diff options
Diffstat (limited to 'net/netfilter/nft_lookup.c')
| -rw-r--r-- | net/netfilter/nft_lookup.c | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/net/netfilter/nft_lookup.c b/net/netfilter/nft_lookup.c new file mode 100644 index 000000000000..8a6116b75b5a --- /dev/null +++ b/net/netfilter/nft_lookup.c @@ -0,0 +1,141 @@ +/* + * Copyright (c) 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/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_lookup { + struct nft_set *set; + enum nft_registers sreg:8; + enum nft_registers dreg:8; + struct nft_set_binding binding; +}; + +static void nft_lookup_eval(const struct nft_expr *expr, + struct nft_data data[NFT_REG_MAX + 1], + const struct nft_pktinfo *pkt) +{ + const struct nft_lookup *priv = nft_expr_priv(expr); + const struct nft_set *set = priv->set; + + if (set->ops->lookup(set, &data[priv->sreg], &data[priv->dreg])) + return; + data[NFT_REG_VERDICT].verdict = NFT_BREAK; +} + +static const struct nla_policy nft_lookup_policy[NFTA_LOOKUP_MAX + 1] = { + [NFTA_LOOKUP_SET] = { .type = NLA_STRING }, + [NFTA_LOOKUP_SREG] = { .type = NLA_U32 }, + [NFTA_LOOKUP_DREG] = { .type = NLA_U32 }, +}; + +static int nft_lookup_init(const struct nft_ctx *ctx, + const struct nft_expr *expr, + const struct nlattr * const tb[]) +{ + struct nft_lookup *priv = nft_expr_priv(expr); + struct nft_set *set; + int err; + + if (tb[NFTA_LOOKUP_SET] == NULL || + tb[NFTA_LOOKUP_SREG] == NULL) + return -EINVAL; + + set = nf_tables_set_lookup(ctx->table, tb[NFTA_LOOKUP_SET]); + if (IS_ERR(set)) + return PTR_ERR(set); + + priv->sreg = ntohl(nla_get_be32(tb[NFTA_LOOKUP_SREG])); + err = nft_validate_input_register(priv->sreg); + if (err < 0) + return err; + + if (tb[NFTA_LOOKUP_DREG] != NULL) { + if (!(set->flags & NFT_SET_MAP)) + return -EINVAL; + + priv->dreg = ntohl(nla_get_be32(tb[NFTA_LOOKUP_DREG])); + err = nft_validate_output_register(priv->dreg); + if (err < 0) + return err; + + if (priv->dreg == NFT_REG_VERDICT) { + if (set->dtype != NFT_DATA_VERDICT) + return -EINVAL; + } else if (set->dtype == NFT_DATA_VERDICT) + return -EINVAL; + } else if (set->flags & NFT_SET_MAP) + return -EINVAL; + + err = nf_tables_bind_set(ctx, set, &priv->binding); + if (err < 0) + return err; + + priv->set = set; + return 0; +} + +static void nft_lookup_destroy(const struct nft_expr *expr) +{ + struct nft_lookup *priv = nft_expr_priv(expr); + + nf_tables_unbind_set(NULL, priv->set, &priv->binding); +} + +static int nft_lookup_dump(struct sk_buff *skb, const struct nft_expr *expr) +{ + const struct nft_lookup *priv = nft_expr_priv(expr); + + if (nla_put_string(skb, NFTA_LOOKUP_SET, priv->set->name)) + goto nla_put_failure; + if (nla_put_be32(skb, NFTA_LOOKUP_SREG, htonl(priv->sreg))) + goto nla_put_failure; + if (priv->set->flags & NFT_SET_MAP) + if (nla_put_be32(skb, NFTA_LOOKUP_DREG, htonl(priv->dreg))) + goto nla_put_failure; + return 0; + +nla_put_failure: + return -1; +} + +static struct nft_expr_type nft_lookup_type; +static const struct nft_expr_ops nft_lookup_ops = { + .type = &nft_lookup_type, + .size = NFT_EXPR_SIZE(sizeof(struct nft_lookup)), + .eval = nft_lookup_eval, + .init = nft_lookup_init, + .destroy = nft_lookup_destroy, + .dump = nft_lookup_dump, +}; + +static struct nft_expr_type nft_lookup_type __read_mostly = { + .name = "lookup", + .ops = &nft_lookup_ops, + .policy = nft_lookup_policy, + .maxattr = NFTA_LOOKUP_MAX, + .owner = THIS_MODULE, +}; + +int __init nft_lookup_module_init(void) +{ + return nft_register_expr(&nft_lookup_type); +} + +void nft_lookup_module_exit(void) +{ + nft_unregister_expr(&nft_lookup_type); +} |