xref: /netbsd-src/sys/net/if_ether.h (revision 481fca6e59249d8ffcf24fef7cfbe7b131bfb080)
1 /*	$NetBSD: if_ether.h,v 1.17 2000/06/17 20:57:20 matt 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  * Ethernet address - 6 octets
53  * this is only used by the ethers(3) functions.
54  */
55 struct ether_addr {
56 	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
57 } __attribute__((__packed__));
58 
59 /*
60  * Structure of a 10Mb/s Ethernet header.
61  */
62 struct	ether_header {
63 	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
64 	u_int8_t  ether_shost[ETHER_ADDR_LEN];
65 	u_int16_t ether_type;
66 } __attribute__((__packed__));
67 
68 #include <net/ethertypes.h>
69 
70 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
71 
72 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
73 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
74 
75 /*
76  * Ethernet CRC32 polynomials (big- and little-endian verions).
77  */
78 #define	ETHER_CRC_POLY_LE	0xedb88320
79 #define	ETHER_CRC_POLY_BE	0x04c11db6
80 
81 #ifndef _STANDALONE
82 
83 /*
84  * Ethernet-specific mbuf flags.
85  */
86 #define	M_HASFCS	M_LINK0		/* FCS included at end of frame */
87 
88 #ifdef _KERNEL
89 /*
90  * Macro to map an IP multicast address to an Ethernet multicast address.
91  * The high-order 25 bits of the Ethernet address are statically assigned,
92  * and the low-order 23 bits are taken from the low end of the IP address.
93  */
94 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
95 	/* struct in_addr *ipaddr; */					\
96 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
97 {									\
98 	(enaddr)[0] = 0x01;						\
99 	(enaddr)[1] = 0x00;						\
100 	(enaddr)[2] = 0x5e;						\
101 	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
102 	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
103 	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
104 }
105 /*
106  * Macro to map an IP6 multicast address to an Ethernet multicast address.
107  * The high-order 16 bits of the Ethernet address are statically assigned,
108  * and the low-order 32 bits are taken from the low end of the IP6 address.
109  */
110 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
111 	/* struct in6_addr *ip6addr; */					\
112 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
113 {                                                                       \
114 	(enaddr)[0] = 0x33;						\
115 	(enaddr)[1] = 0x33;						\
116 	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
117 	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
118 	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
119 	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
120 }
121 #endif
122 
123 /*
124  * Structure shared between the ethernet driver modules and
125  * the multicast list code.  For example, each ec_softc or il_softc
126  * begins with this structure.
127  */
128 struct	ethercom {
129 	struct	 ifnet ec_if;			/* network-visible interface */
130 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast addrs */
131 	int	 ec_multicnt;			/* length of ec_multiaddrs list */
132 };
133 
134 #ifdef	_KERNEL
135 extern u_int8_t etherbroadcastaddr[ETHER_ADDR_LEN];
136 extern u_int8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
137 extern u_int8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
138 
139 int	ether_addmulti (struct ifreq *, struct ethercom *);
140 int	ether_delmulti (struct ifreq *, struct ethercom *);
141 int	ether_changeaddr (struct ifreq *, struct ethercom *);
142 #endif /* _KERNEL */
143 
144 /*
145  * Ethernet multicast address structure.  There is one of these for each
146  * multicast address or range of multicast addresses that we are supposed
147  * to listen to on a particular interface.  They are kept in a linked list,
148  * rooted in the interface's ethercom structure.
149  */
150 struct ether_multi {
151 	u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
152 	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
153 	struct	 ethercom *enm_ec;	/* back pointer to ethercom */
154 	u_int	 enm_refcount;		/* no. claims to this addr/range */
155 	LIST_ENTRY(ether_multi) enm_list;
156 };
157 
158 /*
159  * Structure used by macros below to remember position when stepping through
160  * all of the ether_multi records.
161  */
162 struct ether_multistep {
163 	struct ether_multi  *e_enm;
164 };
165 
166 /*
167  * Macro for looking up the ether_multi record for a given range of Ethernet
168  * multicast addresses connected to a given ethercom structure.  If no matching
169  * record is found, "enm" returns NULL.
170  */
171 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
172 	/* u_int8_t addrlo[ETHER_ADDR_LEN]; */				\
173 	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
174 	/* struct ethercom *ec; */					\
175 	/* struct ether_multi *enm; */					\
176 {									\
177 	for ((enm) = (ec)->ec_multiaddrs.lh_first;			\
178 	    (enm) != NULL &&						\
179 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
180 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
181 		(enm) = (enm)->enm_list.le_next);			\
182 }
183 
184 /*
185  * Macro to step through all of the ether_multi records, one at a time.
186  * The current position is remembered in "step", which the caller must
187  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
188  * and get the first record.  Both macros return a NULL "enm" when there
189  * are no remaining records.
190  */
191 #define ETHER_NEXT_MULTI(step, enm) \
192 	/* struct ether_multistep step; */  \
193 	/* struct ether_multi *enm; */  \
194 { \
195 	if (((enm) = (step).e_enm) != NULL) \
196 		(step).e_enm = (enm)->enm_list.le_next; \
197 }
198 
199 #define ETHER_FIRST_MULTI(step, ec, enm) \
200 	/* struct ether_multistep step; */ \
201 	/* struct ethercom *ec; */ \
202 	/* struct ether_multi *enm; */ \
203 { \
204 	(step).e_enm = (ec)->ec_multiaddrs.lh_first; \
205 	ETHER_NEXT_MULTI((step), (enm)); \
206 }
207 
208 #ifdef _KERNEL
209 u_int32_t ether_crc32_le (const u_int8_t *, size_t);
210 u_int32_t ether_crc32_be (const u_int8_t *, size_t);
211 #else
212 /*
213  * Prototype ethers(3) functions.
214  */
215 #include <sys/cdefs.h>
216 __BEGIN_DECLS
217 char *	ether_ntoa __P((struct ether_addr *));
218 struct ether_addr *
219 	ether_aton __P((const char *));
220 int	ether_ntohost __P((char *, struct ether_addr *));
221 int	ether_hostton __P((const char *, struct ether_addr *));
222 int	ether_line __P((const char *, struct ether_addr *, char *));
223 __END_DECLS
224 #endif
225 
226 #endif /* _STANDALONE */
227 
228 #endif /* _NET_IF_ETHER_H_ */
229