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 u16 fc_type; /* only 8 bits are used */ 41 u16 fc_delete_all_nh : 1, 42 __unused : 15; 43 44 struct in6_addr fc_dst; 45 struct in6_addr fc_src; 46 struct in6_addr fc_prefsrc; 47 struct in6_addr fc_gateway; 48 49 unsigned long fc_expires; 50 struct nlattr *fc_mx; 51 int fc_mx_len; 52 int fc_mp_len; 53 struct nlattr *fc_mp; 54 55 struct nl_info fc_nlinfo; 56 struct nlattr *fc_encap; 57 u16 fc_encap_type; 58 }; 59 60 struct fib6_node { 61 struct fib6_node *parent; 62 struct fib6_node *left; 63 struct fib6_node *right; 64 #ifdef CONFIG_IPV6_SUBTREES 65 struct fib6_node *subtree; 66 #endif 67 struct rt6_info *leaf; 68 69 __u16 fn_bit; /* bit key */ 70 __u16 fn_flags; 71 int fn_sernum; 72 struct rt6_info *rr_ptr; 73 }; 74 75 #ifndef CONFIG_IPV6_SUBTREES 76 #define FIB6_SUBTREE(fn) NULL 77 #else 78 #define FIB6_SUBTREE(fn) ((fn)->subtree) 79 #endif 80 81 struct mx6_config { 82 const u32 *mx; 83 DECLARE_BITMAP(mx_valid, RTAX_MAX); 84 }; 85 86 /* 87 * routing information 88 * 89 */ 90 91 struct rt6key { 92 struct in6_addr addr; 93 int plen; 94 }; 95 96 struct fib6_table; 97 98 struct rt6_info { 99 struct dst_entry dst; 100 101 /* 102 * Tail elements of dst_entry (__refcnt etc.) 103 * and these elements (rarely used in hot path) are in 104 * the same cache line. 105 */ 106 struct fib6_table *rt6i_table; 107 struct fib6_node *rt6i_node; 108 109 struct in6_addr rt6i_gateway; 110 111 /* Multipath routes: 112 * siblings is a list of rt6_info that have the the same metric/weight, 113 * destination, but not the same gateway. nsiblings is just a cache 114 * to speed up lookup. 115 */ 116 struct list_head rt6i_siblings; 117 unsigned int rt6i_nsiblings; 118 119 atomic_t rt6i_ref; 120 121 /* These are in a separate cache line. */ 122 struct rt6key rt6i_dst ____cacheline_aligned_in_smp; 123 u32 rt6i_flags; 124 struct rt6key rt6i_src; 125 struct rt6key rt6i_prefsrc; 126 127 struct list_head rt6i_uncached; 128 struct uncached_list *rt6i_uncached_list; 129 130 struct inet6_dev *rt6i_idev; 131 struct rt6_info * __percpu *rt6i_pcpu; 132 133 u32 rt6i_metric; 134 u32 rt6i_pmtu; 135 /* more non-fragment space at head required */ 136 unsigned short rt6i_nfheader_len; 137 u8 rt6i_protocol; 138 }; 139 140 static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst) 141 { 142 return ((struct rt6_info *)dst)->rt6i_idev; 143 } 144 145 static inline void rt6_clean_expires(struct rt6_info *rt) 146 { 147 rt->rt6i_flags &= ~RTF_EXPIRES; 148 rt->dst.expires = 0; 149 } 150 151 static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires) 152 { 153 rt->dst.expires = expires; 154 rt->rt6i_flags |= RTF_EXPIRES; 155 } 156 157 static inline void rt6_update_expires(struct rt6_info *rt0, int timeout) 158 { 159 struct rt6_info *rt; 160 161 for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES); 162 rt = (struct rt6_info *)rt->dst.from); 163 if (rt && rt != rt0) 164 rt0->dst.expires = rt->dst.expires; 165 166 dst_set_expires(&rt0->dst, timeout); 167 rt0->rt6i_flags |= RTF_EXPIRES; 168 } 169 170 static inline u32 rt6_get_cookie(const struct rt6_info *rt) 171 { 172 if (rt->rt6i_flags & RTF_PCPU || 173 (unlikely(!list_empty(&rt->rt6i_uncached)) && rt->dst.from)) 174 rt = (struct rt6_info *)(rt->dst.from); 175 176 return rt->rt6i_node ? rt->rt6i_node->fn_sernum : 0; 177 } 178 179 static inline void ip6_rt_put(struct rt6_info *rt) 180 { 181 /* dst_release() accepts a NULL parameter. 182 * We rely on dst being first structure in struct rt6_info 183 */ 184 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0); 185 dst_release(&rt->dst); 186 } 187 188 enum fib6_walk_state { 189 #ifdef CONFIG_IPV6_SUBTREES 190 FWS_S, 191 #endif 192 FWS_L, 193 FWS_R, 194 FWS_C, 195 FWS_U 196 }; 197 198 struct fib6_walker { 199 struct list_head lh; 200 struct fib6_node *root, *node; 201 struct rt6_info *leaf; 202 enum fib6_walk_state state; 203 bool prune; 204 unsigned int skip; 205 unsigned int count; 206 int (*func)(struct fib6_walker *); 207 void *args; 208 }; 209 210 struct rt6_statistics { 211 __u32 fib_nodes; 212 __u32 fib_route_nodes; 213 __u32 fib_rt_alloc; /* permanent routes */ 214 __u32 fib_rt_entries; /* rt entries in table */ 215 __u32 fib_rt_cache; /* cache routes */ 216 __u32 fib_discarded_routes; 217 }; 218 219 #define RTN_TL_ROOT 0x0001 220 #define RTN_ROOT 0x0002 /* tree root node */ 221 #define RTN_RTINFO 0x0004 /* node with valid routing info */ 222 223 /* 224 * priority levels (or metrics) 225 * 226 */ 227 228 229 struct fib6_table { 230 struct hlist_node tb6_hlist; 231 u32 tb6_id; 232 rwlock_t tb6_lock; 233 struct fib6_node tb6_root; 234 struct inet_peer_base tb6_peers; 235 unsigned int flags; 236 #define RT6_TABLE_HAS_DFLT_ROUTER BIT(0) 237 }; 238 239 #define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC 240 #define RT6_TABLE_MAIN RT_TABLE_MAIN 241 #define RT6_TABLE_DFLT RT6_TABLE_MAIN 242 #define RT6_TABLE_INFO RT6_TABLE_MAIN 243 #define RT6_TABLE_PREFIX RT6_TABLE_MAIN 244 245 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 246 #define FIB6_TABLE_MIN 1 247 #define FIB6_TABLE_MAX RT_TABLE_MAX 248 #define RT6_TABLE_LOCAL RT_TABLE_LOCAL 249 #else 250 #define FIB6_TABLE_MIN RT_TABLE_MAIN 251 #define FIB6_TABLE_MAX FIB6_TABLE_MIN 252 #define RT6_TABLE_LOCAL RT6_TABLE_MAIN 253 #endif 254 255 typedef struct rt6_info *(*pol_lookup_t)(struct net *, 256 struct fib6_table *, 257 struct flowi6 *, int); 258 259 /* 260 * exported functions 261 */ 262 263 struct fib6_table *fib6_get_table(struct net *net, u32 id); 264 struct fib6_table *fib6_new_table(struct net *net, u32 id); 265 struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6, 266 int flags, pol_lookup_t lookup); 267 268 struct fib6_node *fib6_lookup(struct fib6_node *root, 269 const struct in6_addr *daddr, 270 const struct in6_addr *saddr); 271 272 struct fib6_node *fib6_locate(struct fib6_node *root, 273 const struct in6_addr *daddr, int dst_len, 274 const struct in6_addr *saddr, int src_len); 275 276 void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg), 277 void *arg); 278 279 int fib6_add(struct fib6_node *root, struct rt6_info *rt, 280 struct nl_info *info, struct mx6_config *mxc, 281 struct netlink_ext_ack *extack); 282 int fib6_del(struct rt6_info *rt, struct nl_info *info); 283 284 void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info, 285 unsigned int flags); 286 287 void fib6_run_gc(unsigned long expires, struct net *net, bool force); 288 289 void fib6_gc_cleanup(void); 290 291 int fib6_init(void); 292 293 int ipv6_route_open(struct inode *inode, struct file *file); 294 295 #ifdef CONFIG_IPV6_MULTIPLE_TABLES 296 int fib6_rules_init(void); 297 void fib6_rules_cleanup(void); 298 #else 299 static inline int fib6_rules_init(void) 300 { 301 return 0; 302 } 303 static inline void fib6_rules_cleanup(void) 304 { 305 return ; 306 } 307 #endif 308 #endif 309