1 /* $NetBSD: nfs_boot.c,v 1.87 2016/11/15 01:50:06 ozaki-r 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, specifically getting information 34 * about where to mount root from, what pathnames, etc. 35 */ 36 37 #include <sys/cdefs.h> 38 __KERNEL_RCSID(0, "$NetBSD: nfs_boot.c,v 1.87 2016/11/15 01:50:06 ozaki-r Exp $"); 39 40 #ifdef _KERNEL_OPT 41 #include "opt_nfs.h" 42 #include "opt_tftproot.h" 43 #include "opt_nfs_boot.h" 44 #endif 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/kernel.h> 49 #include <sys/device.h> 50 #include <sys/ioctl.h> 51 #include <sys/proc.h> 52 #include <sys/mount.h> 53 #include <sys/mbuf.h> 54 #include <sys/reboot.h> 55 #include <sys/socket.h> 56 #include <sys/socketvar.h> 57 58 #include <net/if.h> 59 #include <net/route.h> 60 #include <net/if_ether.h> 61 #include <net/if_types.h> 62 63 #include <netinet/in.h> 64 #include <netinet/if_inarp.h> 65 66 #include <nfs/rpcv2.h> 67 #include <nfs/krpc.h> 68 #include <nfs/xdr_subs.h> 69 70 #include <nfs/nfsproto.h> 71 #include <nfs/nfs.h> 72 #include <nfs/nfsmount.h> 73 #include <nfs/nfsdiskless.h> 74 75 /* 76 * There are three implementations of NFS diskless boot. 77 * One implementation uses BOOTP (RFC951, RFC1048), 78 * Sun RPC/bootparams or static configuration. See the 79 * files: 80 * nfs_bootdhcp.c: BOOTP (RFC951, RFC1048) 81 * nfs_bootparam.c: Sun RPC/bootparams 82 * nfs_bootstatic.c: honour config(1) description 83 */ 84 #if defined(NFS_BOOT_BOOTP) || defined(NFS_BOOT_DHCP) 85 int nfs_boot_rfc951 = 1; /* BOOTP enabled (default) */ 86 #endif 87 #ifdef NFS_BOOT_BOOTPARAM 88 int nfs_boot_bootparam = 1; /* BOOTPARAM enabled (default) */ 89 #endif 90 #ifdef NFS_BOOT_BOOTSTATIC 91 int nfs_boot_bootstatic = 1; /* BOOTSTATIC enabled (default) */ 92 #endif 93 94 #define IP_MIN_MTU 576 95 96 /* mountd RPC */ 97 static int md_mount(struct sockaddr_in *mdsin, char *path, 98 struct nfs_args *argp, struct lwp *l); 99 100 static int nfs_boot_delroute_matcher(struct rtentry *, void *); 101 static void nfs_boot_defrt(struct in_addr *); 102 static int nfs_boot_getfh(struct nfs_dlmount *ndm, struct lwp *); 103 104 105 /* 106 * Called with an empty nfs_diskless struct to be filled in. 107 * Find an interface, determine its ip address (etc.) and 108 * save all the boot parameters in the nfs_diskless struct. 109 */ 110 int 111 nfs_boot_init(struct nfs_diskless *nd, struct lwp *lwp) 112 { 113 struct ifnet *ifp; 114 int error = 0; 115 int flags __unused; 116 117 /* Explicitly necessary or build fails 118 * due to unused variable, otherwise. 119 */ 120 flags = 0; 121 122 /* 123 * Find the network interface. 124 */ 125 ifp = ifunit(device_xname(root_device)); 126 if (ifp == NULL) { 127 printf("nfs_boot: '%s' not found\n", 128 device_xname(root_device)); 129 return (ENXIO); 130 } 131 nd->nd_ifp = ifp; 132 133 error = EADDRNOTAVAIL; /* ??? */ 134 #if defined(NFS_BOOT_BOOTSTATIC) 135 if (error && nfs_boot_bootstatic) { 136 printf("nfs_boot: trying static\n"); 137 error = nfs_bootstatic(nd, lwp, &flags); 138 } 139 #endif 140 #if defined(NFS_BOOT_BOOTP) || defined(NFS_BOOT_DHCP) 141 if (error && nfs_boot_rfc951) { 142 #if defined(NFS_BOOT_DHCP) 143 printf("nfs_boot: trying DHCP/BOOTP\n"); 144 #else 145 printf("nfs_boot: trying BOOTP\n"); 146 #endif 147 error = nfs_bootdhcp(nd, lwp, &flags); 148 } 149 #endif 150 #ifdef NFS_BOOT_BOOTPARAM 151 if (error && nfs_boot_bootparam) { 152 printf("nfs_boot: trying RARP (and RPC/bootparam)\n"); 153 error = nfs_bootparam(nd, lwp, &flags); 154 } 155 #endif 156 if (error) 157 return (error); 158 159 /* 160 * Set MTU if passed 161 */ 162 if (nd->nd_mtu >= IP_MIN_MTU ) 163 nfs_boot_setmtu(nd->nd_ifp, nd->nd_mtu, lwp); 164 165 /* 166 * If the gateway address is set, add a default route. 167 * (The mountd RPCs may go across a gateway.) 168 */ 169 if (nd->nd_gwip.s_addr) 170 nfs_boot_defrt(&nd->nd_gwip); 171 172 #ifdef TFTPROOT 173 if (nd->nd_nomount) 174 goto out; 175 #endif 176 /* 177 * Now fetch the NFS file handles as appropriate. 178 */ 179 error = nfs_boot_getfh(&nd->nd_root, lwp); 180 181 if (error) 182 nfs_boot_cleanup(nd, lwp); 183 184 #ifdef TFTPROOT 185 out: 186 #endif 187 return (error); 188 } 189 190 void 191 nfs_boot_cleanup(struct nfs_diskless *nd, struct lwp *lwp) 192 { 193 194 nfs_boot_deladdress(nd->nd_ifp, lwp, nd->nd_myip.s_addr); 195 nfs_boot_ifupdown(nd->nd_ifp, lwp, 0); 196 nfs_boot_flushrt(nd->nd_ifp); 197 } 198 199 int 200 nfs_boot_ifupdown(struct ifnet *ifp, struct lwp *lwp, int up) 201 { 202 struct socket *so; 203 struct ifreq ireq; 204 int error; 205 206 memset(&ireq, 0, sizeof(ireq)); 207 memcpy(ireq.ifr_name, ifp->if_xname, IFNAMSIZ); 208 209 /* 210 * Get a socket to use for various things in here. 211 * After this, use "goto out" to cleanup and return. 212 */ 213 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 214 if (error) { 215 printf("ifupdown: socreate, error=%d\n", error); 216 return (error); 217 } 218 219 /* 220 * Bring up the interface. (just set the "up" flag) 221 * Get the old interface flags and or IFF_UP into them so 222 * things like media selection flags are not clobbered. 223 */ 224 error = ifioctl(so, SIOCGIFFLAGS, (void *)&ireq, lwp); 225 if (error) { 226 printf("ifupdown: GIFFLAGS, error=%d\n", error); 227 goto out; 228 } 229 if (up) 230 ireq.ifr_flags |= IFF_UP; 231 else 232 ireq.ifr_flags &= ~IFF_UP; 233 error = ifioctl(so, SIOCSIFFLAGS, &ireq, lwp); 234 if (error) { 235 printf("ifupdown: SIFFLAGS, error=%d\n", error); 236 goto out; 237 } 238 239 if (up) 240 /* give the link some time to get up */ 241 tsleep(nfs_boot_ifupdown, PZERO, "nfsbif", 3 * hz); 242 out: 243 soclose(so); 244 return (error); 245 } 246 247 void 248 nfs_boot_setmtu(struct ifnet *ifp, int mtu, struct lwp *lwp) 249 { 250 struct socket *so; 251 struct ifreq ireq; 252 int error; 253 254 memset(&ireq, 0, sizeof(ireq)); 255 memcpy(ireq.ifr_name, ifp->if_xname, IFNAMSIZ); 256 257 /* 258 * Get a socket to use for various things in here. 259 * After this, use "goto out" to cleanup and return. 260 */ 261 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 262 if (error) { 263 printf("setmtu: socreate, error=%d\n", error); 264 return; 265 } 266 267 /* 268 * Get structure, set the new MTU, push structure. 269 */ 270 error = ifioctl(so, SIOCGIFMTU, (void *)&ireq, lwp); 271 if (error) { 272 printf("setmtu: GIFMTU, error=%d\n", error); 273 goto out; 274 } 275 276 ireq.ifr_mtu = mtu; 277 278 error = ifioctl(so, SIOCSIFMTU, &ireq, lwp); 279 if (error) { 280 printf("setmtu: SIFMTU, error=%d\n", error); 281 goto out; 282 } 283 284 out: 285 soclose(so); 286 return; 287 } 288 289 int 290 nfs_boot_setaddress(struct ifnet *ifp, struct lwp *lwp, 291 uint32_t addr, uint32_t netmask, uint32_t braddr) 292 { 293 struct socket *so; 294 struct ifaliasreq iareq; 295 struct sockaddr_in *sin; 296 int error; 297 298 /* 299 * Get a socket to use for various things in here. 300 * After this, use "goto out" to cleanup and return. 301 */ 302 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 303 if (error) { 304 printf("setaddress: socreate, error=%d\n", error); 305 return (error); 306 } 307 308 memset(&iareq, 0, sizeof(iareq)); 309 memcpy(iareq.ifra_name, ifp->if_xname, IFNAMSIZ); 310 311 /* Set the I/F address */ 312 sin = (struct sockaddr_in *)&iareq.ifra_addr; 313 sin->sin_len = sizeof(*sin); 314 sin->sin_family = AF_INET; 315 sin->sin_addr.s_addr = addr; 316 317 /* Set the netmask */ 318 if (netmask != INADDR_ANY) { 319 sin = (struct sockaddr_in *)&iareq.ifra_mask; 320 sin->sin_len = sizeof(*sin); 321 sin->sin_family = AF_INET; 322 sin->sin_addr.s_addr = netmask; 323 } /* else leave subnetmask unspecified (len=0) */ 324 325 /* Set the broadcast addr. */ 326 if (braddr != INADDR_ANY) { 327 sin = (struct sockaddr_in *)&iareq.ifra_broadaddr; 328 sin->sin_len = sizeof(*sin); 329 sin->sin_family = AF_INET; 330 sin->sin_addr.s_addr = braddr; 331 } /* else leave broadcast addr unspecified (len=0) */ 332 333 error = ifioctl(so, SIOCAIFADDR, (void *)&iareq, lwp); 334 if (error) { 335 printf("setaddress, error=%d\n", error); 336 goto out; 337 } 338 339 /* give the link some time to get up */ 340 tsleep(nfs_boot_setaddress, PZERO, "nfsbtd", 3 * hz); 341 out: 342 soclose(so); 343 return (error); 344 } 345 346 int 347 nfs_boot_deladdress(struct ifnet *ifp, struct lwp *lwp, uint32_t addr) 348 { 349 struct socket *so; 350 struct ifreq ifr; 351 struct sockaddr_in sin; 352 struct in_addr ia = {.s_addr = addr}; 353 int error; 354 355 /* 356 * Get a socket to use for various things in here. 357 * After this, use "goto out" to cleanup and return. 358 */ 359 error = socreate(AF_INET, &so, SOCK_DGRAM, 0, lwp, NULL); 360 if (error) { 361 printf("deladdress: socreate, error=%d\n", error); 362 return (error); 363 } 364 365 memset(&ifr, 0, sizeof(ifr)); 366 memcpy(ifr.ifr_name, ifp->if_xname, IFNAMSIZ); 367 368 sockaddr_in_init(&sin, &ia, 0); 369 ifreq_setaddr(SIOCDIFADDR, &ifr, sintocsa(&sin)); 370 371 error = ifioctl(so, SIOCDIFADDR, &ifr, lwp); 372 if (error) { 373 printf("deladdress, error=%d\n", error); 374 goto out; 375 } 376 377 out: 378 soclose(so); 379 return (error); 380 } 381 382 int 383 nfs_boot_setrecvtimo(struct socket *so) 384 { 385 struct timeval tv; 386 387 tv.tv_sec = 1; 388 tv.tv_usec = 0; 389 390 return (so_setsockopt(NULL, so, SOL_SOCKET, SO_RCVTIMEO, &tv, 391 sizeof(tv))); 392 } 393 394 int 395 nfs_boot_enbroadcast(struct socket *so) 396 { 397 int32_t on; 398 399 on = 1; 400 return (so_setsockopt(NULL, so, SOL_SOCKET, SO_BROADCAST, &on, 401 sizeof(on))); 402 } 403 404 int 405 nfs_boot_sobind_ipport(struct socket *so, uint16_t port, struct lwp *l) 406 { 407 struct sockaddr_in sin; 408 int error; 409 410 sin.sin_len = sizeof(sin); 411 sin.sin_family = AF_INET; 412 sin.sin_addr.s_addr = INADDR_ANY; 413 sin.sin_port = htons(port); 414 error = sobind(so, (struct sockaddr *)&sin, l); 415 return (error); 416 } 417 418 /* 419 * What is the longest we will wait before re-sending a request? 420 * Note this is also the frequency of "timeout" messages. 421 * The re-send loop counts up linearly to this maximum, so the 422 * first complaint will happen after (1+2+3+4+5)=15 seconds. 423 */ 424 #define MAX_RESEND_DELAY 5 /* seconds */ 425 #define TOTAL_TIMEOUT 30 /* seconds */ 426 427 int 428 nfs_boot_sendrecv(struct socket *so, struct sockaddr_in *nam, 429 int (*sndproc)(struct mbuf *, void *, int), 430 struct mbuf *snd, 431 int (*rcvproc)(struct mbuf **, void *), 432 struct mbuf **rcv, struct mbuf **from_p, 433 void *context, struct lwp *lwp) 434 { 435 int error, rcvflg, timo, secs, waited; 436 struct mbuf *m, *from; 437 struct uio uio; 438 439 /* Free at end if not null. */ 440 from = NULL; 441 442 /* 443 * Send it, repeatedly, until a reply is received, 444 * but delay each re-send by an increasing amount. 445 * If the delay hits the maximum, start complaining. 446 */ 447 waited = timo = 0; 448 send_again: 449 waited += timo; 450 if (waited >= TOTAL_TIMEOUT) 451 return (ETIMEDOUT); 452 453 /* Determine new timeout. */ 454 if (timo < MAX_RESEND_DELAY) 455 timo++; 456 else 457 printf("nfs_boot: timeout...\n"); 458 459 if (sndproc) { 460 error = (*sndproc)(snd, context, waited); 461 if (error) 462 goto out; 463 } 464 465 /* Send request (or re-send). */ 466 m = m_copypacket(snd, M_WAIT); 467 if (m == NULL) { 468 error = ENOBUFS; 469 goto out; 470 } 471 error = (*so->so_send)(so, (struct sockaddr *)nam, NULL, 472 m, NULL, 0, lwp); 473 if (error) { 474 printf("nfs_boot: sosend: %d\n", error); 475 goto out; 476 } 477 m = NULL; 478 479 /* 480 * Wait for up to timo seconds for a reply. 481 * The socket receive timeout was set to 1 second. 482 */ 483 484 secs = timo; 485 for (;;) { 486 if (from) { 487 m_freem(from); 488 from = NULL; 489 } 490 if (m) { 491 m_freem(m); 492 m = NULL; 493 } 494 uio.uio_resid = 1 << 16; /* ??? */ 495 rcvflg = 0; 496 error = (*so->so_receive)(so, &from, &uio, &m, NULL, &rcvflg); 497 if (error == EWOULDBLOCK) { 498 if (--secs <= 0) 499 goto send_again; 500 continue; 501 } 502 if (error) 503 goto out; 504 #ifdef DIAGNOSTIC 505 if (!m || !(m->m_flags & M_PKTHDR) 506 || (1 << 16) - uio.uio_resid != m->m_pkthdr.len) 507 panic("nfs_boot_sendrecv: return size"); 508 #endif 509 510 if ((*rcvproc)(&m, context)) 511 continue; 512 513 if (rcv) 514 *rcv = m; 515 else 516 m_freem(m); 517 if (from_p) { 518 *from_p = from; 519 from = NULL; 520 } 521 break; 522 } 523 out: 524 if (from) m_freem(from); 525 return (error); 526 } 527 528 /* 529 * Install a default route to the passed IP address. 530 */ 531 static void 532 nfs_boot_defrt(struct in_addr *gw_ip) 533 { 534 struct sockaddr dst, gw, mask; 535 struct sockaddr_in *sin; 536 int error; 537 538 /* Destination: (default) */ 539 memset((void *)&dst, 0, sizeof(dst)); 540 dst.sa_len = sizeof(dst); 541 dst.sa_family = AF_INET; 542 /* Gateway: */ 543 memset((void *)&gw, 0, sizeof(gw)); 544 sin = (struct sockaddr_in *)&gw; 545 sin->sin_len = sizeof(*sin); 546 sin->sin_family = AF_INET; 547 sin->sin_addr.s_addr = gw_ip->s_addr; 548 /* Mask: (zero length) */ 549 /* XXX - Just pass a null pointer? */ 550 memset(&mask, 0, sizeof(mask)); 551 552 /* add, dest, gw, mask, flags, 0 */ 553 error = rtrequest(RTM_ADD, &dst, &gw, &mask, 554 (RTF_UP | RTF_GATEWAY | RTF_STATIC), NULL); 555 if (error) { 556 printf("nfs_boot: add route, error=%d\n", error); 557 error = 0; 558 } 559 } 560 561 static int 562 nfs_boot_delroute_matcher(struct rtentry *rt, void *w) 563 { 564 565 if ((void *)rt->rt_ifp != w) 566 return 0; 567 568 return 1; 569 } 570 571 void 572 nfs_boot_flushrt(struct ifnet *ifp) 573 { 574 575 rt_delete_matched_entries(AF_INET, nfs_boot_delroute_matcher, ifp); 576 } 577 578 /* 579 * Get an initial NFS file handle using Sun RPC/mountd. 580 * Separate function because we used to call it twice. 581 * (once for root and once for swap) 582 * 583 * ndm output 584 */ 585 static int 586 nfs_boot_getfh(struct nfs_dlmount *ndm, struct lwp *l) 587 { 588 struct nfs_args *args; 589 struct sockaddr_in *sin; 590 char *pathname; 591 int error; 592 u_int16_t port; 593 594 args = &ndm->ndm_args; 595 596 /* Initialize mount args. */ 597 memset((void *) args, 0, sizeof(*args)); 598 args->addr = &ndm->ndm_saddr; 599 args->addrlen = args->addr->sa_len; 600 #ifdef NFS_BOOT_TCP 601 args->sotype = SOCK_STREAM; 602 #else 603 args->sotype = SOCK_DGRAM; 604 #endif 605 args->fh = ndm->ndm_fh; 606 args->hostname = ndm->ndm_host; 607 args->flags = NFSMNT_NOCONN | NFSMNT_RESVPORT; 608 609 #ifndef NFS_V2_ONLY 610 args->flags |= NFSMNT_NFSV3; 611 #endif 612 #ifdef NFS_BOOT_OPTIONS 613 args->flags |= NFS_BOOT_OPTIONS; 614 #endif 615 #ifdef NFS_BOOT_RWSIZE 616 /* 617 * Reduce rsize,wsize for interfaces that consistently 618 * drop fragments of long UDP messages. (i.e. wd8003). 619 * You can always change these later via remount. 620 */ 621 args->flags |= NFSMNT_WSIZE | NFSMNT_RSIZE; 622 args->wsize = NFS_BOOT_RWSIZE; 623 args->rsize = NFS_BOOT_RWSIZE; 624 #endif 625 626 /* 627 * Find the pathname part of the "server:pathname" 628 * string left in ndm->ndm_host by nfs_boot_init. 629 */ 630 pathname = strchr(ndm->ndm_host, ':'); 631 if (pathname == 0) { 632 printf("nfs_boot: getfh - no pathname\n"); 633 return (EIO); 634 } 635 pathname++; 636 637 /* 638 * Get file handle using RPC to mountd/mount 639 */ 640 sin = (struct sockaddr_in *)&ndm->ndm_saddr; 641 error = md_mount(sin, pathname, args, l); 642 if (error) { 643 printf("nfs_boot: mountd `%s', error=%d\n", 644 ndm->ndm_host, error); 645 return (error); 646 } 647 648 /* Set port number for NFS use. */ 649 /* XXX: NFS port is always 2049, right? */ 650 retry: 651 error = krpc_portmap(sin, NFS_PROG, 652 (args->flags & NFSMNT_NFSV3) ? NFS_VER3 : NFS_VER2, 653 (args->sotype == SOCK_STREAM) ? IPPROTO_TCP : IPPROTO_UDP, 654 &port, l); 655 if (port == htons(0)) 656 error = EIO; 657 if (error) { 658 if (args->sotype == SOCK_STREAM) { 659 args->sotype = SOCK_DGRAM; 660 goto retry; 661 } 662 printf("nfs_boot: portmap NFS, error=%d\n", error); 663 return (error); 664 } 665 sin->sin_port = port; 666 return (0); 667 } 668 669 670 /* 671 * RPC: mountd/mount 672 * Given a server pathname, get an NFS file handle. 673 * Also, sets sin->sin_port to the NFS service port. 674 * 675 * mdsin mountd server address 676 */ 677 static int 678 md_mount(struct sockaddr_in *mdsin, char *path, 679 struct nfs_args *argp, struct lwp *lwp) 680 { 681 /* The RPC structures */ 682 struct rdata { 683 u_int32_t errno; 684 union { 685 u_int8_t v2fh[NFSX_V2FH]; 686 struct { 687 u_int32_t fhlen; 688 u_int8_t fh[1]; 689 } v3fh; 690 } fh; 691 } *rdata; 692 struct mbuf *m; 693 u_int8_t *fh; 694 int minlen, error; 695 int mntver; 696 697 mntver = (argp->flags & NFSMNT_NFSV3) ? 3 : 2; 698 do { 699 /* 700 * Get port number for MOUNTD. 701 */ 702 error = krpc_portmap(mdsin, RPCPROG_MNT, mntver, 703 IPPROTO_UDP, &mdsin->sin_port, lwp); 704 if (error) 705 continue; 706 707 /* This mbuf is consumed by krpc_call. */ 708 m = xdr_string_encode(path, strlen(path)); 709 if (m == NULL) 710 return ENOMEM; 711 712 /* Do RPC to mountd. */ 713 error = krpc_call(mdsin, RPCPROG_MNT, mntver, 714 RPCMNT_MOUNT, &m, NULL, lwp); 715 if (error != EPROGMISMATCH) 716 break; 717 /* Try lower version of mountd. */ 718 } while (--mntver >= 1); 719 if (error) { 720 printf("nfs_boot: mountd error=%d\n", error); 721 return error; 722 } 723 if (mntver != 3) 724 argp->flags &= ~NFSMNT_NFSV3; 725 726 /* The reply might have only the errno. */ 727 if (m->m_len < 4) 728 goto bad; 729 /* Have at least errno, so check that. */ 730 rdata = mtod(m, struct rdata *); 731 error = fxdr_unsigned(u_int32_t, rdata->errno); 732 if (error) 733 goto out; 734 735 /* Have errno==0, so the fh must be there. */ 736 if (mntver == 3) { 737 argp->fhsize = fxdr_unsigned(u_int32_t, rdata->fh.v3fh.fhlen); 738 if (argp->fhsize > NFSX_V3FHMAX) 739 goto bad; 740 minlen = 2 * sizeof(u_int32_t) + argp->fhsize; 741 } else { 742 argp->fhsize = NFSX_V2FH; 743 minlen = sizeof(u_int32_t) + argp->fhsize; 744 } 745 746 if (m->m_len < minlen) { 747 m = m_pullup(m, minlen); 748 if (m == NULL) 749 return(EBADRPC); 750 rdata = mtod(m, struct rdata *); 751 } 752 753 fh = (mntver == 3) ? 754 rdata->fh.v3fh.fh : rdata->fh.v2fh; 755 memcpy(argp->fh, fh, argp->fhsize); 756 757 goto out; 758 759 bad: 760 error = EBADRPC; 761 762 out: 763 m_freem(m); 764 return error; 765 } 766