWL="`getent passwd $usr 2>/dev/null || grep '^'$usr: /etc/passwd || true`" 2> /dev/null
        if [ "x$PWL" != "x" ]
        then
          echo "adding user $usr (referenced in $repos/passwd) to $ROOT/etc/passwd"
          # take uname:x:uid:gid:fullname:/:shell from /etc/passwd
          echo "$PWL" | \
            sed -n \
            's|^'$usr':[^:]*:\([^:]*\):\([^:]*\):\([^:]*\):[^:]*:\([^:]*\)$|'$usr':x:\1:\2:\3:/:\4|p' \
            >> "$ROOT/etc/passwd"
        else
          echo "WARNING: system user $usr is referenced in $repos/passwd but not in $ROOT/etc/passwd or system passwd" >&2
        fi
      fi
    done
  else
    echo "WARNING: no passwd file in $repos" >&2
  fi
done

# check if every user in a repository passwd file is mapped to cvsd
if [ -r "$CONFIGFILE" ]
then
  uid=`sed -n 's/^ *Uid *\([^ ]*\) *$/\1/p' < "$CONFIGFILE"`
  if [ "x$uid" != "x" ] && [ "x$uid" != "xroot" ] && [ "x$uid" != "x0" ]
  then
    for repos in `find "$ROOT" -name 'CVSROOT' 2> /dev/null`
    do
      if [ -r "$repos/passwd" ]
      then
        if sed 's/^[^:]*:[^:]*:'$uid'//' < "$repos/passwd" | \
           grep '^[^#].*$' > /dev/null 2> /dev/null
        then
          echo "WARNING: not all users in $repos/passwd are mapped to system user $uid" >&2
        fi
      fi
    done
  fi
fi

# for systems with strange password files (OpenBSD/NetBSD/FreeBSD)
if [ -r /etc/master.passwd ] && [ -r /etc/pwd.db ] && [ -x /usr/sbin/pwd_mkdb ]
then
  echo $ECHO_N "making $ROOT/etc/pwd.db...$ECHO_C"
  # convert /etc/passwd to /etc/master.passwd
  sed 's|\([^:]*\):\([^:]*\):\([^:]*\):\([^:]*\):\([^:]*\):\([^:]*\):\([^:]*\)|\1:\2:\3:\4::0:0:\5:\6:\7|' \
    < "$ROOT/etc/passwd" > "$ROOT/etc/master.passwd"
  # NetBSD expects -d to be the new root directory.
  /usr/sbin/pwd_mkdb -p -d "$ROOT/etc" "$ROOT/etc/master.passwd" 2>/dev/null || \
  /usr/sbin/pwd_mkdb -p -d "$ROOT" "$ROOT/etc/master.passwd" 2>/dev/null
  echo "done."
fi

# TODO: maybe create some /etc/group for systems that requires it (even OpenBSD doesn't)

# clean /tmp
TMPREAPER="`which tmpreaper 2> /dev/null || true`"
if [ -x "$TMPREAPER" ]
then
  echo $ECHO_N "cleaning $ROOT/tmp... $ECHO_C"
  $TMPREAPER 7d $ROOT/tmp
  echo "done."
fi

# create directories mentioned in CVSROOT/config:LockDir=...
for repos in `find "$ROOT" -name 'CVSROOT' 2> /dev/null`
do
  if [ -r "$repos/config" ]
  then
    sed -n 's/^ *LockDir *= *\([^ ]*\) *$/\1/p' < "$repos/config" \
      | while read lockdir
    do
      if [ -d "$ROOT/$lockdir" ]
      then
        :
      else
        echo $ECHO_N "creating $ROOT/$lockdir for lockfiles" $ECHO_C
        mkdir -p "$ROOT/$lockdir"
        chmod 1777 "$ROOT/$lockdir"
        echo "done."
      fi
    done
  fi
done

# change owner (need root privileges for this)
echo $ECHO_N "fixing ownership... $ECHO_C"
dirs="$ROOT/bin $ROOT/lib $ROOT/dev $ROOT/etc $ROOT/usr"
[ -d "$ROOT/lib64" ] && dirs="$dirs $ROOT/lib64"
if chown 0:0 "$ROOT" "$ROOT/tmp" > /dev/null 2>&1 && \
   chown -R 0:0 $dirs > /dev/null 2>&1
then
  echo "done."
else
  echo "FAILED."
fi

echo "chrooted system created in $ROOT"
echo "if your cvs binary changes (new version) you should rerun cvsd-buildroot"

exit 0
