| /* |
| * 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. |
| * |
| * Robert Olsson <robert.olsson@its.uu.se> Uppsala Universitet |
| * & Swedish University of Agricultural Sciences. |
| * |
| * Jens Laas <jens.laas@data.slu.se> Swedish University of |
| * Agricultural Sciences. |
| * |
| * Hans Liss <hans.liss@its.uu.se> Uppsala Universitet |
| * |
| * This work is based on the LPC-trie which is originally described in: |
| * |
| * An experimental study of compression methods for dynamic tries |
| * Stefan Nilsson and Matti Tikkanen. Algorithmica, 33(1):19-33, 2002. |
| * http://www.csc.kth.se/~snilsson/software/dyntrie2/ |
| * |
| * |
| * IP-address lookup using LC-tries. Stefan Nilsson and Gunnar Karlsson |
| * IEEE Journal on Selected Areas in Communications, 17(6):1083-1092, June 1999 |
| * |
| * |
| * Code from fib_hash has been reused which includes the following header: |
| * |
| * |
| * INET An implementation of the TCP/IP protocol suite for the LINUX |
| * operating system. INET is implemented using the BSD Socket |
| * interface as the means of communication with the user level. |
| * |
| * IPv4 FIB: lookup engine and maintenance routines. |
| * |
| * |
| * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru> |
| * |
| * 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. |
| * |
| * Substantial contributions to this work comes from: |
| * |
| * David S. Miller, <davem@davemloft.net> |
| * Stephen Hemminger <shemminger@osdl.org> |
| * Paul E. McKenney <paulmck@us.ibm.com> |
| * Patrick McHardy <kaber@trash.net> |
| */ |
| |
| #define VERSION "0.409" |
| |
| #include <asm/uaccess.h> |
| #include <linux/bitops.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/mm.h> |
| #include <linux/string.h> |
| #include <linux/socket.h> |
| #include <linux/sockios.h> |
| #include <linux/errno.h> |
| #include <linux/in.h> |
| #include <linux/inet.h> |
| #include <linux/inetdevice.h> |
| #include <linux/netdevice.h> |
| #include <linux/if_arp.h> |
| #include <linux/proc_fs.h> |
| #include <linux/rcupdate.h> |
| #include <linux/skbuff.h> |
| #include <linux/netlink.h> |
| #include <linux/init.h> |
| #include <linux/list.h> |
| #include <linux/slab.h> |
| #include <linux/prefetch.h> |
| #include <linux/export.h> |
| #include <net/net_namespace.h> |
| #include <net/ip.h> |
| #include <net/protocol.h> |
| #include <net/route.h> |
| #include <net/tcp.h> |
| #include <net/sock.h> |
| #include <net/ip_fib.h> |
| #include "fib_lookup.h" |
| |
| #define MAX_STAT_DEPTH 32 |
| |
| #define KEYLENGTH (8*sizeof(t_key)) |
| |
| typedef unsigned int t_key; |
| |
| #define T_TNODE 0 |
| #define T_LEAF 1 |
| #define NODE_TYPE_MASK 0x1UL |
| #define NODE_TYPE(node) ((node)->parent & NODE_TYPE_MASK) |
| |
| #define IS_TNODE(n) (!(n->parent & T_LEAF)) |
| #define IS_LEAF(n) (n->parent & T_LEAF) |
| |
| struct rt_trie_node { |
| unsigned long parent; |
| t_key key; |
| }; |
| |
| struct leaf { |
| unsigned long parent; |
| t_key key; |
| struct hlist_head list; |
| struct rcu_head rcu; |
| }; |
| |
| struct leaf_info { |
| struct hlist_node hlist; |
| int plen; |
| u32 mask_plen; /* ntohl(inet_make_mask(plen)) */ |
| struct list_head falh; |
| struct rcu_head rcu; |
| }; |
| |
| struct tnode { |
| unsigned long parent; |
| t_key key; |
| unsigned char pos; /* 2log(KEYLENGTH) bits needed */ |
| unsigned char bits; /* 2log(KEYLENGTH) bits needed */ |
| unsigned int full_children; /* KEYLENGTH bits needed */ |
| unsigned int empty_children; /* KEYLENGTH bits needed */ |
| union { |
| struct rcu_head rcu; |
| struct work_struct work; |
| struct tnode *tnode_free; |
| }; |
| struct rt_trie_node __rcu *child[0]; |
| }; |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| struct trie_use_stats { |
| unsigned int gets; |
| unsigned int backtrack; |
| unsigned int semantic_match_passed; |
| unsigned int semantic_match_miss; |
| unsigned int null_node_hit; |
| unsigned int resize_node_skipped; |
| }; |
| #endif |
| |
| struct trie_stat { |
| unsigned int totdepth; |
| unsigned int maxdepth; |
| unsigned int tnodes; |
| unsigned int leaves; |
| unsigned int nullpointers; |
| unsigned int prefixes; |
| unsigned int nodesizes[MAX_STAT_DEPTH]; |
| }; |
| |
| struct trie { |
| struct rt_trie_node __rcu *trie; |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| struct trie_use_stats stats; |
| #endif |
| }; |
| |
| static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n, |
| int wasfull); |
| static struct rt_trie_node *resize(struct trie *t, struct tnode *tn); |
| static struct tnode *inflate(struct trie *t, struct tnode *tn); |
| static struct tnode *halve(struct trie *t, struct tnode *tn); |
| /* tnodes to free after resize(); protected by RTNL */ |
| static struct tnode *tnode_free_head; |
| static size_t tnode_free_size; |
| |
| /* |
| * synchronize_rcu after call_rcu for that many pages; it should be especially |
| * useful before resizing the root node with PREEMPT_NONE configs; the value was |
| * obtained experimentally, aiming to avoid visible slowdown. |
| */ |
| static const int sync_pages = 128; |
| |
| static struct kmem_cache *fn_alias_kmem __read_mostly; |
| static struct kmem_cache *trie_leaf_kmem __read_mostly; |
| |
| /* |
| * caller must hold RTNL |
| */ |
| static inline struct tnode *node_parent(const struct rt_trie_node *node) |
| { |
| unsigned long parent; |
| |
| parent = rcu_dereference_index_check(node->parent, lockdep_rtnl_is_held()); |
| |
| return (struct tnode *)(parent & ~NODE_TYPE_MASK); |
| } |
| |
| /* |
| * caller must hold RCU read lock or RTNL |
| */ |
| static inline struct tnode *node_parent_rcu(const struct rt_trie_node *node) |
| { |
| unsigned long parent; |
| |
| parent = rcu_dereference_index_check(node->parent, rcu_read_lock_held() || |
| lockdep_rtnl_is_held()); |
| |
| return (struct tnode *)(parent & ~NODE_TYPE_MASK); |
| } |
| |
| /* Same as rcu_assign_pointer |
| * but that macro() assumes that value is a pointer. |
| */ |
| static inline void node_set_parent(struct rt_trie_node *node, struct tnode *ptr) |
| { |
| smp_wmb(); |
| node->parent = (unsigned long)ptr | NODE_TYPE(node); |
| } |
| |
| /* |
| * caller must hold RTNL |
| */ |
| static inline struct rt_trie_node *tnode_get_child(const struct tnode *tn, unsigned int i) |
| { |
| BUG_ON(i >= 1U << tn->bits); |
| |
| return rtnl_dereference(tn->child[i]); |
| } |
| |
| /* |
| * caller must hold RCU read lock or RTNL |
| */ |
| static inline struct rt_trie_node *tnode_get_child_rcu(const struct tnode *tn, unsigned int i) |
| { |
| BUG_ON(i >= 1U << tn->bits); |
| |
| return rcu_dereference_rtnl(tn->child[i]); |
| } |
| |
| static inline int tnode_child_length(const struct tnode *tn) |
| { |
| return 1 << tn->bits; |
| } |
| |
| static inline t_key mask_pfx(t_key k, unsigned int l) |
| { |
| return (l == 0) ? 0 : k >> (KEYLENGTH-l) << (KEYLENGTH-l); |
| } |
| |
| static inline t_key tkey_extract_bits(t_key a, unsigned int offset, unsigned int bits) |
| { |
| if (offset < KEYLENGTH) |
| return ((t_key)(a << offset)) >> (KEYLENGTH - bits); |
| else |
| return 0; |
| } |
| |
| static inline int tkey_equals(t_key a, t_key b) |
| { |
| return a == b; |
| } |
| |
| static inline int tkey_sub_equals(t_key a, int offset, int bits, t_key b) |
| { |
| if (bits == 0 || offset >= KEYLENGTH) |
| return 1; |
| bits = bits > KEYLENGTH ? KEYLENGTH : bits; |
| return ((a ^ b) << offset) >> (KEYLENGTH - bits) == 0; |
| } |
| |
| static inline int tkey_mismatch(t_key a, int offset, t_key b) |
| { |
| t_key diff = a ^ b; |
| int i = offset; |
| |
| if (!diff) |
| return 0; |
| while ((diff << i) >> (KEYLENGTH-1) == 0) |
| i++; |
| return i; |
| } |
| |
| /* |
| To understand this stuff, an understanding of keys and all their bits is |
| necessary. Every node in the trie has a key associated with it, but not |
| all of the bits in that key are significant. |
| |
| Consider a node 'n' and its parent 'tp'. |
| |
| If n is a leaf, every bit in its key is significant. Its presence is |
| necessitated by path compression, since during a tree traversal (when |
| searching for a leaf - unless we are doing an insertion) we will completely |
| ignore all skipped bits we encounter. Thus we need to verify, at the end of |
| a potentially successful search, that we have indeed been walking the |
| correct key path. |
| |
| Note that we can never "miss" the correct key in the tree if present by |
| following the wrong path. Path compression ensures that segments of the key |
| that are the same for all keys with a given prefix are skipped, but the |
| skipped part *is* identical for each node in the subtrie below the skipped |
| bit! trie_insert() in this implementation takes care of that - note the |
| call to tkey_sub_equals() in trie_insert(). |
| |
| if n is an internal node - a 'tnode' here, the various parts of its key |
| have many different meanings. |
| |
| Example: |
| _________________________________________________________________ |
| | i | i | i | i | i | i | i | N | N | N | S | S | S | S | S | C | |
| ----------------------------------------------------------------- |
| 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 |
| |
| _________________________________________________________________ |
| | C | C | C | u | u | u | u | u | u | u | u | u | u | u | u | u | |
| ----------------------------------------------------------------- |
| 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 |
| |
| tp->pos = 7 |
| tp->bits = 3 |
| n->pos = 15 |
| n->bits = 4 |
| |
| First, let's just ignore the bits that come before the parent tp, that is |
| the bits from 0 to (tp->pos-1). They are *known* but at this point we do |
| not use them for anything. |
| |
| The bits from (tp->pos) to (tp->pos + tp->bits - 1) - "N", above - are the |
| index into the parent's child array. That is, they will be used to find |
| 'n' among tp's children. |
| |
| The bits from (tp->pos + tp->bits) to (n->pos - 1) - "S" - are skipped bits |
| for the node n. |
| |
| All the bits we have seen so far are significant to the node n. The rest |
| of the bits are really not needed or indeed known in n->key. |
| |
| The bits from (n->pos) to (n->pos + n->bits - 1) - "C" - are the index into |
| n's child array, and will of course be different for each child. |
| |
| |
| The rest of the bits, from (n->pos + n->bits) onward, are completely unknown |
| at this point. |
| |
| */ |
| |
| static inline void check_tnode(const struct tnode *tn) |
| { |
| WARN_ON(tn && tn->pos+tn->bits > 32); |
| } |
| |
| static const int halve_threshold = 25; |
| static const int inflate_threshold = 50; |
| static const int halve_threshold_root = 15; |
| static const int inflate_threshold_root = 30; |
| |
| static void __alias_free_mem(struct rcu_head *head) |
| { |
| struct fib_alias *fa = container_of(head, struct fib_alias, rcu); |
| kmem_cache_free(fn_alias_kmem, fa); |
| } |
| |
| static inline void alias_free_mem_rcu(struct fib_alias *fa) |
| { |
| call_rcu(&fa->rcu, __alias_free_mem); |
| } |
| |
| static void __leaf_free_rcu(struct rcu_head *head) |
| { |
| struct leaf *l = container_of(head, struct leaf, rcu); |
| kmem_cache_free(trie_leaf_kmem, l); |
| } |
| |
| static inline void free_leaf(struct leaf *l) |
| { |
| call_rcu_bh(&l->rcu, __leaf_free_rcu); |
| } |
| |
| static inline void free_leaf_info(struct leaf_info *leaf) |
| { |
| kfree_rcu(leaf, rcu); |
| } |
| |
| static struct tnode *tnode_alloc(size_t size) |
| { |
| if (size <= PAGE_SIZE) |
| return kzalloc(size, GFP_KERNEL); |
| else |
| return vzalloc(size); |
| } |
| |
| static void __tnode_vfree(struct work_struct *arg) |
| { |
| struct tnode *tn = container_of(arg, struct tnode, work); |
| vfree(tn); |
| } |
| |
| static void __tnode_free_rcu(struct rcu_head *head) |
| { |
| struct tnode *tn = container_of(head, struct tnode, rcu); |
| size_t size = sizeof(struct tnode) + |
| (sizeof(struct rt_trie_node *) << tn->bits); |
| |
| if (size <= PAGE_SIZE) |
| kfree(tn); |
| else { |
| INIT_WORK(&tn->work, __tnode_vfree); |
| schedule_work(&tn->work); |
| } |
| } |
| |
| static inline void tnode_free(struct tnode *tn) |
| { |
| if (IS_LEAF(tn)) |
| free_leaf((struct leaf *) tn); |
| else |
| call_rcu(&tn->rcu, __tnode_free_rcu); |
| } |
| |
| static void tnode_free_safe(struct tnode *tn) |
| { |
| BUG_ON(IS_LEAF(tn)); |
| tn->tnode_free = tnode_free_head; |
| tnode_free_head = tn; |
| tnode_free_size += sizeof(struct tnode) + |
| (sizeof(struct rt_trie_node *) << tn->bits); |
| } |
| |
| static void tnode_free_flush(void) |
| { |
| struct tnode *tn; |
| |
| while ((tn = tnode_free_head)) { |
| tnode_free_head = tn->tnode_free; |
| tn->tnode_free = NULL; |
| tnode_free(tn); |
| } |
| |
| if (tnode_free_size >= PAGE_SIZE * sync_pages) { |
| tnode_free_size = 0; |
| synchronize_rcu(); |
| } |
| } |
| |
| static struct leaf *leaf_new(void) |
| { |
| struct leaf *l = kmem_cache_alloc(trie_leaf_kmem, GFP_KERNEL); |
| if (l) { |
| l->parent = T_LEAF; |
| INIT_HLIST_HEAD(&l->list); |
| } |
| return l; |
| } |
| |
| static struct leaf_info *leaf_info_new(int plen) |
| { |
| struct leaf_info *li = kmalloc(sizeof(struct leaf_info), GFP_KERNEL); |
| if (li) { |
| li->plen = plen; |
| li->mask_plen = ntohl(inet_make_mask(plen)); |
| INIT_LIST_HEAD(&li->falh); |
| } |
| return li; |
| } |
| |
| static struct tnode *tnode_new(t_key key, int pos, int bits) |
| { |
| size_t sz = sizeof(struct tnode) + (sizeof(struct rt_trie_node *) << bits); |
| struct tnode *tn = tnode_alloc(sz); |
| |
| if (tn) { |
| tn->parent = T_TNODE; |
| tn->pos = pos; |
| tn->bits = bits; |
| tn->key = key; |
| tn->full_children = 0; |
| tn->empty_children = 1<<bits; |
| } |
| |
| pr_debug("AT %p s=%zu %zu\n", tn, sizeof(struct tnode), |
| sizeof(struct rt_trie_node *) << bits); |
| return tn; |
| } |
| |
| /* |
| * Check whether a tnode 'n' is "full", i.e. it is an internal node |
| * and no bits are skipped. See discussion in dyntree paper p. 6 |
| */ |
| |
| static inline int tnode_full(const struct tnode *tn, const struct rt_trie_node *n) |
| { |
| if (n == NULL || IS_LEAF(n)) |
| return 0; |
| |
| return ((struct tnode *) n)->pos == tn->pos + tn->bits; |
| } |
| |
| static inline void put_child(struct tnode *tn, int i, |
| struct rt_trie_node *n) |
| { |
| tnode_put_child_reorg(tn, i, n, -1); |
| } |
| |
| /* |
| * Add a child at position i overwriting the old value. |
| * Update the value of full_children and empty_children. |
| */ |
| |
| static void tnode_put_child_reorg(struct tnode *tn, int i, struct rt_trie_node *n, |
| int wasfull) |
| { |
| struct rt_trie_node *chi = rtnl_dereference(tn->child[i]); |
| int isfull; |
| |
| BUG_ON(i >= 1<<tn->bits); |
| |
| /* update emptyChildren */ |
| if (n == NULL && chi != NULL) |
| tn->empty_children++; |
| else if (n != NULL && chi == NULL) |
| tn->empty_children--; |
| |
| /* update fullChildren */ |
| if (wasfull == -1) |
| wasfull = tnode_full(tn, chi); |
| |
| isfull = tnode_full(tn, n); |
| if (wasfull && !isfull) |
| tn->full_children--; |
| else if (!wasfull && isfull) |
| tn->full_children++; |
| |
| if (n) |
| node_set_parent(n, tn); |
| |
| rcu_assign_pointer(tn->child[i], n); |
| } |
| |
| #define MAX_WORK 10 |
| static struct rt_trie_node *resize(struct trie *t, struct tnode *tn) |
| { |
| int i; |
| struct tnode *old_tn; |
| int inflate_threshold_use; |
| int halve_threshold_use; |
| int max_work; |
| |
| if (!tn) |
| return NULL; |
| |
| pr_debug("In tnode_resize %p inflate_threshold=%d threshold=%d\n", |
| tn, inflate_threshold, halve_threshold); |
| |
| /* No children */ |
| if (tn->empty_children == tnode_child_length(tn)) { |
| tnode_free_safe(tn); |
| return NULL; |
| } |
| /* One child */ |
| if (tn->empty_children == tnode_child_length(tn) - 1) |
| goto one_child; |
| /* |
| * Double as long as the resulting node has a number of |
| * nonempty nodes that are above the threshold. |
| */ |
| |
| /* |
| * From "Implementing a dynamic compressed trie" by Stefan Nilsson of |
| * the Helsinki University of Technology and Matti Tikkanen of Nokia |
| * Telecommunications, page 6: |
| * "A node is doubled if the ratio of non-empty children to all |
| * children in the *doubled* node is at least 'high'." |
| * |
| * 'high' in this instance is the variable 'inflate_threshold'. It |
| * is expressed as a percentage, so we multiply it with |
| * tnode_child_length() and instead of multiplying by 2 (since the |
| * child array will be doubled by inflate()) and multiplying |
| * the left-hand side by 100 (to handle the percentage thing) we |
| * multiply the left-hand side by 50. |
| * |
| * The left-hand side may look a bit weird: tnode_child_length(tn) |
| * - tn->empty_children is of course the number of non-null children |
| * in the current node. tn->full_children is the number of "full" |
| * children, that is non-null tnodes with a skip value of 0. |
| * All of those will be doubled in the resulting inflated tnode, so |
| * we just count them one extra time here. |
| * |
| * A clearer way to write this would be: |
| * |
| * to_be_doubled = tn->full_children; |
| * not_to_be_doubled = tnode_child_length(tn) - tn->empty_children - |
| * tn->full_children; |
| * |
| * new_child_length = tnode_child_length(tn) * 2; |
| * |
| * new_fill_factor = 100 * (not_to_be_doubled + 2*to_be_doubled) / |
| * new_child_length; |
| * if (new_fill_factor >= inflate_threshold) |
| * |
| * ...and so on, tho it would mess up the while () loop. |
| * |
| * anyway, |
| * 100 * (not_to_be_doubled + 2*to_be_doubled) / new_child_length >= |
| * inflate_threshold |
| * |
| * avoid a division: |
| * 100 * (not_to_be_doubled + 2*to_be_doubled) >= |
| * inflate_threshold * new_child_length |
| * |
| * expand not_to_be_doubled and to_be_doubled, and shorten: |
| * 100 * (tnode_child_length(tn) - tn->empty_children + |
| * tn->full_children) >= inflate_threshold * new_child_length |
| * |
| * expand new_child_length: |
| * 100 * (tnode_child_length(tn) - tn->empty_children + |
| * tn->full_children) >= |
| * inflate_threshold * tnode_child_length(tn) * 2 |
| * |
| * shorten again: |
| * 50 * (tn->full_children + tnode_child_length(tn) - |
| * tn->empty_children) >= inflate_threshold * |
| * tnode_child_length(tn) |
| * |
| */ |
| |
| check_tnode(tn); |
| |
| /* Keep root node larger */ |
| |
| if (!node_parent((struct rt_trie_node *)tn)) { |
| inflate_threshold_use = inflate_threshold_root; |
| halve_threshold_use = halve_threshold_root; |
| } else { |
| inflate_threshold_use = inflate_threshold; |
| halve_threshold_use = halve_threshold; |
| } |
| |
| max_work = MAX_WORK; |
| while ((tn->full_children > 0 && max_work-- && |
| 50 * (tn->full_children + tnode_child_length(tn) |
| - tn->empty_children) |
| >= inflate_threshold_use * tnode_child_length(tn))) { |
| |
| old_tn = tn; |
| tn = inflate(t, tn); |
| |
| if (IS_ERR(tn)) { |
| tn = old_tn; |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.resize_node_skipped++; |
| #endif |
| break; |
| } |
| } |
| |
| check_tnode(tn); |
| |
| /* Return if at least one inflate is run */ |
| if (max_work != MAX_WORK) |
| return (struct rt_trie_node *) tn; |
| |
| /* |
| * Halve as long as the number of empty children in this |
| * node is above threshold. |
| */ |
| |
| max_work = MAX_WORK; |
| while (tn->bits > 1 && max_work-- && |
| 100 * (tnode_child_length(tn) - tn->empty_children) < |
| halve_threshold_use * tnode_child_length(tn)) { |
| |
| old_tn = tn; |
| tn = halve(t, tn); |
| if (IS_ERR(tn)) { |
| tn = old_tn; |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.resize_node_skipped++; |
| #endif |
| break; |
| } |
| } |
| |
| |
| /* Only one child remains */ |
| if (tn->empty_children == tnode_child_length(tn) - 1) { |
| one_child: |
| for (i = 0; i < tnode_child_length(tn); i++) { |
| struct rt_trie_node *n; |
| |
| n = rtnl_dereference(tn->child[i]); |
| if (!n) |
| continue; |
| |
| /* compress one level */ |
| |
| node_set_parent(n, NULL); |
| tnode_free_safe(tn); |
| return n; |
| } |
| } |
| return (struct rt_trie_node *) tn; |
| } |
| |
| |
| static void tnode_clean_free(struct tnode *tn) |
| { |
| int i; |
| struct tnode *tofree; |
| |
| for (i = 0; i < tnode_child_length(tn); i++) { |
| tofree = (struct tnode *)rtnl_dereference(tn->child[i]); |
| if (tofree) |
| tnode_free(tofree); |
| } |
| tnode_free(tn); |
| } |
| |
| static struct tnode *inflate(struct trie *t, struct tnode *tn) |
| { |
| struct tnode *oldtnode = tn; |
| int olen = tnode_child_length(tn); |
| int i; |
| |
| pr_debug("In inflate\n"); |
| |
| tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits + 1); |
| |
| if (!tn) |
| return ERR_PTR(-ENOMEM); |
| |
| /* |
| * Preallocate and store tnodes before the actual work so we |
| * don't get into an inconsistent state if memory allocation |
| * fails. In case of failure we return the oldnode and inflate |
| * of tnode is ignored. |
| */ |
| |
| for (i = 0; i < olen; i++) { |
| struct tnode *inode; |
| |
| inode = (struct tnode *) tnode_get_child(oldtnode, i); |
| if (inode && |
| IS_TNODE(inode) && |
| inode->pos == oldtnode->pos + oldtnode->bits && |
| inode->bits > 1) { |
| struct tnode *left, *right; |
| t_key m = ~0U << (KEYLENGTH - 1) >> inode->pos; |
| |
| left = tnode_new(inode->key&(~m), inode->pos + 1, |
| inode->bits - 1); |
| if (!left) |
| goto nomem; |
| |
| right = tnode_new(inode->key|m, inode->pos + 1, |
| inode->bits - 1); |
| |
| if (!right) { |
| tnode_free(left); |
| goto nomem; |
| } |
| |
| put_child(tn, 2*i, (struct rt_trie_node *) left); |
| put_child(tn, 2*i+1, (struct rt_trie_node *) right); |
| } |
| } |
| |
| for (i = 0; i < olen; i++) { |
| struct tnode *inode; |
| struct rt_trie_node *node = tnode_get_child(oldtnode, i); |
| struct tnode *left, *right; |
| int size, j; |
| |
| /* An empty child */ |
| if (node == NULL) |
| continue; |
| |
| /* A leaf or an internal node with skipped bits */ |
| |
| if (IS_LEAF(node) || ((struct tnode *) node)->pos > |
| tn->pos + tn->bits - 1) { |
| if (tkey_extract_bits(node->key, |
| oldtnode->pos + oldtnode->bits, |
| 1) == 0) |
| put_child(tn, 2*i, node); |
| else |
| put_child(tn, 2*i+1, node); |
| continue; |
| } |
| |
| /* An internal node with two children */ |
| inode = (struct tnode *) node; |
| |
| if (inode->bits == 1) { |
| put_child(tn, 2*i, rtnl_dereference(inode->child[0])); |
| put_child(tn, 2*i+1, rtnl_dereference(inode->child[1])); |
| |
| tnode_free_safe(inode); |
| continue; |
| } |
| |
| /* An internal node with more than two children */ |
| |
| /* We will replace this node 'inode' with two new |
| * ones, 'left' and 'right', each with half of the |
| * original children. The two new nodes will have |
| * a position one bit further down the key and this |
| * means that the "significant" part of their keys |
| * (see the discussion near the top of this file) |
| * will differ by one bit, which will be "0" in |
| * left's key and "1" in right's key. Since we are |
| * moving the key position by one step, the bit that |
| * we are moving away from - the bit at position |
| * (inode->pos) - is the one that will differ between |
| * left and right. So... we synthesize that bit in the |
| * two new keys. |
| * The mask 'm' below will be a single "one" bit at |
| * the position (inode->pos) |
| */ |
| |
| /* Use the old key, but set the new significant |
| * bit to zero. |
| */ |
| |
| left = (struct tnode *) tnode_get_child(tn, 2*i); |
| put_child(tn, 2*i, NULL); |
| |
| BUG_ON(!left); |
| |
| right = (struct tnode *) tnode_get_child(tn, 2*i+1); |
| put_child(tn, 2*i+1, NULL); |
| |
| BUG_ON(!right); |
| |
| size = tnode_child_length(left); |
| for (j = 0; j < size; j++) { |
| put_child(left, j, rtnl_dereference(inode->child[j])); |
| put_child(right, j, rtnl_dereference(inode->child[j + size])); |
| } |
| put_child(tn, 2*i, resize(t, left)); |
| put_child(tn, 2*i+1, resize(t, right)); |
| |
| tnode_free_safe(inode); |
| } |
| tnode_free_safe(oldtnode); |
| return tn; |
| nomem: |
| tnode_clean_free(tn); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| static struct tnode *halve(struct trie *t, struct tnode *tn) |
| { |
| struct tnode *oldtnode = tn; |
| struct rt_trie_node *left, *right; |
| int i; |
| int olen = tnode_child_length(tn); |
| |
| pr_debug("In halve\n"); |
| |
| tn = tnode_new(oldtnode->key, oldtnode->pos, oldtnode->bits - 1); |
| |
| if (!tn) |
| return ERR_PTR(-ENOMEM); |
| |
| /* |
| * Preallocate and store tnodes before the actual work so we |
| * don't get into an inconsistent state if memory allocation |
| * fails. In case of failure we return the oldnode and halve |
| * of tnode is ignored. |
| */ |
| |
| for (i = 0; i < olen; i += 2) { |
| left = tnode_get_child(oldtnode, i); |
| right = tnode_get_child(oldtnode, i+1); |
| |
| /* Two nonempty children */ |
| if (left && right) { |
| struct tnode *newn; |
| |
| newn = tnode_new(left->key, tn->pos + tn->bits, 1); |
| |
| if (!newn) |
| goto nomem; |
| |
| put_child(tn, i/2, (struct rt_trie_node *)newn); |
| } |
| |
| } |
| |
| for (i = 0; i < olen; i += 2) { |
| struct tnode *newBinNode; |
| |
| left = tnode_get_child(oldtnode, i); |
| right = tnode_get_child(oldtnode, i+1); |
| |
| /* At least one of the children is empty */ |
| if (left == NULL) { |
| if (right == NULL) /* Both are empty */ |
| continue; |
| put_child(tn, i/2, right); |
| continue; |
| } |
| |
| if (right == NULL) { |
| put_child(tn, i/2, left); |
| continue; |
| } |
| |
| /* Two nonempty children */ |
| newBinNode = (struct tnode *) tnode_get_child(tn, i/2); |
| put_child(tn, i/2, NULL); |
| put_child(newBinNode, 0, left); |
| put_child(newBinNode, 1, right); |
| put_child(tn, i/2, resize(t, newBinNode)); |
| } |
| tnode_free_safe(oldtnode); |
| return tn; |
| nomem: |
| tnode_clean_free(tn); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| /* readside must use rcu_read_lock currently dump routines |
| via get_fa_head and dump */ |
| |
| static struct leaf_info *find_leaf_info(struct leaf *l, int plen) |
| { |
| struct hlist_head *head = &l->list; |
| struct hlist_node *node; |
| struct leaf_info *li; |
| |
| hlist_for_each_entry_rcu(li, node, head, hlist) |
| if (li->plen == plen) |
| return li; |
| |
| return NULL; |
| } |
| |
| static inline struct list_head *get_fa_head(struct leaf *l, int plen) |
| { |
| struct leaf_info *li = find_leaf_info(l, plen); |
| |
| if (!li) |
| return NULL; |
| |
| return &li->falh; |
| } |
| |
| static void insert_leaf_info(struct hlist_head *head, struct leaf_info *new) |
| { |
| struct leaf_info *li = NULL, *last = NULL; |
| struct hlist_node *node; |
| |
| if (hlist_empty(head)) { |
| hlist_add_head_rcu(&new->hlist, head); |
| } else { |
| hlist_for_each_entry(li, node, head, hlist) { |
| if (new->plen > li->plen) |
| break; |
| |
| last = li; |
| } |
| if (last) |
| hlist_add_after_rcu(&last->hlist, &new->hlist); |
| else |
| hlist_add_before_rcu(&new->hlist, &li->hlist); |
| } |
| } |
| |
| /* rcu_read_lock needs to be hold by caller from readside */ |
| |
| static struct leaf * |
| fib_find_node(struct trie *t, u32 key) |
| { |
| int pos; |
| struct tnode *tn; |
| struct rt_trie_node *n; |
| |
| pos = 0; |
| n = rcu_dereference_rtnl(t->trie); |
| |
| while (n != NULL && NODE_TYPE(n) == T_TNODE) { |
| tn = (struct tnode *) n; |
| |
| check_tnode(tn); |
| |
| if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { |
| pos = tn->pos + tn->bits; |
| n = tnode_get_child_rcu(tn, |
| tkey_extract_bits(key, |
| tn->pos, |
| tn->bits)); |
| } else |
| break; |
| } |
| /* Case we have found a leaf. Compare prefixes */ |
| |
| if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) |
| return (struct leaf *)n; |
| |
| return NULL; |
| } |
| |
| static void trie_rebalance(struct trie *t, struct tnode *tn) |
| { |
| int wasfull; |
| t_key cindex, key; |
| struct tnode *tp; |
| |
| key = tn->key; |
| |
| while (tn != NULL && (tp = node_parent((struct rt_trie_node *)tn)) != NULL) { |
| cindex = tkey_extract_bits(key, tp->pos, tp->bits); |
| wasfull = tnode_full(tp, tnode_get_child(tp, cindex)); |
| tn = (struct tnode *)resize(t, tn); |
| |
| tnode_put_child_reorg(tp, cindex, |
| (struct rt_trie_node *)tn, wasfull); |
| |
| tp = node_parent((struct rt_trie_node *) tn); |
| if (!tp) |
| rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); |
| |
| tnode_free_flush(); |
| if (!tp) |
| break; |
| tn = tp; |
| } |
| |
| /* Handle last (top) tnode */ |
| if (IS_TNODE(tn)) |
| tn = (struct tnode *)resize(t, tn); |
| |
| rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); |
| tnode_free_flush(); |
| } |
| |
| /* only used from updater-side */ |
| |
| static struct list_head *fib_insert_node(struct trie *t, u32 key, int plen) |
| { |
| int pos, newpos; |
| struct tnode *tp = NULL, *tn = NULL; |
| struct rt_trie_node *n; |
| struct leaf *l; |
| int missbit; |
| struct list_head *fa_head = NULL; |
| struct leaf_info *li; |
| t_key cindex; |
| |
| pos = 0; |
| n = rtnl_dereference(t->trie); |
| |
| /* If we point to NULL, stop. Either the tree is empty and we should |
| * just put a new leaf in if, or we have reached an empty child slot, |
| * and we should just put our new leaf in that. |
| * If we point to a T_TNODE, check if it matches our key. Note that |
| * a T_TNODE might be skipping any number of bits - its 'pos' need |
| * not be the parent's 'pos'+'bits'! |
| * |
| * If it does match the current key, get pos/bits from it, extract |
| * the index from our key, push the T_TNODE and walk the tree. |
| * |
| * If it doesn't, we have to replace it with a new T_TNODE. |
| * |
| * If we point to a T_LEAF, it might or might not have the same key |
| * as we do. If it does, just change the value, update the T_LEAF's |
| * value, and return it. |
| * If it doesn't, we need to replace it with a T_TNODE. |
| */ |
| |
| while (n != NULL && NODE_TYPE(n) == T_TNODE) { |
| tn = (struct tnode *) n; |
| |
| check_tnode(tn); |
| |
| if (tkey_sub_equals(tn->key, pos, tn->pos-pos, key)) { |
| tp = tn; |
| pos = tn->pos + tn->bits; |
| n = tnode_get_child(tn, |
| tkey_extract_bits(key, |
| tn->pos, |
| tn->bits)); |
| |
| BUG_ON(n && node_parent(n) != tn); |
| } else |
| break; |
| } |
| |
| /* |
| * n ----> NULL, LEAF or TNODE |
| * |
| * tp is n's (parent) ----> NULL or TNODE |
| */ |
| |
| BUG_ON(tp && IS_LEAF(tp)); |
| |
| /* Case 1: n is a leaf. Compare prefixes */ |
| |
| if (n != NULL && IS_LEAF(n) && tkey_equals(key, n->key)) { |
| l = (struct leaf *) n; |
| li = leaf_info_new(plen); |
| |
| if (!li) |
| return NULL; |
| |
| fa_head = &li->falh; |
| insert_leaf_info(&l->list, li); |
| goto done; |
| } |
| l = leaf_new(); |
| |
| if (!l) |
| return NULL; |
| |
| l->key = key; |
| li = leaf_info_new(plen); |
| |
| if (!li) { |
| free_leaf(l); |
| return NULL; |
| } |
| |
| fa_head = &li->falh; |
| insert_leaf_info(&l->list, li); |
| |
| if (t->trie && n == NULL) { |
| /* Case 2: n is NULL, and will just insert a new leaf */ |
| |
| node_set_parent((struct rt_trie_node *)l, tp); |
| |
| cindex = tkey_extract_bits(key, tp->pos, tp->bits); |
| put_child(tp, cindex, (struct rt_trie_node *)l); |
| } else { |
| /* Case 3: n is a LEAF or a TNODE and the key doesn't match. */ |
| /* |
| * Add a new tnode here |
| * first tnode need some special handling |
| */ |
| |
| if (tp) |
| pos = tp->pos+tp->bits; |
| else |
| pos = 0; |
| |
| if (n) { |
| newpos = tkey_mismatch(key, pos, n->key); |
| tn = tnode_new(n->key, newpos, 1); |
| } else { |
| newpos = 0; |
| tn = tnode_new(key, newpos, 1); /* First tnode */ |
| } |
| |
| if (!tn) { |
| free_leaf_info(li); |
| free_leaf(l); |
| return NULL; |
| } |
| |
| node_set_parent((struct rt_trie_node *)tn, tp); |
| |
| missbit = tkey_extract_bits(key, newpos, 1); |
| put_child(tn, missbit, (struct rt_trie_node *)l); |
| put_child(tn, 1-missbit, n); |
| |
| if (tp) { |
| cindex = tkey_extract_bits(key, tp->pos, tp->bits); |
| put_child(tp, cindex, (struct rt_trie_node *)tn); |
| } else { |
| rcu_assign_pointer(t->trie, (struct rt_trie_node *)tn); |
| tp = tn; |
| } |
| } |
| |
| if (tp && tp->pos + tp->bits > 32) |
| pr_warn("fib_trie tp=%p pos=%d, bits=%d, key=%0x plen=%d\n", |
| tp, tp->pos, tp->bits, key, plen); |
| |
| /* Rebalance the trie */ |
| |
| trie_rebalance(t, tp); |
| done: |
| return fa_head; |
| } |
| |
| /* |
| * Caller must hold RTNL. |
| */ |
| int fib_table_insert(struct fib_table *tb, struct fib_config *cfg) |
| { |
| struct trie *t = (struct trie *) tb->tb_data; |
| struct fib_alias *fa, *new_fa; |
| struct list_head *fa_head = NULL; |
| struct fib_info *fi; |
| int plen = cfg->fc_dst_len; |
| u8 tos = cfg->fc_tos; |
| u32 key, mask; |
| int err; |
| struct leaf *l; |
| |
| if (plen > 32) |
| return -EINVAL; |
| |
| key = ntohl(cfg->fc_dst); |
| |
| pr_debug("Insert table=%u %08x/%d\n", tb->tb_id, key, plen); |
| |
| mask = ntohl(inet_make_mask(plen)); |
| |
| if (key & ~mask) |
| return -EINVAL; |
| |
| key = key & mask; |
| |
| fi = fib_create_info(cfg); |
| if (IS_ERR(fi)) { |
| err = PTR_ERR(fi); |
| goto err; |
| } |
| |
| l = fib_find_node(t, key); |
| fa = NULL; |
| |
| if (l) { |
| fa_head = get_fa_head(l, plen); |
| fa = fib_find_alias(fa_head, tos, fi->fib_priority); |
| } |
| |
| /* Now fa, if non-NULL, points to the first fib alias |
| * with the same keys [prefix,tos,priority], if such key already |
| * exists or to the node before which we will insert new one. |
| * |
| * If fa is NULL, we will need to allocate a new one and |
| * insert to the head of f. |
| * |
| * If f is NULL, no fib node matched the destination key |
| * and we need to allocate a new one of those as well. |
| */ |
| |
| if (fa && fa->fa_tos == tos && |
| fa->fa_info->fib_priority == fi->fib_priority) { |
| struct fib_alias *fa_first, *fa_match; |
| |
| err = -EEXIST; |
| if (cfg->fc_nlflags & NLM_F_EXCL) |
| goto out; |
| |
| /* We have 2 goals: |
| * 1. Find exact match for type, scope, fib_info to avoid |
| * duplicate routes |
| * 2. Find next 'fa' (or head), NLM_F_APPEND inserts before it |
| */ |
| fa_match = NULL; |
| fa_first = fa; |
| fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list); |
| list_for_each_entry_continue(fa, fa_head, fa_list) { |
| if (fa->fa_tos != tos) |
| break; |
| if (fa->fa_info->fib_priority != fi->fib_priority) |
| break; |
| if (fa->fa_type == cfg->fc_type && |
| fa->fa_info == fi) { |
| fa_match = fa; |
| break; |
| } |
| } |
| |
| if (cfg->fc_nlflags & NLM_F_REPLACE) { |
| struct fib_info *fi_drop; |
| u8 state; |
| |
| fa = fa_first; |
| if (fa_match) { |
| if (fa == fa_match) |
| err = 0; |
| goto out; |
| } |
| err = -ENOBUFS; |
| new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL); |
| if (new_fa == NULL) |
| goto out; |
| |
| fi_drop = fa->fa_info; |
| new_fa->fa_tos = fa->fa_tos; |
| new_fa->fa_info = fi; |
| new_fa->fa_type = cfg->fc_type; |
| state = fa->fa_state; |
| new_fa->fa_state = state & ~FA_S_ACCESSED; |
| |
| list_replace_rcu(&fa->fa_list, &new_fa->fa_list); |
| alias_free_mem_rcu(fa); |
| |
| fib_release_info(fi_drop); |
| if (state & FA_S_ACCESSED) |
| rt_cache_flush(cfg->fc_nlinfo.nl_net, -1); |
| rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, |
| tb->tb_id, &cfg->fc_nlinfo, NLM_F_REPLACE); |
| |
| goto succeeded; |
| } |
| /* Error if we find a perfect match which |
| * uses the same scope, type, and nexthop |
| * information. |
| */ |
| if (fa_match) |
| goto out; |
| |
| if (!(cfg->fc_nlflags & NLM_F_APPEND)) |
| fa = fa_first; |
| } |
| err = -ENOENT; |
| if (!(cfg->fc_nlflags & NLM_F_CREATE)) |
| goto out; |
| |
| err = -ENOBUFS; |
| new_fa = kmem_cache_alloc(fn_alias_kmem, GFP_KERNEL); |
| if (new_fa == NULL) |
| goto out; |
| |
| new_fa->fa_info = fi; |
| new_fa->fa_tos = tos; |
| new_fa->fa_type = cfg->fc_type; |
| new_fa->fa_state = 0; |
| /* |
| * Insert new entry to the list. |
| */ |
| |
| if (!fa_head) { |
| fa_head = fib_insert_node(t, key, plen); |
| if (unlikely(!fa_head)) { |
| err = -ENOMEM; |
| goto out_free_new_fa; |
| } |
| } |
| |
| if (!plen) |
| tb->tb_num_default++; |
| |
| list_add_tail_rcu(&new_fa->fa_list, |
| (fa ? &fa->fa_list : fa_head)); |
| |
| rt_cache_flush(cfg->fc_nlinfo.nl_net, -1); |
| rtmsg_fib(RTM_NEWROUTE, htonl(key), new_fa, plen, tb->tb_id, |
| &cfg->fc_nlinfo, 0); |
| succeeded: |
| return 0; |
| |
| out_free_new_fa: |
| kmem_cache_free(fn_alias_kmem, new_fa); |
| out: |
| fib_release_info(fi); |
| err: |
| return err; |
| } |
| |
| /* should be called with rcu_read_lock */ |
| static int check_leaf(struct fib_table *tb, struct trie *t, struct leaf *l, |
| t_key key, const struct flowi4 *flp, |
| struct fib_result *res, int fib_flags) |
| { |
| struct leaf_info *li; |
| struct hlist_head *hhead = &l->list; |
| struct hlist_node *node; |
| |
| hlist_for_each_entry_rcu(li, node, hhead, hlist) { |
| struct fib_alias *fa; |
| |
| if (l->key != (key & li->mask_plen)) |
| continue; |
| |
| list_for_each_entry_rcu(fa, &li->falh, fa_list) { |
| struct fib_info *fi = fa->fa_info; |
| int nhsel, err; |
| |
| if (fa->fa_tos && fa->fa_tos != flp->flowi4_tos) |
| continue; |
| if (fi->fib_dead) |
| continue; |
| if (fa->fa_info->fib_scope < flp->flowi4_scope) |
| continue; |
| fib_alias_accessed(fa); |
| err = fib_props[fa->fa_type].error; |
| if (err) { |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.semantic_match_passed++; |
| #endif |
| return err; |
| } |
| if (fi->fib_flags & RTNH_F_DEAD) |
| continue; |
| for (nhsel = 0; nhsel < fi->fib_nhs; nhsel++) { |
| const struct fib_nh *nh = &fi->fib_nh[nhsel]; |
| |
| if (nh->nh_flags & RTNH_F_DEAD) |
| continue; |
| if (flp->flowi4_oif && flp->flowi4_oif != nh->nh_oif) |
| continue; |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.semantic_match_passed++; |
| #endif |
| res->prefixlen = li->plen; |
| res->nh_sel = nhsel; |
| res->type = fa->fa_type; |
| res->scope = fa->fa_info->fib_scope; |
| res->fi = fi; |
| res->table = tb; |
| res->fa_head = &li->falh; |
| if (!(fib_flags & FIB_LOOKUP_NOREF)) |
| atomic_inc(&fi->fib_clntref); |
| return 0; |
| } |
| } |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.semantic_match_miss++; |
| #endif |
| } |
| |
| return 1; |
| } |
| |
| int fib_table_lookup(struct fib_table *tb, const struct flowi4 *flp, |
| struct fib_result *res, int fib_flags) |
| { |
| struct trie *t = (struct trie *) tb->tb_data; |
| int ret; |
| struct rt_trie_node *n; |
| struct tnode *pn; |
| unsigned int pos, bits; |
| t_key key = ntohl(flp->daddr); |
| unsigned int chopped_off; |
| t_key cindex = 0; |
| unsigned int current_prefix_length = KEYLENGTH; |
| struct tnode *cn; |
| t_key pref_mismatch; |
| |
| rcu_read_lock(); |
| |
| n = rcu_dereference(t->trie); |
| if (!n) |
| goto failed; |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.gets++; |
| #endif |
| |
| /* Just a leaf? */ |
| if (IS_LEAF(n)) { |
| ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags); |
| goto found; |
| } |
| |
| pn = (struct tnode *) n; |
| chopped_off = 0; |
| |
| while (pn) { |
| pos = pn->pos; |
| bits = pn->bits; |
| |
| if (!chopped_off) |
| cindex = tkey_extract_bits(mask_pfx(key, current_prefix_length), |
| pos, bits); |
| |
| n = tnode_get_child_rcu(pn, cindex); |
| |
| if (n == NULL) { |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.null_node_hit++; |
| #endif |
| goto backtrace; |
| } |
| |
| if (IS_LEAF(n)) { |
| ret = check_leaf(tb, t, (struct leaf *)n, key, flp, res, fib_flags); |
| if (ret > 0) |
| goto backtrace; |
| goto found; |
| } |
| |
| cn = (struct tnode *)n; |
| |
| /* |
| * It's a tnode, and we can do some extra checks here if we |
| * like, to avoid descending into a dead-end branch. |
| * This tnode is in the parent's child array at index |
| * key[p_pos..p_pos+p_bits] but potentially with some bits |
| * chopped off, so in reality the index may be just a |
| * subprefix, padded with zero at the end. |
| * We can also take a look at any skipped bits in this |
| * tnode - everything up to p_pos is supposed to be ok, |
| * and the non-chopped bits of the index (se previous |
| * paragraph) are also guaranteed ok, but the rest is |
| * considered unknown. |
| * |
| * The skipped bits are key[pos+bits..cn->pos]. |
| */ |
| |
| /* If current_prefix_length < pos+bits, we are already doing |
| * actual prefix matching, which means everything from |
| * pos+(bits-chopped_off) onward must be zero along some |
| * branch of this subtree - otherwise there is *no* valid |
| * prefix present. Here we can only check the skipped |
| * bits. Remember, since we have already indexed into the |
| * parent's child array, we know that the bits we chopped of |
| * *are* zero. |
| */ |
| |
| /* NOTA BENE: Checking only skipped bits |
| for the new node here */ |
| |
| if (current_prefix_length < pos+bits) { |
| if (tkey_extract_bits(cn->key, current_prefix_length, |
| cn->pos - current_prefix_length) |
| || !(cn->child[0])) |
| goto backtrace; |
| } |
| |
| /* |
| * If chopped_off=0, the index is fully validated and we |
| * only need to look at the skipped bits for this, the new, |
| * tnode. What we actually want to do is to find out if |
| * these skipped bits match our key perfectly, or if we will |
| * have to count on finding a matching prefix further down, |
| * because if we do, we would like to have some way of |
| * verifying the existence of such a prefix at this point. |
| */ |
| |
| /* The only thing we can do at this point is to verify that |
| * any such matching prefix can indeed be a prefix to our |
| * key, and if the bits in the node we are inspecting that |
| * do not match our key are not ZERO, this cannot be true. |
| * Thus, find out where there is a mismatch (before cn->pos) |
| * and verify that all the mismatching bits are zero in the |
| * new tnode's key. |
| */ |
| |
| /* |
| * Note: We aren't very concerned about the piece of |
| * the key that precede pn->pos+pn->bits, since these |
| * have already been checked. The bits after cn->pos |
| * aren't checked since these are by definition |
| * "unknown" at this point. Thus, what we want to see |
| * is if we are about to enter the "prefix matching" |
| * state, and in that case verify that the skipped |
| * bits that will prevail throughout this subtree are |
| * zero, as they have to be if we are to find a |
| * matching prefix. |
| */ |
| |
| pref_mismatch = mask_pfx(cn->key ^ key, cn->pos); |
| |
| /* |
| * In short: If skipped bits in this node do not match |
| * the search key, enter the "prefix matching" |
| * state.directly. |
| */ |
| if (pref_mismatch) { |
| /* fls(x) = __fls(x) + 1 */ |
| int mp = KEYLENGTH - __fls(pref_mismatch) - 1; |
| |
| if (tkey_extract_bits(cn->key, mp, cn->pos - mp) != 0) |
| goto backtrace; |
| |
| if (current_prefix_length >= cn->pos) |
| current_prefix_length = mp; |
| } |
| |
| pn = (struct tnode *)n; /* Descend */ |
| chopped_off = 0; |
| continue; |
| |
| backtrace: |
| chopped_off++; |
| |
| /* As zero don't change the child key (cindex) */ |
| while ((chopped_off <= pn->bits) |
| && !(cindex & (1<<(chopped_off-1)))) |
| chopped_off++; |
| |
| /* Decrease current_... with bits chopped off */ |
| if (current_prefix_length > pn->pos + pn->bits - chopped_off) |
| current_prefix_length = pn->pos + pn->bits |
| - chopped_off; |
| |
| /* |
| * Either we do the actual chop off according or if we have |
| * chopped off all bits in this tnode walk up to our parent. |
| */ |
| |
| if (chopped_off <= pn->bits) { |
| cindex &= ~(1 << (chopped_off-1)); |
| } else { |
| struct tnode *parent = node_parent_rcu((struct rt_trie_node *) pn); |
| if (!parent) |
| goto failed; |
| |
| /* Get Child's index */ |
| cindex = tkey_extract_bits(pn->key, parent->pos, parent->bits); |
| pn = parent; |
| chopped_off = 0; |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| t->stats.backtrack++; |
| #endif |
| goto backtrace; |
| } |
| } |
| failed: |
| ret = 1; |
| found: |
| rcu_read_unlock(); |
| return ret; |
| } |
| EXPORT_SYMBOL_GPL(fib_table_lookup); |
| |
| /* |
| * Remove the leaf and return parent. |
| */ |
| static void trie_leaf_remove(struct trie *t, struct leaf *l) |
| { |
| struct tnode *tp = node_parent((struct rt_trie_node *) l); |
| |
| pr_debug("entering trie_leaf_remove(%p)\n", l); |
| |
| if (tp) { |
| t_key cindex = tkey_extract_bits(l->key, tp->pos, tp->bits); |
| put_child(tp, cindex, NULL); |
| trie_rebalance(t, tp); |
| } else |
| RCU_INIT_POINTER(t->trie, NULL); |
| |
| free_leaf(l); |
| } |
| |
| /* |
| * Caller must hold RTNL. |
| */ |
| int fib_table_delete(struct fib_table *tb, struct fib_config *cfg) |
| { |
| struct trie *t = (struct trie *) tb->tb_data; |
| u32 key, mask; |
| int plen = cfg->fc_dst_len; |
| u8 tos = cfg->fc_tos; |
| struct fib_alias *fa, *fa_to_delete; |
| struct list_head *fa_head; |
| struct leaf *l; |
| struct leaf_info *li; |
| |
| if (plen > 32) |
| return -EINVAL; |
| |
| key = ntohl(cfg->fc_dst); |
| mask = ntohl(inet_make_mask(plen)); |
| |
| if (key & ~mask) |
| return -EINVAL; |
| |
| key = key & mask; |
| l = fib_find_node(t, key); |
| |
| if (!l) |
| return -ESRCH; |
| |
| li = find_leaf_info(l, plen); |
| |
| if (!li) |
| return -ESRCH; |
| |
| fa_head = &li->falh; |
| fa = fib_find_alias(fa_head, tos, 0); |
| |
| if (!fa) |
| return -ESRCH; |
| |
| pr_debug("Deleting %08x/%d tos=%d t=%p\n", key, plen, tos, t); |
| |
| fa_to_delete = NULL; |
| fa = list_entry(fa->fa_list.prev, struct fib_alias, fa_list); |
| list_for_each_entry_continue(fa, fa_head, fa_list) { |
| struct fib_info *fi = fa->fa_info; |
| |
| if (fa->fa_tos != tos) |
| break; |
| |
| if ((!cfg->fc_type || fa->fa_type == cfg->fc_type) && |
| (cfg->fc_scope == RT_SCOPE_NOWHERE || |
| fa->fa_info->fib_scope == cfg->fc_scope) && |
| (!cfg->fc_prefsrc || |
| fi->fib_prefsrc == cfg->fc_prefsrc) && |
| (!cfg->fc_protocol || |
| fi->fib_protocol == cfg->fc_protocol) && |
| fib_nh_match(cfg, fi) == 0) { |
| fa_to_delete = fa; |
| break; |
| } |
| } |
| |
| if (!fa_to_delete) |
| return -ESRCH; |
| |
| fa = fa_to_delete; |
| rtmsg_fib(RTM_DELROUTE, htonl(key), fa, plen, tb->tb_id, |
| &cfg->fc_nlinfo, 0); |
| |
| list_del_rcu(&fa->fa_list); |
| |
| if (!plen) |
| tb->tb_num_default--; |
| |
| if (list_empty(fa_head)) { |
| hlist_del_rcu(&li->hlist); |
| free_leaf_info(li); |
| } |
| |
| if (hlist_empty(&l->list)) |
| trie_leaf_remove(t, l); |
| |
| if (fa->fa_state & FA_S_ACCESSED) |
| rt_cache_flush(cfg->fc_nlinfo.nl_net, -1); |
| |
| fib_release_info(fa->fa_info); |
| alias_free_mem_rcu(fa); |
| return 0; |
| } |
| |
| static int trie_flush_list(struct list_head *head) |
| { |
| struct fib_alias *fa, *fa_node; |
| int found = 0; |
| |
| list_for_each_entry_safe(fa, fa_node, head, fa_list) { |
| struct fib_info *fi = fa->fa_info; |
| |
| if (fi && (fi->fib_flags & RTNH_F_DEAD)) { |
| list_del_rcu(&fa->fa_list); |
| fib_release_info(fa->fa_info); |
| alias_free_mem_rcu(fa); |
| found++; |
| } |
| } |
| return found; |
| } |
| |
| static int trie_flush_leaf(struct leaf *l) |
| { |
| int found = 0; |
| struct hlist_head *lih = &l->list; |
| struct hlist_node *node, *tmp; |
| struct leaf_info *li = NULL; |
| |
| hlist_for_each_entry_safe(li, node, tmp, lih, hlist) { |
| found += trie_flush_list(&li->falh); |
| |
| if (list_empty(&li->falh)) { |
| hlist_del_rcu(&li->hlist); |
| free_leaf_info(li); |
| } |
| } |
| return found; |
| } |
| |
| /* |
| * Scan for the next right leaf starting at node p->child[idx] |
| * Since we have back pointer, no recursion necessary. |
| */ |
| static struct leaf *leaf_walk_rcu(struct tnode *p, struct rt_trie_node *c) |
| { |
| do { |
| t_key idx; |
| |
| if (c) |
| idx = tkey_extract_bits(c->key, p->pos, p->bits) + 1; |
| else |
| idx = 0; |
| |
| while (idx < 1u << p->bits) { |
| c = tnode_get_child_rcu(p, idx++); |
| if (!c) |
| continue; |
| |
| if (IS_LEAF(c)) { |
| prefetch(rcu_dereference_rtnl(p->child[idx])); |
| return (struct leaf *) c; |
| } |
| |
| /* Rescan start scanning in new node */ |
| p = (struct tnode *) c; |
| idx = 0; |
| } |
| |
| /* Node empty, walk back up to parent */ |
| c = (struct rt_trie_node *) p; |
| } while ((p = node_parent_rcu(c)) != NULL); |
| |
| return NULL; /* Root of trie */ |
| } |
| |
| static struct leaf *trie_firstleaf(struct trie *t) |
| { |
| struct tnode *n = (struct tnode *)rcu_dereference_rtnl(t->trie); |
| |
| if (!n) |
| return NULL; |
| |
| if (IS_LEAF(n)) /* trie is just a leaf */ |
| return (struct leaf *) n; |
| |
| return leaf_walk_rcu(n, NULL); |
| } |
| |
| static struct leaf *trie_nextleaf(struct leaf *l) |
| { |
| struct rt_trie_node *c = (struct rt_trie_node *) l; |
| struct tnode *p = node_parent_rcu(c); |
| |
| if (!p) |
| return NULL; /* trie with just one leaf */ |
| |
| return leaf_walk_rcu(p, c); |
| } |
| |
| static struct leaf *trie_leafindex(struct trie *t, int index) |
| { |
| struct leaf *l = trie_firstleaf(t); |
| |
| while (l && index-- > 0) |
| l = trie_nextleaf(l); |
| |
| return l; |
| } |
| |
| |
| /* |
| * Caller must hold RTNL. |
| */ |
| int fib_table_flush(struct fib_table *tb) |
| { |
| struct trie *t = (struct trie *) tb->tb_data; |
| struct leaf *l, *ll = NULL; |
| int found = 0; |
| |
| for (l = trie_firstleaf(t); l; l = trie_nextleaf(l)) { |
| found += trie_flush_leaf(l); |
| |
| if (ll && hlist_empty(&ll->list)) |
| trie_leaf_remove(t, ll); |
| ll = l; |
| } |
| |
| if (ll && hlist_empty(&ll->list)) |
| trie_leaf_remove(t, ll); |
| |
| pr_debug("trie_flush found=%d\n", found); |
| return found; |
| } |
| |
| void fib_free_table(struct fib_table *tb) |
| { |
| kfree(tb); |
| } |
| |
| static int fn_trie_dump_fa(t_key key, int plen, struct list_head *fah, |
| struct fib_table *tb, |
| struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| int i, s_i; |
| struct fib_alias *fa; |
| __be32 xkey = htonl(key); |
| |
| s_i = cb->args[5]; |
| i = 0; |
| |
| /* rcu_read_lock is hold by caller */ |
| |
| list_for_each_entry_rcu(fa, fah, fa_list) { |
| if (i < s_i) { |
| i++; |
| continue; |
| } |
| |
| if (fib_dump_info(skb, NETLINK_CB(cb->skb).pid, |
| cb->nlh->nlmsg_seq, |
| RTM_NEWROUTE, |
| tb->tb_id, |
| fa->fa_type, |
| xkey, |
| plen, |
| fa->fa_tos, |
| fa->fa_info, NLM_F_MULTI) < 0) { |
| cb->args[5] = i; |
| return -1; |
| } |
| i++; |
| } |
| cb->args[5] = i; |
| return skb->len; |
| } |
| |
| static int fn_trie_dump_leaf(struct leaf *l, struct fib_table *tb, |
| struct sk_buff *skb, struct netlink_callback *cb) |
| { |
| struct leaf_info *li; |
| struct hlist_node *node; |
| int i, s_i; |
| |
| s_i = cb->args[4]; |
| i = 0; |
| |
| /* rcu_read_lock is hold by caller */ |
| hlist_for_each_entry_rcu(li, node, &l->list, hlist) { |
| if (i < s_i) { |
| i++; |
| continue; |
| } |
| |
| if (i > s_i) |
| cb->args[5] = 0; |
| |
| if (list_empty(&li->falh)) |
| continue; |
| |
| if (fn_trie_dump_fa(l->key, li->plen, &li->falh, tb, skb, cb) < 0) { |
| cb->args[4] = i; |
| return -1; |
| } |
| i++; |
| } |
| |
| cb->args[4] = i; |
| return skb->len; |
| } |
| |
| int fib_table_dump(struct fib_table *tb, struct sk_buff *skb, |
| struct netlink_callback *cb) |
| { |
| struct leaf *l; |
| struct trie *t = (struct trie *) tb->tb_data; |
| t_key key = cb->args[2]; |
| int count = cb->args[3]; |
| |
| rcu_read_lock(); |
| /* Dump starting at last key. |
| * Note: 0.0.0.0/0 (ie default) is first key. |
| */ |
| if (count == 0) |
| l = trie_firstleaf(t); |
| else { |
| /* Normally, continue from last key, but if that is missing |
| * fallback to using slow rescan |
| */ |
| l = fib_find_node(t, key); |
| if (!l) |
| l = trie_leafindex(t, count); |
| } |
| |
| while (l) { |
| cb->args[2] = l->key; |
| if (fn_trie_dump_leaf(l, tb, skb, cb) < 0) { |
| cb->args[3] = count; |
| rcu_read_unlock(); |
| return -1; |
| } |
| |
| ++count; |
| l = trie_nextleaf(l); |
| memset(&cb->args[4], 0, |
| sizeof(cb->args) - 4*sizeof(cb->args[0])); |
| } |
| cb->args[3] = count; |
| rcu_read_unlock(); |
| |
| return skb->len; |
| } |
| |
| void __init fib_trie_init(void) |
| { |
| fn_alias_kmem = kmem_cache_create("ip_fib_alias", |
| sizeof(struct fib_alias), |
| 0, SLAB_PANIC, NULL); |
| |
| trie_leaf_kmem = kmem_cache_create("ip_fib_trie", |
| max(sizeof(struct leaf), |
| sizeof(struct leaf_info)), |
| 0, SLAB_PANIC, NULL); |
| } |
| |
| |
| struct fib_table *fib_trie_table(u32 id) |
| { |
| struct fib_table *tb; |
| struct trie *t; |
| |
| tb = kmalloc(sizeof(struct fib_table) + sizeof(struct trie), |
| GFP_KERNEL); |
| if (tb == NULL) |
| return NULL; |
| |
| tb->tb_id = id; |
| tb->tb_default = -1; |
| tb->tb_num_default = 0; |
| |
| t = (struct trie *) tb->tb_data; |
| memset(t, 0, sizeof(*t)); |
| |
| return tb; |
| } |
| |
| #ifdef CONFIG_PROC_FS |
| /* Depth first Trie walk iterator */ |
| struct fib_trie_iter { |
| struct seq_net_private p; |
| struct fib_table *tb; |
| struct tnode *tnode; |
| unsigned int index; |
| unsigned int depth; |
| }; |
| |
| static struct rt_trie_node *fib_trie_get_next(struct fib_trie_iter *iter) |
| { |
| struct tnode *tn = iter->tnode; |
| unsigned int cindex = iter->index; |
| struct tnode *p; |
| |
| /* A single entry routing table */ |
| if (!tn) |
| return NULL; |
| |
| pr_debug("get_next iter={node=%p index=%d depth=%d}\n", |
| iter->tnode, iter->index, iter->depth); |
| rescan: |
| while (cindex < (1<<tn->bits)) { |
| struct rt_trie_node *n = tnode_get_child_rcu(tn, cindex); |
| |
| if (n) { |
| if (IS_LEAF(n)) { |
| iter->tnode = tn; |
| iter->index = cindex + 1; |
| } else { |
| /* push down one level */ |
| iter->tnode = (struct tnode *) n; |
| iter->index = 0; |
| ++iter->depth; |
| } |
| return n; |
| } |
| |
| ++cindex; |
| } |
| |
| /* Current node exhausted, pop back up */ |
| p = node_parent_rcu((struct rt_trie_node *)tn); |
| if (p) { |
| cindex = tkey_extract_bits(tn->key, p->pos, p->bits)+1; |
| tn = p; |
| --iter->depth; |
| goto rescan; |
| } |
| |
| /* got root? */ |
| return NULL; |
| } |
| |
| static struct rt_trie_node *fib_trie_get_first(struct fib_trie_iter *iter, |
| struct trie *t) |
| { |
| struct rt_trie_node *n; |
| |
| if (!t) |
| return NULL; |
| |
| n = rcu_dereference(t->trie); |
| if (!n) |
| return NULL; |
| |
| if (IS_TNODE(n)) { |
| iter->tnode = (struct tnode *) n; |
| iter->index = 0; |
| iter->depth = 1; |
| } else { |
| iter->tnode = NULL; |
| iter->index = 0; |
| iter->depth = 0; |
| } |
| |
| return n; |
| } |
| |
| static void trie_collect_stats(struct trie *t, struct trie_stat *s) |
| { |
| struct rt_trie_node *n; |
| struct fib_trie_iter iter; |
| |
| memset(s, 0, sizeof(*s)); |
| |
| rcu_read_lock(); |
| for (n = fib_trie_get_first(&iter, t); n; n = fib_trie_get_next(&iter)) { |
| if (IS_LEAF(n)) { |
| struct leaf *l = (struct leaf *)n; |
| struct leaf_info *li; |
| struct hlist_node *tmp; |
| |
| s->leaves++; |
| s->totdepth += iter.depth; |
| if (iter.depth > s->maxdepth) |
| s->maxdepth = iter.depth; |
| |
| hlist_for_each_entry_rcu(li, tmp, &l->list, hlist) |
| ++s->prefixes; |
| } else { |
| const struct tnode *tn = (const struct tnode *) n; |
| int i; |
| |
| s->tnodes++; |
| if (tn->bits < MAX_STAT_DEPTH) |
| s->nodesizes[tn->bits]++; |
| |
| for (i = 0; i < (1<<tn->bits); i++) |
| if (!tn->child[i]) |
| s->nullpointers++; |
| } |
| } |
| rcu_read_unlock(); |
| } |
| |
| /* |
| * This outputs /proc/net/fib_triestats |
| */ |
| static void trie_show_stats(struct seq_file *seq, struct trie_stat *stat) |
| { |
| unsigned int i, max, pointers, bytes, avdepth; |
| |
| if (stat->leaves) |
| avdepth = stat->totdepth*100 / stat->leaves; |
| else |
| avdepth = 0; |
| |
| seq_printf(seq, "\tAver depth: %u.%02d\n", |
| avdepth / 100, avdepth % 100); |
| seq_printf(seq, "\tMax depth: %u\n", stat->maxdepth); |
| |
| seq_printf(seq, "\tLeaves: %u\n", stat->leaves); |
| bytes = sizeof(struct leaf) * stat->leaves; |
| |
| seq_printf(seq, "\tPrefixes: %u\n", stat->prefixes); |
| bytes += sizeof(struct leaf_info) * stat->prefixes; |
| |
| seq_printf(seq, "\tInternal nodes: %u\n\t", stat->tnodes); |
| bytes += sizeof(struct tnode) * stat->tnodes; |
| |
| max = MAX_STAT_DEPTH; |
| while (max > 0 && stat->nodesizes[max-1] == 0) |
| max--; |
| |
| pointers = 0; |
| for (i = 1; i <= max; i++) |
| if (stat->nodesizes[i] != 0) { |
| seq_printf(seq, " %u: %u", i, stat->nodesizes[i]); |
| pointers += (1<<i) * stat->nodesizes[i]; |
| } |
| seq_putc(seq, '\n'); |
| seq_printf(seq, "\tPointers: %u\n", pointers); |
| |
| bytes += sizeof(struct rt_trie_node *) * pointers; |
| seq_printf(seq, "Null ptrs: %u\n", stat->nullpointers); |
| seq_printf(seq, "Total size: %u kB\n", (bytes + 1023) / 1024); |
| } |
| |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| static void trie_show_usage(struct seq_file *seq, |
| const struct trie_use_stats *stats) |
| { |
| seq_printf(seq, "\nCounters:\n---------\n"); |
| seq_printf(seq, "gets = %u\n", stats->gets); |
| seq_printf(seq, "backtracks = %u\n", stats->backtrack); |
| seq_printf(seq, "semantic match passed = %u\n", |
| stats->semantic_match_passed); |
| seq_printf(seq, "semantic match miss = %u\n", |
| stats->semantic_match_miss); |
| seq_printf(seq, "null node hit= %u\n", stats->null_node_hit); |
| seq_printf(seq, "skipped node resize = %u\n\n", |
| stats->resize_node_skipped); |
| } |
| #endif /* CONFIG_IP_FIB_TRIE_STATS */ |
| |
| static void fib_table_print(struct seq_file *seq, struct fib_table *tb) |
| { |
| if (tb->tb_id == RT_TABLE_LOCAL) |
| seq_puts(seq, "Local:\n"); |
| else if (tb->tb_id == RT_TABLE_MAIN) |
| seq_puts(seq, "Main:\n"); |
| else |
| seq_printf(seq, "Id %d:\n", tb->tb_id); |
| } |
| |
| |
| static int fib_triestat_seq_show(struct seq_file *seq, void *v) |
| { |
| struct net *net = (struct net *)seq->private; |
| unsigned int h; |
| |
| seq_printf(seq, |
| "Basic info: size of leaf:" |
| " %Zd bytes, size of tnode: %Zd bytes.\n", |
| sizeof(struct leaf), sizeof(struct tnode)); |
| |
| for (h = 0; h < FIB_TABLE_HASHSZ; h++) { |
| struct hlist_head *head = &net->ipv4.fib_table_hash[h]; |
| struct hlist_node *node; |
| struct fib_table *tb; |
| |
| hlist_for_each_entry_rcu(tb, node, head, tb_hlist) { |
| struct trie *t = (struct trie *) tb->tb_data; |
| struct trie_stat stat; |
| |
| if (!t) |
| continue; |
| |
| fib_table_print(seq, tb); |
| |
| trie_collect_stats(t, &stat); |
| trie_show_stats(seq, &stat); |
| #ifdef CONFIG_IP_FIB_TRIE_STATS |
| trie_show_usage(seq, &t->stats); |
| #endif |
| } |
| } |
| |
| return 0; |
| } |
| |
| static int fib_triestat_seq_open(struct inode *inode, struct file *file) |
| { |
| return single_open_net(inode, file, fib_triestat_seq_show); |
| } |
| |
| static const struct file_operations fib_triestat_fops = { |
| .owner = THIS_MODULE, |
| .open = fib_triestat_seq_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = single_release_net, |
| }; |
| |
| static struct rt_trie_node *fib_trie_get_idx(struct seq_file *seq, loff_t pos) |
| { |
| struct fib_trie_iter *iter = seq->private; |
| struct net *net = seq_file_net(seq); |
| loff_t idx = 0; |
| unsigned int h; |
| |
| for (h = 0; h < FIB_TABLE_HASHSZ; h++) { |
| struct hlist_head *head = &net->ipv4.fib_table_hash[h]; |
| struct hlist_node *node; |
| struct fib_table *tb; |
| |
| hlist_for_each_entry_rcu(tb, node, head, tb_hlist) { |
| struct rt_trie_node *n; |
| |
| for (n = fib_trie_get_first(iter, |
| (struct trie *) tb->tb_data); |
| n; n = fib_trie_get_next(iter)) |
| if (pos == idx++) { |
| iter->tb = tb; |
| return n; |
| } |
| } |
| } |
| |
| return NULL; |
| } |
| |
| static void *fib_trie_seq_start(struct seq_file *seq, loff_t *pos) |
| __acquires(RCU) |
| { |
| rcu_read_lock(); |
| return fib_trie_get_idx(seq, *pos); |
| } |
| |
| static void *fib_trie_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| { |
| struct fib_trie_iter *iter = seq->private; |
| struct net *net = seq_file_net(seq); |
| struct fib_table *tb = iter->tb; |
| struct hlist_node *tb_node; |
| unsigned int h; |
| struct rt_trie_node *n; |
| |
| ++*pos; |
| /* next node in same table */ |
| n = fib_trie_get_next(iter); |
| if (n) |
| return n; |
| |
| /* walk rest of this hash chain */ |
| h = tb->tb_id & (FIB_TABLE_HASHSZ - 1); |
| while ((tb_node = rcu_dereference(hlist_next_rcu(&tb->tb_hlist)))) { |
| tb = hlist_entry(tb_node, struct fib_table, tb_hlist); |
| n = fib_trie_get_first(iter, (struct trie *) tb->tb_data); |
| if (n) |
| goto found; |
| } |
| |
| /* new hash chain */ |
| while (++h < FIB_TABLE_HASHSZ) { |
| struct hlist_head *head = &net->ipv4.fib_table_hash[h]; |
| hlist_for_each_entry_rcu(tb, tb_node, head, tb_hlist) { |
| n = fib_trie_get_first(iter, (struct trie *) tb->tb_data); |
| if (n) |
| goto found; |
| } |
| } |
| return NULL; |
| |
| found: |
| iter->tb = tb; |
| return n; |
| } |
| |
| static void fib_trie_seq_stop(struct seq_file *seq, void *v) |
| __releases(RCU) |
| { |
| rcu_read_unlock(); |
| } |
| |
| static void seq_indent(struct seq_file *seq, int n) |
| { |
| while (n-- > 0) |
| seq_puts(seq, " "); |
| } |
| |
| static inline const char *rtn_scope(char *buf, size_t len, enum rt_scope_t s) |
| { |
| switch (s) { |
| case RT_SCOPE_UNIVERSE: return "universe"; |
| case RT_SCOPE_SITE: return "site"; |
| case RT_SCOPE_LINK: return "link"; |
| case RT_SCOPE_HOST: return "host"; |
| case RT_SCOPE_NOWHERE: return "nowhere"; |
| default: |
| snprintf(buf, len, "scope=%d", s); |
| return buf; |
| } |
| } |
| |
| static const char *const rtn_type_names[__RTN_MAX] = { |
| [RTN_UNSPEC] = "UNSPEC", |
| [RTN_UNICAST] = "UNICAST", |
| [RTN_LOCAL] = "LOCAL", |
| [RTN_BROADCAST] = "BROADCAST", |
| [RTN_ANYCAST] = "ANYCAST", |
| [RTN_MULTICAST] = "MULTICAST", |
| [RTN_BLACKHOLE] = "BLACKHOLE", |
| [RTN_UNREACHABLE] = "UNREACHABLE", |
| [RTN_PROHIBIT] = "PROHIBIT", |
| [RTN_THROW] = "THROW", |
| [RTN_NAT] = "NAT", |
| [RTN_XRESOLVE] = "XRESOLVE", |
| }; |
| |
| static inline const char *rtn_type(char *buf, size_t len, unsigned int t) |
| { |
| if (t < __RTN_MAX && rtn_type_names[t]) |
| return rtn_type_names[t]; |
| snprintf(buf, len, "type %u", t); |
| return buf; |
| } |
| |
| /* Pretty print the trie */ |
| static int fib_trie_seq_show(struct seq_file *seq, void *v) |
| { |
| const struct fib_trie_iter *iter = seq->private; |
| struct rt_trie_node *n = v; |
| |
| if (!node_parent_rcu(n)) |
| fib_table_print(seq, iter->tb); |
| |
| if (IS_TNODE(n)) { |
| struct tnode *tn = (struct tnode *) n; |
| __be32 prf = htonl(mask_pfx(tn->key, tn->pos)); |
| |
| seq_indent(seq, iter->depth-1); |
| seq_printf(seq, " +-- %pI4/%d %d %d %d\n", |
| &prf, tn->pos, tn->bits, tn->full_children, |
| tn->empty_children); |
| |
| } else { |
| struct leaf *l = (struct leaf *) n; |
| struct leaf_info *li; |
| struct hlist_node *node; |
| __be32 val = htonl(l->key); |
| |
| seq_indent(seq, iter->depth); |
| seq_printf(seq, " |-- %pI4\n", &val); |
| |
| hlist_for_each_entry_rcu(li, node, &l->list, hlist) { |
| struct fib_alias *fa; |
| |
| list_for_each_entry_rcu(fa, &li->falh, fa_list) { |
| char buf1[32], buf2[32]; |
| |
| seq_indent(seq, iter->depth+1); |
| seq_printf(seq, " /%d %s %s", li->plen, |
| rtn_scope(buf1, sizeof(buf1), |
| fa->fa_info->fib_scope), |
| rtn_type(buf2, sizeof(buf2), |
| fa->fa_type)); |
| if (fa->fa_tos) |
| seq_printf(seq, " tos=%d", fa->fa_tos); |
| seq_putc(seq, '\n'); |
| } |
| } |
| } |
| |
| return 0; |
| } |
| |
| static const struct seq_operations fib_trie_seq_ops = { |
| .start = fib_trie_seq_start, |
| .next = fib_trie_seq_next, |
| .stop = fib_trie_seq_stop, |
| .show = fib_trie_seq_show, |
| }; |
| |
| static int fib_trie_seq_open(struct inode *inode, struct file *file) |
| { |
| return seq_open_net(inode, file, &fib_trie_seq_ops, |
| sizeof(struct fib_trie_iter)); |
| } |
| |
| static const struct file_operations fib_trie_fops = { |
| .owner = THIS_MODULE, |
| .open = fib_trie_seq_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release_net, |
| }; |
| |
| struct fib_route_iter { |
| struct seq_net_private p; |
| struct trie *main_trie; |
| loff_t pos; |
| t_key key; |
| }; |
| |
| static struct leaf *fib_route_get_idx(struct fib_route_iter *iter, loff_t pos) |
| { |
| struct leaf *l = NULL; |
| struct trie *t = iter->main_trie; |
| |
| /* use cache location of last found key */ |
| if (iter->pos > 0 && pos >= iter->pos && (l = fib_find_node(t, iter->key))) |
| pos -= iter->pos; |
| else { |
| iter->pos = 0; |
| l = trie_firstleaf(t); |
| } |
| |
| while (l && pos-- > 0) { |
| iter->pos++; |
| l = trie_nextleaf(l); |
| } |
| |
| if (l) |
| iter->key = pos; /* remember it */ |
| else |
| iter->pos = 0; /* forget it */ |
| |
| return l; |
| } |
| |
| static void *fib_route_seq_start(struct seq_file *seq, loff_t *pos) |
| __acquires(RCU) |
| { |
| struct fib_route_iter *iter = seq->private; |
| struct fib_table *tb; |
| |
| rcu_read_lock(); |
| tb = fib_get_table(seq_file_net(seq), RT_TABLE_MAIN); |
| if (!tb) |
| return NULL; |
| |
| iter->main_trie = (struct trie *) tb->tb_data; |
| if (*pos == 0) |
| return SEQ_START_TOKEN; |
| else |
| return fib_route_get_idx(iter, *pos - 1); |
| } |
| |
| static void *fib_route_seq_next(struct seq_file *seq, void *v, loff_t *pos) |
| { |
| struct fib_route_iter *iter = seq->private; |
| struct leaf *l = v; |
| |
| ++*pos; |
| if (v == SEQ_START_TOKEN) { |
| iter->pos = 0; |
| l = trie_firstleaf(iter->main_trie); |
| } else { |
| iter->pos++; |
| l = trie_nextleaf(l); |
| } |
| |
| if (l) |
| iter->key = l->key; |
| else |
| iter->pos = 0; |
| return l; |
| } |
| |
| static void fib_route_seq_stop(struct seq_file *seq, void *v) |
| __releases(RCU) |
| { |
| rcu_read_unlock(); |
| } |
| |
| static unsigned int fib_flag_trans(int type, __be32 mask, const struct fib_info *fi) |
| { |
| unsigned int flags = 0; |
| |
| if (type == RTN_UNREACHABLE || type == RTN_PROHIBIT) |
| flags = RTF_REJECT; |
| if (fi && fi->fib_nh->nh_gw) |
| flags |= RTF_GATEWAY; |
| if (mask == htonl(0xFFFFFFFF)) |
| flags |= RTF_HOST; |
| flags |= RTF_UP; |
| return flags; |
| } |
| |
| /* |
| * This outputs /proc/net/route. |
| * The format of the file is not supposed to be changed |
| * and needs to be same as fib_hash output to avoid breaking |
| * legacy utilities |
| */ |
| static int fib_route_seq_show(struct seq_file *seq, void *v) |
| { |
| struct leaf *l = v; |
| struct leaf_info *li; |
| struct hlist_node *node; |
| |
| if (v == SEQ_START_TOKEN) { |
| seq_printf(seq, "%-127s\n", "Iface\tDestination\tGateway " |
| "\tFlags\tRefCnt\tUse\tMetric\tMask\t\tMTU" |
| "\tWindow\tIRTT"); |
| return 0; |
| } |
| |
| hlist_for_each_entry_rcu(li, node, &l->list, hlist) { |
| struct fib_alias *fa; |
| __be32 mask, prefix; |
| |
| mask = inet_make_mask(li->plen); |
| prefix = htonl(l->key); |
| |
| list_for_each_entry_rcu(fa, &li->falh, fa_list) { |
| const struct fib_info *fi = fa->fa_info; |
| unsigned int flags = fib_flag_trans(fa->fa_type, mask, fi); |
| int len; |
| |
| if (fa->fa_type == RTN_BROADCAST |
| || fa->fa_type == RTN_MULTICAST) |
| continue; |
| |
| if (fi) |
| seq_printf(seq, |
| "%s\t%08X\t%08X\t%04X\t%d\t%u\t" |
| "%d\t%08X\t%d\t%u\t%u%n", |
| fi->fib_dev ? fi->fib_dev->name : "*", |
| prefix, |
| fi->fib_nh->nh_gw, flags, 0, 0, |
| fi->fib_priority, |
| mask, |
| (fi->fib_advmss ? |
| fi->fib_advmss + 40 : 0), |
| fi->fib_window, |
| fi->fib_rtt >> 3, &len); |
| else |
| seq_printf(seq, |
| "*\t%08X\t%08X\t%04X\t%d\t%u\t" |
| "%d\t%08X\t%d\t%u\t%u%n", |
| prefix, 0, flags, 0, 0, 0, |
| mask, 0, 0, 0, &len); |
| |
| seq_printf(seq, "%*s\n", 127 - len, ""); |
| } |
| } |
| |
| return 0; |
| } |
| |
| static const struct seq_operations fib_route_seq_ops = { |
| .start = fib_route_seq_start, |
| .next = fib_route_seq_next, |
| .stop = fib_route_seq_stop, |
| .show = fib_route_seq_show, |
| }; |
| |
| static int fib_route_seq_open(struct inode *inode, struct file *file) |
| { |
| return seq_open_net(inode, file, &fib_route_seq_ops, |
| sizeof(struct fib_route_iter)); |
| } |
| |
| static const struct file_operations fib_route_fops = { |
| .owner = THIS_MODULE, |
| .open = fib_route_seq_open, |
| .read = seq_read, |
| .llseek = seq_lseek, |
| .release = seq_release_net, |
| }; |
| |
| int __net_init fib_proc_init(struct net *net) |
| { |
| if (!proc_net_fops_create(net, "fib_trie", S_IRUGO, &fib_trie_fops)) |
| goto out1; |
| |
| if (!proc_net_fops_create(net, "fib_triestat", S_IRUGO, |
| &fib_triestat_fops)) |
| goto out2; |
| |
| if (!proc_net_fops_create(net, "route", S_IRUGO, &fib_route_fops)) |
| goto out3; |
| |
| return 0; |
| |
| out3: |
| proc_net_remove(net, "fib_triestat"); |
| out2: |
| proc_net_remove(net, "fib_trie"); |
| out1: |
| return -ENOMEM; |
| } |
| |
| void __net_exit fib_proc_exit(struct net *net) |
| { |
| proc_net_remove(net, "fib_trie"); |
| proc_net_remove(net, "fib_triestat"); |
| proc_net_remove(net, "route"); |
| } |
| |
| #endif /* CONFIG_PROC_FS */ |