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if_ether.h revision 1.43.2.1
      1 /*	$NetBSD: if_ether.h,v 1.43.2.1 2009/03/31 18:02:32 bouyer 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 	u_int8_t ether_addr_octet[ETHER_ADDR_LEN];
     67 } __attribute__((__packed__));
     68 
     69 /*
     70  * Structure of a 10Mb/s Ethernet header.
     71  */
     72 struct	ether_header {
     73 	u_int8_t  ether_dhost[ETHER_ADDR_LEN];
     74 	u_int8_t  ether_shost[ETHER_ADDR_LEN];
     75 	u_int16_t ether_type;
     76 } __attribute__((__packed__));
     77 
     78 #include <net/ethertypes.h>
     79 
     80 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
     81 
     82 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
     83 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
     84 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
     85 
     86 /*
     87  * Compute the maximum frame size based on ethertype (i.e. possible
     88  * encapsulation) and whether or not an FCS is present.
     89  */
     90 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
     91 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
     92 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
     93 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
     94 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
     95 
     96 /*
     97  * Ethernet CRC32 polynomials (big- and little-endian verions).
     98  */
     99 #define	ETHER_CRC_POLY_LE	0xedb88320
    100 #define	ETHER_CRC_POLY_BE	0x04c11db6
    101 
    102 #ifndef _STANDALONE
    103 
    104 /*
    105  * Ethernet-specific mbuf flags.
    106  */
    107 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
    108 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
    109 
    110 #ifdef _KERNEL
    111 /*
    112  * Macro to map an IP multicast address to an Ethernet multicast address.
    113  * The high-order 25 bits of the Ethernet address are statically assigned,
    114  * and the low-order 23 bits are taken from the low end of the IP address.
    115  */
    116 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
    117 	/* struct in_addr *ipaddr; */					\
    118 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
    119 {									\
    120 	(enaddr)[0] = 0x01;						\
    121 	(enaddr)[1] = 0x00;						\
    122 	(enaddr)[2] = 0x5e;						\
    123 	(enaddr)[3] = ((u_int8_t *)ipaddr)[1] & 0x7f;			\
    124 	(enaddr)[4] = ((u_int8_t *)ipaddr)[2];				\
    125 	(enaddr)[5] = ((u_int8_t *)ipaddr)[3];				\
    126 }
    127 /*
    128  * Macro to map an IP6 multicast address to an Ethernet multicast address.
    129  * The high-order 16 bits of the Ethernet address are statically assigned,
    130  * and the low-order 32 bits are taken from the low end of the IP6 address.
    131  */
    132 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
    133 	/* struct in6_addr *ip6addr; */					\
    134 	/* u_int8_t enaddr[ETHER_ADDR_LEN]; */				\
    135 {                                                                       \
    136 	(enaddr)[0] = 0x33;						\
    137 	(enaddr)[1] = 0x33;						\
    138 	(enaddr)[2] = ((u_int8_t *)ip6addr)[12];			\
    139 	(enaddr)[3] = ((u_int8_t *)ip6addr)[13];			\
    140 	(enaddr)[4] = ((u_int8_t *)ip6addr)[14];			\
    141 	(enaddr)[5] = ((u_int8_t *)ip6addr)[15];			\
    142 }
    143 #endif
    144 
    145 /*
    146  * Structure shared between the ethernet driver modules and
    147  * the multicast list code.  For example, each ec_softc or il_softc
    148  * begins with this structure.
    149  */
    150 struct	ethercom {
    151 	struct	ifnet ec_if;			/* network-visible interface */
    152 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
    153 						   addrs */
    154 	int	ec_multicnt;			/* length of ec_multiaddrs
    155 						   list */
    156 	int	ec_capabilities;		/* capabilities, provided by
    157 						   driver */
    158 	int	ec_capenable;			/* tells hardware which
    159 						   capabilities to enable */
    160 
    161 	int	ec_nvlans;			/* # VLANs on this interface */
    162 #ifdef MBUFTRACE
    163 	struct	mowner ec_rx_mowner;		/* mbufs received */
    164 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
    165 #endif
    166 };
    167 
    168 #define	ETHERCAP_VLAN_MTU	0x00000001	/* VLAN-compatible MTU */
    169 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002	/* hardware VLAN tag support */
    170 #define	ETHERCAP_JUMBO_MTU	0x00000004	/* 9000 byte MTU supported */
    171 
    172 #ifdef	_KERNEL
    173 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
    174 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
    175 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
    176 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
    177 
    178 int	ether_ioctl(struct ifnet *, u_long, caddr_t);
    179 int	ether_addmulti (struct ifreq *, struct ethercom *);
    180 int	ether_delmulti (struct ifreq *, struct ethercom *);
    181 int	ether_changeaddr (struct ifreq *, struct ethercom *);
    182 int	ether_multiaddr(struct sockaddr *, u_int8_t[], u_int8_t[]);
    183 #endif /* _KERNEL */
    184 
    185 /*
    186  * Ethernet multicast address structure.  There is one of these for each
    187  * multicast address or range of multicast addresses that we are supposed
    188  * to listen to on a particular interface.  They are kept in a linked list,
    189  * rooted in the interface's ethercom structure.
    190  */
    191 struct ether_multi {
    192 	u_int8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
    193 	u_int8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
    194 	u_int	 enm_refcount;		/* no. claims to this addr/range */
    195 	LIST_ENTRY(ether_multi) enm_list;
    196 };
    197 
    198 /*
    199  * Structure used by macros below to remember position when stepping through
    200  * all of the ether_multi records.
    201  */
    202 struct ether_multistep {
    203 	struct ether_multi  *e_enm;
    204 };
    205 
    206 /*
    207  * Macro for looking up the ether_multi record for a given range of Ethernet
    208  * multicast addresses connected to a given ethercom structure.  If no matching
    209  * record is found, "enm" returns NULL.
    210  */
    211 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ec, enm)			\
    212 	/* u_int8_t addrlo[ETHER_ADDR_LEN]; */				\
    213 	/* u_int8_t addrhi[ETHER_ADDR_LEN]; */				\
    214 	/* struct ethercom *ec; */					\
    215 	/* struct ether_multi *enm; */					\
    216 {									\
    217 	for ((enm) = LIST_FIRST(&(ec)->ec_multiaddrs);			\
    218 	    (enm) != NULL &&						\
    219 	    (bcmp((enm)->enm_addrlo, (addrlo), ETHER_ADDR_LEN) != 0 ||	\
    220 	     bcmp((enm)->enm_addrhi, (addrhi), ETHER_ADDR_LEN) != 0);	\
    221 		(enm) = LIST_NEXT((enm), enm_list));			\
    222 }
    223 
    224 /*
    225  * Macro to step through all of the ether_multi records, one at a time.
    226  * The current position is remembered in "step", which the caller must
    227  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
    228  * and get the first record.  Both macros return a NULL "enm" when there
    229  * are no remaining records.
    230  */
    231 #define ETHER_NEXT_MULTI(step, enm) \
    232 	/* struct ether_multistep step; */  \
    233 	/* struct ether_multi *enm; */  \
    234 { \
    235 	if (((enm) = (step).e_enm) != NULL) \
    236 		(step).e_enm = LIST_NEXT((enm), enm_list); \
    237 }
    238 
    239 #define ETHER_FIRST_MULTI(step, ec, enm) \
    240 	/* struct ether_multistep step; */ \
    241 	/* struct ethercom *ec; */ \
    242 	/* struct ether_multi *enm; */ \
    243 { \
    244 	(step).e_enm = LIST_FIRST(&(ec)->ec_multiaddrs); \
    245 	ETHER_NEXT_MULTI((step), (enm)); \
    246 }
    247 
    248 #ifdef _KERNEL
    249 
    250 /*
    251  * Ethernet 802.1Q VLAN structures.
    252  */
    253 
    254 /* add VLAN tag to input/received packet */
    255 #define	VLAN_INPUT_TAG(ifp, m, vlanid, _errcase)	\
    256 	do {								\
    257                 struct m_tag *mtag =					\
    258                     m_tag_get(PACKET_TAG_VLAN, sizeof(u_int), M_NOWAIT);\
    259                 if (mtag == NULL) {					\
    260 			ifp->if_ierrors++;				\
    261                         printf("%s: unable to allocate VLAN tag\n",	\
    262                             ifp->if_xname);				\
    263                         m_freem(m);					\
    264                         _errcase;					\
    265                 }							\
    266                 *(u_int *)(mtag + 1) = vlanid;				\
    267                 m_tag_prepend(m, mtag);					\
    268 	} while(0)
    269 
    270 /* extract VLAN tag from output/trasmit packet */
    271 #define VLAN_OUTPUT_TAG(ec, m0)			\
    272 	VLAN_ATTACHED(ec) ? m_tag_find((m0), PACKET_TAG_VLAN, NULL) : NULL
    273 
    274 /* extract VLAN ID value from a VLAN tag */
    275 #define VLAN_TAG_VALUE(mtag)	\
    276 	((*(u_int *)(mtag + 1)) & 4095)
    277 
    278 /* test if any VLAN is configured for this interface */
    279 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
    280 
    281 void	ether_ifattach(struct ifnet *, const u_int8_t *);
    282 void	ether_ifdetach(struct ifnet *);
    283 
    284 char	*ether_sprintf(const u_int8_t *);
    285 char	*ether_snprintf(char *, size_t, const u_int8_t *);
    286 
    287 u_int32_t ether_crc32_le(const u_int8_t *, size_t);
    288 u_int32_t ether_crc32_be(const u_int8_t *, size_t);
    289 
    290 int	ether_nonstatic_aton(u_char *, char *);
    291 #else
    292 /*
    293  * Prototype ethers(3) functions.
    294  */
    295 #include <sys/cdefs.h>
    296 __BEGIN_DECLS
    297 char *	ether_ntoa __P((const struct ether_addr *));
    298 struct ether_addr *
    299 	ether_aton __P((const char *));
    300 int	ether_ntohost __P((char *, const struct ether_addr *));
    301 int	ether_hostton __P((const char *, struct ether_addr *));
    302 int	ether_line __P((const char *, struct ether_addr *, char *));
    303 __END_DECLS
    304 #endif
    305 
    306 #endif /* _STANDALONE */
    307 
    308 #endif /* !_NET_IF_ETHER_H_ */
    309