[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/net/ipv4/route.c b/ap/os/linux/linux-3.4.x/net/ipv4/route.c
new file mode 100755
index 0000000..29e211d
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/net/ipv4/route.c
@@ -0,0 +1,3572 @@
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * ROUTE - implementation of the IP router.
+ *
+ * Authors: Ross Biro
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Alan Cox, <gw4pts@gw4pts.ampr.org>
+ * Linus Torvalds, <Linus.Torvalds@helsinki.fi>
+ * Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
+ *
+ * Fixes:
+ * Alan Cox : Verify area fixes.
+ * Alan Cox : cli() protects routing changes
+ * Rui Oliveira : ICMP routing table updates
+ * (rco@di.uminho.pt) Routing table insertion and update
+ * Linus Torvalds : Rewrote bits to be sensible
+ * Alan Cox : Added BSD route gw semantics
+ * Alan Cox : Super /proc >4K
+ * Alan Cox : MTU in route table
+ * Alan Cox : MSS actually. Also added the window
+ * clamper.
+ * Sam Lantinga : Fixed route matching in rt_del()
+ * Alan Cox : Routing cache support.
+ * Alan Cox : Removed compatibility cruft.
+ * Alan Cox : RTF_REJECT support.
+ * Alan Cox : TCP irtt support.
+ * Jonathan Naylor : Added Metric support.
+ * Miquel van Smoorenburg : BSD API fixes.
+ * Miquel van Smoorenburg : Metrics.
+ * Alan Cox : Use __u32 properly
+ * Alan Cox : Aligned routing errors more closely with BSD
+ * our system is still very different.
+ * Alan Cox : Faster /proc handling
+ * Alexey Kuznetsov : Massive rework to support tree based routing,
+ * routing caches and better behaviour.
+ *
+ * Olaf Erb : irtt wasn't being copied right.
+ * Bjorn Ekwall : Kerneld route support.
+ * Alan Cox : Multicast fixed (I hope)
+ * Pavel Krauz : Limited broadcast fixed
+ * Mike McLagan : Routing by source
+ * Alexey Kuznetsov : End of old history. Split to fib.c and
+ * route.c and rewritten from scratch.
+ * Andi Kleen : Load-limit warning messages.
+ * Vitaly E. Lavrov : Transparent proxy revived after year coma.
+ * Vitaly E. Lavrov : Race condition in ip_route_input_slow.
+ * Tobias Ringstrom : Uninitialized res.type in ip_route_output_slow.
+ * Vladimir V. Ivanov : IP rule info (flowid) is really useful.
+ * Marc Boucher : routing by fwmark
+ * Robert Olsson : Added rt_cache statistics
+ * Arnaldo C. Melo : Convert proc stuff to seq_file
+ * Eric Dumazet : hashed spinlocks and rt_check_expire() fixes.
+ * Ilia Sotnikov : Ignore TOS on PMTUD and Redirect
+ * Ilia Sotnikov : Removed TOS from hash calculations
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#define pr_fmt(fmt) "IPv4: " fmt
+
+#include <linux/module.h>
+#include <asm/uaccess.h>
+#include <linux/bitops.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/string.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/netdevice.h>
+#include <linux/proc_fs.h>
+#include <linux/init.h>
+#include <linux/workqueue.h>
+#include <linux/skbuff.h>
+#include <linux/inetdevice.h>
+#include <linux/igmp.h>
+#include <linux/pkt_sched.h>
+#include <linux/mroute.h>
+#include <linux/netfilter_ipv4.h>
+#include <linux/random.h>
+#include <linux/jhash.h>
+#include <linux/rcupdate.h>
+#include <linux/times.h>
+#include <linux/slab.h>
+#include <linux/prefetch.h>
+#include <net/dst.h>
+#include <net/net_namespace.h>
+#include <net/protocol.h>
+#include <net/ip.h>
+#include <net/route.h>
+#include <net/inetpeer.h>
+#include <net/sock.h>
+#include <net/ip_fib.h>
+#include <net/arp.h>
+#include <net/tcp.h>
+#include <net/icmp.h>
+#include <net/xfrm.h>
+#include <net/netevent.h>
+#include <net/rtnetlink.h>
+#ifdef CONFIG_SYSCTL
+#include <linux/sysctl.h>
+#endif
+#include <net/secure_seq.h>
+#include <net/SI/print_sun.h>
+
+
+#define RT_FL_TOS(oldflp4) \
+ ((oldflp4)->flowi4_tos & (IPTOS_RT_MASK | RTO_ONLINK))
+
+#define IP_MAX_MTU 0xFFF0
+
+#define RT_GC_TIMEOUT (300*HZ)
+
+static int ip_rt_max_size;
+static int ip_rt_gc_timeout __read_mostly = RT_GC_TIMEOUT;
+static int ip_rt_gc_interval __read_mostly = 60 * HZ;
+static int ip_rt_gc_min_interval __read_mostly = HZ / 2;
+static int ip_rt_redirect_number __read_mostly = 9;
+static int ip_rt_redirect_load __read_mostly = HZ / 50;
+static int ip_rt_redirect_silence __read_mostly = ((HZ / 50) << (9 + 1));
+static int ip_rt_error_cost __read_mostly = HZ;
+static int ip_rt_error_burst __read_mostly = 5 * HZ;
+static int ip_rt_gc_elasticity __read_mostly = 8;
+static int ip_rt_mtu_expires __read_mostly = 10 * 60 * HZ;
+static int ip_rt_min_pmtu __read_mostly = 512 + 20 + 20;
+static int ip_rt_min_advmss __read_mostly = 256;
+static int rt_chain_length_max __read_mostly = 20;
+
+static struct delayed_work expires_work;
+static unsigned long expires_ljiffies;
+
+/*
+ * Interface to generic destination cache.
+ */
+
+static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie);
+static unsigned int ipv4_default_advmss(const struct dst_entry *dst);
+static unsigned int ipv4_mtu(const struct dst_entry *dst);
+static void ipv4_dst_destroy(struct dst_entry *dst);
+static struct dst_entry *ipv4_negative_advice(struct dst_entry *dst);
+static void ipv4_link_failure(struct sk_buff *skb);
+static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu);
+static int rt_garbage_collect(struct dst_ops *ops);
+
+static void __rt_garbage_collect(struct work_struct *w);
+static DECLARE_WORK(rt_gc_worker, __rt_garbage_collect);
+
+static void ipv4_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
+ int how)
+{
+}
+
+static u32 *ipv4_cow_metrics(struct dst_entry *dst, unsigned long old)
+{
+ struct rtable *rt = (struct rtable *) dst;
+ struct inet_peer *peer;
+ u32 *p = NULL;
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 1);
+
+ peer = rt->peer;
+ if (peer) {
+ u32 *old_p = __DST_METRICS_PTR(old);
+ unsigned long prev, new;
+
+ p = peer->metrics;
+ if (inet_metrics_new(peer))
+ memcpy(p, old_p, sizeof(u32) * RTAX_MAX);
+
+ new = (unsigned long) p;
+ prev = cmpxchg(&dst->_metrics, old, new);
+
+ if (prev != old) {
+ p = __DST_METRICS_PTR(prev);
+ if (prev & DST_METRICS_READ_ONLY)
+ p = NULL;
+ } else {
+ if (rt->fi) {
+ fib_info_put(rt->fi);
+ rt->fi = NULL;
+ }
+ }
+ }
+ return p;
+}
+
+static struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr);
+
+static struct dst_ops ipv4_dst_ops = {
+ .family = AF_INET,
+ .protocol = cpu_to_be16(ETH_P_IP),
+ .gc = rt_garbage_collect,
+ .check = ipv4_dst_check,
+ .default_advmss = ipv4_default_advmss,
+ .mtu = ipv4_mtu,
+ .cow_metrics = ipv4_cow_metrics,
+ .destroy = ipv4_dst_destroy,
+ .ifdown = ipv4_dst_ifdown,
+ .negative_advice = ipv4_negative_advice,
+ .link_failure = ipv4_link_failure,
+ .update_pmtu = ip_rt_update_pmtu,
+ .local_out = __ip_local_out,
+ .neigh_lookup = ipv4_neigh_lookup,
+};
+
+#define ECN_OR_COST(class) TC_PRIO_##class
+
+const __u8 ip_tos2prio[16] = {
+ TC_PRIO_BESTEFFORT,
+ ECN_OR_COST(BESTEFFORT),
+ TC_PRIO_BESTEFFORT,
+ ECN_OR_COST(BESTEFFORT),
+ TC_PRIO_BULK,
+ ECN_OR_COST(BULK),
+ TC_PRIO_BULK,
+ ECN_OR_COST(BULK),
+ TC_PRIO_INTERACTIVE,
+ ECN_OR_COST(INTERACTIVE),
+ TC_PRIO_INTERACTIVE,
+ ECN_OR_COST(INTERACTIVE),
+ TC_PRIO_INTERACTIVE_BULK,
+ ECN_OR_COST(INTERACTIVE_BULK),
+ TC_PRIO_INTERACTIVE_BULK,
+ ECN_OR_COST(INTERACTIVE_BULK)
+};
+
+
+/*
+ * Route cache.
+ */
+
+/* The locking scheme is rather straight forward:
+ *
+ * 1) Read-Copy Update protects the buckets of the central route hash.
+ * 2) Only writers remove entries, and they hold the lock
+ * as they look at rtable reference counts.
+ * 3) Only readers acquire references to rtable entries,
+ * they do so with atomic increments and with the
+ * lock held.
+ */
+
+struct rt_hash_bucket {
+ struct rtable __rcu *chain;
+};
+
+#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) || \
+ defined(CONFIG_PROVE_LOCKING) || defined(CONFIG_PREEMPT_RT_FULL)
+/*
+ * Instead of using one spinlock for each rt_hash_bucket, we use a table of spinlocks
+ * The size of this table is a power of two and depends on the number of CPUS.
+ * (on lockdep we have a quite big spinlock_t, so keep the size down there)
+ */
+#ifdef CONFIG_LOCKDEP
+# define RT_HASH_LOCK_SZ 256
+#else
+# if NR_CPUS >= 32
+# define RT_HASH_LOCK_SZ 4096
+# elif NR_CPUS >= 16
+# define RT_HASH_LOCK_SZ 2048
+# elif NR_CPUS >= 8
+# define RT_HASH_LOCK_SZ 1024
+# elif NR_CPUS >= 4
+# define RT_HASH_LOCK_SZ 512
+# else
+# define RT_HASH_LOCK_SZ 256
+# endif
+#endif
+
+static spinlock_t *rt_hash_locks;
+# define rt_hash_lock_addr(slot) &rt_hash_locks[(slot) & (RT_HASH_LOCK_SZ - 1)]
+
+static __init void rt_hash_lock_init(void)
+{
+ int i;
+
+ rt_hash_locks = kmalloc(sizeof(spinlock_t) * RT_HASH_LOCK_SZ,
+ GFP_KERNEL);
+ if (!rt_hash_locks)
+ panic("IP: failed to allocate rt_hash_locks\n");
+
+ for (i = 0; i < RT_HASH_LOCK_SZ; i++)
+ spin_lock_init(&rt_hash_locks[i]);
+}
+#else
+# define rt_hash_lock_addr(slot) NULL
+
+static inline void rt_hash_lock_init(void)
+{
+}
+#endif
+
+static struct rt_hash_bucket *rt_hash_table __read_mostly;
+static unsigned rt_hash_mask __read_mostly;
+static unsigned int rt_hash_log __read_mostly;
+
+static DEFINE_PER_CPU(struct rt_cache_stat, rt_cache_stat);
+#define RT_CACHE_STAT_INC(field) __this_cpu_inc(rt_cache_stat.field)
+
+static inline unsigned int rt_hash(__be32 daddr, __be32 saddr, int idx,
+ int genid)
+{
+ return jhash_3words((__force u32)daddr, (__force u32)saddr,
+ idx, genid)
+ & rt_hash_mask;
+}
+
+static inline int rt_genid(struct net *net)
+{
+ return atomic_read(&net->ipv4.rt_genid);
+}
+
+#ifdef CONFIG_PROC_FS
+struct rt_cache_iter_state {
+ struct seq_net_private p;
+ int bucket;
+ int genid;
+};
+
+static struct rtable *rt_cache_get_first(struct seq_file *seq)
+{
+ struct rt_cache_iter_state *st = seq->private;
+ struct rtable *r = NULL;
+
+ for (st->bucket = rt_hash_mask; st->bucket >= 0; --st->bucket) {
+ if (!rcu_access_pointer(rt_hash_table[st->bucket].chain))
+ continue;
+ rcu_read_lock_bh();
+ r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
+ while (r) {
+ if (dev_net(r->dst.dev) == seq_file_net(seq) &&
+ r->rt_genid == st->genid)
+ return r;
+ r = rcu_dereference_bh(r->dst.rt_next);
+ }
+ rcu_read_unlock_bh();
+ }
+ net_run_track(PRT_ROUTE," route");
+ return r;
+}
+
+static struct rtable *__rt_cache_get_next(struct seq_file *seq,
+ struct rtable *r)
+{
+ struct rt_cache_iter_state *st = seq->private;
+
+ r = rcu_dereference_bh(r->dst.rt_next);
+ while (!r) {
+ rcu_read_unlock_bh();
+ do {
+ if (--st->bucket < 0)
+ return NULL;
+ } while (!rcu_access_pointer(rt_hash_table[st->bucket].chain));
+ rcu_read_lock_bh();
+ r = rcu_dereference_bh(rt_hash_table[st->bucket].chain);
+ }
+ return r;
+}
+
+static struct rtable *rt_cache_get_next(struct seq_file *seq,
+ struct rtable *r)
+{
+ struct rt_cache_iter_state *st = seq->private;
+ while ((r = __rt_cache_get_next(seq, r)) != NULL) {
+ if (dev_net(r->dst.dev) != seq_file_net(seq))
+ continue;
+ if (r->rt_genid == st->genid)
+ break;
+ }
+ return r;
+}
+
+static struct rtable *rt_cache_get_idx(struct seq_file *seq, loff_t pos)
+{
+ struct rtable *r = rt_cache_get_first(seq);
+
+ if (r)
+ while (pos && (r = rt_cache_get_next(seq, r)))
+ --pos;
+ return pos ? NULL : r;
+}
+
+static void *rt_cache_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ struct rt_cache_iter_state *st = seq->private;
+ if (*pos)
+ return rt_cache_get_idx(seq, *pos - 1);
+ st->genid = rt_genid(seq_file_net(seq));
+ return SEQ_START_TOKEN;
+}
+
+static void *rt_cache_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ struct rtable *r;
+
+ if (v == SEQ_START_TOKEN)
+ r = rt_cache_get_first(seq);
+ else
+ r = rt_cache_get_next(seq, v);
+ ++*pos;
+ return r;
+}
+
+static void rt_cache_seq_stop(struct seq_file *seq, void *v)
+{
+ if (v && v != SEQ_START_TOKEN)
+ rcu_read_unlock_bh();
+}
+
+static int rt_cache_seq_show(struct seq_file *seq, void *v)
+{
+ if (v == SEQ_START_TOKEN)
+ seq_printf(seq, "%-127s\n",
+ "Iface\tDestination\tGateway \tFlags\t\tRefCnt\tUse\t"
+ "Metric\tSource\t\tMTU\tWindow\tIRTT\tTOS\tHHRef\t"
+ "HHUptod\tSpecDst");
+ else {
+ struct rtable *r = v;
+ struct neighbour *n;
+ int len, HHUptod;
+
+ rcu_read_lock();
+ n = dst_get_neighbour_noref(&r->dst);
+ HHUptod = (n && (n->nud_state & NUD_CONNECTED)) ? 1 : 0;
+ rcu_read_unlock();
+
+ seq_printf(seq, "%s\t%08X\t%08X\t%8X\t%d\t%u\t%d\t"
+ "%08X\t%d\t%u\t%u\t%02X\t%d\t%1d\t%08X%n",
+ r->dst.dev ? r->dst.dev->name : "*",
+ (__force u32)r->rt_dst,
+ (__force u32)r->rt_gateway,
+ r->rt_flags, atomic_read(&r->dst.__refcnt),
+ r->dst.__use, 0, (__force u32)r->rt_src,
+ dst_metric_advmss(&r->dst) + 40,
+ dst_metric(&r->dst, RTAX_WINDOW),
+ (int)((dst_metric(&r->dst, RTAX_RTT) >> 3) +
+ dst_metric(&r->dst, RTAX_RTTVAR)),
+ r->rt_key_tos,
+ -1,
+ HHUptod,
+ r->rt_spec_dst, &len);
+
+ seq_printf(seq, "%*s\n", 127 - len, "");
+ }
+ return 0;
+}
+
+static const struct seq_operations rt_cache_seq_ops = {
+ .start = rt_cache_seq_start,
+ .next = rt_cache_seq_next,
+ .stop = rt_cache_seq_stop,
+ .show = rt_cache_seq_show,
+};
+
+static int rt_cache_seq_open(struct inode *inode, struct file *file)
+{
+ return seq_open_net(inode, file, &rt_cache_seq_ops,
+ sizeof(struct rt_cache_iter_state));
+}
+
+static const struct file_operations rt_cache_seq_fops = {
+ .owner = THIS_MODULE,
+ .open = rt_cache_seq_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release_net,
+};
+
+
+static void *rt_cpu_seq_start(struct seq_file *seq, loff_t *pos)
+{
+ int cpu;
+
+ if (*pos == 0)
+ return SEQ_START_TOKEN;
+
+ for (cpu = *pos-1; cpu < nr_cpu_ids; ++cpu) {
+ if (!cpu_possible(cpu))
+ continue;
+ *pos = cpu+1;
+ return &per_cpu(rt_cache_stat, cpu);
+ }
+ return NULL;
+}
+
+static void *rt_cpu_seq_next(struct seq_file *seq, void *v, loff_t *pos)
+{
+ int cpu;
+
+ for (cpu = *pos; cpu < nr_cpu_ids; ++cpu) {
+ if (!cpu_possible(cpu))
+ continue;
+ *pos = cpu+1;
+ return &per_cpu(rt_cache_stat, cpu);
+ }
+ return NULL;
+
+}
+
+static void rt_cpu_seq_stop(struct seq_file *seq, void *v)
+{
+
+}
+
+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_IP_ROUTE_CLASSID
+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_IP_ROUTE_CLASSID
+ pde = proc_create("rt_acct", 0, net->proc_net, &rt_acct_proc_fops);
+ if (!pde)
+ goto err3;
+#endif
+ return 0;
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+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_IP_ROUTE_CLASSID
+ 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)
+{
+ if (IS_ENABLED(CONFIG_PROC_STRIPPED))
+ return 0;
+
+ 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)
+{
+ net_run_track(PRT_ROUTE," free");
+ netruninfo_add(NULL, RT_HASH_DEL);
+ 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->peer && rth->peer->pmtu_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;
+
+ age = jiffies - rth->dst.lastuse;
+ 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 rtable *rt1,
+ const struct rtable *rt2)
+{
+ return ((((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) |
+ ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) |
+ (rt1->rt_route_iif ^ rt2->rt_route_iif)) == 0);
+}
+
+static inline int compare_keys(struct rtable *rt1, struct rtable *rt2)
+{
+ return (((__force u32)rt1->rt_key_dst ^ (__force u32)rt2->rt_key_dst) |
+ ((__force u32)rt1->rt_key_src ^ (__force u32)rt2->rt_key_src) |
+ (rt1->rt_mark ^ rt2->rt_mark) |
+ (rt1->rt_key_tos ^ rt2->rt_key_tos) |
+ (rt1->rt_route_iif ^ rt2->rt_route_iif) |
+ (rt1->rt_oif ^ rt2->rt_oif)) == 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_access_pointer(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);
+ }
+ net_run_track(PRT_ROUTE,"flush route:%d",process_context);
+ }
+}
+
+/*
+ * 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, rth))
+ 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);
+}
+
+/*
+ * Perturbation 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;
+ netruninfo_add(NULL, RT_CACHE_INVALID);
+ get_random_bytes(&shuffle, sizeof(shuffle));
+ atomic_add(shuffle + 1U, &net->ipv4.rt_genid);
+ inetpeer_invalidate_tree(AF_INET);
+}
+
+/*
+ * 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())
+ pr_warn("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 void __do_rt_garbage_collect(int elasticity, int min_interval)
+{
+ static unsigned long expire = RT_GC_TIMEOUT;
+ static unsigned long last_gc;
+ static int rover;
+ static int equilibrium;
+ static DEFINE_SPINLOCK(rt_gc_lock);
+ 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.
+ */
+
+ spin_lock_bh(&rt_gc_lock);
+
+ RT_CACHE_STAT_INC(gc_total);
+
+ if (now - last_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 - (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 >= 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 (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())
+ pr_warn("dst cache overflow\n");
+ RT_CACHE_STAT_INC(gc_dst_overflow);
+ goto out;
+
+work_done:
+ expire += 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;
+out:
+ spin_unlock_bh(&rt_gc_lock);
+}
+
+static void __rt_garbage_collect(struct work_struct *w)
+{
+ __do_rt_garbage_collect(ip_rt_gc_elasticity, ip_rt_gc_min_interval);
+}
+
+static int rt_garbage_collect(struct dst_ops *ops)
+{
+ if (!work_pending(&rt_gc_worker))
+ schedule_work(&rt_gc_worker);
+
+ if (dst_entries_get_fast(&ipv4_dst_ops) >= ip_rt_max_size ||
+ dst_entries_get_slow(&ipv4_dst_ops) >= ip_rt_max_size) {
+ RT_CACHE_STAT_INC(gc_dst_overflow);
+ return 1;
+ }
+ 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 struct neighbour *ipv4_neigh_lookup(const struct dst_entry *dst, const void *daddr)
+{
+ static const __be32 inaddr_any = 0;
+ struct net_device *dev = dst->dev;
+ const __be32 *pkey = daddr;
+ const struct rtable *rt;
+ struct neighbour *n;
+
+ rt = (const struct rtable *) dst;
+
+ if (dev->flags & (IFF_LOOPBACK | IFF_POINTOPOINT))
+ pkey = &inaddr_any;
+ else if (rt->rt_gateway)
+ pkey = (const __be32 *) &rt->rt_gateway;
+
+ n = __ipv4_neigh_lookup(dev, *(__force u32 *)pkey);
+ if (n)
+ return n;
+ return neigh_create(&arp_tbl, pkey, dev);
+}
+
+static int rt_bind_neighbour(struct rtable *rt)
+{
+ struct neighbour *n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
+ if (IS_ERR(n))
+ return PTR_ERR(n);
+ dst_set_neighbour(&rt->dst, n);
+
+ return 0;
+}
+
+static struct rtable *rt_intern_hash(unsigned hash, struct rtable *rt,
+ 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 = 1;
+
+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 = rt_bind_neighbour(rt);
+ if (err) {
+ if (net_ratelimit())
+ pr_warn("Neighbour table failure & not caching routes\n");
+ ip_rt_put(rt);
+ return ERR_PTR(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, rt) && 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 (skb)
+ skb_dst_set(skb, &rth->dst);
+ net_run_track(PRT_ROUTE," route");
+ return rth;
+ }
+
+ 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)) {
+ pr_warn("%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->rt_key_dst, rt->rt_key_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 = rt_bind_neighbour(rt);
+ if (err) {
+ spin_unlock_bh(rt_hash_lock_addr(hash));
+
+ if (err != -ENOBUFS) {
+ rt_drop(rt);
+ return ERR_PTR(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 (!in_softirq() && attempts-- > 0) {
+ static DEFINE_SPINLOCK(lock);
+
+ if (spin_trylock(&lock)) {
+ __do_rt_garbage_collect(1, 0);
+ spin_unlock(&lock);
+ } else {
+ spin_unlock_wait(&lock);
+ }
+ goto restart;
+ }
+
+ if (net_ratelimit())
+ pr_warn("Neighbour table overflow\n");
+ rt_drop(rt);
+ return ERR_PTR(-ENOBUFS);
+ }
+ }
+
+ rt->dst.rt_next = rt_hash_table[hash].chain;
+
+ /*
+ * Since lookup is lockfree, we must make sure
+ * previous writes to rt are committed to memory
+ * before making rt visible to other CPUS.
+ */
+ rcu_assign_pointer(rt_hash_table[hash].chain, rt);
+ netruninfo_add(NULL, RT_HASH_ADD);
+
+ spin_unlock_bh(rt_hash_lock_addr(hash));
+
+skip_hashing:
+ if (skb)
+ skb_dst_set(skb, &rt->dst);
+ net_run_track(PRT_ROUTE," rt_intern_hash");
+ return rt;
+}
+
+static atomic_t __rt_peer_genid = ATOMIC_INIT(0);
+
+static u32 rt_peer_genid(void)
+{
+ return atomic_read(&__rt_peer_genid);
+}
+
+void rt_bind_peer(struct rtable *rt, __be32 daddr, int create)
+{
+ struct inet_peer *peer;
+
+ peer = inet_getpeer_v4(daddr, create);
+
+ if (peer && cmpxchg(&rt->peer, NULL, peer) != NULL)
+ inet_putpeer(peer);
+ else
+ rt->rt_peer_genid = rt_peer_genid();
+}
+
+#define IP_IDENTS_SZ 2048u
+struct ip_ident_bucket {
+ atomic_t id;
+ u32 stamp32;
+};
+
+static struct ip_ident_bucket *ip_idents __read_mostly;
+
+/* In order to protect privacy, we add a perturbation to identifiers
+ * if one generator is seldom used. This makes hard for an attacker
+ * to infer how many packets were sent between two points in time.
+ */
+u32 ip_idents_reserve(u32 hash, int segs)
+{
+ struct ip_ident_bucket *bucket = ip_idents + hash % IP_IDENTS_SZ;
+ u32 old = ACCESS_ONCE(bucket->stamp32);
+ u32 now = (u32)jiffies;
+ u32 delta = 0;
+
+ if (old != now && cmpxchg(&bucket->stamp32, old, now) == old) {
+ u64 x = random32();
+
+ x *= (now - old);
+ delta = (u32)(x >> 32);
+ }
+
+ return atomic_add_return(segs + delta, &bucket->id) - segs;
+}
+EXPORT_SYMBOL(ip_idents_reserve);
+
+void __ip_select_ident(struct iphdr *iph, int segs)
+{
+ static u32 ip_idents_hashrnd __read_mostly;
+ static bool hashrnd_initialized = false;
+ u32 hash, id;
+
+ if (unlikely(!hashrnd_initialized)) {
+ hashrnd_initialized = true;
+ get_random_bytes(&ip_idents_hashrnd, sizeof(ip_idents_hashrnd));
+ }
+
+ hash = jhash_3words((__force u32)iph->daddr,
+ (__force u32)iph->saddr,
+ iph->protocol,
+ ip_idents_hashrnd);
+ id = ip_idents_reserve(hash, segs);
+ iph->id = htons(id);
+}
+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));
+}
+
+static void check_peer_redir(struct dst_entry *dst, struct inet_peer *peer)
+{
+ struct rtable *rt = (struct rtable *) dst;
+ __be32 orig_gw = rt->rt_gateway;
+ struct neighbour *n, *old_n;
+
+ dst_confirm(&rt->dst);
+
+ rt->rt_gateway = peer->redirect_learned.a4;
+
+ n = ipv4_neigh_lookup(&rt->dst, &rt->rt_gateway);
+ if (IS_ERR(n)) {
+ rt->rt_gateway = orig_gw;
+ return;
+ }
+ net_run_track(PRT_ROUTE," redirect");
+ old_n = xchg(&rt->dst._neighbour, n);
+ if (old_n)
+ neigh_release(old_n);
+ if (!(n->nud_state & NUD_VALID)) {
+ neigh_event_send(n, NULL);
+ } else {
+ rt->rt_flags |= RTCF_REDIRECTED;
+ call_netevent_notifiers(NETEVENT_NEIGH_UPDATE, n);
+ }
+}
+
+/* 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 s, i;
+ struct in_device *in_dev = __in_dev_get_rcu(dev);
+ __be32 skeys[2] = { saddr, 0 };
+ int ikeys[2] = { dev->ifindex, 0 };
+ struct inet_peer *peer;
+ 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 (!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 (s = 0; s < 2; s++) {
+ for (i = 0; i < 2; i++) {
+ unsigned int hash;
+ struct rtable __rcu **rthp;
+ struct rtable *rt;
+
+ hash = rt_hash(daddr, skeys[s], ikeys[i], rt_genid(net));
+
+ rthp = &rt_hash_table[hash].chain;
+
+ while ((rt = rcu_dereference(*rthp)) != NULL) {
+ rthp = &rt->dst.rt_next;
+
+ if (rt->rt_key_dst != daddr ||
+ rt->rt_key_src != skeys[s] ||
+ rt->rt_oif != ikeys[i] ||
+ rt_is_input_route(rt) ||
+ rt_is_expired(rt) ||
+ !net_eq(dev_net(rt->dst.dev), net) ||
+ rt->dst.error ||
+ rt->dst.dev != dev ||
+ rt->rt_gateway != old_gw)
+ continue;
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 1);
+
+ peer = rt->peer;
+ if (peer) {
+ if (peer->redirect_learned.a4 != new_gw) {
+ peer->redirect_learned.a4 = new_gw;
+ atomic_inc(&__rt_peer_genid);
+ }
+ check_peer_redir(&rt->dst, peer);
+ }
+ }
+ }
+ }
+ return;
+
+reject_redirect:
+#ifdef CONFIG_IP_ROUTE_VERBOSE
+ if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
+ pr_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 bool peer_pmtu_expired(struct inet_peer *peer)
+{
+ unsigned long orig = ACCESS_ONCE(peer->pmtu_expires);
+
+ return orig &&
+ time_after_eq(jiffies, orig) &&
+ cmpxchg(&peer->pmtu_expires, orig, 0) == orig;
+}
+
+static bool peer_pmtu_cleaned(struct inet_peer *peer)
+{
+ unsigned long orig = ACCESS_ONCE(peer->pmtu_expires);
+
+ return orig &&
+ cmpxchg(&peer->pmtu_expires, orig, 0) == orig;
+}
+
+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) {
+ unsigned hash = rt_hash(rt->rt_key_dst, rt->rt_key_src,
+ rt->rt_oif,
+ rt_genid(dev_net(dst->dev)));
+ rt_del(hash, rt);
+ ret = NULL;
+ } else if (rt->peer && peer_pmtu_expired(rt->peer)) {
+ dst_metric_set(dst, RTAX_MTU, rt->peer->pmtu_orig);
+ }
+ }
+ 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;
+ struct inet_peer *peer;
+ 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();
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 1);
+ peer = rt->peer;
+ if (!peer) {
+ icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
+ return;
+ }
+
+ /* No redirected packets during ip_rt_redirect_silence;
+ * reset the algorithm.
+ */
+ if (time_after(jiffies, peer->rate_last + ip_rt_redirect_silence))
+ peer->rate_tokens = 0;
+
+ /* Too many ignored redirects; do not send anything
+ * set dst.rate_last to the last seen redirected packet.
+ */
+ if (peer->rate_tokens >= ip_rt_redirect_number) {
+ peer->rate_last = jiffies;
+ return;
+ }
+
+ /* Check for load limit; set rate_last to the latest sent
+ * redirect.
+ */
+ if (peer->rate_tokens == 0 ||
+ time_after(jiffies,
+ (peer->rate_last +
+ (ip_rt_redirect_load << peer->rate_tokens)))) {
+ icmp_send(skb, ICMP_REDIRECT, ICMP_REDIR_HOST, rt->rt_gateway);
+ peer->rate_last = jiffies;
+ ++peer->rate_tokens;
+#ifdef CONFIG_IP_ROUTE_VERBOSE
+ if (log_martians &&
+ peer->rate_tokens == ip_rt_redirect_number &&
+ net_ratelimit())
+ pr_warn("host %pI4/if%d ignores redirects for %pI4 to %pI4\n",
+ &ip_hdr(skb)->saddr, rt->rt_iif,
+ &rt->rt_dst, &rt->rt_gateway);
+#endif
+ }
+}
+
+static int ip_error(struct sk_buff *skb)
+{
+ struct rtable *rt = skb_rtable(skb);
+ struct inet_peer *peer;
+ unsigned long now;
+ bool send;
+ 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;
+ }
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 1);
+ peer = rt->peer;
+
+ send = true;
+ if (peer) {
+ now = jiffies;
+ peer->rate_tokens += now - peer->rate_last;
+ if (peer->rate_tokens > ip_rt_error_burst)
+ peer->rate_tokens = ip_rt_error_burst;
+ peer->rate_last = now;
+ if (peer->rate_tokens >= ip_rt_error_cost)
+ peer->rate_tokens -= ip_rt_error_cost;
+ else
+ send = false;
+ }
+ if (send)
+ 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, const struct iphdr *iph,
+ unsigned short new_mtu,
+ struct net_device *dev)
+{
+ unsigned short old_mtu = ntohs(iph->tot_len);
+ unsigned short est_mtu = 0;
+ struct inet_peer *peer;
+
+ peer = inet_getpeer_v4(iph->daddr, 1);
+ if (peer) {
+ unsigned short mtu = new_mtu;
+
+ if (new_mtu < 68 || new_mtu >= old_mtu) {
+ /* BSD 4.2 derived systems incorrectly adjust
+ * tot_len by the IP header length, and report
+ * a zero MTU in the ICMP message.
+ */
+ if (mtu == 0 &&
+ old_mtu >= 68 + (iph->ihl << 2))
+ old_mtu -= iph->ihl << 2;
+ mtu = guess_mtu(old_mtu);
+ }
+
+ if (mtu < ip_rt_min_pmtu)
+ mtu = ip_rt_min_pmtu;
+ if (!peer->pmtu_expires || mtu < peer->pmtu_learned) {
+ unsigned long pmtu_expires;
+
+ pmtu_expires = jiffies + ip_rt_mtu_expires;
+ if (!pmtu_expires)
+ pmtu_expires = 1UL;
+
+ est_mtu = mtu;
+ peer->pmtu_learned = mtu;
+ peer->pmtu_expires = pmtu_expires;
+ atomic_inc(&__rt_peer_genid);
+ }
+
+ inet_putpeer(peer);
+ }
+ return est_mtu ? : new_mtu;
+}
+
+static void check_peer_pmtu(struct dst_entry *dst, struct inet_peer *peer)
+{
+ unsigned long expires = ACCESS_ONCE(peer->pmtu_expires);
+
+ if (!expires)
+ return;
+ if (time_before(jiffies, expires)) {
+ u32 orig_dst_mtu = dst_mtu(dst);
+ if (peer->pmtu_learned < orig_dst_mtu) {
+ if (!peer->pmtu_orig)
+ peer->pmtu_orig = dst_metric_raw(dst, RTAX_MTU);
+ dst_metric_set(dst, RTAX_MTU, peer->pmtu_learned);
+ }
+ } else if (cmpxchg(&peer->pmtu_expires, expires, 0) == expires)
+ dst_metric_set(dst, RTAX_MTU, peer->pmtu_orig);
+}
+
+static void ip_rt_update_pmtu(struct dst_entry *dst, u32 mtu)
+{
+ struct rtable *rt = (struct rtable *) dst;
+ struct inet_peer *peer;
+
+ dst_confirm(dst);
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 1);
+ peer = rt->peer;
+ if (peer) {
+ unsigned long pmtu_expires = ACCESS_ONCE(peer->pmtu_expires);
+
+ if (mtu < ip_rt_min_pmtu)
+ mtu = ip_rt_min_pmtu;
+ if (!pmtu_expires || mtu < peer->pmtu_learned) {
+
+ pmtu_expires = jiffies + ip_rt_mtu_expires;
+ if (!pmtu_expires)
+ pmtu_expires = 1UL;
+
+ peer->pmtu_learned = mtu;
+ peer->pmtu_expires = pmtu_expires;
+
+ atomic_inc(&__rt_peer_genid);
+ rt->rt_peer_genid = rt_peer_genid();
+ }
+ check_peer_pmtu(dst, peer);
+ }
+}
+
+
+static void ipv4_validate_peer(struct rtable *rt)
+{
+ if (rt->rt_peer_genid != rt_peer_genid()) {
+ struct inet_peer *peer;
+
+ if (!rt->peer)
+ rt_bind_peer(rt, rt->rt_dst, 0);
+
+ peer = rt->peer;
+ if (peer) {
+ check_peer_pmtu(&rt->dst, peer);
+
+ if (peer->redirect_learned.a4 &&
+ peer->redirect_learned.a4 != rt->rt_gateway)
+ check_peer_redir(&rt->dst, peer);
+ }
+
+ rt->rt_peer_genid = rt_peer_genid();
+ }
+}
+
+static struct dst_entry *ipv4_dst_check(struct dst_entry *dst, u32 cookie)
+{
+ struct rtable *rt = (struct rtable *) dst;
+
+ if (rt_is_expired(rt))
+ return NULL;
+ ipv4_validate_peer(rt);
+ return dst;
+}
+
+static void ipv4_dst_destroy(struct dst_entry *dst)
+{
+ struct rtable *rt = (struct rtable *) dst;
+ struct inet_peer *peer = rt->peer;
+
+ if (rt->fi) {
+ fib_info_put(rt->fi);
+ rt->fi = NULL;
+ }
+ 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 && rt->peer && peer_pmtu_cleaned(rt->peer))
+ dst_metric_set(&rt->dst, RTAX_MTU, rt->peer->pmtu_orig);
+}
+
+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);
+ WARN_ON(1);
+ 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 sk_buff *skb, struct rtable *rt)
+{
+ __be32 src;
+
+ if (rt_is_output_route(rt))
+ src = ip_hdr(skb)->saddr;
+ else {
+ struct fib_result res;
+ struct flowi4 fl4;
+ struct iphdr *iph;
+
+ iph = ip_hdr(skb);
+
+ memset(&fl4, 0, sizeof(fl4));
+ fl4.daddr = iph->daddr;
+ fl4.saddr = iph->saddr;
+ fl4.flowi4_tos = RT_TOS(iph->tos);
+ fl4.flowi4_oif = rt->dst.dev->ifindex;
+ fl4.flowi4_iif = skb->dev->ifindex;
+ fl4.flowi4_mark = skb->mark;
+
+ rcu_read_lock();
+ if (fib_lookup(dev_net(rt->dst.dev), &fl4, &res) == 0)
+ src = FIB_RES_PREFSRC(dev_net(rt->dst.dev), res);
+ else
+ src = inet_select_addr(rt->dst.dev, rt->rt_gateway,
+ RT_SCOPE_UNIVERSE);
+ rcu_read_unlock();
+ }
+ memcpy(addr, &src, 4);
+}
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+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_mtu(const struct dst_entry *dst)
+{
+ const struct rtable *rt = (const struct rtable *) dst;
+ unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
+
+ if (mtu && rt_is_output_route(rt))
+ return mtu;
+
+ mtu = dst->dev->mtu;
+
+ if (unlikely(dst_metric_locked(dst, RTAX_MTU))) {
+
+ 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_init_metrics(struct rtable *rt, const struct flowi4 *fl4,
+ struct fib_info *fi)
+{
+ struct inet_peer *peer;
+ int create = 0;
+
+ /* If a peer entry exists for this destination, we must hook
+ * it up in order to get at cached metrics.
+ */
+ if (fl4 && (fl4->flowi4_flags & FLOWI_FLAG_PRECOW_METRICS))
+ create = 1;
+
+ rt->peer = peer = inet_getpeer_v4(rt->rt_dst, create);
+ if (peer) {
+ rt->rt_peer_genid = rt_peer_genid();
+ if (inet_metrics_new(peer))
+ memcpy(peer->metrics, fi->fib_metrics,
+ sizeof(u32) * RTAX_MAX);
+ dst_init_metrics(&rt->dst, peer->metrics, false);
+
+ check_peer_pmtu(&rt->dst, peer);
+
+ if (peer->redirect_learned.a4 &&
+ peer->redirect_learned.a4 != rt->rt_gateway) {
+ rt->rt_gateway = peer->redirect_learned.a4;
+ rt->rt_flags |= RTCF_REDIRECTED;
+ }
+ } else {
+ if (fi->fib_metrics != (u32 *) dst_default_metrics) {
+ rt->fi = fi;
+ atomic_inc(&fi->fib_clntref);
+ }
+ dst_init_metrics(&rt->dst, fi->fib_metrics, true);
+ }
+}
+
+static void rt_set_nexthop(struct rtable *rt, const struct flowi4 *fl4,
+ const struct fib_result *res,
+ struct fib_info *fi, u16 type, u32 itag)
+{
+ struct dst_entry *dst = &rt->dst;
+
+ if (fi) {
+ if (FIB_RES_GW(*res) &&
+ FIB_RES_NH(*res).nh_scope == RT_SCOPE_LINK)
+ rt->rt_gateway = FIB_RES_GW(*res);
+ net_run_track(PRT_NEXTHOP,"rt_set_nexthop");
+ rt_init_metrics(rt, fl4, fi);
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ 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_IP_ROUTE_CLASSID
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+ set_class_tag(rt, fib_rules_tclass(res));
+#endif
+ set_class_tag(rt, itag);
+#endif
+}
+
+static struct rtable *rt_dst_alloc(struct net_device *dev,
+ bool nopolicy, bool noxfrm)
+{
+ return dst_alloc(&ipv4_dst_ops, dev, 1, -1,
+ DST_HOST |
+ (nopolicy ? DST_NOPOLICY : 0) |
+ (noxfrm ? DST_NOXFRM : 0));
+}
+
+/* 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(skb, saddr, 0, tos, 0, dev, &spec_dst,
+ &itag);
+ if (err < 0)
+ goto e_err;
+ }
+ rth = rt_dst_alloc(dev_net(dev)->loopback_dev,
+ IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
+ if (!rth)
+ goto e_nobufs;
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ rth->dst.tclassid = itag;
+#endif
+ rth->dst.output = ip_rt_bug;
+
+ rth->rt_key_dst = daddr;
+ rth->rt_key_src = saddr;
+ rth->rt_genid = rt_genid(dev_net(dev));
+ rth->rt_flags = RTCF_MULTICAST;
+ rth->rt_type = RTN_MULTICAST;
+ rth->rt_key_tos = tos;
+ rth->rt_dst = daddr;
+ rth->rt_src = saddr;
+ rth->rt_route_iif = dev->ifindex;
+ rth->rt_iif = dev->ifindex;
+ rth->rt_oif = 0;
+ rth->rt_mark = skb->mark;
+ rth->rt_gateway = daddr;
+ rth->rt_spec_dst= spec_dst;
+ rth->rt_peer_genid = 0;
+ rth->peer = NULL;
+ rth->fi = NULL;
+ 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)));
+ rth = rt_intern_hash(hash, rth, skb, dev->ifindex);
+ return IS_ERR(rth) ? PTR_ERR(rth) : 0;
+
+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.
+ */
+ pr_warn("martian source %pI4 from %pI4, on dev %s\n",
+ &daddr, &saddr, dev->name);
+ if (dev->hard_header_len && skb_mac_header_was_set(skb)) {
+ print_hex_dump(KERN_WARNING, "ll header: ",
+ DUMP_PREFIX_OFFSET, 16, 1,
+ skb_mac_header(skb),
+ dev->hard_header_len, true);
+ }
+ }
+#endif
+}
+
+/* called in rcu_read_lock() section */
+static int __mkroute_input(struct sk_buff *skb,
+ const 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 = 0;
+
+ /* 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())
+ pr_crit("Bug in ip_route_input_slow(). Please report.\n");
+ return -EINVAL;
+ }
+
+
+ err = fib_validate_source(skb, saddr, daddr, tos, FIB_RES_OIF(*res),
+ in_dev->dev, &spec_dst, &itag);
+ 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_TX_REDIRECTS(out_dev) &&
+ skb->protocol == htons(ETH_P_IP) &&
+ (IN_DEV_SHARED_MEDIA(out_dev) ||
+ inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
+ IPCB(skb)->flags |= IPSKB_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 = rt_dst_alloc(out_dev->dev,
+ IN_DEV_CONF_GET(in_dev, NOPOLICY),
+ IN_DEV_CONF_GET(out_dev, NOXFRM));
+ if (!rth) {
+ err = -ENOBUFS;
+ goto cleanup;
+ }
+
+ rth->rt_key_dst = daddr;
+ rth->rt_key_src = saddr;
+ rth->rt_genid = rt_genid(dev_net(rth->dst.dev));
+ rth->rt_flags = flags;
+ rth->rt_type = res->type;
+ rth->rt_key_tos = tos;
+ rth->rt_dst = daddr;
+ rth->rt_src = saddr;
+ rth->rt_route_iif = in_dev->dev->ifindex;
+ rth->rt_iif = in_dev->dev->ifindex;
+ rth->rt_oif = 0;
+ rth->rt_mark = skb->mark;
+ rth->rt_gateway = daddr;
+ rth->rt_spec_dst= spec_dst;
+ rth->rt_peer_genid = 0;
+ rth->peer = NULL;
+ rth->fi = NULL;
+
+ rth->dst.input = ip_forward;
+ rth->dst.output = ip_output;
+
+ rt_set_nexthop(rth, NULL, res, res->fi, res->type, itag);
+
+ *result = rth;
+ err = 0;
+ cleanup:
+ return err;
+}
+
+static int ip_mkroute_input(struct sk_buff *skb,
+ struct fib_result *res,
+ const struct flowi4 *fl4,
+ 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)
+ fib_select_multipath(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, fl4->flowi4_iif,
+ rt_genid(dev_net(rth->dst.dev)));
+ rth = rt_intern_hash(hash, rth, skb, fl4->flowi4_iif);
+ if (IS_ERR(rth))
+ return PTR_ERR(rth);
+ return 0;
+}
+
+/*
+ * 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 flowi4 fl4;
+ 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.
+ */
+ fl4.flowi4_oif = 0;
+ fl4.flowi4_iif = dev->ifindex;
+ fl4.flowi4_mark = skb->mark;
+ fl4.flowi4_tos = tos;
+ fl4.flowi4_scope = RT_SCOPE_UNIVERSE;
+ fl4.daddr = daddr;
+ fl4.saddr = saddr;
+ err = fib_lookup(net, &fl4, &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(skb, saddr, daddr, tos,
+ net->loopback_dev->ifindex,
+ dev, &spec_dst, &itag);
+ 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, &fl4, in_dev, daddr, saddr, tos);
+out:
+ net_run_track(PRT_ROUTE," route err = %d",err);
+ 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(skb, saddr, 0, tos, 0, dev, &spec_dst,
+ &itag);
+ 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 = rt_dst_alloc(net->loopback_dev,
+ IN_DEV_CONF_GET(in_dev, NOPOLICY), false);
+ if (!rth)
+ goto e_nobufs;
+
+ rth->dst.input= ip_local_deliver;
+ rth->dst.output= ip_rt_bug;
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ rth->dst.tclassid = itag;
+#endif
+
+ rth->rt_key_dst = daddr;
+ rth->rt_key_src = saddr;
+ rth->rt_genid = rt_genid(net);
+ rth->rt_flags = flags|RTCF_LOCAL;
+ rth->rt_type = res.type;
+ rth->rt_key_tos = tos;
+ rth->rt_dst = daddr;
+ rth->rt_src = saddr;
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ rth->dst.tclassid = itag;
+#endif
+ rth->rt_route_iif = dev->ifindex;
+ rth->rt_iif = dev->ifindex;
+ rth->rt_oif = 0;
+ rth->rt_mark = skb->mark;
+ rth->rt_gateway = daddr;
+ rth->rt_spec_dst= spec_dst;
+ rth->rt_peer_genid = 0;
+ rth->peer = NULL;
+ rth->fi = NULL;
+ if (res.type == RTN_UNREACHABLE) {
+ rth->dst.input= ip_error;
+ rth->dst.error= -err;
+ rth->rt_flags &= ~RTCF_LOCAL;
+ }
+ hash = rt_hash(daddr, saddr, fl4.flowi4_iif, rt_genid(net));
+ rth = rt_intern_hash(hash, rth, skb, fl4.flowi4_iif);
+ err = 0;
+ if (IS_ERR(rth))
+ err = PTR_ERR(rth);
+ 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())
+ pr_warn("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->rt_key_dst ^ (__force u32)daddr) |
+ ((__force u32)rth->rt_key_src ^ (__force u32)saddr) |
+ (rth->rt_route_iif ^ iif) |
+ (rth->rt_key_tos ^ tos)) == 0 &&
+ rth->rt_mark == skb->mark &&
+ net_eq(dev_net(rth->dst.dev), net) &&
+ !rt_is_expired(rth)) {
+ ipv4_validate_peer(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_rcu(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();
+ net_run_track(PRT_ROUTE," route");
+ return res;
+ }
+ }
+ rcu_read_unlock();
+ return -EINVAL;
+ }
+ res = ip_route_input_slow(skb, daddr, saddr, tos, dev);
+ rcu_read_unlock();
+ net_run_track(PRT_ROUTE," route");
+ return res;
+}
+EXPORT_SYMBOL(ip_route_input_common);
+
+/* called with rcu_read_lock() */
+static struct rtable *__mkroute_output(const struct fib_result *res,
+ const struct flowi4 *fl4,
+ __be32 orig_daddr, __be32 orig_saddr,
+ int orig_oif, __u8 orig_rtos,
+ struct net_device *dev_out,
+ unsigned int flags)
+{
+ struct fib_info *fi = res->fi;
+ struct in_device *in_dev;
+ u16 type = res->type;
+ struct rtable *rth;
+
+ if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK))
+ return ERR_PTR(-EINVAL);
+
+ if (ipv4_is_lbcast(fl4->daddr))
+ type = RTN_BROADCAST;
+ else if (ipv4_is_multicast(fl4->daddr))
+ type = RTN_MULTICAST;
+ else if (ipv4_is_zeronet(fl4->daddr))
+ return ERR_PTR(-EINVAL);
+
+ if (dev_out->flags & IFF_LOOPBACK)
+ flags |= RTCF_LOCAL;
+
+ in_dev = __in_dev_get_rcu(dev_out);
+ if (!in_dev)
+ return ERR_PTR(-EINVAL);
+
+ if (type == RTN_BROADCAST) {
+ flags |= RTCF_BROADCAST | RTCF_LOCAL;
+ fi = NULL;
+ } else if (type == RTN_MULTICAST) {
+ flags |= RTCF_MULTICAST | RTCF_LOCAL;
+ if (!ip_check_mc_rcu(in_dev, fl4->daddr, fl4->saddr,
+ fl4->flowi4_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 (fi && res->prefixlen < 4)
+ fi = NULL;
+ }
+
+ rth = rt_dst_alloc(dev_out,
+ IN_DEV_CONF_GET(in_dev, NOPOLICY),
+ IN_DEV_CONF_GET(in_dev, NOXFRM));
+ if (!rth)
+ return ERR_PTR(-ENOBUFS);
+
+ rth->dst.output = ip_output;
+
+ rth->rt_key_dst = orig_daddr;
+ rth->rt_key_src = orig_saddr;
+ rth->rt_genid = rt_genid(dev_net(dev_out));
+ rth->rt_flags = flags;
+ rth->rt_type = type;
+ rth->rt_key_tos = orig_rtos;
+ rth->rt_dst = fl4->daddr;
+ rth->rt_src = fl4->saddr;
+ rth->rt_route_iif = 0;
+ rth->rt_iif = orig_oif ? : dev_out->ifindex;
+ rth->rt_oif = orig_oif;
+ rth->rt_mark = fl4->flowi4_mark;
+ rth->rt_gateway = fl4->daddr;
+ rth->rt_spec_dst= fl4->saddr;
+ rth->rt_peer_genid = 0;
+ rth->peer = NULL;
+ rth->fi = NULL;
+
+ RT_CACHE_STAT_INC(out_slow_tot);
+
+ if (flags & RTCF_LOCAL) {
+ rth->dst.input = ip_local_deliver;
+ rth->rt_spec_dst = fl4->daddr;
+ }
+ if (flags & (RTCF_BROADCAST | RTCF_MULTICAST)) {
+ rth->rt_spec_dst = fl4->saddr;
+ 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 (type == RTN_MULTICAST) {
+ if (IN_DEV_MFORWARD(in_dev) &&
+ !ipv4_is_local_multicast(fl4->daddr)) {
+ rth->dst.input = ip_mr_input;
+ rth->dst.output = ip_mc_output;
+ }
+ }
+#endif
+ }
+
+ rt_set_nexthop(rth, fl4, res, fi, type, 0);
+
+ return rth;
+}
+
+/*
+ * Major route resolver routine.
+ * called with rcu_read_lock();
+ */
+
+static struct rtable *ip_route_output_slow(struct net *net, struct flowi4 *fl4)
+{
+ struct net_device *dev_out = NULL;
+ __u8 tos = RT_FL_TOS(fl4);
+ unsigned int flags = 0;
+ struct fib_result res;
+ struct rtable *rth;
+ __be32 orig_daddr;
+ __be32 orig_saddr;
+ int orig_oif;
+
+ res.fi = NULL;
+#ifdef CONFIG_IP_MULTIPLE_TABLES
+ res.r = NULL;
+#endif
+
+ orig_daddr = fl4->daddr;
+ orig_saddr = fl4->saddr;
+ orig_oif = fl4->flowi4_oif;
+
+ fl4->flowi4_iif = net->loopback_dev->ifindex;
+ fl4->flowi4_tos = tos & IPTOS_RT_MASK;
+ fl4->flowi4_scope = ((tos & RTO_ONLINK) ?
+ RT_SCOPE_LINK : RT_SCOPE_UNIVERSE);
+
+ rcu_read_lock();
+ if (fl4->saddr) {
+ rth = ERR_PTR(-EINVAL);
+ if (ipv4_is_multicast(fl4->saddr) ||
+ ipv4_is_lbcast(fl4->saddr) ||
+ ipv4_is_zeronet(fl4->saddr))
+ 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 (fl4->flowi4_oif == 0 &&
+ (ipv4_is_multicast(fl4->daddr) ||
+ ipv4_is_lbcast(fl4->daddr))) {
+ /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
+ dev_out = __ip_dev_find(net, fl4->saddr, 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.
+ */
+
+ fl4->flowi4_oif = dev_out->ifindex;
+ goto make_route;
+ }
+
+ if (!(fl4->flowi4_flags & FLOWI_FLAG_ANYSRC)) {
+ /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */
+ if (!__ip_dev_find(net, fl4->saddr, false))
+ goto out;
+ }
+ }
+
+
+ if (fl4->flowi4_oif) {
+ dev_out = dev_get_by_index_rcu(net, fl4->flowi4_oif);
+ rth = ERR_PTR(-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)) {
+ rth = ERR_PTR(-ENETUNREACH);
+ goto out;
+ }
+ if (ipv4_is_local_multicast(fl4->daddr) ||
+ ipv4_is_lbcast(fl4->daddr)) {
+ if (!fl4->saddr)
+ fl4->saddr = inet_select_addr(dev_out, 0,
+ RT_SCOPE_LINK);
+ goto make_route;
+ }
+ if (!fl4->saddr) {
+ if (ipv4_is_multicast(fl4->daddr))
+ fl4->saddr = inet_select_addr(dev_out, 0,
+ fl4->flowi4_scope);
+ else if (!fl4->daddr)
+ fl4->saddr = inet_select_addr(dev_out, 0,
+ RT_SCOPE_HOST);
+ }
+ }
+
+ if (!fl4->daddr) {
+ fl4->daddr = fl4->saddr;
+ if (!fl4->daddr)
+ fl4->daddr = fl4->saddr = htonl(INADDR_LOOPBACK);
+ dev_out = net->loopback_dev;
+ fl4->flowi4_oif = net->loopback_dev->ifindex;
+ res.type = RTN_LOCAL;
+ net_run_track(PRT_ROUTE,"local route");
+ flags |= RTCF_LOCAL;
+ goto make_route;
+ }
+
+ if (fib_lookup(net, fl4, &res)) {
+ res.fi = NULL;
+ if (fl4->flowi4_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 (fl4->saddr == 0)
+ fl4->saddr = inet_select_addr(dev_out, 0,
+ RT_SCOPE_LINK);
+ res.type = RTN_UNICAST;
+ goto make_route;
+ }
+ rth = ERR_PTR(-ENETUNREACH);
+ goto out;
+ }
+
+ if (res.type == RTN_LOCAL) {
+ if (!fl4->saddr) {
+ if (res.fi->fib_prefsrc)
+ fl4->saddr = res.fi->fib_prefsrc;
+ else
+ fl4->saddr = fl4->daddr;
+ }
+ dev_out = net->loopback_dev;
+ fl4->flowi4_oif = dev_out->ifindex;
+ res.fi = NULL;
+ flags |= RTCF_LOCAL;
+ goto make_route;
+ }
+
+#ifdef CONFIG_IP_ROUTE_MULTIPATH
+ if (res.fi->fib_nhs > 1 && fl4->flowi4_oif == 0)
+ fib_select_multipath(&res);
+ else
+#endif
+ if (!res.prefixlen &&
+ res.table->tb_num_default > 1 &&
+ res.type == RTN_UNICAST && !fl4->flowi4_oif)
+ fib_select_default(&res);
+
+ if (!fl4->saddr)
+ fl4->saddr = FIB_RES_PREFSRC(net, res);
+
+ dev_out = FIB_RES_DEV(res);
+ fl4->flowi4_oif = dev_out->ifindex;
+
+
+make_route:
+ rth = __mkroute_output(&res, fl4, orig_daddr, orig_saddr, orig_oif,
+ tos, dev_out, flags);
+ if (!IS_ERR(rth)) {
+ unsigned int hash;
+
+ hash = rt_hash(orig_daddr, orig_saddr, orig_oif,
+ rt_genid(dev_net(dev_out)));
+ rth = rt_intern_hash(hash, rth, NULL, orig_oif);
+ }
+
+out:
+ rcu_read_unlock();
+ return rth;
+}
+
+struct rtable *__ip_route_output_key(struct net *net, struct flowi4 *flp4)
+{
+ struct rtable *rth;
+ unsigned int hash;
+
+ if (!rt_caching(net))
+ goto slow_output;
+
+ hash = rt_hash(flp4->daddr, flp4->saddr, flp4->flowi4_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->rt_key_dst == flp4->daddr &&
+ rth->rt_key_src == flp4->saddr &&
+ rt_is_output_route(rth) &&
+ rth->rt_oif == flp4->flowi4_oif &&
+ rth->rt_mark == flp4->flowi4_mark &&
+ !((rth->rt_key_tos ^ flp4->flowi4_tos) &
+ (IPTOS_RT_MASK | RTO_ONLINK)) &&
+ net_eq(dev_net(rth->dst.dev), net) &&
+ !rt_is_expired(rth)) {
+ ipv4_validate_peer(rth);
+ dst_use(&rth->dst, jiffies);
+ RT_CACHE_STAT_INC(out_hit);
+ rcu_read_unlock_bh();
+ if (!flp4->saddr)
+ flp4->saddr = rth->rt_src;
+ if (!flp4->daddr)
+ flp4->daddr = rth->rt_dst;
+ net_run_track(PRT_ROUTE," route");
+ return rth;
+ }
+ RT_CACHE_STAT_INC(out_hlist_search);
+ }
+ rcu_read_unlock_bh();
+
+slow_output:
+ return ip_route_output_slow(net, flp4);
+}
+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_mtu(const struct dst_entry *dst)
+{
+ unsigned int mtu = dst_metric_raw(dst, RTAX_MTU);
+
+ return mtu ? : dst->dev->mtu;
+}
+
+static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
+{
+}
+
+static u32 *ipv4_rt_blackhole_cow_metrics(struct dst_entry *dst,
+ unsigned long old)
+{
+ return NULL;
+}
+
+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,
+ .mtu = ipv4_blackhole_mtu,
+ .default_advmss = ipv4_default_advmss,
+ .update_pmtu = ipv4_rt_blackhole_update_pmtu,
+ .cow_metrics = ipv4_rt_blackhole_cow_metrics,
+ .neigh_lookup = ipv4_neigh_lookup,
+};
+
+struct dst_entry *ipv4_blackhole_route(struct net *net, struct dst_entry *dst_orig)
+{
+ struct rtable *rt = dst_alloc(&ipv4_dst_blackhole_ops, NULL, 1, 0, 0);
+ struct rtable *ort = (struct rtable *) dst_orig;
+
+ if (rt) {
+ struct dst_entry *new = &rt->dst;
+
+ 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->rt_key_dst = ort->rt_key_dst;
+ rt->rt_key_src = ort->rt_key_src;
+ rt->rt_key_tos = ort->rt_key_tos;
+ rt->rt_route_iif = ort->rt_route_iif;
+ rt->rt_iif = ort->rt_iif;
+ rt->rt_oif = ort->rt_oif;
+ rt->rt_mark = ort->rt_mark;
+
+ 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_gateway = ort->rt_gateway;
+ rt->rt_spec_dst = ort->rt_spec_dst;
+ rt->peer = ort->peer;
+ if (rt->peer)
+ atomic_inc(&rt->peer->refcnt);
+ rt->fi = ort->fi;
+ if (rt->fi)
+ atomic_inc(&rt->fi->fib_clntref);
+
+ dst_free(new);
+ }
+
+ dst_release(dst_orig);
+
+ return rt ? &rt->dst : ERR_PTR(-ENOMEM);
+}
+
+struct rtable *ip_route_output_flow(struct net *net, struct flowi4 *flp4,
+ struct sock *sk)
+{
+ struct rtable *rt = __ip_route_output_key(net, flp4);
+
+ if (IS_ERR(rt))
+ return rt;
+
+ if (flp4->flowi4_proto)
+ rt = (struct rtable *) xfrm_lookup(net, &rt->dst,
+ flowi4_to_flowi(flp4),
+ sk, 0);
+
+ return rt;
+}
+EXPORT_SYMBOL_GPL(ip_route_output_flow);
+
+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;
+ unsigned long expires = 0;
+ const struct inet_peer *peer = rt->peer;
+ 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->rt_key_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;
+ if (IPCB(skb)->flags & IPSKB_DOREDIRECT)
+ r->rtm_flags |= RTCF_DOREDIRECT;
+
+ NLA_PUT_BE32(skb, RTA_DST, rt->rt_dst);
+
+ if (rt->rt_key_src) {
+ r->rtm_src_len = 32;
+ NLA_PUT_BE32(skb, RTA_SRC, rt->rt_key_src);
+ }
+ if (rt->dst.dev)
+ NLA_PUT_U32(skb, RTA_OIF, rt->dst.dev->ifindex);
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ 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->rt_key_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->rt_mark)
+ NLA_PUT_BE32(skb, RTA_MARK, rt->rt_mark);
+
+ error = rt->dst.error;
+ if (peer) {
+ inet_peer_refcheck(rt->peer);
+ if (peer->tcp_ts_stamp) {
+ ts = peer->tcp_ts;
+ tsage = get_seconds() - peer->tcp_ts_stamp;
+ }
+ expires = ACCESS_ONCE(peer->pmtu_expires);
+ if (expires) {
+ if (time_before(jiffies, expires))
+ expires -= jiffies;
+ else
+ expires = 0;
+ }
+ }
+
+ 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,
+ rt->rt_src, rt->rt_dst,
+ 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->rt_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 flowi4 fl4 = {
+ .daddr = dst,
+ .saddr = src,
+ .flowi4_tos = rtm->rtm_tos,
+ .flowi4_oif = tb[RTA_OIF] ? nla_get_u32(tb[RTA_OIF]) : 0,
+ .flowi4_mark = mark,
+ };
+ rt = ip_route_output_key(net, &fl4);
+
+ err = 0;
+ if (IS_ERR(rt))
+ err = PTR_ERR(rt);
+ }
+
+ 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));
+ get_random_bytes(&net->ipv4.dev_addr_genid,
+ sizeof(net->ipv4.dev_addr_genid));
+ return 0;
+}
+
+static __net_initdata struct pernet_operations rt_genid_ops = {
+ .init = rt_genid_init,
+};
+
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+struct ip_rt_acct __percpu *ip_rt_acct __read_mostly;
+#endif /* CONFIG_IP_ROUTE_CLASSID */
+
+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;
+
+ ip_idents = kmalloc(IP_IDENTS_SZ * sizeof(*ip_idents), GFP_KERNEL);
+ if (!ip_idents)
+ panic("IP: failed to allocate ip_idents\n");
+
+ get_random_bytes(ip_idents, IP_IDENTS_SZ * sizeof(*ip_idents));
+
+#ifdef CONFIG_IP_ROUTE_CLASSID
+ 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();
+
+ 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())
+ pr_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, 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