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 7 struct 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 */ 28 enum { 29 INET_FRAG_FIRST_IN = BIT(0), 30 INET_FRAG_LAST_IN = BIT(1), 31 INET_FRAG_COMPLETE = BIT(2), 32 }; 33 34 struct frag_v4_compare_key { 35 __be32 saddr; 36 __be32 daddr; 37 u32 user; 38 u32 vif; 39 __be16 id; 40 u16 protocol; 41 }; 42 43 struct 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 * @rb_fragments: received fragments rb-tree root 61 * @fragments_tail: received fragments tail 62 * @last_run_head: the head of the last "run". see ip_fragment.c 63 * @stamp: timestamp of the last received fragment 64 * @len: total length of the original datagram 65 * @meat: length of received fragments so far 66 * @flags: fragment queue flags 67 * @max_size: maximum received fragment size 68 * @net: namespace that this frag belongs to 69 * @rcu: rcu head for freeing deferall 70 */ 71 struct inet_frag_queue { 72 struct rhash_head node; 73 union { 74 struct frag_v4_compare_key v4; 75 struct frag_v6_compare_key v6; 76 } key; 77 struct timer_list timer; 78 spinlock_t lock; 79 refcount_t refcnt; 80 struct sk_buff *fragments; /* Used in IPv6. */ 81 struct rb_root rb_fragments; /* Used in IPv4. */ 82 struct sk_buff *fragments_tail; 83 struct sk_buff *last_run_head; 84 ktime_t stamp; 85 int len; 86 int meat; 87 __u8 flags; 88 u16 max_size; 89 struct netns_frags *net; 90 struct rcu_head rcu; 91 }; 92 93 struct inet_frags { 94 unsigned int qsize; 95 96 void (*constructor)(struct inet_frag_queue *q, 97 const void *arg); 98 void (*destructor)(struct inet_frag_queue *); 99 void (*frag_expire)(struct timer_list *t); 100 struct kmem_cache *frags_cachep; 101 const char *frags_cache_name; 102 struct rhashtable_params rhash_params; 103 }; 104 105 int inet_frags_init(struct inet_frags *); 106 void inet_frags_fini(struct inet_frags *); 107 108 static inline int inet_frags_init_net(struct netns_frags *nf) 109 { 110 atomic_long_set(&nf->mem, 0); 111 return rhashtable_init(&nf->rhashtable, &nf->f->rhash_params); 112 } 113 void inet_frags_exit_net(struct netns_frags *nf); 114 115 void inet_frag_kill(struct inet_frag_queue *q); 116 void inet_frag_destroy(struct inet_frag_queue *q); 117 struct inet_frag_queue *inet_frag_find(struct netns_frags *nf, void *key); 118 119 /* Free all skbs in the queue; return the sum of their truesizes. */ 120 unsigned int inet_frag_rbtree_purge(struct rb_root *root); 121 122 static inline void inet_frag_put(struct inet_frag_queue *q) 123 { 124 if (refcount_dec_and_test(&q->refcnt)) 125 inet_frag_destroy(q); 126 } 127 128 /* Memory Tracking Functions. */ 129 130 static inline long frag_mem_limit(const struct netns_frags *nf) 131 { 132 return atomic_long_read(&nf->mem); 133 } 134 135 static inline void sub_frag_mem_limit(struct netns_frags *nf, long val) 136 { 137 atomic_long_sub(val, &nf->mem); 138 } 139 140 static inline void add_frag_mem_limit(struct netns_frags *nf, long val) 141 { 142 atomic_long_add(val, &nf->mem); 143 } 144 145 /* RFC 3168 support : 146 * We want to check ECN values of all fragments, do detect invalid combinations. 147 * In ipq->ecn, we store the OR value of each ip4_frag_ecn() fragment value. 148 */ 149 #define IPFRAG_ECN_NOT_ECT 0x01 /* one frag had ECN_NOT_ECT */ 150 #define IPFRAG_ECN_ECT_1 0x02 /* one frag had ECN_ECT_1 */ 151 #define IPFRAG_ECN_ECT_0 0x04 /* one frag had ECN_ECT_0 */ 152 #define IPFRAG_ECN_CE 0x08 /* one frag had ECN_CE */ 153 154 extern const u8 ip_frag_ecn_table[16]; 155 156 #endif 157