Annotation of sys/lib/libsa/rarp.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: rarp.c,v 1.10 2003/08/11 06:23:09 deraadt Exp $ */
2: /* $NetBSD: rarp.c,v 1.13 1996/10/13 02:29:05 christos Exp $ */
3:
4: /*
5: * Copyright (c) 1992 Regents of the University of California.
6: * All rights reserved.
7: *
8: * This software was developed by the Computer Systems Engineering group
9: * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
10: * contributed to Berkeley.
11: *
12: * Redistribution and use in source and binary forms, with or without
13: * modification, are permitted provided that the following conditions
14: * are met:
15: * 1. Redistributions of source code must retain the above copyright
16: * notice, this list of conditions and the following disclaimer.
17: * 2. Redistributions in binary form must reproduce the above copyright
18: * notice, this list of conditions and the following disclaimer in the
19: * documentation and/or other materials provided with the distribution.
20: * 3. All advertising materials mentioning features or use of this software
21: * must display the following acknowledgement:
22: * This product includes software developed by the University of
23: * California, Lawrence Berkeley Laboratory and its contributors.
24: * 4. Neither the name of the University nor the names of its contributors
25: * may be used to endorse or promote products derived from this software
26: * without specific prior written permission.
27: *
28: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38: * SUCH DAMAGE.
39: *
40: * @(#) Header: arp.c,v 1.5 93/07/15 05:52:26 leres Exp (LBL)
41: */
42: #include <sys/param.h>
43: #include <sys/socket.h>
44: #include <net/if.h>
45: #include <netinet/in.h>
46:
47: #include <netinet/if_ether.h>
48: #include <netinet/in_systm.h>
49:
50: #include "stand.h"
51: #include "net.h"
52: #include "netif.h"
53:
54: static ssize_t rarpsend(struct iodesc *, void *, size_t);
55: static ssize_t rarprecv(struct iodesc *, void *, size_t, time_t);
56:
57: /*
58: * Ethernet (Reverse) Address Resolution Protocol (see RFC 903, and 826).
59: */
60: int
61: rarp_getipaddress(int sock)
62: {
63: struct iodesc *d;
64: struct ether_arp *ap;
65: struct {
66: u_char header[ETHER_SIZE];
67: struct {
68: struct ether_arp arp;
69: u_char pad[18]; /* 60 - sizeof(arp) */
70: } data;
71: } wbuf;
72: struct {
73: u_char header[ETHER_SIZE];
74: struct {
75: struct ether_arp arp;
76: u_char pad[24]; /* extra space */
77: } data;
78: } rbuf;
79:
80: #ifdef RARP_DEBUG
81: if (debug)
82: printf("rarp: socket=%d\n", sock);
83: #endif
84: if (!(d = socktodesc(sock))) {
85: printf("rarp: bad socket. %d\n", sock);
86: return (-1);
87: }
88: #ifdef RARP_DEBUG
89: if (debug)
90: printf("rarp: d=%x\n", (u_int)d);
91: #endif
92:
93: bzero((char *)&wbuf.data, sizeof(wbuf.data));
94: ap = &wbuf.data.arp;
95: ap->arp_hrd = htons(ARPHRD_ETHER);
96: ap->arp_pro = htons(ETHERTYPE_IP);
97: ap->arp_hln = sizeof(ap->arp_sha); /* hardware address length */
98: ap->arp_pln = sizeof(ap->arp_spa); /* protocol address length */
99: ap->arp_op = htons(ARPOP_REVREQUEST);
100: bcopy(d->myea, ap->arp_sha, 6);
101: bcopy(d->myea, ap->arp_tha, 6);
102:
103: if (sendrecv(d,
104: rarpsend, &wbuf.data, sizeof(wbuf.data),
105: rarprecv, &rbuf.data, sizeof(rbuf.data)) < 0)
106: {
107: printf("No response for RARP request\n");
108: return (-1);
109: }
110:
111: ap = &rbuf.data.arp;
112: bcopy(ap->arp_tpa, (char *)&myip, sizeof(myip));
113: #if 0
114: /* XXX - Can NOT assume this is our root server! */
115: bcopy(ap->arp_spa, (char *)&rootip, sizeof(rootip));
116: #endif
117:
118: /* Compute our "natural" netmask. */
119: if (IN_CLASSA(myip.s_addr))
120: netmask = IN_CLASSA_NET;
121: else if (IN_CLASSB(myip.s_addr))
122: netmask = IN_CLASSB_NET;
123: else
124: netmask = IN_CLASSC_NET;
125:
126: d->myip = myip;
127: return (0);
128: }
129:
130: /*
131: * Broadcast a RARP request (i.e. who knows who I am)
132: */
133: static ssize_t
134: rarpsend(struct iodesc *d, void *pkt, size_t len)
135: {
136:
137: #ifdef RARP_DEBUG
138: if (debug)
139: printf("rarpsend: called\n");
140: #endif
141:
142: return (sendether(d, pkt, len, bcea, ETHERTYPE_REVARP));
143: }
144:
145: /*
146: * Returns 0 if this is the packet we're waiting for
147: * else -1 (and errno == 0)
148: */
149: static ssize_t
150: rarprecv(struct iodesc *d, void *pkt, size_t len, time_t tleft)
151: {
152: ssize_t n;
153: struct ether_arp *ap;
154: u_int16_t etype; /* host order */
155:
156: #ifdef RARP_DEBUG
157: if (debug)
158: printf("rarprecv: ");
159: #endif
160:
161: n = readether(d, pkt, len, tleft, &etype);
162: errno = 0; /* XXX */
163: if (n < 0 || (size_t)n < sizeof(struct ether_arp)) {
164: #ifdef RARP_DEBUG
165: if (debug)
166: printf("bad len=%d\n", n);
167: #endif
168: return (-1);
169: }
170:
171: if (etype != ETHERTYPE_REVARP) {
172: #ifdef RARP_DEBUG
173: if (debug)
174: printf("bad type=0x%x\n", etype);
175: #endif
176: return (-1);
177: }
178:
179: ap = (struct ether_arp *)pkt;
180: if (ap->arp_hrd != htons(ARPHRD_ETHER) ||
181: ap->arp_pro != htons(ETHERTYPE_IP) ||
182: ap->arp_hln != sizeof(ap->arp_sha) ||
183: ap->arp_pln != sizeof(ap->arp_spa) )
184: {
185: #ifdef RARP_DEBUG
186: if (debug)
187: printf("bad hrd/pro/hln/pln\n");
188: #endif
189: return (-1);
190: }
191:
192: if (ap->arp_op != htons(ARPOP_REVREPLY)) {
193: #ifdef RARP_DEBUG
194: if (debug)
195: printf("bad op=0x%x\n", ntohs(ap->arp_op));
196: #endif
197: return (-1);
198: }
199:
200: /* Is the reply for our Ethernet address? */
201: if (bcmp(ap->arp_tha, d->myea, 6)) {
202: #ifdef RARP_DEBUG
203: if (debug)
204: printf("unwanted address\n");
205: #endif
206: return (-1);
207: }
208:
209: /* We have our answer. */
210: #ifdef RARP_DEBUG
211: if (debug)
212: printf("got it\n");
213: #endif
214: return (n);
215: }
CVSweb
![[BACK]](/icons/back.gif){kind=icon}
Return to rarp.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / sys / lib / libsa