1 /* $NetBSD: nfs_bootdhcp.c,v 1.52 2010/10/04 23:48:22 cyber 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Support for NFS diskless booting with BOOTP (RFC951, RFC1048) 34 * 35 * History: 36 * 37 * Tor Egge developed the initial version of this code based on 38 * the Sun RPC/bootparam sources nfs_boot.c and krpc_subr.c and 39 * submitted that work to NetBSD as bugreport "kern/2351" on 40 * 29 Apr 1996. 41 * 42 * Gordon Ross reorganized Tor's version into this form and 43 * integrated it into the NetBSD sources during Aug 1997. 44 */ 45 46 #include <sys/cdefs.h> 47 __KERNEL_RCSID(0, "$NetBSD: nfs_bootdhcp.c,v 1.52 2010/10/04 23:48:22 cyber Exp $"); 48 49 #ifdef _KERNEL_OPT 50 #include "opt_nfs_boot.h" 51 #include "opt_tftproot.h" 52 #endif 53 54 #include <sys/param.h> 55 #include <sys/systm.h> 56 #include <sys/kernel.h> 57 #include <sys/device.h> 58 #include <sys/ioctl.h> 59 #include <sys/proc.h> 60 #include <sys/mount.h> 61 #include <sys/mbuf.h> 62 #include <sys/reboot.h> 63 #include <sys/socket.h> 64 #include <sys/socketvar.h> 65 66 #include <net/if.h> 67 #include <net/if_types.h> 68 #include <net/if_arp.h> /* ARPHRD_ETHER, etc. */ 69 #include <net/if_dl.h> 70 #include <net/if_ether.h> 71 #include <net/route.h> 72 73 #include <netinet/in.h> 74 #include <netinet/if_inarp.h> 75 76 #include <nfs/rpcv2.h> 77 78 #include <nfs/nfsproto.h> 79 #include <nfs/nfs.h> 80 #include <nfs/nfsmount.h> 81 #include <nfs/nfsdiskless.h> 82 83 /* 84 * There are two implementations of NFS diskless boot. 85 * This implementation uses BOOTP (RFC951, RFC1048), and 86 * the other uses Sun RPC/bootparams (nfs_bootparam.c). 87 * 88 * This method gets everything it needs with one BOOTP 89 * request and reply. Note that this actually uses only 90 * the old BOOTP functionality subset of DHCP. It is not 91 * clear that DHCP provides any advantage over BOOTP for 92 * diskless boot. DHCP allows the server to assign an IP 93 * address without any a-priori knowledge of the client, 94 * but we require that the server has a-priori knowledge 95 * of the client so it can export our (unique) NFS root. 96 * Given that the server needs a-priori knowledge about 97 * the client anyway, it might as well assign a fixed IP 98 * address for the client and support BOOTP. 99 * 100 * On the other hand, disk-FULL clients may use DHCP, but 101 * in that case the DHCP client should be user-mode code, 102 * and has no bearing on the code below. -gwr 103 */ 104 105 /* Begin stuff from bootp.h */ 106 /* Definitions from RFC951 */ 107 #define BP_CHADDR_LEN 16 108 #define BP_SNAME_LEN 64 109 #define BP_FILE_LEN 128 110 #define BP_VEND_LEN 64 111 struct bootp { 112 u_int8_t bp_op; /* packet opcode type */ 113 u_int8_t bp_htype; /* hardware addr type */ 114 u_int8_t bp_hlen; /* hardware addr length */ 115 u_int8_t bp_hops; /* gateway hops */ 116 u_int32_t bp_xid; /* transaction ID */ 117 u_int16_t bp_secs; /* seconds since boot began */ 118 u_int16_t bp_flags; /* RFC1532 broadcast, etc. */ 119 struct in_addr bp_ciaddr; /* client IP address */ 120 struct in_addr bp_yiaddr; /* 'your' IP address */ 121 struct in_addr bp_siaddr; /* server IP address */ 122 struct in_addr bp_giaddr; /* gateway IP address */ 123 u_int8_t bp_chaddr[BP_CHADDR_LEN]; /* client hardware address */ 124 char bp_sname[BP_SNAME_LEN]; /* server host name */ 125 char bp_file[BP_FILE_LEN]; /* boot file name */ 126 u_int8_t bp_vend[BP_VEND_LEN]; /* RFC1048 options */ 127 /* 128 * Note that BOOTP packets are allowed to be longer 129 * (see RFC 1532 sect. 2.1) and common practice is to 130 * allow the option data in bp_vend to extend into the 131 * additional space provided in longer packets. 132 */ 133 }; 134 135 #define IPPORT_BOOTPS 67 136 #define IPPORT_BOOTPC 68 137 138 #define BOOTREQUEST 1 139 #define BOOTREPLY 2 140 141 /* 142 * Is this available from the sockaddr_dl somehow? 143 * Perhaps (struct arphdr)->ar_hrd = ARPHRD_ETHER? 144 * The interface has ->if_type but not the ARP fmt. 145 */ 146 #define HTYPE_ETHERNET 1 147 #define HTYPE_IEEE802 6 148 149 /* 150 * Vendor magic cookie (v_magic) for RFC1048 151 */ 152 static const u_int8_t vm_rfc1048[4] = { 99, 130, 83, 99 }; 153 154 /* 155 * Tag values used to specify what information is being supplied in 156 * the vendor (options) data area of the packet. 157 */ 158 /* RFC 1048 */ 159 #define TAG_END ((unsigned char) 255) 160 #define TAG_PAD ((unsigned char) 0) 161 #define TAG_SUBNET_MASK ((unsigned char) 1) 162 #define TAG_TIME_OFFSET ((unsigned char) 2) 163 #define TAG_GATEWAY ((unsigned char) 3) 164 #define TAG_TIME_SERVER ((unsigned char) 4) 165 #define TAG_NAME_SERVER ((unsigned char) 5) 166 #define TAG_DOMAIN_SERVER ((unsigned char) 6) 167 #define TAG_LOG_SERVER ((unsigned char) 7) 168 #define TAG_COOKIE_SERVER ((unsigned char) 8) 169 #define TAG_LPR_SERVER ((unsigned char) 9) 170 #define TAG_IMPRESS_SERVER ((unsigned char) 10) 171 #define TAG_RLP_SERVER ((unsigned char) 11) 172 #define TAG_HOST_NAME ((unsigned char) 12) 173 #define TAG_BOOT_SIZE ((unsigned char) 13) 174 /* RFC 1395 */ 175 #define TAG_DUMP_FILE ((unsigned char) 14) 176 #define TAG_DOMAIN_NAME ((unsigned char) 15) 177 #define TAG_SWAP_SERVER ((unsigned char) 16) 178 #define TAG_ROOT_PATH ((unsigned char) 17) 179 /* RFC 2132 */ 180 #define TAG_INTERFACE_MTU ((unsigned char) 26) 181 /* End of stuff from bootp.h */ 182 183 #ifdef NFS_BOOT_DHCP 184 #define TAG_REQ_ADDR ((unsigned char) 50) 185 #define TAG_LEASETIME ((unsigned char) 51) 186 #define TAG_OVERLOAD ((unsigned char) 52) 187 #define TAG_DHCP_MSGTYPE ((unsigned char) 53) 188 #define TAG_SERVERID ((unsigned char) 54) 189 #define TAG_PARAM_REQ ((unsigned char) 55) 190 #define TAG_MSG ((unsigned char) 56) 191 #define TAG_MAXSIZE ((unsigned char) 57) 192 #define TAG_T1 ((unsigned char) 58) 193 #define TAG_T2 ((unsigned char) 59) 194 #define TAG_CLASSID ((unsigned char) 60) 195 #define TAG_CLIENTID ((unsigned char) 61) 196 #endif 197 198 #ifdef NFS_BOOT_DHCP 199 #define DHCPDISCOVER 1 200 #define DHCPOFFER 2 201 #define DHCPREQUEST 3 202 #define DHCPDECLINE 4 203 #define DHCPACK 5 204 #define DHCPNAK 6 205 #define DHCPRELEASE 7 206 #endif 207 208 #define IP_MIN_MTU 576 209 210 #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 (struct nfs_diskless *, struct lwp *, int *); 227 static void bootp_extract (struct bootp *, int, struct nfs_diskless *, int *); 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(struct nfs_diskless *nd, struct lwp *lwp, int *flags) 241 { 242 struct ifnet *ifp = nd->nd_ifp; 243 int error; 244 245 /* 246 * Do enough of ifconfig(8) so that the chosen interface 247 * can talk to the servers. Use address zero for now. 248 */ 249 error = nfs_boot_setaddress(ifp, lwp, 250 *flags & NFS_BOOT_HAS_MYIP ? nd->nd_myip.s_addr : INADDR_ANY, 251 *flags & NFS_BOOT_HAS_MASK ? nd->nd_mask.s_addr : 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, flags); 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 if ((*flags & NFS_BOOT_ALLINFO) != NFS_BOOT_ALLINFO) { 279 printf("nfs_boot: missing options (need IP, netmask, " 280 "gateway, next-server, root-path)\n"); 281 return EADDRNOTAVAIL; 282 } 283 284 out: 285 if (error) { 286 (void) nfs_boot_ifupdown(ifp, lwp, 0); 287 nfs_boot_flushrt(ifp); 288 } 289 return (error); 290 } 291 292 struct bootpcontext { 293 int xid; 294 const u_char *haddr; 295 u_char halen; 296 struct bootp *replybuf; 297 int replylen; 298 #ifdef NFS_BOOT_DHCP 299 char expected_dhcpmsgtype, dhcp_ok; 300 struct in_addr dhcp_serverip; 301 #endif 302 }; 303 304 static int bootpset (struct mbuf*, void*, int); 305 static int bootpcheck (struct mbuf*, void*); 306 307 static int 308 bootpset(struct mbuf *m, void *context, int waited) 309 { 310 struct bootp *bootp; 311 312 /* we know it's contigous (in 1 mbuf cluster) */ 313 bootp = mtod(m, struct bootp*); 314 315 bootp->bp_secs = htons(waited); 316 317 return (0); 318 } 319 320 static int 321 bootpcheck(struct mbuf *m, void *context) 322 { 323 struct bootp *bootp; 324 struct bootpcontext *bpc = context; 325 u_int tag, len; 326 u_char *p, *limit; 327 328 /* 329 * Is this a valid reply? 330 */ 331 if (m->m_pkthdr.len < BOOTP_SIZE_MIN) { 332 DPRINTF(("bootpcheck: short packet %d < %zu\n", 333 m->m_pkthdr.len, BOOTP_SIZE_MIN)); 334 return (-1); 335 } 336 if (m->m_pkthdr.len > BOOTP_SIZE_MAX) { 337 DPRINTF(("Bootpcheck: long packet %d > %zu\n", 338 m->m_pkthdr.len, BOOTP_SIZE_MAX)); 339 return (-1); 340 } 341 342 /* 343 * don't make first checks more expensive than necessary 344 */ 345 if (m->m_len < offsetof(struct bootp, bp_sname)) { 346 m = m_pullup(m, offsetof(struct bootp, bp_sname)); 347 if (m == NULL) { 348 DPRINTF(("bootpcheck: m_pullup failed\n")); 349 return (-1); 350 } 351 } 352 bootp = mtod(m, struct bootp*); 353 354 if (bootp->bp_op != BOOTREPLY) { 355 DPRINTF(("bootpcheck: op %d is not reply\n", bootp->bp_op)); 356 return (-1); 357 } 358 if (bootp->bp_hlen != bpc->halen) { 359 DPRINTF(("bootpcheck: hlen %d != %d\n", bootp->bp_hlen, 360 bpc->halen)); 361 return (-1); 362 } 363 if (memcmp(bootp->bp_chaddr, bpc->haddr, bpc->halen)) { 364 #ifdef DEBUG_NFS_BOOT_DHCP 365 char *bp_chaddr, *haddr; 366 367 bp_chaddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 368 haddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 369 370 DPRINTF(("bootpcheck: incorrect hwaddr %s != %s\n", 371 ether_snprintf(bp_chaddr, 3 * bpc->halen, 372 bootp->bp_chaddr), 373 ether_snprintf(haddr, 3 * bpc->halen, bpc->haddr))); 374 375 free(bp_chaddr, M_TEMP); 376 free(haddr, M_TEMP); 377 #endif 378 return (-1); 379 } 380 if (bootp->bp_xid != bpc->xid) { 381 DPRINTF(("bootpcheck: xid %d != %d\n", bootp->bp_xid, 382 bpc->xid)); 383 return (-1); 384 } 385 386 /* 387 * OK, it's worth to look deeper. 388 * We copy the mbuf into a flat buffer here because 389 * m_pullup() is a bit limited for this purpose 390 * (doesn't allocate a cluster if necessary). 391 */ 392 bpc->replylen = m->m_pkthdr.len; 393 m_copydata(m, 0, bpc->replylen, (void *)bpc->replybuf); 394 bootp = bpc->replybuf; 395 396 /* 397 * Check if the IP address we get looks correct. 398 * (DHCP servers can send junk to unknown clients.) 399 * XXX more checks might be needed 400 */ 401 if (bootp->bp_yiaddr.s_addr == INADDR_ANY || 402 bootp->bp_yiaddr.s_addr == INADDR_BROADCAST) { 403 printf("nfs_boot: wrong IP addr %s", 404 inet_ntoa(bootp->bp_yiaddr)); 405 goto warn; 406 } 407 408 /* 409 * Check the vendor data. 410 */ 411 if (memcmp(bootp->bp_vend, vm_rfc1048, 4)) { 412 printf("nfs_boot: reply missing options"); 413 goto warn; 414 } 415 p = &bootp->bp_vend[4]; 416 limit = ((u_char*)bootp) + bpc->replylen; 417 while (p < limit) { 418 tag = *p++; 419 if (tag == TAG_END) 420 break; 421 if (tag == TAG_PAD) 422 continue; 423 len = *p++; 424 if ((p + len) > limit) { 425 printf("nfs_boot: option %d too long", tag); 426 goto warn; 427 } 428 switch (tag) { 429 #ifdef NFS_BOOT_DHCP 430 case TAG_DHCP_MSGTYPE: 431 if (*p != bpc->expected_dhcpmsgtype) 432 return (-1); 433 bpc->dhcp_ok = 1; 434 break; 435 case TAG_SERVERID: 436 memcpy(&bpc->dhcp_serverip.s_addr, p, 437 sizeof(bpc->dhcp_serverip.s_addr)); 438 break; 439 #endif 440 default: 441 break; 442 } 443 p += len; 444 } 445 return (0); 446 447 warn: 448 printf(" (bad reply from %s)\n", inet_ntoa(bootp->bp_siaddr)); 449 return (-1); 450 } 451 452 static void 453 bootp_addvend(u_char *area) 454 { 455 #ifdef NFS_BOOT_DHCP 456 char vci[64]; 457 int vcilen; 458 459 *area++ = TAG_PARAM_REQ; 460 *area++ = 7; 461 *area++ = TAG_SUBNET_MASK; 462 *area++ = TAG_GATEWAY; 463 *area++ = TAG_HOST_NAME; 464 *area++ = TAG_DOMAIN_NAME; 465 *area++ = TAG_ROOT_PATH; 466 *area++ = TAG_SWAP_SERVER; 467 *area++ = TAG_INTERFACE_MTU; 468 469 /* Insert a NetBSD Vendor Class Identifier option. */ 470 snprintf(vci, sizeof(vci), "%s:%s:kernel:%s", ostype, MACHINE, 471 osrelease); 472 vcilen = strlen(vci); 473 *area++ = TAG_CLASSID; 474 *area++ = vcilen; 475 (void)memcpy(area, vci, vcilen); 476 area += vcilen; 477 #endif 478 *area = TAG_END; 479 } 480 481 static int 482 bootpc_call(struct nfs_diskless *nd, struct lwp *lwp, int *flags) 483 { 484 struct socket *so; 485 struct ifnet *ifp = nd->nd_ifp; 486 static u_int32_t xid = ~0xFF; 487 struct bootp *bootp; /* request */ 488 struct mbuf *m, *nam; 489 struct sockaddr_in *sin; 490 int error; 491 const u_char *haddr; 492 u_char hafmt, halen; 493 struct bootpcontext bpc; 494 unsigned int index; 495 496 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 497 if (error) { 498 printf("bootp: socreate, error=%d\n", error); 499 return (error); 500 } 501 502 /* 503 * Initialize to NULL anything that will hold an allocation, 504 * and free each at the end if not null. 505 */ 506 bpc.replybuf = NULL; 507 m = nam = NULL; 508 509 /* Record our H/W (Ethernet) address. */ 510 { const struct sockaddr_dl *sdl = ifp->if_sadl; 511 switch (sdl->sdl_type) { 512 case IFT_ISO88025: 513 hafmt = HTYPE_IEEE802; 514 break; 515 case IFT_ETHER: 516 case IFT_FDDI: 517 hafmt = HTYPE_ETHERNET; 518 break; 519 default: 520 printf("bootp: unsupported interface type %d\n", 521 sdl->sdl_type); 522 error = EINVAL; 523 goto out; 524 } 525 halen = sdl->sdl_alen; 526 haddr = (const unsigned char *)CLLADDR(sdl); 527 } 528 529 /* 530 * Skip the route table when sending on this socket. 531 * If this is not done, ip_output finds the loopback 532 * interface (why?) and then fails because broadcast 533 * is not supported on that interface... 534 */ 535 { int32_t opt; 536 537 opt = 1; 538 error = so_setsockopt(NULL, so, SOL_SOCKET, SO_DONTROUTE, &opt, 539 sizeof(opt)); 540 } 541 if (error) { 542 DPRINTF(("bootpc_call: SO_DONTROUTE failed %d\n", error)); 543 goto out; 544 } 545 546 /* Enable broadcast. */ 547 if ((error = nfs_boot_enbroadcast(so))) { 548 DPRINTF(("bootpc_call: SO_BROADCAST failed %d\n", error)); 549 goto out; 550 } 551 552 /* 553 * Set some TTL so we can boot through routers. 554 * Real BOOTP forwarding agents don't need this; they obey "bp_hops" 555 * and set "bp_giaddr", thus rewrite the packet anyway. 556 * The "helper-address" feature of some popular router vendor seems 557 * to do simple IP forwarding and drops packets with (ip_ttl == 1). 558 */ 559 { u_char opt; 560 561 opt = 7; 562 error = so_setsockopt(NULL, so, IPPROTO_IP, IP_MULTICAST_TTL, 563 &opt, sizeof(opt)); 564 } 565 if (error) { 566 DPRINTF(("bootpc_call: IP_MULTICAST_TTL failed %d\n", error)); 567 goto out; 568 } 569 570 /* Set the receive timeout for the socket. */ 571 if ((error = nfs_boot_setrecvtimo(so))) { 572 DPRINTF(("bootpc_call: SO_RCVTIMEO failed %d\n", error)); 573 goto out; 574 } 575 576 /* 577 * Bind the local endpoint to a bootp client port. 578 */ 579 if ((error = nfs_boot_sobind_ipport(so, IPPORT_BOOTPC, lwp))) { 580 DPRINTF(("bootpc_call: bind failed %d\n", error)); 581 goto out; 582 } 583 584 /* 585 * Setup socket address for the server. 586 */ 587 nam = m_get(M_WAIT, MT_SONAME); 588 sin = mtod(nam, struct sockaddr_in *); 589 sin->sin_len = nam->m_len = sizeof(*sin); 590 sin->sin_family = AF_INET; 591 sin->sin_addr.s_addr = INADDR_BROADCAST; 592 sin->sin_port = htons(IPPORT_BOOTPS); 593 594 /* 595 * Allocate buffer used for request 596 */ 597 m = m_gethdr(M_WAIT, MT_DATA); 598 m_clget(m, M_WAIT); 599 bootp = mtod(m, struct bootp*); 600 m->m_pkthdr.len = m->m_len = BOOTP_SIZE_MAX; 601 m->m_pkthdr.rcvif = NULL; 602 603 /* 604 * Build the BOOTP reqest message. 605 * Note: xid is host order! (opaque to server) 606 */ 607 memset((void *)bootp, 0, BOOTP_SIZE_MAX); 608 bootp->bp_op = BOOTREQUEST; 609 bootp->bp_htype = hafmt; 610 bootp->bp_hlen = halen; /* Hardware address length */ 611 bootp->bp_xid = ++xid; 612 memcpy(bootp->bp_chaddr, haddr, halen); 613 #ifdef NFS_BOOT_BOOTP_REQFILE 614 strncpy(bootp->bp_file, NFS_BOOT_BOOTP_REQFILE, sizeof(bootp->bp_file)); 615 #endif 616 /* Fill-in the vendor data. */ 617 memcpy(bootp->bp_vend, vm_rfc1048, 4); 618 index = 4; 619 #ifdef NFS_BOOT_DHCP 620 bootp->bp_vend[index++] = TAG_DHCP_MSGTYPE; 621 bootp->bp_vend[index++] = 1; 622 bootp->bp_vend[index++] = DHCPDISCOVER; 623 #endif 624 bootp_addvend(&bootp->bp_vend[index]); 625 626 bpc.xid = xid; 627 bpc.haddr = haddr; 628 bpc.halen = halen; 629 bpc.replybuf = malloc(BOOTP_SIZE_MAX, M_DEVBUF, M_WAITOK); 630 if (bpc.replybuf == NULL) 631 panic("nfs_boot: malloc reply buf"); 632 #ifdef NFS_BOOT_DHCP 633 bpc.expected_dhcpmsgtype = DHCPOFFER; 634 bpc.dhcp_ok = 0; 635 #endif 636 637 error = nfs_boot_sendrecv(so, nam, bootpset, m, 638 bootpcheck, 0, 0, &bpc, lwp); 639 if (error) 640 goto out; 641 642 #ifdef NFS_BOOT_DHCP 643 if (bpc.dhcp_ok) { 644 u_int32_t leasetime; 645 index = 6; 646 bootp->bp_vend[index++] = DHCPREQUEST; 647 bootp->bp_vend[index++] = TAG_REQ_ADDR; 648 bootp->bp_vend[index++] = 4; 649 memcpy(&bootp->bp_vend[index], &bpc.replybuf->bp_yiaddr, 4); 650 index += 4; 651 bootp->bp_vend[index++] = TAG_SERVERID; 652 bootp->bp_vend[index++] = 4; 653 memcpy(&bootp->bp_vend[index], &bpc.dhcp_serverip.s_addr, 4); 654 index += 4; 655 bootp->bp_vend[index++] = TAG_LEASETIME; 656 bootp->bp_vend[index++] = 4; 657 leasetime = htonl(300); 658 memcpy(&bootp->bp_vend[index], &leasetime, 4); 659 index += 4; 660 bootp_addvend(&bootp->bp_vend[index]); 661 662 bpc.expected_dhcpmsgtype = DHCPACK; 663 664 error = nfs_boot_sendrecv(so, nam, bootpset, m, 665 bootpcheck, 0, 0, &bpc, lwp); 666 if (error) 667 goto out; 668 } 669 #endif 670 671 /* 672 * bootpcheck() has copied the receive mbuf into 673 * the buffer at bpc.replybuf. 674 */ 675 #ifdef NFS_BOOT_DHCP 676 printf("nfs_boot: %s next-server: %s\n", 677 (bpc.dhcp_ok ? "DHCP" : "BOOTP"), 678 #else 679 printf("nfs_boot: BOOTP next-server: %s\n", 680 #endif 681 inet_ntoa(bpc.replybuf->bp_siaddr)); 682 683 bootp_extract(bpc.replybuf, bpc.replylen, nd, flags); 684 685 out: 686 if (bpc.replybuf) 687 free(bpc.replybuf, M_DEVBUF); 688 if (m) 689 m_freem(m); 690 if (nam) 691 m_freem(nam); 692 soclose(so); 693 return (error); 694 } 695 696 static void 697 bootp_extract(struct bootp *bootp, int replylen, 698 struct nfs_diskless *nd, int *flags) 699 { 700 struct sockaddr_in *sin; 701 struct in_addr netmask; 702 struct in_addr gateway; 703 struct in_addr rootserver; 704 char *myname; /* my hostname */ 705 char *mydomain; /* my domainname */ 706 char *rootpath; 707 uint16_t myinterfacemtu; 708 int mynamelen; 709 int mydomainlen; 710 int rootpathlen; 711 int overloaded; 712 u_int tag, len; 713 u_char *p, *limit; 714 715 /* Default these to "unspecified". */ 716 netmask.s_addr = 0; 717 gateway.s_addr = 0; 718 mydomain = myname = rootpath = NULL; 719 mydomainlen = mynamelen = rootpathlen = 0; 720 721 /* default root server to bootp next-server */ 722 rootserver = bootp->bp_siaddr; 723 /* assume that server name field is not overloaded by default */ 724 overloaded = 0; 725 /* MTU can't be less than IP_MIN_MTU, set to 0 to indicate unset */ 726 myinterfacemtu = 0; 727 728 p = &bootp->bp_vend[4]; 729 limit = ((u_char*)bootp) + replylen; 730 while (p < limit) { 731 tag = *p++; 732 if (tag == TAG_END) 733 break; 734 if (tag == TAG_PAD) 735 continue; 736 len = *p++; 737 #if 0 /* already done in bootpcheck() */ 738 if ((p + len) > limit) { 739 printf("nfs_boot: option %d too long\n", tag); 740 break; 741 } 742 #endif 743 switch (tag) { 744 case TAG_SUBNET_MASK: 745 if (len < 4) { 746 printf("nfs_boot: subnet mask < 4 bytes\n"); 747 break; 748 } 749 memcpy(&netmask, p, 4); 750 break; 751 case TAG_GATEWAY: 752 /* Routers */ 753 if (len < 4) { 754 printf("nfs_boot: routers < 4 bytes\n"); 755 break; 756 } 757 memcpy(&gateway, p, 4); 758 break; 759 case TAG_HOST_NAME: 760 if (len >= sizeof(hostname)) { 761 printf("nfs_boot: host name >= %lu bytes\n", 762 (u_long)sizeof(hostname)); 763 break; 764 } 765 myname = p; 766 mynamelen = len; 767 break; 768 case TAG_DOMAIN_NAME: 769 if (len >= sizeof(domainname)) { 770 printf("nfs_boot: domain name >= %lu bytes\n", 771 (u_long)sizeof(domainname)); 772 break; 773 } 774 mydomain = p; 775 mydomainlen = len; 776 break; 777 case TAG_ROOT_PATH: 778 /* Leave some room for the server name. */ 779 if (len >= (MNAMELEN-10)) { 780 printf("nfs_boot: rootpath >= %d bytes\n", 781 (MNAMELEN-10)); 782 break; 783 } 784 rootpath = p; 785 rootpathlen = len; 786 break; 787 case TAG_INTERFACE_MTU: 788 if (len != 2) { 789 printf("nfs_boot: interface-mtu len != 2 (%d)", 790 len); 791 break; 792 } 793 memcpy(&myinterfacemtu, p, 2); 794 myinterfacemtu = ntohs(myinterfacemtu); 795 break; 796 case TAG_SWAP_SERVER: 797 /* override NFS server address */ 798 if (len < 4) { 799 printf("nfs_boot: swap server < 4 bytes\n"); 800 break; 801 } 802 memcpy(&rootserver, p, 4); 803 break; 804 #ifdef NFS_BOOT_DHCP 805 case TAG_OVERLOAD: 806 if (len > 0 && ((*p & 0x02) != 0)) 807 /* 808 * The server name field in the dhcp packet 809 * is overloaded and we can't find server 810 * name there. 811 */ 812 overloaded = 1; 813 break; 814 #endif 815 default: 816 break; 817 } 818 p += len; 819 } 820 821 /* 822 * Store and print network config info. 823 */ 824 if (myname) { 825 myname[mynamelen] = '\0'; 826 strncpy(hostname, myname, sizeof(hostname)); 827 hostnamelen = mynamelen; 828 printf("nfs_boot: my_name=%s\n", hostname); 829 } 830 if (mydomain) { 831 mydomain[mydomainlen] = '\0'; 832 strncpy(domainname, mydomain, sizeof(domainname)); 833 domainnamelen = mydomainlen; 834 printf("nfs_boot: my_domain=%s\n", domainname); 835 } 836 if (!(*flags & NFS_BOOT_HAS_MYIP)) { 837 nd->nd_myip = bootp->bp_yiaddr; 838 printf("nfs_boot: my_addr=%s\n", inet_ntoa(nd->nd_myip)); 839 *flags |= NFS_BOOT_HAS_MYIP; 840 } 841 if (!(*flags & NFS_BOOT_HAS_MASK)) { 842 nd->nd_mask = netmask; 843 printf("nfs_boot: my_mask=%s\n", inet_ntoa(nd->nd_mask)); 844 *flags |= NFS_BOOT_HAS_MASK; 845 } 846 if (!(*flags & NFS_BOOT_HAS_GWIP)) { 847 nd->nd_gwip = gateway; 848 printf("nfs_boot: gateway=%s\n", inet_ntoa(nd->nd_gwip)); 849 *flags |= NFS_BOOT_HAS_GWIP; 850 } 851 if (myinterfacemtu >= IP_MIN_MTU) { 852 nd->nd_mtu = myinterfacemtu; 853 printf("nfs_boot: mtu=%d\n", nd->nd_mtu); 854 } 855 856 /* 857 * Store the information about our NFS root mount. 858 * The caller will print it, so be silent here. 859 */ 860 do { 861 struct nfs_dlmount *ndm = &nd->nd_root; 862 863 864 if (!(*flags & NFS_BOOT_HAS_SERVADDR)) { 865 /* Server IP address. */ 866 sin = (struct sockaddr_in *) &ndm->ndm_saddr; 867 memset((void *)sin, 0, sizeof(*sin)); 868 sin->sin_len = sizeof(*sin); 869 sin->sin_family = AF_INET; 870 sin->sin_addr = rootserver; 871 *flags |= NFS_BOOT_HAS_SERVADDR; 872 } 873 874 if (!(*flags & NFS_BOOT_HAS_SERVER)) { 875 /* Server name. */ 876 if (!overloaded && bootp->bp_sname[0] != 0 && 877 !memcmp(&rootserver, &bootp->bp_siaddr, 878 sizeof(struct in_addr))) 879 { 880 /* standard root server, we have the name */ 881 strncpy(ndm->ndm_host, bootp->bp_sname, 882 BP_SNAME_LEN-1); 883 *flags |= NFS_BOOT_HAS_SERVER; 884 } else { 885 /* Show the server IP address numerically. */ 886 strncpy(ndm->ndm_host, inet_ntoa(rootserver), 887 BP_SNAME_LEN-1); 888 *flags |= NFS_BOOT_HAS_SERVER; 889 } 890 } 891 892 if (!(*flags & NFS_BOOT_HAS_ROOTPATH)) { 893 len = strlen(ndm->ndm_host); 894 if (rootpath && 895 len + 1 + rootpathlen + 1 <= sizeof(ndm->ndm_host)) 896 { 897 ndm->ndm_host[len++] = ':'; 898 strncpy(ndm->ndm_host + len, 899 rootpath, rootpathlen); 900 ndm->ndm_host[len + rootpathlen] = '\0'; 901 *flags |= NFS_BOOT_HAS_ROOTPATH; 902 } /* else: upper layer will handle error */ 903 } 904 } while(0); 905 906 #ifdef TFTPROOT 907 #if BP_FILE_LEN > MNAMELEN 908 #define BOOTFILELEN MNAMELEN 909 #else 910 #define BOOTFILELEN BP_FILE_LEN 911 #endif 912 strncpy(nd->nd_bootfile, bootp->bp_file, BOOTFILELEN); 913 nd->nd_bootfile[BOOTFILELEN - 1] = '\0'; 914 #undef BOOTFILELEN 915 #endif /* TFTPROOT */ 916 } 917