1 /* $NetBSD: nfs_bootdhcp.c,v 1.30 2006/03/16 15:55:20 christos 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 1.30 2006/03/16 15:55:20 christos 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 lwp *)); 227 static void bootp_extract __P((struct bootp *, int, struct nfs_diskless *)); 228 229 #ifdef DEBUG_NFS_BOOT_DHCP 230 #define DPRINTF(s) printf s 231 #else 232 #define DPRINTF(s) 233 #endif 234 235 236 /* 237 * Get our boot parameters using BOOTP. 238 */ 239 int 240 nfs_bootdhcp(nd, lwp) 241 struct nfs_diskless *nd; 242 struct lwp *lwp; 243 { 244 struct ifnet *ifp = nd->nd_ifp; 245 int error; 246 247 /* 248 * Do enough of ifconfig(8) so that the chosen interface 249 * can talk to the servers. Use address zero for now. 250 */ 251 error = nfs_boot_setaddress(ifp, lwp, INADDR_ANY, INADDR_ANY, 252 INADDR_BROADCAST); 253 if (error) { 254 printf("nfs_boot: set ifaddr zero, error=%d\n", error); 255 return (error); 256 } 257 258 /* This function call does the real send/recv work. */ 259 error = bootpc_call(nd, lwp); 260 261 /* Get rid of the temporary (zero) IP address. */ 262 (void) nfs_boot_deladdress(ifp, lwp, INADDR_ANY); 263 264 /* NOW we can test the error from bootpc_call. */ 265 if (error) 266 goto out; 267 268 /* 269 * Do ifconfig with our real IP address and mask. 270 */ 271 error = nfs_boot_setaddress(ifp, lwp, nd->nd_myip.s_addr, 272 nd->nd_mask.s_addr, INADDR_ANY); 273 if (error) { 274 printf("nfs_boot: set ifaddr real, error=%d\n", error); 275 goto out; 276 } 277 278 out: 279 if (error) { 280 (void) nfs_boot_ifupdown(ifp, lwp, 0); 281 nfs_boot_flushrt(ifp); 282 } 283 return (error); 284 } 285 286 struct bootpcontext { 287 int xid; 288 u_char *haddr; 289 u_char halen; 290 struct bootp *replybuf; 291 int replylen; 292 #ifdef NFS_BOOT_DHCP 293 char expected_dhcpmsgtype, dhcp_ok; 294 struct in_addr dhcp_serverip; 295 #endif 296 }; 297 298 static int bootpset __P((struct mbuf*, void*, int)); 299 static int bootpcheck __P((struct mbuf*, void*)); 300 301 static int 302 bootpset(m, context, waited) 303 struct mbuf *m; 304 void *context; 305 int waited; 306 { 307 struct bootp *bootp; 308 309 /* we know it's contigous (in 1 mbuf cluster) */ 310 bootp = mtod(m, struct bootp*); 311 312 bootp->bp_secs = htons(waited); 313 314 return (0); 315 } 316 317 static int 318 bootpcheck(m, context) 319 struct mbuf *m; 320 void *context; 321 { 322 struct bootp *bootp; 323 struct bootpcontext *bpc = context; 324 u_int tag, len; 325 u_char *p, *limit; 326 327 /* 328 * Is this a valid reply? 329 */ 330 if (m->m_pkthdr.len < BOOTP_SIZE_MIN) { 331 DPRINTF(("bootpcheck: short packet %d < %d\n", m->m_pkthdr.len, 332 BOOTP_SIZE_MIN)); 333 return (-1); 334 } 335 if (m->m_pkthdr.len > BOOTP_SIZE_MAX) { 336 DPRINTF(("bootpcheck: long packet %d > %d\n", m->m_pkthdr.len, 337 BOOTP_SIZE_MAX)); 338 return (-1); 339 } 340 341 /* 342 * don't make first checks more expensive than necessary 343 */ 344 if (m->m_len < offsetof(struct bootp, bp_sname)) { 345 m = m_pullup(m, offsetof(struct bootp, bp_sname)); 346 if (m == NULL) { 347 DPRINTF(("bootpcheck: m_pullup failed\n")); 348 return (-1); 349 } 350 } 351 bootp = mtod(m, struct bootp*); 352 353 if (bootp->bp_op != BOOTREPLY) { 354 DPRINTF(("bootpcheck: op %d is not reply\n", bootp->bp_op)); 355 return (-1); 356 } 357 if (bootp->bp_hlen != bpc->halen) { 358 DPRINTF(("bootpcheck: hlen %d != %d\n", bootp->bp_hlen, 359 bpc->halen)); 360 return (-1); 361 } 362 if (memcmp(bootp->bp_chaddr, bpc->haddr, bpc->halen)) { 363 #ifdef DEBUG_NFS_BOOT_DHCP 364 char bp_chaddr[3 * bpc->halen], haddr[3 * bpc->halen]; 365 #endif 366 DPRINTF(("bootpcheck: incorrect hwaddr %s != %s\n", 367 ether_snprintf(bp_chaddr, sizeof(bp_chaddr), 368 bootp->bp_chaddr), 369 ether_snprintf(haddr, sizeof(haddr), bpc->haddr))); 370 return (-1); 371 } 372 if (bootp->bp_xid != bpc->xid) { 373 DPRINTF(("bootpcheck: xid %d != %d\n", bootp->bp_xid, 374 bpc->xid)); 375 return (-1); 376 } 377 378 /* 379 * OK, it's worth to look deeper. 380 * We copy the mbuf into a flat buffer here because 381 * m_pullup() is a bit limited for this purpose 382 * (doesn't allocate a cluster if necessary). 383 */ 384 bpc->replylen = m->m_pkthdr.len; 385 m_copydata(m, 0, bpc->replylen, (caddr_t)bpc->replybuf); 386 bootp = bpc->replybuf; 387 388 /* 389 * Check if the IP address we get looks correct. 390 * (DHCP servers can send junk to unknown clients.) 391 * XXX more checks might be needed 392 */ 393 if (bootp->bp_yiaddr.s_addr == INADDR_ANY || 394 bootp->bp_yiaddr.s_addr == INADDR_BROADCAST) { 395 printf("nfs_boot: wrong IP addr %s", 396 inet_ntoa(bootp->bp_yiaddr)); 397 goto warn; 398 } 399 400 /* 401 * Check the vendor data. 402 */ 403 if (memcmp(bootp->bp_vend, vm_rfc1048, 4)) { 404 printf("nfs_boot: reply missing options"); 405 goto warn; 406 } 407 p = &bootp->bp_vend[4]; 408 limit = ((char*)bootp) + bpc->replylen; 409 while (p < limit) { 410 tag = *p++; 411 if (tag == TAG_END) 412 break; 413 if (tag == TAG_PAD) 414 continue; 415 len = *p++; 416 if ((p + len) > limit) { 417 printf("nfs_boot: option %d too long", tag); 418 goto warn; 419 } 420 switch (tag) { 421 #ifdef NFS_BOOT_DHCP 422 case TAG_DHCP_MSGTYPE: 423 if (*p != bpc->expected_dhcpmsgtype) 424 return (-1); 425 bpc->dhcp_ok = 1; 426 break; 427 case TAG_SERVERID: 428 memcpy(&bpc->dhcp_serverip.s_addr, p, 429 sizeof(bpc->dhcp_serverip.s_addr)); 430 break; 431 #endif 432 default: 433 break; 434 } 435 p += len; 436 } 437 return (0); 438 439 warn: 440 printf(" (bad reply from %s)\n", inet_ntoa(bootp->bp_siaddr)); 441 return (-1); 442 } 443 444 static int 445 bootpc_call(nd, lwp) 446 struct nfs_diskless *nd; 447 struct lwp *lwp; 448 { 449 struct socket *so; 450 struct ifnet *ifp = nd->nd_ifp; 451 static u_int32_t xid = ~0xFF; 452 struct bootp *bootp; /* request */ 453 struct mbuf *m, *nam; 454 struct sockaddr_in *sin; 455 int error; 456 u_char *haddr; 457 u_char hafmt, halen; 458 struct bootpcontext bpc; 459 #ifdef NFS_BOOT_DHCP 460 char vci[64]; 461 int vcilen; 462 #endif 463 464 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp); 465 if (error) { 466 printf("bootp: socreate, error=%d\n", error); 467 return (error); 468 } 469 470 /* 471 * Initialize to NULL anything that will hold an allocation, 472 * and free each at the end if not null. 473 */ 474 bpc.replybuf = NULL; 475 m = nam = NULL; 476 477 /* Record our H/W (Ethernet) address. */ 478 { struct sockaddr_dl *sdl = ifp->if_sadl; 479 switch (sdl->sdl_type) { 480 case IFT_ISO88025: 481 hafmt = HTYPE_IEEE802; 482 break; 483 case IFT_ETHER: 484 case IFT_FDDI: 485 hafmt = HTYPE_ETHERNET; 486 break; 487 default: 488 printf("bootp: unsupported interface type %d\n", 489 sdl->sdl_type); 490 error = EINVAL; 491 goto out; 492 } 493 halen = sdl->sdl_alen; 494 haddr = (unsigned char *)LLADDR(sdl); 495 } 496 497 /* 498 * Skip the route table when sending on this socket. 499 * If this is not done, ip_output finds the loopback 500 * interface (why?) and then fails because broadcast 501 * is not supported on that interface... 502 */ 503 { int32_t *opt; 504 m = m_get(M_WAIT, MT_SOOPTS); 505 opt = mtod(m, int32_t *); 506 m->m_len = sizeof(*opt); 507 *opt = 1; 508 error = sosetopt(so, SOL_SOCKET, SO_DONTROUTE, m); 509 m = NULL; /* was consumed */ 510 } 511 if (error) { 512 DPRINTF(("bootpc_call: SO_DONTROUTE failed %d\n", error)); 513 goto out; 514 } 515 516 /* Enable broadcast. */ 517 if ((error = nfs_boot_enbroadcast(so))) { 518 DPRINTF(("bootpc_call: SO_BROADCAST failed %d\n", error)); 519 goto out; 520 } 521 522 /* 523 * Set some TTL so we can boot through routers. 524 * Real BOOTP forwarding agents don't need this; they obey "bp_hops" 525 * and set "bp_giaddr", thus rewrite the packet anyway. 526 * The "helper-address" feature of some popular router vendor seems 527 * to do simple IP forwarding and drops packets with (ip_ttl == 1). 528 */ 529 { u_char *opt; 530 m = m_get(M_WAIT, MT_SOOPTS); 531 opt = mtod(m, u_char *); 532 m->m_len = sizeof(*opt); 533 *opt = 7; 534 error = sosetopt(so, IPPROTO_IP, IP_MULTICAST_TTL, m); 535 m = NULL; /* was consumed */ 536 } 537 if (error) { 538 DPRINTF(("bootpc_call: IP_MULTICAST_TTL failed %d\n", error)); 539 goto out; 540 } 541 542 /* Set the receive timeout for the socket. */ 543 if ((error = nfs_boot_setrecvtimo(so))) { 544 DPRINTF(("bootpc_call: SO_RCVTIMEO failed %d\n", error)); 545 goto out; 546 } 547 548 /* 549 * Bind the local endpoint to a bootp client port. 550 */ 551 if ((error = nfs_boot_sobind_ipport(so, IPPORT_BOOTPC, lwp))) { 552 DPRINTF(("bootpc_call: bind failed %d\n", error)); 553 goto out; 554 } 555 556 /* 557 * Setup socket address for the server. 558 */ 559 nam = m_get(M_WAIT, MT_SONAME); 560 sin = mtod(nam, struct sockaddr_in *); 561 sin->sin_len = nam->m_len = sizeof(*sin); 562 sin->sin_family = AF_INET; 563 sin->sin_addr.s_addr = INADDR_BROADCAST; 564 sin->sin_port = htons(IPPORT_BOOTPS); 565 566 /* 567 * Allocate buffer used for request 568 */ 569 m = m_gethdr(M_WAIT, MT_DATA); 570 m_clget(m, M_WAIT); 571 bootp = mtod(m, struct bootp*); 572 m->m_pkthdr.len = m->m_len = BOOTP_SIZE_MAX; 573 m->m_pkthdr.rcvif = NULL; 574 575 /* 576 * Build the BOOTP reqest message. 577 * Note: xid is host order! (opaque to server) 578 */ 579 memset((caddr_t)bootp, 0, BOOTP_SIZE_MAX); 580 bootp->bp_op = BOOTREQUEST; 581 bootp->bp_htype = hafmt; 582 bootp->bp_hlen = halen; /* Hardware address length */ 583 bootp->bp_xid = ++xid; 584 memcpy(bootp->bp_chaddr, haddr, halen); 585 #ifdef NFS_BOOT_BOOTP_REQFILE 586 strncpy(bootp->bp_file, NFS_BOOT_BOOTP_REQFILE, sizeof(bootp->bp_file)); 587 #endif 588 /* Fill-in the vendor data. */ 589 memcpy(bootp->bp_vend, vm_rfc1048, 4); 590 #ifdef NFS_BOOT_DHCP 591 bootp->bp_vend[4] = TAG_DHCP_MSGTYPE; 592 bootp->bp_vend[5] = 1; 593 bootp->bp_vend[6] = DHCPDISCOVER; 594 /* 595 * Insert a NetBSD Vendor Class Identifier option. 596 */ 597 snprintf(vci, sizeof(vci), "%s:%s:kernel:%s", ostype, MACHINE, 598 osrelease); 599 vcilen = strlen(vci); 600 bootp->bp_vend[7] = TAG_CLASSID; 601 bootp->bp_vend[8] = vcilen; 602 memcpy(&bootp->bp_vend[9], vci, vcilen); 603 bootp->bp_vend[9 + vcilen] = TAG_END; 604 #else 605 bootp->bp_vend[4] = TAG_END; 606 #endif 607 608 bpc.xid = xid; 609 bpc.haddr = haddr; 610 bpc.halen = halen; 611 bpc.replybuf = malloc(BOOTP_SIZE_MAX, M_DEVBUF, M_WAITOK); 612 if (bpc.replybuf == NULL) 613 panic("nfs_boot: malloc reply buf"); 614 #ifdef NFS_BOOT_DHCP 615 bpc.expected_dhcpmsgtype = DHCPOFFER; 616 bpc.dhcp_ok = 0; 617 #endif 618 619 error = nfs_boot_sendrecv(so, nam, bootpset, m, 620 bootpcheck, 0, 0, &bpc, lwp); 621 if (error) 622 goto out; 623 624 #ifdef NFS_BOOT_DHCP 625 if (bpc.dhcp_ok) { 626 u_int32_t leasetime; 627 bootp->bp_vend[6] = DHCPREQUEST; 628 bootp->bp_vend[7] = TAG_REQ_ADDR; 629 bootp->bp_vend[8] = 4; 630 memcpy(&bootp->bp_vend[9], &bpc.replybuf->bp_yiaddr, 4); 631 bootp->bp_vend[13] = TAG_SERVERID; 632 bootp->bp_vend[14] = 4; 633 memcpy(&bootp->bp_vend[15], &bpc.dhcp_serverip.s_addr, 4); 634 bootp->bp_vend[19] = TAG_LEASETIME; 635 bootp->bp_vend[20] = 4; 636 leasetime = htonl(300); 637 memcpy(&bootp->bp_vend[21], &leasetime, 4); 638 bootp->bp_vend[25] = TAG_CLASSID; 639 bootp->bp_vend[26] = vcilen; 640 memcpy(&bootp->bp_vend[27], vci, vcilen); 641 bootp->bp_vend[27 + vcilen] = TAG_END; 642 643 bpc.expected_dhcpmsgtype = DHCPACK; 644 645 error = nfs_boot_sendrecv(so, nam, bootpset, m, 646 bootpcheck, 0, 0, &bpc, lwp); 647 if (error) 648 goto out; 649 } 650 #endif 651 652 /* 653 * bootpcheck() has copied the receive mbuf into 654 * the buffer at bpc.replybuf. 655 */ 656 #ifdef NFS_BOOT_DHCP 657 printf("nfs_boot: %s next-server: %s\n", 658 (bpc.dhcp_ok ? "DHCP" : "BOOTP"), 659 #else 660 printf("nfs_boot: BOOTP next-server: %s\n", 661 #endif 662 inet_ntoa(bpc.replybuf->bp_siaddr)); 663 664 bootp_extract(bpc.replybuf, bpc.replylen, nd); 665 666 out: 667 if (bpc.replybuf) 668 free(bpc.replybuf, M_DEVBUF); 669 if (m) 670 m_freem(m); 671 if (nam) 672 m_freem(nam); 673 soclose(so); 674 return (error); 675 } 676 677 static void 678 bootp_extract(bootp, replylen, nd) 679 struct bootp *bootp; 680 int replylen; 681 struct nfs_diskless *nd; 682 { 683 struct sockaddr_in *sin; 684 struct in_addr netmask; 685 struct in_addr gateway; 686 struct in_addr rootserver; 687 char *myname; /* my hostname */ 688 char *mydomain; /* my domainname */ 689 char *rootpath; 690 int mynamelen; 691 int mydomainlen; 692 int rootpathlen; 693 int overloaded; 694 u_int tag, len; 695 u_char *p, *limit; 696 697 /* Default these to "unspecified". */ 698 netmask.s_addr = 0; 699 gateway.s_addr = 0; 700 mydomain = myname = rootpath = NULL; 701 mydomainlen = mynamelen = rootpathlen = 0; 702 /* default root server to bootp next-server */ 703 rootserver = bootp->bp_siaddr; 704 /* assume that server name field is not overloaded by default */ 705 overloaded = 0; 706 707 p = &bootp->bp_vend[4]; 708 limit = ((char*)bootp) + replylen; 709 while (p < limit) { 710 tag = *p++; 711 if (tag == TAG_END) 712 break; 713 if (tag == TAG_PAD) 714 continue; 715 len = *p++; 716 #if 0 /* already done in bootpcheck() */ 717 if ((p + len) > limit) { 718 printf("nfs_boot: option %d too long\n", tag); 719 break; 720 } 721 #endif 722 switch (tag) { 723 case TAG_SUBNET_MASK: 724 memcpy(&netmask, p, 4); 725 break; 726 case TAG_GATEWAY: 727 /* Routers */ 728 memcpy(&gateway, p, 4); 729 break; 730 case TAG_HOST_NAME: 731 if (len >= sizeof(hostname)) { 732 printf("nfs_boot: host name >= %lu bytes", 733 (u_long)sizeof(hostname)); 734 break; 735 } 736 myname = p; 737 mynamelen = len; 738 break; 739 case TAG_DOMAIN_NAME: 740 if (len >= sizeof(domainname)) { 741 printf("nfs_boot: domain name >= %lu bytes", 742 (u_long)sizeof(domainname)); 743 break; 744 } 745 mydomain = p; 746 mydomainlen = len; 747 break; 748 case TAG_ROOT_PATH: 749 /* Leave some room for the server name. */ 750 if (len >= (MNAMELEN-10)) { 751 printf("nfs_boot: rootpath >=%d bytes", 752 (MNAMELEN-10)); 753 break; 754 } 755 rootpath = p; 756 rootpathlen = len; 757 break; 758 case TAG_SWAP_SERVER: 759 /* override NFS server address */ 760 memcpy(&rootserver, p, 4); 761 break; 762 #ifdef NFS_BOOT_DHCP 763 case TAG_OVERLOAD: 764 if (len > 0 && ((*p & 0x02) != 0)) 765 /* 766 * The server name field in the dhcp packet 767 * is overloaded and we can't find server 768 * name there. 769 */ 770 overloaded = 1; 771 break; 772 #endif 773 default: 774 break; 775 } 776 p += len; 777 } 778 779 /* 780 * Store and print network config info. 781 */ 782 if (myname) { 783 myname[mynamelen] = '\0'; 784 strncpy(hostname, myname, sizeof(hostname)); 785 hostnamelen = mynamelen; 786 printf("nfs_boot: my_name=%s\n", hostname); 787 } 788 if (mydomain) { 789 mydomain[mydomainlen] = '\0'; 790 strncpy(domainname, mydomain, sizeof(domainname)); 791 domainnamelen = mydomainlen; 792 printf("nfs_boot: my_domain=%s\n", domainname); 793 } 794 nd->nd_myip = bootp->bp_yiaddr; 795 if (nd->nd_myip.s_addr) 796 printf("nfs_boot: my_addr=%s\n", inet_ntoa(nd->nd_myip)); 797 nd->nd_mask = netmask; 798 if (nd->nd_mask.s_addr) 799 printf("nfs_boot: my_mask=%s\n", inet_ntoa(nd->nd_mask)); 800 nd->nd_gwip = gateway; 801 if (nd->nd_gwip.s_addr) 802 printf("nfs_boot: gateway=%s\n", inet_ntoa(nd->nd_gwip)); 803 804 /* 805 * Store the information about our NFS root mount. 806 * The caller will print it, so be silent here. 807 */ 808 { 809 struct nfs_dlmount *ndm = &nd->nd_root; 810 811 /* Server IP address. */ 812 sin = (struct sockaddr_in *) &ndm->ndm_saddr; 813 memset((caddr_t)sin, 0, sizeof(*sin)); 814 sin->sin_len = sizeof(*sin); 815 sin->sin_family = AF_INET; 816 sin->sin_addr = rootserver; 817 /* Server name. */ 818 if (!overloaded && bootp->bp_sname[0] != 0 && 819 !memcmp(&rootserver, &bootp->bp_siaddr, 820 sizeof(struct in_addr))) { 821 /* standard root server, we have the name */ 822 strncpy(ndm->ndm_host, bootp->bp_sname, BP_SNAME_LEN-1); 823 } else { 824 /* Show the server IP address numerically. */ 825 strncpy(ndm->ndm_host, inet_ntoa(rootserver), 826 BP_SNAME_LEN-1); 827 } 828 len = strlen(ndm->ndm_host); 829 if (rootpath && 830 len + 1 + rootpathlen + 1 <= sizeof(ndm->ndm_host)) { 831 ndm->ndm_host[len++] = ':'; 832 strncpy(ndm->ndm_host + len, 833 rootpath, rootpathlen); 834 ndm->ndm_host[len + rootpathlen] = '\0'; 835 } /* else: upper layer will handle error */ 836 } 837 } 838