1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * INETPEER - A storage for permanent information about peers 4 * 5 * Authors: Andrey V. Savochkin <saw@msu.ru> 6 */ 7 8 #ifndef _NET_INETPEER_H 9 #define _NET_INETPEER_H 10 11 #include <linux/types.h> 12 #include <linux/init.h> 13 #include <linux/jiffies.h> 14 #include <linux/spinlock.h> 15 #include <linux/rtnetlink.h> 16 #include <net/ipv6.h> 17 #include <linux/atomic.h> 18 19 /* IPv4 address key for cache lookups */ 20 struct ipv4_addr_key { 21 __be32 addr; 22 int vif; 23 }; 24 25 #define INETPEER_MAXKEYSZ (sizeof(struct in6_addr) / sizeof(u32)) 26 27 struct inetpeer_addr { 28 union { 29 struct ipv4_addr_key a4; 30 struct in6_addr a6; 31 u32 key[INETPEER_MAXKEYSZ]; 32 }; 33 __u16 family; 34 }; 35 36 struct inet_peer { 37 struct rb_node rb_node; 38 u64 hash; 39 struct inetpeer_addr daddr; 40 41 u32 metrics[RTAX_MAX]; 42 u32 rate_tokens; /* rate limiting for ICMP */ 43 u32 n_redirects; 44 unsigned long rate_last; 45 /* 46 * Once inet_peer is queued for deletion (refcnt == 0), following field 47 * is not available: rid 48 * We can share memory with rcu_head to help keep inet_peer small. 49 */ 50 union { 51 struct { 52 atomic_t rid; /* Frag reception counter */ 53 }; 54 struct rcu_head rcu; 55 }; 56 57 /* following fields might be frequently dirtied */ 58 __u32 dtime; /* the time of last use of not referenced entries */ 59 refcount_t refcnt; 60 }; 61 62 struct inet_peer_base { 63 struct rb_root rb_root; 64 seqlock_t lock; 65 int total; 66 }; 67 68 void inet_peer_base_init(struct inet_peer_base *); 69 70 void inet_initpeers(void) __init; 71 72 #define INETPEER_METRICS_NEW (~(u32) 0) 73 74 static inline void inetpeer_set_addr_v4(struct inetpeer_addr *iaddr, __be32 ip) 75 { 76 iaddr->a4.addr = ip; 77 iaddr->a4.vif = 0; 78 iaddr->family = AF_INET; 79 } 80 81 static inline __be32 inetpeer_get_addr_v4(struct inetpeer_addr *iaddr) 82 { 83 return iaddr->a4.addr; 84 } 85 86 static inline void inetpeer_set_addr_v6(struct inetpeer_addr *iaddr, 87 struct in6_addr *in6) 88 { 89 iaddr->a6 = *in6; 90 iaddr->family = AF_INET6; 91 } 92 93 static inline struct in6_addr *inetpeer_get_addr_v6(struct inetpeer_addr *iaddr) 94 { 95 return &iaddr->a6; 96 } 97 98 /* can be called with or without local BH being disabled */ 99 struct inet_peer *inet_getpeer(struct inet_peer_base *base, 100 const struct inetpeer_addr *daddr); 101 102 static inline struct inet_peer *inet_getpeer_v4(struct inet_peer_base *base, 103 __be32 v4daddr, 104 int vif) 105 { 106 struct inetpeer_addr daddr; 107 108 daddr.a4.addr = v4daddr; 109 daddr.a4.vif = vif; 110 daddr.family = AF_INET; 111 return inet_getpeer(base, &daddr); 112 } 113 114 static inline struct inet_peer *inet_getpeer_v6(struct inet_peer_base *base, 115 const struct in6_addr *v6daddr) 116 { 117 struct inetpeer_addr daddr; 118 119 daddr.a6 = *v6daddr; 120 daddr.family = AF_INET6; 121 return inet_getpeer(base, &daddr); 122 } 123 124 static inline int inetpeer_addr_cmp(const struct inetpeer_addr *a, 125 const struct inetpeer_addr *b) 126 { 127 int i, n; 128 129 if (a->family != b->family) 130 return a->family < b->family ? -1 : 1; 131 132 if (a->family == AF_INET) 133 n = sizeof(a->a4) / sizeof(u32); 134 else 135 n = sizeof(a->a6) / sizeof(u32); 136 137 for (i = 0; i < n; i++) { 138 if (a->key[i] == b->key[i]) 139 continue; 140 if (a->key[i] < b->key[i]) 141 return -1; 142 return 1; 143 } 144 145 return 0; 146 } 147 148 /* can be called from BH context or outside */ 149 void inet_putpeer(struct inet_peer *p); 150 bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout); 151 152 void inetpeer_invalidate_tree(struct inet_peer_base *); 153 154 #endif /* _NET_INETPEER_H */ 155