2 * Copyright (C)2003,2004 USAGI/WIDE Project
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
11 * 16 Dec 2003: Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
12 * - ICMPv6 tracking support. Derived from the original ip_conntrack code
13 * net/ipv4/netfilter/ip_conntrack_proto_icmp.c which had the following
14 * copyright information:
15 * (C) 1999-2001 Paul `Rusty' Russell
16 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
19 #include <linux/types.h>
20 #include <linux/sched.h>
21 #include <linux/timer.h>
22 #include <linux/module.h>
23 #include <linux/netfilter.h>
24 #include <linux/in6.h>
25 #include <linux/icmpv6.h>
26 #include <linux/ipv6.h>
28 #include <net/ip6_checksum.h>
29 #include <linux/seq_file.h>
30 #include <linux/netfilter_ipv6.h>
31 #include <net/netfilter/nf_conntrack_tuple.h>
32 #include <net/netfilter/nf_conntrack_protocol.h>
33 #include <net/netfilter/nf_conntrack_core.h>
34 #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
36 unsigned long nf_ct_icmpv6_timeout __read_mostly
= 30*HZ
;
41 #define DEBUGP(format, args...)
44 static int icmpv6_pkt_to_tuple(const struct sk_buff
*skb
,
46 struct nf_conntrack_tuple
*tuple
)
48 struct icmp6hdr _hdr
, *hp
;
50 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
53 tuple
->dst
.u
.icmp
.type
= hp
->icmp6_type
;
54 tuple
->src
.u
.icmp
.id
= hp
->icmp6_identifier
;
55 tuple
->dst
.u
.icmp
.code
= hp
->icmp6_code
;
60 /* Add 1; spaces filled with 0. */
61 static u_int8_t invmap
[] = {
62 [ICMPV6_ECHO_REQUEST
- 128] = ICMPV6_ECHO_REPLY
+ 1,
63 [ICMPV6_ECHO_REPLY
- 128] = ICMPV6_ECHO_REQUEST
+ 1,
64 [ICMPV6_NI_QUERY
- 128] = ICMPV6_NI_QUERY
+ 1,
65 [ICMPV6_NI_REPLY
- 128] = ICMPV6_NI_REPLY
+1
68 static int icmpv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
69 const struct nf_conntrack_tuple
*orig
)
71 int type
= orig
->dst
.u
.icmp
.type
- 128;
72 if (type
< 0 || type
>= sizeof(invmap
) || !invmap
[type
])
75 tuple
->src
.u
.icmp
.id
= orig
->src
.u
.icmp
.id
;
76 tuple
->dst
.u
.icmp
.type
= invmap
[type
] - 1;
77 tuple
->dst
.u
.icmp
.code
= orig
->dst
.u
.icmp
.code
;
81 /* Print out the per-protocol part of the tuple. */
82 static int icmpv6_print_tuple(struct seq_file
*s
,
83 const struct nf_conntrack_tuple
*tuple
)
85 return seq_printf(s
, "type=%u code=%u id=%u ",
86 tuple
->dst
.u
.icmp
.type
,
87 tuple
->dst
.u
.icmp
.code
,
88 ntohs(tuple
->src
.u
.icmp
.id
));
91 /* Print out the private part of the conntrack. */
92 static int icmpv6_print_conntrack(struct seq_file
*s
,
93 const struct nf_conn
*conntrack
)
98 /* Returns verdict for packet, or -1 for invalid. */
99 static int icmpv6_packet(struct nf_conn
*ct
,
100 const struct sk_buff
*skb
,
101 unsigned int dataoff
,
102 enum ip_conntrack_info ctinfo
,
104 unsigned int hooknum
)
106 /* Try to delete connection immediately after all replies:
107 won't actually vanish as we still have skb, and del_timer
108 means this will only run once even if count hits zero twice
109 (theoretically possible with SMP) */
110 if (CTINFO2DIR(ctinfo
) == IP_CT_DIR_REPLY
) {
111 if (atomic_dec_and_test(&ct
->proto
.icmp
.count
)
112 && del_timer(&ct
->timeout
))
113 ct
->timeout
.function((unsigned long)ct
);
115 atomic_inc(&ct
->proto
.icmp
.count
);
116 nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE
, skb
);
117 nf_ct_refresh_acct(ct
, ctinfo
, skb
, nf_ct_icmpv6_timeout
);
123 /* Called when a new connection for this protocol found. */
124 static int icmpv6_new(struct nf_conn
*conntrack
,
125 const struct sk_buff
*skb
,
126 unsigned int dataoff
)
128 static u_int8_t valid_new
[] = {
129 [ICMPV6_ECHO_REQUEST
- 128] = 1,
130 [ICMPV6_NI_QUERY
- 128] = 1
132 int type
= conntrack
->tuplehash
[0].tuple
.dst
.u
.icmp
.type
- 128;
134 if (type
< 0 || type
>= sizeof(valid_new
) || !valid_new
[type
]) {
135 /* Can't create a new ICMPv6 `conn' with this. */
136 DEBUGP("icmpv6: can't create new conn with type %u\n",
138 NF_CT_DUMP_TUPLE(&conntrack
->tuplehash
[0].tuple
);
141 atomic_set(&conntrack
->proto
.icmp
.count
, 0);
146 nf_ct_ipv6_skip_exthdr(struct sk_buff
*skb
, int start
, u8
*nexthdrp
, int len
);
147 extern struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6
;
149 icmpv6_error_message(struct sk_buff
*skb
,
150 unsigned int icmp6off
,
151 enum ip_conntrack_info
*ctinfo
,
152 unsigned int hooknum
)
154 struct nf_conntrack_tuple intuple
, origtuple
;
155 struct nf_conntrack_tuple_hash
*h
;
156 struct icmp6hdr _hdr
, *hp
;
157 unsigned int inip6off
;
158 struct nf_conntrack_protocol
*inproto
;
160 unsigned int inprotoff
;
162 NF_CT_ASSERT(skb
->nfct
== NULL
);
164 hp
= skb_header_pointer(skb
, icmp6off
, sizeof(_hdr
), &_hdr
);
166 DEBUGP("icmpv6_error: Can't get ICMPv6 hdr.\n");
170 inip6off
= icmp6off
+ sizeof(_hdr
);
171 if (skb_copy_bits(skb
, inip6off
+offsetof(struct ipv6hdr
, nexthdr
),
172 &inprotonum
, sizeof(inprotonum
)) != 0) {
173 DEBUGP("icmpv6_error: Can't get nexthdr in inner IPv6 header.\n");
176 inprotoff
= nf_ct_ipv6_skip_exthdr(skb
,
177 inip6off
+ sizeof(struct ipv6hdr
),
180 - sizeof(struct ipv6hdr
));
182 if ((inprotoff
< 0) || (inprotoff
> skb
->len
) ||
183 (inprotonum
== NEXTHDR_FRAGMENT
)) {
184 DEBUGP("icmpv6_error: Can't get protocol header in ICMPv6 payload.\n");
188 inproto
= __nf_ct_proto_find(PF_INET6
, inprotonum
);
190 /* Are they talking about one of our connections? */
191 if (!nf_ct_get_tuple(skb
, inip6off
, inprotoff
, PF_INET6
, inprotonum
,
192 &origtuple
, &nf_conntrack_l3proto_ipv6
, inproto
)) {
193 DEBUGP("icmpv6_error: Can't get tuple\n");
197 /* Ordinarily, we'd expect the inverted tupleproto, but it's
198 been preserved inside the ICMP. */
199 if (!nf_ct_invert_tuple(&intuple
, &origtuple
,
200 &nf_conntrack_l3proto_ipv6
, inproto
)) {
201 DEBUGP("icmpv6_error: Can't invert tuple\n");
205 *ctinfo
= IP_CT_RELATED
;
207 h
= nf_conntrack_find_get(&intuple
, NULL
);
209 DEBUGP("icmpv6_error: no match\n");
212 if (NF_CT_DIRECTION(h
) == IP_CT_DIR_REPLY
)
213 *ctinfo
+= IP_CT_IS_REPLY
;
216 /* Update skb to refer to this connection */
217 skb
->nfct
= &nf_ct_tuplehash_to_ctrack(h
)->ct_general
;
218 skb
->nfctinfo
= *ctinfo
;
223 icmpv6_error(struct sk_buff
*skb
, unsigned int dataoff
,
224 enum ip_conntrack_info
*ctinfo
, int pf
, unsigned int hooknum
)
226 struct icmp6hdr _ih
, *icmp6h
;
228 icmp6h
= skb_header_pointer(skb
, dataoff
, sizeof(_ih
), &_ih
);
229 if (icmp6h
== NULL
) {
230 if (LOG_INVALID(IPPROTO_ICMPV6
))
231 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
232 "nf_ct_icmpv6: short packet ");
236 if (nf_conntrack_checksum
&& hooknum
== NF_IP6_PRE_ROUTING
&&
237 nf_ip6_checksum(skb
, hooknum
, dataoff
, IPPROTO_ICMPV6
)) {
238 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
239 "nf_ct_icmpv6: ICMPv6 checksum failed\n");
243 /* is not error message ? */
244 if (icmp6h
->icmp6_type
>= 128)
247 return icmpv6_error_message(skb
, dataoff
, ctinfo
, hooknum
);
250 #if defined(CONFIG_NF_CT_NETLINK) || \
251 defined(CONFIG_NF_CT_NETLINK_MODULE)
253 #include <linux/netfilter/nfnetlink.h>
254 #include <linux/netfilter/nfnetlink_conntrack.h>
255 static int icmpv6_tuple_to_nfattr(struct sk_buff
*skb
,
256 const struct nf_conntrack_tuple
*t
)
258 NFA_PUT(skb
, CTA_PROTO_ICMPV6_ID
, sizeof(u_int16_t
),
260 NFA_PUT(skb
, CTA_PROTO_ICMPV6_TYPE
, sizeof(u_int8_t
),
261 &t
->dst
.u
.icmp
.type
);
262 NFA_PUT(skb
, CTA_PROTO_ICMPV6_CODE
, sizeof(u_int8_t
),
263 &t
->dst
.u
.icmp
.code
);
271 static const size_t cta_min_proto
[CTA_PROTO_MAX
] = {
272 [CTA_PROTO_ICMPV6_TYPE
-1] = sizeof(u_int8_t
),
273 [CTA_PROTO_ICMPV6_CODE
-1] = sizeof(u_int8_t
),
274 [CTA_PROTO_ICMPV6_ID
-1] = sizeof(u_int16_t
)
277 static int icmpv6_nfattr_to_tuple(struct nfattr
*tb
[],
278 struct nf_conntrack_tuple
*tuple
)
280 if (!tb
[CTA_PROTO_ICMPV6_TYPE
-1]
281 || !tb
[CTA_PROTO_ICMPV6_CODE
-1]
282 || !tb
[CTA_PROTO_ICMPV6_ID
-1])
285 if (nfattr_bad_size(tb
, CTA_PROTO_MAX
, cta_min_proto
))
288 tuple
->dst
.u
.icmp
.type
=
289 *(u_int8_t
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_TYPE
-1]);
290 tuple
->dst
.u
.icmp
.code
=
291 *(u_int8_t
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_CODE
-1]);
292 tuple
->src
.u
.icmp
.id
=
293 *(u_int16_t
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_ID
-1]);
295 if (tuple
->dst
.u
.icmp
.type
< 128
296 || tuple
->dst
.u
.icmp
.type
- 128 >= sizeof(invmap
)
297 || !invmap
[tuple
->dst
.u
.icmp
.type
- 128])
304 struct nf_conntrack_protocol nf_conntrack_protocol_icmpv6
=
307 .proto
= IPPROTO_ICMPV6
,
309 .pkt_to_tuple
= icmpv6_pkt_to_tuple
,
310 .invert_tuple
= icmpv6_invert_tuple
,
311 .print_tuple
= icmpv6_print_tuple
,
312 .print_conntrack
= icmpv6_print_conntrack
,
313 .packet
= icmpv6_packet
,
315 .error
= icmpv6_error
,
316 #if defined(CONFIG_NF_CT_NETLINK) || \
317 defined(CONFIG_NF_CT_NETLINK_MODULE)
318 .tuple_to_nfattr
= icmpv6_tuple_to_nfattr
,
319 .nfattr_to_tuple
= icmpv6_nfattr_to_tuple
,
323 EXPORT_SYMBOL(nf_conntrack_protocol_icmpv6
);