[mirror_ubuntu-jammy-kernel.git] / include / net / ipv6_frag.h

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _IPV6_FRAG_H
#define _IPV6_FRAG_H
#include <linux/kernel.h>
#include <net/addrconf.h>
#include <net/ipv6.h>
#include <net/inet_frag.h>

enum ip6_defrag_users {
	IP6_DEFRAG_LOCAL_DELIVER,
	IP6_DEFRAG_CONNTRACK_IN,
	__IP6_DEFRAG_CONNTRACK_IN	= IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
	IP6_DEFRAG_CONNTRACK_OUT,
	__IP6_DEFRAG_CONNTRACK_OUT	= IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
};

/*
 *	Equivalent of ipv4 struct ip
 */
struct frag_queue {
	struct inet_frag_queue	q;

	int			iif;
	__u16			nhoffset;
	u8			ecn;
};

#if IS_ENABLED(CONFIG_IPV6)
static inline void ip6frag_init(struct inet_frag_queue *q, const void *a)
{
	struct frag_queue *fq = container_of(q, struct frag_queue, q);
	const struct frag_v6_compare_key *key = a;

	q->key.v6 = *key;
	fq->ecn = 0;
}

static inline u32 ip6frag_key_hashfn(const void *data, u32 len, u32 seed)
{
	return jhash2(data,
		      sizeof(struct frag_v6_compare_key) / sizeof(u32), seed);
}

static inline u32 ip6frag_obj_hashfn(const void *data, u32 len, u32 seed)
{
	const struct inet_frag_queue *fq = data;

	return jhash2((const u32 *)&fq->key.v6,
		      sizeof(struct frag_v6_compare_key) / sizeof(u32), seed);
}

static inline int
ip6frag_obj_cmpfn(struct rhashtable_compare_arg *arg, const void *ptr)
{
	const struct frag_v6_compare_key *key = arg->key;
	const struct inet_frag_queue *fq = ptr;

	return !!memcmp(&fq->key, key, sizeof(*key));
}

static inline void
ip6frag_expire_frag_queue(struct net *net, struct frag_queue *fq)
{
	struct net_device *dev = NULL;
	struct sk_buff *head;

	rcu_read_lock();
	if (fq->q.fqdir->dead)
		goto out_rcu_unlock;
	spin_lock(&fq->q.lock);

	if (fq->q.flags & INET_FRAG_COMPLETE)
		goto out;

	inet_frag_kill(&fq->q);

	dev = dev_get_by_index_rcu(net, fq->iif);
	if (!dev)
		goto out;

	__IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
	__IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);

	/* Don't send error if the first segment did not arrive. */
	if (!(fq->q.flags & INET_FRAG_FIRST_IN))
		goto out;

	/* sk_buff::dev and sk_buff::rbnode are unionized. So we
	 * pull the head out of the tree in order to be able to
	 * deal with head->dev.
	 */
	head = inet_frag_pull_head(&fq->q);
	if (!head)
		goto out;

	head->dev = dev;
	spin_unlock(&fq->q.lock);

	icmpv6_send(head, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0);
	kfree_skb(head);
	goto out_rcu_unlock;

out:
	spin_unlock(&fq->q.lock);
out_rcu_unlock:
	rcu_read_unlock();
	inet_frag_put(&fq->q);
}

/* Check if the upper layer header is truncated in the first fragment. */
static inline bool
ipv6frag_thdr_truncated(struct sk_buff *skb, int start, u8 *nexthdrp)
{
	u8 nexthdr = *nexthdrp;
	__be16 frag_off;
	int offset;

	offset = ipv6_skip_exthdr(skb, start, &nexthdr, &frag_off);
	if (offset < 0 || (frag_off & htons(IP6_OFFSET)))
		return false;
	switch (nexthdr) {
	case NEXTHDR_TCP:
		offset += sizeof(struct tcphdr);
		break;
	case NEXTHDR_UDP:
		offset += sizeof(struct udphdr);
		break;
	case NEXTHDR_ICMP:
		offset += sizeof(struct icmp6hdr);
		break;
	default:
		offset += 1;
	}
	if (offset > skb->len)
		return true;
	return false;
}

#endif
#endif
Commit	Line	Data
70b095c8 FW	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	#ifndef _IPV6_FRAG_H
	3	#define _IPV6_FRAG_H
	4	#include <linux/kernel.h>
	5	#include <net/addrconf.h>
	6	#include <net/ipv6.h>
	7	#include <net/inet_frag.h>
	8
	9	enum ip6_defrag_users {
	10	IP6_DEFRAG_LOCAL_DELIVER,
	11	IP6_DEFRAG_CONNTRACK_IN,
	12	__IP6_DEFRAG_CONNTRACK_IN = IP6_DEFRAG_CONNTRACK_IN + USHRT_MAX,
	13	IP6_DEFRAG_CONNTRACK_OUT,
	14	__IP6_DEFRAG_CONNTRACK_OUT = IP6_DEFRAG_CONNTRACK_OUT + USHRT_MAX,
	15	IP6_DEFRAG_CONNTRACK_BRIDGE_IN,
	16	__IP6_DEFRAG_CONNTRACK_BRIDGE_IN = IP6_DEFRAG_CONNTRACK_BRIDGE_IN + USHRT_MAX,
	17	};
	18
	19	/*
	20	* Equivalent of ipv4 struct ip
	21	*/
	22	struct frag_queue {
	23	struct inet_frag_queue q;
	24
	25	int iif;
	26	__u16 nhoffset;
	27	u8 ecn;
	28	};
	29
	30	#if IS_ENABLED(CONFIG_IPV6)
	31	static inline void ip6frag_init(struct inet_frag_queue q, const void a)
	32	{
	33	struct frag_queue *fq = container_of(q, struct frag_queue, q);
	34	const struct frag_v6_compare_key *key = a;
	35
	36	q->key.v6 = *key;
	37	fq->ecn = 0;
	38	}
	39
	40	static inline u32 ip6frag_key_hashfn(const void *data, u32 len, u32 seed)
	41	{
	42	return jhash2(data,
	43	sizeof(struct frag_v6_compare_key) / sizeof(u32), seed);
	44	}
	45
	46	static inline u32 ip6frag_obj_hashfn(const void *data, u32 len, u32 seed)
	47	{
	48	const struct inet_frag_queue *fq = data;
	49
	50	return jhash2((const u32 *)&fq->key.v6,
	51	sizeof(struct frag_v6_compare_key) / sizeof(u32), seed);
	52	}
	53
	54	static inline int
	55	ip6frag_obj_cmpfn(struct rhashtable_compare_arg arg, const void ptr)
	56	{
	57	const struct frag_v6_compare_key *key = arg->key;
	58	const struct inet_frag_queue *fq = ptr;
	59
	60	return !!memcmp(&fq->key, key, sizeof(*key));
	61	}
	62
	63	static inline void
	64	ip6frag_expire_frag_queue(struct net net, struct frag_queue fq)
65	{
66	struct net_device *dev = NULL;
67	struct sk_buff *head;
68
69	rcu_read_lock();
d5dd8879 ED	70	if (fq->q.fqdir->dead)
d5dd8879 ED	71	goto out_rcu_unlock;
70b095c8 FW	72	spin_lock(&fq->q.lock);
	73
	74	if (fq->q.flags & INET_FRAG_COMPLETE)
	75	goto out;
	76
	77	inet_frag_kill(&fq->q);
	78
	79	dev = dev_get_by_index_rcu(net, fq->iif);
	80	if (!dev)
	81	goto out;
	82
	83	__IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_REASMFAILS);
	84	__IP6_INC_STATS(net, __in6_dev_get(dev), IPSTATS_MIB_REASMTIMEOUT);
	85
	86	/* Don't send error if the first segment did not arrive. */
d4289fcc PO	87	if (!(fq->q.flags & INET_FRAG_FIRST_IN))
	88	goto out;
	89
	90	/* sk_buff::dev and sk_buff::rbnode are unionized. So we
	91	* pull the head out of the tree in order to be able to
	92	* deal with head->dev.
	93	*/
	94	head = inet_frag_pull_head(&fq->q);
	95	if (!head)
70b095c8 FW	96	goto out;
	97
	98	head->dev = dev;
70b095c8 FW	99	spin_unlock(&fq->q.lock);
	100
	101	icmpv6_send(head, ICMPV6_TIME_EXCEED, ICMPV6_EXC_FRAGTIME, 0);
	102	kfree_skb(head);
	103	goto out_rcu_unlock;
	104
	105	out:
	106	spin_unlock(&fq->q.lock);
	107	out_rcu_unlock:
	108	rcu_read_unlock();
	109	inet_frag_put(&fq->q);
	110	}
2d8f6481 GK	111
	112	/* Check if the upper layer header is truncated in the first fragment. */
	113	static inline bool
	114	ipv6frag_thdr_truncated(struct sk_buff skb, int start, u8 nexthdrp)
	115	{
	116	u8 nexthdr = *nexthdrp;
	117	__be16 frag_off;
	118	int offset;
	119
	120	offset = ipv6_skip_exthdr(skb, start, &nexthdr, &frag_off);
	121	if (offset < 0 \|\| (frag_off & htons(IP6_OFFSET)))
	122	return false;
	123	switch (nexthdr) {
	124	case NEXTHDR_TCP:
	125	offset += sizeof(struct tcphdr);
	126	break;
	127	case NEXTHDR_UDP:
	128	offset += sizeof(struct udphdr);
	129	break;
	130	case NEXTHDR_ICMP:
	131	offset += sizeof(struct icmp6hdr);
	132	break;
	133	default:
	134	offset += 1;
	135	}
	136	if (offset > skb->len)
	137	return true;
	138	return false;
	139	}
	140
70b095c8 FW	141	#endif
70b095c8 FW	142	#endif