--- /dev/null
+/*
+ * 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/jhash.h>
+#include <linux/netlink.h>
+#include <linux/netfilter.h>
+#include <linux/netfilter/nf_tables.h>
+#include <net/netfilter/nf_tables.h>
+
+struct nft_hash {
+ struct hlist_head *hash;
+ unsigned int hsize;
+};
+
+struct nft_hash_elem {
+ struct hlist_node hnode;
+ struct nft_data key;
+ struct nft_data data[];
+};
+
+static u32 nft_hash_rnd __read_mostly;
+static bool nft_hash_rnd_initted __read_mostly;
+
+static unsigned int nft_hash_data(const struct nft_data *data,
+ unsigned int hsize, unsigned int len)
+{
+ unsigned int h;
+
+ h = jhash(data->data, len, nft_hash_rnd);
+ return ((u64)h * hsize) >> 32;
+}
+
+static bool nft_hash_lookup(const struct nft_set *set,
+ const struct nft_data *key,
+ struct nft_data *data)
+{
+ const struct nft_hash *priv = nft_set_priv(set);
+ const struct nft_hash_elem *he;
+ unsigned int h;
+
+ h = nft_hash_data(key, priv->hsize, set->klen);
+ hlist_for_each_entry(he, &priv->hash[h], hnode) {
+ if (nft_data_cmp(&he->key, key, set->klen))
+ continue;
+ if (set->flags & NFT_SET_MAP)
+ nft_data_copy(data, he->data);
+ return true;
+ }
+ return false;
+}
+
+static void nft_hash_elem_destroy(const struct nft_set *set,
+ struct nft_hash_elem *he)
+{
+ nft_data_uninit(&he->key, NFT_DATA_VALUE);
+ if (set->flags & NFT_SET_MAP)
+ nft_data_uninit(he->data, set->dtype);
+ kfree(he);
+}
+
+static int nft_hash_insert(const struct nft_set *set,
+ const struct nft_set_elem *elem)
+{
+ struct nft_hash *priv = nft_set_priv(set);
+ struct nft_hash_elem *he;
+ unsigned int size, h;
+
+ if (elem->flags != 0)
+ return -EINVAL;
+
+ size = sizeof(*he);
+ if (set->flags & NFT_SET_MAP)
+ size += sizeof(he->data[0]);
+
+ he = kzalloc(size, GFP_KERNEL);
+ if (he == NULL)
+ return -ENOMEM;
+
+ nft_data_copy(&he->key, &elem->key);
+ if (set->flags & NFT_SET_MAP)
+ nft_data_copy(he->data, &elem->data);
+
+ h = nft_hash_data(&he->key, priv->hsize, set->klen);
+ hlist_add_head_rcu(&he->hnode, &priv->hash[h]);
+ return 0;
+}
+
+static void nft_hash_remove(const struct nft_set *set,
+ const struct nft_set_elem *elem)
+{
+ struct nft_hash_elem *he = elem->cookie;
+
+ hlist_del_rcu(&he->hnode);
+ kfree(he);
+}
+
+static int nft_hash_get(const struct nft_set *set, struct nft_set_elem *elem)
+{
+ const struct nft_hash *priv = nft_set_priv(set);
+ struct nft_hash_elem *he;
+ unsigned int h;
+
+ h = nft_hash_data(&elem->key, priv->hsize, set->klen);
+ hlist_for_each_entry(he, &priv->hash[h], hnode) {
+ if (nft_data_cmp(&he->key, &elem->key, set->klen))
+ continue;
+
+ elem->cookie = he;
+ elem->flags = 0;
+ if (set->flags & NFT_SET_MAP)
+ nft_data_copy(&elem->data, he->data);
+ return 0;
+ }
+ return -ENOENT;
+}
+
+static void nft_hash_walk(const struct nft_ctx *ctx, const struct nft_set *set,
+ struct nft_set_iter *iter)
+{
+ const struct nft_hash *priv = nft_set_priv(set);
+ const struct nft_hash_elem *he;
+ struct nft_set_elem elem;
+ unsigned int i;
+
+ for (i = 0; i < priv->hsize; i++) {
+ hlist_for_each_entry(he, &priv->hash[i], hnode) {
+ if (iter->count < iter->skip)
+ goto cont;
+
+ memcpy(&elem.key, &he->key, sizeof(elem.key));
+ if (set->flags & NFT_SET_MAP)
+ memcpy(&elem.data, he->data, sizeof(elem.data));
+ elem.flags = 0;
+
+ iter->err = iter->fn(ctx, set, iter, &elem);
+ if (iter->err < 0)
+ return;
+cont:
+ iter->count++;
+ }
+ }
+}
+
+static unsigned int nft_hash_privsize(const struct nlattr * const nla[])
+{
+ return sizeof(struct nft_hash);
+}
+
+static int nft_hash_init(const struct nft_set *set,
+ const struct nlattr * const tb[])
+{
+ struct nft_hash *priv = nft_set_priv(set);
+ unsigned int cnt, i;
+
+ if (unlikely(!nft_hash_rnd_initted)) {
+ get_random_bytes(&nft_hash_rnd, 4);
+ nft_hash_rnd_initted = true;
+ }
+
+ /* Aim for a load factor of 0.75 */
+ // FIXME: temporarily broken until we have set descriptions
+ cnt = 100;
+ cnt = cnt * 4 / 3;
+
+ priv->hash = kcalloc(cnt, sizeof(struct hlist_head), GFP_KERNEL);
+ if (priv->hash == NULL)
+ return -ENOMEM;
+ priv->hsize = cnt;
+
+ for (i = 0; i < cnt; i++)
+ INIT_HLIST_HEAD(&priv->hash[i]);
+
+ return 0;
+}
+
+static void nft_hash_destroy(const struct nft_set *set)
+{
+ const struct nft_hash *priv = nft_set_priv(set);
+ const struct hlist_node *next;
+ struct nft_hash_elem *elem;
+ unsigned int i;
+
+ for (i = 0; i < priv->hsize; i++) {
+ hlist_for_each_entry_safe(elem, next, &priv->hash[i], hnode) {
+ hlist_del(&elem->hnode);
+ nft_hash_elem_destroy(set, elem);
+ }
+ }
+ kfree(priv->hash);
+}
+
+static struct nft_set_ops nft_hash_ops __read_mostly = {
+ .privsize = nft_hash_privsize,
+ .init = nft_hash_init,
+ .destroy = nft_hash_destroy,
+ .get = nft_hash_get,
+ .insert = nft_hash_insert,
+ .remove = nft_hash_remove,
+ .lookup = nft_hash_lookup,
+ .walk = nft_hash_walk,
+ .features = NFT_SET_MAP,
+ .owner = THIS_MODULE,
+};
+
+static int __init nft_hash_module_init(void)
+{
+ return nft_register_set(&nft_hash_ops);
+}
+
+static void __exit nft_hash_module_exit(void)
+{
+ nft_unregister_set(&nft_hash_ops);
+}
+
+module_init(nft_hash_module_init);
+module_exit(nft_hash_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>");
+MODULE_ALIAS_NFT_SET();
projects / karo-tx-linux.git / blobdiff