1 /* $NetBSD: nfs_bootdhcp.c,v 1.48 2009/05/06 05:34:12 cegger 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 1.48 2009/05/06 05:34:12 cegger 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 /* End of stuff from bootp.h */ 180 181 #ifdef NFS_BOOT_DHCP 182 #define TAG_REQ_ADDR ((unsigned char) 50) 183 #define TAG_LEASETIME ((unsigned char) 51) 184 #define TAG_OVERLOAD ((unsigned char) 52) 185 #define TAG_DHCP_MSGTYPE ((unsigned char) 53) 186 #define TAG_SERVERID ((unsigned char) 54) 187 #define TAG_PARAM_REQ ((unsigned char) 55) 188 #define TAG_MSG ((unsigned char) 56) 189 #define TAG_MAXSIZE ((unsigned char) 57) 190 #define TAG_T1 ((unsigned char) 58) 191 #define TAG_T2 ((unsigned char) 59) 192 #define TAG_CLASSID ((unsigned char) 60) 193 #define TAG_CLIENTID ((unsigned char) 61) 194 #endif 195 196 #ifdef NFS_BOOT_DHCP 197 #define DHCPDISCOVER 1 198 #define DHCPOFFER 2 199 #define DHCPREQUEST 3 200 #define DHCPDECLINE 4 201 #define DHCPACK 5 202 #define DHCPNAK 6 203 #define DHCPRELEASE 7 204 #endif 205 206 #ifdef NFS_BOOT_DHCP 207 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+312-64) 208 #else 209 /* 210 * The "extended" size is somewhat arbitrary, but is 211 * constrained by the maximum message size specified 212 * by RFC1533 (567 total). This value increases the 213 * space for options from 64 bytes to 256 bytes. 214 */ 215 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+256-64) 216 #endif 217 #define BOOTP_SIZE_MIN (sizeof(struct bootp)) 218 219 /* Convenience macro */ 220 #define INTOHL(ina) ((u_int32_t)ntohl((ina).s_addr)) 221 222 static int bootpc_call (struct nfs_diskless *, struct lwp *, int *); 223 static void bootp_extract (struct bootp *, int, struct nfs_diskless *, int *); 224 225 #ifdef DEBUG_NFS_BOOT_DHCP 226 #define DPRINTF(s) printf s 227 #else 228 #define DPRINTF(s) 229 #endif 230 231 232 /* 233 * Get our boot parameters using BOOTP. 234 */ 235 int 236 nfs_bootdhcp(struct nfs_diskless *nd, struct lwp *lwp, int *flags) 237 { 238 struct ifnet *ifp = nd->nd_ifp; 239 int error; 240 241 /* 242 * Do enough of ifconfig(8) so that the chosen interface 243 * can talk to the servers. Use address zero for now. 244 */ 245 error = nfs_boot_setaddress(ifp, lwp, 246 *flags & NFS_BOOT_HAS_MYIP ? nd->nd_myip.s_addr : INADDR_ANY, 247 *flags & NFS_BOOT_HAS_MASK ? nd->nd_mask.s_addr : INADDR_ANY, 248 INADDR_BROADCAST); 249 if (error) { 250 printf("nfs_boot: set ifaddr zero, error=%d\n", error); 251 return (error); 252 } 253 254 /* This function call does the real send/recv work. */ 255 error = bootpc_call(nd, lwp, flags); 256 257 /* Get rid of the temporary (zero) IP address. */ 258 (void) nfs_boot_deladdress(ifp, lwp, INADDR_ANY); 259 260 /* NOW we can test the error from bootpc_call. */ 261 if (error) 262 goto out; 263 264 /* 265 * Do ifconfig with our real IP address and mask. 266 */ 267 error = nfs_boot_setaddress(ifp, lwp, nd->nd_myip.s_addr, 268 nd->nd_mask.s_addr, INADDR_ANY); 269 if (error) { 270 printf("nfs_boot: set ifaddr real, error=%d\n", error); 271 goto out; 272 } 273 274 if ((*flags & NFS_BOOT_ALLINFO) != NFS_BOOT_ALLINFO) { 275 printf("nfs_boot: missing options (need IP, netmask, " 276 "gateway, next-server, root-path)\n"); 277 return EADDRNOTAVAIL; 278 } 279 280 out: 281 if (error) { 282 (void) nfs_boot_ifupdown(ifp, lwp, 0); 283 nfs_boot_flushrt(ifp); 284 } 285 return (error); 286 } 287 288 struct bootpcontext { 289 int xid; 290 const 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 (struct mbuf*, void*, int); 301 static int bootpcheck (struct mbuf*, void*); 302 303 static int 304 bootpset(struct mbuf *m, void *context, int waited) 305 { 306 struct bootp *bootp; 307 308 /* we know it's contigous (in 1 mbuf cluster) */ 309 bootp = mtod(m, struct bootp*); 310 311 bootp->bp_secs = htons(waited); 312 313 return (0); 314 } 315 316 static int 317 bootpcheck(struct mbuf *m, void *context) 318 { 319 struct bootp *bootp; 320 struct bootpcontext *bpc = context; 321 u_int tag, len; 322 u_char *p, *limit; 323 324 /* 325 * Is this a valid reply? 326 */ 327 if (m->m_pkthdr.len < BOOTP_SIZE_MIN) { 328 DPRINTF(("bootpcheck: short packet %d < %zu\n", 329 m->m_pkthdr.len, BOOTP_SIZE_MIN)); 330 return (-1); 331 } 332 if (m->m_pkthdr.len > BOOTP_SIZE_MAX) { 333 DPRINTF(("Bootpcheck: long packet %d > %zu\n", 334 m->m_pkthdr.len, BOOTP_SIZE_MAX)); 335 return (-1); 336 } 337 338 /* 339 * don't make first checks more expensive than necessary 340 */ 341 if (m->m_len < offsetof(struct bootp, bp_sname)) { 342 m = m_pullup(m, offsetof(struct bootp, bp_sname)); 343 if (m == NULL) { 344 DPRINTF(("bootpcheck: m_pullup failed\n")); 345 return (-1); 346 } 347 } 348 bootp = mtod(m, struct bootp*); 349 350 if (bootp->bp_op != BOOTREPLY) { 351 DPRINTF(("bootpcheck: op %d is not reply\n", bootp->bp_op)); 352 return (-1); 353 } 354 if (bootp->bp_hlen != bpc->halen) { 355 DPRINTF(("bootpcheck: hlen %d != %d\n", bootp->bp_hlen, 356 bpc->halen)); 357 return (-1); 358 } 359 if (memcmp(bootp->bp_chaddr, bpc->haddr, bpc->halen)) { 360 #ifdef DEBUG_NFS_BOOT_DHCP 361 char *bp_chaddr, *haddr; 362 363 bp_chaddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 364 haddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 365 366 DPRINTF(("bootpcheck: incorrect hwaddr %s != %s\n", 367 ether_snprintf(bp_chaddr, 3 * bpc->halen, 368 bootp->bp_chaddr), 369 ether_snprintf(haddr, 3 * bpc->halen, bpc->haddr))); 370 371 free(bp_chaddr, M_TEMP); 372 free(haddr, M_TEMP); 373 #endif 374 return (-1); 375 } 376 if (bootp->bp_xid != bpc->xid) { 377 DPRINTF(("bootpcheck: xid %d != %d\n", bootp->bp_xid, 378 bpc->xid)); 379 return (-1); 380 } 381 382 /* 383 * OK, it's worth to look deeper. 384 * We copy the mbuf into a flat buffer here because 385 * m_pullup() is a bit limited for this purpose 386 * (doesn't allocate a cluster if necessary). 387 */ 388 bpc->replylen = m->m_pkthdr.len; 389 m_copydata(m, 0, bpc->replylen, (void *)bpc->replybuf); 390 bootp = bpc->replybuf; 391 392 /* 393 * Check if the IP address we get looks correct. 394 * (DHCP servers can send junk to unknown clients.) 395 * XXX more checks might be needed 396 */ 397 if (bootp->bp_yiaddr.s_addr == INADDR_ANY || 398 bootp->bp_yiaddr.s_addr == INADDR_BROADCAST) { 399 printf("nfs_boot: wrong IP addr %s", 400 inet_ntoa(bootp->bp_yiaddr)); 401 goto warn; 402 } 403 404 /* 405 * Check the vendor data. 406 */ 407 if (memcmp(bootp->bp_vend, vm_rfc1048, 4)) { 408 printf("nfs_boot: reply missing options"); 409 goto warn; 410 } 411 p = &bootp->bp_vend[4]; 412 limit = ((u_char*)bootp) + bpc->replylen; 413 while (p < limit) { 414 tag = *p++; 415 if (tag == TAG_END) 416 break; 417 if (tag == TAG_PAD) 418 continue; 419 len = *p++; 420 if ((p + len) > limit) { 421 printf("nfs_boot: option %d too long", tag); 422 goto warn; 423 } 424 switch (tag) { 425 #ifdef NFS_BOOT_DHCP 426 case TAG_DHCP_MSGTYPE: 427 if (*p != bpc->expected_dhcpmsgtype) 428 return (-1); 429 bpc->dhcp_ok = 1; 430 break; 431 case TAG_SERVERID: 432 memcpy(&bpc->dhcp_serverip.s_addr, p, 433 sizeof(bpc->dhcp_serverip.s_addr)); 434 break; 435 #endif 436 default: 437 break; 438 } 439 p += len; 440 } 441 return (0); 442 443 warn: 444 printf(" (bad reply from %s)\n", inet_ntoa(bootp->bp_siaddr)); 445 return (-1); 446 } 447 448 static int 449 bootpc_call(struct nfs_diskless *nd, struct lwp *lwp, int *flags) 450 { 451 struct socket *so; 452 struct ifnet *ifp = nd->nd_ifp; 453 static u_int32_t xid = ~0xFF; 454 struct bootp *bootp; /* request */ 455 struct mbuf *m, *nam; 456 struct sockaddr_in *sin; 457 int error; 458 const u_char *haddr; 459 u_char hafmt, halen; 460 struct bootpcontext bpc; 461 #ifdef NFS_BOOT_DHCP 462 char vci[64]; 463 int vcilen; 464 #endif 465 466 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 467 if (error) { 468 printf("bootp: socreate, error=%d\n", error); 469 return (error); 470 } 471 472 /* 473 * Initialize to NULL anything that will hold an allocation, 474 * and free each at the end if not null. 475 */ 476 bpc.replybuf = NULL; 477 m = nam = NULL; 478 479 /* Record our H/W (Ethernet) address. */ 480 { const struct sockaddr_dl *sdl = ifp->if_sadl; 481 switch (sdl->sdl_type) { 482 case IFT_ISO88025: 483 hafmt = HTYPE_IEEE802; 484 break; 485 case IFT_ETHER: 486 case IFT_FDDI: 487 hafmt = HTYPE_ETHERNET; 488 break; 489 default: 490 printf("bootp: unsupported interface type %d\n", 491 sdl->sdl_type); 492 error = EINVAL; 493 goto out; 494 } 495 halen = sdl->sdl_alen; 496 haddr = (const unsigned char *)CLLADDR(sdl); 497 } 498 499 /* 500 * Skip the route table when sending on this socket. 501 * If this is not done, ip_output finds the loopback 502 * interface (why?) and then fails because broadcast 503 * is not supported on that interface... 504 */ 505 { int32_t opt; 506 507 opt = 1; 508 error = so_setsockopt(NULL, so, SOL_SOCKET, SO_DONTROUTE, &opt, 509 sizeof(opt)); 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; 530 531 opt = 7; 532 error = so_setsockopt(NULL, so, IPPROTO_IP, IP_MULTICAST_TTL, 533 &opt, sizeof(opt)); 534 } 535 if (error) { 536 DPRINTF(("bootpc_call: IP_MULTICAST_TTL failed %d\n", error)); 537 goto out; 538 } 539 540 /* Set the receive timeout for the socket. */ 541 if ((error = nfs_boot_setrecvtimo(so))) { 542 DPRINTF(("bootpc_call: SO_RCVTIMEO failed %d\n", error)); 543 goto out; 544 } 545 546 /* 547 * Bind the local endpoint to a bootp client port. 548 */ 549 if ((error = nfs_boot_sobind_ipport(so, IPPORT_BOOTPC, lwp))) { 550 DPRINTF(("bootpc_call: bind failed %d\n", error)); 551 goto out; 552 } 553 554 /* 555 * Setup socket address for the server. 556 */ 557 nam = m_get(M_WAIT, MT_SONAME); 558 sin = mtod(nam, struct sockaddr_in *); 559 sin->sin_len = nam->m_len = sizeof(*sin); 560 sin->sin_family = AF_INET; 561 sin->sin_addr.s_addr = INADDR_BROADCAST; 562 sin->sin_port = htons(IPPORT_BOOTPS); 563 564 /* 565 * Allocate buffer used for request 566 */ 567 m = m_gethdr(M_WAIT, MT_DATA); 568 m_clget(m, M_WAIT); 569 bootp = mtod(m, struct bootp*); 570 m->m_pkthdr.len = m->m_len = BOOTP_SIZE_MAX; 571 m->m_pkthdr.rcvif = NULL; 572 573 /* 574 * Build the BOOTP reqest message. 575 * Note: xid is host order! (opaque to server) 576 */ 577 memset((void *)bootp, 0, BOOTP_SIZE_MAX); 578 bootp->bp_op = BOOTREQUEST; 579 bootp->bp_htype = hafmt; 580 bootp->bp_hlen = halen; /* Hardware address length */ 581 bootp->bp_xid = ++xid; 582 memcpy(bootp->bp_chaddr, haddr, halen); 583 #ifdef NFS_BOOT_BOOTP_REQFILE 584 strncpy(bootp->bp_file, NFS_BOOT_BOOTP_REQFILE, sizeof(bootp->bp_file)); 585 #endif 586 /* Fill-in the vendor data. */ 587 memcpy(bootp->bp_vend, vm_rfc1048, 4); 588 #ifdef NFS_BOOT_DHCP 589 bootp->bp_vend[4] = TAG_DHCP_MSGTYPE; 590 bootp->bp_vend[5] = 1; 591 bootp->bp_vend[6] = DHCPDISCOVER; 592 /* 593 * Insert a NetBSD Vendor Class Identifier option. 594 */ 595 snprintf(vci, sizeof(vci), "%s:%s:kernel:%s", ostype, MACHINE, 596 osrelease); 597 vcilen = strlen(vci); 598 bootp->bp_vend[7] = TAG_CLASSID; 599 bootp->bp_vend[8] = vcilen; 600 memcpy(&bootp->bp_vend[9], vci, vcilen); 601 bootp->bp_vend[9 + vcilen] = TAG_END; 602 #else 603 bootp->bp_vend[4] = TAG_END; 604 #endif 605 606 bpc.xid = xid; 607 bpc.haddr = haddr; 608 bpc.halen = halen; 609 bpc.replybuf = malloc(BOOTP_SIZE_MAX, M_DEVBUF, M_WAITOK); 610 if (bpc.replybuf == NULL) 611 panic("nfs_boot: malloc reply buf"); 612 #ifdef NFS_BOOT_DHCP 613 bpc.expected_dhcpmsgtype = DHCPOFFER; 614 bpc.dhcp_ok = 0; 615 #endif 616 617 error = nfs_boot_sendrecv(so, nam, bootpset, m, 618 bootpcheck, 0, 0, &bpc, lwp); 619 if (error) 620 goto out; 621 622 #ifdef NFS_BOOT_DHCP 623 if (bpc.dhcp_ok) { 624 u_int32_t leasetime; 625 bootp->bp_vend[6] = DHCPREQUEST; 626 bootp->bp_vend[7] = TAG_REQ_ADDR; 627 bootp->bp_vend[8] = 4; 628 memcpy(&bootp->bp_vend[9], &bpc.replybuf->bp_yiaddr, 4); 629 bootp->bp_vend[13] = TAG_SERVERID; 630 bootp->bp_vend[14] = 4; 631 memcpy(&bootp->bp_vend[15], &bpc.dhcp_serverip.s_addr, 4); 632 bootp->bp_vend[19] = TAG_LEASETIME; 633 bootp->bp_vend[20] = 4; 634 leasetime = htonl(300); 635 memcpy(&bootp->bp_vend[21], &leasetime, 4); 636 bootp->bp_vend[25] = TAG_CLASSID; 637 bootp->bp_vend[26] = vcilen; 638 memcpy(&bootp->bp_vend[27], vci, vcilen); 639 bootp->bp_vend[27 + vcilen] = TAG_END; 640 641 bpc.expected_dhcpmsgtype = DHCPACK; 642 643 error = nfs_boot_sendrecv(so, nam, bootpset, m, 644 bootpcheck, 0, 0, &bpc, lwp); 645 if (error) 646 goto out; 647 } 648 #endif 649 650 /* 651 * bootpcheck() has copied the receive mbuf into 652 * the buffer at bpc.replybuf. 653 */ 654 #ifdef NFS_BOOT_DHCP 655 printf("nfs_boot: %s next-server: %s\n", 656 (bpc.dhcp_ok ? "DHCP" : "BOOTP"), 657 #else 658 printf("nfs_boot: BOOTP next-server: %s\n", 659 #endif 660 inet_ntoa(bpc.replybuf->bp_siaddr)); 661 662 bootp_extract(bpc.replybuf, bpc.replylen, nd, flags); 663 664 out: 665 if (bpc.replybuf) 666 free(bpc.replybuf, M_DEVBUF); 667 if (m) 668 m_freem(m); 669 if (nam) 670 m_freem(nam); 671 soclose(so); 672 return (error); 673 } 674 675 static void 676 bootp_extract(struct bootp *bootp, int replylen, 677 struct nfs_diskless *nd, int *flags) 678 { 679 struct sockaddr_in *sin; 680 struct in_addr netmask; 681 struct in_addr gateway; 682 struct in_addr rootserver; 683 char *myname; /* my hostname */ 684 char *mydomain; /* my domainname */ 685 char *rootpath; 686 int mynamelen; 687 int mydomainlen; 688 int rootpathlen; 689 int overloaded; 690 u_int tag, len; 691 u_char *p, *limit; 692 693 /* Default these to "unspecified". */ 694 netmask.s_addr = 0; 695 gateway.s_addr = 0; 696 mydomain = myname = rootpath = NULL; 697 mydomainlen = mynamelen = rootpathlen = 0; 698 699 /* default root server to bootp next-server */ 700 rootserver = bootp->bp_siaddr; 701 /* assume that server name field is not overloaded by default */ 702 overloaded = 0; 703 704 p = &bootp->bp_vend[4]; 705 limit = ((u_char*)bootp) + replylen; 706 while (p < limit) { 707 tag = *p++; 708 if (tag == TAG_END) 709 break; 710 if (tag == TAG_PAD) 711 continue; 712 len = *p++; 713 #if 0 /* already done in bootpcheck() */ 714 if ((p + len) > limit) { 715 printf("nfs_boot: option %d too long\n", tag); 716 break; 717 } 718 #endif 719 switch (tag) { 720 case TAG_SUBNET_MASK: 721 memcpy(&netmask, p, 4); 722 break; 723 case TAG_GATEWAY: 724 /* Routers */ 725 memcpy(&gateway, p, 4); 726 break; 727 case TAG_HOST_NAME: 728 if (len >= sizeof(hostname)) { 729 printf("nfs_boot: host name >= %lu bytes", 730 (u_long)sizeof(hostname)); 731 break; 732 } 733 myname = p; 734 mynamelen = len; 735 break; 736 case TAG_DOMAIN_NAME: 737 if (len >= sizeof(domainname)) { 738 printf("nfs_boot: domain name >= %lu bytes", 739 (u_long)sizeof(domainname)); 740 break; 741 } 742 mydomain = p; 743 mydomainlen = len; 744 break; 745 case TAG_ROOT_PATH: 746 /* Leave some room for the server name. */ 747 if (len >= (MNAMELEN-10)) { 748 printf("nfs_boot: rootpath >=%d bytes", 749 (MNAMELEN-10)); 750 break; 751 } 752 rootpath = p; 753 rootpathlen = len; 754 break; 755 case TAG_SWAP_SERVER: 756 /* override NFS server address */ 757 memcpy(&rootserver, p, 4); 758 break; 759 #ifdef NFS_BOOT_DHCP 760 case TAG_OVERLOAD: 761 if (len > 0 && ((*p & 0x02) != 0)) 762 /* 763 * The server name field in the dhcp packet 764 * is overloaded and we can't find server 765 * name there. 766 */ 767 overloaded = 1; 768 break; 769 #endif 770 default: 771 break; 772 } 773 p += len; 774 } 775 776 /* 777 * Store and print network config info. 778 */ 779 if (myname) { 780 myname[mynamelen] = '\0'; 781 strncpy(hostname, myname, sizeof(hostname)); 782 hostnamelen = mynamelen; 783 printf("nfs_boot: my_name=%s\n", hostname); 784 } 785 if (mydomain) { 786 mydomain[mydomainlen] = '\0'; 787 strncpy(domainname, mydomain, sizeof(domainname)); 788 domainnamelen = mydomainlen; 789 printf("nfs_boot: my_domain=%s\n", domainname); 790 } 791 if (!(*flags & NFS_BOOT_HAS_MYIP)) { 792 nd->nd_myip = bootp->bp_yiaddr; 793 printf("nfs_boot: my_addr=%s\n", inet_ntoa(nd->nd_myip)); 794 *flags |= NFS_BOOT_HAS_MYIP; 795 } 796 if (!(*flags & NFS_BOOT_HAS_MASK)) { 797 nd->nd_mask = netmask; 798 printf("nfs_boot: my_mask=%s\n", inet_ntoa(nd->nd_mask)); 799 *flags |= NFS_BOOT_HAS_MASK; 800 } 801 if (!(*flags & NFS_BOOT_HAS_GWIP)) { 802 nd->nd_gwip = gateway; 803 printf("nfs_boot: gateway=%s\n", inet_ntoa(nd->nd_gwip)); 804 *flags |= NFS_BOOT_HAS_GWIP; 805 } 806 807 /* 808 * Store the information about our NFS root mount. 809 * The caller will print it, so be silent here. 810 */ 811 do { 812 struct nfs_dlmount *ndm = &nd->nd_root; 813 814 815 if (!(*flags & NFS_BOOT_HAS_SERVADDR)) { 816 /* Server IP address. */ 817 sin = (struct sockaddr_in *) &ndm->ndm_saddr; 818 memset((void *)sin, 0, sizeof(*sin)); 819 sin->sin_len = sizeof(*sin); 820 sin->sin_family = AF_INET; 821 sin->sin_addr = rootserver; 822 *flags |= NFS_BOOT_HAS_SERVADDR; 823 } 824 825 if (!(*flags & NFS_BOOT_HAS_SERVER)) { 826 /* Server name. */ 827 if (!overloaded && bootp->bp_sname[0] != 0 && 828 !memcmp(&rootserver, &bootp->bp_siaddr, 829 sizeof(struct in_addr))) 830 { 831 /* standard root server, we have the name */ 832 strncpy(ndm->ndm_host, bootp->bp_sname, 833 BP_SNAME_LEN-1); 834 *flags |= NFS_BOOT_HAS_SERVER; 835 } else { 836 /* Show the server IP address numerically. */ 837 strncpy(ndm->ndm_host, inet_ntoa(rootserver), 838 BP_SNAME_LEN-1); 839 *flags |= NFS_BOOT_HAS_SERVER; 840 } 841 } 842 843 if (!(*flags & NFS_BOOT_HAS_ROOTPATH)) { 844 len = strlen(ndm->ndm_host); 845 if (rootpath && 846 len + 1 + rootpathlen + 1 <= sizeof(ndm->ndm_host)) 847 { 848 ndm->ndm_host[len++] = ':'; 849 strncpy(ndm->ndm_host + len, 850 rootpath, rootpathlen); 851 ndm->ndm_host[len + rootpathlen] = '\0'; 852 *flags |= NFS_BOOT_HAS_ROOTPATH; 853 } /* else: upper layer will handle error */ 854 } 855 } while(0); 856 857 #ifdef TFTPROOT 858 #if BP_FILE_LEN > MNAMELEN 859 #define BOOTFILELEN MNAMELEN 860 #else 861 #define BOOTFILELEN BP_FILE_LEN 862 #endif 863 strncpy(nd->nd_bootfile, bootp->bp_file, BOOTFILELEN); 864 nd->nd_bootfile[BOOTFILELEN - 1] = '\0'; 865 #undef BOOTFILELEN 866 #endif /* TFTPROOT */ 867 } 868