Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * INET An implementation of the TCP/IP protocol suite for the LINUX | |
3 | * operating system. INET is implemented using the BSD Socket | |
4 | * interface as the means of communication with the user level. | |
5 | * | |
6 | * The Internet Protocol (IP) module. | |
7 | * | |
02c30a84 | 8 | * Authors: Ross Biro |
1da177e4 LT |
9 | * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
10 | * Donald Becker, <becker@super.org> | |
113aa838 | 11 | * Alan Cox, <alan@lxorguk.ukuu.org.uk> |
1da177e4 LT |
12 | * Richard Underwood |
13 | * Stefan Becker, <stefanb@yello.ping.de> | |
14 | * Jorge Cwik, <jorge@laser.satlink.net> | |
15 | * Arnt Gulbrandsen, <agulbra@nvg.unit.no> | |
e905a9ed | 16 | * |
1da177e4 LT |
17 | * |
18 | * Fixes: | |
19 | * Alan Cox : Commented a couple of minor bits of surplus code | |
20 | * Alan Cox : Undefining IP_FORWARD doesn't include the code | |
21 | * (just stops a compiler warning). | |
22 | * Alan Cox : Frames with >=MAX_ROUTE record routes, strict routes or loose routes | |
23 | * are junked rather than corrupting things. | |
24 | * Alan Cox : Frames to bad broadcast subnets are dumped | |
25 | * We used to process them non broadcast and | |
26 | * boy could that cause havoc. | |
27 | * Alan Cox : ip_forward sets the free flag on the | |
28 | * new frame it queues. Still crap because | |
29 | * it copies the frame but at least it | |
30 | * doesn't eat memory too. | |
31 | * Alan Cox : Generic queue code and memory fixes. | |
32 | * Fred Van Kempen : IP fragment support (borrowed from NET2E) | |
33 | * Gerhard Koerting: Forward fragmented frames correctly. | |
34 | * Gerhard Koerting: Fixes to my fix of the above 8-). | |
35 | * Gerhard Koerting: IP interface addressing fix. | |
36 | * Linus Torvalds : More robustness checks | |
37 | * Alan Cox : Even more checks: Still not as robust as it ought to be | |
38 | * Alan Cox : Save IP header pointer for later | |
39 | * Alan Cox : ip option setting | |
40 | * Alan Cox : Use ip_tos/ip_ttl settings | |
41 | * Alan Cox : Fragmentation bogosity removed | |
42 | * (Thanks to Mark.Bush@prg.ox.ac.uk) | |
43 | * Dmitry Gorodchanin : Send of a raw packet crash fix. | |
44 | * Alan Cox : Silly ip bug when an overlength | |
45 | * fragment turns up. Now frees the | |
46 | * queue. | |
47 | * Linus Torvalds/ : Memory leakage on fragmentation | |
48 | * Alan Cox : handling. | |
49 | * Gerhard Koerting: Forwarding uses IP priority hints | |
50 | * Teemu Rantanen : Fragment problems. | |
51 | * Alan Cox : General cleanup, comments and reformat | |
52 | * Alan Cox : SNMP statistics | |
53 | * Alan Cox : BSD address rule semantics. Also see | |
54 | * UDP as there is a nasty checksum issue | |
55 | * if you do things the wrong way. | |
56 | * Alan Cox : Always defrag, moved IP_FORWARD to the config.in file | |
57 | * Alan Cox : IP options adjust sk->priority. | |
58 | * Pedro Roque : Fix mtu/length error in ip_forward. | |
59 | * Alan Cox : Avoid ip_chk_addr when possible. | |
60 | * Richard Underwood : IP multicasting. | |
61 | * Alan Cox : Cleaned up multicast handlers. | |
62 | * Alan Cox : RAW sockets demultiplex in the BSD style. | |
63 | * Gunther Mayer : Fix the SNMP reporting typo | |
64 | * Alan Cox : Always in group 224.0.0.1 | |
65 | * Pauline Middelink : Fast ip_checksum update when forwarding | |
66 | * Masquerading support. | |
67 | * Alan Cox : Multicast loopback error for 224.0.0.1 | |
68 | * Alan Cox : IP_MULTICAST_LOOP option. | |
69 | * Alan Cox : Use notifiers. | |
70 | * Bjorn Ekwall : Removed ip_csum (from slhc.c too) | |
71 | * Bjorn Ekwall : Moved ip_fast_csum to ip.h (inline!) | |
72 | * Stefan Becker : Send out ICMP HOST REDIRECT | |
73 | * Arnt Gulbrandsen : ip_build_xmit | |
74 | * Alan Cox : Per socket routing cache | |
75 | * Alan Cox : Fixed routing cache, added header cache. | |
76 | * Alan Cox : Loopback didn't work right in original ip_build_xmit - fixed it. | |
77 | * Alan Cox : Only send ICMP_REDIRECT if src/dest are the same net. | |
78 | * Alan Cox : Incoming IP option handling. | |
79 | * Alan Cox : Set saddr on raw output frames as per BSD. | |
80 | * Alan Cox : Stopped broadcast source route explosions. | |
81 | * Alan Cox : Can disable source routing | |
82 | * Takeshi Sone : Masquerading didn't work. | |
83 | * Dave Bonn,Alan Cox : Faster IP forwarding whenever possible. | |
84 | * Alan Cox : Memory leaks, tramples, misc debugging. | |
85 | * Alan Cox : Fixed multicast (by popular demand 8)) | |
86 | * Alan Cox : Fixed forwarding (by even more popular demand 8)) | |
87 | * Alan Cox : Fixed SNMP statistics [I think] | |
88 | * Gerhard Koerting : IP fragmentation forwarding fix | |
89 | * Alan Cox : Device lock against page fault. | |
90 | * Alan Cox : IP_HDRINCL facility. | |
91 | * Werner Almesberger : Zero fragment bug | |
92 | * Alan Cox : RAW IP frame length bug | |
93 | * Alan Cox : Outgoing firewall on build_xmit | |
94 | * A.N.Kuznetsov : IP_OPTIONS support throughout the kernel | |
95 | * Alan Cox : Multicast routing hooks | |
96 | * Jos Vos : Do accounting *before* call_in_firewall | |
97 | * Willy Konynenberg : Transparent proxying support | |
98 | * | |
e905a9ed | 99 | * |
1da177e4 LT |
100 | * |
101 | * To Fix: | |
102 | * IP fragmentation wants rewriting cleanly. The RFC815 algorithm is much more efficient | |
103 | * and could be made very efficient with the addition of some virtual memory hacks to permit | |
104 | * the allocation of a buffer that can then be 'grown' by twiddling page tables. | |
e905a9ed | 105 | * Output fragmentation wants updating along with the buffer management to use a single |
1da177e4 LT |
106 | * interleaved copy algorithm so that fragmenting has a one copy overhead. Actual packet |
107 | * output should probably do its own fragmentation at the UDP/RAW layer. TCP shouldn't cause | |
108 | * fragmentation anyway. | |
109 | * | |
110 | * This program is free software; you can redistribute it and/or | |
111 | * modify it under the terms of the GNU General Public License | |
112 | * as published by the Free Software Foundation; either version | |
113 | * 2 of the License, or (at your option) any later version. | |
114 | */ | |
115 | ||
afd46503 JP |
116 | #define pr_fmt(fmt) "IPv4: " fmt |
117 | ||
1da177e4 LT |
118 | #include <linux/module.h> |
119 | #include <linux/types.h> | |
120 | #include <linux/kernel.h> | |
121 | #include <linux/string.h> | |
122 | #include <linux/errno.h> | |
5a0e3ad6 | 123 | #include <linux/slab.h> |
1da177e4 LT |
124 | |
125 | #include <linux/net.h> | |
126 | #include <linux/socket.h> | |
127 | #include <linux/sockios.h> | |
128 | #include <linux/in.h> | |
129 | #include <linux/inet.h> | |
14c85021 | 130 | #include <linux/inetdevice.h> |
1da177e4 LT |
131 | #include <linux/netdevice.h> |
132 | #include <linux/etherdevice.h> | |
133 | ||
134 | #include <net/snmp.h> | |
135 | #include <net/ip.h> | |
136 | #include <net/protocol.h> | |
137 | #include <net/route.h> | |
138 | #include <linux/skbuff.h> | |
139 | #include <net/sock.h> | |
140 | #include <net/arp.h> | |
141 | #include <net/icmp.h> | |
142 | #include <net/raw.h> | |
143 | #include <net/checksum.h> | |
1f07d03e | 144 | #include <net/inet_ecn.h> |
1da177e4 LT |
145 | #include <linux/netfilter_ipv4.h> |
146 | #include <net/xfrm.h> | |
147 | #include <linux/mroute.h> | |
148 | #include <linux/netlink.h> | |
f38a9eb1 | 149 | #include <net/dst_metadata.h> |
1da177e4 | 150 | |
1da177e4 | 151 | /* |
66018506 | 152 | * Process Router Attention IP option (RFC 2113) |
e905a9ed | 153 | */ |
ba57b4db | 154 | bool ip_call_ra_chain(struct sk_buff *skb) |
1da177e4 LT |
155 | { |
156 | struct ip_ra_chain *ra; | |
eddc9ec5 | 157 | u8 protocol = ip_hdr(skb)->protocol; |
1da177e4 | 158 | struct sock *last = NULL; |
cb84663e | 159 | struct net_device *dev = skb->dev; |
37fcbab6 | 160 | struct net *net = dev_net(dev); |
1da177e4 | 161 | |
5796ef75 | 162 | for (ra = rcu_dereference(net->ipv4.ra_chain); ra; ra = rcu_dereference(ra->next)) { |
1da177e4 LT |
163 | struct sock *sk = ra->sk; |
164 | ||
165 | /* If socket is bound to an interface, only report | |
166 | * the packet if it came from that interface. | |
167 | */ | |
c720c7e8 | 168 | if (sk && inet_sk(sk)->inet_num == protocol && |
1da177e4 | 169 | (!sk->sk_bound_dev_if || |
5796ef75 | 170 | sk->sk_bound_dev_if == dev->ifindex)) { |
56f8a75c | 171 | if (ip_is_fragment(ip_hdr(skb))) { |
19bcf9f2 | 172 | if (ip_defrag(net, skb, IP_DEFRAG_CALL_RA_CHAIN)) |
ba57b4db | 173 | return true; |
1da177e4 LT |
174 | } |
175 | if (last) { | |
176 | struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); | |
177 | if (skb2) | |
178 | raw_rcv(last, skb2); | |
179 | } | |
180 | last = sk; | |
181 | } | |
182 | } | |
183 | ||
184 | if (last) { | |
185 | raw_rcv(last, skb); | |
ba57b4db | 186 | return true; |
1da177e4 | 187 | } |
ba57b4db | 188 | return false; |
1da177e4 LT |
189 | } |
190 | ||
0c4b51f0 | 191 | static int ip_local_deliver_finish(struct net *net, struct sock *sk, struct sk_buff *skb) |
1da177e4 | 192 | { |
21d1196a | 193 | __skb_pull(skb, skb_network_header_len(skb)); |
1da177e4 LT |
194 | |
195 | rcu_read_lock(); | |
196 | { | |
eddc9ec5 | 197 | int protocol = ip_hdr(skb)->protocol; |
32613090 | 198 | const struct net_protocol *ipprot; |
f9242b6b | 199 | int raw; |
1da177e4 LT |
200 | |
201 | resubmit: | |
7bc54c90 | 202 | raw = raw_local_deliver(skb, protocol); |
1da177e4 | 203 | |
f9242b6b | 204 | ipprot = rcu_dereference(inet_protos[protocol]); |
00db4124 | 205 | if (ipprot) { |
1da177e4 LT |
206 | int ret; |
207 | ||
b59c2701 PM |
208 | if (!ipprot->no_policy) { |
209 | if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { | |
210 | kfree_skb(skb); | |
211 | goto out; | |
212 | } | |
213 | nf_reset(skb); | |
1da177e4 LT |
214 | } |
215 | ret = ipprot->handler(skb); | |
216 | if (ret < 0) { | |
217 | protocol = -ret; | |
218 | goto resubmit; | |
219 | } | |
b45386ef | 220 | __IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); |
1da177e4 | 221 | } else { |
7bc54c90 | 222 | if (!raw) { |
1da177e4 | 223 | if (xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
b45386ef | 224 | __IP_INC_STATS(net, IPSTATS_MIB_INUNKNOWNPROTOS); |
1da177e4 LT |
225 | icmp_send(skb, ICMP_DEST_UNREACH, |
226 | ICMP_PROT_UNREACH, 0); | |
227 | } | |
d8c6f4b9 NH |
228 | kfree_skb(skb); |
229 | } else { | |
b45386ef | 230 | __IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); |
d8c6f4b9 NH |
231 | consume_skb(skb); |
232 | } | |
1da177e4 LT |
233 | } |
234 | } | |
235 | out: | |
236 | rcu_read_unlock(); | |
237 | ||
238 | return 0; | |
239 | } | |
240 | ||
241 | /* | |
242 | * Deliver IP Packets to the higher protocol layers. | |
e905a9ed | 243 | */ |
1da177e4 LT |
244 | int ip_local_deliver(struct sk_buff *skb) |
245 | { | |
246 | /* | |
247 | * Reassemble IP fragments. | |
248 | */ | |
19bcf9f2 | 249 | struct net *net = dev_net(skb->dev); |
1da177e4 | 250 | |
56f8a75c | 251 | if (ip_is_fragment(ip_hdr(skb))) { |
19bcf9f2 | 252 | if (ip_defrag(net, skb, IP_DEFRAG_LOCAL_DELIVER)) |
1da177e4 LT |
253 | return 0; |
254 | } | |
255 | ||
29a26a56 | 256 | return NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_IN, |
19bcf9f2 | 257 | net, NULL, skb, skb->dev, NULL, |
1da177e4 LT |
258 | ip_local_deliver_finish); |
259 | } | |
260 | ||
6a91395f | 261 | static inline bool ip_rcv_options(struct sk_buff *skb) |
d245407e TG |
262 | { |
263 | struct ip_options *opt; | |
b71d1d42 | 264 | const struct iphdr *iph; |
d245407e TG |
265 | struct net_device *dev = skb->dev; |
266 | ||
267 | /* It looks as overkill, because not all | |
268 | IP options require packet mangling. | |
269 | But it is the easiest for now, especially taking | |
270 | into account that combination of IP options | |
271 | and running sniffer is extremely rare condition. | |
272 | --ANK (980813) | |
273 | */ | |
274 | if (skb_cow(skb, skb_headroom(skb))) { | |
b45386ef | 275 | __IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INDISCARDS); |
d245407e TG |
276 | goto drop; |
277 | } | |
278 | ||
eddc9ec5 | 279 | iph = ip_hdr(skb); |
22aba383 DL |
280 | opt = &(IPCB(skb)->opt); |
281 | opt->optlen = iph->ihl*4 - sizeof(struct iphdr); | |
d245407e | 282 | |
c346dca1 | 283 | if (ip_options_compile(dev_net(dev), opt, skb)) { |
b45386ef | 284 | __IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INHDRERRORS); |
d245407e TG |
285 | goto drop; |
286 | } | |
287 | ||
d245407e | 288 | if (unlikely(opt->srr)) { |
6e8b11b4 ED |
289 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
290 | ||
d245407e TG |
291 | if (in_dev) { |
292 | if (!IN_DEV_SOURCE_ROUTE(in_dev)) { | |
e87cc472 JP |
293 | if (IN_DEV_LOG_MARTIANS(in_dev)) |
294 | net_info_ratelimited("source route option %pI4 -> %pI4\n", | |
295 | &iph->saddr, | |
296 | &iph->daddr); | |
d245407e TG |
297 | goto drop; |
298 | } | |
d245407e TG |
299 | } |
300 | ||
301 | if (ip_options_rcv_srr(skb)) | |
302 | goto drop; | |
303 | } | |
304 | ||
6a91395f | 305 | return false; |
d245407e | 306 | drop: |
6a91395f | 307 | return true; |
d245407e TG |
308 | } |
309 | ||
5fa12739 EC |
310 | static int ip_rcv_finish_core(struct net *net, struct sock *sk, |
311 | struct sk_buff *skb) | |
1da177e4 | 312 | { |
eddc9ec5 | 313 | const struct iphdr *iph = ip_hdr(skb); |
7487449c | 314 | int (*edemux)(struct sk_buff *skb); |
d6f64d72 | 315 | struct net_device *dev = skb->dev; |
7487449c PA |
316 | struct rtable *rt; |
317 | int err; | |
1da177e4 | 318 | |
e21145a9 | 319 | if (net->ipv4.sysctl_ip_early_demux && |
63e51b6a ED |
320 | !skb_dst(skb) && |
321 | !skb->sk && | |
322 | !ip_is_fragment(iph)) { | |
160eb5a6 DM |
323 | const struct net_protocol *ipprot; |
324 | int protocol = iph->protocol; | |
325 | ||
160eb5a6 | 326 | ipprot = rcu_dereference(inet_protos[protocol]); |
dddb64bc | 327 | if (ipprot && (edemux = READ_ONCE(ipprot->early_demux))) { |
7487449c PA |
328 | err = edemux(skb); |
329 | if (unlikely(err)) | |
330 | goto drop_error; | |
9cb429d6 ED |
331 | /* must reload iph, skb->head might have changed */ |
332 | iph = ip_hdr(skb); | |
333 | } | |
160eb5a6 DM |
334 | } |
335 | ||
1da177e4 LT |
336 | /* |
337 | * Initialise the virtual path cache for the packet. It describes | |
338 | * how the packet travels inside Linux networking. | |
e905a9ed | 339 | */ |
f38a9eb1 | 340 | if (!skb_valid_dst(skb)) { |
7487449c PA |
341 | err = ip_route_input_noref(skb, iph->daddr, iph->saddr, |
342 | iph->tos, dev); | |
343 | if (unlikely(err)) | |
344 | goto drop_error; | |
1da177e4 LT |
345 | } |
346 | ||
c7066f70 | 347 | #ifdef CONFIG_IP_ROUTE_CLASSID |
adf30907 | 348 | if (unlikely(skb_dst(skb)->tclassid)) { |
7a9b2d59 | 349 | struct ip_rt_acct *st = this_cpu_ptr(ip_rt_acct); |
adf30907 | 350 | u32 idx = skb_dst(skb)->tclassid; |
1da177e4 | 351 | st[idx&0xFF].o_packets++; |
fd3f8c4c | 352 | st[idx&0xFF].o_bytes += skb->len; |
1da177e4 | 353 | st[(idx>>16)&0xFF].i_packets++; |
fd3f8c4c | 354 | st[(idx>>16)&0xFF].i_bytes += skb->len; |
1da177e4 LT |
355 | } |
356 | #endif | |
357 | ||
d245407e TG |
358 | if (iph->ihl > 5 && ip_rcv_options(skb)) |
359 | goto drop; | |
1da177e4 | 360 | |
511c3f92 | 361 | rt = skb_rtable(skb); |
edf391ff | 362 | if (rt->rt_type == RTN_MULTICAST) { |
b15084ec | 363 | __IP_UPD_PO_STATS(net, IPSTATS_MIB_INMCAST, skb->len); |
12b74dfa | 364 | } else if (rt->rt_type == RTN_BROADCAST) { |
b15084ec | 365 | __IP_UPD_PO_STATS(net, IPSTATS_MIB_INBCAST, skb->len); |
12b74dfa JB |
366 | } else if (skb->pkt_type == PACKET_BROADCAST || |
367 | skb->pkt_type == PACKET_MULTICAST) { | |
d6f64d72 | 368 | struct in_device *in_dev = __in_dev_get_rcu(dev); |
12b74dfa JB |
369 | |
370 | /* RFC 1122 3.3.6: | |
371 | * | |
372 | * When a host sends a datagram to a link-layer broadcast | |
373 | * address, the IP destination address MUST be a legal IP | |
374 | * broadcast or IP multicast address. | |
375 | * | |
376 | * A host SHOULD silently discard a datagram that is received | |
377 | * via a link-layer broadcast (see Section 2.4) but does not | |
378 | * specify an IP multicast or broadcast destination address. | |
379 | * | |
380 | * This doesn't explicitly say L2 *broadcast*, but broadcast is | |
381 | * in a way a form of multicast and the most common use case for | |
382 | * this is 802.11 protecting against cross-station spoofing (the | |
383 | * so-called "hole-196" attack) so do it for both. | |
384 | */ | |
385 | if (in_dev && | |
386 | IN_DEV_ORCONF(in_dev, DROP_UNICAST_IN_L2_MULTICAST)) | |
387 | goto drop; | |
388 | } | |
5506b54b | 389 | |
5fa12739 | 390 | return NET_RX_SUCCESS; |
1da177e4 | 391 | |
1da177e4 | 392 | drop: |
e905a9ed YH |
393 | kfree_skb(skb); |
394 | return NET_RX_DROP; | |
7487449c PA |
395 | |
396 | drop_error: | |
397 | if (err == -EXDEV) | |
398 | __NET_INC_STATS(net, LINUX_MIB_IPRPFILTER); | |
399 | goto drop; | |
1da177e4 LT |
400 | } |
401 | ||
5fa12739 EC |
402 | static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) |
403 | { | |
efe6aaca EC |
404 | int ret; |
405 | ||
406 | /* if ingress device is enslaved to an L3 master device pass the | |
407 | * skb to its handler for processing | |
408 | */ | |
409 | skb = l3mdev_ip_rcv(skb); | |
410 | if (!skb) | |
411 | return NET_RX_SUCCESS; | |
5fa12739 | 412 | |
efe6aaca | 413 | ret = ip_rcv_finish_core(net, sk, skb); |
5fa12739 EC |
414 | if (ret != NET_RX_DROP) |
415 | ret = dst_input(skb); | |
416 | return ret; | |
417 | } | |
418 | ||
1da177e4 LT |
419 | /* |
420 | * Main IP Receive routine. | |
e905a9ed | 421 | */ |
17266ee9 | 422 | static struct sk_buff *ip_rcv_core(struct sk_buff *skb, struct net *net) |
1da177e4 | 423 | { |
b71d1d42 | 424 | const struct iphdr *iph; |
58615242 | 425 | u32 len; |
1da177e4 LT |
426 | |
427 | /* When the interface is in promisc. mode, drop all the crap | |
428 | * that it receives, do not try to analyse it. | |
429 | */ | |
430 | if (skb->pkt_type == PACKET_OTHERHOST) | |
431 | goto drop; | |
432 | ||
edf391ff | 433 | |
b15084ec | 434 | __IP_UPD_PO_STATS(net, IPSTATS_MIB_IN, skb->len); |
1da177e4 | 435 | |
51456b29 IM |
436 | skb = skb_share_check(skb, GFP_ATOMIC); |
437 | if (!skb) { | |
b45386ef | 438 | __IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); |
1da177e4 LT |
439 | goto out; |
440 | } | |
441 | ||
442 | if (!pskb_may_pull(skb, sizeof(struct iphdr))) | |
443 | goto inhdr_error; | |
444 | ||
eddc9ec5 | 445 | iph = ip_hdr(skb); |
1da177e4 LT |
446 | |
447 | /* | |
c67fa027 | 448 | * RFC1122: 3.2.1.2 MUST silently discard any IP frame that fails the checksum. |
1da177e4 LT |
449 | * |
450 | * Is the datagram acceptable? | |
451 | * | |
452 | * 1. Length at least the size of an ip header | |
453 | * 2. Version of 4 | |
454 | * 3. Checksums correctly. [Speed optimisation for later, skip loopback checksums] | |
455 | * 4. Doesn't have a bogus length | |
456 | */ | |
457 | ||
458 | if (iph->ihl < 5 || iph->version != 4) | |
58615242 | 459 | goto inhdr_error; |
1da177e4 | 460 | |
1f07d03e ED |
461 | BUILD_BUG_ON(IPSTATS_MIB_ECT1PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_1); |
462 | BUILD_BUG_ON(IPSTATS_MIB_ECT0PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_0); | |
463 | BUILD_BUG_ON(IPSTATS_MIB_CEPKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_CE); | |
98f61995 ED |
464 | __IP_ADD_STATS(net, |
465 | IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), | |
466 | max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); | |
1f07d03e | 467 | |
1da177e4 LT |
468 | if (!pskb_may_pull(skb, iph->ihl*4)) |
469 | goto inhdr_error; | |
470 | ||
eddc9ec5 | 471 | iph = ip_hdr(skb); |
1da177e4 | 472 | |
e9c60422 | 473 | if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) |
6a5dc9e5 | 474 | goto csum_error; |
1da177e4 | 475 | |
58615242 | 476 | len = ntohs(iph->tot_len); |
704aed53 | 477 | if (skb->len < len) { |
b45386ef | 478 | __IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); |
704aed53 MC |
479 | goto drop; |
480 | } else if (len < (iph->ihl*4)) | |
58615242 | 481 | goto inhdr_error; |
1da177e4 | 482 | |
58615242 TG |
483 | /* Our transport medium may have padded the buffer out. Now we know it |
484 | * is IP we can trim to the true length of the frame. | |
485 | * Note this now means skb->len holds ntohs(iph->tot_len). | |
486 | */ | |
487 | if (pskb_trim_rcsum(skb, len)) { | |
b45386ef | 488 | __IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); |
58615242 | 489 | goto drop; |
1da177e4 LT |
490 | } |
491 | ||
21d1196a ED |
492 | skb->transport_header = skb->network_header + iph->ihl*4; |
493 | ||
53602f92 | 494 | /* Remove any debris in the socket control block */ |
d569f1d7 | 495 | memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); |
0b922b7a | 496 | IPCB(skb)->iif = skb->skb_iif; |
53602f92 | 497 | |
71f9dacd HX |
498 | /* Must drop socket now because of tproxy. */ |
499 | skb_orphan(skb); | |
500 | ||
17266ee9 | 501 | return skb; |
1da177e4 | 502 | |
6a5dc9e5 | 503 | csum_error: |
b45386ef | 504 | __IP_INC_STATS(net, IPSTATS_MIB_CSUMERRORS); |
1da177e4 | 505 | inhdr_error: |
b45386ef | 506 | __IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS); |
1da177e4 | 507 | drop: |
e905a9ed | 508 | kfree_skb(skb); |
1da177e4 | 509 | out: |
17266ee9 EC |
510 | return NULL; |
511 | } | |
512 | ||
513 | /* | |
514 | * IP receive entry point | |
515 | */ | |
516 | int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, | |
517 | struct net_device *orig_dev) | |
518 | { | |
519 | struct net *net = dev_net(dev); | |
520 | ||
521 | skb = ip_rcv_core(skb, net); | |
522 | if (skb == NULL) | |
523 | return NET_RX_DROP; | |
524 | return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, | |
525 | net, NULL, skb, dev, NULL, | |
526 | ip_rcv_finish); | |
527 | } | |
528 | ||
5fa12739 | 529 | static void ip_sublist_rcv_finish(struct list_head *head) |
17266ee9 EC |
530 | { |
531 | struct sk_buff *skb, *next; | |
532 | ||
0761680d JDB |
533 | list_for_each_entry_safe(skb, next, head, list) { |
534 | list_del(&skb->list); | |
535 | /* Handle ip{6}_forward case, as sch_direct_xmit have | |
536 | * another kind of SKB-list usage (see validate_xmit_skb_list) | |
537 | */ | |
538 | skb->next = NULL; | |
5fa12739 | 539 | dst_input(skb); |
0761680d | 540 | } |
5fa12739 EC |
541 | } |
542 | ||
543 | static void ip_list_rcv_finish(struct net *net, struct sock *sk, | |
544 | struct list_head *head) | |
545 | { | |
546 | struct dst_entry *curr_dst = NULL; | |
547 | struct sk_buff *skb, *next; | |
548 | struct list_head sublist; | |
549 | ||
a4ca8b7d | 550 | INIT_LIST_HEAD(&sublist); |
5fa12739 EC |
551 | list_for_each_entry_safe(skb, next, head, list) { |
552 | struct dst_entry *dst; | |
553 | ||
a4ca8b7d | 554 | list_del(&skb->list); |
efe6aaca EC |
555 | /* if ingress device is enslaved to an L3 master device pass the |
556 | * skb to its handler for processing | |
557 | */ | |
558 | skb = l3mdev_ip_rcv(skb); | |
559 | if (!skb) | |
560 | continue; | |
5fa12739 EC |
561 | if (ip_rcv_finish_core(net, sk, skb) == NET_RX_DROP) |
562 | continue; | |
563 | ||
564 | dst = skb_dst(skb); | |
565 | if (curr_dst != dst) { | |
566 | /* dispatch old sublist */ | |
5fa12739 EC |
567 | if (!list_empty(&sublist)) |
568 | ip_sublist_rcv_finish(&sublist); | |
569 | /* start new sublist */ | |
a4ca8b7d | 570 | INIT_LIST_HEAD(&sublist); |
5fa12739 EC |
571 | curr_dst = dst; |
572 | } | |
a4ca8b7d | 573 | list_add_tail(&skb->list, &sublist); |
5fa12739 EC |
574 | } |
575 | /* dispatch final sublist */ | |
a4ca8b7d | 576 | ip_sublist_rcv_finish(&sublist); |
5fa12739 EC |
577 | } |
578 | ||
579 | static void ip_sublist_rcv(struct list_head *head, struct net_device *dev, | |
580 | struct net *net) | |
581 | { | |
17266ee9 EC |
582 | NF_HOOK_LIST(NFPROTO_IPV4, NF_INET_PRE_ROUTING, net, NULL, |
583 | head, dev, NULL, ip_rcv_finish); | |
5fa12739 | 584 | ip_list_rcv_finish(net, NULL, head); |
17266ee9 EC |
585 | } |
586 | ||
587 | /* Receive a list of IP packets */ | |
588 | void ip_list_rcv(struct list_head *head, struct packet_type *pt, | |
589 | struct net_device *orig_dev) | |
590 | { | |
591 | struct net_device *curr_dev = NULL; | |
592 | struct net *curr_net = NULL; | |
593 | struct sk_buff *skb, *next; | |
594 | struct list_head sublist; | |
595 | ||
a4ca8b7d | 596 | INIT_LIST_HEAD(&sublist); |
17266ee9 EC |
597 | list_for_each_entry_safe(skb, next, head, list) { |
598 | struct net_device *dev = skb->dev; | |
599 | struct net *net = dev_net(dev); | |
600 | ||
a4ca8b7d | 601 | list_del(&skb->list); |
17266ee9 EC |
602 | skb = ip_rcv_core(skb, net); |
603 | if (skb == NULL) | |
604 | continue; | |
605 | ||
606 | if (curr_dev != dev || curr_net != net) { | |
607 | /* dispatch old sublist */ | |
17266ee9 | 608 | if (!list_empty(&sublist)) |
a4ca8b7d | 609 | ip_sublist_rcv(&sublist, curr_dev, curr_net); |
17266ee9 | 610 | /* start new sublist */ |
a4ca8b7d | 611 | INIT_LIST_HEAD(&sublist); |
17266ee9 EC |
612 | curr_dev = dev; |
613 | curr_net = net; | |
614 | } | |
a4ca8b7d | 615 | list_add_tail(&skb->list, &sublist); |
17266ee9 EC |
616 | } |
617 | /* dispatch final sublist */ | |
a4ca8b7d | 618 | ip_sublist_rcv(&sublist, curr_dev, curr_net); |
1da177e4 | 619 | } |