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if_ether.h revision 1.58
      1 /*	$NetBSD: if_ether.h,v 1.58 2010/05/19 20:41:59 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 /*
     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 struct ethercom;
    149 
    150 typedef int (*ether_cb_t)(struct ethercom *);
    151 
    152 /*
    153  * Structure shared between the ethernet driver modules and
    154  * the multicast list code.  For example, each ec_softc or il_softc
    155  * begins with this structure.
    156  */
    157 struct ethercom {
    158 	struct	ifnet ec_if;			/* network-visible interface */
    159 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
    160 						   addrs */
    161 	int	ec_multicnt;			/* length of ec_multiaddrs
    162 						   list */
    163 	int	ec_capabilities;		/* capabilities, provided by
    164 						   driver */
    165 	int	ec_capenable;			/* tells hardware which
    166 						   capabilities to enable */
    167 
    168 	int	ec_nvlans;			/* # VLANs on this interface */
    169 	/* The device handle for the MII bus child device. */
    170 	struct mii_data				*ec_mii;
    171 	/* Called after a change to ec_if.if_flags.  Returns
    172 	 * ENETRESET if the device should be reinitialized with
    173 	 * ec_if.if_init, 0 on success, not 0 on failure.
    174 	 */
    175 	ether_cb_t				ec_ifflags_cb;
    176 #ifdef MBUFTRACE
    177 	struct	mowner ec_rx_mowner;		/* mbufs received */
    178 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
    179 #endif
    180 };
    181 
    182 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
    183 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
    184 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
    185 
    186 #ifdef	_KERNEL
    187 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
    188 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
    189 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
    190 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
    191 
    192 void	ether_set_ifflags_cb(struct ethercom *, ether_cb_t);
    193 int	ether_ioctl(struct ifnet *, u_long, void *);
    194 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
    195 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
    196 int	ether_multiaddr(const struct sockaddr *, uint8_t[], uint8_t[]);
    197 #endif /* _KERNEL */
    198 
    199 /*
    200  * Ethernet multicast address structure.  There is one of these for each
    201  * multicast address or range of multicast addresses that we are supposed
    202  * to listen to on a particular interface.  They are kept in a linked list,
    203  * rooted in the interface's ethercom structure.
    204  */
    205 struct ether_multi {
    206 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
    207 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
    208 	u_int	 enm_refcount;		/* no. claims to this addr/range */
    209 	LIST_ENTRY(ether_multi) enm_list;
    210 };
    211 
    212 /*
    213  * Structure used by macros below to remember position when stepping through
    214  * all of the ether_multi records.
    215  */
    216 struct ether_multistep {
    217 	struct ether_multi  *e_enm;
    218 };
    219 
    220 /*
    221  * Macro for looking up the ether_multi record for a given range of Ethernet
    222  * multicast addresses connected to a given ethercom structure.  If no matching
    223  * record is found, "enm" returns NULL.
    224  */
    225 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
    226 	/* uint8_t addrlo[ETHER_ADDR_LEN]; */				\
    227 	/* uint8_t addrhi[ETHER_ADDR_LEN]; */				\
    228 	/* struct ethercom *ec; */					\
    229 	/* struct ether_multi *enm; */					\
    230 {									\
    231 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
    232 	    (enm) != NULL &&						\
    233 	    (memcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
    234 	     memcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
    235 		(enm) = LIST_NEXT((enm), enm_list));			\
    236 }
    237 
    238 /*
    239  * Macro to step through all of the ether_multi records, one at a time.
    240  * The current position is remembered in "step", which the caller must
    241  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
    242  * and get the first record.  Both macros return a NULL "enm" when there
    243  * are no remaining records.
    244  */
    245 #define ETHER_NEXT_MULTI(step, enm) \
    246 	/* struct ether_multistep step; */  \
    247 	/* struct ether_multi *enm; */  \
    248 { \
    249 	if (((enm) = (step).e_enm) != NULL) \
    250 		(step).e_enm = LIST_NEXT((enm), enm_list); \
    251 }
    252 
    253 #define ETHER_FIRST_MULTI(step, ec, enm) \
    254 	/* struct ether_multistep step; */ \
    255 	/* struct ethercom *ec; */ \
    256 	/* struct ether_multi *enm; */ \
    257 { \
    258 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
    259 	ETHER_NEXT_MULTI((step), (enm)); \
    260 }
    261 
    262 #ifdef _KERNEL
    263 
    264 /*
    265  * Ethernet 802.1Q VLAN structures.
    266  */
    267 
    268 /* add VLAN tag to input/received packet */
    269 static inline int vlan_input_tag(struct ifnet *, struct mbuf *, u_int);
    270 static inline int
    271 vlan_input_tag(struct ifnet *ifp, struct mbuf *m, u_int vlanid)
    272 {
    273 	struct m_tag *mtag;
    274 	mtag = m_tag_get(PACKET_TAG_VLAN, sizeof(u_int), M_NOWAIT);
    275 	if (mtag == NULL) {
    276 		ifp->if_ierrors++;
    277 		printf("%s: unable to allocate VLAN tag\n", ifp->if_xname);
    278 		m_freem(m);
    279 		return 1;
    280 	}
    281 	*(u_int *)(mtag + 1) = vlanid;
    282 	m_tag_prepend(m, mtag);
    283 	return 0;
    284 }
    285 
    286 #define VLAN_INPUT_TAG(ifp, m, vlanid, _errcase)		\
    287     if (vlan_input_tag(ifp, m, vlanid) != 0) {	 		\
    288 	_errcase;						\
    289     }
    290 
    291 /* extract VLAN tag from output/trasmit packet */
    292 #define VLAN_OUTPUT_TAG(ec, m0)			\
    293 	(VLAN_ATTACHED(ec) ? m_tag_find((m0), PACKET_TAG_VLAN, NULL) : NULL)
    294 
    295 /* extract VLAN ID value from a VLAN tag */
    296 #define VLAN_TAG_VALUE(mtag)	\
    297 	((*(u_int *)(mtag + 1)) & 4095)
    298 
    299 /* test if any VLAN is configured for this interface */
    300 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
    301 
    302 void	ether_ifattach(struct ifnet *, const uint8_t *);
    303 void	ether_ifdetach(struct ifnet *);
    304 int	ether_mediachange(struct ifnet *);
    305 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
    306 
    307 char	*ether_sprintf(const uint8_t *);
    308 char	*ether_snprintf(char *, size_t, const uint8_t *);
    309 
    310 uint32_t ether_crc32_le(const uint8_t *, size_t);
    311 uint32_t ether_crc32_be(const uint8_t *, size_t);
    312 
    313 int	ether_aton_r(u_char *, size_t, const char *);
    314 #else
    315 /*
    316  * Prototype ethers(3) functions.
    317  */
    318 #include <sys/cdefs.h>
    319 __BEGIN_DECLS
    320 char *	ether_ntoa(const struct ether_addr *);
    321 struct ether_addr *
    322 	ether_aton(const char *);
    323 int	ether_ntohost(char *, const struct ether_addr *);
    324 int	ether_hostton(const char *, struct ether_addr *);
    325 int	ether_line(const char *, struct ether_addr *, char *);
    326 __END_DECLS
    327 #endif
    328 
    329 #endif /* _STANDALONE */
    330 
    331 #endif /* !_NET_IF_ETHER_H_ */
    332