1*479ab7f0SSascha Wildner /* $NetBSD: rarp.c,v 1.16 1997/07/07 15:52:52 drochner Exp $ */
2*479ab7f0SSascha Wildner /* $DragonFly: src/lib/libstand/rarp.c,v 1.3 2005/12/11 02:27:26 swildner Exp $ */
3*479ab7f0SSascha Wildner
4*479ab7f0SSascha Wildner /*
5*479ab7f0SSascha Wildner * Copyright (c) 1992 Regents of the University of California.
6*479ab7f0SSascha Wildner * All rights reserved.
7*479ab7f0SSascha Wildner *
8*479ab7f0SSascha Wildner * This software was developed by the Computer Systems Engineering group
9*479ab7f0SSascha Wildner * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
10*479ab7f0SSascha Wildner * contributed to Berkeley.
11*479ab7f0SSascha Wildner *
12*479ab7f0SSascha Wildner * Redistribution and use in source and binary forms, with or without
13*479ab7f0SSascha Wildner * modification, are permitted provided that the following conditions
14*479ab7f0SSascha Wildner * are met:
15*479ab7f0SSascha Wildner * 1. Redistributions of source code must retain the above copyright
16*479ab7f0SSascha Wildner * notice, this list of conditions and the following disclaimer.
17*479ab7f0SSascha Wildner * 2. Redistributions in binary form must reproduce the above copyright
18*479ab7f0SSascha Wildner * notice, this list of conditions and the following disclaimer in the
19*479ab7f0SSascha Wildner * documentation and/or other materials provided with the distribution.
20*479ab7f0SSascha Wildner * 3. Neither the name of the University nor the names of its contributors
21*479ab7f0SSascha Wildner * may be used to endorse or promote products derived from this software
22*479ab7f0SSascha Wildner * without specific prior written permission.
23*479ab7f0SSascha Wildner *
24*479ab7f0SSascha Wildner * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25*479ab7f0SSascha Wildner * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26*479ab7f0SSascha Wildner * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27*479ab7f0SSascha Wildner * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28*479ab7f0SSascha Wildner * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29*479ab7f0SSascha Wildner * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30*479ab7f0SSascha Wildner * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31*479ab7f0SSascha Wildner * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32*479ab7f0SSascha Wildner * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33*479ab7f0SSascha Wildner * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34*479ab7f0SSascha Wildner * SUCH DAMAGE.
35*479ab7f0SSascha Wildner *
36*479ab7f0SSascha Wildner * @(#) Header: arp.c,v 1.5 93/07/15 05:52:26 leres Exp (LBL)
37*479ab7f0SSascha Wildner */
38*479ab7f0SSascha Wildner #include <sys/param.h>
39*479ab7f0SSascha Wildner #include <sys/socket.h>
40*479ab7f0SSascha Wildner #include <net/if.h>
41*479ab7f0SSascha Wildner #include <netinet/in.h>
42*479ab7f0SSascha Wildner #include <netinet/if_ether.h>
43*479ab7f0SSascha Wildner
44*479ab7f0SSascha Wildner #include <netinet/in_systm.h>
45*479ab7f0SSascha Wildner
46*479ab7f0SSascha Wildner #include <string.h>
47*479ab7f0SSascha Wildner
48*479ab7f0SSascha Wildner #include "stand.h"
49*479ab7f0SSascha Wildner #include "net.h"
50*479ab7f0SSascha Wildner #include "netif.h"
51*479ab7f0SSascha Wildner
52*479ab7f0SSascha Wildner
53*479ab7f0SSascha Wildner static ssize_t rarpsend(struct iodesc *, void *, size_t);
54*479ab7f0SSascha Wildner static ssize_t rarprecv(struct iodesc *, void *, size_t, time_t);
55*479ab7f0SSascha Wildner
56*479ab7f0SSascha Wildner /*
57*479ab7f0SSascha Wildner * Ethernet (Reverse) Address Resolution Protocol (see RFC 903, and 826).
58*479ab7f0SSascha Wildner */
59*479ab7f0SSascha Wildner int
rarp_getipaddress(int sock)60*479ab7f0SSascha Wildner rarp_getipaddress(int sock)
61*479ab7f0SSascha Wildner {
62*479ab7f0SSascha Wildner struct iodesc *d;
63*479ab7f0SSascha Wildner struct ether_arp *ap;
64*479ab7f0SSascha Wildner struct {
65*479ab7f0SSascha Wildner u_char header[ETHER_SIZE];
66*479ab7f0SSascha Wildner struct {
67*479ab7f0SSascha Wildner struct ether_arp arp;
68*479ab7f0SSascha Wildner u_char pad[18]; /* 60 - sizeof(arp) */
69*479ab7f0SSascha Wildner } data;
70*479ab7f0SSascha Wildner } wbuf;
71*479ab7f0SSascha Wildner struct {
72*479ab7f0SSascha Wildner u_char header[ETHER_SIZE];
73*479ab7f0SSascha Wildner struct {
74*479ab7f0SSascha Wildner struct ether_arp arp;
75*479ab7f0SSascha Wildner u_char pad[24]; /* extra space */
76*479ab7f0SSascha Wildner } data;
77*479ab7f0SSascha Wildner } rbuf;
78*479ab7f0SSascha Wildner
79*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
80*479ab7f0SSascha Wildner if (debug)
81*479ab7f0SSascha Wildner printf("rarp: socket=%d\n", sock);
82*479ab7f0SSascha Wildner #endif
83*479ab7f0SSascha Wildner if (!(d = socktodesc(sock))) {
84*479ab7f0SSascha Wildner printf("rarp: bad socket. %d\n", sock);
85*479ab7f0SSascha Wildner return (-1);
86*479ab7f0SSascha Wildner }
87*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
88*479ab7f0SSascha Wildner if (debug)
89*479ab7f0SSascha Wildner printf("rarp: d=%x\n", (u_int)d);
90*479ab7f0SSascha Wildner #endif
91*479ab7f0SSascha Wildner
92*479ab7f0SSascha Wildner bzero((char*)&wbuf.data, sizeof(wbuf.data));
93*479ab7f0SSascha Wildner ap = &wbuf.data.arp;
94*479ab7f0SSascha Wildner ap->arp_hrd = htons(ARPHRD_ETHER);
95*479ab7f0SSascha Wildner ap->arp_pro = htons(ETHERTYPE_IP);
96*479ab7f0SSascha Wildner ap->arp_hln = sizeof(ap->arp_sha); /* hardware address length */
97*479ab7f0SSascha Wildner ap->arp_pln = sizeof(ap->arp_spa); /* protocol address length */
98*479ab7f0SSascha Wildner ap->arp_op = htons(ARPOP_REVREQUEST);
99*479ab7f0SSascha Wildner bcopy(d->myea, ap->arp_sha, 6);
100*479ab7f0SSascha Wildner bcopy(d->myea, ap->arp_tha, 6);
101*479ab7f0SSascha Wildner
102*479ab7f0SSascha Wildner if (sendrecv(d,
103*479ab7f0SSascha Wildner rarpsend, &wbuf.data, sizeof(wbuf.data),
104*479ab7f0SSascha Wildner rarprecv, &rbuf.data, sizeof(rbuf.data)) < 0)
105*479ab7f0SSascha Wildner {
106*479ab7f0SSascha Wildner printf("No response for RARP request\n");
107*479ab7f0SSascha Wildner return (-1);
108*479ab7f0SSascha Wildner }
109*479ab7f0SSascha Wildner
110*479ab7f0SSascha Wildner ap = &rbuf.data.arp;
111*479ab7f0SSascha Wildner bcopy(ap->arp_tpa, (char *)&myip, sizeof(myip));
112*479ab7f0SSascha Wildner #if 0
113*479ab7f0SSascha Wildner /* XXX - Can NOT assume this is our root server! */
114*479ab7f0SSascha Wildner bcopy(ap->arp_spa, (char *)&rootip, sizeof(rootip));
115*479ab7f0SSascha Wildner #endif
116*479ab7f0SSascha Wildner
117*479ab7f0SSascha Wildner /* Compute our "natural" netmask. */
118*479ab7f0SSascha Wildner if (IN_CLASSA(myip.s_addr))
119*479ab7f0SSascha Wildner netmask = IN_CLASSA_NET;
120*479ab7f0SSascha Wildner else if (IN_CLASSB(myip.s_addr))
121*479ab7f0SSascha Wildner netmask = IN_CLASSB_NET;
122*479ab7f0SSascha Wildner else
123*479ab7f0SSascha Wildner netmask = IN_CLASSC_NET;
124*479ab7f0SSascha Wildner
125*479ab7f0SSascha Wildner d->myip = myip;
126*479ab7f0SSascha Wildner return (0);
127*479ab7f0SSascha Wildner }
128*479ab7f0SSascha Wildner
129*479ab7f0SSascha Wildner /*
130*479ab7f0SSascha Wildner * Broadcast a RARP request (i.e. who knows who I am)
131*479ab7f0SSascha Wildner */
132*479ab7f0SSascha Wildner static ssize_t
rarpsend(struct iodesc * d,void * pkt,size_t len)133*479ab7f0SSascha Wildner rarpsend(struct iodesc *d, void *pkt, size_t len)
134*479ab7f0SSascha Wildner {
135*479ab7f0SSascha Wildner
136*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
137*479ab7f0SSascha Wildner if (debug)
138*479ab7f0SSascha Wildner printf("rarpsend: called\n");
139*479ab7f0SSascha Wildner #endif
140*479ab7f0SSascha Wildner
141*479ab7f0SSascha Wildner return (sendether(d, pkt, len, bcea, ETHERTYPE_REVARP));
142*479ab7f0SSascha Wildner }
143*479ab7f0SSascha Wildner
144*479ab7f0SSascha Wildner /*
145*479ab7f0SSascha Wildner * Returns 0 if this is the packet we're waiting for
146*479ab7f0SSascha Wildner * else -1 (and errno == 0)
147*479ab7f0SSascha Wildner */
148*479ab7f0SSascha Wildner static ssize_t
rarprecv(struct iodesc * d,void * pkt,size_t len,time_t tleft)149*479ab7f0SSascha Wildner rarprecv(struct iodesc *d, void *pkt, size_t len, time_t tleft)
150*479ab7f0SSascha Wildner {
151*479ab7f0SSascha Wildner ssize_t n;
152*479ab7f0SSascha Wildner struct ether_arp *ap;
153*479ab7f0SSascha Wildner u_int16_t etype; /* host order */
154*479ab7f0SSascha Wildner
155*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
156*479ab7f0SSascha Wildner if (debug)
157*479ab7f0SSascha Wildner printf("rarprecv: ");
158*479ab7f0SSascha Wildner #endif
159*479ab7f0SSascha Wildner
160*479ab7f0SSascha Wildner n = readether(d, pkt, len, tleft, &etype);
161*479ab7f0SSascha Wildner errno = 0; /* XXX */
162*479ab7f0SSascha Wildner if (n == -1 || n < sizeof(struct ether_arp)) {
163*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
164*479ab7f0SSascha Wildner if (debug)
165*479ab7f0SSascha Wildner printf("bad len=%d\n", n);
166*479ab7f0SSascha Wildner #endif
167*479ab7f0SSascha Wildner return (-1);
168*479ab7f0SSascha Wildner }
169*479ab7f0SSascha Wildner
170*479ab7f0SSascha Wildner if (etype != ETHERTYPE_REVARP) {
171*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
172*479ab7f0SSascha Wildner if (debug)
173*479ab7f0SSascha Wildner printf("bad type=0x%x\n", etype);
174*479ab7f0SSascha Wildner #endif
175*479ab7f0SSascha Wildner return (-1);
176*479ab7f0SSascha Wildner }
177*479ab7f0SSascha Wildner
178*479ab7f0SSascha Wildner ap = (struct ether_arp *)pkt;
179*479ab7f0SSascha Wildner if (ap->arp_hrd != htons(ARPHRD_ETHER) ||
180*479ab7f0SSascha Wildner ap->arp_pro != htons(ETHERTYPE_IP) ||
181*479ab7f0SSascha Wildner ap->arp_hln != sizeof(ap->arp_sha) ||
182*479ab7f0SSascha Wildner ap->arp_pln != sizeof(ap->arp_spa) )
183*479ab7f0SSascha Wildner {
184*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
185*479ab7f0SSascha Wildner if (debug)
186*479ab7f0SSascha Wildner printf("bad hrd/pro/hln/pln\n");
187*479ab7f0SSascha Wildner #endif
188*479ab7f0SSascha Wildner return (-1);
189*479ab7f0SSascha Wildner }
190*479ab7f0SSascha Wildner
191*479ab7f0SSascha Wildner if (ap->arp_op != htons(ARPOP_REVREPLY)) {
192*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
193*479ab7f0SSascha Wildner if (debug)
194*479ab7f0SSascha Wildner printf("bad op=0x%x\n", ntohs(ap->arp_op));
195*479ab7f0SSascha Wildner #endif
196*479ab7f0SSascha Wildner return (-1);
197*479ab7f0SSascha Wildner }
198*479ab7f0SSascha Wildner
199*479ab7f0SSascha Wildner /* Is the reply for our Ethernet address? */
200*479ab7f0SSascha Wildner if (bcmp(ap->arp_tha, d->myea, 6)) {
201*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
202*479ab7f0SSascha Wildner if (debug)
203*479ab7f0SSascha Wildner printf("unwanted address\n");
204*479ab7f0SSascha Wildner #endif
205*479ab7f0SSascha Wildner return (-1);
206*479ab7f0SSascha Wildner }
207*479ab7f0SSascha Wildner
208*479ab7f0SSascha Wildner /* We have our answer. */
209*479ab7f0SSascha Wildner #ifdef RARP_DEBUG
210*479ab7f0SSascha Wildner if (debug)
211*479ab7f0SSascha Wildner printf("got it\n");
212*479ab7f0SSascha Wildner #endif
213*479ab7f0SSascha Wildner return (n);
214*479ab7f0SSascha Wildner }
215