xref: /freebsd/sys/net/route/route_var.h (revision 4ac8f4067096a9d4a00e41cd53bd5c4fa295fd15)
1 /*-
2  * Copyright (c) 2015-2016
3  * 	Alexander V. Chernikov <melifaro@FreeBSD.org>
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _NET_ROUTE_VAR_H_
33 #define _NET_ROUTE_VAR_H_
34 
35 #ifndef RNF_NORMAL
36 #include <net/radix.h>
37 #endif
38 #include <sys/ck.h>
39 #include <sys/epoch.h>
40 #include <netinet/in.h>		/* struct sockaddr_in */
41 #include <sys/counter.h>
42 #include <net/route/nhop.h>
43 
44 struct nh_control;
45 /* Sets prefix-specific nexthop flags (NHF_DEFAULT, RTF/NHF_HOST, RTF_BROADCAST,..) */
46 typedef int rnh_set_nh_pfxflags_f_t(u_int fibnum, const struct sockaddr *addr,
47 	const struct sockaddr *mask, struct nhop_object *nh);
48 /* Fills in family-specific details that are not yet set up (mtu, nhop type, ..) */
49 typedef int rnh_augment_nh_f_t(u_int fibnum, struct nhop_object *nh);
50 
51 struct rib_head {
52 	struct radix_head	head;
53 	rn_matchaddr_f_t	*rnh_matchaddr;	/* longest match for sockaddr */
54 	rn_addaddr_f_t		*rnh_addaddr;	/* add based on sockaddr*/
55 	rn_deladdr_f_t		*rnh_deladdr;	/* remove based on sockaddr */
56 	rn_lookup_f_t		*rnh_lookup;	/* exact match for sockaddr */
57 	rn_walktree_t		*rnh_walktree;	/* traverse tree */
58 	rn_walktree_from_t	*rnh_walktree_from; /* traverse tree below a */
59 	rnh_set_nh_pfxflags_f_t	*rnh_set_nh_pfxflags;	/* hook to alter record prior to insertion */
60 	rt_gen_t		rnh_gen;	/* datapath generation counter */
61 	int			rnh_multipath;	/* multipath capable ? */
62 	struct radix_node	rnh_nodes[3];	/* empty tree for common case */
63 	struct rmlock		rib_lock;	/* config/data path lock */
64 	struct radix_mask_head	rmhead;		/* masks radix head */
65 	struct vnet		*rib_vnet;	/* vnet pointer */
66 	int			rib_family;	/* AF of the rtable */
67 	u_int			rib_fibnum;	/* fib number */
68 	struct callout		expire_callout;	/* Callout for expiring dynamic routes */
69 	time_t			next_expire;	/* Next expire run ts */
70 	uint32_t		rnh_prefixes;	/* Number of prefixes */
71 	rt_gen_t		rnh_gen_rib;	/* fib algo: rib generation counter */
72 	uint32_t		rib_dying:1;	/* rib is detaching */
73 	uint32_t		rib_algo_fixed:1;/* fixed algorithm */
74 	uint32_t		rib_algo_init:1;/* algo init done */
75 	struct nh_control	*nh_control;	/* nexthop subsystem data */
76 	rnh_augment_nh_f_t	*rnh_augment_nh;/* hook to alter nexthop prior to insertion */
77 	CK_STAILQ_HEAD(, rib_subscription)	rnh_subscribers;/* notification subscribers */
78 };
79 
80 #define	RIB_RLOCK_TRACKER	struct rm_priotracker _rib_tracker
81 #define	RIB_LOCK_INIT(rh)	rm_init_flags(&(rh)->rib_lock, "rib head lock", RM_DUPOK)
82 #define	RIB_LOCK_DESTROY(rh)	rm_destroy(&(rh)->rib_lock)
83 #define	RIB_RLOCK(rh)		rm_rlock(&(rh)->rib_lock, &_rib_tracker)
84 #define	RIB_RUNLOCK(rh)		rm_runlock(&(rh)->rib_lock, &_rib_tracker)
85 #define	RIB_WLOCK(rh)		rm_wlock(&(rh)->rib_lock)
86 #define	RIB_WUNLOCK(rh)		rm_wunlock(&(rh)->rib_lock)
87 #define	RIB_LOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_LOCKED)
88 #define	RIB_WLOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_WLOCKED)
89 
90 /* Constants */
91 #define	RIB_MAX_RETRIES	3
92 #define	RT_MAXFIBS	UINT16_MAX
93 #define	RIB_MAX_MPATH_WIDTH	64
94 
95 /* Macro for verifying fields in af-specific 'struct route' structures */
96 #define CHK_STRUCT_FIELD_GENERIC(_s1, _f1, _s2, _f2)			\
97 _Static_assert(sizeof(((_s1 *)0)->_f1) == sizeof(((_s2 *)0)->_f2),	\
98 		"Fields " #_f1 " and " #_f2 " size differs");		\
99 _Static_assert(__offsetof(_s1, _f1) == __offsetof(_s2, _f2),		\
100 		"Fields " #_f1 " and " #_f2 " offset differs");
101 
102 #define _CHK_ROUTE_FIELD(_route_new, _field) \
103 	CHK_STRUCT_FIELD_GENERIC(struct route, _field, _route_new, _field)
104 
105 #define CHK_STRUCT_ROUTE_FIELDS(_route_new)	\
106 	_CHK_ROUTE_FIELD(_route_new, ro_nh)	\
107 	_CHK_ROUTE_FIELD(_route_new, ro_lle)	\
108 	_CHK_ROUTE_FIELD(_route_new, ro_prepend)\
109 	_CHK_ROUTE_FIELD(_route_new, ro_plen)	\
110 	_CHK_ROUTE_FIELD(_route_new, ro_flags)	\
111 	_CHK_ROUTE_FIELD(_route_new, ro_mtu)	\
112 	_CHK_ROUTE_FIELD(_route_new, spare)
113 
114 #define CHK_STRUCT_ROUTE_COMPAT(_ro_new, _dst_new)				\
115 CHK_STRUCT_ROUTE_FIELDS(_ro_new);						\
116 _Static_assert(__offsetof(struct route, ro_dst) == __offsetof(_ro_new, _dst_new),\
117 		"ro_dst and " #_dst_new " are at different offset")
118 
119 static inline void
120 rib_bump_gen(struct rib_head *rnh)
121 {
122 #ifdef FIB_ALGO
123 	rnh->rnh_gen_rib++;
124 #else
125 	rnh->rnh_gen++;
126 #endif
127 }
128 
129 struct rib_head *rt_tables_get_rnh(uint32_t table, sa_family_t family);
130 int rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum);
131 struct rib_cmd_info;
132 
133 VNET_PCPUSTAT_DECLARE(struct rtstat, rtstat);
134 #define	RTSTAT_ADD(name, val)	\
135 	VNET_PCPUSTAT_ADD(struct rtstat, rtstat, name, (val))
136 #define	RTSTAT_INC(name)	RTSTAT_ADD(name, 1)
137 
138 /*
139  * Convert a 'struct radix_node *' to a 'struct rtentry *'.
140  * The operation can be done safely (in this code) because a
141  * 'struct rtentry' starts with two 'struct radix_node''s, the first
142  * one representing leaf nodes in the routing tree, which is
143  * what the code in radix.c passes us as a 'struct radix_node'.
144  *
145  * But because there are a lot of assumptions in this conversion,
146  * do not cast explicitly, but always use the macro below.
147  */
148 #define RNTORT(p)	((struct rtentry *)(p))
149 
150 struct rtentry {
151 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
152 	/*
153 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
154 	 * because the code does some casts of a 'struct radix_node *'
155 	 * to a 'struct rtentry *'
156 	 */
157 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
158 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
159 #define	rt_key_const(r)		(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_key)))
160 #define	rt_mask_const(r)	(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_mask)))
161 
162 	/*
163 	 * 2 radix_node structurs above consists of 2x6 pointers, leaving
164 	 * 4 pointers (32 bytes) of the second cache line on amd64.
165 	 *
166 	 */
167 	struct nhop_object	*rt_nhop;	/* nexthop data */
168 	union {
169 		/*
170 		 * Destination address storage.
171 		 * sizeof(struct sockaddr_in6) == 28, however
172 		 * the dataplane-relevant part (e.g. address) lies
173 		 * at offset 8..24, making the address not crossing
174 		 * cacheline boundary.
175 		 */
176 		struct sockaddr_in	rt_dst4;
177 		struct sockaddr_in6	rt_dst6;
178 		struct sockaddr		rt_dst;
179 		char			rt_dstb[28];
180 	};
181 
182 	int		rte_flags;	/* up/down?, host/net */
183 	u_long		rt_weight;	/* absolute weight */
184 	struct rtentry	*rt_chain;	/* pointer to next rtentry to delete */
185 	struct epoch_context	rt_epoch_ctx;	/* net epoch tracker */
186 };
187 
188 /*
189  * With the split between the routing entry and the nexthop,
190  *  rt_flags has to be split between these 2 entries. As rtentry
191  *  mostly contains prefix data and is thought to be generic enough
192  *  so one can transparently change the nexthop pointer w/o requiring
193  *  any other rtentry changes, most of rt_flags shifts to the particular nexthop.
194  * /
195  *
196  * RTF_UP: rtentry, as an indication that it is linked.
197  * RTF_HOST: rtentry, nhop. The latter indication is needed for the datapath
198  * RTF_DYNAMIC: nhop, to make rtentry generic.
199  * RTF_MODIFIED: nhop, to make rtentry generic. (legacy)
200  * -- "native" path (nhop) properties:
201  * RTF_GATEWAY, RTF_STATIC, RTF_PROTO1, RTF_PROTO2, RTF_PROTO3, RTF_FIXEDMTU,
202  *  RTF_PINNED, RTF_REJECT, RTF_BLACKHOLE, RTF_BROADCAST
203  */
204 
205 /* rtentry rt flag mask */
206 #define	RTE_RT_FLAG_MASK	(RTF_UP | RTF_HOST)
207 
208 /* route_temporal.c */
209 void tmproutes_update(struct rib_head *rnh, struct rtentry *rt, struct nhop_object *nh);
210 void tmproutes_init(struct rib_head *rh);
211 void tmproutes_destroy(struct rib_head *rh);
212 
213 /* route_ctl.c */
214 struct route_nhop_data;
215 int change_route(struct rib_head *rnh, struct rtentry *rt,
216     struct route_nhop_data *rnd, struct rib_cmd_info *rc);
217 int change_route_conditional(struct rib_head *rnh, struct rtentry *rt,
218     struct route_nhop_data *nhd_orig, struct route_nhop_data *nhd_new,
219     struct rib_cmd_info *rc);
220 struct rtentry *lookup_prefix(struct rib_head *rnh,
221     const struct rt_addrinfo *info, struct route_nhop_data *rnd);
222 struct rtentry *lookup_prefix_rt(struct rib_head *rnh, const struct rtentry *rt,
223     struct route_nhop_data *rnd);
224 int rib_copy_route(struct rtentry *rt, const struct route_nhop_data *rnd_src,
225     struct rib_head *rh_dst, struct rib_cmd_info *rc);
226 
227 bool nhop_can_multipath(const struct nhop_object *nh);
228 bool match_nhop_gw(const struct nhop_object *nh, const struct sockaddr *gw);
229 int check_info_match_nhop(const struct rt_addrinfo *info,
230     const struct rtentry *rt, const struct nhop_object *nh);
231 bool rib_can_4o6_nhop(void);
232 
233 /* route_rtentry.c */
234 void vnet_rtzone_init(void);
235 void vnet_rtzone_destroy(void);
236 void rt_free(struct rtentry *rt);
237 void rt_free_immediate(struct rtentry *rt);
238 struct rtentry *rt_alloc(struct rib_head *rnh, const struct sockaddr *dst,
239     struct sockaddr *netmask);
240 
241 /* subscriptions */
242 void rib_init_subscriptions(struct rib_head *rnh);
243 void rib_destroy_subscriptions(struct rib_head *rnh);
244 
245 /* route_ifaddrs.c */
246 void rib_copy_kernel_routes(struct rib_head *rh_src, struct rib_head *rh_dst);
247 
248 /* Nexhops */
249 void nhops_init(void);
250 int nhops_init_rib(struct rib_head *rh);
251 void nhops_destroy_rib(struct rib_head *rh);
252 void nhop_ref_object(struct nhop_object *nh);
253 int nhop_try_ref_object(struct nhop_object *nh);
254 void nhop_ref_any(struct nhop_object *nh);
255 void nhop_free_any(struct nhop_object *nh);
256 struct nhop_object *nhop_get_nhop_internal(struct rib_head *rnh,
257     struct nhop_object *nh, int *perror);
258 
259 bool nhop_check_gateway(int upper_family, int neigh_family);
260 
261 int nhop_create_from_info(struct rib_head *rnh, struct rt_addrinfo *info,
262     struct nhop_object **nh_ret);
263 int nhop_create_from_nhop(struct rib_head *rnh, const struct nhop_object *nh_orig,
264     struct rt_addrinfo *info, struct nhop_object **pnh_priv);
265 
266 void nhops_update_ifmtu(struct rib_head *rh, struct ifnet *ifp, uint32_t mtu);
267 int nhops_dump_sysctl(struct rib_head *rh, struct sysctl_req *w);
268 
269 /* MULTIPATH */
270 #define	MPF_MULTIPATH	0x08	/* need to be consistent with NHF_MULTIPATH */
271 
272 struct nhgrp_object {
273 	uint16_t		nhg_flags;	/* nexthop group flags */
274 	uint8_t			nhg_size;	/* dataplain group size */
275 	uint8_t			spare;
276 	struct nhop_object	*nhops[0];	/* nhops */
277 };
278 
279 static inline struct nhop_object *
280 nhop_select(struct nhop_object *nh, uint32_t flowid)
281 {
282 
283 #ifdef ROUTE_MPATH
284 	if (NH_IS_NHGRP(nh)) {
285 		struct nhgrp_object *nhg = (struct nhgrp_object *)nh;
286 		nh = nhg->nhops[flowid % nhg->nhg_size];
287 	}
288 #endif
289 	return (nh);
290 }
291 
292 
293 struct weightened_nhop;
294 
295 /* mpath_ctl.c */
296 int add_route_mpath(struct rib_head *rnh, struct rt_addrinfo *info,
297     struct rtentry *rt, struct route_nhop_data *rnd_add,
298     struct route_nhop_data *rnd_orig, struct rib_cmd_info *rc);
299 
300 /* nhgrp.c */
301 int nhgrp_ctl_init(struct nh_control *ctl);
302 void nhgrp_ctl_free(struct nh_control *ctl);
303 void nhgrp_ctl_unlink_all(struct nh_control *ctl);
304 
305 
306 /* nhgrp_ctl.c */
307 int nhgrp_dump_sysctl(struct rib_head *rh, struct sysctl_req *w);
308 
309 int nhgrp_get_filtered_group(struct rib_head *rh, const struct rtentry *rt,
310     const struct nhgrp_object *src, rib_filter_f_t flt_func, void *flt_data,
311     struct route_nhop_data *rnd);
312 int nhgrp_get_addition_group(struct rib_head *rnh,
313     struct route_nhop_data *rnd_orig, struct route_nhop_data *rnd_add,
314     struct route_nhop_data *rnd_new);
315 
316 void nhgrp_ref_object(struct nhgrp_object *nhg);
317 uint32_t nhgrp_get_idx(const struct nhgrp_object *nhg);
318 void nhgrp_free(struct nhgrp_object *nhg);
319 
320 /* rtsock */
321 int rtsock_routemsg(int cmd, struct rtentry *rt, struct nhop_object *nh,
322     int fibnum);
323 int rtsock_routemsg_info(int cmd, struct rt_addrinfo *info, int fibnum);
324 int rtsock_addrmsg(int cmd, struct ifaddr *ifa, int fibnum);
325 
326 
327 /* lookup_framework.c */
328 void fib_grow_rtables(uint32_t new_num_tables);
329 void fib_setup_family(int family, uint32_t num_tables);
330 void fib_destroy_rib(struct rib_head *rh);
331 void vnet_fib_init(void);
332 void vnet_fib_destroy(void);
333 
334 /* Entropy data used for outbound hashing */
335 #define MPATH_ENTROPY_KEY_LEN	40
336 extern uint8_t mpath_entropy_key[MPATH_ENTROPY_KEY_LEN];
337 
338 #endif
339