1 /* $NetBSD: bootp.c,v 1.4 1995/02/21 10:14:53 mycroft 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 #include <string.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 size_t bootpsend __P((struct iodesc *, void *, size_t)); 62 static size_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 = 1; /* 10Mb Ethernet (48 bits) */ 103 bp->bp_hlen = 6; 104 bp->bp_xid = 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 = IPPORT_BOOTPC; 111 d->destip = INADDR_BROADCAST; 112 d->destport = 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 size_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 = (u_long)(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 size_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 struct bootp *bp; 156 157 #ifdef BOOTP_DEBUG 158 if (debug) 159 printf("bootprecv: called\n"); 160 #endif 161 162 len = readudp(d, pkt, len, tleft); 163 if (len == -1 || len < sizeof(struct bootp)) 164 goto bad; 165 166 bp = (struct bootp *)pkt; 167 NTOHL(bp->bp_xid); 168 169 #ifdef BOOTP_DEBUG 170 if (debug) 171 printf("bootprecv: checked. bp = 0x%x, len = %d\n", 172 (unsigned)bp, len); 173 #endif 174 if (bp->bp_xid != d->xid) { 175 #ifdef BOOTP_DEBUG 176 if (debug) { 177 printf("bootprecv: expected xid 0x%x, got 0x%x\n", 178 d->xid, 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 = ntohl(bp->bp_yiaddr.s_addr); 191 #ifdef BOOTP_DEBUG 192 if (debug) 193 printf("our ip address is %s\n", intoa(d->myip)); 194 #endif 195 if (IN_CLASSA(d->myip)) 196 nmask = IN_CLASSA_NET; 197 else if (IN_CLASSB(d->myip)) 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 = ntohl(bp->bp_siaddr.s_addr); 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%x\n", (int)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 mask = nmask; 233 if (smask) 234 mask = smask; 235 #ifdef BOOTP_DEBUG 236 if (debug) 237 printf("mask: %s\n", intoa(mask)); 238 #endif 239 240 /* We need a gateway if root or swap is on a different net */ 241 if (!SAMENET(d->myip, rootip, mask)) { 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, mask)) { 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, mask)) { 257 #ifdef BOOTP_DEBUG 258 if (debug) 259 printf("gateway ip (%s) bad\n", intoa(gateip)); 260 #endif 261 gateip = 0; 262 } 263 264 return (0); 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 = ntohl(vp->v_smask.s_addr); 285 } 286 if (vp->v_dgate.s_addr != 0) { 287 gateip = ntohl(vp->v_dgate.s_addr); 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(long); 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 smask = ntohl(smask); 318 } 319 if (tag == TAG_GATEWAY) { 320 bcopy(cp, &gateip, sizeof(gateip)); 321 gateip = ntohl(gateip); 322 } 323 if (tag == TAG_SWAPSERVER) { 324 bcopy(cp, &swapip, sizeof(swapip)); 325 swapip = ntohl(swapip); 326 } 327 if (tag == TAG_DOMAIN_SERVER) { 328 bcopy(cp, &nameip, sizeof(nameip)); 329 nameip = ntohl(nameip); 330 } 331 if (tag == TAG_ROOTPATH) { 332 strncpy(rootpath, cp, sizeof(rootpath)); 333 rootpath[size] = '\0'; 334 } 335 if (tag == TAG_HOSTNAME) { 336 strncpy(hostname, cp, sizeof(hostname)); 337 hostname[size] = '\0'; 338 } 339 if (tag == TAG_DOMAINNAME) { 340 strncpy(domainname, cp, sizeof(domainname)); 341 domainname[size] = '\0'; 342 } 343 cp += size; 344 } 345 } 346