File: netscript-ipfilter

package info (click to toggle)
netscript-2.4 5.5.5%2Bnmu3
  • links: PTS
  • area: main
  • in suites: forky, sid, trixie
  • size: 460 kB
  • sloc: sh: 2,166; makefile: 86
file content (1014 lines) | stat: -rwxr-xr-x 20,875 bytes parent folder | download | duplicates (5)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
#!/bin/bash

#
# LRP/Debian network configuration system
#
# Ring a ding ding, my dang a lang dong	   Dave 'Kill a Cop' Cinege   GPL2
# Ding Dong Dell, Pussy's in the well      Matthew 'Network Cowboy' Grant GPL2

# 
# start)
# Depending on the auto config portions in /etc/network.conf, it auto-
# generates hosts, resolv.conf, sets the hostname, starts up interfaces,
# configures the IP filter/firewall and sets up routes (not necessarily
# in that order). 
# 
# stop)
# brings down all interfaces listed in /proc/net/dev, and their associated
# routes. Flushes all rules for iptables.
#

# bail out if we are not root
if [ "`id -un`" != "root" ] ; then
	echo 1>&2
	echo "  `basename $0`: you must be root to run this command." 1>&2
	echo 1>&2
	exit 1
fi

TARGET_KERNEL1="2.4"
TARGET_KERNEL2="2.6"
TARGET_KERNEL3="3"

#DEBUG=1

SP='   '

qt () { "$@" >/dev/null 2>&1 ; }
vb () { "$@" ; }
source () { . $1 ; }
basename () { echo "${1##*/}"; }

BANNER="# This file was generated by $0. It may be overwritten!"


#Default safe settings
VERBOSE=YES
IPV6_MODULE=NO
IPV4_FWDING_KERNEL=NO
IPV6_FWDING_KERNEL=NO
IP_FILTER_KERNEL=PACKET
IF_AUTO="eth0"
IPV4_DISABLE=NO
IPV6_DISABLE=NO
BASE_MODPATH="/lib/modules/`uname -r`/kernel"
MODPATH="${BASE_MODPATH}/net"
KERN_VERSION=`uname -r | cut -d . -f 1,2`
if echo "$KERN_VERSION" | grep '^[3-9]\..*' -q; then
	KERN_VERSION='3'
fi
[ "$KERN_VERSION" = "$TARGET_KERNEL1" ] && MODEXT="o"
[ "$KERN_VERSION" = "$TARGET_KERNEL2" ] && MODEXT="ko"
[ "$KERN_VERSION" = "$TARGET_KERNEL3" ] && MODEXT="ko"
NETFILTER_CONF="/etc/netscript"
IPTBL_FILE="$NETFILTER_CONF/iptables"
IPTBL_FILE_BACKUP="$IPTBL_FILE.backup"
IP6TBL_FILE="$NETFILTER_CONF/ip6tables"
IP6TBL_FILE_BACKUP="$IP6TBL_FILE.backup"
# test for OpenWRT
if type -f iptables | grep -q '/usr/sbin'; then
	IPTBL_PREFIX="/usr/sbin"
else
	IPTBL_PREFIX="/sbin"
fi
IPTBL="$IPTBL_PREFIX/iptables"
IPTBL_RESTORE="$IPTBL_PREFIX/iptables-restore"
IPTBL_SAVE="$IPTBL_PREFIX/iptables-save"
IP6TBL="$IPTBL_PREFIX/ip6tables"
IP6TBL_RESTORE="$IPTBL_PREFIX/ip6tables-restore"
IP6TBL_SAVE="$IPTBL_PREFIX/ip6tables-save"
IPTBL_V4PROC="/proc/net/ip_tables_names"
IPTBL_V6PROC="/proc/net/ip6_tables_names"
IPV4_PROC="/proc/sys/net/ipv4"
IPV6_PROC="/proc/sys/net/ipv6"
IPFWD_V4PROC="${IPV4_PROC}/ip_forward"
IPFWD_V6PROC="${IPV6_PROC}/conf/all/forwarding"
IPV6_DEFAULT_PREFIX=default
DEFAULT_METRIC=999999999
BACKUP_LEVELS=2
IF_DEFAULT_IPV6_DISABLE="NO"

#==============================================================================#

# Read in configuration files 
# 	- these ones can be changed by users
[ -f $NETFILTER_CONF/network.conf ] \
	&& source $NETFILTER_CONF/network.conf
IPFILTER=0
[ -f $NETFILTER_CONF/ipfilter.conf ] \
	&& source $NETFILTER_CONF/ipfilter.conf && IPFILTER=1
[ -f $NETFILTER_CONF/srvfilter.conf ] \
	&& source $NETFILTER_CONF/srvfilter.conf

[ "$DEBUG" ] && qt () { "$@" ; }
[ "$VERBOSE" = "NO" ] && vb () { qt "$@" ; }


[ -f /proc/net/ip_fwchains ] && IPCHAINS=1
[ -f /proc/net/ip_masq/autofw ] && IPAUTOFW=1
[ -f /proc/net/ip_masq/portfw ] && IPPORTFW=1
[ -f /proc/net/ip_masq/mfw ] && IPMFW=1

# translate old values for compatibility
if [ -n "$IPFWDING_KERNEL" ]; then
	IPV4_FWDING_KERNEL="$IPFWDING_KERNEL"
fi
# Setup stuff for IPv6
IPV6_KRNL=0
[ -d $IPV6_PROC ] && IPV6_KRNL=1

#############################################################################
# Code to set up function lists for filtering
#############################################################################

get_fns () {
	local STR="s/^.* ${1}\([^ ]\+\)$/\1/"
	if [ -n "$BASH_VERSION" ]; then
		declare -F | grep $1 | sed -e "$STR"
	else
		hash | grep "^function $1" | sed -e "$STR"
	fi
}

for FN in `get_fns ipf4_`; do
	if [ -z "$IPF4_FNS" ]; then
		IPF4_FNS="$FN"
	else
		IPF4_FNS="${IPF4_FNS}|$FN"
	fi
done; unset FN

for FN in `get_fns ipf6_`; do
	if [ -z "$IPF6_FNS" ]; then
		IPF6_FNS="$FN"
	else
		IPF6_FNS="${IPF6_FNS}|$FN"
	fi
done; unset FN

###############################################################################
#IP kernel option loading for global kernel switches
###############################################################################
read_sysctl () {
        local PROCFILE PROCVAL COMMENT ANS

	while read PROCFILE PROCVAL COMMENT; do
		if [ -z "$PROCFILE" -o -z "$PROCVAL" ]; then
			continue
		fi
	
		if [ "$PROCFILE"  = "#" -o "$PROCVAL" = "#" ]; then
			continue
		fi
		
		case "$PROCVAL" in
		YES|Yes|yes)
			PROCVAL=1
			;;
		NO|No|no)
			PROCVAL=0
			;;
		esac

		[ ! -f $1/$PROCFILE ] && continue

		echo $PROCVAL > $1/$PROCFILE
	done

}

read_gbl_sysctl () {

	echo "$NET_GLOBAL_SYSCTL" | read_sysctl /proc/sys/net
	
	return 0
}


###############################################################################
#IP Forwarding configuration
###############################################################################
start_auto_ipkrnlswch () {
    	local DIR
    
	# read in the global sysctl settings
	#read_gbl_sysctl

	# Turn on global RP filter switch - this is ANDed with 
	# the per interface ones
	#echo 1 > ${IPV4_PROC}/conf/all/rp_filter
	# Fix the Shared Media Mess
	#echo 0 > ${IPV4_PROC}/conf/all/shared_media
	#echo 0 > ${IPV4_PROC}/conf/default/shared_media


	if [ "$IPV4_FWDING_KERNEL" = "YES" ]; then
		vb echo -n "Enabling IPv4 packet forwarding..."
		echo "1" >$IPFWD_V4PROC && vb echo "done."
	elif [ "$IPV4_FWDING_KERNEL" != "FILTER_ON" ]; then
		vb echo -n "Disabling IPv4 packet forwarding..."
		echo "0" >$IPFWD_V4PROC && vb echo "done."
	fi 

	# IPv6  
	if [ $IPV6_KRNL -lt 1 ]; then
		return 0
	fi
	
	# Most hardened servers and routers need defaults like these
	# for interface host mode
	#for DIR in ${IPV6_PROC}/conf/*; do
	#	# Don't allow ICMP redirect by default
	#
	#echo 0 > $DIR/accept_redirects
	#done

	# This is here just to do the printing when IPv6 IS disabled.
	case "$IPV6_DISABLE" in
	YES|Yes|yes)
		vb echo -n "Disabling IPv6 protocol..." 
		ifv6_setproc all disable_ipv6 "$IPV6_DISABLE" && echo "done."
		;;
	*)
		ifv6_setproc all disable_ipv6 "$IPV6_DISABLE"
		;;
	esac

	# Set this flag as required for creation of dynamic bridged
	# interfaces
	#ifv6_setproc default disable_ipv6 "$IF_DEFAULT_IPV6_DISABLE"

	if [ "$IPV6_FWDING_KERNEL" = "YES" ]; then
		vb echo -n "Enabling IPv6 packet forwarding..." 
		echo "1" >$IPFWD_V6PROC && vb echo "done."
	elif [ "$IPV6_FWDING_KERNEL" != "FILTER_ON" ]; then
		vb echo -n "Disabling IPv6 packet forwarding..." 
		echo "0" >$IPFWD_V6PROC && vb echo "done."
	fi 

}

##############################################################################
# Functions to set 2.4 kernel interface parameters
# ifv4_setproc (<interface> <file> YES|NO
# ifv6_setproc (<interface> <file> YES|NO
##############################################################################
ifv4_setproc () {
	if [ -z "$3" ]; then
		return 0;
	fi

	[ ! -f ${IPV4_PROC}/conf/$1/$2 ] && return 1

	case "$3" in 
	YES|Yes|yes)
		echo 1 > ${IPV4_PROC}/conf/$1/$2
		return 0;
		;;
	NO|No|no)
		echo 0 > ${IPV4_PROC}/conf/$1/$2
		return 0;
		;;
	*)
		if echo $3 | grep -q '^[0-9]\+$'; then
			echo $3 > ${IPV4_PROC}/conf/$1/$2
			return 0
		fi

		return 1;
		;;
	esac
	
	return 0;
	
}

ifv6_setproc () {
	if [ -z "$3" ]; then
		return 0;
	fi

	[ $IPV6_KRNL -lt 1 ] && return 1 
	[ ! -f ${IPV6_PROC}/conf/$1/$2 ] && return 1

	case "$3" in 
	YES|Yes|yes)
		echo 1 > ${IPV6_PROC}/conf/$1/$2
		return 0;
		;;
	NO|No|no)
		echo 0 > ${IPV6_PROC}/conf/$1/$2
		return 0;
		;;
	*)
		if echo $3 | grep -q '^[0-9]\+$'; then
			echo $3 > ${IPV6_PROC}/conf/$1/$2
			return 0
		fi
		
		return 1;
		;;
	esac
	
	return 0;
	
}


##############################################################################
# checkarg() a function to check interface arguments
##############################################################################
checkarg() {
    eval "case \"$*\" in
        $IFLIST)
            ;;
        *)
            echo \"Usage: `basename $0` ifup|ifdown|ifqos|ifreload\" 
	    echo \"       ${SP} {$IFLIST}\"
            exit 1
            ;;
         esac"
}


##############################################################################
# functions to handle filter stuff
##############################################################################

#
# backup_rotate <filename> <maxlevel>
#
backup_rotate () {
        local MAX="$2"
        [ $MAX -lt 2 ] && MAX=2
        local COUNT=$(($MAX - 1))
        local PREV="$MAX"
        while [ $COUNT -gt 0 ]; do
                [ -f "${1}.${COUNT}" ] && mv "${1}.${COUNT}" "${1}.${PREV}"
                PREV=$COUNT
                COUNT=$(( $COUNT - 1 ))
        done
        [ -f "$1" ] && mv "$1" "${1}.1"
	return 0
}

ipv4filter_kernfwd () {
	local OVERRIDE="$2"

	if [ "$OVERRIDE" != "YES" -a "$OVERRIDE" != "Yes" \
		-a "$OVERRIDE" != "yes" \
		-a  "$IPV4_FWDING_KERNEL" != "FILTER_ON" ]; then
		return 0;
    	fi
    
	case $1 in 
	on)
		vb echo -n "Enabling IPv4 packet forwarding..."
		echo "1" >$IPFWD_V4PROC \
			&& vb echo "done."
		;;
	off)
		vb echo -n "Disabling IPv4 packet forwarding..."
		echo "0" >$IPFWD_V4PROC \
			&& vb echo "done."
	    	;;
	*)
		echo "AAARGGHH - wrong argument given to ipv4filter_kernfwd: $1"
		exit 1
		;;
	esac
}

# Check and see if filtering and mangling are available
ipv4filter_check () {
	local TBL MANGLE FILTER
	MANGLE=0
	FILTER=0

	[ ! -f "$IPTBL_V4PROC" ] && return 1

	for TBL in `cat $IPTBL_V4PROC`; do
		case $TBL in
		mangle)
			MANGLE=1
			;;
		filter)
			FILTER=1
			;;
		esac
	done

	if [ $MANGLE -ne 1 -a $FILTER -ne 1 ]; then
		return 1
	fi

	return 0
}

# A function to flush the filters (for internal use)
ipv4filter_flush  () {
	local TBL

	# Flush the IPV4 filters out, and user defined chains
	[ ! -f $IPTBL_V4PROC ] && return 0
	for TBL in `cat $IPTBL_V4PROC`; do
		if [ "$TBL" = "$1" ]; then
			continue
		fi
		$IPTBL -t $TBL -F
		$IPTBL -t $TBL -X
	done

	return 0
}

ipv4filter_policy () {
	local TBL

	[ ! -f $IPTBL_V4PROC ] && return 0
	for TBL in `cat $IPTBL_V4PROC`; do
		if [ "$TBL" = "$2" ]; then
			continue
		fi

		case $TBL in
		mangle)
			$IPTBL -t $TBL -P PREROUTING $1
			$IPTBL -t $TBL -P OUTPUT $1
			;;
		filter)
			$IPTBL -t $TBL -P INPUT $1
			$IPTBL -t $TBL -P FORWARD $1
			$IPTBL -t $TBL -P OUTPUT $1
			;;
		nat)
			$IPTBL -t $TBL -P PREROUTING $1
			$IPTBL -t $TBL -P POSTROUTING $1
			$IPTBL -t $TBL -P OUTPUT $1
			;;
		rawpost)
			$IPTBL -t $TBL -P POSTROUTING $1
			;;
		raw)	
			$IPTBL -t $TBL -P PREROUTING $1
			$IPTBL -t $TBL -P OUTPUT $1
			;;
		security)
			$IPTBL -t $TBL -P INPUT $1
			$IPTBL -t $TBL -P FORWARD $1
			$IPTBL -t $TBL -P OUTPUT $1
			;;
		esac
	done

	return 0
}
				
# function to set the filter default policies
ipv4filter_clear () { 

	ipv4filter_flush $1

	ipv4filter_policy ACCEPT $1

	return 0	    

}

# Selects basic filter type configuration function
ipv4filter_iptbl_cfg () {
	if ! ipv4filter_check && ! $IPTBL -L &> /dev/null; then
		echo 
		echo "IPv4 filters: netfilter kernel modules not present." 
		echo
		return 1
	fi

	if [ ! -f $1 ] ; then
		echo
		echo "IPv4 filters: no $1 file."
		echo
		return 1
	fi
	echo -n "Loading IPv4 filters..." 
	if $IPTBL_RESTORE < $1; then
		ipf4_laptopfw
		vb echo "done."
		ipv4filter_kernfwd on
	else
		return 1
	fi

	return 0

}


ipv4filter_iptbl_save () {
	local OLD_UMASK
	
	if ! ipv4filter_check; then
		echo 
		echo "IPv4 filters: netfilter kernel modules not loaded." 
		echo
		return 1
	fi
	
	echo -n "Saving IPv4 filters..."
	backup_rotate "$IPTBL_FILE" "$BACKUP_LEVELS"
	OLD_UMASK=`umask`
	umask 0277
	if $IPTBL_SAVE > $IPTBL_FILE; then
		umask $OLD_UMASK
		chmod 0400 $IPTBL_FILE
		vb echo "done."
	else
		umask $OLD_UMASK
		vb echo
		return 1
	fi 

	vb echo
	return 0
}

# Some functions to handle Protocol IP Port tuples

ipfilter_echoParam () {
	local format="$1"
	local IFS='_'
	set -- $2
	eval "echo \"$format\""
}
	
ipfilter_echoIpPort () {
	local format1="$1"
	local format2="$2"
	local testpar="$3"
	local IFS='_'
	set -- $4
	eval "echo -n \"$format1\""
	eval "if [ -n \"$testpar\" ]; then
		echo \" $format2\"
	fi"
}

ipv4filter_exec () {
	local RES
	
	if ! ipv4filter_check && ! $IPTBL -L &> /dev/null; then
		echo 
		echo "IPv4 filters: netfilter kernel modules not present." 
		echo
		return 1
	fi

	local FN="$1"
	shift
	eval "case \"$FN\" in
		$IPF4_FNS)
			case \$1 in 
			-r|remove)
				vb echo -n \"Removing IPv4 filter $FN...\"
				;;
			*)
				vb echo -n \"Loading IPv4 filter $FN...\"
				;;
			esac
			if ipf4_${FN} $*; then 	
				echo \"done.\"
				exit 0
			fi
			exit 1
			;;
		*)
    			echo \"       `basename $0` ipfilter exec $IPF4_FNS\"
			echo \"                              [chain p1 p2 ...]\"
    			exit 1
			;;
		esac"

	return 0
}


ipv4filter_cmd () {
	
	if [ "$KERN_VERSION" != "$TARGET_KERNEL1" \
		-a "$KERN_VERSION" != "$TARGET_KERNEL2" \
		-a "$KERN_VERSION" != "$TARGET_KERNEL3" ] ; then
		echo
		echo "IPv4 filters: kernel not version ${TARGET_KERNEL1}.x, ${TARGET_KERNEL2}.x, or ${TARGET_KERNEL3}.x."
		if [ "$IPV4_FWDING_KERNEL" = "FILTER_ON" ]; then
			# Keep the output pretty..
			echo
		fi
		ipv4filter_kernfwd off
		echo
		return 1
	fi
	if ! [ -x $IPTBL ] ; then
		echo
		echo "IPv4 filters: $IPTBL not found."
		echo
		return 1
	fi
	case $1 in
	load|reload|restart|reset)
		ipv4filter_iptbl_cfg $IPTBL_FILE
    		;;
	usebackup)
		local BKUP_NUM=1
    		[ -n "$2" ] && BKUP_NUM="$2"
		ipv4filter_iptbl_cfg "${IPTBL_FILE}.${BKUP_NUM}"
		;;
	save)
		ipv4filter_iptbl_save
    		;;
	clear|flush)
		ipv4filter_kernfwd off
 		vb echo -n "Flushing IPv4 filters..."
 		ipv4filter_clear
    		vb echo "done."
    		;;
	exec)
		shift
		ipv4filter_exec $*
		;;
	forward|fwd)
		ipv4filter_kernfwd on yes
		;;
	noforward|nofwd)
		ipv4filter_kernfwd off yes
		;;
	
	*)
		echo "Usage: `basename $0` ipfilter load|clear|flush|fwd|nofwd|reload|save"
		echo "                              usebackup [backup-number]"
		echo "       `basename $0` ipfilter exec $IPF4_FNS"
		echo "                              [chain p1 p2 ...]"
		exit 1
		;;
	esac
}

# IPv6 filters

ipv6filter_kernfwd () {
	local OVERRIDE="$2"

	if [ "$OVERRIDE" != "YES" -a "$OVERRIDE" != "Yes" \
		-a "$OVERRIDE" != "yes" \
		-a  "$IPV6_FWDING_KERNEL" != "FILTER_ON" ]; then
		return 0;
    	fi
    
	case $1 in 
	on)
		vb echo -n "Enabling IPv6 packet forwarding..." 
		echo "1" >$IPFWD_V6PROC \
			&& vb echo "done."
		;;
	off)
		vb echo -n "Disabling IPv6 packet forwarding..."
		echo "0" >$IPFWD_V6PROC \
			&& vb echo "done."
	    	;;
	*)
		echo "AAARGGHH - wrong argument given to ipv6filter_kernfwd: $1"
		exit 1
		;;
	esac
}

# Check and see if filtering and mangling are available
ipv6filter_check () {
	local TBL MANGLE FILTER
	MANGLE=0
	FILTER=0

	[ ! -f "$IPTBL_V6PROC" ] && return 1

	for TBL in `cat $IPTBL_V6PROC`; do
		case $TBL in
		mangle)
			MANGLE=1
			;;
		filter)
			FILTER=1
			;;
		esac
	done

	if [ $MANGLE -ne 1 -a $FILTER -ne 1 ]; then
		return 1
	fi

	return 0
}


# A function to flush the filters (for internal use)
ipv6filter_flush  () {
	local TBL

	# Flush the IPV6 filters out, and user defined chains
	[ ! -f $IPTBL_V6PROC ] && return 0
	for TBL in `cat $IPTBL_V6PROC`; do
		if [ "$TBL" = "$1" ]; then
			continue
		fi
		$IP6TBL -t $TBL -F
		$IP6TBL -t $TBL -X
	done

	return 0
}

ipv6filter_policy () {
	local TBL

	[ ! -f $IPTBL_V6PROC ] && return 0
	for TBL in `cat $IPTBL_V6PROC`; do
		if [ "$TBL" = "$2" ]; then
			continue
		fi

		case $TBL in
		mangle)
			$IP6TBL -t $TBL -P PREROUTING $1
			$IP6TBL -t $TBL -P OUTPUT $1
			;;
		filter)
			$IP6TBL -t $TBL -P INPUT $1
			$IP6TBL -t $TBL -P FORWARD $1
			$IP6TBL -t $TBL -P OUTPUT $1
			;;
		nat)
			$IP6TBL -t $TBL -P PREROUTING $1
			$IP6TBL -t $TBL -P POSTROUTING $1
			$IP6TBL -t $TBL -P OUTPUT $1
			;;
		esac
	done

	return 0
}
				
# function to set the filter default policies
ipv6filter_clear () { 

	ipv6filter_flush $1

	ipv6filter_policy ACCEPT $1

	return 0	    

}

# Selects basic filter type configuration function
ipv6filter_iptbl_cfg () {
	if ! ipv6filter_check && ! $IP6TBL -L &> /dev/null; then
		echo 
		echo "IPv6 filters: netfilter kernel modules not present." 
		echo
		return 1
	fi

	if [ ! -f $1 ] ; then
		echo
		echo "IPv6 filters: no $1 file."
		echo
		return 1
	fi
	echo -n "Loading IPv6 filters..." 
	if $IP6TBL_RESTORE < $1; then
		ipf6_laptopfw
		vb echo "done."
		ipv6filter_kernfwd on
	else
		return 1
	fi

	return 0

}

ipv6filter_iptbl_save () {
	local OLD_UMASK

	if ! ipv6filter_check; then
		echo 
		echo "IPv6 filters: netfilter kernel modules not loaded." 
		echo
		return 1
	fi

	echo -n "Saving IPv6 filters..."
	backup_rotate "$IP6TBL_FILE" "$BACKUP_LEVELS"
	OLD_UMASK=`umask`
	umask 0277
	if $IP6TBL_SAVE > $IP6TBL_FILE; then
		umask $OLD_UMASK
		chmod 0400 $IP6TBL_FILE
		vb echo "done."
	else
		umask $OLD_UMASK
		vb echo
		return 1
	fi 

	vb echo
	return 0
}

ipv6filter_exec () {
	local RES
	
	if ! ipv6filter_check && ! $IP6TBL -L &> /dev/null; then
		echo 
		echo "IPv6 filters: netfilter kernel modules not present." 
		echo
		return 1
	fi

	local FN="$1"
	shift
	eval "case \"$FN\" in
		$IPF6_FNS)
			case \$1 in 
			-r|remove)
				vb echo -n \"Removing IPv6 filter $FN...\"
				;;
			*)
				vb echo -n \"Loading IPv6 filter $FN...\"
				;;
			esac
			if ipf6_${FN} $*; then 	
				echo \"done.\"
				exit 0
			fi
			exit 1
			;;
		*)
    			echo \"       `basename $0` ip6filter exec $IPF6_FNS\"
			echo \"                              [chain p1 p2 ...]\"
    			exit 1
			;;
		esac"


	return 0
}

ipv6filter_cmd () {
	if [ $IPV6_KRNL -lt 1 ]; then
		return 0
	fi

	if [ "$KERN_VERSION" != "$TARGET_KERNEL1"  \
		-a "$KERN_VERSION" != "$TARGET_KERNEL2" \
		-a "$KERN_VERSION" != "$TARGET_KERNEL3" ] ; then
		echo
		echo "IPv6 filters: kernel not version ${TARGET_KERNEL1}.x, ${TARGET_KERNEL2}.x, or ${TARGET_KERNEL3}.x."
		if [ "$IPV6_FWDING_KERNEL" = "FILTER_ON" ]; then
			# Keep the output pretty..
			echo
		fi
		ipv6filter_kernfwd off
		echo
		return 1
	fi
	if ! [ -x $IP6TBL ] ; then
		echo
		echo "IPv6 filters: $IP6TBL not found."
		echo
		return 1
	fi
	case $1 in
	load|reload|restart|reset)
		ipv6filter_iptbl_cfg $IP6TBL_FILE
    		;;
	usebackup)
		local BKUP_NUM=1
    		[ -n "$2" ] && BKUP_NUM="$2"
		ipv6filter_iptbl_cfg "${IP6TBL_FILE}.${BKUP_NUM}"
		;;
	save)
		ipv6filter_iptbl_save
    		;;
	clear|flush)
		ipv6filter_kernfwd off
 		vb echo -n "Flushing IPv6 filters..."
 		ipv6filter_clear
    		vb echo "done."
    		;;
	exec)
		shift
		ipv6filter_exec $*
		;;
	forward|fwd)
		ipv6filter_kernfwd on yes
		;;
	noforward|nofwd)
		ipv6filter_kernfwd off yes
		;;
	
	*)
		echo "Usage: `basename $0` ip6filter load|clear|flush|fwd|nofwd|reload|save"
		echo "                               usebackup [backup-number]"
		echo "       `basename $0` ip6filter exec $IPF6_FNS"
		echo "                              [chain p1 p2 ...]"
		exit 1
		;;
	esac
}


##############################################################################
# Start and stop
##############################################################################

start () {

	start_auto_ipkrnlswch
	ipv4filter_cmd load
	
	if [ $IPV6_KRNL -ge 1 ]; then
		ipv6filter_cmd load
	fi
	
}	#END start ()

stop () {

	vb echo -n "Disabling IPv4 packet forwarding..."
	echo "0" >$IPFWD_V4PROC \
	    && vb echo "done."
	vb echo -n "Flushing IPv4 filters..."
	ipv4filter_clear && vb echo "done."
	
	if [ $IPV6_KRNL -ge 1 ]; then
		vb echo -n "Disabling IPv6 packet forwarding..."
		echo "0" >$IPFWD_V6PROC \
	    		&& vb echo "done."
		vb echo -n "Flushing IPv6 filters..."
		ipv6filter_clear && vb echo "done."
	fi

}	#END stop ()

#############################################################################
# Main - Down to business
#############################################################################


# Handle symlinked ifup and ifdown commands

if [ "`basename $0`" = "ifup" -o "`basename $0`" = "ifdown" ]; then 
	ifupdown $*
fi

case "$1" in
	start)	start	;;
	stop)	stop	;; 
	reload) start reload ;;
	restart|force-reload)
		$0 stop
		sleep 1
		$0 start
		;;

	ipfilter)
		shift
		if ! ipv4filter_cmd $*; then
		    exit 1
		fi
		;;

	*)
		if [ $IPV6_KRNL -ge 1 -a "$1" = "ip6filter" ]; then
			shift
			if ! ipv6filter_cmd $*; then
		    	exit 1
			fi
			exit 0
		fi
		echo "Usage: `basename $0` start|stop|reload|restart" 
		echo "Usage: `basename $0` ipfilter load|clear|fairq|flush|fwd|nofwd|reload|save"
		echo "                              usebackup [backup-number]"
		echo "       `basename $0` ipfilter exec $IPF4_FNS"
		echo "                              [chain p1 p2 ...]"
		if [ $IPV6_KRNL -ge 1 ]; then 
			echo "Usage: `basename $0` ip6filter load|clear|fairq|flush|fwd|nofwd|reload|save"
			echo "                              usebackup [backup-number]"
			echo "       `basename $0` ip6filter exec $IPF6_FNS"
			echo "                              [chain p1 p2 ...]"
		fi
		exit 1 
        ;;
esac

exit 0