umount.c revision 117794
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 117794 2003-07-20 00:11:27Z 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 > 0 && 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 > 0 && 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 warn("unmount of %s failed", sfs->f_mntonname); 363 if (errno != ENOENT) 364 return (1); 365 /* Compatability for old kernels. */ 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 hexidecimal 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 < 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", 595 " umount -a | -A [ -F fstab] [-fv] [-h host] [-t type]"); 596 exit(1); 597} 598