xref: /freebsd/sys/netinet/if_ether.h (revision afe61c15161c324a7af299a9b8457aba5afc92db)
1 /*
2  * Copyright (c) 1982, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)if_ether.h	8.1 (Berkeley) 6/10/93
34  */
35 
36 /*
37  * Structure of a 10Mb/s Ethernet header.
38  */
39 struct	ether_header {
40 	u_char	ether_dhost[6];
41 	u_char	ether_shost[6];
42 	u_short	ether_type;
43 };
44 
45 #define	ETHERTYPE_PUP		0x0200	/* PUP protocol */
46 #define	ETHERTYPE_IP		0x0800	/* IP protocol */
47 #define ETHERTYPE_ARP		0x0806	/* Addr. resolution protocol */
48 #define ETHERTYPE_REVARP	0x8035	/* reverse Addr. resolution protocol */
49 
50 /*
51  * The ETHERTYPE_NTRAILER packet types starting at ETHERTYPE_TRAIL have
52  * (type-ETHERTYPE_TRAIL)*512 bytes of data followed
53  * by an ETHER type (as given above) and then the (variable-length) header.
54  */
55 #define	ETHERTYPE_TRAIL		0x1000		/* Trailer packet */
56 #define	ETHERTYPE_NTRAILER	16
57 
58 #define	ETHERMTU	1500
59 #define	ETHERMIN	(60-14)
60 
61 #ifdef KERNEL
62 /*
63  * Macro to map an IP multicast address to an Ethernet multicast address.
64  * The high-order 25 bits of the Ethernet address are statically assigned,
65  * and the low-order 23 bits are taken from the low end of the IP address.
66  */
67 #define ETHER_MAP_IP_MULTICAST(ipaddr, enaddr) \
68 	/* struct in_addr *ipaddr; */ \
69 	/* u_char enaddr[6];	   */ \
70 { \
71 	(enaddr)[0] = 0x01; \
72 	(enaddr)[1] = 0x00; \
73 	(enaddr)[2] = 0x5e; \
74 	(enaddr)[3] = ((u_char *)ipaddr)[1] & 0x7f; \
75 	(enaddr)[4] = ((u_char *)ipaddr)[2]; \
76 	(enaddr)[5] = ((u_char *)ipaddr)[3]; \
77 }
78 #endif
79 
80 /*
81  * Ethernet Address Resolution Protocol.
82  *
83  * See RFC 826 for protocol description.  Structure below is adapted
84  * to resolving internet addresses.  Field names used correspond to
85  * RFC 826.
86  */
87 struct	ether_arp {
88 	struct	arphdr ea_hdr;	/* fixed-size header */
89 	u_char	arp_sha[6];	/* sender hardware address */
90 	u_char	arp_spa[4];	/* sender protocol address */
91 	u_char	arp_tha[6];	/* target hardware address */
92 	u_char	arp_tpa[4];	/* target protocol address */
93 };
94 #define	arp_hrd	ea_hdr.ar_hrd
95 #define	arp_pro	ea_hdr.ar_pro
96 #define	arp_hln	ea_hdr.ar_hln
97 #define	arp_pln	ea_hdr.ar_pln
98 #define	arp_op	ea_hdr.ar_op
99 
100 
101 /*
102  * Structure shared between the ethernet driver modules and
103  * the address resolution code.  For example, each ec_softc or il_softc
104  * begins with this structure.
105  */
106 struct	arpcom {
107 	struct 	ifnet ac_if;		/* network-visible interface */
108 	u_char	ac_enaddr[6];		/* ethernet hardware address */
109 	struct	in_addr ac_ipaddr;	/* copy of ip address- XXX */
110 	struct	ether_multi *ac_multiaddrs; /* list of ether multicast addrs */
111 	int	ac_multicnt;		/* length of ac_multiaddrs list */
112 };
113 
114 struct llinfo_arp {
115 	struct	llinfo_arp *la_next;
116 	struct	llinfo_arp *la_prev;
117 	struct	rtentry *la_rt;
118 	struct	mbuf *la_hold;		/* last packet until resolved/timeout */
119 	long	la_asked;		/* last time we QUERIED for this addr */
120 #define la_timer la_rt->rt_rmx.rmx_expire /* deletion time in seconds */
121 };
122 
123 struct sockaddr_inarp {
124 	u_char	sin_len;
125 	u_char	sin_family;
126 	u_short sin_port;
127 	struct	in_addr sin_addr;
128 	struct	in_addr sin_srcaddr;
129 	u_short	sin_tos;
130 	u_short	sin_other;
131 #define SIN_PROXY 1
132 };
133 /*
134  * IP and ethernet specific routing flags
135  */
136 #define	RTF_USETRAILERS	RTF_PROTO1	/* use trailers */
137 #define RTF_ANNOUNCE	RTF_PROTO2	/* announce new arp entry */
138 
139 #ifdef	KERNEL
140 u_char	etherbroadcastaddr[6];
141 u_char	ether_ipmulticast_min[6];
142 u_char	ether_ipmulticast_max[6];
143 struct	ifqueue arpintrq;
144 
145 struct	llinfo_arp *arptnew __P((struct in_addr *));
146 struct	llinfo_arp llinfo_arp;		/* head of the llinfo queue */
147 
148 void	arpwhohas __P((struct arpcom *, struct in_addr *));
149 void	arpintr __P((void));
150 int	arpresolve __P((struct arpcom *,
151 	   struct rtentry *, struct mbuf *, struct sockaddr *, u_char *));
152 void	arp_rtrequest __P((int, struct rtentry *, struct sockaddr *));
153 void	arpwhohas __P((struct arpcom *, struct in_addr *));
154 
155 int	ether_addmulti __P((struct ifreq *, struct arpcom *));
156 int	ether_delmulti __P((struct ifreq *, struct arpcom *));
157 
158 /*
159  * Ethernet multicast address structure.  There is one of these for each
160  * multicast address or range of multicast addresses that we are supposed
161  * to listen to on a particular interface.  They are kept in a linked list,
162  * rooted in the interface's arpcom structure.  (This really has nothing to
163  * do with ARP, or with the Internet address family, but this appears to be
164  * the minimally-disrupting place to put it.)
165  */
166 struct ether_multi {
167 	u_char	enm_addrlo[6];		/* low  or only address of range */
168 	u_char	enm_addrhi[6];		/* high or only address of range */
169 	struct	arpcom *enm_ac;		/* back pointer to arpcom */
170 	u_int	enm_refcount;		/* no. claims to this addr/range */
171 	struct	ether_multi *enm_next;	/* ptr to next ether_multi */
172 };
173 
174 /*
175  * Structure used by macros below to remember position when stepping through
176  * all of the ether_multi records.
177  */
178 struct ether_multistep {
179 	struct ether_multi  *e_enm;
180 };
181 
182 /*
183  * Macro for looking up the ether_multi record for a given range of Ethernet
184  * multicast addresses connected to a given arpcom structure.  If no matching
185  * record is found, "enm" returns NULL.
186  */
187 #define ETHER_LOOKUP_MULTI(addrlo, addrhi, ac, enm) \
188 	/* u_char addrlo[6]; */ \
189 	/* u_char addrhi[6]; */ \
190 	/* struct arpcom *ac; */ \
191 	/* struct ether_multi *enm; */ \
192 { \
193 	for ((enm) = (ac)->ac_multiaddrs; \
194 	    (enm) != NULL && \
195 	    (bcmp((enm)->enm_addrlo, (addrlo), 6) != 0 || \
196 	     bcmp((enm)->enm_addrhi, (addrhi), 6) != 0); \
197 		(enm) = (enm)->enm_next); \
198 }
199 
200 /*
201  * Macro to step through all of the ether_multi records, one at a time.
202  * The current position is remembered in "step", which the caller must
203  * provide.  ETHER_FIRST_MULTI(), below, must be called to initialize "step"
204  * and get the first record.  Both macros return a NULL "enm" when there
205  * are no remaining records.
206  */
207 #define ETHER_NEXT_MULTI(step, enm) \
208 	/* struct ether_multistep step; */  \
209 	/* struct ether_multi *enm; */  \
210 { \
211 	if (((enm) = (step).e_enm) != NULL) \
212 		(step).e_enm = (enm)->enm_next; \
213 }
214 
215 #define ETHER_FIRST_MULTI(step, ac, enm) \
216 	/* struct ether_multistep step; */ \
217 	/* struct arpcom *ac; */ \
218 	/* struct ether_multi *enm; */ \
219 { \
220 	(step).e_enm = (ac)->ac_multiaddrs; \
221 	ETHER_NEXT_MULTI((step), (enm)); \
222 }
223 
224 #endif
225