]>
Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * IPv6 input | |
1ab1457c | 3 | * Linux INET6 implementation |
1da177e4 LT |
4 | * |
5 | * Authors: | |
6 | * Pedro Roque <roque@di.fc.ul.pt> | |
7 | * Ian P. Morris <I.P.Morris@soton.ac.uk> | |
8 | * | |
1da177e4 LT |
9 | * Based in linux/net/ipv4/ip_input.c |
10 | * | |
11 | * This program is free software; you can redistribute it and/or | |
12 | * modify it under the terms of the GNU General Public License | |
13 | * as published by the Free Software Foundation; either version | |
14 | * 2 of the License, or (at your option) any later version. | |
15 | */ | |
16 | /* Changes | |
17 | * | |
18 | * Mitsuru KANDA @USAGI and | |
19 | * YOSHIFUJI Hideaki @USAGI: Remove ipv6_parse_exthdrs(). | |
20 | */ | |
21 | ||
22 | #include <linux/errno.h> | |
23 | #include <linux/types.h> | |
24 | #include <linux/socket.h> | |
25 | #include <linux/sockios.h> | |
1da177e4 LT |
26 | #include <linux/net.h> |
27 | #include <linux/netdevice.h> | |
28 | #include <linux/in6.h> | |
29 | #include <linux/icmpv6.h> | |
7bc570c8 | 30 | #include <linux/mroute6.h> |
1da177e4 LT |
31 | |
32 | #include <linux/netfilter.h> | |
33 | #include <linux/netfilter_ipv6.h> | |
34 | ||
35 | #include <net/sock.h> | |
36 | #include <net/snmp.h> | |
37 | ||
38 | #include <net/ipv6.h> | |
39 | #include <net/protocol.h> | |
40 | #include <net/transp_v6.h> | |
41 | #include <net/rawv6.h> | |
42 | #include <net/ndisc.h> | |
43 | #include <net/ip6_route.h> | |
44 | #include <net/addrconf.h> | |
45 | #include <net/xfrm.h> | |
46 | ||
47 | ||
48 | ||
1ab1457c | 49 | inline int ip6_rcv_finish( struct sk_buff *skb) |
1da177e4 LT |
50 | { |
51 | if (skb->dst == NULL) | |
52 | ip6_route_input(skb); | |
53 | ||
54 | return dst_input(skb); | |
55 | } | |
56 | ||
f2ccd8fa | 57 | int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) |
1da177e4 LT |
58 | { |
59 | struct ipv6hdr *hdr; | |
60 | u32 pkt_len; | |
a11d206d | 61 | struct inet6_dev *idev; |
1da177e4 | 62 | |
a11d206d YH |
63 | if (skb->pkt_type == PACKET_OTHERHOST) { |
64 | kfree_skb(skb); | |
65 | return 0; | |
66 | } | |
67 | ||
68 | rcu_read_lock(); | |
1da177e4 | 69 | |
a11d206d YH |
70 | idev = __in6_dev_get(skb->dev); |
71 | ||
72 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INRECEIVES); | |
1da177e4 LT |
73 | |
74 | if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) { | |
a11d206d YH |
75 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS); |
76 | rcu_read_unlock(); | |
1da177e4 LT |
77 | goto out; |
78 | } | |
79 | ||
6b7fdc3a GC |
80 | memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); |
81 | ||
1da177e4 LT |
82 | /* |
83 | * Store incoming device index. When the packet will | |
84 | * be queued, we cannot refer to skb->dev anymore. | |
85 | * | |
86 | * BTW, when we send a packet for our own local address on a | |
87 | * non-loopback interface (e.g. ethX), it is being delivered | |
de3cb747 | 88 | * via the loopback interface (lo) here; skb->dev = loopback_dev. |
1da177e4 LT |
89 | * It, however, should be considered as if it is being |
90 | * arrived via the sending interface (ethX), because of the | |
91 | * nature of scoping architecture. --yoshfuji | |
92 | */ | |
7a3025b1 | 93 | IP6CB(skb)->iif = skb->dst ? ip6_dst_idev(skb->dst)->dev->ifindex : dev->ifindex; |
1da177e4 | 94 | |
2889139a | 95 | if (unlikely(!pskb_may_pull(skb, sizeof(*hdr)))) |
1da177e4 LT |
96 | goto err; |
97 | ||
0660e03f | 98 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
99 | |
100 | if (hdr->version != 6) | |
101 | goto err; | |
102 | ||
f630e43a YH |
103 | /* |
104 | * RFC4291 2.5.3 | |
105 | * A packet received on an interface with a destination address | |
106 | * of loopback must be dropped. | |
107 | */ | |
108 | if (!(dev->flags & IFF_LOOPBACK) && | |
109 | ipv6_addr_loopback(&hdr->daddr)) | |
110 | goto err; | |
111 | ||
b0e380b1 | 112 | skb->transport_header = skb->network_header + sizeof(*hdr); |
951dbc8a PM |
113 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
114 | ||
1da177e4 LT |
115 | pkt_len = ntohs(hdr->payload_len); |
116 | ||
117 | /* pkt_len may be zero if Jumbo payload option is present */ | |
118 | if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { | |
60e5c166 MC |
119 | if (pkt_len + sizeof(struct ipv6hdr) > skb->len) { |
120 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INTRUNCATEDPKTS); | |
121 | goto drop; | |
122 | } | |
1da177e4 | 123 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) { |
a11d206d | 124 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
125 | goto drop; |
126 | } | |
0660e03f | 127 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
128 | } |
129 | ||
130 | if (hdr->nexthdr == NEXTHDR_HOP) { | |
e5bbef20 | 131 | if (ipv6_parse_hopopts(skb) < 0) { |
a11d206d YH |
132 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
133 | rcu_read_unlock(); | |
1da177e4 LT |
134 | return 0; |
135 | } | |
1da177e4 LT |
136 | } |
137 | ||
a11d206d YH |
138 | rcu_read_unlock(); |
139 | ||
6e23ae2a PM |
140 | return NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, dev, NULL, |
141 | ip6_rcv_finish); | |
1da177e4 | 142 | err: |
a11d206d | 143 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 144 | drop: |
a11d206d | 145 | rcu_read_unlock(); |
1da177e4 LT |
146 | kfree_skb(skb); |
147 | out: | |
148 | return 0; | |
149 | } | |
150 | ||
151 | /* | |
152 | * Deliver the packet to the host | |
153 | */ | |
154 | ||
155 | ||
ad643a79 | 156 | static int ip6_input_finish(struct sk_buff *skb) |
1da177e4 LT |
157 | { |
158 | struct inet6_protocol *ipprot; | |
1da177e4 | 159 | unsigned int nhoff; |
69d6da0b | 160 | int nexthdr, raw; |
1da177e4 | 161 | u8 hash; |
a11d206d | 162 | struct inet6_dev *idev; |
1da177e4 | 163 | |
1da177e4 LT |
164 | /* |
165 | * Parse extension headers | |
166 | */ | |
167 | ||
1da177e4 LT |
168 | rcu_read_lock(); |
169 | resubmit: | |
a11d206d | 170 | idev = ip6_dst_idev(skb->dst); |
ea2ae17d | 171 | if (!pskb_pull(skb, skb_transport_offset(skb))) |
1da177e4 | 172 | goto discard; |
951dbc8a | 173 | nhoff = IP6CB(skb)->nhoff; |
d56f90a7 | 174 | nexthdr = skb_network_header(skb)[nhoff]; |
1da177e4 | 175 | |
69d6da0b | 176 | raw = raw6_local_deliver(skb, nexthdr); |
1da177e4 LT |
177 | |
178 | hash = nexthdr & (MAX_INET_PROTOS - 1); | |
179 | if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) { | |
180 | int ret; | |
1ab1457c | 181 | |
1da177e4 | 182 | if (ipprot->flags & INET6_PROTO_FINAL) { |
1ab1457c | 183 | struct ipv6hdr *hdr; |
1da177e4 | 184 | |
9fb9cbb1 YK |
185 | /* Free reference early: we don't need it any more, |
186 | and it may hold ip_conntrack module loaded | |
187 | indefinitely. */ | |
188 | nf_reset(skb); | |
189 | ||
d56f90a7 | 190 | skb_postpull_rcsum(skb, skb_network_header(skb), |
cfe1fc77 | 191 | skb_network_header_len(skb)); |
0660e03f | 192 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
193 | if (ipv6_addr_is_multicast(&hdr->daddr) && |
194 | !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, | |
195 | &hdr->saddr) && | |
196 | !ipv6_is_mld(skb, nexthdr)) | |
197 | goto discard; | |
198 | } | |
199 | if (!(ipprot->flags & INET6_PROTO_NOPOLICY) && | |
1ab1457c | 200 | !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
1da177e4 | 201 | goto discard; |
1ab1457c | 202 | |
e5bbef20 | 203 | ret = ipprot->handler(skb); |
1da177e4 LT |
204 | if (ret > 0) |
205 | goto resubmit; | |
206 | else if (ret == 0) | |
a11d206d | 207 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS); |
1da177e4 | 208 | } else { |
69d6da0b | 209 | if (!raw) { |
1da177e4 | 210 | if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
a11d206d | 211 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INUNKNOWNPROTOS); |
fad87aca | 212 | icmpv6_send(skb, ICMPV6_PARAMPROB, |
1ab1457c YH |
213 | ICMPV6_UNK_NEXTHDR, nhoff, |
214 | skb->dev); | |
1da177e4 | 215 | } |
fad87aca | 216 | } else |
a11d206d | 217 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS); |
fad87aca | 218 | kfree_skb(skb); |
1da177e4 LT |
219 | } |
220 | rcu_read_unlock(); | |
221 | return 0; | |
222 | ||
223 | discard: | |
a11d206d | 224 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
225 | rcu_read_unlock(); |
226 | kfree_skb(skb); | |
227 | return 0; | |
228 | } | |
229 | ||
230 | ||
231 | int ip6_input(struct sk_buff *skb) | |
232 | { | |
6e23ae2a PM |
233 | return NF_HOOK(PF_INET6, NF_INET_LOCAL_IN, skb, skb->dev, NULL, |
234 | ip6_input_finish); | |
1da177e4 LT |
235 | } |
236 | ||
237 | int ip6_mc_input(struct sk_buff *skb) | |
238 | { | |
239 | struct ipv6hdr *hdr; | |
240 | int deliver; | |
241 | ||
a11d206d | 242 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INMCASTPKTS); |
1da177e4 | 243 | |
0660e03f | 244 | hdr = ipv6_hdr(skb); |
4c7966b8 | 245 | deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL); |
1da177e4 | 246 | |
7bc570c8 | 247 | #ifdef CONFIG_IPV6_MROUTE |
1da177e4 | 248 | /* |
7bc570c8 | 249 | * IPv6 multicast router mode is now supported ;) |
1da177e4 | 250 | */ |
7bc570c8 YH |
251 | if (ipv6_devconf.mc_forwarding && |
252 | likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) { | |
253 | /* | |
254 | * Okay, we try to forward - split and duplicate | |
255 | * packets. | |
256 | */ | |
257 | struct sk_buff *skb2; | |
258 | struct inet6_skb_parm *opt = IP6CB(skb); | |
259 | ||
260 | /* Check for MLD */ | |
261 | if (unlikely(opt->ra)) { | |
262 | /* Check if this is a mld message */ | |
263 | u8 *ptr = skb_network_header(skb) + opt->ra; | |
264 | struct icmp6hdr *icmp6; | |
265 | u8 nexthdr = hdr->nexthdr; | |
266 | int offset; | |
267 | ||
268 | /* Check if the value of Router Alert | |
269 | * is for MLD (0x0000). | |
270 | */ | |
271 | if ((ptr[2] | ptr[3]) == 0) { | |
aba6096b YH |
272 | deliver = 0; |
273 | ||
7bc570c8 YH |
274 | if (!ipv6_ext_hdr(nexthdr)) { |
275 | /* BUG */ | |
aba6096b | 276 | goto out; |
7bc570c8 YH |
277 | } |
278 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), | |
279 | &nexthdr); | |
280 | if (offset < 0) | |
aba6096b | 281 | goto out; |
7bc570c8 YH |
282 | |
283 | if (nexthdr != IPPROTO_ICMPV6) | |
aba6096b | 284 | goto out; |
7bc570c8 YH |
285 | |
286 | if (!pskb_may_pull(skb, (skb_network_header(skb) + | |
287 | offset + 1 - skb->data))) | |
aba6096b | 288 | goto out; |
7bc570c8 YH |
289 | |
290 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); | |
291 | ||
292 | switch (icmp6->icmp6_type) { | |
293 | case ICMPV6_MGM_QUERY: | |
294 | case ICMPV6_MGM_REPORT: | |
295 | case ICMPV6_MGM_REDUCTION: | |
296 | case ICMPV6_MLD2_REPORT: | |
aba6096b | 297 | deliver = 1; |
7bc570c8 | 298 | break; |
7bc570c8 | 299 | } |
7bc570c8 YH |
300 | goto out; |
301 | } | |
302 | /* unknown RA - process it normally */ | |
303 | } | |
1da177e4 | 304 | |
7bc570c8 YH |
305 | if (deliver) |
306 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
307 | else { | |
308 | skb2 = skb; | |
309 | skb = NULL; | |
310 | } | |
1ab1457c | 311 | |
7bc570c8 YH |
312 | if (skb2) { |
313 | skb2->dev = skb2->dst->dev; | |
314 | ip6_mr_input(skb2); | |
1da177e4 LT |
315 | } |
316 | } | |
7bc570c8 | 317 | out: |
aba6096b YH |
318 | #endif |
319 | if (likely(deliver)) | |
1da177e4 | 320 | ip6_input(skb); |
aba6096b YH |
321 | else { |
322 | /* discard */ | |
323 | kfree_skb(skb); | |
1da177e4 | 324 | } |
1da177e4 LT |
325 | |
326 | return 0; | |
327 | } |