Commit | Line | Data |
---|---|---|
ba4e58ec GR |
1 | /* Kernel module to match one of a list of TCP/UDP(-Lite)/SCTP/DCCP ports: |
2 | ports are in the same place so we can treat them as equal. */ | |
a89ecb6a YK |
3 | |
4 | /* (C) 1999-2001 Paul `Rusty' Russell | |
5 | * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org> | |
6 | * | |
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. | |
10 | */ | |
be91fd5e | 11 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
a89ecb6a YK |
12 | #include <linux/module.h> |
13 | #include <linux/types.h> | |
14 | #include <linux/udp.h> | |
15 | #include <linux/skbuff.h> | |
16 | #include <linux/in.h> | |
17 | ||
18 | #include <linux/netfilter/xt_multiport.h> | |
19 | #include <linux/netfilter/x_tables.h> | |
20 | #include <linux/netfilter_ipv4/ip_tables.h> | |
21 | #include <linux/netfilter_ipv6/ip6_tables.h> | |
22 | ||
23 | MODULE_LICENSE("GPL"); | |
24 | MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>"); | |
2ae15b64 | 25 | MODULE_DESCRIPTION("Xtables: multiple port matching for TCP, UDP, UDP-Lite, SCTP and DCCP"); |
a89ecb6a YK |
26 | MODULE_ALIAS("ipt_multiport"); |
27 | MODULE_ALIAS("ip6t_multiport"); | |
28 | ||
a89ecb6a | 29 | /* Returns 1 if the port is matched by the test, 0 otherwise. */ |
1d93a9cb | 30 | static inline bool |
a89ecb6a YK |
31 | ports_match_v1(const struct xt_multiport_v1 *minfo, |
32 | u_int16_t src, u_int16_t dst) | |
33 | { | |
34 | unsigned int i; | |
35 | u_int16_t s, e; | |
36 | ||
37 | for (i = 0; i < minfo->count; i++) { | |
38 | s = minfo->ports[i]; | |
39 | ||
40 | if (minfo->pflags[i]) { | |
41 | /* range port matching */ | |
42 | e = minfo->ports[++i]; | |
be91fd5e | 43 | pr_debug("src or dst matches with %d-%d?\n", s, e); |
a89ecb6a YK |
44 | |
45 | if (minfo->flags == XT_MULTIPORT_SOURCE | |
46 | && src >= s && src <= e) | |
1d93a9cb | 47 | return true ^ minfo->invert; |
a89ecb6a YK |
48 | if (minfo->flags == XT_MULTIPORT_DESTINATION |
49 | && dst >= s && dst <= e) | |
1d93a9cb | 50 | return true ^ minfo->invert; |
a89ecb6a YK |
51 | if (minfo->flags == XT_MULTIPORT_EITHER |
52 | && ((dst >= s && dst <= e) | |
53 | || (src >= s && src <= e))) | |
1d93a9cb | 54 | return true ^ minfo->invert; |
a89ecb6a YK |
55 | } else { |
56 | /* exact port matching */ | |
be91fd5e | 57 | pr_debug("src or dst matches with %d?\n", s); |
a89ecb6a YK |
58 | |
59 | if (minfo->flags == XT_MULTIPORT_SOURCE | |
60 | && src == s) | |
1d93a9cb | 61 | return true ^ minfo->invert; |
a89ecb6a YK |
62 | if (minfo->flags == XT_MULTIPORT_DESTINATION |
63 | && dst == s) | |
1d93a9cb | 64 | return true ^ minfo->invert; |
a89ecb6a YK |
65 | if (minfo->flags == XT_MULTIPORT_EITHER |
66 | && (src == s || dst == s)) | |
1d93a9cb | 67 | return true ^ minfo->invert; |
a89ecb6a YK |
68 | } |
69 | } | |
70 | ||
601e68e1 | 71 | return minfo->invert; |
a89ecb6a YK |
72 | } |
73 | ||
1d93a9cb | 74 | static bool |
62fc8051 | 75 | multiport_mt(const struct sk_buff *skb, struct xt_action_param *par) |
a89ecb6a | 76 | { |
3cf93c96 JE |
77 | const __be16 *pptr; |
78 | __be16 _ports[2]; | |
f7108a20 | 79 | const struct xt_multiport_v1 *multiinfo = par->matchinfo; |
a89ecb6a | 80 | |
f7108a20 | 81 | if (par->fragoff != 0) |
1d93a9cb | 82 | return false; |
a89ecb6a | 83 | |
f7108a20 | 84 | pptr = skb_header_pointer(skb, par->thoff, sizeof(_ports), _ports); |
a89ecb6a YK |
85 | if (pptr == NULL) { |
86 | /* We've been asked to examine this packet, and we | |
87 | * can't. Hence, no choice but to drop. | |
88 | */ | |
be91fd5e | 89 | pr_debug("Dropping evil offset=0 tinygram.\n"); |
b4ba2611 | 90 | par->hotdrop = true; |
1d93a9cb | 91 | return false; |
a89ecb6a YK |
92 | } |
93 | ||
94 | return ports_match_v1(multiinfo, ntohs(pptr[0]), ntohs(pptr[1])); | |
95 | } | |
96 | ||
ccb79bdc | 97 | static inline bool |
a89ecb6a YK |
98 | check(u_int16_t proto, |
99 | u_int8_t ip_invflags, | |
100 | u_int8_t match_flags, | |
101 | u_int8_t count) | |
102 | { | |
957dc80a PM |
103 | /* Must specify supported protocol, no unknown flags or bad count */ |
104 | return (proto == IPPROTO_TCP || proto == IPPROTO_UDP | |
ba4e58ec | 105 | || proto == IPPROTO_UDPLITE |
957dc80a | 106 | || proto == IPPROTO_SCTP || proto == IPPROTO_DCCP) |
a89ecb6a YK |
107 | && !(ip_invflags & XT_INV_PROTO) |
108 | && (match_flags == XT_MULTIPORT_SOURCE | |
109 | || match_flags == XT_MULTIPORT_DESTINATION | |
110 | || match_flags == XT_MULTIPORT_EITHER) | |
111 | && count <= XT_MULTI_PORTS; | |
112 | } | |
113 | ||
b0f38452 | 114 | static int multiport_mt_check(const struct xt_mtchk_param *par) |
a89ecb6a | 115 | { |
9b4fce7a JE |
116 | const struct ipt_ip *ip = par->entryinfo; |
117 | const struct xt_multiport_v1 *multiinfo = par->matchinfo; | |
a89ecb6a YK |
118 | |
119 | return check(ip->proto, ip->invflags, multiinfo->flags, | |
c29c9492 | 120 | multiinfo->count) ? 0 : -EINVAL; |
a89ecb6a YK |
121 | } |
122 | ||
b0f38452 | 123 | static int multiport_mt6_check(const struct xt_mtchk_param *par) |
a89ecb6a | 124 | { |
9b4fce7a JE |
125 | const struct ip6t_ip6 *ip = par->entryinfo; |
126 | const struct xt_multiport_v1 *multiinfo = par->matchinfo; | |
a89ecb6a YK |
127 | |
128 | return check(ip->proto, ip->invflags, multiinfo->flags, | |
c29c9492 | 129 | multiinfo->count) ? 0 : -EINVAL; |
a89ecb6a YK |
130 | } |
131 | ||
d3c5ee6d | 132 | static struct xt_match multiport_mt_reg[] __read_mostly = { |
4470bbc7 PM |
133 | { |
134 | .name = "multiport", | |
ee999d8b | 135 | .family = NFPROTO_IPV4, |
4470bbc7 | 136 | .revision = 1, |
d3c5ee6d JE |
137 | .checkentry = multiport_mt_check, |
138 | .match = multiport_mt, | |
4470bbc7 PM |
139 | .matchsize = sizeof(struct xt_multiport_v1), |
140 | .me = THIS_MODULE, | |
141 | }, | |
4470bbc7 PM |
142 | { |
143 | .name = "multiport", | |
ee999d8b | 144 | .family = NFPROTO_IPV6, |
4470bbc7 | 145 | .revision = 1, |
d3c5ee6d JE |
146 | .checkentry = multiport_mt6_check, |
147 | .match = multiport_mt, | |
4470bbc7 PM |
148 | .matchsize = sizeof(struct xt_multiport_v1), |
149 | .me = THIS_MODULE, | |
150 | }, | |
a89ecb6a YK |
151 | }; |
152 | ||
d3c5ee6d | 153 | static int __init multiport_mt_init(void) |
a89ecb6a | 154 | { |
d3c5ee6d JE |
155 | return xt_register_matches(multiport_mt_reg, |
156 | ARRAY_SIZE(multiport_mt_reg)); | |
a89ecb6a YK |
157 | } |
158 | ||
d3c5ee6d | 159 | static void __exit multiport_mt_exit(void) |
a89ecb6a | 160 | { |
d3c5ee6d | 161 | xt_unregister_matches(multiport_mt_reg, ARRAY_SIZE(multiport_mt_reg)); |
a89ecb6a YK |
162 | } |
163 | ||
d3c5ee6d JE |
164 | module_init(multiport_mt_init); |
165 | module_exit(multiport_mt_exit); |