Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2009 Patrick McHardy <kaber@trash.net> |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or modify |
| 5 | * it under the terms of the GNU General Public License version 2 as |
| 6 | * published by the Free Software Foundation. |
| 7 | * |
| 8 | * Development of this code funded by Astaro AG (http://www.astaro.com/) |
| 9 | */ |
| 10 | |
| 11 | #include <linux/kernel.h> |
| 12 | #include <linux/init.h> |
| 13 | #include <linux/list.h> |
| 14 | #include <linux/rbtree.h> |
| 15 | #include <linux/netlink.h> |
| 16 | #include <linux/netfilter.h> |
| 17 | #include <linux/netfilter/nf_tables.h> |
| 18 | #include <net/netfilter/nf_tables.h> |
Rashika Kheria | bd76ed3 | 2014-02-09 22:31:42 +0530 | [diff] [blame^] | 19 | #include <net/netfilter/nf_tables_core.h> |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 20 | |
| 21 | struct nft_lookup { |
| 22 | struct nft_set *set; |
| 23 | enum nft_registers sreg:8; |
| 24 | enum nft_registers dreg:8; |
| 25 | struct nft_set_binding binding; |
| 26 | }; |
| 27 | |
| 28 | static void nft_lookup_eval(const struct nft_expr *expr, |
| 29 | struct nft_data data[NFT_REG_MAX + 1], |
| 30 | const struct nft_pktinfo *pkt) |
| 31 | { |
| 32 | const struct nft_lookup *priv = nft_expr_priv(expr); |
| 33 | const struct nft_set *set = priv->set; |
| 34 | |
| 35 | if (set->ops->lookup(set, &data[priv->sreg], &data[priv->dreg])) |
| 36 | return; |
| 37 | data[NFT_REG_VERDICT].verdict = NFT_BREAK; |
| 38 | } |
| 39 | |
| 40 | static const struct nla_policy nft_lookup_policy[NFTA_LOOKUP_MAX + 1] = { |
| 41 | [NFTA_LOOKUP_SET] = { .type = NLA_STRING }, |
| 42 | [NFTA_LOOKUP_SREG] = { .type = NLA_U32 }, |
| 43 | [NFTA_LOOKUP_DREG] = { .type = NLA_U32 }, |
| 44 | }; |
| 45 | |
| 46 | static int nft_lookup_init(const struct nft_ctx *ctx, |
| 47 | const struct nft_expr *expr, |
| 48 | const struct nlattr * const tb[]) |
| 49 | { |
| 50 | struct nft_lookup *priv = nft_expr_priv(expr); |
| 51 | struct nft_set *set; |
| 52 | int err; |
| 53 | |
| 54 | if (tb[NFTA_LOOKUP_SET] == NULL || |
| 55 | tb[NFTA_LOOKUP_SREG] == NULL) |
| 56 | return -EINVAL; |
| 57 | |
| 58 | set = nf_tables_set_lookup(ctx->table, tb[NFTA_LOOKUP_SET]); |
| 59 | if (IS_ERR(set)) |
| 60 | return PTR_ERR(set); |
| 61 | |
| 62 | priv->sreg = ntohl(nla_get_be32(tb[NFTA_LOOKUP_SREG])); |
| 63 | err = nft_validate_input_register(priv->sreg); |
| 64 | if (err < 0) |
| 65 | return err; |
| 66 | |
| 67 | if (tb[NFTA_LOOKUP_DREG] != NULL) { |
| 68 | if (!(set->flags & NFT_SET_MAP)) |
| 69 | return -EINVAL; |
| 70 | |
| 71 | priv->dreg = ntohl(nla_get_be32(tb[NFTA_LOOKUP_DREG])); |
| 72 | err = nft_validate_output_register(priv->dreg); |
| 73 | if (err < 0) |
| 74 | return err; |
| 75 | |
| 76 | if (priv->dreg == NFT_REG_VERDICT) { |
| 77 | if (set->dtype != NFT_DATA_VERDICT) |
| 78 | return -EINVAL; |
| 79 | } else if (set->dtype == NFT_DATA_VERDICT) |
| 80 | return -EINVAL; |
| 81 | } else if (set->flags & NFT_SET_MAP) |
| 82 | return -EINVAL; |
| 83 | |
| 84 | err = nf_tables_bind_set(ctx, set, &priv->binding); |
| 85 | if (err < 0) |
| 86 | return err; |
| 87 | |
| 88 | priv->set = set; |
| 89 | return 0; |
| 90 | } |
| 91 | |
| 92 | static void nft_lookup_destroy(const struct nft_expr *expr) |
| 93 | { |
| 94 | struct nft_lookup *priv = nft_expr_priv(expr); |
| 95 | |
| 96 | nf_tables_unbind_set(NULL, priv->set, &priv->binding); |
| 97 | } |
| 98 | |
| 99 | static int nft_lookup_dump(struct sk_buff *skb, const struct nft_expr *expr) |
| 100 | { |
| 101 | const struct nft_lookup *priv = nft_expr_priv(expr); |
| 102 | |
| 103 | if (nla_put_string(skb, NFTA_LOOKUP_SET, priv->set->name)) |
| 104 | goto nla_put_failure; |
| 105 | if (nla_put_be32(skb, NFTA_LOOKUP_SREG, htonl(priv->sreg))) |
| 106 | goto nla_put_failure; |
| 107 | if (priv->set->flags & NFT_SET_MAP) |
| 108 | if (nla_put_be32(skb, NFTA_LOOKUP_DREG, htonl(priv->dreg))) |
| 109 | goto nla_put_failure; |
| 110 | return 0; |
| 111 | |
| 112 | nla_put_failure: |
| 113 | return -1; |
| 114 | } |
| 115 | |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 116 | static struct nft_expr_type nft_lookup_type; |
| 117 | static const struct nft_expr_ops nft_lookup_ops = { |
| 118 | .type = &nft_lookup_type, |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 119 | .size = NFT_EXPR_SIZE(sizeof(struct nft_lookup)), |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 120 | .eval = nft_lookup_eval, |
| 121 | .init = nft_lookup_init, |
| 122 | .destroy = nft_lookup_destroy, |
| 123 | .dump = nft_lookup_dump, |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 124 | }; |
| 125 | |
| 126 | static struct nft_expr_type nft_lookup_type __read_mostly = { |
| 127 | .name = "lookup", |
| 128 | .ops = &nft_lookup_ops, |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 129 | .policy = nft_lookup_policy, |
| 130 | .maxattr = NFTA_LOOKUP_MAX, |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 131 | .owner = THIS_MODULE, |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 132 | }; |
| 133 | |
| 134 | int __init nft_lookup_module_init(void) |
| 135 | { |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 136 | return nft_register_expr(&nft_lookup_type); |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 137 | } |
| 138 | |
| 139 | void nft_lookup_module_exit(void) |
| 140 | { |
Patrick McHardy | ef1f7df | 2013-10-10 11:41:20 +0200 | [diff] [blame] | 141 | nft_unregister_expr(&nft_lookup_type); |
Patrick McHardy | 20a6934 | 2013-10-11 12:06:22 +0200 | [diff] [blame] | 142 | } |