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>
16 #include <net/netfilter/nf_tables_offload.h>
19 enum nft_registers sreg:8;
20 enum nft_registers dreg:8;
26 void nft_bitwise_eval(const struct nft_expr *expr,
27 struct nft_regs *regs, const struct nft_pktinfo *pkt)
29 const struct nft_bitwise *priv = nft_expr_priv(expr);
30 const u32 *src = ®s->data[priv->sreg];
31 u32 *dst = ®s->data[priv->dreg];
34 for (i = 0; i < DIV_ROUND_UP(priv->len, 4); i++)
35 dst[i] = (src[i] & priv->mask.data[i]) ^ priv->xor.data[i];
38 static const struct nla_policy nft_bitwise_policy[NFTA_BITWISE_MAX + 1] = {
39 [NFTA_BITWISE_SREG] = { .type = NLA_U32 },
40 [NFTA_BITWISE_DREG] = { .type = NLA_U32 },
41 [NFTA_BITWISE_LEN] = { .type = NLA_U32 },
42 [NFTA_BITWISE_MASK] = { .type = NLA_NESTED },
43 [NFTA_BITWISE_XOR] = { .type = NLA_NESTED },
46 static int nft_bitwise_init(const struct nft_ctx *ctx,
47 const struct nft_expr *expr,
48 const struct nlattr * const tb[])
50 struct nft_bitwise *priv = nft_expr_priv(expr);
51 struct nft_data_desc d1, d2;
55 if (tb[NFTA_BITWISE_SREG] == NULL ||
56 tb[NFTA_BITWISE_DREG] == NULL ||
57 tb[NFTA_BITWISE_LEN] == NULL ||
58 tb[NFTA_BITWISE_MASK] == NULL ||
59 tb[NFTA_BITWISE_XOR] == NULL)
62 err = nft_parse_u32_check(tb[NFTA_BITWISE_LEN], U8_MAX, &len);
68 priv->sreg = nft_parse_register(tb[NFTA_BITWISE_SREG]);
69 err = nft_validate_register_load(priv->sreg, priv->len);
73 priv->dreg = nft_parse_register(tb[NFTA_BITWISE_DREG]);
74 err = nft_validate_register_store(ctx, priv->dreg, NULL,
75 NFT_DATA_VALUE, priv->len);
79 err = nft_data_init(NULL, &priv->mask, sizeof(priv->mask), &d1,
80 tb[NFTA_BITWISE_MASK]);
83 if (d1.len != priv->len) {
88 err = nft_data_init(NULL, &priv->xor, sizeof(priv->xor), &d2,
89 tb[NFTA_BITWISE_XOR]);
92 if (d2.len != priv->len) {
99 nft_data_release(&priv->xor, d2.type);
101 nft_data_release(&priv->mask, d1.type);
105 static int nft_bitwise_dump(struct sk_buff *skb, const struct nft_expr *expr)
107 const struct nft_bitwise *priv = nft_expr_priv(expr);
109 if (nft_dump_register(skb, NFTA_BITWISE_SREG, priv->sreg))
110 goto nla_put_failure;
111 if (nft_dump_register(skb, NFTA_BITWISE_DREG, priv->dreg))
112 goto nla_put_failure;
113 if (nla_put_be32(skb, NFTA_BITWISE_LEN, htonl(priv->len)))
114 goto nla_put_failure;
116 if (nft_data_dump(skb, NFTA_BITWISE_MASK, &priv->mask,
117 NFT_DATA_VALUE, priv->len) < 0)
118 goto nla_put_failure;
120 if (nft_data_dump(skb, NFTA_BITWISE_XOR, &priv->xor,
121 NFT_DATA_VALUE, priv->len) < 0)
122 goto nla_put_failure;
130 static struct nft_data zero;
132 static int nft_bitwise_offload(struct nft_offload_ctx *ctx,
133 struct nft_flow_rule *flow,
134 const struct nft_expr *expr)
136 const struct nft_bitwise *priv = nft_expr_priv(expr);
138 if (memcmp(&priv->xor, &zero, sizeof(priv->xor)) ||
139 priv->sreg != priv->dreg)
142 memcpy(&ctx->regs[priv->dreg].mask, &priv->mask, sizeof(priv->mask));
147 static const struct nft_expr_ops nft_bitwise_ops = {
148 .type = &nft_bitwise_type,
149 .size = NFT_EXPR_SIZE(sizeof(struct nft_bitwise)),
150 .eval = nft_bitwise_eval,
151 .init = nft_bitwise_init,
152 .dump = nft_bitwise_dump,
153 .offload = nft_bitwise_offload,
156 struct nft_expr_type nft_bitwise_type __read_mostly = {
158 .ops = &nft_bitwise_ops,
159 .policy = nft_bitwise_policy,
160 .maxattr = NFTA_BITWISE_MAX,
161 .owner = THIS_MODULE,