utils/exportfs/exportfs.c

   1 /*
   2  * utils/exportfs/exportfs.c
   3  *
   4  * Export file systems to knfsd
   5  *
   6  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
   7  *
   8  * Extensive changes, 1999, Neil Brown <neilb@cse.unsw.edu.au>
   9  */
  10
  11 #ifdef HAVE_CONFIG_H
  12 #include <config.h>
  13 #endif
  14
  15 #include <sys/types.h>
  16 #include <sys/stat.h>
  17 #include <sys/vfs.h>
  18 #include <sys/stat.h>
  19 #include <unistd.h>
  20 #include <stdbool.h>
  21 #include <stdlib.h>
  22 #include <string.h>
  23 #include <stdarg.h>
  24 #include <getopt.h>
  25 #include <fcntl.h>
  26 #include <netdb.h>
  27 #include <errno.h>
  28 #include <dirent.h>
  29
  30 #include "sockaddr.h"
  31 #include "misc.h"
  32 #include "nfslib.h"
  33 #include "exportfs.h"
  34 #include "xlog.h"
  35
  36 static void     export_all(int verbose);
  37 static void     exportfs(char *arg, char *options, int verbose);
  38 static void     unexportfs(char *arg, int verbose);
  39 static void     exports_update(int verbose);
  40 static void     dump(int verbose);
  41 static void     error(nfs_export *exp, int err);
  42 static void     usage(const char *progname);
  43 static void     validate_export(nfs_export *exp);
  44 static int      matchhostname(const char *hostname1, const char *hostname2);
  45 static void     export_d_read(const char *dname);
  46
  47 int
  48 main(int argc, char **argv)
  49 {
  50         char    *options = NULL;
  51         char    *progname = NULL;
  52         int     f_export = 1;
  53         int     f_all = 0;
  54         int     f_verbose = 0;
  55         int     f_reexport = 0;
  56         int     f_ignore = 0;
  57         int     i, c;
  58         int     new_cache = 0;
  59         int     force_flush = 0;
  60
  61         if ((progname = strrchr(argv[0], '/')) != NULL)
  62                 progname++;
  63         else
  64                 progname = argv[0];
  65
  66         xlog_open(progname);
  67         xlog_stderr(1);
  68         xlog_syslog(0);
  69
  70         export_errno = 0;
  71
  72         while ((c = getopt(argc, argv, "aio:ruvf")) != EOF) {
  73                 switch(c) {
  74                 case 'a':
  75                         f_all = 1;
  76                         break;
  77                 case 'i':
  78                         f_ignore = 1;
  79                         break;
  80                 case 'o':
  81                         options = optarg;
  82                         break;
  83                 case 'r':
  84                         f_reexport = 1;
  85                         f_all = 1;
  86                         break;
  87                 case 'u':
  88                         f_export = 0;
  89                         break;
  90                 case 'v':
  91                         f_verbose = 1;
  92                         break;
  93                 case 'f':
  94                         force_flush = 1;
  95                         break;
  96                 default:
  97                         usage(progname);
  98                         break;
  99                 }
 100         }
 101
 102         if (optind != argc && f_all) {
 103                 xlog(L_ERROR, "extra arguments are not permitted with -a or -r");
 104                 return 1;
 105         }
 106         if (f_ignore && (f_all || ! f_export)) {
 107                 xlog(L_ERROR, "-i not meaningful with -a, -r or -u");
 108                 return 1;
 109         }
 110         if (f_reexport && ! f_export) {
 111                 xlog(L_ERROR, "-r and -u are incompatible");
 112                 return 1;
 113         }
 114         new_cache = check_new_cache();
 115         if (optind == argc && ! f_all) {
 116                 if (force_flush) {
 117                         if (new_cache)
 118                                 cache_flush(1);
 119                         else {
 120                                 xlog(L_ERROR, "-f is available only "
 121                                         "with new cache controls. "
 122                                         "Mount /proc/fs/nfsd first");
 123                                 return 1;
 124                         }
 125                         return 0;
 126                 } else {
 127                         xtab_export_read();
 128                         dump(f_verbose);
 129                         return 0;
 130                 }
 131         }
 132         if (f_export && ! f_ignore) {
 133                 export_read(_PATH_EXPORTS);
 134                 export_d_read(_PATH_EXPORTS_D);
 135         }
 136         if (f_export) {
 137                 if (f_all)
 138                         export_all(f_verbose);
 139                 else
 140                         for (i = optind; i < argc ; i++)
 141                                 exportfs(argv[i], options, f_verbose);
 142         }
 143         /* If we are unexporting everything, then
 144          * don't care about what should be exported, as that
 145          * may require DNS lookups..
 146          */
 147         if (! ( !f_export && f_all)) {
 148                 /* note: xtab_*_read does not update entries if they already exist,
 149                  * so this will not lose new options
 150                  */
 151                 if (!f_reexport)
 152                         xtab_export_read();
 153                 if (!f_export)
 154                         for (i = optind ; i < argc ; i++)
 155                                 unexportfs(argv[i], f_verbose);
 156                 if (!new_cache)
 157                         rmtab_read();
 158         }
 159         if (!new_cache) {
 160                 xtab_mount_read();
 161                 exports_update(f_verbose);
 162         }
 163         xtab_export_write();
 164         if (new_cache)
 165                 cache_flush(force_flush);
 166         if (!new_cache)
 167                 xtab_mount_write();
 168
 169         return export_errno;
 170 }
 171
 172 static void
 173 exports_update_one(nfs_export *exp, int verbose)
 174 {
 175                 /* check mountpoint option */
 176         if (exp->m_mayexport &&
 177             exp->m_export.e_mountpoint &&
 178             !is_mountpoint(exp->m_export.e_mountpoint[0]?
 179                            exp->m_export.e_mountpoint:
 180                            exp->m_export.e_path)) {
 181                 printf("%s not exported as %s not a mountpoint.\n",
 182                        exp->m_export.e_path, exp->m_export.e_mountpoint);
 183                 exp->m_mayexport = 0;
 184         }
 185         if (exp->m_mayexport && ((exp->m_exported<1) || exp->m_changed)) {
 186                 if (verbose)
 187                         printf("%sexporting %s:%s to kernel\n",
 188                                exp->m_exported ?"re":"",
 189                                exp->m_client->m_hostname,
 190                                exp->m_export.e_path);
 191                 if (!export_export(exp))
 192                         error(exp, errno);
 193         }
 194         if (exp->m_exported && ! exp->m_mayexport) {
 195                 if (verbose)
 196                         printf("unexporting %s:%s from kernel\n",
 197                                exp->m_client->m_hostname,
 198                                exp->m_export.e_path);
 199                 if (!export_unexport(exp))
 200                         error(exp, errno);
 201         }
 202 }
 203
 204
 205 /* we synchronise intention with reality.
 206  * entries with m_mayexport get exported
 207  * entries with m_exported but not m_mayexport get unexported
 208  * looking at m_client->m_type == MCL_FQDN and m_client->m_type == MCL_GSS only
 209  */
 210 static void
 211 exports_update(int verbose)
 212 {
 213         nfs_export      *exp;
 214
 215         for (exp = exportlist[MCL_FQDN].p_head; exp; exp=exp->m_next) {
 216                 exports_update_one(exp, verbose);
 217         }
 218         for (exp = exportlist[MCL_GSS].p_head; exp; exp=exp->m_next) {
 219                 exports_update_one(exp, verbose);
 220         }
 221 }
 222
 223 /*
 224  * export_all finds all entries and
 225  *    marks them xtabent and mayexport so that they get exported
 226  */
 227 static void
 228 export_all(int verbose)
 229 {
 230         nfs_export      *exp;
 231         int             i;
 232
 233         for (i = 0; i < MCL_MAXTYPES; i++) {
 234                 for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
 235                         if (verbose)
 236                                 printf("exporting %s:%s\n",
 237                                        exp->m_client->m_hostname,
 238                                        exp->m_export.e_path);
 239                         exp->m_xtabent = 1;
 240                         exp->m_mayexport = 1;
 241                         exp->m_changed = 1;
 242                         exp->m_warned = 0;
 243                         validate_export(exp);
 244                 }
 245         }
 246 }
 247
 248
 249 static void
 250 exportfs(char *arg, char *options, int verbose)
 251 {
 252         struct exportent *eep;
 253         nfs_export      *exp = NULL;
 254         struct addrinfo *ai = NULL;
 255         char            *path;
 256         char            *hname = arg;
 257         int             htype;
 258
 259         if ((path = strchr(arg, ':')) != NULL)
 260                 *path++ = '\0';
 261
 262         if (!path || *path != '/') {
 263                 xlog(L_ERROR, "Invalid exporting option: %s", arg);
 264                 return;
 265         }
 266
 267         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 268                 ai = host_addrinfo(hname);
 269                 if (ai != NULL) {
 270                         exp = export_find(ai, path);
 271                         hname = ai->ai_canonname;
 272                 }
 273         } else
 274                 exp = export_lookup(hname, path, 0);
 275
 276         if (!exp) {
 277                 if (!(eep = mkexportent(hname, path, options)) ||
 278                     !(exp = export_create(eep, 0)))
 279                         goto out;
 280         } else if (!updateexportent(&exp->m_export, options))
 281                 goto out;
 282
 283         if (verbose)
 284                 printf("exporting %s:%s\n", exp->m_client->m_hostname,
 285                         exp->m_export.e_path);
 286         exp->m_xtabent = 1;
 287         exp->m_mayexport = 1;
 288         exp->m_changed = 1;
 289         exp->m_warned = 0;
 290         validate_export(exp);
 291
 292 out:
 293         freeaddrinfo(ai);
 294 }
 295
 296 static void
 297 unexportfs(char *arg, int verbose)
 298 {
 299         nfs_export      *exp;
 300         struct addrinfo *ai = NULL;
 301         char            *path;
 302         char            *hname = arg;
 303         int             htype;
 304
 305         if ((path = strchr(arg, ':')) != NULL)
 306                 *path++ = '\0';
 307
 308         if (!path || *path != '/') {
 309                 xlog(L_ERROR, "Invalid unexporting option: %s", arg);
 310                 return;
 311         }
 312
 313         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 314                 ai = host_addrinfo(hname);
 315                 if (ai)
 316                         hname = ai->ai_canonname;
 317         }
 318
 319         for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 320                 if (path && strcmp(path, exp->m_export.e_path))
 321                         continue;
 322                 if (htype != exp->m_client->m_type)
 323                         continue;
 324                 if (htype == MCL_FQDN
 325                     && !matchhostname(exp->m_export.e_hostname,
 326                                           hname))
 327                         continue;
 328                 if (htype != MCL_FQDN
 329                     && strcasecmp(exp->m_export.e_hostname, hname))
 330                         continue;
 331                 if (verbose) {
 332 #if 0
 333                         if (exp->m_exported) {
 334                                 printf("unexporting %s:%s from kernel\n",
 335                                        exp->m_client->m_hostname,
 336                                        exp->m_export.e_path);
 337                         }
 338                         else
 339 #endif
 340                                 printf("unexporting %s:%s\n",
 341                                         exp->m_client->m_hostname,
 342                                         exp->m_export.e_path);
 343                 }
 344 #if 0
 345                 if (exp->m_exported && !export_unexport(exp))
 346                         error(exp, errno);
 347 #endif
 348                 exp->m_xtabent = 0;
 349                 exp->m_mayexport = 0;
 350         }
 351
 352         freeaddrinfo(ai);
 353 }
 354
 355 static int can_test(void)
 356 {
 357         int fd;
 358         int n;
 359         char *setup = "nfsd 0.0.0.0 2147483647 -test-client-\n";
 360         fd = open("/proc/net/rpc/auth.unix.ip/channel", O_WRONLY);
 361         if ( fd < 0) return 0;
 362         n = write(fd, setup, strlen(setup));
 363         close(fd);
 364         if (n < 0)
 365                 return 0;
 366         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 367         if ( fd < 0) return 0;
 368         close(fd);
 369         return 1;
 370 }
 371
 372 static int test_export(char *path, int with_fsid)
 373 {
 374         char buf[1024];
 375         int fd, n;
 376
 377         sprintf(buf, "-test-client- %s 3 %d -1 -1 0\n",
 378                 path,
 379                 with_fsid ? NFSEXP_FSID : 0);
 380         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 381         if (fd < 0)
 382                 return 0;
 383         n = write(fd, buf, strlen(buf));
 384         close(fd);
 385         if (n < 0)
 386                 return 0;
 387         return 1;
 388 }
 389
 390 static void
 391 validate_export(nfs_export *exp)
 392 {
 393         /* Check that the given export point is potentially exportable.
 394          * We just give warnings here, don't cause anything to fail.
 395          * If a path doesn't exist, or is not a dir or file, give an warning
 396          * otherwise trial-export to '-test-client-' and check for failure.
 397          */
 398         struct stat stb;
 399         char *path = exp->m_export.e_path;
 400         struct statfs64 stf;
 401         int fs_has_fsid = 0;
 402
 403         if (stat(path, &stb) < 0) {
 404                 xlog(L_ERROR, "Failed to stat %s: %m", path);
 405                 return;
 406         }
 407         if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
 408                 xlog(L_ERROR, "%s is neither a directory nor a file. "
 409                         "Remote access will fail", path);
 410                 return;
 411         }
 412         if (!can_test())
 413                 return;
 414
 415         if (!statfs64(path, &stf) &&
 416             (stf.f_fsid.__val[0] || stf.f_fsid.__val[1]))
 417                 fs_has_fsid = 1;
 418
 419         if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
 420             fs_has_fsid) {
 421                 if ( !test_export(path, 1)) {
 422                         xlog(L_ERROR, "%s does not support NFS export", path);
 423                         return;
 424                 }
 425         } else if ( ! test_export(path, 0)) {
 426                 if (test_export(path, 1))
 427                         xlog(L_ERROR, "%s requires fsid= for NFS export", path);
 428                 else
 429                         xlog(L_ERROR, "%s does not support NFS export", path);
 430                 return;
 431
 432         }
 433 }
 434
 435 static _Bool
 436 is_hostname(const char *sp)
 437 {
 438         if (*sp == '\0' || *sp == '@')
 439                 return false;
 440
 441         for (; *sp != '\0'; sp++) {
 442                 if (*sp == '*' || *sp == '?' || *sp == '[' || *sp == '/')
 443                         return false;
 444                 if (*sp == '\\' && sp[1] != '\0')
 445                         sp++;
 446         }
 447
 448         return true;
 449 }
 450
 451 /*
 452  * Take care to perform an explicit reverse lookup on presentation
 453  * addresses.  Otherwise we don't get a real canonical name or a
 454  * complete list of addresses.
 455  */
 456 static struct addrinfo *
 457 address_list(const char *hostname)
 458 {
 459         struct addrinfo *ai;
 460         char *cname;
 461
 462         ai = host_pton(hostname);
 463         if (ai != NULL) {
 464                 /* @hostname was a presentation address */
 465                 cname = host_canonname(ai->ai_addr);
 466                 freeaddrinfo(ai);
 467                 if (cname != NULL)
 468                         goto out;
 469         }
 470         /* @hostname was a hostname or had no reverse mapping */
 471         cname = strdup(hostname);
 472         if (cname == NULL)
 473                 return NULL;
 474
 475 out:
 476         ai = host_addrinfo(cname);
 477         free(cname);
 478         return ai;
 479 }
 480
 481 static int
 482 matchhostname(const char *hostname1, const char *hostname2)
 483 {
 484         struct addrinfo *results1 = NULL, *results2 = NULL;
 485         struct addrinfo *ai1, *ai2;
 486         int result = 0;
 487
 488         if (strcasecmp(hostname1, hostname2) == 0)
 489                 return 1;
 490
 491         /*
 492          * Don't pass export wildcards or netgroup names to DNS
 493          */
 494         if (!is_hostname(hostname1) || !is_hostname(hostname2))
 495                 return 0;
 496
 497         results1 = address_list(hostname1);
 498         if (results1 == NULL)
 499                 goto out;
 500         results2 = address_list(hostname2);
 501         if (results2 == NULL)
 502                 goto out;
 503
 504         if (strcasecmp(results1->ai_canonname, results2->ai_canonname) == 0) {
 505                 result = 1;
 506                 goto out;
 507         }
 508
 509         for (ai1 = results1; ai1 != NULL; ai1 = ai1->ai_next)
 510                 for (ai2 = results2; ai2 != NULL; ai2 = ai2->ai_next)
 511                         if (nfs_compare_sockaddr(ai1->ai_addr, ai2->ai_addr)) {
 512                                 result = 1;
 513                                 break;
 514                         }
 515
 516 out:
 517         freeaddrinfo(results1);
 518         freeaddrinfo(results2);
 519         return result;
 520 }
 521
 522 /* Based on mnt_table_parse_dir() in
 523    util-linux-ng/shlibs/mount/src/tab_parse.c */
 524 static void
 525 export_d_read(const char *dname)
 526 {
 527         int n = 0, i;
 528         struct dirent **namelist = NULL;
 529
 530
 531         n = scandir(dname, &namelist, NULL, versionsort);
 532         if (n < 0)
 533                 xlog(L_NOTICE, "scandir %s: %s", dname, strerror(errno));
 534         else if (n == 0)
 535                 return;
 536
 537         for (i = 0; i < n; i++) {
 538                 struct dirent *d = namelist[i];
 539                 size_t namesz;
 540                 char fname[PATH_MAX + 1];
 541                 int fname_len;
 542
 543
 544                 if (d->d_type != DT_UNKNOWN
 545                     && d->d_type != DT_REG
 546                     && d->d_type != DT_LNK)
 547                         continue;
 548                 if (*d->d_name == '.')
 549                         continue;
 550
 551 #define _EXT_EXPORT_SIZ   (sizeof(_EXT_EXPORT) - 1)
 552                 namesz = strlen(d->d_name);
 553                 if (!namesz
 554                     || namesz < _EXT_EXPORT_SIZ + 1
 555                     || strcmp(d->d_name + (namesz - _EXT_EXPORT_SIZ),
 556                               _EXT_EXPORT))
 557                         continue;
 558
 559                 fname_len = snprintf(fname, PATH_MAX +1, "%s/%s", dname, d->d_name);
 560                 if (fname_len > PATH_MAX) {
 561                         xlog(L_WARNING, "Too long file name: %s in %s", d->d_name, dname);
 562                         continue;
 563                 }
 564
 565                 export_read(fname);
 566         }
 567
 568         for (i = 0; i < n; i++)
 569                 free(namelist[i]);
 570         free(namelist);
 571
 572         return;
 573 }
 574
 575 static char
 576 dumpopt(char c, char *fmt, ...)
 577 {
 578         va_list ap;
 579
 580         va_start(ap, fmt);
 581         printf("%c", c);
 582         vprintf(fmt, ap);
 583         va_end(ap);
 584         return ',';
 585 }
 586
 587 static void
 588 dump(int verbose)
 589 {
 590         nfs_export      *exp;
 591         struct exportent *ep;
 592         int             htype;
 593         char            *hname, c;
 594
 595         for (htype = 0; htype < MCL_MAXTYPES; htype++) {
 596                 for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 597                         ep = &exp->m_export;
 598                         if (!exp->m_xtabent)
 599                             continue; /* neilb */
 600                         if (htype == MCL_ANONYMOUS)
 601                                 hname = "<world>";
 602                         else
 603                                 hname = ep->e_hostname;
 604                         if (strlen(ep->e_path) > 14)
 605                                 printf("%-14s\n\t\t%s", ep->e_path, hname);
 606                         else
 607                                 printf("%-14s\t%s", ep->e_path, hname);
 608                         if (!verbose) {
 609                                 printf("\n");
 610                                 continue;
 611                         }
 612                         c = '(';
 613                         if (ep->e_flags & NFSEXP_READONLY)
 614                                 c = dumpopt(c, "ro");
 615                         else
 616                                 c = dumpopt(c, "rw");
 617                         if (ep->e_flags & NFSEXP_ASYNC)
 618                                 c = dumpopt(c, "async");
 619                         if (ep->e_flags & NFSEXP_GATHERED_WRITES)
 620                                 c = dumpopt(c, "wdelay");
 621                         if (ep->e_flags & NFSEXP_NOHIDE)
 622                                 c = dumpopt(c, "nohide");
 623                         if (ep->e_flags & NFSEXP_CROSSMOUNT)
 624                                 c = dumpopt(c, "crossmnt");
 625                         if (ep->e_flags & NFSEXP_INSECURE_PORT)
 626                                 c = dumpopt(c, "insecure");
 627                         if (ep->e_flags & NFSEXP_ROOTSQUASH)
 628                                 c = dumpopt(c, "root_squash");
 629                         else
 630                                 c = dumpopt(c, "no_root_squash");
 631                         if (ep->e_flags & NFSEXP_ALLSQUASH)
 632                                 c = dumpopt(c, "all_squash");
 633                         if (ep->e_flags & NFSEXP_NOSUBTREECHECK)
 634                                 c = dumpopt(c, "no_subtree_check");
 635                         if (ep->e_flags & NFSEXP_NOAUTHNLM)
 636                                 c = dumpopt(c, "insecure_locks");
 637                         if (ep->e_flags & NFSEXP_NOACL)
 638                                 c = dumpopt(c, "no_acl");
 639                         if (ep->e_flags & NFSEXP_FSID)
 640                                 c = dumpopt(c, "fsid=%d", ep->e_fsid);
 641                         if (ep->e_uuid)
 642                                 c = dumpopt(c, "fsid=%s", ep->e_uuid);
 643                         if (ep->e_mountpoint)
 644                                 c = dumpopt(c, "mountpoint%s%s",
 645                                             ep->e_mountpoint[0]?"=":"",
 646                                             ep->e_mountpoint);
 647                         if (ep->e_anonuid != 65534)
 648                                 c = dumpopt(c, "anonuid=%d", ep->e_anonuid);
 649                         if (ep->e_anongid != 65534)
 650                                 c = dumpopt(c, "anongid=%d", ep->e_anongid);
 651                         switch(ep->e_fslocmethod) {
 652                         case FSLOC_NONE:
 653                                 break;
 654                         case FSLOC_REFER:
 655                                 c = dumpopt(c, "refer=%s", ep->e_fslocdata);
 656                                 break;
 657                         case FSLOC_REPLICA:
 658                                 c = dumpopt(c, "replicas=%s", ep->e_fslocdata);
 659                                 break;
 660 #ifdef DEBUG
 661                         case FSLOC_STUB:
 662                                 c = dumpopt(c, "fsloc=stub");
 663                                 break;
 664 #endif
 665                         }
 666                         secinfo_show(stdout, ep);
 667                         printf("%c\n", (c != '(')? ')' : ' ');
 668                 }
 669         }
 670 }
 671
 672 static void
 673 error(nfs_export *exp, int err)
 674 {
 675         xlog(L_ERROR, "%s:%s: %s", exp->m_client->m_hostname,
 676                 exp->m_export.e_path, strerror(err));
 677 }
 678
 679 static void
 680 usage(const char *progname)
 681 {
 682         fprintf(stderr, "usage: %s [-aruv] [host:/path]\n", progname);
 683         exit(1);
 684 }