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/nf_conntrack_timeout.h>
27 #include <net/netfilter/nf_conntrack_zones.h>
28 #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h>
29 #include <net/netfilter/nf_log.h>
31 static const unsigned int nf_ct_icmpv6_timeout = 30*HZ;
33 static inline struct nf_icmp_net *icmpv6_pernet(struct net *net)
35 return &net->ct.nf_ct_proto.icmpv6;
38 static bool icmpv6_pkt_to_tuple(const struct sk_buff *skb,
41 struct nf_conntrack_tuple *tuple)
43 const struct icmp6hdr *hp;
46 hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr);
49 tuple->dst.u.icmp.type = hp->icmp6_type;
50 tuple->src.u.icmp.id = hp->icmp6_identifier;
51 tuple->dst.u.icmp.code = hp->icmp6_code;
56 /* Add 1; spaces filled with 0. */
57 static const u_int8_t invmap[] = {
58 [ICMPV6_ECHO_REQUEST - 128] = ICMPV6_ECHO_REPLY + 1,
59 [ICMPV6_ECHO_REPLY - 128] = ICMPV6_ECHO_REQUEST + 1,
60 [ICMPV6_NI_QUERY - 128] = ICMPV6_NI_REPLY + 1,
61 [ICMPV6_NI_REPLY - 128] = ICMPV6_NI_QUERY + 1
64 static const u_int8_t noct_valid_new[] = {
65 [ICMPV6_MGM_QUERY - 130] = 1,
66 [ICMPV6_MGM_REPORT - 130] = 1,
67 [ICMPV6_MGM_REDUCTION - 130] = 1,
68 [NDISC_ROUTER_SOLICITATION - 130] = 1,
69 [NDISC_ROUTER_ADVERTISEMENT - 130] = 1,
70 [NDISC_NEIGHBOUR_SOLICITATION - 130] = 1,
71 [NDISC_NEIGHBOUR_ADVERTISEMENT - 130] = 1,
72 [ICMPV6_MLD2_REPORT - 130] = 1
75 static bool icmpv6_invert_tuple(struct nf_conntrack_tuple *tuple,
76 const struct nf_conntrack_tuple *orig)
78 int type = orig->dst.u.icmp.type - 128;
79 if (type < 0 || type >= sizeof(invmap) || !invmap[type])
82 tuple->src.u.icmp.id = orig->src.u.icmp.id;
83 tuple->dst.u.icmp.type = invmap[type] - 1;
84 tuple->dst.u.icmp.code = orig->dst.u.icmp.code;
88 static unsigned int *icmpv6_get_timeouts(struct net *net)
90 return &icmpv6_pernet(net)->timeout;
93 /* Returns verdict for packet, or -1 for invalid. */
94 static int icmpv6_packet(struct nf_conn *ct,
95 const struct sk_buff *skb,
97 enum ip_conntrack_info ctinfo)
99 unsigned int *timeout = nf_ct_timeout_lookup(ct);
102 timeout = icmpv6_get_timeouts(nf_ct_net(ct));
104 /* Do not immediately delete the connection after the first
105 successful reply to avoid excessive conntrackd traffic
106 and also to handle correctly ICMP echo reply duplicates. */
107 nf_ct_refresh_acct(ct, ctinfo, skb, *timeout);
112 /* Called when a new connection for this protocol found. */
113 static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb,
114 unsigned int dataoff)
116 static const u_int8_t valid_new[] = {
117 [ICMPV6_ECHO_REQUEST - 128] = 1,
118 [ICMPV6_NI_QUERY - 128] = 1
120 int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128;
122 if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) {
123 /* Can't create a new ICMPv6 `conn' with this. */
124 pr_debug("icmpv6: can't create new conn with type %u\n",
126 nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple);
133 icmpv6_error_message(struct net *net, struct nf_conn *tmpl,
135 unsigned int icmp6off)
137 struct nf_conntrack_tuple intuple, origtuple;
138 const struct nf_conntrack_tuple_hash *h;
139 const struct nf_conntrack_l4proto *inproto;
140 enum ip_conntrack_info ctinfo;
141 struct nf_conntrack_zone tmp;
143 WARN_ON(skb_nfct(skb));
145 /* Are they talking about one of our connections? */
146 if (!nf_ct_get_tuplepr(skb,
147 skb_network_offset(skb)
148 + sizeof(struct ipv6hdr)
149 + sizeof(struct icmp6hdr),
150 PF_INET6, net, &origtuple)) {
151 pr_debug("icmpv6_error: Can't get tuple\n");
155 /* rcu_read_lock()ed by nf_hook_thresh */
156 inproto = __nf_ct_l4proto_find(PF_INET6, origtuple.dst.protonum);
158 /* Ordinarily, we'd expect the inverted tupleproto, but it's
159 been preserved inside the ICMP. */
160 if (!nf_ct_invert_tuple(&intuple, &origtuple, inproto)) {
161 pr_debug("icmpv6_error: Can't invert tuple\n");
165 ctinfo = IP_CT_RELATED;
167 h = nf_conntrack_find_get(net, nf_ct_zone_tmpl(tmpl, skb, &tmp),
170 pr_debug("icmpv6_error: no match\n");
173 if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY)
174 ctinfo += IP_CT_IS_REPLY;
177 /* Update skb to refer to this connection */
178 nf_ct_set(skb, nf_ct_tuplehash_to_ctrack(h), ctinfo);
182 static void icmpv6_error_log(const struct sk_buff *skb, struct net *net,
183 u8 pf, const char *msg)
185 nf_l4proto_log_invalid(skb, net, pf, IPPROTO_ICMPV6, "%s", msg);
189 icmpv6_error(struct net *net, struct nf_conn *tmpl,
190 struct sk_buff *skb, unsigned int dataoff,
191 u8 pf, unsigned int hooknum)
193 const struct icmp6hdr *icmp6h;
197 icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih);
198 if (icmp6h == NULL) {
199 icmpv6_error_log(skb, net, pf, "short packet");
203 if (net->ct.sysctl_checksum && hooknum == NF_INET_PRE_ROUTING &&
204 nf_ip6_checksum(skb, hooknum, dataoff, IPPROTO_ICMPV6)) {
205 icmpv6_error_log(skb, net, pf, "ICMPv6 checksum failed");
209 type = icmp6h->icmp6_type - 130;
210 if (type >= 0 && type < sizeof(noct_valid_new) &&
211 noct_valid_new[type]) {
212 nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
216 /* is not error message ? */
217 if (icmp6h->icmp6_type >= 128)
220 return icmpv6_error_message(net, tmpl, skb, dataoff);
223 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
225 #include <linux/netfilter/nfnetlink.h>
226 #include <linux/netfilter/nfnetlink_conntrack.h>
227 static int icmpv6_tuple_to_nlattr(struct sk_buff *skb,
228 const struct nf_conntrack_tuple *t)
230 if (nla_put_be16(skb, CTA_PROTO_ICMPV6_ID, t->src.u.icmp.id) ||
231 nla_put_u8(skb, CTA_PROTO_ICMPV6_TYPE, t->dst.u.icmp.type) ||
232 nla_put_u8(skb, CTA_PROTO_ICMPV6_CODE, t->dst.u.icmp.code))
233 goto nla_put_failure;
240 static const struct nla_policy icmpv6_nla_policy[CTA_PROTO_MAX+1] = {
241 [CTA_PROTO_ICMPV6_TYPE] = { .type = NLA_U8 },
242 [CTA_PROTO_ICMPV6_CODE] = { .type = NLA_U8 },
243 [CTA_PROTO_ICMPV6_ID] = { .type = NLA_U16 },
246 static int icmpv6_nlattr_to_tuple(struct nlattr *tb[],
247 struct nf_conntrack_tuple *tuple)
249 if (!tb[CTA_PROTO_ICMPV6_TYPE] ||
250 !tb[CTA_PROTO_ICMPV6_CODE] ||
251 !tb[CTA_PROTO_ICMPV6_ID])
254 tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]);
255 tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]);
256 tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]);
258 if (tuple->dst.u.icmp.type < 128 ||
259 tuple->dst.u.icmp.type - 128 >= sizeof(invmap) ||
260 !invmap[tuple->dst.u.icmp.type - 128])
266 static unsigned int icmpv6_nlattr_tuple_size(void)
268 static unsigned int size __read_mostly;
271 size = nla_policy_len(icmpv6_nla_policy, CTA_PROTO_MAX + 1);
277 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
279 #include <linux/netfilter/nfnetlink.h>
280 #include <linux/netfilter/nfnetlink_cttimeout.h>
282 static int icmpv6_timeout_nlattr_to_obj(struct nlattr *tb[],
283 struct net *net, void *data)
285 unsigned int *timeout = data;
286 struct nf_icmp_net *in = icmpv6_pernet(net);
289 timeout = icmpv6_get_timeouts(net);
290 if (tb[CTA_TIMEOUT_ICMPV6_TIMEOUT]) {
292 ntohl(nla_get_be32(tb[CTA_TIMEOUT_ICMPV6_TIMEOUT])) * HZ;
294 /* Set default ICMPv6 timeout. */
295 *timeout = in->timeout;
301 icmpv6_timeout_obj_to_nlattr(struct sk_buff *skb, const void *data)
303 const unsigned int *timeout = data;
305 if (nla_put_be32(skb, CTA_TIMEOUT_ICMPV6_TIMEOUT, htonl(*timeout / HZ)))
306 goto nla_put_failure;
313 static const struct nla_policy
314 icmpv6_timeout_nla_policy[CTA_TIMEOUT_ICMPV6_MAX+1] = {
315 [CTA_TIMEOUT_ICMPV6_TIMEOUT] = { .type = NLA_U32 },
317 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
320 static struct ctl_table icmpv6_sysctl_table[] = {
322 .procname = "nf_conntrack_icmpv6_timeout",
323 .maxlen = sizeof(unsigned int),
325 .proc_handler = proc_dointvec_jiffies,
329 #endif /* CONFIG_SYSCTL */
331 static int icmpv6_kmemdup_sysctl_table(struct nf_proto_net *pn,
332 struct nf_icmp_net *in)
335 pn->ctl_table = kmemdup(icmpv6_sysctl_table,
336 sizeof(icmpv6_sysctl_table),
341 pn->ctl_table[0].data = &in->timeout;
346 static int icmpv6_init_net(struct net *net, u_int16_t proto)
348 struct nf_icmp_net *in = icmpv6_pernet(net);
349 struct nf_proto_net *pn = &in->pn;
351 in->timeout = nf_ct_icmpv6_timeout;
353 return icmpv6_kmemdup_sysctl_table(pn, in);
356 static struct nf_proto_net *icmpv6_get_net_proto(struct net *net)
358 return &net->ct.nf_ct_proto.icmpv6.pn;
361 const struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6 =
364 .l4proto = IPPROTO_ICMPV6,
365 .pkt_to_tuple = icmpv6_pkt_to_tuple,
366 .invert_tuple = icmpv6_invert_tuple,
367 .packet = icmpv6_packet,
369 .error = icmpv6_error,
370 #if IS_ENABLED(CONFIG_NF_CT_NETLINK)
371 .tuple_to_nlattr = icmpv6_tuple_to_nlattr,
372 .nlattr_tuple_size = icmpv6_nlattr_tuple_size,
373 .nlattr_to_tuple = icmpv6_nlattr_to_tuple,
374 .nla_policy = icmpv6_nla_policy,
376 #ifdef CONFIG_NF_CONNTRACK_TIMEOUT
378 .nlattr_to_obj = icmpv6_timeout_nlattr_to_obj,
379 .obj_to_nlattr = icmpv6_timeout_obj_to_nlattr,
380 .nlattr_max = CTA_TIMEOUT_ICMP_MAX,
381 .obj_size = sizeof(unsigned int),
382 .nla_policy = icmpv6_timeout_nla_policy,
384 #endif /* CONFIG_NF_CONNTRACK_TIMEOUT */
385 .init_net = icmpv6_init_net,
386 .get_net_proto = icmpv6_get_net_proto,