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/vfs.h>
  16 #include <sys/stat.h>
  17 #include <unistd.h>
  18 #include <stdbool.h>
  19 #include <stdlib.h>
  20 #include <string.h>
  21 #include <stdarg.h>
  22 #include <getopt.h>
  23 #include <netdb.h>
  24 #include <errno.h>
  25 #include "xmalloc.h"
  26 #include "misc.h"
  27 #include "nfslib.h"
  28 #include "exportfs.h"
  29 #include "xmalloc.h"
  30 #include "xlog.h"
  31
  32 static void     export_all(int verbose);
  33 static void     exportfs(char *arg, char *options, int verbose);
  34 static void     unexportfs(char *arg, int verbose);
  35 static void     exports_update(int verbose);
  36 static void     dump(int verbose);
  37 static void     error(nfs_export *exp, int err);
  38 static void     usage(void);
  39 static void     validate_export(nfs_export *exp);
  40 static int      matchhostname(const char *hostname1, const char *hostname2);
  41
  42 int
  43 main(int argc, char **argv)
  44 {
  45         char    *options = NULL;
  46         int     f_export = 1;
  47         int     f_all = 0;
  48         int     f_verbose = 0;
  49         int     f_reexport = 0;
  50         int     f_ignore = 0;
  51         int     i, c;
  52         int     new_cache = 0;
  53         int     force_flush = 0;
  54
  55         xlog_open("exportfs");
  56
  57         export_errno = 0;
  58
  59         while ((c = getopt(argc, argv, "aio:ruvf")) != EOF) {
  60                 switch(c) {
  61                 case 'a':
  62                         f_all = 1;
  63                         break;
  64                 case 'i':
  65                         f_ignore = 1;
  66                         break;
  67                 case 'o':
  68                         options = optarg;
  69                         break;
  70                 case 'r':
  71                         f_reexport = 1;
  72                         f_all = 1;
  73                         break;
  74                 case 'u':
  75                         f_export = 0;
  76                         break;
  77                 case 'v':
  78                         f_verbose = 1;
  79                         break;
  80                 case 'f':
  81                         force_flush = 1;
  82                         break;
  83                 default:
  84                         usage();
  85                         break;
  86                 }
  87         }
  88
  89         if (optind != argc && f_all) {
  90                 fprintf(stderr,"exportfs: extra arguments are not permitted with -a or -r.\n");
  91                 return 1;
  92         }
  93         if (f_ignore && (f_all || ! f_export)) {
  94                 fprintf(stderr,"exportfs: -i not meaningful with -a, -r or -u.\n");
  95                 return 1;
  96         }
  97         if (f_reexport && ! f_export) {
  98                 fprintf(stderr, "exportfs: -r and -u are incompatible.\n");
  99                 return 1;
 100         }
 101         new_cache = check_new_cache();
 102         if (optind == argc && ! f_all) {
 103                 if (force_flush) {
 104                         if (new_cache)
 105                                 cache_flush(1);
 106                         else {
 107                                 fprintf(stderr, "exportfs: -f: only available with new cache controls: mount /proc/fs/nfsd first\n");
 108                                 exit(1);
 109                         }
 110                         return 0;
 111                 } else {
 112                         xtab_export_read();
 113                         dump(f_verbose);
 114                         return 0;
 115                 }
 116         }
 117         if (f_export && ! f_ignore)
 118                 export_read(_PATH_EXPORTS);
 119         if (f_export) {
 120                 if (f_all)
 121                         export_all(f_verbose);
 122                 else
 123                         for (i = optind; i < argc ; i++)
 124                                 exportfs(argv[i], options, f_verbose);
 125         }
 126         /* If we are unexporting everything, then
 127          * don't care about what should be exported, as that
 128          * may require DNS lookups..
 129          */
 130         if (! ( !f_export && f_all)) {
 131                 /* note: xtab_*_read does not update entries if they already exist,
 132                  * so this will not lose new options
 133                  */
 134                 if (!f_reexport)
 135                         xtab_export_read();
 136                 if (!f_export)
 137                         for (i = optind ; i < argc ; i++)
 138                                 unexportfs(argv[i], f_verbose);
 139                 if (!new_cache)
 140                         rmtab_read();
 141         }
 142         if (!new_cache) {
 143                 xtab_mount_read();
 144                 exports_update(f_verbose);
 145         }
 146         xtab_export_write();
 147         if (new_cache)
 148                 cache_flush(force_flush);
 149         if (!new_cache)
 150                 xtab_mount_write();
 151
 152         return export_errno;
 153 }
 154
 155 static void
 156 exports_update_one(nfs_export *exp, int verbose)
 157 {
 158                 /* check mountpoint option */
 159         if (exp->m_mayexport &&
 160             exp->m_export.e_mountpoint &&
 161             !is_mountpoint(exp->m_export.e_mountpoint[0]?
 162                            exp->m_export.e_mountpoint:
 163                            exp->m_export.e_path)) {
 164                 printf("%s not exported as %s not a mountpoint.\n",
 165                        exp->m_export.e_path, exp->m_export.e_mountpoint);
 166                 exp->m_mayexport = 0;
 167         }
 168         if (exp->m_mayexport && ((exp->m_exported<1) || exp->m_changed)) {
 169                 if (verbose)
 170                         printf("%sexporting %s:%s to kernel\n",
 171                                exp->m_exported ?"re":"",
 172                                exp->m_client->m_hostname,
 173                                exp->m_export.e_path);
 174                 if (!export_export(exp))
 175                         error(exp, errno);
 176         }
 177         if (exp->m_exported && ! exp->m_mayexport) {
 178                 if (verbose)
 179                         printf("unexporting %s:%s from kernel\n",
 180                                exp->m_client->m_hostname,
 181                                exp->m_export.e_path);
 182                 if (!export_unexport(exp))
 183                         error(exp, errno);
 184         }
 185 }
 186
 187
 188 /* we synchronise intention with reality.
 189  * entries with m_mayexport get exported
 190  * entries with m_exported but not m_mayexport get unexported
 191  * looking at m_client->m_type == MCL_FQDN and m_client->m_type == MCL_GSS only
 192  */
 193 static void
 194 exports_update(int verbose)
 195 {
 196         nfs_export      *exp;
 197
 198         for (exp = exportlist[MCL_FQDN].p_head; exp; exp=exp->m_next) {
 199                 exports_update_one(exp, verbose);
 200         }
 201         for (exp = exportlist[MCL_GSS].p_head; exp; exp=exp->m_next) {
 202                 exports_update_one(exp, verbose);
 203         }
 204 }
 205
 206 /*
 207  * export_all finds all entries and
 208  *    marks them xtabent and mayexport so that they get exported
 209  */
 210 static void
 211 export_all(int verbose)
 212 {
 213         nfs_export      *exp;
 214         int             i;
 215
 216         for (i = 0; i < MCL_MAXTYPES; i++) {
 217                 for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
 218                         if (verbose)
 219                                 printf("exporting %s:%s\n",
 220                                        exp->m_client->m_hostname,
 221                                        exp->m_export.e_path);
 222                         exp->m_xtabent = 1;
 223                         exp->m_mayexport = 1;
 224                         exp->m_changed = 1;
 225                         exp->m_warned = 0;
 226                         validate_export(exp);
 227                 }
 228         }
 229 }
 230
 231
 232 static void
 233 exportfs(char *arg, char *options, int verbose)
 234 {
 235         struct exportent *eep;
 236         nfs_export      *exp;
 237         struct addrinfo *ai = NULL;
 238         char            *path;
 239         char            *hname = arg;
 240         int             htype;
 241
 242         if ((path = strchr(arg, ':')) != NULL)
 243                 *path++ = '\0';
 244
 245         if (!path || *path != '/') {
 246                 fprintf(stderr, "Invalid exporting option: %s\n", arg);
 247                 return;
 248         }
 249
 250         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 251                 ai = host_addrinfo(hname);
 252                 if (ai != NULL) {
 253                         exp = export_find(ai, path);
 254                         hname = ai->ai_canonname;
 255                 }
 256         } else
 257                 exp = export_lookup(hname, path, 0);
 258
 259         if (!exp) {
 260                 if (!(eep = mkexportent(hname, path, options)) ||
 261                     !(exp = export_create(eep, 0)))
 262                         goto out;
 263         } else if (!updateexportent(&exp->m_export, options))
 264                 goto out;
 265
 266         if (verbose)
 267                 printf("exporting %s:%s\n", exp->m_client->m_hostname,
 268                         exp->m_export.e_path);
 269         exp->m_xtabent = 1;
 270         exp->m_mayexport = 1;
 271         exp->m_changed = 1;
 272         exp->m_warned = 0;
 273         validate_export(exp);
 274
 275 out:
 276         freeaddrinfo(ai);
 277 }
 278
 279 static void
 280 unexportfs(char *arg, int verbose)
 281 {
 282         nfs_export      *exp;
 283         struct addrinfo *ai = NULL;
 284         char            *path;
 285         char            *hname = arg;
 286         int             htype;
 287
 288         if ((path = strchr(arg, ':')) != NULL)
 289                 *path++ = '\0';
 290
 291         if (!path || *path != '/') {
 292                 fprintf(stderr, "Invalid unexporting option: %s\n",
 293                         arg);
 294                 return;
 295         }
 296
 297         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 298                 ai = host_addrinfo(hname);
 299                 if (ai)
 300                         hname = ai->ai_canonname;
 301         }
 302
 303         for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 304                 if (path && strcmp(path, exp->m_export.e_path))
 305                         continue;
 306                 if (htype != exp->m_client->m_type)
 307                         continue;
 308                 if (htype == MCL_FQDN
 309                     && !matchhostname(exp->m_export.e_hostname,
 310                                           hname))
 311                         continue;
 312                 if (htype != MCL_FQDN
 313                     && strcasecmp(exp->m_export.e_hostname, hname))
 314                         continue;
 315                 if (verbose) {
 316 #if 0
 317                         if (exp->m_exported) {
 318                                 printf("unexporting %s:%s from kernel\n",
 319                                        exp->m_client->m_hostname,
 320                                        exp->m_export.e_path);
 321                         }
 322                         else
 323 #endif
 324                                 printf("unexporting %s:%s\n",
 325                                         exp->m_client->m_hostname,
 326                                         exp->m_export.e_path);
 327                 }
 328 #if 0
 329                 if (exp->m_exported && !export_unexport(exp))
 330                         error(exp, errno);
 331 #endif
 332                 exp->m_xtabent = 0;
 333                 exp->m_mayexport = 0;
 334         }
 335
 336         freeaddrinfo(ai);
 337 }
 338
 339 static int can_test(void)
 340 {
 341         int fd;
 342         int n;
 343         char *setup = "nfsd 0.0.0.0 2147483647 -test-client-\n";
 344         fd = open("/proc/net/rpc/auth.unix.ip/channel", O_WRONLY);
 345         if ( fd < 0) return 0;
 346         n = write(fd, setup, strlen(setup));
 347         close(fd);
 348         if (n < 0)
 349                 return 0;
 350         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 351         if ( fd < 0) return 0;
 352         close(fd);
 353         return 1;
 354 }
 355
 356 static int test_export(char *path, int with_fsid)
 357 {
 358         char buf[1024];
 359         int fd, n;
 360
 361         sprintf(buf, "-test-client- %s 3 %d -1 -1 0\n",
 362                 path,
 363                 with_fsid ? NFSEXP_FSID : 0);
 364         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 365         if (fd < 0)
 366                 return 0;
 367         n = write(fd, buf, strlen(buf));
 368         close(fd);
 369         if (n < 0)
 370                 return 0;
 371         return 1;
 372 }
 373
 374 static void
 375 validate_export(nfs_export *exp)
 376 {
 377         /* Check that the given export point is potentially exportable.
 378          * We just give warnings here, don't cause anything to fail.
 379          * If a path doesn't exist, or is not a dir or file, give an warning
 380          * otherwise trial-export to '-test-client-' and check for failure.
 381          */
 382         struct stat stb;
 383         char *path = exp->m_export.e_path;
 384         struct statfs64 stf;
 385         int fs_has_fsid = 0;
 386
 387         if (stat(path, &stb) < 0) {
 388                 fprintf(stderr, "exportfs: Warning: %s does not exist\n",
 389                         path);
 390                 return;
 391         }
 392         if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
 393                 fprintf(stderr, "exportfs: Warning: %s is neither "
 394                         "a directory nor a file.\n"
 395                         "     remote access will fail\n", path);
 396                 return;
 397         }
 398         if (!can_test())
 399                 return;
 400
 401         if (!statfs64(path, &stf) &&
 402             (stf.f_fsid.__val[0] || stf.f_fsid.__val[1]))
 403                 fs_has_fsid = 1;
 404
 405         if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
 406             fs_has_fsid) {
 407                 if ( !test_export(path, 1)) {
 408                         fprintf(stderr, "exportfs: Warning: %s does not "
 409                                 "support NFS export.\n",
 410                                 path);
 411                         return;
 412                 }
 413         } else if ( ! test_export(path, 0)) {
 414                 if (test_export(path, 1))
 415                         fprintf(stderr, "exportfs: Warning: %s requires fsid= "
 416                                 "for NFS export\n", path);
 417                 else
 418                         fprintf(stderr, "exportfs: Warning: %s does not "
 419                                 "support NFS export.\n",
 420                                 path);
 421                 return;
 422
 423         }
 424 }
 425
 426 static _Bool
 427 is_hostname(const char *sp)
 428 {
 429         if (*sp == '\0' || *sp == '@')
 430                 return false;
 431
 432         for (; *sp != '\0'; sp++) {
 433                 if (*sp == '*' || *sp == '?' || *sp == '[' || *sp == '/')
 434                         return false;
 435                 if (*sp == '\\' && sp[1] != '\0')
 436                         sp++;
 437         }
 438
 439         return true;
 440 }
 441
 442 static _Bool
 443 compare_sockaddrs4(const struct sockaddr *sa1, const struct sockaddr *sa2)
 444 {
 445         const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
 446         const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
 447         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 448 }
 449
 450 static _Bool
 451 compare_sockaddrs(const struct sockaddr *sa1, const struct sockaddr *sa2)
 452 {
 453         if (sa1->sa_family == sa2->sa_family)
 454                 switch (sa1->sa_family) {
 455                 case AF_INET:
 456                         return compare_sockaddrs4(sa1, sa2);
 457                 }
 458
 459         return false;
 460 }
 461
 462 static int
 463 matchhostname(const char *hostname1, const char *hostname2)
 464 {
 465         struct addrinfo *results1 = NULL, *results2 = NULL;
 466         struct addrinfo *ai1, *ai2;
 467         int result = 0;
 468
 469         if (strcasecmp(hostname1, hostname2) == 0)
 470                 return 1;
 471
 472         /*
 473          * Don't pass export wildcards or netgroup names to DNS
 474          */
 475         if (!is_hostname(hostname1) || !is_hostname(hostname2))
 476                 return 0;
 477
 478         results1 = host_addrinfo(hostname1);
 479         if (results1 == NULL)
 480                 goto out;
 481         results2 = host_addrinfo(hostname2);
 482         if (results2 == NULL)
 483                 goto out;
 484
 485         if (strcasecmp(results1->ai_canonname, results2->ai_canonname) == 0) {
 486                 result = 1;
 487                 goto out;
 488         }
 489
 490         for (ai1 = results1; ai1 != NULL; ai1 = ai1->ai_next)
 491                 for (ai2 = results2; ai2 != NULL; ai2 = ai2->ai_next)
 492                         if (compare_sockaddrs(ai1->ai_addr, ai2->ai_addr)) {
 493                                 result = 1;
 494                                 break;
 495                         }
 496
 497 out:
 498         freeaddrinfo(results1);
 499         freeaddrinfo(results2);
 500         return result;
 501 }
 502
 503 static char
 504 dumpopt(char c, char *fmt, ...)
 505 {
 506         va_list ap;
 507
 508         va_start(ap, fmt);
 509         printf("%c", c);
 510         vprintf(fmt, ap);
 511         va_end(ap);
 512         return ',';
 513 }
 514
 515 static void
 516 dump(int verbose)
 517 {
 518         nfs_export      *exp;
 519         struct exportent *ep;
 520         int             htype;
 521         char            *hname, c;
 522
 523         for (htype = 0; htype < MCL_MAXTYPES; htype++) {
 524                 for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 525                         ep = &exp->m_export;
 526                         if (!exp->m_xtabent)
 527                             continue; /* neilb */
 528                         if (htype == MCL_ANONYMOUS)
 529                                 hname = "<world>";
 530                         else
 531                                 hname = ep->e_hostname;
 532                         if (strlen(ep->e_path) > 14)
 533                                 printf("%-14s\n\t\t%s", ep->e_path, hname);
 534                         else
 535                                 printf("%-14s\t%s", ep->e_path, hname);
 536                         if (!verbose) {
 537                                 printf("\n");
 538                                 continue;
 539                         }
 540                         c = '(';
 541                         if (ep->e_flags & NFSEXP_READONLY)
 542                                 c = dumpopt(c, "ro");
 543                         else
 544                                 c = dumpopt(c, "rw");
 545                         if (ep->e_flags & NFSEXP_ASYNC)
 546                                 c = dumpopt(c, "async");
 547                         if (ep->e_flags & NFSEXP_GATHERED_WRITES)
 548                                 c = dumpopt(c, "wdelay");
 549                         if (ep->e_flags & NFSEXP_NOHIDE)
 550                                 c = dumpopt(c, "nohide");
 551                         if (ep->e_flags & NFSEXP_CROSSMOUNT)
 552                                 c = dumpopt(c, "crossmnt");
 553                         if (ep->e_flags & NFSEXP_INSECURE_PORT)
 554                                 c = dumpopt(c, "insecure");
 555                         if (ep->e_flags & NFSEXP_ROOTSQUASH)
 556                                 c = dumpopt(c, "root_squash");
 557                         else
 558                                 c = dumpopt(c, "no_root_squash");
 559                         if (ep->e_flags & NFSEXP_ALLSQUASH)
 560                                 c = dumpopt(c, "all_squash");
 561                         if (ep->e_flags & NFSEXP_NOSUBTREECHECK)
 562                                 c = dumpopt(c, "no_subtree_check");
 563                         if (ep->e_flags & NFSEXP_NOAUTHNLM)
 564                                 c = dumpopt(c, "insecure_locks");
 565                         if (ep->e_flags & NFSEXP_NOACL)
 566                                 c = dumpopt(c, "no_acl");
 567                         if (ep->e_flags & NFSEXP_FSID)
 568                                 c = dumpopt(c, "fsid=%d", ep->e_fsid);
 569                         if (ep->e_uuid)
 570                                 c = dumpopt(c, "fsid=%s", ep->e_uuid);
 571                         if (ep->e_mountpoint)
 572                                 c = dumpopt(c, "mountpoint%s%s",
 573                                             ep->e_mountpoint[0]?"=":"",
 574                                             ep->e_mountpoint);
 575                         if (ep->e_anonuid != 65534)
 576                                 c = dumpopt(c, "anonuid=%d", ep->e_anonuid);
 577                         if (ep->e_anongid != 65534)
 578                                 c = dumpopt(c, "anongid=%d", ep->e_anongid);
 579                         switch(ep->e_fslocmethod) {
 580                         case FSLOC_NONE:
 581                                 break;
 582                         case FSLOC_REFER:
 583                                 c = dumpopt(c, "refer=%s", ep->e_fslocdata);
 584                                 break;
 585                         case FSLOC_REPLICA:
 586                                 c = dumpopt(c, "replicas=%s", ep->e_fslocdata);
 587                                 break;
 588 #ifdef DEBUG
 589                         case FSLOC_STUB:
 590                                 c = dumpopt(c, "fsloc=stub");
 591                                 break;
 592 #endif
 593                         }
 594                         secinfo_show(stdout, ep);
 595                         printf("%c\n", (c != '(')? ')' : ' ');
 596                 }
 597         }
 598 }
 599
 600 static void
 601 error(nfs_export *exp, int err)
 602 {
 603         fprintf(stderr, "%s:%s: %s\n", exp->m_client->m_hostname,
 604                 exp->m_export.e_path, strerror(err));
 605 }
 606
 607 static void
 608 usage(void)
 609 {
 610         fprintf(stderr, "usage: exportfs [-aruv] [host:/path]\n");
 611         exit(1);
 612 }