1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (c) 2008-2009 Patrick McHardy <kaber@trash.net>
4 * Copyright (c) 2012 Pablo Neira Ayuso <pablo@netfilter.org>
5 * Copyright (c) 2012 Intel Corporation
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/skbuff.h>
12 #include <linux/string.h>
13 #include <linux/netlink.h>
14 #include <linux/netfilter.h>
15 #include <linux/netfilter_ipv4.h>
16 #include <linux/netfilter/nfnetlink.h>
17 #include <linux/netfilter/nf_tables.h>
18 #include <net/netfilter/nf_conntrack.h>
19 #include <net/netfilter/nf_nat.h>
20 #include <net/netfilter/nf_tables.h>
28 enum nf_nat_manip_type type:8;
33 static void nft_nat_setup_addr(struct nf_nat_range2 *range,
34 const struct nft_regs *regs,
35 const struct nft_nat *priv)
37 switch (priv->family) {
39 range->min_addr.ip = (__force __be32)
40 regs->data[priv->sreg_addr_min];
41 range->max_addr.ip = (__force __be32)
42 regs->data[priv->sreg_addr_max];
45 memcpy(range->min_addr.ip6, ®s->data[priv->sreg_addr_min],
46 sizeof(range->min_addr.ip6));
47 memcpy(range->max_addr.ip6, ®s->data[priv->sreg_addr_max],
48 sizeof(range->max_addr.ip6));
53 static void nft_nat_setup_proto(struct nf_nat_range2 *range,
54 const struct nft_regs *regs,
55 const struct nft_nat *priv)
57 range->min_proto.all = (__force __be16)
58 nft_reg_load16(®s->data[priv->sreg_proto_min]);
59 range->max_proto.all = (__force __be16)
60 nft_reg_load16(®s->data[priv->sreg_proto_max]);
63 static void nft_nat_setup_netmap(struct nf_nat_range2 *range,
64 const struct nft_pktinfo *pkt,
65 const struct nft_nat *priv)
67 struct sk_buff *skb = pkt->skb;
68 union nf_inet_addr new_addr;
74 if (nft_pf(pkt) == NFPROTO_IPV4) {
75 new_addr.ip = ip_hdr(skb)->saddr;
76 len = sizeof(struct in_addr);
78 new_addr.in6 = ipv6_hdr(skb)->saddr;
79 len = sizeof(struct in6_addr);
83 if (nft_pf(pkt) == NFPROTO_IPV4) {
84 new_addr.ip = ip_hdr(skb)->daddr;
85 len = sizeof(struct in_addr);
87 new_addr.in6 = ipv6_hdr(skb)->daddr;
88 len = sizeof(struct in6_addr);
93 for (i = 0; i < len / sizeof(__be32); i++) {
94 netmask = ~(range->min_addr.ip6[i] ^ range->max_addr.ip6[i]);
95 new_addr.ip6[i] &= ~netmask;
96 new_addr.ip6[i] |= range->min_addr.ip6[i] & netmask;
99 range->min_addr = new_addr;
100 range->max_addr = new_addr;
103 static void nft_nat_eval(const struct nft_expr *expr,
104 struct nft_regs *regs,
105 const struct nft_pktinfo *pkt)
107 const struct nft_nat *priv = nft_expr_priv(expr);
108 enum ip_conntrack_info ctinfo;
109 struct nf_conn *ct = nf_ct_get(pkt->skb, &ctinfo);
110 struct nf_nat_range2 range;
112 memset(&range, 0, sizeof(range));
114 if (priv->sreg_addr_min) {
115 nft_nat_setup_addr(&range, regs, priv);
116 if (priv->flags & NF_NAT_RANGE_NETMAP)
117 nft_nat_setup_netmap(&range, pkt, priv);
120 if (priv->sreg_proto_min)
121 nft_nat_setup_proto(&range, regs, priv);
123 range.flags = priv->flags;
125 regs->verdict.code = nf_nat_setup_info(ct, &range, priv->type);
128 static const struct nla_policy nft_nat_policy[NFTA_NAT_MAX + 1] = {
129 [NFTA_NAT_TYPE] = { .type = NLA_U32 },
130 [NFTA_NAT_FAMILY] = { .type = NLA_U32 },
131 [NFTA_NAT_REG_ADDR_MIN] = { .type = NLA_U32 },
132 [NFTA_NAT_REG_ADDR_MAX] = { .type = NLA_U32 },
133 [NFTA_NAT_REG_PROTO_MIN] = { .type = NLA_U32 },
134 [NFTA_NAT_REG_PROTO_MAX] = { .type = NLA_U32 },
135 [NFTA_NAT_FLAGS] = { .type = NLA_U32 },
138 static int nft_nat_validate(const struct nft_ctx *ctx,
139 const struct nft_expr *expr,
140 const struct nft_data **data)
142 struct nft_nat *priv = nft_expr_priv(expr);
145 err = nft_chain_validate_dependency(ctx->chain, NFT_CHAIN_T_NAT);
149 switch (priv->type) {
151 err = nft_chain_validate_hooks(ctx->chain,
152 (1 << NF_INET_POST_ROUTING) |
153 (1 << NF_INET_LOCAL_IN));
156 err = nft_chain_validate_hooks(ctx->chain,
157 (1 << NF_INET_PRE_ROUTING) |
158 (1 << NF_INET_LOCAL_OUT));
165 static int nft_nat_init(const struct nft_ctx *ctx, const struct nft_expr *expr,
166 const struct nlattr * const tb[])
168 struct nft_nat *priv = nft_expr_priv(expr);
169 unsigned int alen, plen;
173 if (tb[NFTA_NAT_TYPE] == NULL ||
174 (tb[NFTA_NAT_REG_ADDR_MIN] == NULL &&
175 tb[NFTA_NAT_REG_PROTO_MIN] == NULL))
178 switch (ntohl(nla_get_be32(tb[NFTA_NAT_TYPE]))) {
180 priv->type = NF_NAT_MANIP_SRC;
183 priv->type = NF_NAT_MANIP_DST;
189 if (tb[NFTA_NAT_FAMILY] == NULL)
192 family = ntohl(nla_get_be32(tb[NFTA_NAT_FAMILY]));
193 if (ctx->family != NFPROTO_INET && ctx->family != family)
198 alen = sizeof_field(struct nf_nat_range, min_addr.ip);
201 alen = sizeof_field(struct nf_nat_range, min_addr.ip6);
204 return -EAFNOSUPPORT;
206 priv->family = family;
208 if (tb[NFTA_NAT_REG_ADDR_MIN]) {
209 err = nft_parse_register_load(tb[NFTA_NAT_REG_ADDR_MIN],
210 &priv->sreg_addr_min, alen);
214 if (tb[NFTA_NAT_REG_ADDR_MAX]) {
215 err = nft_parse_register_load(tb[NFTA_NAT_REG_ADDR_MAX],
216 &priv->sreg_addr_max,
221 priv->sreg_addr_max = priv->sreg_addr_min;
224 priv->flags |= NF_NAT_RANGE_MAP_IPS;
227 plen = sizeof_field(struct nf_nat_range, min_addr.all);
228 if (tb[NFTA_NAT_REG_PROTO_MIN]) {
229 err = nft_parse_register_load(tb[NFTA_NAT_REG_PROTO_MIN],
230 &priv->sreg_proto_min, plen);
234 if (tb[NFTA_NAT_REG_PROTO_MAX]) {
235 err = nft_parse_register_load(tb[NFTA_NAT_REG_PROTO_MAX],
236 &priv->sreg_proto_max,
241 priv->sreg_proto_max = priv->sreg_proto_min;
244 priv->flags |= NF_NAT_RANGE_PROTO_SPECIFIED;
247 if (tb[NFTA_NAT_FLAGS]) {
248 priv->flags |= ntohl(nla_get_be32(tb[NFTA_NAT_FLAGS]));
249 if (priv->flags & ~NF_NAT_RANGE_MASK)
253 return nf_ct_netns_get(ctx->net, family);
256 static int nft_nat_dump(struct sk_buff *skb, const struct nft_expr *expr)
258 const struct nft_nat *priv = nft_expr_priv(expr);
260 switch (priv->type) {
261 case NF_NAT_MANIP_SRC:
262 if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_SNAT)))
263 goto nla_put_failure;
265 case NF_NAT_MANIP_DST:
266 if (nla_put_be32(skb, NFTA_NAT_TYPE, htonl(NFT_NAT_DNAT)))
267 goto nla_put_failure;
271 if (nla_put_be32(skb, NFTA_NAT_FAMILY, htonl(priv->family)))
272 goto nla_put_failure;
274 if (priv->sreg_addr_min) {
275 if (nft_dump_register(skb, NFTA_NAT_REG_ADDR_MIN,
276 priv->sreg_addr_min) ||
277 nft_dump_register(skb, NFTA_NAT_REG_ADDR_MAX,
278 priv->sreg_addr_max))
279 goto nla_put_failure;
282 if (priv->sreg_proto_min) {
283 if (nft_dump_register(skb, NFTA_NAT_REG_PROTO_MIN,
284 priv->sreg_proto_min) ||
285 nft_dump_register(skb, NFTA_NAT_REG_PROTO_MAX,
286 priv->sreg_proto_max))
287 goto nla_put_failure;
290 if (priv->flags != 0) {
291 if (nla_put_be32(skb, NFTA_NAT_FLAGS, htonl(priv->flags)))
292 goto nla_put_failure;
302 nft_nat_destroy(const struct nft_ctx *ctx, const struct nft_expr *expr)
304 const struct nft_nat *priv = nft_expr_priv(expr);
306 nf_ct_netns_put(ctx->net, priv->family);
309 static struct nft_expr_type nft_nat_type;
310 static const struct nft_expr_ops nft_nat_ops = {
311 .type = &nft_nat_type,
312 .size = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
313 .eval = nft_nat_eval,
314 .init = nft_nat_init,
315 .destroy = nft_nat_destroy,
316 .dump = nft_nat_dump,
317 .validate = nft_nat_validate,
320 static struct nft_expr_type nft_nat_type __read_mostly = {
323 .policy = nft_nat_policy,
324 .maxattr = NFTA_NAT_MAX,
325 .owner = THIS_MODULE,
328 #ifdef CONFIG_NF_TABLES_INET
329 static void nft_nat_inet_eval(const struct nft_expr *expr,
330 struct nft_regs *regs,
331 const struct nft_pktinfo *pkt)
333 const struct nft_nat *priv = nft_expr_priv(expr);
335 if (priv->family == nft_pf(pkt))
336 nft_nat_eval(expr, regs, pkt);
339 static const struct nft_expr_ops nft_nat_inet_ops = {
340 .type = &nft_nat_type,
341 .size = NFT_EXPR_SIZE(sizeof(struct nft_nat)),
342 .eval = nft_nat_inet_eval,
343 .init = nft_nat_init,
344 .destroy = nft_nat_destroy,
345 .dump = nft_nat_dump,
346 .validate = nft_nat_validate,
349 static struct nft_expr_type nft_inet_nat_type __read_mostly = {
351 .family = NFPROTO_INET,
352 .ops = &nft_nat_inet_ops,
353 .policy = nft_nat_policy,
354 .maxattr = NFTA_NAT_MAX,
355 .owner = THIS_MODULE,
358 static int nft_nat_inet_module_init(void)
360 return nft_register_expr(&nft_inet_nat_type);
363 static void nft_nat_inet_module_exit(void)
365 nft_unregister_expr(&nft_inet_nat_type);
368 static int nft_nat_inet_module_init(void) { return 0; }
369 static void nft_nat_inet_module_exit(void) { }
372 static int __init nft_nat_module_init(void)
374 int ret = nft_nat_inet_module_init();
379 ret = nft_register_expr(&nft_nat_type);
381 nft_nat_inet_module_exit();
386 static void __exit nft_nat_module_exit(void)
388 nft_nat_inet_module_exit();
389 nft_unregister_expr(&nft_nat_type);
392 module_init(nft_nat_module_init);
393 module_exit(nft_nat_module_exit);
395 MODULE_LICENSE("GPL");
396 MODULE_AUTHOR("Tomasz Bursztyka <tomasz.bursztyka@linux.intel.com>");
397 MODULE_ALIAS_NFT_EXPR("nat");
398 MODULE_DESCRIPTION("Network Address Translation support");