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net/ipv4/ip_input.c
14.7 KB
1da177e4c Linux-2.6.12-rc2 |
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/* * INET An implementation of the TCP/IP protocol suite for the LINUX * operating system. INET is implemented using the BSD Socket * interface as the means of communication with the user level. * * The Internet Protocol (IP) module. * |
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* Authors: Ross Biro |
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> * Donald Becker, <becker@super.org> |
113aa838e net: Rationalise ... |
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* Alan Cox, <alan@lxorguk.ukuu.org.uk> |
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* Richard Underwood * Stefan Becker, <stefanb@yello.ping.de> * Jorge Cwik, <jorge@laser.satlink.net> * Arnt Gulbrandsen, <agulbra@nvg.unit.no> |
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* |
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* * Fixes: * Alan Cox : Commented a couple of minor bits of surplus code * Alan Cox : Undefining IP_FORWARD doesn't include the code * (just stops a compiler warning). * Alan Cox : Frames with >=MAX_ROUTE record routes, strict routes or loose routes * are junked rather than corrupting things. * Alan Cox : Frames to bad broadcast subnets are dumped * We used to process them non broadcast and * boy could that cause havoc. * Alan Cox : ip_forward sets the free flag on the * new frame it queues. Still crap because * it copies the frame but at least it * doesn't eat memory too. * Alan Cox : Generic queue code and memory fixes. * Fred Van Kempen : IP fragment support (borrowed from NET2E) * Gerhard Koerting: Forward fragmented frames correctly. * Gerhard Koerting: Fixes to my fix of the above 8-). * Gerhard Koerting: IP interface addressing fix. * Linus Torvalds : More robustness checks * Alan Cox : Even more checks: Still not as robust as it ought to be * Alan Cox : Save IP header pointer for later * Alan Cox : ip option setting * Alan Cox : Use ip_tos/ip_ttl settings * Alan Cox : Fragmentation bogosity removed * (Thanks to Mark.Bush@prg.ox.ac.uk) * Dmitry Gorodchanin : Send of a raw packet crash fix. * Alan Cox : Silly ip bug when an overlength * fragment turns up. Now frees the * queue. * Linus Torvalds/ : Memory leakage on fragmentation * Alan Cox : handling. * Gerhard Koerting: Forwarding uses IP priority hints * Teemu Rantanen : Fragment problems. * Alan Cox : General cleanup, comments and reformat * Alan Cox : SNMP statistics * Alan Cox : BSD address rule semantics. Also see * UDP as there is a nasty checksum issue * if you do things the wrong way. * Alan Cox : Always defrag, moved IP_FORWARD to the config.in file * Alan Cox : IP options adjust sk->priority. * Pedro Roque : Fix mtu/length error in ip_forward. * Alan Cox : Avoid ip_chk_addr when possible. * Richard Underwood : IP multicasting. * Alan Cox : Cleaned up multicast handlers. * Alan Cox : RAW sockets demultiplex in the BSD style. * Gunther Mayer : Fix the SNMP reporting typo * Alan Cox : Always in group 224.0.0.1 * Pauline Middelink : Fast ip_checksum update when forwarding * Masquerading support. * Alan Cox : Multicast loopback error for 224.0.0.1 * Alan Cox : IP_MULTICAST_LOOP option. * Alan Cox : Use notifiers. * Bjorn Ekwall : Removed ip_csum (from slhc.c too) * Bjorn Ekwall : Moved ip_fast_csum to ip.h (inline!) * Stefan Becker : Send out ICMP HOST REDIRECT * Arnt Gulbrandsen : ip_build_xmit * Alan Cox : Per socket routing cache * Alan Cox : Fixed routing cache, added header cache. * Alan Cox : Loopback didn't work right in original ip_build_xmit - fixed it. * Alan Cox : Only send ICMP_REDIRECT if src/dest are the same net. * Alan Cox : Incoming IP option handling. * Alan Cox : Set saddr on raw output frames as per BSD. * Alan Cox : Stopped broadcast source route explosions. * Alan Cox : Can disable source routing * Takeshi Sone : Masquerading didn't work. * Dave Bonn,Alan Cox : Faster IP forwarding whenever possible. * Alan Cox : Memory leaks, tramples, misc debugging. * Alan Cox : Fixed multicast (by popular demand 8)) * Alan Cox : Fixed forwarding (by even more popular demand 8)) * Alan Cox : Fixed SNMP statistics [I think] * Gerhard Koerting : IP fragmentation forwarding fix * Alan Cox : Device lock against page fault. * Alan Cox : IP_HDRINCL facility. * Werner Almesberger : Zero fragment bug * Alan Cox : RAW IP frame length bug * Alan Cox : Outgoing firewall on build_xmit * A.N.Kuznetsov : IP_OPTIONS support throughout the kernel * Alan Cox : Multicast routing hooks * Jos Vos : Do accounting *before* call_in_firewall * Willy Konynenberg : Transparent proxying support * |
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* |
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* * To Fix: * IP fragmentation wants rewriting cleanly. The RFC815 algorithm is much more efficient * and could be made very efficient with the addition of some virtual memory hacks to permit * the allocation of a buffer that can then be 'grown' by twiddling page tables. |
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* Output fragmentation wants updating along with the buffer management to use a single |
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* interleaved copy algorithm so that fragmenting has a one copy overhead. Actual packet * output should probably do its own fragmentation at the UDP/RAW layer. TCP shouldn't cause * fragmentation anyway. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ |
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#define pr_fmt(fmt) "IPv4: " fmt |
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#include <linux/module.h> #include <linux/types.h> #include <linux/kernel.h> #include <linux/string.h> #include <linux/errno.h> |
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#include <linux/slab.h> |
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#include <linux/net.h> #include <linux/socket.h> #include <linux/sockios.h> #include <linux/in.h> #include <linux/inet.h> |
14c850212 [INET_SOCK]: Move... |
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#include <linux/inetdevice.h> |
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#include <linux/netdevice.h> #include <linux/etherdevice.h> #include <net/snmp.h> #include <net/ip.h> #include <net/protocol.h> #include <net/route.h> #include <linux/skbuff.h> #include <net/sock.h> #include <net/arp.h> #include <net/icmp.h> #include <net/raw.h> #include <net/checksum.h> |
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#include <net/inet_ecn.h> |
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#include <linux/netfilter_ipv4.h> #include <net/xfrm.h> #include <linux/mroute.h> #include <linux/netlink.h> |
f38a9eb1f dst: Metadata des... |
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#include <net/dst_metadata.h> |
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/* |
66018506e ip: Router Alert ... |
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* Process Router Attention IP option (RFC 2113) |
e905a9eda [NET] IPV4: Fix w... |
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*/ |
ba57b4db2 ipv4: Make ip_cal... |
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bool ip_call_ra_chain(struct sk_buff *skb) |
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{ struct ip_ra_chain *ra; |
eddc9ec53 [SK_BUFF]: Introd... |
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u8 protocol = ip_hdr(skb)->protocol; |
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struct sock *last = NULL; |
cb84663e4 [NETNS]: Process ... |
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struct net_device *dev = skb->dev; |
37fcbab61 ipv4: Only comput... |
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struct net *net = dev_net(dev); |
1da177e4c Linux-2.6.12-rc2 |
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|
66018506e ip: Router Alert ... |
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for (ra = rcu_dereference(ip_ra_chain); ra; ra = rcu_dereference(ra->next)) { |
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struct sock *sk = ra->sk; /* If socket is bound to an interface, only report * the packet if it came from that interface. */ |
c720c7e83 inet: rename some... |
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if (sk && inet_sk(sk)->inet_num == protocol && |
1da177e4c Linux-2.6.12-rc2 |
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(!sk->sk_bound_dev_if || |
cb84663e4 [NETNS]: Process ... |
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sk->sk_bound_dev_if == dev->ifindex) && |
37fcbab61 ipv4: Only comput... |
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net_eq(sock_net(sk), net)) { |
56f8a75c1 ip: introduce ip_... |
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if (ip_is_fragment(ip_hdr(skb))) { |
19bcf9f20 ipv4: Pass struct... |
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if (ip_defrag(net, skb, IP_DEFRAG_CALL_RA_CHAIN)) |
ba57b4db2 ipv4: Make ip_cal... |
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return true; |
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} if (last) { struct sk_buff *skb2 = skb_clone(skb, GFP_ATOMIC); if (skb2) raw_rcv(last, skb2); } last = sk; } } if (last) { raw_rcv(last, skb); |
ba57b4db2 ipv4: Make ip_cal... |
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return true; |
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} |
ba57b4db2 ipv4: Make ip_cal... |
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return false; |
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} |
0c4b51f00 netfilter: Pass n... |
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static int ip_local_deliver_finish(struct net *net, struct sock *sk, struct sk_buff *skb) |
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{ |
21d1196a3 ipv4: set transpo... |
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__skb_pull(skb, skb_network_header_len(skb)); |
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rcu_read_lock(); { |
eddc9ec53 [SK_BUFF]: Introd... |
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int protocol = ip_hdr(skb)->protocol; |
32613090a net: constify str... |
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const struct net_protocol *ipprot; |
f9242b6b2 inet: Sanitize in... |
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int raw; |
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resubmit: |
7bc54c903 [IPv4] RAW: Compa... |
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raw = raw_local_deliver(skb, protocol); |
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|
f9242b6b2 inet: Sanitize in... |
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ipprot = rcu_dereference(inet_protos[protocol]); |
00db41243 ipv4: coding styl... |
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if (ipprot) { |
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int ret; |
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if (!ipprot->no_policy) { if (!xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { kfree_skb(skb); goto out; } nf_reset(skb); |
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} ret = ipprot->handler(skb); if (ret < 0) { protocol = -ret; goto resubmit; } |
b45386efa net: rename IP_IN... |
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__IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); |
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} else { |
7bc54c903 [IPv4] RAW: Compa... |
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if (!raw) { |
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if (xfrm4_policy_check(NULL, XFRM_POLICY_IN, skb)) { |
b45386efa net: rename IP_IN... |
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__IP_INC_STATS(net, IPSTATS_MIB_INUNKNOWNPROTOS); |
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icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PROT_UNREACH, 0); } |
d8c6f4b9b ipv[4|6]: correct... |
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kfree_skb(skb); } else { |
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__IP_INC_STATS(net, IPSTATS_MIB_INDELIVERS); |
d8c6f4b9b ipv[4|6]: correct... |
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consume_skb(skb); } |
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} } out: rcu_read_unlock(); return 0; } /* * Deliver IP Packets to the higher protocol layers. |
e905a9eda [NET] IPV4: Fix w... |
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*/ |
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int ip_local_deliver(struct sk_buff *skb) { /* * Reassemble IP fragments. */ |
19bcf9f20 ipv4: Pass struct... |
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struct net *net = dev_net(skb->dev); |
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|
56f8a75c1 ip: introduce ip_... |
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if (ip_is_fragment(ip_hdr(skb))) { |
19bcf9f20 ipv4: Pass struct... |
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if (ip_defrag(net, skb, IP_DEFRAG_LOCAL_DELIVER)) |
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return 0; } |
29a26a568 netfilter: Pass s... |
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return NF_HOOK(NFPROTO_IPV4, NF_INET_LOCAL_IN, |
19bcf9f20 ipv4: Pass struct... |
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net, NULL, skb, skb->dev, NULL, |
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ip_local_deliver_finish); } |
6a91395f2 ipv4: Make ip_rcv... |
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static inline bool ip_rcv_options(struct sk_buff *skb) |
d245407e7 [IPV4]: Move ip o... |
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{ struct ip_options *opt; |
b71d1d426 inet: constify ip... |
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const struct iphdr *iph; |
d245407e7 [IPV4]: Move ip o... |
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struct net_device *dev = skb->dev; /* It looks as overkill, because not all IP options require packet mangling. But it is the easiest for now, especially taking into account that combination of IP options and running sniffer is extremely rare condition. --ANK (980813) */ if (skb_cow(skb, skb_headroom(skb))) { |
b45386efa net: rename IP_IN... |
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__IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INDISCARDS); |
d245407e7 [IPV4]: Move ip o... |
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goto drop; } |
eddc9ec53 [SK_BUFF]: Introd... |
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iph = ip_hdr(skb); |
22aba383c [IPV4]: Always pa... |
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opt = &(IPCB(skb)->opt); opt->optlen = iph->ihl*4 - sizeof(struct iphdr); |
d245407e7 [IPV4]: Move ip o... |
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|
c346dca10 [NET] NETNS: Omit... |
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if (ip_options_compile(dev_net(dev), opt, skb)) { |
b45386efa net: rename IP_IN... |
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__IP_INC_STATS(dev_net(dev), IPSTATS_MIB_INHDRERRORS); |
d245407e7 [IPV4]: Move ip o... |
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goto drop; } |
d245407e7 [IPV4]: Move ip o... |
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if (unlikely(opt->srr)) { |
6e8b11b43 net: avoid two at... |
282 |
struct in_device *in_dev = __in_dev_get_rcu(dev); |
d245407e7 [IPV4]: Move ip o... |
283 284 |
if (in_dev) { if (!IN_DEV_SOURCE_ROUTE(in_dev)) { |
e87cc4728 net: Convert net_... |
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if (IN_DEV_LOG_MARTIANS(in_dev)) net_info_ratelimited("source route option %pI4 -> %pI4 ", &iph->saddr, &iph->daddr); |
d245407e7 [IPV4]: Move ip o... |
290 291 |
goto drop; } |
d245407e7 [IPV4]: Move ip o... |
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} if (ip_options_rcv_srr(skb)) goto drop; } |
6a91395f2 ipv4: Make ip_rcv... |
297 |
return false; |
d245407e7 [IPV4]: Move ip o... |
298 |
drop: |
6a91395f2 ipv4: Make ip_rcv... |
299 |
return true; |
d245407e7 [IPV4]: Move ip o... |
300 |
} |
0c4b51f00 netfilter: Pass n... |
301 |
static int ip_rcv_finish(struct net *net, struct sock *sk, struct sk_buff *skb) |
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{ |
eddc9ec53 [SK_BUFF]: Introd... |
303 |
const struct iphdr *iph = ip_hdr(skb); |
7487449c8 IPv4: early demux... |
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int (*edemux)(struct sk_buff *skb); |
d6f64d725 net: VRF: Pass or... |
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struct net_device *dev = skb->dev; |
7487449c8 IPv4: early demux... |
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struct rtable *rt; int err; |
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|
74b20582a net: l3mdev: Add ... |
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/* if ingress device is enslaved to an L3 master device pass the * skb to its handler for processing */ skb = l3mdev_ip_rcv(skb); if (!skb) return NET_RX_SUCCESS; |
e21145a98 ipv4: namespacify... |
315 |
if (net->ipv4.sysctl_ip_early_demux && |
63e51b6a2 ipv4: early demux... |
316 317 318 |
!skb_dst(skb) && !skb->sk && !ip_is_fragment(iph)) { |
160eb5a6b ipv4: Kill early ... |
319 320 |
const struct net_protocol *ipprot; int protocol = iph->protocol; |
160eb5a6b ipv4: Kill early ... |
321 |
ipprot = rcu_dereference(inet_protos[protocol]); |
dddb64bcb net: Add sysctl t... |
322 |
if (ipprot && (edemux = READ_ONCE(ipprot->early_demux))) { |
7487449c8 IPv4: early demux... |
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err = edemux(skb); if (unlikely(err)) goto drop_error; |
9cb429d69 tcp: early_demux ... |
326 327 328 |
/* must reload iph, skb->head might have changed */ iph = ip_hdr(skb); } |
160eb5a6b ipv4: Kill early ... |
329 |
} |
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/* * Initialise the virtual path cache for the packet. It describes * how the packet travels inside Linux networking. |
e905a9eda [NET] IPV4: Fix w... |
333 |
*/ |
f38a9eb1f dst: Metadata des... |
334 |
if (!skb_valid_dst(skb)) { |
7487449c8 IPv4: early demux... |
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err = ip_route_input_noref(skb, iph->daddr, iph->saddr, iph->tos, dev); if (unlikely(err)) goto drop_error; |
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339 |
} |
c7066f70d netfilter: fix Kc... |
340 |
#ifdef CONFIG_IP_ROUTE_CLASSID |
adf30907d net: skb->dst acc... |
341 |
if (unlikely(skb_dst(skb)->tclassid)) { |
7a9b2d595 net: use this_cpu... |
342 |
struct ip_rt_acct *st = this_cpu_ptr(ip_rt_acct); |
adf30907d net: skb->dst acc... |
343 |
u32 idx = skb_dst(skb)->tclassid; |
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st[idx&0xFF].o_packets++; |
fd3f8c4cb net: clean up net... |
345 |
st[idx&0xFF].o_bytes += skb->len; |
1da177e4c Linux-2.6.12-rc2 |
346 |
st[(idx>>16)&0xFF].i_packets++; |
fd3f8c4cb net: clean up net... |
347 |
st[(idx>>16)&0xFF].i_bytes += skb->len; |
1da177e4c Linux-2.6.12-rc2 |
348 349 |
} #endif |
d245407e7 [IPV4]: Move ip o... |
350 351 |
if (iph->ihl > 5 && ip_rcv_options(skb)) goto drop; |
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352 |
|
511c3f92a net: skb->rtable ... |
353 |
rt = skb_rtable(skb); |
edf391ff1 snmp: add missing... |
354 |
if (rt->rt_type == RTN_MULTICAST) { |
b15084ec7 net: rename IP_UP... |
355 |
__IP_UPD_PO_STATS(net, IPSTATS_MIB_INMCAST, skb->len); |
12b74dfad ipv4: add option ... |
356 |
} else if (rt->rt_type == RTN_BROADCAST) { |
b15084ec7 net: rename IP_UP... |
357 |
__IP_UPD_PO_STATS(net, IPSTATS_MIB_INBCAST, skb->len); |
12b74dfad ipv4: add option ... |
358 359 |
} else if (skb->pkt_type == PACKET_BROADCAST || skb->pkt_type == PACKET_MULTICAST) { |
d6f64d725 net: VRF: Pass or... |
360 |
struct in_device *in_dev = __in_dev_get_rcu(dev); |
12b74dfad ipv4: add option ... |
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/* RFC 1122 3.3.6: * * When a host sends a datagram to a link-layer broadcast * address, the IP destination address MUST be a legal IP * broadcast or IP multicast address. * * A host SHOULD silently discard a datagram that is received * via a link-layer broadcast (see Section 2.4) but does not * specify an IP multicast or broadcast destination address. * * This doesn't explicitly say L2 *broadcast*, but broadcast is * in a way a form of multicast and the most common use case for * this is 802.11 protecting against cross-station spoofing (the * so-called "hole-196" attack) so do it for both. */ if (in_dev && IN_DEV_ORCONF(in_dev, DROP_UNICAST_IN_L2_MULTICAST)) goto drop; } |
5506b54b3 [IPV4] SNMP: Supp... |
381 |
|
1da177e4c Linux-2.6.12-rc2 |
382 |
return dst_input(skb); |
1da177e4c Linux-2.6.12-rc2 |
383 |
drop: |
e905a9eda [NET] IPV4: Fix w... |
384 385 |
kfree_skb(skb); return NET_RX_DROP; |
7487449c8 IPv4: early demux... |
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drop_error: if (err == -EXDEV) __NET_INC_STATS(net, LINUX_MIB_IPRPFILTER); goto drop; |
1da177e4c Linux-2.6.12-rc2 |
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} /* * Main IP Receive routine. |
e905a9eda [NET] IPV4: Fix w... |
395 |
*/ |
f2ccd8fa0 [NET]: Kill skb->... |
396 |
int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) |
1da177e4c Linux-2.6.12-rc2 |
397 |
{ |
b71d1d426 inet: constify ip... |
398 |
const struct iphdr *iph; |
e707766ce ipv4: Compute net... |
399 |
struct net *net; |
586152424 [IPV4]: Consisten... |
400 |
u32 len; |
1da177e4c Linux-2.6.12-rc2 |
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/* When the interface is in promisc. mode, drop all the crap * that it receives, do not try to analyse it. */ if (skb->pkt_type == PACKET_OTHERHOST) goto drop; |
edf391ff1 snmp: add missing... |
407 |
|
e707766ce ipv4: Compute net... |
408 |
net = dev_net(dev); |
b15084ec7 net: rename IP_UP... |
409 |
__IP_UPD_PO_STATS(net, IPSTATS_MIB_IN, skb->len); |
1da177e4c Linux-2.6.12-rc2 |
410 |
|
51456b291 ipv4: coding styl... |
411 412 |
skb = skb_share_check(skb, GFP_ATOMIC); if (!skb) { |
b45386efa net: rename IP_IN... |
413 |
__IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); |
1da177e4c Linux-2.6.12-rc2 |
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goto out; } if (!pskb_may_pull(skb, sizeof(struct iphdr))) goto inhdr_error; |
eddc9ec53 [SK_BUFF]: Introd... |
419 |
iph = ip_hdr(skb); |
1da177e4c Linux-2.6.12-rc2 |
420 421 |
/* |
c67fa0279 net/ipv4: correct... |
422 |
* RFC1122: 3.2.1.2 MUST silently discard any IP frame that fails the checksum. |
1da177e4c Linux-2.6.12-rc2 |
423 424 425 426 427 428 429 430 431 432 |
* * Is the datagram acceptable? * * 1. Length at least the size of an ip header * 2. Version of 4 * 3. Checksums correctly. [Speed optimisation for later, skip loopback checksums] * 4. Doesn't have a bogus length */ if (iph->ihl < 5 || iph->version != 4) |
586152424 [IPV4]: Consisten... |
433 |
goto inhdr_error; |
1da177e4c Linux-2.6.12-rc2 |
434 |
|
1f07d03e2 net: add SNMP cou... |
435 436 437 |
BUILD_BUG_ON(IPSTATS_MIB_ECT1PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_1); BUILD_BUG_ON(IPSTATS_MIB_ECT0PKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_ECT_0); BUILD_BUG_ON(IPSTATS_MIB_CEPKTS != IPSTATS_MIB_NOECTPKTS + INET_ECN_CE); |
98f619957 net: rename IP_AD... |
438 439 440 |
__IP_ADD_STATS(net, IPSTATS_MIB_NOECTPKTS + (iph->tos & INET_ECN_MASK), max_t(unsigned short, 1, skb_shinfo(skb)->gso_segs)); |
1f07d03e2 net: add SNMP cou... |
441 |
|
1da177e4c Linux-2.6.12-rc2 |
442 443 |
if (!pskb_may_pull(skb, iph->ihl*4)) goto inhdr_error; |
eddc9ec53 [SK_BUFF]: Introd... |
444 |
iph = ip_hdr(skb); |
1da177e4c Linux-2.6.12-rc2 |
445 |
|
e9c604227 [IPV4]: Avoid com... |
446 |
if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl))) |
6a5dc9e59 net: Add MIB coun... |
447 |
goto csum_error; |
1da177e4c Linux-2.6.12-rc2 |
448 |
|
586152424 [IPV4]: Consisten... |
449 |
len = ntohs(iph->tot_len); |
704aed53b [IPV4] SNMP: Supp... |
450 |
if (skb->len < len) { |
b45386efa net: rename IP_IN... |
451 |
__IP_INC_STATS(net, IPSTATS_MIB_INTRUNCATEDPKTS); |
704aed53b [IPV4] SNMP: Supp... |
452 453 |
goto drop; } else if (len < (iph->ihl*4)) |
586152424 [IPV4]: Consisten... |
454 |
goto inhdr_error; |
1da177e4c Linux-2.6.12-rc2 |
455 |
|
586152424 [IPV4]: Consisten... |
456 457 458 459 460 |
/* Our transport medium may have padded the buffer out. Now we know it * is IP we can trim to the true length of the frame. * Note this now means skb->len holds ntohs(iph->tot_len). */ if (pskb_trim_rcsum(skb, len)) { |
b45386efa net: rename IP_IN... |
461 |
__IP_INC_STATS(net, IPSTATS_MIB_INDISCARDS); |
586152424 [IPV4]: Consisten... |
462 |
goto drop; |
1da177e4c Linux-2.6.12-rc2 |
463 |
} |
66a011d15 net: Fix usage of... |
464 |
iph = ip_hdr(skb); |
21d1196a3 ipv4: set transpo... |
465 |
skb->transport_header = skb->network_header + iph->ihl*4; |
53602f92d [IPV4]: Clear skb... |
466 |
/* Remove any debris in the socket control block */ |
d569f1d72 [IPV4]: Clear the... |
467 |
memset(IPCB(skb), 0, sizeof(struct inet_skb_parm)); |
0b922b7a8 net: original ing... |
468 |
IPCB(skb)->iif = skb->skb_iif; |
53602f92d [IPV4]: Clear skb... |
469 |
|
71f9dacd2 inet: Call skb_or... |
470 471 |
/* Must drop socket now because of tproxy. */ skb_orphan(skb); |
29a26a568 netfilter: Pass s... |
472 473 |
return NF_HOOK(NFPROTO_IPV4, NF_INET_PRE_ROUTING, net, NULL, skb, dev, NULL, |
1da177e4c Linux-2.6.12-rc2 |
474 |
ip_rcv_finish); |
6a5dc9e59 net: Add MIB coun... |
475 |
csum_error: |
b45386efa net: rename IP_IN... |
476 |
__IP_INC_STATS(net, IPSTATS_MIB_CSUMERRORS); |
1da177e4c Linux-2.6.12-rc2 |
477 |
inhdr_error: |
b45386efa net: rename IP_IN... |
478 |
__IP_INC_STATS(net, IPSTATS_MIB_INHDRERRORS); |
1da177e4c Linux-2.6.12-rc2 |
479 |
drop: |
e905a9eda [NET] IPV4: Fix w... |
480 |
kfree_skb(skb); |
1da177e4c Linux-2.6.12-rc2 |
481 |
out: |
e905a9eda [NET] IPV4: Fix w... |
482 |
return NET_RX_DROP; |
1da177e4c Linux-2.6.12-rc2 |
483 |
} |