src/libsystemd/sd-path/sd-path.c

   1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
   2
   3 #include "sd-path.h"
   4
   5 #include "alloc-util.h"
   6 #include "architecture.h"
   7 #include "fd-util.h"
   8 #include "fileio.h"
   9 #include "fs-util.h"
  10 #include "path-lookup.h"
  11 #include "path-util.h"
  12 #include "string-util.h"
  13 #include "strv.h"
  14 #include "user-util.h"
  15 #include "util.h"
  16
  17 static int from_environment(const char *envname, const char *fallback, const char **ret) {
  18         assert(ret);
  19
  20         if (envname) {
  21                 const char *e;
  22
  23                 e = secure_getenv(envname);
  24                 if (e && path_is_absolute(e)) {
  25                         *ret = e;
  26                         return 0;
  27                 }
  28         }
  29
  30         if (fallback) {
  31                 *ret = fallback;
  32                 return 0;
  33         }
  34
  35         return -ENXIO;
  36 }
  37
  38 static int from_home_dir(const char *envname, const char *suffix, char **buffer, const char **ret) {
  39         _cleanup_free_ char *h = NULL;
  40         char *cc = NULL;
  41         int r;
  42
  43         assert(suffix);
  44         assert(buffer);
  45         assert(ret);
  46
  47         if (envname) {
  48                 const char *e = NULL;
  49
  50                 e = secure_getenv(envname);
  51                 if (e && path_is_absolute(e)) {
  52                         *ret = e;
  53                         return 0;
  54                 }
  55         }
  56
  57         r = get_home_dir(&h);
  58         if (r < 0)
  59                 return r;
  60
  61         cc = path_join(h, suffix);
  62         if (!cc)
  63                 return -ENOMEM;
  64
  65         *buffer = cc;
  66         *ret = cc;
  67         return 0;
  68 }
  69
  70 static int from_user_dir(const char *field, char **buffer, const char **ret) {
  71         _cleanup_fclose_ FILE *f = NULL;
  72         _cleanup_free_ char *b = NULL;
  73         _cleanup_free_ const char *fn = NULL;
  74         const char *c = NULL;
  75         size_t n;
  76         int r;
  77
  78         assert(field);
  79         assert(buffer);
  80         assert(ret);
  81
  82         r = from_home_dir("XDG_CONFIG_HOME", ".config", &b, &c);
  83         if (r < 0)
  84                 return r;
  85
  86         fn = path_join(c, "user-dirs.dirs");
  87         if (!fn)
  88                 return -ENOMEM;
  89
  90         f = fopen(fn, "re");
  91         if (!f) {
  92                 if (errno == ENOENT)
  93                         goto fallback;
  94
  95                 return -errno;
  96         }
  97
  98         /* This is an awful parse, but it follows closely what
  99          * xdg-user-dirs does upstream */
 100
 101         n = strlen(field);
 102         for (;;) {
 103                 _cleanup_free_ char *line = NULL;
 104                 char *l, *p, *e;
 105
 106                 r = read_line(f, LONG_LINE_MAX, &line);
 107                 if (r < 0)
 108                         return r;
 109                 if (r == 0)
 110                         break;
 111
 112                 l = strstrip(line);
 113
 114                 if (!strneq(l, field, n))
 115                         continue;
 116
 117                 p = l + n;
 118                 p += strspn(p, WHITESPACE);
 119
 120                 if (*p != '=')
 121                         continue;
 122                 p++;
 123
 124                 p += strspn(p, WHITESPACE);
 125
 126                 if (*p != '"')
 127                         continue;
 128                 p++;
 129
 130                 e = strrchr(p, '"');
 131                 if (!e)
 132                         continue;
 133                 *e = 0;
 134
 135                 /* Three syntaxes permitted: relative to $HOME, $HOME itself, and absolute path */
 136                 if (startswith(p, "$HOME/")) {
 137                         _cleanup_free_ char *h = NULL;
 138                         char *cc;
 139
 140                         r = get_home_dir(&h);
 141                         if (r < 0)
 142                                 return r;
 143
 144                         cc = path_join(h, p+5);
 145                         if (!cc)
 146                                 return -ENOMEM;
 147
 148                         *buffer = cc;
 149                         *ret = cc;
 150                         return 0;
 151                 } else if (streq(p, "$HOME")) {
 152
 153                         r = get_home_dir(buffer);
 154                         if (r < 0)
 155                                 return r;
 156
 157                         *ret = *buffer;
 158                         return 0;
 159                 } else if (path_is_absolute(p)) {
 160                         char *copy;
 161
 162                         copy = strdup(p);
 163                         if (!copy)
 164                                 return -ENOMEM;
 165
 166                         *buffer = copy;
 167                         *ret = copy;
 168                         return 0;
 169                 }
 170         }
 171
 172 fallback:
 173         /* The desktop directory defaults to $HOME/Desktop, the others to $HOME */
 174         if (streq(field, "XDG_DESKTOP_DIR")) {
 175                 _cleanup_free_ char *h = NULL;
 176                 char *cc;
 177
 178                 r = get_home_dir(&h);
 179                 if (r < 0)
 180                         return r;
 181
 182                 cc = path_join(h, "Desktop");
 183                 if (!cc)
 184                         return -ENOMEM;
 185
 186                 *buffer = cc;
 187                 *ret = cc;
 188         } else {
 189
 190                 r = get_home_dir(buffer);
 191                 if (r < 0)
 192                         return r;
 193
 194                 *ret = *buffer;
 195         }
 196
 197         return 0;
 198 }
 199
 200 static int get_path(uint64_t type, char **buffer, const char **ret) {
 201         int r;
 202
 203         assert(buffer);
 204         assert(ret);
 205
 206         switch (type) {
 207
 208         case SD_PATH_TEMPORARY:
 209                 return tmp_dir(ret);
 210
 211         case SD_PATH_TEMPORARY_LARGE:
 212                 return var_tmp_dir(ret);
 213
 214         case SD_PATH_SYSTEM_BINARIES:
 215                 *ret = "/usr/bin";
 216                 return 0;
 217
 218         case SD_PATH_SYSTEM_INCLUDE:
 219                 *ret = "/usr/include";
 220                 return 0;
 221
 222         case SD_PATH_SYSTEM_LIBRARY_PRIVATE:
 223                 *ret = "/usr/lib";
 224                 return 0;
 225
 226         case SD_PATH_SYSTEM_LIBRARY_ARCH:
 227                 *ret = LIBDIR;
 228                 return 0;
 229
 230         case SD_PATH_SYSTEM_SHARED:
 231                 *ret = "/usr/share";
 232                 return 0;
 233
 234         case SD_PATH_SYSTEM_CONFIGURATION_FACTORY:
 235                 *ret = "/usr/share/factory/etc";
 236                 return 0;
 237
 238         case SD_PATH_SYSTEM_STATE_FACTORY:
 239                 *ret = "/usr/share/factory/var";
 240                 return 0;
 241
 242         case SD_PATH_SYSTEM_CONFIGURATION:
 243                 *ret = "/etc";
 244                 return 0;
 245
 246         case SD_PATH_SYSTEM_RUNTIME:
 247                 *ret = "/run";
 248                 return 0;
 249
 250         case SD_PATH_SYSTEM_RUNTIME_LOGS:
 251                 *ret = "/run/log";
 252                 return 0;
 253
 254         case SD_PATH_SYSTEM_STATE_PRIVATE:
 255                 *ret = "/var/lib";
 256                 return 0;
 257
 258         case SD_PATH_SYSTEM_STATE_LOGS:
 259                 *ret = "/var/log";
 260                 return 0;
 261
 262         case SD_PATH_SYSTEM_STATE_CACHE:
 263                 *ret = "/var/cache";
 264                 return 0;
 265
 266         case SD_PATH_SYSTEM_STATE_SPOOL:
 267                 *ret = "/var/spool";
 268                 return 0;
 269
 270         case SD_PATH_USER_BINARIES:
 271                 return from_home_dir(NULL, ".local/bin", buffer, ret);
 272
 273         case SD_PATH_USER_LIBRARY_PRIVATE:
 274                 return from_home_dir(NULL, ".local/lib", buffer, ret);
 275
 276         case SD_PATH_USER_LIBRARY_ARCH:
 277                 return from_home_dir(NULL, ".local/lib/" LIB_ARCH_TUPLE, buffer, ret);
 278
 279         case SD_PATH_USER_SHARED:
 280                 return from_home_dir("XDG_DATA_HOME", ".local/share", buffer, ret);
 281
 282         case SD_PATH_USER_CONFIGURATION:
 283                 return from_home_dir("XDG_CONFIG_HOME", ".config", buffer, ret);
 284
 285         case SD_PATH_USER_RUNTIME:
 286                 return from_environment("XDG_RUNTIME_DIR", NULL, ret);
 287
 288         case SD_PATH_USER_STATE_CACHE:
 289                 return from_home_dir("XDG_CACHE_HOME", ".cache", buffer, ret);
 290
 291         case SD_PATH_USER:
 292                 r = get_home_dir(buffer);
 293                 if (r < 0)
 294                         return r;
 295
 296                 *ret = *buffer;
 297                 return 0;
 298
 299         case SD_PATH_USER_DOCUMENTS:
 300                 return from_user_dir("XDG_DOCUMENTS_DIR", buffer, ret);
 301
 302         case SD_PATH_USER_MUSIC:
 303                 return from_user_dir("XDG_MUSIC_DIR", buffer, ret);
 304
 305         case SD_PATH_USER_PICTURES:
 306                 return from_user_dir("XDG_PICTURES_DIR", buffer, ret);
 307
 308         case SD_PATH_USER_VIDEOS:
 309                 return from_user_dir("XDG_VIDEOS_DIR", buffer, ret);
 310
 311         case SD_PATH_USER_DOWNLOAD:
 312                 return from_user_dir("XDG_DOWNLOAD_DIR", buffer, ret);
 313
 314         case SD_PATH_USER_PUBLIC:
 315                 return from_user_dir("XDG_PUBLICSHARE_DIR", buffer, ret);
 316
 317         case SD_PATH_USER_TEMPLATES:
 318                 return from_user_dir("XDG_TEMPLATES_DIR", buffer, ret);
 319
 320         case SD_PATH_USER_DESKTOP:
 321                 return from_user_dir("XDG_DESKTOP_DIR", buffer, ret);
 322
 323         case SD_PATH_SYSTEMD_UTIL:
 324                 *ret = ROOTPREFIX_NOSLASH "/lib/systemd";
 325                 return 0;
 326
 327         case SD_PATH_SYSTEMD_SYSTEM_UNIT:
 328                 *ret = SYSTEM_DATA_UNIT_PATH;
 329                 return 0;
 330
 331         case SD_PATH_SYSTEMD_SYSTEM_PRESET:
 332                 *ret = ROOTPREFIX_NOSLASH "/lib/systemd/system-preset";
 333                 return 0;
 334
 335         case SD_PATH_SYSTEMD_USER_UNIT:
 336                 *ret = USER_DATA_UNIT_DIR;
 337                 return 0;
 338
 339         case SD_PATH_SYSTEMD_USER_PRESET:
 340                 *ret = ROOTPREFIX_NOSLASH "/lib/systemd/user-preset";
 341                 return 0;
 342
 343         case SD_PATH_SYSTEMD_SYSTEM_CONF:
 344                 *ret = SYSTEM_CONFIG_UNIT_DIR;
 345                 return 0;
 346
 347         case SD_PATH_SYSTEMD_USER_CONF:
 348                 *ret = USER_CONFIG_UNIT_DIR;
 349                 return 0;
 350
 351         case SD_PATH_SYSTEMD_SYSTEM_GENERATOR:
 352                 *ret = SYSTEM_GENERATOR_DIR;
 353                 return 0;
 354
 355         case SD_PATH_SYSTEMD_USER_GENERATOR:
 356                 *ret = USER_GENERATOR_DIR;
 357                 return 0;
 358
 359         case SD_PATH_SYSTEMD_SLEEP:
 360                 *ret = ROOTPREFIX_NOSLASH "/lib/systemd/system-sleep";
 361                 return 0;
 362
 363         case SD_PATH_SYSTEMD_SHUTDOWN:
 364                 *ret = ROOTPREFIX_NOSLASH "/lib/systemd/system-shutdown";
 365                 return 0;
 366
 367         case SD_PATH_TMPFILES:
 368                 *ret = "/usr/lib/tmpfiles.d";
 369                 return 0;
 370
 371         case SD_PATH_SYSUSERS:
 372                 *ret = ROOTPREFIX_NOSLASH "/lib/sysusers.d";
 373                 return 0;
 374
 375         case SD_PATH_SYSCTL:
 376                 *ret = ROOTPREFIX_NOSLASH "/lib/sysctl.d";
 377                 return 0;
 378
 379         case SD_PATH_BINFMT:
 380                 *ret = ROOTPREFIX_NOSLASH "/lib/binfmt.d";
 381                 return 0;
 382
 383         case SD_PATH_MODULES_LOAD:
 384                 *ret = ROOTPREFIX_NOSLASH "/lib/modules-load.d";
 385                 return 0;
 386
 387         case SD_PATH_CATALOG:
 388                 *ret = "/usr/lib/systemd/catalog";
 389                 return 0;
 390         }
 391
 392         return -EOPNOTSUPP;
 393 }
 394
 395 static int get_path_alloc(uint64_t type, const char *suffix, char **path) {
 396         _cleanup_free_ char *buffer = NULL;
 397         char *buffer2 = NULL;
 398         const char *ret;
 399         int r;
 400
 401         assert(path);
 402
 403         r = get_path(type, &buffer, &ret);
 404         if (r < 0)
 405                 return r;
 406
 407         if (suffix) {
 408                 suffix += strspn(suffix, "/");
 409                 buffer2 = path_join(ret, suffix);
 410                 if (!buffer2)
 411                         return -ENOMEM;
 412         } else if (!buffer) {
 413                 buffer = strdup(ret);
 414                 if (!buffer)
 415                         return -ENOMEM;
 416         }
 417
 418         *path = buffer2 ?: TAKE_PTR(buffer);
 419         return 0;
 420 }
 421
 422 _public_ int sd_path_lookup(uint64_t type, const char *suffix, char **path) {
 423         int r;
 424
 425         assert_return(path, -EINVAL);
 426
 427         r = get_path_alloc(type, suffix, path);
 428         if (r != -EOPNOTSUPP)
 429                 return r;
 430
 431         /* Fall back to sd_path_lookup_strv */
 432         _cleanup_strv_free_ char **l = NULL;
 433         char *buffer;
 434
 435         r = sd_path_lookup_strv(type, suffix, &l);
 436         if (r < 0)
 437                 return r;
 438
 439         buffer = strv_join(l, ":");
 440         if (!buffer)
 441                 return -ENOMEM;
 442
 443         *path = buffer;
 444         return 0;
 445 }
 446
 447 static int search_from_environment(
 448                 char ***list,
 449                 const char *env_home,
 450                 const char *home_suffix,
 451                 const char *env_search,
 452                 bool env_search_sufficient,
 453                 const char *first, ...) {
 454
 455         _cleanup_strv_free_ char **l = NULL;
 456         const char *e;
 457         char *h = NULL;
 458         int r;
 459
 460         assert(list);
 461
 462         if (env_search) {
 463                 e = secure_getenv(env_search);
 464                 if (e) {
 465                         l = strv_split(e, ":");
 466                         if (!l)
 467                                 return -ENOMEM;
 468
 469                         if (env_search_sufficient) {
 470                                 *list = TAKE_PTR(l);
 471                                 return 0;
 472                         }
 473                 }
 474         }
 475
 476         if (!l && first) {
 477                 va_list ap;
 478
 479                 va_start(ap, first);
 480                 l = strv_new_ap(first, ap);
 481                 va_end(ap);
 482
 483                 if (!l)
 484                         return -ENOMEM;
 485         }
 486
 487         if (env_home) {
 488                 e = secure_getenv(env_home);
 489                 if (e && path_is_absolute(e)) {
 490                         h = strdup(e);
 491                         if (!h)
 492                                 return -ENOMEM;
 493                 }
 494         }
 495
 496         if (!h && home_suffix) {
 497                 e = secure_getenv("HOME");
 498                 if (e && path_is_absolute(e)) {
 499                         h = path_join(e, home_suffix);
 500                         if (!h)
 501                                 return -ENOMEM;
 502                 }
 503         }
 504
 505         if (h) {
 506                 r = strv_consume_prepend(&l, h);
 507                 if (r < 0)
 508                         return -ENOMEM;
 509         }
 510
 511         *list = TAKE_PTR(l);
 512         return 0;
 513 }
 514
 515 #if HAVE_SPLIT_BIN
 516 #  define ARRAY_SBIN_BIN(x) x "sbin", x "bin"
 517 #else
 518 #  define ARRAY_SBIN_BIN(x) x "bin"
 519 #endif
 520
 521 static int get_search(uint64_t type, char ***list) {
 522         int r;
 523
 524         assert(list);
 525
 526         switch(type) {
 527
 528         case SD_PATH_SEARCH_BINARIES:
 529                 return search_from_environment(list,
 530                                                NULL,
 531                                                ".local/bin",
 532                                                "PATH",
 533                                                true,
 534                                                ARRAY_SBIN_BIN("/usr/local/"),
 535                                                ARRAY_SBIN_BIN("/usr/"),
 536 #if HAVE_SPLIT_USR
 537                                                ARRAY_SBIN_BIN("/"),
 538 #endif
 539                                                NULL);
 540
 541         case SD_PATH_SEARCH_LIBRARY_PRIVATE:
 542                 return search_from_environment(list,
 543                                                NULL,
 544                                                ".local/lib",
 545                                                NULL,
 546                                                false,
 547                                                "/usr/local/lib",
 548                                                "/usr/lib",
 549 #if HAVE_SPLIT_USR
 550                                                "/lib",
 551 #endif
 552                                                NULL);
 553
 554         case SD_PATH_SEARCH_LIBRARY_ARCH:
 555                 return search_from_environment(list,
 556                                                NULL,
 557                                                ".local/lib/" LIB_ARCH_TUPLE,
 558                                                "LD_LIBRARY_PATH",
 559                                                true,
 560                                                LIBDIR,
 561 #if HAVE_SPLIT_USR
 562                                                ROOTLIBDIR,
 563 #endif
 564                                                NULL);
 565
 566         case SD_PATH_SEARCH_SHARED:
 567                 return search_from_environment(list,
 568                                                "XDG_DATA_HOME",
 569                                                ".local/share",
 570                                                "XDG_DATA_DIRS",
 571                                                false,
 572                                                "/usr/local/share",
 573                                                "/usr/share",
 574                                                NULL);
 575
 576         case SD_PATH_SEARCH_CONFIGURATION_FACTORY:
 577                 return search_from_environment(list,
 578                                                NULL,
 579                                                NULL,
 580                                                NULL,
 581                                                false,
 582                                                "/usr/local/share/factory/etc",
 583                                                "/usr/share/factory/etc",
 584                                                NULL);
 585
 586         case SD_PATH_SEARCH_STATE_FACTORY:
 587                 return search_from_environment(list,
 588                                                NULL,
 589                                                NULL,
 590                                                NULL,
 591                                                false,
 592                                                "/usr/local/share/factory/var",
 593                                                "/usr/share/factory/var",
 594                                                NULL);
 595
 596         case SD_PATH_SEARCH_CONFIGURATION:
 597                 return search_from_environment(list,
 598                                                "XDG_CONFIG_HOME",
 599                                                ".config",
 600                                                "XDG_CONFIG_DIRS",
 601                                                false,
 602                                                "/etc",
 603                                                NULL);
 604
 605         case SD_PATH_SEARCH_BINARIES_DEFAULT:
 606                 return strv_from_nulstr(list, DEFAULT_PATH_NULSTR);
 607
 608         case SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT:
 609         case SD_PATH_SYSTEMD_SEARCH_USER_UNIT: {
 610                 _cleanup_(lookup_paths_free) LookupPaths lp = {};
 611                 const UnitFileScope scope = type == SD_PATH_SYSTEMD_SEARCH_SYSTEM_UNIT ?
 612                                                     UNIT_FILE_SYSTEM : UNIT_FILE_USER;
 613
 614                 r = lookup_paths_init(&lp, scope, 0, NULL);
 615                 if (r < 0)
 616                         return r;
 617
 618                 *list = TAKE_PTR(lp.search_path);
 619                 return 0;
 620         }
 621
 622         case SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR:
 623         case SD_PATH_SYSTEMD_SEARCH_USER_GENERATOR: {
 624                 char **t;
 625                 const UnitFileScope scope = type == SD_PATH_SYSTEMD_SEARCH_SYSTEM_GENERATOR ?
 626                                                     UNIT_FILE_SYSTEM : UNIT_FILE_USER;
 627
 628                 t = generator_binary_paths(scope);
 629                 if (!t)
 630                         return -ENOMEM;
 631
 632                 *list = t;
 633                 return 0;
 634         }
 635
 636         case SD_PATH_SYSTEMD_SEARCH_NETWORK:
 637                 return strv_from_nulstr(list, NETWORK_DIRS_NULSTR);
 638
 639         }
 640
 641         return -EOPNOTSUPP;
 642 }
 643
 644 _public_ int sd_path_lookup_strv(uint64_t type, const char *suffix, char ***paths) {
 645         _cleanup_strv_free_ char **l = NULL, **n = NULL;
 646         int r;
 647
 648         assert_return(paths, -EINVAL);
 649
 650         r = get_search(type, &l);
 651         if (r == -EOPNOTSUPP) {
 652                 _cleanup_free_ char *t = NULL;
 653
 654                 r = get_path_alloc(type, suffix, &t);
 655                 if (r < 0)
 656                         return r;
 657
 658                 l = new(char*, 2);
 659                 if (!l)
 660                         return -ENOMEM;
 661                 l[0] = TAKE_PTR(t);
 662                 l[1] = NULL;
 663
 664                 *paths = TAKE_PTR(l);
 665                 return 0;
 666
 667         } else if (r < 0)
 668                 return r;
 669
 670         if (!suffix) {
 671                 *paths = TAKE_PTR(l);
 672                 return 0;
 673         }
 674
 675         n = new(char*, strv_length(l)+1);
 676         if (!n)
 677                 return -ENOMEM;
 678
 679         char **i, **j = n;
 680         STRV_FOREACH(i, l) {
 681                 *j = path_join(*i, suffix);
 682                 if (!*j)
 683                         return -ENOMEM;
 684
 685                 j++;
 686         }
 687         *j = NULL;
 688
 689         *paths = TAKE_PTR(n);
 690         return 0;
 691 }