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      1 /*	$NetBSD: if_ether.h,v 1.91 2024/02/05 21:46:06 andvar 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  * Mbuf adjust factor to force 32-bit alignment of IP header.
     70  * Drivers should do m_adj(m, ETHER_ALIGN) when setting up a
     71  * receive so the upper layers get the IP header properly aligned
     72  * past the 14-byte Ethernet header.
     73  */
     74 #define	ETHER_ALIGN	2	/* driver adjust for IP hdr alignment */
     75 
     76 /*
     77  * Ethernet address - 6 octets
     78  * this is only used by the ethers(3) functions.
     79  */
     80 struct ether_addr {
     81 	uint8_t ether_addr_octet[ETHER_ADDR_LEN];
     82 };
     83 
     84 /*
     85  * Structure of a 10Mb/s Ethernet header.
     86  */
     87 struct ether_header {
     88 	uint8_t  ether_dhost[ETHER_ADDR_LEN];
     89 	uint8_t  ether_shost[ETHER_ADDR_LEN];
     90 	uint16_t ether_type;
     91 };
     92 
     93 #include <net/ethertypes.h>
     94 
     95 #define	ETHER_IS_MULTICAST(addr) (*(addr) & 0x01) /* is address mcast/bcast? */
     96 #define	ETHER_IS_LOCAL(addr) (*(addr) & 0x02) /* is address local? */
     97 
     98 #define	ETHERMTU_JUMBO	(ETHER_MAX_LEN_JUMBO - ETHER_HDR_LEN - ETHER_CRC_LEN)
     99 #define	ETHERMTU	(ETHER_MAX_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
    100 #define	ETHERMIN	(ETHER_MIN_LEN - ETHER_HDR_LEN - ETHER_CRC_LEN)
    101 
    102 /*
    103  * Compute the maximum frame size based on ethertype (i.e. possible
    104  * encapsulation) and whether or not an FCS is present.
    105  */
    106 #define	ETHER_MAX_FRAME(ifp, etype, hasfcs)				\
    107 	((ifp)->if_mtu + ETHER_HDR_LEN +				\
    108 	 ((hasfcs) ? ETHER_CRC_LEN : 0) +				\
    109 	 (((etype) == ETHERTYPE_VLAN) ? ETHER_VLAN_ENCAP_LEN : 0) +	\
    110 	 (((etype) == ETHERTYPE_PPPOE) ? ETHER_PPPOE_ENCAP_LEN : 0))
    111 
    112 /*
    113  * Ethernet CRC32 polynomials (big- and little-endian versions).
    114  */
    115 #define	ETHER_CRC_POLY_LE	0xedb88320
    116 #define	ETHER_CRC_POLY_BE	0x04c11db6
    117 
    118 #ifndef _STANDALONE
    119 
    120 /*
    121  * Ethernet-specific mbuf flags.
    122  */
    123 #define	M_HASFCS	M_LINK0	/* FCS included at end of frame */
    124 #define	M_PROMISC	M_LINK1	/* this packet is not for us */
    125 
    126 #ifdef _KERNEL
    127 /*
    128  * Macro to map an IP multicast address to an Ethernet multicast address.
    129  * The high-order 25 bits of the Ethernet address are statically assigned,
    130  * and the low-order 23 bits are taken from the low end of the IP address.
    131  */
    132 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr)				\
    133 	/* const struct in_addr *ipaddr; */				\
    134 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
    135 do {									\
    136 	(enaddr)[0] = 0x01;						\
    137 	(enaddr)[1] = 0x00;						\
    138 	(enaddr)[2] = 0x5e;						\
    139 	(enaddr)[3] = ((const uint8_t *)ipaddr)[1] & 0x7f;		\
    140 	(enaddr)[4] = ((const uint8_t *)ipaddr)[2];			\
    141 	(enaddr)[5] = ((const uint8_t *)ipaddr)[3];			\
    142 } while (/*CONSTCOND*/0)
    143 /*
    144  * Macro to map an IP6 multicast address to an Ethernet multicast address.
    145  * The high-order 16 bits of the Ethernet address are statically assigned,
    146  * and the low-order 32 bits are taken from the low end of the IP6 address.
    147  */
    148 #define ETHER_MAP_IPV6_MULTICAST(ip6addr, enaddr)			\
    149 	/* struct in6_addr *ip6addr; */					\
    150 	/* uint8_t enaddr[ETHER_ADDR_LEN]; */				\
    151 {                                                                       \
    152 	(enaddr)[0] = 0x33;						\
    153 	(enaddr)[1] = 0x33;						\
    154 	(enaddr)[2] = ((const uint8_t *)ip6addr)[12];			\
    155 	(enaddr)[3] = ((const uint8_t *)ip6addr)[13];			\
    156 	(enaddr)[4] = ((const uint8_t *)ip6addr)[14];			\
    157 	(enaddr)[5] = ((const uint8_t *)ip6addr)[15];			\
    158 }
    159 #endif
    160 
    161 struct mii_data;
    162 
    163 struct ethercom;
    164 
    165 typedef int (*ether_cb_t)(struct ethercom *);
    166 typedef int (*ether_vlancb_t)(struct ethercom *, uint16_t, bool);
    167 
    168 /*
    169  * Structure shared between the ethernet driver modules and
    170  * the multicast list code.  For example, each ec_softc or il_softc
    171  * begins with this structure.
    172  */
    173 struct ethercom {
    174 	struct	ifnet ec_if;			/* network-visible interface */
    175 	LIST_HEAD(, ether_multi) ec_multiaddrs;	/* list of ether multicast
    176 						   addrs */
    177 	int	ec_multicnt;			/* length of ec_multiaddrs
    178 						   list */
    179 	int	ec_capabilities;		/* capabilities, provided by
    180 						   driver */
    181 	int	ec_capenable;			/* tells hardware which
    182 						   capabilities to enable */
    183 
    184 	int	ec_nvlans;			/* # VLANs on this interface */
    185 	SIMPLEQ_HEAD(, vlanid_list) ec_vids;	/* list of VLAN IDs */
    186 	/* The device handle for the MII bus child device. */
    187 	struct mii_data				*ec_mii;
    188 	struct ifmedia				*ec_ifmedia;
    189 	/*
    190 	 * Called after a change to ec_if.if_flags.  Returns
    191 	 * ENETRESET if the device should be reinitialized with
    192 	 * ec_if.if_init, 0 on success, not 0 on failure.
    193 	 */
    194 	ether_cb_t				ec_ifflags_cb;
    195 	/*
    196 	 * Called whenever a vlan interface is configured or unconfigured.
    197 	 * Args include the vlan tag and a flag indicating whether the tag is
    198 	 * being added or removed.
    199 	 */
    200 	ether_vlancb_t				ec_vlan_cb;
    201 	/* Hooks called at the beginning of detach of this interface */
    202 	khook_list_t				*ec_ifdetach_hooks;
    203 	kmutex_t				*ec_lock;
    204 	/* Flags used only by the kernel */
    205 	int					ec_flags;
    206 #ifdef MBUFTRACE
    207 	struct	mowner ec_rx_mowner;		/* mbufs received */
    208 	struct	mowner ec_tx_mowner;		/* mbufs transmitted */
    209 #endif
    210 };
    211 
    212 #define	ETHERCAP_VLAN_MTU	0x00000001 /* VLAN-compatible MTU */
    213 #define	ETHERCAP_VLAN_HWTAGGING	0x00000002 /* hardware VLAN tag support */
    214 #define	ETHERCAP_JUMBO_MTU	0x00000004 /* 9000 byte MTU supported */
    215 #define	ETHERCAP_VLAN_HWFILTER	0x00000008 /* iface hw can filter vlan tag */
    216 #define	ETHERCAP_EEE		0x00000010 /* Energy Efficiency Ethernet */
    217 #define	ETHERCAP_MASK		0x0000001f
    218 
    219 #define	ECCAPBITS		\
    220 	"\020"			\
    221 	"\1VLAN_MTU"		\
    222 	"\2VLAN_HWTAGGING"	\
    223 	"\3JUMBO_MTU"		\
    224 	"\4VLAN_HWFILTER"	\
    225 	"\5EEE"
    226 
    227 /* ioctl() for Ethernet capabilities */
    228 struct eccapreq {
    229 	char		eccr_name[IFNAMSIZ];	/* if name, e.g. "en0" */
    230 	int		eccr_capabilities;	/* supported capabiliites */
    231 	int		eccr_capenable;		/* capabilities enabled */
    232 };
    233 
    234 /* sysctl for Ethernet multicast addresses */
    235 struct ether_multi_sysctl {
    236 	u_int   enm_refcount;
    237 	uint8_t enm_addrlo[ETHER_ADDR_LEN];
    238 	uint8_t enm_addrhi[ETHER_ADDR_LEN];
    239 };
    240 
    241 #ifdef	_KERNEL
    242 /*
    243  * Flags for ec_flags
    244  */
    245 /* Store IFF_ALLMULTI in ec_flags instead of if_flags to avoid data races. */
    246 #define ETHER_F_ALLMULTI	__BIT(0)
    247 
    248 extern const uint8_t etherbroadcastaddr[ETHER_ADDR_LEN];
    249 extern const uint8_t ethermulticastaddr_slowprotocols[ETHER_ADDR_LEN];
    250 extern const uint8_t ether_ipmulticast_min[ETHER_ADDR_LEN];
    251 extern const uint8_t ether_ipmulticast_max[ETHER_ADDR_LEN];
    252 
    253 void	ether_set_ifflags_cb(struct ethercom *, ether_cb_t);
    254 void	ether_set_vlan_cb(struct ethercom *, ether_vlancb_t);
    255 int	ether_ioctl(struct ifnet *, u_long, void *);
    256 int	ether_addmulti(const struct sockaddr *, struct ethercom *);
    257 int	ether_delmulti(const struct sockaddr *, struct ethercom *);
    258 int	ether_multiaddr(const struct sockaddr *, uint8_t[ETHER_ADDR_LEN],
    259 			uint8_t[ETHER_ADDR_LEN]);
    260 void    ether_input(struct ifnet *, struct mbuf *);
    261 
    262 /*
    263  * Ethernet multicast address structure.  There is one of these for each
    264  * multicast address or range of multicast addresses that we are supposed
    265  * to listen to on a particular interface.  They are kept in a linked list,
    266  * rooted in the interface's ethercom structure.
    267  */
    268 struct ether_multi {
    269 	uint8_t enm_addrlo[ETHER_ADDR_LEN]; /* low  or only address of range */
    270 	uint8_t enm_addrhi[ETHER_ADDR_LEN]; /* high or only address of range */
    271 	u_int	enm_refcount;		/* no. claims to this addr/range */
    272 	LIST_ENTRY(ether_multi) enm_list;
    273 };
    274 
    275 /*
    276  * Structure used by macros below to remember position when stepping through
    277  * all of the ether_multi records.
    278  */
    279 struct ether_multistep {
    280 	struct ether_multi  *e_enm;
    281 };
    282 
    283 /*
    284  * lookup the ether_multi record for a given range of Ethernet
    285  * multicast addresses connected to a given ethercom structure.
    286  * If no matching record is found, NULL is returned.
    287  */
    288 static __inline struct ether_multi *
    289 ether_lookup_multi(const uint8_t *addrlo, const uint8_t *addrhi,
    290     const struct ethercom *ec)
    291 {
    292 	struct ether_multi *enm;
    293 
    294 	LIST_FOREACH(enm, &ec->ec_multiaddrs, enm_list) {
    295 		if (memcmp(enm->enm_addrlo, addrlo, ETHER_ADDR_LEN) != 0)
    296 			continue;
    297 		if (memcmp(enm->enm_addrhi, addrhi, ETHER_ADDR_LEN) != 0)
    298 			continue;
    299 
    300 		break;
    301 	}
    302 
    303 	return enm;
    304 }
    305 
    306 /*
    307  * step through all of the ether_multi records, one at a time.
    308  * The current position is remembered in "step", which the caller must
    309  * provide.  ether_first_multi(), below, must be called to initialize "step"
    310  * and get the first record.  Both functions return a NULL when there
    311  * are no remaining records.
    312  */
    313 static __inline struct ether_multi *
    314 ether_next_multi(struct ether_multistep *step)
    315 {
    316 	struct ether_multi *enm;
    317 
    318 	enm = step->e_enm;
    319 	if (enm != NULL)
    320 		step->e_enm = LIST_NEXT(enm, enm_list);
    321 
    322 	return enm;
    323 }
    324 #define ETHER_NEXT_MULTI(step, enm)		\
    325 	/* struct ether_multistep step; */	\
    326 	/* struct ether_multi *enm; */		\
    327 	(enm) = ether_next_multi(&(step))
    328 
    329 static __inline struct ether_multi *
    330 ether_first_multi(struct ether_multistep *step, const struct ethercom *ec)
    331 {
    332 
    333 	step->e_enm = LIST_FIRST(&ec->ec_multiaddrs);
    334 
    335 	return ether_next_multi(step);
    336 }
    337 
    338 #define ETHER_FIRST_MULTI(step, ec, enm)		\
    339 	/* struct ether_multistep step; */		\
    340 	/* struct ethercom *ec; */			\
    341 	/* struct ether_multi *enm; */			\
    342 	(enm) = ether_first_multi(&(step), (ec))
    343 
    344 #define ETHER_LOCK(ec)		mutex_enter((ec)->ec_lock)
    345 #define ETHER_UNLOCK(ec)	mutex_exit((ec)->ec_lock)
    346 
    347 /*
    348  * Ethernet 802.1Q VLAN structures.
    349  */
    350 
    351 /* for ethercom */
    352 struct vlanid_list {
    353 	uint16_t vid;
    354 	SIMPLEQ_ENTRY(vlanid_list) vid_list;
    355 };
    356 
    357 /* add VLAN tag to input/received packet */
    358 static __inline void
    359 vlan_set_tag(struct mbuf *m, uint16_t vlantag)
    360 {
    361 	/* VLAN tag contains priority, CFI and VLAN ID */
    362 	KASSERT((m->m_flags & M_PKTHDR) != 0);
    363 	m->m_pkthdr.ether_vtag = vlantag;
    364 	m->m_flags |= M_VLANTAG;
    365 	return;
    366 }
    367 
    368 /* extract VLAN ID value from a VLAN tag */
    369 static __inline uint16_t
    370 vlan_get_tag(struct mbuf *m)
    371 {
    372 	KASSERT((m->m_flags & M_PKTHDR) != 0);
    373 	KASSERT(m->m_flags & M_VLANTAG);
    374 	return m->m_pkthdr.ether_vtag;
    375 }
    376 
    377 static __inline bool
    378 vlan_has_tag(struct mbuf *m)
    379 {
    380 	return (m->m_flags & M_VLANTAG) != 0;
    381 }
    382 
    383 static __inline bool
    384 vlan_is_hwtag_enabled(struct ifnet *_ifp)
    385 {
    386 	struct ethercom *ec = (void *)_ifp;
    387 
    388 	if (ec->ec_capenable & ETHERCAP_VLAN_HWTAGGING)
    389 		return true;
    390 
    391 	return false;
    392 }
    393 
    394 /* test if any VLAN is configured for this interface */
    395 #define VLAN_ATTACHED(ec)	((ec)->ec_nvlans > 0)
    396 
    397 void	etherinit(void);
    398 void	ether_ifattach(struct ifnet *, const uint8_t *);
    399 void	ether_ifdetach(struct ifnet *);
    400 int	ether_mediachange(struct ifnet *);
    401 void	ether_mediastatus(struct ifnet *, struct ifmediareq *);
    402 void *	ether_ifdetachhook_establish(struct ifnet *,
    403 	    void (*)(void *), void *arg);
    404 void	ether_ifdetachhook_disestablish(struct ifnet *,
    405 	    void *, kmutex_t *);
    406 
    407 char	*ether_sprintf(const uint8_t *);
    408 char	*ether_snprintf(char *, size_t, const uint8_t *);
    409 
    410 uint32_t ether_crc32_le(const uint8_t *, size_t);
    411 uint32_t ether_crc32_be(const uint8_t *, size_t);
    412 
    413 int	ether_aton_r(u_char *, size_t, const char *);
    414 int	ether_enable_vlan_mtu(struct ifnet *);
    415 int	ether_disable_vlan_mtu(struct ifnet *);
    416 int	ether_add_vlantag(struct ifnet *, uint16_t, bool *);
    417 int	ether_del_vlantag(struct ifnet *, uint16_t);
    418 int	ether_inject_vlantag(struct mbuf **, uint16_t, uint16_t);
    419 struct mbuf *
    420 	ether_strip_vlantag(struct mbuf *);
    421 #else
    422 /*
    423  * Prototype ethers(3) functions.
    424  */
    425 #include <sys/cdefs.h>
    426 __BEGIN_DECLS
    427 char *	ether_ntoa(const struct ether_addr *);
    428 struct ether_addr *
    429 	ether_aton(const char *);
    430 int	ether_ntohost(char *, const struct ether_addr *);
    431 int	ether_hostton(const char *, struct ether_addr *);
    432 int	ether_line(const char *, struct ether_addr *, char *);
    433 __END_DECLS
    434 #endif
    435 
    436 #endif /* _STANDALONE */
    437 
    438 #endif /* !_NET_IF_ETHER_H_ */
    439