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 struct nlattr *fc_encap; 55 u16 fc_encap_type; 56 }; 57 58 struct fib6_node { 59 struct fib6_node *parent; 60 struct fib6_node *left; 61 struct fib6_node *right; 62 #ifdef CONFIG_IPV6_SUBTREES 63 struct fib6_node *subtree; 64 #endif 65 struct rt6_info *leaf; 66 67 __u16 fn_bit; /* bit key */ 68 __u16 fn_flags; 69 int fn_sernum; 70 struct rt6_info *rr_ptr; 71 }; 72 73 #ifndef CONFIG_IPV6_SUBTREES 74 #define FIB6_SUBTREE(fn) NULL 75 #else 76 #define FIB6_SUBTREE(fn) ((fn)->subtree) 77 #endif 78 79 struct mx6_config { 80 const u32 *mx; 81 DECLARE_BITMAP(mx_valid, RTAX_MAX); 82 }; 83 84 /* 85 * routing information 86 * 87 */ 88 89 struct rt6key { 90 struct in6_addr addr; 91 int plen; 92 }; 93 94 struct fib6_table; 95 96 struct rt6_info { 97 struct dst_entry dst; 98 99 /* 100 * Tail elements of dst_entry (__refcnt etc.) 101 * and these elements (rarely used in hot path) are in 102 * the same cache line. 103 */ 104 struct fib6_table *rt6i_table; 105 struct fib6_node *rt6i_node; 106 107 struct in6_addr rt6i_gateway; 108 109 /* Multipath routes: 110 * siblings is a list of rt6_info that have the the same metric/weight, 111 * destination, but not the same gateway. nsiblings is just a cache 112 * to speed up lookup. 113 */ 114 struct list_head rt6i_siblings; 115 unsigned int rt6i_nsiblings; 116 117 atomic_t rt6i_ref; 118 119 /* These are in a separate cache line. */ 120 struct rt6key rt6i_dst ____cacheline_aligned_in_smp; 121 u32 rt6i_flags; 122 struct rt6key rt6i_src; 123 struct rt6key rt6i_prefsrc; 124 125 struct list_head rt6i_uncached; 126 struct uncached_list *rt6i_uncached_list; 127 128 struct inet6_dev *rt6i_idev; 129 struct rt6_info * __percpu *rt6i_pcpu; 130 131 u32 rt6i_metric; 132 u32 rt6i_pmtu; 133 /* more non-fragment space at head required */ 134 unsigned short rt6i_nfheader_len; 135 u8 rt6i_protocol; 136 }; 137 138 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst) 139 { 140 return ((struct rt6_info *)dst)->rt6i_idev; 141 } 142 143 static inline void rt6_clean_expires(struct rt6_info *rt) 144 { 145 rt->rt6i_flags &= ~RTF_EXPIRES; 146 rt->dst.expires = 0; 147 } 148 149 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires) 150 { 151 rt->dst.expires = expires; 152 rt->rt6i_flags |= RTF_EXPIRES; 153 } 154 155 static inline void rt6_update_expires(struct rt6_info *rt0, int timeout) 156 { 157 struct rt6_info *rt; 158 159 for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES); 160 rt = (struct rt6_info *)rt->dst.from); 161 if (rt && rt != rt0) 162 rt0->dst.expires = rt->dst.expires; 163 164 dst_set_expires(&rt0->dst, timeout); 165 rt0->rt6i_flags |= RTF_EXPIRES; 166 } 167 168 static inline u32 rt6_get_cookie(const struct rt6_info *rt) 169 { 170 if (rt->rt6i_flags & RTF_PCPU || 171 (unlikely(rt->dst.flags & DST_NOCACHE) && rt->dst.from)) 172 rt = (struct rt6_info *)(rt->dst.from); 173 174 return rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 175 } 176 177 static inline void ip6_rt_put(struct rt6_info *rt) 178 { 179 /* dst_release() accepts a NULL parameter. 180 * We rely on dst being first structure in struct rt6_info 181 */ 182 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0); 183 dst_release(&rt->dst); 184 } 185 186 enum fib6_walk_state { 187 #ifdef CONFIG_IPV6_SUBTREES 188 FWS_S, 189 #endif 190 FWS_L, 191 FWS_R, 192 FWS_C, 193 FWS_U 194 }; 195 196 struct fib6_walker { 197 struct list_head lh; 198 struct fib6_node *root, *node; 199 struct rt6_info *leaf; 200 enum fib6_walk_state state; 201 bool prune; 202 unsigned int skip; 203 unsigned int count; 204 int (*func)(struct fib6_walker *); 205 void *args; 206 }; 207 208 struct rt6_statistics { 209 __u32 fib_nodes; 210 __u32 fib_route_nodes; 211 __u32 fib_rt_alloc; /* permanent routes */ 212 __u32 fib_rt_entries; /* rt entries in table */ 213 __u32 fib_rt_cache; /* cache routes */ 214 __u32 fib_discarded_routes; 215 }; 216 217 #define RTN_TL_ROOT 0x0001 218 #define RTN_ROOT 0x0002 /* tree root node */ 219 #define RTN_RTINFO 0x0004 /* node with valid routing info */ 220 221 /* 222 * priority levels (or metrics) 223 * 224 */ 225 226 227 struct fib6_table { 228 struct hlist_node tb6_hlist; 229 u32 tb6_id; 230 rwlock_t tb6_lock; 231 struct fib6_node tb6_root; 232 struct inet_peer_base tb6_peers; 233 }; 234 235 #define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC 236 #define RT6_TABLE_MAIN RT_TABLE_MAIN 237 #define RT6_TABLE_DFLT RT6_TABLE_MAIN 238 #define RT6_TABLE_INFO RT6_TABLE_MAIN 239 #define RT6_TABLE_PREFIX RT6_TABLE_MAIN 240 241 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 242 #define FIB6_TABLE_MIN 1 243 #define FIB6_TABLE_MAX RT_TABLE_MAX 244 #define RT6_TABLE_LOCAL RT_TABLE_LOCAL 245 #else 246 #define FIB6_TABLE_MIN RT_TABLE_MAIN 247 #define FIB6_TABLE_MAX FIB6_TABLE_MIN 248 #define RT6_TABLE_LOCAL RT6_TABLE_MAIN 249 #endif 250 251 typedef struct rt6_info *(*pol_lookup_t)(struct net *, 252 struct fib6_table *, 253 struct flowi6 *, int); 254 255 /* 256 * exported functions 257 */ 258 259 struct fib6_table *fib6_get_table(struct net *net, u32 id); 260 struct fib6_table *fib6_new_table(struct net *net, u32 id); 261 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, 262 int flags, pol_lookup_t lookup); 263 264 struct fib6_node *fib6_lookup(struct fib6_node *root, 265 const struct in6_addr *daddr, 266 const struct in6_addr *saddr); 267 268 struct fib6_node *fib6_locate(struct fib6_node *root, 269 const struct in6_addr *daddr, int dst_len, 270 const struct in6_addr *saddr, int src_len); 271 272 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 273 void *arg); 274 275 int fib6_add(struct fib6_node *root, struct rt6_info *rt, 276 struct nl_info *info, struct mx6_config *mxc); 277 int fib6_del(struct rt6_info *rt, struct nl_info *info); 278 279 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info, 280 unsigned int flags); 281 282 void fib6_run_gc(unsigned long expires, struct net *net, bool force); 283 284 void fib6_gc_cleanup(void); 285 286 int fib6_init(void); 287 288 int ipv6_route_open(struct inode *inode, struct file *file); 289 290 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 291 int fib6_rules_init(void); 292 void fib6_rules_cleanup(void); 293 #else 294 static inline int fib6_rules_init(void) 295 { 296 return 0; 297 } 298 static inline void fib6_rules_cleanup(void) 299 { 300 return ; 301 } 302 #endif 303 #endif 304