![David Ahern](/assets/img/avatar_default.png)
Move call to call_fib6_entry_notifiers for new IPv6 routes to right before the insertion into the FIB. At this point notifier handlers can decide the fate of the new route with a clean path to delete the potential new entry if the notifier returns non-0. Signed-off-by: David Ahern <dsa@cumulusnetworks.com> Reviewed-by: Ido Schimmel <idosch@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2400 lines
55 KiB
C
2400 lines
55 KiB
C
/*
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* Linux INET6 implementation
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* Forwarding Information Database
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*
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* Authors:
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* Pedro Roque <roque@di.fc.ul.pt>
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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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* Changes:
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* Yuji SEKIYA @USAGI: Support default route on router node;
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* remove ip6_null_entry from the top of
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* routing table.
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* Ville Nuorvala: Fixed routing subtrees.
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*/
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#define pr_fmt(fmt) "IPv6: " fmt
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/net.h>
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#include <linux/route.h>
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#include <linux/netdevice.h>
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#include <linux/in6.h>
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#include <linux/init.h>
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#include <linux/list.h>
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#include <linux/slab.h>
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#include <net/ipv6.h>
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#include <net/ndisc.h>
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#include <net/addrconf.h>
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#include <net/lwtunnel.h>
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#include <net/fib_notifier.h>
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#include <net/ip6_fib.h>
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#include <net/ip6_route.h>
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static struct kmem_cache *fib6_node_kmem __read_mostly;
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struct fib6_cleaner {
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struct fib6_walker w;
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struct net *net;
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int (*func)(struct rt6_info *, void *arg);
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int sernum;
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void *arg;
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};
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#ifdef CONFIG_IPV6_SUBTREES
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#define FWS_INIT FWS_S
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#else
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#define FWS_INIT FWS_L
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#endif
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static struct rt6_info *fib6_find_prefix(struct net *net,
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struct fib6_table *table,
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struct fib6_node *fn);
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static struct fib6_node *fib6_repair_tree(struct net *net,
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struct fib6_table *table,
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struct fib6_node *fn);
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static int fib6_walk(struct net *net, struct fib6_walker *w);
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static int fib6_walk_continue(struct fib6_walker *w);
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/*
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* A routing update causes an increase of the serial number on the
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* affected subtree. This allows for cached routes to be asynchronously
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* tested when modifications are made to the destination cache as a
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* result of redirects, path MTU changes, etc.
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*/
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static void fib6_gc_timer_cb(struct timer_list *t);
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#define FOR_WALKERS(net, w) \
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list_for_each_entry(w, &(net)->ipv6.fib6_walkers, lh)
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static void fib6_walker_link(struct net *net, struct fib6_walker *w)
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{
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write_lock_bh(&net->ipv6.fib6_walker_lock);
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list_add(&w->lh, &net->ipv6.fib6_walkers);
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write_unlock_bh(&net->ipv6.fib6_walker_lock);
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}
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static void fib6_walker_unlink(struct net *net, struct fib6_walker *w)
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{
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write_lock_bh(&net->ipv6.fib6_walker_lock);
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list_del(&w->lh);
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write_unlock_bh(&net->ipv6.fib6_walker_lock);
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}
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static int fib6_new_sernum(struct net *net)
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{
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int new, old;
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do {
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old = atomic_read(&net->ipv6.fib6_sernum);
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new = old < INT_MAX ? old + 1 : 1;
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} while (atomic_cmpxchg(&net->ipv6.fib6_sernum,
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old, new) != old);
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return new;
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}
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enum {
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FIB6_NO_SERNUM_CHANGE = 0,
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};
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void fib6_update_sernum(struct rt6_info *rt)
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{
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struct net *net = dev_net(rt->dst.dev);
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struct fib6_node *fn;
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fn = rcu_dereference_protected(rt->rt6i_node,
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lockdep_is_held(&rt->rt6i_table->tb6_lock));
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if (fn)
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fn->fn_sernum = fib6_new_sernum(net);
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}
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/*
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* Auxiliary address test functions for the radix tree.
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*
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* These assume a 32bit processor (although it will work on
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* 64bit processors)
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*/
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/*
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* test bit
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*/
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#if defined(__LITTLE_ENDIAN)
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# define BITOP_BE32_SWIZZLE (0x1F & ~7)
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#else
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# define BITOP_BE32_SWIZZLE 0
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#endif
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static __be32 addr_bit_set(const void *token, int fn_bit)
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{
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const __be32 *addr = token;
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/*
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* Here,
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* 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)
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* is optimized version of
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* htonl(1 << ((~fn_bit)&0x1F))
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* See include/asm-generic/bitops/le.h.
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*/
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return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) &
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addr[fn_bit >> 5];
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}
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static struct fib6_node *node_alloc(struct net *net)
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{
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struct fib6_node *fn;
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fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC);
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if (fn)
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net->ipv6.rt6_stats->fib_nodes++;
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return fn;
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}
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static void node_free_immediate(struct net *net, struct fib6_node *fn)
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{
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kmem_cache_free(fib6_node_kmem, fn);
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net->ipv6.rt6_stats->fib_nodes--;
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}
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static void node_free_rcu(struct rcu_head *head)
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{
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struct fib6_node *fn = container_of(head, struct fib6_node, rcu);
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kmem_cache_free(fib6_node_kmem, fn);
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}
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static void node_free(struct net *net, struct fib6_node *fn)
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{
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call_rcu(&fn->rcu, node_free_rcu);
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net->ipv6.rt6_stats->fib_nodes--;
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}
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void rt6_free_pcpu(struct rt6_info *non_pcpu_rt)
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{
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int cpu;
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if (!non_pcpu_rt->rt6i_pcpu)
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return;
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for_each_possible_cpu(cpu) {
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struct rt6_info **ppcpu_rt;
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struct rt6_info *pcpu_rt;
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ppcpu_rt = per_cpu_ptr(non_pcpu_rt->rt6i_pcpu, cpu);
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pcpu_rt = *ppcpu_rt;
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if (pcpu_rt) {
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dst_dev_put(&pcpu_rt->dst);
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dst_release(&pcpu_rt->dst);
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*ppcpu_rt = NULL;
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}
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}
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}
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EXPORT_SYMBOL_GPL(rt6_free_pcpu);
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static void fib6_free_table(struct fib6_table *table)
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{
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inetpeer_invalidate_tree(&table->tb6_peers);
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kfree(table);
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}
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static void fib6_link_table(struct net *net, struct fib6_table *tb)
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{
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unsigned int h;
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/*
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* Initialize table lock at a single place to give lockdep a key,
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* tables aren't visible prior to being linked to the list.
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*/
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spin_lock_init(&tb->tb6_lock);
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h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1);
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/*
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* No protection necessary, this is the only list mutatation
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* operation, tables never disappear once they exist.
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*/
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hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]);
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}
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#ifdef CONFIG_IPV6_MULTIPLE_TABLES
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static struct fib6_table *fib6_alloc_table(struct net *net, u32 id)
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{
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struct fib6_table *table;
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table = kzalloc(sizeof(*table), GFP_ATOMIC);
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if (table) {
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table->tb6_id = id;
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rcu_assign_pointer(table->tb6_root.leaf,
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net->ipv6.ip6_null_entry);
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table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
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inet_peer_base_init(&table->tb6_peers);
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}
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return table;
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}
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struct fib6_table *fib6_new_table(struct net *net, u32 id)
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{
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struct fib6_table *tb;
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if (id == 0)
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id = RT6_TABLE_MAIN;
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tb = fib6_get_table(net, id);
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if (tb)
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return tb;
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tb = fib6_alloc_table(net, id);
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if (tb)
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fib6_link_table(net, tb);
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return tb;
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}
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EXPORT_SYMBOL_GPL(fib6_new_table);
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struct fib6_table *fib6_get_table(struct net *net, u32 id)
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{
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struct fib6_table *tb;
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struct hlist_head *head;
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unsigned int h;
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if (id == 0)
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id = RT6_TABLE_MAIN;
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h = id & (FIB6_TABLE_HASHSZ - 1);
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rcu_read_lock();
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head = &net->ipv6.fib_table_hash[h];
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hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
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if (tb->tb6_id == id) {
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rcu_read_unlock();
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return tb;
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}
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}
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rcu_read_unlock();
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return NULL;
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}
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EXPORT_SYMBOL_GPL(fib6_get_table);
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static void __net_init fib6_tables_init(struct net *net)
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{
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fib6_link_table(net, net->ipv6.fib6_main_tbl);
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fib6_link_table(net, net->ipv6.fib6_local_tbl);
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}
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#else
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struct fib6_table *fib6_new_table(struct net *net, u32 id)
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{
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return fib6_get_table(net, id);
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}
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struct fib6_table *fib6_get_table(struct net *net, u32 id)
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{
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return net->ipv6.fib6_main_tbl;
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}
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struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
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const struct sk_buff *skb,
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int flags, pol_lookup_t lookup)
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{
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struct rt6_info *rt;
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rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags);
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if (rt->dst.error == -EAGAIN) {
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ip6_rt_put(rt);
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rt = net->ipv6.ip6_null_entry;
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dst_hold(&rt->dst);
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}
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return &rt->dst;
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}
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static void __net_init fib6_tables_init(struct net *net)
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{
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fib6_link_table(net, net->ipv6.fib6_main_tbl);
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}
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#endif
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unsigned int fib6_tables_seq_read(struct net *net)
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{
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unsigned int h, fib_seq = 0;
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rcu_read_lock();
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for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
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struct hlist_head *head = &net->ipv6.fib_table_hash[h];
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struct fib6_table *tb;
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hlist_for_each_entry_rcu(tb, head, tb6_hlist)
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fib_seq += tb->fib_seq;
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}
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rcu_read_unlock();
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return fib_seq;
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}
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static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net,
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enum fib_event_type event_type,
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struct rt6_info *rt)
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{
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struct fib6_entry_notifier_info info = {
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.rt = rt,
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};
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return call_fib6_notifier(nb, net, event_type, &info.info);
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}
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static int call_fib6_entry_notifiers(struct net *net,
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enum fib_event_type event_type,
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struct rt6_info *rt,
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struct netlink_ext_ack *extack)
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{
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struct fib6_entry_notifier_info info = {
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.info.extack = extack,
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.rt = rt,
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};
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rt->rt6i_table->fib_seq++;
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return call_fib6_notifiers(net, event_type, &info.info);
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}
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struct fib6_dump_arg {
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struct net *net;
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struct notifier_block *nb;
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};
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static void fib6_rt_dump(struct rt6_info *rt, struct fib6_dump_arg *arg)
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{
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if (rt == arg->net->ipv6.ip6_null_entry)
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return;
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call_fib6_entry_notifier(arg->nb, arg->net, FIB_EVENT_ENTRY_ADD, rt);
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}
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static int fib6_node_dump(struct fib6_walker *w)
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{
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struct rt6_info *rt;
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for_each_fib6_walker_rt(w)
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fib6_rt_dump(rt, w->args);
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w->leaf = NULL;
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return 0;
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}
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static void fib6_table_dump(struct net *net, struct fib6_table *tb,
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struct fib6_walker *w)
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{
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w->root = &tb->tb6_root;
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spin_lock_bh(&tb->tb6_lock);
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fib6_walk(net, w);
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spin_unlock_bh(&tb->tb6_lock);
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}
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/* Called with rcu_read_lock() */
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int fib6_tables_dump(struct net *net, struct notifier_block *nb)
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{
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struct fib6_dump_arg arg;
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struct fib6_walker *w;
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unsigned int h;
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w = kzalloc(sizeof(*w), GFP_ATOMIC);
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if (!w)
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return -ENOMEM;
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w->func = fib6_node_dump;
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arg.net = net;
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arg.nb = nb;
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w->args = &arg;
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for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
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struct hlist_head *head = &net->ipv6.fib_table_hash[h];
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struct fib6_table *tb;
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hlist_for_each_entry_rcu(tb, head, tb6_hlist)
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fib6_table_dump(net, tb, w);
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}
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kfree(w);
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return 0;
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}
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static int fib6_dump_node(struct fib6_walker *w)
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{
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int res;
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struct rt6_info *rt;
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for_each_fib6_walker_rt(w) {
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res = rt6_dump_route(rt, w->args);
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if (res < 0) {
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/* Frame is full, suspend walking */
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w->leaf = rt;
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return 1;
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}
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/* Multipath routes are dumped in one route with the
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* RTA_MULTIPATH attribute. Jump 'rt' to point to the
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* last sibling of this route (no need to dump the
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* sibling routes again)
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*/
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if (rt->rt6i_nsiblings)
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rt = list_last_entry(&rt->rt6i_siblings,
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struct rt6_info,
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rt6i_siblings);
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}
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w->leaf = NULL;
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return 0;
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}
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static void fib6_dump_end(struct netlink_callback *cb)
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{
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struct net *net = sock_net(cb->skb->sk);
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struct fib6_walker *w = (void *)cb->args[2];
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if (w) {
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if (cb->args[4]) {
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cb->args[4] = 0;
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fib6_walker_unlink(net, w);
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}
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cb->args[2] = 0;
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kfree(w);
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}
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cb->done = (void *)cb->args[3];
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cb->args[1] = 3;
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}
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static int fib6_dump_done(struct netlink_callback *cb)
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{
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fib6_dump_end(cb);
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return cb->done ? cb->done(cb) : 0;
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}
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static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb,
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struct netlink_callback *cb)
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{
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struct net *net = sock_net(skb->sk);
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struct fib6_walker *w;
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int res;
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w = (void *)cb->args[2];
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w->root = &table->tb6_root;
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if (cb->args[4] == 0) {
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w->count = 0;
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w->skip = 0;
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spin_lock_bh(&table->tb6_lock);
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res = fib6_walk(net, w);
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spin_unlock_bh(&table->tb6_lock);
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if (res > 0) {
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cb->args[4] = 1;
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cb->args[5] = w->root->fn_sernum;
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}
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} else {
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if (cb->args[5] != w->root->fn_sernum) {
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/* Begin at the root if the tree changed */
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cb->args[5] = w->root->fn_sernum;
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w->state = FWS_INIT;
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w->node = w->root;
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w->skip = w->count;
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} else
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w->skip = 0;
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spin_lock_bh(&table->tb6_lock);
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res = fib6_walk_continue(w);
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spin_unlock_bh(&table->tb6_lock);
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if (res <= 0) {
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fib6_walker_unlink(net, w);
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cb->args[4] = 0;
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}
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}
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return res;
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}
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|
|
static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb)
|
|
{
|
|
struct net *net = sock_net(skb->sk);
|
|
unsigned int h, s_h;
|
|
unsigned int e = 0, s_e;
|
|
struct rt6_rtnl_dump_arg arg;
|
|
struct fib6_walker *w;
|
|
struct fib6_table *tb;
|
|
struct hlist_head *head;
|
|
int res = 0;
|
|
|
|
s_h = cb->args[0];
|
|
s_e = cb->args[1];
|
|
|
|
w = (void *)cb->args[2];
|
|
if (!w) {
|
|
/* New dump:
|
|
*
|
|
* 1. hook callback destructor.
|
|
*/
|
|
cb->args[3] = (long)cb->done;
|
|
cb->done = fib6_dump_done;
|
|
|
|
/*
|
|
* 2. allocate and initialize walker.
|
|
*/
|
|
w = kzalloc(sizeof(*w), GFP_ATOMIC);
|
|
if (!w)
|
|
return -ENOMEM;
|
|
w->func = fib6_dump_node;
|
|
cb->args[2] = (long)w;
|
|
}
|
|
|
|
arg.skb = skb;
|
|
arg.cb = cb;
|
|
arg.net = net;
|
|
w->args = &arg;
|
|
|
|
rcu_read_lock();
|
|
for (h = s_h; h < FIB6_TABLE_HASHSZ; h++, s_e = 0) {
|
|
e = 0;
|
|
head = &net->ipv6.fib_table_hash[h];
|
|
hlist_for_each_entry_rcu(tb, head, tb6_hlist) {
|
|
if (e < s_e)
|
|
goto next;
|
|
res = fib6_dump_table(tb, skb, cb);
|
|
if (res != 0)
|
|
goto out;
|
|
next:
|
|
e++;
|
|
}
|
|
}
|
|
out:
|
|
rcu_read_unlock();
|
|
cb->args[1] = e;
|
|
cb->args[0] = h;
|
|
|
|
res = res < 0 ? res : skb->len;
|
|
if (res <= 0)
|
|
fib6_dump_end(cb);
|
|
return res;
|
|
}
|
|
|
|
/*
|
|
* Routing Table
|
|
*
|
|
* return the appropriate node for a routing tree "add" operation
|
|
* by either creating and inserting or by returning an existing
|
|
* node.
|
|
*/
|
|
|
|
static struct fib6_node *fib6_add_1(struct net *net,
|
|
struct fib6_table *table,
|
|
struct fib6_node *root,
|
|
struct in6_addr *addr, int plen,
|
|
int offset, int allow_create,
|
|
int replace_required,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct fib6_node *fn, *in, *ln;
|
|
struct fib6_node *pn = NULL;
|
|
struct rt6key *key;
|
|
int bit;
|
|
__be32 dir = 0;
|
|
|
|
RT6_TRACE("fib6_add_1\n");
|
|
|
|
/* insert node in tree */
|
|
|
|
fn = root;
|
|
|
|
do {
|
|
struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
key = (struct rt6key *)((u8 *)leaf + offset);
|
|
|
|
/*
|
|
* Prefix match
|
|
*/
|
|
if (plen < fn->fn_bit ||
|
|
!ipv6_prefix_equal(&key->addr, addr, fn->fn_bit)) {
|
|
if (!allow_create) {
|
|
if (replace_required) {
|
|
NL_SET_ERR_MSG(extack,
|
|
"Can not replace route - no match found");
|
|
pr_warn("Can't replace route, no match found\n");
|
|
return ERR_PTR(-ENOENT);
|
|
}
|
|
pr_warn("NLM_F_CREATE should be set when creating new route\n");
|
|
}
|
|
goto insert_above;
|
|
}
|
|
|
|
/*
|
|
* Exact match ?
|
|
*/
|
|
|
|
if (plen == fn->fn_bit) {
|
|
/* clean up an intermediate node */
|
|
if (!(fn->fn_flags & RTN_RTINFO)) {
|
|
RCU_INIT_POINTER(fn->leaf, NULL);
|
|
rt6_release(leaf);
|
|
/* remove null_entry in the root node */
|
|
} else if (fn->fn_flags & RTN_TL_ROOT &&
|
|
rcu_access_pointer(fn->leaf) ==
|
|
net->ipv6.ip6_null_entry) {
|
|
RCU_INIT_POINTER(fn->leaf, NULL);
|
|
}
|
|
|
|
return fn;
|
|
}
|
|
|
|
/*
|
|
* We have more bits to go
|
|
*/
|
|
|
|
/* Try to walk down on tree. */
|
|
dir = addr_bit_set(addr, fn->fn_bit);
|
|
pn = fn;
|
|
fn = dir ?
|
|
rcu_dereference_protected(fn->right,
|
|
lockdep_is_held(&table->tb6_lock)) :
|
|
rcu_dereference_protected(fn->left,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
} while (fn);
|
|
|
|
if (!allow_create) {
|
|
/* We should not create new node because
|
|
* NLM_F_REPLACE was specified without NLM_F_CREATE
|
|
* I assume it is safe to require NLM_F_CREATE when
|
|
* REPLACE flag is used! Later we may want to remove the
|
|
* check for replace_required, because according
|
|
* to netlink specification, NLM_F_CREATE
|
|
* MUST be specified if new route is created.
|
|
* That would keep IPv6 consistent with IPv4
|
|
*/
|
|
if (replace_required) {
|
|
NL_SET_ERR_MSG(extack,
|
|
"Can not replace route - no match found");
|
|
pr_warn("Can't replace route, no match found\n");
|
|
return ERR_PTR(-ENOENT);
|
|
}
|
|
pr_warn("NLM_F_CREATE should be set when creating new route\n");
|
|
}
|
|
/*
|
|
* We walked to the bottom of tree.
|
|
* Create new leaf node without children.
|
|
*/
|
|
|
|
ln = node_alloc(net);
|
|
|
|
if (!ln)
|
|
return ERR_PTR(-ENOMEM);
|
|
ln->fn_bit = plen;
|
|
RCU_INIT_POINTER(ln->parent, pn);
|
|
|
|
if (dir)
|
|
rcu_assign_pointer(pn->right, ln);
|
|
else
|
|
rcu_assign_pointer(pn->left, ln);
|
|
|
|
return ln;
|
|
|
|
|
|
insert_above:
|
|
/*
|
|
* split since we don't have a common prefix anymore or
|
|
* we have a less significant route.
|
|
* we've to insert an intermediate node on the list
|
|
* this new node will point to the one we need to create
|
|
* and the current
|
|
*/
|
|
|
|
pn = rcu_dereference_protected(fn->parent,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
|
|
/* find 1st bit in difference between the 2 addrs.
|
|
|
|
See comment in __ipv6_addr_diff: bit may be an invalid value,
|
|
but if it is >= plen, the value is ignored in any case.
|
|
*/
|
|
|
|
bit = __ipv6_addr_diff(addr, &key->addr, sizeof(*addr));
|
|
|
|
/*
|
|
* (intermediate)[in]
|
|
* / \
|
|
* (new leaf node)[ln] (old node)[fn]
|
|
*/
|
|
if (plen > bit) {
|
|
in = node_alloc(net);
|
|
ln = node_alloc(net);
|
|
|
|
if (!in || !ln) {
|
|
if (in)
|
|
node_free_immediate(net, in);
|
|
if (ln)
|
|
node_free_immediate(net, ln);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
|
|
/*
|
|
* new intermediate node.
|
|
* RTN_RTINFO will
|
|
* be off since that an address that chooses one of
|
|
* the branches would not match less specific routes
|
|
* in the other branch
|
|
*/
|
|
|
|
in->fn_bit = bit;
|
|
|
|
RCU_INIT_POINTER(in->parent, pn);
|
|
in->leaf = fn->leaf;
|
|
atomic_inc(&rcu_dereference_protected(in->leaf,
|
|
lockdep_is_held(&table->tb6_lock))->rt6i_ref);
|
|
|
|
/* update parent pointer */
|
|
if (dir)
|
|
rcu_assign_pointer(pn->right, in);
|
|
else
|
|
rcu_assign_pointer(pn->left, in);
|
|
|
|
ln->fn_bit = plen;
|
|
|
|
RCU_INIT_POINTER(ln->parent, in);
|
|
rcu_assign_pointer(fn->parent, in);
|
|
|
|
if (addr_bit_set(addr, bit)) {
|
|
rcu_assign_pointer(in->right, ln);
|
|
rcu_assign_pointer(in->left, fn);
|
|
} else {
|
|
rcu_assign_pointer(in->left, ln);
|
|
rcu_assign_pointer(in->right, fn);
|
|
}
|
|
} else { /* plen <= bit */
|
|
|
|
/*
|
|
* (new leaf node)[ln]
|
|
* / \
|
|
* (old node)[fn] NULL
|
|
*/
|
|
|
|
ln = node_alloc(net);
|
|
|
|
if (!ln)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
ln->fn_bit = plen;
|
|
|
|
RCU_INIT_POINTER(ln->parent, pn);
|
|
|
|
if (addr_bit_set(&key->addr, plen))
|
|
RCU_INIT_POINTER(ln->right, fn);
|
|
else
|
|
RCU_INIT_POINTER(ln->left, fn);
|
|
|
|
rcu_assign_pointer(fn->parent, ln);
|
|
|
|
if (dir)
|
|
rcu_assign_pointer(pn->right, ln);
|
|
else
|
|
rcu_assign_pointer(pn->left, ln);
|
|
}
|
|
return ln;
|
|
}
|
|
|
|
static void fib6_copy_metrics(u32 *mp, const struct mx6_config *mxc)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < RTAX_MAX; i++) {
|
|
if (test_bit(i, mxc->mx_valid))
|
|
mp[i] = mxc->mx[i];
|
|
}
|
|
}
|
|
|
|
static int fib6_commit_metrics(struct dst_entry *dst, struct mx6_config *mxc)
|
|
{
|
|
if (!mxc->mx)
|
|
return 0;
|
|
|
|
if (dst->flags & DST_HOST) {
|
|
u32 *mp = dst_metrics_write_ptr(dst);
|
|
|
|
if (unlikely(!mp))
|
|
return -ENOMEM;
|
|
|
|
fib6_copy_metrics(mp, mxc);
|
|
} else {
|
|
dst_init_metrics(dst, mxc->mx, false);
|
|
|
|
/* We've stolen mx now. */
|
|
mxc->mx = NULL;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void fib6_purge_rt(struct rt6_info *rt, struct fib6_node *fn,
|
|
struct net *net)
|
|
{
|
|
struct fib6_table *table = rt->rt6i_table;
|
|
|
|
if (atomic_read(&rt->rt6i_ref) != 1) {
|
|
/* This route is used as dummy address holder in some split
|
|
* nodes. It is not leaked, but it still holds other resources,
|
|
* which must be released in time. So, scan ascendant nodes
|
|
* and replace dummy references to this route with references
|
|
* to still alive ones.
|
|
*/
|
|
while (fn) {
|
|
struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct rt6_info *new_leaf;
|
|
if (!(fn->fn_flags & RTN_RTINFO) && leaf == rt) {
|
|
new_leaf = fib6_find_prefix(net, table, fn);
|
|
atomic_inc(&new_leaf->rt6i_ref);
|
|
rcu_assign_pointer(fn->leaf, new_leaf);
|
|
rt6_release(rt);
|
|
}
|
|
fn = rcu_dereference_protected(fn->parent,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Insert routing information in a node.
|
|
*/
|
|
|
|
static int fib6_add_rt2node(struct fib6_node *fn, struct rt6_info *rt,
|
|
struct nl_info *info, struct mx6_config *mxc,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct rt6_info *leaf = rcu_dereference_protected(fn->leaf,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
struct rt6_info *iter = NULL;
|
|
struct rt6_info __rcu **ins;
|
|
struct rt6_info __rcu **fallback_ins = NULL;
|
|
int replace = (info->nlh &&
|
|
(info->nlh->nlmsg_flags & NLM_F_REPLACE));
|
|
int add = (!info->nlh ||
|
|
(info->nlh->nlmsg_flags & NLM_F_CREATE));
|
|
int found = 0;
|
|
bool rt_can_ecmp = rt6_qualify_for_ecmp(rt);
|
|
u16 nlflags = NLM_F_EXCL;
|
|
int err;
|
|
|
|
if (info->nlh && (info->nlh->nlmsg_flags & NLM_F_APPEND))
|
|
nlflags |= NLM_F_APPEND;
|
|
|
|
ins = &fn->leaf;
|
|
|
|
for (iter = leaf; iter;
|
|
iter = rcu_dereference_protected(iter->rt6_next,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock))) {
|
|
/*
|
|
* Search for duplicates
|
|
*/
|
|
|
|
if (iter->rt6i_metric == rt->rt6i_metric) {
|
|
/*
|
|
* Same priority level
|
|
*/
|
|
if (info->nlh &&
|
|
(info->nlh->nlmsg_flags & NLM_F_EXCL))
|
|
return -EEXIST;
|
|
|
|
nlflags &= ~NLM_F_EXCL;
|
|
if (replace) {
|
|
if (rt_can_ecmp == rt6_qualify_for_ecmp(iter)) {
|
|
found++;
|
|
break;
|
|
}
|
|
if (rt_can_ecmp)
|
|
fallback_ins = fallback_ins ?: ins;
|
|
goto next_iter;
|
|
}
|
|
|
|
if (rt6_duplicate_nexthop(iter, rt)) {
|
|
if (rt->rt6i_nsiblings)
|
|
rt->rt6i_nsiblings = 0;
|
|
if (!(iter->rt6i_flags & RTF_EXPIRES))
|
|
return -EEXIST;
|
|
if (!(rt->rt6i_flags & RTF_EXPIRES))
|
|
rt6_clean_expires(iter);
|
|
else
|
|
rt6_set_expires(iter, rt->dst.expires);
|
|
iter->rt6i_pmtu = rt->rt6i_pmtu;
|
|
return -EEXIST;
|
|
}
|
|
/* If we have the same destination and the same metric,
|
|
* but not the same gateway, then the route we try to
|
|
* add is sibling to this route, increment our counter
|
|
* of siblings, and later we will add our route to the
|
|
* list.
|
|
* Only static routes (which don't have flag
|
|
* RTF_EXPIRES) are used for ECMPv6.
|
|
*
|
|
* To avoid long list, we only had siblings if the
|
|
* route have a gateway.
|
|
*/
|
|
if (rt_can_ecmp &&
|
|
rt6_qualify_for_ecmp(iter))
|
|
rt->rt6i_nsiblings++;
|
|
}
|
|
|
|
if (iter->rt6i_metric > rt->rt6i_metric)
|
|
break;
|
|
|
|
next_iter:
|
|
ins = &iter->rt6_next;
|
|
}
|
|
|
|
if (fallback_ins && !found) {
|
|
/* No ECMP-able route found, replace first non-ECMP one */
|
|
ins = fallback_ins;
|
|
iter = rcu_dereference_protected(*ins,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
found++;
|
|
}
|
|
|
|
/* Reset round-robin state, if necessary */
|
|
if (ins == &fn->leaf)
|
|
fn->rr_ptr = NULL;
|
|
|
|
/* Link this route to others same route. */
|
|
if (rt->rt6i_nsiblings) {
|
|
unsigned int rt6i_nsiblings;
|
|
struct rt6_info *sibling, *temp_sibling;
|
|
|
|
/* Find the first route that have the same metric */
|
|
sibling = leaf;
|
|
while (sibling) {
|
|
if (sibling->rt6i_metric == rt->rt6i_metric &&
|
|
rt6_qualify_for_ecmp(sibling)) {
|
|
list_add_tail(&rt->rt6i_siblings,
|
|
&sibling->rt6i_siblings);
|
|
break;
|
|
}
|
|
sibling = rcu_dereference_protected(sibling->rt6_next,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
}
|
|
/* For each sibling in the list, increment the counter of
|
|
* siblings. BUG() if counters does not match, list of siblings
|
|
* is broken!
|
|
*/
|
|
rt6i_nsiblings = 0;
|
|
list_for_each_entry_safe(sibling, temp_sibling,
|
|
&rt->rt6i_siblings, rt6i_siblings) {
|
|
sibling->rt6i_nsiblings++;
|
|
BUG_ON(sibling->rt6i_nsiblings != rt->rt6i_nsiblings);
|
|
rt6i_nsiblings++;
|
|
}
|
|
BUG_ON(rt6i_nsiblings != rt->rt6i_nsiblings);
|
|
rt6_multipath_rebalance(temp_sibling);
|
|
}
|
|
|
|
/*
|
|
* insert node
|
|
*/
|
|
if (!replace) {
|
|
if (!add)
|
|
pr_warn("NLM_F_CREATE should be set when creating new route\n");
|
|
|
|
add:
|
|
nlflags |= NLM_F_CREATE;
|
|
err = fib6_commit_metrics(&rt->dst, mxc);
|
|
if (err)
|
|
return err;
|
|
|
|
err = call_fib6_entry_notifiers(info->nl_net,
|
|
FIB_EVENT_ENTRY_ADD,
|
|
rt, extack);
|
|
if (err)
|
|
return err;
|
|
|
|
rcu_assign_pointer(rt->rt6_next, iter);
|
|
atomic_inc(&rt->rt6i_ref);
|
|
rcu_assign_pointer(rt->rt6i_node, fn);
|
|
rcu_assign_pointer(*ins, rt);
|
|
if (!info->skip_notify)
|
|
inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
|
|
info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
|
|
|
|
if (!(fn->fn_flags & RTN_RTINFO)) {
|
|
info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
|
|
fn->fn_flags |= RTN_RTINFO;
|
|
}
|
|
|
|
} else {
|
|
int nsiblings;
|
|
|
|
if (!found) {
|
|
if (add)
|
|
goto add;
|
|
pr_warn("NLM_F_REPLACE set, but no existing node found!\n");
|
|
return -ENOENT;
|
|
}
|
|
|
|
err = fib6_commit_metrics(&rt->dst, mxc);
|
|
if (err)
|
|
return err;
|
|
|
|
err = call_fib6_entry_notifiers(info->nl_net,
|
|
FIB_EVENT_ENTRY_REPLACE,
|
|
rt, extack);
|
|
if (err)
|
|
return err;
|
|
|
|
atomic_inc(&rt->rt6i_ref);
|
|
rcu_assign_pointer(rt->rt6i_node, fn);
|
|
rt->rt6_next = iter->rt6_next;
|
|
rcu_assign_pointer(*ins, rt);
|
|
if (!info->skip_notify)
|
|
inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE);
|
|
if (!(fn->fn_flags & RTN_RTINFO)) {
|
|
info->nl_net->ipv6.rt6_stats->fib_route_nodes++;
|
|
fn->fn_flags |= RTN_RTINFO;
|
|
}
|
|
nsiblings = iter->rt6i_nsiblings;
|
|
iter->rt6i_node = NULL;
|
|
fib6_purge_rt(iter, fn, info->nl_net);
|
|
if (rcu_access_pointer(fn->rr_ptr) == iter)
|
|
fn->rr_ptr = NULL;
|
|
rt6_release(iter);
|
|
|
|
if (nsiblings) {
|
|
/* Replacing an ECMP route, remove all siblings */
|
|
ins = &rt->rt6_next;
|
|
iter = rcu_dereference_protected(*ins,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
while (iter) {
|
|
if (iter->rt6i_metric > rt->rt6i_metric)
|
|
break;
|
|
if (rt6_qualify_for_ecmp(iter)) {
|
|
*ins = iter->rt6_next;
|
|
iter->rt6i_node = NULL;
|
|
fib6_purge_rt(iter, fn, info->nl_net);
|
|
if (rcu_access_pointer(fn->rr_ptr) == iter)
|
|
fn->rr_ptr = NULL;
|
|
rt6_release(iter);
|
|
nsiblings--;
|
|
info->nl_net->ipv6.rt6_stats->fib_rt_entries--;
|
|
} else {
|
|
ins = &iter->rt6_next;
|
|
}
|
|
iter = rcu_dereference_protected(*ins,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
}
|
|
WARN_ON(nsiblings != 0);
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void fib6_start_gc(struct net *net, struct rt6_info *rt)
|
|
{
|
|
if (!timer_pending(&net->ipv6.ip6_fib_timer) &&
|
|
(rt->rt6i_flags & (RTF_EXPIRES | RTF_CACHE)))
|
|
mod_timer(&net->ipv6.ip6_fib_timer,
|
|
jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
|
|
}
|
|
|
|
void fib6_force_start_gc(struct net *net)
|
|
{
|
|
if (!timer_pending(&net->ipv6.ip6_fib_timer))
|
|
mod_timer(&net->ipv6.ip6_fib_timer,
|
|
jiffies + net->ipv6.sysctl.ip6_rt_gc_interval);
|
|
}
|
|
|
|
static void __fib6_update_sernum_upto_root(struct rt6_info *rt,
|
|
int sernum)
|
|
{
|
|
struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
|
|
/* paired with smp_rmb() in rt6_get_cookie_safe() */
|
|
smp_wmb();
|
|
while (fn) {
|
|
fn->fn_sernum = sernum;
|
|
fn = rcu_dereference_protected(fn->parent,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
}
|
|
}
|
|
|
|
void fib6_update_sernum_upto_root(struct net *net, struct rt6_info *rt)
|
|
{
|
|
__fib6_update_sernum_upto_root(rt, fib6_new_sernum(net));
|
|
}
|
|
|
|
/*
|
|
* Add routing information to the routing tree.
|
|
* <destination addr>/<source addr>
|
|
* with source addr info in sub-trees
|
|
* Need to own table->tb6_lock
|
|
*/
|
|
|
|
int fib6_add(struct fib6_node *root, struct rt6_info *rt,
|
|
struct nl_info *info, struct mx6_config *mxc,
|
|
struct netlink_ext_ack *extack)
|
|
{
|
|
struct fib6_table *table = rt->rt6i_table;
|
|
struct fib6_node *fn, *pn = NULL;
|
|
int err = -ENOMEM;
|
|
int allow_create = 1;
|
|
int replace_required = 0;
|
|
int sernum = fib6_new_sernum(info->nl_net);
|
|
|
|
if (WARN_ON_ONCE(!atomic_read(&rt->dst.__refcnt)))
|
|
return -EINVAL;
|
|
if (WARN_ON_ONCE(rt->rt6i_flags & RTF_CACHE))
|
|
return -EINVAL;
|
|
|
|
if (info->nlh) {
|
|
if (!(info->nlh->nlmsg_flags & NLM_F_CREATE))
|
|
allow_create = 0;
|
|
if (info->nlh->nlmsg_flags & NLM_F_REPLACE)
|
|
replace_required = 1;
|
|
}
|
|
if (!allow_create && !replace_required)
|
|
pr_warn("RTM_NEWROUTE with no NLM_F_CREATE or NLM_F_REPLACE\n");
|
|
|
|
fn = fib6_add_1(info->nl_net, table, root,
|
|
&rt->rt6i_dst.addr, rt->rt6i_dst.plen,
|
|
offsetof(struct rt6_info, rt6i_dst), allow_create,
|
|
replace_required, extack);
|
|
if (IS_ERR(fn)) {
|
|
err = PTR_ERR(fn);
|
|
fn = NULL;
|
|
goto out;
|
|
}
|
|
|
|
pn = fn;
|
|
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
if (rt->rt6i_src.plen) {
|
|
struct fib6_node *sn;
|
|
|
|
if (!rcu_access_pointer(fn->subtree)) {
|
|
struct fib6_node *sfn;
|
|
|
|
/*
|
|
* Create subtree.
|
|
*
|
|
* fn[main tree]
|
|
* |
|
|
* sfn[subtree root]
|
|
* \
|
|
* sn[new leaf node]
|
|
*/
|
|
|
|
/* Create subtree root node */
|
|
sfn = node_alloc(info->nl_net);
|
|
if (!sfn)
|
|
goto failure;
|
|
|
|
atomic_inc(&info->nl_net->ipv6.ip6_null_entry->rt6i_ref);
|
|
rcu_assign_pointer(sfn->leaf,
|
|
info->nl_net->ipv6.ip6_null_entry);
|
|
sfn->fn_flags = RTN_ROOT;
|
|
|
|
/* Now add the first leaf node to new subtree */
|
|
|
|
sn = fib6_add_1(info->nl_net, table, sfn,
|
|
&rt->rt6i_src.addr, rt->rt6i_src.plen,
|
|
offsetof(struct rt6_info, rt6i_src),
|
|
allow_create, replace_required, extack);
|
|
|
|
if (IS_ERR(sn)) {
|
|
/* If it is failed, discard just allocated
|
|
root, and then (in failure) stale node
|
|
in main tree.
|
|
*/
|
|
node_free_immediate(info->nl_net, sfn);
|
|
err = PTR_ERR(sn);
|
|
goto failure;
|
|
}
|
|
|
|
/* Now link new subtree to main tree */
|
|
rcu_assign_pointer(sfn->parent, fn);
|
|
rcu_assign_pointer(fn->subtree, sfn);
|
|
} else {
|
|
sn = fib6_add_1(info->nl_net, table, FIB6_SUBTREE(fn),
|
|
&rt->rt6i_src.addr, rt->rt6i_src.plen,
|
|
offsetof(struct rt6_info, rt6i_src),
|
|
allow_create, replace_required, extack);
|
|
|
|
if (IS_ERR(sn)) {
|
|
err = PTR_ERR(sn);
|
|
goto failure;
|
|
}
|
|
}
|
|
|
|
if (!rcu_access_pointer(fn->leaf)) {
|
|
if (fn->fn_flags & RTN_TL_ROOT) {
|
|
/* put back null_entry for root node */
|
|
rcu_assign_pointer(fn->leaf,
|
|
info->nl_net->ipv6.ip6_null_entry);
|
|
} else {
|
|
atomic_inc(&rt->rt6i_ref);
|
|
rcu_assign_pointer(fn->leaf, rt);
|
|
}
|
|
}
|
|
fn = sn;
|
|
}
|
|
#endif
|
|
|
|
err = fib6_add_rt2node(fn, rt, info, mxc, extack);
|
|
if (!err) {
|
|
__fib6_update_sernum_upto_root(rt, sernum);
|
|
fib6_start_gc(info->nl_net, rt);
|
|
}
|
|
|
|
out:
|
|
if (err) {
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
/*
|
|
* If fib6_add_1 has cleared the old leaf pointer in the
|
|
* super-tree leaf node we have to find a new one for it.
|
|
*/
|
|
if (pn != fn) {
|
|
struct rt6_info *pn_leaf =
|
|
rcu_dereference_protected(pn->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
if (pn_leaf == rt) {
|
|
pn_leaf = NULL;
|
|
RCU_INIT_POINTER(pn->leaf, NULL);
|
|
atomic_dec(&rt->rt6i_ref);
|
|
}
|
|
if (!pn_leaf && !(pn->fn_flags & RTN_RTINFO)) {
|
|
pn_leaf = fib6_find_prefix(info->nl_net, table,
|
|
pn);
|
|
#if RT6_DEBUG >= 2
|
|
if (!pn_leaf) {
|
|
WARN_ON(!pn_leaf);
|
|
pn_leaf =
|
|
info->nl_net->ipv6.ip6_null_entry;
|
|
}
|
|
#endif
|
|
atomic_inc(&pn_leaf->rt6i_ref);
|
|
rcu_assign_pointer(pn->leaf, pn_leaf);
|
|
}
|
|
}
|
|
#endif
|
|
goto failure;
|
|
}
|
|
return err;
|
|
|
|
failure:
|
|
/* fn->leaf could be NULL and fib6_repair_tree() needs to be called if:
|
|
* 1. fn is an intermediate node and we failed to add the new
|
|
* route to it in both subtree creation failure and fib6_add_rt2node()
|
|
* failure case.
|
|
* 2. fn is the root node in the table and we fail to add the first
|
|
* default route to it.
|
|
*/
|
|
if (fn &&
|
|
(!(fn->fn_flags & (RTN_RTINFO|RTN_ROOT)) ||
|
|
(fn->fn_flags & RTN_TL_ROOT &&
|
|
!rcu_access_pointer(fn->leaf))))
|
|
fib6_repair_tree(info->nl_net, table, fn);
|
|
/* Always release dst as dst->__refcnt is guaranteed
|
|
* to be taken before entering this function
|
|
*/
|
|
dst_release_immediate(&rt->dst);
|
|
return err;
|
|
}
|
|
|
|
/*
|
|
* Routing tree lookup
|
|
*
|
|
*/
|
|
|
|
struct lookup_args {
|
|
int offset; /* key offset on rt6_info */
|
|
const struct in6_addr *addr; /* search key */
|
|
};
|
|
|
|
static struct fib6_node *fib6_lookup_1(struct fib6_node *root,
|
|
struct lookup_args *args)
|
|
{
|
|
struct fib6_node *fn;
|
|
__be32 dir;
|
|
|
|
if (unlikely(args->offset == 0))
|
|
return NULL;
|
|
|
|
/*
|
|
* Descend on a tree
|
|
*/
|
|
|
|
fn = root;
|
|
|
|
for (;;) {
|
|
struct fib6_node *next;
|
|
|
|
dir = addr_bit_set(args->addr, fn->fn_bit);
|
|
|
|
next = dir ? rcu_dereference(fn->right) :
|
|
rcu_dereference(fn->left);
|
|
|
|
if (next) {
|
|
fn = next;
|
|
continue;
|
|
}
|
|
break;
|
|
}
|
|
|
|
while (fn) {
|
|
struct fib6_node *subtree = FIB6_SUBTREE(fn);
|
|
|
|
if (subtree || fn->fn_flags & RTN_RTINFO) {
|
|
struct rt6_info *leaf = rcu_dereference(fn->leaf);
|
|
struct rt6key *key;
|
|
|
|
if (!leaf)
|
|
goto backtrack;
|
|
|
|
key = (struct rt6key *) ((u8 *)leaf + args->offset);
|
|
|
|
if (ipv6_prefix_equal(&key->addr, args->addr, key->plen)) {
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
if (subtree) {
|
|
struct fib6_node *sfn;
|
|
sfn = fib6_lookup_1(subtree, args + 1);
|
|
if (!sfn)
|
|
goto backtrack;
|
|
fn = sfn;
|
|
}
|
|
#endif
|
|
if (fn->fn_flags & RTN_RTINFO)
|
|
return fn;
|
|
}
|
|
}
|
|
backtrack:
|
|
if (fn->fn_flags & RTN_ROOT)
|
|
break;
|
|
|
|
fn = rcu_dereference(fn->parent);
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
/* called with rcu_read_lock() held
|
|
*/
|
|
struct fib6_node *fib6_lookup(struct fib6_node *root, const struct in6_addr *daddr,
|
|
const struct in6_addr *saddr)
|
|
{
|
|
struct fib6_node *fn;
|
|
struct lookup_args args[] = {
|
|
{
|
|
.offset = offsetof(struct rt6_info, rt6i_dst),
|
|
.addr = daddr,
|
|
},
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
{
|
|
.offset = offsetof(struct rt6_info, rt6i_src),
|
|
.addr = saddr,
|
|
},
|
|
#endif
|
|
{
|
|
.offset = 0, /* sentinel */
|
|
}
|
|
};
|
|
|
|
fn = fib6_lookup_1(root, daddr ? args : args + 1);
|
|
if (!fn || fn->fn_flags & RTN_TL_ROOT)
|
|
fn = root;
|
|
|
|
return fn;
|
|
}
|
|
|
|
/*
|
|
* Get node with specified destination prefix (and source prefix,
|
|
* if subtrees are used)
|
|
* exact_match == true means we try to find fn with exact match of
|
|
* the passed in prefix addr
|
|
* exact_match == false means we try to find fn with longest prefix
|
|
* match of the passed in prefix addr. This is useful for finding fn
|
|
* for cached route as it will be stored in the exception table under
|
|
* the node with longest prefix length.
|
|
*/
|
|
|
|
|
|
static struct fib6_node *fib6_locate_1(struct fib6_node *root,
|
|
const struct in6_addr *addr,
|
|
int plen, int offset,
|
|
bool exact_match)
|
|
{
|
|
struct fib6_node *fn, *prev = NULL;
|
|
|
|
for (fn = root; fn ; ) {
|
|
struct rt6_info *leaf = rcu_dereference(fn->leaf);
|
|
struct rt6key *key;
|
|
|
|
/* This node is being deleted */
|
|
if (!leaf) {
|
|
if (plen <= fn->fn_bit)
|
|
goto out;
|
|
else
|
|
goto next;
|
|
}
|
|
|
|
key = (struct rt6key *)((u8 *)leaf + offset);
|
|
|
|
/*
|
|
* Prefix match
|
|
*/
|
|
if (plen < fn->fn_bit ||
|
|
!ipv6_prefix_equal(&key->addr, addr, fn->fn_bit))
|
|
goto out;
|
|
|
|
if (plen == fn->fn_bit)
|
|
return fn;
|
|
|
|
prev = fn;
|
|
|
|
next:
|
|
/*
|
|
* We have more bits to go
|
|
*/
|
|
if (addr_bit_set(addr, fn->fn_bit))
|
|
fn = rcu_dereference(fn->right);
|
|
else
|
|
fn = rcu_dereference(fn->left);
|
|
}
|
|
out:
|
|
if (exact_match)
|
|
return NULL;
|
|
else
|
|
return prev;
|
|
}
|
|
|
|
struct fib6_node *fib6_locate(struct fib6_node *root,
|
|
const struct in6_addr *daddr, int dst_len,
|
|
const struct in6_addr *saddr, int src_len,
|
|
bool exact_match)
|
|
{
|
|
struct fib6_node *fn;
|
|
|
|
fn = fib6_locate_1(root, daddr, dst_len,
|
|
offsetof(struct rt6_info, rt6i_dst),
|
|
exact_match);
|
|
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
if (src_len) {
|
|
WARN_ON(saddr == NULL);
|
|
if (fn) {
|
|
struct fib6_node *subtree = FIB6_SUBTREE(fn);
|
|
|
|
if (subtree) {
|
|
fn = fib6_locate_1(subtree, saddr, src_len,
|
|
offsetof(struct rt6_info, rt6i_src),
|
|
exact_match);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
if (fn && fn->fn_flags & RTN_RTINFO)
|
|
return fn;
|
|
|
|
return NULL;
|
|
}
|
|
|
|
|
|
/*
|
|
* Deletion
|
|
*
|
|
*/
|
|
|
|
static struct rt6_info *fib6_find_prefix(struct net *net,
|
|
struct fib6_table *table,
|
|
struct fib6_node *fn)
|
|
{
|
|
struct fib6_node *child_left, *child_right;
|
|
|
|
if (fn->fn_flags & RTN_ROOT)
|
|
return net->ipv6.ip6_null_entry;
|
|
|
|
while (fn) {
|
|
child_left = rcu_dereference_protected(fn->left,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
child_right = rcu_dereference_protected(fn->right,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
if (child_left)
|
|
return rcu_dereference_protected(child_left->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
if (child_right)
|
|
return rcu_dereference_protected(child_right->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
|
|
fn = FIB6_SUBTREE(fn);
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
/*
|
|
* Called to trim the tree of intermediate nodes when possible. "fn"
|
|
* is the node we want to try and remove.
|
|
* Need to own table->tb6_lock
|
|
*/
|
|
|
|
static struct fib6_node *fib6_repair_tree(struct net *net,
|
|
struct fib6_table *table,
|
|
struct fib6_node *fn)
|
|
{
|
|
int children;
|
|
int nstate;
|
|
struct fib6_node *child;
|
|
struct fib6_walker *w;
|
|
int iter = 0;
|
|
|
|
/* Set fn->leaf to null_entry for root node. */
|
|
if (fn->fn_flags & RTN_TL_ROOT) {
|
|
rcu_assign_pointer(fn->leaf, net->ipv6.ip6_null_entry);
|
|
return fn;
|
|
}
|
|
|
|
for (;;) {
|
|
struct fib6_node *fn_r = rcu_dereference_protected(fn->right,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct fib6_node *fn_l = rcu_dereference_protected(fn->left,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct fib6_node *pn = rcu_dereference_protected(fn->parent,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct fib6_node *pn_r = rcu_dereference_protected(pn->right,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct fib6_node *pn_l = rcu_dereference_protected(pn->left,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct rt6_info *fn_leaf = rcu_dereference_protected(fn->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct rt6_info *pn_leaf = rcu_dereference_protected(pn->leaf,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct rt6_info *new_fn_leaf;
|
|
|
|
RT6_TRACE("fixing tree: plen=%d iter=%d\n", fn->fn_bit, iter);
|
|
iter++;
|
|
|
|
WARN_ON(fn->fn_flags & RTN_RTINFO);
|
|
WARN_ON(fn->fn_flags & RTN_TL_ROOT);
|
|
WARN_ON(fn_leaf);
|
|
|
|
children = 0;
|
|
child = NULL;
|
|
if (fn_r)
|
|
child = fn_r, children |= 1;
|
|
if (fn_l)
|
|
child = fn_l, children |= 2;
|
|
|
|
if (children == 3 || FIB6_SUBTREE(fn)
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
/* Subtree root (i.e. fn) may have one child */
|
|
|| (children && fn->fn_flags & RTN_ROOT)
|
|
#endif
|
|
) {
|
|
new_fn_leaf = fib6_find_prefix(net, table, fn);
|
|
#if RT6_DEBUG >= 2
|
|
if (!new_fn_leaf) {
|
|
WARN_ON(!new_fn_leaf);
|
|
new_fn_leaf = net->ipv6.ip6_null_entry;
|
|
}
|
|
#endif
|
|
atomic_inc(&new_fn_leaf->rt6i_ref);
|
|
rcu_assign_pointer(fn->leaf, new_fn_leaf);
|
|
return pn;
|
|
}
|
|
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
if (FIB6_SUBTREE(pn) == fn) {
|
|
WARN_ON(!(fn->fn_flags & RTN_ROOT));
|
|
RCU_INIT_POINTER(pn->subtree, NULL);
|
|
nstate = FWS_L;
|
|
} else {
|
|
WARN_ON(fn->fn_flags & RTN_ROOT);
|
|
#endif
|
|
if (pn_r == fn)
|
|
rcu_assign_pointer(pn->right, child);
|
|
else if (pn_l == fn)
|
|
rcu_assign_pointer(pn->left, child);
|
|
#if RT6_DEBUG >= 2
|
|
else
|
|
WARN_ON(1);
|
|
#endif
|
|
if (child)
|
|
rcu_assign_pointer(child->parent, pn);
|
|
nstate = FWS_R;
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
}
|
|
#endif
|
|
|
|
read_lock(&net->ipv6.fib6_walker_lock);
|
|
FOR_WALKERS(net, w) {
|
|
if (!child) {
|
|
if (w->node == fn) {
|
|
RT6_TRACE("W %p adjusted by delnode 1, s=%d/%d\n", w, w->state, nstate);
|
|
w->node = pn;
|
|
w->state = nstate;
|
|
}
|
|
} else {
|
|
if (w->node == fn) {
|
|
w->node = child;
|
|
if (children&2) {
|
|
RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
|
|
w->state = w->state >= FWS_R ? FWS_U : FWS_INIT;
|
|
} else {
|
|
RT6_TRACE("W %p adjusted by delnode 2, s=%d\n", w, w->state);
|
|
w->state = w->state >= FWS_C ? FWS_U : FWS_INIT;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
read_unlock(&net->ipv6.fib6_walker_lock);
|
|
|
|
node_free(net, fn);
|
|
if (pn->fn_flags & RTN_RTINFO || FIB6_SUBTREE(pn))
|
|
return pn;
|
|
|
|
RCU_INIT_POINTER(pn->leaf, NULL);
|
|
rt6_release(pn_leaf);
|
|
fn = pn;
|
|
}
|
|
}
|
|
|
|
static void fib6_del_route(struct fib6_table *table, struct fib6_node *fn,
|
|
struct rt6_info __rcu **rtp, struct nl_info *info)
|
|
{
|
|
struct fib6_walker *w;
|
|
struct rt6_info *rt = rcu_dereference_protected(*rtp,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
struct net *net = info->nl_net;
|
|
|
|
RT6_TRACE("fib6_del_route\n");
|
|
|
|
WARN_ON_ONCE(rt->rt6i_flags & RTF_CACHE);
|
|
|
|
/* Unlink it */
|
|
*rtp = rt->rt6_next;
|
|
rt->rt6i_node = NULL;
|
|
net->ipv6.rt6_stats->fib_rt_entries--;
|
|
net->ipv6.rt6_stats->fib_discarded_routes++;
|
|
|
|
/* Flush all cached dst in exception table */
|
|
rt6_flush_exceptions(rt);
|
|
|
|
/* Reset round-robin state, if necessary */
|
|
if (rcu_access_pointer(fn->rr_ptr) == rt)
|
|
fn->rr_ptr = NULL;
|
|
|
|
/* Remove this entry from other siblings */
|
|
if (rt->rt6i_nsiblings) {
|
|
struct rt6_info *sibling, *next_sibling;
|
|
|
|
list_for_each_entry_safe(sibling, next_sibling,
|
|
&rt->rt6i_siblings, rt6i_siblings)
|
|
sibling->rt6i_nsiblings--;
|
|
rt->rt6i_nsiblings = 0;
|
|
list_del_init(&rt->rt6i_siblings);
|
|
rt6_multipath_rebalance(next_sibling);
|
|
}
|
|
|
|
/* Adjust walkers */
|
|
read_lock(&net->ipv6.fib6_walker_lock);
|
|
FOR_WALKERS(net, w) {
|
|
if (w->state == FWS_C && w->leaf == rt) {
|
|
RT6_TRACE("walker %p adjusted by delroute\n", w);
|
|
w->leaf = rcu_dereference_protected(rt->rt6_next,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
if (!w->leaf)
|
|
w->state = FWS_U;
|
|
}
|
|
}
|
|
read_unlock(&net->ipv6.fib6_walker_lock);
|
|
|
|
/* If it was last route, call fib6_repair_tree() to:
|
|
* 1. For root node, put back null_entry as how the table was created.
|
|
* 2. For other nodes, expunge its radix tree node.
|
|
*/
|
|
if (!rcu_access_pointer(fn->leaf)) {
|
|
if (!(fn->fn_flags & RTN_TL_ROOT)) {
|
|
fn->fn_flags &= ~RTN_RTINFO;
|
|
net->ipv6.rt6_stats->fib_route_nodes--;
|
|
}
|
|
fn = fib6_repair_tree(net, table, fn);
|
|
}
|
|
|
|
fib6_purge_rt(rt, fn, net);
|
|
|
|
call_fib6_entry_notifiers(net, FIB_EVENT_ENTRY_DEL, rt, NULL);
|
|
if (!info->skip_notify)
|
|
inet6_rt_notify(RTM_DELROUTE, rt, info, 0);
|
|
rt6_release(rt);
|
|
}
|
|
|
|
/* Need to own table->tb6_lock */
|
|
int fib6_del(struct rt6_info *rt, struct nl_info *info)
|
|
{
|
|
struct fib6_node *fn = rcu_dereference_protected(rt->rt6i_node,
|
|
lockdep_is_held(&rt->rt6i_table->tb6_lock));
|
|
struct fib6_table *table = rt->rt6i_table;
|
|
struct net *net = info->nl_net;
|
|
struct rt6_info __rcu **rtp;
|
|
struct rt6_info __rcu **rtp_next;
|
|
|
|
#if RT6_DEBUG >= 2
|
|
if (rt->dst.obsolete > 0) {
|
|
WARN_ON(fn);
|
|
return -ENOENT;
|
|
}
|
|
#endif
|
|
if (!fn || rt == net->ipv6.ip6_null_entry)
|
|
return -ENOENT;
|
|
|
|
WARN_ON(!(fn->fn_flags & RTN_RTINFO));
|
|
|
|
/* remove cached dst from exception table */
|
|
if (rt->rt6i_flags & RTF_CACHE)
|
|
return rt6_remove_exception_rt(rt);
|
|
|
|
/*
|
|
* Walk the leaf entries looking for ourself
|
|
*/
|
|
|
|
for (rtp = &fn->leaf; *rtp; rtp = rtp_next) {
|
|
struct rt6_info *cur = rcu_dereference_protected(*rtp,
|
|
lockdep_is_held(&table->tb6_lock));
|
|
if (rt == cur) {
|
|
fib6_del_route(table, fn, rtp, info);
|
|
return 0;
|
|
}
|
|
rtp_next = &cur->rt6_next;
|
|
}
|
|
return -ENOENT;
|
|
}
|
|
|
|
/*
|
|
* Tree traversal function.
|
|
*
|
|
* Certainly, it is not interrupt safe.
|
|
* However, it is internally reenterable wrt itself and fib6_add/fib6_del.
|
|
* It means, that we can modify tree during walking
|
|
* and use this function for garbage collection, clone pruning,
|
|
* cleaning tree when a device goes down etc. etc.
|
|
*
|
|
* It guarantees that every node will be traversed,
|
|
* and that it will be traversed only once.
|
|
*
|
|
* Callback function w->func may return:
|
|
* 0 -> continue walking.
|
|
* positive value -> walking is suspended (used by tree dumps,
|
|
* and probably by gc, if it will be split to several slices)
|
|
* negative value -> terminate walking.
|
|
*
|
|
* The function itself returns:
|
|
* 0 -> walk is complete.
|
|
* >0 -> walk is incomplete (i.e. suspended)
|
|
* <0 -> walk is terminated by an error.
|
|
*
|
|
* This function is called with tb6_lock held.
|
|
*/
|
|
|
|
static int fib6_walk_continue(struct fib6_walker *w)
|
|
{
|
|
struct fib6_node *fn, *pn, *left, *right;
|
|
|
|
/* w->root should always be table->tb6_root */
|
|
WARN_ON_ONCE(!(w->root->fn_flags & RTN_TL_ROOT));
|
|
|
|
for (;;) {
|
|
fn = w->node;
|
|
if (!fn)
|
|
return 0;
|
|
|
|
switch (w->state) {
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
case FWS_S:
|
|
if (FIB6_SUBTREE(fn)) {
|
|
w->node = FIB6_SUBTREE(fn);
|
|
continue;
|
|
}
|
|
w->state = FWS_L;
|
|
#endif
|
|
/* fall through */
|
|
case FWS_L:
|
|
left = rcu_dereference_protected(fn->left, 1);
|
|
if (left) {
|
|
w->node = left;
|
|
w->state = FWS_INIT;
|
|
continue;
|
|
}
|
|
w->state = FWS_R;
|
|
/* fall through */
|
|
case FWS_R:
|
|
right = rcu_dereference_protected(fn->right, 1);
|
|
if (right) {
|
|
w->node = right;
|
|
w->state = FWS_INIT;
|
|
continue;
|
|
}
|
|
w->state = FWS_C;
|
|
w->leaf = rcu_dereference_protected(fn->leaf, 1);
|
|
/* fall through */
|
|
case FWS_C:
|
|
if (w->leaf && fn->fn_flags & RTN_RTINFO) {
|
|
int err;
|
|
|
|
if (w->skip) {
|
|
w->skip--;
|
|
goto skip;
|
|
}
|
|
|
|
err = w->func(w);
|
|
if (err)
|
|
return err;
|
|
|
|
w->count++;
|
|
continue;
|
|
}
|
|
skip:
|
|
w->state = FWS_U;
|
|
/* fall through */
|
|
case FWS_U:
|
|
if (fn == w->root)
|
|
return 0;
|
|
pn = rcu_dereference_protected(fn->parent, 1);
|
|
left = rcu_dereference_protected(pn->left, 1);
|
|
right = rcu_dereference_protected(pn->right, 1);
|
|
w->node = pn;
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
if (FIB6_SUBTREE(pn) == fn) {
|
|
WARN_ON(!(fn->fn_flags & RTN_ROOT));
|
|
w->state = FWS_L;
|
|
continue;
|
|
}
|
|
#endif
|
|
if (left == fn) {
|
|
w->state = FWS_R;
|
|
continue;
|
|
}
|
|
if (right == fn) {
|
|
w->state = FWS_C;
|
|
w->leaf = rcu_dereference_protected(w->node->leaf, 1);
|
|
continue;
|
|
}
|
|
#if RT6_DEBUG >= 2
|
|
WARN_ON(1);
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
static int fib6_walk(struct net *net, struct fib6_walker *w)
|
|
{
|
|
int res;
|
|
|
|
w->state = FWS_INIT;
|
|
w->node = w->root;
|
|
|
|
fib6_walker_link(net, w);
|
|
res = fib6_walk_continue(w);
|
|
if (res <= 0)
|
|
fib6_walker_unlink(net, w);
|
|
return res;
|
|
}
|
|
|
|
static int fib6_clean_node(struct fib6_walker *w)
|
|
{
|
|
int res;
|
|
struct rt6_info *rt;
|
|
struct fib6_cleaner *c = container_of(w, struct fib6_cleaner, w);
|
|
struct nl_info info = {
|
|
.nl_net = c->net,
|
|
};
|
|
|
|
if (c->sernum != FIB6_NO_SERNUM_CHANGE &&
|
|
w->node->fn_sernum != c->sernum)
|
|
w->node->fn_sernum = c->sernum;
|
|
|
|
if (!c->func) {
|
|
WARN_ON_ONCE(c->sernum == FIB6_NO_SERNUM_CHANGE);
|
|
w->leaf = NULL;
|
|
return 0;
|
|
}
|
|
|
|
for_each_fib6_walker_rt(w) {
|
|
res = c->func(rt, c->arg);
|
|
if (res == -1) {
|
|
w->leaf = rt;
|
|
res = fib6_del(rt, &info);
|
|
if (res) {
|
|
#if RT6_DEBUG >= 2
|
|
pr_debug("%s: del failed: rt=%p@%p err=%d\n",
|
|
__func__, rt,
|
|
rcu_access_pointer(rt->rt6i_node),
|
|
res);
|
|
#endif
|
|
continue;
|
|
}
|
|
return 0;
|
|
} else if (res == -2) {
|
|
if (WARN_ON(!rt->rt6i_nsiblings))
|
|
continue;
|
|
rt = list_last_entry(&rt->rt6i_siblings,
|
|
struct rt6_info, rt6i_siblings);
|
|
continue;
|
|
}
|
|
WARN_ON(res != 0);
|
|
}
|
|
w->leaf = rt;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Convenient frontend to tree walker.
|
|
*
|
|
* func is called on each route.
|
|
* It may return -2 -> skip multipath route.
|
|
* -1 -> delete this route.
|
|
* 0 -> continue walking
|
|
*/
|
|
|
|
static void fib6_clean_tree(struct net *net, struct fib6_node *root,
|
|
int (*func)(struct rt6_info *, void *arg),
|
|
int sernum, void *arg)
|
|
{
|
|
struct fib6_cleaner c;
|
|
|
|
c.w.root = root;
|
|
c.w.func = fib6_clean_node;
|
|
c.w.count = 0;
|
|
c.w.skip = 0;
|
|
c.func = func;
|
|
c.sernum = sernum;
|
|
c.arg = arg;
|
|
c.net = net;
|
|
|
|
fib6_walk(net, &c.w);
|
|
}
|
|
|
|
static void __fib6_clean_all(struct net *net,
|
|
int (*func)(struct rt6_info *, void *),
|
|
int sernum, void *arg)
|
|
{
|
|
struct fib6_table *table;
|
|
struct hlist_head *head;
|
|
unsigned int h;
|
|
|
|
rcu_read_lock();
|
|
for (h = 0; h < FIB6_TABLE_HASHSZ; h++) {
|
|
head = &net->ipv6.fib_table_hash[h];
|
|
hlist_for_each_entry_rcu(table, head, tb6_hlist) {
|
|
spin_lock_bh(&table->tb6_lock);
|
|
fib6_clean_tree(net, &table->tb6_root,
|
|
func, sernum, arg);
|
|
spin_unlock_bh(&table->tb6_lock);
|
|
}
|
|
}
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *),
|
|
void *arg)
|
|
{
|
|
__fib6_clean_all(net, func, FIB6_NO_SERNUM_CHANGE, arg);
|
|
}
|
|
|
|
static void fib6_flush_trees(struct net *net)
|
|
{
|
|
int new_sernum = fib6_new_sernum(net);
|
|
|
|
__fib6_clean_all(net, NULL, new_sernum, NULL);
|
|
}
|
|
|
|
/*
|
|
* Garbage collection
|
|
*/
|
|
|
|
static int fib6_age(struct rt6_info *rt, void *arg)
|
|
{
|
|
struct fib6_gc_args *gc_args = arg;
|
|
unsigned long now = jiffies;
|
|
|
|
/*
|
|
* check addrconf expiration here.
|
|
* Routes are expired even if they are in use.
|
|
*/
|
|
|
|
if (rt->rt6i_flags & RTF_EXPIRES && rt->dst.expires) {
|
|
if (time_after(now, rt->dst.expires)) {
|
|
RT6_TRACE("expiring %p\n", rt);
|
|
return -1;
|
|
}
|
|
gc_args->more++;
|
|
}
|
|
|
|
/* Also age clones in the exception table.
|
|
* Note, that clones are aged out
|
|
* only if they are not in use now.
|
|
*/
|
|
rt6_age_exceptions(rt, gc_args, now);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void fib6_run_gc(unsigned long expires, struct net *net, bool force)
|
|
{
|
|
struct fib6_gc_args gc_args;
|
|
unsigned long now;
|
|
|
|
if (force) {
|
|
spin_lock_bh(&net->ipv6.fib6_gc_lock);
|
|
} else if (!spin_trylock_bh(&net->ipv6.fib6_gc_lock)) {
|
|
mod_timer(&net->ipv6.ip6_fib_timer, jiffies + HZ);
|
|
return;
|
|
}
|
|
gc_args.timeout = expires ? (int)expires :
|
|
net->ipv6.sysctl.ip6_rt_gc_interval;
|
|
gc_args.more = 0;
|
|
|
|
fib6_clean_all(net, fib6_age, &gc_args);
|
|
now = jiffies;
|
|
net->ipv6.ip6_rt_last_gc = now;
|
|
|
|
if (gc_args.more)
|
|
mod_timer(&net->ipv6.ip6_fib_timer,
|
|
round_jiffies(now
|
|
+ net->ipv6.sysctl.ip6_rt_gc_interval));
|
|
else
|
|
del_timer(&net->ipv6.ip6_fib_timer);
|
|
spin_unlock_bh(&net->ipv6.fib6_gc_lock);
|
|
}
|
|
|
|
static void fib6_gc_timer_cb(struct timer_list *t)
|
|
{
|
|
struct net *arg = from_timer(arg, t, ipv6.ip6_fib_timer);
|
|
|
|
fib6_run_gc(0, arg, true);
|
|
}
|
|
|
|
static int __net_init fib6_net_init(struct net *net)
|
|
{
|
|
size_t size = sizeof(struct hlist_head) * FIB6_TABLE_HASHSZ;
|
|
int err;
|
|
|
|
err = fib6_notifier_init(net);
|
|
if (err)
|
|
return err;
|
|
|
|
spin_lock_init(&net->ipv6.fib6_gc_lock);
|
|
rwlock_init(&net->ipv6.fib6_walker_lock);
|
|
INIT_LIST_HEAD(&net->ipv6.fib6_walkers);
|
|
timer_setup(&net->ipv6.ip6_fib_timer, fib6_gc_timer_cb, 0);
|
|
|
|
net->ipv6.rt6_stats = kzalloc(sizeof(*net->ipv6.rt6_stats), GFP_KERNEL);
|
|
if (!net->ipv6.rt6_stats)
|
|
goto out_timer;
|
|
|
|
/* Avoid false sharing : Use at least a full cache line */
|
|
size = max_t(size_t, size, L1_CACHE_BYTES);
|
|
|
|
net->ipv6.fib_table_hash = kzalloc(size, GFP_KERNEL);
|
|
if (!net->ipv6.fib_table_hash)
|
|
goto out_rt6_stats;
|
|
|
|
net->ipv6.fib6_main_tbl = kzalloc(sizeof(*net->ipv6.fib6_main_tbl),
|
|
GFP_KERNEL);
|
|
if (!net->ipv6.fib6_main_tbl)
|
|
goto out_fib_table_hash;
|
|
|
|
net->ipv6.fib6_main_tbl->tb6_id = RT6_TABLE_MAIN;
|
|
rcu_assign_pointer(net->ipv6.fib6_main_tbl->tb6_root.leaf,
|
|
net->ipv6.ip6_null_entry);
|
|
net->ipv6.fib6_main_tbl->tb6_root.fn_flags =
|
|
RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
|
|
inet_peer_base_init(&net->ipv6.fib6_main_tbl->tb6_peers);
|
|
|
|
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
|
|
net->ipv6.fib6_local_tbl = kzalloc(sizeof(*net->ipv6.fib6_local_tbl),
|
|
GFP_KERNEL);
|
|
if (!net->ipv6.fib6_local_tbl)
|
|
goto out_fib6_main_tbl;
|
|
net->ipv6.fib6_local_tbl->tb6_id = RT6_TABLE_LOCAL;
|
|
rcu_assign_pointer(net->ipv6.fib6_local_tbl->tb6_root.leaf,
|
|
net->ipv6.ip6_null_entry);
|
|
net->ipv6.fib6_local_tbl->tb6_root.fn_flags =
|
|
RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO;
|
|
inet_peer_base_init(&net->ipv6.fib6_local_tbl->tb6_peers);
|
|
#endif
|
|
fib6_tables_init(net);
|
|
|
|
return 0;
|
|
|
|
#ifdef CONFIG_IPV6_MULTIPLE_TABLES
|
|
out_fib6_main_tbl:
|
|
kfree(net->ipv6.fib6_main_tbl);
|
|
#endif
|
|
out_fib_table_hash:
|
|
kfree(net->ipv6.fib_table_hash);
|
|
out_rt6_stats:
|
|
kfree(net->ipv6.rt6_stats);
|
|
out_timer:
|
|
fib6_notifier_exit(net);
|
|
return -ENOMEM;
|
|
}
|
|
|
|
static void fib6_net_exit(struct net *net)
|
|
{
|
|
unsigned int i;
|
|
|
|
del_timer_sync(&net->ipv6.ip6_fib_timer);
|
|
|
|
for (i = 0; i < FIB6_TABLE_HASHSZ; i++) {
|
|
struct hlist_head *head = &net->ipv6.fib_table_hash[i];
|
|
struct hlist_node *tmp;
|
|
struct fib6_table *tb;
|
|
|
|
hlist_for_each_entry_safe(tb, tmp, head, tb6_hlist) {
|
|
hlist_del(&tb->tb6_hlist);
|
|
fib6_free_table(tb);
|
|
}
|
|
}
|
|
|
|
kfree(net->ipv6.fib_table_hash);
|
|
kfree(net->ipv6.rt6_stats);
|
|
fib6_notifier_exit(net);
|
|
}
|
|
|
|
static struct pernet_operations fib6_net_ops = {
|
|
.init = fib6_net_init,
|
|
.exit = fib6_net_exit,
|
|
};
|
|
|
|
int __init fib6_init(void)
|
|
{
|
|
int ret = -ENOMEM;
|
|
|
|
fib6_node_kmem = kmem_cache_create("fib6_nodes",
|
|
sizeof(struct fib6_node),
|
|
0, SLAB_HWCACHE_ALIGN,
|
|
NULL);
|
|
if (!fib6_node_kmem)
|
|
goto out;
|
|
|
|
ret = register_pernet_subsys(&fib6_net_ops);
|
|
if (ret)
|
|
goto out_kmem_cache_create;
|
|
|
|
ret = rtnl_register_module(THIS_MODULE, PF_INET6, RTM_GETROUTE, NULL,
|
|
inet6_dump_fib, 0);
|
|
if (ret)
|
|
goto out_unregister_subsys;
|
|
|
|
__fib6_flush_trees = fib6_flush_trees;
|
|
out:
|
|
return ret;
|
|
|
|
out_unregister_subsys:
|
|
unregister_pernet_subsys(&fib6_net_ops);
|
|
out_kmem_cache_create:
|
|
kmem_cache_destroy(fib6_node_kmem);
|
|
goto out;
|
|
}
|
|
|
|
void fib6_gc_cleanup(void)
|
|
{
|
|
unregister_pernet_subsys(&fib6_net_ops);
|
|
kmem_cache_destroy(fib6_node_kmem);
|
|
}
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
|
|
struct ipv6_route_iter {
|
|
struct seq_net_private p;
|
|
struct fib6_walker w;
|
|
loff_t skip;
|
|
struct fib6_table *tbl;
|
|
int sernum;
|
|
};
|
|
|
|
static int ipv6_route_seq_show(struct seq_file *seq, void *v)
|
|
{
|
|
struct rt6_info *rt = v;
|
|
struct ipv6_route_iter *iter = seq->private;
|
|
|
|
seq_printf(seq, "%pi6 %02x ", &rt->rt6i_dst.addr, rt->rt6i_dst.plen);
|
|
|
|
#ifdef CONFIG_IPV6_SUBTREES
|
|
seq_printf(seq, "%pi6 %02x ", &rt->rt6i_src.addr, rt->rt6i_src.plen);
|
|
#else
|
|
seq_puts(seq, "00000000000000000000000000000000 00 ");
|
|
#endif
|
|
if (rt->rt6i_flags & RTF_GATEWAY)
|
|
seq_printf(seq, "%pi6", &rt->rt6i_gateway);
|
|
else
|
|
seq_puts(seq, "00000000000000000000000000000000");
|
|
|
|
seq_printf(seq, " %08x %08x %08x %08x %8s\n",
|
|
rt->rt6i_metric, atomic_read(&rt->dst.__refcnt),
|
|
rt->dst.__use, rt->rt6i_flags,
|
|
rt->dst.dev ? rt->dst.dev->name : "");
|
|
iter->w.leaf = NULL;
|
|
return 0;
|
|
}
|
|
|
|
static int ipv6_route_yield(struct fib6_walker *w)
|
|
{
|
|
struct ipv6_route_iter *iter = w->args;
|
|
|
|
if (!iter->skip)
|
|
return 1;
|
|
|
|
do {
|
|
iter->w.leaf = rcu_dereference_protected(
|
|
iter->w.leaf->rt6_next,
|
|
lockdep_is_held(&iter->tbl->tb6_lock));
|
|
iter->skip--;
|
|
if (!iter->skip && iter->w.leaf)
|
|
return 1;
|
|
} while (iter->w.leaf);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void ipv6_route_seq_setup_walk(struct ipv6_route_iter *iter,
|
|
struct net *net)
|
|
{
|
|
memset(&iter->w, 0, sizeof(iter->w));
|
|
iter->w.func = ipv6_route_yield;
|
|
iter->w.root = &iter->tbl->tb6_root;
|
|
iter->w.state = FWS_INIT;
|
|
iter->w.node = iter->w.root;
|
|
iter->w.args = iter;
|
|
iter->sernum = iter->w.root->fn_sernum;
|
|
INIT_LIST_HEAD(&iter->w.lh);
|
|
fib6_walker_link(net, &iter->w);
|
|
}
|
|
|
|
static struct fib6_table *ipv6_route_seq_next_table(struct fib6_table *tbl,
|
|
struct net *net)
|
|
{
|
|
unsigned int h;
|
|
struct hlist_node *node;
|
|
|
|
if (tbl) {
|
|
h = (tbl->tb6_id & (FIB6_TABLE_HASHSZ - 1)) + 1;
|
|
node = rcu_dereference_bh(hlist_next_rcu(&tbl->tb6_hlist));
|
|
} else {
|
|
h = 0;
|
|
node = NULL;
|
|
}
|
|
|
|
while (!node && h < FIB6_TABLE_HASHSZ) {
|
|
node = rcu_dereference_bh(
|
|
hlist_first_rcu(&net->ipv6.fib_table_hash[h++]));
|
|
}
|
|
return hlist_entry_safe(node, struct fib6_table, tb6_hlist);
|
|
}
|
|
|
|
static void ipv6_route_check_sernum(struct ipv6_route_iter *iter)
|
|
{
|
|
if (iter->sernum != iter->w.root->fn_sernum) {
|
|
iter->sernum = iter->w.root->fn_sernum;
|
|
iter->w.state = FWS_INIT;
|
|
iter->w.node = iter->w.root;
|
|
WARN_ON(iter->w.skip);
|
|
iter->w.skip = iter->w.count;
|
|
}
|
|
}
|
|
|
|
static void *ipv6_route_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
{
|
|
int r;
|
|
struct rt6_info *n;
|
|
struct net *net = seq_file_net(seq);
|
|
struct ipv6_route_iter *iter = seq->private;
|
|
|
|
if (!v)
|
|
goto iter_table;
|
|
|
|
n = rcu_dereference_bh(((struct rt6_info *)v)->rt6_next);
|
|
if (n) {
|
|
++*pos;
|
|
return n;
|
|
}
|
|
|
|
iter_table:
|
|
ipv6_route_check_sernum(iter);
|
|
spin_lock_bh(&iter->tbl->tb6_lock);
|
|
r = fib6_walk_continue(&iter->w);
|
|
spin_unlock_bh(&iter->tbl->tb6_lock);
|
|
if (r > 0) {
|
|
if (v)
|
|
++*pos;
|
|
return iter->w.leaf;
|
|
} else if (r < 0) {
|
|
fib6_walker_unlink(net, &iter->w);
|
|
return NULL;
|
|
}
|
|
fib6_walker_unlink(net, &iter->w);
|
|
|
|
iter->tbl = ipv6_route_seq_next_table(iter->tbl, net);
|
|
if (!iter->tbl)
|
|
return NULL;
|
|
|
|
ipv6_route_seq_setup_walk(iter, net);
|
|
goto iter_table;
|
|
}
|
|
|
|
static void *ipv6_route_seq_start(struct seq_file *seq, loff_t *pos)
|
|
__acquires(RCU_BH)
|
|
{
|
|
struct net *net = seq_file_net(seq);
|
|
struct ipv6_route_iter *iter = seq->private;
|
|
|
|
rcu_read_lock_bh();
|
|
iter->tbl = ipv6_route_seq_next_table(NULL, net);
|
|
iter->skip = *pos;
|
|
|
|
if (iter->tbl) {
|
|
ipv6_route_seq_setup_walk(iter, net);
|
|
return ipv6_route_seq_next(seq, NULL, pos);
|
|
} else {
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
static bool ipv6_route_iter_active(struct ipv6_route_iter *iter)
|
|
{
|
|
struct fib6_walker *w = &iter->w;
|
|
return w->node && !(w->state == FWS_U && w->node == w->root);
|
|
}
|
|
|
|
static void ipv6_route_seq_stop(struct seq_file *seq, void *v)
|
|
__releases(RCU_BH)
|
|
{
|
|
struct net *net = seq_file_net(seq);
|
|
struct ipv6_route_iter *iter = seq->private;
|
|
|
|
if (ipv6_route_iter_active(iter))
|
|
fib6_walker_unlink(net, &iter->w);
|
|
|
|
rcu_read_unlock_bh();
|
|
}
|
|
|
|
static const struct seq_operations ipv6_route_seq_ops = {
|
|
.start = ipv6_route_seq_start,
|
|
.next = ipv6_route_seq_next,
|
|
.stop = ipv6_route_seq_stop,
|
|
.show = ipv6_route_seq_show
|
|
};
|
|
|
|
int ipv6_route_open(struct inode *inode, struct file *file)
|
|
{
|
|
return seq_open_net(inode, file, &ipv6_route_seq_ops,
|
|
sizeof(struct ipv6_route_iter));
|
|
}
|
|
|
|
#endif /* CONFIG_PROC_FS */
|