![Eric Dumazet](/assets/img/avatar_default.png)
Commit 0dbaee3b37
(net: Abstract default ADVMSS behind an
accessor.) introduced a possible crash in tcp_connect_init(), when
dst->default_advmss() is called from dst_metric_advmss()
Reported-by: George Spelvin <linux@horizon.com>
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
3347 lines
82 KiB
C
3347 lines
82 KiB
C
/*
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* INET An implementation of the TCP/IP protocol suite for the LINUX
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* operating system. INET is implemented using the BSD Socket
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* interface as the means of communication with the user level.
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*
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* ROUTE - implementation of the IP router.
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*
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* Authors: Ross Biro
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* Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
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* Alan Cox, <gw4pts@gw4pts.ampr.org>
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* Linus Torvalds, <Linus.Torvalds@helsinki.fi>
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* Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
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*
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* Fixes:
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* Alan Cox : Verify area fixes.
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* Alan Cox : cli() protects routing changes
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* Rui Oliveira : ICMP routing table updates
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* (rco@di.uminho.pt) Routing table insertion and update
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* Linus Torvalds : Rewrote bits to be sensible
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* Alan Cox : Added BSD route gw semantics
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* Alan Cox : Super /proc >4K
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* Alan Cox : MTU in route table
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* Alan Cox : MSS actually. Also added the window
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* clamper.
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* Sam Lantinga : Fixed route matching in rt_del()
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* Alan Cox : Routing cache support.
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* Alan Cox : Removed compatibility cruft.
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* Alan Cox : RTF_REJECT support.
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* Alan Cox : TCP irtt support.
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* Jonathan Naylor : Added Metric support.
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* Miquel van Smoorenburg : BSD API fixes.
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* Miquel van Smoorenburg : Metrics.
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* Alan Cox : Use __u32 properly
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* Alan Cox : Aligned routing errors more closely with BSD
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* our system is still very different.
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* Alan Cox : Faster /proc handling
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* Alexey Kuznetsov : Massive rework to support tree based routing,
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* routing caches and better behaviour.
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*
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* Olaf Erb : irtt wasn't being copied right.
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* Bjorn Ekwall : Kerneld route support.
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* Alan Cox : Multicast fixed (I hope)
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* Pavel Krauz : Limited broadcast fixed
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* Mike McLagan : Routing by source
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* Alexey Kuznetsov : End of old history. Split to fib.c and
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* route.c and rewritten from scratch.
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* Andi Kleen : Load-limit warning messages.
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* Vitaly E. Lavrov : Transparent proxy revived after year coma.
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* Vitaly E. Lavrov : Race condition in ip_route_input_slow.
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* Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow.
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* Vladimir V. Ivanov : IP rule info (flowid) is really useful.
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* Marc Boucher : routing by fwmark
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* Robert Olsson : Added rt_cache statistics
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* Arnaldo C. Melo : Convert proc stuff to seq_file
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* Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
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* Ilia Sotnikov : Ignore TOS on PMTUD and Redirect
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* Ilia Sotnikov : Removed TOS from hash calculations
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/module.h>
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#include <asm/uaccess.h>
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#include <asm/system.h>
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#include <linux/bitops.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/mm.h>
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#include <linux/bootmem.h>
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#include <linux/string.h>
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#include <linux/socket.h>
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#include <linux/sockios.h>
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#include <linux/errno.h>
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#include <linux/in.h>
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#include <linux/inet.h>
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#include <linux/netdevice.h>
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#include <linux/proc_fs.h>
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#include <linux/init.h>
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#include <linux/workqueue.h>
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#include <linux/skbuff.h>
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#include <linux/inetdevice.h>
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#include <linux/igmp.h>
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#include <linux/pkt_sched.h>
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#include <linux/mroute.h>
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#include <linux/netfilter_ipv4.h>
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#include <linux/random.h>
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#include <linux/jhash.h>
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#include <linux/rcupdate.h>
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#include <linux/times.h>
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#include <linux/slab.h>
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#include <net/dst.h>
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#include <net/net_namespace.h>
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#include <net/protocol.h>
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#include <net/ip.h>
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#include <net/route.h>
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#include <net/inetpeer.h>
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#include <net/sock.h>
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#include <net/ip_fib.h>
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#include <net/arp.h>
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#include <net/tcp.h>
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#include <net/icmp.h>
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#include <net/xfrm.h>
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#include <net/netevent.h>
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#include <net/rtnetlink.h>
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#ifdef CONFIG_SYSCTL
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#include <linux/sysctl.h>
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#endif
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#define RT_FL_TOS(oldflp) \
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((u32)(oldflp->fl4_tos & (IPTOS_RT_MASK | RTO_ONLINK)))
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#define IP_MAX_MTU 0xFFF0
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#define RT_GC_TIMEOUT (300*HZ)
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static int ip_rt_max_size;
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static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
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static int ip_rt_gc_interval __read_mostly = 60 * HZ;
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static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
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static int ip_rt_redirect_number __read_mostly = 9;
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static int ip_rt_redirect_load __read_mostly = HZ / 50;
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static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
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static int ip_rt_error_cost __read_mostly = HZ;
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static int ip_rt_error_burst __read_mostly = 5 * HZ;
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static int ip_rt_gc_elasticity __read_mostly = 8;
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static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
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static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
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static int ip_rt_min_advmss __read_mostly = 256;
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static int rt_chain_length_max __read_mostly = 20;
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static struct delayed_work expires_work;
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static unsigned long expires_ljiffies;
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/*
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* Interface to generic destination cache.
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*/
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static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
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static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
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static unsigned int ipv4_default_mtu(const struct dst_entry *dst);
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static void ipv4_dst_destroy(struct dst_entry *dst);
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static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
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static void ipv4_link_failure(struct sk_buff *skb);
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static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
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static int rt_garbage_collect(struct dst_ops *ops);
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static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
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int how)
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{
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}
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static struct dst_ops ipv4_dst_ops = {
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.family = AF_INET,
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.protocol = cpu_to_be16(ETH_P_IP),
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.gc = rt_garbage_collect,
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.check = ipv4_dst_check,
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.default_advmss = ipv4_default_advmss,
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.default_mtu = ipv4_default_mtu,
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.destroy = ipv4_dst_destroy,
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.ifdown = ipv4_dst_ifdown,
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.negative_advice = ipv4_negative_advice,
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.link_failure = ipv4_link_failure,
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.update_pmtu = ip_rt_update_pmtu,
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.local_out = __ip_local_out,
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};
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#define ECN_OR_COST(class) TC_PRIO_##class
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const __u8 ip_tos2prio[16] = {
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TC_PRIO_BESTEFFORT,
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ECN_OR_COST(FILLER),
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TC_PRIO_BESTEFFORT,
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ECN_OR_COST(BESTEFFORT),
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TC_PRIO_BULK,
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ECN_OR_COST(BULK),
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TC_PRIO_BULK,
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ECN_OR_COST(BULK),
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TC_PRIO_INTERACTIVE,
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ECN_OR_COST(INTERACTIVE),
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TC_PRIO_INTERACTIVE,
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ECN_OR_COST(INTERACTIVE),
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TC_PRIO_INTERACTIVE_BULK,
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ECN_OR_COST(INTERACTIVE_BULK),
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TC_PRIO_INTERACTIVE_BULK,
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ECN_OR_COST(INTERACTIVE_BULK)
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};
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/*
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* Route cache.
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*/
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/* The locking scheme is rather straight forward:
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*
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* 1) Read-Copy Update protects the buckets of the central route hash.
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* 2) Only writers remove entries, and they hold the lock
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* as they look at rtable reference counts.
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* 3) Only readers acquire references to rtable entries,
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* they do so with atomic increments and with the
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* lock held.
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*/
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struct rt_hash_bucket {
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struct rtable __rcu *chain;
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};
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#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
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defined(CONFIG_PROVE_LOCKING)
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/*
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* Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks
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* The size of this table is a power of two and depends on the number of CPUS.
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* (on lockdep we have a quite big spinlock_t, so keep the size down there)
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*/
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#ifdef CONFIG_LOCKDEP
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# define RT_HASH_LOCK_SZ 256
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#else
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# if NR_CPUS >= 32
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# define RT_HASH_LOCK_SZ 4096
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# elif NR_CPUS >= 16
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# define RT_HASH_LOCK_SZ 2048
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# elif NR_CPUS >= 8
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# define RT_HASH_LOCK_SZ 1024
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# elif NR_CPUS >= 4
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# define RT_HASH_LOCK_SZ 512
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# else
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# define RT_HASH_LOCK_SZ 256
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# endif
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#endif
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static spinlock_t *rt_hash_locks;
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# define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)]
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static __init void rt_hash_lock_init(void)
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{
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int i;
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rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ,
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GFP_KERNEL);
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if (!rt_hash_locks)
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panic("IP: failed to allocate rt_hash_locks\n");
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for (i = 0; i < RT_HASH_LOCK_SZ; i++)
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spin_lock_init(&rt_hash_locks[i]);
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}
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#else
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# define rt_hash_lock_addr(slot) NULL
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static inline void rt_hash_lock_init(void)
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{
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}
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#endif
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static struct rt_hash_bucket *rt_hash_table __read_mostly;
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static unsigned rt_hash_mask __read_mostly;
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static unsigned int rt_hash_log __read_mostly;
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static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
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#define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
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static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx,
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int genid)
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{
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return jhash_3words((__force u32)daddr, (__force u32)saddr,
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idx, genid)
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& rt_hash_mask;
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}
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static inline int rt_genid(struct net *net)
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{
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return atomic_read(&net->ipv4.rt_genid);
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}
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#ifdef CONFIG_PROC_FS
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struct rt_cache_iter_state {
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struct seq_net_private p;
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int bucket;
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int genid;
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};
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static struct rtable *rt_cache_get_first(struct seq_file *seq)
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{
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struct rt_cache_iter_state *st = seq->private;
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struct rtable *r = NULL;
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for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) {
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if (!rcu_dereference_raw(rt_hash_table[st->bucket].chain))
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continue;
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rcu_read_lock_bh();
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r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
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while (r) {
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if (dev_net(r->dst.dev) == seq_file_net(seq) &&
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r->rt_genid == st->genid)
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return r;
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r = rcu_dereference_bh(r->dst.rt_next);
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}
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rcu_read_unlock_bh();
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}
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return r;
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}
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static struct rtable *__rt_cache_get_next(struct seq_file *seq,
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struct rtable *r)
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{
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struct rt_cache_iter_state *st = seq->private;
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r = rcu_dereference_bh(r->dst.rt_next);
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while (!r) {
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rcu_read_unlock_bh();
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do {
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if (--st->bucket < 0)
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return NULL;
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} while (!rcu_dereference_raw(rt_hash_table[st->bucket].chain));
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rcu_read_lock_bh();
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r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
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}
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return r;
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}
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static struct rtable *rt_cache_get_next(struct seq_file *seq,
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struct rtable *r)
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{
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struct rt_cache_iter_state *st = seq->private;
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while ((r = __rt_cache_get_next(seq, r)) != NULL) {
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if (dev_net(r->dst.dev) != seq_file_net(seq))
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continue;
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if (r->rt_genid == st->genid)
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break;
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}
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return r;
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}
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static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)
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{
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struct rtable *r = rt_cache_get_first(seq);
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if (r)
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while (pos && (r = rt_cache_get_next(seq, r)))
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--pos;
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return pos ? NULL : r;
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}
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static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
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{
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struct rt_cache_iter_state *st = seq->private;
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if (*pos)
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return rt_cache_get_idx(seq, *pos - 1);
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st->genid = rt_genid(seq_file_net(seq));
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return SEQ_START_TOKEN;
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}
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static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
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{
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struct rtable *r;
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if (v == SEQ_START_TOKEN)
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r = rt_cache_get_first(seq);
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else
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r = rt_cache_get_next(seq, v);
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++*pos;
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return r;
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}
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static void rt_cache_seq_stop(struct seq_file *seq, void *v)
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{
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if (v && v != SEQ_START_TOKEN)
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rcu_read_unlock_bh();
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}
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static int rt_cache_seq_show(struct seq_file *seq, void *v)
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{
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if (v == SEQ_START_TOKEN)
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seq_printf(seq, "%-127s\n",
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"Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
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"Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
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"HHUptod\tSpecDst");
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else {
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struct rtable *r = v;
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int len;
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seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t"
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"%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n",
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r->dst.dev ? r->dst.dev->name : "*",
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(__force u32)r->rt_dst,
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(__force u32)r->rt_gateway,
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r->rt_flags, atomic_read(&r->dst.__refcnt),
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r->dst.__use, 0, (__force u32)r->rt_src,
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dst_metric_advmss(&r->dst) + 40,
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dst_metric(&r->dst, RTAX_WINDOW),
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(int)((dst_metric(&r->dst, RTAX_RTT) >> 3) +
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dst_metric(&r->dst, RTAX_RTTVAR)),
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r->fl.fl4_tos,
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r->dst.hh ? atomic_read(&r->dst.hh->hh_refcnt) : -1,
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r->dst.hh ? (r->dst.hh->hh_output ==
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dev_queue_xmit) : 0,
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r->rt_spec_dst, &len);
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seq_printf(seq, "%*s\n", 127 - len, "");
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}
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return 0;
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}
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static const struct seq_operations rt_cache_seq_ops = {
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.start = rt_cache_seq_start,
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.next = rt_cache_seq_next,
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.stop = rt_cache_seq_stop,
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.show = rt_cache_seq_show,
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};
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static int rt_cache_seq_open(struct inode *inode, struct file *file)
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{
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return seq_open_net(inode, file, &rt_cache_seq_ops,
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sizeof(struct rt_cache_iter_state));
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}
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static const struct file_operations rt_cache_seq_fops = {
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.owner = THIS_MODULE,
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.open = rt_cache_seq_open,
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.read = seq_read,
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.llseek = seq_lseek,
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.release = seq_release_net,
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};
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static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
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{
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int cpu;
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if (*pos == 0)
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return SEQ_START_TOKEN;
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for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
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if (!cpu_possible(cpu))
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continue;
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*pos = cpu+1;
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return &per_cpu(rt_cache_stat, cpu);
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}
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return NULL;
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}
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static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
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{
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int cpu;
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for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
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if (!cpu_possible(cpu))
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continue;
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*pos = cpu+1;
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return &per_cpu(rt_cache_stat, cpu);
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}
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return NULL;
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}
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static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
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{
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}
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static int rt_cpu_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
struct rt_cache_stat *st = v;
|
|
|
|
if (v == SEQ_START_TOKEN) {
|
|
seq_printf(seq, "entries in_hit in_slow_tot in_slow_mc in_no_route in_brd in_martian_dst in_martian_src out_hit out_slow_tot out_slow_mc gc_total gc_ignored gc_goal_miss gc_dst_overflow in_hlist_search out_hlist_search\n");
|
|
return 0;
|
|
}
|
|
|
|
seq_printf(seq,"%08x %08x %08x %08x %08x %08x %08x %08x "
|
|
" %08x %08x %08x %08x %08x %08x %08x %08x %08x \n",
|
|
dst_entries_get_slow(&ipv4_dst_ops),
|
|
st->in_hit,
|
|
st->in_slow_tot,
|
|
st->in_slow_mc,
|
|
st->in_no_route,
|
|
st->in_brd,
|
|
st->in_martian_dst,
|
|
st->in_martian_src,
|
|
|
|
st->out_hit,
|
|
st->out_slow_tot,
|
|
st->out_slow_mc,
|
|
|
|
st->gc_total,
|
|
st->gc_ignored,
|
|
st->gc_goal_miss,
|
|
st->gc_dst_overflow,
|
|
st->in_hlist_search,
|
|
st->out_hlist_search
|
|
);
|
|
return 0;
|
|
}
|
|
|
|
static const struct seq_operations rt_cpu_seq_ops = {
|
|
.start = rt_cpu_seq_start,
|
|
.next = rt_cpu_seq_next,
|
|
.stop = rt_cpu_seq_stop,
|
|
.show = rt_cpu_seq_show,
|
|
};
|
|
|
|
|
|
static int rt_cpu_seq_open(struct inode *inode, struct file *file)
|
|
{
|
|
return seq_open(file, &rt_cpu_seq_ops);
|
|
}
|
|
|
|
static const struct file_operations rt_cpu_seq_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = rt_cpu_seq_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = seq_release,
|
|
};
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
static int rt_acct_proc_show(struct seq_file *m, void *v)
|
|
{
|
|
struct ip_rt_acct *dst, *src;
|
|
unsigned int i, j;
|
|
|
|
dst = kcalloc(256, sizeof(struct ip_rt_acct), GFP_KERNEL);
|
|
if (!dst)
|
|
return -ENOMEM;
|
|
|
|
for_each_possible_cpu(i) {
|
|
src = (struct ip_rt_acct *)per_cpu_ptr(ip_rt_acct, i);
|
|
for (j = 0; j < 256; j++) {
|
|
dst[j].o_bytes += src[j].o_bytes;
|
|
dst[j].o_packets += src[j].o_packets;
|
|
dst[j].i_bytes += src[j].i_bytes;
|
|
dst[j].i_packets += src[j].i_packets;
|
|
}
|
|
}
|
|
|
|
seq_write(m, dst, 256 * sizeof(struct ip_rt_acct));
|
|
kfree(dst);
|
|
return 0;
|
|
}
|
|
|
|
static int rt_acct_proc_open(struct inode *inode, struct file *file)
|
|
{
|
|
return single_open(file, rt_acct_proc_show, NULL);
|
|
}
|
|
|
|
static const struct file_operations rt_acct_proc_fops = {
|
|
.owner = THIS_MODULE,
|
|
.open = rt_acct_proc_open,
|
|
.read = seq_read,
|
|
.llseek = seq_lseek,
|
|
.release = single_release,
|
|
};
|
|
#endif
|
|
|
|
static int __net_init ip_rt_do_proc_init(struct net *net)
|
|
{
|
|
struct proc_dir_entry *pde;
|
|
|
|
pde = proc_net_fops_create(net, "rt_cache", S_IRUGO,
|
|
&rt_cache_seq_fops);
|
|
if (!pde)
|
|
goto err1;
|
|
|
|
pde = proc_create("rt_cache", S_IRUGO,
|
|
net->proc_net_stat, &rt_cpu_seq_fops);
|
|
if (!pde)
|
|
goto err2;
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
|
|
if (!pde)
|
|
goto err3;
|
|
#endif
|
|
return 0;
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
err3:
|
|
remove_proc_entry("rt_cache", net->proc_net_stat);
|
|
#endif
|
|
err2:
|
|
remove_proc_entry("rt_cache", net->proc_net);
|
|
err1:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void __net_exit ip_rt_do_proc_exit(struct net *net)
|
|
{
|
|
remove_proc_entry("rt_cache", net->proc_net_stat);
|
|
remove_proc_entry("rt_cache", net->proc_net);
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
remove_proc_entry("rt_acct", net->proc_net);
|
|
#endif
|
|
}
|
|
|
|
static struct pernet_operations ip_rt_proc_ops __net_initdata = {
|
|
.init = ip_rt_do_proc_init,
|
|
.exit = ip_rt_do_proc_exit,
|
|
};
|
|
|
|
static int __init ip_rt_proc_init(void)
|
|
{
|
|
return register_pernet_subsys(&ip_rt_proc_ops);
|
|
}
|
|
|
|
#else
|
|
static inline int ip_rt_proc_init(void)
|
|
{
|
|
return 0;
|
|
}
|
|
#endif /* CONFIG_PROC_FS */
|
|
|
|
static inline void rt_free(struct rtable *rt)
|
|
{
|
|
call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
|
|
}
|
|
|
|
static inline void rt_drop(struct rtable *rt)
|
|
{
|
|
ip_rt_put(rt);
|
|
call_rcu_bh(&rt->dst.rcu_head, dst_rcu_free);
|
|
}
|
|
|
|
static inline int rt_fast_clean(struct rtable *rth)
|
|
{
|
|
/* Kill broadcast/multicast entries very aggresively, if they
|
|
collide in hash table with more useful entries */
|
|
return (rth->rt_flags & (RTCF_BROADCAST | RTCF_MULTICAST)) &&
|
|
rt_is_input_route(rth) && rth->dst.rt_next;
|
|
}
|
|
|
|
static inline int rt_valuable(struct rtable *rth)
|
|
{
|
|
return (rth->rt_flags & (RTCF_REDIRECTED | RTCF_NOTIFY)) ||
|
|
rth->dst.expires;
|
|
}
|
|
|
|
static int rt_may_expire(struct rtable *rth, unsigned long tmo1, unsigned long tmo2)
|
|
{
|
|
unsigned long age;
|
|
int ret = 0;
|
|
|
|
if (atomic_read(&rth->dst.__refcnt))
|
|
goto out;
|
|
|
|
ret = 1;
|
|
if (rth->dst.expires &&
|
|
time_after_eq(jiffies, rth->dst.expires))
|
|
goto out;
|
|
|
|
age = jiffies - rth->dst.lastuse;
|
|
ret = 0;
|
|
if ((age <= tmo1 && !rt_fast_clean(rth)) ||
|
|
(age <= tmo2 && rt_valuable(rth)))
|
|
goto out;
|
|
ret = 1;
|
|
out: return ret;
|
|
}
|
|
|
|
/* Bits of score are:
|
|
* 31: very valuable
|
|
* 30: not quite useless
|
|
* 29..0: usage counter
|
|
*/
|
|
static inline u32 rt_score(struct rtable *rt)
|
|
{
|
|
u32 score = jiffies - rt->dst.lastuse;
|
|
|
|
score = ~score & ~(3<<30);
|
|
|
|
if (rt_valuable(rt))
|
|
score |= (1<<31);
|
|
|
|
if (rt_is_output_route(rt) ||
|
|
!(rt->rt_flags & (RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL)))
|
|
score |= (1<<30);
|
|
|
|
return score;
|
|
}
|
|
|
|
static inline bool rt_caching(const struct net *net)
|
|
{
|
|
return net->ipv4.current_rt_cache_rebuild_count <=
|
|
net->ipv4.sysctl_rt_cache_rebuild_count;
|
|
}
|
|
|
|
static inline bool compare_hash_inputs(const struct flowi *fl1,
|
|
const struct flowi *fl2)
|
|
{
|
|
return ((((__force u32)fl1->fl4_dst ^ (__force u32)fl2->fl4_dst) |
|
|
((__force u32)fl1->fl4_src ^ (__force u32)fl2->fl4_src) |
|
|
(fl1->iif ^ fl2->iif)) == 0);
|
|
}
|
|
|
|
static inline int compare_keys(struct flowi *fl1, struct flowi *fl2)
|
|
{
|
|
return (((__force u32)fl1->fl4_dst ^ (__force u32)fl2->fl4_dst) |
|
|
((__force u32)fl1->fl4_src ^ (__force u32)fl2->fl4_src) |
|
|
(fl1->mark ^ fl2->mark) |
|
|
(*(u16 *)&fl1->fl4_tos ^ *(u16 *)&fl2->fl4_tos) |
|
|
(fl1->oif ^ fl2->oif) |
|
|
(fl1->iif ^ fl2->iif)) == 0;
|
|
}
|
|
|
|
static inline int compare_netns(struct rtable *rt1, struct rtable *rt2)
|
|
{
|
|
return net_eq(dev_net(rt1->dst.dev), dev_net(rt2->dst.dev));
|
|
}
|
|
|
|
static inline int rt_is_expired(struct rtable *rth)
|
|
{
|
|
return rth->rt_genid != rt_genid(dev_net(rth->dst.dev));
|
|
}
|
|
|
|
/*
|
|
* Perform a full scan of hash table and free all entries.
|
|
* Can be called by a softirq or a process.
|
|
* In the later case, we want to be reschedule if necessary
|
|
*/
|
|
static void rt_do_flush(struct net *net, int process_context)
|
|
{
|
|
unsigned int i;
|
|
struct rtable *rth, *next;
|
|
|
|
for (i = 0; i <= rt_hash_mask; i++) {
|
|
struct rtable __rcu **pprev;
|
|
struct rtable *list;
|
|
|
|
if (process_context && need_resched())
|
|
cond_resched();
|
|
rth = rcu_dereference_raw(rt_hash_table[i].chain);
|
|
if (!rth)
|
|
continue;
|
|
|
|
spin_lock_bh(rt_hash_lock_addr(i));
|
|
|
|
list = NULL;
|
|
pprev = &rt_hash_table[i].chain;
|
|
rth = rcu_dereference_protected(*pprev,
|
|
lockdep_is_held(rt_hash_lock_addr(i)));
|
|
|
|
while (rth) {
|
|
next = rcu_dereference_protected(rth->dst.rt_next,
|
|
lockdep_is_held(rt_hash_lock_addr(i)));
|
|
|
|
if (!net ||
|
|
net_eq(dev_net(rth->dst.dev), net)) {
|
|
rcu_assign_pointer(*pprev, next);
|
|
rcu_assign_pointer(rth->dst.rt_next, list);
|
|
list = rth;
|
|
} else {
|
|
pprev = &rth->dst.rt_next;
|
|
}
|
|
rth = next;
|
|
}
|
|
|
|
spin_unlock_bh(rt_hash_lock_addr(i));
|
|
|
|
for (; list; list = next) {
|
|
next = rcu_dereference_protected(list->dst.rt_next, 1);
|
|
rt_free(list);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* While freeing expired entries, we compute average chain length
|
|
* and standard deviation, using fixed-point arithmetic.
|
|
* This to have an estimation of rt_chain_length_max
|
|
* rt_chain_length_max = max(elasticity, AVG + 4*SD)
|
|
* We use 3 bits for frational part, and 29 (or 61) for magnitude.
|
|
*/
|
|
|
|
#define FRACT_BITS 3
|
|
#define ONE (1UL << FRACT_BITS)
|
|
|
|
/*
|
|
* Given a hash chain and an item in this hash chain,
|
|
* find if a previous entry has the same hash_inputs
|
|
* (but differs on tos, mark or oif)
|
|
* Returns 0 if an alias is found.
|
|
* Returns ONE if rth has no alias before itself.
|
|
*/
|
|
static int has_noalias(const struct rtable *head, const struct rtable *rth)
|
|
{
|
|
const struct rtable *aux = head;
|
|
|
|
while (aux != rth) {
|
|
if (compare_hash_inputs(&aux->fl, &rth->fl))
|
|
return 0;
|
|
aux = rcu_dereference_protected(aux->dst.rt_next, 1);
|
|
}
|
|
return ONE;
|
|
}
|
|
|
|
static void rt_check_expire(void)
|
|
{
|
|
static unsigned int rover;
|
|
unsigned int i = rover, goal;
|
|
struct rtable *rth;
|
|
struct rtable __rcu **rthp;
|
|
unsigned long samples = 0;
|
|
unsigned long sum = 0, sum2 = 0;
|
|
unsigned long delta;
|
|
u64 mult;
|
|
|
|
delta = jiffies - expires_ljiffies;
|
|
expires_ljiffies = jiffies;
|
|
mult = ((u64)delta) << rt_hash_log;
|
|
if (ip_rt_gc_timeout > 1)
|
|
do_div(mult, ip_rt_gc_timeout);
|
|
goal = (unsigned int)mult;
|
|
if (goal > rt_hash_mask)
|
|
goal = rt_hash_mask + 1;
|
|
for (; goal > 0; goal--) {
|
|
unsigned long tmo = ip_rt_gc_timeout;
|
|
unsigned long length;
|
|
|
|
i = (i + 1) & rt_hash_mask;
|
|
rthp = &rt_hash_table[i].chain;
|
|
|
|
if (need_resched())
|
|
cond_resched();
|
|
|
|
samples++;
|
|
|
|
if (rcu_dereference_raw(*rthp) == NULL)
|
|
continue;
|
|
length = 0;
|
|
spin_lock_bh(rt_hash_lock_addr(i));
|
|
while ((rth = rcu_dereference_protected(*rthp,
|
|
lockdep_is_held(rt_hash_lock_addr(i)))) != NULL) {
|
|
prefetch(rth->dst.rt_next);
|
|
if (rt_is_expired(rth)) {
|
|
*rthp = rth->dst.rt_next;
|
|
rt_free(rth);
|
|
continue;
|
|
}
|
|
if (rth->dst.expires) {
|
|
/* Entry is expired even if it is in use */
|
|
if (time_before_eq(jiffies, rth->dst.expires)) {
|
|
nofree:
|
|
tmo >>= 1;
|
|
rthp = &rth->dst.rt_next;
|
|
/*
|
|
* We only count entries on
|
|
* a chain with equal hash inputs once
|
|
* so that entries for different QOS
|
|
* levels, and other non-hash input
|
|
* attributes don't unfairly skew
|
|
* the length computation
|
|
*/
|
|
length += has_noalias(rt_hash_table[i].chain, rth);
|
|
continue;
|
|
}
|
|
} else if (!rt_may_expire(rth, tmo, ip_rt_gc_timeout))
|
|
goto nofree;
|
|
|
|
/* Cleanup aged off entries. */
|
|
*rthp = rth->dst.rt_next;
|
|
rt_free(rth);
|
|
}
|
|
spin_unlock_bh(rt_hash_lock_addr(i));
|
|
sum += length;
|
|
sum2 += length*length;
|
|
}
|
|
if (samples) {
|
|
unsigned long avg = sum / samples;
|
|
unsigned long sd = int_sqrt(sum2 / samples - avg*avg);
|
|
rt_chain_length_max = max_t(unsigned long,
|
|
ip_rt_gc_elasticity,
|
|
(avg + 4*sd) >> FRACT_BITS);
|
|
}
|
|
rover = i;
|
|
}
|
|
|
|
/*
|
|
* rt_worker_func() is run in process context.
|
|
* we call rt_check_expire() to scan part of the hash table
|
|
*/
|
|
static void rt_worker_func(struct work_struct *work)
|
|
{
|
|
rt_check_expire();
|
|
schedule_delayed_work(&expires_work, ip_rt_gc_interval);
|
|
}
|
|
|
|
/*
|
|
* Pertubation of rt_genid by a small quantity [1..256]
|
|
* Using 8 bits of shuffling ensure we can call rt_cache_invalidate()
|
|
* many times (2^24) without giving recent rt_genid.
|
|
* Jenkins hash is strong enough that litle changes of rt_genid are OK.
|
|
*/
|
|
static void rt_cache_invalidate(struct net *net)
|
|
{
|
|
unsigned char shuffle;
|
|
|
|
get_random_bytes(&shuffle, sizeof(shuffle));
|
|
atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
|
|
}
|
|
|
|
/*
|
|
* delay < 0 : invalidate cache (fast : entries will be deleted later)
|
|
* delay >= 0 : invalidate & flush cache (can be long)
|
|
*/
|
|
void rt_cache_flush(struct net *net, int delay)
|
|
{
|
|
rt_cache_invalidate(net);
|
|
if (delay >= 0)
|
|
rt_do_flush(net, !in_softirq());
|
|
}
|
|
|
|
/* Flush previous cache invalidated entries from the cache */
|
|
void rt_cache_flush_batch(struct net *net)
|
|
{
|
|
rt_do_flush(net, !in_softirq());
|
|
}
|
|
|
|
static void rt_emergency_hash_rebuild(struct net *net)
|
|
{
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "Route hash chain too long!\n");
|
|
rt_cache_invalidate(net);
|
|
}
|
|
|
|
/*
|
|
Short description of GC goals.
|
|
|
|
We want to build algorithm, which will keep routing cache
|
|
at some equilibrium point, when number of aged off entries
|
|
is kept approximately equal to newly generated ones.
|
|
|
|
Current expiration strength is variable "expire".
|
|
We try to adjust it dynamically, so that if networking
|
|
is idle expires is large enough to keep enough of warm entries,
|
|
and when load increases it reduces to limit cache size.
|
|
*/
|
|
|
|
static int rt_garbage_collect(struct dst_ops *ops)
|
|
{
|
|
static unsigned long expire = RT_GC_TIMEOUT;
|
|
static unsigned long last_gc;
|
|
static int rover;
|
|
static int equilibrium;
|
|
struct rtable *rth;
|
|
struct rtable __rcu **rthp;
|
|
unsigned long now = jiffies;
|
|
int goal;
|
|
int entries = dst_entries_get_fast(&ipv4_dst_ops);
|
|
|
|
/*
|
|
* Garbage collection is pretty expensive,
|
|
* do not make it too frequently.
|
|
*/
|
|
|
|
RT_CACHE_STAT_INC(gc_total);
|
|
|
|
if (now - last_gc < ip_rt_gc_min_interval &&
|
|
entries < ip_rt_max_size) {
|
|
RT_CACHE_STAT_INC(gc_ignored);
|
|
goto out;
|
|
}
|
|
|
|
entries = dst_entries_get_slow(&ipv4_dst_ops);
|
|
/* Calculate number of entries, which we want to expire now. */
|
|
goal = entries - (ip_rt_gc_elasticity << rt_hash_log);
|
|
if (goal <= 0) {
|
|
if (equilibrium < ipv4_dst_ops.gc_thresh)
|
|
equilibrium = ipv4_dst_ops.gc_thresh;
|
|
goal = entries - equilibrium;
|
|
if (goal > 0) {
|
|
equilibrium += min_t(unsigned int, goal >> 1, rt_hash_mask + 1);
|
|
goal = entries - equilibrium;
|
|
}
|
|
} else {
|
|
/* We are in dangerous area. Try to reduce cache really
|
|
* aggressively.
|
|
*/
|
|
goal = max_t(unsigned int, goal >> 1, rt_hash_mask + 1);
|
|
equilibrium = entries - goal;
|
|
}
|
|
|
|
if (now - last_gc >= ip_rt_gc_min_interval)
|
|
last_gc = now;
|
|
|
|
if (goal <= 0) {
|
|
equilibrium += goal;
|
|
goto work_done;
|
|
}
|
|
|
|
do {
|
|
int i, k;
|
|
|
|
for (i = rt_hash_mask, k = rover; i >= 0; i--) {
|
|
unsigned long tmo = expire;
|
|
|
|
k = (k + 1) & rt_hash_mask;
|
|
rthp = &rt_hash_table[k].chain;
|
|
spin_lock_bh(rt_hash_lock_addr(k));
|
|
while ((rth = rcu_dereference_protected(*rthp,
|
|
lockdep_is_held(rt_hash_lock_addr(k)))) != NULL) {
|
|
if (!rt_is_expired(rth) &&
|
|
!rt_may_expire(rth, tmo, expire)) {
|
|
tmo >>= 1;
|
|
rthp = &rth->dst.rt_next;
|
|
continue;
|
|
}
|
|
*rthp = rth->dst.rt_next;
|
|
rt_free(rth);
|
|
goal--;
|
|
}
|
|
spin_unlock_bh(rt_hash_lock_addr(k));
|
|
if (goal <= 0)
|
|
break;
|
|
}
|
|
rover = k;
|
|
|
|
if (goal <= 0)
|
|
goto work_done;
|
|
|
|
/* Goal is not achieved. We stop process if:
|
|
|
|
- if expire reduced to zero. Otherwise, expire is halfed.
|
|
- if table is not full.
|
|
- if we are called from interrupt.
|
|
- jiffies check is just fallback/debug loop breaker.
|
|
We will not spin here for long time in any case.
|
|
*/
|
|
|
|
RT_CACHE_STAT_INC(gc_goal_miss);
|
|
|
|
if (expire == 0)
|
|
break;
|
|
|
|
expire >>= 1;
|
|
#if RT_CACHE_DEBUG >= 2
|
|
printk(KERN_DEBUG "expire>> %u %d %d %d\n", expire,
|
|
dst_entries_get_fast(&ipv4_dst_ops), goal, i);
|
|
#endif
|
|
|
|
if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size)
|
|
goto out;
|
|
} while (!in_softirq() && time_before_eq(jiffies, now));
|
|
|
|
if (dst_entries_get_fast(&ipv4_dst_ops) < ip_rt_max_size)
|
|
goto out;
|
|
if (dst_entries_get_slow(&ipv4_dst_ops) < ip_rt_max_size)
|
|
goto out;
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "dst cache overflow\n");
|
|
RT_CACHE_STAT_INC(gc_dst_overflow);
|
|
return 1;
|
|
|
|
work_done:
|
|
expire += ip_rt_gc_min_interval;
|
|
if (expire > ip_rt_gc_timeout ||
|
|
dst_entries_get_fast(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh ||
|
|
dst_entries_get_slow(&ipv4_dst_ops) < ipv4_dst_ops.gc_thresh)
|
|
expire = ip_rt_gc_timeout;
|
|
#if RT_CACHE_DEBUG >= 2
|
|
printk(KERN_DEBUG "expire++ %u %d %d %d\n", expire,
|
|
dst_entries_get_fast(&ipv4_dst_ops), goal, rover);
|
|
#endif
|
|
out: return 0;
|
|
}
|
|
|
|
/*
|
|
* Returns number of entries in a hash chain that have different hash_inputs
|
|
*/
|
|
static int slow_chain_length(const struct rtable *head)
|
|
{
|
|
int length = 0;
|
|
const struct rtable *rth = head;
|
|
|
|
while (rth) {
|
|
length += has_noalias(head, rth);
|
|
rth = rcu_dereference_protected(rth->dst.rt_next, 1);
|
|
}
|
|
return length >> FRACT_BITS;
|
|
}
|
|
|
|
static int rt_intern_hash(unsigned hash, struct rtable *rt,
|
|
struct rtable **rp, struct sk_buff *skb, int ifindex)
|
|
{
|
|
struct rtable *rth, *cand;
|
|
struct rtable __rcu **rthp, **candp;
|
|
unsigned long now;
|
|
u32 min_score;
|
|
int chain_length;
|
|
int attempts = !in_softirq();
|
|
|
|
restart:
|
|
chain_length = 0;
|
|
min_score = ~(u32)0;
|
|
cand = NULL;
|
|
candp = NULL;
|
|
now = jiffies;
|
|
|
|
if (!rt_caching(dev_net(rt->dst.dev))) {
|
|
/*
|
|
* If we're not caching, just tell the caller we
|
|
* were successful and don't touch the route. The
|
|
* caller hold the sole reference to the cache entry, and
|
|
* it will be released when the caller is done with it.
|
|
* If we drop it here, the callers have no way to resolve routes
|
|
* when we're not caching. Instead, just point *rp at rt, so
|
|
* the caller gets a single use out of the route
|
|
* Note that we do rt_free on this new route entry, so that
|
|
* once its refcount hits zero, we are still able to reap it
|
|
* (Thanks Alexey)
|
|
* Note: To avoid expensive rcu stuff for this uncached dst,
|
|
* we set DST_NOCACHE so that dst_release() can free dst without
|
|
* waiting a grace period.
|
|
*/
|
|
|
|
rt->dst.flags |= DST_NOCACHE;
|
|
if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
|
|
int err = arp_bind_neighbour(&rt->dst);
|
|
if (err) {
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING
|
|
"Neighbour table failure & not caching routes.\n");
|
|
ip_rt_put(rt);
|
|
return err;
|
|
}
|
|
}
|
|
|
|
goto skip_hashing;
|
|
}
|
|
|
|
rthp = &rt_hash_table[hash].chain;
|
|
|
|
spin_lock_bh(rt_hash_lock_addr(hash));
|
|
while ((rth = rcu_dereference_protected(*rthp,
|
|
lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) {
|
|
if (rt_is_expired(rth)) {
|
|
*rthp = rth->dst.rt_next;
|
|
rt_free(rth);
|
|
continue;
|
|
}
|
|
if (compare_keys(&rth->fl, &rt->fl) && compare_netns(rth, rt)) {
|
|
/* Put it first */
|
|
*rthp = rth->dst.rt_next;
|
|
/*
|
|
* Since lookup is lockfree, the deletion
|
|
* must be visible to another weakly ordered CPU before
|
|
* the insertion at the start of the hash chain.
|
|
*/
|
|
rcu_assign_pointer(rth->dst.rt_next,
|
|
rt_hash_table[hash].chain);
|
|
/*
|
|
* Since lookup is lockfree, the update writes
|
|
* must be ordered for consistency on SMP.
|
|
*/
|
|
rcu_assign_pointer(rt_hash_table[hash].chain, rth);
|
|
|
|
dst_use(&rth->dst, now);
|
|
spin_unlock_bh(rt_hash_lock_addr(hash));
|
|
|
|
rt_drop(rt);
|
|
if (rp)
|
|
*rp = rth;
|
|
else
|
|
skb_dst_set(skb, &rth->dst);
|
|
return 0;
|
|
}
|
|
|
|
if (!atomic_read(&rth->dst.__refcnt)) {
|
|
u32 score = rt_score(rth);
|
|
|
|
if (score <= min_score) {
|
|
cand = rth;
|
|
candp = rthp;
|
|
min_score = score;
|
|
}
|
|
}
|
|
|
|
chain_length++;
|
|
|
|
rthp = &rth->dst.rt_next;
|
|
}
|
|
|
|
if (cand) {
|
|
/* ip_rt_gc_elasticity used to be average length of chain
|
|
* length, when exceeded gc becomes really aggressive.
|
|
*
|
|
* The second limit is less certain. At the moment it allows
|
|
* only 2 entries per bucket. We will see.
|
|
*/
|
|
if (chain_length > ip_rt_gc_elasticity) {
|
|
*candp = cand->dst.rt_next;
|
|
rt_free(cand);
|
|
}
|
|
} else {
|
|
if (chain_length > rt_chain_length_max &&
|
|
slow_chain_length(rt_hash_table[hash].chain) > rt_chain_length_max) {
|
|
struct net *net = dev_net(rt->dst.dev);
|
|
int num = ++net->ipv4.current_rt_cache_rebuild_count;
|
|
if (!rt_caching(net)) {
|
|
printk(KERN_WARNING "%s: %d rebuilds is over limit, route caching disabled\n",
|
|
rt->dst.dev->name, num);
|
|
}
|
|
rt_emergency_hash_rebuild(net);
|
|
spin_unlock_bh(rt_hash_lock_addr(hash));
|
|
|
|
hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
|
|
ifindex, rt_genid(net));
|
|
goto restart;
|
|
}
|
|
}
|
|
|
|
/* Try to bind route to arp only if it is output
|
|
route or unicast forwarding path.
|
|
*/
|
|
if (rt->rt_type == RTN_UNICAST || rt_is_output_route(rt)) {
|
|
int err = arp_bind_neighbour(&rt->dst);
|
|
if (err) {
|
|
spin_unlock_bh(rt_hash_lock_addr(hash));
|
|
|
|
if (err != -ENOBUFS) {
|
|
rt_drop(rt);
|
|
return err;
|
|
}
|
|
|
|
/* Neighbour tables are full and nothing
|
|
can be released. Try to shrink route cache,
|
|
it is most likely it holds some neighbour records.
|
|
*/
|
|
if (attempts-- > 0) {
|
|
int saved_elasticity = ip_rt_gc_elasticity;
|
|
int saved_int = ip_rt_gc_min_interval;
|
|
ip_rt_gc_elasticity = 1;
|
|
ip_rt_gc_min_interval = 0;
|
|
rt_garbage_collect(&ipv4_dst_ops);
|
|
ip_rt_gc_min_interval = saved_int;
|
|
ip_rt_gc_elasticity = saved_elasticity;
|
|
goto restart;
|
|
}
|
|
|
|
if (net_ratelimit())
|
|
printk(KERN_WARNING "ipv4: Neighbour table overflow.\n");
|
|
rt_drop(rt);
|
|
return -ENOBUFS;
|
|
}
|
|
}
|
|
|
|
rt->dst.rt_next = rt_hash_table[hash].chain;
|
|
|
|
#if RT_CACHE_DEBUG >= 2
|
|
if (rt->dst.rt_next) {
|
|
struct rtable *trt;
|
|
printk(KERN_DEBUG "rt_cache @%02x: %pI4",
|
|
hash, &rt->rt_dst);
|
|
for (trt = rt->dst.rt_next; trt; trt = trt->dst.rt_next)
|
|
printk(" . %pI4", &trt->rt_dst);
|
|
printk("\n");
|
|
}
|
|
#endif
|
|
/*
|
|
* Since lookup is lockfree, we must make sure
|
|
* previous writes to rt are comitted to memory
|
|
* before making rt visible to other CPUS.
|
|
*/
|
|
rcu_assign_pointer(rt_hash_table[hash].chain, rt);
|
|
|
|
spin_unlock_bh(rt_hash_lock_addr(hash));
|
|
|
|
skip_hashing:
|
|
if (rp)
|
|
*rp = rt;
|
|
else
|
|
skb_dst_set(skb, &rt->dst);
|
|
return 0;
|
|
}
|
|
|
|
void rt_bind_peer(struct rtable *rt, int create)
|
|
{
|
|
struct inet_peer *peer;
|
|
|
|
peer = inet_getpeer_v4(rt->rt_dst, create);
|
|
|
|
if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL)
|
|
inet_putpeer(peer);
|
|
}
|
|
|
|
/*
|
|
* Peer allocation may fail only in serious out-of-memory conditions. However
|
|
* we still can generate some output.
|
|
* Random ID selection looks a bit dangerous because we have no chances to
|
|
* select ID being unique in a reasonable period of time.
|
|
* But broken packet identifier may be better than no packet at all.
|
|
*/
|
|
static void ip_select_fb_ident(struct iphdr *iph)
|
|
{
|
|
static DEFINE_SPINLOCK(ip_fb_id_lock);
|
|
static u32 ip_fallback_id;
|
|
u32 salt;
|
|
|
|
spin_lock_bh(&ip_fb_id_lock);
|
|
salt = secure_ip_id((__force __be32)ip_fallback_id ^ iph->daddr);
|
|
iph->id = htons(salt & 0xFFFF);
|
|
ip_fallback_id = salt;
|
|
spin_unlock_bh(&ip_fb_id_lock);
|
|
}
|
|
|
|
void __ip_select_ident(struct iphdr *iph, struct dst_entry *dst, int more)
|
|
{
|
|
struct rtable *rt = (struct rtable *) dst;
|
|
|
|
if (rt) {
|
|
if (rt->peer == NULL)
|
|
rt_bind_peer(rt, 1);
|
|
|
|
/* If peer is attached to destination, it is never detached,
|
|
so that we need not to grab a lock to dereference it.
|
|
*/
|
|
if (rt->peer) {
|
|
iph->id = htons(inet_getid(rt->peer, more));
|
|
return;
|
|
}
|
|
} else
|
|
printk(KERN_DEBUG "rt_bind_peer(0) @%p\n",
|
|
__builtin_return_address(0));
|
|
|
|
ip_select_fb_ident(iph);
|
|
}
|
|
EXPORT_SYMBOL(__ip_select_ident);
|
|
|
|
static void rt_del(unsigned hash, struct rtable *rt)
|
|
{
|
|
struct rtable __rcu **rthp;
|
|
struct rtable *aux;
|
|
|
|
rthp = &rt_hash_table[hash].chain;
|
|
spin_lock_bh(rt_hash_lock_addr(hash));
|
|
ip_rt_put(rt);
|
|
while ((aux = rcu_dereference_protected(*rthp,
|
|
lockdep_is_held(rt_hash_lock_addr(hash)))) != NULL) {
|
|
if (aux == rt || rt_is_expired(aux)) {
|
|
*rthp = aux->dst.rt_next;
|
|
rt_free(aux);
|
|
continue;
|
|
}
|
|
rthp = &aux->dst.rt_next;
|
|
}
|
|
spin_unlock_bh(rt_hash_lock_addr(hash));
|
|
}
|
|
|
|
/* called in rcu_read_lock() section */
|
|
void ip_rt_redirect(__be32 old_gw, __be32 daddr, __be32 new_gw,
|
|
__be32 saddr, struct net_device *dev)
|
|
{
|
|
int i, k;
|
|
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
|
struct rtable *rth;
|
|
struct rtable __rcu **rthp;
|
|
__be32 skeys[2] = { saddr, 0 };
|
|
int ikeys[2] = { dev->ifindex, 0 };
|
|
struct netevent_redirect netevent;
|
|
struct net *net;
|
|
|
|
if (!in_dev)
|
|
return;
|
|
|
|
net = dev_net(dev);
|
|
if (new_gw == old_gw || !IN_DEV_RX_REDIRECTS(in_dev) ||
|
|
ipv4_is_multicast(new_gw) || ipv4_is_lbcast(new_gw) ||
|
|
ipv4_is_zeronet(new_gw))
|
|
goto reject_redirect;
|
|
|
|
if (!rt_caching(net))
|
|
goto reject_redirect;
|
|
|
|
if (!IN_DEV_SHARED_MEDIA(in_dev)) {
|
|
if (!inet_addr_onlink(in_dev, new_gw, old_gw))
|
|
goto reject_redirect;
|
|
if (IN_DEV_SEC_REDIRECTS(in_dev) && ip_fib_check_default(new_gw, dev))
|
|
goto reject_redirect;
|
|
} else {
|
|
if (inet_addr_type(net, new_gw) != RTN_UNICAST)
|
|
goto reject_redirect;
|
|
}
|
|
|
|
for (i = 0; i < 2; i++) {
|
|
for (k = 0; k < 2; k++) {
|
|
unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
|
|
rt_genid(net));
|
|
|
|
rthp = &rt_hash_table[hash].chain;
|
|
|
|
while ((rth = rcu_dereference(*rthp)) != NULL) {
|
|
struct rtable *rt;
|
|
|
|
if (rth->fl.fl4_dst != daddr ||
|
|
rth->fl.fl4_src != skeys[i] ||
|
|
rth->fl.oif != ikeys[k] ||
|
|
rt_is_input_route(rth) ||
|
|
rt_is_expired(rth) ||
|
|
!net_eq(dev_net(rth->dst.dev), net)) {
|
|
rthp = &rth->dst.rt_next;
|
|
continue;
|
|
}
|
|
|
|
if (rth->rt_dst != daddr ||
|
|
rth->rt_src != saddr ||
|
|
rth->dst.error ||
|
|
rth->rt_gateway != old_gw ||
|
|
rth->dst.dev != dev)
|
|
break;
|
|
|
|
dst_hold(&rth->dst);
|
|
|
|
rt = dst_alloc(&ipv4_dst_ops);
|
|
if (rt == NULL) {
|
|
ip_rt_put(rth);
|
|
return;
|
|
}
|
|
|
|
/* Copy all the information. */
|
|
*rt = *rth;
|
|
rt->dst.__use = 1;
|
|
atomic_set(&rt->dst.__refcnt, 1);
|
|
rt->dst.child = NULL;
|
|
if (rt->dst.dev)
|
|
dev_hold(rt->dst.dev);
|
|
rt->dst.obsolete = -1;
|
|
rt->dst.lastuse = jiffies;
|
|
rt->dst.path = &rt->dst;
|
|
rt->dst.neighbour = NULL;
|
|
rt->dst.hh = NULL;
|
|
#ifdef CONFIG_XFRM
|
|
rt->dst.xfrm = NULL;
|
|
#endif
|
|
rt->rt_genid = rt_genid(net);
|
|
rt->rt_flags |= RTCF_REDIRECTED;
|
|
|
|
/* Gateway is different ... */
|
|
rt->rt_gateway = new_gw;
|
|
|
|
/* Redirect received -> path was valid */
|
|
dst_confirm(&rth->dst);
|
|
|
|
if (rt->peer)
|
|
atomic_inc(&rt->peer->refcnt);
|
|
|
|
if (arp_bind_neighbour(&rt->dst) ||
|
|
!(rt->dst.neighbour->nud_state &
|
|
NUD_VALID)) {
|
|
if (rt->dst.neighbour)
|
|
neigh_event_send(rt->dst.neighbour, NULL);
|
|
ip_rt_put(rth);
|
|
rt_drop(rt);
|
|
goto do_next;
|
|
}
|
|
|
|
netevent.old = &rth->dst;
|
|
netevent.new = &rt->dst;
|
|
call_netevent_notifiers(NETEVENT_REDIRECT,
|
|
&netevent);
|
|
|
|
rt_del(hash, rth);
|
|
if (!rt_intern_hash(hash, rt, &rt, NULL, rt->fl.oif))
|
|
ip_rt_put(rt);
|
|
goto do_next;
|
|
}
|
|
do_next:
|
|
;
|
|
}
|
|
}
|
|
return;
|
|
|
|
reject_redirect:
|
|
#ifdef CONFIG_IP_ROUTE_VERBOSE
|
|
if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
|
|
printk(KERN_INFO "Redirect from %pI4 on %s about %pI4 ignored.\n"
|
|
" Advised path = %pI4 -> %pI4\n",
|
|
&old_gw, dev->name, &new_gw,
|
|
&saddr, &daddr);
|
|
#endif
|
|
;
|
|
}
|
|
|
|
static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst)
|
|
{
|
|
struct rtable *rt = (struct rtable *)dst;
|
|
struct dst_entry *ret = dst;
|
|
|
|
if (rt) {
|
|
if (dst->obsolete > 0) {
|
|
ip_rt_put(rt);
|
|
ret = NULL;
|
|
} else if ((rt->rt_flags & RTCF_REDIRECTED) ||
|
|
(rt->dst.expires &&
|
|
time_after_eq(jiffies, rt->dst.expires))) {
|
|
unsigned hash = rt_hash(rt->fl.fl4_dst, rt->fl.fl4_src,
|
|
rt->fl.oif,
|
|
rt_genid(dev_net(dst->dev)));
|
|
#if RT_CACHE_DEBUG >= 1
|
|
printk(KERN_DEBUG "ipv4_negative_advice: redirect to %pI4/%02x dropped\n",
|
|
&rt->rt_dst, rt->fl.fl4_tos);
|
|
#endif
|
|
rt_del(hash, rt);
|
|
ret = NULL;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Algorithm:
|
|
* 1. The first ip_rt_redirect_number redirects are sent
|
|
* with exponential backoff, then we stop sending them at all,
|
|
* assuming that the host ignores our redirects.
|
|
* 2. If we did not see packets requiring redirects
|
|
* during ip_rt_redirect_silence, we assume that the host
|
|
* forgot redirected route and start to send redirects again.
|
|
*
|
|
* This algorithm is much cheaper and more intelligent than dumb load limiting
|
|
* in icmp.c.
|
|
*
|
|
* NOTE. Do not forget to inhibit load limiting for redirects (redundant)
|
|
* and "frag. need" (breaks PMTU discovery) in icmp.c.
|
|
*/
|
|
|
|
void ip_rt_send_redirect(struct sk_buff *skb)
|
|
{
|
|
struct rtable *rt = skb_rtable(skb);
|
|
struct in_device *in_dev;
|
|
int log_martians;
|
|
|
|
rcu_read_lock();
|
|
in_dev = __in_dev_get_rcu(rt->dst.dev);
|
|
if (!in_dev || !IN_DEV_TX_REDIRECTS(in_dev)) {
|
|
rcu_read_unlock();
|
|
return;
|
|
}
|
|
log_martians = IN_DEV_LOG_MARTIANS(in_dev);
|
|
rcu_read_unlock();
|
|
|
|
/* No redirected packets during ip_rt_redirect_silence;
|
|
* reset the algorithm.
|
|
*/
|
|
if (time_after(jiffies, rt->dst.rate_last + ip_rt_redirect_silence))
|
|
rt->dst.rate_tokens = 0;
|
|
|
|
/* Too many ignored redirects; do not send anything
|
|
* set dst.rate_last to the last seen redirected packet.
|
|
*/
|
|
if (rt->dst.rate_tokens >= ip_rt_redirect_number) {
|
|
rt->dst.rate_last = jiffies;
|
|
return;
|
|
}
|
|
|
|
/* Check for load limit; set rate_last to the latest sent
|
|
* redirect.
|
|
*/
|
|
if (rt->dst.rate_tokens == 0 ||
|
|
time_after(jiffies,
|
|
(rt->dst.rate_last +
|
|
(ip_rt_redirect_load << rt->dst.rate_tokens)))) {
|
|
icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
|
|
rt->dst.rate_last = jiffies;
|
|
++rt->dst.rate_tokens;
|
|
#ifdef CONFIG_IP_ROUTE_VERBOSE
|
|
if (log_martians &&
|
|
rt->dst.rate_tokens == ip_rt_redirect_number &&
|
|
net_ratelimit())
|
|
printk(KERN_WARNING "host %pI4/if%d ignores redirects for %pI4 to %pI4.\n",
|
|
&rt->rt_src, rt->rt_iif,
|
|
&rt->rt_dst, &rt->rt_gateway);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
static int ip_error(struct sk_buff *skb)
|
|
{
|
|
struct rtable *rt = skb_rtable(skb);
|
|
unsigned long now;
|
|
int code;
|
|
|
|
switch (rt->dst.error) {
|
|
case EINVAL:
|
|
default:
|
|
goto out;
|
|
case EHOSTUNREACH:
|
|
code = ICMP_HOST_UNREACH;
|
|
break;
|
|
case ENETUNREACH:
|
|
code = ICMP_NET_UNREACH;
|
|
IP_INC_STATS_BH(dev_net(rt->dst.dev),
|
|
IPSTATS_MIB_INNOROUTES);
|
|
break;
|
|
case EACCES:
|
|
code = ICMP_PKT_FILTERED;
|
|
break;
|
|
}
|
|
|
|
now = jiffies;
|
|
rt->dst.rate_tokens += now - rt->dst.rate_last;
|
|
if (rt->dst.rate_tokens > ip_rt_error_burst)
|
|
rt->dst.rate_tokens = ip_rt_error_burst;
|
|
rt->dst.rate_last = now;
|
|
if (rt->dst.rate_tokens >= ip_rt_error_cost) {
|
|
rt->dst.rate_tokens -= ip_rt_error_cost;
|
|
icmp_send(skb, ICMP_DEST_UNREACH, code, 0);
|
|
}
|
|
|
|
out: kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* The last two values are not from the RFC but
|
|
* are needed for AMPRnet AX.25 paths.
|
|
*/
|
|
|
|
static const unsigned short mtu_plateau[] =
|
|
{32000, 17914, 8166, 4352, 2002, 1492, 576, 296, 216, 128 };
|
|
|
|
static inline unsigned short guess_mtu(unsigned short old_mtu)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < ARRAY_SIZE(mtu_plateau); i++)
|
|
if (old_mtu > mtu_plateau[i])
|
|
return mtu_plateau[i];
|
|
return 68;
|
|
}
|
|
|
|
unsigned short ip_rt_frag_needed(struct net *net, struct iphdr *iph,
|
|
unsigned short new_mtu,
|
|
struct net_device *dev)
|
|
{
|
|
int i, k;
|
|
unsigned short old_mtu = ntohs(iph->tot_len);
|
|
struct rtable *rth;
|
|
int ikeys[2] = { dev->ifindex, 0 };
|
|
__be32 skeys[2] = { iph->saddr, 0, };
|
|
__be32 daddr = iph->daddr;
|
|
unsigned short est_mtu = 0;
|
|
|
|
for (k = 0; k < 2; k++) {
|
|
for (i = 0; i < 2; i++) {
|
|
unsigned hash = rt_hash(daddr, skeys[i], ikeys[k],
|
|
rt_genid(net));
|
|
|
|
rcu_read_lock();
|
|
for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
|
|
rth = rcu_dereference(rth->dst.rt_next)) {
|
|
unsigned short mtu = new_mtu;
|
|
|
|
if (rth->fl.fl4_dst != daddr ||
|
|
rth->fl.fl4_src != skeys[i] ||
|
|
rth->rt_dst != daddr ||
|
|
rth->rt_src != iph->saddr ||
|
|
rth->fl.oif != ikeys[k] ||
|
|
rt_is_input_route(rth) ||
|
|
dst_metric_locked(&rth->dst, RTAX_MTU) ||
|
|
!net_eq(dev_net(rth->dst.dev), net) ||
|
|
rt_is_expired(rth))
|
|
continue;
|
|
|
|
if (new_mtu < 68 || new_mtu >= old_mtu) {
|
|
|
|
/* BSD 4.2 compatibility hack :-( */
|
|
if (mtu == 0 &&
|
|
old_mtu >= dst_mtu(&rth->dst) &&
|
|
old_mtu >= 68 + (iph->ihl << 2))
|
|
old_mtu -= iph->ihl << 2;
|
|
|
|
mtu = guess_mtu(old_mtu);
|
|
}
|
|
if (mtu <= dst_mtu(&rth->dst)) {
|
|
if (mtu < dst_mtu(&rth->dst)) {
|
|
dst_confirm(&rth->dst);
|
|
if (mtu < ip_rt_min_pmtu) {
|
|
u32 lock = dst_metric(&rth->dst,
|
|
RTAX_LOCK);
|
|
mtu = ip_rt_min_pmtu;
|
|
lock |= (1 << RTAX_MTU);
|
|
dst_metric_set(&rth->dst, RTAX_LOCK,
|
|
lock);
|
|
}
|
|
dst_metric_set(&rth->dst, RTAX_MTU, mtu);
|
|
dst_set_expires(&rth->dst,
|
|
ip_rt_mtu_expires);
|
|
}
|
|
est_mtu = mtu;
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
}
|
|
return est_mtu ? : new_mtu;
|
|
}
|
|
|
|
static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
|
|
{
|
|
if (dst_mtu(dst) > mtu && mtu >= 68 &&
|
|
!(dst_metric_locked(dst, RTAX_MTU))) {
|
|
if (mtu < ip_rt_min_pmtu) {
|
|
u32 lock = dst_metric(dst, RTAX_LOCK);
|
|
mtu = ip_rt_min_pmtu;
|
|
dst_metric_set(dst, RTAX_LOCK, lock | (1 << RTAX_MTU));
|
|
}
|
|
dst_metric_set(dst, RTAX_MTU, mtu);
|
|
dst_set_expires(dst, ip_rt_mtu_expires);
|
|
call_netevent_notifiers(NETEVENT_PMTU_UPDATE, dst);
|
|
}
|
|
}
|
|
|
|
static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
|
|
{
|
|
if (rt_is_expired((struct rtable *)dst))
|
|
return NULL;
|
|
return dst;
|
|
}
|
|
|
|
static void ipv4_dst_destroy(struct dst_entry *dst)
|
|
{
|
|
struct rtable *rt = (struct rtable *) dst;
|
|
struct inet_peer *peer = rt->peer;
|
|
|
|
if (peer) {
|
|
rt->peer = NULL;
|
|
inet_putpeer(peer);
|
|
}
|
|
}
|
|
|
|
|
|
static void ipv4_link_failure(struct sk_buff *skb)
|
|
{
|
|
struct rtable *rt;
|
|
|
|
icmp_send(skb, ICMP_DEST_UNREACH, ICMP_HOST_UNREACH, 0);
|
|
|
|
rt = skb_rtable(skb);
|
|
if (rt)
|
|
dst_set_expires(&rt->dst, 0);
|
|
}
|
|
|
|
static int ip_rt_bug(struct sk_buff *skb)
|
|
{
|
|
printk(KERN_DEBUG "ip_rt_bug: %pI4 -> %pI4, %s\n",
|
|
&ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
|
|
skb->dev ? skb->dev->name : "?");
|
|
kfree_skb(skb);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
We do not cache source address of outgoing interface,
|
|
because it is used only by IP RR, TS and SRR options,
|
|
so that it out of fast path.
|
|
|
|
BTW remember: "addr" is allowed to be not aligned
|
|
in IP options!
|
|
*/
|
|
|
|
void ip_rt_get_source(u8 *addr, struct rtable *rt)
|
|
{
|
|
__be32 src;
|
|
struct fib_result res;
|
|
|
|
if (rt_is_output_route(rt))
|
|
src = rt->rt_src;
|
|
else {
|
|
rcu_read_lock();
|
|
if (fib_lookup(dev_net(rt->dst.dev), &rt->fl, &res) == 0)
|
|
src = FIB_RES_PREFSRC(res);
|
|
else
|
|
src = inet_select_addr(rt->dst.dev, rt->rt_gateway,
|
|
RT_SCOPE_UNIVERSE);
|
|
rcu_read_unlock();
|
|
}
|
|
memcpy(addr, &src, 4);
|
|
}
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
static void set_class_tag(struct rtable *rt, u32 tag)
|
|
{
|
|
if (!(rt->dst.tclassid & 0xFFFF))
|
|
rt->dst.tclassid |= tag & 0xFFFF;
|
|
if (!(rt->dst.tclassid & 0xFFFF0000))
|
|
rt->dst.tclassid |= tag & 0xFFFF0000;
|
|
}
|
|
#endif
|
|
|
|
static unsigned int ipv4_default_advmss(const struct dst_entry *dst)
|
|
{
|
|
unsigned int advmss = dst_metric_raw(dst, RTAX_ADVMSS);
|
|
|
|
if (advmss == 0) {
|
|
advmss = max_t(unsigned int, dst->dev->mtu - 40,
|
|
ip_rt_min_advmss);
|
|
if (advmss > 65535 - 40)
|
|
advmss = 65535 - 40;
|
|
}
|
|
return advmss;
|
|
}
|
|
|
|
static unsigned int ipv4_default_mtu(const struct dst_entry *dst)
|
|
{
|
|
unsigned int mtu = dst->dev->mtu;
|
|
|
|
if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
|
|
const struct rtable *rt = (const struct rtable *) dst;
|
|
|
|
if (rt->rt_gateway != rt->rt_dst && mtu > 576)
|
|
mtu = 576;
|
|
}
|
|
|
|
if (mtu > IP_MAX_MTU)
|
|
mtu = IP_MAX_MTU;
|
|
|
|
return mtu;
|
|
}
|
|
|
|
static void rt_set_nexthop(struct rtable *rt, struct fib_result *res, u32 itag)
|
|
{
|
|
struct dst_entry *dst = &rt->dst;
|
|
struct fib_info *fi = res->fi;
|
|
|
|
if (fi) {
|
|
if (FIB_RES_GW(*res) &&
|
|
FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
|
|
rt->rt_gateway = FIB_RES_GW(*res);
|
|
dst_import_metrics(dst, fi->fib_metrics);
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
dst->tclassid = FIB_RES_NH(*res).nh_tclassid;
|
|
#endif
|
|
}
|
|
|
|
if (dst_mtu(dst) > IP_MAX_MTU)
|
|
dst_metric_set(dst, RTAX_MTU, IP_MAX_MTU);
|
|
if (dst_metric_raw(dst, RTAX_ADVMSS) > 65535 - 40)
|
|
dst_metric_set(dst, RTAX_ADVMSS, 65535 - 40);
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
#ifdef CONFIG_IP_MULTIPLE_TABLES
|
|
set_class_tag(rt, fib_rules_tclass(res));
|
|
#endif
|
|
set_class_tag(rt, itag);
|
|
#endif
|
|
rt->rt_type = res->type;
|
|
}
|
|
|
|
/* called in rcu_read_lock() section */
|
|
static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr,
|
|
u8 tos, struct net_device *dev, int our)
|
|
{
|
|
unsigned int hash;
|
|
struct rtable *rth;
|
|
__be32 spec_dst;
|
|
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
|
u32 itag = 0;
|
|
int err;
|
|
|
|
/* Primary sanity checks. */
|
|
|
|
if (in_dev == NULL)
|
|
return -EINVAL;
|
|
|
|
if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
|
|
ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP))
|
|
goto e_inval;
|
|
|
|
if (ipv4_is_zeronet(saddr)) {
|
|
if (!ipv4_is_local_multicast(daddr))
|
|
goto e_inval;
|
|
spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
|
|
} else {
|
|
err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
|
|
&itag, 0);
|
|
if (err < 0)
|
|
goto e_err;
|
|
}
|
|
rth = dst_alloc(&ipv4_dst_ops);
|
|
if (!rth)
|
|
goto e_nobufs;
|
|
|
|
rth->dst.output = ip_rt_bug;
|
|
rth->dst.obsolete = -1;
|
|
|
|
atomic_set(&rth->dst.__refcnt, 1);
|
|
rth->dst.flags= DST_HOST;
|
|
if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
|
|
rth->dst.flags |= DST_NOPOLICY;
|
|
rth->fl.fl4_dst = daddr;
|
|
rth->rt_dst = daddr;
|
|
rth->fl.fl4_tos = tos;
|
|
rth->fl.mark = skb->mark;
|
|
rth->fl.fl4_src = saddr;
|
|
rth->rt_src = saddr;
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
rth->dst.tclassid = itag;
|
|
#endif
|
|
rth->rt_iif =
|
|
rth->fl.iif = dev->ifindex;
|
|
rth->dst.dev = init_net.loopback_dev;
|
|
dev_hold(rth->dst.dev);
|
|
rth->fl.oif = 0;
|
|
rth->rt_gateway = daddr;
|
|
rth->rt_spec_dst= spec_dst;
|
|
rth->rt_genid = rt_genid(dev_net(dev));
|
|
rth->rt_flags = RTCF_MULTICAST;
|
|
rth->rt_type = RTN_MULTICAST;
|
|
if (our) {
|
|
rth->dst.input= ip_local_deliver;
|
|
rth->rt_flags |= RTCF_LOCAL;
|
|
}
|
|
|
|
#ifdef CONFIG_IP_MROUTE
|
|
if (!ipv4_is_local_multicast(daddr) && IN_DEV_MFORWARD(in_dev))
|
|
rth->dst.input = ip_mr_input;
|
|
#endif
|
|
RT_CACHE_STAT_INC(in_slow_mc);
|
|
|
|
hash = rt_hash(daddr, saddr, dev->ifindex, rt_genid(dev_net(dev)));
|
|
return rt_intern_hash(hash, rth, NULL, skb, dev->ifindex);
|
|
|
|
e_nobufs:
|
|
return -ENOBUFS;
|
|
e_inval:
|
|
return -EINVAL;
|
|
e_err:
|
|
return err;
|
|
}
|
|
|
|
|
|
static void ip_handle_martian_source(struct net_device *dev,
|
|
struct in_device *in_dev,
|
|
struct sk_buff *skb,
|
|
__be32 daddr,
|
|
__be32 saddr)
|
|
{
|
|
RT_CACHE_STAT_INC(in_martian_src);
|
|
#ifdef CONFIG_IP_ROUTE_VERBOSE
|
|
if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit()) {
|
|
/*
|
|
* RFC1812 recommendation, if source is martian,
|
|
* the only hint is MAC header.
|
|
*/
|
|
printk(KERN_WARNING "martian source %pI4 from %pI4, on dev %s\n",
|
|
&daddr, &saddr, dev->name);
|
|
if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
|
|
int i;
|
|
const unsigned char *p = skb_mac_header(skb);
|
|
printk(KERN_WARNING "ll header: ");
|
|
for (i = 0; i < dev->hard_header_len; i++, p++) {
|
|
printk("%02x", *p);
|
|
if (i < (dev->hard_header_len - 1))
|
|
printk(":");
|
|
}
|
|
printk("\n");
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
/* called in rcu_read_lock() section */
|
|
static int __mkroute_input(struct sk_buff *skb,
|
|
struct fib_result *res,
|
|
struct in_device *in_dev,
|
|
__be32 daddr, __be32 saddr, u32 tos,
|
|
struct rtable **result)
|
|
{
|
|
struct rtable *rth;
|
|
int err;
|
|
struct in_device *out_dev;
|
|
unsigned int flags = 0;
|
|
__be32 spec_dst;
|
|
u32 itag;
|
|
|
|
/* get a working reference to the output device */
|
|
out_dev = __in_dev_get_rcu(FIB_RES_DEV(*res));
|
|
if (out_dev == NULL) {
|
|
if (net_ratelimit())
|
|
printk(KERN_CRIT "Bug in ip_route_input" \
|
|
"_slow(). Please, report\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
|
|
err = fib_validate_source(saddr, daddr, tos, FIB_RES_OIF(*res),
|
|
in_dev->dev, &spec_dst, &itag, skb->mark);
|
|
if (err < 0) {
|
|
ip_handle_martian_source(in_dev->dev, in_dev, skb, daddr,
|
|
saddr);
|
|
|
|
goto cleanup;
|
|
}
|
|
|
|
if (err)
|
|
flags |= RTCF_DIRECTSRC;
|
|
|
|
if (out_dev == in_dev && err &&
|
|
(IN_DEV_SHARED_MEDIA(out_dev) ||
|
|
inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
|
|
flags |= RTCF_DOREDIRECT;
|
|
|
|
if (skb->protocol != htons(ETH_P_IP)) {
|
|
/* Not IP (i.e. ARP). Do not create route, if it is
|
|
* invalid for proxy arp. DNAT routes are always valid.
|
|
*
|
|
* Proxy arp feature have been extended to allow, ARP
|
|
* replies back to the same interface, to support
|
|
* Private VLAN switch technologies. See arp.c.
|
|
*/
|
|
if (out_dev == in_dev &&
|
|
IN_DEV_PROXY_ARP_PVLAN(in_dev) == 0) {
|
|
err = -EINVAL;
|
|
goto cleanup;
|
|
}
|
|
}
|
|
|
|
|
|
rth = dst_alloc(&ipv4_dst_ops);
|
|
if (!rth) {
|
|
err = -ENOBUFS;
|
|
goto cleanup;
|
|
}
|
|
|
|
atomic_set(&rth->dst.__refcnt, 1);
|
|
rth->dst.flags= DST_HOST;
|
|
if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
|
|
rth->dst.flags |= DST_NOPOLICY;
|
|
if (IN_DEV_CONF_GET(out_dev, NOXFRM))
|
|
rth->dst.flags |= DST_NOXFRM;
|
|
rth->fl.fl4_dst = daddr;
|
|
rth->rt_dst = daddr;
|
|
rth->fl.fl4_tos = tos;
|
|
rth->fl.mark = skb->mark;
|
|
rth->fl.fl4_src = saddr;
|
|
rth->rt_src = saddr;
|
|
rth->rt_gateway = daddr;
|
|
rth->rt_iif =
|
|
rth->fl.iif = in_dev->dev->ifindex;
|
|
rth->dst.dev = (out_dev)->dev;
|
|
dev_hold(rth->dst.dev);
|
|
rth->fl.oif = 0;
|
|
rth->rt_spec_dst= spec_dst;
|
|
|
|
rth->dst.obsolete = -1;
|
|
rth->dst.input = ip_forward;
|
|
rth->dst.output = ip_output;
|
|
rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
|
|
|
|
rt_set_nexthop(rth, res, itag);
|
|
|
|
rth->rt_flags = flags;
|
|
|
|
*result = rth;
|
|
err = 0;
|
|
cleanup:
|
|
return err;
|
|
}
|
|
|
|
static int ip_mkroute_input(struct sk_buff *skb,
|
|
struct fib_result *res,
|
|
const struct flowi *fl,
|
|
struct in_device *in_dev,
|
|
__be32 daddr, __be32 saddr, u32 tos)
|
|
{
|
|
struct rtable* rth = NULL;
|
|
int err;
|
|
unsigned hash;
|
|
|
|
#ifdef CONFIG_IP_ROUTE_MULTIPATH
|
|
if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
|
|
fib_select_multipath(fl, res);
|
|
#endif
|
|
|
|
/* create a routing cache entry */
|
|
err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
|
|
if (err)
|
|
return err;
|
|
|
|
/* put it into the cache */
|
|
hash = rt_hash(daddr, saddr, fl->iif,
|
|
rt_genid(dev_net(rth->dst.dev)));
|
|
return rt_intern_hash(hash, rth, NULL, skb, fl->iif);
|
|
}
|
|
|
|
/*
|
|
* NOTE. We drop all the packets that has local source
|
|
* addresses, because every properly looped back packet
|
|
* must have correct destination already attached by output routine.
|
|
*
|
|
* Such approach solves two big problems:
|
|
* 1. Not simplex devices are handled properly.
|
|
* 2. IP spoofing attempts are filtered with 100% of guarantee.
|
|
* called with rcu_read_lock()
|
|
*/
|
|
|
|
static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
|
|
u8 tos, struct net_device *dev)
|
|
{
|
|
struct fib_result res;
|
|
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
|
struct flowi fl = { .fl4_dst = daddr,
|
|
.fl4_src = saddr,
|
|
.fl4_tos = tos,
|
|
.fl4_scope = RT_SCOPE_UNIVERSE,
|
|
.mark = skb->mark,
|
|
.iif = dev->ifindex };
|
|
unsigned flags = 0;
|
|
u32 itag = 0;
|
|
struct rtable * rth;
|
|
unsigned hash;
|
|
__be32 spec_dst;
|
|
int err = -EINVAL;
|
|
struct net * net = dev_net(dev);
|
|
|
|
/* IP on this device is disabled. */
|
|
|
|
if (!in_dev)
|
|
goto out;
|
|
|
|
/* Check for the most weird martians, which can be not detected
|
|
by fib_lookup.
|
|
*/
|
|
|
|
if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) ||
|
|
ipv4_is_loopback(saddr))
|
|
goto martian_source;
|
|
|
|
if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0))
|
|
goto brd_input;
|
|
|
|
/* Accept zero addresses only to limited broadcast;
|
|
* I even do not know to fix it or not. Waiting for complains :-)
|
|
*/
|
|
if (ipv4_is_zeronet(saddr))
|
|
goto martian_source;
|
|
|
|
if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr))
|
|
goto martian_destination;
|
|
|
|
/*
|
|
* Now we are ready to route packet.
|
|
*/
|
|
err = fib_lookup(net, &fl, &res);
|
|
if (err != 0) {
|
|
if (!IN_DEV_FORWARD(in_dev))
|
|
goto e_hostunreach;
|
|
goto no_route;
|
|
}
|
|
|
|
RT_CACHE_STAT_INC(in_slow_tot);
|
|
|
|
if (res.type == RTN_BROADCAST)
|
|
goto brd_input;
|
|
|
|
if (res.type == RTN_LOCAL) {
|
|
err = fib_validate_source(saddr, daddr, tos,
|
|
net->loopback_dev->ifindex,
|
|
dev, &spec_dst, &itag, skb->mark);
|
|
if (err < 0)
|
|
goto martian_source_keep_err;
|
|
if (err)
|
|
flags |= RTCF_DIRECTSRC;
|
|
spec_dst = daddr;
|
|
goto local_input;
|
|
}
|
|
|
|
if (!IN_DEV_FORWARD(in_dev))
|
|
goto e_hostunreach;
|
|
if (res.type != RTN_UNICAST)
|
|
goto martian_destination;
|
|
|
|
err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
|
|
out: return err;
|
|
|
|
brd_input:
|
|
if (skb->protocol != htons(ETH_P_IP))
|
|
goto e_inval;
|
|
|
|
if (ipv4_is_zeronet(saddr))
|
|
spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
|
|
else {
|
|
err = fib_validate_source(saddr, 0, tos, 0, dev, &spec_dst,
|
|
&itag, skb->mark);
|
|
if (err < 0)
|
|
goto martian_source_keep_err;
|
|
if (err)
|
|
flags |= RTCF_DIRECTSRC;
|
|
}
|
|
flags |= RTCF_BROADCAST;
|
|
res.type = RTN_BROADCAST;
|
|
RT_CACHE_STAT_INC(in_brd);
|
|
|
|
local_input:
|
|
rth = dst_alloc(&ipv4_dst_ops);
|
|
if (!rth)
|
|
goto e_nobufs;
|
|
|
|
rth->dst.output= ip_rt_bug;
|
|
rth->dst.obsolete = -1;
|
|
rth->rt_genid = rt_genid(net);
|
|
|
|
atomic_set(&rth->dst.__refcnt, 1);
|
|
rth->dst.flags= DST_HOST;
|
|
if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
|
|
rth->dst.flags |= DST_NOPOLICY;
|
|
rth->fl.fl4_dst = daddr;
|
|
rth->rt_dst = daddr;
|
|
rth->fl.fl4_tos = tos;
|
|
rth->fl.mark = skb->mark;
|
|
rth->fl.fl4_src = saddr;
|
|
rth->rt_src = saddr;
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
rth->dst.tclassid = itag;
|
|
#endif
|
|
rth->rt_iif =
|
|
rth->fl.iif = dev->ifindex;
|
|
rth->dst.dev = net->loopback_dev;
|
|
dev_hold(rth->dst.dev);
|
|
rth->rt_gateway = daddr;
|
|
rth->rt_spec_dst= spec_dst;
|
|
rth->dst.input= ip_local_deliver;
|
|
rth->rt_flags = flags|RTCF_LOCAL;
|
|
if (res.type == RTN_UNREACHABLE) {
|
|
rth->dst.input= ip_error;
|
|
rth->dst.error= -err;
|
|
rth->rt_flags &= ~RTCF_LOCAL;
|
|
}
|
|
rth->rt_type = res.type;
|
|
hash = rt_hash(daddr, saddr, fl.iif, rt_genid(net));
|
|
err = rt_intern_hash(hash, rth, NULL, skb, fl.iif);
|
|
goto out;
|
|
|
|
no_route:
|
|
RT_CACHE_STAT_INC(in_no_route);
|
|
spec_dst = inet_select_addr(dev, 0, RT_SCOPE_UNIVERSE);
|
|
res.type = RTN_UNREACHABLE;
|
|
if (err == -ESRCH)
|
|
err = -ENETUNREACH;
|
|
goto local_input;
|
|
|
|
/*
|
|
* Do not cache martian addresses: they should be logged (RFC1812)
|
|
*/
|
|
martian_destination:
|
|
RT_CACHE_STAT_INC(in_martian_dst);
|
|
#ifdef CONFIG_IP_ROUTE_VERBOSE
|
|
if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
|
|
printk(KERN_WARNING "martian destination %pI4 from %pI4, dev %s\n",
|
|
&daddr, &saddr, dev->name);
|
|
#endif
|
|
|
|
e_hostunreach:
|
|
err = -EHOSTUNREACH;
|
|
goto out;
|
|
|
|
e_inval:
|
|
err = -EINVAL;
|
|
goto out;
|
|
|
|
e_nobufs:
|
|
err = -ENOBUFS;
|
|
goto out;
|
|
|
|
martian_source:
|
|
err = -EINVAL;
|
|
martian_source_keep_err:
|
|
ip_handle_martian_source(dev, in_dev, skb, daddr, saddr);
|
|
goto out;
|
|
}
|
|
|
|
int ip_route_input_common(struct sk_buff *skb, __be32 daddr, __be32 saddr,
|
|
u8 tos, struct net_device *dev, bool noref)
|
|
{
|
|
struct rtable * rth;
|
|
unsigned hash;
|
|
int iif = dev->ifindex;
|
|
struct net *net;
|
|
int res;
|
|
|
|
net = dev_net(dev);
|
|
|
|
rcu_read_lock();
|
|
|
|
if (!rt_caching(net))
|
|
goto skip_cache;
|
|
|
|
tos &= IPTOS_RT_MASK;
|
|
hash = rt_hash(daddr, saddr, iif, rt_genid(net));
|
|
|
|
for (rth = rcu_dereference(rt_hash_table[hash].chain); rth;
|
|
rth = rcu_dereference(rth->dst.rt_next)) {
|
|
if ((((__force u32)rth->fl.fl4_dst ^ (__force u32)daddr) |
|
|
((__force u32)rth->fl.fl4_src ^ (__force u32)saddr) |
|
|
(rth->fl.iif ^ iif) |
|
|
rth->fl.oif |
|
|
(rth->fl.fl4_tos ^ tos)) == 0 &&
|
|
rth->fl.mark == skb->mark &&
|
|
net_eq(dev_net(rth->dst.dev), net) &&
|
|
!rt_is_expired(rth)) {
|
|
if (noref) {
|
|
dst_use_noref(&rth->dst, jiffies);
|
|
skb_dst_set_noref(skb, &rth->dst);
|
|
} else {
|
|
dst_use(&rth->dst, jiffies);
|
|
skb_dst_set(skb, &rth->dst);
|
|
}
|
|
RT_CACHE_STAT_INC(in_hit);
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|
|
RT_CACHE_STAT_INC(in_hlist_search);
|
|
}
|
|
|
|
skip_cache:
|
|
/* Multicast recognition logic is moved from route cache to here.
|
|
The problem was that too many Ethernet cards have broken/missing
|
|
hardware multicast filters :-( As result the host on multicasting
|
|
network acquires a lot of useless route cache entries, sort of
|
|
SDR messages from all the world. Now we try to get rid of them.
|
|
Really, provided software IP multicast filter is organized
|
|
reasonably (at least, hashed), it does not result in a slowdown
|
|
comparing with route cache reject entries.
|
|
Note, that multicast routers are not affected, because
|
|
route cache entry is created eventually.
|
|
*/
|
|
if (ipv4_is_multicast(daddr)) {
|
|
struct in_device *in_dev = __in_dev_get_rcu(dev);
|
|
|
|
if (in_dev) {
|
|
int our = ip_check_mc(in_dev, daddr, saddr,
|
|
ip_hdr(skb)->protocol);
|
|
if (our
|
|
#ifdef CONFIG_IP_MROUTE
|
|
||
|
|
(!ipv4_is_local_multicast(daddr) &&
|
|
IN_DEV_MFORWARD(in_dev))
|
|
#endif
|
|
) {
|
|
int res = ip_route_input_mc(skb, daddr, saddr,
|
|
tos, dev, our);
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
return -EINVAL;
|
|
}
|
|
res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL(ip_route_input_common);
|
|
|
|
/* called with rcu_read_lock() */
|
|
static int __mkroute_output(struct rtable **result,
|
|
struct fib_result *res,
|
|
const struct flowi *fl,
|
|
const struct flowi *oldflp,
|
|
struct net_device *dev_out,
|
|
unsigned flags)
|
|
{
|
|
struct rtable *rth;
|
|
struct in_device *in_dev;
|
|
u32 tos = RT_FL_TOS(oldflp);
|
|
|
|
if (ipv4_is_loopback(fl->fl4_src) && !(dev_out->flags & IFF_LOOPBACK))
|
|
return -EINVAL;
|
|
|
|
if (ipv4_is_lbcast(fl->fl4_dst))
|
|
res->type = RTN_BROADCAST;
|
|
else if (ipv4_is_multicast(fl->fl4_dst))
|
|
res->type = RTN_MULTICAST;
|
|
else if (ipv4_is_zeronet(fl->fl4_dst))
|
|
return -EINVAL;
|
|
|
|
if (dev_out->flags & IFF_LOOPBACK)
|
|
flags |= RTCF_LOCAL;
|
|
|
|
in_dev = __in_dev_get_rcu(dev_out);
|
|
if (!in_dev)
|
|
return -EINVAL;
|
|
|
|
if (res->type == RTN_BROADCAST) {
|
|
flags |= RTCF_BROADCAST | RTCF_LOCAL;
|
|
res->fi = NULL;
|
|
} else if (res->type == RTN_MULTICAST) {
|
|
flags |= RTCF_MULTICAST | RTCF_LOCAL;
|
|
if (!ip_check_mc(in_dev, oldflp->fl4_dst, oldflp->fl4_src,
|
|
oldflp->proto))
|
|
flags &= ~RTCF_LOCAL;
|
|
/* If multicast route do not exist use
|
|
* default one, but do not gateway in this case.
|
|
* Yes, it is hack.
|
|
*/
|
|
if (res->fi && res->prefixlen < 4)
|
|
res->fi = NULL;
|
|
}
|
|
|
|
|
|
rth = dst_alloc(&ipv4_dst_ops);
|
|
if (!rth)
|
|
return -ENOBUFS;
|
|
|
|
atomic_set(&rth->dst.__refcnt, 1);
|
|
rth->dst.flags= DST_HOST;
|
|
if (IN_DEV_CONF_GET(in_dev, NOXFRM))
|
|
rth->dst.flags |= DST_NOXFRM;
|
|
if (IN_DEV_CONF_GET(in_dev, NOPOLICY))
|
|
rth->dst.flags |= DST_NOPOLICY;
|
|
|
|
rth->fl.fl4_dst = oldflp->fl4_dst;
|
|
rth->fl.fl4_tos = tos;
|
|
rth->fl.fl4_src = oldflp->fl4_src;
|
|
rth->fl.oif = oldflp->oif;
|
|
rth->fl.mark = oldflp->mark;
|
|
rth->rt_dst = fl->fl4_dst;
|
|
rth->rt_src = fl->fl4_src;
|
|
rth->rt_iif = oldflp->oif ? : dev_out->ifindex;
|
|
/* get references to the devices that are to be hold by the routing
|
|
cache entry */
|
|
rth->dst.dev = dev_out;
|
|
dev_hold(dev_out);
|
|
rth->rt_gateway = fl->fl4_dst;
|
|
rth->rt_spec_dst= fl->fl4_src;
|
|
|
|
rth->dst.output=ip_output;
|
|
rth->dst.obsolete = -1;
|
|
rth->rt_genid = rt_genid(dev_net(dev_out));
|
|
|
|
RT_CACHE_STAT_INC(out_slow_tot);
|
|
|
|
if (flags & RTCF_LOCAL) {
|
|
rth->dst.input = ip_local_deliver;
|
|
rth->rt_spec_dst = fl->fl4_dst;
|
|
}
|
|
if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
|
|
rth->rt_spec_dst = fl->fl4_src;
|
|
if (flags & RTCF_LOCAL &&
|
|
!(dev_out->flags & IFF_LOOPBACK)) {
|
|
rth->dst.output = ip_mc_output;
|
|
RT_CACHE_STAT_INC(out_slow_mc);
|
|
}
|
|
#ifdef CONFIG_IP_MROUTE
|
|
if (res->type == RTN_MULTICAST) {
|
|
if (IN_DEV_MFORWARD(in_dev) &&
|
|
!ipv4_is_local_multicast(oldflp->fl4_dst)) {
|
|
rth->dst.input = ip_mr_input;
|
|
rth->dst.output = ip_mc_output;
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
rt_set_nexthop(rth, res, 0);
|
|
|
|
rth->rt_flags = flags;
|
|
*result = rth;
|
|
return 0;
|
|
}
|
|
|
|
/* called with rcu_read_lock() */
|
|
static int ip_mkroute_output(struct rtable **rp,
|
|
struct fib_result *res,
|
|
const struct flowi *fl,
|
|
const struct flowi *oldflp,
|
|
struct net_device *dev_out,
|
|
unsigned flags)
|
|
{
|
|
struct rtable *rth = NULL;
|
|
int err = __mkroute_output(&rth, res, fl, oldflp, dev_out, flags);
|
|
unsigned hash;
|
|
if (err == 0) {
|
|
hash = rt_hash(oldflp->fl4_dst, oldflp->fl4_src, oldflp->oif,
|
|
rt_genid(dev_net(dev_out)));
|
|
err = rt_intern_hash(hash, rth, rp, NULL, oldflp->oif);
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Major route resolver routine.
|
|
* called with rcu_read_lock();
|
|
*/
|
|
|
|
static int ip_route_output_slow(struct net *net, struct rtable **rp,
|
|
const struct flowi *oldflp)
|
|
{
|
|
u32 tos = RT_FL_TOS(oldflp);
|
|
struct flowi fl = { .fl4_dst = oldflp->fl4_dst,
|
|
.fl4_src = oldflp->fl4_src,
|
|
.fl4_tos = tos & IPTOS_RT_MASK,
|
|
.fl4_scope = ((tos & RTO_ONLINK) ?
|
|
RT_SCOPE_LINK : RT_SCOPE_UNIVERSE),
|
|
.mark = oldflp->mark,
|
|
.iif = net->loopback_dev->ifindex,
|
|
.oif = oldflp->oif };
|
|
struct fib_result res;
|
|
unsigned int flags = 0;
|
|
struct net_device *dev_out = NULL;
|
|
int err;
|
|
|
|
|
|
res.fi = NULL;
|
|
#ifdef CONFIG_IP_MULTIPLE_TABLES
|
|
res.r = NULL;
|
|
#endif
|
|
|
|
if (oldflp->fl4_src) {
|
|
err = -EINVAL;
|
|
if (ipv4_is_multicast(oldflp->fl4_src) ||
|
|
ipv4_is_lbcast(oldflp->fl4_src) ||
|
|
ipv4_is_zeronet(oldflp->fl4_src))
|
|
goto out;
|
|
|
|
/* I removed check for oif == dev_out->oif here.
|
|
It was wrong for two reasons:
|
|
1. ip_dev_find(net, saddr) can return wrong iface, if saddr
|
|
is assigned to multiple interfaces.
|
|
2. Moreover, we are allowed to send packets with saddr
|
|
of another iface. --ANK
|
|
*/
|
|
|
|
if (oldflp->oif == 0 &&
|
|
(ipv4_is_multicast(oldflp->fl4_dst) ||
|
|
ipv4_is_lbcast(oldflp->fl4_dst))) {
|
|
/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
|
|
dev_out = __ip_dev_find(net, oldflp->fl4_src, false);
|
|
if (dev_out == NULL)
|
|
goto out;
|
|
|
|
/* Special hack: user can direct multicasts
|
|
and limited broadcast via necessary interface
|
|
without fiddling with IP_MULTICAST_IF or IP_PKTINFO.
|
|
This hack is not just for fun, it allows
|
|
vic,vat and friends to work.
|
|
They bind socket to loopback, set ttl to zero
|
|
and expect that it will work.
|
|
From the viewpoint of routing cache they are broken,
|
|
because we are not allowed to build multicast path
|
|
with loopback source addr (look, routing cache
|
|
cannot know, that ttl is zero, so that packet
|
|
will not leave this host and route is valid).
|
|
Luckily, this hack is good workaround.
|
|
*/
|
|
|
|
fl.oif = dev_out->ifindex;
|
|
goto make_route;
|
|
}
|
|
|
|
if (!(oldflp->flags & FLOWI_FLAG_ANYSRC)) {
|
|
/* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
|
|
if (!__ip_dev_find(net, oldflp->fl4_src, false))
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
|
|
if (oldflp->oif) {
|
|
dev_out = dev_get_by_index_rcu(net, oldflp->oif);
|
|
err = -ENODEV;
|
|
if (dev_out == NULL)
|
|
goto out;
|
|
|
|
/* RACE: Check return value of inet_select_addr instead. */
|
|
if (!(dev_out->flags & IFF_UP) || !__in_dev_get_rcu(dev_out)) {
|
|
err = -ENETUNREACH;
|
|
goto out;
|
|
}
|
|
if (ipv4_is_local_multicast(oldflp->fl4_dst) ||
|
|
ipv4_is_lbcast(oldflp->fl4_dst)) {
|
|
if (!fl.fl4_src)
|
|
fl.fl4_src = inet_select_addr(dev_out, 0,
|
|
RT_SCOPE_LINK);
|
|
goto make_route;
|
|
}
|
|
if (!fl.fl4_src) {
|
|
if (ipv4_is_multicast(oldflp->fl4_dst))
|
|
fl.fl4_src = inet_select_addr(dev_out, 0,
|
|
fl.fl4_scope);
|
|
else if (!oldflp->fl4_dst)
|
|
fl.fl4_src = inet_select_addr(dev_out, 0,
|
|
RT_SCOPE_HOST);
|
|
}
|
|
}
|
|
|
|
if (!fl.fl4_dst) {
|
|
fl.fl4_dst = fl.fl4_src;
|
|
if (!fl.fl4_dst)
|
|
fl.fl4_dst = fl.fl4_src = htonl(INADDR_LOOPBACK);
|
|
dev_out = net->loopback_dev;
|
|
fl.oif = net->loopback_dev->ifindex;
|
|
res.type = RTN_LOCAL;
|
|
flags |= RTCF_LOCAL;
|
|
goto make_route;
|
|
}
|
|
|
|
if (fib_lookup(net, &fl, &res)) {
|
|
res.fi = NULL;
|
|
if (oldflp->oif) {
|
|
/* Apparently, routing tables are wrong. Assume,
|
|
that the destination is on link.
|
|
|
|
WHY? DW.
|
|
Because we are allowed to send to iface
|
|
even if it has NO routes and NO assigned
|
|
addresses. When oif is specified, routing
|
|
tables are looked up with only one purpose:
|
|
to catch if destination is gatewayed, rather than
|
|
direct. Moreover, if MSG_DONTROUTE is set,
|
|
we send packet, ignoring both routing tables
|
|
and ifaddr state. --ANK
|
|
|
|
|
|
We could make it even if oif is unknown,
|
|
likely IPv6, but we do not.
|
|
*/
|
|
|
|
if (fl.fl4_src == 0)
|
|
fl.fl4_src = inet_select_addr(dev_out, 0,
|
|
RT_SCOPE_LINK);
|
|
res.type = RTN_UNICAST;
|
|
goto make_route;
|
|
}
|
|
err = -ENETUNREACH;
|
|
goto out;
|
|
}
|
|
|
|
if (res.type == RTN_LOCAL) {
|
|
if (!fl.fl4_src) {
|
|
if (res.fi->fib_prefsrc)
|
|
fl.fl4_src = res.fi->fib_prefsrc;
|
|
else
|
|
fl.fl4_src = fl.fl4_dst;
|
|
}
|
|
dev_out = net->loopback_dev;
|
|
fl.oif = dev_out->ifindex;
|
|
res.fi = NULL;
|
|
flags |= RTCF_LOCAL;
|
|
goto make_route;
|
|
}
|
|
|
|
#ifdef CONFIG_IP_ROUTE_MULTIPATH
|
|
if (res.fi->fib_nhs > 1 && fl.oif == 0)
|
|
fib_select_multipath(&fl, &res);
|
|
else
|
|
#endif
|
|
if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
|
|
fib_select_default(net, &fl, &res);
|
|
|
|
if (!fl.fl4_src)
|
|
fl.fl4_src = FIB_RES_PREFSRC(res);
|
|
|
|
dev_out = FIB_RES_DEV(res);
|
|
fl.oif = dev_out->ifindex;
|
|
|
|
|
|
make_route:
|
|
err = ip_mkroute_output(rp, &res, &fl, oldflp, dev_out, flags);
|
|
|
|
out: return err;
|
|
}
|
|
|
|
int __ip_route_output_key(struct net *net, struct rtable **rp,
|
|
const struct flowi *flp)
|
|
{
|
|
unsigned int hash;
|
|
int res;
|
|
struct rtable *rth;
|
|
|
|
if (!rt_caching(net))
|
|
goto slow_output;
|
|
|
|
hash = rt_hash(flp->fl4_dst, flp->fl4_src, flp->oif, rt_genid(net));
|
|
|
|
rcu_read_lock_bh();
|
|
for (rth = rcu_dereference_bh(rt_hash_table[hash].chain); rth;
|
|
rth = rcu_dereference_bh(rth->dst.rt_next)) {
|
|
if (rth->fl.fl4_dst == flp->fl4_dst &&
|
|
rth->fl.fl4_src == flp->fl4_src &&
|
|
rt_is_output_route(rth) &&
|
|
rth->fl.oif == flp->oif &&
|
|
rth->fl.mark == flp->mark &&
|
|
!((rth->fl.fl4_tos ^ flp->fl4_tos) &
|
|
(IPTOS_RT_MASK | RTO_ONLINK)) &&
|
|
net_eq(dev_net(rth->dst.dev), net) &&
|
|
!rt_is_expired(rth)) {
|
|
dst_use(&rth->dst, jiffies);
|
|
RT_CACHE_STAT_INC(out_hit);
|
|
rcu_read_unlock_bh();
|
|
*rp = rth;
|
|
return 0;
|
|
}
|
|
RT_CACHE_STAT_INC(out_hlist_search);
|
|
}
|
|
rcu_read_unlock_bh();
|
|
|
|
slow_output:
|
|
rcu_read_lock();
|
|
res = ip_route_output_slow(net, rp, flp);
|
|
rcu_read_unlock();
|
|
return res;
|
|
}
|
|
EXPORT_SYMBOL_GPL(__ip_route_output_key);
|
|
|
|
static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
|
|
{
|
|
return NULL;
|
|
}
|
|
|
|
static unsigned int ipv4_blackhole_default_mtu(const struct dst_entry *dst)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
|
|
{
|
|
}
|
|
|
|
static struct dst_ops ipv4_dst_blackhole_ops = {
|
|
.family = AF_INET,
|
|
.protocol = cpu_to_be16(ETH_P_IP),
|
|
.destroy = ipv4_dst_destroy,
|
|
.check = ipv4_blackhole_dst_check,
|
|
.default_mtu = ipv4_blackhole_default_mtu,
|
|
.default_advmss = ipv4_default_advmss,
|
|
.update_pmtu = ipv4_rt_blackhole_update_pmtu,
|
|
};
|
|
|
|
|
|
static int ipv4_dst_blackhole(struct net *net, struct rtable **rp, struct flowi *flp)
|
|
{
|
|
struct rtable *ort = *rp;
|
|
struct rtable *rt = (struct rtable *)
|
|
dst_alloc(&ipv4_dst_blackhole_ops);
|
|
|
|
if (rt) {
|
|
struct dst_entry *new = &rt->dst;
|
|
|
|
atomic_set(&new->__refcnt, 1);
|
|
new->__use = 1;
|
|
new->input = dst_discard;
|
|
new->output = dst_discard;
|
|
dst_copy_metrics(new, &ort->dst);
|
|
|
|
new->dev = ort->dst.dev;
|
|
if (new->dev)
|
|
dev_hold(new->dev);
|
|
|
|
rt->fl = ort->fl;
|
|
|
|
rt->rt_genid = rt_genid(net);
|
|
rt->rt_flags = ort->rt_flags;
|
|
rt->rt_type = ort->rt_type;
|
|
rt->rt_dst = ort->rt_dst;
|
|
rt->rt_src = ort->rt_src;
|
|
rt->rt_iif = ort->rt_iif;
|
|
rt->rt_gateway = ort->rt_gateway;
|
|
rt->rt_spec_dst = ort->rt_spec_dst;
|
|
rt->peer = ort->peer;
|
|
if (rt->peer)
|
|
atomic_inc(&rt->peer->refcnt);
|
|
|
|
dst_free(new);
|
|
}
|
|
|
|
dst_release(&(*rp)->dst);
|
|
*rp = rt;
|
|
return rt ? 0 : -ENOMEM;
|
|
}
|
|
|
|
int ip_route_output_flow(struct net *net, struct rtable **rp, struct flowi *flp,
|
|
struct sock *sk, int flags)
|
|
{
|
|
int err;
|
|
|
|
if ((err = __ip_route_output_key(net, rp, flp)) != 0)
|
|
return err;
|
|
|
|
if (flp->proto) {
|
|
if (!flp->fl4_src)
|
|
flp->fl4_src = (*rp)->rt_src;
|
|
if (!flp->fl4_dst)
|
|
flp->fl4_dst = (*rp)->rt_dst;
|
|
err = __xfrm_lookup(net, (struct dst_entry **)rp, flp, sk,
|
|
flags ? XFRM_LOOKUP_WAIT : 0);
|
|
if (err == -EREMOTE)
|
|
err = ipv4_dst_blackhole(net, rp, flp);
|
|
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL_GPL(ip_route_output_flow);
|
|
|
|
int ip_route_output_key(struct net *net, struct rtable **rp, struct flowi *flp)
|
|
{
|
|
return ip_route_output_flow(net, rp, flp, NULL, 0);
|
|
}
|
|
EXPORT_SYMBOL(ip_route_output_key);
|
|
|
|
static int rt_fill_info(struct net *net,
|
|
struct sk_buff *skb, u32 pid, u32 seq, int event,
|
|
int nowait, unsigned int flags)
|
|
{
|
|
struct rtable *rt = skb_rtable(skb);
|
|
struct rtmsg *r;
|
|
struct nlmsghdr *nlh;
|
|
long expires;
|
|
u32 id = 0, ts = 0, tsage = 0, error;
|
|
|
|
nlh = nlmsg_put(skb, pid, seq, event, sizeof(*r), flags);
|
|
if (nlh == NULL)
|
|
return -EMSGSIZE;
|
|
|
|
r = nlmsg_data(nlh);
|
|
r->rtm_family = AF_INET;
|
|
r->rtm_dst_len = 32;
|
|
r->rtm_src_len = 0;
|
|
r->rtm_tos = rt->fl.fl4_tos;
|
|
r->rtm_table = RT_TABLE_MAIN;
|
|
NLA_PUT_U32(skb, RTA_TABLE, RT_TABLE_MAIN);
|
|
r->rtm_type = rt->rt_type;
|
|
r->rtm_scope = RT_SCOPE_UNIVERSE;
|
|
r->rtm_protocol = RTPROT_UNSPEC;
|
|
r->rtm_flags = (rt->rt_flags & ~0xFFFF) | RTM_F_CLONED;
|
|
if (rt->rt_flags & RTCF_NOTIFY)
|
|
r->rtm_flags |= RTM_F_NOTIFY;
|
|
|
|
NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst);
|
|
|
|
if (rt->fl.fl4_src) {
|
|
r->rtm_src_len = 32;
|
|
NLA_PUT_BE32(skb, RTA_SRC, rt->fl.fl4_src);
|
|
}
|
|
if (rt->dst.dev)
|
|
NLA_PUT_U32(skb, RTA_OIF, rt->dst.dev->ifindex);
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
if (rt->dst.tclassid)
|
|
NLA_PUT_U32(skb, RTA_FLOW, rt->dst.tclassid);
|
|
#endif
|
|
if (rt_is_input_route(rt))
|
|
NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_spec_dst);
|
|
else if (rt->rt_src != rt->fl.fl4_src)
|
|
NLA_PUT_BE32(skb, RTA_PREFSRC, rt->rt_src);
|
|
|
|
if (rt->rt_dst != rt->rt_gateway)
|
|
NLA_PUT_BE32(skb, RTA_GATEWAY, rt->rt_gateway);
|
|
|
|
if (rtnetlink_put_metrics(skb, dst_metrics_ptr(&rt->dst)) < 0)
|
|
goto nla_put_failure;
|
|
|
|
if (rt->fl.mark)
|
|
NLA_PUT_BE32(skb, RTA_MARK, rt->fl.mark);
|
|
|
|
error = rt->dst.error;
|
|
expires = rt->dst.expires ? rt->dst.expires - jiffies : 0;
|
|
if (rt->peer) {
|
|
inet_peer_refcheck(rt->peer);
|
|
id = atomic_read(&rt->peer->ip_id_count) & 0xffff;
|
|
if (rt->peer->tcp_ts_stamp) {
|
|
ts = rt->peer->tcp_ts;
|
|
tsage = get_seconds() - rt->peer->tcp_ts_stamp;
|
|
}
|
|
}
|
|
|
|
if (rt_is_input_route(rt)) {
|
|
#ifdef CONFIG_IP_MROUTE
|
|
__be32 dst = rt->rt_dst;
|
|
|
|
if (ipv4_is_multicast(dst) && !ipv4_is_local_multicast(dst) &&
|
|
IPV4_DEVCONF_ALL(net, MC_FORWARDING)) {
|
|
int err = ipmr_get_route(net, skb, r, nowait);
|
|
if (err <= 0) {
|
|
if (!nowait) {
|
|
if (err == 0)
|
|
return 0;
|
|
goto nla_put_failure;
|
|
} else {
|
|
if (err == -EMSGSIZE)
|
|
goto nla_put_failure;
|
|
error = err;
|
|
}
|
|
}
|
|
} else
|
|
#endif
|
|
NLA_PUT_U32(skb, RTA_IIF, rt->fl.iif);
|
|
}
|
|
|
|
if (rtnl_put_cacheinfo(skb, &rt->dst, id, ts, tsage,
|
|
expires, error) < 0)
|
|
goto nla_put_failure;
|
|
|
|
return nlmsg_end(skb, nlh);
|
|
|
|
nla_put_failure:
|
|
nlmsg_cancel(skb, nlh);
|
|
return -EMSGSIZE;
|
|
}
|
|
|
|
static int inet_rtm_getroute(struct sk_buff *in_skb, struct nlmsghdr* nlh, void *arg)
|
|
{
|
|
struct net *net = sock_net(in_skb->sk);
|
|
struct rtmsg *rtm;
|
|
struct nlattr *tb[RTA_MAX+1];
|
|
struct rtable *rt = NULL;
|
|
__be32 dst = 0;
|
|
__be32 src = 0;
|
|
u32 iif;
|
|
int err;
|
|
int mark;
|
|
struct sk_buff *skb;
|
|
|
|
err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_ipv4_policy);
|
|
if (err < 0)
|
|
goto errout;
|
|
|
|
rtm = nlmsg_data(nlh);
|
|
|
|
skb = alloc_skb(NLMSG_GOODSIZE, GFP_KERNEL);
|
|
if (skb == NULL) {
|
|
err = -ENOBUFS;
|
|
goto errout;
|
|
}
|
|
|
|
/* Reserve room for dummy headers, this skb can pass
|
|
through good chunk of routing engine.
|
|
*/
|
|
skb_reset_mac_header(skb);
|
|
skb_reset_network_header(skb);
|
|
|
|
/* Bugfix: need to give ip_route_input enough of an IP header to not gag. */
|
|
ip_hdr(skb)->protocol = IPPROTO_ICMP;
|
|
skb_reserve(skb, MAX_HEADER + sizeof(struct iphdr));
|
|
|
|
src = tb[RTA_SRC] ? nla_get_be32(tb[RTA_SRC]) : 0;
|
|
dst = tb[RTA_DST] ? nla_get_be32(tb[RTA_DST]) : 0;
|
|
iif = tb[RTA_IIF] ? nla_get_u32(tb[RTA_IIF]) : 0;
|
|
mark = tb[RTA_MARK] ? nla_get_u32(tb[RTA_MARK]) : 0;
|
|
|
|
if (iif) {
|
|
struct net_device *dev;
|
|
|
|
dev = __dev_get_by_index(net, iif);
|
|
if (dev == NULL) {
|
|
err = -ENODEV;
|
|
goto errout_free;
|
|
}
|
|
|
|
skb->protocol = htons(ETH_P_IP);
|
|
skb->dev = dev;
|
|
skb->mark = mark;
|
|
local_bh_disable();
|
|
err = ip_route_input(skb, dst, src, rtm->rtm_tos, dev);
|
|
local_bh_enable();
|
|
|
|
rt = skb_rtable(skb);
|
|
if (err == 0 && rt->dst.error)
|
|
err = -rt->dst.error;
|
|
} else {
|
|
struct flowi fl = {
|
|
.fl4_dst = dst,
|
|
.fl4_src = src,
|
|
.fl4_tos = rtm->rtm_tos,
|
|
.oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
|
|
.mark = mark,
|
|
};
|
|
err = ip_route_output_key(net, &rt, &fl);
|
|
}
|
|
|
|
if (err)
|
|
goto errout_free;
|
|
|
|
skb_dst_set(skb, &rt->dst);
|
|
if (rtm->rtm_flags & RTM_F_NOTIFY)
|
|
rt->rt_flags |= RTCF_NOTIFY;
|
|
|
|
err = rt_fill_info(net, skb, NETLINK_CB(in_skb).pid, nlh->nlmsg_seq,
|
|
RTM_NEWROUTE, 0, 0);
|
|
if (err <= 0)
|
|
goto errout_free;
|
|
|
|
err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).pid);
|
|
errout:
|
|
return err;
|
|
|
|
errout_free:
|
|
kfree_skb(skb);
|
|
goto errout;
|
|
}
|
|
|
|
int ip_rt_dump(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
struct rtable *rt;
|
|
int h, s_h;
|
|
int idx, s_idx;
|
|
struct net *net;
|
|
|
|
net = sock_net(skb->sk);
|
|
|
|
s_h = cb->args[0];
|
|
if (s_h < 0)
|
|
s_h = 0;
|
|
s_idx = idx = cb->args[1];
|
|
for (h = s_h; h <= rt_hash_mask; h++, s_idx = 0) {
|
|
if (!rt_hash_table[h].chain)
|
|
continue;
|
|
rcu_read_lock_bh();
|
|
for (rt = rcu_dereference_bh(rt_hash_table[h].chain), idx = 0; rt;
|
|
rt = rcu_dereference_bh(rt->dst.rt_next), idx++) {
|
|
if (!net_eq(dev_net(rt->dst.dev), net) || idx < s_idx)
|
|
continue;
|
|
if (rt_is_expired(rt))
|
|
continue;
|
|
skb_dst_set_noref(skb, &rt->dst);
|
|
if (rt_fill_info(net, skb, NETLINK_CB(cb->skb).pid,
|
|
cb->nlh->nlmsg_seq, RTM_NEWROUTE,
|
|
1, NLM_F_MULTI) <= 0) {
|
|
skb_dst_drop(skb);
|
|
rcu_read_unlock_bh();
|
|
goto done;
|
|
}
|
|
skb_dst_drop(skb);
|
|
}
|
|
rcu_read_unlock_bh();
|
|
}
|
|
|
|
done:
|
|
cb->args[0] = h;
|
|
cb->args[1] = idx;
|
|
return skb->len;
|
|
}
|
|
|
|
void ip_rt_multicast_event(struct in_device *in_dev)
|
|
{
|
|
rt_cache_flush(dev_net(in_dev->dev), 0);
|
|
}
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
static int ipv4_sysctl_rtcache_flush(ctl_table *__ctl, int write,
|
|
void __user *buffer,
|
|
size_t *lenp, loff_t *ppos)
|
|
{
|
|
if (write) {
|
|
int flush_delay;
|
|
ctl_table ctl;
|
|
struct net *net;
|
|
|
|
memcpy(&ctl, __ctl, sizeof(ctl));
|
|
ctl.data = &flush_delay;
|
|
proc_dointvec(&ctl, write, buffer, lenp, ppos);
|
|
|
|
net = (struct net *)__ctl->extra1;
|
|
rt_cache_flush(net, flush_delay);
|
|
return 0;
|
|
}
|
|
|
|
return -EINVAL;
|
|
}
|
|
|
|
static ctl_table ipv4_route_table[] = {
|
|
{
|
|
.procname = "gc_thresh",
|
|
.data = &ipv4_dst_ops.gc_thresh,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "max_size",
|
|
.data = &ip_rt_max_size,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
/* Deprecated. Use gc_min_interval_ms */
|
|
|
|
.procname = "gc_min_interval",
|
|
.data = &ip_rt_gc_min_interval,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{
|
|
.procname = "gc_min_interval_ms",
|
|
.data = &ip_rt_gc_min_interval,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_ms_jiffies,
|
|
},
|
|
{
|
|
.procname = "gc_timeout",
|
|
.data = &ip_rt_gc_timeout,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{
|
|
.procname = "gc_interval",
|
|
.data = &ip_rt_gc_interval,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{
|
|
.procname = "redirect_load",
|
|
.data = &ip_rt_redirect_load,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "redirect_number",
|
|
.data = &ip_rt_redirect_number,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "redirect_silence",
|
|
.data = &ip_rt_redirect_silence,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "error_cost",
|
|
.data = &ip_rt_error_cost,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "error_burst",
|
|
.data = &ip_rt_error_burst,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "gc_elasticity",
|
|
.data = &ip_rt_gc_elasticity,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "mtu_expires",
|
|
.data = &ip_rt_mtu_expires,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec_jiffies,
|
|
},
|
|
{
|
|
.procname = "min_pmtu",
|
|
.data = &ip_rt_min_pmtu,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{
|
|
.procname = "min_adv_mss",
|
|
.data = &ip_rt_min_advmss,
|
|
.maxlen = sizeof(int),
|
|
.mode = 0644,
|
|
.proc_handler = proc_dointvec,
|
|
},
|
|
{ }
|
|
};
|
|
|
|
static struct ctl_table empty[1];
|
|
|
|
static struct ctl_table ipv4_skeleton[] =
|
|
{
|
|
{ .procname = "route",
|
|
.mode = 0555, .child = ipv4_route_table},
|
|
{ .procname = "neigh",
|
|
.mode = 0555, .child = empty},
|
|
{ }
|
|
};
|
|
|
|
static __net_initdata struct ctl_path ipv4_path[] = {
|
|
{ .procname = "net", },
|
|
{ .procname = "ipv4", },
|
|
{ },
|
|
};
|
|
|
|
static struct ctl_table ipv4_route_flush_table[] = {
|
|
{
|
|
.procname = "flush",
|
|
.maxlen = sizeof(int),
|
|
.mode = 0200,
|
|
.proc_handler = ipv4_sysctl_rtcache_flush,
|
|
},
|
|
{ },
|
|
};
|
|
|
|
static __net_initdata struct ctl_path ipv4_route_path[] = {
|
|
{ .procname = "net", },
|
|
{ .procname = "ipv4", },
|
|
{ .procname = "route", },
|
|
{ },
|
|
};
|
|
|
|
static __net_init int sysctl_route_net_init(struct net *net)
|
|
{
|
|
struct ctl_table *tbl;
|
|
|
|
tbl = ipv4_route_flush_table;
|
|
if (!net_eq(net, &init_net)) {
|
|
tbl = kmemdup(tbl, sizeof(ipv4_route_flush_table), GFP_KERNEL);
|
|
if (tbl == NULL)
|
|
goto err_dup;
|
|
}
|
|
tbl[0].extra1 = net;
|
|
|
|
net->ipv4.route_hdr =
|
|
register_net_sysctl_table(net, ipv4_route_path, tbl);
|
|
if (net->ipv4.route_hdr == NULL)
|
|
goto err_reg;
|
|
return 0;
|
|
|
|
err_reg:
|
|
if (tbl != ipv4_route_flush_table)
|
|
kfree(tbl);
|
|
err_dup:
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static __net_exit void sysctl_route_net_exit(struct net *net)
|
|
{
|
|
struct ctl_table *tbl;
|
|
|
|
tbl = net->ipv4.route_hdr->ctl_table_arg;
|
|
unregister_net_sysctl_table(net->ipv4.route_hdr);
|
|
BUG_ON(tbl == ipv4_route_flush_table);
|
|
kfree(tbl);
|
|
}
|
|
|
|
static __net_initdata struct pernet_operations sysctl_route_ops = {
|
|
.init = sysctl_route_net_init,
|
|
.exit = sysctl_route_net_exit,
|
|
};
|
|
#endif
|
|
|
|
static __net_init int rt_genid_init(struct net *net)
|
|
{
|
|
get_random_bytes(&net->ipv4.rt_genid,
|
|
sizeof(net->ipv4.rt_genid));
|
|
return 0;
|
|
}
|
|
|
|
static __net_initdata struct pernet_operations rt_genid_ops = {
|
|
.init = rt_genid_init,
|
|
};
|
|
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
|
|
#endif /* CONFIG_NET_CLS_ROUTE */
|
|
|
|
static __initdata unsigned long rhash_entries;
|
|
static int __init set_rhash_entries(char *str)
|
|
{
|
|
if (!str)
|
|
return 0;
|
|
rhash_entries = simple_strtoul(str, &str, 0);
|
|
return 1;
|
|
}
|
|
__setup("rhash_entries=", set_rhash_entries);
|
|
|
|
int __init ip_rt_init(void)
|
|
{
|
|
int rc = 0;
|
|
|
|
#ifdef CONFIG_NET_CLS_ROUTE
|
|
ip_rt_acct = __alloc_percpu(256 * sizeof(struct ip_rt_acct), __alignof__(struct ip_rt_acct));
|
|
if (!ip_rt_acct)
|
|
panic("IP: failed to allocate ip_rt_acct\n");
|
|
#endif
|
|
|
|
ipv4_dst_ops.kmem_cachep =
|
|
kmem_cache_create("ip_dst_cache", sizeof(struct rtable), 0,
|
|
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
|
|
|
|
ipv4_dst_blackhole_ops.kmem_cachep = ipv4_dst_ops.kmem_cachep;
|
|
|
|
if (dst_entries_init(&ipv4_dst_ops) < 0)
|
|
panic("IP: failed to allocate ipv4_dst_ops counter\n");
|
|
|
|
if (dst_entries_init(&ipv4_dst_blackhole_ops) < 0)
|
|
panic("IP: failed to allocate ipv4_dst_blackhole_ops counter\n");
|
|
|
|
rt_hash_table = (struct rt_hash_bucket *)
|
|
alloc_large_system_hash("IP route cache",
|
|
sizeof(struct rt_hash_bucket),
|
|
rhash_entries,
|
|
(totalram_pages >= 128 * 1024) ?
|
|
15 : 17,
|
|
0,
|
|
&rt_hash_log,
|
|
&rt_hash_mask,
|
|
rhash_entries ? 0 : 512 * 1024);
|
|
memset(rt_hash_table, 0, (rt_hash_mask + 1) * sizeof(struct rt_hash_bucket));
|
|
rt_hash_lock_init();
|
|
|
|
ipv4_dst_ops.gc_thresh = (rt_hash_mask + 1);
|
|
ip_rt_max_size = (rt_hash_mask + 1) * 16;
|
|
|
|
devinet_init();
|
|
ip_fib_init();
|
|
|
|
/* All the timers, started at system startup tend
|
|
to synchronize. Perturb it a bit.
|
|
*/
|
|
INIT_DELAYED_WORK_DEFERRABLE(&expires_work, rt_worker_func);
|
|
expires_ljiffies = jiffies;
|
|
schedule_delayed_work(&expires_work,
|
|
net_random() % ip_rt_gc_interval + ip_rt_gc_interval);
|
|
|
|
if (ip_rt_proc_init())
|
|
printk(KERN_ERR "Unable to create route proc files\n");
|
|
#ifdef CONFIG_XFRM
|
|
xfrm_init();
|
|
xfrm4_init(ip_rt_max_size);
|
|
#endif
|
|
rtnl_register(PF_INET, RTM_GETROUTE, inet_rtm_getroute, NULL);
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
register_pernet_subsys(&sysctl_route_ops);
|
|
#endif
|
|
register_pernet_subsys(&rt_genid_ops);
|
|
return rc;
|
|
}
|
|
|
|
#ifdef CONFIG_SYSCTL
|
|
/*
|
|
* We really need to sanitize the damn ipv4 init order, then all
|
|
* this nonsense will go away.
|
|
*/
|
|
void __init ip_static_sysctl_init(void)
|
|
{
|
|
register_sysctl_paths(ipv4_path, ipv4_skeleton);
|
|
}
|
|
#endif
|