[mirror_ubuntu-jammy-kernel.git] / net / netfilter / nft_socket.c

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/module.h>
#include <linux/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_tables_core.h>
#include <net/netfilter/nf_socket.h>
#include <net/inet_sock.h>
#include <net/tcp.h>

struct nft_socket {
	enum nft_socket_keys		key:8;
	u8				level;
	union {
		u8			dreg;
	};
};

static void nft_socket_wildcard(const struct nft_pktinfo *pkt,
				struct nft_regs *regs, struct sock *sk,
				u32 *dest)
{
	switch (nft_pf(pkt)) {
	case NFPROTO_IPV4:
		nft_reg_store8(dest, inet_sk(sk)->inet_rcv_saddr == 0);
		break;
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	case NFPROTO_IPV6:
		nft_reg_store8(dest, ipv6_addr_any(&sk->sk_v6_rcv_saddr));
		break;
#endif
	default:
		regs->verdict.code = NFT_BREAK;
		return;
	}
}

#ifdef CONFIG_SOCK_CGROUP_DATA
static noinline bool
nft_sock_get_eval_cgroupv2(u32 *dest, struct sock *sk, const struct nft_pktinfo *pkt, u32 level)
{
	struct cgroup *cgrp;

	if (!sk_fullsock(sk))
		return false;

	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
	if (level > cgrp->level)
		return false;

	memcpy(dest, &cgrp->ancestor_ids[level], sizeof(u64));

	return true;
}
#endif

static void nft_socket_eval(const struct nft_expr *expr,
			    struct nft_regs *regs,
			    const struct nft_pktinfo *pkt)
{
	const struct nft_socket *priv = nft_expr_priv(expr);
	struct sk_buff *skb = pkt->skb;
	struct sock *sk = skb->sk;
	u32 *dest = &regs->data[priv->dreg];

	if (sk && !net_eq(nft_net(pkt), sock_net(sk)))
		sk = NULL;

	if (!sk)
		switch(nft_pf(pkt)) {
		case NFPROTO_IPV4:
			sk = nf_sk_lookup_slow_v4(nft_net(pkt), skb, nft_in(pkt));
			break;
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
		case NFPROTO_IPV6:
			sk = nf_sk_lookup_slow_v6(nft_net(pkt), skb, nft_in(pkt));
			break;
#endif
		default:
			WARN_ON_ONCE(1);
			regs->verdict.code = NFT_BREAK;
			return;
		}

	if (!sk) {
		regs->verdict.code = NFT_BREAK;
		return;
	}

	switch(priv->key) {
	case NFT_SOCKET_TRANSPARENT:
		nft_reg_store8(dest, inet_sk_transparent(sk));
		break;
	case NFT_SOCKET_MARK:
		if (sk_fullsock(sk)) {
			*dest = sk->sk_mark;
		} else {
			regs->verdict.code = NFT_BREAK;
			return;
		}
		break;
	case NFT_SOCKET_WILDCARD:
		if (!sk_fullsock(sk)) {
			regs->verdict.code = NFT_BREAK;
			return;
		}
		nft_socket_wildcard(pkt, regs, sk, dest);
		break;
#ifdef CONFIG_SOCK_CGROUP_DATA
	case NFT_SOCKET_CGROUPV2:
		if (!nft_sock_get_eval_cgroupv2(dest, sk, pkt, priv->level)) {
			regs->verdict.code = NFT_BREAK;
			return;
		}
		break;
#endif
	default:
		WARN_ON(1);
		regs->verdict.code = NFT_BREAK;
	}

	if (sk != skb->sk)
		sock_gen_put(sk);
}

static const struct nla_policy nft_socket_policy[NFTA_SOCKET_MAX + 1] = {
	[NFTA_SOCKET_KEY]		= { .type = NLA_U32 },
	[NFTA_SOCKET_DREG]		= { .type = NLA_U32 },
	[NFTA_SOCKET_LEVEL]		= { .type = NLA_U32 },
};

static int nft_socket_init(const struct nft_ctx *ctx,
			   const struct nft_expr *expr,
			   const struct nlattr * const tb[])
{
	struct nft_socket *priv = nft_expr_priv(expr);
	unsigned int len;

	if (!tb[NFTA_SOCKET_DREG] || !tb[NFTA_SOCKET_KEY])
		return -EINVAL;

	switch(ctx->family) {
	case NFPROTO_IPV4:
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	case NFPROTO_IPV6:
#endif
	case NFPROTO_INET:
		break;
	default:
		return -EOPNOTSUPP;
	}

	priv->key = ntohl(nla_get_u32(tb[NFTA_SOCKET_KEY]));
	switch(priv->key) {
	case NFT_SOCKET_TRANSPARENT:
	case NFT_SOCKET_WILDCARD:
		len = sizeof(u8);
		break;
	case NFT_SOCKET_MARK:
		len = sizeof(u32);
		break;
#ifdef CONFIG_CGROUPS
	case NFT_SOCKET_CGROUPV2: {
		unsigned int level;

		if (!tb[NFTA_SOCKET_LEVEL])
			return -EINVAL;

		level = ntohl(nla_get_u32(tb[NFTA_SOCKET_LEVEL]));
		if (level > 255)
			return -EOPNOTSUPP;

		priv->level = level;
		len = sizeof(u64);
		break;
	}
#endif
	default:
		return -EOPNOTSUPP;
	}

	return nft_parse_register_store(ctx, tb[NFTA_SOCKET_DREG], &priv->dreg,
					NULL, NFT_DATA_VALUE, len);
}

static int nft_socket_dump(struct sk_buff *skb,
			   const struct nft_expr *expr)
{
	const struct nft_socket *priv = nft_expr_priv(expr);

	if (nla_put_u32(skb, NFTA_SOCKET_KEY, htonl(priv->key)))
		return -1;
	if (nft_dump_register(skb, NFTA_SOCKET_DREG, priv->dreg))
		return -1;
	if (priv->key == NFT_SOCKET_CGROUPV2 &&
	    nla_put_u32(skb, NFTA_SOCKET_LEVEL, htonl(priv->level)))
		return -1;
	return 0;
}

static struct nft_expr_type nft_socket_type;
static const struct nft_expr_ops nft_socket_ops = {
	.type		= &nft_socket_type,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_socket)),
	.eval		= nft_socket_eval,
	.init		= nft_socket_init,
	.dump		= nft_socket_dump,
};

static struct nft_expr_type nft_socket_type __read_mostly = {
	.name		= "socket",
	.ops		= &nft_socket_ops,
	.policy		= nft_socket_policy,
	.maxattr	= NFTA_SOCKET_MAX,
	.owner		= THIS_MODULE,
};

static int __init nft_socket_module_init(void)
{
	return nft_register_expr(&nft_socket_type);
}

static void __exit nft_socket_module_exit(void)
{
	nft_unregister_expr(&nft_socket_type);
}

module_init(nft_socket_module_init);
module_exit(nft_socket_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Máté Eckl");
MODULE_DESCRIPTION("nf_tables socket match module");
MODULE_ALIAS_NFT_EXPR("socket");
Commit	Line	Data
554ced0a ME	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>
8d6e5557	8	#include <net/tcp.h>
554ced0a ME	9
	10	struct nft_socket {
	11	enum nft_socket_keys key:8;
e0bb96db	12	u8 level;
554ced0a	13	union {
345023b0	14	u8 dreg;
554ced0a ME	15	};
	16	};
	17
67407a40 BS	18	static void nft_socket_wildcard(const struct nft_pktinfo *pkt,
	19	struct nft_regs regs, struct sock sk,
	20	u32 *dest)
	21	{
	22	switch (nft_pf(pkt)) {
	23	case NFPROTO_IPV4:
	24	nft_reg_store8(dest, inet_sk(sk)->inet_rcv_saddr == 0);
	25	break;
	26	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	27	case NFPROTO_IPV6:
	28	nft_reg_store8(dest, ipv6_addr_any(&sk->sk_v6_rcv_saddr));
	29	break;
	30	#endif
	31	default:
	32	regs->verdict.code = NFT_BREAK;
	33	return;
	34	}
	35	}
	36
7acc0bb4	37	#ifdef CONFIG_SOCK_CGROUP_DATA
e0bb96db	38	static noinline bool
cacb94a5	39	nft_sock_get_eval_cgroupv2(u32 dest, struct sock sk, const struct nft_pktinfo *pkt, u32 level)
e0bb96db	40	{
e0bb96db PNA	41	struct cgroup *cgrp;
e0bb96db PNA	42
cacb94a5	43	if (!sk_fullsock(sk))
e0bb96db PNA	44	return false;
	45
	46	cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
	47	if (level > cgrp->level)
	48	return false;
	49
	50	memcpy(dest, &cgrp->ancestor_ids[level], sizeof(u64));
	51
	52	return true;
	53	}
	54	#endif
	55
554ced0a ME	56	static void nft_socket_eval(const struct nft_expr *expr,
	57	struct nft_regs *regs,
	58	const struct nft_pktinfo *pkt)
	59	{
	60	const struct nft_socket *priv = nft_expr_priv(expr);
	61	struct sk_buff *skb = pkt->skb;
	62	struct sock *sk = skb->sk;
	63	u32 *dest = &regs->data[priv->dreg];
	64
f5646501 FL	65	if (sk && !net_eq(nft_net(pkt), sock_net(sk)))
	66	sk = NULL;
	67
554ced0a ME	68	if (!sk)
	69	switch(nft_pf(pkt)) {
	70	case NFPROTO_IPV4:
	71	sk = nf_sk_lookup_slow_v4(nft_net(pkt), skb, nft_in(pkt));
	72	break;
5d400a49	73	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
554ced0a ME	74	case NFPROTO_IPV6:
	75	sk = nf_sk_lookup_slow_v6(nft_net(pkt), skb, nft_in(pkt));
	76	break;
	77	#endif
	78	default:
	79	WARN_ON_ONCE(1);
	80	regs->verdict.code = NFT_BREAK;
	81	return;
	82	}
	83
f5646501	84	if (!sk) {
365b5a36	85	regs->verdict.code = NFT_BREAK;
554ced0a ME	86	return;
	87	}
	88
554ced0a ME	89	switch(priv->key) {
554ced0a ME	90	case NFT_SOCKET_TRANSPARENT:
8d6e5557	91	nft_reg_store8(dest, inet_sk_transparent(sk));
554ced0a	92	break;
7d25f885 ME	93	case NFT_SOCKET_MARK:
	94	if (sk_fullsock(sk)) {
	95	*dest = sk->sk_mark;
	96	} else {
	97	regs->verdict.code = NFT_BREAK;
	98	return;
	99	}
	100	break;
67407a40 BS	101	case NFT_SOCKET_WILDCARD:
	102	if (!sk_fullsock(sk)) {
	103	regs->verdict.code = NFT_BREAK;
	104	return;
	105	}
	106	nft_socket_wildcard(pkt, regs, sk, dest);
	107	break;
7acc0bb4	108	#ifdef CONFIG_SOCK_CGROUP_DATA
e0bb96db	109	case NFT_SOCKET_CGROUPV2:
cacb94a5	110	if (!nft_sock_get_eval_cgroupv2(dest, sk, pkt, priv->level)) {
e0bb96db PNA	111	regs->verdict.code = NFT_BREAK;
	112	return;
	113	}
	114	break;
	115	#endif
554ced0a ME	116	default:
	117	WARN_ON(1);
	118	regs->verdict.code = NFT_BREAK;
	119	}
039b1f4f FFM	120
	121	if (sk != skb->sk)
	122	sock_gen_put(sk);
554ced0a ME	123	}
	124
	125	static const struct nla_policy nft_socket_policy[NFTA_SOCKET_MAX + 1] = {
	126	[NFTA_SOCKET_KEY] = { .type = NLA_U32 },
	127	[NFTA_SOCKET_DREG] = { .type = NLA_U32 },
e0bb96db	128	[NFTA_SOCKET_LEVEL] = { .type = NLA_U32 },
554ced0a ME	129	};
	130
	131	static int nft_socket_init(const struct nft_ctx *ctx,
	132	const struct nft_expr *expr,
	133	const struct nlattr * const tb[])
	134	{
	135	struct nft_socket *priv = nft_expr_priv(expr);
8a7363f8	136	unsigned int len;
554ced0a ME	137
	138	if (!tb[NFTA_SOCKET_DREG] \|\| !tb[NFTA_SOCKET_KEY])
	139	return -EINVAL;
	140
	141	switch(ctx->family) {
	142	case NFPROTO_IPV4:
5d400a49	143	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
554ced0a ME	144	case NFPROTO_IPV6:
	145	#endif
	146	case NFPROTO_INET:
	147	break;
	148	default:
	149	return -EOPNOTSUPP;
	150	}
	151
	152	priv->key = ntohl(nla_get_u32(tb[NFTA_SOCKET_KEY]));
	153	switch(priv->key) {
	154	case NFT_SOCKET_TRANSPARENT:
67407a40	155	case NFT_SOCKET_WILDCARD:
554ced0a ME	156	len = sizeof(u8);
554ced0a ME	157	break;
7d25f885 ME	158	case NFT_SOCKET_MARK:
	159	len = sizeof(u32);
	160	break;
e0bb96db	161	#ifdef CONFIG_CGROUPS
8a7363f8 AB	162	case NFT_SOCKET_CGROUPV2: {
	163	unsigned int level;
	164
e0bb96db PNA	165	if (!tb[NFTA_SOCKET_LEVEL])
	166	return -EINVAL;
	167
	168	level = ntohl(nla_get_u32(tb[NFTA_SOCKET_LEVEL]));
	169	if (level > 255)
	170	return -EOPNOTSUPP;
	171
	172	priv->level = level;
	173	len = sizeof(u64);
	174	break;
8a7363f8	175	}
e0bb96db	176	#endif
554ced0a ME	177	default:
	178	return -EOPNOTSUPP;
	179	}
	180
345023b0 PNA	181	return nft_parse_register_store(ctx, tb[NFTA_SOCKET_DREG], &priv->dreg,
345023b0 PNA	182	NULL, NFT_DATA_VALUE, len);
554ced0a ME	183	}
	184
	185	static int nft_socket_dump(struct sk_buff *skb,
	186	const struct nft_expr *expr)
	187	{
	188	const struct nft_socket *priv = nft_expr_priv(expr);
	189
	190	if (nla_put_u32(skb, NFTA_SOCKET_KEY, htonl(priv->key)))
	191	return -1;
	192	if (nft_dump_register(skb, NFTA_SOCKET_DREG, priv->dreg))
	193	return -1;
e0bb96db PNA	194	if (priv->key == NFT_SOCKET_CGROUPV2 &&
	195	nla_put_u32(skb, NFTA_SOCKET_LEVEL, htonl(priv->level)))
	196	return -1;
554ced0a ME	197	return 0;
	198	}
	199
	200	static struct nft_expr_type nft_socket_type;
	201	static const struct nft_expr_ops nft_socket_ops = {
	202	.type = &nft_socket_type,
	203	.size = NFT_EXPR_SIZE(sizeof(struct nft_socket)),
	204	.eval = nft_socket_eval,
	205	.init = nft_socket_init,
	206	.dump = nft_socket_dump,
	207	};
	208
	209	static struct nft_expr_type nft_socket_type __read_mostly = {
	210	.name = "socket",
	211	.ops = &nft_socket_ops,
	212	.policy = nft_socket_policy,
	213	.maxattr = NFTA_SOCKET_MAX,
	214	.owner = THIS_MODULE,
	215	};
	216
	217	static int __init nft_socket_module_init(void)
	218	{
	219	return nft_register_expr(&nft_socket_type);
	220	}
	221
	222	static void __exit nft_socket_module_exit(void)
	223	{
	224	nft_unregister_expr(&nft_socket_type);
	225	}
	226
	227	module_init(nft_socket_module_init);
	228	module_exit(nft_socket_module_exit);
	229
	230	MODULE_LICENSE("GPL");
	231	MODULE_AUTHOR("Máté Eckl");
	232	MODULE_DESCRIPTION("nf_tables socket match module");
3fb61eca	233	MODULE_ALIAS_NFT_EXPR("socket");