xref: /netbsd-src/sys/net/if_ether.h (revision deb6f0161a9109e7de9b519dc8dfb9478668dcdd)
1 /*	$NetBSD: if_ether.h,v 1.75 2018/06/14 08:00:24 yamaguchi 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 #ifndef _STANDALONE
45 #include <net/if.h>
46 #endif
47 
48 /*
49  * Some basic Ethernet constants.
50  */
51 #define	ETHER_ADDR_LEN	6	/* length of an Ethernet address */
52 #define	ETHER_TYPE_LEN	2	/* length of the Ethernet type field */
53 #define	ETHER_CRC_LEN	4	/* length of the Ethernet CRC */
54 #define	ETHER_HDR_LEN	((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)
55 #define	ETHER_MIN_LEN	64	/* minimum frame length, including CRC */
56 #define	ETHER_MAX_LEN	1518	/* maximum frame length, including CRC */
57 #define	ETHER_MAX_LEN_JUMBO 9018 /* maximum jumbo frame len, including CRC */
58 
59 /*
60  * Some Ethernet extensions.
61  */
62 #define	ETHER_VLAN_ENCAP_LEN	4      /* length of 802.1Q VLAN encapsulation */
63 #define	EVL_VLANOFTAG(tag)	((tag) & 4095)		/* VLAN ID */
64 #define	EVL_PRIOFTAG(tag)	(((tag) >> 13) & 7)	/* Priority */
65 #define	EVL_CFIOFTAG(tag)	(((tag) >> 12) & 1)	/* CFI */
66 #define	ETHER_PPPOE_ENCAP_LEN	8	/* length of PPPoE encapsulation */
67 
68 /*
69  * Ethernet address - 6 octets
70  * this is only used by the ethers(3) functions.
71  */
72 struct ether_addr {
73 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
74 } __packed;
75 
76 /*
77  * Structure of a 10Mb/s Ethernet header.
78  */
79 struct ether_header {
80 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
81 	uint8_t  ether_shost[ETHER_ADDR_LEN];
82 	uint16_t ether_type;
83 } __packed;
84 
85 #include <net/ethertypes.h>
86 
87 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
88 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
89 
90 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
91 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
92 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
93 
94 /*
95  * Compute the maximum frame size based on ethertype (i.e. possible
96  * encapsulation) and whether or not an FCS is present.
97  */
98 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
99 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
100 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
101 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
102 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
103 
104 /*
105  * Ethernet CRC32 polynomials (big- and little-endian verions).
106  */
107 #define	ETHER_CRC_POLY_LE	0xedb88320
108 #define	ETHER_CRC_POLY_BE	0x04c11db6
109 
110 #ifndef _STANDALONE
111 
112 /*
113  * Ethernet-specific mbuf flags.
114  */
115 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
116 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
117 
118 #ifdef _KERNEL
119 /*
120  * Macro to map an IP multicast address to an Ethernet multicast address.
121  * The high-order 25 bits of the Ethernet address are statically assigned,
122  * and the low-order 23 bits are taken from the low end of the IP address.
123  */
124 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
125 	/* const struct in_addr *ipaddr; */				\
126 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
127 do {									\
128 	(enaddr)[0] = 0x01;						\
129 	(enaddr)[1] = 0x00;						\
130 	(enaddr)[2] = 0x5e;						\
131 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
132 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
133 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
134 } while (/*CONSTCOND*/0)
135 /*
136  * Macro to map an IP6 multicast address to an Ethernet multicast address.
137  * The high-order 16 bits of the Ethernet address are statically assigned,
138  * and the low-order 32 bits are taken from the low end of the IP6 address.
139  */
140 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
141 	/* struct in6_addr *ip6addr; */					\
142 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
143 {                                                                       \
144 	(enaddr)[0] = 0x33;						\
145 	(enaddr)[1] = 0x33;						\
146 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
147 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
148 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
149 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
150 }
151 #endif
152 
153 struct mii_data;
154 
155 struct ethercom;
156 
157 typedef int (*ether_cb_t)(struct ethercom *);
158 
159 /*
160  * Structure shared between the ethernet driver modules and
161  * the multicast list code.  For example, each ec_softc or il_softc
162  * begins with this structure.
163  */
164 struct ethercom {
165 	struct	ifnet ec_if;			/* network-visible interface */
166 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
167 						   addrs */
168 	int	ec_multicnt;			/* length of ec_multiaddrs
169 						   list */
170 	int	ec_capabilities;		/* capabilities, provided by
171 						   driver */
172 	int	ec_capenable;			/* tells hardware which
173 						   capabilities to enable */
174 
175 	int	ec_nvlans;			/* # VLANs on this interface */
176 	/* The device handle for the MII bus child device. */
177 	struct mii_data				*ec_mii;
178 	/* Called after a change to ec_if.if_flags.  Returns
179 	 * ENETRESET if the device should be reinitialized with
180 	 * ec_if.if_init, 0 on success, not 0 on failure.
181 	 */
182 	ether_cb_t				ec_ifflags_cb;
183 	kmutex_t				*ec_lock;
184 #ifdef MBUFTRACE
185 	struct	mowner ec_rx_mowner;		/* mbufs received */
186 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
187 #endif
188 };
189 
190 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
191 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
192 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
193 #define	ETHERCAP_MASK		0x00000007
194 
195 #define	ECCAPBITS		\
196 	"\020"			\
197 	"\1VLAN_MTU"		\
198 	"\2VLAN_HWTAGGING"	\
199 	"\3JUMBO_MTU"
200 
201 /* ioctl() for Ethernet capabilities */
202 struct eccapreq {
203 	char		eccr_name[IFNAMSIZ];	/* if name, e.g. "en0" */
204 	int		eccr_capabilities;	/* supported capabiliites */
205 	int		eccr_capenable;		/* capabilities enabled */
206 };
207 
208 /* sysctl for Ethernet multicast addresses */
209 struct ether_multi_sysctl {
210 	u_int   enm_refcount;
211 	uint8_t enm_addrlo[ETHER_ADDR_LEN];
212 	uint8_t enm_addrhi[ETHER_ADDR_LEN];
213 };
214 
215 #ifdef	_KERNEL
216 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
217 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
218 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
219 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
220 
221 void	ether_set_ifflags_cb(struct ethercom *, ether_cb_t);
222 int	ether_ioctl(struct ifnet *, u_long, void *);
223 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
224 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
225 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
226 void    ether_input(struct ifnet *, struct mbuf *);
227 
228 /*
229  * Ethernet multicast address structure.  There is one of these for each
230  * multicast address or range of multicast addresses that we are supposed
231  * to listen to on a particular interface.  They are kept in a linked list,
232  * rooted in the interface's ethercom structure.
233  */
234 struct ether_multi {
235 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
236 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
237 	u_int	 enm_refcount;		/* no. claims to this addr/range */
238 	LIST_ENTRY(ether_multi) enm_list;
239 };
240 
241 /*
242  * Structure used by macros below to remember position when stepping through
243  * all of the ether_multi records.
244  */
245 struct ether_multistep {
246 	struct ether_multi  *e_enm;
247 };
248 
249 /*
250  * lookup the ether_multi record for a given range of Ethernet
251  * multicast addresses connected to a given ethercom structure.
252  * If no matching record is found, NULL is returned.
253  */
254 static __inline struct ether_multi *
255 ether_lookup_multi(const uint8_t *addrlo, const uint8_t *addrhi,
256     const struct ethercom *ec)
257 {
258 	struct ether_multi *enm;
259 
260 	LIST_FOREACH(enm, &ec->ec_multiaddrs, enm_list) {
261 		if (memcmp(enm->enm_addrlo, addrlo, ETHER_ADDR_LEN) != 0)
262 			continue;
263 		if (memcmp(enm->enm_addrhi, addrhi, ETHER_ADDR_LEN) != 0)
264 			continue;
265 
266 		break;
267 	}
268 
269 	return enm;
270 }
271 
272 /*
273  * step through all of the ether_multi records, one at a time.
274  * The current position is remembered in "step", which the caller must
275  * provide.  ether_first_multi(), below, must be called to initialize "step"
276  * and get the first record.  Both functions return a NULL when there
277  * are no remaining records.
278  */
279 static __inline struct ether_multi *
280 ether_next_multi(struct ether_multistep *step)
281 {
282 	struct ether_multi *enm;
283 
284 	enm = step->e_enm;
285 	if (enm != NULL)
286 		step->e_enm = LIST_NEXT(enm, enm_list);
287 
288 	return enm;
289 }
290 #define ETHER_NEXT_MULTI(step, enm) \
291 	/* struct ether_multistep step; */  \
292 	/* struct ether_multi *enm; */  \
293 	(enm) = ether_next_multi(&(step))
294 
295 static __inline struct ether_multi *
296 ether_first_multi(struct ether_multistep *step, const struct ethercom *ec)
297 {
298 
299 	step->e_enm = LIST_FIRST(&ec->ec_multiaddrs);
300 
301 	return ether_next_multi(step);
302 }
303 
304 #define ETHER_FIRST_MULTI(step, ec, enm) \
305 	/* struct ether_multistep step; */ \
306 	/* struct ethercom *ec; */ \
307 	/* struct ether_multi *enm; */ \
308 	(enm) = ether_first_multi(&(step), (ec))
309 
310 #define ETHER_LOCK(ec)		mutex_enter((ec)->ec_lock)
311 #define ETHER_UNLOCK(ec)	mutex_exit((ec)->ec_lock)
312 
313 /*
314  * Ethernet 802.1Q VLAN structures.
315  */
316 
317 /* add VLAN tag to input/received packet */
318 static __inline void
319 vlan_set_tag(struct mbuf *m, uint16_t vlantag)
320 {
321 	/* VLAN tag contains priority, CFI and VLAN ID */
322 	KASSERT((m->m_flags & M_PKTHDR) != 0);
323 	m->m_pkthdr.ether_vtag = vlantag;
324 	m->m_flags |= M_VLANTAG;
325 	return;
326 }
327 
328 static __inline bool
329 vlan_has_tag(struct mbuf *m)
330 {
331 	return (m->m_flags & M_VLANTAG) != 0;
332 }
333 
334 /* extract VLAN ID value from a VLAN tag */
335 static __inline uint16_t
336 vlan_get_tag(struct mbuf *m)
337 {
338 	KASSERT((m->m_flags & M_PKTHDR) != 0);
339 	KASSERT(m->m_flags & M_VLANTAG);
340 	return m->m_pkthdr.ether_vtag;
341 }
342 
343 /* test if any VLAN is configured for this interface */
344 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
345 
346 void	etherinit(void);
347 void	ether_ifattach(struct ifnet *, const uint8_t *);
348 void	ether_ifdetach(struct ifnet *);
349 int	ether_mediachange(struct ifnet *);
350 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
351 
352 char	*ether_sprintf(const uint8_t *);
353 char	*ether_snprintf(char *, size_t, const uint8_t *);
354 
355 uint32_t ether_crc32_le(const uint8_t *, size_t);
356 uint32_t ether_crc32_be(const uint8_t *, size_t);
357 
358 int	ether_aton_r(u_char *, size_t, const char *);
359 int	ether_enable_vlan_mtu(struct ifnet *);
360 int	ether_disable_vlan_mtu(struct ifnet *);
361 #else
362 /*
363  * Prototype ethers(3) functions.
364  */
365 #include <sys/cdefs.h>
366 __BEGIN_DECLS
367 char *	ether_ntoa(const struct ether_addr *);
368 struct ether_addr *
369 	ether_aton(const char *);
370 int	ether_ntohost(char *, const struct ether_addr *);
371 int	ether_hostton(const char *, struct ether_addr *);
372 int	ether_line(const char *, struct ether_addr *, char *);
373 __END_DECLS
374 #endif
375 
376 #endif /* _STANDALONE */
377 
378 #endif /* !_NET_IF_ETHER_H_ */
379