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
  29 #include "misc.h"
  30 #include "nfslib.h"
  31 #include "exportfs.h"
  32 #include "xlog.h"
  33
  34 static void     export_all(int verbose);
  35 static void     exportfs(char *arg, char *options, int verbose);
  36 static void     unexportfs(char *arg, int verbose);
  37 static void     exports_update(int verbose);
  38 static void     dump(int verbose);
  39 static void     error(nfs_export *exp, int err);
  40 static void     usage(void);
  41 static void     validate_export(nfs_export *exp);
  42 static int      matchhostname(const char *hostname1, const char *hostname2);
  43
  44 int
  45 main(int argc, char **argv)
  46 {
  47         char    *options = NULL;
  48         int     f_export = 1;
  49         int     f_all = 0;
  50         int     f_verbose = 0;
  51         int     f_reexport = 0;
  52         int     f_ignore = 0;
  53         int     i, c;
  54         int     new_cache = 0;
  55         int     force_flush = 0;
  56
  57         xlog_open("exportfs");
  58
  59         export_errno = 0;
  60
  61         while ((c = getopt(argc, argv, "aio:ruvf")) != EOF) {
  62                 switch(c) {
  63                 case 'a':
  64                         f_all = 1;
  65                         break;
  66                 case 'i':
  67                         f_ignore = 1;
  68                         break;
  69                 case 'o':
  70                         options = optarg;
  71                         break;
  72                 case 'r':
  73                         f_reexport = 1;
  74                         f_all = 1;
  75                         break;
  76                 case 'u':
  77                         f_export = 0;
  78                         break;
  79                 case 'v':
  80                         f_verbose = 1;
  81                         break;
  82                 case 'f':
  83                         force_flush = 1;
  84                         break;
  85                 default:
  86                         usage();
  87                         break;
  88                 }
  89         }
  90
  91         if (optind != argc && f_all) {
  92                 fprintf(stderr,"exportfs: extra arguments are not permitted with -a or -r.\n");
  93                 return 1;
  94         }
  95         if (f_ignore && (f_all || ! f_export)) {
  96                 fprintf(stderr,"exportfs: -i not meaningful with -a, -r or -u.\n");
  97                 return 1;
  98         }
  99         if (f_reexport && ! f_export) {
 100                 fprintf(stderr, "exportfs: -r and -u are incompatible.\n");
 101                 return 1;
 102         }
 103         new_cache = check_new_cache();
 104         if (optind == argc && ! f_all) {
 105                 if (force_flush) {
 106                         if (new_cache)
 107                                 cache_flush(1);
 108                         else {
 109                                 fprintf(stderr, "exportfs: -f: only available with new cache controls: mount /proc/fs/nfsd first\n");
 110                                 exit(1);
 111                         }
 112                         return 0;
 113                 } else {
 114                         xtab_export_read();
 115                         dump(f_verbose);
 116                         return 0;
 117                 }
 118         }
 119         if (f_export && ! f_ignore)
 120                 export_read(_PATH_EXPORTS);
 121         if (f_export) {
 122                 if (f_all)
 123                         export_all(f_verbose);
 124                 else
 125                         for (i = optind; i < argc ; i++)
 126                                 exportfs(argv[i], options, f_verbose);
 127         }
 128         /* If we are unexporting everything, then
 129          * don't care about what should be exported, as that
 130          * may require DNS lookups..
 131          */
 132         if (! ( !f_export && f_all)) {
 133                 /* note: xtab_*_read does not update entries if they already exist,
 134                  * so this will not lose new options
 135                  */
 136                 if (!f_reexport)
 137                         xtab_export_read();
 138                 if (!f_export)
 139                         for (i = optind ; i < argc ; i++)
 140                                 unexportfs(argv[i], f_verbose);
 141                 if (!new_cache)
 142                         rmtab_read();
 143         }
 144         if (!new_cache) {
 145                 xtab_mount_read();
 146                 exports_update(f_verbose);
 147         }
 148         xtab_export_write();
 149         if (new_cache)
 150                 cache_flush(force_flush);
 151         if (!new_cache)
 152                 xtab_mount_write();
 153
 154         return export_errno;
 155 }
 156
 157 static void
 158 exports_update_one(nfs_export *exp, int verbose)
 159 {
 160                 /* check mountpoint option */
 161         if (exp->m_mayexport &&
 162             exp->m_export.e_mountpoint &&
 163             !is_mountpoint(exp->m_export.e_mountpoint[0]?
 164                            exp->m_export.e_mountpoint:
 165                            exp->m_export.e_path)) {
 166                 printf("%s not exported as %s not a mountpoint.\n",
 167                        exp->m_export.e_path, exp->m_export.e_mountpoint);
 168                 exp->m_mayexport = 0;
 169         }
 170         if (exp->m_mayexport && ((exp->m_exported<1) || exp->m_changed)) {
 171                 if (verbose)
 172                         printf("%sexporting %s:%s to kernel\n",
 173                                exp->m_exported ?"re":"",
 174                                exp->m_client->m_hostname,
 175                                exp->m_export.e_path);
 176                 if (!export_export(exp))
 177                         error(exp, errno);
 178         }
 179         if (exp->m_exported && ! exp->m_mayexport) {
 180                 if (verbose)
 181                         printf("unexporting %s:%s from kernel\n",
 182                                exp->m_client->m_hostname,
 183                                exp->m_export.e_path);
 184                 if (!export_unexport(exp))
 185                         error(exp, errno);
 186         }
 187 }
 188
 189
 190 /* we synchronise intention with reality.
 191  * entries with m_mayexport get exported
 192  * entries with m_exported but not m_mayexport get unexported
 193  * looking at m_client->m_type == MCL_FQDN and m_client->m_type == MCL_GSS only
 194  */
 195 static void
 196 exports_update(int verbose)
 197 {
 198         nfs_export      *exp;
 199
 200         for (exp = exportlist[MCL_FQDN].p_head; exp; exp=exp->m_next) {
 201                 exports_update_one(exp, verbose);
 202         }
 203         for (exp = exportlist[MCL_GSS].p_head; exp; exp=exp->m_next) {
 204                 exports_update_one(exp, verbose);
 205         }
 206 }
 207
 208 /*
 209  * export_all finds all entries and
 210  *    marks them xtabent and mayexport so that they get exported
 211  */
 212 static void
 213 export_all(int verbose)
 214 {
 215         nfs_export      *exp;
 216         int             i;
 217
 218         for (i = 0; i < MCL_MAXTYPES; i++) {
 219                 for (exp = exportlist[i].p_head; exp; exp = exp->m_next) {
 220                         if (verbose)
 221                                 printf("exporting %s:%s\n",
 222                                        exp->m_client->m_hostname,
 223                                        exp->m_export.e_path);
 224                         exp->m_xtabent = 1;
 225                         exp->m_mayexport = 1;
 226                         exp->m_changed = 1;
 227                         exp->m_warned = 0;
 228                         validate_export(exp);
 229                 }
 230         }
 231 }
 232
 233
 234 static void
 235 exportfs(char *arg, char *options, int verbose)
 236 {
 237         struct exportent *eep;
 238         nfs_export      *exp;
 239         struct addrinfo *ai = NULL;
 240         char            *path;
 241         char            *hname = arg;
 242         int             htype;
 243
 244         if ((path = strchr(arg, ':')) != NULL)
 245                 *path++ = '\0';
 246
 247         if (!path || *path != '/') {
 248                 fprintf(stderr, "Invalid exporting option: %s\n", arg);
 249                 return;
 250         }
 251
 252         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 253                 ai = host_addrinfo(hname);
 254                 if (ai != NULL) {
 255                         exp = export_find(ai, path);
 256                         hname = ai->ai_canonname;
 257                 }
 258         } else
 259                 exp = export_lookup(hname, path, 0);
 260
 261         if (!exp) {
 262                 if (!(eep = mkexportent(hname, path, options)) ||
 263                     !(exp = export_create(eep, 0)))
 264                         goto out;
 265         } else if (!updateexportent(&exp->m_export, options))
 266                 goto out;
 267
 268         if (verbose)
 269                 printf("exporting %s:%s\n", exp->m_client->m_hostname,
 270                         exp->m_export.e_path);
 271         exp->m_xtabent = 1;
 272         exp->m_mayexport = 1;
 273         exp->m_changed = 1;
 274         exp->m_warned = 0;
 275         validate_export(exp);
 276
 277 out:
 278         freeaddrinfo(ai);
 279 }
 280
 281 static void
 282 unexportfs(char *arg, int verbose)
 283 {
 284         nfs_export      *exp;
 285         struct addrinfo *ai = NULL;
 286         char            *path;
 287         char            *hname = arg;
 288         int             htype;
 289
 290         if ((path = strchr(arg, ':')) != NULL)
 291                 *path++ = '\0';
 292
 293         if (!path || *path != '/') {
 294                 fprintf(stderr, "Invalid unexporting option: %s\n",
 295                         arg);
 296                 return;
 297         }
 298
 299         if ((htype = client_gettype(hname)) == MCL_FQDN) {
 300                 ai = host_addrinfo(hname);
 301                 if (ai)
 302                         hname = ai->ai_canonname;
 303         }
 304
 305         for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 306                 if (path && strcmp(path, exp->m_export.e_path))
 307                         continue;
 308                 if (htype != exp->m_client->m_type)
 309                         continue;
 310                 if (htype == MCL_FQDN
 311                     && !matchhostname(exp->m_export.e_hostname,
 312                                           hname))
 313                         continue;
 314                 if (htype != MCL_FQDN
 315                     && strcasecmp(exp->m_export.e_hostname, hname))
 316                         continue;
 317                 if (verbose) {
 318 #if 0
 319                         if (exp->m_exported) {
 320                                 printf("unexporting %s:%s from kernel\n",
 321                                        exp->m_client->m_hostname,
 322                                        exp->m_export.e_path);
 323                         }
 324                         else
 325 #endif
 326                                 printf("unexporting %s:%s\n",
 327                                         exp->m_client->m_hostname,
 328                                         exp->m_export.e_path);
 329                 }
 330 #if 0
 331                 if (exp->m_exported && !export_unexport(exp))
 332                         error(exp, errno);
 333 #endif
 334                 exp->m_xtabent = 0;
 335                 exp->m_mayexport = 0;
 336         }
 337
 338         freeaddrinfo(ai);
 339 }
 340
 341 static int can_test(void)
 342 {
 343         int fd;
 344         int n;
 345         char *setup = "nfsd 0.0.0.0 2147483647 -test-client-\n";
 346         fd = open("/proc/net/rpc/auth.unix.ip/channel", O_WRONLY);
 347         if ( fd < 0) return 0;
 348         n = write(fd, setup, strlen(setup));
 349         close(fd);
 350         if (n < 0)
 351                 return 0;
 352         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 353         if ( fd < 0) return 0;
 354         close(fd);
 355         return 1;
 356 }
 357
 358 static int test_export(char *path, int with_fsid)
 359 {
 360         char buf[1024];
 361         int fd, n;
 362
 363         sprintf(buf, "-test-client- %s 3 %d -1 -1 0\n",
 364                 path,
 365                 with_fsid ? NFSEXP_FSID : 0);
 366         fd = open("/proc/net/rpc/nfsd.export/channel", O_WRONLY);
 367         if (fd < 0)
 368                 return 0;
 369         n = write(fd, buf, strlen(buf));
 370         close(fd);
 371         if (n < 0)
 372                 return 0;
 373         return 1;
 374 }
 375
 376 static void
 377 validate_export(nfs_export *exp)
 378 {
 379         /* Check that the given export point is potentially exportable.
 380          * We just give warnings here, don't cause anything to fail.
 381          * If a path doesn't exist, or is not a dir or file, give an warning
 382          * otherwise trial-export to '-test-client-' and check for failure.
 383          */
 384         struct stat stb;
 385         char *path = exp->m_export.e_path;
 386         struct statfs64 stf;
 387         int fs_has_fsid = 0;
 388
 389         if (stat(path, &stb) < 0) {
 390                 fprintf(stderr, "exportfs: Warning: %s does not exist\n",
 391                         path);
 392                 return;
 393         }
 394         if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
 395                 fprintf(stderr, "exportfs: Warning: %s is neither "
 396                         "a directory nor a file.\n"
 397                         "     remote access will fail\n", path);
 398                 return;
 399         }
 400         if (!can_test())
 401                 return;
 402
 403         if (!statfs64(path, &stf) &&
 404             (stf.f_fsid.__val[0] || stf.f_fsid.__val[1]))
 405                 fs_has_fsid = 1;
 406
 407         if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
 408             fs_has_fsid) {
 409                 if ( !test_export(path, 1)) {
 410                         fprintf(stderr, "exportfs: Warning: %s does not "
 411                                 "support NFS export.\n",
 412                                 path);
 413                         return;
 414                 }
 415         } else if ( ! test_export(path, 0)) {
 416                 if (test_export(path, 1))
 417                         fprintf(stderr, "exportfs: Warning: %s requires fsid= "
 418                                 "for NFS export\n", path);
 419                 else
 420                         fprintf(stderr, "exportfs: Warning: %s does not "
 421                                 "support NFS export.\n",
 422                                 path);
 423                 return;
 424
 425         }
 426 }
 427
 428 static _Bool
 429 is_hostname(const char *sp)
 430 {
 431         if (*sp == '\0' || *sp == '@')
 432                 return false;
 433
 434         for (; *sp != '\0'; sp++) {
 435                 if (*sp == '*' || *sp == '?' || *sp == '[' || *sp == '/')
 436                         return false;
 437                 if (*sp == '\\' && sp[1] != '\0')
 438                         sp++;
 439         }
 440
 441         return true;
 442 }
 443
 444 static _Bool
 445 compare_sockaddrs4(const struct sockaddr *sa1, const struct sockaddr *sa2)
 446 {
 447         const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sa1;
 448         const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sa2;
 449         return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
 450 }
 451
 452 static _Bool
 453 compare_sockaddrs(const struct sockaddr *sa1, const struct sockaddr *sa2)
 454 {
 455         if (sa1->sa_family == sa2->sa_family)
 456                 switch (sa1->sa_family) {
 457                 case AF_INET:
 458                         return compare_sockaddrs4(sa1, sa2);
 459                 }
 460
 461         return false;
 462 }
 463
 464 static int
 465 matchhostname(const char *hostname1, const char *hostname2)
 466 {
 467         struct addrinfo *results1 = NULL, *results2 = NULL;
 468         struct addrinfo *ai1, *ai2;
 469         int result = 0;
 470
 471         if (strcasecmp(hostname1, hostname2) == 0)
 472                 return 1;
 473
 474         /*
 475          * Don't pass export wildcards or netgroup names to DNS
 476          */
 477         if (!is_hostname(hostname1) || !is_hostname(hostname2))
 478                 return 0;
 479
 480         results1 = host_addrinfo(hostname1);
 481         if (results1 == NULL)
 482                 goto out;
 483         results2 = host_addrinfo(hostname2);
 484         if (results2 == NULL)
 485                 goto out;
 486
 487         if (strcasecmp(results1->ai_canonname, results2->ai_canonname) == 0) {
 488                 result = 1;
 489                 goto out;
 490         }
 491
 492         for (ai1 = results1; ai1 != NULL; ai1 = ai1->ai_next)
 493                 for (ai2 = results2; ai2 != NULL; ai2 = ai2->ai_next)
 494                         if (compare_sockaddrs(ai1->ai_addr, ai2->ai_addr)) {
 495                                 result = 1;
 496                                 break;
 497                         }
 498
 499 out:
 500         freeaddrinfo(results1);
 501         freeaddrinfo(results2);
 502         return result;
 503 }
 504
 505 static char
 506 dumpopt(char c, char *fmt, ...)
 507 {
 508         va_list ap;
 509
 510         va_start(ap, fmt);
 511         printf("%c", c);
 512         vprintf(fmt, ap);
 513         va_end(ap);
 514         return ',';
 515 }
 516
 517 static void
 518 dump(int verbose)
 519 {
 520         nfs_export      *exp;
 521         struct exportent *ep;
 522         int             htype;
 523         char            *hname, c;
 524
 525         for (htype = 0; htype < MCL_MAXTYPES; htype++) {
 526                 for (exp = exportlist[htype].p_head; exp; exp = exp->m_next) {
 527                         ep = &exp->m_export;
 528                         if (!exp->m_xtabent)
 529                             continue; /* neilb */
 530                         if (htype == MCL_ANONYMOUS)
 531                                 hname = "<world>";
 532                         else
 533                                 hname = ep->e_hostname;
 534                         if (strlen(ep->e_path) > 14)
 535                                 printf("%-14s\n\t\t%s", ep->e_path, hname);
 536                         else
 537                                 printf("%-14s\t%s", ep->e_path, hname);
 538                         if (!verbose) {
 539                                 printf("\n");
 540                                 continue;
 541                         }
 542                         c = '(';
 543                         if (ep->e_flags & NFSEXP_READONLY)
 544                                 c = dumpopt(c, "ro");
 545                         else
 546                                 c = dumpopt(c, "rw");
 547                         if (ep->e_flags & NFSEXP_ASYNC)
 548                                 c = dumpopt(c, "async");
 549                         if (ep->e_flags & NFSEXP_GATHERED_WRITES)
 550                                 c = dumpopt(c, "wdelay");
 551                         if (ep->e_flags & NFSEXP_NOHIDE)
 552                                 c = dumpopt(c, "nohide");
 553                         if (ep->e_flags & NFSEXP_CROSSMOUNT)
 554                                 c = dumpopt(c, "crossmnt");
 555                         if (ep->e_flags & NFSEXP_INSECURE_PORT)
 556                                 c = dumpopt(c, "insecure");
 557                         if (ep->e_flags & NFSEXP_ROOTSQUASH)
 558                                 c = dumpopt(c, "root_squash");
 559                         else
 560                                 c = dumpopt(c, "no_root_squash");
 561                         if (ep->e_flags & NFSEXP_ALLSQUASH)
 562                                 c = dumpopt(c, "all_squash");
 563                         if (ep->e_flags & NFSEXP_NOSUBTREECHECK)
 564                                 c = dumpopt(c, "no_subtree_check");
 565                         if (ep->e_flags & NFSEXP_NOAUTHNLM)
 566                                 c = dumpopt(c, "insecure_locks");
 567                         if (ep->e_flags & NFSEXP_NOACL)
 568                                 c = dumpopt(c, "no_acl");
 569                         if (ep->e_flags & NFSEXP_FSID)
 570                                 c = dumpopt(c, "fsid=%d", ep->e_fsid);
 571                         if (ep->e_uuid)
 572                                 c = dumpopt(c, "fsid=%s", ep->e_uuid);
 573                         if (ep->e_mountpoint)
 574                                 c = dumpopt(c, "mountpoint%s%s",
 575                                             ep->e_mountpoint[0]?"=":"",
 576                                             ep->e_mountpoint);
 577                         if (ep->e_anonuid != 65534)
 578                                 c = dumpopt(c, "anonuid=%d", ep->e_anonuid);
 579                         if (ep->e_anongid != 65534)
 580                                 c = dumpopt(c, "anongid=%d", ep->e_anongid);
 581                         switch(ep->e_fslocmethod) {
 582                         case FSLOC_NONE:
 583                                 break;
 584                         case FSLOC_REFER:
 585                                 c = dumpopt(c, "refer=%s", ep->e_fslocdata);
 586                                 break;
 587                         case FSLOC_REPLICA:
 588                                 c = dumpopt(c, "replicas=%s", ep->e_fslocdata);
 589                                 break;
 590 #ifdef DEBUG
 591                         case FSLOC_STUB:
 592                                 c = dumpopt(c, "fsloc=stub");
 593                                 break;
 594 #endif
 595                         }
 596                         secinfo_show(stdout, ep);
 597                         printf("%c\n", (c != '(')? ')' : ' ');
 598                 }
 599         }
 600 }
 601
 602 static void
 603 error(nfs_export *exp, int err)
 604 {
 605         fprintf(stderr, "%s:%s: %s\n", exp->m_client->m_hostname,
 606                 exp->m_export.e_path, strerror(err));
 607 }
 608
 609 static void
 610 usage(void)
 611 {
 612         fprintf(stderr, "usage: exportfs [-aruv] [host:/path]\n");
 613         exit(1);
 614 }