1 /* 2 * Linux INET6 implementation 3 * 4 * Authors: 5 * Pedro Roque <roque@di.fc.ul.pt> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #ifndef _IP6_FIB_H 14 #define _IP6_FIB_H 15 16 #include <linux/ipv6_route.h> 17 #include <linux/rtnetlink.h> 18 #include <linux/spinlock.h> 19 #include <net/dst.h> 20 #include <net/flow.h> 21 #include <net/netlink.h> 22 #include <net/inetpeer.h> 23 24 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 25 #define FIB6_TABLE_HASHSZ 256 26 #else 27 #define FIB6_TABLE_HASHSZ 1 28 #endif 29 30 struct rt6_info; 31 32 struct fib6_config { 33 u32 fc_table; 34 u32 fc_metric; 35 int fc_dst_len; 36 int fc_src_len; 37 int fc_ifindex; 38 u32 fc_flags; 39 u32 fc_protocol; 40 u32 fc_type; /* only 8 bits are used */ 41 42 struct in6_addr fc_dst; 43 struct in6_addr fc_src; 44 struct in6_addr fc_prefsrc; 45 struct in6_addr fc_gateway; 46 47 unsigned long fc_expires; 48 struct nlattr *fc_mx; 49 int fc_mx_len; 50 int fc_mp_len; 51 struct nlattr *fc_mp; 52 53 struct nl_info fc_nlinfo; 54 }; 55 56 struct fib6_node { 57 struct fib6_node *parent; 58 struct fib6_node *left; 59 struct fib6_node *right; 60 #ifdef CONFIG_IPV6_SUBTREES 61 struct fib6_node *subtree; 62 #endif 63 struct rt6_info *leaf; 64 65 __u16 fn_bit; /* bit key */ 66 __u16 fn_flags; 67 int fn_sernum; 68 struct rt6_info *rr_ptr; 69 }; 70 71 #ifndef CONFIG_IPV6_SUBTREES 72 #define FIB6_SUBTREE(fn) NULL 73 #else 74 #define FIB6_SUBTREE(fn) ((fn)->subtree) 75 #endif 76 77 struct mx6_config { 78 const u32 *mx; 79 DECLARE_BITMAP(mx_valid, RTAX_MAX); 80 }; 81 82 /* 83 * routing information 84 * 85 */ 86 87 struct rt6key { 88 struct in6_addr addr; 89 int plen; 90 }; 91 92 struct fib6_table; 93 94 struct rt6_info { 95 struct dst_entry dst; 96 97 /* 98 * Tail elements of dst_entry (__refcnt etc.) 99 * and these elements (rarely used in hot path) are in 100 * the same cache line. 101 */ 102 struct fib6_table *rt6i_table; 103 struct fib6_node *rt6i_node; 104 105 struct in6_addr rt6i_gateway; 106 107 /* Multipath routes: 108 * siblings is a list of rt6_info that have the the same metric/weight, 109 * destination, but not the same gateway. nsiblings is just a cache 110 * to speed up lookup. 111 */ 112 struct list_head rt6i_siblings; 113 unsigned int rt6i_nsiblings; 114 115 atomic_t rt6i_ref; 116 117 /* These are in a separate cache line. */ 118 struct rt6key rt6i_dst ____cacheline_aligned_in_smp; 119 u32 rt6i_flags; 120 struct rt6key rt6i_src; 121 struct rt6key rt6i_prefsrc; 122 123 struct list_head rt6i_uncached; 124 struct uncached_list *rt6i_uncached_list; 125 126 struct inet6_dev *rt6i_idev; 127 struct rt6_info * __percpu *rt6i_pcpu; 128 129 u32 rt6i_metric; 130 u32 rt6i_pmtu; 131 /* more non-fragment space at head required */ 132 unsigned short rt6i_nfheader_len; 133 u8 rt6i_protocol; 134 }; 135 136 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst) 137 { 138 return ((struct rt6_info *)dst)->rt6i_idev; 139 } 140 141 static inline void rt6_clean_expires(struct rt6_info *rt) 142 { 143 rt->rt6i_flags &= ~RTF_EXPIRES; 144 rt->dst.expires = 0; 145 } 146 147 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires) 148 { 149 rt->dst.expires = expires; 150 rt->rt6i_flags |= RTF_EXPIRES; 151 } 152 153 static inline void rt6_update_expires(struct rt6_info *rt0, int timeout) 154 { 155 struct rt6_info *rt; 156 157 for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES); 158 rt = (struct rt6_info *)rt->dst.from); 159 if (rt && rt != rt0) 160 rt0->dst.expires = rt->dst.expires; 161 162 dst_set_expires(&rt0->dst, timeout); 163 rt0->rt6i_flags |= RTF_EXPIRES; 164 } 165 166 static inline u32 rt6_get_cookie(const struct rt6_info *rt) 167 { 168 if (rt->rt6i_flags & RTF_PCPU || unlikely(rt->dst.flags & DST_NOCACHE)) 169 rt = (struct rt6_info *)(rt->dst.from); 170 171 return rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 172 } 173 174 static inline void ip6_rt_put(struct rt6_info *rt) 175 { 176 /* dst_release() accepts a NULL parameter. 177 * We rely on dst being first structure in struct rt6_info 178 */ 179 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0); 180 dst_release(&rt->dst); 181 } 182 183 enum fib6_walk_state { 184 #ifdef CONFIG_IPV6_SUBTREES 185 FWS_S, 186 #endif 187 FWS_L, 188 FWS_R, 189 FWS_C, 190 FWS_U 191 }; 192 193 struct fib6_walker { 194 struct list_head lh; 195 struct fib6_node *root, *node; 196 struct rt6_info *leaf; 197 enum fib6_walk_state state; 198 bool prune; 199 unsigned int skip; 200 unsigned int count; 201 int (*func)(struct fib6_walker *); 202 void *args; 203 }; 204 205 struct rt6_statistics { 206 __u32 fib_nodes; 207 __u32 fib_route_nodes; 208 __u32 fib_rt_alloc; /* permanent routes */ 209 __u32 fib_rt_entries; /* rt entries in table */ 210 __u32 fib_rt_cache; /* cache routes */ 211 __u32 fib_discarded_routes; 212 }; 213 214 #define RTN_TL_ROOT 0x0001 215 #define RTN_ROOT 0x0002 /* tree root node */ 216 #define RTN_RTINFO 0x0004 /* node with valid routing info */ 217 218 /* 219 * priority levels (or metrics) 220 * 221 */ 222 223 224 struct fib6_table { 225 struct hlist_node tb6_hlist; 226 u32 tb6_id; 227 rwlock_t tb6_lock; 228 struct fib6_node tb6_root; 229 struct inet_peer_base tb6_peers; 230 }; 231 232 #define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC 233 #define RT6_TABLE_MAIN RT_TABLE_MAIN 234 #define RT6_TABLE_DFLT RT6_TABLE_MAIN 235 #define RT6_TABLE_INFO RT6_TABLE_MAIN 236 #define RT6_TABLE_PREFIX RT6_TABLE_MAIN 237 238 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 239 #define FIB6_TABLE_MIN 1 240 #define FIB6_TABLE_MAX RT_TABLE_MAX 241 #define RT6_TABLE_LOCAL RT_TABLE_LOCAL 242 #else 243 #define FIB6_TABLE_MIN RT_TABLE_MAIN 244 #define FIB6_TABLE_MAX FIB6_TABLE_MIN 245 #define RT6_TABLE_LOCAL RT6_TABLE_MAIN 246 #endif 247 248 typedef struct rt6_info *(*pol_lookup_t)(struct net *, 249 struct fib6_table *, 250 struct flowi6 *, int); 251 252 /* 253 * exported functions 254 */ 255 256 struct fib6_table *fib6_get_table(struct net *net, u32 id); 257 struct fib6_table *fib6_new_table(struct net *net, u32 id); 258 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, 259 int flags, pol_lookup_t lookup); 260 261 struct fib6_node *fib6_lookup(struct fib6_node *root, 262 const struct in6_addr *daddr, 263 const struct in6_addr *saddr); 264 265 struct fib6_node *fib6_locate(struct fib6_node *root, 266 const struct in6_addr *daddr, int dst_len, 267 const struct in6_addr *saddr, int src_len); 268 269 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 270 void *arg); 271 272 int fib6_add(struct fib6_node *root, struct rt6_info *rt, 273 struct nl_info *info, struct mx6_config *mxc); 274 int fib6_del(struct rt6_info *rt, struct nl_info *info); 275 276 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info); 277 278 void fib6_run_gc(unsigned long expires, struct net *net, bool force); 279 280 void fib6_gc_cleanup(void); 281 282 int fib6_init(void); 283 284 int ipv6_route_open(struct inode *inode, struct file *file); 285 286 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 287 int fib6_rules_init(void); 288 void fib6_rules_cleanup(void); 289 #else 290 static inline int fib6_rules_init(void) 291 { 292 return 0; 293 } 294 static inline void fib6_rules_cleanup(void) 295 { 296 return ; 297 } 298 #endif 299 #endif 300