1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
5 * Development of this code funded by Astaro AG (http://www.astaro.com/)
8 #include <linux/kernel.h>
9 #include <linux/init.h>
10 #include <linux/module.h>
11 #include <linux/netlink.h>
12 #include <linux/netfilter.h>
13 #include <linux/netfilter/nf_tables.h>
14 #include <net/netfilter/nf_tables_core.h>
15 #include <net/netfilter/nf_tables.h>
19 enum nft_registers sreg:8;
21 enum nft_cmp_ops op:8;
24 void nft_cmp_eval(const struct nft_expr *expr,
25 struct nft_regs *regs,
26 const struct nft_pktinfo *pkt)
28 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
31 d = memcmp(®s->data[priv->sreg], &priv->data, priv->len);
61 regs->verdict.code = NFT_BREAK;
64 static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
65 [NFTA_CMP_SREG] = { .type = NLA_U32 },
66 [NFTA_CMP_OP] = { .type = NLA_U32 },
67 [NFTA_CMP_DATA] = { .type = NLA_NESTED },
70 static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
71 const struct nlattr * const tb[])
73 struct nft_cmp_expr *priv = nft_expr_priv(expr);
74 struct nft_data_desc desc;
77 err = nft_data_init(NULL, &priv->data, sizeof(priv->data), &desc,
82 priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
83 err = nft_validate_register_load(priv->sreg, desc.len);
87 priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
92 static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr)
94 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
96 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
98 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
101 if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
102 NFT_DATA_VALUE, priv->len) < 0)
103 goto nla_put_failure;
110 static const struct nft_expr_ops nft_cmp_ops = {
111 .type = &nft_cmp_type,
112 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
113 .eval = nft_cmp_eval,
114 .init = nft_cmp_init,
115 .dump = nft_cmp_dump,
118 static int nft_cmp_fast_init(const struct nft_ctx *ctx,
119 const struct nft_expr *expr,
120 const struct nlattr * const tb[])
122 struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
123 struct nft_data_desc desc;
124 struct nft_data data;
128 err = nft_data_init(NULL, &data, sizeof(data), &desc,
133 priv->sreg = nft_parse_register(tb[NFTA_CMP_SREG]);
134 err = nft_validate_register_load(priv->sreg, desc.len);
138 desc.len *= BITS_PER_BYTE;
139 mask = nft_cmp_fast_mask(desc.len);
141 priv->data = data.data[0] & mask;
142 priv->len = desc.len;
146 static int nft_cmp_fast_dump(struct sk_buff *skb, const struct nft_expr *expr)
148 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
149 struct nft_data data;
151 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
152 goto nla_put_failure;
153 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(NFT_CMP_EQ)))
154 goto nla_put_failure;
156 data.data[0] = priv->data;
157 if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
158 NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
159 goto nla_put_failure;
166 const struct nft_expr_ops nft_cmp_fast_ops = {
167 .type = &nft_cmp_type,
168 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
169 .eval = NULL, /* inlined */
170 .init = nft_cmp_fast_init,
171 .dump = nft_cmp_fast_dump,
174 static const struct nft_expr_ops *
175 nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
177 struct nft_data_desc desc;
178 struct nft_data data;
182 if (tb[NFTA_CMP_SREG] == NULL ||
183 tb[NFTA_CMP_OP] == NULL ||
184 tb[NFTA_CMP_DATA] == NULL)
185 return ERR_PTR(-EINVAL);
187 op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
197 return ERR_PTR(-EINVAL);
200 err = nft_data_init(NULL, &data, sizeof(data), &desc,
205 if (desc.type != NFT_DATA_VALUE) {
210 if (desc.len <= sizeof(u32) && op == NFT_CMP_EQ)
211 return &nft_cmp_fast_ops;
215 nft_data_release(&data, desc.type);
216 return ERR_PTR(-EINVAL);
219 struct nft_expr_type nft_cmp_type __read_mostly = {
221 .select_ops = nft_cmp_select_ops,
222 .policy = nft_cmp_policy,
223 .maxattr = NFTA_CMP_MAX,
224 .owner = THIS_MODULE,