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>
12 #include <linux/types.h>
13 #include <linux/timer.h>
14 #include <linux/module.h>
15 #include <linux/netfilter.h>
16 #include <linux/in6.h>
17 #include <linux/icmpv6.h>
18 #include <linux/ipv6.h>
20 #include <net/ip6_checksum.h>
21 #include <linux/seq_file.h>
22 #include <linux/netfilter_ipv6.h>
23 #include <net/netfilter/nf_conntrack_tuple.h>
24 #include <net/netfilter/nf_conntrack_l4proto.h>
25 #include <net/netfilter/nf_conntrack_core.h>
26 #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
28 static unsigned long nf_ct_icmpv6_timeout __read_mostly
= 30*HZ
;
33 #define DEBUGP(format, args...)
36 static int icmpv6_pkt_to_tuple(const struct sk_buff
*skb
,
38 struct nf_conntrack_tuple
*tuple
)
40 struct icmp6hdr _hdr
, *hp
;
42 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
45 tuple
->dst
.u
.icmp
.type
= hp
->icmp6_type
;
46 tuple
->src
.u
.icmp
.id
= hp
->icmp6_identifier
;
47 tuple
->dst
.u
.icmp
.code
= hp
->icmp6_code
;
52 /* Add 1; spaces filled with 0. */
53 static u_int8_t invmap
[] = {
54 [ICMPV6_ECHO_REQUEST
- 128] = ICMPV6_ECHO_REPLY
+ 1,
55 [ICMPV6_ECHO_REPLY
- 128] = ICMPV6_ECHO_REQUEST
+ 1,
56 [ICMPV6_NI_QUERY
- 128] = ICMPV6_NI_QUERY
+ 1,
57 [ICMPV6_NI_REPLY
- 128] = ICMPV6_NI_REPLY
+1
60 static int icmpv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
61 const struct nf_conntrack_tuple
*orig
)
63 int type
= orig
->dst
.u
.icmp
.type
- 128;
64 if (type
< 0 || type
>= sizeof(invmap
) || !invmap
[type
])
67 tuple
->src
.u
.icmp
.id
= orig
->src
.u
.icmp
.id
;
68 tuple
->dst
.u
.icmp
.type
= invmap
[type
] - 1;
69 tuple
->dst
.u
.icmp
.code
= orig
->dst
.u
.icmp
.code
;
73 /* Print out the per-protocol part of the tuple. */
74 static int icmpv6_print_tuple(struct seq_file
*s
,
75 const struct nf_conntrack_tuple
*tuple
)
77 return seq_printf(s
, "type=%u code=%u id=%u ",
78 tuple
->dst
.u
.icmp
.type
,
79 tuple
->dst
.u
.icmp
.code
,
80 ntohs(tuple
->src
.u
.icmp
.id
));
83 /* Print out the private part of the conntrack. */
84 static int icmpv6_print_conntrack(struct seq_file
*s
,
85 const struct nf_conn
*conntrack
)
90 /* Returns verdict for packet, or -1 for invalid. */
91 static int icmpv6_packet(struct nf_conn
*ct
,
92 const struct sk_buff
*skb
,
94 enum ip_conntrack_info ctinfo
,
98 /* Try to delete connection immediately after all replies:
99 won't actually vanish as we still have skb, and del_timer
100 means this will only run once even if count hits zero twice
101 (theoretically possible with SMP) */
102 if (CTINFO2DIR(ctinfo
) == IP_CT_DIR_REPLY
) {
103 if (atomic_dec_and_test(&ct
->proto
.icmp
.count
)
104 && del_timer(&ct
->timeout
))
105 ct
->timeout
.function((unsigned long)ct
);
107 atomic_inc(&ct
->proto
.icmp
.count
);
108 nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE
, skb
);
109 nf_ct_refresh_acct(ct
, ctinfo
, skb
, nf_ct_icmpv6_timeout
);
115 /* Called when a new connection for this protocol found. */
116 static int icmpv6_new(struct nf_conn
*conntrack
,
117 const struct sk_buff
*skb
,
118 unsigned int dataoff
)
120 static u_int8_t valid_new
[] = {
121 [ICMPV6_ECHO_REQUEST
- 128] = 1,
122 [ICMPV6_NI_QUERY
- 128] = 1
124 int type
= conntrack
->tuplehash
[0].tuple
.dst
.u
.icmp
.type
- 128;
126 if (type
< 0 || type
>= sizeof(valid_new
) || !valid_new
[type
]) {
127 /* Can't create a new ICMPv6 `conn' with this. */
128 DEBUGP("icmpv6: can't create new conn with type %u\n",
130 NF_CT_DUMP_TUPLE(&conntrack
->tuplehash
[0].tuple
);
133 atomic_set(&conntrack
->proto
.icmp
.count
, 0);
138 icmpv6_error_message(struct sk_buff
*skb
,
139 unsigned int icmp6off
,
140 enum ip_conntrack_info
*ctinfo
,
141 unsigned int hooknum
)
143 struct nf_conntrack_tuple intuple
, origtuple
;
144 struct nf_conntrack_tuple_hash
*h
;
145 struct icmp6hdr _hdr
, *hp
;
146 unsigned int inip6off
;
147 struct nf_conntrack_l4proto
*inproto
;
149 unsigned int inprotoff
;
151 NF_CT_ASSERT(skb
->nfct
== NULL
);
153 hp
= skb_header_pointer(skb
, icmp6off
, sizeof(_hdr
), &_hdr
);
155 DEBUGP("icmpv6_error: Can't get ICMPv6 hdr.\n");
159 inip6off
= icmp6off
+ sizeof(_hdr
);
160 if (skb_copy_bits(skb
, inip6off
+offsetof(struct ipv6hdr
, nexthdr
),
161 &inprotonum
, sizeof(inprotonum
)) != 0) {
162 DEBUGP("icmpv6_error: Can't get nexthdr in inner IPv6 header.\n");
165 inprotoff
= nf_ct_ipv6_skip_exthdr(skb
,
166 inip6off
+ sizeof(struct ipv6hdr
),
169 - sizeof(struct ipv6hdr
));
171 if ((inprotoff
< 0) || (inprotoff
> skb
->len
) ||
172 (inprotonum
== NEXTHDR_FRAGMENT
)) {
173 DEBUGP("icmpv6_error: Can't get protocol header in ICMPv6 payload.\n");
177 /* rcu_read_lock()ed by nf_hook_slow */
178 inproto
= __nf_ct_l4proto_find(PF_INET6
, inprotonum
);
180 /* Are they talking about one of our connections? */
181 if (!nf_ct_get_tuple(skb
, inip6off
, inprotoff
, PF_INET6
, inprotonum
,
182 &origtuple
, &nf_conntrack_l3proto_ipv6
, inproto
)) {
183 DEBUGP("icmpv6_error: Can't get tuple\n");
187 /* Ordinarily, we'd expect the inverted tupleproto, but it's
188 been preserved inside the ICMP. */
189 if (!nf_ct_invert_tuple(&intuple
, &origtuple
,
190 &nf_conntrack_l3proto_ipv6
, inproto
)) {
191 DEBUGP("icmpv6_error: Can't invert tuple\n");
195 *ctinfo
= IP_CT_RELATED
;
197 h
= nf_conntrack_find_get(&intuple
, NULL
);
199 DEBUGP("icmpv6_error: no match\n");
202 if (NF_CT_DIRECTION(h
) == IP_CT_DIR_REPLY
)
203 *ctinfo
+= IP_CT_IS_REPLY
;
206 /* Update skb to refer to this connection */
207 skb
->nfct
= &nf_ct_tuplehash_to_ctrack(h
)->ct_general
;
208 skb
->nfctinfo
= *ctinfo
;
213 icmpv6_error(struct sk_buff
*skb
, unsigned int dataoff
,
214 enum ip_conntrack_info
*ctinfo
, int pf
, unsigned int hooknum
)
216 struct icmp6hdr _ih
, *icmp6h
;
218 icmp6h
= skb_header_pointer(skb
, dataoff
, sizeof(_ih
), &_ih
);
219 if (icmp6h
== NULL
) {
220 if (LOG_INVALID(IPPROTO_ICMPV6
))
221 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
222 "nf_ct_icmpv6: short packet ");
226 if (nf_conntrack_checksum
&& hooknum
== NF_IP6_PRE_ROUTING
&&
227 nf_ip6_checksum(skb
, hooknum
, dataoff
, IPPROTO_ICMPV6
)) {
228 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
229 "nf_ct_icmpv6: ICMPv6 checksum failed\n");
233 /* is not error message ? */
234 if (icmp6h
->icmp6_type
>= 128)
237 return icmpv6_error_message(skb
, dataoff
, ctinfo
, hooknum
);
240 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
242 #include <linux/netfilter/nfnetlink.h>
243 #include <linux/netfilter/nfnetlink_conntrack.h>
244 static int icmpv6_tuple_to_nfattr(struct sk_buff
*skb
,
245 const struct nf_conntrack_tuple
*t
)
247 NFA_PUT(skb
, CTA_PROTO_ICMPV6_ID
, sizeof(u_int16_t
),
249 NFA_PUT(skb
, CTA_PROTO_ICMPV6_TYPE
, sizeof(u_int8_t
),
250 &t
->dst
.u
.icmp
.type
);
251 NFA_PUT(skb
, CTA_PROTO_ICMPV6_CODE
, sizeof(u_int8_t
),
252 &t
->dst
.u
.icmp
.code
);
260 static const size_t cta_min_proto
[CTA_PROTO_MAX
] = {
261 [CTA_PROTO_ICMPV6_TYPE
-1] = sizeof(u_int8_t
),
262 [CTA_PROTO_ICMPV6_CODE
-1] = sizeof(u_int8_t
),
263 [CTA_PROTO_ICMPV6_ID
-1] = sizeof(u_int16_t
)
266 static int icmpv6_nfattr_to_tuple(struct nfattr
*tb
[],
267 struct nf_conntrack_tuple
*tuple
)
269 if (!tb
[CTA_PROTO_ICMPV6_TYPE
-1]
270 || !tb
[CTA_PROTO_ICMPV6_CODE
-1]
271 || !tb
[CTA_PROTO_ICMPV6_ID
-1])
274 if (nfattr_bad_size(tb
, CTA_PROTO_MAX
, cta_min_proto
))
277 tuple
->dst
.u
.icmp
.type
=
278 *(u_int8_t
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_TYPE
-1]);
279 tuple
->dst
.u
.icmp
.code
=
280 *(u_int8_t
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_CODE
-1]);
281 tuple
->src
.u
.icmp
.id
=
282 *(__be16
*)NFA_DATA(tb
[CTA_PROTO_ICMPV6_ID
-1]);
284 if (tuple
->dst
.u
.icmp
.type
< 128
285 || tuple
->dst
.u
.icmp
.type
- 128 >= sizeof(invmap
)
286 || !invmap
[tuple
->dst
.u
.icmp
.type
- 128])
294 static struct ctl_table_header
*icmpv6_sysctl_header
;
295 static struct ctl_table icmpv6_sysctl_table
[] = {
297 .ctl_name
= NET_NF_CONNTRACK_ICMPV6_TIMEOUT
,
298 .procname
= "nf_conntrack_icmpv6_timeout",
299 .data
= &nf_ct_icmpv6_timeout
,
300 .maxlen
= sizeof(unsigned int),
302 .proc_handler
= &proc_dointvec_jiffies
,
308 #endif /* CONFIG_SYSCTL */
310 struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6
=
313 .l4proto
= IPPROTO_ICMPV6
,
315 .pkt_to_tuple
= icmpv6_pkt_to_tuple
,
316 .invert_tuple
= icmpv6_invert_tuple
,
317 .print_tuple
= icmpv6_print_tuple
,
318 .print_conntrack
= icmpv6_print_conntrack
,
319 .packet
= icmpv6_packet
,
321 .error
= icmpv6_error
,
322 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
323 .tuple_to_nfattr
= icmpv6_tuple_to_nfattr
,
324 .nfattr_to_tuple
= icmpv6_nfattr_to_tuple
,
327 .ctl_table_header
= &icmpv6_sysctl_header
,
328 .ctl_table
= icmpv6_sysctl_table
,
332 EXPORT_SYMBOL(nf_conntrack_l4proto_icmpv6
);