nft_rbtree.c
/*
* Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* Development of this code funded by Astaro AG (http://www.astaro.com/)
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/list.h>
#include <linux/rbtree.h>
#include <linux/netlink.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
static DEFINE_SPINLOCK(nft_rbtree_lock);
struct nft_rbtree {
struct rb_root root;
};
struct nft_rbtree_elem {
struct rb_node node;
u16 flags;
struct nft_data key;
struct nft_data data[];
};
static bool nft_rbtree_lookup(const struct nft_set *set,
const struct nft_data *key,
struct nft_data *data)
{
const struct nft_rbtree *priv = nft_set_priv(set);
const struct nft_rbtree_elem *rbe, *interval = NULL;
const struct rb_node *parent = priv->root.rb_node;
int d;
spin_lock_bh(&nft_rbtree_lock);
while (parent != NULL) {
rbe = rb_entry(parent, struct nft_rbtree_elem, node);
d = nft_data_cmp(&rbe->key, key, set->klen);
if (d < 0) {
parent = parent->rb_left;
interval = rbe;
} else if (d > 0)
parent = parent->rb_right;
else {
found:
if (rbe->flags & NFT_SET_ELEM_INTERVAL_END)
goto out;
if (set->flags & NFT_SET_MAP)
nft_data_copy(data, rbe->data);
spin_unlock_bh(&nft_rbtree_lock);
return true;
}
}
if (set->flags & NFT_SET_INTERVAL && interval != NULL) {
rbe = interval;
goto found;
}
out:
spin_unlock_bh(&nft_rbtree_lock);
return false;
}
static void nft_rbtree_elem_destroy(const struct nft_set *set,
struct nft_rbtree_elem *rbe)
{
nft_data_uninit(&rbe->key, NFT_DATA_VALUE);
if (set->flags & NFT_SET_MAP &&
!(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
nft_data_uninit(rbe->data, set->dtype);
kfree(rbe);
}
static int __nft_rbtree_insert(const struct nft_set *set,
struct nft_rbtree_elem *new)
{
struct nft_rbtree *priv = nft_set_priv(set);
struct nft_rbtree_elem *rbe;
struct rb_node *parent, **p;
int d;
parent = NULL;
p = &priv->root.rb_node;
while (*p != NULL) {
parent = *p;
rbe = rb_entry(parent, struct nft_rbtree_elem, node);
d = nft_data_cmp(&rbe->key, &new->key, set->klen);
if (d < 0)
p = &parent->rb_left;
else if (d > 0)
p = &parent->rb_right;
else
return -EEXIST;
}
rb_link_node(&new->node, parent, p);
rb_insert_color(&new->node, &priv->root);
return 0;
}
static int nft_rbtree_insert(const struct nft_set *set,
const struct nft_set_elem *elem)
{
struct nft_rbtree_elem *rbe;
unsigned int size;
int err;
size = sizeof(*rbe);
if (set->flags & NFT_SET_MAP &&
!(elem->flags & NFT_SET_ELEM_INTERVAL_END))
size += sizeof(rbe->data[0]);
rbe = kzalloc(size, GFP_KERNEL);
if (rbe == NULL)
return -ENOMEM;
rbe->flags = elem->flags;
nft_data_copy(&rbe->key, &elem->key);
if (set->flags & NFT_SET_MAP &&
!(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
nft_data_copy(rbe->data, &elem->data);
spin_lock_bh(&nft_rbtree_lock);
err = __nft_rbtree_insert(set, rbe);
if (err < 0)
kfree(rbe);
spin_unlock_bh(&nft_rbtree_lock);
return err;
}
static void nft_rbtree_remove(const struct nft_set *set,
const struct nft_set_elem *elem)
{
struct nft_rbtree *priv = nft_set_priv(set);
struct nft_rbtree_elem *rbe = elem->cookie;
spin_lock_bh(&nft_rbtree_lock);
rb_erase(&rbe->node, &priv->root);
spin_unlock_bh(&nft_rbtree_lock);
kfree(rbe);
}
static int nft_rbtree_get(const struct nft_set *set, struct nft_set_elem *elem)
{
const struct nft_rbtree *priv = nft_set_priv(set);
const struct rb_node *parent = priv->root.rb_node;
struct nft_rbtree_elem *rbe;
int d;
spin_lock_bh(&nft_rbtree_lock);
while (parent != NULL) {
rbe = rb_entry(parent, struct nft_rbtree_elem, node);
d = nft_data_cmp(&rbe->key, &elem->key, set->klen);
if (d < 0)
parent = parent->rb_left;
else if (d > 0)
parent = parent->rb_right;
else {
elem->cookie = rbe;
if (set->flags & NFT_SET_MAP &&
!(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
nft_data_copy(&elem->data, rbe->data);
elem->flags = rbe->flags;
spin_unlock_bh(&nft_rbtree_lock);
return 0;
}
}
spin_unlock_bh(&nft_rbtree_lock);
return -ENOENT;
}
static void nft_rbtree_walk(const struct nft_ctx *ctx,
const struct nft_set *set,
struct nft_set_iter *iter)
{
const struct nft_rbtree *priv = nft_set_priv(set);
const struct nft_rbtree_elem *rbe;
struct nft_set_elem elem;
struct rb_node *node;
spin_lock_bh(&nft_rbtree_lock);
for (node = rb_first(&priv->root); node != NULL; node = rb_next(node)) {
if (iter->count < iter->skip)
goto cont;
rbe = rb_entry(node, struct nft_rbtree_elem, node);
nft_data_copy(&elem.key, &rbe->key);
if (set->flags & NFT_SET_MAP &&
!(rbe->flags & NFT_SET_ELEM_INTERVAL_END))
nft_data_copy(&elem.data, rbe->data);
elem.flags = rbe->flags;
iter->err = iter->fn(ctx, set, iter, &elem);
if (iter->err < 0) {
spin_unlock_bh(&nft_rbtree_lock);
return;
}
cont:
iter->count++;
}
spin_unlock_bh(&nft_rbtree_lock);
}
static unsigned int nft_rbtree_privsize(const struct nlattr * const nla[])
{
return sizeof(struct nft_rbtree);
}
static int nft_rbtree_init(const struct nft_set *set,
const struct nft_set_desc *desc,
const struct nlattr * const nla[])
{
struct nft_rbtree *priv = nft_set_priv(set);
priv->root = RB_ROOT;
return 0;
}
static void nft_rbtree_destroy(const struct nft_set *set)
{
struct nft_rbtree *priv = nft_set_priv(set);
struct nft_rbtree_elem *rbe;
struct rb_node *node;
spin_lock_bh(&nft_rbtree_lock);
while ((node = priv->root.rb_node) != NULL) {
rb_erase(node, &priv->root);
rbe = rb_entry(node, struct nft_rbtree_elem, node);
nft_rbtree_elem_destroy(set, rbe);
}
spin_unlock_bh(&nft_rbtree_lock);
}
static bool nft_rbtree_estimate(const struct nft_set_desc *desc, u32 features,
struct nft_set_estimate *est)
{
unsigned int nsize;
nsize = sizeof(struct nft_rbtree_elem);
if (features & NFT_SET_MAP)
nsize += FIELD_SIZEOF(struct nft_rbtree_elem, data[0]);
if (desc->size)
est->size = sizeof(struct nft_rbtree) + desc->size * nsize;
else
est->size = nsize;
est->class = NFT_SET_CLASS_O_LOG_N;
return true;
}
static struct nft_set_ops nft_rbtree_ops __read_mostly = {
.privsize = nft_rbtree_privsize,
.estimate = nft_rbtree_estimate,
.init = nft_rbtree_init,
.destroy = nft_rbtree_destroy,
.insert = nft_rbtree_insert,
.remove = nft_rbtree_remove,
.get = nft_rbtree_get,
.lookup = nft_rbtree_lookup,
.walk = nft_rbtree_walk,
.features = NFT_SET_INTERVAL | NFT_SET_MAP,
.owner = THIS_MODULE,
};
static int __init nft_rbtree_module_init(void)
{
return nft_register_set(&nft_rbtree_ops);
}
static void __exit nft_rbtree_module_exit(void)
{
nft_unregister_set(&nft_rbtree_ops);
}
module_init(nft_rbtree_module_init);
module_exit(nft_rbtree_module_exit);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
MODULE_ALIAS_NFT_SET();