diff options
Diffstat (limited to 'net/netfilter/nft_set.c')
| -rw-r--r-- | net/netfilter/nft_set.c | 381 |
1 files changed, 381 insertions, 0 deletions
diff --git a/net/netfilter/nft_set.c b/net/netfilter/nft_set.c new file mode 100644 index 000000000000..7b7c8354c327 --- /dev/null +++ b/net/netfilter/nft_set.c @@ -0,0 +1,381 @@ +/* + * Copyright (c) 2008 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/module.h> +#include <linux/init.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> + +struct nft_set { + struct rb_root root; + enum nft_registers sreg:8; + enum nft_registers dreg:8; + u8 klen; + u8 dlen; + u16 flags; +}; + +struct nft_set_elem { + struct rb_node node; + enum nft_set_elem_flags flags; + struct nft_data key; + struct nft_data data[]; +}; + +static void nft_set_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + const struct nft_set *priv = nft_expr_priv(expr); + const struct rb_node *parent = priv->root.rb_node; + const struct nft_set_elem *elem, *interval = NULL; + const struct nft_data *key = &data[priv->sreg]; + int d; + + while (parent != NULL) { + elem = rb_entry(parent, struct nft_set_elem, node); + + d = nft_data_cmp(&elem->key, key, priv->klen); + if (d < 0) { + parent = parent->rb_left; + interval = elem; + } else if (d > 0) + parent = parent->rb_right; + else { +found: + if (elem->flags & NFT_SE_INTERVAL_END) + goto out; + if (priv->flags & NFT_SET_MAP) + nft_data_copy(&data[priv->dreg], elem->data); + return; + } + } + + if (priv->flags & NFT_SET_INTERVAL && interval != NULL) { + elem = interval; + goto found; + } +out: + data[NFT_REG_VERDICT].verdict = NFT_BREAK; +} + +static void nft_set_elem_destroy(const struct nft_expr *expr, + struct nft_set_elem *elem) +{ + const struct nft_set *priv = nft_expr_priv(expr); + + nft_data_uninit(&elem->key, NFT_DATA_VALUE); + if (priv->flags & NFT_SET_MAP) + nft_data_uninit(elem->data, nft_dreg_to_type(priv->dreg)); + kfree(elem); +} + +static const struct nla_policy nft_se_policy[NFTA_SE_MAX + 1] = { + [NFTA_SE_KEY] = { .type = NLA_NESTED }, + [NFTA_SE_DATA] = { .type = NLA_NESTED }, + [NFTA_SE_FLAGS] = { .type = NLA_U32 }, +}; + +static int nft_set_elem_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr *nla, + struct nft_set_elem **new) +{ + struct nft_set *priv = nft_expr_priv(expr); + struct nlattr *tb[NFTA_SE_MAX + 1]; + struct nft_set_elem *elem; + struct nft_data_desc d1, d2; + enum nft_set_elem_flags flags = 0; + unsigned int size; + int err; + + err = nla_parse_nested(tb, NFTA_SE_MAX, nla, nft_se_policy); + if (err < 0) + return err; + + if (tb[NFTA_SE_KEY] == NULL) + return -EINVAL; + + if (tb[NFTA_SE_FLAGS] != NULL) { + flags = ntohl(nla_get_be32(tb[NFTA_SE_FLAGS])); + if (flags & ~NFT_SE_INTERVAL_END) + return -EINVAL; + } + + size = sizeof(*elem); + if (priv->flags & NFT_SET_MAP) { + if (tb[NFTA_SE_DATA] == NULL && !(flags & NFT_SE_INTERVAL_END)) + return -EINVAL; + size += sizeof(elem->data[0]); + } else { + if (tb[NFTA_SE_DATA] != NULL) + return -EINVAL; + } + + elem = kzalloc(size, GFP_KERNEL); + if (elem == NULL) + return -ENOMEM; + elem->flags = flags; + + err = nft_data_init(ctx, &elem->key, &d1, tb[NFTA_SE_KEY]); + if (err < 0) + goto err1; + err = -EINVAL; + if (d1.type != NFT_DATA_VALUE || d1.len != priv->klen) + goto err2; + + if (tb[NFTA_SE_DATA] != NULL) { + err = nft_data_init(ctx, elem->data, &d2, tb[NFTA_SE_DATA]); + if (err < 0) + goto err2; + err = -EINVAL; + if (priv->dreg != NFT_REG_VERDICT && d2.len != priv->dlen) + goto err2; + err = nft_validate_data_load(ctx, priv->dreg, elem->data, d2.type); + if (err < 0) + goto err3; + } + + *new = elem; + return 0; + +err3: + nft_data_uninit(elem->data, d2.type); +err2: + nft_data_uninit(&elem->key, d1.type); +err1: + kfree(elem); + return err; +} + +static int nft_set_elem_dump(struct sk_buff *skb, const struct nft_expr *expr, + const struct nft_set_elem *elem) + +{ + const struct nft_set *priv = nft_expr_priv(expr); + struct nlattr *nest; + + nest = nla_nest_start(skb, NFTA_LIST_ELEM); + if (nest == NULL) + goto nla_put_failure; + + if (nft_data_dump(skb, NFTA_SE_KEY, &elem->key, + NFT_DATA_VALUE, priv->klen) < 0) + goto nla_put_failure; + + if (priv->flags & NFT_SET_MAP && !(elem->flags & NFT_SE_INTERVAL_END)) { + if (nft_data_dump(skb, NFTA_SE_DATA, elem->data, + nft_dreg_to_type(priv->dreg), priv->dlen) < 0) + goto nla_put_failure; + } + + if (elem->flags){ + if (nla_put_be32(skb, NFTA_SE_FLAGS, htonl(elem->flags))) + goto nla_put_failure; + } + + nla_nest_end(skb, nest); + return 0; + +nla_put_failure: + return -1; +} + +static void nft_set_destroy(const struct nft_expr *expr) +{ + struct nft_set *priv = nft_expr_priv(expr); + struct nft_set_elem *elem; + struct rb_node *node; + + while ((node = priv->root.rb_node) != NULL) { + rb_erase(node, &priv->root); + elem = rb_entry(node, struct nft_set_elem, node); + nft_set_elem_destroy(expr, elem); + } +} + +static const struct nla_policy nft_set_policy[NFTA_SET_MAX + 1] = { + [NFTA_SET_FLAGS] = { .type = NLA_U32 }, + [NFTA_SET_SREG] = { .type = NLA_U32 }, + [NFTA_SET_DREG] = { .type = NLA_U32 }, + [NFTA_SET_KLEN] = { .type = NLA_U32 }, + [NFTA_SET_DLEN] = { .type = NLA_U32 }, + [NFTA_SET_ELEMENTS] = { .type = NLA_NESTED }, +}; + +static int nft_set_init(const struct nft_ctx *ctx, const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_set *priv = nft_expr_priv(expr); + struct nft_set_elem *elem, *uninitialized_var(new); + struct rb_node *parent, **p; + const struct nlattr *nla; + int err, rem, d; + + if (tb[NFTA_SET_SREG] == NULL || + tb[NFTA_SET_KLEN] == NULL || + tb[NFTA_SET_ELEMENTS] == NULL) + return -EINVAL; + + priv->root = RB_ROOT; + + if (tb[NFTA_SET_FLAGS] != NULL) { + priv->flags = ntohl(nla_get_be32(tb[NFTA_SET_FLAGS])); + if (priv->flags & ~(NFT_SET_INTERVAL | NFT_SET_MAP)) + return -EINVAL; + } + + priv->sreg = ntohl(nla_get_be32(tb[NFTA_SET_SREG])); + err = nft_validate_input_register(priv->sreg); + if (err < 0) + return err; + + if (tb[NFTA_SET_DREG] != NULL) { + if (!(priv->flags & NFT_SET_MAP)) + return -EINVAL; + if (tb[NFTA_SET_DLEN] == NULL) + return -EINVAL; + + priv->dreg = ntohl(nla_get_be32(tb[NFTA_SET_DREG])); + err = nft_validate_output_register(priv->dreg); + if (err < 0) + return err; + + if (priv->dreg == NFT_REG_VERDICT) + priv->dlen = FIELD_SIZEOF(struct nft_data, data); + else { + priv->dlen = ntohl(nla_get_be32(tb[NFTA_SET_DLEN])); + if (priv->dlen == 0 || + priv->dlen > FIELD_SIZEOF(struct nft_data, data)) + return -EINVAL; + } + } else { + if (priv->flags & NFT_SET_MAP) + return -EINVAL; + if (tb[NFTA_SET_DLEN] != NULL) + return -EINVAL; + } + + priv->klen = ntohl(nla_get_be32(tb[NFTA_SET_KLEN])); + if (priv->klen == 0 || + priv->klen > FIELD_SIZEOF(struct nft_data, data)) + return -EINVAL; + + nla_for_each_nested(nla, tb[NFTA_SET_ELEMENTS], rem) { + err = -EINVAL; + if (nla_type(nla) != NFTA_LIST_ELEM) + goto err1; + + err = nft_set_elem_init(ctx, expr, nla, &new); + if (err < 0) + goto err1; + + parent = NULL; + p = &priv->root.rb_node; + while (*p != NULL) { + parent = *p; + elem = rb_entry(parent, struct nft_set_elem, node); + d = nft_data_cmp(&elem->key, &new->key, priv->klen); + if (d < 0) + p = &parent->rb_left; + else if (d > 0) + p = &parent->rb_right; + else { + err = -EEXIST; + goto err2; + } + } + rb_link_node(&new->node, parent, p); + rb_insert_color(&new->node, &priv->root); + } + + return 0; + +err2: + nft_set_elem_destroy(expr, new); +err1: + nft_set_destroy(expr); + return err; +} + +static int nft_set_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + struct nft_set *priv = nft_expr_priv(expr); + const struct nft_set_elem *elem; + struct rb_node *node; + struct nlattr *list; + + if (priv->flags) { + if (nla_put_be32(skb, NFTA_SET_FLAGS, htonl(priv->flags))) + goto nla_put_failure; + } + + if (nla_put_be32(skb, NFTA_SET_SREG, htonl(priv->sreg))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_SET_KLEN, htonl(priv->klen))) + goto nla_put_failure; + + if (priv->flags & NFT_SET_MAP) { + if (nla_put_be32(skb, NFTA_SET_DREG, htonl(priv->dreg))) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_SET_DLEN, htonl(priv->dlen))) + goto nla_put_failure; + } + + list = nla_nest_start(skb, NFTA_SET_ELEMENTS); + if (list == NULL) + goto nla_put_failure; + + for (node = rb_first(&priv->root); node; node = rb_next(node)) { + elem = rb_entry(node, struct nft_set_elem, node); + if (nft_set_elem_dump(skb, expr, elem) < 0) + goto nla_put_failure; + } + + nla_nest_end(skb, list); + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_ops nft_set_ops __read_mostly = { + .name = "set", + .size = NFT_EXPR_SIZE(sizeof(struct nft_set)), + .owner = THIS_MODULE, + .eval = nft_set_eval, + .init = nft_set_init, + .destroy = nft_set_destroy, + .dump = nft_set_dump, + .policy = nft_set_policy, + .maxattr = NFTA_SET_MAX, +}; + +static int __init nft_set_module_init(void) +{ + return nft_register_expr(&nft_set_ops); +} + +static void __exit nft_set_module_exit(void) +{ + nft_unregister_expr(&nft_set_ops); +} + +module_init(nft_set_module_init); +module_exit(nft_set_module_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Patrick McHardy <kaber@trash.net>"); +MODULE_ALIAS_NFT_EXPR("set"); |