Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * iptables module to match inet_addr_type() of an ip. | |
3 | * | |
4 | * Copyright (c) 2004 Patrick McHardy <kaber@trash.net> | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | */ | |
10 | ||
11 | #include <linux/kernel.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/skbuff.h> | |
14 | #include <linux/netdevice.h> | |
15 | #include <linux/ip.h> | |
16 | #include <net/route.h> | |
17 | ||
18 | #include <linux/netfilter_ipv4/ipt_addrtype.h> | |
19 | #include <linux/netfilter_ipv4/ip_tables.h> | |
20 | ||
21 | MODULE_LICENSE("GPL"); | |
22 | MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); | |
23 | MODULE_DESCRIPTION("iptables addrtype match"); | |
24 | ||
25 | static inline int match_type(u_int32_t addr, u_int16_t mask) | |
26 | { | |
27 | return !!(mask & (1 << inet_addr_type(addr))); | |
28 | } | |
29 | ||
30 | static int match(const struct sk_buff *skb, const struct net_device *in, | |
31 | const struct net_device *out, const void *matchinfo, | |
32 | int offset, int *hotdrop) | |
33 | { | |
34 | const struct ipt_addrtype_info *info = matchinfo; | |
35 | const struct iphdr *iph = skb->nh.iph; | |
36 | int ret = 1; | |
37 | ||
38 | if (info->source) | |
39 | ret &= match_type(iph->saddr, info->source)^info->invert_source; | |
40 | if (info->dest) | |
41 | ret &= match_type(iph->daddr, info->dest)^info->invert_dest; | |
42 | ||
43 | return ret; | |
44 | } | |
45 | ||
46 | static int checkentry(const char *tablename, const struct ipt_ip *ip, | |
47 | void *matchinfo, unsigned int matchsize, | |
48 | unsigned int hook_mask) | |
49 | { | |
50 | if (matchsize != IPT_ALIGN(sizeof(struct ipt_addrtype_info))) { | |
51 | printk(KERN_ERR "ipt_addrtype: invalid size (%u != %Zu)\n.", | |
52 | matchsize, IPT_ALIGN(sizeof(struct ipt_addrtype_info))); | |
53 | return 0; | |
54 | } | |
55 | ||
56 | return 1; | |
57 | } | |
58 | ||
59 | static struct ipt_match addrtype_match = { | |
60 | .name = "addrtype", | |
61 | .match = match, | |
62 | .checkentry = checkentry, | |
63 | .me = THIS_MODULE | |
64 | }; | |
65 | ||
66 | static int __init init(void) | |
67 | { | |
68 | return ipt_register_match(&addrtype_match); | |
69 | } | |
70 | ||
71 | static void __exit fini(void) | |
72 | { | |
73 | ipt_unregister_match(&addrtype_match); | |
74 | } | |
75 | ||
76 | module_init(init); | |
77 | module_exit(fini); |