1 /* $NetBSD: nfs_bootdhcp.c,v 1.18 2001/11/10 10:59:09 lukem Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 1997 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Adam Glass and Gordon W. Ross. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * Support for NFS diskless booting with BOOTP (RFC951, RFC1048) 41 * 42 * History: 43 * 44 * Tor Egge developed the initial version of this code based on 45 * the Sun RPC/bootparam sources nfs_boot.c and krpc_subr.c and 46 * submitted that work to NetBSD as bugreport "kern/2351" on 47 * 29 Apr 1996. 48 * 49 * Gordon Ross reorganized Tor's version into this form and 50 * integrated it into the NetBSD sources during Aug 1997. 51 */ 52 53 #include <sys/cdefs.h> 54 __KERNEL_RCSID(0, "$NetBSD: nfs_bootdhcp.c,v 1.18 2001/11/10 10:59:09 lukem Exp $"); 55 56 #include "opt_nfs_boot.h" 57 58 #include <sys/param.h> 59 #include <sys/systm.h> 60 #include <sys/kernel.h> 61 #include <sys/device.h> 62 #include <sys/ioctl.h> 63 #include <sys/proc.h> 64 #include <sys/mount.h> 65 #include <sys/mbuf.h> 66 #include <sys/reboot.h> 67 #include <sys/socket.h> 68 #include <sys/socketvar.h> 69 70 #include <net/if.h> 71 #include <net/if_types.h> 72 #include <net/if_arp.h> /* ARPHRD_ETHER, etc. */ 73 #include <net/if_dl.h> 74 #include <net/if_ether.h> 75 #include <net/route.h> 76 77 #include <netinet/in.h> 78 #include <netinet/if_inarp.h> 79 80 #include <nfs/rpcv2.h> 81 82 #include <nfs/nfsproto.h> 83 #include <nfs/nfs.h> 84 #include <nfs/nfsmount.h> 85 #include <nfs/nfsdiskless.h> 86 87 /* 88 * There are two implementations of NFS diskless boot. 89 * This implementation uses BOOTP (RFC951, RFC1048), and 90 * the other uses Sun RPC/bootparams (nfs_bootparam.c). 91 * 92 * This method gets everything it needs with one BOOTP 93 * request and reply. Note that this actually uses only 94 * the old BOOTP functionality subset of DHCP. It is not 95 * clear that DHCP provides any advantage over BOOTP for 96 * diskless boot. DHCP allows the server to assign an IP 97 * address without any a-priori knowledge of the client, 98 * but we require that the server has a-priori knowledge 99 * of the client so it can export our (unique) NFS root. 100 * Given that the server needs a-priori knowledge about 101 * the client anyway, it might as well assign a fixed IP 102 * address for the client and support BOOTP. 103 * 104 * On the other hand, disk-FULL clients may use DHCP, but 105 * in that case the DHCP client should be user-mode code, 106 * and has no bearing on the code below. -gwr 107 */ 108 109 /* Begin stuff from bootp.h */ 110 /* Definitions from RFC951 */ 111 #define BP_CHADDR_LEN 16 112 #define BP_SNAME_LEN 64 113 #define BP_FILE_LEN 128 114 #define BP_VEND_LEN 64 115 struct bootp { 116 u_int8_t bp_op; /* packet opcode type */ 117 u_int8_t bp_htype; /* hardware addr type */ 118 u_int8_t bp_hlen; /* hardware addr length */ 119 u_int8_t bp_hops; /* gateway hops */ 120 u_int32_t bp_xid; /* transaction ID */ 121 u_int16_t bp_secs; /* seconds since boot began */ 122 u_int16_t bp_flags; /* RFC1532 broadcast, etc. */ 123 struct in_addr bp_ciaddr; /* client IP address */ 124 struct in_addr bp_yiaddr; /* 'your' IP address */ 125 struct in_addr bp_siaddr; /* server IP address */ 126 struct in_addr bp_giaddr; /* gateway IP address */ 127 u_int8_t bp_chaddr[BP_CHADDR_LEN]; /* client hardware address */ 128 char bp_sname[BP_SNAME_LEN]; /* server host name */ 129 char bp_file[BP_FILE_LEN]; /* boot file name */ 130 u_int8_t bp_vend[BP_VEND_LEN]; /* RFC1048 options */ 131 /* 132 * Note that BOOTP packets are allowed to be longer 133 * (see RFC 1532 sect. 2.1) and common practice is to 134 * allow the option data in bp_vend to extend into the 135 * additional space provided in longer packets. 136 */ 137 }; 138 139 #define IPPORT_BOOTPS 67 140 #define IPPORT_BOOTPC 68 141 142 #define BOOTREQUEST 1 143 #define BOOTREPLY 2 144 145 /* 146 * Is this available from the sockaddr_dl somehow? 147 * Perhaps (struct arphdr)->ar_hrd = ARPHRD_ETHER? 148 * The interface has ->if_type but not the ARP fmt. 149 */ 150 #define HTYPE_ETHERNET 1 151 #define HTYPE_IEEE802 6 152 153 /* 154 * Vendor magic cookie (v_magic) for RFC1048 155 */ 156 static const u_int8_t vm_rfc1048[4] = { 99, 130, 83, 99 }; 157 158 /* 159 * Tag values used to specify what information is being supplied in 160 * the vendor (options) data area of the packet. 161 */ 162 /* RFC 1048 */ 163 #define TAG_END ((unsigned char) 255) 164 #define TAG_PAD ((unsigned char) 0) 165 #define TAG_SUBNET_MASK ((unsigned char) 1) 166 #define TAG_TIME_OFFSET ((unsigned char) 2) 167 #define TAG_GATEWAY ((unsigned char) 3) 168 #define TAG_TIME_SERVER ((unsigned char) 4) 169 #define TAG_NAME_SERVER ((unsigned char) 5) 170 #define TAG_DOMAIN_SERVER ((unsigned char) 6) 171 #define TAG_LOG_SERVER ((unsigned char) 7) 172 #define TAG_COOKIE_SERVER ((unsigned char) 8) 173 #define TAG_LPR_SERVER ((unsigned char) 9) 174 #define TAG_IMPRESS_SERVER ((unsigned char) 10) 175 #define TAG_RLP_SERVER ((unsigned char) 11) 176 #define TAG_HOST_NAME ((unsigned char) 12) 177 #define TAG_BOOT_SIZE ((unsigned char) 13) 178 /* RFC 1395 */ 179 #define TAG_DUMP_FILE ((unsigned char) 14) 180 #define TAG_DOMAIN_NAME ((unsigned char) 15) 181 #define TAG_SWAP_SERVER ((unsigned char) 16) 182 #define TAG_ROOT_PATH ((unsigned char) 17) 183 /* End of stuff from bootp.h */ 184 185 #ifdef NFS_BOOT_DHCP 186 #define TAG_REQ_ADDR ((unsigned char) 50) 187 #define TAG_LEASETIME ((unsigned char) 51) 188 #define TAG_OVERLOAD ((unsigned char) 52) 189 #define TAG_DHCP_MSGTYPE ((unsigned char) 53) 190 #define TAG_SERVERID ((unsigned char) 54) 191 #define TAG_PARAM_REQ ((unsigned char) 55) 192 #define TAG_MSG ((unsigned char) 56) 193 #define TAG_MAXSIZE ((unsigned char) 57) 194 #define TAG_T1 ((unsigned char) 58) 195 #define TAG_T2 ((unsigned char) 59) 196 #define TAG_CLASSID ((unsigned char) 60) 197 #define TAG_CLIENTID ((unsigned char) 61) 198 #endif 199 200 #ifdef NFS_BOOT_DHCP 201 #define DHCPDISCOVER 1 202 #define DHCPOFFER 2 203 #define DHCPREQUEST 3 204 #define DHCPDECLINE 4 205 #define DHCPACK 5 206 #define DHCPNAK 6 207 #define DHCPRELEASE 7 208 #endif 209 210 #ifdef NFS_BOOT_DHCP 211 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+312-64) 212 #else 213 /* 214 * The "extended" size is somewhat arbitrary, but is 215 * constrained by the maximum message size specified 216 * by RFC1533 (567 total). This value increases the 217 * space for options from 64 bytes to 256 bytes. 218 */ 219 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+256-64) 220 #endif 221 #define BOOTP_SIZE_MIN (sizeof(struct bootp)) 222 223 /* Convenience macro */ 224 #define INTOHL(ina) ((u_int32_t)ntohl((ina).s_addr)) 225 226 static int bootpc_call __P((struct nfs_diskless *, struct proc *)); 227 static void bootp_extract __P((struct bootp *, int, struct nfs_diskless *)); 228 229 /* #define DEBUG XXX */ 230 231 #ifdef DEBUG 232 #define DPRINT(s) printf("nfs_boot: %s\n", s) 233 #else 234 #define DPRINT(s) (void)0 235 #endif 236 237 238 /* 239 * Get our boot parameters using BOOTP. 240 */ 241 int 242 nfs_bootdhcp(nd, procp) 243 struct nfs_diskless *nd; 244 struct proc *procp; 245 { 246 struct ifnet *ifp = nd->nd_ifp; 247 int error; 248 249 /* 250 * Do enough of ifconfig(8) so that the chosen interface 251 * can talk to the servers. Use address zero for now. 252 */ 253 error = nfs_boot_setaddress(ifp, procp, INADDR_ANY, INADDR_ANY, 254 INADDR_BROADCAST); 255 if (error) { 256 printf("nfs_boot: set ifaddr zero, error=%d\n", error); 257 return (error); 258 } 259 260 /* This function call does the real send/recv work. */ 261 error = bootpc_call(nd, procp); 262 263 /* Get rid of the temporary (zero) IP address. */ 264 (void) nfs_boot_deladdress(ifp, procp, INADDR_ANY); 265 266 /* NOW we can test the error from bootpc_call. */ 267 if (error) 268 goto out; 269 270 /* 271 * Do ifconfig with our real IP address and mask. 272 */ 273 error = nfs_boot_setaddress(ifp, procp, nd->nd_myip.s_addr, 274 nd->nd_mask.s_addr, INADDR_ANY); 275 if (error) { 276 printf("nfs_boot: set ifaddr real, error=%d\n", error); 277 goto out; 278 } 279 280 out: 281 if (error) { 282 (void) nfs_boot_ifupdown(ifp, procp, 0); 283 nfs_boot_flushrt(ifp); 284 } 285 return (error); 286 } 287 288 struct bootpcontext { 289 int xid; 290 u_char *haddr; 291 u_char halen; 292 struct bootp *replybuf; 293 int replylen; 294 #ifdef NFS_BOOT_DHCP 295 char expected_dhcpmsgtype, dhcp_ok; 296 struct in_addr dhcp_serverip; 297 #endif 298 }; 299 300 static int bootpset __P((struct mbuf*, void*, int)); 301 static int bootpcheck __P((struct mbuf*, void*)); 302 303 static int 304 bootpset(m, context, waited) 305 struct mbuf *m; 306 void *context; 307 int waited; 308 { 309 struct bootp *bootp; 310 311 /* we know it's contigous (in 1 mbuf cluster) */ 312 bootp = mtod(m, struct bootp*); 313 314 bootp->bp_secs = htons(waited); 315 316 return (0); 317 } 318 319 static int 320 bootpcheck(m, context) 321 struct mbuf *m; 322 void *context; 323 { 324 struct bootp *bootp; 325 struct bootpcontext *bpc = context; 326 u_int tag, len; 327 u_char *p, *limit; 328 329 /* 330 * Is this a valid reply? 331 */ 332 if (m->m_pkthdr.len < BOOTP_SIZE_MIN) { 333 DPRINT("short packet"); 334 return (-1); 335 } 336 if (m->m_pkthdr.len > BOOTP_SIZE_MAX) { 337 DPRINT("long packet"); 338 return (-1); 339 } 340 341 /* 342 * don't make first checks more expensive than necessary 343 */ 344 #define ofs(what, elem) ((int)&(((what *)0)->elem)) 345 if (m->m_len < ofs(struct bootp, bp_secs)) { 346 m = m_pullup(m, ofs(struct bootp, bp_secs)); 347 if (m == NULL) 348 return (-1); 349 } 350 #undef ofs 351 bootp = mtod(m, struct bootp*); 352 353 if (bootp->bp_op != BOOTREPLY) { 354 DPRINT("not reply"); 355 return (-1); 356 } 357 if (bootp->bp_hlen != bpc->halen) { 358 DPRINT("bad hwa_len"); 359 return (-1); 360 } 361 if (memcmp(bootp->bp_chaddr, bpc->haddr, bpc->halen)) { 362 DPRINT("wrong hwaddr"); 363 return (-1); 364 } 365 if (bootp->bp_xid != bpc->xid) { 366 DPRINT("wrong xid"); 367 return (-1); 368 } 369 370 /* 371 * OK, it's worth to look deeper. 372 * We copy the mbuf into a flat buffer here because 373 * m_pullup() is a bit limited for this purpose 374 * (doesn't allocate a cluster if necessary). 375 */ 376 bpc->replylen = m->m_pkthdr.len; 377 m_copydata(m, 0, bpc->replylen, (caddr_t)bpc->replybuf); 378 bootp = bpc->replybuf; 379 380 /* 381 * Check if the IP address we get looks correct. 382 * (DHCP servers can send junk to unknown clients.) 383 * XXX more checks might be needed 384 */ 385 if (bootp->bp_yiaddr.s_addr == INADDR_ANY || 386 bootp->bp_yiaddr.s_addr == INADDR_BROADCAST) { 387 printf("nfs_boot: wrong IP addr %s", 388 inet_ntoa(bootp->bp_yiaddr)); 389 goto warn; 390 } 391 392 /* 393 * Check the vendor data. 394 */ 395 if (memcmp(bootp->bp_vend, vm_rfc1048, 4)) { 396 printf("nfs_boot: reply missing options"); 397 goto warn; 398 } 399 p = &bootp->bp_vend[4]; 400 limit = ((char*)bootp) + bpc->replylen; 401 while (p < limit) { 402 tag = *p++; 403 if (tag == TAG_END) 404 break; 405 if (tag == TAG_PAD) 406 continue; 407 len = *p++; 408 if ((p + len) > limit) { 409 printf("nfs_boot: option %d too long", tag); 410 goto warn; 411 } 412 switch (tag) { 413 #ifdef NFS_BOOT_DHCP 414 case TAG_DHCP_MSGTYPE: 415 if (*p != bpc->expected_dhcpmsgtype) 416 return (-1); 417 bpc->dhcp_ok = 1; 418 break; 419 case TAG_SERVERID: 420 memcpy(&bpc->dhcp_serverip.s_addr, p, 421 sizeof(bpc->dhcp_serverip.s_addr)); 422 break; 423 #endif 424 default: 425 break; 426 } 427 p += len; 428 } 429 return (0); 430 431 warn: 432 printf(" (bad reply from %s)\n", inet_ntoa(bootp->bp_siaddr)); 433 return (-1); 434 } 435 436 static int 437 bootpc_call(nd, procp) 438 struct nfs_diskless *nd; 439 struct proc *procp; 440 { 441 struct socket *so; 442 struct ifnet *ifp = nd->nd_ifp; 443 static u_int32_t xid = ~0xFF; 444 struct bootp *bootp; /* request */ 445 struct mbuf *m, *nam; 446 struct sockaddr_in *sin; 447 int error; 448 u_char *haddr; 449 u_char hafmt, halen; 450 struct bootpcontext bpc; 451 452 error = socreate(AF_INET, &so, SOCK_DGRAM, 0); 453 if (error) { 454 printf("bootp: socreate, error=%d\n", error); 455 return (error); 456 } 457 458 /* 459 * Initialize to NULL anything that will hold an allocation, 460 * and free each at the end if not null. 461 */ 462 bpc.replybuf = NULL; 463 m = nam = NULL; 464 465 /* Record our H/W (Ethernet) address. */ 466 { struct sockaddr_dl *sdl = ifp->if_sadl; 467 switch (sdl->sdl_type) { 468 case IFT_ISO88025: 469 hafmt = HTYPE_IEEE802; 470 break; 471 case IFT_ETHER: 472 case IFT_FDDI: 473 hafmt = HTYPE_ETHERNET; 474 break; 475 default: 476 printf("bootp: unsupported interface type %d\n", 477 sdl->sdl_type); 478 error = EINVAL; 479 goto out; 480 } 481 halen = sdl->sdl_alen; 482 haddr = (unsigned char *)LLADDR(sdl); 483 } 484 485 /* 486 * Skip the route table when sending on this socket. 487 * If this is not done, ip_output finds the loopback 488 * interface (why?) and then fails because broadcast 489 * is not supported on that interface... 490 */ 491 { int32_t *opt; 492 m = m_get(M_WAIT, MT_SOOPTS); 493 opt = mtod(m, int32_t *); 494 m->m_len = sizeof(*opt); 495 *opt = 1; 496 error = sosetopt(so, SOL_SOCKET, SO_DONTROUTE, m); 497 m = NULL; /* was consumed */ 498 } 499 if (error) { 500 DPRINT("SO_DONTROUTE"); 501 goto out; 502 } 503 504 /* Enable broadcast. */ 505 if ((error = nfs_boot_enbroadcast(so))) { 506 DPRINT("SO_BROADCAST"); 507 goto out; 508 } 509 510 /* Set the receive timeout for the socket. */ 511 if ((error = nfs_boot_setrecvtimo(so))) { 512 DPRINT("SO_RCVTIMEO"); 513 goto out; 514 } 515 516 /* 517 * Bind the local endpoint to a bootp client port. 518 */ 519 if ((error = nfs_boot_sobind_ipport(so, IPPORT_BOOTPC))) { 520 DPRINT("bind failed\n"); 521 goto out; 522 } 523 524 /* 525 * Setup socket address for the server. 526 */ 527 nam = m_get(M_WAIT, MT_SONAME); 528 sin = mtod(nam, struct sockaddr_in *); 529 sin->sin_len = nam->m_len = sizeof(*sin); 530 sin->sin_family = AF_INET; 531 sin->sin_addr.s_addr = INADDR_BROADCAST; 532 sin->sin_port = htons(IPPORT_BOOTPS); 533 534 /* 535 * Allocate buffer used for request 536 */ 537 m = m_gethdr(M_WAIT, MT_DATA); 538 MCLGET(m, M_WAIT); 539 bootp = mtod(m, struct bootp*); 540 m->m_pkthdr.len = m->m_len = BOOTP_SIZE_MAX; 541 m->m_pkthdr.rcvif = NULL; 542 543 /* 544 * Build the BOOTP reqest message. 545 * Note: xid is host order! (opaque to server) 546 */ 547 memset((caddr_t)bootp, 0, BOOTP_SIZE_MAX); 548 bootp->bp_op = BOOTREQUEST; 549 bootp->bp_htype = hafmt; 550 bootp->bp_hlen = halen; /* Hardware address length */ 551 bootp->bp_xid = ++xid; 552 memcpy(bootp->bp_chaddr, haddr, halen); 553 #ifdef NFS_BOOT_BOOTP_REQFILE 554 strncpy(bootp->bp_file, NFS_BOOT_BOOTP_REQFILE, sizeof(bootp->bp_file)); 555 #endif 556 /* Fill-in the vendor data. */ 557 memcpy(bootp->bp_vend, vm_rfc1048, 4); 558 #ifdef NFS_BOOT_DHCP 559 bootp->bp_vend[4] = TAG_DHCP_MSGTYPE; 560 bootp->bp_vend[5] = 1; 561 bootp->bp_vend[6] = DHCPDISCOVER; 562 bootp->bp_vend[7] = TAG_END; 563 #else 564 bootp->bp_vend[4] = TAG_END; 565 #endif 566 567 bpc.xid = xid; 568 bpc.haddr = haddr; 569 bpc.halen = halen; 570 bpc.replybuf = malloc(BOOTP_SIZE_MAX, M_DEVBUF, M_WAITOK); 571 if (bpc.replybuf == NULL) 572 panic("nfs_boot: malloc reply buf"); 573 #ifdef NFS_BOOT_DHCP 574 bpc.expected_dhcpmsgtype = DHCPOFFER; 575 bpc.dhcp_ok = 0; 576 #endif 577 578 error = nfs_boot_sendrecv(so, nam, bootpset, m, 579 bootpcheck, 0, 0, &bpc); 580 if (error) 581 goto out; 582 583 #ifdef NFS_BOOT_DHCP 584 if (bpc.dhcp_ok) { 585 u_int32_t leasetime; 586 bootp->bp_vend[6] = DHCPREQUEST; 587 bootp->bp_vend[7] = TAG_REQ_ADDR; 588 bootp->bp_vend[8] = 4; 589 memcpy(&bootp->bp_vend[9], &bpc.replybuf->bp_yiaddr, 4); 590 bootp->bp_vend[13] = TAG_SERVERID; 591 bootp->bp_vend[14] = 4; 592 memcpy(&bootp->bp_vend[15], &bpc.dhcp_serverip.s_addr, 4); 593 bootp->bp_vend[19] = TAG_LEASETIME; 594 bootp->bp_vend[20] = 4; 595 leasetime = htonl(300); 596 memcpy(&bootp->bp_vend[21], &leasetime, 4); 597 bootp->bp_vend[25] = TAG_END; 598 599 bpc.expected_dhcpmsgtype = DHCPACK; 600 601 error = nfs_boot_sendrecv(so, nam, bootpset, m, 602 bootpcheck, 0, 0, &bpc); 603 if (error) 604 goto out; 605 } 606 #endif 607 608 /* 609 * bootpcheck() has copied the receive mbuf into 610 * the buffer at bpc.replybuf. 611 */ 612 #ifdef NFS_BOOT_DHCP 613 printf("nfs_boot: %s next-server: %s\n", 614 (bpc.dhcp_ok ? "DHCP" : "BOOTP"), 615 #else 616 printf("nfs_boot: BOOTP next-server: %s\n", 617 #endif 618 inet_ntoa(bpc.replybuf->bp_siaddr)); 619 620 bootp_extract(bpc.replybuf, bpc.replylen, nd); 621 622 out: 623 if (bpc.replybuf) 624 free(bpc.replybuf, M_DEVBUF); 625 if (m) 626 m_freem(m); 627 if (nam) 628 m_freem(nam); 629 soclose(so); 630 return (error); 631 } 632 633 static void 634 bootp_extract(bootp, replylen, nd) 635 struct bootp *bootp; 636 int replylen; 637 struct nfs_diskless *nd; 638 { 639 struct sockaddr_in *sin; 640 struct in_addr netmask; 641 struct in_addr gateway; 642 struct in_addr rootserver; 643 char *myname; /* my hostname */ 644 char *mydomain; /* my domainname */ 645 char *rootpath; 646 int mynamelen; 647 int mydomainlen; 648 int rootpathlen; 649 int overloaded; 650 u_int tag, len; 651 u_char *p, *limit; 652 653 /* Default these to "unspecified". */ 654 netmask.s_addr = 0; 655 gateway.s_addr = 0; 656 mydomain = myname = rootpath = NULL; 657 mydomainlen = mynamelen = rootpathlen = 0; 658 /* default root server to bootp next-server */ 659 rootserver = bootp->bp_siaddr; 660 /* assume that server name field is not overloaded by default */ 661 overloaded = 0; 662 663 p = &bootp->bp_vend[4]; 664 limit = ((char*)bootp) + replylen; 665 while (p < limit) { 666 tag = *p++; 667 if (tag == TAG_END) 668 break; 669 if (tag == TAG_PAD) 670 continue; 671 len = *p++; 672 #if 0 /* already done in bootpcheck() */ 673 if ((p + len) > limit) { 674 printf("nfs_boot: option %d too long\n", tag); 675 break; 676 } 677 #endif 678 switch (tag) { 679 case TAG_SUBNET_MASK: 680 memcpy(&netmask, p, 4); 681 break; 682 case TAG_GATEWAY: 683 /* Routers */ 684 memcpy(&gateway, p, 4); 685 break; 686 case TAG_HOST_NAME: 687 if (len >= sizeof(hostname)) { 688 printf("nfs_boot: host name >= %lu bytes", 689 (u_long)sizeof(hostname)); 690 break; 691 } 692 myname = p; 693 mynamelen = len; 694 break; 695 case TAG_DOMAIN_NAME: 696 if (len >= sizeof(domainname)) { 697 printf("nfs_boot: domain name >= %lu bytes", 698 (u_long)sizeof(domainname)); 699 break; 700 } 701 mydomain = p; 702 mydomainlen = len; 703 break; 704 case TAG_ROOT_PATH: 705 /* Leave some room for the server name. */ 706 if (len >= (MNAMELEN-10)) { 707 printf("nfs_boot: rootpath >=%d bytes", 708 (MNAMELEN-10)); 709 break; 710 } 711 rootpath = p; 712 rootpathlen = len; 713 break; 714 case TAG_SWAP_SERVER: 715 /* override NFS server address */ 716 memcpy(&rootserver, p, 4); 717 break; 718 #ifdef NFS_BOOT_DHCP 719 case TAG_OVERLOAD: 720 if (len > 0 && ((*p & 0x02) != 0)) 721 /* 722 * The server name field in the dhcp packet 723 * is overloaded and we can't find server 724 * name there. 725 */ 726 overloaded = 1; 727 break; 728 #endif 729 default: 730 break; 731 } 732 p += len; 733 } 734 735 /* 736 * Store and print network config info. 737 */ 738 if (myname) { 739 myname[mynamelen] = '\0'; 740 strncpy(hostname, myname, sizeof(hostname)); 741 hostnamelen = mynamelen; 742 printf("nfs_boot: my_name=%s\n", hostname); 743 } 744 if (mydomain) { 745 mydomain[mydomainlen] = '\0'; 746 strncpy(domainname, mydomain, sizeof(domainname)); 747 domainnamelen = mydomainlen; 748 printf("nfs_boot: my_domain=%s\n", domainname); 749 } 750 nd->nd_myip = bootp->bp_yiaddr; 751 if (nd->nd_myip.s_addr) 752 printf("nfs_boot: my_addr=%s\n", inet_ntoa(nd->nd_myip)); 753 nd->nd_mask = netmask; 754 if (nd->nd_mask.s_addr) 755 printf("nfs_boot: my_mask=%s\n", inet_ntoa(nd->nd_mask)); 756 nd->nd_gwip = gateway; 757 if (nd->nd_gwip.s_addr) 758 printf("nfs_boot: gateway=%s\n", inet_ntoa(nd->nd_gwip)); 759 760 /* 761 * Store the information about our NFS root mount. 762 * The caller will print it, so be silent here. 763 */ 764 { 765 struct nfs_dlmount *ndm = &nd->nd_root; 766 767 /* Server IP address. */ 768 sin = (struct sockaddr_in *) &ndm->ndm_saddr; 769 memset((caddr_t)sin, 0, sizeof(*sin)); 770 sin->sin_len = sizeof(*sin); 771 sin->sin_family = AF_INET; 772 sin->sin_addr = rootserver; 773 /* Server name. */ 774 if (!overloaded && bootp->bp_sname[0] != 0 && 775 !memcmp(&rootserver, &bootp->bp_siaddr, 776 sizeof(struct in_addr))) { 777 /* standard root server, we have the name */ 778 strncpy(ndm->ndm_host, bootp->bp_sname, BP_SNAME_LEN-1); 779 } else { 780 /* Show the server IP address numerically. */ 781 strncpy(ndm->ndm_host, inet_ntoa(rootserver), 782 BP_SNAME_LEN-1); 783 } 784 len = strlen(ndm->ndm_host); 785 if (rootpath && 786 len + 1 + rootpathlen + 1 <= sizeof(ndm->ndm_host)) { 787 ndm->ndm_host[len++] = ':'; 788 strncpy(ndm->ndm_host + len, 789 rootpath, rootpathlen); 790 ndm->ndm_host[len + rootpathlen] = '\0'; 791 } /* else: upper layer will handle error */ 792 } 793 } 794