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_regs *regs,
29 const struct nft_pktinfo *pkt)
31 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
34 d = memcmp(®s->data[priv->sreg], &priv->data, priv->len);
64 regs->verdict.code = NFT_BREAK;
67 static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
68 [NFTA_CMP_SREG] = { .type = NLA_U32 },
69 [NFTA_CMP_OP] = { .type = NLA_U32 },
70 [NFTA_CMP_DATA] = { .type = NLA_NESTED },
73 static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
74 const struct nlattr * const tb[])
76 struct nft_cmp_expr *priv = nft_expr_priv(expr);
77 struct nft_data_desc desc;
80 err = nft_data_init(NULL, &priv->data, sizeof(priv->data), &desc,
85 if (desc.type != NFT_DATA_VALUE) {
87 nft_data_release(&priv->data, desc.type);
91 priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
92 err = nft_validate_register_load(priv->sreg, desc.len);
96 priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
101 static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr)
103 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
105 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
106 goto nla_put_failure;
107 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
108 goto nla_put_failure;
110 if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
111 NFT_DATA_VALUE, priv->len) < 0)
112 goto nla_put_failure;
119 static const struct nft_expr_ops nft_cmp_ops = {
120 .type = &nft_cmp_type,
121 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
122 .eval = nft_cmp_eval,
123 .init = nft_cmp_init,
124 .dump = nft_cmp_dump,
127 static int nft_cmp_fast_init(const struct nft_ctx *ctx,
128 const struct nft_expr *expr,
129 const struct nlattr * const tb[])
131 struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
132 struct nft_data_desc desc;
133 struct nft_data data;
137 err = nft_data_init(NULL, &data, sizeof(data), &desc,
142 priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
143 err = nft_validate_register_load(priv->sreg, desc.len);
147 desc.len *= BITS_PER_BYTE;
148 mask = nft_cmp_fast_mask(desc.len);
150 priv->data = data.data[0] & mask;
151 priv->len = desc.len;
155 static int nft_cmp_fast_dump(struct sk_buff *skb, const struct nft_expr *expr)
157 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
158 struct nft_data data;
160 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
161 goto nla_put_failure;
162 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(NFT_CMP_EQ)))
163 goto nla_put_failure;
165 data.data[0] = priv->data;
166 if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
167 NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
168 goto nla_put_failure;
175 const struct nft_expr_ops nft_cmp_fast_ops = {
176 .type = &nft_cmp_type,
177 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
178 .eval = NULL, /* inlined */
179 .init = nft_cmp_fast_init,
180 .dump = nft_cmp_fast_dump,
183 static const struct nft_expr_ops *
184 nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
186 struct nft_data_desc desc;
187 struct nft_data data;
191 if (tb[NFTA_CMP_SREG] == NULL ||
192 tb[NFTA_CMP_OP] == NULL ||
193 tb[NFTA_CMP_DATA] == NULL)
194 return ERR_PTR(-EINVAL);
196 op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
206 return ERR_PTR(-EINVAL);
209 err = nft_data_init(NULL, &data, sizeof(data), &desc,
214 if (desc.type != NFT_DATA_VALUE) {
219 if (desc.len <= sizeof(u32) && op == NFT_CMP_EQ)
220 return &nft_cmp_fast_ops;
224 nft_data_release(&data, desc.type);
225 return ERR_PTR(-EINVAL);
228 struct nft_expr_type nft_cmp_type __read_mostly = {
230 .select_ops = nft_cmp_select_ops,
231 .policy = nft_cmp_policy,
232 .maxattr = NFTA_CMP_MAX,
233 .owner = THIS_MODULE,