xref: /freebsd/sys/net/route/route_var.h (revision 3cbb4cc200f8a0ad7ed08233425ea54524a21f1c)
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 #ifdef	RTDEBUG
45 #define	DPRINTF(_fmt, ...)	printf("%s: " _fmt "\n", __func__ , ## __VA_ARGS__)
46 #else
47 #define	DPRINTF(_fmt, ...)
48 #endif
49 
50 struct nh_control;
51 typedef int rnh_preadd_entry_f_t(u_int fibnum, const struct sockaddr *addr,
52 	const struct sockaddr *mask, struct nhop_object *nh);
53 
54 struct rib_head {
55 	struct radix_head	head;
56 	rn_matchaddr_f_t	*rnh_matchaddr;	/* longest match for sockaddr */
57 	rn_addaddr_f_t		*rnh_addaddr;	/* add based on sockaddr*/
58 	rn_deladdr_f_t		*rnh_deladdr;	/* remove based on sockaddr */
59 	rn_lookup_f_t		*rnh_lookup;	/* exact match for sockaddr */
60 	rn_walktree_t		*rnh_walktree;	/* traverse tree */
61 	rn_walktree_from_t	*rnh_walktree_from; /* traverse tree below a */
62 	rnh_preadd_entry_f_t	*rnh_preadd;	/* hook to alter record prior to insertion */
63 	rt_gen_t		rnh_gen;	/* generation counter */
64 	int			rnh_multipath;	/* multipath capable ? */
65 	struct radix_node	rnh_nodes[3];	/* empty tree for common case */
66 	struct rmlock		rib_lock;	/* config/data path lock */
67 	struct radix_mask_head	rmhead;		/* masks radix head */
68 	struct vnet		*rib_vnet;	/* vnet pointer */
69 	int			rib_family;	/* AF of the rtable */
70 	u_int			rib_fibnum;	/* fib number */
71 	struct callout		expire_callout;	/* Callout for expiring dynamic routes */
72 	time_t			next_expire;	/* Next expire run ts */
73 	struct nh_control	*nh_control;	/* nexthop subsystem data */
74 	CK_STAILQ_HEAD(, rib_subscription)	rnh_subscribers;/* notification subscribers */
75 };
76 
77 #define	RIB_RLOCK_TRACKER	struct rm_priotracker _rib_tracker
78 #define	RIB_LOCK_INIT(rh)	rm_init(&(rh)->rib_lock, "rib head lock")
79 #define	RIB_LOCK_DESTROY(rh)	rm_destroy(&(rh)->rib_lock)
80 #define	RIB_RLOCK(rh)		rm_rlock(&(rh)->rib_lock, &_rib_tracker)
81 #define	RIB_RUNLOCK(rh)		rm_runlock(&(rh)->rib_lock, &_rib_tracker)
82 #define	RIB_WLOCK(rh)		rm_wlock(&(rh)->rib_lock)
83 #define	RIB_WUNLOCK(rh)		rm_wunlock(&(rh)->rib_lock)
84 #define	RIB_LOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_LOCKED)
85 #define	RIB_WLOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_WLOCKED)
86 
87 /* Constants */
88 #define	RIB_MAX_RETRIES	3
89 #define	RT_MAXFIBS	UINT16_MAX
90 #define	RIB_MAX_MPATH_WIDTH	64
91 
92 /* Macro for verifying fields in af-specific 'struct route' structures */
93 #define CHK_STRUCT_FIELD_GENERIC(_s1, _f1, _s2, _f2)			\
94 _Static_assert(sizeof(((_s1 *)0)->_f1) == sizeof(((_s2 *)0)->_f2),	\
95 		"Fields " #_f1 " and " #_f2 " size differs");		\
96 _Static_assert(__offsetof(_s1, _f1) == __offsetof(_s2, _f2),		\
97 		"Fields " #_f1 " and " #_f2 " offset differs");
98 
99 #define _CHK_ROUTE_FIELD(_route_new, _field) \
100 	CHK_STRUCT_FIELD_GENERIC(struct route, _field, _route_new, _field)
101 
102 #define CHK_STRUCT_ROUTE_FIELDS(_route_new)	\
103 	_CHK_ROUTE_FIELD(_route_new, ro_nh)	\
104 	_CHK_ROUTE_FIELD(_route_new, ro_lle)	\
105 	_CHK_ROUTE_FIELD(_route_new, ro_prepend)\
106 	_CHK_ROUTE_FIELD(_route_new, ro_plen)	\
107 	_CHK_ROUTE_FIELD(_route_new, ro_flags)	\
108 	_CHK_ROUTE_FIELD(_route_new, ro_mtu)	\
109 	_CHK_ROUTE_FIELD(_route_new, spare)
110 
111 #define CHK_STRUCT_ROUTE_COMPAT(_ro_new, _dst_new)				\
112 CHK_STRUCT_ROUTE_FIELDS(_ro_new);						\
113 _Static_assert(__offsetof(struct route, ro_dst) == __offsetof(_ro_new, _dst_new),\
114 		"ro_dst and " #_dst_new " are at different offset")
115 
116 struct rib_head *rt_tables_get_rnh(uint32_t table, sa_family_t family);
117 int rt_getifa_fib(struct rt_addrinfo *info, u_int fibnum);
118 struct rib_cmd_info;
119 
120 VNET_PCPUSTAT_DECLARE(struct rtstat, rtstat);
121 #define	RTSTAT_ADD(name, val)	\
122 	VNET_PCPUSTAT_ADD(struct rtstat, rtstat, name, (val))
123 #define	RTSTAT_INC(name)	RTSTAT_ADD(name, 1)
124 
125 /*
126  * Convert a 'struct radix_node *' to a 'struct rtentry *'.
127  * The operation can be done safely (in this code) because a
128  * 'struct rtentry' starts with two 'struct radix_node''s, the first
129  * one representing leaf nodes in the routing tree, which is
130  * what the code in radix.c passes us as a 'struct radix_node'.
131  *
132  * But because there are a lot of assumptions in this conversion,
133  * do not cast explicitly, but always use the macro below.
134  */
135 #define RNTORT(p)	((struct rtentry *)(p))
136 
137 struct rtentry {
138 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
139 	/*
140 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
141 	 * because the code does some casts of a 'struct radix_node *'
142 	 * to a 'struct rtentry *'
143 	 */
144 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
145 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
146 #define	rt_key_const(r)		(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_key)))
147 #define	rt_mask_const(r)	(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_mask)))
148 
149 	/*
150 	 * 2 radix_node structurs above consists of 2x6 pointers, leaving
151 	 * 4 pointers (32 bytes) of the second cache line on amd64.
152 	 *
153 	 */
154 	struct nhop_object	*rt_nhop;	/* nexthop data */
155 	union {
156 		/*
157 		 * Destination address storage.
158 		 * sizeof(struct sockaddr_in6) == 28, however
159 		 * the dataplane-relevant part (e.g. address) lies
160 		 * at offset 8..24, making the address not crossing
161 		 * cacheline boundary.
162 		 */
163 		struct sockaddr_in	rt_dst4;
164 		struct sockaddr_in6	rt_dst6;
165 		struct sockaddr		rt_dst;
166 		char			rt_dstb[28];
167 	};
168 
169 	int		rte_flags;	/* up/down?, host/net */
170 	u_long		rt_weight;	/* absolute weight */
171 	u_long		rt_expire;	/* lifetime for route, e.g. redirect */
172 	struct rtentry	*rt_chain;	/* pointer to next rtentry to delete */
173 	struct epoch_context	rt_epoch_ctx;	/* net epoch tracker */
174 };
175 
176 /*
177  * With the split between the routing entry and the nexthop,
178  *  rt_flags has to be split between these 2 entries. As rtentry
179  *  mostly contains prefix data and is thought to be generic enough
180  *  so one can transparently change the nexthop pointer w/o requiring
181  *  any other rtentry changes, most of rt_flags shifts to the particular nexthop.
182  * /
183  *
184  * RTF_UP: rtentry, as an indication that it is linked.
185  * RTF_HOST: rtentry, nhop. The latter indication is needed for the datapath
186  * RTF_DYNAMIC: nhop, to make rtentry generic.
187  * RTF_MODIFIED: nhop, to make rtentry generic. (legacy)
188  * -- "native" path (nhop) properties:
189  * RTF_GATEWAY, RTF_STATIC, RTF_PROTO1, RTF_PROTO2, RTF_PROTO3, RTF_FIXEDMTU,
190  *  RTF_PINNED, RTF_REJECT, RTF_BLACKHOLE, RTF_BROADCAST
191  */
192 
193 /* Nexthop rt flags mask */
194 #define	NHOP_RT_FLAG_MASK	(RTF_GATEWAY | RTF_HOST | RTF_REJECT | RTF_DYNAMIC | \
195     RTF_MODIFIED | RTF_STATIC | RTF_BLACKHOLE | RTF_PROTO1 | RTF_PROTO2 | \
196     RTF_PROTO3 | RTF_FIXEDMTU | RTF_PINNED | RTF_BROADCAST)
197 
198 /* rtentry rt flag mask */
199 #define	RTE_RT_FLAG_MASK	(RTF_UP | RTF_HOST)
200 
201 /* route_temporal.c */
202 void tmproutes_update(struct rib_head *rnh, struct rtentry *rt);
203 void tmproutes_init(struct rib_head *rh);
204 void tmproutes_destroy(struct rib_head *rh);
205 
206 /* route_ctl.c */
207 struct route_nhop_data {
208 	union {
209 		struct nhop_object *rnd_nhop;
210 		struct nhgrp_object *rnd_nhgrp;
211 	};
212 	uint32_t rnd_weight;
213 };
214 
215 int change_route_nhop(struct rib_head *rnh, struct rtentry *rt,
216     struct rt_addrinfo *info, struct route_nhop_data *rnd,
217     struct rib_cmd_info *rc);
218 int change_route_conditional(struct rib_head *rnh, struct rtentry *rt,
219     struct rt_addrinfo *info, struct route_nhop_data *nhd_orig,
220     struct route_nhop_data *nhd_new, struct rib_cmd_info *rc);
221 struct rtentry *lookup_prefix(struct rib_head *rnh,
222     const struct rt_addrinfo *info, struct route_nhop_data *rnd);
223 
224 bool nhop_can_multipath(const struct nhop_object *nh);
225 bool match_nhop_gw(const struct nhop_object *nh, const struct sockaddr *gw);
226 int check_info_match_nhop(const struct rt_addrinfo *info,
227     const struct rtentry *rt, const struct nhop_object *nh);
228 int can_override_nhop(const struct rt_addrinfo *info,
229     const struct nhop_object *nh);
230 
231 void vnet_rtzone_init(void);
232 void vnet_rtzone_destroy(void);
233 
234 /* subscriptions */
235 void rib_init_subscriptions(struct rib_head *rnh);
236 void rib_destroy_subscriptions(struct rib_head *rnh);
237 
238 /* Nexhops */
239 void nhops_init(void);
240 int nhops_init_rib(struct rib_head *rh);
241 void nhops_destroy_rib(struct rib_head *rh);
242 void nhop_ref_object(struct nhop_object *nh);
243 int nhop_try_ref_object(struct nhop_object *nh);
244 void nhop_free_any(struct nhop_object *nh);
245 
246 void nhop_set_type(struct nhop_object *nh, enum nhop_type nh_type);
247 void nhop_set_rtflags(struct nhop_object *nh, int rt_flags);
248 
249 int nhop_create_from_info(struct rib_head *rnh, struct rt_addrinfo *info,
250     struct nhop_object **nh_ret);
251 int nhop_create_from_nhop(struct rib_head *rnh, const struct nhop_object *nh_orig,
252     struct rt_addrinfo *info, struct nhop_object **pnh_priv);
253 
254 void nhops_update_ifmtu(struct rib_head *rh, struct ifnet *ifp, uint32_t mtu);
255 int nhops_dump_sysctl(struct rib_head *rh, struct sysctl_req *w);
256 
257 /* MULTIPATH */
258 #define	MPF_MULTIPATH	0x08	/* need to be consistent with NHF_MULTIPATH */
259 
260 struct nhgrp_object {
261 	uint16_t		nhg_flags;	/* nexthop group flags */
262 	uint8_t			nhg_size;	/* dataplain group size */
263 	uint8_t			spare;
264 	struct nhop_object	*nhops[0];	/* nhops */
265 };
266 
267 static inline struct nhop_object *
268 nhop_select(struct nhop_object *nh, uint32_t flowid)
269 {
270 
271 #ifdef ROUTE_MPATH
272 	if (NH_IS_NHGRP(nh)) {
273 		struct nhgrp_object *nhg = (struct nhgrp_object *)nh;
274 		nh = nhg->nhops[flowid % nhg->nhg_size];
275 	}
276 #endif
277 	return (nh);
278 }
279 
280 
281 struct weightened_nhop;
282 
283 /* mpath_ctl.c */
284 int add_route_mpath(struct rib_head *rnh, struct rt_addrinfo *info,
285     struct rtentry *rt, struct route_nhop_data *rnd_add,
286     struct route_nhop_data *rnd_orig, struct rib_cmd_info *rc);
287 int del_route_mpath(struct rib_head *rh, struct rt_addrinfo *info,
288     struct rtentry *rt, struct nhgrp_object *nhg, struct rib_cmd_info *rc);
289 
290 /* nhgrp.c */
291 int nhgrp_ctl_init(struct nh_control *ctl);
292 void nhgrp_ctl_free(struct nh_control *ctl);
293 void nhgrp_ctl_unlink_all(struct nh_control *ctl);
294 
295 
296 /* nhgrp_ctl.c */
297 int nhgrp_dump_sysctl(struct rib_head *rh, struct sysctl_req *w);
298 
299 int nhgrp_get_group(struct rib_head *rh, struct weightened_nhop *wn,
300     int num_nhops, struct route_nhop_data *rnd);
301 typedef bool nhgrp_filter_cb_t(const struct nhop_object *nh, void *data);
302 int nhgrp_get_filtered_group(struct rib_head *rh, const struct nhgrp_object *src,
303     nhgrp_filter_cb_t flt_func, void *flt_data, struct route_nhop_data *rnd);
304 int nhgrp_get_addition_group(struct rib_head *rnh,
305     struct route_nhop_data *rnd_orig, struct route_nhop_data *rnd_add,
306     struct route_nhop_data *rnd_new);
307 
308 void nhgrp_free(struct nhgrp_object *nhg);
309 
310 /* Entropy data used for outbound hashing */
311 #define MPATH_ENTROPY_KEY_LEN	40
312 extern uint8_t mpath_entropy_key[MPATH_ENTROPY_KEY_LEN];
313 
314 #endif
315