]>
Commit | Line | Data |
---|---|---|
9fb9cbb1 YK |
1 | /* |
2 | * Copyright (C)2003,2004 USAGI/WIDE Project | |
3 | * | |
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. | |
7 | * | |
8 | * Author: | |
9 | * Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp> | |
9fb9cbb1 YK |
10 | */ |
11 | ||
12 | #include <linux/types.h> | |
9fb9cbb1 YK |
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> | |
19 | #include <net/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> | |
605dcad6 | 24 | #include <net/netfilter/nf_conntrack_l4proto.h> |
9fb9cbb1 YK |
25 | #include <net/netfilter/nf_conntrack_core.h> |
26 | #include <net/netfilter/ipv6/nf_conntrack_icmpv6.h> | |
f01ffbd6 | 27 | #include <net/netfilter/nf_log.h> |
9fb9cbb1 | 28 | |
933a41e7 | 29 | static unsigned long nf_ct_icmpv6_timeout __read_mostly = 30*HZ; |
9fb9cbb1 | 30 | |
09f263cd JE |
31 | static bool icmpv6_pkt_to_tuple(const struct sk_buff *skb, |
32 | unsigned int dataoff, | |
33 | struct nf_conntrack_tuple *tuple) | |
9fb9cbb1 | 34 | { |
7cc3864d JE |
35 | const struct icmp6hdr *hp; |
36 | struct icmp6hdr _hdr; | |
9fb9cbb1 YK |
37 | |
38 | hp = skb_header_pointer(skb, dataoff, sizeof(_hdr), &_hdr); | |
39 | if (hp == NULL) | |
09f263cd | 40 | return false; |
9fb9cbb1 YK |
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; | |
44 | ||
09f263cd | 45 | return true; |
9fb9cbb1 YK |
46 | } |
47 | ||
c1d10adb | 48 | /* Add 1; spaces filled with 0. */ |
7cc3864d | 49 | static const u_int8_t invmap[] = { |
c1d10adb PNA |
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 | |
54 | }; | |
55 | ||
09f263cd JE |
56 | static bool icmpv6_invert_tuple(struct nf_conntrack_tuple *tuple, |
57 | const struct nf_conntrack_tuple *orig) | |
9fb9cbb1 | 58 | { |
f16c9107 YK |
59 | int type = orig->dst.u.icmp.type - 128; |
60 | if (type < 0 || type >= sizeof(invmap) || !invmap[type]) | |
09f263cd | 61 | return false; |
9fb9cbb1 YK |
62 | |
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; | |
09f263cd | 66 | return true; |
9fb9cbb1 YK |
67 | } |
68 | ||
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) | |
72 | { | |
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)); | |
77 | } | |
78 | ||
9fb9cbb1 YK |
79 | /* Returns verdict for packet, or -1 for invalid. */ |
80 | static int icmpv6_packet(struct nf_conn *ct, | |
81 | const struct sk_buff *skb, | |
82 | unsigned int dataoff, | |
83 | enum ip_conntrack_info ctinfo, | |
76108cea | 84 | u_int8_t pf, |
9fb9cbb1 YK |
85 | unsigned int hooknum) |
86 | { | |
87 | /* Try to delete connection immediately after all replies: | |
1ab1457c YH |
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) */ | |
9fb9cbb1 | 91 | if (CTINFO2DIR(ctinfo) == IP_CT_DIR_REPLY) { |
51091764 | 92 | if (atomic_dec_and_test(&ct->proto.icmp.count)) |
718d4ad9 | 93 | nf_ct_kill_acct(ct, ctinfo, skb); |
9fb9cbb1 YK |
94 | } else { |
95 | atomic_inc(&ct->proto.icmp.count); | |
96 | nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, skb); | |
97 | nf_ct_refresh_acct(ct, ctinfo, skb, nf_ct_icmpv6_timeout); | |
98 | } | |
99 | ||
100 | return NF_ACCEPT; | |
101 | } | |
102 | ||
103 | /* Called when a new connection for this protocol found. */ | |
09f263cd JE |
104 | static bool icmpv6_new(struct nf_conn *ct, const struct sk_buff *skb, |
105 | unsigned int dataoff) | |
9fb9cbb1 | 106 | { |
7cc3864d | 107 | static const u_int8_t valid_new[] = { |
9fb9cbb1 YK |
108 | [ICMPV6_ECHO_REQUEST - 128] = 1, |
109 | [ICMPV6_NI_QUERY - 128] = 1 | |
110 | }; | |
c88130bc | 111 | int type = ct->tuplehash[0].tuple.dst.u.icmp.type - 128; |
9fb9cbb1 | 112 | |
f16c9107 | 113 | if (type < 0 || type >= sizeof(valid_new) || !valid_new[type]) { |
9fb9cbb1 | 114 | /* Can't create a new ICMPv6 `conn' with this. */ |
0d53778e PM |
115 | pr_debug("icmpv6: can't create new conn with type %u\n", |
116 | type + 128); | |
3c9fba65 | 117 | nf_ct_dump_tuple_ipv6(&ct->tuplehash[0].tuple); |
09f263cd | 118 | return false; |
9fb9cbb1 | 119 | } |
c88130bc | 120 | atomic_set(&ct->proto.icmp.count, 0); |
09f263cd | 121 | return true; |
9fb9cbb1 YK |
122 | } |
123 | ||
9fb9cbb1 YK |
124 | static int |
125 | icmpv6_error_message(struct sk_buff *skb, | |
126 | unsigned int icmp6off, | |
127 | enum ip_conntrack_info *ctinfo, | |
128 | unsigned int hooknum) | |
129 | { | |
130 | struct nf_conntrack_tuple intuple, origtuple; | |
7cc3864d JE |
131 | const struct nf_conntrack_tuple_hash *h; |
132 | const struct nf_conntrack_l4proto *inproto; | |
9fb9cbb1 YK |
133 | |
134 | NF_CT_ASSERT(skb->nfct == NULL); | |
135 | ||
9fb9cbb1 | 136 | /* Are they talking about one of our connections? */ |
e2a3123f YK |
137 | if (!nf_ct_get_tuplepr(skb, |
138 | skb_network_offset(skb) | |
139 | + sizeof(struct ipv6hdr) | |
140 | + sizeof(struct icmp6hdr), | |
141 | PF_INET6, &origtuple)) { | |
0d53778e | 142 | pr_debug("icmpv6_error: Can't get tuple\n"); |
9fb9cbb1 YK |
143 | return -NF_ACCEPT; |
144 | } | |
145 | ||
e2a3123f YK |
146 | /* rcu_read_lock()ed by nf_hook_slow */ |
147 | inproto = __nf_ct_l4proto_find(PF_INET6, origtuple.dst.protonum); | |
148 | ||
9fb9cbb1 YK |
149 | /* Ordinarily, we'd expect the inverted tupleproto, but it's |
150 | been preserved inside the ICMP. */ | |
151 | if (!nf_ct_invert_tuple(&intuple, &origtuple, | |
152 | &nf_conntrack_l3proto_ipv6, inproto)) { | |
0d53778e | 153 | pr_debug("icmpv6_error: Can't invert tuple\n"); |
9fb9cbb1 YK |
154 | return -NF_ACCEPT; |
155 | } | |
156 | ||
157 | *ctinfo = IP_CT_RELATED; | |
158 | ||
330f7db5 | 159 | h = nf_conntrack_find_get(&intuple); |
9fb9cbb1 | 160 | if (!h) { |
0d53778e | 161 | pr_debug("icmpv6_error: no match\n"); |
9fb9cbb1 YK |
162 | return -NF_ACCEPT; |
163 | } else { | |
164 | if (NF_CT_DIRECTION(h) == IP_CT_DIR_REPLY) | |
165 | *ctinfo += IP_CT_IS_REPLY; | |
166 | } | |
167 | ||
168 | /* Update skb to refer to this connection */ | |
169 | skb->nfct = &nf_ct_tuplehash_to_ctrack(h)->ct_general; | |
170 | skb->nfctinfo = *ctinfo; | |
171 | return -NF_ACCEPT; | |
172 | } | |
173 | ||
174 | static int | |
175 | icmpv6_error(struct sk_buff *skb, unsigned int dataoff, | |
76108cea | 176 | enum ip_conntrack_info *ctinfo, u_int8_t pf, unsigned int hooknum) |
9fb9cbb1 | 177 | { |
7cc3864d JE |
178 | const struct icmp6hdr *icmp6h; |
179 | struct icmp6hdr _ih; | |
9fb9cbb1 YK |
180 | |
181 | icmp6h = skb_header_pointer(skb, dataoff, sizeof(_ih), &_ih); | |
182 | if (icmp6h == NULL) { | |
183 | if (LOG_INVALID(IPPROTO_ICMPV6)) | |
184 | nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL, | |
185 | "nf_ct_icmpv6: short packet "); | |
186 | return -NF_ACCEPT; | |
187 | } | |
188 | ||
6e23ae2a | 189 | if (nf_conntrack_checksum && hooknum == NF_INET_PRE_ROUTING && |
96f6bf82 | 190 | nf_ip6_checksum(skb, hooknum, dataoff, IPPROTO_ICMPV6)) { |
9fb9cbb1 YK |
191 | nf_log_packet(PF_INET6, 0, skb, NULL, NULL, NULL, |
192 | "nf_ct_icmpv6: ICMPv6 checksum failed\n"); | |
193 | return -NF_ACCEPT; | |
194 | } | |
195 | ||
9fb9cbb1 YK |
196 | /* is not error message ? */ |
197 | if (icmp6h->icmp6_type >= 128) | |
198 | return NF_ACCEPT; | |
199 | ||
200 | return icmpv6_error_message(skb, dataoff, ctinfo, hooknum); | |
201 | } | |
202 | ||
e281db5c | 203 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
c1d10adb PNA |
204 | |
205 | #include <linux/netfilter/nfnetlink.h> | |
206 | #include <linux/netfilter/nfnetlink_conntrack.h> | |
fdf70832 | 207 | static int icmpv6_tuple_to_nlattr(struct sk_buff *skb, |
c1d10adb PNA |
208 | const struct nf_conntrack_tuple *t) |
209 | { | |
77236b6e PM |
210 | NLA_PUT_BE16(skb, CTA_PROTO_ICMPV6_ID, t->src.u.icmp.id); |
211 | NLA_PUT_U8(skb, CTA_PROTO_ICMPV6_TYPE, t->dst.u.icmp.type); | |
212 | NLA_PUT_U8(skb, CTA_PROTO_ICMPV6_CODE, t->dst.u.icmp.code); | |
c1d10adb PNA |
213 | |
214 | return 0; | |
215 | ||
df6fb868 | 216 | nla_put_failure: |
c1d10adb PNA |
217 | return -1; |
218 | } | |
219 | ||
f73e924c PM |
220 | static const struct nla_policy icmpv6_nla_policy[CTA_PROTO_MAX+1] = { |
221 | [CTA_PROTO_ICMPV6_TYPE] = { .type = NLA_U8 }, | |
222 | [CTA_PROTO_ICMPV6_CODE] = { .type = NLA_U8 }, | |
223 | [CTA_PROTO_ICMPV6_ID] = { .type = NLA_U16 }, | |
c1d10adb PNA |
224 | }; |
225 | ||
fdf70832 | 226 | static int icmpv6_nlattr_to_tuple(struct nlattr *tb[], |
c1d10adb PNA |
227 | struct nf_conntrack_tuple *tuple) |
228 | { | |
df6fb868 PM |
229 | if (!tb[CTA_PROTO_ICMPV6_TYPE] |
230 | || !tb[CTA_PROTO_ICMPV6_CODE] | |
231 | || !tb[CTA_PROTO_ICMPV6_ID]) | |
c1d10adb PNA |
232 | return -EINVAL; |
233 | ||
77236b6e PM |
234 | tuple->dst.u.icmp.type = nla_get_u8(tb[CTA_PROTO_ICMPV6_TYPE]); |
235 | tuple->dst.u.icmp.code = nla_get_u8(tb[CTA_PROTO_ICMPV6_CODE]); | |
236 | tuple->src.u.icmp.id = nla_get_be16(tb[CTA_PROTO_ICMPV6_ID]); | |
c1d10adb PNA |
237 | |
238 | if (tuple->dst.u.icmp.type < 128 | |
239 | || tuple->dst.u.icmp.type - 128 >= sizeof(invmap) | |
240 | || !invmap[tuple->dst.u.icmp.type - 128]) | |
241 | return -EINVAL; | |
242 | ||
243 | return 0; | |
244 | } | |
245 | #endif | |
246 | ||
933a41e7 PM |
247 | #ifdef CONFIG_SYSCTL |
248 | static struct ctl_table_header *icmpv6_sysctl_header; | |
249 | static struct ctl_table icmpv6_sysctl_table[] = { | |
250 | { | |
933a41e7 PM |
251 | .procname = "nf_conntrack_icmpv6_timeout", |
252 | .data = &nf_ct_icmpv6_timeout, | |
253 | .maxlen = sizeof(unsigned int), | |
254 | .mode = 0644, | |
255 | .proc_handler = &proc_dointvec_jiffies, | |
256 | }, | |
257 | { | |
258 | .ctl_name = 0 | |
259 | } | |
260 | }; | |
261 | #endif /* CONFIG_SYSCTL */ | |
262 | ||
61075af5 | 263 | struct nf_conntrack_l4proto nf_conntrack_l4proto_icmpv6 __read_mostly = |
9fb9cbb1 YK |
264 | { |
265 | .l3proto = PF_INET6, | |
605dcad6 | 266 | .l4proto = IPPROTO_ICMPV6, |
9fb9cbb1 YK |
267 | .name = "icmpv6", |
268 | .pkt_to_tuple = icmpv6_pkt_to_tuple, | |
269 | .invert_tuple = icmpv6_invert_tuple, | |
270 | .print_tuple = icmpv6_print_tuple, | |
9fb9cbb1 YK |
271 | .packet = icmpv6_packet, |
272 | .new = icmpv6_new, | |
273 | .error = icmpv6_error, | |
e281db5c | 274 | #if defined(CONFIG_NF_CT_NETLINK) || defined(CONFIG_NF_CT_NETLINK_MODULE) |
fdf70832 PM |
275 | .tuple_to_nlattr = icmpv6_tuple_to_nlattr, |
276 | .nlattr_to_tuple = icmpv6_nlattr_to_tuple, | |
f73e924c | 277 | .nla_policy = icmpv6_nla_policy, |
c1d10adb | 278 | #endif |
933a41e7 PM |
279 | #ifdef CONFIG_SYSCTL |
280 | .ctl_table_header = &icmpv6_sysctl_header, | |
281 | .ctl_table = icmpv6_sysctl_table, | |
282 | #endif | |
9fb9cbb1 | 283 | }; |