bootp.c revision 1.12
1 /* $NetBSD: bootp.c,v 1.12 1997/09/06 13:55:56 drochner Exp $ */ 2 3 /* 4 * Copyright (c) 1992 Regents of the University of California. 5 * All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the University of 22 * California, Lawrence Berkeley Laboratory and its contributors. 23 * 4. Neither the name of the University nor the names of its contributors 24 * may be used to endorse or promote products derived from this software 25 * without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 28 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * @(#) Header: bootp.c,v 1.4 93/09/11 03:13:51 leres Exp (LBL) 40 */ 41 42 #include <sys/types.h> 43 #include <netinet/in.h> 44 #include <netinet/in_systm.h> 45 46 #ifdef _STANDALONE 47 #include <lib/libkern/libkern.h> 48 #else 49 #include <string.h> 50 #endif 51 52 #include "stand.h" 53 #include "net.h" 54 #include "netif.h" 55 #include "bootp.h" 56 57 static n_long nmask, smask; 58 59 static time_t bot; 60 61 static char vm_rfc1048[4] = VM_RFC1048; 62 #ifdef BOOTP_VEND_CMU 63 static char vm_cmu[4] = VM_CMU; 64 #endif 65 66 /* Local forwards */ 67 static ssize_t bootpsend __P((struct iodesc *, void *, size_t)); 68 static ssize_t bootprecv __P((struct iodesc *, void *, size_t, time_t)); 69 static int vend_rfc1048 __P((u_char *, u_int)); 70 #ifdef BOOTP_VEND_CMU 71 static void vend_cmu __P((u_char *)); 72 #endif 73 74 #ifdef SUPPORT_DHCP 75 static char expected_dhcpmsgtype = -1, dhcp_ok; 76 struct in_addr dhcp_serverip; 77 #endif 78 79 /* Fetch required bootp infomation */ 80 void 81 bootp(sock) 82 int sock; 83 { 84 struct iodesc *d; 85 register struct bootp *bp; 86 struct { 87 u_char header[HEADER_SIZE]; 88 struct bootp wbootp; 89 } wbuf; 90 struct { 91 u_char header[HEADER_SIZE]; 92 struct bootp rbootp; 93 } rbuf; 94 95 #ifdef BOOTP_DEBUG 96 if (debug) 97 printf("bootp: socket=%d\n", sock); 98 #endif 99 if (!bot) 100 bot = getsecs(); 101 102 if (!(d = socktodesc(sock))) { 103 printf("bootp: bad socket. %d\n", sock); 104 return; 105 } 106 #ifdef BOOTP_DEBUG 107 if (debug) 108 printf("bootp: d=%lx\n", (long)d); 109 #endif 110 111 bp = &wbuf.wbootp; 112 bzero(bp, sizeof(*bp)); 113 114 bp->bp_op = BOOTREQUEST; 115 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */ 116 bp->bp_hlen = 6; 117 bp->bp_xid = htonl(d->xid); 118 MACPY(d->myea, bp->bp_chaddr); 119 strncpy(bp->bp_file, bootfile, sizeof(bp->bp_file)); 120 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)); 121 #ifdef SUPPORT_DHCP 122 bp->bp_vend[4] = TAG_DHCP_MSGTYPE; 123 bp->bp_vend[5] = 1; 124 bp->bp_vend[6] = DHCPDISCOVER; 125 bp->bp_vend[7] = TAG_END; 126 #else 127 bp->bp_vend[4] = TAG_END; 128 #endif 129 130 d->myip = myip; 131 d->myport = htons(IPPORT_BOOTPC); 132 d->destip.s_addr = INADDR_BROADCAST; 133 d->destport = htons(IPPORT_BOOTPS); 134 135 #ifdef SUPPORT_DHCP 136 expected_dhcpmsgtype = DHCPOFFER; 137 dhcp_ok = 0; 138 #endif 139 140 if(sendrecv(d, 141 bootpsend, bp, sizeof(*bp), 142 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 143 == -1) { 144 printf("bootp: no reply\n"); 145 return; 146 } 147 148 #ifdef SUPPORT_DHCP 149 if(dhcp_ok) { 150 u_int32_t leasetime; 151 bp->bp_vend[6] = DHCPREQUEST; 152 bp->bp_vend[7] = TAG_REQ_ADDR; 153 bp->bp_vend[8] = 4; 154 bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4); 155 bp->bp_vend[13] = TAG_SERVERID; 156 bp->bp_vend[14] = 4; 157 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4); 158 bp->bp_vend[19] = TAG_LEASETIME; 159 bp->bp_vend[20] = 4; 160 leasetime = htonl(300); 161 bcopy(&leasetime, &bp->bp_vend[21], 4); 162 bp->bp_vend[25] = TAG_END; 163 164 expected_dhcpmsgtype = DHCPACK; 165 166 if(sendrecv(d, 167 bootpsend, bp, sizeof(*bp), 168 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 169 == -1) { 170 printf("DHCPREQUEST failed\n"); 171 return; 172 } 173 } 174 #endif 175 176 myip = d->myip = rbuf.rbootp.bp_yiaddr; 177 if(rootip.s_addr == INADDR_ANY) rootip = rbuf.rbootp.bp_siaddr; 178 bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile)); 179 bootfile[sizeof(bootfile) - 1] = '\0'; 180 181 if (IN_CLASSA(myip.s_addr)) 182 nmask = IN_CLASSA_NET; 183 else if (IN_CLASSB(myip.s_addr)) 184 nmask = IN_CLASSB_NET; 185 else 186 nmask = IN_CLASSC_NET; 187 #ifdef BOOTP_DEBUG 188 if (debug) 189 printf("'native netmask' is %s\n", intoa(nmask)); 190 #endif 191 192 /* Check subnet mask against net mask; toss if bogus */ 193 if ((nmask & smask) != nmask) { 194 #ifdef BOOTP_DEBUG 195 if (debug) 196 printf("subnet mask (%s) bad\n", intoa(smask)); 197 #endif 198 smask = 0; 199 } 200 201 /* Get subnet (or natural net) mask */ 202 netmask = nmask; 203 if (smask) 204 netmask = smask; 205 #ifdef BOOTP_DEBUG 206 if (debug) 207 printf("mask: %s\n", intoa(netmask)); 208 #endif 209 210 /* We need a gateway if root is on a different net */ 211 if (!SAMENET(myip, rootip, netmask)) { 212 #ifdef BOOTP_DEBUG 213 if (debug) 214 printf("need gateway for root ip\n"); 215 #endif 216 } 217 218 /* Toss gateway if on a different net */ 219 if (!SAMENET(myip, gateip, netmask)) { 220 #ifdef BOOTP_DEBUG 221 if (debug) 222 printf("gateway ip (%s) bad\n", inet_ntoa(gateip)); 223 #endif 224 gateip.s_addr = 0; 225 } 226 227 /* Bump xid so next request will be unique. */ 228 ++d->xid; 229 } 230 231 /* Transmit a bootp request */ 232 static ssize_t 233 bootpsend(d, pkt, len) 234 register struct iodesc *d; 235 register void *pkt; 236 register size_t len; 237 { 238 register struct bootp *bp; 239 240 #ifdef BOOTP_DEBUG 241 if (debug) 242 printf("bootpsend: d=%lx called.\n", (long)d); 243 #endif 244 245 bp = pkt; 246 bp->bp_secs = htons((u_short)(getsecs() - bot)); 247 248 #ifdef BOOTP_DEBUG 249 if (debug) 250 printf("bootpsend: calling sendudp\n"); 251 #endif 252 253 return (sendudp(d, pkt, len)); 254 } 255 256 static ssize_t 257 bootprecv(d, pkt, len, tleft) 258 register struct iodesc *d; 259 register void *pkt; 260 register size_t len; 261 time_t tleft; 262 { 263 register ssize_t n; 264 register struct bootp *bp; 265 266 #ifdef BOOTP_DEBUGx 267 if (debug) 268 printf("bootp_recvoffer: called\n"); 269 #endif 270 271 n = readudp(d, pkt, len, tleft); 272 if (n == -1 || n < sizeof(struct bootp) - BOOTP_VENDSIZE) 273 goto bad; 274 275 bp = (struct bootp *)pkt; 276 277 #ifdef BOOTP_DEBUG 278 if (debug) 279 printf("bootprecv: checked. bp = 0x%lx, n = %d\n", 280 (long)bp, (int)n); 281 #endif 282 if (bp->bp_xid != htonl(d->xid)) { 283 #ifdef BOOTP_DEBUG 284 if (debug) { 285 printf("bootprecv: expected xid 0x%lx, got 0x%x\n", 286 d->xid, ntohl(bp->bp_xid)); 287 } 288 #endif 289 goto bad; 290 } 291 292 #ifdef BOOTP_DEBUG 293 if (debug) 294 printf("bootprecv: got one!\n"); 295 #endif 296 297 /* Suck out vendor info */ 298 if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) { 299 if(vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0) 300 goto bad; 301 } 302 #ifdef BOOTP_VEND_CMU 303 else if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0) 304 vend_cmu(bp->bp_vend); 305 #endif 306 else 307 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend); 308 309 return(n); 310 bad: 311 errno = 0; 312 return (-1); 313 } 314 315 static int 316 vend_rfc1048(cp, len) 317 register u_char *cp; 318 u_int len; 319 { 320 register u_char *ep; 321 register int size; 322 register u_char tag; 323 324 #ifdef BOOTP_DEBUG 325 if (debug) 326 printf("vend_rfc1048 bootp info. len=%d\n", len); 327 #endif 328 ep = cp + len; 329 330 /* Step over magic cookie */ 331 cp += sizeof(int); 332 333 while (cp < ep) { 334 tag = *cp++; 335 size = *cp++; 336 if (tag == TAG_END) 337 break; 338 339 if (tag == TAG_SUBNET_MASK) { 340 bcopy(cp, &smask, sizeof(smask)); 341 } 342 if (tag == TAG_GATEWAY) { 343 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr)); 344 } 345 if (tag == TAG_SWAPSERVER) { 346 /* let it override bp_siaddr */ 347 bcopy(cp, &rootip.s_addr, sizeof(swapip.s_addr)); 348 } 349 if (tag == TAG_ROOTPATH) { 350 strncpy(rootpath, (char *)cp, sizeof(rootpath)); 351 rootpath[size] = '\0'; 352 } 353 if (tag == TAG_HOSTNAME) { 354 strncpy(hostname, (char *)cp, sizeof(hostname)); 355 hostname[size] = '\0'; 356 } 357 #ifdef SUPPORT_DHCP 358 if (tag == TAG_DHCP_MSGTYPE) { 359 if(*cp != expected_dhcpmsgtype) 360 return(-1); 361 dhcp_ok = 1; 362 } 363 if (tag == TAG_SERVERID) { 364 bcopy(cp, &dhcp_serverip.s_addr, 365 sizeof(dhcp_serverip.s_addr)); 366 } 367 #endif 368 cp += size; 369 } 370 return(0); 371 } 372 373 #ifdef BOOTP_VEND_CMU 374 static void 375 vend_cmu(cp) 376 u_char *cp; 377 { 378 register struct cmu_vend *vp; 379 380 #ifdef BOOTP_DEBUG 381 if (debug) 382 printf("vend_cmu bootp info.\n"); 383 #endif 384 vp = (struct cmu_vend *)cp; 385 386 if (vp->v_smask.s_addr != 0) { 387 smask = vp->v_smask.s_addr; 388 } 389 if (vp->v_dgate.s_addr != 0) { 390 gateip = vp->v_dgate; 391 } 392 } 393 #endif 394
Indexes created Tue Sep 30 11:09:46 GMT 2025