Loading...
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 <linux/notifier.h>
20#include <net/dst.h>
21#include <net/flow.h>
22#include <net/netlink.h>
23#include <net/inetpeer.h>
24#include <net/fib_notifier.h>
25
26#ifdef CONFIG_IPV6_MULTIPLE_TABLES
27#define FIB6_TABLE_HASHSZ 256
28#else
29#define FIB6_TABLE_HASHSZ 1
30#endif
31
32#define RT6_DEBUG 2
33
34#if RT6_DEBUG >= 3
35#define RT6_TRACE(x...) pr_debug(x)
36#else
37#define RT6_TRACE(x...) do { ; } while (0)
38#endif
39
40struct rt6_info;
41
42struct fib6_config {
43 u32 fc_table;
44 u32 fc_metric;
45 int fc_dst_len;
46 int fc_src_len;
47 int fc_ifindex;
48 u32 fc_flags;
49 u32 fc_protocol;
50 u16 fc_type; /* only 8 bits are used */
51 u16 fc_delete_all_nh : 1,
52 __unused : 15;
53
54 struct in6_addr fc_dst;
55 struct in6_addr fc_src;
56 struct in6_addr fc_prefsrc;
57 struct in6_addr fc_gateway;
58
59 unsigned long fc_expires;
60 struct nlattr *fc_mx;
61 int fc_mx_len;
62 int fc_mp_len;
63 struct nlattr *fc_mp;
64
65 struct nl_info fc_nlinfo;
66 struct nlattr *fc_encap;
67 u16 fc_encap_type;
68};
69
70struct fib6_node {
71 struct fib6_node __rcu *parent;
72 struct fib6_node __rcu *left;
73 struct fib6_node __rcu *right;
74#ifdef CONFIG_IPV6_SUBTREES
75 struct fib6_node __rcu *subtree;
76#endif
77 struct rt6_info __rcu *leaf;
78
79 __u16 fn_bit; /* bit key */
80 __u16 fn_flags;
81 int fn_sernum;
82 struct rt6_info __rcu *rr_ptr;
83 struct rcu_head rcu;
84};
85
86struct fib6_gc_args {
87 int timeout;
88 int more;
89};
90
91#ifndef CONFIG_IPV6_SUBTREES
92#define FIB6_SUBTREE(fn) NULL
93#else
94#define FIB6_SUBTREE(fn) (rcu_dereference_protected((fn)->subtree, 1))
95#endif
96
97struct mx6_config {
98 const u32 *mx;
99 DECLARE_BITMAP(mx_valid, RTAX_MAX);
100};
101
102/*
103 * routing information
104 *
105 */
106
107struct rt6key {
108 struct in6_addr addr;
109 int plen;
110};
111
112struct fib6_table;
113
114struct rt6_exception_bucket {
115 struct hlist_head chain;
116 int depth;
117};
118
119struct rt6_exception {
120 struct hlist_node hlist;
121 struct rt6_info *rt6i;
122 unsigned long stamp;
123 struct rcu_head rcu;
124};
125
126#define FIB6_EXCEPTION_BUCKET_SIZE_SHIFT 10
127#define FIB6_EXCEPTION_BUCKET_SIZE (1 << FIB6_EXCEPTION_BUCKET_SIZE_SHIFT)
128#define FIB6_MAX_DEPTH 5
129
130struct rt6_info {
131 struct dst_entry dst;
132 struct rt6_info __rcu *rt6_next;
133 struct rt6_info *from;
134
135 /*
136 * Tail elements of dst_entry (__refcnt etc.)
137 * and these elements (rarely used in hot path) are in
138 * the same cache line.
139 */
140 struct fib6_table *rt6i_table;
141 struct fib6_node __rcu *rt6i_node;
142
143 struct in6_addr rt6i_gateway;
144
145 /* Multipath routes:
146 * siblings is a list of rt6_info that have the the same metric/weight,
147 * destination, but not the same gateway. nsiblings is just a cache
148 * to speed up lookup.
149 */
150 struct list_head rt6i_siblings;
151 unsigned int rt6i_nsiblings;
152 atomic_t rt6i_nh_upper_bound;
153
154 atomic_t rt6i_ref;
155
156 unsigned int rt6i_nh_flags;
157
158 /* These are in a separate cache line. */
159 struct rt6key rt6i_dst ____cacheline_aligned_in_smp;
160 u32 rt6i_flags;
161 struct rt6key rt6i_src;
162 struct rt6key rt6i_prefsrc;
163
164 struct list_head rt6i_uncached;
165 struct uncached_list *rt6i_uncached_list;
166
167 struct inet6_dev *rt6i_idev;
168 struct rt6_info * __percpu *rt6i_pcpu;
169 struct rt6_exception_bucket __rcu *rt6i_exception_bucket;
170
171 u32 rt6i_metric;
172 u32 rt6i_pmtu;
173 /* more non-fragment space at head required */
174 int rt6i_nh_weight;
175 unsigned short rt6i_nfheader_len;
176 u8 rt6i_protocol;
177 u8 exception_bucket_flushed:1,
178 should_flush:1,
179 unused:6;
180};
181
182#define for_each_fib6_node_rt_rcu(fn) \
183 for (rt = rcu_dereference((fn)->leaf); rt; \
184 rt = rcu_dereference(rt->rt6_next))
185
186#define for_each_fib6_walker_rt(w) \
187 for (rt = (w)->leaf; rt; \
188 rt = rcu_dereference_protected(rt->rt6_next, 1))
189
190static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
191{
192 return ((struct rt6_info *)dst)->rt6i_idev;
193}
194
195static inline void rt6_clean_expires(struct rt6_info *rt)
196{
197 rt->rt6i_flags &= ~RTF_EXPIRES;
198 rt->dst.expires = 0;
199}
200
201static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
202{
203 rt->dst.expires = expires;
204 rt->rt6i_flags |= RTF_EXPIRES;
205}
206
207static inline void rt6_update_expires(struct rt6_info *rt0, int timeout)
208{
209 struct rt6_info *rt;
210
211 for (rt = rt0; rt && !(rt->rt6i_flags & RTF_EXPIRES); rt = rt->from);
212 if (rt && rt != rt0)
213 rt0->dst.expires = rt->dst.expires;
214 dst_set_expires(&rt0->dst, timeout);
215 rt0->rt6i_flags |= RTF_EXPIRES;
216}
217
218/* Function to safely get fn->sernum for passed in rt
219 * and store result in passed in cookie.
220 * Return true if we can get cookie safely
221 * Return false if not
222 */
223static inline bool rt6_get_cookie_safe(const struct rt6_info *rt,
224 u32 *cookie)
225{
226 struct fib6_node *fn;
227 bool status = false;
228
229 rcu_read_lock();
230 fn = rcu_dereference(rt->rt6i_node);
231
232 if (fn) {
233 *cookie = fn->fn_sernum;
234 /* pairs with smp_wmb() in fib6_update_sernum_upto_root() */
235 smp_rmb();
236 status = true;
237 }
238
239 rcu_read_unlock();
240 return status;
241}
242
243static inline u32 rt6_get_cookie(const struct rt6_info *rt)
244{
245 u32 cookie = 0;
246
247 if (rt->rt6i_flags & RTF_PCPU ||
248 (unlikely(!list_empty(&rt->rt6i_uncached)) && rt->from))
249 rt = rt->from;
250
251 rt6_get_cookie_safe(rt, &cookie);
252
253 return cookie;
254}
255
256static inline void ip6_rt_put(struct rt6_info *rt)
257{
258 /* dst_release() accepts a NULL parameter.
259 * We rely on dst being first structure in struct rt6_info
260 */
261 BUILD_BUG_ON(offsetof(struct rt6_info, dst) != 0);
262 dst_release(&rt->dst);
263}
264
265void rt6_free_pcpu(struct rt6_info *non_pcpu_rt);
266
267static inline void rt6_hold(struct rt6_info *rt)
268{
269 atomic_inc(&rt->rt6i_ref);
270}
271
272static inline void rt6_release(struct rt6_info *rt)
273{
274 if (atomic_dec_and_test(&rt->rt6i_ref)) {
275 rt6_free_pcpu(rt);
276 dst_dev_put(&rt->dst);
277 dst_release(&rt->dst);
278 }
279}
280
281enum fib6_walk_state {
282#ifdef CONFIG_IPV6_SUBTREES
283 FWS_S,
284#endif
285 FWS_L,
286 FWS_R,
287 FWS_C,
288 FWS_U
289};
290
291struct fib6_walker {
292 struct list_head lh;
293 struct fib6_node *root, *node;
294 struct rt6_info *leaf;
295 enum fib6_walk_state state;
296 unsigned int skip;
297 unsigned int count;
298 int (*func)(struct fib6_walker *);
299 void *args;
300};
301
302struct rt6_statistics {
303 __u32 fib_nodes; /* all fib6 nodes */
304 __u32 fib_route_nodes; /* intermediate nodes */
305 __u32 fib_rt_entries; /* rt entries in fib table */
306 __u32 fib_rt_cache; /* cached rt entries in exception table */
307 __u32 fib_discarded_routes; /* total number of routes delete */
308
309 /* The following stats are not protected by any lock */
310 atomic_t fib_rt_alloc; /* total number of routes alloced */
311 atomic_t fib_rt_uncache; /* rt entries in uncached list */
312};
313
314#define RTN_TL_ROOT 0x0001
315#define RTN_ROOT 0x0002 /* tree root node */
316#define RTN_RTINFO 0x0004 /* node with valid routing info */
317
318/*
319 * priority levels (or metrics)
320 *
321 */
322
323
324struct fib6_table {
325 struct hlist_node tb6_hlist;
326 u32 tb6_id;
327 spinlock_t tb6_lock;
328 struct fib6_node tb6_root;
329 struct inet_peer_base tb6_peers;
330 unsigned int flags;
331 unsigned int fib_seq;
332#define RT6_TABLE_HAS_DFLT_ROUTER BIT(0)
333};
334
335#define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
336#define RT6_TABLE_MAIN RT_TABLE_MAIN
337#define RT6_TABLE_DFLT RT6_TABLE_MAIN
338#define RT6_TABLE_INFO RT6_TABLE_MAIN
339#define RT6_TABLE_PREFIX RT6_TABLE_MAIN
340
341#ifdef CONFIG_IPV6_MULTIPLE_TABLES
342#define FIB6_TABLE_MIN 1
343#define FIB6_TABLE_MAX RT_TABLE_MAX
344#define RT6_TABLE_LOCAL RT_TABLE_LOCAL
345#else
346#define FIB6_TABLE_MIN RT_TABLE_MAIN
347#define FIB6_TABLE_MAX FIB6_TABLE_MIN
348#define RT6_TABLE_LOCAL RT6_TABLE_MAIN
349#endif
350
351typedef struct rt6_info *(*pol_lookup_t)(struct net *,
352 struct fib6_table *,
353 struct flowi6 *,
354 const struct sk_buff *, int);
355
356struct fib6_entry_notifier_info {
357 struct fib_notifier_info info; /* must be first */
358 struct rt6_info *rt;
359};
360
361/*
362 * exported functions
363 */
364
365struct fib6_table *fib6_get_table(struct net *net, u32 id);
366struct fib6_table *fib6_new_table(struct net *net, u32 id);
367struct dst_entry *fib6_rule_lookup(struct net *net, struct flowi6 *fl6,
368 const struct sk_buff *skb,
369 int flags, pol_lookup_t lookup);
370
371struct fib6_node *fib6_lookup(struct fib6_node *root,
372 const struct in6_addr *daddr,
373 const struct in6_addr *saddr);
374
375struct fib6_node *fib6_locate(struct fib6_node *root,
376 const struct in6_addr *daddr, int dst_len,
377 const struct in6_addr *saddr, int src_len,
378 bool exact_match);
379
380void fib6_clean_all(struct net *net, int (*func)(struct rt6_info *, void *arg),
381 void *arg);
382
383int fib6_add(struct fib6_node *root, struct rt6_info *rt,
384 struct nl_info *info, struct mx6_config *mxc,
385 struct netlink_ext_ack *extack);
386int fib6_del(struct rt6_info *rt, struct nl_info *info);
387
388void inet6_rt_notify(int event, struct rt6_info *rt, struct nl_info *info,
389 unsigned int flags);
390
391void fib6_run_gc(unsigned long expires, struct net *net, bool force);
392
393void fib6_gc_cleanup(void);
394
395int fib6_init(void);
396
397int ipv6_route_open(struct inode *inode, struct file *file);
398
399int call_fib6_notifier(struct notifier_block *nb, struct net *net,
400 enum fib_event_type event_type,
401 struct fib_notifier_info *info);
402int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
403 struct fib_notifier_info *info);
404
405int __net_init fib6_notifier_init(struct net *net);
406void __net_exit fib6_notifier_exit(struct net *net);
407
408unsigned int fib6_tables_seq_read(struct net *net);
409int fib6_tables_dump(struct net *net, struct notifier_block *nb);
410
411void fib6_update_sernum(struct rt6_info *rt);
412void fib6_update_sernum_upto_root(struct net *net, struct rt6_info *rt);
413
414#ifdef CONFIG_IPV6_MULTIPLE_TABLES
415int fib6_rules_init(void);
416void fib6_rules_cleanup(void);
417bool fib6_rule_default(const struct fib_rule *rule);
418int fib6_rules_dump(struct net *net, struct notifier_block *nb);
419unsigned int fib6_rules_seq_read(struct net *net);
420
421static inline bool fib6_rules_early_flow_dissect(struct net *net,
422 struct sk_buff *skb,
423 struct flowi6 *fl6,
424 struct flow_keys *flkeys)
425{
426 unsigned int flag = FLOW_DISSECTOR_F_STOP_AT_ENCAP;
427
428 if (!net->ipv6.fib6_rules_require_fldissect)
429 return false;
430
431 skb_flow_dissect_flow_keys(skb, flkeys, flag);
432 fl6->fl6_sport = flkeys->ports.src;
433 fl6->fl6_dport = flkeys->ports.dst;
434 fl6->flowi6_proto = flkeys->basic.ip_proto;
435
436 return true;
437}
438#else
439static inline int fib6_rules_init(void)
440{
441 return 0;
442}
443static inline void fib6_rules_cleanup(void)
444{
445 return ;
446}
447static inline bool fib6_rule_default(const struct fib_rule *rule)
448{
449 return true;
450}
451static inline int fib6_rules_dump(struct net *net, struct notifier_block *nb)
452{
453 return 0;
454}
455static inline unsigned int fib6_rules_seq_read(struct net *net)
456{
457 return 0;
458}
459static inline bool fib6_rules_early_flow_dissect(struct net *net,
460 struct sk_buff *skb,
461 struct flowi6 *fl6,
462 struct flow_keys *flkeys)
463{
464 return false;
465}
466#endif
467#endif
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
30struct rt6_info;
31
32struct 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
41 struct in6_addr fc_dst;
42 struct in6_addr fc_src;
43 struct in6_addr fc_prefsrc;
44 struct in6_addr fc_gateway;
45
46 unsigned long fc_expires;
47 struct nlattr *fc_mx;
48 int fc_mx_len;
49
50 struct nl_info fc_nlinfo;
51};
52
53struct fib6_node {
54 struct fib6_node *parent;
55 struct fib6_node *left;
56 struct fib6_node *right;
57#ifdef CONFIG_IPV6_SUBTREES
58 struct fib6_node *subtree;
59#endif
60 struct rt6_info *leaf;
61
62 __u16 fn_bit; /* bit key */
63 __u16 fn_flags;
64 __u32 fn_sernum;
65 struct rt6_info *rr_ptr;
66};
67
68#ifndef CONFIG_IPV6_SUBTREES
69#define FIB6_SUBTREE(fn) NULL
70#else
71#define FIB6_SUBTREE(fn) ((fn)->subtree)
72#endif
73
74/*
75 * routing information
76 *
77 */
78
79struct rt6key {
80 struct in6_addr addr;
81 int plen;
82};
83
84struct fib6_table;
85
86struct rt6_info {
87 struct dst_entry dst;
88
89 /*
90 * Tail elements of dst_entry (__refcnt etc.)
91 * and these elements (rarely used in hot path) are in
92 * the same cache line.
93 */
94 struct fib6_table *rt6i_table;
95 struct fib6_node *rt6i_node;
96
97 struct in6_addr rt6i_gateway;
98
99 atomic_t rt6i_ref;
100
101 /* These are in a separate cache line. */
102 struct rt6key rt6i_dst ____cacheline_aligned_in_smp;
103 u32 rt6i_flags;
104 struct rt6key rt6i_src;
105 struct rt6key rt6i_prefsrc;
106 u32 rt6i_metric;
107 u32 rt6i_peer_genid;
108
109 struct inet6_dev *rt6i_idev;
110 struct inet_peer *rt6i_peer;
111
112#ifdef CONFIG_XFRM
113 u32 rt6i_flow_cache_genid;
114#endif
115 /* more non-fragment space at head required */
116 unsigned short rt6i_nfheader_len;
117
118 u8 rt6i_protocol;
119};
120
121static inline struct inet6_dev *ip6_dst_idev(struct dst_entry *dst)
122{
123 return ((struct rt6_info *)dst)->rt6i_idev;
124}
125
126static inline void rt6_clean_expires(struct rt6_info *rt)
127{
128 if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
129 dst_release(rt->dst.from);
130
131 rt->rt6i_flags &= ~RTF_EXPIRES;
132 rt->dst.from = NULL;
133}
134
135static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
136{
137 if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
138 dst_release(rt->dst.from);
139
140 rt->rt6i_flags |= RTF_EXPIRES;
141 rt->dst.expires = expires;
142}
143
144static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
145{
146 if (!(rt->rt6i_flags & RTF_EXPIRES)) {
147 if (rt->dst.from)
148 dst_release(rt->dst.from);
149 /* dst_set_expires relies on expires == 0
150 * if it has not been set previously.
151 */
152 rt->dst.expires = 0;
153 }
154
155 dst_set_expires(&rt->dst, timeout);
156 rt->rt6i_flags |= RTF_EXPIRES;
157}
158
159static inline void rt6_set_from(struct rt6_info *rt, struct rt6_info *from)
160{
161 struct dst_entry *new = (struct dst_entry *) from;
162
163 if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from) {
164 if (new == rt->dst.from)
165 return;
166 dst_release(rt->dst.from);
167 }
168
169 rt->rt6i_flags &= ~RTF_EXPIRES;
170 rt->dst.from = new;
171 dst_hold(new);
172}
173
174struct fib6_walker_t {
175 struct list_head lh;
176 struct fib6_node *root, *node;
177 struct rt6_info *leaf;
178 unsigned char state;
179 unsigned char prune;
180 unsigned int skip;
181 unsigned int count;
182 int (*func)(struct fib6_walker_t *);
183 void *args;
184};
185
186struct rt6_statistics {
187 __u32 fib_nodes;
188 __u32 fib_route_nodes;
189 __u32 fib_rt_alloc; /* permanent routes */
190 __u32 fib_rt_entries; /* rt entries in table */
191 __u32 fib_rt_cache; /* cache routes */
192 __u32 fib_discarded_routes;
193};
194
195#define RTN_TL_ROOT 0x0001
196#define RTN_ROOT 0x0002 /* tree root node */
197#define RTN_RTINFO 0x0004 /* node with valid routing info */
198
199/*
200 * priority levels (or metrics)
201 *
202 */
203
204
205struct fib6_table {
206 struct hlist_node tb6_hlist;
207 u32 tb6_id;
208 rwlock_t tb6_lock;
209 struct fib6_node tb6_root;
210};
211
212#define RT6_TABLE_UNSPEC RT_TABLE_UNSPEC
213#define RT6_TABLE_MAIN RT_TABLE_MAIN
214#define RT6_TABLE_DFLT RT6_TABLE_MAIN
215#define RT6_TABLE_INFO RT6_TABLE_MAIN
216#define RT6_TABLE_PREFIX RT6_TABLE_MAIN
217
218#ifdef CONFIG_IPV6_MULTIPLE_TABLES
219#define FIB6_TABLE_MIN 1
220#define FIB6_TABLE_MAX RT_TABLE_MAX
221#define RT6_TABLE_LOCAL RT_TABLE_LOCAL
222#else
223#define FIB6_TABLE_MIN RT_TABLE_MAIN
224#define FIB6_TABLE_MAX FIB6_TABLE_MIN
225#define RT6_TABLE_LOCAL RT6_TABLE_MAIN
226#endif
227
228typedef struct rt6_info *(*pol_lookup_t)(struct net *,
229 struct fib6_table *,
230 struct flowi6 *, int);
231
232/*
233 * exported functions
234 */
235
236extern struct fib6_table *fib6_get_table(struct net *net, u32 id);
237extern struct fib6_table *fib6_new_table(struct net *net, u32 id);
238extern struct dst_entry *fib6_rule_lookup(struct net *net,
239 struct flowi6 *fl6, int flags,
240 pol_lookup_t lookup);
241
242extern struct fib6_node *fib6_lookup(struct fib6_node *root,
243 const struct in6_addr *daddr,
244 const struct in6_addr *saddr);
245
246struct fib6_node *fib6_locate(struct fib6_node *root,
247 const struct in6_addr *daddr, int dst_len,
248 const struct in6_addr *saddr, int src_len);
249
250extern void fib6_clean_all_ro(struct net *net,
251 int (*func)(struct rt6_info *, void *arg),
252 int prune, void *arg);
253
254extern void fib6_clean_all(struct net *net,
255 int (*func)(struct rt6_info *, void *arg),
256 int prune, void *arg);
257
258extern int fib6_add(struct fib6_node *root,
259 struct rt6_info *rt,
260 struct nl_info *info);
261
262extern int fib6_del(struct rt6_info *rt,
263 struct nl_info *info);
264
265extern void inet6_rt_notify(int event, struct rt6_info *rt,
266 struct nl_info *info);
267
268extern void fib6_run_gc(unsigned long expires,
269 struct net *net);
270
271extern void fib6_gc_cleanup(void);
272
273extern int fib6_init(void);
274
275#ifdef CONFIG_IPV6_MULTIPLE_TABLES
276extern int fib6_rules_init(void);
277extern void fib6_rules_cleanup(void);
278#else
279static inline int fib6_rules_init(void)
280{
281 return 0;
282}
283static inline void fib6_rules_cleanup(void)
284{
285 return ;
286}
287#endif
288#endif