2 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
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.
8 * Development of this code funded by Astaro AG (http://www.astaro.com/)
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/netlink.h>
15 #include <linux/netfilter.h>
16 #include <linux/netfilter/nf_tables.h>
17 #include <net/netfilter/nf_tables_core.h>
18 #include <net/netfilter/nf_tables.h>
22 enum nft_registers sreg:8;
24 enum nft_cmp_ops op:8;
27 static void nft_cmp_eval(const struct nft_expr *expr,
28 struct nft_data data[NFT_REG_MAX + 1],
29 const struct nft_pktinfo *pkt)
31 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
34 d = nft_data_cmp(&data[priv->sreg], &priv->data, priv->len);
62 data[NFT_REG_VERDICT].verdict = NFT_BREAK;
65 static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
66 [NFTA_CMP_SREG] = { .type = NLA_U32 },
67 [NFTA_CMP_OP] = { .type = NLA_U32 },
68 [NFTA_CMP_DATA] = { .type = NLA_NESTED },
71 static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
72 const struct nlattr * const tb[])
74 struct nft_cmp_expr *priv = nft_expr_priv(expr);
75 struct nft_data_desc desc;
78 priv->sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));
79 priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
81 err = nft_data_init(NULL, &priv->data, &desc, tb[NFTA_CMP_DATA]);
88 static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr)
90 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
92 if (nla_put_be32(skb, NFTA_CMP_SREG, htonl(priv->sreg)))
94 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
97 if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
98 NFT_DATA_VALUE, priv->len) < 0)
106 static struct nft_expr_type nft_cmp_type;
107 static const struct nft_expr_ops nft_cmp_ops = {
108 .type = &nft_cmp_type,
109 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
110 .eval = nft_cmp_eval,
111 .init = nft_cmp_init,
112 .dump = nft_cmp_dump,
115 static int nft_cmp_fast_init(const struct nft_ctx *ctx,
116 const struct nft_expr *expr,
117 const struct nlattr * const tb[])
119 struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
120 struct nft_data_desc desc;
121 struct nft_data data;
125 priv->sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));
127 err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
129 desc.len *= BITS_PER_BYTE;
131 mask = ~0U >> (sizeof(priv->data) * BITS_PER_BYTE - desc.len);
132 priv->data = data.data[0] & mask;
133 priv->len = desc.len;
137 static int nft_cmp_fast_dump(struct sk_buff *skb, const struct nft_expr *expr)
139 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
140 struct nft_data data;
142 if (nla_put_be32(skb, NFTA_CMP_SREG, htonl(priv->sreg)))
143 goto nla_put_failure;
144 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(NFT_CMP_EQ)))
145 goto nla_put_failure;
147 data.data[0] = priv->data;
148 if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
149 NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
150 goto nla_put_failure;
157 const struct nft_expr_ops nft_cmp_fast_ops = {
158 .type = &nft_cmp_type,
159 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
160 .eval = NULL, /* inlined */
161 .init = nft_cmp_fast_init,
162 .dump = nft_cmp_fast_dump,
165 static const struct nft_expr_ops *nft_cmp_select_ops(const struct nlattr * const tb[])
167 struct nft_data_desc desc;
168 struct nft_data data;
169 enum nft_registers sreg;
173 if (tb[NFTA_CMP_SREG] == NULL ||
174 tb[NFTA_CMP_OP] == NULL ||
175 tb[NFTA_CMP_DATA] == NULL)
176 return ERR_PTR(-EINVAL);
178 sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));
179 err = nft_validate_input_register(sreg);
183 op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
193 return ERR_PTR(-EINVAL);
196 err = nft_data_init(NULL, &data, &desc, tb[NFTA_CMP_DATA]);
200 if (desc.len <= sizeof(u32) && op == NFT_CMP_EQ)
201 return &nft_cmp_fast_ops;
206 static struct nft_expr_type nft_cmp_type __read_mostly = {
208 .select_ops = nft_cmp_select_ops,
209 .policy = nft_cmp_policy,
210 .maxattr = NFTA_CMP_MAX,
211 .owner = THIS_MODULE,
214 int __init nft_cmp_module_init(void)
216 return nft_register_expr(&nft_cmp_type);
219 void nft_cmp_module_exit(void)
221 nft_unregister_expr(&nft_cmp_type);