xref: /netbsd-src/sys/net/if_ether.h (revision 5aefcfdc06931dd97e76246d2fe0302f7b3fe094)
1 /*	$NetBSD: if_ether.h,v 1.21 2000/11/17 19:21:53 bouyer Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the University of
18  *	California, Berkeley and its contributors.
19  * 4. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
36  */
37 
38 #ifndef _NET_IF_ETHER_H_
39 #define _NET_IF_ETHER_H_
40 
41 /*
42  * Some basic Ethernet constants.
43  */
44 #define	ETHER_ADDR_LEN	6	/* length of an Ethernet address */
45 #define	ETHER_TYPE_LEN	2	/* length of the Ethernet type field */
46 #define	ETHER_CRC_LEN	4	/* length of the Ethernet CRC */
47 #define	ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
48 #define	ETHER_MIN_LEN	64	/* minimum frame length, including CRC */
49 #define	ETHER_MAX_LEN	1518	/* maximum frame length, including CRC */
50 
51 /*
52  * Some Ethernet extensions.
53  */
54 #define	ETHER_VLAN_ENCAP_LEN 4	/* length of 802.1Q VLAN encapsulation */
55 
56 /*
57  * Ethernet address - 6 octets
58  * this is only used by the ethers(3) functions.
59  */
60 struct ether_addr {
61 	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
62 } __attribute__((__packed__));
63 
64 /*
65  * Structure of a 10Mb/s Ethernet header.
66  */
67 struct	ether_header {
68 	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
69 	u_int8_t  ether_shost[ETHER_ADDR_LEN];
70 	u_int16_t ether_type;
71 } __attribute__((__packed__));
72 
73 #include <net/ethertypes.h>
74 
75 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
76 
77 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
78 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
79 
80 /*
81  * Compute the maximum frame size based on ethertype (i.e. possible
82  * encapsulation) and whether or not an FCS is present.
83  */
84 #define	ETHER_MAX_FRAME(etype, hasfcs)					\
85 	(ETHERMTU + ETHER_HDR_LEN +					\
86 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
87 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0))
88 
89 /*
90  * Ethernet CRC32 polynomials (big- and little-endian verions).
91  */
92 #define	ETHER_CRC_POLY_LE	0xedb88320
93 #define	ETHER_CRC_POLY_BE	0x04c11db6
94 
95 #ifndef _STANDALONE
96 
97 /*
98  * Ethernet-specific mbuf flags.
99  */
100 #define	M_HASFCS	M_LINK0		/* FCS included at end of frame */
101 
102 #ifdef _KERNEL
103 /*
104  * Macro to map an IP multicast address to an Ethernet multicast address.
105  * The high-order 25 bits of the Ethernet address are statically assigned,
106  * and the low-order 23 bits are taken from the low end of the IP address.
107  */
108 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
109 	/* struct in_addr *ipaddr; */					\
110 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
111 {									\
112 	(enaddr)[0] = 0x01;						\
113 	(enaddr)[1] = 0x00;						\
114 	(enaddr)[2] = 0x5e;						\
115 	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
116 	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
117 	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
118 }
119 /*
120  * Macro to map an IP6 multicast address to an Ethernet multicast address.
121  * The high-order 16 bits of the Ethernet address are statically assigned,
122  * and the low-order 32 bits are taken from the low end of the IP6 address.
123  */
124 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
125 	/* struct in6_addr *ip6addr; */					\
126 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
127 {                                                                       \
128 	(enaddr)[0] = 0x33;						\
129 	(enaddr)[1] = 0x33;						\
130 	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
131 	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
132 	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
133 	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
134 }
135 #endif
136 
137 /*
138  * Structure shared between the ethernet driver modules and
139  * the multicast list code.  For example, each ec_softc or il_softc
140  * begins with this structure.
141  */
142 struct	ethercom {
143 	struct	 ifnet ec_if;			/* network-visible interface */
144 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
145 						   addrs */
146 	int	 ec_multicnt;			/* length of ec_multiaddrs
147 						   list */
148 	int	 ec_capabilities;		/* capabilities, provided by
149 						   driver */
150 	int	 ec_capenable;			/* tells hardware which
151 						   capabilities to enable */
152 
153 	int	 ec_nvlans;			/* # VLANs on this interface */
154 };
155 
156 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
157 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
158 
159 #ifdef	_KERNEL
160 extern u_int8_t etherbroadcastaddr[ETHER_ADDR_LEN];
161 extern u_int8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
162 extern u_int8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
163 
164 int	ether_ioctl(struct ifnet *, u_long, caddr_t);
165 int	ether_addmulti (struct ifreq *, struct ethercom *);
166 int	ether_delmulti (struct ifreq *, struct ethercom *);
167 int	ether_changeaddr (struct ifreq *, struct ethercom *);
168 int	ether_multiaddr(struct sockaddr *, u_int8_t[], u_int8_t[]);
169 #endif /* _KERNEL */
170 
171 /*
172  * Ethernet multicast address structure.  There is one of these for each
173  * multicast address or range of multicast addresses that we are supposed
174  * to listen to on a particular interface.  They are kept in a linked list,
175  * rooted in the interface's ethercom structure.
176  */
177 struct ether_multi {
178 	u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
179 	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
180 	struct	 ethercom *enm_ec;	/* back pointer to ethercom */
181 	u_int	 enm_refcount;		/* no. claims to this addr/range */
182 	LIST_ENTRY(ether_multi) enm_list;
183 };
184 
185 /*
186  * Structure used by macros below to remember position when stepping through
187  * all of the ether_multi records.
188  */
189 struct ether_multistep {
190 	struct ether_multi  *e_enm;
191 };
192 
193 /*
194  * Macro for looking up the ether_multi record for a given range of Ethernet
195  * multicast addresses connected to a given ethercom structure.  If no matching
196  * record is found, "enm" returns NULL.
197  */
198 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
199 	/* u_int8_t addrlo[ETHER_ADDR_LEN]; */				\
200 	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
201 	/* struct ethercom *ec; */					\
202 	/* struct ether_multi *enm; */					\
203 {									\
204 	for ((enm) = (ec)->ec_multiaddrs.lh_first;			\
205 	    (enm) != NULL &&						\
206 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
207 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
208 		(enm) = (enm)->enm_list.le_next);			\
209 }
210 
211 /*
212  * Macro to step through all of the ether_multi records, one at a time.
213  * The current position is remembered in "step", which the caller must
214  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
215  * and get the first record.  Both macros return a NULL "enm" when there
216  * are no remaining records.
217  */
218 #define ETHER_NEXT_MULTI(step, enm) \
219 	/* struct ether_multistep step; */  \
220 	/* struct ether_multi *enm; */  \
221 { \
222 	if (((enm) = (step).e_enm) != NULL) \
223 		(step).e_enm = (enm)->enm_list.le_next; \
224 }
225 
226 #define ETHER_FIRST_MULTI(step, ec, enm) \
227 	/* struct ether_multistep step; */ \
228 	/* struct ethercom *ec; */ \
229 	/* struct ether_multi *enm; */ \
230 { \
231 	(step).e_enm = (ec)->ec_multiaddrs.lh_first; \
232 	ETHER_NEXT_MULTI((step), (enm)); \
233 }
234 
235 #ifdef _KERNEL
236 u_int32_t ether_crc32_le (const u_int8_t *, size_t);
237 u_int32_t ether_crc32_be (const u_int8_t *, size_t);
238 #else
239 /*
240  * Prototype ethers(3) functions.
241  */
242 #include <sys/cdefs.h>
243 __BEGIN_DECLS
244 char *	ether_ntoa __P((struct ether_addr *));
245 struct ether_addr *
246 	ether_aton __P((const char *));
247 int	ether_ntohost __P((char *, struct ether_addr *));
248 int	ether_hostton __P((const char *, struct ether_addr *));
249 int	ether_line __P((const char *, struct ether_addr *, char *));
250 __END_DECLS
251 #endif
252 
253 #endif /* _STANDALONE */
254 
255 #endif /* _NET_IF_ETHER_H_ */
256