xref: /netbsd/sys/net/if_ether.h (revision bf9ec67e)
1 /*	$NetBSD: if_ether.h,v 1.27 2002/03/05 04:13:00 itojun 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 #define	ETHER_MAX_LEN_JUMBO 9018 /* maximum jumbo frame len, including CRC */
51 
52 /*
53  * Some Ethernet extensions.
54  */
55 #define	ETHER_VLAN_ENCAP_LEN 4	/* length of 802.1Q VLAN encapsulation */
56 
57 /*
58  * Ethernet address - 6 octets
59  * this is only used by the ethers(3) functions.
60  */
61 struct ether_addr {
62 	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
63 } __attribute__((__packed__));
64 
65 /*
66  * Structure of a 10Mb/s Ethernet header.
67  */
68 struct	ether_header {
69 	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
70 	u_int8_t  ether_shost[ETHER_ADDR_LEN];
71 	u_int16_t ether_type;
72 } __attribute__((__packed__));
73 
74 #include <net/ethertypes.h>
75 
76 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
77 
78 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
79 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
80 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
81 
82 /*
83  * Compute the maximum frame size based on ethertype (i.e. possible
84  * encapsulation) and whether or not an FCS is present.
85  */
86 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
87 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
88 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
89 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0))
90 
91 /*
92  * Ethernet CRC32 polynomials (big- and little-endian verions).
93  */
94 #define	ETHER_CRC_POLY_LE	0xedb88320
95 #define	ETHER_CRC_POLY_BE	0x04c11db6
96 
97 #ifndef _STANDALONE
98 
99 /*
100  * Ethernet-specific mbuf flags.
101  */
102 #define	M_HASFCS	M_LINK0		/* FCS included at end of frame */
103 
104 #ifdef _KERNEL
105 /*
106  * Macro to map an IP multicast address to an Ethernet multicast address.
107  * The high-order 25 bits of the Ethernet address are statically assigned,
108  * and the low-order 23 bits are taken from the low end of the IP address.
109  */
110 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
111 	/* struct in_addr *ipaddr; */					\
112 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
113 {									\
114 	(enaddr)[0] = 0x01;						\
115 	(enaddr)[1] = 0x00;						\
116 	(enaddr)[2] = 0x5e;						\
117 	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
118 	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
119 	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
120 }
121 /*
122  * Macro to map an IP6 multicast address to an Ethernet multicast address.
123  * The high-order 16 bits of the Ethernet address are statically assigned,
124  * and the low-order 32 bits are taken from the low end of the IP6 address.
125  */
126 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
127 	/* struct in6_addr *ip6addr; */					\
128 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
129 {                                                                       \
130 	(enaddr)[0] = 0x33;						\
131 	(enaddr)[1] = 0x33;						\
132 	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
133 	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
134 	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
135 	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
136 }
137 #endif
138 
139 /*
140  * Structure shared between the ethernet driver modules and
141  * the multicast list code.  For example, each ec_softc or il_softc
142  * begins with this structure.
143  */
144 struct	ethercom {
145 	struct	 ifnet ec_if;			/* network-visible interface */
146 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
147 						   addrs */
148 	int	 ec_multicnt;			/* length of ec_multiaddrs
149 						   list */
150 	int	 ec_capabilities;		/* capabilities, provided by
151 						   driver */
152 	int	 ec_capenable;			/* tells hardware which
153 						   capabilities to enable */
154 
155 	int	 ec_nvlans;			/* # VLANs on this interface */
156 };
157 
158 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
159 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
160 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
161 
162 #ifdef	_KERNEL
163 extern u_int8_t etherbroadcastaddr[ETHER_ADDR_LEN];
164 extern u_int8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
165 extern u_int8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
166 
167 int	ether_ioctl(struct ifnet *, u_long, caddr_t);
168 int	ether_addmulti (struct ifreq *, struct ethercom *);
169 int	ether_delmulti (struct ifreq *, struct ethercom *);
170 int	ether_changeaddr (struct ifreq *, struct ethercom *);
171 int	ether_multiaddr(struct sockaddr *, u_int8_t[], u_int8_t[]);
172 #endif /* _KERNEL */
173 
174 /*
175  * Ethernet multicast address structure.  There is one of these for each
176  * multicast address or range of multicast addresses that we are supposed
177  * to listen to on a particular interface.  They are kept in a linked list,
178  * rooted in the interface's ethercom structure.
179  */
180 struct ether_multi {
181 	u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
182 	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
183 	struct	 ethercom *enm_ec;	/* back pointer to ethercom */
184 	u_int	 enm_refcount;		/* no. claims to this addr/range */
185 	LIST_ENTRY(ether_multi) enm_list;
186 };
187 
188 /*
189  * Structure used by macros below to remember position when stepping through
190  * all of the ether_multi records.
191  */
192 struct ether_multistep {
193 	struct ether_multi  *e_enm;
194 };
195 
196 /*
197  * Macro for looking up the ether_multi record for a given range of Ethernet
198  * multicast addresses connected to a given ethercom structure.  If no matching
199  * record is found, "enm" returns NULL.
200  */
201 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
202 	/* u_int8_t addrlo[ETHER_ADDR_LEN]; */				\
203 	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
204 	/* struct ethercom *ec; */					\
205 	/* struct ether_multi *enm; */					\
206 {									\
207 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
208 	    (enm) != NULL &&						\
209 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
210 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
211 		(enm) = LIST_NEXT((enm), enm_list));			\
212 }
213 
214 /*
215  * Macro to step through all of the ether_multi records, one at a time.
216  * The current position is remembered in "step", which the caller must
217  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
218  * and get the first record.  Both macros return a NULL "enm" when there
219  * are no remaining records.
220  */
221 #define ETHER_NEXT_MULTI(step, enm) \
222 	/* struct ether_multistep step; */  \
223 	/* struct ether_multi *enm; */  \
224 { \
225 	if (((enm) = (step).e_enm) != NULL) \
226 		(step).e_enm = LIST_NEXT((enm), enm_list); \
227 }
228 
229 #define ETHER_FIRST_MULTI(step, ec, enm) \
230 	/* struct ether_multistep step; */ \
231 	/* struct ethercom *ec; */ \
232 	/* struct ether_multi *enm; */ \
233 { \
234 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
235 	ETHER_NEXT_MULTI((step), (enm)); \
236 }
237 
238 #ifdef _KERNEL
239 void	ether_ifattach(struct ifnet *, const u_int8_t *);
240 void	ether_ifdetach(struct ifnet *);
241 
242 char	*ether_sprintf(const u_int8_t *);
243 
244 u_int32_t ether_crc32_le(const u_int8_t *, size_t);
245 u_int32_t ether_crc32_be(const u_int8_t *, size_t);
246 
247 #else
248 /*
249  * Prototype ethers(3) functions.
250  */
251 #include <sys/cdefs.h>
252 __BEGIN_DECLS
253 char *	ether_ntoa __P((struct ether_addr *));
254 struct ether_addr *
255 	ether_aton __P((const char *));
256 int	ether_ntohost __P((char *, struct ether_addr *));
257 int	ether_hostton __P((const char *, struct ether_addr *));
258 int	ether_line __P((const char *, struct ether_addr *, char *));
259 __END_DECLS
260 #endif
261 
262 #endif /* _STANDALONE */
263 
264 #endif /* _NET_IF_ETHER_H_ */
265