1 /* SPDX-License-Identifier: GPL-2.0 */
2 #include <linux/module.h>
3 #include <linux/netfilter/nf_tables.h>
4 #include <net/netfilter/nf_tables.h>
5 #include <net/netfilter/nf_tables_core.h>
6 #include <net/netfilter/nf_socket.h>
7 #include <net/inet_sock.h>
11 enum nft_socket_keys key:8;
19 static void nft_socket_wildcard(const struct nft_pktinfo *pkt,
20 struct nft_regs *regs, struct sock *sk,
23 switch (nft_pf(pkt)) {
25 nft_reg_store8(dest, inet_sk(sk)->inet_rcv_saddr == 0);
27 #if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
29 nft_reg_store8(dest, ipv6_addr_any(&sk->sk_v6_rcv_saddr));
33 regs->verdict.code = NFT_BREAK;
38 #ifdef CONFIG_SOCK_CGROUP_DATA
40 nft_sock_get_eval_cgroupv2(u32 *dest, struct sock *sk, const struct nft_pktinfo *pkt, u32 level)
48 cgrp = cgroup_ancestor(sock_cgroup_ptr(&sk->sk_cgrp_data), level);
52 cgid = cgroup_id(cgrp);
53 memcpy(dest, &cgid, sizeof(u64));
58 static struct sock *nft_socket_do_lookup(const struct nft_pktinfo *pkt)
60 const struct net_device *indev = nft_in(pkt);
61 const struct sk_buff *skb = pkt->skb;
62 struct sock *sk = NULL;
67 switch (nft_pf(pkt)) {
69 sk = nf_sk_lookup_slow_v4(nft_net(pkt), skb, indev);
71 #if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
73 sk = nf_sk_lookup_slow_v6(nft_net(pkt), skb, indev);
84 static void nft_socket_eval(const struct nft_expr *expr,
85 struct nft_regs *regs,
86 const struct nft_pktinfo *pkt)
88 const struct nft_socket *priv = nft_expr_priv(expr);
89 struct sk_buff *skb = pkt->skb;
90 struct sock *sk = skb->sk;
91 u32 *dest = ®s->data[priv->dreg];
93 if (sk && !net_eq(nft_net(pkt), sock_net(sk)))
97 sk = nft_socket_do_lookup(pkt);
100 regs->verdict.code = NFT_BREAK;
105 case NFT_SOCKET_TRANSPARENT:
106 nft_reg_store8(dest, inet_sk_transparent(sk));
108 case NFT_SOCKET_MARK:
109 if (sk_fullsock(sk)) {
110 *dest = READ_ONCE(sk->sk_mark);
112 regs->verdict.code = NFT_BREAK;
116 case NFT_SOCKET_WILDCARD:
117 if (!sk_fullsock(sk)) {
118 regs->verdict.code = NFT_BREAK;
121 nft_socket_wildcard(pkt, regs, sk, dest);
123 #ifdef CONFIG_SOCK_CGROUP_DATA
124 case NFT_SOCKET_CGROUPV2:
125 if (!nft_sock_get_eval_cgroupv2(dest, sk, pkt, priv->level)) {
126 regs->verdict.code = NFT_BREAK;
133 regs->verdict.code = NFT_BREAK;
140 static const struct nla_policy nft_socket_policy[NFTA_SOCKET_MAX + 1] = {
141 [NFTA_SOCKET_KEY] = NLA_POLICY_MAX(NLA_BE32, 255),
142 [NFTA_SOCKET_DREG] = { .type = NLA_U32 },
143 [NFTA_SOCKET_LEVEL] = NLA_POLICY_MAX(NLA_BE32, 255),
146 static int nft_socket_init(const struct nft_ctx *ctx,
147 const struct nft_expr *expr,
148 const struct nlattr * const tb[])
150 struct nft_socket *priv = nft_expr_priv(expr);
153 if (!tb[NFTA_SOCKET_DREG] || !tb[NFTA_SOCKET_KEY])
156 switch(ctx->family) {
158 #if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
167 priv->key = ntohl(nla_get_be32(tb[NFTA_SOCKET_KEY]));
169 case NFT_SOCKET_TRANSPARENT:
170 case NFT_SOCKET_WILDCARD:
173 case NFT_SOCKET_MARK:
176 #ifdef CONFIG_CGROUPS
177 case NFT_SOCKET_CGROUPV2: {
180 if (!tb[NFTA_SOCKET_LEVEL])
183 level = ntohl(nla_get_be32(tb[NFTA_SOCKET_LEVEL]));
197 return nft_parse_register_store(ctx, tb[NFTA_SOCKET_DREG], &priv->dreg,
198 NULL, NFT_DATA_VALUE, len);
201 static int nft_socket_dump(struct sk_buff *skb,
202 const struct nft_expr *expr, bool reset)
204 const struct nft_socket *priv = nft_expr_priv(expr);
206 if (nla_put_be32(skb, NFTA_SOCKET_KEY, htonl(priv->key)))
208 if (nft_dump_register(skb, NFTA_SOCKET_DREG, priv->dreg))
210 if (priv->key == NFT_SOCKET_CGROUPV2 &&
211 nla_put_be32(skb, NFTA_SOCKET_LEVEL, htonl(priv->level)))
216 static bool nft_socket_reduce(struct nft_regs_track *track,
217 const struct nft_expr *expr)
219 const struct nft_socket *priv = nft_expr_priv(expr);
220 const struct nft_socket *socket;
222 if (!nft_reg_track_cmp(track, expr, priv->dreg)) {
223 nft_reg_track_update(track, expr, priv->dreg, priv->len);
227 socket = nft_expr_priv(track->regs[priv->dreg].selector);
228 if (priv->key != socket->key ||
229 priv->dreg != socket->dreg ||
230 priv->level != socket->level) {
231 nft_reg_track_update(track, expr, priv->dreg, priv->len);
235 if (!track->regs[priv->dreg].bitwise)
238 return nft_expr_reduce_bitwise(track, expr);
241 static int nft_socket_validate(const struct nft_ctx *ctx,
242 const struct nft_expr *expr,
243 const struct nft_data **data)
245 if (ctx->family != NFPROTO_IPV4 &&
246 ctx->family != NFPROTO_IPV6 &&
247 ctx->family != NFPROTO_INET)
250 return nft_chain_validate_hooks(ctx->chain,
251 (1 << NF_INET_PRE_ROUTING) |
252 (1 << NF_INET_LOCAL_IN) |
253 (1 << NF_INET_LOCAL_OUT));
256 static struct nft_expr_type nft_socket_type;
257 static const struct nft_expr_ops nft_socket_ops = {
258 .type = &nft_socket_type,
259 .size = NFT_EXPR_SIZE(sizeof(struct nft_socket)),
260 .eval = nft_socket_eval,
261 .init = nft_socket_init,
262 .dump = nft_socket_dump,
263 .validate = nft_socket_validate,
264 .reduce = nft_socket_reduce,
267 static struct nft_expr_type nft_socket_type __read_mostly = {
269 .ops = &nft_socket_ops,
270 .policy = nft_socket_policy,
271 .maxattr = NFTA_SOCKET_MAX,
272 .owner = THIS_MODULE,
275 static int __init nft_socket_module_init(void)
277 return nft_register_expr(&nft_socket_type);
280 static void __exit nft_socket_module_exit(void)
282 nft_unregister_expr(&nft_socket_type);
285 module_init(nft_socket_module_init);
286 module_exit(nft_socket_module_exit);
288 MODULE_LICENSE("GPL");
289 MODULE_AUTHOR("Máté Eckl");
290 MODULE_DESCRIPTION("nf_tables socket match module");
291 MODULE_ALIAS_NFT_EXPR("socket");