xref: /netbsd-src/sys/net/if_ether.h (revision e89934bbf778a6d6d6894877c4da59d0c7835b0f)
1 /*	$NetBSD: if_ether.h,v 1.66 2016/12/28 07:32:16 ozaki-r 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_PPPOE_ENCAP_LEN 8	/* length of PPPoE encapsulation */
64 
65 /*
66  * Ethernet address - 6 octets
67  * this is only used by the ethers(3) functions.
68  */
69 struct ether_addr {
70 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
71 } __packed;
72 
73 /*
74  * Structure of a 10Mb/s Ethernet header.
75  */
76 struct ether_header {
77 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
78 	uint8_t  ether_shost[ETHER_ADDR_LEN];
79 	uint16_t ether_type;
80 } __packed;
81 
82 #include <net/ethertypes.h>
83 
84 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
85 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
86 
87 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
88 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
89 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
90 
91 /*
92  * Compute the maximum frame size based on ethertype (i.e. possible
93  * encapsulation) and whether or not an FCS is present.
94  */
95 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
96 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
97 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
98 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
99 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
100 
101 /*
102  * Ethernet CRC32 polynomials (big- and little-endian verions).
103  */
104 #define	ETHER_CRC_POLY_LE	0xedb88320
105 #define	ETHER_CRC_POLY_BE	0x04c11db6
106 
107 #ifndef _STANDALONE
108 
109 /*
110  * Ethernet-specific mbuf flags.
111  */
112 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
113 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
114 
115 #ifdef _KERNEL
116 /*
117  * Macro to map an IP multicast address to an Ethernet multicast address.
118  * The high-order 25 bits of the Ethernet address are statically assigned,
119  * and the low-order 23 bits are taken from the low end of the IP address.
120  */
121 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
122 	/* const struct in_addr *ipaddr; */				\
123 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
124 do {									\
125 	(enaddr)[0] = 0x01;						\
126 	(enaddr)[1] = 0x00;						\
127 	(enaddr)[2] = 0x5e;						\
128 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
129 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
130 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
131 } while (/*CONSTCOND*/0)
132 /*
133  * Macro to map an IP6 multicast address to an Ethernet multicast address.
134  * The high-order 16 bits of the Ethernet address are statically assigned,
135  * and the low-order 32 bits are taken from the low end of the IP6 address.
136  */
137 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
138 	/* struct in6_addr *ip6addr; */					\
139 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
140 {                                                                       \
141 	(enaddr)[0] = 0x33;						\
142 	(enaddr)[1] = 0x33;						\
143 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
144 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
145 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
146 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
147 }
148 #endif
149 
150 struct mii_data;
151 
152 struct ethercom;
153 
154 typedef int (*ether_cb_t)(struct ethercom *);
155 
156 /*
157  * Structure shared between the ethernet driver modules and
158  * the multicast list code.  For example, each ec_softc or il_softc
159  * begins with this structure.
160  */
161 struct ethercom {
162 	struct	ifnet ec_if;			/* network-visible interface */
163 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
164 						   addrs */
165 	int	ec_multicnt;			/* length of ec_multiaddrs
166 						   list */
167 	int	ec_capabilities;		/* capabilities, provided by
168 						   driver */
169 	int	ec_capenable;			/* tells hardware which
170 						   capabilities to enable */
171 
172 	int	ec_nvlans;			/* # VLANs on this interface */
173 	/* The device handle for the MII bus child device. */
174 	struct mii_data				*ec_mii;
175 	/* Called after a change to ec_if.if_flags.  Returns
176 	 * ENETRESET if the device should be reinitialized with
177 	 * ec_if.if_init, 0 on success, not 0 on failure.
178 	 */
179 	ether_cb_t				ec_ifflags_cb;
180 	kmutex_t				*ec_lock;
181 #ifdef MBUFTRACE
182 	struct	mowner ec_rx_mowner;		/* mbufs received */
183 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
184 #endif
185 };
186 
187 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
188 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
189 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
190 #define	ETHERCAP_MASK		0x00000007
191 
192 #define	ECCAPBITS		\
193 	"\020"			\
194 	"\1VLAN_MTU"		\
195 	"\2VLAN_HWTAGGING"	\
196 	"\3JUMBO_MTU"
197 
198 /* ioctl() for Ethernet capabilities */
199 struct eccapreq {
200 	char		eccr_name[IFNAMSIZ];	/* if name, e.g. "en0" */
201 	int		eccr_capabilities;	/* supported capabiliites */
202 	int		eccr_capenable;		/* capabilities enabled */
203 };
204 
205 #ifdef	_KERNEL
206 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
207 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
208 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
209 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
210 
211 void	ether_set_ifflags_cb(struct ethercom *, ether_cb_t);
212 int	ether_ioctl(struct ifnet *, u_long, void *);
213 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
214 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
215 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
216 void    ether_input(struct ifnet *, struct mbuf *);
217 #endif /* _KERNEL */
218 
219 /*
220  * Ethernet multicast address structure.  There is one of these for each
221  * multicast address or range of multicast addresses that we are supposed
222  * to listen to on a particular interface.  They are kept in a linked list,
223  * rooted in the interface's ethercom structure.
224  */
225 struct ether_multi {
226 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
227 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
228 	u_int	 enm_refcount;		/* no. claims to this addr/range */
229 	LIST_ENTRY(ether_multi) enm_list;
230 };
231 
232 struct ether_multi_sysctl {
233 	u_int   enm_refcount;
234 	uint8_t enm_addrlo[ETHER_ADDR_LEN];
235 	uint8_t enm_addrhi[ETHER_ADDR_LEN];
236 };
237 
238 /*
239  * Structure used by macros below to remember position when stepping through
240  * all of the ether_multi records.
241  */
242 struct ether_multistep {
243 	struct ether_multi  *e_enm;
244 };
245 
246 /*
247  * Macro for looking up the ether_multi record for a given range of Ethernet
248  * multicast addresses connected to a given ethercom structure.  If no matching
249  * record is found, "enm" returns NULL.
250  */
251 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
252 	/* uint8_t addrlo[ETHER_ADDR_LEN]; */				\
253 	/* uint8_t addrhi[ETHER_ADDR_LEN]; */				\
254 	/* struct ethercom *ec; */					\
255 	/* struct ether_multi *enm; */					\
256 {									\
257 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
258 	    (enm) != NULL &&						\
259 	    (memcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
260 	     memcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
261 		(enm) = LIST_NEXT((enm), enm_list));			\
262 }
263 
264 /*
265  * Macro to step through all of the ether_multi records, one at a time.
266  * The current position is remembered in "step", which the caller must
267  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
268  * and get the first record.  Both macros return a NULL "enm" when there
269  * are no remaining records.
270  */
271 #define ETHER_NEXT_MULTI(step, enm) \
272 	/* struct ether_multistep step; */  \
273 	/* struct ether_multi *enm; */  \
274 { \
275 	if (((enm) = (step).e_enm) != NULL) \
276 		(step).e_enm = LIST_NEXT((enm), enm_list); \
277 }
278 
279 #define ETHER_FIRST_MULTI(step, ec, enm) \
280 	/* struct ether_multistep step; */ \
281 	/* struct ethercom *ec; */ \
282 	/* struct ether_multi *enm; */ \
283 { \
284 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
285 	ETHER_NEXT_MULTI((step), (enm)); \
286 }
287 
288 #ifdef _KERNEL
289 
290 #define ETHER_LOCK(ec)		mutex_enter((ec)->ec_lock)
291 #define ETHER_UNLOCK(ec)	mutex_exit((ec)->ec_lock)
292 
293 /*
294  * Ethernet 802.1Q VLAN structures.
295  */
296 
297 /* add VLAN tag to input/received packet */
298 static inline int vlan_input_tag(struct ifnet *, struct mbuf *, u_int);
299 static inline int
300 vlan_input_tag(struct ifnet *ifp, struct mbuf *m, u_int vlanid)
301 {
302 	struct m_tag *mtag;
303 	mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int), M_NOWAIT);
304 	if (mtag == NULL) {
305 		ifp->if_ierrors++;
306 		printf("%s: unable to allocate VLAN tag\n", ifp->if_xname);
307 		m_freem(m);
308 		return 1;
309 	}
310 	*(u_int *)(mtag + 1) = vlanid;
311 	m_tag_prepend(m, mtag);
312 	return 0;
313 }
314 
315 #define VLAN_INPUT_TAG(ifp, m, vlanid, _errcase)		\
316     if (vlan_input_tag(ifp, m, vlanid) != 0) {	 		\
317 	_errcase;						\
318     }
319 
320 /* extract VLAN tag from output/trasmit packet */
321 #define VLAN_OUTPUT_TAG(ec, m0)			\
322 	(VLAN_ATTACHED(ec) ? m_tag_find((m0), PACKET_TAG_VLAN, NULL) : NULL)
323 
324 /* extract VLAN ID value from a VLAN tag */
325 #define VLAN_TAG_VALUE(mtag)	\
326 	((*(u_int *)(mtag + 1)) & 4095)
327 
328 /* test if any VLAN is configured for this interface */
329 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
330 
331 void	etherinit(void);
332 void	ether_ifattach(struct ifnet *, const uint8_t *);
333 void	ether_ifdetach(struct ifnet *);
334 int	ether_mediachange(struct ifnet *);
335 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
336 
337 char	*ether_sprintf(const uint8_t *);
338 char	*ether_snprintf(char *, size_t, const uint8_t *);
339 
340 uint32_t ether_crc32_le(const uint8_t *, size_t);
341 uint32_t ether_crc32_be(const uint8_t *, size_t);
342 
343 int	ether_aton_r(u_char *, size_t, const char *);
344 int	ether_enable_vlan_mtu(struct ifnet *);
345 int	ether_disable_vlan_mtu(struct ifnet *);
346 #else
347 /*
348  * Prototype ethers(3) functions.
349  */
350 #include <sys/cdefs.h>
351 __BEGIN_DECLS
352 char *	ether_ntoa(const struct ether_addr *);
353 struct ether_addr *
354 	ether_aton(const char *);
355 int	ether_ntohost(char *, const struct ether_addr *);
356 int	ether_hostton(const char *, struct ether_addr *);
357 int	ether_line(const char *, struct ether_addr *, char *);
358 __END_DECLS
359 #endif
360 
361 #endif /* _STANDALONE */
362 
363 #endif /* !_NET_IF_ETHER_H_ */
364