firewall: Remove even more redundant rules.
[people/teissler/ipfire-2.x.git] / src / initscripts / init.d / firewall
1 #!/bin/sh
2
3 . /etc/sysconfig/rc
4 . ${rc_functions}
5
6 eval $(/usr/local/bin/readhash /var/ipfire/ppp/settings)
7 eval $(/usr/local/bin/readhash /var/ipfire/ethernet/settings)
8 eval $(/usr/local/bin/readhash /var/ipfire/optionsfw/settings)
9 IFACE=`/bin/cat /var/ipfire/red/iface 2> /dev/null | /usr/bin/tr -d '\012'`
10
11 if [ -f /var/ipfire/red/device ]; then
12 DEVICE=`/bin/cat /var/ipfire/red/device 2> /dev/null | /usr/bin/tr -d '\012'`
13 fi
14
15 function iptables() {
16 /sbin/iptables --wait "$@"
17 }
18
19 iptables_init() {
20 # Flush all rules and delete all custom chains
21 iptables -F
22 iptables -t nat -F
23 iptables -t mangle -F
24 iptables -X
25 iptables -t nat -X
26 iptables -t mangle -X
27
28 # Set up policies
29 iptables -P INPUT DROP
30 iptables -P FORWARD DROP
31 iptables -P OUTPUT ACCEPT
32
33 # Empty LOG_DROP and LOG_REJECT chains
34 iptables -N LOG_DROP
35 iptables -A LOG_DROP -m limit --limit 10/minute -j LOG
36 iptables -A LOG_DROP -j DROP
37 iptables -N LOG_REJECT
38 iptables -A LOG_REJECT -m limit --limit 10/minute -j LOG
39 iptables -A LOG_REJECT -j REJECT
40
41 # This chain will log, then DROPs packets with certain bad combinations
42 # of flags might indicate a port-scan attempt (xmas, null, etc)
43 iptables -N PSCAN
44 if [ "$DROPPORTSCAN" == "on" ]; then
45 iptables -A PSCAN -p tcp -m limit --limit 10/minute -j LOG --log-prefix "DROP_TCP Scan " -m comment --comment "DROP_TCP PScan"
46 iptables -A PSCAN -p udp -m limit --limit 10/minute -j LOG --log-prefix "DROP_UDP Scan " -m comment --comment "DROP_UDP PScan"
47 iptables -A PSCAN -p icmp -m limit --limit 10/minute -j LOG --log-prefix "DROP_ICMP Scan " -m comment --comment "DROP_ICMP PScan"
48 iptables -A PSCAN -f -m limit --limit 10/minute -j LOG --log-prefix "DROP_FRAG Scan " -m comment --comment "DROP_FRAG PScan"
49 fi
50 iptables -A PSCAN -j DROP -m comment --comment "DROP_PScan"
51
52 # New tcp packets without SYN set - could well be an obscure type of port scan
53 # that's not covered above, may just be a broken windows machine
54 iptables -N NEWNOTSYN
55 if [ "$DROPNEWNOTSYN" == "on" ]; then
56 iptables -A NEWNOTSYN -m limit --limit 10/minute -j LOG --log-prefix "DROP_NEWNOTSYN "
57 fi
58 iptables -A NEWNOTSYN -j DROP -m comment --comment "DROP_NEWNOTSYN"
59
60 # Chain to contain all the rules relating to bad TCP flags
61 iptables -N BADTCP
62
63 # Don't check loopback
64 iptables -A BADTCP -i lo -j RETURN
65
66 # Disallow packets frequently used by port-scanners
67 # nmap xmas
68 iptables -A BADTCP -p tcp --tcp-flags ALL FIN,URG,PSH -j PSCAN
69 # Null
70 iptables -A BADTCP -p tcp --tcp-flags ALL NONE -j PSCAN
71 # FIN
72 iptables -A BADTCP -p tcp --tcp-flags ALL FIN -j PSCAN
73 # SYN/RST (also catches xmas variants that set SYN+RST+...)
74 iptables -A BADTCP -p tcp --tcp-flags SYN,RST SYN,RST -j PSCAN
75 # SYN/FIN (QueSO or nmap OS probe)
76 iptables -A BADTCP -p tcp --tcp-flags SYN,FIN SYN,FIN -j PSCAN
77 # NEW TCP without SYN
78 iptables -A BADTCP -p tcp ! --syn -m conntrack --ctstate NEW -j NEWNOTSYN
79
80 iptables -A INPUT -p tcp -j BADTCP
81 iptables -A FORWARD -p tcp -j BADTCP
82
83 # Connection tracking chain
84 iptables -N CONNTRACK
85 iptables -A CONNTRACK -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT
86
87 # Fix for braindead ISP's
88 iptables -A FORWARD -p tcp --tcp-flags SYN,RST SYN -j TCPMSS --clamp-mss-to-pmtu
89
90 # CUSTOM chains, can be used by the users themselves
91 iptables -N CUSTOMINPUT
92 iptables -A INPUT -j CUSTOMINPUT
93 iptables -N CUSTOMFORWARD
94 iptables -A FORWARD -j CUSTOMFORWARD
95 iptables -N CUSTOMOUTPUT
96 iptables -A OUTPUT -j CUSTOMOUTPUT
97 iptables -t nat -N CUSTOMPREROUTING
98 iptables -t nat -A PREROUTING -j CUSTOMPREROUTING
99 iptables -t nat -N CUSTOMPOSTROUTING
100 iptables -t nat -A POSTROUTING -j CUSTOMPOSTROUTING
101
102 # Guardian (IPS) chains
103 iptables -N GUARDIAN
104 iptables -A INPUT -j GUARDIAN
105 iptables -A FORWARD -j GUARDIAN
106
107 # Block OpenVPN transfer networks
108 iptables -N OVPNBLOCK
109 for i in INPUT FORWARD; do
110 iptables -A ${i} -j OVPNBLOCK
111 done
112
113 # OpenVPN transfer network translation
114 iptables -t nat -N OVPNNAT
115 iptables -t nat -A POSTROUTING -j OVPNNAT
116
117 # IPTV chains for IGMPPROXY
118 iptables -N IPTVINPUT
119 iptables -A INPUT -j IPTVINPUT
120 iptables -N IPTVFORWARD
121 iptables -A FORWARD -j IPTVFORWARD
122
123 # filtering from GUI
124 iptables -N GUIINPUT
125 iptables -A INPUT -j GUIINPUT
126 iptables -A GUIINPUT -p icmp --icmp-type 8 -j ACCEPT
127
128 # Accept everything on loopback
129 iptables -N LOOPBACK
130 iptables -A LOOPBACK -i lo -j ACCEPT
131 iptables -A LOOPBACK -o lo -j ACCEPT
132
133 # Filter all packets with loopback addresses on non-loopback interfaces.
134 iptables -A LOOPBACK -s 127.0.0.0/8 -j DROP
135 iptables -A LOOPBACK -d 127.0.0.0/8 -j DROP
136
137 for i in INPUT FORWARD OUTPUT; do
138 iptables -A ${i} -j LOOPBACK
139 done
140
141 # Accept everything connected
142 for i in INPUT FORWARD OUTPUT; do
143 iptables -A ${i} -j CONNTRACK
144 done
145
146 # trafic from ipsecX/TUN/TAP interfaces, before "-i GREEN_DEV" accept everything
147 iptables -N IPSECINPUT
148 iptables -N IPSECFORWARD
149 iptables -N IPSECOUTPUT
150 iptables -A INPUT -j IPSECINPUT
151 iptables -A FORWARD -j IPSECFORWARD
152 iptables -A OUTPUT -j IPSECOUTPUT
153 iptables -t nat -N IPSECNAT
154 iptables -t nat -A POSTROUTING -j IPSECNAT
155
156 # localhost and ethernet.
157 iptables -A INPUT -i $GREEN_DEV -m conntrack --ctstate NEW -j ACCEPT ! -p icmp
158
159 # allow DHCP on BLUE to be turned on/off
160 iptables -N DHCPBLUEINPUT
161 iptables -A INPUT -j DHCPBLUEINPUT
162
163 # WIRELESS chains
164 iptables -N WIRELESSINPUT
165 iptables -A INPUT -m conntrack --ctstate NEW -j WIRELESSINPUT
166 iptables -N WIRELESSFORWARD
167 iptables -A FORWARD -m conntrack --ctstate NEW -j WIRELESSFORWARD
168
169 # OpenVPN
170 iptables -N OVPNINPUT
171 iptables -A INPUT -j OVPNINPUT
172
173 # TOR
174 iptables -N TOR_INPUT
175 iptables -A INPUT -j TOR_INPUT
176
177 # Jump into the actual firewall ruleset.
178 iptables -N INPUTFW
179 iptables -A INPUT -j INPUTFW
180
181 iptables -N OUTGOINGFW
182 iptables -A OUTPUT -j OUTGOINGFW
183
184 iptables -N FORWARDFW
185 iptables -A FORWARD -j FORWARDFW
186
187 # SNAT rules
188 iptables -t nat -N NAT_SOURCE
189 iptables -t nat -A POSTROUTING -j NAT_SOURCE
190
191 # RED chain, used for the red interface
192 iptables -N REDINPUT
193 iptables -A INPUT -j REDINPUT
194 iptables -N REDFORWARD
195 iptables -A FORWARD -j REDFORWARD
196 iptables -t nat -N REDNAT
197 iptables -t nat -A POSTROUTING -j REDNAT
198
199 iptables_red
200
201 # Custom prerouting chains (for transparent proxy)
202 iptables -t nat -N SQUID
203 iptables -t nat -A PREROUTING -j SQUID
204
205 # DNAT rules
206 iptables -t nat -N NAT_DESTINATION
207 iptables -t nat -A PREROUTING -j NAT_DESTINATION
208
209 # upnp chain for our upnp daemon
210 iptables -t nat -N UPNPFW
211 iptables -t nat -A PREROUTING -j UPNPFW
212 iptables -N UPNPFW
213 iptables -A FORWARD -m conntrack --ctstate NEW -j UPNPFW
214
215 # Apply OpenVPN firewall rules
216 /usr/local/bin/openvpnctrl --firewall-rules
217
218 # run wirelessctrl
219 /usr/local/bin/wirelessctrl
220
221 # POLICY CHAIN
222 iptables -N POLICYIN
223 iptables -A INPUT -j POLICYIN
224 iptables -N POLICYFWD
225 iptables -A FORWARD -j POLICYFWD
226 iptables -N POLICYOUT
227 iptables -A OUTPUT -j POLICYOUT
228
229 /usr/sbin/firewall-policy
230
231 # read new firewall
232 /usr/local/bin/firewallctrl
233 }
234
235 iptables_red() {
236 iptables -F REDINPUT
237 iptables -F REDFORWARD
238 iptables -t nat -F REDNAT
239
240 # PPPoE / PPTP Device
241 if [ "$IFACE" != "" ]; then
242 # PPPoE / PPTP
243 if [ "$DEVICE" != "" ]; then
244 iptables -A REDINPUT -i $DEVICE -j ACCEPT
245 fi
246 if [ "$RED_TYPE" == "PPTP" -o "$RED_TYPE" == "PPPOE" ]; then
247 if [ "$RED_DEV" != "" ]; then
248 iptables -A REDINPUT -i $RED_DEV -j ACCEPT
249 fi
250 fi
251 fi
252
253 # PPTP over DHCP
254 if [ "$DEVICE" != "" -a "$TYPE" == "PPTP" -a "$METHOD" == "DHCP" ]; then
255 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
256 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $DEVICE -j ACCEPT
257 fi
258
259 # Orange pinholes
260 if [ "$ORANGE_DEV" != "" ]; then
261 # This rule enables a host on ORANGE network to connect to the outside
262 # (only if we have a red connection)
263 if [ "$IFACE" != "" ]; then
264 iptables -A REDFORWARD -i $ORANGE_DEV -o $IFACE -j ACCEPT
265 fi
266 fi
267
268 if [ "$IFACE" != "" -a -f /var/ipfire/red/active ]; then
269 # DHCP
270 if [ "$RED_DEV" != "" -a "$RED_TYPE" == "DHCP" ]; then
271 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
272 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
273 fi
274 if [ "$METHOD" == "DHCP" -a "$PROTOCOL" == "RFC1483" ]; then
275 iptables -A REDINPUT -p tcp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
276 iptables -A REDINPUT -p udp --source-port 67 --destination-port 68 -i $IFACE -j ACCEPT
277 fi
278
279 # Outgoing masquerading (don't masqerade IPSEC (mark 50))
280 iptables -t nat -A REDNAT -m mark --mark 50 -o $IFACE -j RETURN
281 iptables -t nat -A REDNAT -o $IFACE -j MASQUERADE
282
283 fi
284 }
285
286 # See how we were called.
287 case "$1" in
288 start)
289 boot_mesg "Loading firewall modules into the kernel"
290 modprobe iptable_nat || failed=1
291 for i in $(find /lib/modules/$(uname -r) -name nf_conntrack*); do
292 modprobe $(basename $i | cut -d. -f1) || failed=1
293 done
294 for i in $(find /lib/modules/$(uname -r) -name nf_nat*); do
295 modprobe $(basename $i | cut -d. -f1) || failed=1
296 done
297 (exit ${failed})
298 evaluate_retval
299
300 if [ -e /var/ipfire/main/disable_nf_sip ]; then
301 rmmod nf_nat_sip
302 rmmod nf_conntrack_sip
303 rmmod nf_nat_h323
304 rmmod nf_conntrack_h323
305 fi
306
307 boot_mesg "Setting up firewall"
308 iptables_init
309 evaluate_retval
310
311 # run local firewall configuration, if present
312 if [ -x /etc/sysconfig/firewall.local ]; then
313 /etc/sysconfig/firewall.local start
314 fi
315 ;;
316 reload)
317 boot_mesg "Reloading firewall"
318 iptables_red
319 evaluate_retval
320
321 # run local firewall configuration, if present
322 if [ -x /etc/sysconfig/firewall.local ]; then
323 /etc/sysconfig/firewall.local reload
324 fi
325 ;;
326 restart)
327 # run local firewall configuration, if present
328 if [ -x /etc/sysconfig/firewall.local ]; then
329 /etc/sysconfig/firewall.local stop
330 fi
331 $0 start
332 ;;
333 *)
334 echo "Usage: $0 {start|reload|restart}"
335 exit 1
336 ;;
337 esac
338
339 exit 0