#!/bin/bash

CHD=$1

if [ $# -lt 1 ]; then
    echo "Usage: sync-chr-users [chroot] [SURE]"
    exit 3
fi

if ! [ -d "$CHD/etc" ]; then
    echo "Chroot dir $CHD doesn't exist"
    exit 23
fi


echo "************************************"
echo "*** syncing chroot users to root ***"
echo "************************************"
if [ "$2" != "SURE" ]; then
    echo "*** TEST RUN *** TEST RUN *** TEST RUN *** TEST RUN *** TEST RUN *** TEST RUN ***"
fi

    PWF=$CHD/etc/passwd
    GRF=$CHD/etc/group

    if [ -f $PWF ]; then
	echo "*** $CHD ***"

	# check for users
	allusers=`cat $PWF |cut -d: -f1`
	for user in $allusers; do
	    pwline=`grep -e "^$user\:" $PWF`
	    uid=`echo "$pwline" |cut -d: -f3`
	    gid=`echo "$pwline" |cut -d: -f4`

	    rpwline=`grep -e "^$user\:" /etc/passwd`
	    ruid=`echo "$rpwline" |cut -d: -f3`
	    rgid=`echo "$rpwline" |cut -d: -f4`

	    if [ "x$ruid" == "x" ]; then
		echo "ERROR: User $user (in $CHD chroot) doesn't exist in root!"
		echo "Please create $user user in root and start again."
		exit 43
	    fi
	done

	#check for groups
	allgroups=`cat $GRF |cut -d: -f1`
	for group in $allgroups; do
	    grline=`grep -e "^$group\:" $GRF`
	    gid=`echo "$grline" |cut -d: -f3`

	    rgrline=`grep -e "^$group\:" /etc/group`
	    rgid=`echo "$rgrline" |cut -d: -f3`

	    if [ "x$rgid" == "x" ]; then
		echo "ERROR: Group $group (in $CHD chroot) doesn't exist in root!"
		echo "Please create $group group in root and start again."
		exit 45
	    fi
	done

	# do the sync
	pruid=""
	prgid=""
	#allusers=`cat $PWF |cut -d: -f1`
	for user in $allusers; do
	    pwline=`grep -e "^$user\:" $PWF`
	    uid=`echo "$pwline" |cut -d: -f3`
	    gid=`echo "$pwline" |cut -d: -f4`

	    rpwline=`grep -e "^$user\:" /etc/passwd`
	    ruid=`echo "$rpwline" |cut -d: -f3`
	    rgid=`echo "$rpwline" |cut -d: -f4`

	    tmpuid=50000
	    tmpgid=50000
	    let tmpuid=$ruid+50000
	    let tmpgid=$rgid+50000

	    # change uid and update passwd file
	    if [ "$uid" != "$ruid" ]; then
		echo "$user -> changing uid: $uid / r$ruid ($tmpuid)"
		find $CHD -mount -uid $uid
		if [ "$2" == "SURE" ]; then
		    find $CHD -mount -uid $uid -exec chown $tmpuid {} \;

		    echo "updating $PWF..."
		    cat $PWF | sed -e "s/\(^$user\:.*\:\)$uid\:/\1$tmpuid:/g" >$PWF-tmp
		    mv $PWF-tmp $PWF
		fi
		pruid="$pruid $ruid"
	    fi

	    # change gid and update passwd/group file
	    if [ "$gid" != "$rgid" ]; then
		echo "$user -> changing gid: $gid / r$rgid ($tmpgid)"
		find $CHD -mount -gid $gid
		if [ "$2" == "SURE" ]; then
		    find $CHD -mount -gid $gid -exec chgrp $tmpgid {} \;

		    echo "updating $PWF..."
		    cat $PWF | sed -e "s/\(^$user\:.*\:.*\:\)$gid\:/\1$tmpgid:/g" >$PWF-tmp
		    mv $PWF-tmp $PWF
		    echo "updating $GRF..."
		    cat $GRF | sed -e "s/\(^.*\:.*\:\)$gid\:/\1$tmpgid:/g" >$GRF-tmp
		    mv $GRF-tmp $GRF
		fi
		prgid="$prgid $rgid"
	    fi
	    
	done

	# change groups that are not connected to uid
	allgroups=`cat $GRF |cut -d: -f1`
	skipgroups="$prgid"
	for group in $allgroups; do

	    grline=`grep -e "^$group\:" $GRF`
	    gid=`echo "$grline" |cut -d: -f3`

	    rgrline=`grep -e "^$group\:" /etc/group`
	    rgid=`echo "$rgrline" |cut -d: -f3`

	    tmpgid=50000
	    let tmpgid=$rgid+50000

	    skipg="0"
	    for prg in $skipgroups; do
		if [ "$rgid" == "$prg" ]; then skipg="1"; fi
	    done

	    if [ "$skipg" == "0" ]; then

		if [ "$gid" != "$rgid" ]; then
		    echo "group $group -> changing gid: $gid / r$rgid  ($tmpgid)"
		    find $CHD -mount -gid $gid
		    if [ "$2" == "SURE" ]; then
			find $CHD -mount -gid $gid -exec chgrp $tmpgid {} \;
		    fi
		    prgid="$prgid $rgid"
		fi

		if [ "$gid" != "$rgid" ]; then
		    if [ "$2" == "SURE" ]; then
			echo "updating $PWF..."
			cat $PWF | sed -e "s/\(^.*\:.*\:.*\:\)$gid\:/\1$tmpgid:/g" >$PWF-tmp
			mv $PWF-tmp $PWF
			echo "updating $GRF..."
			cat $GRF | sed -e "s/\(^$group\:.*\:\)$gid\:/\1$tmpgid:/g" >$GRF-tmp
			mv $GRF-tmp $GRF
		    fi
		fi
	    fi

	done


	#finalize uids
	if [ "$2" == "SURE" ]; then
	    for uid in $pruid; do
		let tmpuid=$uid+50000
		echo "finalizing uid: $uid ($tmpuid)"
		find $CHD -mount -uid $tmpuid
		find $CHD -mount -uid $tmpuid -exec chown $uid {} \;

		echo "finalizing $PWF stage 1..."
		cat $PWF | sed -e "s/\(^.*\:.*\:\)$tmpuid\:/\1$uid:/g" >$PWF-tmp
		mv $PWF-tmp $PWF
	    done
	    for gid in $prgid; do
		let tmpgid=$gid+50000
		echo "finalizing gid: $gid ($tmpgid)"
		find $CHD -mount -gid $tmpgid
		find $CHD -mount -gid $tmpgid -exec chgrp $gid {} \;

		echo "finalizing $PWF stage 2..."
		cat $PWF | sed -e "s/\(^.*\:.*\:.*\:\)$tmpgid\:/\1$gid:/g" >$PWF-tmp
		mv $PWF-tmp $PWF
		echo "finalizing $GRF..."
	        cat $GRF | sed -e "s/\(^.*\:.*\:\)$tmpgid\:/\1$gid:/g" >$GRF-tmp
		mv $GRF-tmp $GRF
	    done
	fi
    fi


if [ "$2" != "SURE" ]; then
    echo "************************************************************************************"
    echo "NOTE: I haven't done anything yet."
    echo "WARNING! This script will sync all user uids and gids in chroots to the root system."
    echo "If you are sure, type SURE as parameter"
    echo "Usage: sync-chr-users [chroot] [SURE]"
    exit 7
fi