xref: /openbsd/sys/netinet/if_ether.h (revision 09467b48)
1 /*	$OpenBSD: if_ether.h,v 1.78 2020/07/22 02:16:02 dlg Exp $	*/
2 /*	$NetBSD: if_ether.h,v 1.22 1996/05/11 13:00:00 mycroft Exp $	*/
3 
4 /*
5  * Copyright (c) 1982, 1986, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  * 3. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
33  */
34 
35 #ifndef _NETINET_IF_ETHER_H_
36 #define _NETINET_IF_ETHER_H_
37 
38 /*
39  * Some basic Ethernet constants.
40  */
41 #define	ETHER_ADDR_LEN	6	/* Ethernet address length		*/
42 #define ETHER_TYPE_LEN	2	/* Ethernet type field length		*/
43 #define ETHER_CRC_LEN	4	/* Ethernet CRC length			*/
44 #define ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
45 #define ETHER_MIN_LEN	64	/* Minimum frame length, CRC included	*/
46 #define ETHER_MAX_LEN	1518	/* Maximum frame length, CRC included	*/
47 #define ETHER_MAX_DIX_LEN	1536	/* Maximum DIX frame length	*/
48 
49 /*
50  * Some Ethernet extensions.
51  */
52 #define ETHER_VLAN_ENCAP_LEN	4	/* len of 802.1Q VLAN encapsulation */
53 
54 /*
55  * Mbuf adjust factor to force 32-bit alignment of IP header.
56  * Drivers should do m_adj(m, ETHER_ALIGN) when setting up a
57  * receive so the upper layers get the IP header properly aligned
58  * past the 14-byte Ethernet header.
59  */
60 #define ETHER_ALIGN	2	/* driver adjust for IP hdr alignment */
61 
62 /*
63  * The maximum supported Ethernet length and some space for encapsulation.
64  */
65 #define ETHER_MAX_HARDMTU_LEN	65435
66 
67 /*
68  * Ethernet address - 6 octets
69  */
70 struct ether_addr {
71 	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
72 };
73 
74 /*
75  * The length of the combined header.
76  */
77 struct	ether_header {
78 	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
79 	u_int8_t  ether_shost[ETHER_ADDR_LEN];
80 	u_int16_t ether_type;
81 };
82 
83 /*
84  * VLAN headers.
85  */
86 
87 struct  ether_vlan_header {
88         u_char  evl_dhost[ETHER_ADDR_LEN];
89         u_char  evl_shost[ETHER_ADDR_LEN];
90         u_int16_t evl_encap_proto;
91         u_int16_t evl_tag;
92         u_int16_t evl_proto;
93 };
94 
95 #define EVL_VLID_MASK	0xFFF
96 #define EVL_VLID_NULL	0x000
97 /* 0x000 and 0xfff are reserved */
98 #define EVL_VLID_MIN	0x001
99 #define EVL_VLID_MAX	0xFFE
100 #define EVL_VLANOFTAG(tag) ((tag) & EVL_VLID_MASK)
101 
102 #define EVL_PRIO_MAX    7
103 #define EVL_PRIO_BITS   13
104 #define EVL_PRIOFTAG(tag) (((tag) >> EVL_PRIO_BITS) & 7)
105 
106 #define EVL_ENCAPLEN    4       /* length in octets of encapsulation */
107 
108 #include <net/ethertypes.h>
109 
110 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
111 #define	ETHER_IS_BROADCAST(addr) \
112 	(((addr)[0] & (addr)[1] & (addr)[2] & \
113 	  (addr)[3] & (addr)[4] & (addr)[5]) == 0xff)
114 #define	ETHER_IS_ANYADDR(addr)		\
115 	(((addr)[0] | (addr)[1] | (addr)[2] | \
116 	  (addr)[3] | (addr)[4] | (addr)[5]) == 0x00)
117 #define	ETHER_IS_EQ(a1, a2)	(memcmp((a1), (a2), ETHER_ADDR_LEN) == 0)
118 
119 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
120 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
121 
122 /*
123  * Ethernet CRC32 polynomials (big- and little-endian verions).
124  */
125 #define	ETHER_CRC_POLY_LE	0xedb88320
126 #define	ETHER_CRC_POLY_BE	0x04c11db6
127 
128 /*
129  * Ethernet Address Resolution Protocol.
130  *
131  * See RFC 826 for protocol description.  Structure below is adapted
132  * to resolving internet addresses.  Field names used correspond to
133  * RFC 826.
134  */
135 struct	ether_arp {
136 	struct	 arphdr ea_hdr;			/* fixed-size header */
137 	u_int8_t arp_sha[ETHER_ADDR_LEN];	/* sender hardware address */
138 	u_int8_t arp_spa[4];			/* sender protocol address */
139 	u_int8_t arp_tha[ETHER_ADDR_LEN];	/* target hardware address */
140 	u_int8_t arp_tpa[4];			/* target protocol address */
141 };
142 #define	arp_hrd	ea_hdr.ar_hrd
143 #define	arp_pro	ea_hdr.ar_pro
144 #define	arp_hln	ea_hdr.ar_hln
145 #define	arp_pln	ea_hdr.ar_pln
146 #define	arp_op	ea_hdr.ar_op
147 
148 struct sockaddr_inarp {
149 	u_int8_t  sin_len;
150 	u_int8_t  sin_family;
151 	u_int16_t sin_port;
152 	struct	  in_addr sin_addr;
153 	struct	  in_addr sin_srcaddr;
154 	u_int16_t sin_tos;
155 	u_int16_t sin_other;
156 #define SIN_PROXY 1
157 };
158 
159 /*
160  * IP and ethernet specific routing flags
161  */
162 #define	RTF_USETRAILERS	  RTF_PROTO1	/* use trailers */
163 #define	RTF_PERMANENT_ARP RTF_PROTO3    /* only manual overwrite of entry */
164 
165 #ifdef _KERNEL
166 /*
167  * Macro to map an IP multicast address to an Ethernet multicast address.
168  * The high-order 25 bits of the Ethernet address are statically assigned,
169  * and the low-order 23 bits are taken from the low end of the IP address.
170  */
171 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
172 	/* struct in_addr *ipaddr; */					\
173 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
174 do {									\
175 	(enaddr)[0] = 0x01;						\
176 	(enaddr)[1] = 0x00;						\
177 	(enaddr)[2] = 0x5e;						\
178 	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
179 	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
180 	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
181 } while (/* CONSTCOND */ 0)
182 
183 /*
184  * Macro to map an IPv6 multicast address to an Ethernet multicast address.
185  * The high-order 16 bits of the Ethernet address are statically assigned,
186  * and the low-order 32 bits are taken from the low end of the IPv6 address.
187  */
188 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
189 	/* struct in6_addr *ip6addr; */					\
190 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
191 do {									\
192 	(enaddr)[0] = 0x33;						\
193 	(enaddr)[1] = 0x33;						\
194 	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
195 	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
196 	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
197 	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
198 } while (/* CONSTCOND */ 0)
199 
200 #include <net/if_var.h>	/* for "struct ifnet" */
201 
202 struct ether_brport {
203 	struct mbuf	*(*eb_input)(struct ifnet *, struct mbuf *, void *);
204 	void		  *eb_port;
205 };
206 
207 /*
208  * Structure shared between the ethernet driver modules and
209  * the address resolution code.  For example, each ec_softc or il_softc
210  * begins with this structure.
211  */
212 struct	arpcom {
213 	struct	 ifnet ac_if;			/* network-visible interface */
214 	u_int8_t ac_enaddr[ETHER_ADDR_LEN];	/* ethernet hardware address */
215 	char	 ac__pad[2];			/* pad for some machines */
216 	LIST_HEAD(, ether_multi) ac_multiaddrs;	/* list of multicast addrs */
217 	int	 ac_multicnt;			/* length of ac_multiaddrs */
218 	int	 ac_multirangecnt;		/* number of mcast ranges */
219 
220 	void	*ac_trunkport;
221 	const struct ether_brport *ac_brport;
222 };
223 
224 extern int arpt_keep;				/* arp resolved cache expire */
225 extern int arpt_down;				/* arp down cache expire */
226 
227 extern u_int8_t etherbroadcastaddr[ETHER_ADDR_LEN];
228 extern u_int8_t etheranyaddr[ETHER_ADDR_LEN];
229 extern u_int8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
230 extern u_int8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
231 
232 #ifdef NFSCLIENT
233 extern unsigned int revarp_ifidx;
234 #endif /* NFSCLIENT */
235 
236 void	revarpinput(struct ifnet *, struct mbuf *);
237 void	revarprequest(struct ifnet *);
238 int	revarpwhoarewe(struct ifnet *, struct in_addr *, struct in_addr *);
239 int	revarpwhoami(struct in_addr *, struct ifnet *);
240 
241 void	arpinput(struct ifnet *, struct mbuf *);
242 void	arprequest(struct ifnet *, u_int32_t *, u_int32_t *, u_int8_t *);
243 void	arpwhohas(struct arpcom *, struct in_addr *);
244 int	arpproxy(struct in_addr, unsigned int);
245 int	arpresolve(struct ifnet *, struct rtentry *, struct mbuf *,
246 	    struct sockaddr *, u_char *);
247 void	arp_rtrequest(struct ifnet *, int, struct rtentry *);
248 
249 void	ether_fakeaddr(struct ifnet *);
250 int	ether_addmulti(struct ifreq *, struct arpcom *);
251 int	ether_delmulti(struct ifreq *, struct arpcom *);
252 int	ether_multiaddr(struct sockaddr *, u_int8_t[], u_int8_t[]);
253 void	ether_ifattach(struct ifnet *);
254 void	ether_ifdetach(struct ifnet *);
255 int	ether_ioctl(struct ifnet *, struct arpcom *, u_long, caddr_t);
256 void	ether_input(struct ifnet *, struct mbuf *);
257 int	ether_resolve(struct ifnet *, struct mbuf *, struct sockaddr *,
258 	    struct rtentry *, struct ether_header *);
259 struct mbuf *
260 	ether_encap(struct ifnet *, struct mbuf *, struct sockaddr *,
261 	    struct rtentry *, int *);
262 int	ether_output(struct ifnet *, struct mbuf *, struct sockaddr *,
263 	    struct rtentry *);
264 void	ether_rtrequest(struct ifnet *, int, struct rtentry *);
265 char	*ether_sprintf(u_char *);
266 
267 int	ether_brport_isset(struct ifnet *);
268 void	ether_brport_set(struct ifnet *, const struct ether_brport *);
269 void	ether_brport_clr(struct ifnet *);
270 const struct ether_brport *
271 	ether_brport_get(struct ifnet *);
272 const struct ether_brport *
273 	ether_brport_get_locked(struct ifnet *);
274 
275 /*
276  * Ethernet multicast address structure.  There is one of these for each
277  * multicast address or range of multicast addresses that we are supposed
278  * to listen to on a particular interface.  They are kept in a linked list,
279  * rooted in the interface's arpcom structure.  (This really has nothing to
280  * do with ARP, or with the Internet address family, but this appears to be
281  * the minimally-disrupting place to put it.)
282  */
283 struct ether_multi {
284 	u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
285 	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
286 	u_int	 enm_refcount;		/* no. claims to this addr/range */
287 	LIST_ENTRY(ether_multi) enm_list;
288 };
289 
290 /*
291  * Structure used by macros below to remember position when stepping through
292  * all of the ether_multi records.
293  */
294 struct ether_multistep {
295 	struct ether_multi  *e_enm;
296 };
297 
298 /*
299  * Macro for looking up the ether_multi record for a given range of Ethernet
300  * multicast addresses connected to a given arpcom structure.  If no matching
301  * record is found, "enm" returns NULL.
302  */
303 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm)			\
304 	/* u_int8_t addrlo[ETHER_ADDR_LEN]; */				\
305 	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
306 	/* struct arpcom *ac; */					\
307 	/* struct ether_multi *enm; */					\
308 do {									\
309 	for ((enm) = LIST_FIRST(&(ac)->ac_multiaddrs);			\
310 	    (enm) != NULL &&						\
311 	    (memcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||\
312 	     memcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
313 		(enm) = LIST_NEXT((enm), enm_list));			\
314 } while (/* CONSTCOND */ 0)
315 
316 /*
317  * Macro to step through all of the ether_multi records, one at a time.
318  * The current position is remembered in "step", which the caller must
319  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
320  * and get the first record.  Both macros return a NULL "enm" when there
321  * are no remaining records.
322  */
323 #define ETHER_NEXT_MULTI(step, enm)					\
324 	/* struct ether_multistep step; */				\
325 	/* struct ether_multi *enm; */					\
326 do {									\
327 	if (((enm) = (step).e_enm) != NULL)				\
328 		(step).e_enm = LIST_NEXT((enm), enm_list);		\
329 } while (/* CONSTCOND */ 0)
330 
331 #define ETHER_FIRST_MULTI(step, ac, enm)				\
332 	/* struct ether_multistep step; */				\
333 	/* struct arpcom *ac; */					\
334 	/* struct ether_multi *enm; */					\
335 do {									\
336 	(step).e_enm = LIST_FIRST(&(ac)->ac_multiaddrs);		\
337 	ETHER_NEXT_MULTI((step), (enm));				\
338 } while (/* CONSTCOND */ 0)
339 
340 u_int32_t ether_crc32_le_update(u_int32_t crc, const u_int8_t *, size_t);
341 u_int32_t ether_crc32_be_update(u_int32_t crc, const u_int8_t *, size_t);
342 u_int32_t ether_crc32_le(const u_int8_t *, size_t);
343 u_int32_t ether_crc32_be(const u_int8_t *, size_t);
344 
345 #else /* _KERNEL */
346 
347 __BEGIN_DECLS
348 char *ether_ntoa(struct ether_addr *);
349 struct ether_addr *ether_aton(const char *);
350 int ether_ntohost(char *, struct ether_addr *);
351 int ether_hostton(const char *, struct ether_addr *);
352 int ether_line(const char *, struct ether_addr *, char *);
353 __END_DECLS
354 
355 #endif /* _KERNEL */
356 #endif /* _NETINET_IF_ETHER_H_ */
357