umount.c revision 123161
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 123160 2003-12-05 09:22:40Z iedowse $"; 46#endif /* not lint */ 47 48#include <sys/param.h> 49#include <sys/mount.h> 50#include <sys/socket.h> 51#include <sys/stat.h> 52 53#include <netdb.h> 54#include <rpc/rpc.h> 55#include <nfs/rpcv2.h> 56 57#include <ctype.h> 58#include <err.h> 59#include <errno.h> 60#include <fstab.h> 61#include <stdio.h> 62#include <stdlib.h> 63#include <string.h> 64#include <unistd.h> 65 66#include "mounttab.h" 67 68typedef enum { FIND, REMOVE, CHECKUNIQUE } dowhat; 69 70struct addrinfo *nfshost_ai = NULL; 71int fflag, vflag; 72char *nfshost; 73 74struct statfs *checkmntlist(char *); 75int checkvfsname (const char *, char **); 76struct statfs *getmntentry(const char *fromname, const char *onname, 77 fsid_t *fsid, dowhat what); 78char **makevfslist (const char *); 79size_t mntinfo (struct statfs **); 80int namematch (struct addrinfo *); 81int parsehexfsid(const char *hex, fsid_t *fsid); 82int sacmp (struct sockaddr *, struct sockaddr *); 83int umountall (char **); 84int checkname (char *, char **); 85int umountfs(struct statfs *sfs); 86void usage (void); 87int xdr_dir (XDR *, char *); 88 89int 90main(int argc, char *argv[]) 91{ 92 int all, errs, ch, mntsize, error; 93 char **typelist = NULL; 94 struct statfs *mntbuf, *sfs; 95 struct addrinfo hints; 96 97 /* Start disks transferring immediately. */ 98 sync(); 99 100 all = errs = 0; 101 while ((ch = getopt(argc, argv, "AaF:fh:t:v")) != -1) 102 switch (ch) { 103 case 'A': 104 all = 2; 105 break; 106 case 'a': 107 all = 1; 108 break; 109 case 'F': 110 setfstab(optarg); 111 break; 112 case 'f': 113 fflag = MNT_FORCE; 114 break; 115 case 'h': /* -h implies -A. */ 116 all = 2; 117 nfshost = optarg; 118 break; 119 case 't': 120 if (typelist != NULL) 121 err(1, "only one -t option may be specified"); 122 typelist = makevfslist(optarg); 123 break; 124 case 'v': 125 vflag = 1; 126 break; 127 default: 128 usage(); 129 /* NOTREACHED */ 130 } 131 argc -= optind; 132 argv += optind; 133 134 if ((argc == 0 && !all) || (argc != 0 && all)) 135 usage(); 136 137 /* -h implies "-t nfs" if no -t flag. */ 138 if ((nfshost != NULL) && (typelist == NULL)) 139 typelist = makevfslist("nfs"); 140 141 if (nfshost != NULL) { 142 memset(&hints, 0, sizeof hints); 143 error = getaddrinfo(nfshost, NULL, &hints, &nfshost_ai); 144 if (error) 145 errx(1, "%s: %s", nfshost, gai_strerror(error)); 146 } 147 148 switch (all) { 149 case 2: 150 if ((mntsize = mntinfo(&mntbuf)) <= 0) 151 break; 152 /* 153 * We unmount the nfs-mounts in the reverse order 154 * that they were mounted. 155 */ 156 for (errs = 0, mntsize--; mntsize > 0; mntsize--) { 157 sfs = &mntbuf[mntsize]; 158 if (checkvfsname(sfs->f_fstypename, typelist)) 159 continue; 160 if (umountfs(sfs) != 0) 161 errs = 1; 162 } 163 free(mntbuf); 164 break; 165 case 1: 166 if (setfsent() == 0) 167 err(1, "%s", getfstab()); 168 errs = umountall(typelist); 169 break; 170 case 0: 171 for (errs = 0; *argv != NULL; ++argv) 172 if (checkname(*argv, typelist) != 0) 173 errs = 1; 174 break; 175 } 176 exit(errs); 177} 178 179int 180umountall(char **typelist) 181{ 182 struct xvfsconf vfc; 183 struct fstab *fs; 184 int rval; 185 char *cp; 186 static int firstcall = 1; 187 188 if ((fs = getfsent()) != NULL) 189 firstcall = 0; 190 else if (firstcall) 191 errx(1, "fstab reading failure"); 192 else 193 return (0); 194 do { 195 /* Ignore the root. */ 196 if (strcmp(fs->fs_file, "/") == 0) 197 continue; 198 /* 199 * !!! 200 * Historic practice: ignore unknown FSTAB_* fields. 201 */ 202 if (strcmp(fs->fs_type, FSTAB_RW) && 203 strcmp(fs->fs_type, FSTAB_RO) && 204 strcmp(fs->fs_type, FSTAB_RQ)) 205 continue; 206 /* Ignore unknown file system types. */ 207 if (getvfsbyname(fs->fs_vfstype, &vfc) == -1) 208 continue; 209 if (checkvfsname(fs->fs_vfstype, typelist)) 210 continue; 211 212 /* 213 * We want to unmount the file systems in the reverse order 214 * that they were mounted. So, we save off the file name 215 * in some allocated memory, and then call recursively. 216 */ 217 if ((cp = malloc((size_t)strlen(fs->fs_file) + 1)) == NULL) 218 err(1, "malloc failed"); 219 (void)strcpy(cp, fs->fs_file); 220 rval = umountall(typelist); 221 rval = checkname(cp, typelist) || rval; 222 free(cp); 223 return (rval); 224 } while ((fs = getfsent()) != NULL); 225 return (0); 226} 227 228/* 229 * Do magic checks on mountpoint/device/fsid, and then call unmount(2). 230 */ 231int 232checkname(char *name, char **typelist) 233{ 234 char buf[MAXPATHLEN]; 235 struct statfs sfsbuf; 236 struct stat sb; 237 struct statfs *sfs; 238 char *delimp; 239 dev_t dev; 240 int len; 241 242 /* 243 * 1. Check if the name exists in the mounttable. 244 */ 245 sfs = checkmntlist(name); 246 /* 247 * 2. Remove trailing slashes if there are any. After that 248 * we look up the name in the mounttable again. 249 */ 250 if (sfs == NULL) { 251 len = strlen(name); 252 while (len > 1 && name[len - 1] == '/') 253 name[--len] = '\0'; 254 sfs = checkmntlist(name); 255 } 256 /* 257 * 3. Check if the deprecated NFS syntax with an '@' has been used 258 * and translate it to the ':' syntax. Look up the name in the 259 * mount table again. 260 */ 261 if (sfs == NULL && (delimp = strrchr(name, '@')) != NULL) { 262 snprintf(buf, sizeof(buf), "%s:%.*s", delimp + 1, delimp - name, 263 name); 264 len = strlen(buf); 265 while (len > 1 && buf[len - 1] == '/') 266 buf[--len] = '\0'; 267 sfs = checkmntlist(buf); 268 } 269 /* 270 * 4. Resort to a statfs(2) call. This is the last check so that 271 * hung NFS filesystems for example can be unmounted without 272 * potentially blocking forever in statfs() as long as the 273 * filesystem is specified unambiguously. This covers all the 274 * hard cases such as symlinks and mismatches between the 275 * mount list and reality. 276 * We also do this if an ambiguous mount point was specified. 277 */ 278 if (sfs == NULL || (getmntentry(NULL, name, NULL, FIND) != NULL && 279 getmntentry(NULL, name, NULL, CHECKUNIQUE) == NULL)) { 280 if (statfs(name, &sfsbuf) != 0) { 281 warn("%s: statfs", name); 282 } else if (stat(name, &sb) != 0) { 283 warn("%s: stat", name); 284 } else if (S_ISDIR(sb.st_mode)) { 285 /* Check that `name' is the root directory. */ 286 dev = sb.st_dev; 287 snprintf(buf, sizeof(buf), "%s/..", name); 288 if (stat(buf, &sb) != 0) { 289 warn("%s: stat", buf); 290 } else if (sb.st_dev == dev) { 291 warnx("%s: not a file system root directory", 292 name); 293 return (1); 294 } else 295 sfs = &sfsbuf; 296 } 297 } 298 if (sfs == NULL) { 299 warnx("%s: unknown file system", name); 300 return (1); 301 } 302 if (checkvfsname(sfs->f_fstypename, typelist)) 303 return (1); 304 return (umountfs(sfs)); 305} 306 307/* 308 * NFS stuff and unmount(2) call 309 */ 310int 311umountfs(struct statfs *sfs) 312{ 313 char fsidbuf[64]; 314 enum clnt_stat clnt_stat; 315 struct timeval try; 316 struct addrinfo *ai, hints; 317 int do_rpc; 318 CLIENT *clp; 319 char *nfsdirname, *orignfsdirname; 320 char *hostp, *delimp; 321 322 ai = NULL; 323 do_rpc = 0; 324 hostp = NULL; 325 nfsdirname = delimp = orignfsdirname = NULL; 326 memset(&hints, 0, sizeof hints); 327 328 if (strcmp(sfs->f_fstypename, "nfs") == 0) { 329 if ((nfsdirname = strdup(sfs->f_mntfromname)) == NULL) 330 err(1, "strdup"); 331 orignfsdirname = nfsdirname; 332 if ((delimp = strrchr(nfsdirname, ':')) != NULL) { 333 *delimp = '\0'; 334 hostp = nfsdirname; 335 getaddrinfo(hostp, NULL, &hints, &ai); 336 if (ai == NULL) { 337 warnx("can't get net id for host"); 338 } 339 nfsdirname = delimp + 1; 340 } 341 342 /* 343 * Check if we have to start the rpc-call later. 344 * If there are still identical nfs-names mounted, 345 * we skip the rpc-call. Obviously this has to 346 * happen before unmount(2), but it should happen 347 * after the previous namecheck. 348 * A non-NULL return means that this is the last 349 * mount from mntfromname that is still mounted. 350 */ 351 if (getmntentry(sfs->f_mntfromname, NULL, NULL, 352 CHECKUNIQUE) != NULL) 353 do_rpc = 1; 354 } 355 356 if (!namematch(ai)) 357 return (1); 358 /* First try to unmount using the file system ID. */ 359 snprintf(fsidbuf, sizeof(fsidbuf), "FSID:%d:%d", sfs->f_fsid.val[0], 360 sfs->f_fsid.val[1]); 361 if (unmount(fsidbuf, fflag | MNT_BYFSID) != 0) { 362 /* XXX, non-root users get a zero fsid, so don't warn. */ 363 if (errno != ENOENT || sfs->f_fsid.val[0] != 0 || 364 sfs->f_fsid.val[1] != 0) 365 warn("unmount of %s failed", sfs->f_mntonname); 366 if (errno != ENOENT) 367 return (1); 368 /* Compatibility for old kernels. */ 369 if (sfs->f_fsid.val[0] != 0 || sfs->f_fsid.val[1] != 0) 370 warnx("retrying using path instead of file system ID"); 371 if (unmount(sfs->f_mntonname, fflag) != 0) { 372 warn("unmount of %s failed", sfs->f_mntonname); 373 return (1); 374 } 375 } 376 /* Mark this this file system as unmounted. */ 377 getmntentry(NULL, NULL, &sfs->f_fsid, REMOVE); 378 if (vflag) 379 (void)printf("%s: unmount from %s\n", sfs->f_mntfromname, 380 sfs->f_mntonname); 381 /* 382 * Report to mountd-server which nfsname 383 * has been unmounted. 384 */ 385 if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) { 386 clp = clnt_create(hostp, RPCPROG_MNT, RPCMNT_VER1, "udp"); 387 if (clp == NULL) { 388 warnx("%s: %s", hostp, 389 clnt_spcreateerror("RPCPROG_MNT")); 390 return (1); 391 } 392 clp->cl_auth = authsys_create_default(); 393 try.tv_sec = 20; 394 try.tv_usec = 0; 395 clnt_stat = clnt_call(clp, RPCMNT_UMOUNT, (xdrproc_t)xdr_dir, 396 nfsdirname, (xdrproc_t)xdr_void, (caddr_t)0, try); 397 if (clnt_stat != RPC_SUCCESS) { 398 warnx("%s: %s", hostp, 399 clnt_sperror(clp, "RPCMNT_UMOUNT")); 400 return (1); 401 } 402 /* 403 * Remove the unmounted entry from /var/db/mounttab. 404 */ 405 if (read_mtab()) { 406 clean_mtab(hostp, nfsdirname, vflag); 407 if(!write_mtab(vflag)) 408 warnx("cannot remove mounttab entry %s:%s", 409 hostp, nfsdirname); 410 free_mtab(); 411 } 412 free(orignfsdirname); 413 auth_destroy(clp->cl_auth); 414 clnt_destroy(clp); 415 } 416 return (0); 417} 418 419struct statfs * 420getmntentry(const char *fromname, const char *onname, fsid_t *fsid, dowhat what) 421{ 422 static struct statfs *mntbuf; 423 static size_t mntsize = 0; 424 static char *mntcheck = NULL; 425 struct statfs *sfs, *foundsfs; 426 int i, count; 427 428 if (mntsize <= 0) { 429 if ((mntsize = mntinfo(&mntbuf)) <= 0) 430 return (NULL); 431 } 432 if (mntcheck == NULL) { 433 if ((mntcheck = calloc(mntsize + 1, sizeof(int))) == NULL) 434 err(1, "calloc"); 435 } 436 /* 437 * We want to get the file systems in the reverse order 438 * that they were mounted. Unmounted file systems are marked 439 * in a table called 'mntcheck'. 440 */ 441 count = 0; 442 foundsfs = NULL; 443 for (i = mntsize - 1; i >= 0; i--) { 444 if (mntcheck[i]) 445 continue; 446 sfs = &mntbuf[i]; 447 if (fromname != NULL && strcmp(sfs->f_mntfromname, 448 fromname) != 0) 449 continue; 450 if (onname != NULL && strcmp(sfs->f_mntonname, onname) != 0) 451 continue; 452 if (fsid != NULL && bcmp(&sfs->f_fsid, fsid, 453 sizeof(*fsid)) != 0) 454 continue; 455 456 switch (what) { 457 case CHECKUNIQUE: 458 foundsfs = sfs; 459 count++; 460 continue; 461 case REMOVE: 462 mntcheck[i] = 1; 463 break; 464 default: 465 break; 466 } 467 return (sfs); 468 } 469 470 if (what == CHECKUNIQUE && count == 1) 471 return (foundsfs); 472 return (NULL); 473} 474 475int 476sacmp(struct sockaddr *sa1, struct sockaddr *sa2) 477{ 478 void *p1, *p2; 479 int len; 480 481 if (sa1->sa_family != sa2->sa_family) 482 return (1); 483 484 switch (sa1->sa_family) { 485 case AF_INET: 486 p1 = &((struct sockaddr_in *)sa1)->sin_addr; 487 p2 = &((struct sockaddr_in *)sa2)->sin_addr; 488 len = 4; 489 break; 490 case AF_INET6: 491 p1 = &((struct sockaddr_in6 *)sa1)->sin6_addr; 492 p2 = &((struct sockaddr_in6 *)sa2)->sin6_addr; 493 len = 16; 494 if (((struct sockaddr_in6 *)sa1)->sin6_scope_id != 495 ((struct sockaddr_in6 *)sa2)->sin6_scope_id) 496 return (1); 497 break; 498 default: 499 return (1); 500 } 501 502 return memcmp(p1, p2, len); 503} 504 505int 506namematch(struct addrinfo *ai) 507{ 508 struct addrinfo *aip; 509 510 if (nfshost == NULL || nfshost_ai == NULL) 511 return (1); 512 513 while (ai != NULL) { 514 aip = nfshost_ai; 515 while (aip != NULL) { 516 if (sacmp(ai->ai_addr, aip->ai_addr) == 0) 517 return (1); 518 aip = aip->ai_next; 519 } 520 ai = ai->ai_next; 521 } 522 523 return (0); 524} 525 526struct statfs * 527checkmntlist(char *name) 528{ 529 struct statfs *sfs; 530 fsid_t fsid; 531 532 sfs = NULL; 533 if (parsehexfsid(name, &fsid) == 0) 534 sfs = getmntentry(NULL, NULL, &fsid, FIND); 535 if (sfs == NULL) 536 sfs = getmntentry(NULL, name, NULL, FIND); 537 if (sfs == NULL) 538 sfs = getmntentry(name, NULL, NULL, FIND); 539 return (sfs); 540} 541 542size_t 543mntinfo(struct statfs **mntbuf) 544{ 545 static struct statfs *origbuf; 546 size_t bufsize; 547 int mntsize; 548 549 mntsize = getfsstat(NULL, 0, MNT_NOWAIT); 550 if (mntsize <= 0) 551 return (0); 552 bufsize = (mntsize + 1) * sizeof(struct statfs); 553 if ((origbuf = malloc(bufsize)) == NULL) 554 err(1, "malloc"); 555 mntsize = getfsstat(origbuf, (long)bufsize, MNT_NOWAIT); 556 *mntbuf = origbuf; 557 return (mntsize); 558} 559 560/* 561 * Convert a hexadecimal filesystem ID to an fsid_t. 562 * Returns 0 on success. 563 */ 564int 565parsehexfsid(const char *hex, fsid_t *fsid) 566{ 567 char hexbuf[3]; 568 int i; 569 570 if (strlen(hex) != sizeof(*fsid) * 2) 571 return (-1); 572 hexbuf[2] = '\0'; 573 for (i = 0; i < (int)sizeof(*fsid); i++) { 574 hexbuf[0] = hex[i * 2]; 575 hexbuf[1] = hex[i * 2 + 1]; 576 if (!isxdigit(hexbuf[0]) || !isxdigit(hexbuf[1])) 577 return (-1); 578 ((u_char *)fsid)[i] = strtol(hexbuf, NULL, 16); 579 } 580 return (0); 581} 582 583/* 584 * xdr routines for mount rpc's 585 */ 586int 587xdr_dir(XDR *xdrsp, char *dirp) 588{ 589 590 return (xdr_string(xdrsp, &dirp, RPCMNT_PATHLEN)); 591} 592 593void 594usage() 595{ 596 597 (void)fprintf(stderr, "%s\n%s\n", 598 "usage: umount [-fv] special | node", 599 " umount -a | -A [ -F fstab] [-fv] [-h host] [-t type]"); 600 exit(1); 601} 602