[mirror_ubuntu-bionic-kernel.git] / net / ipv6 / netfilter / nf_defrag_ipv6_hooks.c

/* (C) 1999-2001 Paul `Rusty' Russell
 * (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
 *
 * 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.
 */

#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 <linux/sysctl.h>
#include <net/ipv6.h>
#include <net/inet_frag.h>

#include <linux/netfilter_ipv6.h>
#include <linux/netfilter_bridge.h>
#if IS_ENABLED(CONFIG_NF_CONNTRACK)
#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/ipv6/nf_conntrack_ipv6.h>
#endif
#include <net/netfilter/nf_conntrack_zones.h>
#include <net/netfilter/ipv6/nf_defrag_ipv6.h>

static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
						struct sk_buff *skb)
{
	u16 zone = NF_CT_DEFAULT_ZONE;

#if IS_ENABLED(CONFIG_NF_CONNTRACK)
	if (skb->nfct)
		zone = nf_ct_zone((struct nf_conn *)skb->nfct);
#endif

#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
	if (skb->nf_bridge &&
	    skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
		return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone;
#endif
	if (hooknum == NF_INET_PRE_ROUTING)
		return IP6_DEFRAG_CONNTRACK_IN + zone;
	else
		return IP6_DEFRAG_CONNTRACK_OUT + zone;

}

static unsigned int ipv6_defrag(const struct nf_hook_ops *ops,
				struct sk_buff *skb,
				const struct nf_hook_state *state)
{
	struct sk_buff *reasm;

#if IS_ENABLED(CONFIG_NF_CONNTRACK)
	/* Previously seen (loopback)?	*/
	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
		return NF_ACCEPT;
#endif

	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(ops->hooknum, skb));
	/* queued */
	if (reasm == NULL)
		return NF_STOLEN;

	/* error occurred or not fragmented */
	if (reasm == skb)
		return NF_ACCEPT;

	nf_ct_frag6_consume_orig(reasm);

	NF_HOOK_THRESH(NFPROTO_IPV6, ops->hooknum, state->sk, reasm,
		       state->in, state->out,
		       state->okfn, NF_IP6_PRI_CONNTRACK_DEFRAG + 1);

	return NF_STOLEN;
}

static struct nf_hook_ops ipv6_defrag_ops[] = {
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_PRE_ROUTING,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
	{
		.hook		= ipv6_defrag,
		.owner		= THIS_MODULE,
		.pf		= NFPROTO_IPV6,
		.hooknum	= NF_INET_LOCAL_OUT,
		.priority	= NF_IP6_PRI_CONNTRACK_DEFRAG,
	},
};

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

	ret = nf_ct_frag6_init();
	if (ret < 0) {
		pr_err("nf_defrag_ipv6: can't initialize frag6.\n");
		return ret;
	}
	ret = nf_register_hooks(ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops));
	if (ret < 0) {
		pr_err("nf_defrag_ipv6: can't register hooks\n");
		goto cleanup_frag6;
	}
	return ret;

cleanup_frag6:
	nf_ct_frag6_cleanup();
	return ret;

}

static void __exit nf_defrag_fini(void)
{
	nf_unregister_hooks(ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops));
	nf_ct_frag6_cleanup();
}

void nf_defrag_ipv6_enable(void)
{
}
EXPORT_SYMBOL_GPL(nf_defrag_ipv6_enable);

module_init(nf_defrag_init);
module_exit(nf_defrag_fini);

MODULE_LICENSE("GPL");
Commit	Line	Data
e97c3e27 BS	1	/* (C) 1999-2001 Paul `Rusty' Russell
	2	* (C) 2002-2004 Netfilter Core Team <coreteam@netfilter.org>
	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
	9	#include <linux/types.h>
	10	#include <linux/ipv6.h>
	11	#include <linux/in6.h>
	12	#include <linux/netfilter.h>
	13	#include <linux/module.h>
	14	#include <linux/skbuff.h>
	15	#include <linux/icmp.h>
	16	#include <linux/sysctl.h>
	17	#include <net/ipv6.h>
	18	#include <net/inet_frag.h>
	19
	20	#include <linux/netfilter_ipv6.h>
	21	#include <linux/netfilter_bridge.h>
07a93626	22	#if IS_ENABLED(CONFIG_NF_CONNTRACK)
e97c3e27 BS	23	#include <net/netfilter/nf_conntrack.h>
	24	#include <net/netfilter/nf_conntrack_helper.h>
	25	#include <net/netfilter/nf_conntrack_l4proto.h>
	26	#include <net/netfilter/nf_conntrack_l3proto.h>
	27	#include <net/netfilter/nf_conntrack_core.h>
e97c3e27	28	#include <net/netfilter/ipv6/nf_conntrack_ipv6.h>
2fc72c7b KK	29	#endif
2fc72c7b KK	30	#include <net/netfilter/nf_conntrack_zones.h>
e97c3e27 BS	31	#include <net/netfilter/ipv6/nf_defrag_ipv6.h>
	32
	33	static enum ip6_defrag_users nf_ct6_defrag_user(unsigned int hooknum,
	34	struct sk_buff *skb)
	35	{
	36	u16 zone = NF_CT_DEFAULT_ZONE;
	37
07a93626	38	#if IS_ENABLED(CONFIG_NF_CONNTRACK)
e97c3e27 BS	39	if (skb->nfct)
e97c3e27 BS	40	zone = nf_ct_zone((struct nf_conn *)skb->nfct);
2fc72c7b	41	#endif
e97c3e27	42
1109a90c	43	#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
e97c3e27 BS	44	if (skb->nf_bridge &&
	45	skb->nf_bridge->mask & BRNF_NF_BRIDGE_PREROUTING)
	46	return IP6_DEFRAG_CONNTRACK_BRIDGE_IN + zone;
	47	#endif
	48	if (hooknum == NF_INET_PRE_ROUTING)
	49	return IP6_DEFRAG_CONNTRACK_IN + zone;
	50	else
	51	return IP6_DEFRAG_CONNTRACK_OUT + zone;
	52
	53	}
	54
795aa6ef	55	static unsigned int ipv6_defrag(const struct nf_hook_ops *ops,
e97c3e27	56	struct sk_buff *skb,
238e54c9	57	const struct nf_hook_state *state)
e97c3e27 BS	58	{
	59	struct sk_buff *reasm;
	60
07a93626	61	#if IS_ENABLED(CONFIG_NF_CONNTRACK)
e97c3e27 BS	62	/* Previously seen (loopback)? */
	63	if (skb->nfct && !nf_ct_is_template((struct nf_conn *)skb->nfct))
	64	return NF_ACCEPT;
2fc72c7b	65	#endif
e97c3e27	66
795aa6ef	67	reasm = nf_ct_frag6_gather(skb, nf_ct6_defrag_user(ops->hooknum, skb));
e97c3e27 BS	68	/* queued */
	69	if (reasm == NULL)
	70	return NF_STOLEN;
	71
25985edc	72	/* error occurred or not fragmented */
e97c3e27 BS	73	if (reasm == skb)
	74	return NF_ACCEPT;
	75
6aafeef0 JP	76	nf_ct_frag6_consume_orig(reasm);
6aafeef0 JP	77
7026b1dd	78	NF_HOOK_THRESH(NFPROTO_IPV6, ops->hooknum, state->sk, reasm,
238e54c9 DM	79	state->in, state->out,
238e54c9 DM	80	state->okfn, NF_IP6_PRI_CONNTRACK_DEFRAG + 1);
e97c3e27 BS	81
	82	return NF_STOLEN;
	83	}
	84
	85	static struct nf_hook_ops ipv6_defrag_ops[] = {
	86	{
	87	.hook = ipv6_defrag,
	88	.owner = THIS_MODULE,
	89	.pf = NFPROTO_IPV6,
	90	.hooknum = NF_INET_PRE_ROUTING,
	91	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	92	},
	93	{
	94	.hook = ipv6_defrag,
	95	.owner = THIS_MODULE,
	96	.pf = NFPROTO_IPV6,
	97	.hooknum = NF_INET_LOCAL_OUT,
	98	.priority = NF_IP6_PRI_CONNTRACK_DEFRAG,
	99	},
	100	};
	101
	102	static int __init nf_defrag_init(void)
	103	{
	104	int ret = 0;
	105
	106	ret = nf_ct_frag6_init();
	107	if (ret < 0) {
	108	pr_err("nf_defrag_ipv6: can't initialize frag6.\n");
	109	return ret;
	110	}
	111	ret = nf_register_hooks(ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops));
	112	if (ret < 0) {
	113	pr_err("nf_defrag_ipv6: can't register hooks\n");
	114	goto cleanup_frag6;
	115	}
	116	return ret;
	117
	118	cleanup_frag6:
	119	nf_ct_frag6_cleanup();
	120	return ret;
	121
	122	}
	123
	124	static void __exit nf_defrag_fini(void)
	125	{
	126	nf_unregister_hooks(ipv6_defrag_ops, ARRAY_SIZE(ipv6_defrag_ops));
	127	nf_ct_frag6_cleanup();
	128	}
	129
	130	void nf_defrag_ipv6_enable(void)
	131	{
	132	}
	133	EXPORT_SYMBOL_GPL(nf_defrag_ipv6_enable);
	134
	135	module_init(nf_defrag_init);
	136	module_exit(nf_defrag_fini);
	137
	138	MODULE_LICENSE("GPL");