umount.c revision 52340
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. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University nor the names of its contributors 18 * may be used to endorse or promote products derived from this software 19 * without specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34#ifndef lint 35static const char copyright[] = 36"@(#) Copyright (c) 1980, 1989, 1993\n\ 37 The Regents of the University of California. All rights reserved.\n"; 38#endif /* not lint */ 39 40#ifndef lint 41#if 0 42static char sccsid[] = "@(#)umount.c 8.8 (Berkeley) 5/8/95"; 43#endif 44static const char rcsid[] = 45 "$FreeBSD: head/sbin/umount/umount.c 52340 1999-10-17 16:26:58Z green $"; 46#endif /* not lint */ 47 48#include <sys/param.h> 49#include <sys/mount.h> 50 51#include <netdb.h> 52#include <rpc/rpc.h> 53#include <nfs/rpcv2.h> 54 55#include <err.h> 56#include <fstab.h> 57#include <stdio.h> 58#include <stdlib.h> 59#include <string.h> 60#include <unistd.h> 61 62#define ISDOT(x) ((x)[0] == '.' && (x)[1] == '\0') 63#define ISDOTDOT(x) ((x)[0] == '.' && (x)[1] == '.' && (x)[2] == '\0') 64 65typedef enum { MNTON, MNTFROM, NOTHING } mntwhat; 66typedef enum { MARK, UNMARK, NAME, COUNT, FREE } dowhat; 67 68int fflag, vflag, count; 69char *nfshost; 70 71void checkmntlist (char *, char **, char **, char **); 72int checkvfsname (const char *, char **); 73char *getmntname (const char *, const char *, 74 mntwhat, char **, dowhat); 75char *getrealname(char *, char *resolved_path); 76char **makevfslist (const char *); 77size_t mntinfo (struct statfs **); 78int namematch (struct hostent *); 79int selected (int); 80int umountall (char **); 81int umountfs (char *, char **); 82void usage (void); 83int xdr_dir (XDR *, char *); 84 85int 86main(int argc, char *argv[]) 87{ 88 int all, errs, ch, mntsize; 89 char **typelist = NULL, *mntonname, *mntfromname; 90 char *type, *mntfromnamerev, *mntonnamerev; 91 struct statfs *mntbuf; 92 93 /* Start disks transferring immediately. */ 94 sync(); 95 96 all = count = errs = 0; 97 while ((ch = getopt(argc, argv, "Aafh:t:v")) != -1) 98 switch (ch) { 99 case 'A': 100 all = 2; 101 break; 102 case 'a': 103 all = 1; 104 break; 105 case 'f': 106 fflag = MNT_FORCE; 107 break; 108 case 'h': /* -h implies -A. */ 109 all = 2; 110 nfshost = optarg; 111 break; 112 case 't': 113 if (typelist != NULL) 114 err(1, "only one -t option may be specified"); 115 typelist = makevfslist(optarg); 116 break; 117 case 'v': 118 vflag = 1; 119 break; 120 default: 121 usage(); 122 /* NOTREACHED */ 123 } 124 argc -= optind; 125 argv += optind; 126 127 if ((argc == 0 && !all) || (argc != 0 && all)) 128 usage(); 129 130 /* -h implies "-t nfs" if no -t flag. */ 131 if ((nfshost != NULL) && (typelist == NULL)) 132 typelist = makevfslist("nfs"); 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 (umountfs(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", _PATH_FSTAB); 175 errs = umountall(typelist); 176 break; 177 case 0: 178 for (errs = 0; *argv != NULL; ++argv) 179 if (umountfs(*argv, typelist) != 0) 180 errs = 1; 181 break; 182 } 183 (void)getmntname(NULL, NULL, NOTHING, NULL, FREE); 184 exit(errs); 185} 186 187int 188umountall(char **typelist) 189{ 190 struct fstab *fs; 191 int rval; 192 char *cp; 193 struct vfsconf vfc; 194 195 if ((fs = getfsent()) != NULL) 196 errx(1, "fstab reading failure"); 197 do { 198 /* Ignore the root. */ 199 if (strcmp(fs->fs_file, "/") == 0) 200 continue; 201 /* 202 * !!! 203 * Historic practice: ignore unknown FSTAB_* fields. 204 */ 205 if (strcmp(fs->fs_type, FSTAB_RW) && 206 strcmp(fs->fs_type, FSTAB_RO) && 207 strcmp(fs->fs_type, FSTAB_RQ)) 208 continue; 209 /* If an unknown file system type, complain. */ 210 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1) { 211 warnx("%s: unknown mount type", fs->fs_vfstype); 212 continue; 213 } 214 if (checkvfsname(fs->fs_vfstype, typelist)) 215 continue; 216 217 /* 218 * We want to unmount the file systems in the reverse order 219 * that they were mounted. So, we save off the file name 220 * in some allocated memory, and then call recursively. 221 */ 222 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL) 223 err(1, "malloc failed"); 224 (void)strcpy(cp, fs->fs_file); 225 rval = umountall(typelist); 226 return (umountfs(cp, typelist) || rval); 227 } while ((fs = getfsent()) != NULL); 228 free(cp); 229 return (0); 230} 231 232int 233umountfs(char *name, char **typelist) 234{ 235 enum clnt_stat clnt_stat; 236 struct hostent *hp; 237 struct sockaddr_in saddr; 238 struct timeval pertry, try; 239 CLIENT *clp; 240 size_t len; 241 int so, speclen; 242 char *mntonname, *mntfromname; 243 char *mntfromnamerev, *mntonnamerev; 244 char *nfsdirname, *orignfsdirname; 245 char *resolved, realname[MAXPATHLEN + 1]; 246 char *type, *delimp, *hostp, *origname; 247 248 mntfromname = mntonname = delimp = hostp = orignfsdirname = NULL; 249 250 /* 251 * 1. Check if the name exists in the mounttable. 252 */ 253 (void)checkmntlist(name, &mntfromname, &mntonname, &type); 254 /* 255 * 2. Remove trailing slashes if there are any. After that 256 * we look up the name in the mounttable again. 257 */ 258 if (mntfromname == NULL && mntonname == NULL) { 259 speclen = strlen(name); 260 for (speclen = strlen(name); 261 speclen > 1 && name[speclen - 1] == '/'; 262 speclen--) 263 name[speclen - 1] = '\0'; 264 (void)checkmntlist(name, &mntfromname, &mntonname, &type); 265 resolved = name; 266 /* Save off original name in origname */ 267 if ((origname = strdup(name)) == NULL) 268 err(1, "strdup"); 269 /* 270 * 3. Check if the deprecated nfs-syntax with an '@' 271 * has been used and translate it to the ':' syntax. 272 * Look up the name in the mounttable again. 273 */ 274 if (mntfromname == NULL && mntonname == NULL) { 275 if ((delimp = strrchr(name, '@')) != NULL) { 276 hostp = delimp + 1; 277 if (*hostp != '\0') { 278 /* 279 * Make both '@' and ':' 280 * notations equal 281 */ 282 char *host = strdup(hostp); 283 len = strlen(hostp); 284 if (host == NULL) 285 err(1, "strdup"); 286 memmove(name + len + 1, name, 287 (size_t)(delimp - name)); 288 name[len] = ':'; 289 memmove(name, host, len); 290 free(host); 291 } 292 for (speclen = strlen(name); 293 speclen > 1 && name[speclen - 1] == '/'; 294 speclen--) 295 name[speclen - 1] = '\0'; 296 name[len + speclen + 1] = '\0'; 297 (void)checkmntlist(name, &mntfromname, 298 &mntonname, &type); 299 resolved = name; 300 } 301 /* 302 * 4. Check if a relative mountpoint has been 303 * specified. This should happen as last check, 304 * the order is important. To prevent possible 305 * nfs-hangs, we just call realpath(3) on the 306 * basedir of mountpoint and add the dirname again. 307 * Check the name in mounttable one last time. 308 */ 309 if (mntfromname == NULL && mntonname == NULL) { 310 (void)strcpy(name, origname); 311 if ((getrealname(name, realname)) != NULL) { 312 (void)checkmntlist(realname, 313 &mntfromname, &mntonname, &type); 314 resolved = realname; 315 } 316 /* 317 * All tests failed, return to main() 318 */ 319 if (mntfromname == NULL && mntonname == NULL) { 320 (void)strcpy(name, origname); 321 warnx("%s: not currently mounted", 322 origname); 323 free(origname); 324 return (1); 325 } 326 } 327 } 328 free(origname); 329 } else 330 resolved = name; 331 332 if (checkvfsname(type, typelist)) 333 return (1); 334 335 hp = NULL; 336 nfsdirname = NULL; 337 if (!strcmp(type, "nfs")) { 338 if ((nfsdirname = strdup(mntfromname)) == NULL) 339 err(1, "strdup"); 340 orignfsdirname = nfsdirname; 341 if ((delimp = strchr(nfsdirname, ':')) != NULL) { 342 *delimp = '\0'; 343 hostp = nfsdirname; 344 if ((hp = gethostbyname(hostp)) == NULL) { 345 warnx("can't get net id for host"); 346 } 347 nfsdirname = delimp + 1; 348 } 349 } 350 /* 351 * Check if the reverse entrys of the mounttable are really the 352 * same as the normal ones. 353 */ 354 if ((mntfromnamerev = strdup(getmntname(getmntname(mntfromname, 355 NULL, MNTON, &type, NAME), NULL, 356 MNTFROM, &type, NAME))) == NULL) 357 err(1, "strdup"); 358 if ((mntonnamerev = strdup(getmntname(mntfromnamerev, NULL, 359 MNTON, &type, NAME))) == NULL) 360 err(1, "strdup"); 361 /* 362 * Mark the uppermost mount as unmounted. 363 */ 364 (void)getmntname(mntfromnamerev, mntonnamerev, NOTHING, &type, MARK); 365 /* 366 * If several equal mounts are in the mounttable, check the order 367 * and warn the user if necessary. 368 */ 369 if (strcmp(mntfromnamerev, mntfromname ) != 0 && 370 strcmp(resolved, mntonname) != 0) { 371 warnx("cannot umount %s, %s\n " 372 "is mounted there, umount it first", 373 mntonname, mntfromnamerev); 374 375 /* call getmntname again to set mntcheck[i] to 0 */ 376 (void)getmntname(mntfromnamerev, mntonnamerev, 377 NOTHING, &type, UNMARK); 378 return (1); 379 } 380 free(mntonnamerev); 381 free(mntfromnamerev); 382 /* 383 * Check if we have to start the rpc-call later. 384 * If there are still identical nfs-names mounted, 385 * we skip the rpc-call. Obviously this has to 386 * happen before unmount(2), but it should happen 387 * after the previous namecheck. 388 */ 389 if (!strcmp(type, "nfs")) { 390 if (getmntname(mntfromname, NULL, NOTHING, 391 &type, COUNT) == NULL) 392 count = 1; 393 } 394 else 395 count = 0; 396 if (!namematch(hp)) 397 return (1); 398 if (unmount(mntonname, fflag) != 0 ) { 399 warn("unmount of %s failed", mntonname); 400 return (1); 401 } 402 if (vflag) 403 (void)printf("%s: unmount from %s\n", mntfromname, mntonname); 404 /* 405 * Report to mountd-server which nfsname 406 * has been unmounted. 407 */ 408 if (hp != NULL && !(fflag & MNT_FORCE) && count == 0) { 409 memset(&saddr, 0, sizeof(saddr)); 410 saddr.sin_family = AF_INET; 411 saddr.sin_port = 0; 412 memmove(&saddr.sin_addr, hp->h_addr, 413 MIN(hp->h_length, sizeof(saddr.sin_addr))); 414 pertry.tv_sec = 3; 415 pertry.tv_usec = 0; 416 so = RPC_ANYSOCK; 417 if ((clp = clntudp_create(&saddr, 418 RPCPROG_MNT, RPCMNT_VER1, pertry, &so)) == NULL) { 419 clnt_pcreateerror("Cannot MNT PRC"); 420 return (1); 421 } 422 clp->cl_auth = authunix_create_default(); 423 try.tv_sec = 20; 424 try.tv_usec = 0; 425 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, xdr_dir, 426 nfsdirname, xdr_void, (caddr_t)0, try); 427 if (clnt_stat != RPC_SUCCESS) { 428 clnt_perror(clp, "Bad MNT RPC"); 429 return (1); 430 } 431 free(orignfsdirname); 432 auth_destroy(clp->cl_auth); 433 clnt_destroy(clp); 434 } 435 return (0); 436} 437 438char * 439getmntname(const char *fromname, const char *onname, 440 mntwhat what, char **type, dowhat mark) 441{ 442 static struct statfs *mntbuf; 443 static size_t mntsize = 0; 444 static char *mntcheck = NULL; 445 static char *mntcount = NULL; 446 int i, count; 447 448 if (mntsize <= 0) { 449 if ((mntsize = mntinfo(&mntbuf)) <= 0) 450 return (NULL); 451 } 452 if (mntcheck == NULL) { 453 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL || 454 (mntcount = calloc(mntsize + 1, sizeof(int))) == NULL) 455 err(1, "calloc"); 456 } 457 /* 458 * We want to get the file systems in the reverse order 459 * that they were mounted. Mounted and unmounted filesystems 460 * are marked or unmarked in a table called 'mntcheck'. 461 * Unmount(const char *dir, int flags) does only take the 462 * mountpoint as argument, not the destination. If we don't pay 463 * attention to the order, it can happen that a overlaying 464 * filesystem get's unmounted instead of the one the user 465 * has choosen. 466 */ 467 switch (mark) { 468 case NAME: 469 /* Return only the specific name */ 470 for (i = mntsize - 1; i >= 0; i--) { 471 if (fromname != NULL && what == MNTON && 472 !strcmp(mntbuf[i].f_mntfromname, fromname) && 473 mntcheck[i] != 1) { 474 if (type) 475 *type = mntbuf[i].f_fstypename; 476 return (mntbuf[i].f_mntonname); 477 } 478 if (fromname != NULL && what == MNTFROM && 479 !strcmp(mntbuf[i].f_mntonname, fromname) && 480 mntcheck[i] != 1) { 481 if (type) 482 *type = mntbuf[i].f_fstypename; 483 return (mntbuf[i].f_mntfromname); 484 } 485 } 486 return (NULL); 487 case MARK: 488 /* Mark current mount with '1' and return name */ 489 for (i = mntsize - 1; i >= 0; i--) { 490 if (mntcheck[i] == 0 && 491 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 492 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 493 mntcheck[i] = 1; 494 return (mntbuf[i].f_mntonname); 495 } 496 } 497 return (NULL); 498 case UNMARK: 499 /* Unmark current mount with '0' and return name */ 500 for (i = 0; i < mntsize; i++) { 501 if (mntcheck[i] == 1 && 502 (strcmp(mntbuf[i].f_mntonname, onname) == 0) && 503 (strcmp(mntbuf[i].f_mntfromname, fromname) == 0)) { 504 mntcheck[i] = 0; 505 return (mntbuf[i].f_mntonname); 506 } 507 } 508 return (NULL); 509 case COUNT: 510 /* Count the equal mntfromnames */ 511 count = 0; 512 for (i = mntsize - 1; i >= 0; i--) { 513 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) 514 count++; 515 } 516 /* Mark the already unmounted mounts and return 517 * mntfromname if count == 1. Else return NULL. 518 */ 519 for (i = mntsize - 1; i >= 0; i--) { 520 if (strcmp(mntbuf[i].f_mntfromname, fromname) == 0) { 521 if (mntcount[i] == 1) 522 count--; 523 else 524 mntcount[i] = 1; 525 if (count == 1) 526 return (mntbuf[i].f_mntonname); 527 else 528 return (NULL); 529 } 530 } 531 return (NULL); 532 case FREE: 533 free(mntbuf); 534 free(mntcheck); 535 return (NULL); 536 default: 537 return (NULL); 538 } 539} 540 541int 542namematch(struct hostent *hp) 543{ 544 char *cp, **np; 545 546 if ((hp == NULL) || (nfshost == NULL)) 547 return (1); 548 549 if (strcasecmp(nfshost, hp->h_name) == 0) 550 return (1); 551 552 if ((cp = strchr(hp->h_name, '.')) != NULL) { 553 *cp = '\0'; 554 if (strcasecmp(nfshost, hp->h_name) == 0) 555 return (1); 556 } 557 for (np = hp->h_aliases; *np; np++) { 558 if (strcasecmp(nfshost, *np) == 0) 559 return (1); 560 if ((cp = strchr(*np, '.')) != NULL) { 561 *cp = '\0'; 562 if (strcasecmp(nfshost, *np) == 0) 563 return (1); 564 } 565 } 566 return (0); 567} 568 569void 570checkmntlist(char *name, char **fromname, char **onname, char **type) 571{ 572 573 *fromname = getmntname(name, NULL, MNTFROM, type, NAME); 574 if (*fromname == NULL) { 575 *onname = getmntname(name, NULL, MNTON, type, NAME); 576 if (*onname != NULL) 577 *fromname = name; 578 } else 579 *onname = name; 580} 581 582size_t 583mntinfo(struct statfs **mntbuf) 584{ 585 static struct statfs *origbuf; 586 size_t bufsize; 587 int mntsize; 588 589 mntsize = getfsstat(NULL, 0l, MNT_NOWAIT); 590 if (mntsize <= 0) 591 return (0); 592 bufsize = (mntsize + 1) * sizeof(struct statfs); 593 if ((origbuf = malloc(bufsize)) == NULL) 594 err(1, "malloc"); 595 mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT); 596 *mntbuf = origbuf; 597 return (mntsize); 598} 599 600char * 601getrealname(char *name, char *realname) 602{ 603 char *dirname; 604 int havedir; 605 size_t baselen; 606 size_t dirlen; 607 608 dirname = '\0'; 609 havedir = 0; 610 if (*name == '/') { 611 if (ISDOT(name + 1) || ISDOTDOT(name + 1)) 612 strcpy(realname, "/"); 613 else { 614 if ((dirname = strrchr(name + 1, '/')) == NULL) 615 strncpy(realname, name, MAXPATHLEN); 616 else 617 havedir = 1; 618 } 619 } else { 620 if (ISDOT(name) || ISDOTDOT(name)) 621 (void)realpath(name, realname); 622 else { 623 if ((dirname = strrchr(name, '/')) == NULL) { 624 if ((realpath(name, realname)) == NULL) 625 return (NULL); 626 } else 627 havedir = 1; 628 } 629 } 630 if (havedir) { 631 *dirname++ = '\0'; 632 if (ISDOT(dirname)) { 633 *dirname = '\0'; 634 if ((realpath(name, realname)) == NULL) 635 return (NULL); 636 } else if (ISDOTDOT(dirname)) { 637 *--dirname = '/'; 638 if ((realpath(name, realname)) == NULL) 639 return (NULL); 640 } else { 641 if ((realpath(name, realname)) == NULL) 642 return (NULL); 643 baselen = strlen(realname); 644 dirlen = strlen(dirname); 645 if (baselen + dirlen + 1 > MAXPATHLEN) 646 return (NULL); 647 if (realname[1] == '\0') { 648 memmove(realname + 1, dirname, dirlen); 649 realname[dirlen + 1] = '\0'; 650 } else { 651 realname[baselen] = '/'; 652 memmove(realname + baselen + 1, 653 dirname, dirlen); 654 realname[baselen + dirlen + 1] = '\0'; 655 } 656 } 657 } 658 return (realname); 659} 660 661/* 662 * xdr routines for mount rpc's 663 */ 664int 665xdr_dir(XDR *xdrsp, char *dirp) 666{ 667 668 return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN)); 669} 670 671void 672usage() 673{ 674 675 (void)fprintf(stderr, "%s\n%s\n", 676 "usage: umount [-fv] special | node", 677 " umount -a | -A [-fv] [-h host] [-t type]"); 678 exit(1); 679} 680