1 /**	$MirOS: src/sys/lib/libsa/bootp.c,v 1.4 2009/01/03 17:37:49 tg Exp $ */
2 /*	$OpenBSD: bootp.c,v 1.12 2006/02/06 17:37:28 jmc Exp $	*/
3 /*	$NetBSD: bootp.c,v 1.10 1996/10/13 02:28:59 christos Exp $	*/
4 
5 /*
6  * Copyright (c) 1992 Regents of the University of California.
7  * All rights reserved.
8  *
9  * This software was developed by the Computer Systems Engineering group
10  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
11  * contributed to Berkeley.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. All advertising materials mentioning features or use of this software
22  *    must display the following acknowledgement:
23  *	This product includes software developed by the University of
24  *	California, Lawrence Berkeley Laboratory and its contributors.
25  * 4. Neither the name of the University nor the names of its contributors
26  *    may be used to endorse or promote products derived from this software
27  *    without specific prior written permission.
28  *
29  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
30  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
31  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
32  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
33  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
34  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
35  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
36  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
37  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
38  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
39  * SUCH DAMAGE.
40  *
41  * @(#) Header: bootp.c,v 1.4 93/09/11 03:13:51 leres Exp  (LBL)
42  */
43 
44 #include <sys/types.h>
45 #include <sys/socket.h>
46 #include <netinet/in.h>
47 #include <netinet/in_systm.h>
48 
49 #include "stand.h"
50 #include "net.h"
51 #include "netif.h"
52 #include "bootp.h"
53 
54 static n_long	nmask, smask;
55 
56 static time_t	bot;
57 
58 static	char vm_rfc1048[4] = VM_RFC1048;
59 static	char vm_cmu[4] = VM_CMU;
60 
61 /* Local forwards */
62 static	ssize_t bootpsend(struct iodesc *, void *, size_t);
63 static	ssize_t bootprecv(struct iodesc *, void *, size_t, time_t);
64 static	void vend_cmu(u_char *);
65 static	void vend_rfc1048(u_char *, u_int);
66 
67 /* Fetch required bootp information */
68 void
bootp(int sock)69 bootp(int sock)
70 {
71 	struct iodesc *d;
72 	struct bootp *bp;
73 	struct bootp_xbuf {
74 		u_char header[HEADER_SIZE];
75 		struct bootp xbootp;
76 	} *rbuf, *wbuf;
77 
78 #ifdef BOOTP_DEBUG
79 	if (debug)
80 		printf("bootp: socket=%d\n", sock);
81 #endif
82 	if (!bot)
83 		bot = getsecs();
84 
85 	if (!(d = socktodesc(sock))) {
86 		printf("bootp: bad socket. %d\n", sock);
87 		return;
88 	}
89 #ifdef BOOTP_DEBUG
90 	if (debug)
91 		printf("bootp: d=%x\n", (u_int)d);
92 #endif
93 
94 	rbuf = alloc(sizeof (struct bootp_xbuf));
95 	wbuf = alloc(sizeof (struct bootp_xbuf));
96 
97 	bp = &wbuf->xbootp;
98 	bzero(bp, sizeof(*bp));
99 
100 	bp->bp_op = BOOTREQUEST;
101 	bp->bp_htype = HTYPE_ETHERNET;	/* 10Mb Ethernet (48 bits) */
102 	bp->bp_hlen = 6;
103 	bp->bp_xid = htonl(d->xid);
104 	MACPY(d->myea, bp->bp_chaddr);
105 	bzero(bp->bp_file, sizeof(bp->bp_file));
106 	bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048));
107 
108 	d->myip = myip;
109 	d->myport = htons(IPPORT_BOOTPC);
110 	d->destip.s_addr = INADDR_BROADCAST;
111 	d->destport = htons(IPPORT_BOOTPS);
112 
113 	(void)sendrecv(d,
114 	    bootpsend, bp, sizeof(*bp),
115 	    bootprecv, &rbuf->xbootp, sizeof(rbuf->xbootp));
116 
117 	free(wbuf, sizeof (struct bootp_xbuf));
118 	free(rbuf, sizeof (struct bootp_xbuf));
119 
120 	/* Bump xid so next request will be unique. */
121 	++d->xid;
122 }
123 
124 /* Transmit a bootp request */
125 static ssize_t
bootpsend(struct iodesc * d,void * pkt,size_t len)126 bootpsend(struct iodesc *d, void *pkt, size_t len)
127 {
128 	struct bootp *bp;
129 
130 #ifdef BOOTP_DEBUG
131 	if (debug)
132 		printf("bootpsend: d=%x called.\n", (u_int)d);
133 #endif
134 
135 	bp = pkt;
136 	bp->bp_secs = htons((u_short)(getsecs() - bot));
137 
138 #ifdef BOOTP_DEBUG
139 	if (debug)
140 		printf("bootpsend: calling sendudp\n");
141 #endif
142 
143 	return (sendudp(d, pkt, len));
144 }
145 
146 /* Returns 0 if this is the packet we're waiting for else -1 (and errno == 0) */
147 static ssize_t
bootprecv(struct iodesc * d,void * pkt,size_t len,time_t tleft)148 bootprecv(struct iodesc *d, void *pkt, size_t len, time_t tleft)
149 {
150 	ssize_t n;
151 	struct bootp *bp;
152 
153 #ifdef BOOTP_DEBUG
154 	if (debug)
155 		printf("bootprecv: called\n");
156 #endif
157 
158 	n = readudp(d, pkt, len, tleft);
159 	if (n < 0 || (size_t)n < sizeof(struct bootp))
160 		goto bad;
161 
162 	bp = (struct bootp *)pkt;
163 
164 #ifdef BOOTP_DEBUG
165 	if (debug)
166 		printf("bootprecv: checked.  bp = 0x%x, n = %d\n",
167 		    (unsigned)bp, n);
168 #endif
169 	if (bp->bp_xid != htonl(d->xid)) {
170 #ifdef BOOTP_DEBUG
171 		if (debug) {
172 			printf("bootprecv: expected xid 0x%lx, got 0x%lx\n",
173 			    d->xid, ntohl(bp->bp_xid));
174 		}
175 #endif
176 		goto bad;
177 	}
178 
179 #ifdef BOOTP_DEBUG
180 	if (debug)
181 		printf("bootprecv: got one!\n");
182 #endif
183 
184 	/* Pick up our ip address (and natural netmask) */
185 	myip = d->myip = bp->bp_yiaddr;
186 #ifdef BOOTP_DEBUG
187 	if (debug)
188 		printf("our ip address is %s\n", inet_ntoa(d->myip));
189 #endif
190 	if (IN_CLASSA(d->myip.s_addr))
191 		nmask = IN_CLASSA_NET;
192 	else if (IN_CLASSB(d->myip.s_addr))
193 		nmask = IN_CLASSB_NET;
194 	else
195 		nmask = IN_CLASSC_NET;
196 #ifdef BOOTP_DEBUG
197 	if (debug)
198 		printf("'native netmask' is %s\n", intoa(nmask));
199 #endif
200 
201 	/* Pick up root or swap server address and file spec. */
202 	if (bp->bp_siaddr.s_addr != 0)
203 		rootip = bp->bp_siaddr;
204 	if (bp->bp_file[0] != '\0') {
205 		strncpy(bootfile, (char *)bp->bp_file, sizeof(bootfile));
206 		bootfile[sizeof(bootfile) - 1] = '\0';
207 	}
208 
209 	/* Suck out vendor info */
210 	if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0)
211 		vend_cmu(bp->bp_vend);
212 	else if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0)
213 		vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend));
214 	else
215 		printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend);
216 
217 	/* Check subnet mask against net mask; toss if bogus */
218 	if ((nmask & smask) != nmask) {
219 #ifdef BOOTP_DEBUG
220 		if (debug)
221 			printf("subnet mask (%s) bad\n", intoa(smask));
222 #endif
223 		smask = 0;
224 	}
225 
226 	/* Get subnet (or natural net) mask */
227 	netmask = nmask;
228 	if (smask)
229 		netmask = smask;
230 #ifdef BOOTP_DEBUG
231 	if (debug)
232 		printf("mask: %s\n", intoa(netmask));
233 #endif
234 
235 	/* We need a gateway if root or swap is on a different net */
236 	if (!SAMENET(d->myip, rootip, netmask)) {
237 #ifdef BOOTP_DEBUG
238 		if (debug)
239 			printf("need gateway for root ip\n");
240 #endif
241 	}
242 
243 	if (!SAMENET(d->myip, swapip, netmask)) {
244 #ifdef BOOTP_DEBUG
245 		if (debug)
246 			printf("need gateway for swap ip\n");
247 #endif
248 	}
249 
250 	/* Toss gateway if on a different net */
251 	if (!SAMENET(d->myip, gateip, netmask)) {
252 #ifdef BOOTP_DEBUG
253 		if (debug)
254 			printf("gateway ip (%s) bad\n", inet_ntoa(gateip));
255 #endif
256 		gateip.s_addr = 0;
257 	}
258 
259 	return (n);
260 
261 bad:
262 	errno = 0;
263 	return (-1);
264 }
265 
266 static void
vend_cmu(u_char * cp)267 vend_cmu(u_char *cp)
268 {
269 	struct cmu_vend *vp;
270 
271 #ifdef BOOTP_DEBUG
272 	if (debug)
273 		printf("vend_cmu bootp info.\n");
274 #endif
275 	vp = (struct cmu_vend *)cp;
276 
277 	if (vp->v_smask.s_addr != 0)
278 		smask = vp->v_smask.s_addr;
279 	if (vp->v_dgate.s_addr != 0)
280 		gateip = vp->v_dgate;
281 }
282 
283 static void
vend_rfc1048(u_char * cp,u_int len)284 vend_rfc1048(u_char *cp, u_int len)
285 {
286 	u_char *ep;
287 	int size;
288 	u_char tag;
289 
290 #ifdef BOOTP_DEBUG
291 	if (debug)
292 		printf("vend_rfc1048 bootp info. len=%d\n", len);
293 #endif
294 	ep = cp + len;
295 
296 	/* Step over magic cookie */
297 	cp += sizeof(int);
298 
299 	while (cp < ep) {
300 		tag = *cp++;
301 		size = *cp++;
302 		if (tag == TAG_END)
303 			break;
304 
305 		if (tag == TAG_SUBNET_MASK)
306 			bcopy(cp, &smask, sizeof(smask));
307 		if (tag == TAG_GATEWAY)
308 			bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr));
309 		if (tag == TAG_SWAPSERVER)
310 			bcopy(cp, &swapip.s_addr, sizeof(swapip.s_addr));
311 		if (tag == TAG_DOMAIN_SERVER)
312 			bcopy(cp, &nameip.s_addr, sizeof(nameip.s_addr));
313 		if (tag == TAG_ROOTPATH) {
314 			strncpy(rootpath, (char *)cp, sizeof(rootpath));
315 			rootpath[size] = '\0';
316 		}
317 		if (tag == TAG_HOSTNAME) {
318 			strncpy(hostname, (char *)cp, sizeof(hostname));
319 			hostname[size] = '\0';
320 		}
321 		cp += size;
322 	}
323 }
324