xref: /netbsd-src/sys/net/if_ether.h (revision b78992537496bc71ee3d761f9fe0be0fc0a9a001)
1 /*	$NetBSD: if_ether.h,v 1.53 2008/07/25 20:04:50 dsl 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 #define	ETHER_PPPOE_ENCAP_LEN 8	/* length of PPPoE encapsulation */
60 
61 /*
62  * Ethernet address - 6 octets
63  * this is only used by the ethers(3) functions.
64  */
65 struct ether_addr {
66 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
67 } __packed;
68 
69 /*
70  * Structure of a 10Mb/s Ethernet header.
71  */
72 struct ether_header {
73 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
74 	uint8_t  ether_shost[ETHER_ADDR_LEN];
75 	uint16_t ether_type;
76 } __packed;
77 
78 #include <net/ethertypes.h>
79 
80 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
81 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
82 
83 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
84 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
85 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
86 
87 /*
88  * Compute the maximum frame size based on ethertype (i.e. possible
89  * encapsulation) and whether or not an FCS is present.
90  */
91 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
92 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
93 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
94 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
95 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
96 
97 /*
98  * Ethernet CRC32 polynomials (big- and little-endian verions).
99  */
100 #define	ETHER_CRC_POLY_LE	0xedb88320
101 #define	ETHER_CRC_POLY_BE	0x04c11db6
102 
103 #ifndef _STANDALONE
104 
105 /*
106  * Ethernet-specific mbuf flags.
107  */
108 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
109 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
110 
111 #ifdef _KERNEL
112 /*
113  * Macro to map an IP multicast address to an Ethernet multicast address.
114  * The high-order 25 bits of the Ethernet address are statically assigned,
115  * and the low-order 23 bits are taken from the low end of the IP address.
116  */
117 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
118 	/* const struct in_addr *ipaddr; */				\
119 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
120 do {									\
121 	(enaddr)[0] = 0x01;						\
122 	(enaddr)[1] = 0x00;						\
123 	(enaddr)[2] = 0x5e;						\
124 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
125 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
126 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
127 } while (/*CONSTCOND*/0)
128 /*
129  * Macro to map an IP6 multicast address to an Ethernet multicast address.
130  * The high-order 16 bits of the Ethernet address are statically assigned,
131  * and the low-order 32 bits are taken from the low end of the IP6 address.
132  */
133 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
134 	/* struct in6_addr *ip6addr; */					\
135 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
136 {                                                                       \
137 	(enaddr)[0] = 0x33;						\
138 	(enaddr)[1] = 0x33;						\
139 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
140 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
141 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
142 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
143 }
144 #endif
145 
146 struct mii_data;
147 
148 /*
149  * Structure shared between the ethernet driver modules and
150  * the multicast list code.  For example, each ec_softc or il_softc
151  * begins with this structure.
152  */
153 struct ethercom {
154 	struct	ifnet ec_if;			/* network-visible interface */
155 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
156 						   addrs */
157 	int	ec_multicnt;			/* length of ec_multiaddrs
158 						   list */
159 	int	ec_capabilities;		/* capabilities, provided by
160 						   driver */
161 	int	ec_capenable;			/* tells hardware which
162 						   capabilities to enable */
163 
164 	int	ec_nvlans;			/* # VLANs on this interface */
165 	/* The device handle for the MII bus child device. */
166 	struct mii_data				*ec_mii;
167 #ifdef MBUFTRACE
168 	struct	mowner ec_rx_mowner;		/* mbufs received */
169 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
170 #endif
171 };
172 
173 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
174 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
175 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
176 
177 #ifdef	_KERNEL
178 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
179 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
180 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
181 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
182 
183 int	ether_ioctl(struct ifnet *, u_long, void *);
184 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
185 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
186 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
187 #endif /* _KERNEL */
188 
189 /*
190  * Ethernet multicast address structure.  There is one of these for each
191  * multicast address or range of multicast addresses that we are supposed
192  * to listen to on a particular interface.  They are kept in a linked list,
193  * rooted in the interface's ethercom structure.
194  */
195 struct ether_multi {
196 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
197 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
198 	u_int	 enm_refcount;		/* no. claims to this addr/range */
199 	LIST_ENTRY(ether_multi) enm_list;
200 };
201 
202 /*
203  * Structure used by macros below to remember position when stepping through
204  * all of the ether_multi records.
205  */
206 struct ether_multistep {
207 	struct ether_multi  *e_enm;
208 };
209 
210 /*
211  * Macro for looking up the ether_multi record for a given range of Ethernet
212  * multicast addresses connected to a given ethercom structure.  If no matching
213  * record is found, "enm" returns NULL.
214  */
215 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
216 	/* uint8_t addrlo[ETHER_ADDR_LEN]; */				\
217 	/* uint8_t addrhi[ETHER_ADDR_LEN]; */				\
218 	/* struct ethercom *ec; */					\
219 	/* struct ether_multi *enm; */					\
220 {									\
221 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
222 	    (enm) != NULL &&						\
223 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
224 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
225 		(enm) = LIST_NEXT((enm), enm_list));			\
226 }
227 
228 /*
229  * Macro to step through all of the ether_multi records, one at a time.
230  * The current position is remembered in "step", which the caller must
231  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
232  * and get the first record.  Both macros return a NULL "enm" when there
233  * are no remaining records.
234  */
235 #define ETHER_NEXT_MULTI(step, enm) \
236 	/* struct ether_multistep step; */  \
237 	/* struct ether_multi *enm; */  \
238 { \
239 	if (((enm) = (step).e_enm) != NULL) \
240 		(step).e_enm = LIST_NEXT((enm), enm_list); \
241 }
242 
243 #define ETHER_FIRST_MULTI(step, ec, enm) \
244 	/* struct ether_multistep step; */ \
245 	/* struct ethercom *ec; */ \
246 	/* struct ether_multi *enm; */ \
247 { \
248 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
249 	ETHER_NEXT_MULTI((step), (enm)); \
250 }
251 
252 #ifdef _KERNEL
253 
254 /*
255  * Ethernet 802.1Q VLAN structures.
256  */
257 
258 /* add VLAN tag to input/received packet */
259 static inline int vlan_input_tag(struct ifnet *, struct mbuf *, u_int);
260 static inline int
261 vlan_input_tag(struct ifnet *ifp, struct mbuf *m, u_int vlanid)
262 {
263 	struct m_tag *mtag;
264 	mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int), M_NOWAIT);
265 	if (mtag == NULL) {
266 		ifp->if_ierrors++;
267 		printf("%s: unable to allocate VLAN tag\n", ifp->if_xname);
268 		m_freem(m);
269 		return 1;
270 	}
271 	*(u_int *)(mtag + 1) = vlanid;
272 	m_tag_prepend(m, mtag);
273 	return 0;
274 }
275 
276 #define VLAN_INPUT_TAG(ifp, m, vlanid, _errcase)		\
277     if (vlan_input_tag(ifp, m, vlanid) != 0) {	 		\
278 	_errcase;						\
279     }
280 
281 /* extract VLAN tag from output/trasmit packet */
282 #define VLAN_OUTPUT_TAG(ec, m0)			\
283 	(VLAN_ATTACHED(ec) ? m_tag_find((m0), PACKET_TAG_VLAN, NULL) : NULL)
284 
285 /* extract VLAN ID value from a VLAN tag */
286 #define VLAN_TAG_VALUE(mtag)	\
287 	((*(u_int *)(mtag + 1)) & 4095)
288 
289 /* test if any VLAN is configured for this interface */
290 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
291 
292 void	ether_ifattach(struct ifnet *, const uint8_t *);
293 void	ether_ifdetach(struct ifnet *);
294 int	ether_mediachange(struct ifnet *);
295 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
296 
297 char	*ether_sprintf(const uint8_t *);
298 char	*ether_snprintf(char *, size_t, const uint8_t *);
299 
300 uint32_t ether_crc32_le(const uint8_t *, size_t);
301 uint32_t ether_crc32_be(const uint8_t *, size_t);
302 
303 int	ether_nonstatic_aton(u_char *, char *);
304 #else
305 /*
306  * Prototype ethers(3) functions.
307  */
308 #include <sys/cdefs.h>
309 __BEGIN_DECLS
310 char *	ether_ntoa __P((const struct ether_addr *));
311 struct ether_addr *
312 	ether_aton __P((const char *));
313 int	ether_ntohost __P((char *, const struct ether_addr *));
314 int	ether_hostton __P((const char *, struct ether_addr *));
315 int	ether_line __P((const char *, struct ether_addr *, char *));
316 __END_DECLS
317 #endif
318 
319 #endif /* _STANDALONE */
320 
321 #endif /* !_NET_IF_ETHER_H_ */
322