xref: /netbsd-src/sys/net/if_ether.h (revision 2de962bd804263c16657f586aa00f1704045df8e)
1 /*	$NetBSD: if_ether.h,v 1.51 2008/05/22 01:15:33 dyoung 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. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
32  */
33 
34 #ifndef _NET_IF_ETHER_H_
35 #define _NET_IF_ETHER_H_
36 
37 #ifdef _KERNEL
38 #ifdef _KERNEL_OPT
39 #include "opt_mbuftrace.h"
40 #endif
41 #include <sys/mbuf.h>
42 #endif
43 
44 /*
45  * Some basic Ethernet constants.
46  */
47 #define	ETHER_ADDR_LEN	6	/* length of an Ethernet address */
48 #define	ETHER_TYPE_LEN	2	/* length of the Ethernet type field */
49 #define	ETHER_CRC_LEN	4	/* length of the Ethernet CRC */
50 #define	ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
51 #define	ETHER_MIN_LEN	64	/* minimum frame length, including CRC */
52 #define	ETHER_MAX_LEN	1518	/* maximum frame length, including CRC */
53 #define	ETHER_MAX_LEN_JUMBO 9018 /* maximum jumbo frame len, including CRC */
54 
55 /*
56  * Some Ethernet extensions.
57  */
58 #define	ETHER_VLAN_ENCAP_LEN 4	/* length of 802.1Q VLAN encapsulation */
59 
60 /*
61  * Ethernet address - 6 octets
62  * this is only used by the ethers(3) functions.
63  */
64 struct ether_addr {
65 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
66 } __packed;
67 
68 /*
69  * Structure of a 10Mb/s Ethernet header.
70  */
71 struct ether_header {
72 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
73 	uint8_t  ether_shost[ETHER_ADDR_LEN];
74 	uint16_t ether_type;
75 } __packed;
76 
77 #include <net/ethertypes.h>
78 
79 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
80 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
81 
82 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
83 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
84 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
85 
86 /*
87  * Compute the maximum frame size based on ethertype (i.e. possible
88  * encapsulation) and whether or not an FCS is present.
89  */
90 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
91 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
92 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
93 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0))
94 
95 /*
96  * Ethernet CRC32 polynomials (big- and little-endian verions).
97  */
98 #define	ETHER_CRC_POLY_LE	0xedb88320
99 #define	ETHER_CRC_POLY_BE	0x04c11db6
100 
101 #ifndef _STANDALONE
102 
103 /*
104  * Ethernet-specific mbuf flags.
105  */
106 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
107 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
108 
109 #ifdef _KERNEL
110 /*
111  * Macro to map an IP multicast address to an Ethernet multicast address.
112  * The high-order 25 bits of the Ethernet address are statically assigned,
113  * and the low-order 23 bits are taken from the low end of the IP address.
114  */
115 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
116 	/* const struct in_addr *ipaddr; */				\
117 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
118 do {									\
119 	(enaddr)[0] = 0x01;						\
120 	(enaddr)[1] = 0x00;						\
121 	(enaddr)[2] = 0x5e;						\
122 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
123 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
124 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
125 } while (/*CONSTCOND*/0)
126 /*
127  * Macro to map an IP6 multicast address to an Ethernet multicast address.
128  * The high-order 16 bits of the Ethernet address are statically assigned,
129  * and the low-order 32 bits are taken from the low end of the IP6 address.
130  */
131 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
132 	/* struct in6_addr *ip6addr; */					\
133 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
134 {                                                                       \
135 	(enaddr)[0] = 0x33;						\
136 	(enaddr)[1] = 0x33;						\
137 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
138 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
139 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
140 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
141 }
142 #endif
143 
144 struct mii_data;
145 
146 /*
147  * Structure shared between the ethernet driver modules and
148  * the multicast list code.  For example, each ec_softc or il_softc
149  * begins with this structure.
150  */
151 struct ethercom {
152 	struct	ifnet ec_if;			/* network-visible interface */
153 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
154 						   addrs */
155 	int	ec_multicnt;			/* length of ec_multiaddrs
156 						   list */
157 	int	ec_capabilities;		/* capabilities, provided by
158 						   driver */
159 	int	ec_capenable;			/* tells hardware which
160 						   capabilities to enable */
161 
162 	int	ec_nvlans;			/* # VLANs on this interface */
163 	/* The device handle for the MII bus child device. */
164 	struct mii_data				*ec_mii;
165 #ifdef MBUFTRACE
166 	struct	mowner ec_rx_mowner;		/* mbufs received */
167 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
168 #endif
169 };
170 
171 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
172 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
173 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
174 
175 #ifdef	_KERNEL
176 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
177 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
178 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
179 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
180 
181 int	ether_ioctl(struct ifnet *, u_long, void *);
182 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
183 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
184 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
185 #endif /* _KERNEL */
186 
187 /*
188  * Ethernet multicast address structure.  There is one of these for each
189  * multicast address or range of multicast addresses that we are supposed
190  * to listen to on a particular interface.  They are kept in a linked list,
191  * rooted in the interface's ethercom structure.
192  */
193 struct ether_multi {
194 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
195 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
196 	u_int	 enm_refcount;		/* no. claims to this addr/range */
197 	LIST_ENTRY(ether_multi) enm_list;
198 };
199 
200 /*
201  * Structure used by macros below to remember position when stepping through
202  * all of the ether_multi records.
203  */
204 struct ether_multistep {
205 	struct ether_multi  *e_enm;
206 };
207 
208 /*
209  * Macro for looking up the ether_multi record for a given range of Ethernet
210  * multicast addresses connected to a given ethercom structure.  If no matching
211  * record is found, "enm" returns NULL.
212  */
213 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
214 	/* uint8_t addrlo[ETHER_ADDR_LEN]; */				\
215 	/* uint8_t addrhi[ETHER_ADDR_LEN]; */				\
216 	/* struct ethercom *ec; */					\
217 	/* struct ether_multi *enm; */					\
218 {									\
219 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
220 	    (enm) != NULL &&						\
221 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
222 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
223 		(enm) = LIST_NEXT((enm), enm_list));			\
224 }
225 
226 /*
227  * Macro to step through all of the ether_multi records, one at a time.
228  * The current position is remembered in "step", which the caller must
229  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
230  * and get the first record.  Both macros return a NULL "enm" when there
231  * are no remaining records.
232  */
233 #define ETHER_NEXT_MULTI(step, enm) \
234 	/* struct ether_multistep step; */  \
235 	/* struct ether_multi *enm; */  \
236 { \
237 	if (((enm) = (step).e_enm) != NULL) \
238 		(step).e_enm = LIST_NEXT((enm), enm_list); \
239 }
240 
241 #define ETHER_FIRST_MULTI(step, ec, enm) \
242 	/* struct ether_multistep step; */ \
243 	/* struct ethercom *ec; */ \
244 	/* struct ether_multi *enm; */ \
245 { \
246 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
247 	ETHER_NEXT_MULTI((step), (enm)); \
248 }
249 
250 #ifdef _KERNEL
251 
252 /*
253  * Ethernet 802.1Q VLAN structures.
254  */
255 
256 /* add VLAN tag to input/received packet */
257 #define	VLAN_INPUT_TAG(ifp, m, vlanid, _errcase)	\
258 	do {								\
259                 struct m_tag *mtag =					\
260                     m_tag_get(PACKET_TAG_VLAN, sizeof(u_int), M_NOWAIT);\
261                 if (mtag == NULL) {					\
262 			ifp->if_ierrors++;				\
263                         printf("%s: unable to allocate VLAN tag\n",	\
264                             ifp->if_xname);				\
265                         m_freem(m);					\
266                         _errcase;					\
267                 }							\
268                 *(u_int *)(mtag + 1) = vlanid;				\
269                 m_tag_prepend(m, mtag);					\
270 	} while(0)
271 
272 /* extract VLAN tag from output/trasmit packet */
273 #define VLAN_OUTPUT_TAG(ec, m0)			\
274 	VLAN_ATTACHED(ec) ? m_tag_find((m0), PACKET_TAG_VLAN, NULL) : NULL
275 
276 /* extract VLAN ID value from a VLAN tag */
277 #define VLAN_TAG_VALUE(mtag)	\
278 	((*(u_int *)(mtag + 1)) & 4095)
279 
280 /* test if any VLAN is configured for this interface */
281 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
282 
283 void	ether_ifattach(struct ifnet *, const uint8_t *);
284 void	ether_ifdetach(struct ifnet *);
285 int	ether_mediachange(struct ifnet *);
286 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
287 
288 char	*ether_sprintf(const uint8_t *);
289 char	*ether_snprintf(char *, size_t, const uint8_t *);
290 
291 uint32_t ether_crc32_le(const uint8_t *, size_t);
292 uint32_t ether_crc32_be(const uint8_t *, size_t);
293 
294 int	ether_nonstatic_aton(u_char *, char *);
295 #else
296 /*
297  * Prototype ethers(3) functions.
298  */
299 #include <sys/cdefs.h>
300 __BEGIN_DECLS
301 char *	ether_ntoa __P((const struct ether_addr *));
302 struct ether_addr *
303 	ether_aton __P((const char *));
304 int	ether_ntohost __P((char *, const struct ether_addr *));
305 int	ether_hostton __P((const char *, struct ether_addr *));
306 int	ether_line __P((const char *, struct ether_addr *, char *));
307 __END_DECLS
308 #endif
309 
310 #endif /* _STANDALONE */
311 
312 #endif /* !_NET_IF_ETHER_H_ */
313