1 /*
2 * Copyright (c) 1982, 1986 Regents of the University of California.
3 * 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 * $Id: $
34 *
35 * Ethernet Link Layer.
36 */
37
38 /*
39 * Structure of a 10Mb/s Ethernet header.
40 */
41 struct ether_header {
42 u_char ether_dhost[6];
43 u_char ether_shost[6];
44 u_short ether_type;
45 };
46
47 #define ETHERTYPE_PUP 0x0200 /* PUP protocol */
48 #define ETHERTYPE_IP 0x0800 /* IP protocol */
49 #define ETHERTYPE_ARP 0x0806 /* Addr. resolution protocol */
50
51 /*
52 * The ETHERTYPE_NTRAILER packet types starting at ETHERTYPE_TRAIL have
53 * (type-ETHERTYPE_TRAIL)*512 bytes of data followed
54 * by an ETHER type (as given above) and then the (variable-length) header.
55 */
56 #define ETHERTYPE_TRAIL 0x1000 /* Trailer packet */
57 #define ETHERTYPE_NTRAILER 16
58
59 #define ETHERMTU 1500
60 #define ETHERMIN (60-14)
61
62 /*
63 * Ethernet Address Resolution Protocol.
64 *
65 * See RFC 826 for protocol description. Structure below is adapted
66 * to resolving internet addresses. Field names used correspond to
67 * RFC 826.
68 */
69 struct ether_arp {
70 struct arphdr ea_hdr; /* fixed-size header */
71 u_char arp_sha[6]; /* sender hardware address */
72 u_char arp_spa[4]; /* sender protocol address */
73 u_char arp_tha[6]; /* target hardware address */
74 u_char arp_tpa[4]; /* target protocol address */
75 };
76 #define arp_hrd ea_hdr.ar_hrd
77 #define arp_pro ea_hdr.ar_pro
78 #define arp_hln ea_hdr.ar_hln
79 #define arp_pln ea_hdr.ar_pln
80 #define arp_op ea_hdr.ar_op
81
82
83 /*
84 * Structure shared between the ethernet driver modules and
85 * the address resolution code. For example, each ec_softc or il_softc
86 * begins with this structure.
87 */
88 struct arpcom {
89 struct ifnet ac_if; /* network-visible interface */
90 u_char ac_enaddr[6]; /* ethernet hardware address */
91 struct in_addr ac_ipaddr; /* copy of ip address- XXX */
92 };
93
94 /*
95 * Internet to ethernet address resolution table.
96 */
97 struct arptab {
98 struct in_addr at_iaddr; /* internet address */
99 u_char at_enaddr[6]; /* ethernet address */
100 u_char at_timer; /* minutes since last reference */
101 u_char at_flags; /* flags */
102 struct mbuf *at_hold; /* last packet until resolved/timeout */
103 };
104
105 #ifdef KERNEL
106 /*u_char etherbroadcastaddr[6];
107 struct arptab *arptnew();*/
108 struct arptab *arptnew(struct in_addr *);
109
110 /* interface symbols */
111 #define __ISYM_VERSION__ "1" /* XXX RCS major revision number of hdr file */
112 #include "isym.h" /* this header has interface symbols */
113
114 /* global variables used in core kernel and other modules */
115 __ISYM__(u_char, etherbroadcastaddr, [6])
116
117 /* functions used in modules */
118 __ISYM__(void, ether_input, (struct ifnet *, struct ether_header *, struct mbuf *))
119 __ISYM__(int, ether_output, (struct ifnet *, struct mbuf *, struct sockaddr *, struct rtentry *))
120 __ISYM__(char *, ether_sprintf, (u_char *))
121
122 #undef __ISYM__
123 #undef __ISYM_ALIAS__
124 #undef __ISYM_VERSION__
125
126 #ifndef _ARP_PROTOTYPES
127 /* private arp functions, accessed via external symbol stub when loaded */
128 static void arpwhohas(struct arpcom *, struct in_addr *);
129 static void arpinput(struct arpcom *ac, struct mbuf *m);
130 static int arpresolve(struct arpcom *ac, struct mbuf *m, struct in_addr *destip,
131 u_char *desten, int *usetrailers);
132
133 /* inline external symbol table function stubs */
134 extern inline void
arpwhohas(struct arpcom * a,struct in_addr * i)135 arpwhohas(struct arpcom *a, struct in_addr *i) {
136 void (*f)(struct arpcom *, struct in_addr *);
137
138 (const void *) f = esym_fetch(arpwhohas);
139 if (f == 0)
140 return;
141 (*f)(a, i);
142 }
143 extern inline void
arpinput(struct arpcom * a,struct mbuf * m)144 arpinput(struct arpcom *a, struct mbuf *m) {
145 void (*f)(struct arpcom *, struct mbuf *);
146
147 (const void *) f = esym_fetch(arpinput);
148 if (f == 0)
149 return;
150 (*f)(a, m);
151 }
152 extern inline int
arpresolve(struct arpcom * a,struct mbuf * m,struct in_addr * d,u_char * c,int * u)153 arpresolve(struct arpcom *a, struct mbuf *m, struct in_addr *d, u_char *c, int *u) {
154 int (*f)(struct arpcom *, struct mbuf *, struct in_addr *, u_char *, int *);
155
156 (const void *) f = esym_fetch(arpresolve);
157 if (f == 0)
158 return (0);
159 return ((*f)(a, m, d, c, u));
160 }
161 #else
162 extern void arpwhohas(struct arpcom *, struct in_addr *);
163 extern void arpinput(struct arpcom *ac, struct mbuf *m);
164 extern int arpresolve(struct arpcom *ac, struct mbuf *m, struct in_addr *destip,
165 u_char *desten, int *usetrailers);
166 #endif /* _ARP_PROTOTYPES */
167 #endif
168