1 /* $NetBSD: nfs_bootdhcp.c,v 1.41 2008/07/20 02:06:37 uwe 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 1.41 2008/07/20 02:06:37 uwe Exp $"); 48 49 #include "opt_nfs_boot.h" 50 #include "opt_tftproot.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/kernel.h> 55 #include <sys/device.h> 56 #include <sys/ioctl.h> 57 #include <sys/proc.h> 58 #include <sys/mount.h> 59 #include <sys/mbuf.h> 60 #include <sys/reboot.h> 61 #include <sys/socket.h> 62 #include <sys/socketvar.h> 63 64 #include <net/if.h> 65 #include <net/if_types.h> 66 #include <net/if_arp.h> /* ARPHRD_ETHER, etc. */ 67 #include <net/if_dl.h> 68 #include <net/if_ether.h> 69 #include <net/route.h> 70 71 #include <netinet/in.h> 72 #include <netinet/if_inarp.h> 73 74 #include <nfs/rpcv2.h> 75 76 #include <nfs/nfsproto.h> 77 #include <nfs/nfs.h> 78 #include <nfs/nfsmount.h> 79 #include <nfs/nfsdiskless.h> 80 81 /* 82 * There are two implementations of NFS diskless boot. 83 * This implementation uses BOOTP (RFC951, RFC1048), and 84 * the other uses Sun RPC/bootparams (nfs_bootparam.c). 85 * 86 * This method gets everything it needs with one BOOTP 87 * request and reply. Note that this actually uses only 88 * the old BOOTP functionality subset of DHCP. It is not 89 * clear that DHCP provides any advantage over BOOTP for 90 * diskless boot. DHCP allows the server to assign an IP 91 * address without any a-priori knowledge of the client, 92 * but we require that the server has a-priori knowledge 93 * of the client so it can export our (unique) NFS root. 94 * Given that the server needs a-priori knowledge about 95 * the client anyway, it might as well assign a fixed IP 96 * address for the client and support BOOTP. 97 * 98 * On the other hand, disk-FULL clients may use DHCP, but 99 * in that case the DHCP client should be user-mode code, 100 * and has no bearing on the code below. -gwr 101 */ 102 103 /* Begin stuff from bootp.h */ 104 /* Definitions from RFC951 */ 105 #define BP_CHADDR_LEN 16 106 #define BP_SNAME_LEN 64 107 #define BP_FILE_LEN 128 108 #define BP_VEND_LEN 64 109 struct bootp { 110 u_int8_t bp_op; /* packet opcode type */ 111 u_int8_t bp_htype; /* hardware addr type */ 112 u_int8_t bp_hlen; /* hardware addr length */ 113 u_int8_t bp_hops; /* gateway hops */ 114 u_int32_t bp_xid; /* transaction ID */ 115 u_int16_t bp_secs; /* seconds since boot began */ 116 u_int16_t bp_flags; /* RFC1532 broadcast, etc. */ 117 struct in_addr bp_ciaddr; /* client IP address */ 118 struct in_addr bp_yiaddr; /* 'your' IP address */ 119 struct in_addr bp_siaddr; /* server IP address */ 120 struct in_addr bp_giaddr; /* gateway IP address */ 121 u_int8_t bp_chaddr[BP_CHADDR_LEN]; /* client hardware address */ 122 char bp_sname[BP_SNAME_LEN]; /* server host name */ 123 char bp_file[BP_FILE_LEN]; /* boot file name */ 124 u_int8_t bp_vend[BP_VEND_LEN]; /* RFC1048 options */ 125 /* 126 * Note that BOOTP packets are allowed to be longer 127 * (see RFC 1532 sect. 2.1) and common practice is to 128 * allow the option data in bp_vend to extend into the 129 * additional space provided in longer packets. 130 */ 131 }; 132 133 #define IPPORT_BOOTPS 67 134 #define IPPORT_BOOTPC 68 135 136 #define BOOTREQUEST 1 137 #define BOOTREPLY 2 138 139 /* 140 * Is this available from the sockaddr_dl somehow? 141 * Perhaps (struct arphdr)->ar_hrd = ARPHRD_ETHER? 142 * The interface has ->if_type but not the ARP fmt. 143 */ 144 #define HTYPE_ETHERNET 1 145 #define HTYPE_IEEE802 6 146 147 /* 148 * Vendor magic cookie (v_magic) for RFC1048 149 */ 150 static const u_int8_t vm_rfc1048[4] = { 99, 130, 83, 99 }; 151 152 /* 153 * Tag values used to specify what information is being supplied in 154 * the vendor (options) data area of the packet. 155 */ 156 /* RFC 1048 */ 157 #define TAG_END ((unsigned char) 255) 158 #define TAG_PAD ((unsigned char) 0) 159 #define TAG_SUBNET_MASK ((unsigned char) 1) 160 #define TAG_TIME_OFFSET ((unsigned char) 2) 161 #define TAG_GATEWAY ((unsigned char) 3) 162 #define TAG_TIME_SERVER ((unsigned char) 4) 163 #define TAG_NAME_SERVER ((unsigned char) 5) 164 #define TAG_DOMAIN_SERVER ((unsigned char) 6) 165 #define TAG_LOG_SERVER ((unsigned char) 7) 166 #define TAG_COOKIE_SERVER ((unsigned char) 8) 167 #define TAG_LPR_SERVER ((unsigned char) 9) 168 #define TAG_IMPRESS_SERVER ((unsigned char) 10) 169 #define TAG_RLP_SERVER ((unsigned char) 11) 170 #define TAG_HOST_NAME ((unsigned char) 12) 171 #define TAG_BOOT_SIZE ((unsigned char) 13) 172 /* RFC 1395 */ 173 #define TAG_DUMP_FILE ((unsigned char) 14) 174 #define TAG_DOMAIN_NAME ((unsigned char) 15) 175 #define TAG_SWAP_SERVER ((unsigned char) 16) 176 #define TAG_ROOT_PATH ((unsigned char) 17) 177 /* End of stuff from bootp.h */ 178 179 #ifdef NFS_BOOT_DHCP 180 #define TAG_REQ_ADDR ((unsigned char) 50) 181 #define TAG_LEASETIME ((unsigned char) 51) 182 #define TAG_OVERLOAD ((unsigned char) 52) 183 #define TAG_DHCP_MSGTYPE ((unsigned char) 53) 184 #define TAG_SERVERID ((unsigned char) 54) 185 #define TAG_PARAM_REQ ((unsigned char) 55) 186 #define TAG_MSG ((unsigned char) 56) 187 #define TAG_MAXSIZE ((unsigned char) 57) 188 #define TAG_T1 ((unsigned char) 58) 189 #define TAG_T2 ((unsigned char) 59) 190 #define TAG_CLASSID ((unsigned char) 60) 191 #define TAG_CLIENTID ((unsigned char) 61) 192 #endif 193 194 #ifdef NFS_BOOT_DHCP 195 #define DHCPDISCOVER 1 196 #define DHCPOFFER 2 197 #define DHCPREQUEST 3 198 #define DHCPDECLINE 4 199 #define DHCPACK 5 200 #define DHCPNAK 6 201 #define DHCPRELEASE 7 202 #endif 203 204 #ifdef NFS_BOOT_DHCP 205 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+312-64) 206 #else 207 /* 208 * The "extended" size is somewhat arbitrary, but is 209 * constrained by the maximum message size specified 210 * by RFC1533 (567 total). This value increases the 211 * space for options from 64 bytes to 256 bytes. 212 */ 213 #define BOOTP_SIZE_MAX (sizeof(struct bootp)+256-64) 214 #endif 215 #define BOOTP_SIZE_MIN (sizeof(struct bootp)) 216 217 /* Convenience macro */ 218 #define INTOHL(ina) ((u_int32_t)ntohl((ina).s_addr)) 219 220 static int bootpc_call __P((struct nfs_diskless *, struct lwp *)); 221 static void bootp_extract __P((struct bootp *, int, struct nfs_diskless *)); 222 223 #ifdef DEBUG_NFS_BOOT_DHCP 224 #define DPRINTF(s) printf s 225 #else 226 #define DPRINTF(s) 227 #endif 228 229 230 /* 231 * Get our boot parameters using BOOTP. 232 */ 233 int 234 nfs_bootdhcp(nd, lwp) 235 struct nfs_diskless *nd; 236 struct lwp *lwp; 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, INADDR_ANY, INADDR_ANY, 246 INADDR_BROADCAST); 247 if (error) { 248 printf("nfs_boot: set ifaddr zero, error=%d\n", error); 249 return (error); 250 } 251 252 /* This function call does the real send/recv work. */ 253 error = bootpc_call(nd, lwp); 254 255 /* Get rid of the temporary (zero) IP address. */ 256 (void) nfs_boot_deladdress(ifp, lwp, INADDR_ANY); 257 258 /* NOW we can test the error from bootpc_call. */ 259 if (error) 260 goto out; 261 262 /* 263 * Do ifconfig with our real IP address and mask. 264 */ 265 error = nfs_boot_setaddress(ifp, lwp, nd->nd_myip.s_addr, 266 nd->nd_mask.s_addr, INADDR_ANY); 267 if (error) { 268 printf("nfs_boot: set ifaddr real, error=%d\n", error); 269 goto out; 270 } 271 272 out: 273 if (error) { 274 (void) nfs_boot_ifupdown(ifp, lwp, 0); 275 nfs_boot_flushrt(ifp); 276 } 277 return (error); 278 } 279 280 struct bootpcontext { 281 int xid; 282 const u_char *haddr; 283 u_char halen; 284 struct bootp *replybuf; 285 int replylen; 286 #ifdef NFS_BOOT_DHCP 287 char expected_dhcpmsgtype, dhcp_ok; 288 struct in_addr dhcp_serverip; 289 #endif 290 }; 291 292 static int bootpset __P((struct mbuf*, void*, int)); 293 static int bootpcheck __P((struct mbuf*, void*)); 294 295 static int 296 bootpset(struct mbuf *m, void *context, int waited) 297 { 298 struct bootp *bootp; 299 300 /* we know it's contigous (in 1 mbuf cluster) */ 301 bootp = mtod(m, struct bootp*); 302 303 bootp->bp_secs = htons(waited); 304 305 return (0); 306 } 307 308 static int 309 bootpcheck(m, context) 310 struct mbuf *m; 311 void *context; 312 { 313 struct bootp *bootp; 314 struct bootpcontext *bpc = context; 315 u_int tag, len; 316 u_char *p, *limit; 317 318 /* 319 * Is this a valid reply? 320 */ 321 if (m->m_pkthdr.len < BOOTP_SIZE_MIN) { 322 DPRINTF(("bootpcheck: short packet %d < %d\n", m->m_pkthdr.len, 323 BOOTP_SIZE_MIN)); 324 return (-1); 325 } 326 if (m->m_pkthdr.len > BOOTP_SIZE_MAX) { 327 DPRINTF(("Bootpcheck: long packet %d > %d\n", m->m_pkthdr.len, 328 BOOTP_SIZE_MAX)); 329 return (-1); 330 } 331 332 /* 333 * don't make first checks more expensive than necessary 334 */ 335 if (m->m_len < offsetof(struct bootp, bp_sname)) { 336 m = m_pullup(m, offsetof(struct bootp, bp_sname)); 337 if (m == NULL) { 338 DPRINTF(("bootpcheck: m_pullup failed\n")); 339 return (-1); 340 } 341 } 342 bootp = mtod(m, struct bootp*); 343 344 if (bootp->bp_op != BOOTREPLY) { 345 DPRINTF(("bootpcheck: op %d is not reply\n", bootp->bp_op)); 346 return (-1); 347 } 348 if (bootp->bp_hlen != bpc->halen) { 349 DPRINTF(("bootpcheck: hlen %d != %d\n", bootp->bp_hlen, 350 bpc->halen)); 351 return (-1); 352 } 353 if (memcmp(bootp->bp_chaddr, bpc->haddr, bpc->halen)) { 354 #ifdef DEBUG_NFS_BOOT_DHCP 355 char *bp_chaddr, *haddr; 356 357 bp_chaddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 358 haddr = malloc(3 * bpc->halen, M_TEMP, M_WAITOK); 359 360 DPRINTF(("bootpcheck: incorrect hwaddr %s != %s\n", 361 ether_snprintf(bp_chaddr, 3 * bpc->halen, 362 bootp->bp_chaddr), 363 ether_snprintf(haddr, 3 * bpc->halen, bpc->haddr))); 364 365 free(bp_chaddr, M_TEMP); 366 free(haddr, M_TEMP); 367 #endif 368 return (-1); 369 } 370 if (bootp->bp_xid != bpc->xid) { 371 DPRINTF(("bootpcheck: xid %d != %d\n", bootp->bp_xid, 372 bpc->xid)); 373 return (-1); 374 } 375 376 /* 377 * OK, it's worth to look deeper. 378 * We copy the mbuf into a flat buffer here because 379 * m_pullup() is a bit limited for this purpose 380 * (doesn't allocate a cluster if necessary). 381 */ 382 bpc->replylen = m->m_pkthdr.len; 383 m_copydata(m, 0, bpc->replylen, (void *)bpc->replybuf); 384 bootp = bpc->replybuf; 385 386 /* 387 * Check if the IP address we get looks correct. 388 * (DHCP servers can send junk to unknown clients.) 389 * XXX more checks might be needed 390 */ 391 if (bootp->bp_yiaddr.s_addr == INADDR_ANY || 392 bootp->bp_yiaddr.s_addr == INADDR_BROADCAST) { 393 printf("nfs_boot: wrong IP addr %s", 394 inet_ntoa(bootp->bp_yiaddr)); 395 goto warn; 396 } 397 398 /* 399 * Check the vendor data. 400 */ 401 if (memcmp(bootp->bp_vend, vm_rfc1048, 4)) { 402 printf("nfs_boot: reply missing options"); 403 goto warn; 404 } 405 p = &bootp->bp_vend[4]; 406 limit = ((u_char*)bootp) + bpc->replylen; 407 while (p < limit) { 408 tag = *p++; 409 if (tag == TAG_END) 410 break; 411 if (tag == TAG_PAD) 412 continue; 413 len = *p++; 414 if ((p + len) > limit) { 415 printf("nfs_boot: option %d too long", tag); 416 goto warn; 417 } 418 switch (tag) { 419 #ifdef NFS_BOOT_DHCP 420 case TAG_DHCP_MSGTYPE: 421 if (*p != bpc->expected_dhcpmsgtype) 422 return (-1); 423 bpc->dhcp_ok = 1; 424 break; 425 case TAG_SERVERID: 426 memcpy(&bpc->dhcp_serverip.s_addr, p, 427 sizeof(bpc->dhcp_serverip.s_addr)); 428 break; 429 #endif 430 default: 431 break; 432 } 433 p += len; 434 } 435 return (0); 436 437 warn: 438 printf(" (bad reply from %s)\n", inet_ntoa(bootp->bp_siaddr)); 439 return (-1); 440 } 441 442 static int 443 bootpc_call(nd, lwp) 444 struct nfs_diskless *nd; 445 struct lwp *lwp; 446 { 447 struct socket *so; 448 struct ifnet *ifp = nd->nd_ifp; 449 static u_int32_t xid = ~0xFF; 450 struct bootp *bootp; /* request */ 451 struct mbuf *m, *nam; 452 struct sockaddr_in *sin; 453 int error; 454 const u_char *haddr; 455 u_char hafmt, halen; 456 struct bootpcontext bpc; 457 #ifdef NFS_BOOT_DHCP 458 char vci[64]; 459 int vcilen; 460 #endif 461 462 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 463 if (error) { 464 printf("bootp: socreate, error=%d\n", error); 465 return (error); 466 } 467 468 /* 469 * Initialize to NULL anything that will hold an allocation, 470 * and free each at the end if not null. 471 */ 472 bpc.replybuf = NULL; 473 m = nam = NULL; 474 475 /* Record our H/W (Ethernet) address. */ 476 { const struct sockaddr_dl *sdl = ifp->if_sadl; 477 switch (sdl->sdl_type) { 478 case IFT_ISO88025: 479 hafmt = HTYPE_IEEE802; 480 break; 481 case IFT_ETHER: 482 case IFT_FDDI: 483 hafmt = HTYPE_ETHERNET; 484 break; 485 default: 486 printf("bootp: unsupported interface type %d\n", 487 sdl->sdl_type); 488 error = EINVAL; 489 goto out; 490 } 491 halen = sdl->sdl_alen; 492 haddr = (const unsigned char *)CLLADDR(sdl); 493 } 494 495 /* 496 * Skip the route table when sending on this socket. 497 * If this is not done, ip_output finds the loopback 498 * interface (why?) and then fails because broadcast 499 * is not supported on that interface... 500 */ 501 { int32_t *opt; 502 m = m_get(M_WAIT, MT_SOOPTS); 503 opt = mtod(m, int32_t *); 504 m->m_len = sizeof(*opt); 505 *opt = 1; 506 error = sosetopt(so, SOL_SOCKET, SO_DONTROUTE, m); 507 m = NULL; /* was consumed */ 508 } 509 if (error) { 510 DPRINTF(("bootpc_call: SO_DONTROUTE failed %d\n", error)); 511 goto out; 512 } 513 514 /* Enable broadcast. */ 515 if ((error = nfs_boot_enbroadcast(so))) { 516 DPRINTF(("bootpc_call: SO_BROADCAST failed %d\n", error)); 517 goto out; 518 } 519 520 /* 521 * Set some TTL so we can boot through routers. 522 * Real BOOTP forwarding agents don't need this; they obey "bp_hops" 523 * and set "bp_giaddr", thus rewrite the packet anyway. 524 * The "helper-address" feature of some popular router vendor seems 525 * to do simple IP forwarding and drops packets with (ip_ttl == 1). 526 */ 527 { u_char *opt; 528 m = m_get(M_WAIT, MT_SOOPTS); 529 opt = mtod(m, u_char *); 530 m->m_len = sizeof(*opt); 531 *opt = 7; 532 error = sosetopt(so, IPPROTO_IP, IP_MULTICAST_TTL, m); 533 m = NULL; /* was consumed */ 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); 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(bootp, replylen, nd) 677 struct bootp *bootp; 678 int replylen; 679 struct nfs_diskless *nd; 680 { 681 struct sockaddr_in *sin; 682 struct in_addr netmask; 683 struct in_addr gateway; 684 struct in_addr rootserver; 685 char *myname; /* my hostname */ 686 char *mydomain; /* my domainname */ 687 char *rootpath; 688 int mynamelen; 689 int mydomainlen; 690 int rootpathlen; 691 int overloaded; 692 u_int tag, len; 693 u_char *p, *limit; 694 695 /* Default these to "unspecified". */ 696 netmask.s_addr = 0; 697 gateway.s_addr = 0; 698 mydomain = myname = rootpath = NULL; 699 mydomainlen = mynamelen = rootpathlen = 0; 700 701 /* default root server to bootp next-server */ 702 rootserver = bootp->bp_siaddr; 703 /* assume that server name field is not overloaded by default */ 704 overloaded = 0; 705 706 p = &bootp->bp_vend[4]; 707 limit = ((u_char*)bootp) + replylen; 708 while (p < limit) { 709 tag = *p++; 710 if (tag == TAG_END) 711 break; 712 if (tag == TAG_PAD) 713 continue; 714 len = *p++; 715 #if 0 /* already done in bootpcheck() */ 716 if ((p + len) > limit) { 717 printf("nfs_boot: option %d too long\n", tag); 718 break; 719 } 720 #endif 721 switch (tag) { 722 case TAG_SUBNET_MASK: 723 memcpy(&netmask, p, 4); 724 break; 725 case TAG_GATEWAY: 726 /* Routers */ 727 memcpy(&gateway, p, 4); 728 break; 729 case TAG_HOST_NAME: 730 if (len >= sizeof(hostname)) { 731 printf("nfs_boot: host name >= %lu bytes", 732 (u_long)sizeof(hostname)); 733 break; 734 } 735 myname = p; 736 mynamelen = len; 737 break; 738 case TAG_DOMAIN_NAME: 739 if (len >= sizeof(domainname)) { 740 printf("nfs_boot: domain name >= %lu bytes", 741 (u_long)sizeof(domainname)); 742 break; 743 } 744 mydomain = p; 745 mydomainlen = len; 746 break; 747 case TAG_ROOT_PATH: 748 /* Leave some room for the server name. */ 749 if (len >= (MNAMELEN-10)) { 750 printf("nfs_boot: rootpath >=%d bytes", 751 (MNAMELEN-10)); 752 break; 753 } 754 rootpath = p; 755 rootpathlen = len; 756 break; 757 case TAG_SWAP_SERVER: 758 /* override NFS server address */ 759 memcpy(&rootserver, p, 4); 760 break; 761 #ifdef NFS_BOOT_DHCP 762 case TAG_OVERLOAD: 763 if (len > 0 && ((*p & 0x02) != 0)) 764 /* 765 * The server name field in the dhcp packet 766 * is overloaded and we can't find server 767 * name there. 768 */ 769 overloaded = 1; 770 break; 771 #endif 772 default: 773 break; 774 } 775 p += len; 776 } 777 778 /* 779 * Store and print network config info. 780 */ 781 if (myname) { 782 myname[mynamelen] = '\0'; 783 strncpy(hostname, myname, sizeof(hostname)); 784 hostnamelen = mynamelen; 785 printf("nfs_boot: my_name=%s\n", hostname); 786 } 787 if (mydomain) { 788 mydomain[mydomainlen] = '\0'; 789 strncpy(domainname, mydomain, sizeof(domainname)); 790 domainnamelen = mydomainlen; 791 printf("nfs_boot: my_domain=%s\n", domainname); 792 } 793 nd->nd_myip = bootp->bp_yiaddr; 794 if (nd->nd_myip.s_addr) 795 printf("nfs_boot: my_addr=%s\n", inet_ntoa(nd->nd_myip)); 796 nd->nd_mask = netmask; 797 if (nd->nd_mask.s_addr) 798 printf("nfs_boot: my_mask=%s\n", inet_ntoa(nd->nd_mask)); 799 nd->nd_gwip = gateway; 800 if (nd->nd_gwip.s_addr) 801 printf("nfs_boot: gateway=%s\n", inet_ntoa(nd->nd_gwip)); 802 803 /* 804 * Store the information about our NFS root mount. 805 * The caller will print it, so be silent here. 806 */ 807 { 808 struct nfs_dlmount *ndm = &nd->nd_root; 809 810 /* Server IP address. */ 811 sin = (struct sockaddr_in *) &ndm->ndm_saddr; 812 memset((void *)sin, 0, sizeof(*sin)); 813 sin->sin_len = sizeof(*sin); 814 sin->sin_family = AF_INET; 815 sin->sin_addr = rootserver; 816 /* Server name. */ 817 if (!overloaded && bootp->bp_sname[0] != 0 && 818 !memcmp(&rootserver, &bootp->bp_siaddr, 819 sizeof(struct in_addr))) { 820 /* standard root server, we have the name */ 821 strncpy(ndm->ndm_host, bootp->bp_sname, BP_SNAME_LEN-1); 822 } else { 823 /* Show the server IP address numerically. */ 824 strncpy(ndm->ndm_host, inet_ntoa(rootserver), 825 BP_SNAME_LEN-1); 826 } 827 len = strlen(ndm->ndm_host); 828 if (rootpath && 829 len + 1 + rootpathlen + 1 <= sizeof(ndm->ndm_host)) { 830 ndm->ndm_host[len++] = ':'; 831 strncpy(ndm->ndm_host + len, 832 rootpath, rootpathlen); 833 ndm->ndm_host[len + rootpathlen] = '\0'; 834 } /* else: upper layer will handle error */ 835 } 836 837 #ifdef TFTPROOT 838 #if BP_FILE_LEN > MNAMELEN 839 #define BOOTFILELEN MNAMELEN 840 #else 841 #define BOOTFILELEN BP_FILE_LEN 842 #endif 843 strncpy(nd->nd_bootfile, bootp->bp_file, BOOTFILELEN); 844 nd->nd_bootfile[BOOTFILELEN - 1] = '\0'; 845 #undef BOOTFILELEN 846 #endif /* TFTPROOT */ 847 } 848