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/if_arp.h>
14 #include <linux/netfilter/nf_tables.h>
15 #include <net/netfilter/nf_tables_core.h>
16 #include <net/netfilter/nf_tables_offload.h>
17 #include <net/netfilter/nf_tables.h>
23 enum nft_cmp_ops op:8;
26 void nft_cmp_eval(const struct nft_expr *expr,
27 struct nft_regs *regs,
28 const struct nft_pktinfo *pkt)
30 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
33 d = memcmp(®s->data[priv->sreg], &priv->data, priv->len);
63 regs->verdict.code = NFT_BREAK;
66 static const struct nla_policy nft_cmp_policy[NFTA_CMP_MAX + 1] = {
67 [NFTA_CMP_SREG] = { .type = NLA_U32 },
68 [NFTA_CMP_OP] = { .type = NLA_U32 },
69 [NFTA_CMP_DATA] = { .type = NLA_NESTED },
72 static int nft_cmp_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
73 const struct nlattr * const tb[])
75 struct nft_cmp_expr *priv = nft_expr_priv(expr);
76 struct nft_data_desc desc;
79 err = nft_data_init(NULL, &priv->data, sizeof(priv->data), &desc,
84 if (desc.type != NFT_DATA_VALUE) {
86 nft_data_release(&priv->data, desc.type);
90 err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
94 priv->op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
99 static int nft_cmp_dump(struct sk_buff *skb, const struct nft_expr *expr)
101 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
103 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
104 goto nla_put_failure;
105 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(priv->op)))
106 goto nla_put_failure;
108 if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
109 NFT_DATA_VALUE, priv->len) < 0)
110 goto nla_put_failure;
117 union nft_cmp_offload_data {
123 static void nft_payload_n2h(union nft_cmp_offload_data *data,
124 const u8 *val, u32 len)
128 data->val16 = ntohs(*((u16 *)val));
131 data->val32 = ntohl(*((u32 *)val));
134 data->val64 = be64_to_cpu(*((u64 *)val));
142 static int __nft_cmp_offload(struct nft_offload_ctx *ctx,
143 struct nft_flow_rule *flow,
144 const struct nft_cmp_expr *priv)
146 struct nft_offload_reg *reg = &ctx->regs[priv->sreg];
147 union nft_cmp_offload_data _data, _datamask;
148 u8 *mask = (u8 *)&flow->match.mask;
149 u8 *key = (u8 *)&flow->match.key;
152 if (priv->op != NFT_CMP_EQ || priv->len > reg->len)
155 if (reg->flags & NFT_OFFLOAD_F_NETWORK2HOST) {
156 nft_payload_n2h(&_data, (u8 *)&priv->data, reg->len);
157 nft_payload_n2h(&_datamask, (u8 *)®->mask, reg->len);
159 datamask = (u8 *)&_datamask;
161 data = (u8 *)&priv->data;
162 datamask = (u8 *)®->mask;
165 memcpy(key + reg->offset, data, reg->len);
166 memcpy(mask + reg->offset, datamask, reg->len);
168 flow->match.dissector.used_keys |= BIT(reg->key);
169 flow->match.dissector.offset[reg->key] = reg->base_offset;
171 if (reg->key == FLOW_DISSECTOR_KEY_META &&
172 reg->offset == offsetof(struct nft_flow_key, meta.ingress_iftype) &&
173 nft_reg_load16(priv->data.data) != ARPHRD_ETHER)
176 nft_offload_update_dependency(ctx, &priv->data, reg->len);
181 static int nft_cmp_offload(struct nft_offload_ctx *ctx,
182 struct nft_flow_rule *flow,
183 const struct nft_expr *expr)
185 const struct nft_cmp_expr *priv = nft_expr_priv(expr);
187 return __nft_cmp_offload(ctx, flow, priv);
190 static const struct nft_expr_ops nft_cmp_ops = {
191 .type = &nft_cmp_type,
192 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_expr)),
193 .eval = nft_cmp_eval,
194 .init = nft_cmp_init,
195 .dump = nft_cmp_dump,
196 .reduce = NFT_REDUCE_READONLY,
197 .offload = nft_cmp_offload,
200 static int nft_cmp_fast_init(const struct nft_ctx *ctx,
201 const struct nft_expr *expr,
202 const struct nlattr * const tb[])
204 struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
205 struct nft_data_desc desc;
206 struct nft_data data;
209 err = nft_data_init(NULL, &data, sizeof(data), &desc,
214 err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
218 desc.len *= BITS_PER_BYTE;
220 priv->mask = nft_cmp_fast_mask(desc.len);
221 priv->data = data.data[0] & priv->mask;
222 priv->len = desc.len;
223 priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
227 static int nft_cmp_fast_offload(struct nft_offload_ctx *ctx,
228 struct nft_flow_rule *flow,
229 const struct nft_expr *expr)
231 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
232 struct nft_cmp_expr cmp = {
239 .len = priv->len / BITS_PER_BYTE,
240 .op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
243 return __nft_cmp_offload(ctx, flow, &cmp);
246 static int nft_cmp_fast_dump(struct sk_buff *skb, const struct nft_expr *expr)
248 const struct nft_cmp_fast_expr *priv = nft_expr_priv(expr);
249 enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;
250 struct nft_data data;
252 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
253 goto nla_put_failure;
254 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
255 goto nla_put_failure;
257 data.data[0] = priv->data;
258 if (nft_data_dump(skb, NFTA_CMP_DATA, &data,
259 NFT_DATA_VALUE, priv->len / BITS_PER_BYTE) < 0)
260 goto nla_put_failure;
267 const struct nft_expr_ops nft_cmp_fast_ops = {
268 .type = &nft_cmp_type,
269 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp_fast_expr)),
270 .eval = NULL, /* inlined */
271 .init = nft_cmp_fast_init,
272 .dump = nft_cmp_fast_dump,
273 .reduce = NFT_REDUCE_READONLY,
274 .offload = nft_cmp_fast_offload,
277 static u32 nft_cmp_mask(u32 bitlen)
279 return (__force u32)cpu_to_le32(~0U >> (sizeof(u32) * BITS_PER_BYTE - bitlen));
282 static void nft_cmp16_fast_mask(struct nft_data *data, unsigned int bitlen)
284 int len = bitlen / BITS_PER_BYTE;
285 int i, words = len / sizeof(u32);
287 for (i = 0; i < words; i++) {
288 data->data[i] = 0xffffffff;
289 bitlen -= sizeof(u32) * BITS_PER_BYTE;
292 if (len % sizeof(u32))
293 data->data[i++] = nft_cmp_mask(bitlen);
299 static int nft_cmp16_fast_init(const struct nft_ctx *ctx,
300 const struct nft_expr *expr,
301 const struct nlattr * const tb[])
303 struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
304 struct nft_data_desc desc;
307 err = nft_data_init(NULL, &priv->data, sizeof(priv->data), &desc,
312 err = nft_parse_register_load(tb[NFTA_CMP_SREG], &priv->sreg, desc.len);
316 nft_cmp16_fast_mask(&priv->mask, desc.len * BITS_PER_BYTE);
317 priv->inv = ntohl(nla_get_be32(tb[NFTA_CMP_OP])) != NFT_CMP_EQ;
318 priv->len = desc.len;
323 static int nft_cmp16_fast_offload(struct nft_offload_ctx *ctx,
324 struct nft_flow_rule *flow,
325 const struct nft_expr *expr)
327 const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
328 struct nft_cmp_expr cmp = {
332 .op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ,
335 return __nft_cmp_offload(ctx, flow, &cmp);
338 static int nft_cmp16_fast_dump(struct sk_buff *skb, const struct nft_expr *expr)
340 const struct nft_cmp16_fast_expr *priv = nft_expr_priv(expr);
341 enum nft_cmp_ops op = priv->inv ? NFT_CMP_NEQ : NFT_CMP_EQ;
343 if (nft_dump_register(skb, NFTA_CMP_SREG, priv->sreg))
344 goto nla_put_failure;
345 if (nla_put_be32(skb, NFTA_CMP_OP, htonl(op)))
346 goto nla_put_failure;
348 if (nft_data_dump(skb, NFTA_CMP_DATA, &priv->data,
349 NFT_DATA_VALUE, priv->len) < 0)
350 goto nla_put_failure;
358 const struct nft_expr_ops nft_cmp16_fast_ops = {
359 .type = &nft_cmp_type,
360 .size = NFT_EXPR_SIZE(sizeof(struct nft_cmp16_fast_expr)),
361 .eval = NULL, /* inlined */
362 .init = nft_cmp16_fast_init,
363 .dump = nft_cmp16_fast_dump,
364 .reduce = NFT_REDUCE_READONLY,
365 .offload = nft_cmp16_fast_offload,
368 static const struct nft_expr_ops *
369 nft_cmp_select_ops(const struct nft_ctx *ctx, const struct nlattr * const tb[])
371 struct nft_data_desc desc;
372 struct nft_data data;
377 if (tb[NFTA_CMP_SREG] == NULL ||
378 tb[NFTA_CMP_OP] == NULL ||
379 tb[NFTA_CMP_DATA] == NULL)
380 return ERR_PTR(-EINVAL);
382 op = ntohl(nla_get_be32(tb[NFTA_CMP_OP]));
392 return ERR_PTR(-EINVAL);
395 err = nft_data_init(NULL, &data, sizeof(data), &desc,
400 if (desc.type != NFT_DATA_VALUE)
403 sreg = ntohl(nla_get_be32(tb[NFTA_CMP_SREG]));
405 if (op == NFT_CMP_EQ || op == NFT_CMP_NEQ) {
406 if (desc.len <= sizeof(u32))
407 return &nft_cmp_fast_ops;
408 else if (desc.len <= sizeof(data) &&
409 ((sreg >= NFT_REG_1 && sreg <= NFT_REG_4) ||
410 (sreg >= NFT_REG32_00 && sreg <= NFT_REG32_12 && sreg % 2 == 0)))
411 return &nft_cmp16_fast_ops;
415 nft_data_release(&data, desc.type);
416 return ERR_PTR(-EINVAL);
419 struct nft_expr_type nft_cmp_type __read_mostly = {
421 .select_ops = nft_cmp_select_ops,
422 .policy = nft_cmp_policy,
423 .maxattr = NFTA_CMP_MAX,
424 .owner = THIS_MODULE,