1 /* $OpenBSD: bootp.c,v 1.8 1999/12/18 16:42:19 deraadt Exp $ */ 2 /* $NetBSD: bootp.c,v 1.10 1996/10/13 02:28:59 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: bootp.c,v 1.4 93/09/11 03:13:51 leres Exp (LBL) 41 */ 42 43 #include <sys/types.h> 44 #include <sys/socket.h> 45 #include <netinet/in.h> 46 #include <netinet/in_systm.h> 47 48 #include "stand.h" 49 #include "net.h" 50 #include "netif.h" 51 #include "bootp.h" 52 53 static n_long nmask, smask; 54 55 static time_t bot; 56 57 static char vm_rfc1048[4] = VM_RFC1048; 58 static char vm_cmu[4] = VM_CMU; 59 60 /* Local forwards */ 61 static ssize_t bootpsend __P((struct iodesc *, void *, size_t)); 62 static ssize_t bootprecv __P((struct iodesc *, void *, size_t, time_t)); 63 static void vend_cmu __P((u_char *)); 64 static void vend_rfc1048 __P((u_char *, u_int)); 65 66 /* Fetch required bootp infomation */ 67 void 68 bootp(sock) 69 int sock; 70 { 71 struct iodesc *d; 72 register struct bootp *bp; 73 struct { 74 u_char header[HEADER_SIZE]; 75 struct bootp wbootp; 76 } wbuf; 77 struct { 78 u_char header[HEADER_SIZE]; 79 struct bootp rbootp; 80 } rbuf; 81 82 #ifdef BOOTP_DEBUG 83 if (debug) 84 printf("bootp: socket=%d\n", sock); 85 #endif 86 if (!bot) 87 bot = getsecs(); 88 89 if (!(d = socktodesc(sock))) { 90 printf("bootp: bad socket. %d\n", sock); 91 return; 92 } 93 #ifdef BOOTP_DEBUG 94 if (debug) 95 printf("bootp: d=%x\n", (u_int)d); 96 #endif 97 98 bp = &wbuf.wbootp; 99 bzero(bp, sizeof(*bp)); 100 101 bp->bp_op = BOOTREQUEST; 102 bp->bp_htype = HTYPE_ETHERNET; /* 10Mb Ethernet (48 bits) */ 103 bp->bp_hlen = 6; 104 bp->bp_xid = htonl(d->xid); 105 MACPY(d->myea, bp->bp_chaddr); 106 bzero(bp->bp_file, sizeof(bp->bp_file)); 107 bcopy(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)); 108 109 d->myip = myip; 110 d->myport = htons(IPPORT_BOOTPC); 111 d->destip.s_addr = INADDR_BROADCAST; 112 d->destport = htons(IPPORT_BOOTPS); 113 114 (void)sendrecv(d, 115 bootpsend, bp, sizeof(*bp), 116 bootprecv, &rbuf.rbootp, sizeof(rbuf.rbootp)); 117 118 /* Bump xid so next request will be unique. */ 119 ++d->xid; 120 } 121 122 /* Transmit a bootp request */ 123 static ssize_t 124 bootpsend(d, pkt, len) 125 register struct iodesc *d; 126 register void *pkt; 127 register size_t len; 128 { 129 register struct bootp *bp; 130 131 #ifdef BOOTP_DEBUG 132 if (debug) 133 printf("bootpsend: d=%x called.\n", (u_int)d); 134 #endif 135 136 bp = pkt; 137 bp->bp_secs = htons((u_short)(getsecs() - bot)); 138 139 #ifdef BOOTP_DEBUG 140 if (debug) 141 printf("bootpsend: calling sendudp\n"); 142 #endif 143 144 return (sendudp(d, pkt, len)); 145 } 146 147 /* Returns 0 if this is the packet we're waiting for else -1 (and errno == 0) */ 148 static ssize_t 149 bootprecv(d, pkt, len, tleft) 150 register struct iodesc *d; 151 register void *pkt; 152 register size_t len; 153 time_t tleft; 154 { 155 register ssize_t n; 156 register struct bootp *bp; 157 158 #ifdef BOOTP_DEBUG 159 if (debug) 160 printf("bootprecv: called\n"); 161 #endif 162 163 n = readudp(d, pkt, len, tleft); 164 if (n < 0 || (size_t)n < sizeof(struct bootp)) 165 goto bad; 166 167 bp = (struct bootp *)pkt; 168 169 #ifdef BOOTP_DEBUG 170 if (debug) 171 printf("bootprecv: checked. bp = 0x%x, n = %d\n", 172 (unsigned)bp, n); 173 #endif 174 if (bp->bp_xid != htonl(d->xid)) { 175 #ifdef BOOTP_DEBUG 176 if (debug) { 177 printf("bootprecv: expected xid 0x%lx, got 0x%lx\n", 178 d->xid, ntohl(bp->bp_xid)); 179 } 180 #endif 181 goto bad; 182 } 183 184 #ifdef BOOTP_DEBUG 185 if (debug) 186 printf("bootprecv: got one!\n"); 187 #endif 188 189 /* Pick up our ip address (and natural netmask) */ 190 myip = d->myip = bp->bp_yiaddr; 191 #ifdef BOOTP_DEBUG 192 if (debug) 193 printf("our ip address is %s\n", inet_ntoa(d->myip)); 194 #endif 195 if (IN_CLASSA(d->myip.s_addr)) 196 nmask = IN_CLASSA_NET; 197 else if (IN_CLASSB(d->myip.s_addr)) 198 nmask = IN_CLASSB_NET; 199 else 200 nmask = IN_CLASSC_NET; 201 #ifdef BOOTP_DEBUG 202 if (debug) 203 printf("'native netmask' is %s\n", intoa(nmask)); 204 #endif 205 206 /* Pick up root or swap server address and file spec. */ 207 if (bp->bp_siaddr.s_addr != 0) 208 rootip = bp->bp_siaddr; 209 if (bp->bp_file[0] != '\0') { 210 strncpy(bootfile, (char *)bp->bp_file, sizeof(bootfile)); 211 bootfile[sizeof(bootfile) - 1] = '\0'; 212 } 213 214 /* Suck out vendor info */ 215 if (bcmp(vm_cmu, bp->bp_vend, sizeof(vm_cmu)) == 0) 216 vend_cmu(bp->bp_vend); 217 else if (bcmp(vm_rfc1048, bp->bp_vend, sizeof(vm_rfc1048)) == 0) 218 vend_rfc1048(bp->bp_vend, sizeof(bp->bp_vend)); 219 else 220 printf("bootprecv: unknown vendor 0x%lx\n", (long)bp->bp_vend); 221 222 /* Check subnet mask against net mask; toss if bogus */ 223 if ((nmask & smask) != nmask) { 224 #ifdef BOOTP_DEBUG 225 if (debug) 226 printf("subnet mask (%s) bad\n", intoa(smask)); 227 #endif 228 smask = 0; 229 } 230 231 /* Get subnet (or natural net) mask */ 232 netmask = nmask; 233 if (smask) 234 netmask = smask; 235 #ifdef BOOTP_DEBUG 236 if (debug) 237 printf("mask: %s\n", intoa(netmask)); 238 #endif 239 240 /* We need a gateway if root or swap is on a different net */ 241 if (!SAMENET(d->myip, rootip, netmask)) { 242 #ifdef BOOTP_DEBUG 243 if (debug) 244 printf("need gateway for root ip\n"); 245 #endif 246 } 247 248 if (!SAMENET(d->myip, swapip, netmask)) { 249 #ifdef BOOTP_DEBUG 250 if (debug) 251 printf("need gateway for swap ip\n"); 252 #endif 253 } 254 255 /* Toss gateway if on a different net */ 256 if (!SAMENET(d->myip, gateip, netmask)) { 257 #ifdef BOOTP_DEBUG 258 if (debug) 259 printf("gateway ip (%s) bad\n", inet_ntoa(gateip)); 260 #endif 261 gateip.s_addr = 0; 262 } 263 264 return (n); 265 266 bad: 267 errno = 0; 268 return (-1); 269 } 270 271 static void 272 vend_cmu(cp) 273 u_char *cp; 274 { 275 register struct cmu_vend *vp; 276 277 #ifdef BOOTP_DEBUG 278 if (debug) 279 printf("vend_cmu bootp info.\n"); 280 #endif 281 vp = (struct cmu_vend *)cp; 282 283 if (vp->v_smask.s_addr != 0) { 284 smask = vp->v_smask.s_addr; 285 } 286 if (vp->v_dgate.s_addr != 0) { 287 gateip = vp->v_dgate; 288 } 289 } 290 291 static void 292 vend_rfc1048(cp, len) 293 register u_char *cp; 294 u_int len; 295 { 296 register u_char *ep; 297 register int size; 298 register u_char tag; 299 300 #ifdef BOOTP_DEBUG 301 if (debug) 302 printf("vend_rfc1048 bootp info. len=%d\n", len); 303 #endif 304 ep = cp + len; 305 306 /* Step over magic cookie */ 307 cp += sizeof(int); 308 309 while (cp < ep) { 310 tag = *cp++; 311 size = *cp++; 312 if (tag == TAG_END) 313 break; 314 315 if (tag == TAG_SUBNET_MASK) { 316 bcopy(cp, &smask, sizeof(smask)); 317 } 318 if (tag == TAG_GATEWAY) { 319 bcopy(cp, &gateip.s_addr, sizeof(gateip.s_addr)); 320 } 321 if (tag == TAG_SWAPSERVER) { 322 bcopy(cp, &swapip.s_addr, sizeof(swapip.s_addr)); 323 } 324 if (tag == TAG_DOMAIN_SERVER) { 325 bcopy(cp, &nameip.s_addr, sizeof(nameip.s_addr)); 326 } 327 if (tag == TAG_ROOTPATH) { 328 strncpy(rootpath, (char *)cp, sizeof(rootpath)); 329 rootpath[size] = '\0'; 330 } 331 if (tag == TAG_HOSTNAME) { 332 strncpy(hostname, (char *)cp, sizeof(hostname)); 333 hostname[size] = '\0'; 334 } 335 if (tag == TAG_DOMAINNAME) { 336 strncpy(domainname, (char *)cp, sizeof(domainname)); 337 domainname[size] = '\0'; 338 } 339 cp += size; 340 } 341 } 342