src/tmpfiles.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 Lennart Poettering, Kay Sievers
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU General Public License as published by
  10   the Free Software Foundation; either version 2 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   General Public License for more details.
  17
  18   You should have received a copy of the GNU General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <unistd.h>
  23 #include <fcntl.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <sys/stat.h>
  27 #include <limits.h>
  28 #include <dirent.h>
  29 #include <grp.h>
  30 #include <pwd.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <stddef.h>
  34 #include <getopt.h>
  35 #include <stdbool.h>
  36 #include <time.h>
  37 #include <sys/types.h>
  38 #include <sys/param.h>
  39
  40 #include "log.h"
  41 #include "util.h"
  42 #include "strv.h"
  43 #include "label.h"
  44 #include "set.h"
  45
  46 /* This reads all files listed in /etc/tmpfiles.d/?*.conf and creates
  47  * them in the file system. This is intended to be used to create
  48  * properly owned directories beneath /tmp, /var/tmp, /var/run and
  49  * /var/lock which are volatile and hence need to be recreated on
  50  * bootup. */
  51
  52 enum {
  53         CREATE_FILE = 'f',
  54         TRUNCATE_FILE = 'F',
  55         CREATE_DIRECTORY = 'd',
  56         TRUNCATE_DIRECTORY = 'D',
  57         IGNORE_PATH = 'x',
  58         REMOVE_PATH = 'r',
  59         RECURSIVE_REMOVE_PATH = 'R'
  60 };
  61
  62 typedef struct Item {
  63         char type;
  64
  65         char *path;
  66         uid_t uid;
  67         gid_t gid;
  68         mode_t mode;
  69         usec_t age;
  70
  71         bool uid_set:1;
  72         bool gid_set:1;
  73         bool mode_set:1;
  74         bool age_set:1;
  75 } Item;
  76
  77 static Hashmap *items = NULL;
  78
  79 static bool arg_create = false;
  80 static bool arg_clean = false;
  81 static bool arg_remove = false;
  82
  83 #define MAX_DEPTH 256
  84
  85 static int dir_cleanup(
  86                 const char *p,
  87                 DIR *d,
  88                 const struct stat *ds,
  89                 usec_t cutoff,
  90                 dev_t rootdev,
  91                 bool mountpoint,
  92                 int maxdepth)
  93 {
  94         struct dirent *dent;
  95         struct timespec times[2];
  96         bool deleted = false;
  97         char *sub_path = NULL;
  98         int r = 0;
  99
 100         while ((dent = readdir(d))) {
 101                 struct stat s;
 102                 usec_t age;
 103
 104                 if (streq(dent->d_name, ".") ||
 105                     streq(dent->d_name, ".."))
 106                         continue;
 107
 108                 if (fstatat(dirfd(d), dent->d_name, &s, AT_SYMLINK_NOFOLLOW) < 0) {
 109
 110                         if (errno != ENOENT) {
 111                                 log_error("stat(%s/%s) failed: %m", p, dent->d_name);
 112                                 r = -errno;
 113                         }
 114
 115                         continue;
 116                 }
 117
 118                 /* Stay on the same filesystem */
 119                 if (s.st_dev != rootdev)
 120                         continue;
 121
 122                 /* Do not delete read-only files owned by root */
 123                 if (s.st_uid == 0 && !(s.st_mode & S_IWUSR))
 124                         continue;
 125
 126                 free(sub_path);
 127                 sub_path = NULL;
 128
 129                 if (asprintf(&sub_path, "%s/%s", p, dent->d_name) < 0) {
 130                         log_error("Out of memory");
 131                         r = -ENOMEM;
 132                         goto finish;
 133                 }
 134
 135                 /* Is there an item configured for this path? */
 136                 if (hashmap_get(items, sub_path))
 137                         continue;
 138
 139                 if (S_ISDIR(s.st_mode)) {
 140
 141                         if (mountpoint &&
 142                             streq(dent->d_name, "lost+found") &&
 143                             s.st_uid == 0)
 144                                 continue;
 145
 146                         if (maxdepth <= 0)
 147                                 log_warning("Reached max depth on %s.", sub_path);
 148                         else {
 149                                 DIR *sub_dir;
 150                                 int q;
 151
 152                                 sub_dir = xopendirat(dirfd(d), dent->d_name);
 153                                 if (sub_dir == NULL) {
 154                                         if (errno != ENOENT) {
 155                                                 log_error("opendir(%s/%s) failed: %m", p, dent->d_name);
 156                                                 r = -errno;
 157                                         }
 158
 159                                         continue;
 160                                 }
 161
 162                                 q = dir_cleanup(sub_path, sub_dir, &s, cutoff, rootdev, false, maxdepth-1);
 163                                 closedir(sub_dir);
 164
 165                                 if (q < 0)
 166                                         r = q;
 167                         }
 168
 169                         /* Ignore ctime, we change it when deleting */
 170                         age = MAX(timespec_load(&s.st_mtim),
 171                                   timespec_load(&s.st_atim));
 172                         if (age >= cutoff)
 173                                 continue;
 174
 175                         log_debug("rmdir '%s'\n", sub_path);
 176
 177                         if (unlinkat(dirfd(d), dent->d_name, AT_REMOVEDIR) < 0) {
 178                                 if (errno != ENOENT && errno != ENOTEMPTY) {
 179                                         log_error("rmdir(%s): %m", sub_path);
 180                                         r = -errno;
 181                                 }
 182                         }
 183
 184                 } else {
 185                         if (mountpoint) {
 186                                 if (streq(dent->d_name, ".journal") &&
 187                                     s.st_uid == 0)
 188                                         continue;
 189
 190                                 if (streq(dent->d_name, "aquota.user") ||
 191                                     streq(dent->d_name, "aquota.group"))
 192                                         continue;
 193                         }
 194
 195                         age = MAX3(timespec_load(&s.st_mtim),
 196                                    timespec_load(&s.st_atim),
 197                                    timespec_load(&s.st_ctim));
 198
 199                         if (age >= cutoff)
 200                                 continue;
 201
 202                         log_debug("unlink '%s'\n", sub_path);
 203
 204                         if (unlinkat(dirfd(d), dent->d_name, 0) < 0) {
 205                                 if (errno != ENOENT) {
 206                                         log_error("unlink(%s): %m", sub_path);
 207                                         r = -errno;
 208                                 }
 209                         }
 210
 211                         deleted = true;
 212                 }
 213         }
 214
 215 finish:
 216         if (deleted) {
 217                 /* Restore original directory timestamps */
 218                 times[0] = ds->st_atim;
 219                 times[1] = ds->st_mtim;
 220
 221                 if (futimens(dirfd(d), times) < 0)
 222                         log_error("utimensat(%s): %m", p);
 223         }
 224
 225         free(sub_path);
 226
 227         return r;
 228 }
 229
 230 static int clean_item(Item *i) {
 231         DIR *d;
 232         struct stat s, ps;
 233         bool mountpoint;
 234         int r;
 235         usec_t cutoff, n;
 236
 237         assert(i);
 238
 239         if (i->type != CREATE_DIRECTORY &&
 240             i->type != TRUNCATE_DIRECTORY &&
 241             i->type != IGNORE_PATH)
 242                 return 0;
 243
 244         if (!i->age_set || i->age <= 0)
 245                 return 0;
 246
 247         n = now(CLOCK_REALTIME);
 248         if (n < i->age)
 249                 return 0;
 250
 251         cutoff = n - i->age;
 252
 253         d = opendir(i->path);
 254         if (!d) {
 255                 if (errno == ENOENT)
 256                         return 0;
 257
 258                 log_error("Failed to open directory %s: %m", i->path);
 259                 return -errno;
 260         }
 261
 262         if (fstat(dirfd(d), &s) < 0) {
 263                 log_error("stat(%s) failed: %m", i->path);
 264                 r = -errno;
 265                 goto finish;
 266         }
 267
 268         if (!S_ISDIR(s.st_mode)) {
 269                 log_error("%s is not a directory.", i->path);
 270                 r = -ENOTDIR;
 271                 goto finish;
 272         }
 273
 274         if (fstatat(dirfd(d), "..", &ps, AT_SYMLINK_NOFOLLOW) != 0) {
 275                 log_error("stat(%s/..) failed: %m", i->path);
 276                 r = -errno;
 277                 goto finish;
 278         }
 279
 280         mountpoint = s.st_dev != ps.st_dev ||
 281                      (s.st_dev == ps.st_dev && s.st_ino == ps.st_ino);
 282
 283         r = dir_cleanup(i->path, d, &s, cutoff, s.st_dev, mountpoint, MAX_DEPTH);
 284
 285 finish:
 286         if (d)
 287                 closedir(d);
 288
 289         return r;
 290 }
 291
 292 static int create_item(Item *i) {
 293         int fd = -1, r;
 294         mode_t u;
 295         struct stat st;
 296
 297         assert(i);
 298
 299         switch (i->type) {
 300
 301         case IGNORE_PATH:
 302         case REMOVE_PATH:
 303         case RECURSIVE_REMOVE_PATH:
 304                 return 0;
 305
 306         case CREATE_FILE:
 307         case TRUNCATE_FILE:
 308
 309                 u = umask(0);
 310                 fd = open(i->path, O_CREAT|O_NDELAY|O_CLOEXEC|O_WRONLY|O_NOCTTY|O_NOFOLLOW|
 311                           (i->type == TRUNCATE_FILE ? O_TRUNC : 0), i->mode);
 312                 umask(u);
 313
 314                 if (fd < 0) {
 315                         log_error("Failed to create file %s: %m", i->path);
 316                         r = -errno;
 317                         goto finish;
 318                 }
 319
 320                 if (fstat(fd, &st) < 0) {
 321                         log_error("stat(%s) failed: %m", i->path);
 322                         r = -errno;
 323                         goto finish;
 324                 }
 325
 326                 if (!S_ISREG(st.st_mode)) {
 327                         log_error("%s is not a file.", i->path);
 328                         r = -EEXIST;
 329                         goto finish;
 330                 }
 331
 332                 if (i->mode_set)
 333                         if (fchmod(fd, i->mode) < 0) {
 334                                 log_error("chmod(%s) failed: %m", i->path);
 335                                 r = -errno;
 336                                 goto finish;
 337                         }
 338
 339                 if (i->uid_set || i->gid_set)
 340                         if (fchown(fd,
 341                                    i->uid_set ? i->uid : (uid_t) -1,
 342                                    i->gid_set ? i->gid : (gid_t) -1) < 0) {
 343                                 log_error("chown(%s) failed: %m", i->path);
 344                                 r = -errno;
 345                                 goto finish;
 346                         }
 347
 348                 break;
 349
 350         case TRUNCATE_DIRECTORY:
 351         case CREATE_DIRECTORY:
 352
 353                 u = umask(0);
 354                 r = mkdir(i->path, i->mode);
 355                 umask(u);
 356
 357                 if (r < 0 && errno != EEXIST) {
 358                         log_error("Failed to create directory %s: %m", i->path);
 359                         r = -errno;
 360                         goto finish;
 361                 }
 362
 363                 if (stat(i->path, &st) < 0) {
 364                         log_error("stat(%s) failed: %m", i->path);
 365                         r = -errno;
 366                         goto finish;
 367                 }
 368
 369                 if (!S_ISDIR(st.st_mode)) {
 370                         log_error("%s is not a directory.", i->path);
 371                         r = -EEXIST;
 372                         goto finish;
 373                 }
 374
 375                 if (i->mode_set)
 376                         if (chmod(i->path, i->mode) < 0) {
 377                                 log_error("chmod(%s) failed: %m", i->path);
 378                                 r = -errno;
 379                                 goto finish;
 380                         }
 381
 382                 if (i->uid_set || i->gid_set)
 383                         if (chown(i->path,
 384                                   i->uid_set ? i->uid : (uid_t) -1,
 385                                   i->gid_set ? i->gid : (gid_t) -1) < 0) {
 386
 387                                 log_error("chown(%s) failed: %m", i->path);
 388                                 r = -errno;
 389                                 goto finish;
 390                         }
 391
 392                 break;
 393         }
 394
 395         if ((r = label_fix(i->path)) < 0)
 396                 goto finish;
 397
 398         log_debug("%s created successfully.", i->path);
 399
 400 finish:
 401         if (fd >= 0)
 402                 close_nointr_nofail(fd);
 403
 404         return r;
 405 }
 406
 407 static int remove_item(Item *i) {
 408         int r;
 409
 410         assert(i);
 411
 412         switch (i->type) {
 413
 414         case CREATE_FILE:
 415         case TRUNCATE_FILE:
 416         case CREATE_DIRECTORY:
 417         case IGNORE_PATH:
 418                 break;
 419
 420         case REMOVE_PATH:
 421                 if (remove(i->path) < 0 && errno != ENOENT) {
 422                         log_error("remove(%s): %m", i->path);
 423                         return -errno;
 424                 }
 425
 426                 break;
 427
 428         case TRUNCATE_DIRECTORY:
 429         case RECURSIVE_REMOVE_PATH:
 430                 if ((r = rm_rf(i->path, false, i->type == RECURSIVE_REMOVE_PATH)) < 0 &&
 431                     r != -ENOENT) {
 432                         log_error("rm_rf(%s): %s", i->path, strerror(-r));
 433                         return r;
 434                 }
 435
 436                 break;
 437         }
 438
 439         return 0;
 440 }
 441
 442 static int process_item(Item *i) {
 443         int r, q, p;
 444
 445         assert(i);
 446
 447         r = arg_create ? create_item(i) : 0;
 448         q = arg_remove ? remove_item(i) : 0;
 449         p = arg_clean ? clean_item(i) : 0;
 450
 451         if (r < 0)
 452                 return r;
 453
 454         if (q < 0)
 455                 return q;
 456
 457         return p;
 458 }
 459
 460 static void item_free(Item *i) {
 461         assert(i);
 462
 463         free(i->path);
 464         free(i);
 465 }
 466
 467 static int parse_line(const char *fname, unsigned line, const char *buffer, const char *prefix) {
 468         Item *i;
 469         char *mode = NULL, *user = NULL, *group = NULL, *age = NULL;
 470         int r, n;
 471
 472         assert(fname);
 473         assert(line >= 1);
 474         assert(buffer);
 475
 476         if (!(i = new0(Item, 1))) {
 477                 log_error("Out of memory");
 478                 return -ENOMEM;
 479         }
 480
 481         if ((n = sscanf(buffer,
 482                         "%c "
 483                         "%ms "
 484                         "%ms "
 485                         "%ms "
 486                         "%ms "
 487                         "%ms",
 488                         &i->type,
 489                         &i->path,
 490                         &mode,
 491                         &user,
 492                         &group,
 493                         &age)) < 2) {
 494                 log_error("[%s:%u] Syntax error.", fname, line);
 495                 r = -EIO;
 496                 goto finish;
 497         }
 498
 499         if (i->type != CREATE_FILE &&
 500             i->type != CREATE_DIRECTORY &&
 501             i->type != TRUNCATE_FILE &&
 502             i->type != IGNORE_PATH &&
 503             i->type != REMOVE_PATH &&
 504             i->type != RECURSIVE_REMOVE_PATH) {
 505                 log_error("[%s:%u] Unknown file type '%c'.", fname, line, i->type);
 506                 r = -EBADMSG;
 507                 goto finish;
 508         }
 509
 510         if (!path_is_absolute(i->path)) {
 511                 log_error("[%s:%u] Path '%s' not absolute.", fname, line, i->path);
 512                 r = -EBADMSG;
 513                 goto finish;
 514         }
 515
 516         path_kill_slashes(i->path);
 517
 518         if (prefix && !path_startswith(i->path, prefix)) {
 519                 r = 0;
 520                 goto finish;
 521         }
 522
 523         if (user && !streq(user, "-")) {
 524                 unsigned long lu;
 525                 struct passwd *p;
 526
 527                 if (streq(user, "root") || streq(user, "0"))
 528                         i->uid = 0;
 529                 else if (safe_atolu(user, &lu) >= 0)
 530                         i->uid = (uid_t) lu;
 531                 else if ((p = getpwnam(user)))
 532                         i->uid = p->pw_uid;
 533                 else {
 534                         log_error("[%s:%u] Unknown user '%s'.", fname, line, user);
 535                         r = -ENOENT;
 536                         goto finish;
 537                 }
 538
 539                 i->uid_set = true;
 540         }
 541
 542         if (group && !streq(group, "-")) {
 543                 unsigned long lu;
 544                 struct group *g;
 545
 546                 if (streq(group, "root") || streq(group, "0"))
 547                         i->gid = 0;
 548                 else if (safe_atolu(group, &lu) >= 0)
 549                         i->gid = (gid_t) lu;
 550                 else if ((g = getgrnam(group)))
 551                         i->gid = g->gr_gid;
 552                 else {
 553                         log_error("[%s:%u] Unknown group '%s'.", fname, line, group);
 554                         r = -ENOENT;
 555                         goto finish;
 556                 }
 557
 558                 i->gid_set = true;
 559         }
 560
 561         if (mode && !streq(mode, "-")) {
 562                 unsigned m;
 563
 564                 if (sscanf(mode, "%o", &m) != 1) {
 565                         log_error("[%s:%u] Invalid mode '%s'.", fname, line, mode);
 566                         r = -ENOENT;
 567                         goto finish;
 568                 }
 569
 570                 i->mode = m;
 571                 i->mode_set = true;
 572         } else
 573                 i->mode = i->type == CREATE_DIRECTORY ? 0755 : 0644;
 574
 575         if (age && !streq(age, "-")) {
 576                 if (parse_usec(age, &i->age) < 0) {
 577                         log_error("[%s:%u] Invalid age '%s'.", fname, line, age);
 578                         r = -EBADMSG;
 579                         goto finish;
 580                 }
 581
 582                 i->age_set = true;
 583         }
 584
 585         if ((r = hashmap_put(items, i->path, i)) < 0) {
 586                 log_error("Failed to insert item %s: %s", i->path, strerror(-r));
 587                 goto finish;
 588         }
 589
 590         i = NULL;
 591         r = 0;
 592
 593 finish:
 594         free(user);
 595         free(group);
 596         free(mode);
 597         free(age);
 598
 599         if (i)
 600                 item_free(i);
 601
 602         return r;
 603 }
 604
 605 static int scandir_filter(const struct dirent *d) {
 606         assert(d);
 607
 608         if (ignore_file(d->d_name))
 609                 return 0;
 610
 611         if (d->d_type != DT_REG &&
 612             d->d_type != DT_LNK)
 613                 return 0;
 614
 615         return endswith(d->d_name, ".conf");
 616 }
 617
 618 static int help(void) {
 619
 620         printf("%s [OPTIONS...]\n\n"
 621                "Create and clean up temporary directories.\n\n"
 622                "  -h --help             Show this help\n"
 623                "     --create           Create marked files/directories\n"
 624                "     --clean            Clean up marked directories\n"
 625                "     --remove           Remove marked files/directories\n",
 626                program_invocation_short_name);
 627
 628         return 0;
 629 }
 630
 631 static int parse_argv(int argc, char *argv[]) {
 632
 633         enum {
 634                 ARG_CREATE,
 635                 ARG_CLEAN,
 636                 ARG_REMOVE
 637         };
 638
 639         static const struct option options[] = {
 640                 { "help",      no_argument,       NULL, 'h'           },
 641                 { "create",    no_argument,       NULL, ARG_CREATE    },
 642                 { "clean",     no_argument,       NULL, ARG_CLEAN     },
 643                 { "remove",    no_argument,       NULL, ARG_REMOVE    },
 644                 { NULL,        0,                 NULL, 0             }
 645         };
 646
 647         int c;
 648
 649         assert(argc >= 0);
 650         assert(argv);
 651
 652         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0) {
 653
 654                 switch (c) {
 655
 656                 case 'h':
 657                         help();
 658                         return 0;
 659
 660                 case ARG_CREATE:
 661                         arg_create = true;
 662                         break;
 663
 664                 case ARG_CLEAN:
 665                         arg_clean = true;
 666                         break;
 667
 668                 case ARG_REMOVE:
 669                         arg_remove = true;
 670                         break;
 671
 672                 case '?':
 673                         return -EINVAL;
 674
 675                 default:
 676                         log_error("Unknown option code %c", c);
 677                         return -EINVAL;
 678                 }
 679         }
 680
 681         if (!arg_clean && !arg_create && !arg_remove) {
 682                 help();
 683                 return -EINVAL;
 684         }
 685
 686         return 1;
 687 }
 688
 689 int main(int argc, char *argv[]) {
 690         struct dirent **de = NULL;
 691         int r, n, j;
 692         const char *prefix = NULL;
 693         Item *i;
 694         Iterator iterator;
 695
 696         if ((r = parse_argv(argc, argv)) <= 0)
 697                 return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
 698
 699         if (optind < argc)
 700                 prefix = argv[optind];
 701         else
 702                 prefix = "/";
 703
 704         log_set_target(LOG_TARGET_SYSLOG_OR_KMSG);
 705         log_parse_environment();
 706         log_open();
 707
 708         label_init();
 709
 710         if (!(items = hashmap_new(string_hash_func, string_compare_func))) {
 711                 log_error("Out of memory");
 712                 r = EXIT_FAILURE;
 713                 goto finish;
 714         }
 715
 716         if ((n = scandir("/etc/tmpfiles.d/", &de, scandir_filter, alphasort)) < 0) {
 717
 718                 if (errno == ENOENT)
 719                         r = EXIT_SUCCESS;
 720                 else {
 721                         log_error("Failed to enumerate /etc/tmpfiles.d/ files: %m");
 722                         r = EXIT_FAILURE;
 723                 }
 724
 725                 goto finish;
 726         }
 727
 728         r = EXIT_SUCCESS;
 729
 730         for (j = 0; j < n; j++) {
 731                 int k;
 732                 char *fn;
 733                 FILE *f;
 734                 unsigned v;
 735
 736                 k = asprintf(&fn, "/etc/tmpfiles.d/%s", de[j]->d_name);
 737                 free(de[j]);
 738
 739                 if (k < 0) {
 740                         log_error("Failed to allocate file name.");
 741                         r = EXIT_FAILURE;
 742                         continue;
 743                 }
 744
 745                 if (!(f = fopen(fn, "re"))) {
 746
 747                         if (errno != ENOENT) {
 748                                 log_error("Failed to open %s: %m", fn);
 749                                 r = EXIT_FAILURE;
 750                         }
 751
 752                         free(fn);
 753                         continue;
 754                 }
 755
 756                 v = 0;
 757                 for (;;) {
 758                         char line[LINE_MAX], *l;
 759
 760                         if (!(fgets(line, sizeof(line), f)))
 761                                 break;
 762
 763                         v++;
 764
 765                         l = strstrip(line);
 766                         if (*l == '#' || *l == 0)
 767                                 continue;
 768
 769                         if (parse_line(fn, v, l, prefix) < 0)
 770                                 r = EXIT_FAILURE;
 771                 }
 772
 773                 if (ferror(f)) {
 774                         r = EXIT_FAILURE;
 775                         log_error("Failed to read from file %s: %m", fn);
 776                 }
 777
 778                 free(fn);
 779
 780                 fclose(f);
 781         }
 782
 783         free(de);
 784
 785         HASHMAP_FOREACH(i, items, iterator)
 786                 if (process_item(i) < 0)
 787                         r = EXIT_FAILURE;
 788
 789 finish:
 790         while ((i = hashmap_steal_first(items)))
 791                 item_free(i);
 792
 793         hashmap_free(items);
 794
 795         label_finish();
 796
 797         return r;
 798 }