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. */
4 /* (C) 1999-2001 Paul `Rusty' Russell
5 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
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.
12 #include <linux/module.h>
13 #include <linux/types.h>
14 #include <linux/udp.h>
15 #include <linux/skbuff.h>
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>
23 MODULE_LICENSE("GPL");
24 MODULE_AUTHOR("Netfilter Core Team <coreteam@netfilter.org>");
25 MODULE_DESCRIPTION("Xtables: multiple port matching for TCP, UDP, UDP-Lite, SCTP and DCCP");
26 MODULE_ALIAS("ipt_multiport");
27 MODULE_ALIAS("ip6t_multiport");
30 #define duprintf(format, args...) printk(format , ## args)
32 #define duprintf(format, args...)
35 /* Returns 1 if the port is matched by the test, 0 otherwise. */
37 ports_match_v0(const u_int16_t
*portlist
, enum xt_multiport_flags flags
,
38 u_int8_t count
, u_int16_t src
, u_int16_t dst
)
41 for (i
= 0; i
< count
; i
++) {
42 if (flags
!= XT_MULTIPORT_DESTINATION
&& portlist
[i
] == src
)
45 if (flags
!= XT_MULTIPORT_SOURCE
&& portlist
[i
] == dst
)
52 /* Returns 1 if the port is matched by the test, 0 otherwise. */
54 ports_match_v1(const struct xt_multiport_v1
*minfo
,
55 u_int16_t src
, u_int16_t dst
)
60 for (i
= 0; i
< minfo
->count
; i
++) {
63 if (minfo
->pflags
[i
]) {
64 /* range port matching */
65 e
= minfo
->ports
[++i
];
66 duprintf("src or dst matches with %d-%d?\n", s
, e
);
68 if (minfo
->flags
== XT_MULTIPORT_SOURCE
69 && src
>= s
&& src
<= e
)
70 return true ^ minfo
->invert
;
71 if (minfo
->flags
== XT_MULTIPORT_DESTINATION
72 && dst
>= s
&& dst
<= e
)
73 return true ^ minfo
->invert
;
74 if (minfo
->flags
== XT_MULTIPORT_EITHER
75 && ((dst
>= s
&& dst
<= e
)
76 || (src
>= s
&& src
<= e
)))
77 return true ^ minfo
->invert
;
79 /* exact port matching */
80 duprintf("src or dst matches with %d?\n", s
);
82 if (minfo
->flags
== XT_MULTIPORT_SOURCE
84 return true ^ minfo
->invert
;
85 if (minfo
->flags
== XT_MULTIPORT_DESTINATION
87 return true ^ minfo
->invert
;
88 if (minfo
->flags
== XT_MULTIPORT_EITHER
89 && (src
== s
|| dst
== s
))
90 return true ^ minfo
->invert
;
98 multiport_mt_v0(const struct sk_buff
*skb
, const struct net_device
*in
,
99 const struct net_device
*out
, const struct xt_match
*match
,
100 const void *matchinfo
, int offset
, unsigned int protoff
,
103 __be16 _ports
[2], *pptr
;
104 const struct xt_multiport
*multiinfo
= matchinfo
;
109 pptr
= skb_header_pointer(skb
, protoff
, sizeof(_ports
), _ports
);
111 /* We've been asked to examine this packet, and we
112 * can't. Hence, no choice but to drop.
114 duprintf("xt_multiport: Dropping evil offset=0 tinygram.\n");
119 return ports_match_v0(multiinfo
->ports
, multiinfo
->flags
,
120 multiinfo
->count
, ntohs(pptr
[0]), ntohs(pptr
[1]));
124 multiport_mt(const struct sk_buff
*skb
, const struct net_device
*in
,
125 const struct net_device
*out
, const struct xt_match
*match
,
126 const void *matchinfo
, int offset
, unsigned int protoff
,
129 __be16 _ports
[2], *pptr
;
130 const struct xt_multiport_v1
*multiinfo
= matchinfo
;
135 pptr
= skb_header_pointer(skb
, protoff
, sizeof(_ports
), _ports
);
137 /* We've been asked to examine this packet, and we
138 * can't. Hence, no choice but to drop.
140 duprintf("xt_multiport: Dropping evil offset=0 tinygram.\n");
145 return ports_match_v1(multiinfo
, ntohs(pptr
[0]), ntohs(pptr
[1]));
149 check(u_int16_t proto
,
150 u_int8_t ip_invflags
,
151 u_int8_t match_flags
,
154 /* Must specify supported protocol, no unknown flags or bad count */
155 return (proto
== IPPROTO_TCP
|| proto
== IPPROTO_UDP
156 || proto
== IPPROTO_UDPLITE
157 || proto
== IPPROTO_SCTP
|| proto
== IPPROTO_DCCP
)
158 && !(ip_invflags
& XT_INV_PROTO
)
159 && (match_flags
== XT_MULTIPORT_SOURCE
160 || match_flags
== XT_MULTIPORT_DESTINATION
161 || match_flags
== XT_MULTIPORT_EITHER
)
162 && count
<= XT_MULTI_PORTS
;
165 /* Called when user tries to insert an entry of this type. */
167 multiport_mt_check_v0(const char *tablename
, const void *info
,
168 const struct xt_match
*match
, void *matchinfo
,
169 unsigned int hook_mask
)
171 const struct ipt_ip
*ip
= info
;
172 const struct xt_multiport
*multiinfo
= matchinfo
;
174 return check(ip
->proto
, ip
->invflags
, multiinfo
->flags
,
179 multiport_mt_check(const char *tablename
, const void *info
,
180 const struct xt_match
*match
, void *matchinfo
,
181 unsigned int hook_mask
)
183 const struct ipt_ip
*ip
= info
;
184 const struct xt_multiport_v1
*multiinfo
= matchinfo
;
186 return check(ip
->proto
, ip
->invflags
, multiinfo
->flags
,
191 multiport_mt6_check_v0(const char *tablename
, const void *info
,
192 const struct xt_match
*match
, void *matchinfo
,
193 unsigned int hook_mask
)
195 const struct ip6t_ip6
*ip
= info
;
196 const struct xt_multiport
*multiinfo
= matchinfo
;
198 return check(ip
->proto
, ip
->invflags
, multiinfo
->flags
,
203 multiport_mt6_check(const char *tablename
, const void *info
,
204 const struct xt_match
*match
, void *matchinfo
,
205 unsigned int hook_mask
)
207 const struct ip6t_ip6
*ip
= info
;
208 const struct xt_multiport_v1
*multiinfo
= matchinfo
;
210 return check(ip
->proto
, ip
->invflags
, multiinfo
->flags
,
214 static struct xt_match multiport_mt_reg
[] __read_mostly
= {
219 .checkentry
= multiport_mt_check_v0
,
220 .match
= multiport_mt_v0
,
221 .matchsize
= sizeof(struct xt_multiport
),
228 .checkentry
= multiport_mt_check
,
229 .match
= multiport_mt
,
230 .matchsize
= sizeof(struct xt_multiport_v1
),
237 .checkentry
= multiport_mt6_check_v0
,
238 .match
= multiport_mt_v0
,
239 .matchsize
= sizeof(struct xt_multiport
),
246 .checkentry
= multiport_mt6_check
,
247 .match
= multiport_mt
,
248 .matchsize
= sizeof(struct xt_multiport_v1
),
253 static int __init
multiport_mt_init(void)
255 return xt_register_matches(multiport_mt_reg
,
256 ARRAY_SIZE(multiport_mt_reg
));
259 static void __exit
multiport_mt_exit(void)
261 xt_unregister_matches(multiport_mt_reg
, ARRAY_SIZE(multiport_mt_reg
));
264 module_init(multiport_mt_init
);
265 module_exit(multiport_mt_exit
);