[deliverable/linux.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 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(const struct nf_hook_ops *ops,
				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_slow */
	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(const struct nf_hook_ops *ops,
				 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(const struct nf_hook_ops *ops,
				      struct sk_buff *skb,
				      const struct nf_hook_state *state)
{
	return nf_conntrack_in(dev_net(state->in), PF_INET6, ops->hooknum, skb);
}

static unsigned int ipv6_conntrack_local(const struct nf_hook_ops *ops,
					 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(dev_net(state->out), PF_INET6, ops->hooknum, skb);
}

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

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

	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_tcp6);
	if (ret < 0) {
		pr_err("nf_conntrack_tcp6: pernet registration failed\n");
		goto out;
	}
	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udp6);
	if (ret < 0) {
		pr_err("nf_conntrack_udp6: pernet registration failed\n");
		goto cleanup_tcp6;
	}
	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_icmpv6);
	if (ret < 0) {
		pr_err("nf_conntrack_icmp6: pernet registration failed\n");
		goto cleanup_udp6;
	}
	ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
		goto cleanup_icmpv6;
	}
	return 0;
 cleanup_icmpv6:
	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_icmpv6);
 cleanup_udp6:
	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
 cleanup_tcp6:
	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
 out:
	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, &nf_conntrack_l4proto_icmpv6);
	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
}

static struct pernet_operations ipv6_net_ops = {
	.init = ipv6_net_init,
	.exit = ipv6_net_exit,
};

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

	need_conntrack();
	nf_defrag_ipv6_enable();

	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_register_hooks(ipv6_conntrack_ops,
				ARRAY_SIZE(ipv6_conntrack_ops));
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: can't register pre-routing defrag "
		       "hook.\n");
		goto cleanup_pernet;
	}

	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_tcp6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: can't register tcp6 proto.\n");
		goto cleanup_hooks;
	}

	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udp6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: can't register udp6 proto.\n");
		goto cleanup_tcp6;
	}

	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_icmpv6);
	if (ret < 0) {
		pr_err("nf_conntrack_ipv6: can't register icmpv6 proto.\n");
		goto cleanup_udp6;
	}

	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_icmpv6;
	}
	return ret;

 cleanup_icmpv6:
	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
 cleanup_udp6:
	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
 cleanup_tcp6:
	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
 cleanup_hooks:
	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
 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(&nf_conntrack_l4proto_tcp6);
	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
	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
8ce8439a JE	37	static bool ipv6_pkt_to_tuple(const struct sk_buff *skb, unsigned int nhoff,
8ce8439a JE	38	struct nf_conntrack_tuple *tuple)
9fb9cbb1	39	{
32948588 JE	40	const u_int32_t *ap;
32948588 JE	41	u_int32_t _addrs[8];
9fb9cbb1 YK	42
	43	ap = skb_header_pointer(skb, nhoff + offsetof(struct ipv6hdr, saddr),
	44	sizeof(_addrs), _addrs);
	45	if (ap == NULL)
8ce8439a	46	return false;
9fb9cbb1 YK	47
	48	memcpy(tuple->src.u3.ip6, ap, sizeof(tuple->src.u3.ip6));
	49	memcpy(tuple->dst.u3.ip6, ap + 4, sizeof(tuple->dst.u3.ip6));
	50
8ce8439a	51	return true;
9fb9cbb1 YK	52	}
9fb9cbb1 YK	53
8ce8439a JE	54	static bool ipv6_invert_tuple(struct nf_conntrack_tuple *tuple,
8ce8439a JE	55	const struct nf_conntrack_tuple *orig)
9fb9cbb1 YK	56	{
	57	memcpy(tuple->src.u3.ip6, orig->dst.u3.ip6, sizeof(tuple->src.u3.ip6));
	58	memcpy(tuple->dst.u3.ip6, orig->src.u3.ip6, sizeof(tuple->dst.u3.ip6));
	59
8ce8439a	60	return true;
9fb9cbb1 YK	61	}
9fb9cbb1 YK	62
824f1fbe	63	static void ipv6_print_tuple(struct seq_file *s,
9fb9cbb1 YK	64	const struct nf_conntrack_tuple *tuple)
9fb9cbb1 YK	65	{
824f1fbe JP	66	seq_printf(s, "src=%pI6 dst=%pI6 ",
824f1fbe JP	67	tuple->src.u3.ip6, tuple->dst.u3.ip6);
9fb9cbb1 YK	68	}
9fb9cbb1 YK	69
ffc30690 YK	70	static int ipv6_get_l4proto(const struct sk_buff *skb, unsigned int nhoff,
ffc30690 YK	71	unsigned int dataoff, u_int8_t protonum)
9fb9cbb1	72	{
ffc30690	73	unsigned int extoff = nhoff + sizeof(struct ipv6hdr);
2b60af01	74	__be16 frag_off;
ffc30690	75	int protoff;
2b60af01	76	u8 nexthdr;
ffc30690 YK	77
ffc30690 YK	78	if (skb_copy_bits(skb, nhoff + offsetof(struct ipv6hdr, nexthdr),
2b60af01	79	&nexthdr, sizeof(nexthdr)) != 0) {
ffc30690 YK	80	pr_debug("ip6_conntrack_core: can't get nexthdr\n");
	81	return -NF_ACCEPT;
	82	}
2b60af01	83	protoff = ipv6_skip_exthdr(skb, extoff, &nexthdr, &frag_off);
9fb9cbb1	84	/*
d7a769ff FF	85	* (protoff == skb->len) means the packet has not data, just
d7a769ff FF	86	* IPv6 and possibly extensions headers, but it is tracked anyway
9fb9cbb1	87	*/
2b60af01	88	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
0d53778e	89	pr_debug("ip6_conntrack_core: can't find proto in pkt\n");
9fb9cbb1 YK	90	return -NF_ACCEPT;
	91	}
	92
	93	*dataoff = protoff;
2b60af01	94	*protonum = nexthdr;
9fb9cbb1 YK	95	return NF_ACCEPT;
	96	}
	97
795aa6ef	98	static unsigned int ipv6_helper(const struct nf_hook_ops *ops,
12f7a505	99	struct sk_buff *skb,
238e54c9	100	const struct nf_hook_state *state)
9fb9cbb1 YK	101	{
9fb9cbb1 YK	102	struct nf_conn *ct;
32948588 JE	103	const struct nf_conn_help *help;
32948588 JE	104	const struct nf_conntrack_helper *helper;
9fb9cbb1	105	enum ip_conntrack_info ctinfo;
4cdd3408 PM	106	__be16 frag_off;
	107	int protoff;
	108	u8 nexthdr;
9fb9cbb1 YK	109
9fb9cbb1 YK	110	/* This is where we call the helper: as the packet goes out. */
3db05fea	111	ct = nf_ct_get(skb, &ctinfo);
fb048833	112	if (!ct \|\| ctinfo == IP_CT_RELATED_REPLY)
12f7a505	113	return NF_ACCEPT;
dc808fe2 HW	114
dc808fe2 HW	115	help = nfct_help(ct);
3c158f7f	116	if (!help)
12f7a505	117	return NF_ACCEPT;
3c158f7f PM	118	/* rcu_read_lock()ed by nf_hook_slow */
	119	helper = rcu_dereference(help->helper);
	120	if (!helper)
12f7a505	121	return NF_ACCEPT;
dc808fe2	122
4cdd3408 PM	123	nexthdr = ipv6_hdr(skb)->nexthdr;
	124	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &nexthdr,
	125	&frag_off);
	126	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
0d53778e	127	pr_debug("proto header not found\n");
dc808fe2	128	return NF_ACCEPT;
9fb9cbb1 YK	129	}
9fb9cbb1 YK	130
b20ab9cc	131	return helper->help(skb, protoff, ct, ctinfo);
12f7a505 PNA	132	}
12f7a505 PNA	133
795aa6ef	134	static unsigned int ipv6_confirm(const struct nf_hook_ops *ops,
12f7a505	135	struct sk_buff *skb,
238e54c9	136	const struct nf_hook_state *state)
12f7a505	137	{
58a317f1 PM	138	struct nf_conn *ct;
	139	enum ip_conntrack_info ctinfo;
	140	unsigned char pnum = ipv6_hdr(skb)->nexthdr;
	141	int protoff;
	142	__be16 frag_off;
	143
	144	ct = nf_ct_get(skb, &ctinfo);
	145	if (!ct \|\| ctinfo == IP_CT_RELATED_REPLY)
	146	goto out;
	147
	148	protoff = ipv6_skip_exthdr(skb, sizeof(struct ipv6hdr), &pnum,
	149	&frag_off);
	150	if (protoff < 0 \|\| (frag_off & htons(~0x7)) != 0) {
	151	pr_debug("proto header not found\n");
	152	goto out;
	153	}
	154
	155	/* adjust seqs for loopback traffic only in outgoing direction */
	156	if (test_bit(IPS_SEQ_ADJUST_BIT, &ct->status) &&
	157	!nf_is_loopback_packet(skb)) {
41d73ec0	158	if (!nf_ct_seq_adjust(skb, ct, ctinfo, protoff)) {
58a317f1 PM	159	NF_CT_STAT_INC_ATOMIC(nf_ct_net(ct), drop);
	160	return NF_DROP;
	161	}
	162	}
	163	out:
9fb9cbb1	164	/* We've seen it coming out the other side: confirm it */
3db05fea	165	return nf_conntrack_confirm(skb);
9fb9cbb1 YK	166	}
9fb9cbb1 YK	167
795aa6ef	168	static unsigned int ipv6_conntrack_in(const struct nf_hook_ops *ops,
a702a65f	169	struct sk_buff *skb,
238e54c9	170	const struct nf_hook_state *state)
a702a65f	171	{
238e54c9	172	return nf_conntrack_in(dev_net(state->in), PF_INET6, ops->hooknum, skb);
9fb9cbb1 YK	173	}
9fb9cbb1 YK	174
795aa6ef	175	static unsigned int ipv6_conntrack_local(const struct nf_hook_ops *ops,
3db05fea	176	struct sk_buff *skb,
238e54c9	177	const struct nf_hook_state *state)
9fb9cbb1 YK	178	{
9fb9cbb1 YK	179	/* root is playing with raw sockets. */
3db05fea	180	if (skb->len < sizeof(struct ipv6hdr)) {
e87cc472	181	net_notice_ratelimited("ipv6_conntrack_local: packet too short\n");
9fb9cbb1 YK	182	return NF_ACCEPT;
9fb9cbb1 YK	183	}
238e54c9	184	return nf_conntrack_in(dev_net(state->out), PF_INET6, ops->hooknum, skb);
9fb9cbb1 YK	185	}
9fb9cbb1 YK	186
1999414a	187	static struct nf_hook_ops ipv6_conntrack_ops[] __read_mostly = {
964ddaa1 PM	188	{
	189	.hook = ipv6_conntrack_in,
	190	.owner = THIS_MODULE,
57750a22	191	.pf = NFPROTO_IPV6,
6e23ae2a	192	.hooknum = NF_INET_PRE_ROUTING,
964ddaa1 PM	193	.priority = NF_IP6_PRI_CONNTRACK,
	194	},
	195	{
	196	.hook = ipv6_conntrack_local,
	197	.owner = THIS_MODULE,
57750a22	198	.pf = NFPROTO_IPV6,
6e23ae2a	199	.hooknum = NF_INET_LOCAL_OUT,
964ddaa1 PM	200	.priority = NF_IP6_PRI_CONNTRACK,
964ddaa1 PM	201	},
12f7a505 PNA	202	{
	203	.hook = ipv6_helper,
	204	.owner = THIS_MODULE,
	205	.pf = NFPROTO_IPV6,
	206	.hooknum = NF_INET_POST_ROUTING,
	207	.priority = NF_IP6_PRI_CONNTRACK_HELPER,
	208	},
964ddaa1 PM	209	{
	210	.hook = ipv6_confirm,
	211	.owner = THIS_MODULE,
57750a22	212	.pf = NFPROTO_IPV6,
6e23ae2a	213	.hooknum = NF_INET_POST_ROUTING,
964ddaa1 PM	214	.priority = NF_IP6_PRI_LAST,
964ddaa1 PM	215	},
12f7a505 PNA	216	{
	217	.hook = ipv6_helper,
	218	.owner = THIS_MODULE,
	219	.pf = NFPROTO_IPV6,
	220	.hooknum = NF_INET_LOCAL_IN,
	221	.priority = NF_IP6_PRI_CONNTRACK_HELPER,
	222	},
964ddaa1 PM	223	{
	224	.hook = ipv6_confirm,
	225	.owner = THIS_MODULE,
57750a22	226	.pf = NFPROTO_IPV6,
6e23ae2a	227	.hooknum = NF_INET_LOCAL_IN,
964ddaa1 PM	228	.priority = NF_IP6_PRI_LAST-1,
964ddaa1 PM	229	},
9fb9cbb1 YK	230	};
9fb9cbb1 YK	231
121d1e09 FW	232	static int
	233	ipv6_getorigdst(struct sock sk, int optval, void __user user, int *len)
	234	{
	235	const struct inet_sock *inet = inet_sk(sk);
	236	const struct ipv6_pinfo *inet6 = inet6_sk(sk);
	237	const struct nf_conntrack_tuple_hash *h;
	238	struct sockaddr_in6 sin6;
	239	struct nf_conntrack_tuple tuple = { .src.l3num = NFPROTO_IPV6 };
	240	struct nf_conn *ct;
	241
efe4208f	242	tuple.src.u3.in6 = sk->sk_v6_rcv_saddr;
121d1e09	243	tuple.src.u.tcp.port = inet->inet_sport;
efe4208f	244	tuple.dst.u3.in6 = sk->sk_v6_daddr;
121d1e09 FW	245	tuple.dst.u.tcp.port = inet->inet_dport;
	246	tuple.dst.protonum = sk->sk_protocol;
	247
	248	if (sk->sk_protocol != IPPROTO_TCP && sk->sk_protocol != IPPROTO_SCTP)
	249	return -ENOPROTOOPT;
	250
	251	if (len < 0 \|\| (unsigned int) len < sizeof(sin6))
	252	return -EINVAL;
	253
308ac914	254	h = nf_conntrack_find_get(sock_net(sk), &nf_ct_zone_dflt, &tuple);
121d1e09 FW	255	if (!h) {
	256	pr_debug("IP6T_SO_ORIGINAL_DST: Can't find %pI6c/%u-%pI6c/%u.\n",
	257	&tuple.src.u3.ip6, ntohs(tuple.src.u.tcp.port),
	258	&tuple.dst.u3.ip6, ntohs(tuple.dst.u.tcp.port));
	259	return -ENOENT;
	260	}
	261
	262	ct = nf_ct_tuplehash_to_ctrack(h);
	263
	264	sin6.sin6_family = AF_INET6;
	265	sin6.sin6_port = ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u.tcp.port;
	266	sin6.sin6_flowinfo = inet6->flow_label & IPV6_FLOWINFO_MASK;
	267	memcpy(&sin6.sin6_addr,
	268	&ct->tuplehash[IP_CT_DIR_ORIGINAL].tuple.dst.u3.in6,
	269	sizeof(sin6.sin6_addr));
121d1e09 FW	270
121d1e09 FW	271	nf_ct_put(ct);
d00bd3d4 HFS	272	sin6.sin6_scope_id = ipv6_iface_scope_id(&sin6.sin6_addr,
d00bd3d4 HFS	273	sk->sk_bound_dev_if);
121d1e09 FW	274	return copy_to_user(user, &sin6, sizeof(sin6)) ? -EFAULT : 0;
	275	}
	276
07a93626	277	#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
c1d10adb PNA	278
	279	#include <linux/netfilter/nfnetlink.h>
	280	#include <linux/netfilter/nfnetlink_conntrack.h>
	281
fdf70832	282	static int ipv6_tuple_to_nlattr(struct sk_buff *skb,
c1d10adb PNA	283	const struct nf_conntrack_tuple *tuple)
c1d10adb PNA	284	{
930345ea JB	285	if (nla_put_in6_addr(skb, CTA_IP_V6_SRC, &tuple->src.u3.in6) \|\|
930345ea JB	286	nla_put_in6_addr(skb, CTA_IP_V6_DST, &tuple->dst.u3.in6))
e549a6b3	287	goto nla_put_failure;
c1d10adb PNA	288	return 0;
c1d10adb PNA	289
df6fb868	290	nla_put_failure:
c1d10adb PNA	291	return -1;
	292	}
	293
f73e924c PM	294	static const struct nla_policy ipv6_nla_policy[CTA_IP_MAX+1] = {
	295	[CTA_IP_V6_SRC] = { .len = sizeof(u_int32_t)*4 },
	296	[CTA_IP_V6_DST] = { .len = sizeof(u_int32_t)*4 },
c1d10adb PNA	297	};
c1d10adb PNA	298
fdf70832	299	static int ipv6_nlattr_to_tuple(struct nlattr *tb[],
c1d10adb PNA	300	struct nf_conntrack_tuple *t)
c1d10adb PNA	301	{
df6fb868	302	if (!tb[CTA_IP_V6_SRC] \|\| !tb[CTA_IP_V6_DST])
c1d10adb PNA	303	return -EINVAL;
c1d10adb PNA	304
67b61f6c JB	305	t->src.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_SRC]);
67b61f6c JB	306	t->dst.u3.in6 = nla_get_in6_addr(tb[CTA_IP_V6_DST]);
c1d10adb PNA	307
	308	return 0;
	309	}
a400c30e HE	310
	311	static int ipv6_nlattr_tuple_size(void)
	312	{
	313	return nla_policy_len(ipv6_nla_policy, CTA_IP_MAX + 1);
	314	}
c1d10adb PNA	315	#endif
c1d10adb PNA	316
61075af5	317	struct nf_conntrack_l3proto nf_conntrack_l3proto_ipv6 __read_mostly = {
9fb9cbb1 YK	318	.l3proto = PF_INET6,
	319	.name = "ipv6",
	320	.pkt_to_tuple = ipv6_pkt_to_tuple,
	321	.invert_tuple = ipv6_invert_tuple,
	322	.print_tuple = ipv6_print_tuple,
ffc30690	323	.get_l4proto = ipv6_get_l4proto,
07a93626	324	#if IS_ENABLED(CONFIG_NF_CT_NETLINK)
fdf70832	325	.tuple_to_nlattr = ipv6_tuple_to_nlattr,
a400c30e	326	.nlattr_tuple_size = ipv6_nlattr_tuple_size,
fdf70832	327	.nlattr_to_tuple = ipv6_nlattr_to_tuple,
f73e924c	328	.nla_policy = ipv6_nla_policy,
c1d10adb	329	#endif
9fb9cbb1 YK	330	.me = THIS_MODULE,
	331	};
	332
32292a7f PM	333	MODULE_ALIAS("nf_conntrack-" __stringify(AF_INET6));
	334	MODULE_LICENSE("GPL");
	335	MODULE_AUTHOR("Yasuyuki KOZAKAI @USAGI <yasuyuki.kozakai@toshiba.co.jp>");
	336
121d1e09 FW	337	static struct nf_sockopt_ops so_getorigdst6 = {
	338	.pf = NFPROTO_IPV6,
	339	.get_optmin = IP6T_SO_ORIGINAL_DST,
	340	.get_optmax = IP6T_SO_ORIGINAL_DST + 1,
	341	.get = ipv6_getorigdst,
	342	.owner = THIS_MODULE,
	343	};
	344
a7c439d3	345	static int ipv6_net_init(struct net *net)
9fb9cbb1 YK	346	{
	347	int ret = 0;
	348
c296bb4d	349	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_tcp6);
9fb9cbb1	350	if (ret < 0) {
c296bb4d	351	pr_err("nf_conntrack_tcp6: pernet registration failed\n");
a7c439d3	352	goto out;
9fb9cbb1	353	}
c296bb4d	354	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_udp6);
9fb9cbb1	355	if (ret < 0) {
c296bb4d	356	pr_err("nf_conntrack_udp6: pernet registration failed\n");
a7c439d3	357	goto cleanup_tcp6;
9fb9cbb1	358	}
c296bb4d	359	ret = nf_ct_l4proto_pernet_register(net, &nf_conntrack_l4proto_icmpv6);
9fb9cbb1	360	if (ret < 0) {
c296bb4d	361	pr_err("nf_conntrack_icmp6: pernet registration failed\n");
a7c439d3	362	goto cleanup_udp6;
9fb9cbb1	363	}
6330750d	364	ret = nf_ct_l3proto_pernet_register(net, &nf_conntrack_l3proto_ipv6);
9fb9cbb1	365	if (ret < 0) {
6330750d	366	pr_err("nf_conntrack_ipv6: pernet registration failed.\n");
9fb9cbb1 YK	367	goto cleanup_icmpv6;
9fb9cbb1 YK	368	}
a7c439d3 G	369	return 0;
a7c439d3 G	370	cleanup_icmpv6:
c296bb4d	371	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_icmpv6);
a7c439d3	372	cleanup_udp6:
c296bb4d	373	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
a7c439d3	374	cleanup_tcp6:
c296bb4d	375	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
a7c439d3 G	376	out:
	377	return ret;
	378	}
9fb9cbb1	379
a7c439d3 G	380	static void ipv6_net_exit(struct net *net)
a7c439d3 G	381	{
6330750d	382	nf_ct_l3proto_pernet_unregister(net, &nf_conntrack_l3proto_ipv6);
c296bb4d G	383	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_icmpv6);
	384	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_udp6);
	385	nf_ct_l4proto_pernet_unregister(net, &nf_conntrack_l4proto_tcp6);
a7c439d3 G	386	}
	387
	388	static struct pernet_operations ipv6_net_ops = {
	389	.init = ipv6_net_init,
	390	.exit = ipv6_net_exit,
	391	};
	392
	393	static int __init nf_conntrack_l3proto_ipv6_init(void)
	394	{
	395	int ret = 0;
	396
	397	need_conntrack();
	398	nf_defrag_ipv6_enable();
	399
121d1e09 FW	400	ret = nf_register_sockopt(&so_getorigdst6);
	401	if (ret < 0) {
	402	pr_err("Unable to register netfilter socket option\n");
	403	return ret;
	404	}
	405
a7c439d3 G	406	ret = register_pernet_subsys(&ipv6_net_ops);
a7c439d3 G	407	if (ret < 0)
6330750d G	408	goto cleanup_sockopt;
6330750d G	409
964ddaa1 PM	410	ret = nf_register_hooks(ipv6_conntrack_ops,
964ddaa1 PM	411	ARRAY_SIZE(ipv6_conntrack_ops));
9fb9cbb1	412	if (ret < 0) {
654d0fbd	413	pr_err("nf_conntrack_ipv6: can't register pre-routing defrag "
9fb9cbb1	414	"hook.\n");
6330750d G	415	goto cleanup_pernet;
	416	}
	417
c296bb4d G	418	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_tcp6);
	419	if (ret < 0) {
	420	pr_err("nf_conntrack_ipv6: can't register tcp6 proto.\n");
	421	goto cleanup_hooks;
	422	}
	423
	424	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_udp6);
	425	if (ret < 0) {
	426	pr_err("nf_conntrack_ipv6: can't register udp6 proto.\n");
	427	goto cleanup_tcp6;
	428	}
	429
	430	ret = nf_ct_l4proto_register(&nf_conntrack_l4proto_icmpv6);
	431	if (ret < 0) {
	432	pr_err("nf_conntrack_ipv6: can't register icmpv6 proto.\n");
	433	goto cleanup_udp6;
	434	}
	435
6330750d G	436	ret = nf_ct_l3proto_register(&nf_conntrack_l3proto_ipv6);
	437	if (ret < 0) {
	438	pr_err("nf_conntrack_ipv6: can't register ipv6 proto.\n");
c296bb4d	439	goto cleanup_icmpv6;
9fb9cbb1	440	}
9fb9cbb1 YK	441	return ret;
9fb9cbb1 YK	442
c296bb4d G	443	cleanup_icmpv6:
	444	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
	445	cleanup_udp6:
	446	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	447	cleanup_tcp6:
	448	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
6330750d G	449	cleanup_hooks:
6330750d G	450	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
a7c439d3	451	cleanup_pernet:
6330750d G	452	unregister_pernet_subsys(&ipv6_net_ops);
6330750d G	453	cleanup_sockopt:
121d1e09	454	nf_unregister_sockopt(&so_getorigdst6);
9fb9cbb1 YK	455	return ret;
	456	}
	457
65b4b4e8	458	static void __exit nf_conntrack_l3proto_ipv6_fini(void)
9fb9cbb1	459	{
32292a7f	460	synchronize_net();
6330750d	461	nf_ct_l3proto_unregister(&nf_conntrack_l3proto_ipv6);
c296bb4d G	462	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_tcp6);
	463	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_udp6);
	464	nf_ct_l4proto_unregister(&nf_conntrack_l4proto_icmpv6);
32292a7f	465	nf_unregister_hooks(ipv6_conntrack_ops, ARRAY_SIZE(ipv6_conntrack_ops));
a7c439d3	466	unregister_pernet_subsys(&ipv6_net_ops);
121d1e09	467	nf_unregister_sockopt(&so_getorigdst6);
9fb9cbb1 YK	468	}
9fb9cbb1 YK	469
65b4b4e8 AM	470	module_init(nf_conntrack_l3proto_ipv6_init);
65b4b4e8 AM	471	module_exit(nf_conntrack_l3proto_ipv6_fini);