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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NET_FRAG_H__
3#define __NET_FRAG_H__
4
5#include <linux/rhashtable.h>
6
7struct netns_frags {
8 /* sysctls */
9 long high_thresh;
10 long low_thresh;
11 int timeout;
12 int max_dist;
13 struct inet_frags *f;
14
15 struct rhashtable rhashtable ____cacheline_aligned_in_smp;
16
17 /* Keep atomic mem on separate cachelines in structs that include it */
18 atomic_long_t mem ____cacheline_aligned_in_smp;
19};
20
21/**
22 * fragment queue flags
23 *
24 * @INET_FRAG_FIRST_IN: first fragment has arrived
25 * @INET_FRAG_LAST_IN: final fragment has arrived
26 * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction
27 */
28enum {
29 INET_FRAG_FIRST_IN = BIT(0),
30 INET_FRAG_LAST_IN = BIT(1),
31 INET_FRAG_COMPLETE = BIT(2),
32};
33
34struct frag_v4_compare_key {
35 __be32 saddr;
36 __be32 daddr;
37 u32 user;
38 u32 vif;
39 __be16 id;
40 u16 protocol;
41};
42
43struct frag_v6_compare_key {
44 struct in6_addr saddr;
45 struct in6_addr daddr;
46 u32 user;
47 __be32 id;
48 u32 iif;
49};
50
51/**
52 * struct inet_frag_queue - fragment queue
53 *
54 * @node: rhash node
55 * @key: keys identifying this frag.
56 * @timer: queue expiration timer
57 * @lock: spinlock protecting this frag
58 * @refcnt: reference count of the queue
59 * @fragments: received fragments head
60 * @fragments_tail: received fragments tail
61 * @stamp: timestamp of the last received fragment
62 * @len: total length of the original datagram
63 * @meat: length of received fragments so far
64 * @flags: fragment queue flags
65 * @max_size: maximum received fragment size
66 * @net: namespace that this frag belongs to
67 * @rcu: rcu head for freeing deferall
68 */
69struct inet_frag_queue {
70 struct rhash_head node;
71 union {
72 struct frag_v4_compare_key v4;
73 struct frag_v6_compare_key v6;
74 } key;
75 struct timer_list timer;
76 spinlock_t lock;
77 refcount_t refcnt;
78 struct sk_buff *fragments;
79 struct sk_buff *fragments_tail;
80 ktime_t stamp;
81 int len;
82 int meat;
83 __u8 flags;
84 u16 max_size;
85 struct netns_frags *net;
86 struct rcu_head rcu;
87};
88
89struct inet_frags {
90 unsigned int qsize;
91
92 void (*constructor)(struct inet_frag_queue *q,
93 const void *arg);
94 void (*destructor)(struct inet_frag_queue *);
95 void (*frag_expire)(struct timer_list *t);
96 struct kmem_cache *frags_cachep;
97 const char *frags_cache_name;
98 struct rhashtable_params rhash_params;
99};
100
101int inet_frags_init(struct inet_frags *);
102void inet_frags_fini(struct inet_frags *);
103
104static inline int inet_frags_init_net(struct netns_frags *nf)
105{
106 atomic_long_set(&nf->mem, 0);
107 return rhashtable_init(&nf->rhashtable, &nf->f->rhash_params);
108}
109void inet_frags_exit_net(struct netns_frags *nf);
110
111void inet_frag_kill(struct inet_frag_queue *q);
112void inet_frag_destroy(struct inet_frag_queue *q);
113struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, void *key);
114
115static inline void inet_frag_put(struct inet_frag_queue *q)
116{
117 if (refcount_dec_and_test(&q->refcnt))
118 inet_frag_destroy(q);
119}
120
121/* Memory Tracking Functions. */
122
123static inline long frag_mem_limit(const struct netns_frags *nf)
124{
125 return atomic_long_read(&nf->mem);
126}
127
128static inline void sub_frag_mem_limit(struct netns_frags *nf, long val)
129{
130 atomic_long_sub(val, &nf->mem);
131}
132
133static inline void add_frag_mem_limit(struct netns_frags *nf, long val)
134{
135 atomic_long_add(val, &nf->mem);
136}
137
138/* RFC 3168 support :
139 * We want to check ECN values of all fragments, do detect invalid combinations.
140 * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value.
141 */
142#define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */
143#define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */
144#define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */
145#define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */
146
147extern const u8 ip_frag_ecn_table[16];
148
149#endif
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __NET_FRAG_H__
3#define __NET_FRAG_H__
4
5#include <linux/rhashtable-types.h>
6#include <linux/completion.h>
7
8/* Per netns frag queues directory */
9struct fqdir {
10 /* sysctls */
11 long high_thresh;
12 long low_thresh;
13 int timeout;
14 int max_dist;
15 struct inet_frags *f;
16 struct net *net;
17 bool dead;
18
19 struct rhashtable rhashtable ____cacheline_aligned_in_smp;
20
21 /* Keep atomic mem on separate cachelines in structs that include it */
22 atomic_long_t mem ____cacheline_aligned_in_smp;
23 struct work_struct destroy_work;
24 struct llist_node free_list;
25};
26
27/**
28 * fragment queue flags
29 *
30 * @INET_FRAG_FIRST_IN: first fragment has arrived
31 * @INET_FRAG_LAST_IN: final fragment has arrived
32 * @INET_FRAG_COMPLETE: frag queue has been processed and is due for destruction
33 * @INET_FRAG_HASH_DEAD: inet_frag_kill() has not removed fq from rhashtable
34 */
35enum {
36 INET_FRAG_FIRST_IN = BIT(0),
37 INET_FRAG_LAST_IN = BIT(1),
38 INET_FRAG_COMPLETE = BIT(2),
39 INET_FRAG_HASH_DEAD = BIT(3),
40};
41
42struct frag_v4_compare_key {
43 __be32 saddr;
44 __be32 daddr;
45 u32 user;
46 u32 vif;
47 __be16 id;
48 u16 protocol;
49};
50
51struct frag_v6_compare_key {
52 struct in6_addr saddr;
53 struct in6_addr daddr;
54 u32 user;
55 __be32 id;
56 u32 iif;
57};
58
59/**
60 * struct inet_frag_queue - fragment queue
61 *
62 * @node: rhash node
63 * @key: keys identifying this frag.
64 * @timer: queue expiration timer
65 * @lock: spinlock protecting this frag
66 * @refcnt: reference count of the queue
67 * @rb_fragments: received fragments rb-tree root
68 * @fragments_tail: received fragments tail
69 * @last_run_head: the head of the last "run". see ip_fragment.c
70 * @stamp: timestamp of the last received fragment
71 * @len: total length of the original datagram
72 * @meat: length of received fragments so far
73 * @flags: fragment queue flags
74 * @max_size: maximum received fragment size
75 * @fqdir: pointer to struct fqdir
76 * @rcu: rcu head for freeing deferall
77 */
78struct inet_frag_queue {
79 struct rhash_head node;
80 union {
81 struct frag_v4_compare_key v4;
82 struct frag_v6_compare_key v6;
83 } key;
84 struct timer_list timer;
85 spinlock_t lock;
86 refcount_t refcnt;
87 struct rb_root rb_fragments;
88 struct sk_buff *fragments_tail;
89 struct sk_buff *last_run_head;
90 ktime_t stamp;
91 int len;
92 int meat;
93 __u8 flags;
94 u16 max_size;
95 struct fqdir *fqdir;
96 struct rcu_head rcu;
97};
98
99struct inet_frags {
100 unsigned int qsize;
101
102 void (*constructor)(struct inet_frag_queue *q,
103 const void *arg);
104 void (*destructor)(struct inet_frag_queue *);
105 void (*frag_expire)(struct timer_list *t);
106 struct kmem_cache *frags_cachep;
107 const char *frags_cache_name;
108 struct rhashtable_params rhash_params;
109 refcount_t refcnt;
110 struct completion completion;
111};
112
113int inet_frags_init(struct inet_frags *);
114void inet_frags_fini(struct inet_frags *);
115
116int fqdir_init(struct fqdir **fqdirp, struct inet_frags *f, struct net *net);
117
118static inline void fqdir_pre_exit(struct fqdir *fqdir)
119{
120 fqdir->high_thresh = 0; /* prevent creation of new frags */
121 fqdir->dead = true;
122}
123void fqdir_exit(struct fqdir *fqdir);
124
125void inet_frag_kill(struct inet_frag_queue *q);
126void inet_frag_destroy(struct inet_frag_queue *q);
127struct inet_frag_queue *inet_frag_find(struct fqdir *fqdir, void *key);
128
129/* Free all skbs in the queue; return the sum of their truesizes. */
130unsigned int inet_frag_rbtree_purge(struct rb_root *root);
131
132static inline void inet_frag_put(struct inet_frag_queue *q)
133{
134 if (refcount_dec_and_test(&q->refcnt))
135 inet_frag_destroy(q);
136}
137
138/* Memory Tracking Functions. */
139
140static inline long frag_mem_limit(const struct fqdir *fqdir)
141{
142 return atomic_long_read(&fqdir->mem);
143}
144
145static inline void sub_frag_mem_limit(struct fqdir *fqdir, long val)
146{
147 atomic_long_sub(val, &fqdir->mem);
148}
149
150static inline void add_frag_mem_limit(struct fqdir *fqdir, long val)
151{
152 atomic_long_add(val, &fqdir->mem);
153}
154
155/* RFC 3168 support :
156 * We want to check ECN values of all fragments, do detect invalid combinations.
157 * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value.
158 */
159#define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */
160#define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */
161#define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */
162#define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */
163
164extern const u8 ip_frag_ecn_table[16];
165
166/* Return values of inet_frag_queue_insert() */
167#define IPFRAG_OK 0
168#define IPFRAG_DUP 1
169#define IPFRAG_OVERLAP 2
170int inet_frag_queue_insert(struct inet_frag_queue *q, struct sk_buff *skb,
171 int offset, int end);
172void *inet_frag_reasm_prepare(struct inet_frag_queue *q, struct sk_buff *skb,
173 struct sk_buff *parent);
174void inet_frag_reasm_finish(struct inet_frag_queue *q, struct sk_buff *head,
175 void *reasm_data, bool try_coalesce);
176struct sk_buff *inet_frag_pull_head(struct inet_frag_queue *q);
177
178#endif