firewall: flush conntrack table after changing interface rules
[openwrt.git] / package / network / config / firewall / files / lib / core_interface.sh
1 # Copyright (C) 2009-2012 OpenWrt.org
2
3 fw__uci_state_add() {
4         local var="$1"
5         local item="$2"
6
7         local val="$(uci_get_state firewall core $var)"
8         local e1; for e1 in $item; do
9                 local e2; for e2 in $val; do
10                         [ "$e1" = "$e2" ] && e1=""
11                 done
12                 val="${val:+$val${e1:+ }}$e1"
13         done
14
15         uci_toggle_state firewall core $var "$val"
16 }
17
18 fw__uci_state_del() {
19         local var="$1"
20         local item="$2"
21
22         local rest=""
23         local val="$(uci_get_state firewall core $var)"
24         local e1; for e1 in $val; do
25                 local e2; for e2 in $item; do
26                         [ "$e1" = "$e2" ] && e1=""
27                 done
28                 rest="${rest:+$rest${e1:+ }}$e1"
29         done
30
31         uci_toggle_state firewall core $var "$rest"
32 }
33
34 fw_configure_interface() {
35         local iface=$1
36         local action=$2
37         local ifname=$3
38         local aliasnet=$4
39
40         [ "$action" == "add" ] && {
41                 local status=$(uci_get_state network "$iface" up 0)
42                 [ "$status" == 1 ] || [ -n "$aliasnet" ] || return 0
43         }
44
45         [ -n "$ifname" ] || {
46                 ifname=$(uci_get_state network "$iface" ifname)
47                 ifname="${ifname%%:*}"
48                 [ -z "$ifname" ] && return 0
49         }
50
51         [ "$ifname" == "lo" ] && return 0
52
53         fw_callback pre interface
54
55         fw__do_rules() {
56                 local action=$1
57                 local zone=$2
58                 local chain=zone_${zone}
59                 local ifname=$3
60                 local subnet=$4
61
62                 local inet onet mode
63                 fw_get_family_mode mode x $zone i
64
65                 case "$mode/$subnet" in
66                         # Zone supports v6 only or dual, need v6
67                         G6/*:*|i/*:*)
68                                 inet="-s $subnet -d ::/0"
69                                 onet="-s ::/0 -d $subnet"
70                                 mode=6
71                         ;;
72
73                         # Zone supports v4 only or dual, need v4
74                         G4/*.*.*.*|i/*.*.*.*)
75                                 inet="-s $subnet -d 0.0.0.0/0"
76                                 onet="-s 0.0.0.0/0 -d $subnet"
77                                 mode=4
78                         ;;
79
80                         # Need v6 while zone is v4
81                         */*:*) fw_log info "zone $zone does not support IPv6 address family, skipping"; return ;;
82
83                         # Need v4 while zone is v6
84                         */*.*) fw_log info "zone $zone does not support IPv4 address family, skipping"; return ;;
85
86                         # Strip prefix
87                         *) mode="${mode#G}" ;;
88                 esac
89
90                 lock /var/run/firewall-interface.lock
91
92                 fw $action $mode f ${chain}_ACCEPT ACCEPT $ { -o "$ifname" $onet }
93                 fw $action $mode f ${chain}_ACCEPT ACCEPT $ { -i "$ifname" $inet }
94                 fw $action $mode f ${chain}_DROP   DROP   $ { -o "$ifname" $onet }
95                 fw $action $mode f ${chain}_DROP   DROP   $ { -i "$ifname" $inet }
96                 fw $action $mode f ${chain}_REJECT reject $ { -o "$ifname" $onet }
97                 fw $action $mode f ${chain}_REJECT reject $ { -i "$ifname" $inet }
98
99                 [ "$(uci_get_state firewall core "${zone}_tcpmss")" == 1 ] && \
100                         fw $action $mode m ${chain}_MSSFIX TCPMSS $ \
101                                 { -o "$ifname" -p tcp --tcp-flags SYN,RST SYN --clamp-mss-to-pmtu $onet }
102
103                 fw $action $mode f input   ${chain}         $ { -i "$ifname" $inet }
104                 fw $action $mode f forward ${chain}_forward $ { -i "$ifname" $inet }
105                 fw $action $mode n PREROUTING ${chain}_prerouting $ { -i "$ifname" $inet }
106                 fw $action $mode r PREROUTING ${chain}_notrack    $ { -i "$ifname" $inet }
107                 fw $action $mode n POSTROUTING ${chain}_nat       $ { -o "$ifname" $onet }
108
109                 # Flush conntrack table
110                 echo f >/proc/net/nf_conntrack 2>/dev/null
111
112                 lock -u /var/run/firewall-interface.lock
113         }
114
115         local old_zones old_ifname old_subnets
116         config_get old_zones core "${iface}_zone"
117         [ -n "$old_zones" ] && {
118                 config_get old_ifname core "${iface}_ifname"
119                 config_get old_subnets core "${iface}_subnets"
120
121                 local z
122                 for z in $old_zones; do
123                         local n
124                         for n in ${old_subnets:-""}; do
125                                 fw_log info "removing $iface ($old_ifname${n:+ alias $n}) from zone $z"
126                                 fw__do_rules del $z $old_ifname $n
127                         done
128
129                         [ -n "$old_subnets" ] || {
130                                 fw__uci_state_del "${z}_networks" "$iface"
131                                 env -i ACTION=remove ZONE="$z" INTERFACE="$iface" DEVICE="$ifname" /sbin/hotplug-call firewall
132                         }
133                 done
134
135                 local old_aliases
136                 config_get old_aliases core "${iface}_aliases"
137
138                 local a
139                 for a in $old_aliases; do
140                         fw_configure_interface "$a" del "$old_ifname"
141                 done
142
143                 uci_revert_state firewall core "${iface}_zone"
144                 uci_revert_state firewall core "${iface}_ifname"
145                 uci_revert_state firewall core "${iface}_subnets"
146                 uci_revert_state firewall core "${iface}_aliases"
147         }
148
149         [ "$action" == del ] && return
150
151         [ -z "$aliasnet" ] && {
152                 local aliases
153                 config_get aliases "$iface" aliases
154
155                 local a
156                 for a in $aliases; do
157                         local ipaddr netmask ip6addr
158                         config_get ipaddr "$a" ipaddr
159                         config_get netmask "$a" netmask
160                         config_get ip6addr "$a" ip6addr
161
162                         [ -n "$ipaddr" ] && fw_configure_interface "$a" add "" "$ipaddr${netmask:+/$netmask}"
163                         [ -n "$ip6addr" ] && fw_configure_interface "$a" add "" "$ip6addr"
164                 done
165
166                 fw_sysctl_interface $ifname
167                 fw_callback post interface
168
169                 uci_toggle_state firewall core "${iface}_aliases" "$aliases"
170         } || {
171                 local subnets=
172                 config_get subnets core "${iface}_subnets"
173                 append subnets "$aliasnet"
174
175                 config_set core "${iface}_subnets" "$subnets"
176                 uci_toggle_state firewall core "${iface}_subnets" "$subnets"
177         }
178
179         local new_zones=
180         load_zone() {
181                 fw_config_get_zone "$1"
182                 list_contains zone_network "$iface" || return
183
184                 fw_log info "adding $iface ($ifname${aliasnet:+ alias $aliasnet}) to zone $zone_name"
185                 fw__do_rules add ${zone_name} "$ifname" "$aliasnet"
186                 append new_zones $zone_name
187
188                 [ -n "$aliasnet" ] || {
189                         fw__uci_state_add "${zone_name}_networks" "${zone_network}"
190                         env -i ACTION=add ZONE="$zone_name" INTERFACE="$iface" DEVICE="$ifname" /sbin/hotplug-call firewall
191                 }
192         }
193         config_foreach load_zone zone
194
195         uci_toggle_state firewall core "${iface}_zone" "$new_zones"
196         uci_toggle_state firewall core "${iface}_ifname" "$ifname"
197 }
198
199 fw_sysctl_interface() {
200         local ifname=$1
201         {
202                 sysctl -w net.ipv4.conf.${ifname}.accept_redirects=$FW_ACCEPT_REDIRECTS
203                 sysctl -w net.ipv6.conf.${ifname}.accept_redirects=$FW_ACCEPT_REDIRECTS
204                 sysctl -w net.ipv4.conf.${ifname}.accept_source_route=$FW_ACCEPT_SRC_ROUTE
205                 sysctl -w net.ipv6.conf.${ifname}.accept_source_route=$FW_ACCEPT_SRC_ROUTE
206         } >/dev/null 2>/dev/null
207 }
208