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 | 73 | |
778d80be YH |
74 | if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL || |
75 | !idev || unlikely(idev->cnf.disable_ipv6)) { | |
a11d206d YH |
76 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS); |
77 | rcu_read_unlock(); | |
1da177e4 LT |
78 | goto out; |
79 | } | |
80 | ||
6b7fdc3a GC |
81 | memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm)); |
82 | ||
1da177e4 LT |
83 | /* |
84 | * Store incoming device index. When the packet will | |
85 | * be queued, we cannot refer to skb->dev anymore. | |
86 | * | |
87 | * BTW, when we send a packet for our own local address on a | |
88 | * non-loopback interface (e.g. ethX), it is being delivered | |
de3cb747 | 89 | * via the loopback interface (lo) here; skb->dev = loopback_dev. |
1da177e4 LT |
90 | * It, however, should be considered as if it is being |
91 | * arrived via the sending interface (ethX), because of the | |
92 | * nature of scoping architecture. --yoshfuji | |
93 | */ | |
7a3025b1 | 94 | IP6CB(skb)->iif = skb->dst ? ip6_dst_idev(skb->dst)->dev->ifindex : dev->ifindex; |
1da177e4 | 95 | |
2889139a | 96 | if (unlikely(!pskb_may_pull(skb, sizeof(*hdr)))) |
1da177e4 LT |
97 | goto err; |
98 | ||
0660e03f | 99 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
100 | |
101 | if (hdr->version != 6) | |
102 | goto err; | |
103 | ||
f630e43a YH |
104 | /* |
105 | * RFC4291 2.5.3 | |
106 | * A packet received on an interface with a destination address | |
107 | * of loopback must be dropped. | |
108 | */ | |
109 | if (!(dev->flags & IFF_LOOPBACK) && | |
110 | ipv6_addr_loopback(&hdr->daddr)) | |
111 | goto err; | |
112 | ||
b0e380b1 | 113 | skb->transport_header = skb->network_header + sizeof(*hdr); |
951dbc8a PM |
114 | IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr); |
115 | ||
1da177e4 LT |
116 | pkt_len = ntohs(hdr->payload_len); |
117 | ||
118 | /* pkt_len may be zero if Jumbo payload option is present */ | |
119 | if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) { | |
60e5c166 MC |
120 | if (pkt_len + sizeof(struct ipv6hdr) > skb->len) { |
121 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INTRUNCATEDPKTS); | |
122 | goto drop; | |
123 | } | |
1da177e4 | 124 | if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) { |
a11d206d | 125 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 LT |
126 | goto drop; |
127 | } | |
0660e03f | 128 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
129 | } |
130 | ||
131 | if (hdr->nexthdr == NEXTHDR_HOP) { | |
e5bbef20 | 132 | if (ipv6_parse_hopopts(skb) < 0) { |
a11d206d YH |
133 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
134 | rcu_read_unlock(); | |
1da177e4 LT |
135 | return 0; |
136 | } | |
1da177e4 LT |
137 | } |
138 | ||
a11d206d YH |
139 | rcu_read_unlock(); |
140 | ||
6e23ae2a PM |
141 | return NF_HOOK(PF_INET6, NF_INET_PRE_ROUTING, skb, dev, NULL, |
142 | ip6_rcv_finish); | |
1da177e4 | 143 | err: |
a11d206d | 144 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 145 | drop: |
a11d206d | 146 | rcu_read_unlock(); |
1da177e4 LT |
147 | kfree_skb(skb); |
148 | out: | |
149 | return 0; | |
150 | } | |
151 | ||
152 | /* | |
153 | * Deliver the packet to the host | |
154 | */ | |
155 | ||
156 | ||
ad643a79 | 157 | static int ip6_input_finish(struct sk_buff *skb) |
1da177e4 LT |
158 | { |
159 | struct inet6_protocol *ipprot; | |
1da177e4 | 160 | unsigned int nhoff; |
69d6da0b | 161 | int nexthdr, raw; |
1da177e4 | 162 | u8 hash; |
a11d206d | 163 | struct inet6_dev *idev; |
1da177e4 | 164 | |
1da177e4 LT |
165 | /* |
166 | * Parse extension headers | |
167 | */ | |
168 | ||
1da177e4 LT |
169 | rcu_read_lock(); |
170 | resubmit: | |
a11d206d | 171 | idev = ip6_dst_idev(skb->dst); |
ea2ae17d | 172 | if (!pskb_pull(skb, skb_transport_offset(skb))) |
1da177e4 | 173 | goto discard; |
951dbc8a | 174 | nhoff = IP6CB(skb)->nhoff; |
d56f90a7 | 175 | nexthdr = skb_network_header(skb)[nhoff]; |
1da177e4 | 176 | |
69d6da0b | 177 | raw = raw6_local_deliver(skb, nexthdr); |
1da177e4 LT |
178 | |
179 | hash = nexthdr & (MAX_INET_PROTOS - 1); | |
180 | if ((ipprot = rcu_dereference(inet6_protos[hash])) != NULL) { | |
181 | int ret; | |
1ab1457c | 182 | |
1da177e4 | 183 | if (ipprot->flags & INET6_PROTO_FINAL) { |
1ab1457c | 184 | struct ipv6hdr *hdr; |
1da177e4 | 185 | |
9fb9cbb1 YK |
186 | /* Free reference early: we don't need it any more, |
187 | and it may hold ip_conntrack module loaded | |
188 | indefinitely. */ | |
189 | nf_reset(skb); | |
190 | ||
d56f90a7 | 191 | skb_postpull_rcsum(skb, skb_network_header(skb), |
cfe1fc77 | 192 | skb_network_header_len(skb)); |
0660e03f | 193 | hdr = ipv6_hdr(skb); |
1da177e4 LT |
194 | if (ipv6_addr_is_multicast(&hdr->daddr) && |
195 | !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, | |
196 | &hdr->saddr) && | |
197 | !ipv6_is_mld(skb, nexthdr)) | |
198 | goto discard; | |
199 | } | |
200 | if (!(ipprot->flags & INET6_PROTO_NOPOLICY) && | |
1ab1457c | 201 | !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) |
1da177e4 | 202 | goto discard; |
1ab1457c | 203 | |
e5bbef20 | 204 | ret = ipprot->handler(skb); |
1da177e4 LT |
205 | if (ret > 0) |
206 | goto resubmit; | |
207 | else if (ret == 0) | |
a11d206d | 208 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS); |
1da177e4 | 209 | } else { |
69d6da0b | 210 | if (!raw) { |
1da177e4 | 211 | if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
a11d206d | 212 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INUNKNOWNPROTOS); |
fad87aca | 213 | icmpv6_send(skb, ICMPV6_PARAMPROB, |
1ab1457c YH |
214 | ICMPV6_UNK_NEXTHDR, nhoff, |
215 | skb->dev); | |
1da177e4 | 216 | } |
fad87aca | 217 | } else |
a11d206d | 218 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDELIVERS); |
fad87aca | 219 | kfree_skb(skb); |
1da177e4 LT |
220 | } |
221 | rcu_read_unlock(); | |
222 | return 0; | |
223 | ||
224 | discard: | |
a11d206d | 225 | IP6_INC_STATS_BH(idev, IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
226 | rcu_read_unlock(); |
227 | kfree_skb(skb); | |
228 | return 0; | |
229 | } | |
230 | ||
231 | ||
232 | int ip6_input(struct sk_buff *skb) | |
233 | { | |
6e23ae2a PM |
234 | return NF_HOOK(PF_INET6, NF_INET_LOCAL_IN, skb, skb->dev, NULL, |
235 | ip6_input_finish); | |
1da177e4 LT |
236 | } |
237 | ||
238 | int ip6_mc_input(struct sk_buff *skb) | |
239 | { | |
240 | struct ipv6hdr *hdr; | |
241 | int deliver; | |
242 | ||
a11d206d | 243 | IP6_INC_STATS_BH(ip6_dst_idev(skb->dst), IPSTATS_MIB_INMCASTPKTS); |
1da177e4 | 244 | |
0660e03f | 245 | hdr = ipv6_hdr(skb); |
4c7966b8 | 246 | deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL); |
1da177e4 | 247 | |
7bc570c8 | 248 | #ifdef CONFIG_IPV6_MROUTE |
1da177e4 | 249 | /* |
7bc570c8 | 250 | * IPv6 multicast router mode is now supported ;) |
1da177e4 | 251 | */ |
53b7997f | 252 | if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding && |
7bc570c8 YH |
253 | likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) { |
254 | /* | |
255 | * Okay, we try to forward - split and duplicate | |
256 | * packets. | |
257 | */ | |
258 | struct sk_buff *skb2; | |
259 | struct inet6_skb_parm *opt = IP6CB(skb); | |
260 | ||
261 | /* Check for MLD */ | |
262 | if (unlikely(opt->ra)) { | |
263 | /* Check if this is a mld message */ | |
264 | u8 *ptr = skb_network_header(skb) + opt->ra; | |
265 | struct icmp6hdr *icmp6; | |
266 | u8 nexthdr = hdr->nexthdr; | |
267 | int offset; | |
268 | ||
269 | /* Check if the value of Router Alert | |
270 | * is for MLD (0x0000). | |
271 | */ | |
272 | if ((ptr[2] | ptr[3]) == 0) { | |
aba6096b YH |
273 | deliver = 0; |
274 | ||
7bc570c8 YH |
275 | if (!ipv6_ext_hdr(nexthdr)) { |
276 | /* BUG */ | |
aba6096b | 277 | goto out; |
7bc570c8 YH |
278 | } |
279 | offset = ipv6_skip_exthdr(skb, sizeof(*hdr), | |
280 | &nexthdr); | |
281 | if (offset < 0) | |
aba6096b | 282 | goto out; |
7bc570c8 YH |
283 | |
284 | if (nexthdr != IPPROTO_ICMPV6) | |
aba6096b | 285 | goto out; |
7bc570c8 YH |
286 | |
287 | if (!pskb_may_pull(skb, (skb_network_header(skb) + | |
288 | offset + 1 - skb->data))) | |
aba6096b | 289 | goto out; |
7bc570c8 YH |
290 | |
291 | icmp6 = (struct icmp6hdr *)(skb_network_header(skb) + offset); | |
292 | ||
293 | switch (icmp6->icmp6_type) { | |
294 | case ICMPV6_MGM_QUERY: | |
295 | case ICMPV6_MGM_REPORT: | |
296 | case ICMPV6_MGM_REDUCTION: | |
297 | case ICMPV6_MLD2_REPORT: | |
aba6096b | 298 | deliver = 1; |
7bc570c8 | 299 | break; |
7bc570c8 | 300 | } |
7bc570c8 YH |
301 | goto out; |
302 | } | |
303 | /* unknown RA - process it normally */ | |
304 | } | |
1da177e4 | 305 | |
7bc570c8 YH |
306 | if (deliver) |
307 | skb2 = skb_clone(skb, GFP_ATOMIC); | |
308 | else { | |
309 | skb2 = skb; | |
310 | skb = NULL; | |
311 | } | |
1ab1457c | 312 | |
7bc570c8 YH |
313 | if (skb2) { |
314 | skb2->dev = skb2->dst->dev; | |
315 | ip6_mr_input(skb2); | |
1da177e4 LT |
316 | } |
317 | } | |
7bc570c8 | 318 | out: |
aba6096b YH |
319 | #endif |
320 | if (likely(deliver)) | |
1da177e4 | 321 | ip6_input(skb); |
aba6096b YH |
322 | else { |
323 | /* discard */ | |
324 | kfree_skb(skb); | |
1da177e4 | 325 | } |
1da177e4 LT |
326 | |
327 | return 0; | |
328 | } |