2 * iptables module to match inet_addr_type() of an ip.
4 * Copyright (c) 2004 Patrick McHardy <kaber@trash.net>
5 * (C) 2007 Laszlo Attila Toth <panther@balabit.hu>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include <linux/kernel.h>
13 #include <linux/module.h>
14 #include <linux/skbuff.h>
15 #include <linux/netdevice.h>
17 #include <net/route.h>
19 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
21 #include <net/ip6_route.h>
22 #include <net/ip6_fib.h>
25 #include <linux/netfilter/xt_addrtype.h>
26 #include <linux/netfilter/x_tables.h>
28 MODULE_LICENSE("GPL");
29 MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
30 MODULE_DESCRIPTION("Xtables: address type match");
31 MODULE_ALIAS("ipt_addrtype");
32 MODULE_ALIAS("ip6t_addrtype");
34 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
35 static u32
xt_addrtype_rt6_to_type(const struct rt6_info
*rt
)
40 return XT_ADDRTYPE_UNREACHABLE
;
42 if (rt
->rt6i_flags
& RTF_REJECT
)
43 ret
= XT_ADDRTYPE_UNREACHABLE
;
47 if (rt
->rt6i_flags
& RTF_LOCAL
)
48 ret
|= XT_ADDRTYPE_LOCAL
;
49 if (rt
->rt6i_flags
& RTF_ANYCAST
)
50 ret
|= XT_ADDRTYPE_ANYCAST
;
54 static bool match_type6(struct net
*net
, const struct net_device
*dev
,
55 const struct in6_addr
*addr
, u16 mask
)
57 int addr_type
= ipv6_addr_type(addr
);
59 if ((mask
& XT_ADDRTYPE_MULTICAST
) &&
60 !(addr_type
& IPV6_ADDR_MULTICAST
))
62 if ((mask
& XT_ADDRTYPE_UNICAST
) && !(addr_type
& IPV6_ADDR_UNICAST
))
64 if ((mask
& XT_ADDRTYPE_UNSPEC
) && addr_type
!= IPV6_ADDR_ANY
)
67 if ((XT_ADDRTYPE_LOCAL
| XT_ADDRTYPE_ANYCAST
|
68 XT_ADDRTYPE_UNREACHABLE
) & mask
) {
71 int ifindex
= dev
? dev
->ifindex
: 0;
73 rt
= rt6_lookup(net
, addr
, NULL
, ifindex
, !!dev
);
75 type
= xt_addrtype_rt6_to_type(rt
);
77 dst_release(&rt
->dst
);
78 return !!(mask
& type
);
84 addrtype_mt6(struct net
*net
, const struct net_device
*dev
,
85 const struct sk_buff
*skb
, const struct xt_addrtype_info_v1
*info
)
87 const struct ipv6hdr
*iph
= ipv6_hdr(skb
);
91 ret
&= match_type6(net
, dev
, &iph
->saddr
, info
->source
) ^
92 (info
->flags
& XT_ADDRTYPE_INVERT_SOURCE
);
93 if (ret
&& info
->dest
)
94 ret
&= match_type6(net
, dev
, &iph
->daddr
, info
->dest
) ^
95 !!(info
->flags
& XT_ADDRTYPE_INVERT_DEST
);
100 static inline bool match_type(struct net
*net
, const struct net_device
*dev
,
101 __be32 addr
, u_int16_t mask
)
103 return !!(mask
& (1 << inet_dev_addr_type(net
, dev
, addr
)));
107 addrtype_mt_v0(const struct sk_buff
*skb
, struct xt_action_param
*par
)
109 struct net
*net
= dev_net(par
->in
? par
->in
: par
->out
);
110 const struct xt_addrtype_info
*info
= par
->matchinfo
;
111 const struct iphdr
*iph
= ip_hdr(skb
);
115 ret
&= match_type(net
, NULL
, iph
->saddr
, info
->source
) ^
118 ret
&= match_type(net
, NULL
, iph
->daddr
, info
->dest
) ^
125 addrtype_mt_v1(const struct sk_buff
*skb
, struct xt_action_param
*par
)
127 struct net
*net
= dev_net(par
->in
? par
->in
: par
->out
);
128 const struct xt_addrtype_info_v1
*info
= par
->matchinfo
;
129 const struct iphdr
*iph
;
130 const struct net_device
*dev
= NULL
;
133 if (info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_IN
)
135 else if (info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_OUT
)
138 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
139 if (par
->family
== NFPROTO_IPV6
)
140 return addrtype_mt6(net
, dev
, skb
, info
);
144 ret
&= match_type(net
, dev
, iph
->saddr
, info
->source
) ^
145 (info
->flags
& XT_ADDRTYPE_INVERT_SOURCE
);
146 if (ret
&& info
->dest
)
147 ret
&= match_type(net
, dev
, iph
->daddr
, info
->dest
) ^
148 !!(info
->flags
& XT_ADDRTYPE_INVERT_DEST
);
152 static int addrtype_mt_checkentry_v1(const struct xt_mtchk_param
*par
)
154 struct xt_addrtype_info_v1
*info
= par
->matchinfo
;
156 if (info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_IN
&&
157 info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_OUT
) {
158 pr_info("both incoming and outgoing "
159 "interface limitation cannot be selected\n");
163 if (par
->hook_mask
& ((1 << NF_INET_PRE_ROUTING
) |
164 (1 << NF_INET_LOCAL_IN
)) &&
165 info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_OUT
) {
166 pr_info("output interface limitation "
167 "not valid in PREROUTING and INPUT\n");
171 if (par
->hook_mask
& ((1 << NF_INET_POST_ROUTING
) |
172 (1 << NF_INET_LOCAL_OUT
)) &&
173 info
->flags
& XT_ADDRTYPE_LIMIT_IFACE_IN
) {
174 pr_info("input interface limitation "
175 "not valid in POSTROUTING and OUTPUT\n");
179 #if defined(CONFIG_IP6_NF_IPTABLES) || defined(CONFIG_IP6_NF_IPTABLES_MODULE)
180 if (par
->family
== NFPROTO_IPV6
) {
181 if ((info
->source
| info
->dest
) & XT_ADDRTYPE_BLACKHOLE
) {
182 pr_err("ipv6 BLACKHOLE matching not supported\n");
185 if ((info
->source
| info
->dest
) >= XT_ADDRTYPE_PROHIBIT
) {
186 pr_err("ipv6 PROHIBT (THROW, NAT ..) matching not supported\n");
189 if ((info
->source
| info
->dest
) & XT_ADDRTYPE_BROADCAST
) {
190 pr_err("ipv6 does not support BROADCAST matching\n");
198 static struct xt_match addrtype_mt_reg
[] __read_mostly
= {
201 .family
= NFPROTO_IPV4
,
202 .match
= addrtype_mt_v0
,
203 .matchsize
= sizeof(struct xt_addrtype_info
),
208 .family
= NFPROTO_UNSPEC
,
210 .match
= addrtype_mt_v1
,
211 .checkentry
= addrtype_mt_checkentry_v1
,
212 .matchsize
= sizeof(struct xt_addrtype_info_v1
),
217 static int __init
addrtype_mt_init(void)
219 return xt_register_matches(addrtype_mt_reg
,
220 ARRAY_SIZE(addrtype_mt_reg
));
223 static void __exit
addrtype_mt_exit(void)
225 xt_unregister_matches(addrtype_mt_reg
, ARRAY_SIZE(addrtype_mt_reg
));
228 module_init(addrtype_mt_init
);
229 module_exit(addrtype_mt_exit
);