bootp.c revision 1.16
1 /* $NetBSD: bootp.c,v 1.16 1999/02/12 10:56:18 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 struct in_addr servip; 58 #ifdef SUPPORT_LINUX 59 char linuxcmdline[256]; 60 #ifndef TAG_LINUX_CMDLINE 61 #define TAG_LINUX_CMDLINE 123 62 #endif 63 #endif 64 65 static n_long nmask, smask; 66 67 static time_t bot; 68 69 static char vm_rfc1048[4] = VM_RFC1048; 70 #ifdef BOOTP_VEND_CMU 71 static char vm_cmu[4] = VM_CMU; 72 #endif 73 74 /* Local forwards */ 75 static ssize_t bootpsend __P((struct iodesc *, void *, size_t)); 76 static ssize_t bootprecv __P((struct iodesc *, void *, size_t, time_t)); 77 static int vend_rfc1048 __P((u_char *, u_int)); 78 #ifdef BOOTP_VEND_CMU 79 static void vend_cmu __P((u_char *)); 80 #endif 81 82 #ifdef SUPPORT_DHCP 83 static char expected_dhcpmsgtype = -1, dhcp_ok; 84 struct in_addr dhcp_serverip; 85 #endif 86 87 /* Fetch required bootp infomation */ 88 void 89 bootp(sock) 90 int sock; 91 { 92 struct iodesc *d; 93 register struct bootp *bp; 94 struct { 95 u_char header[HEADER_SIZE]; 96 struct bootp wbootp; 97 } wbuf; 98 struct { 99 u_char header[HEADER_SIZE]; 100 struct bootp rbootp; 101 } rbuf; 102 103 #ifdef BOOTP_DEBUG 104 if (debug) 105 printf("bootp: socket=%d\n", sock); 106 #endif 107 if (!bot) 108 bot = getsecs(); 109 110 if (!(d = socktodesc(sock))) { 111 printf("bootp: bad socket. %d\n", sock); 112 return; 113 } 114 #ifdef BOOTP_DEBUG 115 if (debug) 116 printf("bootp: d=%lx\n", (long)d); 117 #endif 118 119 bp = &wbuf.wbootp; 120 bzero(bp, sizeof(*bp)); 121 122 bp->bp_op = BOOTREQUEST; 123 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */ 124 bp->bp_hlen = 6; 125 bp->bp_xid = htonl(d->xid); 126 MACPY(d->myea, bp->bp_chaddr); 127 strncpy(bp->bp_file, bootfile, sizeof(bp->bp_file)); 128 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)); 129 #ifdef SUPPORT_DHCP 130 bp->bp_vend[4] = TAG_DHCP_MSGTYPE; 131 bp->bp_vend[5] = 1; 132 bp->bp_vend[6] = DHCPDISCOVER; 133 bp->bp_vend[7] = TAG_END; 134 #else 135 bp->bp_vend[4] = TAG_END; 136 #endif 137 138 d->myip.s_addr = INADDR_ANY; 139 d->myport = htons(IPPORT_BOOTPC); 140 d->destip.s_addr = INADDR_BROADCAST; 141 d->destport = htons(IPPORT_BOOTPS); 142 143 #ifdef SUPPORT_DHCP 144 expected_dhcpmsgtype = DHCPOFFER; 145 dhcp_ok = 0; 146 #endif 147 148 if (sendrecv(d, 149 bootpsend, bp, sizeof(*bp), 150 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 151 == -1) { 152 printf("bootp: no reply\n"); 153 return; 154 } 155 156 #ifdef SUPPORT_DHCP 157 if (dhcp_ok) { 158 u_int32_t leasetime; 159 bp->bp_vend[6] = DHCPREQUEST; 160 bp->bp_vend[7] = TAG_REQ_ADDR; 161 bp->bp_vend[8] = 4; 162 bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4); 163 bp->bp_vend[13] = TAG_SERVERID; 164 bp->bp_vend[14] = 4; 165 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4); 166 bp->bp_vend[19] = TAG_LEASETIME; 167 bp->bp_vend[20] = 4; 168 leasetime = htonl(300); 169 bcopy(&leasetime, &bp->bp_vend[21], 4); 170 bp->bp_vend[25] = TAG_END; 171 172 expected_dhcpmsgtype = DHCPACK; 173 174 if (sendrecv(d, 175 bootpsend, bp, sizeof(*bp), 176 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 177 == -1) { 178 printf("DHCPREQUEST failed\n"); 179 return; 180 } 181 } 182 #endif 183 184 myip = d->myip = rbuf.rbootp.bp_yiaddr; 185 servip = rbuf.rbootp.bp_siaddr; 186 if (rootip.s_addr == INADDR_ANY) 187 rootip = servip; 188 bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile)); 189 bootfile[sizeof(bootfile) - 1] = '\0'; 190 191 if (IN_CLASSA(myip.s_addr)) 192 nmask = IN_CLASSA_NET; 193 else if (IN_CLASSB(myip.s_addr)) 194 nmask = IN_CLASSB_NET; 195 else 196 nmask = IN_CLASSC_NET; 197 #ifdef BOOTP_DEBUG 198 if (debug) 199 printf("'native netmask' is %s\n", intoa(nmask)); 200 #endif 201 202 /* Check subnet mask against net mask; toss if bogus */ 203 if ((nmask & smask) != nmask) { 204 #ifdef BOOTP_DEBUG 205 if (debug) 206 printf("subnet mask (%s) bad\n", intoa(smask)); 207 #endif 208 smask = 0; 209 } 210 211 /* Get subnet (or natural net) mask */ 212 netmask = nmask; 213 if (smask) 214 netmask = smask; 215 #ifdef BOOTP_DEBUG 216 if (debug) 217 printf("mask: %s\n", intoa(netmask)); 218 #endif 219 220 /* We need a gateway if root is on a different net */ 221 if (!SAMENET(myip, rootip, netmask)) { 222 #ifdef BOOTP_DEBUG 223 if (debug) 224 printf("need gateway for root ip\n"); 225 #endif 226 } 227 228 /* Toss gateway if on a different net */ 229 if (!SAMENET(myip, gateip, netmask)) { 230 #ifdef BOOTP_DEBUG 231 if (debug) 232 printf("gateway ip (%s) bad\n", inet_ntoa(gateip)); 233 #endif 234 gateip.s_addr = 0; 235 } 236 237 /* Bump xid so next request will be unique. */ 238 ++d->xid; 239 } 240 241 /* Transmit a bootp request */ 242 static ssize_t 243 bootpsend(d, pkt, len) 244 register struct iodesc *d; 245 register void *pkt; 246 register size_t len; 247 { 248 register struct bootp *bp; 249 250 #ifdef BOOTP_DEBUG 251 if (debug) 252 printf("bootpsend: d=%lx called.\n", (long)d); 253 #endif 254 255 bp = pkt; 256 bp->bp_secs = htons((u_short)(getsecs() - bot)); 257 258 #ifdef BOOTP_DEBUG 259 if (debug) 260 printf("bootpsend: calling sendudp\n"); 261 #endif 262 263 return (sendudp(d, pkt, len)); 264 } 265 266 static ssize_t 267 bootprecv(d, pkt, len, tleft) 268 register struct iodesc *d; 269 register void *pkt; 270 register size_t len; 271 time_t tleft; 272 { 273 register ssize_t n; 274 register struct bootp *bp; 275 276 #ifdef BOOTP_DEBUGx 277 if (debug) 278 printf("bootp_recvoffer: called\n"); 279 #endif 280 281 n = readudp(d, pkt, len, tleft); 282 if (n == -1 || n < sizeof(struct bootp) - BOOTP_VENDSIZE) 283 goto bad; 284 285 bp = (struct bootp *)pkt; 286 287 #ifdef BOOTP_DEBUG 288 if (debug) 289 printf("bootprecv: checked. bp = 0x%lx, n = %d\n", 290 (long)bp, (int)n); 291 #endif 292 if (bp->bp_xid != htonl(d->xid)) { 293 #ifdef BOOTP_DEBUG 294 if (debug) { 295 printf("bootprecv: expected xid 0x%lx, got 0x%x\n", 296 d->xid, ntohl(bp->bp_xid)); 297 } 298 #endif 299 goto bad; 300 } 301 302 /* protect against bogus addresses sent by DHCP servers */ 303 if (bp->bp_yiaddr.s_addr == INADDR_ANY || 304 bp->bp_yiaddr.s_addr == INADDR_BROADCAST) 305 goto bad; 306 307 #ifdef BOOTP_DEBUG 308 if (debug) 309 printf("bootprecv: got one!\n"); 310 #endif 311 312 /* Suck out vendor info */ 313 if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) { 314 if (vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0) 315 goto bad; 316 } 317 #ifdef BOOTP_VEND_CMU 318 else if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0) 319 vend_cmu(bp->bp_vend); 320 #endif 321 else 322 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend); 323 324 return (n); 325 bad: 326 errno = 0; 327 return (-1); 328 } 329 330 static int 331 vend_rfc1048(cp, len) 332 register u_char *cp; 333 u_int len; 334 { 335 register u_char *ep; 336 register int size; 337 register u_char tag; 338 339 #ifdef BOOTP_DEBUG 340 if (debug) 341 printf("vend_rfc1048 bootp info. len=%d\n", len); 342 #endif 343 ep = cp + len; 344 345 /* Step over magic cookie */ 346 cp += sizeof(int); 347 348 while (cp < ep) { 349 tag = *cp++; 350 size = *cp++; 351 if (tag == TAG_END) 352 break; 353 354 if (tag == TAG_SUBNET_MASK) { 355 bcopy(cp, &smask, sizeof(smask)); 356 } 357 if (tag == TAG_GATEWAY) { 358 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr)); 359 } 360 if (tag == TAG_SWAPSERVER) { 361 /* let it override bp_siaddr */ 362 bcopy(cp, &rootip.s_addr, sizeof(rootip.s_addr)); 363 } 364 if (tag == TAG_ROOTPATH) { 365 strncpy(rootpath, (char *)cp, sizeof(rootpath)); 366 rootpath[size] = '\0'; 367 } 368 if (tag == TAG_HOSTNAME) { 369 strncpy(hostname, (char *)cp, sizeof(hostname)); 370 hostname[size] = '\0'; 371 } 372 #ifdef SUPPORT_DHCP 373 if (tag == TAG_DHCP_MSGTYPE) { 374 if (*cp != expected_dhcpmsgtype) 375 return (-1); 376 dhcp_ok = 1; 377 } 378 if (tag == TAG_SERVERID) { 379 bcopy(cp, &dhcp_serverip.s_addr, 380 sizeof(dhcp_serverip.s_addr)); 381 } 382 #endif 383 #ifdef SUPPORT_LINUX 384 if (tag == TAG_LINUX_CMDLINE) { 385 strncpy(linuxcmdline, (char *)cp, sizeof(linuxcmdline)); 386 linuxcmdline[size] = '\0'; 387 } 388 #endif 389 cp += size; 390 } 391 return (0); 392 } 393 394 #ifdef BOOTP_VEND_CMU 395 static void 396 vend_cmu(cp) 397 u_char *cp; 398 { 399 register struct cmu_vend *vp; 400 401 #ifdef BOOTP_DEBUG 402 if (debug) 403 printf("vend_cmu bootp info.\n"); 404 #endif 405 vp = (struct cmu_vend *)cp; 406 407 if (vp->v_smask.s_addr != 0) { 408 smask = vp->v_smask.s_addr; 409 } 410 if (vp->v_dgate.s_addr != 0) { 411 gateip = vp->v_dgate; 412 } 413 } 414 #endif 415
Indexes created Mon Sep 29 21:09:56 GMT 2025