647bcd6a547c3bded9a972f0d475b70f7aceb0bd
[librecmc/librecmc.git] / package / 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                 local mod
78                 eval "mod=\$FW_${fam#G}_${tab}"
79                 if [ "$mod" ]; then
80                         fw__rc $mod
81                         return
82                 fi
83                 case "$fam" in
84                         *4) mod=iptable_${tab} ;;
85                         *6) mod=ip6table_${tab} ;;
86                         *) mod=. ;;
87                 esac
88                 grep -q "^${mod} " /proc/modules
89                 mod=$?
90                 export FW_${fam}_${tab}=$mod
91                 fw__rc $mod
92         }
93
94         fw__err() {
95                 local err
96                 eval "err=\$FW_${fam}_ERROR"
97                 fw__rc $err
98         }
99
100         local app=
101         local pol=
102         case "$fam" in
103                 *4) [ $FW_DISABLE_IPV4 == 0 ] && app=iptables  || return ;;
104                 *6) [ $FW_DISABLE_IPV6 == 0 ] && app=ip6tables || return ;;
105                 i) fw__dualip "$@"; return ;;
106                 I) fw__autoip "$@"; return ;;
107                 e) app=ebtables ;;
108                 a) app=arptables ;;
109                 -) fw $cmd i $tab $chn $tgt $pos "$@"; return ;;
110                 *) return 254 ;;
111         esac
112         case "$tab" in
113                 f) tab=filter ;;
114                 m) tab=mangle ;;
115                 n) tab=nat ;;
116                 r) tab=raw ;;
117                 -) tab=filter ;;
118         esac
119         case "$cmd:$chn:$tgt:$pos" in
120                 add:*:-:*) cmd=new-chain ;;
121                 add:*:*:-) cmd=append ;;
122                 add:*:*:$) cmd=append ;;
123                 add:*:*:*) cmd=insert ;;
124                 del:-:*:*) cmd=delete-chain; fw flush $fam $tab ;;
125                 del:*:-:*) cmd=delete-chain; fw flush $fam $tab $chn ;;
126                 del:*:*:*) cmd=delete ;;
127                 flush:*) ;;
128                 policy:*) pol=$tgt; tgt=- ;;
129                 has:*) fw__has; return ;;
130                 err:*) fw__err; return ;;
131                 list:*) cmd="numeric --verbose --$cmd" ;;
132                 *) return 254 ;;
133         esac
134         case "$chn" in
135                 -) chn= ;;
136         esac
137         case "$tgt" in
138                 -) tgt= ;;
139         esac
140
141         local rule_offset
142         case "$pos" in
143                 ^) pos=1 ;;
144                 $) pos= ;;
145                 -) pos= ;;
146                 +) eval "rule_offset=\${FW__RULE_OFS_${app}_${tab}_${chn}:-1}" ;;
147         esac
148
149         if ! fw__has - family || ! fw__has $tab ; then
150                 export FW_${fam}_ERROR=0
151                 return 0
152         fi
153
154         case "$fam" in
155                 G*) shift; while [ $# -gt 0 ] && [ "$1" != "{" ]; do shift; done ;;
156         esac
157
158         if [ $# -gt 0 ]; then
159                 shift
160                 if [ $cmd == delete ]; then
161                         pos=
162                 fi
163         fi
164
165         local cmdline="$app --table ${tab} --${cmd} ${chn} ${pol} ${rule_offset:-${pos}} ${tgt:+--jump "$tgt"}"
166         while [ $# -gt 1 ]; do
167                 # special parameter handling
168                 case "$1:$2" in
169                         -p:icmp*|--protocol:icmp*)
170                                 [ "$app" = ip6tables ] && \
171                                         cmdline="$cmdline -p icmpv6" || \
172                                         cmdline="$cmdline -p icmp"
173                                 shift
174                         ;;
175                         --icmp-type:*|--icmpv6-type:*)
176                                 local icmp_type
177                                 if [ "$app" = ip6tables ] && fw_check_icmptype6 icmp_type "$2"; then
178                                         cmdline="$cmdline $icmp_type"
179                                 elif [ "$app" = iptables ] && fw_check_icmptype4 icmp_type "$2"; then
180                                         cmdline="$cmdline $icmp_type"
181                                 else
182                                         local fam=IPv4; [ "$app" = ip6tables ] && fam=IPv6
183                                         fw_log info "ICMP type '$2' is not valid for $fam address family, skipping rule"
184                                         return 1
185                                 fi
186                                 shift   
187                         ;;
188                         *) cmdline="$cmdline $1" ;;
189                 esac
190                 shift
191         done
192
193         [ -n "$FW_TRACE" ] && echo $cmdline >&2
194
195         $cmdline
196
197         local rv=$?
198         [ $rv -eq 0 ] && [ -n "$rule_offset" ] && \
199                 export -- "FW__RULE_OFS_${app}_${tab}_${chn}=$(($rule_offset + 1))"
200         fw__rc $rv
201 }
202
203 fw_get_port_range() {
204         local _var=$1
205         local _ports=$2
206         local _delim=${3:-:}
207         if [ "$4" ]; then
208                 fw_get_port_range $_var "${_ports}-${4}" $_delim
209                 return
210         fi
211
212         local _first=${_ports%-*}
213         local _last=${_ports#*-}
214         if [ "${_first#!}" != "${_last#!}" ]; then
215                 export -- "$_var=$_first$_delim${_last#!}"
216         else
217                 export -- "$_var=$_first"
218         fi
219 }
220
221 fw_get_family_mode() {
222         local _var="$1"
223         local _hint="$2"
224         local _zone="$3"
225         local _mode="$4"
226
227         local _ipv4 _ipv6
228         [ -n "$FW_ZONES4$FW_ZONES6" ] && {
229                 list_contains FW_ZONES4 $_zone && _ipv4=1 || _ipv4=0
230                 list_contains FW_ZONES6 $_zone && _ipv6=1 || _ipv6=0
231         } || {
232                 _ipv4=$(uci_get_state firewall core ${_zone}_ipv4 0)
233                 _ipv6=$(uci_get_state firewall core ${_zone}_ipv6 0)
234         }
235
236         case "$_hint:$_ipv4:$_ipv6" in
237                 *4:1:*|*:1:0) export -n -- "$_var=G4" ;;
238                 *6:*:1|*:0:1) export -n -- "$_var=G6" ;;
239                 *) export -n -- "$_var=$_mode" ;;
240         esac
241 }
242
243 fw_get_negation() {
244         local _var="$1"
245         local _flag="$2"
246         local _value="$3"
247
248         [ "${_value#!}" != "$_value" ] && \
249                 export -n -- "$_var=! $_flag ${_value#!}" || \
250                 export -n -- "$_var=${_value:+$_flag $_value}"
251 }
252
253 fw_get_subnet4() {
254         local _var="$1"
255         local _flag="$2"
256         local _name="$3"
257
258         local _ipaddr="$(uci_get_state network "${_name#!}" ipaddr)"
259         local _netmask="$(uci_get_state network "${_name#!}" netmask)"
260
261         case "$_ipaddr" in
262                 *.*.*.*)
263                         [ "${_name#!}" != "$_name" ] && \
264                                 export -n -- "$_var=! $_flag $_ipaddr/${_netmask:-255.255.255.255}" || \
265                                 export -n -- "$_var=$_flag $_ipaddr/${_netmask:-255.255.255.255}"
266                 ;;
267                 *) export -n -- "$_var=" ;;
268         esac
269 }
270
271 fw_check_icmptype4() {
272         local _var="$1"
273         local _type="$2"
274         case "$_type" in
275                 ![0-9]*) export -n -- "$_var=! --icmp-type ${_type#!}"; return 0 ;;
276                 [0-9]*)  export -n -- "$_var=--icmp-type $_type";       return 0 ;;
277         esac
278
279         [ -z "$FW_ICMP4_TYPES" ] && \
280                 export FW_ICMP4_TYPES=$(
281                         iptables -p icmp -h 2>/dev/null | \
282                         sed -n -e '/^Valid ICMP Types:/ {
283                                 n; :r;
284                                 /router-advertisement/d;
285                                 /router-solicitation/d;
286                                 s/[()]/ /g; s/[[:space:]]\+/\n/g; p; n; b r
287                         }' | sort -u
288                 )
289
290         local _check
291         for _check in $FW_ICMP4_TYPES; do
292                 if [ "$_check" = "${_type#!}" ]; then
293                         [ "${_type#!}" != "$_type" ] && \
294                                 export -n -- "$_var=! --icmp-type ${_type#!}" || \
295                                 export -n -- "$_var=--icmp-type $_type"
296                         return 0
297                 fi
298         done
299
300         export -n -- "$_var="
301         return 1
302 }
303
304 fw_check_icmptype6() {
305         local _var="$1"
306         local _type="$2"
307         case "$_type" in
308                 ![0-9]*) export -n -- "$_var=! --icmpv6-type ${_type#!}"; return 0 ;;
309                 [0-9]*)  export -n -- "$_var=--icmpv6-type $_type";       return 0 ;;
310         esac
311
312         [ -z "$FW_ICMP6_TYPES" ] && \
313                 export FW_ICMP6_TYPES=$(
314                         ip6tables -p icmpv6 -h 2>/dev/null | \
315                         sed -n -e '/^Valid ICMPv6 Types:/ {
316                                 n; :r; s/[()]/ /g; s/[[:space:]]\+/\n/g; p; n; b r
317                         }' | sort -u
318                 )
319
320         local _check
321         for _check in $FW_ICMP6_TYPES; do
322                 if [ "$_check" = "${_type#!}" ]; then
323                         [ "${_type#!}" != "$_type" ] && \
324                                 export -n -- "$_var=! --icmpv6-type ${_type#!}" || \
325                                 export -n -- "$_var=--icmpv6-type $_type"
326                         return 0
327                 fi
328         done
329
330         export -n -- "$_var="
331         return 1
332 }