sbin/umount/umount.c

   1 /*-
   2  * Copyright (c) 1980, 1989, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the University nor the names of its contributors
  14  *    may be used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * @(#) Copyright (c) 1980, 1989, 1993 The Regents of the University of California.  All rights reserved.
  30  * @(#)umount.c 8.8 (Berkeley) 5/8/95
  31  * $FreeBSD: src/sbin/umount/umount.c,v 1.28 2001/10/13 02:04:54 iedowse Exp $
  32  */
  33
  34 #include <sys/param.h>
  35 #include <sys/mount.h>
  36 #include <sys/socket.h>
  37
  38 #include <netdb.h>
  39 #include <rpc/rpc.h>
  40 #include <nfs/rpcv2.h>
  41
  42 #include <err.h>
  43 #include <fstab.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48
  49 #include "mounttab.h"
  50
  51 #define ISDOT(x)        ((x)[0] == '.' && (x)[1] == '\0')
  52 #define ISDOTDOT(x)     ((x)[0] == '.' && (x)[1] == '.' && (x)[2] == '\0')
  53
  54 typedef enum { MNTON, MNTFROM, NOTHING } mntwhat;
  55 typedef enum { MARK, UNMARK, NAME, COUNT, FREE } dowhat;
  56
  57 struct  addrinfo *nfshost_ai = NULL;
  58 int     fflag, vflag;
  59 char   *nfshost;
  60
  61 void     checkmntlist (char *, char **, char **, char **);
  62 int      checkvfsname (const char *, char **);
  63 char    *getmntname (const char *, const char *,
  64          mntwhat, char **, dowhat);
  65 char    *getrealname(char *, char *resolved_path);
  66 char   **makevfslist (const char *);
  67 int      mntinfo (struct statfs **);
  68 int      namematch (struct addrinfo *);
  69 int      sacmp (struct sockaddr *, struct sockaddr *);
  70 int      umountall (char **);
  71 int      checkname (char *, char **);
  72 int      umountfs (char *, char *, char *);
  73 void     usage (void);
  74 int      xdr_dir (XDR *, char *);
  75
  76 int
  77 main(int argc, char *argv[])
  78 {
  79         int all, errs, ch, mntsize, error;
  80         char **typelist = NULL, *mntonname, *mntfromname;
  81         char *type, *mntfromnamerev, *mntonnamerev;
  82         struct statfs *mntbuf;
  83         struct addrinfo hints;
  84
  85         all = errs = 0;
  86         while ((ch = getopt(argc, argv, "AaF:fh:t:v")) != -1) {
  87                 switch (ch) {
  88                 case 'A':
  89                         all = 2;
  90                         break;
  91                 case 'a':
  92                         all = 1;
  93                         break;
  94                 case 'F':
  95                         setfstab(optarg);
  96                         break;
  97                 case 'f':
  98                         fflag = MNT_FORCE;
  99                         break;
 100                 case 'h':       /* -h implies -A. */
 101                         all = 2;
 102                         nfshost = optarg;
 103                         break;
 104                 case 't':
 105                         if (typelist != NULL)
 106                                 err(1, "only one -t option may be specified");
 107                         typelist = makevfslist(optarg);
 108                         break;
 109                 case 'v':
 110                         vflag = 1;
 111                         break;
 112                 default:
 113                         usage();
 114                         /* NOTREACHED */
 115                 }
 116         }
 117         argc -= optind;
 118         argv += optind;
 119
 120         if ((argc == 0 && !all) || (argc != 0 && all))
 121                 usage();
 122
 123         /* -h implies "-t nfs" if no -t flag. */
 124         if ((nfshost != NULL) && (typelist == NULL))
 125                 typelist = makevfslist("nfs");
 126
 127         if (nfshost != NULL) {
 128                 memset(&hints, 0, sizeof hints);
 129                 error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai);
 130                 if (error)
 131                         errx(1, "%s: %s", nfshost, gai_strerror(error));
 132         }
 133
 134         switch (all) {
 135         case 2:
 136                 if ((mntsize = mntinfo(&mntbuf)) <= 0)
 137                         break;
 138                 /*
 139                  * We unmount the nfs-mounts in the reverse order
 140                  * that they were mounted.
 141                  */
 142                 for (errs = 0, mntsize--; mntsize > 0; mntsize--) {
 143                         if (checkvfsname(mntbuf[mntsize].f_fstypename,
 144                             typelist))
 145                                 continue;
 146                         /*
 147                          * Check if a mountpoint is laid over by another mount.
 148                          * A warning will be printed to stderr if this is
 149                          * the case. The laid over mount remains unmounted.
 150                          */
 151                         mntonname = mntbuf[mntsize].f_mntonname;
 152                         mntfromname = mntbuf[mntsize].f_mntfromname;
 153                         mntonnamerev = getmntname(getmntname(mntonname,
 154                             NULL, MNTFROM, &type, NAME), NULL,
 155                             MNTON, &type, NAME);
 156
 157                         mntfromnamerev = getmntname(mntonnamerev,
 158                             NULL, MNTFROM, &type, NAME);
 159
 160                         if (strcmp(mntonnamerev, mntonname) == 0 &&
 161                             strcmp(mntfromnamerev, mntfromname ) != 0)
 162                                 warnx("cannot umount %s, %s\n        "
 163                                     "is mounted there, umount it first",
 164                                     mntonname, mntfromnamerev);
 165
 166                         if (checkname(mntbuf[mntsize].f_mntonname,
 167                             typelist) != 0)
 168                                 errs = 1;
 169                 }
 170                 free(mntbuf);
 171                 break;
 172         case 1:
 173                 if (setfsent() == 0)
 174                         err(1, "%s", getfstab());
 175                 errs = umountall(typelist);
 176                 break;
 177         case 0:
 178                 for (errs = 0; *argv != NULL; ++argv)
 179                         if (checkname(*argv, typelist) != 0)
 180                                 errs = 1;
 181                 break;
 182         }
 183         getmntname(NULL, NULL, NOTHING, NULL, FREE);
 184         exit(errs);
 185 }
 186
 187 int
 188 umountall(char **typelist)
 189 {
 190         struct vfsconf vfc;
 191         struct fstab *fs;
 192         int rval;
 193         char *cp;
 194         static int firstcall = 1;
 195
 196         if ((fs = getfsent()) != NULL)
 197                 firstcall = 0;
 198         else if (firstcall)
 199                 errx(1, "fstab reading failure");
 200         else
 201                 return (0);
 202         do {
 203                 /* Ignore the root. */
 204                 if (strcmp(fs->fs_file, "/") == 0)
 205                         continue;
 206                 /*
 207                  * !!!
 208                  * Historic practice: ignore unknown FSTAB_* fields.
 209                  */
 210                 if (strcmp(fs->fs_type, FSTAB_RW) &&
 211                     strcmp(fs->fs_type, FSTAB_RO) &&
 212                     strcmp(fs->fs_type, FSTAB_RQ))
 213                         continue;
 214                 /* Ignore unknown file system types. */
 215                 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1)
 216                         continue;
 217                 if (checkvfsname(fs->fs_vfstype, typelist))
 218                         continue;
 219
 220                 /*
 221                  * We want to unmount the file systems in the reverse order
 222                  * that they were mounted.  So, we save off the file name
 223                  * in some allocated memory, and then call recursively.
 224                  */
 225                 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL)
 226                         err(1, "malloc failed");
 227                 strcpy(cp, fs->fs_file);
 228                 rval = umountall(typelist);
 229                 rval = checkname(cp, typelist) || rval;
 230                 free(cp);
 231                 return (rval);
 232         } while ((fs = getfsent()) != NULL);
 233         return (0);
 234 }
 235
 236 /*
 237  * Do magic checks on mountpoint and device or hand over
 238  * it to unmount(2) if everything fails.
 239  */
 240 int
 241 checkname(char *name, char **typelist)
 242 {
 243         size_t len;
 244         int speclen;
 245         char *mntonname, *mntfromname;
 246         char *mntfromnamerev;
 247         char *resolved, realname[MAXPATHLEN];
 248         char *type, *hostp, *delimp, *origname;
 249         char none[] = "none";
 250
 251         len = 0;
 252         mntfromname = mntonname = delimp = hostp = NULL;
 253
 254         /*
 255          * 1. Check if the name exists in the mounttable.
 256          */
 257         checkmntlist(name, &mntfromname, &mntonname, &type);
 258         if (mntfromname == NULL && mntonname == NULL) {
 259                 checkmntlist(getdevpath(name, 0), &mntfromname,
 260                              &mntonname, &type);
 261         }
 262
 263         /*
 264          * 2. Remove trailing slashes if there are any. After that
 265          * we look up the name in the mounttable again.
 266          */
 267         if (mntfromname == NULL && mntonname == NULL) {
 268                 speclen = strlen(name);
 269                 for (speclen = strlen(name);
 270                     speclen > 1 && name[speclen - 1] == '/';
 271                     speclen--)
 272                         name[speclen - 1] = '\0';
 273                 checkmntlist(name, &mntfromname, &mntonname, &type);
 274                 resolved = name;
 275                 /* Save off original name in origname */
 276                 if ((origname = strdup(name)) == NULL)
 277                         err(1, "strdup");
 278                 /*
 279                  * 3. Check if the deprecated nfs-syntax with an '@'
 280                  * has been used and translate it to the ':' syntax.
 281                  * Look up the name in the mounttable again.
 282                  */
 283                 if (mntfromname == NULL && mntonname == NULL) {
 284                         if ((delimp = strrchr(name, '@')) != NULL) {
 285                                 hostp = delimp + 1;
 286                                 if (*hostp != '\0') {
 287                                         /*
 288                                          * Make both '@' and ':'
 289                                          * notations equal
 290                                          */
 291                                         char *host = strdup(hostp);
 292                                         len = strlen(hostp);
 293                                         if (host == NULL)
 294                                                 err(1, "strdup");
 295                                         memmove(name + len + 1, name,
 296                                             (size_t)(delimp - name));
 297                                         name[len] = ':';
 298                                         memmove(name, host, len);
 299                                         free(host);
 300                                 }
 301                                 for (speclen = strlen(name);
 302                                     speclen > 1 && name[speclen - 1] == '/';
 303                                     speclen--)
 304                                         name[speclen - 1] = '\0';
 305                                 name[len + speclen + 1] = '\0';
 306                                 checkmntlist(name, &mntfromname,
 307                                     &mntonname, &type);
 308                                 resolved = name;
 309                         }
 310                         /*
 311                          * 4. Check if a relative mountpoint has been
 312                          * specified. This should happen as last check,
 313                          * the order is important. To prevent possible
 314                          * nfs-hangs, we just call realpath(3) on the
 315                          * basedir of mountpoint and add the dirname again.
 316                          * Check the name in mounttable one last time.
 317                          */
 318                         if (mntfromname == NULL && mntonname == NULL) {
 319                                 strcpy(name, origname);
 320                                 if ((getrealname(name, realname)) != NULL) {
 321                                         checkmntlist(realname,
 322                                             &mntfromname, &mntonname, &type);
 323                                         resolved = realname;
 324                                 }
 325                                 /*
 326                                  * 5. All tests failed, just hand over the
 327                                  * mountpoint to the kernel, maybe the statfs
 328                                  * structure has been truncated or is not
 329                                  * useful anymore because of a chroot(2).
 330                                  * Please note that nfs will not be able to
 331                                  * notify the nfs-server about unmounting.
 332                                  * These things can change in future when the
 333                                  * fstat structure get's more reliable,
 334                                  * but at the moment we cannot thrust it.
 335                                  */
 336                                 if (mntfromname == NULL && mntonname == NULL) {
 337                                         strcpy(name, origname);
 338                                         if (umountfs(NULL, origname,
 339                                             none) == 0) {
 340                                                 warnx("%s not found in "
 341                                                     "mount table, "
 342                                                     "unmounted it anyway",
 343                                                     origname);
 344                                                 free(origname);
 345                                                 return (0);
 346                                         } else
 347                                                 free(origname);
 348                                                 return (1);
 349                                 }
 350                         }
 351                 }
 352                 free(origname);
 353         } else
 354                 resolved = name;
 355
 356         if (checkvfsname(type, typelist))
 357                 return (1);
 358
 359         /*
 360          * Check if the reverse entrys of the mounttable are really the
 361          * same as the normal ones.
 362          */
 363         if ((mntfromnamerev = strdup(getmntname(getmntname(mntfromname,
 364             NULL, MNTON, &type, NAME), NULL, MNTFROM, &type, NAME))) == NULL)
 365                 err(1, "strdup");
 366         /*
 367          * Mark the uppermost mount as unmounted.
 368          */
 369         getmntname(mntfromname, mntonname, NOTHING, &type, MARK);
 370         /*
 371          * If several equal mounts are in the mounttable, check the order
 372          * and warn the user if necessary.
 373          */
 374         if (strcmp(mntfromnamerev, mntfromname ) != 0 &&
 375             strcmp(resolved, mntonname) != 0) {
 376                 warnx("cannot umount %s, %s\n        "
 377                     "is mounted there, umount it first",
 378                     mntonname, mntfromnamerev);
 379
 380                 /* call getmntname again to set mntcheck[i] to 0 */
 381                 getmntname(mntfromname, mntonname,
 382                     NOTHING, &type, UNMARK);
 383                 return (1);
 384         }
 385         free(mntfromnamerev);
 386         return (umountfs(mntfromname, mntonname, type));
 387 }
 388
 389 /*
 390  * NFS stuff and unmount(2) call
 391  */
 392 int
 393 umountfs(char *mntfromname, char *mntonname, char *type)
 394 {
 395         enum clnt_stat clnt_stat;
 396         struct timeval try;
 397         struct addrinfo *ai, hints;
 398         int do_rpc;
 399         CLIENT *clp;
 400         char *nfsdirname, *orignfsdirname;
 401         char *hostp, *delimp;
 402
 403         ai = NULL;
 404         do_rpc = 0;
 405         hostp = NULL;
 406         nfsdirname = delimp = orignfsdirname = NULL;
 407         memset(&hints, 0, sizeof hints);
 408
 409         if (strcmp(type, "nfs") == 0) {
 410                 if ((nfsdirname = strdup(mntfromname)) == NULL)
 411                         err(1, "strdup");
 412                 orignfsdirname = nfsdirname;
 413                 if ((delimp = strrchr(nfsdirname, ':')) != NULL) {
 414                         *delimp = '\0';
 415                         hostp = nfsdirname;
 416                         getaddrinfo(hostp, NULL, &hints, &ai);
 417                         if (ai == NULL) {
 418                                 warnx("can't get net id for host");
 419                         }
 420                         nfsdirname = delimp + 1;
 421                 }
 422
 423                 /*
 424                  * Check if we have to start the rpc-call later.
 425                  * If there are still identical nfs-names mounted,
 426                  * we skip the rpc-call. Obviously this has to
 427                  * happen before unmount(2), but it should happen
 428                  * after the previous namecheck.
 429                  * A non-NULL return means that this is the last
 430                  * mount from mntfromname that is still mounted.
 431                  */
 432                 if (getmntname(mntfromname, NULL, NOTHING, &type, COUNT)
 433                      != NULL)
 434                         do_rpc = 1;
 435         }
 436
 437         if (!namematch(ai))
 438                 return (1);
 439         if (unmount(mntonname, fflag) != 0 ) {
 440                 warn("unmount of %s failed", mntonname);
 441                 return (1);
 442         }
 443         if (vflag)
 444                 printf("%s: unmount from %s\n", mntfromname, mntonname);
 445         /*
 446          * Report to mountd-server which nfsname
 447          * has been unmounted.
 448          */
 449         if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) {
 450                 clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, "udp");
 451                 if (clp  == NULL) {
 452                         warnx("%s: %s", hostp,
 453                             clnt_spcreateerror("RPCPROG_MNT"));
 454                         return (1);
 455                 }
 456                 clp->cl_auth = authsys_create_default();
 457                 try.tv_sec = 20;
 458                 try.tv_usec = 0;
 459                 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, (xdrproc_t)xdr_dir,
 460                     nfsdirname, (xdrproc_t)xdr_void, (caddr_t)0, try);
 461                 if (clnt_stat != RPC_SUCCESS) {
 462                         warnx("%s: %s", hostp,
 463                             clnt_sperror(clp, "RPCMNT_UMOUNT"));
 464                         return (1);
 465                 }
 466                 /*
 467                  * Remove the unmounted entry from /var/db/mounttab.
 468                  */
 469                 if (read_mtab()) {
 470                         clean_mtab(hostp, nfsdirname, vflag);
 471                         if(!write_mtab(vflag))
 472                                 warnx("cannot remove mounttab entry %s:%s",
 473                                     hostp, nfsdirname);
 474                         free_mtab();
 475                 }
 476                 free(orignfsdirname);
 477                 auth_destroy(clp->cl_auth);
 478                 clnt_destroy(clp);
 479         }
 480         return (0);
 481 }
 482
 483 char *
 484 getmntname(const char *fromname, const char *onname,
 485     mntwhat what, char **type, dowhat mark)
 486 {
 487         static struct statfs *mntbuf;
 488         static int mntsize = 0;
 489         static char *mntcheck = NULL;
 490         static char *mntcount = NULL;
 491         int i, count;
 492
 493         if (mntsize <= 0) {
 494                 if ((mntsize = mntinfo(&mntbuf)) <= 0)
 495                         return (NULL);
 496         }
 497         if (mntcheck == NULL) {
 498                 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL ||
 499                     (mntcount = calloc(mntsize + 1, sizeof(int))) == NULL)
 500                         err(1, "calloc");
 501         }
 502         /*
 503          * We want to get the file systems in the reverse order
 504          * that they were mounted. Mounted and unmounted filesystems
 505          * are marked or unmarked in a table called 'mntcheck'.
 506          * Unmount(const char *dir, int flags) does only take the
 507          * mountpoint as argument, not the destination. If we don't pay
 508          * attention to the order, it can happen that a overlaying
 509          * filesystem get's unmounted instead of the one the user
 510          * has choosen.
 511          */
 512         switch (mark) {
 513         case NAME:
 514                 /* Return only the specific name */
 515                 for (i = mntsize - 1; i >= 0; i--) {
 516                         if (fromname != NULL && what == MNTON &&
 517                             !strcmp(mntbuf[i].f_mntfromname, fromname) &&
 518                             mntcheck[i] != 1) {
 519                                 if (type)
 520                                         *type = mntbuf[i].f_fstypename;
 521                                 return (mntbuf[i].f_mntonname);
 522                         }
 523                         if (fromname != NULL && what == MNTFROM &&
 524                             !strcmp(mntbuf[i].f_mntonname, fromname) &&
 525                             mntcheck[i] != 1) {
 526                                 if (type)
 527                                         *type = mntbuf[i].f_fstypename;
 528                                 return (mntbuf[i].f_mntfromname);
 529                         }
 530                 }
 531                 return (NULL);
 532         case MARK:
 533                 /* Mark current mount with '1' and return name */
 534                 for (i = mntsize - 1; i >= 0; i--) {
 535                         if (mntcheck[i] == 0 &&
 536                             (strcmp(mntbuf[i].f_mntonname, onname) == 0) &&
 537                             (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) {
 538                                 mntcheck[i] = 1;
 539                                 return (mntbuf[i].f_mntonname);
 540                         }
 541                 }
 542                 return (NULL);
 543         case UNMARK:
 544                 /* Unmark current mount with '0' and return name */
 545                 for (i = 0; i < mntsize; i++) {
 546                         if (mntcheck[i] == 1 &&
 547                             (strcmp(mntbuf[i].f_mntonname, onname) == 0) &&
 548                             (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) {
 549                                 mntcheck[i] = 0;
 550                                 return (mntbuf[i].f_mntonname);
 551                         }
 552                 }
 553                 return (NULL);
 554         case COUNT:
 555                 /* Count the equal mntfromnames */
 556                 count = 0;
 557                 for (i = mntsize - 1; i >= 0; i--) {
 558                         if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)
 559                                 count++;
 560                 }
 561                 /* Mark the already unmounted mounts and return
 562                  * mntfromname if count <= 1. Else return NULL.
 563                  */
 564                 for (i = mntsize - 1; i >= 0; i--) {
 565                         if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) {
 566                                 if (mntcount[i] == 1)
 567                                         count--;
 568                                 else {
 569                                         mntcount[i] = 1;
 570                                         break;
 571                                 }
 572                         }
 573                 }
 574                 if (count <= 1)
 575                         return (mntbuf[i].f_mntonname);
 576                 else
 577                         return (NULL);
 578         case FREE:
 579                 free(mntbuf);
 580                 free(mntcheck);
 581                 free(mntcount);
 582                 return (NULL);
 583         default:
 584                 return (NULL);
 585         }
 586 }
 587
 588 int
 589 sacmp(struct sockaddr *sa1, struct sockaddr *sa2)
 590 {
 591         void *p1, *p2;
 592         int len;
 593
 594         if (sa1->sa_family != sa2->sa_family)
 595                 return (1);
 596
 597         switch (sa1->sa_family) {
 598         case AF_INET:
 599                 p1 = &((struct sockaddr_in *)sa1)->sin_addr;
 600                 p2 = &((struct sockaddr_in *)sa2)->sin_addr;
 601                 len = 4;
 602                 break;
 603         case AF_INET6:
 604                 p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr;
 605                 p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr;
 606                 len = 16;
 607                 if (((struct sockaddr_in6 *)sa1)->sin6_scope_id !=
 608                     ((struct sockaddr_in6 *)sa2)->sin6_scope_id)
 609                         return (1);
 610                 break;
 611         default:
 612                 return (1);
 613         }
 614
 615         return memcmp(p1, p2, len);
 616 }
 617
 618 int
 619 namematch(struct addrinfo *ai)
 620 {
 621         struct addrinfo *aip;
 622
 623         if (nfshost == NULL || nfshost_ai == NULL)
 624                 return (1);
 625
 626         while (ai != NULL) {
 627                 aip = nfshost_ai;
 628                 while (aip != NULL) {
 629                         if (sacmp(ai->ai_addr, aip->ai_addr) == 0)
 630                                 return (1);
 631                         aip = aip->ai_next;
 632                 }
 633                 ai = ai->ai_next;
 634         }
 635
 636         return (0);
 637 }
 638
 639 void
 640 checkmntlist(char *name, char **fromname, char **onname, char **type)
 641 {
 642
 643         *fromname = getmntname(name, NULL, MNTFROM, type, NAME);
 644         if (*fromname == NULL) {
 645                 *onname = getmntname(name, NULL, MNTON, type, NAME);
 646                 if (*onname != NULL)
 647                         *fromname = name;
 648         } else
 649                 *onname = name;
 650 }
 651
 652 int
 653 mntinfo(struct statfs **mntbuf)
 654 {
 655         static struct statfs *origbuf;
 656         size_t bufsize;
 657         int mntsize;
 658
 659         mntsize = getfsstat(NULL, 0, MNT_NOWAIT);
 660         if (mntsize <= 0)
 661                 return (0);
 662         bufsize = (mntsize + 1) * sizeof(struct statfs);
 663         if ((origbuf = malloc(bufsize)) == NULL)
 664                 err(1, "malloc");
 665         mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT);
 666         *mntbuf = origbuf;
 667         return (mntsize);
 668 }
 669
 670 char *
 671 getrealname(char *name, char *realname)
 672 {
 673         char *dirname;
 674         int havedir;
 675         size_t baselen;
 676         size_t dirlen;
 677
 678         dirname = NULL;
 679         havedir = 0;
 680         if (*name == '/') {
 681                 if (ISDOT(name + 1) || ISDOTDOT(name + 1))
 682                         strcpy(realname, "/");
 683                 else {
 684                         if ((dirname = strrchr(name + 1, '/')) == NULL)
 685                                 snprintf(realname, MAXPATHLEN, "%s", name);
 686                         else
 687                                 havedir = 1;
 688                 }
 689         } else {
 690                 if (ISDOT(name) || ISDOTDOT(name))
 691                         realpath(name, realname);
 692                 else {
 693                         if ((dirname = strrchr(name, '/')) == NULL) {
 694                                 if ((realpath(name, realname)) == NULL)
 695                                         return (NULL);
 696                         } else
 697                                 havedir = 1;
 698                 }
 699         }
 700         if (havedir) {
 701                 *dirname++ = '\0';
 702                 if (ISDOT(dirname)) {
 703                         *dirname = '\0';
 704                         if ((realpath(name, realname)) == NULL)
 705                                 return (NULL);
 706                 } else if (ISDOTDOT(dirname)) {
 707                         *--dirname = '/';
 708                         if ((realpath(name, realname)) == NULL)
 709                                 return (NULL);
 710                 } else {
 711                         if ((realpath(name, realname)) == NULL)
 712                                 return (NULL);
 713                         baselen = strlen(realname);
 714                         dirlen = strlen(dirname);
 715                         if (baselen + dirlen + 1 > MAXPATHLEN)
 716                                 return (NULL);
 717                         if (realname[1] == '\0') {
 718                                 memmove(realname + 1, dirname, dirlen);
 719                                 realname[dirlen + 1] = '\0';
 720                         } else {
 721                                 realname[baselen] = '/';
 722                                 memmove(realname + baselen + 1,
 723                                     dirname, dirlen);
 724                                 realname[baselen + dirlen + 1] = '\0';
 725                         }
 726                 }
 727         }
 728         return (realname);
 729 }
 730
 731 /*
 732  * xdr routines for mount rpc's
 733  */
 734 int
 735 xdr_dir(XDR *xdrsp, char *dirp)
 736 {
 737
 738         return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN));
 739 }
 740
 741 void
 742 usage(void)
 743 {
 744
 745         fprintf(stderr, "%s\n%s\n",
 746             "usage: umount [-fv] special | node",
 747             "       umount -a | -A [-F fstab] [-fv] [-h host] [-t type]");
 748         exit(1);
 749 }