/* SPDX-License-Identifier: GPL-2.0 */#ifndef __NET_FRAG_H__#define __NET_FRAG_H__ #include <linux/rhashtable-types.h>#include <linux/completion.h>#include <linux/in6.h>#include <linux/rbtree_types.h>#include <linux/refcount.h>#include <net/dropreason-core.h> /* Per netns frag queues directory */struct fqdir {	/* sysctls */	long			high_thresh;	long			low_thresh;	int			timeout;	int			max_dist;	struct inet_frags	*f;	struct net		*net;	bool			dead; 	struct rhashtable       rhashtable ____cacheline_aligned_in_smp; 	/* Keep atomic mem on separate cachelines in structs that include it */	atomic_long_t		mem ____cacheline_aligned_in_smp;	struct work_struct	destroy_work;	struct llist_node	free_list;}; /** * enum: fragment queue flags * * @INET_FRAG_FIRST_IN: first fragment has arrived * @INET_FRAG_LAST_IN: final fragment has arrived * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction * @INET_FRAG_HASH_DEAD: inet_frag_kill() has not removed fq from rhashtable * @INET_FRAG_DROP: if skbs must be dropped (instead of being consumed) */enum {	INET_FRAG_FIRST_IN	= BIT(0),	INET_FRAG_LAST_IN	= BIT(1),	INET_FRAG_COMPLETE	= BIT(2),	INET_FRAG_HASH_DEAD	= BIT(3),	INET_FRAG_DROP		= BIT(4),}; struct frag_v4_compare_key {	__be32		saddr;	__be32		daddr;	u32		user;	u32		vif;	__be16		id;	u16		protocol;}; struct frag_v6_compare_key {	struct in6_addr	saddr;	struct in6_addr	daddr;	u32		user;	__be32		id;	u32		iif;}; /** * struct inet_frag_queue - fragment queue * * @node: rhash node * @key: keys identifying this frag. * @timer: queue expiration timer * @lock: spinlock protecting this frag * @refcnt: reference count of the queue * @rb_fragments: received fragments rb-tree root * @fragments_tail: received fragments tail * @last_run_head: the head of the last "run". see ip_fragment.c * @stamp: timestamp of the last received fragment * @len: total length of the original datagram * @meat: length of received fragments so far * @tstamp_type: stamp has a mono delivery time (EDT) * @flags: fragment queue flags * @max_size: maximum received fragment size * @fqdir: pointer to struct fqdir * @rcu: rcu head for freeing deferall */struct inet_frag_queue {	struct rhash_head	node;	union {		struct frag_v4_compare_key v4;		struct frag_v6_compare_key v6;	} key;	struct timer_list	timer;	spinlock_t		lock;	refcount_t		refcnt;	struct rb_root		rb_fragments;	struct sk_buff		*fragments_tail;	struct sk_buff		*last_run_head;	ktime_t			stamp;	int			len;	int			meat;	u8			tstamp_type;	__u8			flags;	u16			max_size;	struct fqdir		*fqdir;	struct rcu_head		rcu;}; struct inet_frags {	unsigned int		qsize; 	void			(*constructor)(struct inet_frag_queue *q,					       const void *arg);	void			(*destructor)(struct inet_frag_queue *);	void			(*frag_expire)(struct timer_list *t);	struct kmem_cache	*frags_cachep;	const char		*frags_cache_name;	struct rhashtable_params rhash_params;	refcount_t		refcnt;	struct completion	completion;}; int inet_frags_init(struct inet_frags *);void inet_frags_fini(struct inet_frags *); int fqdir_init(struct fqdir **fqdirp, struct inet_frags *f, struct net *net); void fqdir_pre_exit(struct fqdir *fqdir);void fqdir_exit(struct fqdir *fqdir); void inet_frag_kill(struct inet_frag_queue *q, int *refs);void inet_frag_destroy(struct inet_frag_queue *q);struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key); void inet_frag_queue_flush(struct inet_frag_queue *q,			   enum skb_drop_reason reason); static inline void inet_frag_putn(struct inet_frag_queue *q, int refs){	if (refs && refcount_sub_and_test(refs, &q->refcnt))		inet_frag_destroy(q);} /* Memory Tracking Functions. */ static inline long frag_mem_limit(const struct fqdir *fqdir){	return atomic_long_read(&fqdir->mem);} static inline void sub_frag_mem_limit(struct fqdir *fqdir, long val){	atomic_long_sub(val, &fqdir->mem);} static inline void add_frag_mem_limit(struct fqdir *fqdir, long val){	atomic_long_add(val, &fqdir->mem);} /* RFC 3168 support : * We want to check ECN values of all fragments, do detect invalid combinations. * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value. */#define	IPFRAG_ECN_NOT_ECT	0x01 /* one frag had ECN_NOT_ECT */#define	IPFRAG_ECN_ECT_1	0x02 /* one frag had ECN_ECT_1 */#define	IPFRAG_ECN_ECT_0	0x04 /* one frag had ECN_ECT_0 */#define	IPFRAG_ECN_CE		0x08 /* one frag had ECN_CE */ extern const u8 ip_frag_ecn_table[16]; /* Return values of inet_frag_queue_insert() */#define IPFRAG_OK	0#define IPFRAG_DUP	1#define IPFRAG_OVERLAP	2int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb,			   int offset, int end);void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb,			      struct sk_buff *parent);void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head,			    void *reasm_data, bool try_coalesce);struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q); #endif