firewall: various enhancements
[openwrt.git] / package / network / config / firewall / files / lib / fw.sh
1 # Copyright (C) 2009-2010 OpenWrt.org
2 # Copyright (C) 2009 Malte S. Stretz
3
4 export FW_4_ERROR=0
5 export FW_6_ERROR=0
6 export FW_i_ERROR=0
7 export FW_e_ERROR=0
8 export FW_a_ERROR=0
9
10 #TODO: remove this
11 [ "${-#*x}" == "$-" ] && {
12         fw() {
13                 fw__exec "$@"
14         }
15 } || {
16         fw() {
17                 local os=$-
18                 set +x
19                 fw__exec "$@"
20                 local rc=$?
21                 set -$os
22                 return $rc
23         }
24 }
25
26 fw__exec() { # <action> <family> <table> <chain> <target> <position> { <rules> }
27         local cmd fam tab chn tgt pos
28         local i
29         for i in cmd fam tab chn tgt pos; do
30                 if [ "$1" -a "$1" != '{' ]; then
31                         eval "$i='$1'"
32                         shift
33                 else
34                         eval "$i=-"
35                 fi
36         done
37
38         fw__rc() {
39                 export FW_${fam#G}_ERROR=$1
40                 return $1
41         }
42
43         fw__dualip() {
44                 fw $cmd 4 $tab $chn $tgt $pos "$@"
45                 fw $cmd 6 $tab $chn $tgt $pos "$@"
46                 fw__rc $((FW_4_ERROR | FW_6_ERROR))
47         }
48
49         fw__autoip() {
50                 local ip4 ip6
51                 shift
52                 while [ "$1" != '}' ]; do
53                         case "$1" in
54                                 *:*) ip6=1 ;;
55                                 *.*.*.*) ip4=1 ;;
56                         esac
57                         shift
58                 done
59                 shift
60                 if [ "${ip4:-4}" == "${ip6:-6}" ]; then
61                         echo "fw: can't mix ip4 and ip6" >&2
62                         return 1
63                 fi
64                 local ver=${ip4:+4}${ip6:+6}
65                 fam=i
66                 fw $cmd ${ver:-i} $tab $chn $tgt $pos "$@"
67                 fw__rc $?
68         }
69
70         fw__has() {
71                 local tab=${1:-$tab}
72                 if [ $tab == '-' ]; then
73                         type $app > /dev/null 2> /dev/null
74                         fw__rc $(($? & 1))
75                         return
76                 fi
77                 [ "$app" != ip6tables ] || [ "$tab" != nat ]
78                 fw__rc $?
79         }
80
81         fw__err() {
82                 local err
83                 eval "err=\$FW_${fam}_ERROR"
84                 fw__rc $err
85         }
86
87         local app=
88         local pol=
89         case "$fam" in
90                 *4) [ $FW_DISABLE_IPV4 == 0 ] && app=iptables  || return ;;
91                 *6) [ $FW_DISABLE_IPV6 == 0 ] && app=ip6tables || return ;;
92                 i) fw__dualip "$@"; return ;;
93                 I) fw__autoip "$@"; return ;;
94                 e) app=ebtables ;;
95                 a) app=arptables ;;
96                 -) fw $cmd i $tab $chn $tgt $pos "$@"; return ;;
97                 *) return 254 ;;
98         esac
99         case "$tab" in
100                 f) tab=filter ;;
101                 m) tab=mangle ;;
102                 n) tab=nat ;;
103                 r) tab=raw ;;
104                 -) tab=filter ;;
105         esac
106         case "$cmd:$chn:$tgt:$pos" in
107                 add:*:-:*) cmd=new-chain ;;
108                 add:*:*:-) cmd=append ;;
109                 add:*:*:$) cmd=append ;;
110                 add:*:*:*) cmd=insert ;;
111                 del:-:*:*) cmd=delete-chain; fw flush $fam $tab ;;
112                 del:*:-:*) cmd=delete-chain; fw flush $fam $tab $chn ;;
113                 del:*:*:*) cmd=delete ;;
114                 flush:*) ;;
115                 policy:*) pol=$tgt; tgt=- ;;
116                 has:*) fw__has; return ;;
117                 err:*) fw__err; return ;;
118                 list:*) cmd="numeric --verbose --$cmd" ;;
119                 *) return 254 ;;
120         esac
121         case "$chn" in
122                 -) chn= ;;
123         esac
124         case "$tgt" in
125                 -) tgt= ;;
126         esac
127
128         local rule_offset
129         case "$pos" in
130                 ^) pos=1 ;;
131                 $) pos= ;;
132                 -) pos= ;;
133                 +) eval "rule_offset=\${FW__RULE_OFS_${app}_${tab}_${chn}:-1}" ;;
134         esac
135
136         if ! fw__has - family || ! fw__has $tab ; then
137                 export FW_${fam}_ERROR=0
138                 return 0
139         fi
140
141         case "$fam" in
142                 G*) shift; while [ $# -gt 0 ] && [ "$1" != "{" ]; do shift; done ;;
143         esac
144
145         if [ $# -gt 0 ]; then
146                 shift
147                 if [ $cmd == delete ]; then
148                         pos=
149                 fi
150         fi
151
152         local cmdline="$app --table ${tab} --${cmd} ${chn} ${pol} ${rule_offset:-${pos}} ${tgt:+--jump "$tgt"}"
153         while [ $# -gt 1 ]; do
154                 # special parameter handling
155                 case "$1:$2" in
156                         -p:icmp*|-p:1|-p:58|--protocol:icmp*|--protocol:1|--protocol:58)
157                                 [ "$app" = ip6tables ] && \
158                                         cmdline="$cmdline -p icmpv6" || \
159                                         cmdline="$cmdline -p icmp"
160                                 shift
161                         ;;
162                         --icmp-type:*|--icmpv6-type:*)
163                                 local icmp_type
164                                 if [ "$app" = ip6tables ] && fw_check_icmptype6 icmp_type "$2"; then
165                                         cmdline="$cmdline $icmp_type"
166                                 elif [ "$app" = iptables ] && fw_check_icmptype4 icmp_type "$2"; then
167                                         cmdline="$cmdline $icmp_type"
168                                 else
169                                         local fam=IPv4; [ "$app" = ip6tables ] && fam=IPv6
170                                         fw_log info "ICMP type '$2' is not valid for $fam address family, skipping rule"
171                                         return 1
172                                 fi
173                                 shift
174                         ;;
175                         *) cmdline="$cmdline $1" ;;
176                 esac
177                 shift
178         done
179
180         [ -n "$FW_TRACE" ] && echo $cmdline >&2
181
182         $cmdline
183
184         local rv=$?
185         [ $rv -eq 0 ] && [ -n "$rule_offset" ] && \
186                 export -- "FW__RULE_OFS_${app}_${tab}_${chn}=$(($rule_offset + 1))"
187         fw__rc $rv
188 }
189
190 fw_get_port_range() {
191         local _var=$1
192         local _ports=$2
193         local _delim=${3:-:}
194         if [ "$4" ]; then
195                 fw_get_port_range $_var "${_ports}-${4}" $_delim
196                 return
197         fi
198
199         local _first=${_ports%-*}
200         local _last=${_ports#*-}
201         if [ "${_first#!}" != "${_last#!}" ]; then
202                 export -- "$_var=$_first$_delim${_last#!}"
203         else
204                 export -- "$_var=$_first"
205         fi
206 }
207
208 fw_get_family_mode() {
209         local _var="$1"
210         local _hint="$2"
211         local _zone="$3"
212         local _mode="$4"
213
214         local _ipv4 _ipv6
215         [ "$_zone" != "*" ] && {
216                 [ -n "$FW_ZONES4$FW_ZONES6" ] && {
217                         list_contains FW_ZONES4 "$_zone" && _ipv4=1 || _ipv4=0
218                         list_contains FW_ZONES6 "$_zone" && _ipv6=1 || _ipv6=0
219                 } || {
220                         _ipv4=$(uci_get_state firewall core "${_zone}_ipv4" 0)
221                         _ipv6=$(uci_get_state firewall core "${_zone}_ipv6" 0)
222                 }
223         } || {
224                 _ipv4=1
225                 _ipv6=1
226         }
227
228         case "$_hint:$_ipv4:$_ipv6" in
229                 *4:1:*|*:1:0) export -n -- "$_var=G4" ;;
230                 *6:*:1|*:0:1) export -n -- "$_var=G6" ;;
231                 *) export -n -- "$_var=$_mode" ;;
232         esac
233 }
234
235 fw_get_negation() {
236         local _var="$1"
237         local _flag="$2"
238         local _value="$3"
239
240         [ "${_value#!}" != "$_value" ] && \
241                 export -n -- "$_var=! $_flag ${_value#!}" || \
242                 export -n -- "$_var=${_value:+$_flag $_value}"
243 }
244
245 fw_get_subnet4() {
246         local _var="$1"
247         local _flag="$2"
248         local _name="$3"
249
250         local _ipaddr="$(uci_get_state network "${_name#!}" ipaddr)"
251         local _netmask="$(uci_get_state network "${_name#!}" netmask)"
252
253         case "$_ipaddr" in
254                 *.*.*.*)
255                         [ "${_name#!}" != "$_name" ] && \
256                                 export -n -- "$_var=! $_flag $_ipaddr/${_netmask:-255.255.255.255}" || \
257                                 export -n -- "$_var=$_flag $_ipaddr/${_netmask:-255.255.255.255}"
258                         return 0
259                 ;;
260         esac
261
262         export -n -- "$_var="
263         return 1
264 }
265
266 fw_check_icmptype4() {
267         local _var="$1"
268         local _type="$2"
269         case "$_type" in
270                 ![0-9]*) export -n -- "$_var=! --icmp-type ${_type#!}"; return 0 ;;
271                 [0-9]*)  export -n -- "$_var=--icmp-type $_type";       return 0 ;;
272         esac
273
274         [ -z "$FW_ICMP4_TYPES" ] && \
275                 export FW_ICMP4_TYPES=$(
276                         iptables -p icmp -h 2>/dev/null | \
277                         sed -n -e '/^Valid ICMP Types:/ {
278                                 n; :r; s/[()]/ /g; s/[[:space:]]\+/\n/g; p; n; b r
279                         }' | sort -u
280                 )
281
282         local _check
283         for _check in $FW_ICMP4_TYPES; do
284                 if [ "$_check" = "${_type#!}" ]; then
285                         [ "${_type#!}" != "$_type" ] && \
286                                 export -n -- "$_var=! --icmp-type ${_type#!}" || \
287                                 export -n -- "$_var=--icmp-type $_type"
288                         return 0
289                 fi
290         done
291
292         export -n -- "$_var="
293         return 1
294 }
295
296 fw_check_icmptype6() {
297         local _var="$1"
298         local _type="$2"
299         case "$_type" in
300                 ![0-9]*) export -n -- "$_var=! --icmpv6-type ${_type#!}"; return 0 ;;
301                 [0-9]*)  export -n -- "$_var=--icmpv6-type $_type";       return 0 ;;
302         esac
303
304         [ -z "$FW_ICMP6_TYPES" ] && \
305                 export FW_ICMP6_TYPES=$(
306                         ip6tables -p icmpv6 -h 2>/dev/null | \
307                         sed -n -e '/^Valid ICMPv6 Types:/ {
308                                 n; :r; s/[()]/ /g; s/[[:space:]]\+/\n/g; p; n; b r
309                         }' | sort -u
310                 )
311
312         local _check
313         for _check in $FW_ICMP6_TYPES; do
314                 if [ "$_check" = "${_type#!}" ]; then
315                         [ "${_type#!}" != "$_type" ] && \
316                                 export -n -- "$_var=! --icmpv6-type ${_type#!}" || \
317                                 export -n -- "$_var=--icmpv6-type $_type"
318                         return 0
319                 fi
320         done
321
322         export -n -- "$_var="
323         return 1
324 }