blob: 738d3f3b1d5d1b46fa21df5f6b6267abf3ca4083 (
plain)
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
|
#!/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
NAME=iptables-rules
DESC="iptables filter rules"
iptables_bin="/usr/sbin/iptables"
ip6tables_bin="/usr/sbin/ip6tables"
die()
{
echo "$*"
exit 1
}
iptables()
{
$iptables_bin "$@" || die "FAILED: $iptables_bin $@"
}
ip6tables()
{
$ip6tables_bin "$@" || die "FAILED: $ip6tables_bin $@"
}
clear_ip4tables()
{
# clear and delete all chains
iptables -F
iptables -X
iptables -Z
# delete `nat' and `mangle' chains
iptables -t mangle -F
iptables -t nat -F
}
clear_ip6tables()
{
# clear and delete all chains
ip6tables -F INPUT
ip6tables -F OUTPUT
ip6tables -F FORWARD
ip6tables -F
ip6tables -X
ip6tables -Z
# delete `mangle' chain
ip6tables -t mangle -F
}
clear_all_ipt_rules()
{
clear_ip4tables
clear_ip6tables
}
setup_ip4tables()
{
# default policy
iptables -P INPUT DROP
iptables -P FORWARD DROP
iptables -P OUTPUT DROP
# loopback
iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
# UDP
iptables -A INPUT -p udp -j ACCEPT # Accept everything
# Established connections
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
iptables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
if true; then
# forwarding and masquerading
echo 1 >/proc/sys/net/ipv4/ip_forward
for inif in eth+ usb+; do
for outif in wlan+ ppp+ tun+; do
iptables -t nat -A POSTROUTING -o $outif -j MASQUERADE
iptables -A FORWARD -i $inif -o $outif -j ACCEPT
iptables -A FORWARD -i $outif -o $inif -j ACCEPT
done
done
fi
# Output
iptables -A OUTPUT -j ACCEPT
# ICMP
iptables -A OUTPUT -p icmp --icmp-type echo-request -j ACCEPT
iptables -A OUTPUT -p icmp --icmp-type echo-reply -j ACCEPT
iptables -A INPUT -p icmp --icmp-type echo-reply -j ACCEPT
iptables -A INPUT -p icmp --icmp-type echo-request -j ACCEPT
iptables -A OUTPUT -p icmp --icmp-type destination-unreachable -j ACCEPT
iptables -A INPUT -p icmp --icmp-type destination-unreachable -j ACCEPT
iptables -A INPUT -p icmp --icmp-type source-quench -j ACCEPT
iptables -A INPUT -p icmp --icmp-type time-exceeded -j ACCEPT
iptables -A INPUT -p icmp --icmp-type parameter-problem -j ACCEPT
# logging
# iptables -A INPUT -j LOG --log-level info --log-prefix "reject_ipv4_input:"
# iptables -A OUTPUT -j LOG --log-level info --log-prefix "reject_ipv4_output:"
# iptables -A FORWARD -j LOG --log-level info --log-prefix "reject_ipv4_forward:"
# REJECT the rest
iptables -A INPUT -j REJECT
iptables -A OUTPUT -j REJECT
iptables -A FORWARD -j REJECT
}
setup_ip6tables()
{
# default policy
ip6tables -P INPUT DROP
ip6tables -P FORWARD DROP
ip6tables -P OUTPUT DROP
# Disable processing of any RH0 packet
# Which could allow a ping-pong of packets
ip6tables -A INPUT -m rt --rt-type 0 -j DROP
ip6tables -A OUTPUT -m rt --rt-type 0 -j DROP
ip6tables -A FORWARD -m rt --rt-type 0 -j DROP
# loopback
ip6tables -A INPUT -i lo -j ACCEPT
ip6tables -A OUTPUT -o lo -j ACCEPT
# Allow Link-Local addresses
# ip6tables -A INPUT -s fe80::/10 -j ACCEPT
# ip6tables -A OUTPUT -s fe80::/10 -j ACCEPT
# Allow multicast
# ip6tables -A INPUT -s ff00::/8 -j ACCEPT
# ip6tables -A OUTPUT -s ff00::/8 -j ACCEPT
# Established connections
ip6tables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
ip6tables -A OUTPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
# Output
ip6tables -A OUTPUT -j ACCEPT
# ICMP
ip6tables -A INPUT -p icmpv6 -j ACCEPT
ip6tables -A OUTPUT -p icmpv6 -j ACCEPT
ip6tables -A FORWARD -p icmpv6 -j ACCEPT
# logging
# ip6tables -A INPUT -j LOG --log-level info --log-prefix "reject_ipv6_input:"
# ip6tables -A OUTPUT -j LOG --log-level info --log-prefix "reject_ipv6_output:"
# ip6tables -A FORWARD -j LOG --log-level info --log-prefix "reject_ipv6_forward:"
# REJECT the rest
ip6tables -A INPUT -j REJECT
ip6tables -A OUTPUT -j REJECT
ip6tables -A FORWARD -j REJECT
}
setup_iptables()
{
clear_all_ipt_rules
setup_ip4tables
setup_ip6tables
}
reset_iptables()
{
clear_all_ipt_rules
iptables -P INPUT ACCEPT
iptables -P FORWARD ACCEPT
iptables -P OUTPUT ACCEPT
ip6tables -P INPUT ACCEPT
ip6tables -P FORWARD ACCEPT
ip6tables -P OUTPUT ACCEPT
}
sanity_checks()
{
[ $(id -u) -eq 0 ] || die "Permission denied"
[ -x "$iptables_bin" ] || die "Can not execute iptables binary \"$iptables_bin\""
[ -x "$ip6tables_bin" ] || die "Can not execute ip6tables binary \"$ip6tables_bin\""
}
sanity_checks
case "$1" in
start|restart|reload)
echo "Starting $DESC: $NAME"
setup_iptables
;;
stop)
echo "Stopping $DESC: $NAME"
reset_iptables
;;
*)
echo "Usage: $0 {start|stop|restart|reload}"
exit 1
;;
esac
exit 0
|
