xref: /freebsd/sys/netlink/route/route.h (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2022 Alexander V. Chernikov <melifaro@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 /*
29  * Route-related (RTM_<NEW|DEL|GET>ROUTE) message header and attributes.
30  */
31 
32 #ifndef _NETLINK_ROUTE_ROUTE_H_
33 #define _NETLINK_ROUTE_ROUTE_H_
34 
35 /* Base header for all of the relevant messages */
36 struct rtmsg {
37 	unsigned char	rtm_family;	/* address family */
38 	unsigned char	rtm_dst_len;	/* Prefix length */
39 	unsigned char	rtm_src_len;	/* Source prefix length (not used) */
40 	unsigned char	rtm_tos;	/* Type of service (not used) */
41 	unsigned char	rtm_table;	/* rtable id */
42 	unsigned char	rtm_protocol;	/* Routing protocol id (RTPROT_) */
43 	unsigned char	rtm_scope;	/* Route distance (RT_SCOPE_) */
44 	unsigned char	rtm_type;	/* Route type (RTN_) */
45 	unsigned 	rtm_flags;	/* Route flags (RTM_F_) */
46 };
47 
48 /*
49  * RFC 3549, 3.1.1, route type (rtm_type field).
50  */
51 enum {
52 	RTN_UNSPEC,
53 	RTN_UNICAST,		/* Unicast route */
54 	RTN_LOCAL,		/* Accept locally (not supported) */
55 	RTN_BROADCAST,		/* Accept locally as broadcast, send as broadcast */
56 	RTN_ANYCAST,		/* Accept locally as broadcast, but send as unicast */
57 	RTN_MULTICAST,		/* Multicast route */
58 	RTN_BLACKHOLE,		/* Drop traffic towards destination */
59 	RTN_UNREACHABLE,	/* Destination is unreachable */
60 	RTN_PROHIBIT,		/* Administratively prohibited */
61 	RTN_THROW,		/* Not in this table (not supported) */
62 	RTN_NAT,		/* Translate this address (not supported) */
63 	RTN_XRESOLVE,		/* Use external resolver (not supported) */
64 	__RTN_MAX,
65 };
66 #define RTN_MAX (__RTN_MAX - 1)
67 
68 /*
69  * RFC 3549, 3.1.1, protocol (Identifies what/who added the route).
70  * Values larger than RTPROT_STATIC(4) are not interpreted by the
71  * kernel, they are just for user information.
72  */
73 #define	RTPROT_UNSPEC		0
74 #define RTPROT_REDIRECT		1 /* Route installed by ICMP redirect */
75 #define RTPROT_KERNEL		2 /* Route installed by kernel */
76 #define RTPROT_BOOT		3 /* Route installed during boot */
77 #define RTPROT_STATIC		4 /* Route installed by administrator */
78 
79 #define	RTPROT_GATED		8
80 #define RTPROT_RA		9
81 #define RTPROT_MRT		1
82 #define RTPROT_ZEBRA		11
83 #define RTPROT_BIRD		12
84 #define RTPROT_DNROUTED		13
85 #define RTPROT_XORP		14
86 #define RTPROT_NTK		15
87 #define RTPROT_DHCP		16
88 #define RTPROT_MROUTED		17
89 #define RTPROT_KEEPALIVED	18
90 #define RTPROT_BABEL		42
91 #define RTPROT_OPENR		99
92 #define RTPROT_BGP		186
93 #define RTPROT_ISIS		187
94 #define RTPROT_OSPF		188
95 #define RTPROT_RIP		189
96 #define RTPROT_EIGRP		192
97 
98 /*
99  * RFC 3549 3.1.1 Route scope (valid distance to destination).
100  *
101  * The values between RT_SCOPE_UNIVERSE(0) and RT_SCOPE_SITE(200)
102  *  are available to the user.
103  */
104 enum rt_scope_t {
105 	RT_SCOPE_UNIVERSE = 0,
106 	/* User defined values  */
107 	RT_SCOPE_SITE = 200,
108 	RT_SCOPE_LINK = 253,
109 	RT_SCOPE_HOST = 254,
110 	RT_SCOPE_NOWHERE = 255
111 };
112 
113 /*
114  * RFC 3549 3.1.1 Route flags (rtm_flags).
115  * Is a composition of RTNH_F flags (0x1..0x40 range), RTM_F flags (below)
116  * and per-protocol (IPv4/IPv6) flags.
117  */
118 #define RTM_F_NOTIFY		0x00000100 /* not supported */
119 #define RTM_F_CLONED		0x00000200 /* not supported */
120 #define RTM_F_EQUALIZE		0x00000400 /* not supported */
121 #define RTM_F_PREFIX		0x00000800 /* not supported */
122 #define RTM_F_LOOKUP_TABLE	0x00001000 /* not supported */
123 #define RTM_F_FIB_MATCH		0x00002000 /* not supported */
124 #define RTM_F_OFFLOAD		0x00004000 /* not supported */
125 #define RTM_F_TRAP		0x00008000 /* not supported */
126 #define RTM_F_OFFLOAD_FAILED	0x20000000 /* not supported */
127 
128 /* Compatibility handling helpers */
129 #ifndef _KERNEL
130 #define	NL_RTM_HDRLEN		((int)sizeof(struct rtmsg))
131 #define	RTM_RTA(_rtm)		((struct rtattr *)((char *)(_rtm) + NL_RTM_HDRLEN))
132 #define	RTM_PAYLOAD(_hdr)	NLMSG_PAYLOAD((_hdr), NL_RTM_HDRLEN)
133 #endif
134 
135 /*
136  * Routing table identifiers.
137  * FreeBSD route table numbering starts from 0, where 0 is a valid default routing table.
138  * Indicating "all tables" via netlink can be done by not including RTA_TABLE attribute
139  * and keeping rtm_table=0 (compatibility) or setting RTA_TABLE value to RT_TABLE_UNSPEC.
140  */
141 #define	RT_TABLE_MAIN	0		/* RT_DEFAULT_FIB */
142 #define	RT_TABLE_UNSPEC	0xFFFFFFFF	/* RT_ALL_FIBS */
143 
144 enum rtattr_type_t {
145 	NL_RTA_UNSPEC,
146 	NL_RTA_DST		= 1, /* binary, IPv4/IPv6 destination */
147 	NL_RTA_SRC		= 2, /* binary, preferred source address */
148 	NL_RTA_IIF		= 3, /* not supported */
149 	NL_RTA_OIF		= 4, /* u32, transmit ifindex */
150 	NL_RTA_GATEWAY		= 5, /* binary: IPv4/IPv6 gateway */
151 	NL_RTA_PRIORITY		= 6, /* not supported */
152 	NL_RTA_PREFSRC		= 7, /* not supported */
153 	NL_RTA_METRICS		= 8, /* nested, list of NL_RTAX* attrs */
154 	NL_RTA_MULTIPATH	= 9, /* binary, array of struct rtnexthop */
155 	NL_RTA_PROTOINFO	= 10, /* not supported / deprecated */
156 	NL_RTA_KNH_ID		= 10, /* u32, FreeBSD specific, kernel nexthop index */
157 	NL_RTA_FLOW		= 11, /* not supported */
158 	NL_RTA_CACHEINFO	= 12, /* not supported */
159 	NL_RTA_SESSION		= 13, /* not supported / deprecated */
160 	NL_RTA_WEIGHT		= 13, /* u32, FreeBSD specific, path weight */
161 	NL_RTA_MP_ALGO		= 14, /* not supported / deprecated */
162 	NL_RTA_RTFLAGS		= 14, /* u32, FreeBSD specific, path flags (RTF_)*/
163 	NL_RTA_TABLE		= 15, /* u32, fibnum */
164 	NL_RTA_MARK		= 16, /* not supported */
165 	NL_RTA_MFC_STATS	= 17, /* not supported */
166 	NL_RTA_VIA		= 18, /* binary, struct rtvia */
167 	NL_RTA_NEWDST		= 19, /* not supported */
168 	NL_RTA_PREF		= 20, /* not supported */
169 	NL_RTA_ENCAP_TYPE	= 21, /* not supported */
170 	NL_RTA_ENCAP		= 22, /* not supported */
171 	NL_RTA_EXPIRES		= 23, /* u32, seconds till expiration */
172 	NL_RTA_PAD		= 24, /* not supported */
173 	NL_RTA_UID		= 25, /* not supported */
174 	NL_RTA_TTL_PROPAGATE	= 26, /* not supported */
175 	NL_RTA_IP_PROTO		= 27, /* not supported */
176 	NL_RTA_SPORT		= 28, /* not supported */
177 	NL_RTA_DPORT		= 29, /* not supported */
178 	NL_RTA_NH_ID		= 30, /* u32, nexthop/nexthop group index */
179 	__RTA_MAX
180 };
181 #define NL_RTA_MAX (__RTA_MAX - 1)
182 
183 /*
184  * Attributes that can be used as filters:
185  *
186  */
187 
188 #ifndef _KERNEL
189 /*
190  * RTA_* space has clashes with rtsock namespace.
191  * Use NL_RTA_ prefix in the kernel and map to
192  * RTA_ for userland.
193  */
194 #define RTA_UNSPEC		NL_RTA_UNSPEC
195 #define RTA_DST			NL_RTA_DST
196 #define RTA_SRC			NL_RTA_SRC
197 #define RTA_IIF			NL_RTA_IIF
198 #define RTA_OIF			NL_RTA_OIF
199 #define RTA_GATEWAY		NL_RTA_GATEWAY
200 #define RTA_PRIORITY		NL_RTA_PRIORITY
201 #define RTA_PREFSRC		NL_RTA_PREFSRC
202 #define RTA_METRICS		NL_RTA_METRICS
203 #define RTA_MULTIPATH		NL_RTA_MULTIPATH
204 #define	RTA_PROTOINFO		NL_RTA_PROTOINFO
205 #define	RTA_KNH_ID		NL_RTA_KNH_ID
206 #define RTA_FLOW		NL_RTA_FLOW
207 #define RTA_CACHEINFO		NL_RTA_CACHEINFO
208 #define	RTA_SESSION		NL_RTA_SESSION
209 #define	RTA_MP_ALGO		NL_RTA_MP_ALGO
210 #define RTA_TABLE		NL_RTA_TABLE
211 #define RTA_MARK		NL_RTA_MARK
212 #define RTA_MFC_STATS		NL_RTA_MFC_STATS
213 #define RTA_VIA			NL_RTA_VIA
214 #define RTA_NEWDST		NL_RTA_NEWDST
215 #define RTA_PREF		NL_RTA_PREF
216 #define RTA_ENCAP_TYPE		NL_RTA_ENCAP_TYPE
217 #define RTA_ENCAP		NL_RTA_ENCAP
218 #define RTA_EXPIRES		NL_RTA_EXPIRES
219 #define RTA_PAD			NL_RTA_PAD
220 #define RTA_UID			NL_RTA_UID
221 #define RTA_TTL_PROPAGATE	NL_RTA_TTL_PROPAGATE
222 #define RTA_IP_PROTO		NL_RTA_IP_PROTO
223 #define RTA_SPORT		NL_RTA_SPORT
224 #define RTA_DPORT		NL_RTA_DPORT
225 #define RTA_NH_ID		NL_RTA_NH_ID
226 #define	RTA_MAX			NL_RTA_MAX
227 #endif
228 
229 /* route attribute header */
230 struct rtattr {
231 	unsigned short rta_len;
232 	unsigned short rta_type;
233 };
234 
235 #define	NL_RTA_ALIGN_SIZE	NL_ITEM_ALIGN_SIZE
236 #define	NL_RTA_ALIGN		NL_ITEM_ALIGN
237 #define	NL_RTA_HDRLEN		((int)sizeof(struct rtattr))
238 #define	NL_RTA_DATA_LEN(_rta)	((int)((_rta)->rta_len - NL_RTA_HDRLEN))
239 #define	NL_RTA_DATA(_rta)	NL_ITEM_DATA(_rta, NL_RTA_HDRLEN)
240 #define	NL_RTA_DATA_CONST(_rta)	NL_ITEM_DATA_CONST(_rta, NL_RTA_HDRLEN)
241 
242 /* Compatibility attribute handling helpers */
243 #ifndef _KERNEL
244 #define	RTA_ALIGNTO		NL_RTA_ALIGN_SIZE
245 #define	RTA_ALIGN(_len)		NL_RTA_ALIGN(_len)
246 #define	_RTA_LEN(_rta)		((int)(_rta)->rta_len)
247 #define	_RTA_ALIGNED_LEN(_rta)	RTA_ALIGN(_RTA_LEN(_rta))
248 #define	RTA_OK(_rta, _len)	NL_ITEM_OK(_rta, _len, NL_RTA_HDRLEN, _RTA_LEN)
249 #define	RTA_NEXT(_rta, _len)	NL_ITEM_ITER(_rta, _len, _RTA_ALIGNED_LEN)
250 #define	RTA_LENGTH(_len)	(NL_RTA_HDRLEN + (_len))
251 #define	RTA_SPACE(_len)		RTA_ALIGN(RTA_LENGTH(_len))
252 #define	RTA_DATA(_rta)		NL_RTA_DATA(_rta)
253 #define	RTA_PAYLOAD(_rta)	((int)(_RTA_LEN(_rta) - NL_RTA_HDRLEN))
254 #endif
255 
256 /* RTA attribute headers */
257 
258 /* RTA_VIA */
259 struct rtvia {
260 	sa_family_t	rtvia_family;
261 	uint8_t		rtvia_addr[0];
262 };
263 
264 /*
265  * RTA_METRICS is a nested attribute, consisting of a list of
266  * TLVs with types defined below.
267  */
268  enum {
269 	NL_RTAX_UNSPEC,
270 	NL_RTAX_LOCK			= 1, /* not supported */
271 	NL_RTAX_MTU			= 2, /* desired path MTU */
272 	NL_RTAX_WINDOW			= 3, /* not supported */
273 	NL_RTAX_RTT			= 4, /* not supported */
274 	NL_RTAX_RTTVAR			= 5, /* not supported */
275 	NL_RTAX_SSTHRESH		= 6, /* not supported */
276 	NL_RTAX_CWND			= 7, /* not supported */
277 	NL_RTAX_ADVMSS			= 8, /* not supported  */
278 	NL_RTAX_REORDERING		= 9, /* not supported */
279 	NL_RTAX_HOPLIMIT		= 10, /* not supported */
280 	NL_RTAX_INITCWND		= 11, /* not supporrted */
281 	NL_RTAX_FEATURES		= 12, /* not supported */
282 	NL_RTAX_RTO_MIN			= 13, /* not supported */
283 	NL_RTAX_INITRWND		= 14, /* not supported */
284 	NL_RTAX_QUICKACK		= 15, /* not supported */
285 	NL_RTAX_CC_ALGO			= 15, /* not supported */
286 	NL_RTAX_FASTOPEN_NO_COOKIE	= 16, /* not supported */
287 	__NL_RTAX_MAX
288 };
289 #define NL_RTAX_MAX (__NL_RTAX_MAX - 1)
290 
291 #define RTAX_FEATURE_ECN (1 << 0)
292 #define RTAX_FEATURE_SACK (1 << 1)
293 #define RTAX_FEATURE_TIMESTAMP (1 << 2)
294 #define RTAX_FEATURE_ALLFRAG (1 << 3)
295 
296 #define RTAX_FEATURE_MASK                                                \
297 	(RTAX_FEATURE_ECN | RTAX_FEATURE_SACK | RTAX_FEATURE_TIMESTAMP | \
298 	    RTAX_FEATURE_ALLFRAG)
299 
300 #ifndef _KERNEL
301 
302 /*
303  * RTAX_* space clashes with rtsock namespace.
304  * Use NL_RTAX_ prefix in the kernel and map to
305  * RTAX_ for userland.
306  */
307 #define RTAX_UNSPEC		NL_RTAX_UNSPEC
308 #define RTAX_LOCK		NL_RTAX_LOCK
309 #define RTAX_MTU		NL_RTAX_MTU
310 #define RTAX_WINDOW		NL_RTAX_WINDOW
311 #define RTAX_RTT		NL_RTAX_RTT
312 #define RTAX_RTTVAR		NL_RTAX_RTTVAR
313 #define RTAX_SSTHRESH		NL_RTAX_SSTHRESH
314 #define RTAX_CWND		NL_RTAX_CWND
315 #define RTAX_ADVMSS		NL_RTAX_ADVMSS
316 #define RTAX_REORDERING		NL_RTAX_REORDERING
317 #define RTAX_HOPLIMIT		NL_RTAX_HOPLIMIT
318 #define RTAX_INITCWND		NL_RTAX_INITCWND
319 #define RTAX_FEATURES		NL_RTAX_FEATURES
320 #define RTAX_RTO_MIN		NL_RTAX_RTO_MIN
321 #define RTAX_INITRWND		NL_RTAX_INITRWND
322 #define RTAX_QUICKACK		NL_RTAX_QUICKACK
323 #define RTAX_CC_ALGO		NL_RTAX_CC_ALGO
324 #define RTAX_FASTOPEN_NO_COOKIE	NL_RTAX_FASTOPEN_NO_COOKIE
325 #endif
326 
327 /*
328  * RTA_MULTIPATH consists of an array of rtnexthop structures.
329  * Each rtnexthop structure contains RTA_GATEWAY or RTA_VIA
330  * attribute following the header.
331  */
332 struct rtnexthop {
333 	unsigned short		rtnh_len;
334 	unsigned char		rtnh_flags;
335 	unsigned char		rtnh_hops;	/* nexthop weight */
336 	int			rtnh_ifindex;
337 };
338 
339 /* rtnh_flags */
340 #define RTNH_F_DEAD		0x01	/* not supported */
341 #define RTNH_F_PERVASIVE	0x02	/* not supported */
342 #define RTNH_F_ONLINK		0x04	/* not supported */
343 #define RTNH_F_OFFLOAD		0x08	/* not supported */
344 #define RTNH_F_LINKDOWN		0x10	/* not supported */
345 #define RTNH_F_UNRESOLVED	0x20	/* not supported */
346 #define RTNH_F_TRAP		0x40	/* not supported */
347 
348 #define RTNH_COMPARE_MASK	(RTNH_F_DEAD | RTNH_F_LINKDOWN | \
349 				 RTNH_F_OFFLOAD | RTNH_F_TRAP)
350 
351 /* Macros to handle hexthops */
352 #define	RTNH_ALIGNTO		NL_ITEM_ALIGN_SIZE
353 #define	RTNH_ALIGN(_len)	NL_ITEM_ALIGN(_len)
354 #define	RTNH_HDRLEN		((int)sizeof(struct rtnexthop))
355 #define	_RTNH_LEN(_nh)		((int)(_nh)->rtnh_len)
356 #define	_RTNH_ALIGNED_LEN(_nh)	RTNH_ALIGN(_RTNH_LEN(_nh))
357 #define	RTNH_OK(_nh, _len)	NL_ITEM_OK(_nh, _len, RTNH_HDRLEN, _RTNH_LEN)
358 #define	RTNH_NEXT(_nh)		((struct rtnexthop *)((char *)(_nh) + _RTNH_ALIGNED_LEN(_nh)))
359 #define	RTNH_LENGTH(_len)	(RTNH_HDRLEN + (_len))
360 #define	RTNH_SPACE(_len)	RTNH_ALIGN(RTNH_LENGTH(_len))
361 #define	RTNH_DATA(_nh)		((struct rtattr *)NL_ITEM_DATA(_nh, RTNH_HDRLEN))
362 
363 struct rtgenmsg {
364 	unsigned char rtgen_family;
365 };
366 
367 #endif
368