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>
27 #include <net/netfilter/nf_log.h>
29 static unsigned long nf_ct_icmpv6_timeout __read_mostly
= 30*HZ
;
31 static int icmpv6_pkt_to_tuple(const struct sk_buff
*skb
,
33 struct nf_conntrack_tuple
*tuple
)
35 const struct icmp6hdr
*hp
;
38 hp
= skb_header_pointer(skb
, dataoff
, sizeof(_hdr
), &_hdr
);
41 tuple
->dst
.u
.icmp
.type
= hp
->icmp6_type
;
42 tuple
->src
.u
.icmp
.id
= hp
->icmp6_identifier
;
43 tuple
->dst
.u
.icmp
.code
= hp
->icmp6_code
;
48 /* Add 1; spaces filled with 0. */
49 static const u_int8_t invmap
[] = {
50 [ICMPV6_ECHO_REQUEST
- 128] = ICMPV6_ECHO_REPLY
+ 1,
51 [ICMPV6_ECHO_REPLY
- 128] = ICMPV6_ECHO_REQUEST
+ 1,
52 [ICMPV6_NI_QUERY
- 128] = ICMPV6_NI_QUERY
+ 1,
53 [ICMPV6_NI_REPLY
- 128] = ICMPV6_NI_REPLY
+1
56 static int icmpv6_invert_tuple(struct nf_conntrack_tuple
*tuple
,
57 const struct nf_conntrack_tuple
*orig
)
59 int type
= orig
->dst
.u
.icmp
.type
- 128;
60 if (type
< 0 || type
>= sizeof(invmap
) || !invmap
[type
])
63 tuple
->src
.u
.icmp
.id
= orig
->src
.u
.icmp
.id
;
64 tuple
->dst
.u
.icmp
.type
= invmap
[type
] - 1;
65 tuple
->dst
.u
.icmp
.code
= orig
->dst
.u
.icmp
.code
;
69 /* Print out the per-protocol part of the tuple. */
70 static int icmpv6_print_tuple(struct seq_file
*s
,
71 const struct nf_conntrack_tuple
*tuple
)
73 return seq_printf(s
, "type=%u code=%u id=%u ",
74 tuple
->dst
.u
.icmp
.type
,
75 tuple
->dst
.u
.icmp
.code
,
76 ntohs(tuple
->src
.u
.icmp
.id
));
79 /* Returns verdict for packet, or -1 for invalid. */
80 static int icmpv6_packet(struct nf_conn
*ct
,
81 const struct sk_buff
*skb
,
83 enum ip_conntrack_info ctinfo
,
87 /* Try to delete connection immediately after all replies:
88 won't actually vanish as we still have skb, and del_timer
89 means this will only run once even if count hits zero twice
90 (theoretically possible with SMP) */
91 if (CTINFO2DIR(ctinfo
) == IP_CT_DIR_REPLY
) {
92 if (atomic_dec_and_test(&ct
->proto
.icmp
.count
)
93 && del_timer(&ct
->timeout
))
94 ct
->timeout
.function((unsigned long)ct
);
96 atomic_inc(&ct
->proto
.icmp
.count
);
97 nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE
, skb
);
98 nf_ct_refresh_acct(ct
, ctinfo
, skb
, nf_ct_icmpv6_timeout
);
104 /* Called when a new connection for this protocol found. */
105 static int icmpv6_new(struct nf_conn
*ct
,
106 const struct sk_buff
*skb
,
107 unsigned int dataoff
)
109 static const u_int8_t valid_new
[] = {
110 [ICMPV6_ECHO_REQUEST
- 128] = 1,
111 [ICMPV6_NI_QUERY
- 128] = 1
113 int type
= ct
->tuplehash
[0].tuple
.dst
.u
.icmp
.type
- 128;
115 if (type
< 0 || type
>= sizeof(valid_new
) || !valid_new
[type
]) {
116 /* Can't create a new ICMPv6 `conn' with this. */
117 pr_debug("icmpv6: can't create new conn with type %u\n",
119 NF_CT_DUMP_TUPLE(&ct
->tuplehash
[0].tuple
);
122 atomic_set(&ct
->proto
.icmp
.count
, 0);
127 icmpv6_error_message(struct sk_buff
*skb
,
128 unsigned int icmp6off
,
129 enum ip_conntrack_info
*ctinfo
,
130 unsigned int hooknum
)
132 struct nf_conntrack_tuple intuple
, origtuple
;
133 const struct nf_conntrack_tuple_hash
*h
;
134 const struct nf_conntrack_l4proto
*inproto
;
136 NF_CT_ASSERT(skb
->nfct
== NULL
);
138 /* Are they talking about one of our connections? */
139 if (!nf_ct_get_tuplepr(skb
,
140 skb_network_offset(skb
)
141 + sizeof(struct ipv6hdr
)
142 + sizeof(struct icmp6hdr
),
143 PF_INET6
, &origtuple
)) {
144 pr_debug("icmpv6_error: Can't get tuple\n");
148 /* rcu_read_lock()ed by nf_hook_slow */
149 inproto
= __nf_ct_l4proto_find(PF_INET6
, origtuple
.dst
.protonum
);
151 /* Ordinarily, we'd expect the inverted tupleproto, but it's
152 been preserved inside the ICMP. */
153 if (!nf_ct_invert_tuple(&intuple
, &origtuple
,
154 &nf_conntrack_l3proto_ipv6
, inproto
)) {
155 pr_debug("icmpv6_error: Can't invert tuple\n");
159 *ctinfo
= IP_CT_RELATED
;
161 h
= nf_conntrack_find_get(&intuple
);
163 pr_debug("icmpv6_error: no match\n");
166 if (NF_CT_DIRECTION(h
) == IP_CT_DIR_REPLY
)
167 *ctinfo
+= IP_CT_IS_REPLY
;
170 /* Update skb to refer to this connection */
171 skb
->nfct
= &nf_ct_tuplehash_to_ctrack(h
)->ct_general
;
172 skb
->nfctinfo
= *ctinfo
;
177 icmpv6_error(struct sk_buff
*skb
, unsigned int dataoff
,
178 enum ip_conntrack_info
*ctinfo
, int pf
, unsigned int hooknum
)
180 const struct icmp6hdr
*icmp6h
;
183 icmp6h
= skb_header_pointer(skb
, dataoff
, sizeof(_ih
), &_ih
);
184 if (icmp6h
== NULL
) {
185 if (LOG_INVALID(IPPROTO_ICMPV6
))
186 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
187 "nf_ct_icmpv6: short packet ");
191 if (nf_conntrack_checksum
&& hooknum
== NF_INET_PRE_ROUTING
&&
192 nf_ip6_checksum(skb
, hooknum
, dataoff
, IPPROTO_ICMPV6
)) {
193 nf_log_packet(PF_INET6
, 0, skb
, NULL
, NULL
, NULL
,
194 "nf_ct_icmpv6: ICMPv6 checksum failed\n");
198 /* is not error message ? */
199 if (icmp6h
->icmp6_type
>= 128)
202 return icmpv6_error_message(skb
, dataoff
, ctinfo
, hooknum
);
205 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
207 #include <linux/netfilter/nfnetlink.h>
208 #include <linux/netfilter/nfnetlink_conntrack.h>
209 static int icmpv6_tuple_to_nlattr(struct sk_buff
*skb
,
210 const struct nf_conntrack_tuple
*t
)
212 NLA_PUT_BE16(skb
, CTA_PROTO_ICMPV6_ID
, t
->src
.u
.icmp
.id
);
213 NLA_PUT_U8(skb
, CTA_PROTO_ICMPV6_TYPE
, t
->dst
.u
.icmp
.type
);
214 NLA_PUT_U8(skb
, CTA_PROTO_ICMPV6_CODE
, t
->dst
.u
.icmp
.code
);
222 static const struct nla_policy icmpv6_nla_policy
[CTA_PROTO_MAX
+1] = {
223 [CTA_PROTO_ICMPV6_TYPE
] = { .type
= NLA_U8
},
224 [CTA_PROTO_ICMPV6_CODE
] = { .type
= NLA_U8
},
225 [CTA_PROTO_ICMPV6_ID
] = { .type
= NLA_U16
},
228 static int icmpv6_nlattr_to_tuple(struct nlattr
*tb
[],
229 struct nf_conntrack_tuple
*tuple
)
231 if (!tb
[CTA_PROTO_ICMPV6_TYPE
]
232 || !tb
[CTA_PROTO_ICMPV6_CODE
]
233 || !tb
[CTA_PROTO_ICMPV6_ID
])
236 tuple
->dst
.u
.icmp
.type
= nla_get_u8(tb
[CTA_PROTO_ICMPV6_TYPE
]);
237 tuple
->dst
.u
.icmp
.code
= nla_get_u8(tb
[CTA_PROTO_ICMPV6_CODE
]);
238 tuple
->src
.u
.icmp
.id
= nla_get_be16(tb
[CTA_PROTO_ICMPV6_ID
]);
240 if (tuple
->dst
.u
.icmp
.type
< 128
241 || tuple
->dst
.u
.icmp
.type
- 128 >= sizeof(invmap
)
242 || !invmap
[tuple
->dst
.u
.icmp
.type
- 128])
250 static struct ctl_table_header
*icmpv6_sysctl_header
;
251 static struct ctl_table icmpv6_sysctl_table
[] = {
253 .procname
= "nf_conntrack_icmpv6_timeout",
254 .data
= &nf_ct_icmpv6_timeout
,
255 .maxlen
= sizeof(unsigned int),
257 .proc_handler
= &proc_dointvec_jiffies
,
263 #endif /* CONFIG_SYSCTL */
265 struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6 __read_mostly
=
268 .l4proto
= IPPROTO_ICMPV6
,
270 .pkt_to_tuple
= icmpv6_pkt_to_tuple
,
271 .invert_tuple
= icmpv6_invert_tuple
,
272 .print_tuple
= icmpv6_print_tuple
,
273 .packet
= icmpv6_packet
,
275 .error
= icmpv6_error
,
276 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
277 .tuple_to_nlattr
= icmpv6_tuple_to_nlattr
,
278 .nlattr_to_tuple
= icmpv6_nlattr_to_tuple
,
279 .nla_policy
= icmpv6_nla_policy
,
282 .ctl_table_header
= &icmpv6_sysctl_header
,
283 .ctl_table
= icmpv6_sysctl_table
,