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22#include <linux/errno.h>
23#include <linux/types.h>
24#include <linux/socket.h>
25#include <linux/sockios.h>
26#include <linux/net.h>
27#include <linux/netdevice.h>
28#include <linux/in6.h>
29#include <linux/icmpv6.h>
30#include <linux/mroute6.h>
31#include <linux/slab.h>
32
33#include <linux/netfilter.h>
34#include <linux/netfilter_ipv6.h>
35
36#include <net/sock.h>
37#include <net/snmp.h>
38
39#include <net/ipv6.h>
40#include <net/protocol.h>
41#include <net/transp_v6.h>
42#include <net/rawv6.h>
43#include <net/ndisc.h>
44#include <net/ip6_route.h>
45#include <net/addrconf.h>
46#include <net/xfrm.h>
47
48
49
50int ip6_rcv_finish(struct sk_buff *skb)
51{
52 if (sysctl_ip_early_demux && !skb_dst(skb)) {
53 const struct inet6_protocol *ipprot;
54
55 ipprot = rcu_dereference(inet6_protos[ipv6_hdr(skb)->nexthdr]);
56 if (ipprot && ipprot->early_demux)
57 ipprot->early_demux(skb);
58 }
59 if (!skb_dst(skb))
60 ip6_route_input(skb);
61
62 return dst_input(skb);
63}
64
65int ipv6_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev)
66{
67 const struct ipv6hdr *hdr;
68 u32 pkt_len;
69 struct inet6_dev *idev;
70 struct net *net = dev_net(skb->dev);
71
72 if (skb->pkt_type == PACKET_OTHERHOST) {
73 kfree_skb(skb);
74 return NET_RX_DROP;
75 }
76
77 rcu_read_lock();
78
79 idev = __in6_dev_get(skb->dev);
80
81 IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_IN, skb->len);
82
83 if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL ||
84 !idev || unlikely(idev->cnf.disable_ipv6)) {
85 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDISCARDS);
86 goto drop;
87 }
88
89 memset(IP6CB(skb), 0, sizeof(struct inet6_skb_parm));
90
91
92
93
94
95
96
97
98
99
100
101
102 IP6CB(skb)->iif = skb_dst(skb) ? ip6_dst_idev(skb_dst(skb))->dev->ifindex : dev->ifindex;
103
104 if (unlikely(!pskb_may_pull(skb, sizeof(*hdr))))
105 goto err;
106
107 hdr = ipv6_hdr(skb);
108
109 if (hdr->version != 6)
110 goto err;
111
112
113
114
115
116
117 if (!(dev->flags & IFF_LOOPBACK) &&
118 ipv6_addr_loopback(&hdr->daddr))
119 goto err;
120
121
122
123
124
125
126
127 if (!(skb->pkt_type == PACKET_LOOPBACK ||
128 dev->flags & IFF_LOOPBACK) &&
129 ipv6_addr_is_multicast(&hdr->daddr) &&
130 IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 1)
131 goto err;
132
133
134
135
136
137
138 if (ipv6_addr_is_multicast(&hdr->daddr) &&
139 IPV6_ADDR_MC_SCOPE(&hdr->daddr) == 0)
140 goto err;
141
142
143
144
145
146
147 if (ipv6_addr_is_multicast(&hdr->saddr))
148 goto err;
149
150 skb->transport_header = skb->network_header + sizeof(*hdr);
151 IP6CB(skb)->nhoff = offsetof(struct ipv6hdr, nexthdr);
152
153 pkt_len = ntohs(hdr->payload_len);
154
155
156 if (pkt_len || hdr->nexthdr != NEXTHDR_HOP) {
157 if (pkt_len + sizeof(struct ipv6hdr) > skb->len) {
158 IP6_INC_STATS_BH(net,
159 idev, IPSTATS_MIB_INTRUNCATEDPKTS);
160 goto drop;
161 }
162 if (pskb_trim_rcsum(skb, pkt_len + sizeof(struct ipv6hdr))) {
163 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
164 goto drop;
165 }
166 hdr = ipv6_hdr(skb);
167 }
168
169 if (hdr->nexthdr == NEXTHDR_HOP) {
170 if (ipv6_parse_hopopts(skb) < 0) {
171 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
172 rcu_read_unlock();
173 return NET_RX_DROP;
174 }
175 }
176
177 rcu_read_unlock();
178
179
180 skb_orphan(skb);
181
182 return NF_HOOK(NFPROTO_IPV6, NF_INET_PRE_ROUTING, skb, dev, NULL,
183 ip6_rcv_finish);
184err:
185 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INHDRERRORS);
186drop:
187 rcu_read_unlock();
188 kfree_skb(skb);
189 return NET_RX_DROP;
190}
191
192
193
194
195
196
197static int ip6_input_finish(struct sk_buff *skb)
198{
199 struct net *net = dev_net(skb_dst(skb)->dev);
200 const struct inet6_protocol *ipprot;
201 struct inet6_dev *idev;
202 unsigned int nhoff;
203 int nexthdr;
204 bool raw;
205
206
207
208
209
210 rcu_read_lock();
211resubmit:
212 idev = ip6_dst_idev(skb_dst(skb));
213 if (!pskb_pull(skb, skb_transport_offset(skb)))
214 goto discard;
215 nhoff = IP6CB(skb)->nhoff;
216 nexthdr = skb_network_header(skb)[nhoff];
217
218 raw = raw6_local_deliver(skb, nexthdr);
219 if ((ipprot = rcu_dereference(inet6_protos[nexthdr])) != NULL) {
220 int ret;
221
222 if (ipprot->flags & INET6_PROTO_FINAL) {
223 const struct ipv6hdr *hdr;
224
225
226
227
228 nf_reset(skb);
229
230 skb_postpull_rcsum(skb, skb_network_header(skb),
231 skb_network_header_len(skb));
232 hdr = ipv6_hdr(skb);
233 if (ipv6_addr_is_multicast(&hdr->daddr) &&
234 !ipv6_chk_mcast_addr(skb->dev, &hdr->daddr,
235 &hdr->saddr) &&
236 !ipv6_is_mld(skb, nexthdr, skb_network_header_len(skb)))
237 goto discard;
238 }
239 if (!(ipprot->flags & INET6_PROTO_NOPOLICY) &&
240 !xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb))
241 goto discard;
242
243 ret = ipprot->handler(skb);
244 if (ret > 0)
245 goto resubmit;
246 else if (ret == 0)
247 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS);
248 } else {
249 if (!raw) {
250 if (xfrm6_policy_check(NULL, XFRM_POLICY_IN, skb)) {
251 IP6_INC_STATS_BH(net, idev,
252 IPSTATS_MIB_INUNKNOWNPROTOS);
253 icmpv6_send(skb, ICMPV6_PARAMPROB,
254 ICMPV6_UNK_NEXTHDR, nhoff);
255 }
256 kfree_skb(skb);
257 } else {
258 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDELIVERS);
259 consume_skb(skb);
260 }
261 }
262 rcu_read_unlock();
263 return 0;
264
265discard:
266 IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_INDISCARDS);
267 rcu_read_unlock();
268 kfree_skb(skb);
269 return 0;
270}
271
272
273int ip6_input(struct sk_buff *skb)
274{
275 return NF_HOOK(NFPROTO_IPV6, NF_INET_LOCAL_IN, skb, skb->dev, NULL,
276 ip6_input_finish);
277}
278
279int ip6_mc_input(struct sk_buff *skb)
280{
281 const struct ipv6hdr *hdr;
282 bool deliver;
283
284 IP6_UPD_PO_STATS_BH(dev_net(skb_dst(skb)->dev),
285 ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_INMCAST,
286 skb->len);
287
288 hdr = ipv6_hdr(skb);
289 deliver = ipv6_chk_mcast_addr(skb->dev, &hdr->daddr, NULL);
290
291#ifdef CONFIG_IPV6_MROUTE
292
293
294
295 if (dev_net(skb->dev)->ipv6.devconf_all->mc_forwarding &&
296 !(ipv6_addr_type(&hdr->daddr) &
297 (IPV6_ADDR_LOOPBACK|IPV6_ADDR_LINKLOCAL)) &&
298 likely(!(IP6CB(skb)->flags & IP6SKB_FORWARDED))) {
299
300
301
302
303 struct sk_buff *skb2;
304 struct inet6_skb_parm *opt = IP6CB(skb);
305
306
307 if (unlikely(opt->flags & IP6SKB_ROUTERALERT)) {
308
309 u8 nexthdr = hdr->nexthdr;
310 __be16 frag_off;
311 int offset;
312
313
314
315
316 if (opt->ra == htons(IPV6_OPT_ROUTERALERT_MLD)) {
317 deliver = false;
318
319 if (!ipv6_ext_hdr(nexthdr)) {
320
321 goto out;
322 }
323 offset = ipv6_skip_exthdr(skb, sizeof(*hdr),
324 &nexthdr, &frag_off);
325 if (offset < 0)
326 goto out;
327
328 if (!ipv6_is_mld(skb, nexthdr, offset))
329 goto out;
330
331 deliver = true;
332 }
333
334 }
335
336 if (deliver)
337 skb2 = skb_clone(skb, GFP_ATOMIC);
338 else {
339 skb2 = skb;
340 skb = NULL;
341 }
342
343 if (skb2) {
344 ip6_mr_input(skb2);
345 }
346 }
347out:
348#endif
349 if (likely(deliver))
350 ip6_input(skb);
351 else {
352
353 kfree_skb(skb);
354 }
355
356 return 0;
357}
358