xref: /freebsd/sys/net/route/route_var.h (revision d65cd7a57bf0600b722afc770838a5d0c1c3a8e1)
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/epoch.h>
39 #include <netinet/in.h>		/* struct sockaddr_in */
40 #include <sys/counter.h>
41 
42 struct nh_control;
43 typedef int rnh_preadd_entry_f_t(u_int fibnum, const struct sockaddr *addr,
44 	const struct sockaddr *mask, struct nhop_object *nh);
45 
46 struct rib_head {
47 	struct radix_head	head;
48 	rn_matchaddr_f_t	*rnh_matchaddr;	/* longest match for sockaddr */
49 	rn_addaddr_f_t		*rnh_addaddr;	/* add based on sockaddr*/
50 	rn_deladdr_f_t		*rnh_deladdr;	/* remove based on sockaddr */
51 	rn_lookup_f_t		*rnh_lookup;	/* exact match for sockaddr */
52 	rn_walktree_t		*rnh_walktree;	/* traverse tree */
53 	rn_walktree_from_t	*rnh_walktree_from; /* traverse tree below a */
54 	rnh_preadd_entry_f_t	*rnh_preadd;	/* hook to alter record prior to insertion */
55 	rt_gen_t		rnh_gen;	/* generation counter */
56 	int			rnh_multipath;	/* multipath capable ? */
57 	struct radix_node	rnh_nodes[3];	/* empty tree for common case */
58 	struct rmlock		rib_lock;	/* config/data path lock */
59 	struct radix_mask_head	rmhead;		/* masks radix head */
60 	struct vnet		*rib_vnet;	/* vnet pointer */
61 	int			rib_family;	/* AF of the rtable */
62 	u_int			rib_fibnum;	/* fib number */
63 	struct callout		expire_callout;	/* Callout for expiring dynamic routes */
64 	time_t			next_expire;	/* Next expire run ts */
65 	struct nh_control	*nh_control;	/* nexthop subsystem data */
66 };
67 
68 #define	RIB_RLOCK_TRACKER	struct rm_priotracker _rib_tracker
69 #define	RIB_LOCK_INIT(rh)	rm_init(&(rh)->rib_lock, "rib head lock")
70 #define	RIB_LOCK_DESTROY(rh)	rm_destroy(&(rh)->rib_lock)
71 #define	RIB_RLOCK(rh)		rm_rlock(&(rh)->rib_lock, &_rib_tracker)
72 #define	RIB_RUNLOCK(rh)		rm_runlock(&(rh)->rib_lock, &_rib_tracker)
73 #define	RIB_WLOCK(rh)		rm_wlock(&(rh)->rib_lock)
74 #define	RIB_WUNLOCK(rh)		rm_wunlock(&(rh)->rib_lock)
75 #define	RIB_LOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_LOCKED)
76 #define	RIB_WLOCK_ASSERT(rh)	rm_assert(&(rh)->rib_lock, RA_WLOCKED)
77 
78 /* Constants */
79 #define	RIB_MAX_RETRIES	3
80 
81 /* Macro for verifying fields in af-specific 'struct route' structures */
82 #define CHK_STRUCT_FIELD_GENERIC(_s1, _f1, _s2, _f2)			\
83 _Static_assert(sizeof(((_s1 *)0)->_f1) == sizeof(((_s2 *)0)->_f2),	\
84 		"Fields " #_f1 " and " #_f2 " size differs");		\
85 _Static_assert(__offsetof(_s1, _f1) == __offsetof(_s2, _f2),		\
86 		"Fields " #_f1 " and " #_f2 " offset differs");
87 
88 #define _CHK_ROUTE_FIELD(_route_new, _field) \
89 	CHK_STRUCT_FIELD_GENERIC(struct route, _field, _route_new, _field)
90 
91 #define CHK_STRUCT_ROUTE_FIELDS(_route_new)	\
92 	_CHK_ROUTE_FIELD(_route_new, ro_nh)	\
93 	_CHK_ROUTE_FIELD(_route_new, ro_lle)	\
94 	_CHK_ROUTE_FIELD(_route_new, ro_prepend)\
95 	_CHK_ROUTE_FIELD(_route_new, ro_plen)	\
96 	_CHK_ROUTE_FIELD(_route_new, ro_flags)	\
97 	_CHK_ROUTE_FIELD(_route_new, ro_mtu)	\
98 	_CHK_ROUTE_FIELD(_route_new, spare)
99 
100 #define CHK_STRUCT_ROUTE_COMPAT(_ro_new, _dst_new)				\
101 CHK_STRUCT_ROUTE_FIELDS(_ro_new);						\
102 _Static_assert(__offsetof(struct route, ro_dst) == __offsetof(_ro_new, _dst_new),\
103 		"ro_dst and " #_dst_new " are at different offset")
104 
105 struct rib_head *rt_tables_get_rnh(int fib, int family);
106 void rt_mpath_init_rnh(struct rib_head *rnh);
107 
108 VNET_PCPUSTAT_DECLARE(struct rtstat, rtstat);
109 #define	RTSTAT_ADD(name, val)	\
110 	VNET_PCPUSTAT_ADD(struct rtstat, rtstat, name, (val))
111 #define	RTSTAT_INC(name)	RTSTAT_ADD(name, 1)
112 
113 struct rtentry {
114 	struct	radix_node rt_nodes[2];	/* tree glue, and other values */
115 	/*
116 	 * XXX struct rtentry must begin with a struct radix_node (or two!)
117 	 * because the code does some casts of a 'struct radix_node *'
118 	 * to a 'struct rtentry *'
119 	 */
120 #define	rt_key(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_key)))
121 #define	rt_mask(r)	(*((struct sockaddr **)(&(r)->rt_nodes->rn_mask)))
122 #define	rt_key_const(r)		(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_key)))
123 #define	rt_mask_const(r)	(*((const struct sockaddr * const *)(&(r)->rt_nodes->rn_mask)))
124 
125 	/*
126 	 * 2 radix_node structurs above consists of 2x6 pointers, leaving
127 	 * 4 pointers (32 bytes) of the second cache line on amd64.
128 	 *
129 	 */
130 	struct nhop_object	*rt_nhop;	/* nexthop data */
131 	union {
132 		/*
133 		 * Destination address storage.
134 		 * sizeof(struct sockaddr_in6) == 28, however
135 		 * the dataplane-relevant part (e.g. address) lies
136 		 * at offset 8..24, making the address not crossing
137 		 * cacheline boundary.
138 		 */
139 		struct sockaddr_in	rt_dst4;
140 		struct sockaddr_in6	rt_dst6;
141 		struct sockaddr		rt_dst;
142 		char			rt_dstb[28];
143 	};
144 
145 	int		rt_flags;	/* up/down?, host/net */
146 	int		rt_refcnt;	/* # held references */
147 	u_long		rt_weight;	/* absolute weight */
148 	u_long		rt_expire;	/* lifetime for route, e.g. redirect */
149 #define	rt_endzero	rt_mtx
150 	struct mtx	rt_mtx;		/* mutex for routing entry */
151 	struct rtentry	*rt_chain;	/* pointer to next rtentry to delete */
152 	struct epoch_context	rt_epoch_ctx;	/* net epoch tracker */
153 };
154 
155 #define	RT_LOCK_INIT(_rt) \
156 	mtx_init(&(_rt)->rt_mtx, "rtentry", NULL, MTX_DEF | MTX_DUPOK | MTX_NEW)
157 #define	RT_LOCK(_rt)		mtx_lock(&(_rt)->rt_mtx)
158 #define	RT_UNLOCK(_rt)		mtx_unlock(&(_rt)->rt_mtx)
159 #define	RT_LOCK_DESTROY(_rt)	mtx_destroy(&(_rt)->rt_mtx)
160 #define	RT_LOCK_ASSERT(_rt)	mtx_assert(&(_rt)->rt_mtx, MA_OWNED)
161 #define	RT_UNLOCK_COND(_rt)	do {				\
162 	if (mtx_owned(&(_rt)->rt_mtx))				\
163 		mtx_unlock(&(_rt)->rt_mtx);			\
164 } while (0)
165 
166 #define	RT_ADDREF(_rt)	do {					\
167 	RT_LOCK_ASSERT(_rt);					\
168 	KASSERT((_rt)->rt_refcnt >= 0,				\
169 		("negative refcnt %d", (_rt)->rt_refcnt));	\
170 	(_rt)->rt_refcnt++;					\
171 } while (0)
172 
173 #define	RT_REMREF(_rt)	do {					\
174 	RT_LOCK_ASSERT(_rt);					\
175 	KASSERT((_rt)->rt_refcnt > 0,				\
176 		("bogus refcnt %d", (_rt)->rt_refcnt));	\
177 	(_rt)->rt_refcnt--;					\
178 } while (0)
179 
180 #define	RTFREE_LOCKED(_rt) do {					\
181 	if ((_rt)->rt_refcnt <= 1)				\
182 		rtfree(_rt);					\
183 	else {							\
184 		RT_REMREF(_rt);					\
185 		RT_UNLOCK(_rt);					\
186 	}							\
187 	/* guard against invalid refs */			\
188 	_rt = 0;						\
189 } while (0)
190 
191 #define	RTFREE(_rt) do {					\
192 	RT_LOCK(_rt);						\
193 	RTFREE_LOCKED(_rt);					\
194 } while (0)
195 
196 /*
197  * With the split between the routing entry and the nexthop,
198  *  rt_flags has to be split between these 2 entries. As rtentry
199  *  mostly contains prefix data and is thought to be generic enough
200  *  so one can transparently change the nexthop pointer w/o requiring
201  *  any other rtentry changes, most of rt_flags shifts to the particular nexthop.
202  * /
203  *
204  * RTF_UP: rtentry, as an indication that it is linked.
205  * RTF_HOST: rtentry, nhop. The latter indication is needed for the datapath
206  * RTF_DYNAMIC: nhop, to make rtentry generic.
207  * RTF_MODIFIED: nhop, to make rtentry generic. (legacy)
208  * -- "native" path (nhop) properties:
209  * RTF_GATEWAY, RTF_STATIC, RTF_PROTO1, RTF_PROTO2, RTF_PROTO3, RTF_FIXEDMTU,
210  *  RTF_PINNED, RTF_REJECT, RTF_BLACKHOLE, RTF_BROADCAST
211  */
212 
213 /* Nexthop rt flags mask */
214 #define	NHOP_RT_FLAG_MASK	(RTF_GATEWAY | RTF_HOST | RTF_REJECT | RTF_DYNAMIC | \
215     RTF_MODIFIED | RTF_STATIC | RTF_BLACKHOLE | RTF_PROTO1 | RTF_PROTO2 | \
216     RTF_PROTO3 | RTF_FIXEDMTU | RTF_PINNED | RTF_BROADCAST)
217 
218 /* rtentry rt flag mask */
219 #define	RTE_RT_FLAG_MASK	(RTF_UP | RTF_HOST)
220 
221 /* Nexthop selection */
222 #define	_NH2MP(_nh)	((struct nhgrp_object *)(_nh))
223 #define	_SELECT_NHOP(_nh, _flowid)	\
224 	(_NH2MP(_nh))->nhops[(_flowid) % (_NH2MP(_nh))->mp_size]
225 #define	_RT_SELECT_NHOP(_nh, _flowid)	\
226 	((!NH_IS_MULTIPATH(_nh)) ? (_nh) : _SELECT_NHOP(_nh, _flowid))
227 #define	RT_SELECT_NHOP(_rt, _flowid)	_RT_SELECT_NHOP((_rt)->rt_nhop, _flowid)
228 
229 /* rte<>nhop translation */
230 static inline uint16_t
231 fib_rte_to_nh_flags(int rt_flags)
232 {
233 	uint16_t res;
234 
235 	res = (rt_flags & RTF_REJECT) ? NHF_REJECT : 0;
236 	res |= (rt_flags & RTF_HOST) ? NHF_HOST : 0;
237 	res |= (rt_flags & RTF_BLACKHOLE) ? NHF_BLACKHOLE : 0;
238 	res |= (rt_flags & (RTF_DYNAMIC|RTF_MODIFIED)) ? NHF_REDIRECT : 0;
239 	res |= (rt_flags & RTF_BROADCAST) ? NHF_BROADCAST : 0;
240 	res |= (rt_flags & RTF_GATEWAY) ? NHF_GATEWAY : 0;
241 
242 	return (res);
243 }
244 
245 void tmproutes_update(struct rib_head *rnh, struct rtentry *rt);
246 void tmproutes_init(struct rib_head *rh);
247 void tmproutes_destroy(struct rib_head *rh);
248 
249 #endif
250