| /* |
| * Linux INET6 implementation |
| * Forwarding Information Database |
| * |
| * Authors: |
| * Pedro Roque <roque@di.fc.ul.pt> |
| * |
| * 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. |
| * |
| * Changes: |
| * Yuji SEKIYA @USAGI: Support default route on router node; |
| * remove ip6_null_entry from the top of |
| * routing table. |
| * Ville Nuorvala: Fixed routing subtrees. |
| */ |
| |
| #define pr_fmt(fmt) "IPv6: " fmt |
| |
| #include <linux/errno.h> |
| #include <linux/types.h> |
| #include <linux/net.h> |
| #include <linux/route.h> |
| #include <linux/netdevice.h> |
| #include <linux/in6.h> |
| #include <linux/init.h> |
| #include <linux/list.h> |
| #include <linux/slab.h> |
| |
| #include <net/ip.h> |
| #include <net/ipv6.h> |
| #include <net/ndisc.h> |
| #include <net/addrconf.h> |
| #include <net/lwtunnel.h> |
| #include <net/fib_notifier.h> |
| |
| #include <net/ip6_fib.h> |
| #include <net/ip6_route.h> |
| |
| static struct kmem_cache *fib6_node_kmem __read_mostly; |
| |
| struct fib6_cleaner { |
| struct fib6_walker w; |
| struct net *net; |
| int (*func)(struct fib6_info *, void *arg); |
| int sernum; |
| void *arg; |
| bool skip_notify; |
| }; |
| |
| #ifdef CONFIG_IPV6_SUBTREES |
| #define FWS_INIT FWS_S |
| #else |
| #define FWS_INIT FWS_L |
| #endif |
| |
| static struct fib6_info *fib6_find_prefix(struct net *net, |
| struct fib6_table *table, |
| struct fib6_node *fn); |
| static struct fib6_node *fib6_repair_tree(struct net *net, |
| struct fib6_table *table, |
| struct fib6_node *fn); |
| static int fib6_walk(struct net *net, struct fib6_walker *w); |
| static int fib6_walk_continue(struct fib6_walker *w); |
| |
| /* |
| * A routing update causes an increase of the serial number on the |
| * affected subtree. This allows for cached routes to be asynchronously |
| * tested when modifications are made to the destination cache as a |
| * result of redirects, path MTU changes, etc. |
| */ |
| |
| static void fib6_gc_timer_cb(struct timer_list *t); |
| |
| #define FOR_WALKERS(net, w) \ |
| list_for_each_entry(w, &(net)->ipv6.fib6_walkers, lh) |
| |
| static void fib6_walker_link(struct net *net, struct fib6_walker *w) |
| { |
| write_lock_bh(&net->ipv6.fib6_walker_lock); |
| list_add(&w->lh, &net->ipv6.fib6_walkers); |
| write_unlock_bh(&net->ipv6.fib6_walker_lock); |
| } |
| |
| static void fib6_walker_unlink(struct net *net, struct fib6_walker *w) |
| { |
| write_lock_bh(&net->ipv6.fib6_walker_lock); |
| list_del(&w->lh); |
| write_unlock_bh(&net->ipv6.fib6_walker_lock); |
| } |
| |
| static int fib6_new_sernum(struct net *net) |
| { |
| int new, old; |
| |
| do { |
| old = atomic_read(&net->ipv6.fib6_sernum); |
| new = old < INT_MAX ? old + 1 : 1; |
| } while (atomic_cmpxchg(&net->ipv6.fib6_sernum, |
| old, new) != old); |
| return new; |
| } |
| |
| enum { |
| FIB6_NO_SERNUM_CHANGE = 0, |
| }; |
| |
| void fib6_update_sernum(struct net *net, struct fib6_info *f6i) |
| { |
| struct fib6_node *fn; |
| |
| fn = rcu_dereference_protected(f6i->fib6_node, |
| lockdep_is_held(&f6i->fib6_table->tb6_lock)); |
| if (fn) |
| fn->fn_sernum = fib6_new_sernum(net); |
| } |
| |
| /* |
| * Auxiliary address test functions for the radix tree. |
| * |
| * These assume a 32bit processor (although it will work on |
| * 64bit processors) |
| */ |
| |
| /* |
| * test bit |
| */ |
| #if defined(__LITTLE_ENDIAN) |
| # define BITOP_BE32_SWIZZLE (0x1F & ~7) |
| #else |
| # define BITOP_BE32_SWIZZLE 0 |
| #endif |
| |
| static __be32 addr_bit_set(const void *token, int fn_bit) |
| { |
| const __be32 *addr = token; |
| /* |
| * Here, |
| * 1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f) |
| * is optimized version of |
| * htonl(1 << ((~fn_bit)&0x1F)) |
| * See include/asm-generic/bitops/le.h. |
| */ |
| return (__force __be32)(1 << ((~fn_bit ^ BITOP_BE32_SWIZZLE) & 0x1f)) & |
| addr[fn_bit >> 5]; |
| } |
| |
| struct fib6_info *fib6_info_alloc(gfp_t gfp_flags) |
| { |
| struct fib6_info *f6i; |
| |
| f6i = kzalloc(sizeof(*f6i), gfp_flags); |
| if (!f6i) |
| return NULL; |
| |
| f6i->rt6i_pcpu = alloc_percpu_gfp(struct rt6_info *, gfp_flags); |
| if (!f6i->rt6i_pcpu) { |
| kfree(f6i); |
| return NULL; |
| } |
| |
| INIT_LIST_HEAD(&f6i->fib6_siblings); |
| refcount_set(&f6i->fib6_ref, 1); |
| |
| return f6i; |
| } |
| |
| void fib6_info_destroy_rcu(struct rcu_head *head) |
| { |
| struct fib6_info *f6i = container_of(head, struct fib6_info, rcu); |
| struct rt6_exception_bucket *bucket; |
| |
| WARN_ON(f6i->fib6_node); |
| |
| bucket = rcu_dereference_protected(f6i->rt6i_exception_bucket, 1); |
| kfree(bucket); |
| |
| if (f6i->rt6i_pcpu) { |
| int cpu; |
| |
| for_each_possible_cpu(cpu) { |
| struct rt6_info **ppcpu_rt; |
| struct rt6_info *pcpu_rt; |
| |
| ppcpu_rt = per_cpu_ptr(f6i->rt6i_pcpu, cpu); |
| pcpu_rt = *ppcpu_rt; |
| if (pcpu_rt) { |
| dst_dev_put(&pcpu_rt->dst); |
| dst_release(&pcpu_rt->dst); |
| *ppcpu_rt = NULL; |
| } |
| } |
| |
| free_percpu(f6i->rt6i_pcpu); |
| } |
| |
| fib6_nh_release(&f6i->fib6_nh); |
| |
| ip_fib_metrics_put(f6i->fib6_metrics); |
| |
| kfree(f6i); |
| } |
| EXPORT_SYMBOL_GPL(fib6_info_destroy_rcu); |
| |
| static struct fib6_node *node_alloc(struct net *net) |
| { |
| struct fib6_node *fn; |
| |
| fn = kmem_cache_zalloc(fib6_node_kmem, GFP_ATOMIC); |
| if (fn) |
| net->ipv6.rt6_stats->fib_nodes++; |
| |
| return fn; |
| } |
| |
| static void node_free_immediate(struct net *net, struct fib6_node *fn) |
| { |
| kmem_cache_free(fib6_node_kmem, fn); |
| net->ipv6.rt6_stats->fib_nodes--; |
| } |
| |
| static void node_free_rcu(struct rcu_head *head) |
| { |
| struct fib6_node *fn = container_of(head, struct fib6_node, rcu); |
| |
| kmem_cache_free(fib6_node_kmem, fn); |
| } |
| |
| static void node_free(struct net *net, struct fib6_node *fn) |
| { |
| call_rcu(&fn->rcu, node_free_rcu); |
| net->ipv6.rt6_stats->fib_nodes--; |
| } |
| |
| static void fib6_free_table(struct fib6_table *table) |
| { |
| inetpeer_invalidate_tree(&table->tb6_peers); |
| kfree(table); |
| } |
| |
| static void fib6_link_table(struct net *net, struct fib6_table *tb) |
| { |
| unsigned int h; |
| |
| /* |
| * Initialize table lock at a single place to give lockdep a key, |
| * tables aren't visible prior to being linked to the list. |
| */ |
| spin_lock_init(&tb->tb6_lock); |
| h = tb->tb6_id & (FIB6_TABLE_HASHSZ - 1); |
| |
| /* |
| * No protection necessary, this is the only list mutatation |
| * operation, tables never disappear once they exist. |
| */ |
| hlist_add_head_rcu(&tb->tb6_hlist, &net->ipv6.fib_table_hash[h]); |
| } |
| |
| #ifdef CONFIG_IPV6_MULTIPLE_TABLES |
| |
| static struct fib6_table *fib6_alloc_table(struct net *net, u32 id) |
| { |
| struct fib6_table *table; |
| |
| table = kzalloc(sizeof(*table), GFP_ATOMIC); |
| if (table) { |
| table->tb6_id = id; |
| rcu_assign_pointer(table->tb6_root.leaf, |
| net->ipv6.fib6_null_entry); |
| table->tb6_root.fn_flags = RTN_ROOT | RTN_TL_ROOT | RTN_RTINFO; |
| inet_peer_base_init(&table->tb6_peers); |
| } |
| |
| return table; |
| } |
| |
| struct fib6_table *fib6_new_table(struct net *net, u32 id) |
| { |
| struct fib6_table *tb; |
| |
| if (id == 0) |
| id = RT6_TABLE_MAIN; |
| tb = fib6_get_table(net, id); |
| if (tb) |
| return tb; |
| |
| tb = fib6_alloc_table(net, id); |
| if (tb) |
| fib6_link_table(net, tb); |
| |
| return tb; |
| } |
| EXPORT_SYMBOL_GPL(fib6_new_table); |
| |
| struct fib6_table *fib6_get_table(struct net *net, u32 id) |
| { |
| struct fib6_table *tb; |
| struct hlist_head *head; |
| unsigned int h; |
| |
| if (id == 0) |
| id = RT6_TABLE_MAIN; |
| h = id & (FIB6_TABLE_HASHSZ - 1); |
| rcu_read_lock(); |
| head = &net->ipv6.fib_table_hash[h]; |
| hlist_for_each_entry_rcu(tb, head, tb6_hlist) { |
| if (tb->tb6_id == id) { |
| rcu_read_unlock(); |
| return tb; |
| } |
| } |
| rcu_read_unlock(); |
| |
| return NULL; |
| } |
| EXPORT_SYMBOL_GPL(fib6_get_table); |
| |
| static void __net_init fib6_tables_init(struct net *net) |
| { |
| fib6_link_table(net, net->ipv6.fib6_main_tbl); |
| fib6_link_table(net, net->ipv6.fib6_local_tbl); |
| } |
| #else |
| |
| struct fib6_table *fib6_new_table(struct net *net, u32 id) |
| { |
| return fib6_get_table(net, id); |
| } |
| |
| struct fib6_table *fib6_get_table(struct net *net, u32 id) |
| { |
| return net->ipv6.fib6_main_tbl; |
| } |
| |
| struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, |
| const struct sk_buff *skb, |
| int flags, pol_lookup_t lookup) |
| { |
| struct rt6_info *rt; |
| |
| rt = lookup(net, net->ipv6.fib6_main_tbl, fl6, skb, flags); |
| if (rt->dst.error == -EAGAIN) { |
| ip6_rt_put(rt); |
| rt = net->ipv6.ip6_null_entry; |
| dst_hold(&rt->dst); |
| } |
| |
| return &rt->dst; |
| } |
| |
| /* called with rcu lock held; no reference taken on fib6_info */ |
| int fib6_lookup(struct net *net, int oif, struct flowi6 *fl6, |
| struct fib6_result *res, int flags) |
| { |
| return fib6_table_lookup(net, net->ipv6.fib6_main_tbl, oif, fl6, |
| res, flags); |
| } |
| |
| static void __net_init fib6_tables_init(struct net *net) |
| { |
| fib6_link_table(net, net->ipv6.fib6_main_tbl); |
| } |
| |
| #endif |
| |
| unsigned int fib6_tables_seq_read(struct net *net) |
| { |
| unsigned int h, fib_seq = 0; |
| |
| rcu_read_lock(); |
| for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { |
| struct hlist_head *head = &net->ipv6.fib_table_hash[h]; |
| struct fib6_table *tb; |
| |
| hlist_for_each_entry_rcu(tb, head, tb6_hlist) |
| fib_seq += tb->fib_seq; |
| } |
| rcu_read_unlock(); |
| |
| return fib_seq; |
| } |
| |
| static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net, |
| enum fib_event_type event_type, |
| struct fib6_info *rt) |
| { |
| struct fib6_entry_notifier_info info = { |
| .rt = rt, |
| }; |
| |
| return call_fib6_notifier(nb, net, event_type, &info.info); |
| } |
| |
| static int call_fib6_entry_notifiers(struct net *net, |
| enum fib_event_type event_type, |
| struct fib6_info *rt, |
| struct netlink_ext_ack *extack) |
| { |
| struct fib6_entry_notifier_info info = { |
| .info.extack = extack, |
| .rt = rt, |
| }; |
| |
| rt->fib6_table->fib_seq++; |
| return call_fib6_notifiers(net, event_type, &info.info); |
| } |
| |
| struct fib6_dump_arg { |
| struct net *net; |
| struct notifier_block *nb; |
| }; |
| |
| static void fib6_rt_dump(struct fib6_info *rt, struct fib6_dump_arg *arg) |
| { |
| if (rt == arg->net->ipv6.fib6_null_entry) |
| return; |
| call_fib6_entry_notifier(arg->nb, arg->net, FIB_EVENT_ENTRY_ADD, rt); |
| } |
| |
| static int fib6_node_dump(struct fib6_walker *w) |
| { |
| struct fib6_info *rt; |
| |
| for_each_fib6_walker_rt(w) |
| fib6_rt_dump(rt, w->args); |
| w->leaf = NULL; |
| return 0; |
| } |
| |
| static void fib6_table_dump(struct net *net, struct fib6_table *tb, |
| struct fib6_walker *w) |
| { |
| w->root = &tb->tb6_root; |
| spin_lock_bh(&tb->tb6_lock); |
| fib6_walk(net, w); |
| spin_unlock_bh(&tb->tb6_lock); |
| } |
| |
| /* Called with rcu_read_lock() */ |
| int fib6_tables_dump(struct net *net, struct notifier_block *nb) |
| { |
| struct fib6_dump_arg arg; |
| struct fib6_walker *w; |
| unsigned int h; |
| |
| w = kzalloc(sizeof(*w), GFP_ATOMIC); |
| if (!w) |
| return -ENOMEM; |
| |
| w->func = fib6_node_dump; |
| arg.net = net; |
| arg.nb = nb; |
| w->args = &arg; |
| |
| for (h = 0; h < FIB6_TABLE_HASHSZ; h++) { |
| struct hlist_head *head = &net->ipv6.fib_table_hash[h]; |
| struct fib6_table *tb; |
| |
| hlist_for_each_entry_rcu(tb, head, tb6_hlist) |
| fib6_table_dump(net, tb, w); |
| } |
| |
| kfree(w); |
| |
| return 0; |
| } |
| |
| static int fib6_dump_node(struct fib6_walker *w) |
| { |
| int res; |
| struct fib6_info *rt; |
| |
| for_each_fib6_walker_rt(w) { |
| res = rt6_dump_route(rt, w->args); |
| if (res < 0) { |
| /* Frame is full, suspend walking */ |
| w->leaf = rt; |
| return 1; |
| } |
| |
| /* Multipath routes are dumped in one route with the |
| * RTA_MULTIPATH attribute. Jump 'rt' to point to the |
| * last sibling of this route (no need to dump the |
| * sibling routes again) |
| */ |
| if (rt->fib6_nsiblings) |
| rt = list_last_entry(&rt->fib6_siblings, |
| struct fib6_info, |
| fib6_siblings); |
| } |
| w->leaf = NULL; |
| return 0; |
| } |
| |
| static void fib6_dump_end(struct netlink_callback *cb) |
| { |
| struct net *net = sock_net(cb->skb->sk); |
| struct fib6_walker *w = (void *)cb->args[2]; |
| |
| if (w) { |
| if (cb->args[4]) { |
| cb->args[4] = 0; |
| fib6_walker_unlink(net, w); |
| } |
| cb->args[2] = 0; |
| kfree(w); |
| } |
| cb->done = (void *)cb->args[3]; |
| cb->args[1] = 3; |
| } |
| |
| static int fib6_dump_done(struct netlink_callback *cb) |
| { |
| fib6_dump_end(cb); |
| return cb->done ? cb->done(cb) : 0; |
| } |
| |
| static int fib6_dump_table(struct fib6_table *table, struct sk_buff *skb, |
| struct netlink_callback *cb) |
| { |
| struct net *net = sock_net(skb->sk); |
| struct fib6_walker *w; |
| int res; |
| |
| w = (void *)cb->args[2]; |
| w->root = &table->tb6_root; |
| |
| if (cb->args[4] == 0) { |
| w->count = 0; |
| w->skip = 0; |
| |
| spin_lock_bh(&table->tb6_lock); |
| res = fib6_walk(net, w); |
| spin_unlock_bh(&table->tb6_lock); |
| if (res > 0) { |
| cb->args[4] = 1; |
| cb->args[5] = w->root->fn_sernum; |
| } |
| } else { |
| if (cb->args[5] != w->root->fn_sernum) { |
| /* Begin at the root if the tree changed */ |
| cb->args[5] = w->root->fn_sernum; |
| w->state = FWS_INIT; |
| w->node = w->root; |
| w->skip = w->count; |
| } else |
| w->skip = 0; |
| |
| spin_lock_bh(&table->tb6_lock); |
| res = fib6_walk_continue(w); |
| spin_unlock_bh(&table->tb6_lock); |
| if (res <= 0) { |
| fib6_walker_unlink(net, w); |
| cb->args[4] = 0; |
| } |
| } |
| |
| return res; |
| } |
| |
| static int inet6_dump_fib(struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| const struct nlmsghdr *nlh = cb->nlh; |
| struct net *net = sock_net(skb->sk); |
| struct rt6_rtnl_dump_arg arg = {}; |
| unsigned int h, s_h; |
| unsigned int e = 0, s_e; |
| struct fib6_walker *w; |
| struct fib6_table *tb; |
| struct hlist_head *head; |
| int res = 0; |
| |
| if (cb->strict_check) { |
| int err; |
| |
| err = ip_valid_fib_dump_req(net, nlh, &arg.filter, cb); |
| if (err < 0) |
| return err; |
| } else if (nlmsg_len(nlh) >= sizeof(struct rtmsg)) { |
| struct rtmsg *rtm = nlmsg_data(nlh); |
| |
| arg.filter.flags = rtm->rtm_flags & (RTM_F_PREFIX|RTM_F_CLONED); |
| } |
| |
| /* fib entries are never clones */ |
| if (arg.filter.flags & RTM_F_CLONED) |
| goto out; |
| |
| 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; |
| |
| if (arg.filter.table_id) { |
| tb = fib6_get_table(net, arg.filter.table_id); |
| if (!tb) { |
| if (arg.filter.dump_all_families) |
| goto out; |
| |
| NL_SET_ERR_MSG_MOD(cb->extack, "FIB table does not exist"); |
| return -ENOENT; |
| } |
| |
| if (!cb->args[0]) { |
| res = fib6_dump_table(tb, skb, cb); |
| if (!res) |
| cb->args[0] = 1; |
| } |
| goto out; |
| } |
| |
| s_h = cb->args[0]; |
| s_e = cb->args[1]; |
| |
| 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_unlock; |
| next: |
| e++; |
| } |
| } |
| out_unlock: |
| rcu_read_unlock(); |
| cb->args[1] = e; |
| cb->args[0] = h; |
| out: |
| res = res < 0 ? res : skb->len; |
| if (res <= 0) |
| fib6_dump_end(cb); |
| return res; |
| } |
| |
| void fib6_metric_set(struct fib6_info *f6i, int metric, u32 val) |
| { |
| if (!f6i) |
| return; |
| |
| if (f6i->fib6_metrics == &dst_default_metrics) { |
| struct dst_metrics *p = kzalloc(sizeof(*p), GFP_ATOMIC); |
| |
| if (!p) |
| return; |
| |
| refcount_set(&p->refcnt, 1); |
| f6i->fib6_metrics = p; |
| } |
| |
| f6i->fib6_metrics->metrics[metric - 1] = val; |
| } |
| |
| /* |
| * 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 fib6_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); |
| fib6_info_release(leaf); |
| /* remove null_entry in the root node */ |
| } else if (fn->fn_flags & RTN_TL_ROOT && |
| rcu_access_pointer(fn->leaf) == |
| net->ipv6.fib6_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; |
| fib6_info_hold(rcu_dereference_protected(in->leaf, |
| lockdep_is_held(&table->tb6_lock))); |
| |
| /* 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_drop_pcpu_from(struct fib6_info *f6i, |
| const struct fib6_table *table) |
| { |
| int cpu; |
| |
| /* release the reference to this fib entry from |
| * all of its cached pcpu routes |
| */ |
| for_each_possible_cpu(cpu) { |
| struct rt6_info **ppcpu_rt; |
| struct rt6_info *pcpu_rt; |
| |
| ppcpu_rt = per_cpu_ptr(f6i->rt6i_pcpu, cpu); |
| pcpu_rt = *ppcpu_rt; |
| if (pcpu_rt) { |
| struct fib6_info *from; |
| |
| from = xchg((__force struct fib6_info **)&pcpu_rt->from, NULL); |
| fib6_info_release(from); |
| } |
| } |
| } |
| |
| static void fib6_purge_rt(struct fib6_info *rt, struct fib6_node *fn, |
| struct net *net) |
| { |
| struct fib6_table *table = rt->fib6_table; |
| |
| if (refcount_read(&rt->fib6_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 fib6_info *leaf = rcu_dereference_protected(fn->leaf, |
| lockdep_is_held(&table->tb6_lock)); |
| struct fib6_info *new_leaf; |
| if (!(fn->fn_flags & RTN_RTINFO) && leaf == rt) { |
| new_leaf = fib6_find_prefix(net, table, fn); |
| fib6_info_hold(new_leaf); |
| |
| rcu_assign_pointer(fn->leaf, new_leaf); |
| fib6_info_release(rt); |
| } |
| fn = rcu_dereference_protected(fn->parent, |
| lockdep_is_held(&table->tb6_lock)); |
| } |
| |
| if (rt->rt6i_pcpu) |
| fib6_drop_pcpu_from(rt, table); |
| } |
| } |
| |
| /* |
| * Insert routing information in a node. |
| */ |
| |
| static int fib6_add_rt2node(struct fib6_node *fn, struct fib6_info *rt, |
| struct nl_info *info, |
| struct netlink_ext_ack *extack) |
| { |
| struct fib6_info *leaf = rcu_dereference_protected(fn->leaf, |
| lockdep_is_held(&rt->fib6_table->tb6_lock)); |
| struct fib6_info *iter = NULL; |
| struct fib6_info __rcu **ins; |
| struct fib6_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->fib6_next, |
| lockdep_is_held(&rt->fib6_table->tb6_lock))) { |
| /* |
| * Search for duplicates |
| */ |
| |
| if (iter->fib6_metric == rt->fib6_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->fib6_nsiblings) |
| rt->fib6_nsiblings = 0; |
| if (!(iter->fib6_flags & RTF_EXPIRES)) |
| return -EEXIST; |
| if (!(rt->fib6_flags & RTF_EXPIRES)) |
| fib6_clean_expires(iter); |
| else |
| fib6_set_expires(iter, rt->expires); |
| |
| if (rt->fib6_pmtu) |
| fib6_metric_set(iter, RTAX_MTU, |
| rt->fib6_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->fib6_nsiblings++; |
| } |
| |
| if (iter->fib6_metric > rt->fib6_metric) |
| break; |
| |
| next_iter: |
| ins = &iter->fib6_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->fib6_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->fib6_nsiblings) { |
| unsigned int fib6_nsiblings; |
| struct fib6_info *sibling, *temp_sibling; |
| |
| /* Find the first route that have the same metric */ |
| sibling = leaf; |
| while (sibling) { |
| if (sibling->fib6_metric == rt->fib6_metric && |
| rt6_qualify_for_ecmp(sibling)) { |
| list_add_tail(&rt->fib6_siblings, |
| &sibling->fib6_siblings); |
| break; |
| } |
| sibling = rcu_dereference_protected(sibling->fib6_next, |
| lockdep_is_held(&rt->fib6_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! |
| */ |
| fib6_nsiblings = 0; |
| list_for_each_entry_safe(sibling, temp_sibling, |
| &rt->fib6_siblings, fib6_siblings) { |
| sibling->fib6_nsiblings++; |
| BUG_ON(sibling->fib6_nsiblings != rt->fib6_nsiblings); |
| fib6_nsiblings++; |
| } |
| BUG_ON(fib6_nsiblings != rt->fib6_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 = call_fib6_entry_notifiers(info->nl_net, |
| FIB_EVENT_ENTRY_ADD, |
| rt, extack); |
| if (err) |
| return err; |
| |
| rcu_assign_pointer(rt->fib6_next, iter); |
| fib6_info_hold(rt); |
| rcu_assign_pointer(rt->fib6_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 = call_fib6_entry_notifiers(info->nl_net, |
| FIB_EVENT_ENTRY_REPLACE, |
| rt, extack); |
| if (err) |
| return err; |
| |
| fib6_info_hold(rt); |
| rcu_assign_pointer(rt->fib6_node, fn); |
| rt->fib6_next = iter->fib6_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->fib6_nsiblings; |
| iter->fib6_node = NULL; |
| fib6_purge_rt(iter, fn, info->nl_net); |
| if (rcu_access_pointer(fn->rr_ptr) == iter) |
| fn->rr_ptr = NULL; |
| fib6_info_release(iter); |
| |
| if (nsiblings) { |
| /* Replacing an ECMP route, remove all siblings */ |
| ins = &rt->fib6_next; |
| iter = rcu_dereference_protected(*ins, |
| lockdep_is_held(&rt->fib6_table->tb6_lock)); |
| while (iter) { |
| if (iter->fib6_metric > rt->fib6_metric) |
| break; |
| if (rt6_qualify_for_ecmp(iter)) { |
| *ins = iter->fib6_next; |
| iter->fib6_node = NULL; |
| fib6_purge_rt(iter, fn, info->nl_net); |
| if (rcu_access_pointer(fn->rr_ptr) == iter) |
| fn->rr_ptr = NULL; |
| fib6_info_release(iter); |
| nsiblings--; |
| info->nl_net->ipv6.rt6_stats->fib_rt_entries--; |
| } else { |
| ins = &iter->fib6_next; |
| } |
| iter = rcu_dereference_protected(*ins, |
| lockdep_is_held(&rt->fib6_table->tb6_lock)); |
| } |
| WARN_ON(nsiblings != 0); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static void fib6_start_gc(struct net *net, struct fib6_info *rt) |
| { |
| if (!timer_pending(&net->ipv6.ip6_fib_timer) && |
| (rt->fib6_flags & RTF_EXPIRES)) |
| 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 fib6_info *rt, |
| int sernum) |
| { |
| struct fib6_node *fn = rcu_dereference_protected(rt->fib6_node, |
| lockdep_is_held(&rt->fib6_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->fib6_table->tb6_lock)); |
| } |
| } |
| |
| void fib6_update_sernum_upto_root(struct net *net, struct fib6_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 fib6_info *rt, |
| struct nl_info *info, struct netlink_ext_ack *extack) |
| { |
| struct fib6_table *table = rt->fib6_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 (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->fib6_dst.addr, rt->fib6_dst.plen, |
| offsetof(struct fib6_info, fib6_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->fib6_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; |
| |
| fib6_info_hold(info->nl_net->ipv6.fib6_null_entry); |
| rcu_assign_pointer(sfn->leaf, |
| info->nl_net->ipv6.fib6_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->fib6_src.addr, rt->fib6_src.plen, |
| offsetof(struct fib6_info, fib6_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->fib6_src.addr, rt->fib6_src.plen, |
| offsetof(struct fib6_info, fib6_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.fib6_null_entry); |
| } else { |
| fib6_info_hold(rt); |
| rcu_assign_pointer(fn->leaf, rt); |
| } |
| } |
| fn = sn; |
| } |
| #endif |
| |
| err = fib6_add_rt2node(fn, rt, info, 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 fib6_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); |
| fib6_info_release(rt); |
| } |
| 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.fib6_null_entry; |
| } |
| #endif |
| fib6_info_hold(pn_leaf); |
| 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); |
| return err; |
| } |
| |
| /* |
| * Routing tree lookup |
| * |
| */ |
| |
| struct lookup_args { |
| int offset; /* key offset on fib6_info */ |
| const struct in6_addr *addr; /* search key */ |
| }; |
| |
| static struct fib6_node *fib6_node_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 fib6_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_node_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_node_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 fib6_info, fib6_dst), |
| .addr = daddr, |
| }, |
| #ifdef CONFIG_IPV6_SUBTREES |
| { |
| .offset = offsetof(struct fib6_info, fib6_src), |
| .addr = saddr, |
| }, |
| #endif |
| { |
| .offset = 0, /* sentinel */ |
| } |
| }; |
| |
| fn = fib6_node_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 fib6_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 fib6_info, fib6_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 fib6_info, fib6_src), |
| exact_match); |
| } |
| } |
| } |
| #endif |
| |
| if (fn && fn->fn_flags & RTN_RTINFO) |
| return fn; |
| |
| return NULL; |
| } |
| |
| |
| /* |
| * Deletion |
| * |
| */ |
| |
| static struct fib6_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.fib6_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.fib6_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 fib6_info *fn_leaf = rcu_dereference_protected(fn->leaf, |
| lockdep_is_held(&table->tb6_lock)); |
| struct fib6_info *pn_leaf = rcu_dereference_protected(pn->leaf, |
| lockdep_is_held(&table->tb6_lock)); |
| struct fib6_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.fib6_null_entry; |
| } |
| #endif |
| fib6_info_hold(new_fn_leaf); |
| 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); |
| fib6_info_release(pn_leaf); |
| fn = pn; |
| } |
| } |
| |
| static void fib6_del_route(struct fib6_table *table, struct fib6_node *fn, |
| struct fib6_info __rcu **rtp, struct nl_info *info) |
| { |
| struct fib6_walker *w; |
| struct fib6_info *rt = rcu_dereference_protected(*rtp, |
| lockdep_is_held(&table->tb6_lock)); |
| struct net *net = info->nl_net; |
| |
| RT6_TRACE("fib6_del_route\n"); |
| |
| /* Unlink it */ |
| *rtp = rt->fib6_next; |
| rt->fib6_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->fib6_nsiblings) { |
| struct fib6_info *sibling, *next_sibling; |
| |
| list_for_each_entry_safe(sibling, next_sibling, |
| &rt->fib6_siblings, fib6_siblings) |
| sibling->fib6_nsiblings--; |
| rt->fib6_nsiblings = 0; |
| list_del_init(&rt->fib6_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->fib6_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); |
| fib6_info_release(rt); |
| } |
| |
| /* Need to own table->tb6_lock */ |
| int fib6_del(struct fib6_info *rt, struct nl_info *info) |
| { |
| struct fib6_node *fn = rcu_dereference_protected(rt->fib6_node, |
| lockdep_is_held(&rt->fib6_table->tb6_lock)); |
| struct fib6_table *table = rt->fib6_table; |
| struct net *net = info->nl_net; |
| struct fib6_info __rcu **rtp; |
| struct fib6_info __rcu **rtp_next; |
| |
| if (!fn || rt == net->ipv6.fib6_null_entry) |
| return -ENOENT; |
| |
| WARN_ON(!(fn->fn_flags & RTN_RTINFO)); |
| |
| /* |
| * Walk the leaf entries looking for ourself |
| */ |
| |
| for (rtp = &fn->leaf; *rtp; rtp = rtp_next) { |
| struct fib6_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->fib6_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 fib6_info *rt; |
| struct fib6_cleaner *c = container_of(w, struct fib6_cleaner, w); |
| struct nl_info info = { |
| .nl_net = c->net, |
| .skip_notify = c->skip_notify, |
| }; |
| |
| 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->fib6_node), |
| res); |
| #endif |
| continue; |
| } |
| return 0; |
| } else if (res == -2) { |
| if (WARN_ON(!rt->fib6_nsiblings)) |
| continue; |
| rt = list_last_entry(&rt->fib6_siblings, |
| struct fib6_info, fib6_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 fib6_info *, void *arg), |
| int sernum, void *arg, bool skip_notify) |
| { |
| 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; |
| c.skip_notify = skip_notify; |
| |
| fib6_walk(net, &c.w); |
| } |
| |
| static void __fib6_clean_all(struct net *net, |
| int (*func)(struct fib6_info *, void *), |
| int sernum, void *arg, bool skip_notify) |
| { |
| 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, skip_notify); |
| spin_unlock_bh(&table->tb6_lock); |
| } |
| } |
| rcu_read_unlock(); |
| } |
| |
| void fib6_clean_all(struct net *net, int (*func)(struct fib6_info *, void *), |
| void *arg) |
| { |
| __fib6_clean_all(net, func, FIB6_NO_SERNUM_CHANGE, arg, false); |
| } |
| |
| void fib6_clean_all_skip_notify(struct net *net, |
| int (*func)(struct fib6_info *, void *), |
| void *arg) |
| { |
| __fib6_clean_all(net, func, FIB6_NO_SERNUM_CHANGE, arg, true); |
| } |
| |
| static void fib6_flush_trees(struct net *net) |
| { |
| int new_sernum = fib6_new_sernum(net); |
| |
| __fib6_clean_all(net, NULL, new_sernum, NULL, false); |
| } |
| |
| /* |
| * Garbage collection |
| */ |
| |
| static int fib6_age(struct fib6_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->fib6_flags & RTF_EXPIRES && rt->expires) { |
| if (time_after(now, rt->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.fib6_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.fib6_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 |
| static int ipv6_route_seq_show(struct seq_file *seq, void *v) |
| { |
| struct fib6_info *rt = v; |
| struct ipv6_route_iter *iter = seq->private; |
| unsigned int flags = rt->fib6_flags; |
| const struct net_device *dev; |
| |
| seq_printf(seq, "%pi6 %02x ", &rt->fib6_dst.addr, rt->fib6_dst.plen); |
| |
| #ifdef CONFIG_IPV6_SUBTREES |
| seq_printf(seq, "%pi6 %02x ", &rt->fib6_src.addr, rt->fib6_src.plen); |
| #else |
| seq_puts(seq, "00000000000000000000000000000000 00 "); |
| #endif |
| if (rt->fib6_nh.fib_nh_gw_family) { |
| flags |= RTF_GATEWAY; |
| seq_printf(seq, "%pi6", &rt->fib6_nh.fib_nh_gw6); |
| } else { |
| seq_puts(seq, "00000000000000000000000000000000"); |
| } |
| |
| dev = rt->fib6_nh.fib_nh_dev; |
| seq_printf(seq, " %08x %08x %08x %08x %8s\n", |
| rt->fib6_metric, refcount_read(&rt->fib6_ref), 0, |
| flags, dev ? 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->fib6_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 fib6_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 fib6_info *)v)->fib6_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(); |
| } |
| |
| 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 |
| }; |
| #endif /* CONFIG_PROC_FS */ |