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
  9enum 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 */
 22struct 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)
 31static 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
 40static 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
 46static 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
 54static inline int
 55ip6frag_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
 63static inline void
 64ip6frag_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();
 70	if (fq->q.fqdir->dead)
 71		goto out_rcu_unlock;
 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. */
 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)
 96		goto out;
 97
 98	head->dev = dev;
 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
105out:
106	spin_unlock(&fq->q.lock);
107out_rcu_unlock:
108	rcu_read_unlock();
109	inet_frag_put(&fq->q);
110}
111#endif
112#endif