xref: /netbsd-src/sys/net/if_ether.h (revision 1580a27b92f58fcdcb23fdfbc04a7c2b54a0b7c8)
1 /*	$NetBSD: if_ether.h,v 1.68 2017/09/28 16:26:14 christos 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	ETHER_VLAN_MASK	0xFFF	/* bits in a vlan tag */
64 #define	ETHER_PPPOE_ENCAP_LEN 8	/* length of PPPoE encapsulation */
65 
66 /*
67  * Ethernet address - 6 octets
68  * this is only used by the ethers(3) functions.
69  */
70 struct ether_addr {
71 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
72 } __packed;
73 
74 /*
75  * Structure of a 10Mb/s Ethernet header.
76  */
77 struct ether_header {
78 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
79 	uint8_t  ether_shost[ETHER_ADDR_LEN];
80 	uint16_t ether_type;
81 } __packed;
82 
83 #include <net/ethertypes.h>
84 
85 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
86 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
87 
88 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
89 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
90 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
91 
92 /*
93  * Compute the maximum frame size based on ethertype (i.e. possible
94  * encapsulation) and whether or not an FCS is present.
95  */
96 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
97 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
98 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
99 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
100 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
101 
102 /*
103  * Ethernet CRC32 polynomials (big- and little-endian verions).
104  */
105 #define	ETHER_CRC_POLY_LE	0xedb88320
106 #define	ETHER_CRC_POLY_BE	0x04c11db6
107 
108 #ifndef _STANDALONE
109 
110 /*
111  * Ethernet-specific mbuf flags.
112  */
113 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
114 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
115 
116 #ifdef _KERNEL
117 /*
118  * Macro to map an IP multicast address to an Ethernet multicast address.
119  * The high-order 25 bits of the Ethernet address are statically assigned,
120  * and the low-order 23 bits are taken from the low end of the IP address.
121  */
122 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
123 	/* const struct in_addr *ipaddr; */				\
124 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
125 do {									\
126 	(enaddr)[0] = 0x01;						\
127 	(enaddr)[1] = 0x00;						\
128 	(enaddr)[2] = 0x5e;						\
129 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
130 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
131 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
132 } while (/*CONSTCOND*/0)
133 /*
134  * Macro to map an IP6 multicast address to an Ethernet multicast address.
135  * The high-order 16 bits of the Ethernet address are statically assigned,
136  * and the low-order 32 bits are taken from the low end of the IP6 address.
137  */
138 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
139 	/* struct in6_addr *ip6addr; */					\
140 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
141 {                                                                       \
142 	(enaddr)[0] = 0x33;						\
143 	(enaddr)[1] = 0x33;						\
144 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
145 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
146 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
147 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
148 }
149 #endif
150 
151 struct mii_data;
152 
153 struct ethercom;
154 
155 typedef int (*ether_cb_t)(struct ethercom *);
156 
157 /*
158  * Structure shared between the ethernet driver modules and
159  * the multicast list code.  For example, each ec_softc or il_softc
160  * begins with this structure.
161  */
162 struct ethercom {
163 	struct	ifnet ec_if;			/* network-visible interface */
164 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
165 						   addrs */
166 	int	ec_multicnt;			/* length of ec_multiaddrs
167 						   list */
168 	int	ec_capabilities;		/* capabilities, provided by
169 						   driver */
170 	int	ec_capenable;			/* tells hardware which
171 						   capabilities to enable */
172 
173 	int	ec_nvlans;			/* # VLANs on this interface */
174 	/* The device handle for the MII bus child device. */
175 	struct mii_data				*ec_mii;
176 	/* Called after a change to ec_if.if_flags.  Returns
177 	 * ENETRESET if the device should be reinitialized with
178 	 * ec_if.if_init, 0 on success, not 0 on failure.
179 	 */
180 	ether_cb_t				ec_ifflags_cb;
181 	kmutex_t				*ec_lock;
182 #ifdef MBUFTRACE
183 	struct	mowner ec_rx_mowner;		/* mbufs received */
184 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
185 #endif
186 };
187 
188 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
189 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
190 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
191 #define	ETHERCAP_MASK		0x00000007
192 
193 #define	ECCAPBITS		\
194 	"\020"			\
195 	"\1VLAN_MTU"		\
196 	"\2VLAN_HWTAGGING"	\
197 	"\3JUMBO_MTU"
198 
199 /* ioctl() for Ethernet capabilities */
200 struct eccapreq {
201 	char		eccr_name[IFNAMSIZ];	/* if name, e.g. "en0" */
202 	int		eccr_capabilities;	/* supported capabiliites */
203 	int		eccr_capenable;		/* capabilities enabled */
204 };
205 
206 #ifdef	_KERNEL
207 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
208 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
209 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
210 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
211 
212 void	ether_set_ifflags_cb(struct ethercom *, ether_cb_t);
213 int	ether_ioctl(struct ifnet *, u_long, void *);
214 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
215 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
216 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
217 void    ether_input(struct ifnet *, struct mbuf *);
218 #endif /* _KERNEL */
219 
220 /*
221  * Ethernet multicast address structure.  There is one of these for each
222  * multicast address or range of multicast addresses that we are supposed
223  * to listen to on a particular interface.  They are kept in a linked list,
224  * rooted in the interface's ethercom structure.
225  */
226 struct ether_multi {
227 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
228 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
229 	u_int	 enm_refcount;		/* no. claims to this addr/range */
230 	LIST_ENTRY(ether_multi) enm_list;
231 };
232 
233 struct ether_multi_sysctl {
234 	u_int   enm_refcount;
235 	uint8_t enm_addrlo[ETHER_ADDR_LEN];
236 	uint8_t enm_addrhi[ETHER_ADDR_LEN];
237 };
238 
239 /*
240  * Structure used by macros below to remember position when stepping through
241  * all of the ether_multi records.
242  */
243 struct ether_multistep {
244 	struct ether_multi  *e_enm;
245 };
246 
247 /*
248  * Macro for looking up the ether_multi record for a given range of Ethernet
249  * multicast addresses connected to a given ethercom structure.  If no matching
250  * record is found, "enm" returns NULL.
251  */
252 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
253 	/* uint8_t addrlo[ETHER_ADDR_LEN]; */				\
254 	/* uint8_t addrhi[ETHER_ADDR_LEN]; */				\
255 	/* struct ethercom *ec; */					\
256 	/* struct ether_multi *enm; */					\
257 {									\
258 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
259 	    (enm) != NULL &&						\
260 	    (memcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
261 	     memcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
262 		(enm) = LIST_NEXT((enm), enm_list));			\
263 }
264 
265 /*
266  * Macro to step through all of the ether_multi records, one at a time.
267  * The current position is remembered in "step", which the caller must
268  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
269  * and get the first record.  Both macros return a NULL "enm" when there
270  * are no remaining records.
271  */
272 #define ETHER_NEXT_MULTI(step, enm) \
273 	/* struct ether_multistep step; */  \
274 	/* struct ether_multi *enm; */  \
275 { \
276 	if (((enm) = (step).e_enm) != NULL) \
277 		(step).e_enm = LIST_NEXT((enm), enm_list); \
278 }
279 
280 #define ETHER_FIRST_MULTI(step, ec, enm) \
281 	/* struct ether_multistep step; */ \
282 	/* struct ethercom *ec; */ \
283 	/* struct ether_multi *enm; */ \
284 { \
285 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
286 	ETHER_NEXT_MULTI((step), (enm)); \
287 }
288 
289 #ifdef _KERNEL
290 
291 #define ETHER_LOCK(ec)		mutex_enter((ec)->ec_lock)
292 #define ETHER_UNLOCK(ec)	mutex_exit((ec)->ec_lock)
293 
294 /*
295  * Ethernet 802.1Q VLAN structures.
296  */
297 
298 /* add VLAN tag to input/received packet */
299 static inline void
300 vlan_set_tag(struct mbuf *m, u_int16_t vlanid)
301 {
302 
303 	KASSERT((vlanid & ~ETHER_VLAN_MASK) == 0);
304 
305 	m->m_pkthdr.ether_vtag = vlanid;
306 	m->m_flags |= M_VLANTAG;
307 	return;
308 }
309 
310 static inline bool
311 vlan_has_tag(struct mbuf *m)
312 {
313 	return (m->m_flags & M_VLANTAG) != 0;
314 }
315 
316 /* extract VLAN ID value from a VLAN tag */
317 static inline uint16_t
318 vlan_get_tag(struct mbuf *m)
319 {
320 	KASSERT(m->m_flags & M_VLANTAG);
321 	return m->m_pkthdr.ether_vtag;
322 }
323 
324 /* test if any VLAN is configured for this interface */
325 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
326 
327 void	etherinit(void);
328 void	ether_ifattach(struct ifnet *, const uint8_t *);
329 void	ether_ifdetach(struct ifnet *);
330 int	ether_mediachange(struct ifnet *);
331 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
332 
333 char	*ether_sprintf(const uint8_t *);
334 char	*ether_snprintf(char *, size_t, const uint8_t *);
335 
336 uint32_t ether_crc32_le(const uint8_t *, size_t);
337 uint32_t ether_crc32_be(const uint8_t *, size_t);
338 
339 int	ether_aton_r(u_char *, size_t, const char *);
340 int	ether_enable_vlan_mtu(struct ifnet *);
341 int	ether_disable_vlan_mtu(struct ifnet *);
342 #else
343 /*
344  * Prototype ethers(3) functions.
345  */
346 #include <sys/cdefs.h>
347 __BEGIN_DECLS
348 char *	ether_ntoa(const struct ether_addr *);
349 struct ether_addr *
350 	ether_aton(const char *);
351 int	ether_ntohost(char *, const struct ether_addr *);
352 int	ether_hostton(const char *, struct ether_addr *);
353 int	ether_line(const char *, struct ether_addr *, char *);
354 __END_DECLS
355 #endif
356 
357 #endif /* _STANDALONE */
358 
359 #endif /* !_NET_IF_ETHER_H_ */
360