inet_frag.h | Explore in Territory

/* 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 { … };

/**
 * 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 { … };

struct frag_v4_compare_key { … };

struct frag_v6_compare_key { … };

/**
 * 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 inet_frags { … };

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);

static inline void fqdir_pre_exit(struct fqdir *fqdir)
{ … }
void fqdir_exit(struct fqdir *fqdir);

void inet_frag_kill(struct inet_frag_queue *q);
void inet_frag_destroy(struct inet_frag_queue *q);
struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key);

/* Free all skbs in the queue; return the sum of their truesizes. */
unsigned int inet_frag_rbtree_purge(struct rb_root *root,
				    enum skb_drop_reason reason);

static inline void inet_frag_put(struct inet_frag_queue *q)
{ … }

/* Memory Tracking Functions. */

static inline long frag_mem_limit(const struct fqdir *fqdir)
{ … }

static inline void sub_frag_mem_limit(struct fqdir *fqdir, long val)
{ … }

static inline void add_frag_mem_limit(struct fqdir *fqdir, long val)
{ … }

/* 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 …
#define IPFRAG_ECN_ECT_1 …
#define IPFRAG_ECN_ECT_0 …
#define IPFRAG_ECN_CE …

extern const u8 ip_frag_ecn_table[16];

/* Return values of inet_frag_queue_insert() */
#define IPFRAG_OK …
#define IPFRAG_DUP …
#define IPFRAG_OVERLAP …
int 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
linux/include/net/inet_frag.h
