[mirror_ubuntu-hirsute-kernel.git] / net / ipv6 / netfilter / nf_conntrack_l3proto_ipv6.c

/*
 * Copyright (C)2004 USAGI/WIDE Project
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * Author:
 *	Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
 */

#include <linux/types.h>
#include <linux/ipv6.h>
#include <linux/in6.h>
#include <linux/netfilter.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/icmp.h>
#include <net/ipv6.h>
#include <net/inet_frag.h>

#include <linux/netfilter_bridge.h>
#include <linux/netfilter_ipv6.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_l3proto.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/nf_conntrack_seqadj.h>
#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
#include <net/netfilter/nf_nat_helper.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
#include <net/netfilter/nf_log.h>

static int conntrack6_net_id;
static DEFINE_MUTEX(register_ipv6_hooks);

struct conntrack6_net {
	unsigned int users;
};

static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
			      struct nf_conntrack_tuple *tuple)
{
	const u_int32_t *ap;
	u_int32_t _addrs[8];

	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
				sizeof(_addrs), _addrs);
	if (ap == NULL)
		return false;

	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));

	return true;
}

static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
			      const struct nf_conntrack_tuple *orig)
{
	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));

	return true;
}

static void ipv6_print_tuple(struct seq_file *s,
			    const struct nf_conntrack_tuple *tuple)
{
	seq_printf(s, "src=%pI6 dst=%pI6 ",
		   tuple->src.u3.ip6, tuple->dst.u3.ip6);
}

static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
			    unsigned int *dataoff, u_int8_t *protonum)
{
	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
	__be16 frag_off;
	int protoff;
	u8 nexthdr;

	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
			  &nexthdr, sizeof(nexthdr)) != 0) {
		pr_debug("ip6_conntrack_core: can't get nexthdr\n");
		return -NF_ACCEPT;
	}
	protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
	/*
	 * (protoff == skb->len) means the packet has not data, just
	 * IPv6 and possibly extensions headers, but it is tracked anyway
	 */
	if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
		pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
		return -NF_ACCEPT;
	}

	*dataoff = protoff;
	*protonum = nexthdr;
	return NF_ACCEPT;
}

static unsigned int ipv6_helper(void *priv,
				struct sk_buff *skb,
				const struct nf_hook_state *state)
{
	struct nf_conn *ct;
	const struct nf_conn_help *help;
	const struct nf_conntrack_helper *helper;
	enum ip_conntrack_info ctinfo;
	__be16 frag_off;
	int protoff;
	u8 nexthdr;

	/* This is where we call the helper: as the packet goes out. */
	ct = nf_ct_get(skb, &ctinfo);
	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
		return NF_ACCEPT;

	help = nfct_help(ct);
	if (!help)
		return NF_ACCEPT;
	/* rcu_read_lock()ed by nf_hook_thresh */
	helper = rcu_dereference(help->helper);
	if (!helper)
		return NF_ACCEPT;

	nexthdr = ipv6_hdr(skb)->nexthdr;
	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
				   &frag_off);
	if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
		pr_debug("proto header not found\n");
		return NF_ACCEPT;
	}

	return helper->help(skb, protoff, ct, ctinfo);
}

static unsigned int ipv6_confirm(void *priv,
				 struct sk_buff *skb,
				 const struct nf_hook_state *state)
{
	struct nf_conn *ct;
	enum ip_conntrack_info ctinfo;
	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
	int protoff;
	__be16 frag_off;

	ct = nf_ct_get(skb, &ctinfo);
	if (!ct || ctinfo == IP_CT_RELATED_REPLY)
		goto out;

	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
				   &frag_off);
	if (protoff < 0 || (frag_off & htons(~0x7)) != 0) {
		pr_debug("proto header not found\n");
		goto out;
	}

	/* adjust seqs for loopback traffic only in outgoing direction */
	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
	    !nf_is_loopback_packet(skb)) {
		if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
			NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
			return NF_DROP;
		}
	}
out:
	/* We've seen it coming out the other side: confirm it */
	return nf_conntrack_confirm(skb);
}

static unsigned int ipv6_conntrack_in(void *priv,
				      struct sk_buff *skb,
				      const struct nf_hook_state *state)
{
	return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
}

static unsigned int ipv6_conntrack_local(void *priv,
					 struct sk_buff *skb,
					 const struct nf_hook_state *state)
{
	/* root is playing with raw sockets. */
	if (skb->len < sizeof(struct ipv6hdr)) {
		net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
		return NF_ACCEPT;
	}
	return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
}

static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
	{
		.hook		= ipv6_conntrack_in,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_conntrack_local,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK,
	},
	{
		.hook		= ipv6_helper,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_POST_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK_HELPER,
	},
	{
		.hook		= ipv6_confirm,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_POST_ROUTING,
		.priority	= NF_IP6_PRI_LAST,
	},
	{
		.hook		= ipv6_helper,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_IN,
		.priority	= NF_IP6_PRI_CONNTRACK_HELPER,
	},
	{
		.hook		= ipv6_confirm,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_IN,
		.priority	= NF_IP6_PRI_LAST-1,
	},
};

static int
ipv6_getorigdst(struct sock *sk, int optval, void __user *user, int *len)
{
	const struct inet_sock *inet = inet_sk(sk);
	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
	const struct nf_conntrack_tuple_hash *h;
	struct sockaddr_in6 sin6;
	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
	struct nf_conn *ct;

	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
	tuple.src.u.tcp.port = inet->inet_sport;
	tuple.dst.u3.in6 = sk->sk_v6_daddr;
	tuple.dst.u.tcp.port = inet->inet_dport;
	tuple.dst.protonum = sk->sk_protocol;

	if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP)
		return -ENOPROTOOPT;

	if (*len < 0 || (unsigned int) *len < sizeof(sin6))
		return -EINVAL;

	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
	if (!h) {
		pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
			 &tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
			 &tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
		return -ENOENT;
	}

	ct = nf_ct_tuplehash_to_ctrack(h);

	sin6.sin6_family = AF_INET6;
	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
	sin6.sin6_flowinfo = inet6->flow_label & IPV6_FLOWINFO_MASK;
	memcpy(&sin6.sin6_addr,
		&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
					sizeof(sin6.sin6_addr));

	nf_ct_put(ct);
	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr,
						 sk->sk_bound_dev_if);
	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
}

#if IS_ENABLED(CONFIG_NF_CT_NETLINK)

#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nfnetlink_conntrack.h>

static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
				const struct nf_conntrack_tuple *tuple)
{
	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) ||
	    nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
		goto nla_put_failure;
	return 0;

nla_put_failure:
	return -1;
}

static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	[CTA_IP_V6_SRC]	= { .len = sizeof(u_int32_t)*4 },
	[CTA_IP_V6_DST]	= { .len = sizeof(u_int32_t)*4 },
};

static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
				struct nf_conntrack_tuple *t)
{
	if (!tb[CTA_IP_V6_SRC] || !tb[CTA_IP_V6_DST])
		return -EINVAL;

	t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
	t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);

	return 0;
}

static int ipv6_nlattr_tuple_size(void)
{
	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
}
#endif

static int ipv6_hooks_register(struct net *net)
{
	struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);
	int err = 0;

	mutex_lock(&register_ipv6_hooks);
	cnet->users++;
	if (cnet->users > 1)
		goto out_unlock;

	err = nf_defrag_ipv6_enable(net);
	if (err < 0) {
		cnet->users = 0;
		goto out_unlock;
	}

	err = nf_register_net_hooks(net, ipv6_conntrack_ops,
				    ARRAY_SIZE(ipv6_conntrack_ops));
	if (err)
		cnet->users = 0;
 out_unlock:
	mutex_unlock(&register_ipv6_hooks);
	return err;
}

static void ipv6_hooks_unregister(struct net *net)
{
	struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);

	mutex_lock(&register_ipv6_hooks);
	if (cnet->users && (--cnet->users == 0))
		nf_unregister_net_hooks(net, ipv6_conntrack_ops,
					ARRAY_SIZE(ipv6_conntrack_ops));
	mutex_unlock(&register_ipv6_hooks);
}

struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
	.l3proto		= PF_INET6,
	.name			= "ipv6",
	.pkt_to_tuple		= ipv6_pkt_to_tuple,
	.invert_tuple		= ipv6_invert_tuple,
	.print_tuple		= ipv6_print_tuple,
	.get_l4proto		= ipv6_get_l4proto,
#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
	.tuple_to_nlattr	= ipv6_tuple_to_nlattr,
	.nlattr_tuple_size	= ipv6_nlattr_tuple_size,
	.nlattr_to_tuple	= ipv6_nlattr_to_tuple,
	.nla_policy		= ipv6_nla_policy,
#endif
	.net_ns_get		= ipv6_hooks_register,
	.net_ns_put		= ipv6_hooks_unregister,
	.me			= THIS_MODULE,
};

MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");

static struct nf_sockopt_ops so_getorigdst6 = {
	.pf		= NFPROTO_IPV6,
	.get_optmin	= IP6T_SO_ORIGINAL_DST,
	.get_optmax	= IP6T_SO_ORIGINAL_DST + 1,
	.get		= ipv6_getorigdst,
	.owner		= THIS_MODULE,
};

static struct nf_conntrack_l4proto *builtin_l4proto6[] = {
	&nf_conntrack_l4proto_tcp6,
	&nf_conntrack_l4proto_udp6,
	&nf_conntrack_l4proto_icmpv6,
#ifdef CONFIG_NF_CT_PROTO_DCCP
	&nf_conntrack_l4proto_dccp6,
#endif
#ifdef CONFIG_NF_CT_PROTO_SCTP
	&nf_conntrack_l4proto_sctp6,
#endif
#ifdef CONFIG_NF_CT_PROTO_UDPLITE
	&nf_conntrack_l4proto_udplite6,
#endif
};

static int ipv6_net_init(struct net *net)
{
	int ret = 0;

	ret = nf_ct_l4proto_pernet_register(net, builtin_l4proto6,
					    ARRAY_SIZE(builtin_l4proto6));
	if (ret < 0)
		return ret;

	ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
		nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
						ARRAY_SIZE(builtin_l4proto6));
	}
	return ret;
}

static void ipv6_net_exit(struct net *net)
{
	nf_ct_l3proto_pernet_unregister(net, &nf_conntrack_l3proto_ipv6);
	nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
					ARRAY_SIZE(builtin_l4proto6));
}

static struct pernet_operations ipv6_net_ops = {
	.init = ipv6_net_init,
	.exit = ipv6_net_exit,
	.id = &conntrack6_net_id,
	.size = sizeof(struct conntrack6_net),
};

static int __init nf_conntrack_l3proto_ipv6_init(void)
{
	int ret = 0;

	need_conntrack();

	ret = nf_register_sockopt(&so_getorigdst6);
	if (ret < 0) {
		pr_err("Unable to register netfilter socket option\n");
		return ret;
	}

	ret = register_pernet_subsys(&ipv6_net_ops);
	if (ret < 0)
		goto cleanup_sockopt;

	ret = nf_ct_l4proto_register(builtin_l4proto6,
				     ARRAY_SIZE(builtin_l4proto6));
	if (ret < 0)
		goto cleanup_pernet;

	ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: can't register ipv6 proto.\n");
		goto cleanup_l4proto;
	}
	return ret;
cleanup_l4proto:
	nf_ct_l4proto_unregister(builtin_l4proto6,
				 ARRAY_SIZE(builtin_l4proto6));
 cleanup_pernet:
	unregister_pernet_subsys(&ipv6_net_ops);
 cleanup_sockopt:
	nf_unregister_sockopt(&so_getorigdst6);
	return ret;
}

static void __exit nf_conntrack_l3proto_ipv6_fini(void)
{
	synchronize_net();
	nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
	nf_ct_l4proto_unregister(builtin_l4proto6,
				 ARRAY_SIZE(builtin_l4proto6));
	unregister_pernet_subsys(&ipv6_net_ops);
	nf_unregister_sockopt(&so_getorigdst6);
}

module_init(nf_conntrack_l3proto_ipv6_init);
module_exit(nf_conntrack_l3proto_ipv6_fini);
Commit	Line	Data
9fb9cbb1 YK	1	/*
	2	* Copyright (C)2004 USAGI/WIDE Project
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*
	8	* Author:
	9	* Yasuyuki Kozakai @USAGI <yasuyuki.kozakai@toshiba.co.jp>
9fb9cbb1 YK	10	*/
9fb9cbb1 YK	11
9fb9cbb1 YK	12	#include <linux/types.h>
	13	#include <linux/ipv6.h>
	14	#include <linux/in6.h>
	15	#include <linux/netfilter.h>
	16	#include <linux/module.h>
	17	#include <linux/skbuff.h>
	18	#include <linux/icmp.h>
9fb9cbb1	19	#include <net/ipv6.h>
04128f23	20	#include <net/inet_frag.h>
9fb9cbb1	21
8fa9ff68	22	#include <linux/netfilter_bridge.h>
9fb9cbb1	23	#include <linux/netfilter_ipv6.h>
121d1e09	24	#include <linux/netfilter_ipv6/ip6_tables.h>
9fb9cbb1 YK	25	#include <net/netfilter/nf_conntrack.h>
9fb9cbb1 YK	26	#include <net/netfilter/nf_conntrack_helper.h>
605dcad6	27	#include <net/netfilter/nf_conntrack_l4proto.h>
9fb9cbb1 YK	28	#include <net/netfilter/nf_conntrack_l3proto.h>
9fb9cbb1 YK	29	#include <net/netfilter/nf_conntrack_core.h>
5d0aa2cc	30	#include <net/netfilter/nf_conntrack_zones.h>
41d73ec0	31	#include <net/netfilter/nf_conntrack_seqadj.h>
9d2493f8	32	#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
58a317f1	33	#include <net/netfilter/nf_nat_helper.h>
e97c3e27	34	#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
74f7a655	35	#include <net/netfilter/nf_log.h>
9fb9cbb1	36
0c66dc1e FW	37	static int conntrack6_net_id;
	38	static DEFINE_MUTEX(register_ipv6_hooks);
	39
	40	struct conntrack6_net {
	41	unsigned int users;
	42	};
	43
8ce8439a JE	44	static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
8ce8439a JE	45	struct nf_conntrack_tuple *tuple)
9fb9cbb1	46	{
32948588 JE	47	const u_int32_t *ap;
32948588 JE	48	u_int32_t _addrs[8];
9fb9cbb1 YK	49
	50	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	51	sizeof(_addrs), _addrs);
	52	if (ap == NULL)
8ce8439a	53	return false;
9fb9cbb1 YK	54
	55	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	56	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	57
8ce8439a	58	return true;
9fb9cbb1 YK	59	}
9fb9cbb1 YK	60
8ce8439a JE	61	static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
8ce8439a JE	62	const struct nf_conntrack_tuple *orig)
9fb9cbb1 YK	63	{
	64	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	65	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	66
8ce8439a	67	return true;
9fb9cbb1 YK	68	}
9fb9cbb1 YK	69
824f1fbe	70	static void ipv6_print_tuple(struct seq_file *s,
9fb9cbb1 YK	71	const struct nf_conntrack_tuple *tuple)
9fb9cbb1 YK	72	{
824f1fbe JP	73	seq_printf(s, "src=%pI6 dst=%pI6 ",
824f1fbe JP	74	tuple->src.u3.ip6, tuple->dst.u3.ip6);
9fb9cbb1 YK	75	}
9fb9cbb1 YK	76
ffc30690 YK	77	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	78	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	79	{
ffc30690	80	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
2b60af01	81	__be16 frag_off;
ffc30690	82	int protoff;
2b60af01	83	u8 nexthdr;
ffc30690 YK	84
ffc30690 YK	85	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
2b60af01	86	&nexthdr, sizeof(nexthdr)) != 0) {
ffc30690 YK	87	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	88	return -NF_ACCEPT;
	89	}
2b60af01	90	protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
9fb9cbb1	91	/*
d7a769ff FF	92	* (protoff == skb->len) means the packet has not data, just
d7a769ff FF	93	* IPv6 and possibly extensions headers, but it is tracked anyway
9fb9cbb1	94	*/
2b60af01	95	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
0d53778e	96	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	97	return -NF_ACCEPT;
	98	}
	99
	100	*dataoff = protoff;
2b60af01	101	*protonum = nexthdr;
9fb9cbb1 YK	102	return NF_ACCEPT;
	103	}
	104
06198b34	105	static unsigned int ipv6_helper(void *priv,
12f7a505	106	struct sk_buff *skb,
238e54c9	107	const struct nf_hook_state *state)
9fb9cbb1 YK	108	{
9fb9cbb1 YK	109	struct nf_conn *ct;
32948588 JE	110	const struct nf_conn_help *help;
32948588 JE	111	const struct nf_conntrack_helper *helper;
9fb9cbb1	112	enum ip_conntrack_info ctinfo;
4cdd3408 PM	113	__be16 frag_off;
	114	int protoff;
	115	u8 nexthdr;
9fb9cbb1 YK	116
9fb9cbb1 YK	117	/* This is where we call the helper: as the packet goes out. */
3db05fea	118	ct = nf_ct_get(skb, &ctinfo);
fb048833	119	if (!ct \|\| ctinfo == IP_CT_RELATED_REPLY)
12f7a505	120	return NF_ACCEPT;
dc808fe2 HW	121
dc808fe2 HW	122	help = nfct_help(ct);
3c158f7f	123	if (!help)
12f7a505	124	return NF_ACCEPT;
e2361cb9	125	/* rcu_read_lock()ed by nf_hook_thresh */
3c158f7f PM	126	helper = rcu_dereference(help->helper);
3c158f7f PM	127	if (!helper)
12f7a505	128	return NF_ACCEPT;
dc808fe2	129
4cdd3408 PM	130	nexthdr = ipv6_hdr(skb)->nexthdr;
	131	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
	132	&frag_off);
	133	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
0d53778e	134	pr_debug("proto header not found\n");
dc808fe2	135	return NF_ACCEPT;
9fb9cbb1 YK	136	}
9fb9cbb1 YK	137
b20ab9cc	138	return helper->help(skb, protoff, ct, ctinfo);
12f7a505 PNA	139	}
12f7a505 PNA	140
06198b34	141	static unsigned int ipv6_confirm(void *priv,
12f7a505	142	struct sk_buff *skb,
238e54c9	143	const struct nf_hook_state *state)
12f7a505	144	{
58a317f1 PM	145	struct nf_conn *ct;
	146	enum ip_conntrack_info ctinfo;
	147	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
	148	int protoff;
	149	__be16 frag_off;
	150
	151	ct = nf_ct_get(skb, &ctinfo);
	152	if (!ct \|\| ctinfo == IP_CT_RELATED_REPLY)
	153	goto out;
	154
	155	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
	156	&frag_off);
	157	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
	158	pr_debug("proto header not found\n");
	159	goto out;
	160	}
	161
	162	/* adjust seqs for loopback traffic only in outgoing direction */
	163	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
	164	!nf_is_loopback_packet(skb)) {
41d73ec0	165	if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
58a317f1 PM	166	NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
	167	return NF_DROP;
	168	}
	169	}
	170	out:
9fb9cbb1	171	/* We've seen it coming out the other side: confirm it */
3db05fea	172	return nf_conntrack_confirm(skb);
9fb9cbb1 YK	173	}
9fb9cbb1 YK	174
06198b34	175	static unsigned int ipv6_conntrack_in(void *priv,
a702a65f	176	struct sk_buff *skb,
238e54c9	177	const struct nf_hook_state *state)
a702a65f	178	{
082a758f	179	return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
9fb9cbb1 YK	180	}
9fb9cbb1 YK	181
06198b34	182	static unsigned int ipv6_conntrack_local(void *priv,
3db05fea	183	struct sk_buff *skb,
238e54c9	184	const struct nf_hook_state *state)
9fb9cbb1 YK	185	{
9fb9cbb1 YK	186	/* root is playing with raw sockets. */
3db05fea	187	if (skb->len < sizeof(struct ipv6hdr)) {
e87cc472	188	net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
9fb9cbb1 YK	189	return NF_ACCEPT;
9fb9cbb1 YK	190	}
082a758f	191	return nf_conntrack_in(state->net, PF_INET6, state->hook, skb);
9fb9cbb1 YK	192	}
9fb9cbb1 YK	193
1999414a	194	static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
964ddaa1 PM	195	{
964ddaa1 PM	196	.hook = ipv6_conntrack_in,
57750a22	197	.pf = NFPROTO_IPV6,
6e23ae2a	198	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	199	.priority = NF_IP6_PRI_CONNTRACK,
	200	},
	201	{
	202	.hook = ipv6_conntrack_local,
57750a22	203	.pf = NFPROTO_IPV6,
6e23ae2a	204	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	205	.priority = NF_IP6_PRI_CONNTRACK,
964ddaa1 PM	206	},
12f7a505 PNA	207	{
12f7a505 PNA	208	.hook = ipv6_helper,
12f7a505 PNA	209	.pf = NFPROTO_IPV6,
	210	.hooknum = NF_INET_POST_ROUTING,
	211	.priority = NF_IP6_PRI_CONNTRACK_HELPER,
	212	},
964ddaa1 PM	213	{
964ddaa1 PM	214	.hook = ipv6_confirm,
57750a22	215	.pf = NFPROTO_IPV6,
6e23ae2a	216	.hooknum = NF_INET_POST_ROUTING,
964ddaa1 PM	217	.priority = NF_IP6_PRI_LAST,
964ddaa1 PM	218	},
12f7a505 PNA	219	{
12f7a505 PNA	220	.hook = ipv6_helper,
12f7a505 PNA	221	.pf = NFPROTO_IPV6,
	222	.hooknum = NF_INET_LOCAL_IN,
	223	.priority = NF_IP6_PRI_CONNTRACK_HELPER,
	224	},
964ddaa1 PM	225	{
964ddaa1 PM	226	.hook = ipv6_confirm,
57750a22	227	.pf = NFPROTO_IPV6,
6e23ae2a	228	.hooknum = NF_INET_LOCAL_IN,
964ddaa1 PM	229	.priority = NF_IP6_PRI_LAST-1,
964ddaa1 PM	230	},
9fb9cbb1 YK	231	};
9fb9cbb1 YK	232
121d1e09 FW	233	static int
	234	ipv6_getorigdst(struct sock sk, int optval, void __user user, int *len)
	235	{
	236	const struct inet_sock *inet = inet_sk(sk);
	237	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
	238	const struct nf_conntrack_tuple_hash *h;
	239	struct sockaddr_in6 sin6;
	240	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
	241	struct nf_conn *ct;
	242
efe4208f	243	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
121d1e09	244	tuple.src.u.tcp.port = inet->inet_sport;
efe4208f	245	tuple.dst.u3.in6 = sk->sk_v6_daddr;
121d1e09 FW	246	tuple.dst.u.tcp.port = inet->inet_dport;
	247	tuple.dst.protonum = sk->sk_protocol;
	248
	249	if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP)
	250	return -ENOPROTOOPT;
	251
	252	if (len < 0 \|\| (unsigned int) len < sizeof(sin6))
	253	return -EINVAL;
	254
308ac914	255	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
121d1e09 FW	256	if (!h) {
	257	pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
	258	&tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
	259	&tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
	260	return -ENOENT;
	261	}
	262
	263	ct = nf_ct_tuplehash_to_ctrack(h);
	264
	265	sin6.sin6_family = AF_INET6;
	266	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
	267	sin6.sin6_flowinfo = inet6->flow_label & IPV6_FLOWINFO_MASK;
	268	memcpy(&sin6.sin6_addr,
	269	&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
	270	sizeof(sin6.sin6_addr));
121d1e09 FW	271
121d1e09 FW	272	nf_ct_put(ct);
d00bd3d4 HFS	273	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr,
d00bd3d4 HFS	274	sk->sk_bound_dev_if);
121d1e09 FW	275	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
	276	}
	277
07a93626	278	#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
c1d10adb PNA	279
	280	#include <linux/netfilter/nfnetlink.h>
	281	#include <linux/netfilter/nfnetlink_conntrack.h>
	282
fdf70832	283	static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
c1d10adb PNA	284	const struct nf_conntrack_tuple *tuple)
c1d10adb PNA	285	{
930345ea JB	286	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) \|\|
930345ea JB	287	nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
e549a6b3	288	goto nla_put_failure;
c1d10adb PNA	289	return 0;
c1d10adb PNA	290
df6fb868	291	nla_put_failure:
c1d10adb PNA	292	return -1;
	293	}
	294
f73e924c PM	295	static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	296	[CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
	297	[CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
c1d10adb PNA	298	};
c1d10adb PNA	299
fdf70832	300	static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	301	struct nf_conntrack_tuple *t)
c1d10adb PNA	302	{
df6fb868	303	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	304	return -EINVAL;
c1d10adb PNA	305
67b61f6c JB	306	t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
67b61f6c JB	307	t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
c1d10adb PNA	308
	309	return 0;
	310	}
a400c30e HE	311
	312	static int ipv6_nlattr_tuple_size(void)
	313	{
	314	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
	315	}
c1d10adb PNA	316	#endif
c1d10adb PNA	317
0c66dc1e FW	318	static int ipv6_hooks_register(struct net *net)
	319	{
	320	struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);
	321	int err = 0;
	322
	323	mutex_lock(&register_ipv6_hooks);
	324	cnet->users++;
	325	if (cnet->users > 1)
	326	goto out_unlock;
	327
834184b1 FW	328	err = nf_defrag_ipv6_enable(net);
	329	if (err < 0) {
	330	cnet->users = 0;
	331	goto out_unlock;
	332	}
	333
0c66dc1e FW	334	err = nf_register_net_hooks(net, ipv6_conntrack_ops,
	335	ARRAY_SIZE(ipv6_conntrack_ops));
	336	if (err)
	337	cnet->users = 0;
	338	out_unlock:
	339	mutex_unlock(&register_ipv6_hooks);
	340	return err;
	341	}
	342
	343	static void ipv6_hooks_unregister(struct net *net)
	344	{
	345	struct conntrack6_net *cnet = net_generic(net, conntrack6_net_id);
	346
	347	mutex_lock(&register_ipv6_hooks);
	348	if (cnet->users && (--cnet->users == 0))
	349	nf_unregister_net_hooks(net, ipv6_conntrack_ops,
	350	ARRAY_SIZE(ipv6_conntrack_ops));
	351	mutex_unlock(&register_ipv6_hooks);
	352	}
	353
61075af5	354	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	355	.l3proto = PF_INET6,
	356	.name = "ipv6",
	357	.pkt_to_tuple = ipv6_pkt_to_tuple,
	358	.invert_tuple = ipv6_invert_tuple,
	359	.print_tuple = ipv6_print_tuple,
ffc30690	360	.get_l4proto = ipv6_get_l4proto,
07a93626	361	#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
fdf70832	362	.tuple_to_nlattr = ipv6_tuple_to_nlattr,
a400c30e	363	.nlattr_tuple_size = ipv6_nlattr_tuple_size,
fdf70832	364	.nlattr_to_tuple = ipv6_nlattr_to_tuple,
f73e924c	365	.nla_policy = ipv6_nla_policy,
c1d10adb	366	#endif
0c66dc1e FW	367	.net_ns_get = ipv6_hooks_register,
0c66dc1e FW	368	.net_ns_put = ipv6_hooks_unregister,
9fb9cbb1 YK	369	.me = THIS_MODULE,
	370	};
	371
32292a7f PM	372	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	373	MODULE_LICENSE("GPL");
	374	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	375
121d1e09 FW	376	static struct nf_sockopt_ops so_getorigdst6 = {
	377	.pf = NFPROTO_IPV6,
	378	.get_optmin = IP6T_SO_ORIGINAL_DST,
	379	.get_optmax = IP6T_SO_ORIGINAL_DST + 1,
	380	.get = ipv6_getorigdst,
	381	.owner = THIS_MODULE,
	382	};
	383
0e54d217 DC	384	static struct nf_conntrack_l4proto *builtin_l4proto6[] = {
	385	&nf_conntrack_l4proto_tcp6,
	386	&nf_conntrack_l4proto_udp6,
	387	&nf_conntrack_l4proto_icmpv6,
c51d3901 DC	388	#ifdef CONFIG_NF_CT_PROTO_DCCP
	389	&nf_conntrack_l4proto_dccp6,
	390	#endif
a85406af DC	391	#ifdef CONFIG_NF_CT_PROTO_SCTP
	392	&nf_conntrack_l4proto_sctp6,
	393	#endif
9b91c96c DC	394	#ifdef CONFIG_NF_CT_PROTO_UDPLITE
	395	&nf_conntrack_l4proto_udplite6,
	396	#endif
0e54d217 DC	397	};
0e54d217 DC	398
a7c439d3	399	static int ipv6_net_init(struct net *net)
9fb9cbb1 YK	400	{
	401	int ret = 0;
	402
0e54d217 DC	403	ret = nf_ct_l4proto_pernet_register(net, builtin_l4proto6,
	404	ARRAY_SIZE(builtin_l4proto6));
	405	if (ret < 0)
	406	return ret;
	407
6330750d	408	ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
9fb9cbb1	409	if (ret < 0) {
6330750d	410	pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
0e54d217 DC	411	nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
0e54d217 DC	412	ARRAY_SIZE(builtin_l4proto6));
9fb9cbb1	413	}
a7c439d3 G	414	return ret;
a7c439d3 G	415	}
9fb9cbb1	416
a7c439d3 G	417	static void ipv6_net_exit(struct net *net)
a7c439d3 G	418	{
6330750d	419	nf_ct_l3proto_pernet_unregister(net, &nf_conntrack_l3proto_ipv6);
0e54d217 DC	420	nf_ct_l4proto_pernet_unregister(net, builtin_l4proto6,
0e54d217 DC	421	ARRAY_SIZE(builtin_l4proto6));
a7c439d3 G	422	}
	423
	424	static struct pernet_operations ipv6_net_ops = {
	425	.init = ipv6_net_init,
	426	.exit = ipv6_net_exit,
0c66dc1e FW	427	.id = &conntrack6_net_id,
0c66dc1e FW	428	.size = sizeof(struct conntrack6_net),
a7c439d3 G	429	};
	430
	431	static int __init nf_conntrack_l3proto_ipv6_init(void)
	432	{
	433	int ret = 0;
	434
	435	need_conntrack();
a7c439d3	436
121d1e09 FW	437	ret = nf_register_sockopt(&so_getorigdst6);
	438	if (ret < 0) {
	439	pr_err("Unable to register netfilter socket option\n");
	440	return ret;
	441	}
	442
a7c439d3 G	443	ret = register_pernet_subsys(&ipv6_net_ops);
a7c439d3 G	444	if (ret < 0)
6330750d G	445	goto cleanup_sockopt;
6330750d G	446
0e54d217 DC	447	ret = nf_ct_l4proto_register(builtin_l4proto6,
	448	ARRAY_SIZE(builtin_l4proto6));
	449	if (ret < 0)
0c66dc1e	450	goto cleanup_pernet;
c296bb4d	451
6330750d G	452	ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv6);
	453	if (ret < 0) {
	454	pr_err("nf_conntrack_ipv6: can't register ipv6 proto.\n");
0e54d217	455	goto cleanup_l4proto;
9fb9cbb1	456	}
9fb9cbb1	457	return ret;
0e54d217 DC	458	cleanup_l4proto:
	459	nf_ct_l4proto_unregister(builtin_l4proto6,
	460	ARRAY_SIZE(builtin_l4proto6));
a7c439d3	461	cleanup_pernet:
6330750d G	462	unregister_pernet_subsys(&ipv6_net_ops);
6330750d G	463	cleanup_sockopt:
121d1e09	464	nf_unregister_sockopt(&so_getorigdst6);
9fb9cbb1 YK	465	return ret;
	466	}
	467
65b4b4e8	468	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	469	{
32292a7f	470	synchronize_net();
6330750d	471	nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
0e54d217 DC	472	nf_ct_l4proto_unregister(builtin_l4proto6,
0e54d217 DC	473	ARRAY_SIZE(builtin_l4proto6));
a7c439d3	474	unregister_pernet_subsys(&ipv6_net_ops);
121d1e09	475	nf_unregister_sockopt(&so_getorigdst6);
9fb9cbb1 YK	476	}
9fb9cbb1 YK	477
65b4b4e8 AM	478	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	479	module_exit(nf_conntrack_l3proto_ipv6_fini);