umount.c revision 141611
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 * 4. 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 30#ifndef lint 31static const char copyright[] = 32"@(#) Copyright (c) 1980, 1989, 1993\n\ 33 The Regents of the University of California. All rights reserved.\n"; 34#endif /* not lint */ 35 36#ifndef lint 37#if 0 38static char sccsid[] = "@(#)umount.c 8.8 (Berkeley) 5/8/95"; 39#endif 40static const char rcsid[] = 41 "$FreeBSD: head/sbin/umount/umount.c 141611 2005-02-10 09:19:34Z ru $"; 42#endif /* not lint */ 43 44#include <sys/param.h> 45#include <sys/mount.h> 46#include <sys/socket.h> 47#include <sys/stat.h> 48 49#include <netdb.h> 50#include <rpc/rpc.h> 51#include <nfs/rpcv2.h> 52 53#include <ctype.h> 54#include <err.h> 55#include <errno.h> 56#include <fstab.h> 57#include <stdio.h> 58#include <stdlib.h> 59#include <string.h> 60#include <unistd.h> 61 62#include "mounttab.h" 63 64typedef enum { FIND, REMOVE, CHECKUNIQUE } dowhat; 65 66struct addrinfo *nfshost_ai = NULL; 67int fflag, vflag; 68char *nfshost; 69 70struct statfs *checkmntlist(char *); 71int checkvfsname (const char *, char **); 72struct statfs *getmntentry(const char *fromname, const char *onname, 73 fsid_t *fsid, dowhat what); 74char **makevfslist (const char *); 75size_t mntinfo (struct statfs **); 76int namematch (struct addrinfo *); 77int parsehexfsid(const char *hex, fsid_t *fsid); 78int sacmp (struct sockaddr *, struct sockaddr *); 79int umountall (char **); 80int checkname (char *, char **); 81int umountfs(struct statfs *sfs); 82void usage (void); 83int xdr_dir (XDR *, char *); 84 85int 86main(int argc, char *argv[]) 87{ 88 int all, errs, ch, mntsize, error; 89 char **typelist = NULL; 90 struct statfs *mntbuf, *sfs; 91 struct addrinfo hints; 92 93 /* Start disks transferring immediately. */ 94 sync(); 95 96 all = errs = 0; 97 while ((ch = getopt(argc, argv, "AaF:fh: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 setfstab(optarg); 107 break; 108 case 'f': 109 fflag = MNT_FORCE; 110 break; 111 case 'h': /* -h implies -A. */ 112 all = 2; 113 nfshost = optarg; 114 break; 115 case 't': 116 if (typelist != NULL) 117 err(1, "only one -t option may be specified"); 118 typelist = makevfslist(optarg); 119 break; 120 case 'v': 121 vflag = 1; 122 break; 123 default: 124 usage(); 125 /* NOTREACHED */ 126 } 127 argc -= optind; 128 argv += optind; 129 130 if ((argc == 0 && !all) || (argc != 0 && all)) 131 usage(); 132 133 /* -h implies "-t nfs" if no -t flag. */ 134 if ((nfshost != NULL) && (typelist == NULL)) 135 typelist = makevfslist("nfs"); 136 137 if (nfshost != NULL) { 138 memset(&hints, 0, sizeof hints); 139 error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai); 140 if (error) 141 errx(1, "%s: %s", nfshost, gai_strerror(error)); 142 } 143 144 switch (all) { 145 case 2: 146 if ((mntsize = mntinfo(&mntbuf)) <= 0) 147 break; 148 /* 149 * We unmount the nfs-mounts in the reverse order 150 * that they were mounted. 151 */ 152 for (errs = 0, mntsize--; mntsize > 0; mntsize--) { 153 sfs = &mntbuf[mntsize]; 154 if (checkvfsname(sfs->f_fstypename, typelist)) 155 continue; 156 if (umountfs(sfs) != 0) 157 errs = 1; 158 } 159 free(mntbuf); 160 break; 161 case 1: 162 if (setfsent() == 0) 163 err(1, "%s", getfstab()); 164 errs = umountall(typelist); 165 break; 166 case 0: 167 for (errs = 0; *argv != NULL; ++argv) 168 if (checkname(*argv, typelist) != 0) 169 errs = 1; 170 break; 171 } 172 exit(errs); 173} 174 175int 176umountall(char **typelist) 177{ 178 struct xvfsconf vfc; 179 struct fstab *fs; 180 int rval; 181 char *cp; 182 static int firstcall = 1; 183 184 if ((fs = getfsent()) != NULL) 185 firstcall = 0; 186 else if (firstcall) 187 errx(1, "fstab reading failure"); 188 else 189 return (0); 190 do { 191 /* Ignore the root. */ 192 if (strcmp(fs->fs_file, "/") == 0) 193 continue; 194 /* 195 * !!! 196 * Historic practice: ignore unknown FSTAB_* fields. 197 */ 198 if (strcmp(fs->fs_type, FSTAB_RW) && 199 strcmp(fs->fs_type, FSTAB_RO) && 200 strcmp(fs->fs_type, FSTAB_RQ)) 201 continue; 202 /* Ignore unknown file system types. */ 203 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1) 204 continue; 205 if (checkvfsname(fs->fs_vfstype, typelist)) 206 continue; 207 208 /* 209 * We want to unmount the file systems in the reverse order 210 * that they were mounted. So, we save off the file name 211 * in some allocated memory, and then call recursively. 212 */ 213 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL) 214 err(1, "malloc failed"); 215 (void)strcpy(cp, fs->fs_file); 216 rval = umountall(typelist); 217 rval = checkname(cp, typelist) || rval; 218 free(cp); 219 return (rval); 220 } while ((fs = getfsent()) != NULL); 221 return (0); 222} 223 224/* 225 * Do magic checks on mountpoint/device/fsid, and then call unmount(2). 226 */ 227int 228checkname(char *name, char **typelist) 229{ 230 char buf[MAXPATHLEN]; 231 struct statfs sfsbuf; 232 struct stat sb; 233 struct statfs *sfs; 234 char *delimp; 235 dev_t dev; 236 int len; 237 238 /* 239 * 1. Check if the name exists in the mounttable. 240 */ 241 sfs = checkmntlist(name); 242 /* 243 * 2. Remove trailing slashes if there are any. After that 244 * we look up the name in the mounttable again. 245 */ 246 if (sfs == NULL) { 247 len = strlen(name); 248 while (len > 1 && name[len - 1] == '/') 249 name[--len] = '\0'; 250 sfs = checkmntlist(name); 251 } 252 /* 253 * 3. Check if the deprecated NFS syntax with an '@' has been used 254 * and translate it to the ':' syntax. Look up the name in the 255 * mount table again. 256 */ 257 if (sfs == NULL && (delimp = strrchr(name, '@')) != NULL) { 258 snprintf(buf, sizeof(buf), "%s:%.*s", delimp + 1, delimp - name, 259 name); 260 len = strlen(buf); 261 while (len > 1 && buf[len - 1] == '/') 262 buf[--len] = '\0'; 263 sfs = checkmntlist(buf); 264 } 265 /* 266 * 4. Resort to a statfs(2) call. This is the last check so that 267 * hung NFS filesystems for example can be unmounted without 268 * potentially blocking forever in statfs() as long as the 269 * filesystem is specified unambiguously. This covers all the 270 * hard cases such as symlinks and mismatches between the 271 * mount list and reality. 272 * We also do this if an ambiguous mount point was specified. 273 */ 274 if (sfs == NULL || (getmntentry(NULL, name, NULL, FIND) != NULL && 275 getmntentry(NULL, name, NULL, CHECKUNIQUE) == NULL)) { 276 if (statfs(name, &sfsbuf) != 0) { 277 warn("%s: statfs", name); 278 } else if (stat(name, &sb) != 0) { 279 warn("%s: stat", name); 280 } else if (S_ISDIR(sb.st_mode)) { 281 /* Check that `name' is the root directory. */ 282 dev = sb.st_dev; 283 snprintf(buf, sizeof(buf), "%s/..", name); 284 if (stat(buf, &sb) != 0) { 285 warn("%s: stat", buf); 286 } else if (sb.st_dev == dev) { 287 warnx("%s: not a file system root directory", 288 name); 289 return (1); 290 } else 291 sfs = &sfsbuf; 292 } 293 } 294 if (sfs == NULL) { 295 warnx("%s: unknown file system", name); 296 return (1); 297 } 298 if (checkvfsname(sfs->f_fstypename, typelist)) 299 return (1); 300 return (umountfs(sfs)); 301} 302 303/* 304 * NFS stuff and unmount(2) call 305 */ 306int 307umountfs(struct statfs *sfs) 308{ 309 char fsidbuf[64]; 310 enum clnt_stat clnt_stat; 311 struct timeval try; 312 struct addrinfo *ai, hints; 313 int do_rpc; 314 CLIENT *clp; 315 char *nfsdirname, *orignfsdirname; 316 char *hostp, *delimp; 317 318 ai = NULL; 319 do_rpc = 0; 320 hostp = NULL; 321 nfsdirname = delimp = orignfsdirname = NULL; 322 memset(&hints, 0, sizeof hints); 323 324 if (strcmp(sfs->f_fstypename, "nfs") == 0) { 325 if ((nfsdirname = strdup(sfs->f_mntfromname)) == NULL) 326 err(1, "strdup"); 327 orignfsdirname = nfsdirname; 328 if ((delimp = strrchr(nfsdirname, ':')) != NULL) { 329 *delimp = '\0'; 330 hostp = nfsdirname; 331 getaddrinfo(hostp, NULL, &hints, &ai); 332 if (ai == NULL) { 333 warnx("can't get net id for host"); 334 } 335 nfsdirname = delimp + 1; 336 } 337 338 /* 339 * Check if we have to start the rpc-call later. 340 * If there are still identical nfs-names mounted, 341 * we skip the rpc-call. Obviously this has to 342 * happen before unmount(2), but it should happen 343 * after the previous namecheck. 344 * A non-NULL return means that this is the last 345 * mount from mntfromname that is still mounted. 346 */ 347 if (getmntentry(sfs->f_mntfromname, NULL, NULL, 348 CHECKUNIQUE) != NULL) 349 do_rpc = 1; 350 } 351 352 if (!namematch(ai)) 353 return (1); 354 /* First try to unmount using the file system ID. */ 355 snprintf(fsidbuf, sizeof(fsidbuf), "FSID:%d:%d", sfs->f_fsid.val[0], 356 sfs->f_fsid.val[1]); 357 if (unmount(fsidbuf, fflag | MNT_BYFSID) != 0) { 358 /* XXX, non-root users get a zero fsid, so don't warn. */ 359 if (errno != ENOENT || sfs->f_fsid.val[0] != 0 || 360 sfs->f_fsid.val[1] != 0) 361 warn("unmount of %s failed", sfs->f_mntonname); 362 if (errno != ENOENT) 363 return (1); 364 /* Compatibility for old kernels. */ 365 if (sfs->f_fsid.val[0] != 0 || sfs->f_fsid.val[1] != 0) 366 warnx("retrying using path instead of file system ID"); 367 if (unmount(sfs->f_mntonname, fflag) != 0) { 368 warn("unmount of %s failed", sfs->f_mntonname); 369 return (1); 370 } 371 } 372 /* Mark this this file system as unmounted. */ 373 getmntentry(NULL, NULL, &sfs->f_fsid, REMOVE); 374 if (vflag) 375 (void)printf("%s: unmount from %s\n", sfs->f_mntfromname, 376 sfs->f_mntonname); 377 /* 378 * Report to mountd-server which nfsname 379 * has been unmounted. 380 */ 381 if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) { 382 clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, "udp"); 383 if (clp == NULL) { 384 warnx("%s: %s", hostp, 385 clnt_spcreateerror("RPCPROG_MNT")); 386 return (1); 387 } 388 clp->cl_auth = authsys_create_default(); 389 try.tv_sec = 20; 390 try.tv_usec = 0; 391 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, (xdrproc_t)xdr_dir, 392 nfsdirname, (xdrproc_t)xdr_void, (caddr_t)0, try); 393 if (clnt_stat != RPC_SUCCESS) { 394 warnx("%s: %s", hostp, 395 clnt_sperror(clp, "RPCMNT_UMOUNT")); 396 return (1); 397 } 398 /* 399 * Remove the unmounted entry from /var/db/mounttab. 400 */ 401 if (read_mtab()) { 402 clean_mtab(hostp, nfsdirname, vflag); 403 if(!write_mtab(vflag)) 404 warnx("cannot remove mounttab entry %s:%s", 405 hostp, nfsdirname); 406 free_mtab(); 407 } 408 free(orignfsdirname); 409 auth_destroy(clp->cl_auth); 410 clnt_destroy(clp); 411 } 412 return (0); 413} 414 415struct statfs * 416getmntentry(const char *fromname, const char *onname, fsid_t *fsid, dowhat what) 417{ 418 static struct statfs *mntbuf; 419 static size_t mntsize = 0; 420 static char *mntcheck = NULL; 421 struct statfs *sfs, *foundsfs; 422 int i, count; 423 424 if (mntsize <= 0) { 425 if ((mntsize = mntinfo(&mntbuf)) <= 0) 426 return (NULL); 427 } 428 if (mntcheck == NULL) { 429 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL) 430 err(1, "calloc"); 431 } 432 /* 433 * We want to get the file systems in the reverse order 434 * that they were mounted. Unmounted file systems are marked 435 * in a table called 'mntcheck'. 436 */ 437 count = 0; 438 foundsfs = NULL; 439 for (i = mntsize - 1; i >= 0; i--) { 440 if (mntcheck[i]) 441 continue; 442 sfs = &mntbuf[i]; 443 if (fromname != NULL && strcmp(sfs->f_mntfromname, 444 fromname) != 0) 445 continue; 446 if (onname != NULL && strcmp(sfs->f_mntonname, onname) != 0) 447 continue; 448 if (fsid != NULL && bcmp(&sfs->f_fsid, fsid, 449 sizeof(*fsid)) != 0) 450 continue; 451 452 switch (what) { 453 case CHECKUNIQUE: 454 foundsfs = sfs; 455 count++; 456 continue; 457 case REMOVE: 458 mntcheck[i] = 1; 459 break; 460 default: 461 break; 462 } 463 return (sfs); 464 } 465 466 if (what == CHECKUNIQUE && count == 1) 467 return (foundsfs); 468 return (NULL); 469} 470 471int 472sacmp(struct sockaddr *sa1, struct sockaddr *sa2) 473{ 474 void *p1, *p2; 475 int len; 476 477 if (sa1->sa_family != sa2->sa_family) 478 return (1); 479 480 switch (sa1->sa_family) { 481 case AF_INET: 482 p1 = &((struct sockaddr_in *)sa1)->sin_addr; 483 p2 = &((struct sockaddr_in *)sa2)->sin_addr; 484 len = 4; 485 break; 486 case AF_INET6: 487 p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr; 488 p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr; 489 len = 16; 490 if (((struct sockaddr_in6 *)sa1)->sin6_scope_id != 491 ((struct sockaddr_in6 *)sa2)->sin6_scope_id) 492 return (1); 493 break; 494 default: 495 return (1); 496 } 497 498 return memcmp(p1, p2, len); 499} 500 501int 502namematch(struct addrinfo *ai) 503{ 504 struct addrinfo *aip; 505 506 if (nfshost == NULL || nfshost_ai == NULL) 507 return (1); 508 509 while (ai != NULL) { 510 aip = nfshost_ai; 511 while (aip != NULL) { 512 if (sacmp(ai->ai_addr, aip->ai_addr) == 0) 513 return (1); 514 aip = aip->ai_next; 515 } 516 ai = ai->ai_next; 517 } 518 519 return (0); 520} 521 522struct statfs * 523checkmntlist(char *name) 524{ 525 struct statfs *sfs; 526 fsid_t fsid; 527 528 sfs = NULL; 529 if (parsehexfsid(name, &fsid) == 0) 530 sfs = getmntentry(NULL, NULL, &fsid, FIND); 531 if (sfs == NULL) 532 sfs = getmntentry(NULL, name, NULL, FIND); 533 if (sfs == NULL) 534 sfs = getmntentry(name, NULL, NULL, FIND); 535 return (sfs); 536} 537 538size_t 539mntinfo(struct statfs **mntbuf) 540{ 541 static struct statfs *origbuf; 542 size_t bufsize; 543 int mntsize; 544 545 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 546 if (mntsize <= 0) 547 return (0); 548 bufsize = (mntsize + 1) * sizeof(struct statfs); 549 if ((origbuf = malloc(bufsize)) == NULL) 550 err(1, "malloc"); 551 mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT); 552 *mntbuf = origbuf; 553 return (mntsize); 554} 555 556/* 557 * Convert a hexadecimal filesystem ID to an fsid_t. 558 * Returns 0 on success. 559 */ 560int 561parsehexfsid(const char *hex, fsid_t *fsid) 562{ 563 char hexbuf[3]; 564 int i; 565 566 if (strlen(hex) != sizeof(*fsid) * 2) 567 return (-1); 568 hexbuf[2] = '\0'; 569 for (i = 0; i < (int)sizeof(*fsid); i++) { 570 hexbuf[0] = hex[i * 2]; 571 hexbuf[1] = hex[i * 2 + 1]; 572 if (!isxdigit(hexbuf[0]) || !isxdigit(hexbuf[1])) 573 return (-1); 574 ((u_char *)fsid)[i] = strtol(hexbuf, NULL, 16); 575 } 576 return (0); 577} 578 579/* 580 * xdr routines for mount rpc's 581 */ 582int 583xdr_dir(XDR *xdrsp, char *dirp) 584{ 585 586 return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN)); 587} 588 589void 590usage() 591{ 592 593 (void)fprintf(stderr, "%s\n%s\n", 594 "usage: umount [-fv] special | node | fsid", 595 " umount -a | -A [-F fstab] [-fv] [-h host] [-t type]"); 596 exit(1); 597} 598