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 *
ether_lookup_multi(const uint8_t * addrlo,const uint8_t * addrhi,const struct ethercom * ec)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 *
ether_next_multi(struct ether_multistep * step)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 *
ether_first_multi(struct ether_multistep * step,const struct ethercom * ec)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
vlan_set_tag(struct mbuf * m,uint16_t vlantag)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
vlan_get_tag(struct mbuf * m)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
vlan_has_tag(struct mbuf * m)378 vlan_has_tag(struct mbuf *m)
379 {
380           return (m->m_flags & M_VLANTAG) != 0;
381 }
382 
383 static __inline bool
vlan_is_hwtag_enabled(struct ifnet * _ifp)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