[linux-block.git] / net / netfilter / nft_synproxy.c

// SPDX-License-Identifier: GPL-2.0
#include <linux/types.h>
#include <net/ip.h>
#include <net/tcp.h>
#include <net/netlink.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_synproxy.h>
#include <net/netfilter/nf_synproxy.h>
#include <linux/netfilter/nf_tables.h>
#include <linux/netfilter/nf_synproxy.h>

struct nft_synproxy {
	struct nf_synproxy_info	info;
};

static const struct nla_policy nft_synproxy_policy[NFTA_SYNPROXY_MAX + 1] = {
	[NFTA_SYNPROXY_MSS]		= { .type = NLA_U16 },
	[NFTA_SYNPROXY_WSCALE]		= { .type = NLA_U8 },
	[NFTA_SYNPROXY_FLAGS]		= { .type = NLA_U32 },
};

static void nft_synproxy_tcp_options(struct synproxy_options *opts,
				     const struct tcphdr *tcp,
				     struct synproxy_net *snet,
				     struct nf_synproxy_info *info,
				     const struct nft_synproxy *priv)
{
	this_cpu_inc(snet->stats->syn_received);
	if (tcp->ece && tcp->cwr)
		opts->options |= NF_SYNPROXY_OPT_ECN;

	opts->options &= priv->info.options;
	opts->mss_encode = opts->mss_option;
	opts->mss_option = info->mss;
	if (opts->options & NF_SYNPROXY_OPT_TIMESTAMP)
		synproxy_init_timestamp_cookie(info, opts);
	else
		opts->options &= ~(NF_SYNPROXY_OPT_WSCALE |
				   NF_SYNPROXY_OPT_SACK_PERM |
				   NF_SYNPROXY_OPT_ECN);
}

static void nft_synproxy_eval_v4(const struct nft_synproxy *priv,
				 struct nft_regs *regs,
				 const struct nft_pktinfo *pkt,
				 const struct tcphdr *tcp,
				 struct tcphdr *_tcph,
				 struct synproxy_options *opts)
{
	struct nf_synproxy_info info = priv->info;
	struct net *net = nft_net(pkt);
	struct synproxy_net *snet = synproxy_pernet(net);
	struct sk_buff *skb = pkt->skb;

	if (tcp->syn) {
		/* Initial SYN from client */
		nft_synproxy_tcp_options(opts, tcp, snet, &info, priv);
		synproxy_send_client_synack(net, skb, tcp, opts);
		consume_skb(skb);
		regs->verdict.code = NF_STOLEN;
	} else if (tcp->ack) {
		/* ACK from client */
		if (synproxy_recv_client_ack(net, skb, tcp, opts,
					     ntohl(tcp->seq))) {
			consume_skb(skb);
			regs->verdict.code = NF_STOLEN;
		} else {
			regs->verdict.code = NF_DROP;
		}
	}
}

#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
static void nft_synproxy_eval_v6(const struct nft_synproxy *priv,
				 struct nft_regs *regs,
				 const struct nft_pktinfo *pkt,
				 const struct tcphdr *tcp,
				 struct tcphdr *_tcph,
				 struct synproxy_options *opts)
{
	struct nf_synproxy_info info = priv->info;
	struct net *net = nft_net(pkt);
	struct synproxy_net *snet = synproxy_pernet(net);
	struct sk_buff *skb = pkt->skb;

	if (tcp->syn) {
		/* Initial SYN from client */
		nft_synproxy_tcp_options(opts, tcp, snet, &info, priv);
		synproxy_send_client_synack_ipv6(net, skb, tcp, opts);
		consume_skb(skb);
		regs->verdict.code = NF_STOLEN;
	} else if (tcp->ack) {
		/* ACK from client */
		if (synproxy_recv_client_ack_ipv6(net, skb, tcp, opts,
						  ntohl(tcp->seq))) {
			consume_skb(skb);
			regs->verdict.code = NF_STOLEN;
		} else {
			regs->verdict.code = NF_DROP;
		}
	}
}
#endif /* CONFIG_NF_TABLES_IPV6*/

static void nft_synproxy_do_eval(const struct nft_synproxy *priv,
				 struct nft_regs *regs,
				 const struct nft_pktinfo *pkt)
{
	struct synproxy_options opts = {};
	struct sk_buff *skb = pkt->skb;
	int thoff = nft_thoff(pkt);
	const struct tcphdr *tcp;
	struct tcphdr _tcph;

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

	if (nf_ip_checksum(skb, nft_hook(pkt), thoff, IPPROTO_TCP)) {
		regs->verdict.code = NF_DROP;
		return;
	}

	tcp = skb_header_pointer(skb, thoff,
				 sizeof(struct tcphdr),
				 &_tcph);
	if (!tcp) {
		regs->verdict.code = NF_DROP;
		return;
	}

	if (!synproxy_parse_options(skb, thoff, tcp, &opts)) {
		regs->verdict.code = NF_DROP;
		return;
	}

	switch (skb->protocol) {
	case htons(ETH_P_IP):
		nft_synproxy_eval_v4(priv, regs, pkt, tcp, &_tcph, &opts);
		return;
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	case htons(ETH_P_IPV6):
		nft_synproxy_eval_v6(priv, regs, pkt, tcp, &_tcph, &opts);
		return;
#endif
	}
	regs->verdict.code = NFT_BREAK;
}

static int nft_synproxy_do_init(const struct nft_ctx *ctx,
				const struct nlattr * const tb[],
				struct nft_synproxy *priv)
{
	struct synproxy_net *snet = synproxy_pernet(ctx->net);
	u32 flags;
	int err;

	if (tb[NFTA_SYNPROXY_MSS])
		priv->info.mss = ntohs(nla_get_be16(tb[NFTA_SYNPROXY_MSS]));
	if (tb[NFTA_SYNPROXY_WSCALE])
		priv->info.wscale = nla_get_u8(tb[NFTA_SYNPROXY_WSCALE]);
	if (tb[NFTA_SYNPROXY_FLAGS]) {
		flags = ntohl(nla_get_be32(tb[NFTA_SYNPROXY_FLAGS]));
		if (flags & ~NF_SYNPROXY_OPT_MASK)
			return -EOPNOTSUPP;
		priv->info.options = flags;
	}

	err = nf_ct_netns_get(ctx->net, ctx->family);
	if (err)
		return err;

	switch (ctx->family) {
	case NFPROTO_IPV4:
		err = nf_synproxy_ipv4_init(snet, ctx->net);
		if (err)
			goto nf_ct_failure;
		break;
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	case NFPROTO_IPV6:
		err = nf_synproxy_ipv6_init(snet, ctx->net);
		if (err)
			goto nf_ct_failure;
		break;
#endif
	case NFPROTO_INET:
	case NFPROTO_BRIDGE:
		err = nf_synproxy_ipv4_init(snet, ctx->net);
		if (err)
			goto nf_ct_failure;
		err = nf_synproxy_ipv6_init(snet, ctx->net);
		if (err) {
			nf_synproxy_ipv4_fini(snet, ctx->net);
			goto nf_ct_failure;
		}
		break;
	}

	return 0;

nf_ct_failure:
	nf_ct_netns_put(ctx->net, ctx->family);
	return err;
}

static void nft_synproxy_do_destroy(const struct nft_ctx *ctx)
{
	struct synproxy_net *snet = synproxy_pernet(ctx->net);

	switch (ctx->family) {
	case NFPROTO_IPV4:
		nf_synproxy_ipv4_fini(snet, ctx->net);
		break;
#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	case NFPROTO_IPV6:
		nf_synproxy_ipv6_fini(snet, ctx->net);
		break;
#endif
	case NFPROTO_INET:
	case NFPROTO_BRIDGE:
		nf_synproxy_ipv4_fini(snet, ctx->net);
		nf_synproxy_ipv6_fini(snet, ctx->net);
		break;
	}
	nf_ct_netns_put(ctx->net, ctx->family);
}

static int nft_synproxy_do_dump(struct sk_buff *skb, struct nft_synproxy *priv)
{
	if (nla_put_be16(skb, NFTA_SYNPROXY_MSS, htons(priv->info.mss)) ||
	    nla_put_u8(skb, NFTA_SYNPROXY_WSCALE, priv->info.wscale) ||
	    nla_put_be32(skb, NFTA_SYNPROXY_FLAGS, htonl(priv->info.options)))
		goto nla_put_failure;

	return 0;

nla_put_failure:
	return -1;
}

static void nft_synproxy_eval(const struct nft_expr *expr,
			      struct nft_regs *regs,
			      const struct nft_pktinfo *pkt)
{
	const struct nft_synproxy *priv = nft_expr_priv(expr);

	nft_synproxy_do_eval(priv, regs, pkt);
}

static int nft_synproxy_validate(const struct nft_ctx *ctx,
				 const struct nft_expr *expr,
				 const struct nft_data **data)
{
	return nft_chain_validate_hooks(ctx->chain, (1 << NF_INET_LOCAL_IN) |
						    (1 << NF_INET_FORWARD));
}

static int nft_synproxy_init(const struct nft_ctx *ctx,
			     const struct nft_expr *expr,
			     const struct nlattr * const tb[])
{
	struct nft_synproxy *priv = nft_expr_priv(expr);

	return nft_synproxy_do_init(ctx, tb, priv);
}

static void nft_synproxy_destroy(const struct nft_ctx *ctx,
				 const struct nft_expr *expr)
{
	nft_synproxy_do_destroy(ctx);
}

static int nft_synproxy_dump(struct sk_buff *skb,
			     const struct nft_expr *expr, bool reset)
{
	struct nft_synproxy *priv = nft_expr_priv(expr);

	return nft_synproxy_do_dump(skb, priv);
}

static struct nft_expr_type nft_synproxy_type;
static const struct nft_expr_ops nft_synproxy_ops = {
	.eval		= nft_synproxy_eval,
	.size		= NFT_EXPR_SIZE(sizeof(struct nft_synproxy)),
	.init		= nft_synproxy_init,
	.destroy	= nft_synproxy_destroy,
	.dump		= nft_synproxy_dump,
	.type		= &nft_synproxy_type,
	.validate	= nft_synproxy_validate,
	.reduce		= NFT_REDUCE_READONLY,
};

static struct nft_expr_type nft_synproxy_type __read_mostly = {
	.ops		= &nft_synproxy_ops,
	.name		= "synproxy",
	.owner		= THIS_MODULE,
	.policy		= nft_synproxy_policy,
	.maxattr	= NFTA_SYNPROXY_MAX,
};

static int nft_synproxy_obj_init(const struct nft_ctx *ctx,
				 const struct nlattr * const tb[],
				 struct nft_object *obj)
{
	struct nft_synproxy *priv = nft_obj_data(obj);

	return nft_synproxy_do_init(ctx, tb, priv);
}

static void nft_synproxy_obj_destroy(const struct nft_ctx *ctx,
				     struct nft_object *obj)
{
	nft_synproxy_do_destroy(ctx);
}

static int nft_synproxy_obj_dump(struct sk_buff *skb,
				 struct nft_object *obj, bool reset)
{
	struct nft_synproxy *priv = nft_obj_data(obj);

	return nft_synproxy_do_dump(skb, priv);
}

static void nft_synproxy_obj_eval(struct nft_object *obj,
				  struct nft_regs *regs,
				  const struct nft_pktinfo *pkt)
{
	const struct nft_synproxy *priv = nft_obj_data(obj);

	nft_synproxy_do_eval(priv, regs, pkt);
}

static void nft_synproxy_obj_update(struct nft_object *obj,
				    struct nft_object *newobj)
{
	struct nft_synproxy *newpriv = nft_obj_data(newobj);
	struct nft_synproxy *priv = nft_obj_data(obj);

	priv->info = newpriv->info;
}

static struct nft_object_type nft_synproxy_obj_type;
static const struct nft_object_ops nft_synproxy_obj_ops = {
	.type		= &nft_synproxy_obj_type,
	.size		= sizeof(struct nft_synproxy),
	.init		= nft_synproxy_obj_init,
	.destroy	= nft_synproxy_obj_destroy,
	.dump		= nft_synproxy_obj_dump,
	.eval		= nft_synproxy_obj_eval,
	.update		= nft_synproxy_obj_update,
};

static struct nft_object_type nft_synproxy_obj_type __read_mostly = {
	.type		= NFT_OBJECT_SYNPROXY,
	.ops		= &nft_synproxy_obj_ops,
	.maxattr	= NFTA_SYNPROXY_MAX,
	.policy		= nft_synproxy_policy,
	.owner		= THIS_MODULE,
};

static int __init nft_synproxy_module_init(void)
{
	int err;

	err = nft_register_obj(&nft_synproxy_obj_type);
	if (err < 0)
		return err;

	err = nft_register_expr(&nft_synproxy_type);
	if (err < 0)
		goto err;

	return 0;

err:
	nft_unregister_obj(&nft_synproxy_obj_type);
	return err;
}

static void __exit nft_synproxy_module_exit(void)
{
	nft_unregister_expr(&nft_synproxy_type);
	nft_unregister_obj(&nft_synproxy_obj_type);
}

module_init(nft_synproxy_module_init);
module_exit(nft_synproxy_module_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Fernando Fernandez <ffmancera@riseup.net>");
MODULE_ALIAS_NFT_EXPR("synproxy");
MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_SYNPROXY);
MODULE_DESCRIPTION("nftables SYNPROXY expression support");
Commit	Line	Data
ad49d86e FFM	1	// SPDX-License-Identifier: GPL-2.0
	2	#include <linux/types.h>
	3	#include <net/ip.h>
	4	#include <net/tcp.h>
	5	#include <net/netlink.h>
	6	#include <net/netfilter/nf_tables.h>
	7	#include <net/netfilter/nf_conntrack.h>
	8	#include <net/netfilter/nf_conntrack_synproxy.h>
	9	#include <net/netfilter/nf_synproxy.h>
	10	#include <linux/netfilter/nf_tables.h>
	11	#include <linux/netfilter/nf_synproxy.h>
	12
	13	struct nft_synproxy {
	14	struct nf_synproxy_info info;
	15	};
	16
	17	static const struct nla_policy nft_synproxy_policy[NFTA_SYNPROXY_MAX + 1] = {
	18	[NFTA_SYNPROXY_MSS] = { .type = NLA_U16 },
	19	[NFTA_SYNPROXY_WSCALE] = { .type = NLA_U8 },
	20	[NFTA_SYNPROXY_FLAGS] = { .type = NLA_U32 },
	21	};
	22
	23	static void nft_synproxy_tcp_options(struct synproxy_options *opts,
	24	const struct tcphdr *tcp,
	25	struct synproxy_net *snet,
	26	struct nf_synproxy_info *info,
ee394f96	27	const struct nft_synproxy *priv)
ad49d86e FFM	28	{
	29	this_cpu_inc(snet->stats->syn_received);
	30	if (tcp->ece && tcp->cwr)
	31	opts->options \|= NF_SYNPROXY_OPT_ECN;
	32
	33	opts->options &= priv->info.options;
8c0bb787 FFM	34	opts->mss_encode = opts->mss_option;
8c0bb787 FFM	35	opts->mss_option = info->mss;
ad49d86e FFM	36	if (opts->options & NF_SYNPROXY_OPT_TIMESTAMP)
	37	synproxy_init_timestamp_cookie(info, opts);
	38	else
	39	opts->options &= ~(NF_SYNPROXY_OPT_WSCALE \|
	40	NF_SYNPROXY_OPT_SACK_PERM \|
	41	NF_SYNPROXY_OPT_ECN);
	42	}
	43
ee394f96	44	static void nft_synproxy_eval_v4(const struct nft_synproxy *priv,
ad49d86e FFM	45	struct nft_regs *regs,
	46	const struct nft_pktinfo *pkt,
	47	const struct tcphdr *tcp,
	48	struct tcphdr *_tcph,
	49	struct synproxy_options *opts)
	50	{
ad49d86e FFM	51	struct nf_synproxy_info info = priv->info;
	52	struct net *net = nft_net(pkt);
	53	struct synproxy_net *snet = synproxy_pernet(net);
	54	struct sk_buff *skb = pkt->skb;
	55
	56	if (tcp->syn) {
	57	/* Initial SYN from client */
	58	nft_synproxy_tcp_options(opts, tcp, snet, &info, priv);
	59	synproxy_send_client_synack(net, skb, tcp, opts);
	60	consume_skb(skb);
	61	regs->verdict.code = NF_STOLEN;
	62	} else if (tcp->ack) {
	63	/* ACK from client */
	64	if (synproxy_recv_client_ack(net, skb, tcp, opts,
	65	ntohl(tcp->seq))) {
	66	consume_skb(skb);
	67	regs->verdict.code = NF_STOLEN;
	68	} else {
	69	regs->verdict.code = NF_DROP;
	70	}
	71	}
	72	}
	73
	74	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
ee394f96	75	static void nft_synproxy_eval_v6(const struct nft_synproxy *priv,
ad49d86e FFM	76	struct nft_regs *regs,
	77	const struct nft_pktinfo *pkt,
	78	const struct tcphdr *tcp,
	79	struct tcphdr *_tcph,
	80	struct synproxy_options *opts)
	81	{
ad49d86e FFM	82	struct nf_synproxy_info info = priv->info;
	83	struct net *net = nft_net(pkt);
	84	struct synproxy_net *snet = synproxy_pernet(net);
	85	struct sk_buff *skb = pkt->skb;
	86
	87	if (tcp->syn) {
	88	/* Initial SYN from client */
	89	nft_synproxy_tcp_options(opts, tcp, snet, &info, priv);
	90	synproxy_send_client_synack_ipv6(net, skb, tcp, opts);
	91	consume_skb(skb);
	92	regs->verdict.code = NF_STOLEN;
	93	} else if (tcp->ack) {
	94	/* ACK from client */
	95	if (synproxy_recv_client_ack_ipv6(net, skb, tcp, opts,
	96	ntohl(tcp->seq))) {
	97	consume_skb(skb);
	98	regs->verdict.code = NF_STOLEN;
	99	} else {
	100	regs->verdict.code = NF_DROP;
	101	}
	102	}
	103	}
	104	#endif /* CONFIG_NF_TABLES_IPV6*/
	105
ee394f96 FFM	106	static void nft_synproxy_do_eval(const struct nft_synproxy *priv,
	107	struct nft_regs *regs,
	108	const struct nft_pktinfo *pkt)
ad49d86e FFM	109	{
	110	struct synproxy_options opts = {};
	111	struct sk_buff *skb = pkt->skb;
2d7b4ace	112	int thoff = nft_thoff(pkt);
ad49d86e FFM	113	const struct tcphdr *tcp;
	114	struct tcphdr _tcph;
	115
	116	if (pkt->tprot != IPPROTO_TCP) {
	117	regs->verdict.code = NFT_BREAK;
	118	return;
	119	}
	120
	121	if (nf_ip_checksum(skb, nft_hook(pkt), thoff, IPPROTO_TCP)) {
	122	regs->verdict.code = NF_DROP;
	123	return;
	124	}
	125
2d7b4ace	126	tcp = skb_header_pointer(skb, thoff,
ad49d86e FFM	127	sizeof(struct tcphdr),
	128	&_tcph);
	129	if (!tcp) {
	130	regs->verdict.code = NF_DROP;
	131	return;
	132	}
	133
	134	if (!synproxy_parse_options(skb, thoff, tcp, &opts)) {
	135	regs->verdict.code = NF_DROP;
	136	return;
	137	}
	138
	139	switch (skb->protocol) {
	140	case htons(ETH_P_IP):
ee394f96	141	nft_synproxy_eval_v4(priv, regs, pkt, tcp, &_tcph, &opts);
ad49d86e FFM	142	return;
	143	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	144	case htons(ETH_P_IPV6):
ee394f96	145	nft_synproxy_eval_v6(priv, regs, pkt, tcp, &_tcph, &opts);
ad49d86e FFM	146	return;
	147	#endif
	148	}
	149	regs->verdict.code = NFT_BREAK;
	150	}
	151
ee394f96 FFM	152	static int nft_synproxy_do_init(const struct nft_ctx *ctx,
	153	const struct nlattr * const tb[],
	154	struct nft_synproxy *priv)
ad49d86e FFM	155	{
ad49d86e FFM	156	struct synproxy_net *snet = synproxy_pernet(ctx->net);
ad49d86e FFM	157	u32 flags;
	158	int err;
	159
	160	if (tb[NFTA_SYNPROXY_MSS])
	161	priv->info.mss = ntohs(nla_get_be16(tb[NFTA_SYNPROXY_MSS]));
	162	if (tb[NFTA_SYNPROXY_WSCALE])
	163	priv->info.wscale = nla_get_u8(tb[NFTA_SYNPROXY_WSCALE]);
	164	if (tb[NFTA_SYNPROXY_FLAGS]) {
	165	flags = ntohl(nla_get_be32(tb[NFTA_SYNPROXY_FLAGS]));
	166	if (flags & ~NF_SYNPROXY_OPT_MASK)
	167	return -EOPNOTSUPP;
	168	priv->info.options = flags;
	169	}
	170
	171	err = nf_ct_netns_get(ctx->net, ctx->family);
	172	if (err)
	173	return err;
	174
	175	switch (ctx->family) {
	176	case NFPROTO_IPV4:
	177	err = nf_synproxy_ipv4_init(snet, ctx->net);
	178	if (err)
	179	goto nf_ct_failure;
	180	break;
	181	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	182	case NFPROTO_IPV6:
	183	err = nf_synproxy_ipv6_init(snet, ctx->net);
	184	if (err)
	185	goto nf_ct_failure;
	186	break;
	187	#endif
	188	case NFPROTO_INET:
	189	case NFPROTO_BRIDGE:
	190	err = nf_synproxy_ipv4_init(snet, ctx->net);
	191	if (err)
	192	goto nf_ct_failure;
	193	err = nf_synproxy_ipv6_init(snet, ctx->net);
2b4e5fb4 PNA	194	if (err) {
2b4e5fb4 PNA	195	nf_synproxy_ipv4_fini(snet, ctx->net);
ad49d86e	196	goto nf_ct_failure;
2b4e5fb4	197	}
ad49d86e FFM	198	break;
	199	}
	200
	201	return 0;
	202
	203	nf_ct_failure:
	204	nf_ct_netns_put(ctx->net, ctx->family);
	205	return err;
	206	}
	207
ee394f96	208	static void nft_synproxy_do_destroy(const struct nft_ctx *ctx)
ad49d86e FFM	209	{
	210	struct synproxy_net *snet = synproxy_pernet(ctx->net);
	211
	212	switch (ctx->family) {
	213	case NFPROTO_IPV4:
	214	nf_synproxy_ipv4_fini(snet, ctx->net);
	215	break;
	216	#if IS_ENABLED(CONFIG_NF_TABLES_IPV6)
	217	case NFPROTO_IPV6:
	218	nf_synproxy_ipv6_fini(snet, ctx->net);
	219	break;
	220	#endif
	221	case NFPROTO_INET:
	222	case NFPROTO_BRIDGE:
	223	nf_synproxy_ipv4_fini(snet, ctx->net);
	224	nf_synproxy_ipv6_fini(snet, ctx->net);
	225	break;
	226	}
	227	nf_ct_netns_put(ctx->net, ctx->family);
	228	}
	229
ee394f96	230	static int nft_synproxy_do_dump(struct sk_buff skb, struct nft_synproxy priv)
ad49d86e	231	{
ad49d86e FFM	232	if (nla_put_be16(skb, NFTA_SYNPROXY_MSS, htons(priv->info.mss)) \|\|
	233	nla_put_u8(skb, NFTA_SYNPROXY_WSCALE, priv->info.wscale) \|\|
	234	nla_put_be32(skb, NFTA_SYNPROXY_FLAGS, htonl(priv->info.options)))
	235	goto nla_put_failure;
	236
	237	return 0;
	238
	239	nla_put_failure:
	240	return -1;
	241	}
	242
ee394f96 FFM	243	static void nft_synproxy_eval(const struct nft_expr *expr,
	244	struct nft_regs *regs,
	245	const struct nft_pktinfo *pkt)
	246	{
	247	const struct nft_synproxy *priv = nft_expr_priv(expr);
	248
	249	nft_synproxy_do_eval(priv, regs, pkt);
	250	}
	251
ad49d86e FFM	252	static int nft_synproxy_validate(const struct nft_ctx *ctx,
	253	const struct nft_expr *expr,
	254	const struct nft_data **data)
	255	{
	256	return nft_chain_validate_hooks(ctx->chain, (1 << NF_INET_LOCAL_IN) \|
	257	(1 << NF_INET_FORWARD));
	258	}
	259
ee394f96 FFM	260	static int nft_synproxy_init(const struct nft_ctx *ctx,
	261	const struct nft_expr *expr,
	262	const struct nlattr * const tb[])
	263	{
	264	struct nft_synproxy *priv = nft_expr_priv(expr);
	265
	266	return nft_synproxy_do_init(ctx, tb, priv);
	267	}
	268
	269	static void nft_synproxy_destroy(const struct nft_ctx *ctx,
	270	const struct nft_expr *expr)
	271	{
	272	nft_synproxy_do_destroy(ctx);
	273	}
	274
7d34aa3e PS	275	static int nft_synproxy_dump(struct sk_buff *skb,
7d34aa3e PS	276	const struct nft_expr *expr, bool reset)
ee394f96 FFM	277	{
	278	struct nft_synproxy *priv = nft_expr_priv(expr);
	279
	280	return nft_synproxy_do_dump(skb, priv);
	281	}
	282
ad49d86e FFM	283	static struct nft_expr_type nft_synproxy_type;
	284	static const struct nft_expr_ops nft_synproxy_ops = {
	285	.eval = nft_synproxy_eval,
	286	.size = NFT_EXPR_SIZE(sizeof(struct nft_synproxy)),
	287	.init = nft_synproxy_init,
	288	.destroy = nft_synproxy_destroy,
	289	.dump = nft_synproxy_dump,
	290	.type = &nft_synproxy_type,
	291	.validate = nft_synproxy_validate,
b2d30654	292	.reduce = NFT_REDUCE_READONLY,
ad49d86e FFM	293	};
	294
	295	static struct nft_expr_type nft_synproxy_type __read_mostly = {
	296	.ops = &nft_synproxy_ops,
	297	.name = "synproxy",
	298	.owner = THIS_MODULE,
	299	.policy = nft_synproxy_policy,
	300	.maxattr = NFTA_SYNPROXY_MAX,
	301	};
	302
ee394f96 FFM	303	static int nft_synproxy_obj_init(const struct nft_ctx *ctx,
	304	const struct nlattr * const tb[],
	305	struct nft_object *obj)
	306	{
	307	struct nft_synproxy *priv = nft_obj_data(obj);
	308
	309	return nft_synproxy_do_init(ctx, tb, priv);
	310	}
	311
	312	static void nft_synproxy_obj_destroy(const struct nft_ctx *ctx,
	313	struct nft_object *obj)
	314	{
	315	nft_synproxy_do_destroy(ctx);
	316	}
	317
	318	static int nft_synproxy_obj_dump(struct sk_buff *skb,
	319	struct nft_object *obj, bool reset)
	320	{
	321	struct nft_synproxy *priv = nft_obj_data(obj);
	322
	323	return nft_synproxy_do_dump(skb, priv);
	324	}
	325
	326	static void nft_synproxy_obj_eval(struct nft_object *obj,
	327	struct nft_regs *regs,
	328	const struct nft_pktinfo *pkt)
	329	{
	330	const struct nft_synproxy *priv = nft_obj_data(obj);
	331
	332	nft_synproxy_do_eval(priv, regs, pkt);
	333	}
	334
	335	static void nft_synproxy_obj_update(struct nft_object *obj,
	336	struct nft_object *newobj)
	337	{
	338	struct nft_synproxy *newpriv = nft_obj_data(newobj);
	339	struct nft_synproxy *priv = nft_obj_data(obj);
	340
	341	priv->info = newpriv->info;
	342	}
	343
	344	static struct nft_object_type nft_synproxy_obj_type;
	345	static const struct nft_object_ops nft_synproxy_obj_ops = {
	346	.type = &nft_synproxy_obj_type,
	347	.size = sizeof(struct nft_synproxy),
	348	.init = nft_synproxy_obj_init,
	349	.destroy = nft_synproxy_obj_destroy,
	350	.dump = nft_synproxy_obj_dump,
	351	.eval = nft_synproxy_obj_eval,
	352	.update = nft_synproxy_obj_update,
	353	};
	354
	355	static struct nft_object_type nft_synproxy_obj_type __read_mostly = {
	356	.type = NFT_OBJECT_SYNPROXY,
	357	.ops = &nft_synproxy_obj_ops,
	358	.maxattr = NFTA_SYNPROXY_MAX,
	359	.policy = nft_synproxy_policy,
	360	.owner = THIS_MODULE,
	361	};
	362
ad49d86e FFM	363	static int __init nft_synproxy_module_init(void)
ad49d86e FFM	364	{
ee394f96 FFM	365	int err;
	366
	367	err = nft_register_obj(&nft_synproxy_obj_type);
	368	if (err < 0)
	369	return err;
	370
	371	err = nft_register_expr(&nft_synproxy_type);
	372	if (err < 0)
	373	goto err;
	374
	375	return 0;
	376
	377	err:
	378	nft_unregister_obj(&nft_synproxy_obj_type);
	379	return err;
ad49d86e FFM	380	}
	381
	382	static void __exit nft_synproxy_module_exit(void)
	383	{
ee394f96 FFM	384	nft_unregister_expr(&nft_synproxy_type);
ee394f96 FFM	385	nft_unregister_obj(&nft_synproxy_obj_type);
ad49d86e FFM	386	}
	387
	388	module_init(nft_synproxy_module_init);
	389	module_exit(nft_synproxy_module_exit);
	390
	391	MODULE_LICENSE("GPL");
	392	MODULE_AUTHOR("Fernando Fernandez <ffmancera@riseup.net>");
	393	MODULE_ALIAS_NFT_EXPR("synproxy");
ee394f96	394	MODULE_ALIAS_NFT_OBJ(NFT_OBJECT_SYNPROXY);
4cacc395	395	MODULE_DESCRIPTION("nftables SYNPROXY expression support");