bootp.c revision 1.30
1 /* $NetBSD: bootp.c,v 1.30 2007/10/01 13:15:06 martin 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/param.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 "bootp.h" 55 56 struct in_addr servip; 57 #ifdef SUPPORT_LINUX 58 char linuxcmdline[256]; 59 #ifndef TAG_LINUX_CMDLINE 60 #define TAG_LINUX_CMDLINE 123 61 #endif 62 #endif 63 64 static n_long nmask, smask; 65 66 static time_t bot; 67 68 static char vm_rfc1048[4] = VM_RFC1048; 69 #ifdef BOOTP_VEND_CMU 70 static char vm_cmu[4] = VM_CMU; 71 #endif 72 73 /* Local forwards */ 74 static ssize_t bootpsend __P((struct iodesc *, void *, size_t)); 75 static ssize_t bootprecv __P((struct iodesc *, void *, size_t, time_t)); 76 static int vend_rfc1048 __P((u_char *, u_int)); 77 #ifdef BOOTP_VEND_CMU 78 static void vend_cmu __P((u_char *)); 79 #endif 80 81 #ifdef SUPPORT_DHCP 82 static char expected_dhcpmsgtype = -1, dhcp_ok; 83 struct in_addr dhcp_serverip; 84 #endif 85 86 /* 87 * Boot programs can patch this at run-time to change the behavior 88 * of bootp/dhcp. 89 */ 90 int bootp_flags; 91 92 /* Fetch required bootp information */ 93 void 94 bootp(sock) 95 int sock; 96 { 97 struct iodesc *d; 98 struct bootp *bp; 99 struct { 100 u_char header[HEADER_SIZE]; 101 struct bootp wbootp; 102 } wbuf; 103 struct { 104 u_char header[HEADER_SIZE]; 105 struct bootp rbootp; 106 } rbuf; 107 #ifdef SUPPORT_DHCP 108 char vci[64]; 109 int vcilen; 110 #endif 111 112 #ifdef BOOTP_DEBUG 113 if (debug) 114 printf("bootp: socket=%d\n", sock); 115 #endif 116 if (!bot) 117 bot = getsecs(); 118 119 if (!(d = socktodesc(sock))) { 120 printf("bootp: bad socket. %d\n", sock); 121 return; 122 } 123 #ifdef BOOTP_DEBUG 124 if (debug) 125 printf("bootp: d=%lx\n", (long)d); 126 #endif 127 128 bp = &wbuf.wbootp; 129 bzero(bp, sizeof(*bp)); 130 131 bp->bp_op = BOOTREQUEST; 132 bp->bp_htype = 1; /* 10Mb Ethernet (48 bits) */ 133 bp->bp_hlen = 6; 134 bp->bp_xid = htonl(d->xid); 135 MACPY(d->myea, bp->bp_chaddr); 136 strncpy((char *)bp->bp_file, bootfile, sizeof(bp->bp_file)); 137 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)); 138 #ifdef SUPPORT_DHCP 139 bp->bp_vend[4] = TAG_DHCP_MSGTYPE; 140 bp->bp_vend[5] = 1; 141 bp->bp_vend[6] = DHCPDISCOVER; 142 /* 143 * Insert a NetBSD Vendor Class Identifier option. 144 */ 145 sprintf(vci, "NetBSD:%s:libsa", MACHINE); 146 vcilen = strlen(vci); 147 bp->bp_vend[7] = TAG_CLASSID; 148 bp->bp_vend[8] = vcilen; 149 bcopy(vci, &bp->bp_vend[9], vcilen); 150 bp->bp_vend[9 + vcilen] = TAG_END; 151 #else 152 bp->bp_vend[4] = TAG_END; 153 #endif 154 155 d->myip.s_addr = INADDR_ANY; 156 d->myport = htons(IPPORT_BOOTPC); 157 d->destip.s_addr = INADDR_BROADCAST; 158 d->destport = htons(IPPORT_BOOTPS); 159 160 #ifdef SUPPORT_DHCP 161 expected_dhcpmsgtype = DHCPOFFER; 162 dhcp_ok = 0; 163 #endif 164 165 if (sendrecv(d, 166 bootpsend, bp, sizeof(*bp), 167 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 168 == -1) { 169 printf("bootp: no reply\n"); 170 return; 171 } 172 173 #ifdef SUPPORT_DHCP 174 if (dhcp_ok) { 175 u_int32_t leasetime; 176 bp->bp_vend[6] = DHCPREQUEST; 177 bp->bp_vend[7] = TAG_REQ_ADDR; 178 bp->bp_vend[8] = 4; 179 bcopy(&rbuf.rbootp.bp_yiaddr, &bp->bp_vend[9], 4); 180 bp->bp_vend[13] = TAG_SERVERID; 181 bp->bp_vend[14] = 4; 182 bcopy(&dhcp_serverip.s_addr, &bp->bp_vend[15], 4); 183 bp->bp_vend[19] = TAG_LEASETIME; 184 bp->bp_vend[20] = 4; 185 leasetime = htonl(300); 186 bcopy(&leasetime, &bp->bp_vend[21], 4); 187 /* 188 * Insert a NetBSD Vendor Class Identifier option. 189 */ 190 sprintf(vci, "NetBSD:%s:libsa", MACHINE); 191 vcilen = strlen(vci); 192 bp->bp_vend[25] = TAG_CLASSID; 193 bp->bp_vend[26] = vcilen; 194 bcopy(vci, &bp->bp_vend[27], vcilen); 195 bp->bp_vend[27 + vcilen] = TAG_END; 196 197 expected_dhcpmsgtype = DHCPACK; 198 199 if (sendrecv(d, 200 bootpsend, bp, sizeof(*bp), 201 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)) 202 == -1) { 203 printf("DHCPREQUEST failed\n"); 204 return; 205 } 206 } 207 #endif 208 209 myip = d->myip = rbuf.rbootp.bp_yiaddr; 210 servip = rbuf.rbootp.bp_siaddr; 211 if (rootip.s_addr == INADDR_ANY) 212 rootip = servip; 213 bcopy(rbuf.rbootp.bp_file, bootfile, sizeof(bootfile)); 214 bootfile[sizeof(bootfile) - 1] = '\0'; 215 216 if (IN_CLASSA(myip.s_addr)) 217 nmask = IN_CLASSA_NET; 218 else if (IN_CLASSB(myip.s_addr)) 219 nmask = IN_CLASSB_NET; 220 else 221 nmask = IN_CLASSC_NET; 222 #ifdef BOOTP_DEBUG 223 if (debug) 224 printf("'native netmask' is %s\n", intoa(nmask)); 225 #endif 226 227 /* Get subnet (or natural net) mask */ 228 netmask = nmask; 229 if (smask) 230 netmask = smask; 231 #ifdef BOOTP_DEBUG 232 if (debug) 233 printf("mask: %s\n", intoa(netmask)); 234 #endif 235 236 /* We need a gateway if root is on a different net */ 237 if (!SAMENET(myip, rootip, netmask)) { 238 #ifdef BOOTP_DEBUG 239 if (debug) 240 printf("need gateway for root ip\n"); 241 #endif 242 } 243 244 /* Toss gateway if on a different net */ 245 if (!SAMENET(myip, gateip, netmask)) { 246 #ifdef BOOTP_DEBUG 247 if (debug) 248 printf("gateway ip (%s) bad\n", inet_ntoa(gateip)); 249 #endif 250 gateip.s_addr = 0; 251 } 252 253 #ifdef BOOTP_DEBUG 254 if (debug) { 255 printf("client addr: %s\n", inet_ntoa(myip)); 256 if (smask) 257 printf("subnet mask: %s\n", intoa(smask)); 258 if (gateip.s_addr != 0) 259 printf("net gateway: %s\n", inet_ntoa(gateip)); 260 printf("server addr: %s\n", inet_ntoa(rootip)); 261 if (rootpath[0] != '\0') 262 printf("server path: %s\n", rootpath); 263 if (bootfile[0] != '\0') 264 printf("file name: %s\n", bootfile); 265 } 266 #endif 267 268 /* Bump xid so next request will be unique. */ 269 ++d->xid; 270 } 271 272 /* Transmit a bootp request */ 273 static ssize_t 274 bootpsend(d, pkt, len) 275 struct iodesc *d; 276 void *pkt; 277 size_t len; 278 { 279 struct bootp *bp; 280 281 #ifdef BOOTP_DEBUG 282 if (debug) 283 printf("bootpsend: d=%lx called.\n", (long)d); 284 #endif 285 286 bp = pkt; 287 bp->bp_secs = htons((u_short)(getsecs() - bot)); 288 289 #ifdef BOOTP_DEBUG 290 if (debug) 291 printf("bootpsend: calling sendudp\n"); 292 #endif 293 294 return (sendudp(d, pkt, len)); 295 } 296 297 static ssize_t 298 bootprecv(d, pkt, len, tleft) 299 struct iodesc *d; 300 void *pkt; 301 size_t len; 302 time_t tleft; 303 { 304 ssize_t n; 305 struct bootp *bp; 306 307 #ifdef BOOTP_DEBUGx 308 if (debug) 309 printf("bootp_recvoffer: called\n"); 310 #endif 311 312 n = readudp(d, pkt, len, tleft); 313 if (n == -1 || (size_t)n < sizeof(struct bootp) - BOOTP_VENDSIZE) 314 goto bad; 315 316 bp = (struct bootp *)pkt; 317 318 #ifdef BOOTP_DEBUG 319 if (debug) 320 printf("bootprecv: checked. bp = 0x%lx, n = %d\n", 321 (long)bp, (int)n); 322 #endif 323 if (bp->bp_xid != htonl(d->xid)) { 324 #ifdef BOOTP_DEBUG 325 if (debug) { 326 printf("bootprecv: expected xid 0x%lx, got 0x%x\n", 327 d->xid, ntohl(bp->bp_xid)); 328 } 329 #endif 330 goto bad; 331 } 332 333 /* protect against bogus addresses sent by DHCP servers */ 334 if (bp->bp_yiaddr.s_addr == INADDR_ANY || 335 bp->bp_yiaddr.s_addr == INADDR_BROADCAST) 336 goto bad; 337 338 #ifdef BOOTP_DEBUG 339 if (debug) 340 printf("bootprecv: got one!\n"); 341 #endif 342 343 /* Suck out vendor info */ 344 if (memcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) { 345 if (vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)) != 0) 346 goto bad; 347 } 348 #ifdef BOOTP_VEND_CMU 349 else if (memcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0) 350 vend_cmu(bp->bp_vend); 351 #endif 352 else 353 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend); 354 355 return (n); 356 bad: 357 errno = 0; 358 return (-1); 359 } 360 361 static int 362 vend_rfc1048(cp, len) 363 u_char *cp; 364 u_int len; 365 { 366 u_char *ep; 367 int size; 368 u_char tag; 369 370 #ifdef BOOTP_DEBUG 371 if (debug) 372 printf("vend_rfc1048 bootp info. len=%d\n", len); 373 #endif 374 ep = cp + len; 375 376 /* Step over magic cookie */ 377 cp += sizeof(int); 378 379 while (cp < ep) { 380 tag = *cp++; 381 size = *cp++; 382 if (tag == TAG_END) 383 break; 384 385 if (tag == TAG_SUBNET_MASK) { 386 bcopy(cp, &smask, sizeof(smask)); 387 } 388 if (tag == TAG_GATEWAY) { 389 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr)); 390 } 391 if (tag == TAG_SWAPSERVER) { 392 /* let it override bp_siaddr */ 393 bcopy(cp, &rootip.s_addr, sizeof(rootip.s_addr)); 394 } 395 if (tag == TAG_ROOTPATH) { 396 strncpy(rootpath, (char *)cp, sizeof(rootpath)); 397 rootpath[size] = '\0'; 398 } 399 if (tag == TAG_HOSTNAME) { 400 strncpy(hostname, (char *)cp, sizeof(hostname)); 401 hostname[size] = '\0'; 402 } 403 #ifdef SUPPORT_DHCP 404 if (tag == TAG_DHCP_MSGTYPE) { 405 if (*cp != expected_dhcpmsgtype) 406 return (-1); 407 dhcp_ok = 1; 408 } 409 if (tag == TAG_SERVERID) { 410 bcopy(cp, &dhcp_serverip.s_addr, 411 sizeof(dhcp_serverip.s_addr)); 412 } 413 #endif 414 #ifdef SUPPORT_LINUX 415 if (tag == TAG_LINUX_CMDLINE) { 416 strncpy(linuxcmdline, (char *)cp, sizeof(linuxcmdline)); 417 linuxcmdline[size] = '\0'; 418 } 419 #endif 420 cp += size; 421 } 422 return (0); 423 } 424 425 #ifdef BOOTP_VEND_CMU 426 static void 427 vend_cmu(cp) 428 u_char *cp; 429 { 430 struct cmu_vend *vp; 431 432 #ifdef BOOTP_DEBUG 433 if (debug) 434 printf("vend_cmu bootp info.\n"); 435 #endif 436 vp = (struct cmu_vend *)cp; 437 438 if (vp->v_smask.s_addr != 0) { 439 smask = vp->v_smask.s_addr; 440 } 441 if (vp->v_dgate.s_addr != 0) { 442 gateip = vp->v_dgate; 443 } 444 } 445 #endif 446
Indexes created Tue Sep 30 06:09:59 GMT 2025