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 int nf_ct_icmpv6_timeout __read_mostly = 30*HZ;
31 static bool 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 bool 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 nf_ct_kill_acct(ct, ctinfo, skb);
95 atomic_inc(&ct->proto.icmp.count);
96 nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, ct);
97 nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmpv6_timeout);
103 /* Called when a new connection for this protocol found. */
104 static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb,
105 unsigned int dataoff)
107 static const u_int8_t valid_new[] = {
108 [ICMPV6_ECHO_REQUEST - 128] = 1,
109 [ICMPV6_NI_QUERY - 128] = 1
111 int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128;
113 if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) {
114 /* Can't create a new ICMPv6 `conn' with this. */
115 pr_debug("icmpv6: can't create new conn with type %u\n",
117 nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple);
120 atomic_set(&ct->proto.icmp.count, 0);
125 icmpv6_error_message(struct net *net,
127 unsigned int icmp6off,
128 enum ip_conntrack_info *ctinfo,
129 unsigned int hooknum)
131 struct nf_conntrack_tuple intuple, origtuple;
132 const struct nf_conntrack_tuple_hash *h;
133 const struct nf_conntrack_l4proto *inproto;
135 NF_CT_ASSERT(skb->nfct == NULL);
137 /* Are they talking about one of our connections? */
138 if (!nf_ct_get_tuplepr(skb,
139 skb_network_offset(skb)
140 + sizeof(struct ipv6hdr)
141 + sizeof(struct icmp6hdr),
142 PF_INET6, &origtuple)) {
143 pr_debug("icmpv6_error: Can't get tuple\n");
147 /* rcu_read_lock()ed by nf_hook_slow */
148 inproto = __nf_ct_l4proto_find(PF_INET6, origtuple.dst.protonum);
150 /* Ordinarily, we'd expect the inverted tupleproto, but it's
151 been preserved inside the ICMP. */
152 if (!nf_ct_invert_tuple(&intuple, &origtuple,
153 &nf_conntrack_l3proto_ipv6, inproto)) {
154 pr_debug("icmpv6_error: Can't invert tuple\n");
158 *ctinfo = IP_CT_RELATED;
160 h = nf_conntrack_find_get(net, &intuple);
162 pr_debug("icmpv6_error: no match\n");
165 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
166 *ctinfo += IP_CT_IS_REPLY;
169 /* Update skb to refer to this connection */
170 skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general;
171 skb->nfctinfo = *ctinfo;
176 icmpv6_error(struct net *net, struct sk_buff *skb, unsigned int dataoff,
177 enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum)
179 const struct icmp6hdr *icmp6h;
182 icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
183 if (icmp6h == NULL) {
184 if (LOG_INVALID(net, IPPROTO_ICMPV6))
185 nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL,
186 "nf_ct_icmpv6: short packet ");
190 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
191 nf_ip6_checksum(skb, hooknum, dataoff, IPPROTO_ICMPV6)) {
192 nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL,
193 "nf_ct_icmpv6: ICMPv6 checksum failed\n");
197 /* is not error message ? */
198 if (icmp6h->icmp6_type >= 128)
201 return icmpv6_error_message(net, skb, dataoff, ctinfo, hooknum);
204 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
206 #include <linux/netfilter/nfnetlink.h>
207 #include <linux/netfilter/nfnetlink_conntrack.h>
208 static int icmpv6_tuple_to_nlattr(struct sk_buff *skb,
209 const struct nf_conntrack_tuple *t)
211 NLA_PUT_BE16(skb, CTA_PROTO_ICMPV6_ID, t->src.u.icmp.id);
212 NLA_PUT_U8(skb, CTA_PROTO_ICMPV6_TYPE, t->dst.u.icmp.type);
213 NLA_PUT_U8(skb, CTA_PROTO_ICMPV6_CODE, t->dst.u.icmp.code);
221 static const struct nla_policy icmpv6_nla_policy[CTA_PROTO_MAX+1] = {
222 [CTA_PROTO_ICMPV6_TYPE] = { .type = NLA_U8 },
223 [CTA_PROTO_ICMPV6_CODE] = { .type = NLA_U8 },
224 [CTA_PROTO_ICMPV6_ID] = { .type = NLA_U16 },
227 static int icmpv6_nlattr_to_tuple(struct nlattr *tb[],
228 struct nf_conntrack_tuple *tuple)
230 if (!tb[CTA_PROTO_ICMPV6_TYPE]
231 || !tb[CTA_PROTO_ICMPV6_CODE]
232 || !tb[CTA_PROTO_ICMPV6_ID])
235 tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]);
236 tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]);
237 tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]);
239 if (tuple->dst.u.icmp.type < 128
240 || tuple->dst.u.icmp.type - 128 >= sizeof(invmap)
241 || !invmap[tuple->dst.u.icmp.type - 128])
249 static struct ctl_table_header *icmpv6_sysctl_header;
250 static struct ctl_table icmpv6_sysctl_table[] = {
252 .procname = "nf_conntrack_icmpv6_timeout",
253 .data = &nf_ct_icmpv6_timeout,
254 .maxlen = sizeof(unsigned int),
256 .proc_handler = proc_dointvec_jiffies,
262 #endif /* CONFIG_SYSCTL */
264 struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6 __read_mostly =
267 .l4proto = IPPROTO_ICMPV6,
269 .pkt_to_tuple = icmpv6_pkt_to_tuple,
270 .invert_tuple = icmpv6_invert_tuple,
271 .print_tuple = icmpv6_print_tuple,
272 .packet = icmpv6_packet,
274 .error = icmpv6_error,
275 #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE)
276 .tuple_to_nlattr = icmpv6_tuple_to_nlattr,
277 .nlattr_to_tuple = icmpv6_nlattr_to_tuple,
278 .nla_policy = icmpv6_nla_policy,
281 .ctl_table_header = &icmpv6_sysctl_header,
282 .ctl_table = icmpv6_sysctl_table,