src/sysusers/sysusers.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <getopt.h>
   4 #include <utmp.h>
   5
   6 #include "alloc-util.h"
   7 #include "conf-files.h"
   8 #include "copy.h"
   9 #include "def.h"
  10 #include "fd-util.h"
  11 #include "fileio.h"
  12 #include "format-util.h"
  13 #include "fs-util.h"
  14 #include "hashmap.h"
  15 #include "main-func.h"
  16 #include "pager.h"
  17 #include "path-util.h"
  18 #include "pretty-print.h"
  19 #include "set.h"
  20 #include "selinux-util.h"
  21 #include "smack-util.h"
  22 #include "specifier.h"
  23 #include "string-util.h"
  24 #include "strv.h"
  25 #include "tmpfile-util-label.h"
  26 #include "uid-range.h"
  27 #include "user-util.h"
  28 #include "utf8.h"
  29 #include "util.h"
  30
  31 typedef enum ItemType {
  32         ADD_USER = 'u',
  33         ADD_GROUP = 'g',
  34         ADD_MEMBER = 'm',
  35         ADD_RANGE = 'r',
  36 } ItemType;
  37
  38 typedef struct Item {
  39         ItemType type;
  40
  41         char *name;
  42         char *uid_path;
  43         char *gid_path;
  44         char *description;
  45         char *home;
  46         char *shell;
  47
  48         gid_t gid;
  49         uid_t uid;
  50
  51         bool gid_set:1;
  52
  53         /* When set the group with the specified gid must exist
  54          * and the check if a uid clashes with the gid is skipped.
  55          */
  56         bool id_set_strict:1;
  57
  58         bool uid_set:1;
  59
  60         bool todo_user:1;
  61         bool todo_group:1;
  62 } Item;
  63
  64 static char *arg_root = NULL;
  65 static bool arg_cat_config = false;
  66 static const char *arg_replace = NULL;
  67 static bool arg_inline = false;
  68 static PagerFlags arg_pager_flags = 0;
  69
  70 static OrderedHashmap *users = NULL, *groups = NULL;
  71 static OrderedHashmap *todo_uids = NULL, *todo_gids = NULL;
  72 static OrderedHashmap *members = NULL;
  73
  74 static Hashmap *database_by_uid = NULL, *database_by_username = NULL;
  75 static Hashmap *database_by_gid = NULL, *database_by_groupname = NULL;
  76 static Set *database_users = NULL, *database_groups = NULL;
  77
  78 static uid_t search_uid = UID_INVALID;
  79 static UidRange *uid_range = NULL;
  80 static unsigned n_uid_range = 0;
  81
  82 STATIC_DESTRUCTOR_REGISTER(groups, ordered_hashmap_freep);
  83 STATIC_DESTRUCTOR_REGISTER(users, ordered_hashmap_freep);
  84 STATIC_DESTRUCTOR_REGISTER(members, ordered_hashmap_freep);
  85 STATIC_DESTRUCTOR_REGISTER(todo_uids, ordered_hashmap_freep);
  86 STATIC_DESTRUCTOR_REGISTER(todo_gids, ordered_hashmap_freep);
  87 STATIC_DESTRUCTOR_REGISTER(database_by_uid, hashmap_freep);
  88 STATIC_DESTRUCTOR_REGISTER(database_by_username, hashmap_freep);
  89 STATIC_DESTRUCTOR_REGISTER(database_users, set_free_freep);
  90 STATIC_DESTRUCTOR_REGISTER(database_by_gid, hashmap_freep);
  91 STATIC_DESTRUCTOR_REGISTER(database_by_groupname, hashmap_freep);
  92 STATIC_DESTRUCTOR_REGISTER(database_groups, set_free_freep);
  93 STATIC_DESTRUCTOR_REGISTER(uid_range, freep);
  94 STATIC_DESTRUCTOR_REGISTER(arg_root, freep);
  95
  96 static int load_user_database(void) {
  97         _cleanup_fclose_ FILE *f = NULL;
  98         const char *passwd_path;
  99         struct passwd *pw;
 100         int r;
 101
 102         passwd_path = prefix_roota(arg_root, "/etc/passwd");
 103         f = fopen(passwd_path, "re");
 104         if (!f)
 105                 return errno == ENOENT ? 0 : -errno;
 106
 107         r = hashmap_ensure_allocated(&database_by_username, &string_hash_ops);
 108         if (r < 0)
 109                 return r;
 110
 111         r = hashmap_ensure_allocated(&database_by_uid, NULL);
 112         if (r < 0)
 113                 return r;
 114
 115         r = set_ensure_allocated(&database_users, NULL);
 116         if (r < 0)
 117                 return r;
 118
 119         while ((r = fgetpwent_sane(f, &pw)) > 0) {
 120                 char *n;
 121                 int k, q;
 122
 123                 n = strdup(pw->pw_name);
 124                 if (!n)
 125                         return -ENOMEM;
 126
 127                 k = set_put(database_users, n);
 128                 if (k < 0) {
 129                         free(n);
 130                         return k;
 131                 }
 132
 133                 k = hashmap_put(database_by_username, n, UID_TO_PTR(pw->pw_uid));
 134                 if (k < 0 && k != -EEXIST)
 135                         return k;
 136
 137                 q = hashmap_put(database_by_uid, UID_TO_PTR(pw->pw_uid), n);
 138                 if (q < 0 && q != -EEXIST)
 139                         return q;
 140         }
 141         return r;
 142 }
 143
 144 static int load_group_database(void) {
 145         _cleanup_fclose_ FILE *f = NULL;
 146         const char *group_path;
 147         struct group *gr;
 148         int r;
 149
 150         group_path = prefix_roota(arg_root, "/etc/group");
 151         f = fopen(group_path, "re");
 152         if (!f)
 153                 return errno == ENOENT ? 0 : -errno;
 154
 155         r = hashmap_ensure_allocated(&database_by_groupname, &string_hash_ops);
 156         if (r < 0)
 157                 return r;
 158
 159         r = hashmap_ensure_allocated(&database_by_gid, NULL);
 160         if (r < 0)
 161                 return r;
 162
 163         r = set_ensure_allocated(&database_groups, NULL);
 164         if (r < 0)
 165                 return r;
 166
 167         while ((r = fgetgrent_sane(f, &gr)) > 0) {
 168                 char *n;
 169                 int k, q;
 170
 171                 n = strdup(gr->gr_name);
 172                 if (!n)
 173                         return -ENOMEM;
 174
 175                 k = set_put(database_groups, n);
 176                 if (k < 0) {
 177                         free(n);
 178                         return k;
 179                 }
 180
 181                 k = hashmap_put(database_by_groupname, n, GID_TO_PTR(gr->gr_gid));
 182                 if (k < 0 && k != -EEXIST)
 183                         return k;
 184
 185                 q = hashmap_put(database_by_gid, GID_TO_PTR(gr->gr_gid), n);
 186                 if (q < 0 && q != -EEXIST)
 187                         return q;
 188         }
 189         return r;
 190 }
 191
 192 static int make_backup(const char *target, const char *x) {
 193         _cleanup_close_ int src = -1;
 194         _cleanup_fclose_ FILE *dst = NULL;
 195         _cleanup_free_ char *temp = NULL;
 196         char *backup;
 197         struct timespec ts[2];
 198         struct stat st;
 199         int r;
 200
 201         src = open(x, O_RDONLY|O_CLOEXEC|O_NOCTTY);
 202         if (src < 0) {
 203                 if (errno == ENOENT) /* No backup necessary... */
 204                         return 0;
 205
 206                 return -errno;
 207         }
 208
 209         if (fstat(src, &st) < 0)
 210                 return -errno;
 211
 212         r = fopen_temporary_label(target, x, &dst, &temp);
 213         if (r < 0)
 214                 return r;
 215
 216         r = copy_bytes(src, fileno(dst), (uint64_t) -1, COPY_REFLINK);
 217         if (r < 0)
 218                 goto fail;
 219
 220         /* Don't fail on chmod() or chown(). If it stays owned by us
 221          * and/or unreadable by others, then it isn't too bad... */
 222
 223         backup = strjoina(x, "-");
 224
 225         /* Copy over the access mask */
 226         r = fchmod_and_chown(fileno(dst), st.st_mode & 07777, st.st_uid, st.st_gid);
 227         if (r < 0)
 228                 log_warning_errno(r, "Failed to change access mode or ownership of %s: %m", backup);
 229
 230         ts[0] = st.st_atim;
 231         ts[1] = st.st_mtim;
 232         if (futimens(fileno(dst), ts) < 0)
 233                 log_warning_errno(errno, "Failed to fix access and modification time of %s: %m", backup);
 234
 235         r = fflush_sync_and_check(dst);
 236         if (r < 0)
 237                 goto fail;
 238
 239         if (rename(temp, backup) < 0) {
 240                 r = -errno;
 241                 goto fail;
 242         }
 243
 244         return 0;
 245
 246 fail:
 247         unlink(temp);
 248         return r;
 249 }
 250
 251 static int putgrent_with_members(const struct group *gr, FILE *group) {
 252         char **a;
 253
 254         assert(gr);
 255         assert(group);
 256
 257         a = ordered_hashmap_get(members, gr->gr_name);
 258         if (a) {
 259                 _cleanup_strv_free_ char **l = NULL;
 260                 bool added = false;
 261                 char **i;
 262
 263                 l = strv_copy(gr->gr_mem);
 264                 if (!l)
 265                         return -ENOMEM;
 266
 267                 STRV_FOREACH(i, a) {
 268                         if (strv_find(l, *i))
 269                                 continue;
 270
 271                         if (strv_extend(&l, *i) < 0)
 272                                 return -ENOMEM;
 273
 274                         added = true;
 275                 }
 276
 277                 if (added) {
 278                         struct group t;
 279                         int r;
 280
 281                         strv_uniq(l);
 282                         strv_sort(l);
 283
 284                         t = *gr;
 285                         t.gr_mem = l;
 286
 287                         r = putgrent_sane(&t, group);
 288                         return r < 0 ? r : 1;
 289                 }
 290         }
 291
 292         return putgrent_sane(gr, group);
 293 }
 294
 295 #if ENABLE_GSHADOW
 296 static int putsgent_with_members(const struct sgrp *sg, FILE *gshadow) {
 297         char **a;
 298
 299         assert(sg);
 300         assert(gshadow);
 301
 302         a = ordered_hashmap_get(members, sg->sg_namp);
 303         if (a) {
 304                 _cleanup_strv_free_ char **l = NULL;
 305                 bool added = false;
 306                 char **i;
 307
 308                 l = strv_copy(sg->sg_mem);
 309                 if (!l)
 310                         return -ENOMEM;
 311
 312                 STRV_FOREACH(i, a) {
 313                         if (strv_find(l, *i))
 314                                 continue;
 315
 316                         if (strv_extend(&l, *i) < 0)
 317                                 return -ENOMEM;
 318
 319                         added = true;
 320                 }
 321
 322                 if (added) {
 323                         struct sgrp t;
 324                         int r;
 325
 326                         strv_uniq(l);
 327                         strv_sort(l);
 328
 329                         t = *sg;
 330                         t.sg_mem = l;
 331
 332                         r = putsgent_sane(&t, gshadow);
 333                         return r < 0 ? r : 1;
 334                 }
 335         }
 336
 337         return putsgent_sane(sg, gshadow);
 338 }
 339 #endif
 340
 341 static int sync_rights(FILE *from, FILE *to) {
 342         struct stat st;
 343
 344         if (fstat(fileno(from), &st) < 0)
 345                 return -errno;
 346
 347         return fchmod_and_chown(fileno(to), st.st_mode & 07777, st.st_uid, st.st_gid);
 348 }
 349
 350 static int rename_and_apply_smack(const char *temp_path, const char *dest_path) {
 351         int r = 0;
 352         if (rename(temp_path, dest_path) < 0)
 353                 return -errno;
 354
 355 #ifdef SMACK_RUN_LABEL
 356         r = mac_smack_apply(dest_path, SMACK_ATTR_ACCESS, SMACK_FLOOR_LABEL);
 357         if (r < 0)
 358                 return r;
 359 #endif
 360         return r;
 361 }
 362
 363 static const char* default_shell(uid_t uid) {
 364         return uid == 0 ? "/bin/sh" : "/sbin/nologin";
 365 }
 366
 367 static int write_temporary_passwd(const char *passwd_path, FILE **tmpfile, char **tmpfile_path) {
 368         _cleanup_fclose_ FILE *original = NULL, *passwd = NULL;
 369         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL;
 370         struct passwd *pw = NULL;
 371         Iterator iterator;
 372         Item *i;
 373         int r;
 374
 375         if (ordered_hashmap_size(todo_uids) == 0)
 376                 return 0;
 377
 378         r = fopen_temporary_label("/etc/passwd", passwd_path, &passwd, &passwd_tmp);
 379         if (r < 0)
 380                 return r;
 381
 382         original = fopen(passwd_path, "re");
 383         if (original) {
 384
 385                 r = sync_rights(original, passwd);
 386                 if (r < 0)
 387                         return r;
 388
 389                 while ((r = fgetpwent_sane(original, &pw)) > 0) {
 390
 391                         i = ordered_hashmap_get(users, pw->pw_name);
 392                         if (i && i->todo_user) {
 393                                 log_error("%s: User \"%s\" already exists.", passwd_path, pw->pw_name);
 394                                 return -EEXIST;
 395                         }
 396
 397                         if (ordered_hashmap_contains(todo_uids, UID_TO_PTR(pw->pw_uid))) {
 398                                 log_error("%s: Detected collision for UID " UID_FMT ".", passwd_path, pw->pw_uid);
 399                                 return -EEXIST;
 400                         }
 401
 402                         /* Make sure we keep the NIS entries (if any) at the end. */
 403                         if (IN_SET(pw->pw_name[0], '+', '-'))
 404                                 break;
 405
 406                         r = putpwent_sane(pw, passwd);
 407                         if (r < 0)
 408                                 return r;
 409                 }
 410                 if (r < 0)
 411                         return r;
 412
 413         } else {
 414                 if (errno != ENOENT)
 415                         return -errno;
 416                 if (fchmod(fileno(passwd), 0644) < 0)
 417                         return -errno;
 418         }
 419
 420         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 421                 struct passwd n = {
 422                         .pw_name = i->name,
 423                         .pw_uid = i->uid,
 424                         .pw_gid = i->gid,
 425                         .pw_gecos = i->description,
 426
 427                         /* "x" means the password is stored in the shadow file */
 428                         .pw_passwd = (char*) "x",
 429
 430                         /* We default to the root directory as home */
 431                         .pw_dir = i->home ? i->home : (char*) "/",
 432
 433                         /* Initialize the shell to nologin, with one exception:
 434                          * for root we patch in something special */
 435                         .pw_shell = i->shell ?: (char*) default_shell(i->uid),
 436                 };
 437
 438                 r = putpwent_sane(&n, passwd);
 439                 if (r < 0)
 440                         return r;
 441         }
 442
 443         /* Append the remaining NIS entries if any */
 444         while (pw) {
 445                 r = putpwent_sane(pw, passwd);
 446                 if (r < 0)
 447                         return r;
 448
 449                 r = fgetpwent_sane(original, &pw);
 450                 if (r < 0)
 451                         return r;
 452                 if (r == 0)
 453                         break;
 454         }
 455
 456         r = fflush_and_check(passwd);
 457         if (r < 0)
 458                 return r;
 459
 460         *tmpfile = TAKE_PTR(passwd);
 461         *tmpfile_path = TAKE_PTR(passwd_tmp);
 462
 463         return 0;
 464 }
 465
 466 static int write_temporary_shadow(const char *shadow_path, FILE **tmpfile, char **tmpfile_path) {
 467         _cleanup_fclose_ FILE *original = NULL, *shadow = NULL;
 468         _cleanup_(unlink_and_freep) char *shadow_tmp = NULL;
 469         struct spwd *sp = NULL;
 470         Iterator iterator;
 471         long lstchg;
 472         Item *i;
 473         int r;
 474
 475         if (ordered_hashmap_size(todo_uids) == 0)
 476                 return 0;
 477
 478         r = fopen_temporary_label("/etc/shadow", shadow_path, &shadow, &shadow_tmp);
 479         if (r < 0)
 480                 return r;
 481
 482         lstchg = (long) (now(CLOCK_REALTIME) / USEC_PER_DAY);
 483
 484         original = fopen(shadow_path, "re");
 485         if (original) {
 486
 487                 r = sync_rights(original, shadow);
 488                 if (r < 0)
 489                         return r;
 490
 491                 while ((r = fgetspent_sane(original, &sp)) > 0) {
 492
 493                         i = ordered_hashmap_get(users, sp->sp_namp);
 494                         if (i && i->todo_user) {
 495                                 /* we will update the existing entry */
 496                                 sp->sp_lstchg = lstchg;
 497
 498                                 /* only the /etc/shadow stage is left, so we can
 499                                  * safely remove the item from the todo set */
 500                                 i->todo_user = false;
 501                                 ordered_hashmap_remove(todo_uids, UID_TO_PTR(i->uid));
 502                         }
 503
 504                         /* Make sure we keep the NIS entries (if any) at the end. */
 505                         if (IN_SET(sp->sp_namp[0], '+', '-'))
 506                                 break;
 507
 508                         r = putspent_sane(sp, shadow);
 509                         if (r < 0)
 510                                 return r;
 511                 }
 512                 if (r < 0)
 513                         return r;
 514
 515         } else {
 516                 if (errno != ENOENT)
 517                         return -errno;
 518                 if (fchmod(fileno(shadow), 0000) < 0)
 519                         return -errno;
 520         }
 521
 522         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 523                 struct spwd n = {
 524                         .sp_namp = i->name,
 525                         .sp_pwdp = (char*) "!!",
 526                         .sp_lstchg = lstchg,
 527                         .sp_min = -1,
 528                         .sp_max = -1,
 529                         .sp_warn = -1,
 530                         .sp_inact = -1,
 531                         .sp_expire = -1,
 532                         .sp_flag = (unsigned long) -1, /* this appears to be what everybody does ... */
 533                 };
 534
 535                 r = putspent_sane(&n, shadow);
 536                 if (r < 0)
 537                         return r;
 538         }
 539
 540         /* Append the remaining NIS entries if any */
 541         while (sp) {
 542                 r = putspent_sane(sp, shadow);
 543                 if (r < 0)
 544                         return r;
 545
 546                 r = fgetspent_sane(original, &sp);
 547                 if (r < 0)
 548                         return r;
 549                 if (r == 0)
 550                         break;
 551         }
 552         if (!IN_SET(errno, 0, ENOENT))
 553                 return -errno;
 554
 555         r = fflush_sync_and_check(shadow);
 556         if (r < 0)
 557                 return r;
 558
 559         *tmpfile = TAKE_PTR(shadow);
 560         *tmpfile_path = TAKE_PTR(shadow_tmp);
 561
 562         return 0;
 563 }
 564
 565 static int write_temporary_group(const char *group_path, FILE **tmpfile, char **tmpfile_path) {
 566         _cleanup_fclose_ FILE *original = NULL, *group = NULL;
 567         _cleanup_(unlink_and_freep) char *group_tmp = NULL;
 568         bool group_changed = false;
 569         struct group *gr = NULL;
 570         Iterator iterator;
 571         Item *i;
 572         int r;
 573
 574         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 575                 return 0;
 576
 577         r = fopen_temporary_label("/etc/group", group_path, &group, &group_tmp);
 578         if (r < 0)
 579                 return r;
 580
 581         original = fopen(group_path, "re");
 582         if (original) {
 583
 584                 r = sync_rights(original, group);
 585                 if (r < 0)
 586                         return r;
 587
 588                 while ((r = fgetgrent_sane(original, &gr)) > 0) {
 589                         /* Safety checks against name and GID collisions. Normally,
 590                          * this should be unnecessary, but given that we look at the
 591                          * entries anyway here, let's make an extra verification
 592                          * step that we don't generate duplicate entries. */
 593
 594                         i = ordered_hashmap_get(groups, gr->gr_name);
 595                         if (i && i->todo_group) {
 596                                 log_error("%s: Group \"%s\" already exists.", group_path, gr->gr_name);
 597                                 return -EEXIST;
 598                         }
 599
 600                         if (ordered_hashmap_contains(todo_gids, GID_TO_PTR(gr->gr_gid))) {
 601                                 log_error("%s: Detected collision for GID " GID_FMT ".", group_path, gr->gr_gid);
 602                                 return  -EEXIST;
 603                         }
 604
 605                         /* Make sure we keep the NIS entries (if any) at the end. */
 606                         if (IN_SET(gr->gr_name[0], '+', '-'))
 607                                 break;
 608
 609                         r = putgrent_with_members(gr, group);
 610                         if (r < 0)
 611                                 return r;
 612                         if (r > 0)
 613                                 group_changed = true;
 614                 }
 615                 if (r < 0)
 616                         return r;
 617
 618         } else {
 619                 if (errno != ENOENT)
 620                         return -errno;
 621                 if (fchmod(fileno(group), 0644) < 0)
 622                         return -errno;
 623         }
 624
 625         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 626                 struct group n = {
 627                         .gr_name = i->name,
 628                         .gr_gid = i->gid,
 629                         .gr_passwd = (char*) "x",
 630                 };
 631
 632                 r = putgrent_with_members(&n, group);
 633                 if (r < 0)
 634                         return r;
 635
 636                 group_changed = true;
 637         }
 638
 639         /* Append the remaining NIS entries if any */
 640         while (gr) {
 641                 r = putgrent_sane(gr, group);
 642                 if (r < 0)
 643                         return r;
 644
 645                 r = fgetgrent_sane(original, &gr);
 646                 if (r < 0)
 647                         return r;
 648                 if (r == 0)
 649                         break;
 650         }
 651
 652         r = fflush_sync_and_check(group);
 653         if (r < 0)
 654                 return r;
 655
 656         if (group_changed) {
 657                 *tmpfile = TAKE_PTR(group);
 658                 *tmpfile_path = TAKE_PTR(group_tmp);
 659         }
 660         return 0;
 661 }
 662
 663 static int write_temporary_gshadow(const char * gshadow_path, FILE **tmpfile, char **tmpfile_path) {
 664 #if ENABLE_GSHADOW
 665         _cleanup_fclose_ FILE *original = NULL, *gshadow = NULL;
 666         _cleanup_(unlink_and_freep) char *gshadow_tmp = NULL;
 667         bool group_changed = false;
 668         Iterator iterator;
 669         Item *i;
 670         int r;
 671
 672         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 673                 return 0;
 674
 675         r = fopen_temporary_label("/etc/gshadow", gshadow_path, &gshadow, &gshadow_tmp);
 676         if (r < 0)
 677                 return r;
 678
 679         original = fopen(gshadow_path, "re");
 680         if (original) {
 681                 struct sgrp *sg;
 682
 683                 r = sync_rights(original, gshadow);
 684                 if (r < 0)
 685                         return r;
 686
 687                 while ((r = fgetsgent_sane(original, &sg)) > 0) {
 688
 689                         i = ordered_hashmap_get(groups, sg->sg_namp);
 690                         if (i && i->todo_group) {
 691                                 log_error("%s: Group \"%s\" already exists.", gshadow_path, sg->sg_namp);
 692                                 return -EEXIST;
 693                         }
 694
 695                         r = putsgent_with_members(sg, gshadow);
 696                         if (r < 0)
 697                                 return r;
 698                         if (r > 0)
 699                                 group_changed = true;
 700                 }
 701                 if (r < 0)
 702                         return r;
 703
 704         } else {
 705                 if (errno != ENOENT)
 706                         return -errno;
 707                 if (fchmod(fileno(gshadow), 0000) < 0)
 708                         return -errno;
 709         }
 710
 711         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 712                 struct sgrp n = {
 713                         .sg_namp = i->name,
 714                         .sg_passwd = (char*) "!!",
 715                 };
 716
 717                 r = putsgent_with_members(&n, gshadow);
 718                 if (r < 0)
 719                         return r;
 720
 721                 group_changed = true;
 722         }
 723
 724         r = fflush_sync_and_check(gshadow);
 725         if (r < 0)
 726                 return r;
 727
 728         if (group_changed) {
 729                 *tmpfile = TAKE_PTR(gshadow);
 730                 *tmpfile_path = TAKE_PTR(gshadow_tmp);
 731         }
 732         return 0;
 733 #else
 734         return 0;
 735 #endif
 736 }
 737
 738 static int write_files(void) {
 739         _cleanup_fclose_ FILE *passwd = NULL, *group = NULL, *shadow = NULL, *gshadow = NULL;
 740         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL, *group_tmp = NULL, *shadow_tmp = NULL, *gshadow_tmp = NULL;
 741         const char *passwd_path = NULL, *group_path = NULL, *shadow_path = NULL, *gshadow_path = NULL;
 742         int r;
 743
 744         passwd_path = prefix_roota(arg_root, "/etc/passwd");
 745         shadow_path = prefix_roota(arg_root, "/etc/shadow");
 746         group_path = prefix_roota(arg_root, "/etc/group");
 747         gshadow_path = prefix_roota(arg_root, "/etc/gshadow");
 748
 749         r = write_temporary_group(group_path, &group, &group_tmp);
 750         if (r < 0)
 751                 return r;
 752
 753         r = write_temporary_gshadow(gshadow_path, &gshadow, &gshadow_tmp);
 754         if (r < 0)
 755                 return r;
 756
 757         r = write_temporary_passwd(passwd_path, &passwd, &passwd_tmp);
 758         if (r < 0)
 759                 return r;
 760
 761         r = write_temporary_shadow(shadow_path, &shadow, &shadow_tmp);
 762         if (r < 0)
 763                 return r;
 764
 765         /* Make a backup of the old files */
 766         if (group) {
 767                 r = make_backup("/etc/group", group_path);
 768                 if (r < 0)
 769                         return r;
 770         }
 771         if (gshadow) {
 772                 r = make_backup("/etc/gshadow", gshadow_path);
 773                 if (r < 0)
 774                         return r;
 775         }
 776
 777         if (passwd) {
 778                 r = make_backup("/etc/passwd", passwd_path);
 779                 if (r < 0)
 780                         return r;
 781         }
 782         if (shadow) {
 783                 r = make_backup("/etc/shadow", shadow_path);
 784                 if (r < 0)
 785                         return r;
 786         }
 787
 788         /* And make the new files count */
 789         if (group) {
 790                 r = rename_and_apply_smack(group_tmp, group_path);
 791                 if (r < 0)
 792                         return r;
 793
 794                 group_tmp = mfree(group_tmp);
 795         }
 796         if (gshadow) {
 797                 r = rename_and_apply_smack(gshadow_tmp, gshadow_path);
 798                 if (r < 0)
 799                         return r;
 800
 801                 gshadow_tmp = mfree(gshadow_tmp);
 802         }
 803
 804         if (passwd) {
 805                 r = rename_and_apply_smack(passwd_tmp, passwd_path);
 806                 if (r < 0)
 807                         return r;
 808
 809                 passwd_tmp = mfree(passwd_tmp);
 810         }
 811         if (shadow) {
 812                 r = rename_and_apply_smack(shadow_tmp, shadow_path);
 813                 if (r < 0)
 814                         return r;
 815
 816                 shadow_tmp = mfree(shadow_tmp);
 817         }
 818
 819         return 0;
 820 }
 821
 822 static int uid_is_ok(uid_t uid, const char *name, bool check_with_gid) {
 823         struct passwd *p;
 824         struct group *g;
 825         const char *n;
 826         Item *i;
 827
 828         /* Let's see if we already have assigned the UID a second time */
 829         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(uid)))
 830                 return 0;
 831
 832         /* Try to avoid using uids that are already used by a group
 833          * that doesn't have the same name as our new user. */
 834         if (check_with_gid) {
 835                 i = ordered_hashmap_get(todo_gids, GID_TO_PTR(uid));
 836                 if (i && !streq(i->name, name))
 837                         return 0;
 838         }
 839
 840         /* Let's check the files directly */
 841         if (hashmap_contains(database_by_uid, UID_TO_PTR(uid)))
 842                 return 0;
 843
 844         if (check_with_gid) {
 845                 n = hashmap_get(database_by_gid, GID_TO_PTR(uid));
 846                 if (n && !streq(n, name))
 847                         return 0;
 848         }
 849
 850         /* Let's also check via NSS, to avoid UID clashes over LDAP and such, just in case */
 851         if (!arg_root) {
 852                 errno = 0;
 853                 p = getpwuid(uid);
 854                 if (p)
 855                         return 0;
 856                 if (!IN_SET(errno, 0, ENOENT))
 857                         return -errno;
 858
 859                 if (check_with_gid) {
 860                         errno = 0;
 861                         g = getgrgid((gid_t) uid);
 862                         if (g) {
 863                                 if (!streq(g->gr_name, name))
 864                                         return 0;
 865                         } else if (!IN_SET(errno, 0, ENOENT))
 866                                 return -errno;
 867                 }
 868         }
 869
 870         return 1;
 871 }
 872
 873 static int root_stat(const char *p, struct stat *st) {
 874         const char *fix;
 875
 876         fix = prefix_roota(arg_root, p);
 877         if (stat(fix, st) < 0)
 878                 return -errno;
 879
 880         return 0;
 881 }
 882
 883 static int read_id_from_file(Item *i, uid_t *_uid, gid_t *_gid) {
 884         struct stat st;
 885         bool found_uid = false, found_gid = false;
 886         uid_t uid = 0;
 887         gid_t gid = 0;
 888
 889         assert(i);
 890
 891         /* First, try to get the gid directly */
 892         if (_gid && i->gid_path && root_stat(i->gid_path, &st) >= 0) {
 893                 gid = st.st_gid;
 894                 found_gid = true;
 895         }
 896
 897         /* Then, try to get the uid directly */
 898         if ((_uid || (_gid && !found_gid))
 899             && i->uid_path
 900             && root_stat(i->uid_path, &st) >= 0) {
 901
 902                 uid = st.st_uid;
 903                 found_uid = true;
 904
 905                 /* If we need the gid, but had no success yet, also derive it from the uid path */
 906                 if (_gid && !found_gid) {
 907                         gid = st.st_gid;
 908                         found_gid = true;
 909                 }
 910         }
 911
 912         /* If that didn't work yet, then let's reuse the gid as uid */
 913         if (_uid && !found_uid && i->gid_path) {
 914
 915                 if (found_gid) {
 916                         uid = (uid_t) gid;
 917                         found_uid = true;
 918                 } else if (root_stat(i->gid_path, &st) >= 0) {
 919                         uid = (uid_t) st.st_gid;
 920                         found_uid = true;
 921                 }
 922         }
 923
 924         if (_uid) {
 925                 if (!found_uid)
 926                         return 0;
 927
 928                 *_uid = uid;
 929         }
 930
 931         if (_gid) {
 932                 if (!found_gid)
 933                         return 0;
 934
 935                 *_gid = gid;
 936         }
 937
 938         return 1;
 939 }
 940
 941 static int add_user(Item *i) {
 942         void *z;
 943         int r;
 944
 945         assert(i);
 946
 947         /* Check the database directly */
 948         z = hashmap_get(database_by_username, i->name);
 949         if (z) {
 950                 log_debug("User %s already exists.", i->name);
 951                 i->uid = PTR_TO_UID(z);
 952                 i->uid_set = true;
 953                 return 0;
 954         }
 955
 956         if (!arg_root) {
 957                 struct passwd *p;
 958
 959                 /* Also check NSS */
 960                 errno = 0;
 961                 p = getpwnam(i->name);
 962                 if (p) {
 963                         log_debug("User %s already exists.", i->name);
 964                         i->uid = p->pw_uid;
 965                         i->uid_set = true;
 966
 967                         r = free_and_strdup(&i->description, p->pw_gecos);
 968                         if (r < 0)
 969                                 return log_oom();
 970
 971                         return 0;
 972                 }
 973                 if (!IN_SET(errno, 0, ENOENT))
 974                         return log_error_errno(errno, "Failed to check if user %s already exists: %m", i->name);
 975         }
 976
 977         /* Try to use the suggested numeric uid */
 978         if (i->uid_set) {
 979                 r = uid_is_ok(i->uid, i->name, !i->id_set_strict);
 980                 if (r < 0)
 981                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
 982                 if (r == 0) {
 983                         log_debug("Suggested user ID " UID_FMT " for %s already used.", i->uid, i->name);
 984                         i->uid_set = false;
 985                 }
 986         }
 987
 988         /* If that didn't work, try to read it from the specified path */
 989         if (!i->uid_set) {
 990                 uid_t c;
 991
 992                 if (read_id_from_file(i, &c, NULL) > 0) {
 993
 994                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
 995                                 log_debug("User ID " UID_FMT " of file not suitable for %s.", c, i->name);
 996                         else {
 997                                 r = uid_is_ok(c, i->name, true);
 998                                 if (r < 0)
 999                                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1000                                 else if (r > 0) {
1001                                         i->uid = c;
1002                                         i->uid_set = true;
1003                                 } else
1004                                         log_debug("User ID " UID_FMT " of file for %s is already used.", c, i->name);
1005                         }
1006                 }
1007         }
1008
1009         /* Otherwise, try to reuse the group ID */
1010         if (!i->uid_set && i->gid_set) {
1011                 r = uid_is_ok((uid_t) i->gid, i->name, true);
1012                 if (r < 0)
1013                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1014                 if (r > 0) {
1015                         i->uid = (uid_t) i->gid;
1016                         i->uid_set = true;
1017                 }
1018         }
1019
1020         /* And if that didn't work either, let's try to find a free one */
1021         if (!i->uid_set) {
1022                 for (;;) {
1023                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1024                         if (r < 0) {
1025                                 log_error("No free user ID available for %s.", i->name);
1026                                 return r;
1027                         }
1028
1029                         r = uid_is_ok(search_uid, i->name, true);
1030                         if (r < 0)
1031                                 return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1032                         else if (r > 0)
1033                                 break;
1034                 }
1035
1036                 i->uid_set = true;
1037                 i->uid = search_uid;
1038         }
1039
1040         r = ordered_hashmap_ensure_allocated(&todo_uids, NULL);
1041         if (r < 0)
1042                 return log_oom();
1043
1044         r = ordered_hashmap_put(todo_uids, UID_TO_PTR(i->uid), i);
1045         if (r < 0)
1046                 return log_oom();
1047
1048         i->todo_user = true;
1049         log_info("Creating user %s (%s) with uid " UID_FMT " and gid " GID_FMT ".", i->name, strna(i->description), i->uid, i->gid);
1050
1051         return 0;
1052 }
1053
1054 static int gid_is_ok(gid_t gid) {
1055         struct group *g;
1056         struct passwd *p;
1057
1058         if (ordered_hashmap_get(todo_gids, GID_TO_PTR(gid)))
1059                 return 0;
1060
1061         /* Avoid reusing gids that are already used by a different user */
1062         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(gid)))
1063                 return 0;
1064
1065         if (hashmap_contains(database_by_gid, GID_TO_PTR(gid)))
1066                 return 0;
1067
1068         if (hashmap_contains(database_by_uid, UID_TO_PTR(gid)))
1069                 return 0;
1070
1071         if (!arg_root) {
1072                 errno = 0;
1073                 g = getgrgid(gid);
1074                 if (g)
1075                         return 0;
1076                 if (!IN_SET(errno, 0, ENOENT))
1077                         return -errno;
1078
1079                 errno = 0;
1080                 p = getpwuid((uid_t) gid);
1081                 if (p)
1082                         return 0;
1083                 if (!IN_SET(errno, 0, ENOENT))
1084                         return -errno;
1085         }
1086
1087         return 1;
1088 }
1089
1090 static int add_group(Item *i) {
1091         void *z;
1092         int r;
1093
1094         assert(i);
1095
1096         /* Check the database directly */
1097         z = hashmap_get(database_by_groupname, i->name);
1098         if (z) {
1099                 log_debug("Group %s already exists.", i->name);
1100                 i->gid = PTR_TO_GID(z);
1101                 i->gid_set = true;
1102                 return 0;
1103         }
1104
1105         /* Also check NSS */
1106         if (!arg_root) {
1107                 struct group *g;
1108
1109                 errno = 0;
1110                 g = getgrnam(i->name);
1111                 if (g) {
1112                         log_debug("Group %s already exists.", i->name);
1113                         i->gid = g->gr_gid;
1114                         i->gid_set = true;
1115                         return 0;
1116                 }
1117                 if (!IN_SET(errno, 0, ENOENT))
1118                         return log_error_errno(errno, "Failed to check if group %s already exists: %m", i->name);
1119         }
1120
1121         /* Try to use the suggested numeric gid */
1122         if (i->gid_set) {
1123                 r = gid_is_ok(i->gid);
1124                 if (r < 0)
1125                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1126                 if (i->id_set_strict) {
1127                         /* If we require the gid to already exist we can return here:
1128                          * r > 0: means the gid does not exist -> fail
1129                          * r == 0: means the gid exists -> nothing more to do.
1130                          */
1131                         if (r > 0)
1132                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
1133                                                        "Failed to create %s: please create GID %d",
1134                                                        i->name, i->gid);
1135                         if (r == 0)
1136                                 return 0;
1137                 }
1138                 if (r == 0) {
1139                         log_debug("Suggested group ID " GID_FMT " for %s already used.", i->gid, i->name);
1140                         i->gid_set = false;
1141                 }
1142         }
1143
1144         /* Try to reuse the numeric uid, if there's one */
1145         if (!i->gid_set && i->uid_set) {
1146                 r = gid_is_ok((gid_t) i->uid);
1147                 if (r < 0)
1148                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1149                 if (r > 0) {
1150                         i->gid = (gid_t) i->uid;
1151                         i->gid_set = true;
1152                 }
1153         }
1154
1155         /* If that didn't work, try to read it from the specified path */
1156         if (!i->gid_set) {
1157                 gid_t c;
1158
1159                 if (read_id_from_file(i, NULL, &c) > 0) {
1160
1161                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
1162                                 log_debug("Group ID " GID_FMT " of file not suitable for %s.", c, i->name);
1163                         else {
1164                                 r = gid_is_ok(c);
1165                                 if (r < 0)
1166                                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1167                                 else if (r > 0) {
1168                                         i->gid = c;
1169                                         i->gid_set = true;
1170                                 } else
1171                                         log_debug("Group ID " GID_FMT " of file for %s already used.", c, i->name);
1172                         }
1173                 }
1174         }
1175
1176         /* And if that didn't work either, let's try to find a free one */
1177         if (!i->gid_set) {
1178                 for (;;) {
1179                         /* We look for new GIDs in the UID pool! */
1180                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1181                         if (r < 0) {
1182                                 log_error("No free group ID available for %s.", i->name);
1183                                 return r;
1184                         }
1185
1186                         r = gid_is_ok(search_uid);
1187                         if (r < 0)
1188                                 return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1189                         else if (r > 0)
1190                                 break;
1191                 }
1192
1193                 i->gid_set = true;
1194                 i->gid = search_uid;
1195         }
1196
1197         r = ordered_hashmap_ensure_allocated(&todo_gids, NULL);
1198         if (r < 0)
1199                 return log_oom();
1200
1201         r = ordered_hashmap_put(todo_gids, GID_TO_PTR(i->gid), i);
1202         if (r < 0)
1203                 return log_oom();
1204
1205         i->todo_group = true;
1206         log_info("Creating group %s with gid " GID_FMT ".", i->name, i->gid);
1207
1208         return 0;
1209 }
1210
1211 static int process_item(Item *i) {
1212         int r;
1213
1214         assert(i);
1215
1216         switch (i->type) {
1217
1218         case ADD_USER: {
1219                 Item *j;
1220
1221                 j = ordered_hashmap_get(groups, i->name);
1222                 if (j && j->todo_group) {
1223                         /* When the group with the same name is already in queue,
1224                          * use the information about the group and do not create
1225                          * duplicated group entry. */
1226                         i->gid_set = j->gid_set;
1227                         i->gid = j->gid;
1228                         i->id_set_strict = true;
1229                 } else {
1230                         r = add_group(i);
1231                         if (r < 0)
1232                                 return r;
1233                 }
1234
1235                 return add_user(i);
1236         }
1237
1238         case ADD_GROUP:
1239                 return add_group(i);
1240
1241         default:
1242                 assert_not_reached("Unknown item type");
1243         }
1244 }
1245
1246 static Item* item_free(Item *i) {
1247         if (!i)
1248                 return NULL;
1249
1250         free(i->name);
1251         free(i->uid_path);
1252         free(i->gid_path);
1253         free(i->description);
1254         free(i->home);
1255         free(i->shell);
1256         return mfree(i);
1257 }
1258
1259 DEFINE_TRIVIAL_CLEANUP_FUNC(Item*, item_free);
1260 DEFINE_PRIVATE_HASH_OPS_WITH_VALUE_DESTRUCTOR(item_hash_ops, char, string_hash_func, string_compare_func, Item, item_free);
1261
1262 static int add_implicit(void) {
1263         char *g, **l;
1264         Iterator iterator;
1265         int r;
1266
1267         /* Implicitly create additional users and groups, if they were listed in "m" lines */
1268         ORDERED_HASHMAP_FOREACH_KEY(l, g, members, iterator) {
1269                 char **m;
1270
1271                 STRV_FOREACH(m, l)
1272                         if (!ordered_hashmap_get(users, *m)) {
1273                                 _cleanup_(item_freep) Item *j = NULL;
1274
1275                                 r = ordered_hashmap_ensure_allocated(&users, &item_hash_ops);
1276                                 if (r < 0)
1277                                         return log_oom();
1278
1279                                 j = new0(Item, 1);
1280                                 if (!j)
1281                                         return log_oom();
1282
1283                                 j->type = ADD_USER;
1284                                 j->name = strdup(*m);
1285                                 if (!j->name)
1286                                         return log_oom();
1287
1288                                 r = ordered_hashmap_put(users, j->name, j);
1289                                 if (r < 0)
1290                                         return log_oom();
1291
1292                                 log_debug("Adding implicit user '%s' due to m line", j->name);
1293                                 j = NULL;
1294                         }
1295
1296                 if (!(ordered_hashmap_get(users, g) ||
1297                       ordered_hashmap_get(groups, g))) {
1298                         _cleanup_(item_freep) Item *j = NULL;
1299
1300                         r = ordered_hashmap_ensure_allocated(&groups, &item_hash_ops);
1301                         if (r < 0)
1302                                 return log_oom();
1303
1304                         j = new0(Item, 1);
1305                         if (!j)
1306                                 return log_oom();
1307
1308                         j->type = ADD_GROUP;
1309                         j->name = strdup(g);
1310                         if (!j->name)
1311                                 return log_oom();
1312
1313                         r = ordered_hashmap_put(groups, j->name, j);
1314                         if (r < 0)
1315                                 return log_oom();
1316
1317                         log_debug("Adding implicit group '%s' due to m line", j->name);
1318                         j = NULL;
1319                 }
1320         }
1321
1322         return 0;
1323 }
1324
1325 static bool item_equal(Item *a, Item *b) {
1326         assert(a);
1327         assert(b);
1328
1329         if (a->type != b->type)
1330                 return false;
1331
1332         if (!streq_ptr(a->name, b->name))
1333                 return false;
1334
1335         if (!streq_ptr(a->uid_path, b->uid_path))
1336                 return false;
1337
1338         if (!streq_ptr(a->gid_path, b->gid_path))
1339                 return false;
1340
1341         if (!streq_ptr(a->description, b->description))
1342                 return false;
1343
1344         if (a->uid_set != b->uid_set)
1345                 return false;
1346
1347         if (a->uid_set && a->uid != b->uid)
1348                 return false;
1349
1350         if (a->gid_set != b->gid_set)
1351                 return false;
1352
1353         if (a->gid_set && a->gid != b->gid)
1354                 return false;
1355
1356         if (!streq_ptr(a->home, b->home))
1357                 return false;
1358
1359         if (!streq_ptr(a->shell, b->shell))
1360                 return false;
1361
1362         return true;
1363 }
1364
1365 DEFINE_PRIVATE_HASH_OPS_FULL(members_hash_ops, char, string_hash_func, string_compare_func, free, char*, strv_free);
1366
1367 static int parse_line(const char *fname, unsigned line, const char *buffer) {
1368
1369         static const Specifier specifier_table[] = {
1370                 { 'm', specifier_machine_id,     NULL },
1371                 { 'b', specifier_boot_id,        NULL },
1372                 { 'H', specifier_host_name,      NULL },
1373                 { 'v', specifier_kernel_release, NULL },
1374                 { 'T', specifier_tmp_dir,        NULL },
1375                 { 'V', specifier_var_tmp_dir,    NULL },
1376                 {}
1377         };
1378
1379         _cleanup_free_ char *action = NULL,
1380                 *name = NULL, *resolved_name = NULL,
1381                 *id = NULL, *resolved_id = NULL,
1382                 *description = NULL, *resolved_description = NULL,
1383                 *home = NULL, *resolved_home = NULL,
1384                 *shell, *resolved_shell = NULL;
1385         _cleanup_(item_freep) Item *i = NULL;
1386         Item *existing;
1387         OrderedHashmap *h;
1388         int r;
1389         const char *p;
1390
1391         assert(fname);
1392         assert(line >= 1);
1393         assert(buffer);
1394
1395         /* Parse columns */
1396         p = buffer;
1397         r = extract_many_words(&p, NULL, EXTRACT_QUOTES,
1398                                &action, &name, &id, &description, &home, &shell, NULL);
1399         if (r < 0) {
1400                 log_error("[%s:%u] Syntax error.", fname, line);
1401                 return r;
1402         }
1403         if (r < 2) {
1404                 log_error("[%s:%u] Missing action and name columns.", fname, line);
1405                 return -EINVAL;
1406         }
1407         if (!isempty(p)) {
1408                 log_error("[%s:%u] Trailing garbage.", fname, line);
1409                 return -EINVAL;
1410         }
1411
1412         /* Verify action */
1413         if (strlen(action) != 1) {
1414                 log_error("[%s:%u] Unknown modifier '%s'", fname, line, action);
1415                 return -EINVAL;
1416         }
1417
1418         if (!IN_SET(action[0], ADD_USER, ADD_GROUP, ADD_MEMBER, ADD_RANGE)) {
1419                 log_error("[%s:%u] Unknown command type '%c'.", fname, line, action[0]);
1420                 return -EBADMSG;
1421         }
1422
1423         /* Verify name */
1424         if (isempty(name) || streq(name, "-"))
1425                 name = mfree(name);
1426
1427         if (name) {
1428                 r = specifier_printf(name, specifier_table, NULL, &resolved_name);
1429                 if (r < 0) {
1430                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1431                         return r;
1432                 }
1433
1434                 if (!valid_user_group_name(resolved_name)) {
1435                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_name);
1436                         return -EINVAL;
1437                 }
1438         }
1439
1440         /* Verify id */
1441         if (isempty(id) || streq(id, "-"))
1442                 id = mfree(id);
1443
1444         if (id) {
1445                 r = specifier_printf(id, specifier_table, NULL, &resolved_id);
1446                 if (r < 0) {
1447                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1448                         return r;
1449                 }
1450         }
1451
1452         /* Verify description */
1453         if (isempty(description) || streq(description, "-"))
1454                 description = mfree(description);
1455
1456         if (description) {
1457                 r = specifier_printf(description, specifier_table, NULL, &resolved_description);
1458                 if (r < 0) {
1459                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, description);
1460                         return r;
1461                 }
1462
1463                 if (!valid_gecos(resolved_description)) {
1464                         log_error("[%s:%u] '%s' is not a valid GECOS field.", fname, line, resolved_description);
1465                         return -EINVAL;
1466                 }
1467         }
1468
1469         /* Verify home */
1470         if (isempty(home) || streq(home, "-"))
1471                 home = mfree(home);
1472
1473         if (home) {
1474                 r = specifier_printf(home, specifier_table, NULL, &resolved_home);
1475                 if (r < 0) {
1476                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, home);
1477                         return r;
1478                 }
1479
1480                 if (!valid_home(resolved_home)) {
1481                         log_error("[%s:%u] '%s' is not a valid home directory field.", fname, line, resolved_home);
1482                         return -EINVAL;
1483                 }
1484         }
1485
1486         /* Verify shell */
1487         if (isempty(shell) || streq(shell, "-"))
1488                 shell = mfree(shell);
1489
1490         if (shell) {
1491                 r = specifier_printf(shell, specifier_table, NULL, &resolved_shell);
1492                 if (r < 0) {
1493                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, shell);
1494                         return r;
1495                 }
1496
1497                 if (!valid_shell(resolved_shell)) {
1498                         log_error("[%s:%u] '%s' is not a valid login shell field.", fname, line, resolved_shell);
1499                         return -EINVAL;
1500                 }
1501         }
1502
1503         switch (action[0]) {
1504
1505         case ADD_RANGE:
1506                 if (resolved_name) {
1507                         log_error("[%s:%u] Lines of type 'r' don't take a name field.", fname, line);
1508                         return -EINVAL;
1509                 }
1510
1511                 if (!resolved_id) {
1512                         log_error("[%s:%u] Lines of type 'r' require a ID range in the third field.", fname, line);
1513                         return -EINVAL;
1514                 }
1515
1516                 if (description || home || shell) {
1517                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1518                                   fname, line, action[0],
1519                                   description ? "GECOS" : home ? "home directory" : "login shell");
1520                         return -EINVAL;
1521                 }
1522
1523                 r = uid_range_add_str(&uid_range, &n_uid_range, resolved_id);
1524                 if (r < 0) {
1525                         log_error("[%s:%u] Invalid UID range %s.", fname, line, resolved_id);
1526                         return -EINVAL;
1527                 }
1528
1529                 return 0;
1530
1531         case ADD_MEMBER: {
1532                 char **l;
1533
1534                 /* Try to extend an existing member or group item */
1535                 if (!name) {
1536                         log_error("[%s:%u] Lines of type 'm' require a user name in the second field.", fname, line);
1537                         return -EINVAL;
1538                 }
1539
1540                 if (!resolved_id) {
1541                         log_error("[%s:%u] Lines of type 'm' require a group name in the third field.", fname, line);
1542                         return -EINVAL;
1543                 }
1544
1545                 if (!valid_user_group_name(resolved_id)) {
1546                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_id);
1547                         return -EINVAL;
1548                 }
1549
1550                 if (description || home || shell) {
1551                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1552                                   fname, line, action[0],
1553                                   description ? "GECOS" : home ? "home directory" : "login shell");
1554                         return -EINVAL;
1555                 }
1556
1557                 r = ordered_hashmap_ensure_allocated(&members, &members_hash_ops);
1558                 if (r < 0)
1559                         return log_oom();
1560
1561                 l = ordered_hashmap_get(members, resolved_id);
1562                 if (l) {
1563                         /* A list for this group name already exists, let's append to it */
1564                         r = strv_push(&l, resolved_name);
1565                         if (r < 0)
1566                                 return log_oom();
1567
1568                         resolved_name = NULL;
1569
1570                         assert_se(ordered_hashmap_update(members, resolved_id, l) >= 0);
1571                 } else {
1572                         /* No list for this group name exists yet, create one */
1573
1574                         l = new0(char *, 2);
1575                         if (!l)
1576                                 return -ENOMEM;
1577
1578                         l[0] = resolved_name;
1579                         l[1] = NULL;
1580
1581                         r = ordered_hashmap_put(members, resolved_id, l);
1582                         if (r < 0) {
1583                                 free(l);
1584                                 return log_oom();
1585                         }
1586
1587                         resolved_id = resolved_name = NULL;
1588                 }
1589
1590                 return 0;
1591         }
1592
1593         case ADD_USER:
1594                 if (!name) {
1595                         log_error("[%s:%u] Lines of type 'u' require a user name in the second field.", fname, line);
1596                         return -EINVAL;
1597                 }
1598
1599                 r = ordered_hashmap_ensure_allocated(&users, &item_hash_ops);
1600                 if (r < 0)
1601                         return log_oom();
1602
1603                 i = new0(Item, 1);
1604                 if (!i)
1605                         return log_oom();
1606
1607                 if (resolved_id) {
1608                         if (path_is_absolute(resolved_id)) {
1609                                 i->uid_path = TAKE_PTR(resolved_id);
1610                                 path_simplify(i->uid_path, false);
1611                         } else {
1612                                 _cleanup_free_ char *uid = NULL, *gid = NULL;
1613                                 if (split_pair(resolved_id, ":", &uid, &gid) == 0) {
1614                                         r = parse_gid(gid, &i->gid);
1615                                         if (r < 0)
1616                                                 return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1617                                         i->gid_set = true;
1618                                         i->id_set_strict = true;
1619                                         free_and_replace(resolved_id, uid);
1620                                 }
1621                                 if (!streq(resolved_id, "-")) {
1622                                         r = parse_uid(resolved_id, &i->uid);
1623                                         if (r < 0)
1624                                                 return log_error_errno(r, "Failed to parse UID: '%s': %m", id);
1625                                         i->uid_set = true;
1626                                 }
1627                         }
1628                 }
1629
1630                 i->description = TAKE_PTR(resolved_description);
1631                 i->home = TAKE_PTR(resolved_home);
1632                 i->shell = TAKE_PTR(resolved_shell);
1633
1634                 h = users;
1635                 break;
1636
1637         case ADD_GROUP:
1638                 if (!name) {
1639                         log_error("[%s:%u] Lines of type 'g' require a user name in the second field.", fname, line);
1640                         return -EINVAL;
1641                 }
1642
1643                 if (description || home || shell) {
1644                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1645                                   fname, line, action[0],
1646                                   description ? "GECOS" : home ? "home directory" : "login shell");
1647                         return -EINVAL;
1648                 }
1649
1650                 r = ordered_hashmap_ensure_allocated(&groups, &item_hash_ops);
1651                 if (r < 0)
1652                         return log_oom();
1653
1654                 i = new0(Item, 1);
1655                 if (!i)
1656                         return log_oom();
1657
1658                 if (resolved_id) {
1659                         if (path_is_absolute(resolved_id)) {
1660                                 i->gid_path = TAKE_PTR(resolved_id);
1661                                 path_simplify(i->gid_path, false);
1662                         } else {
1663                                 r = parse_gid(resolved_id, &i->gid);
1664                                 if (r < 0)
1665                                         return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1666
1667                                 i->gid_set = true;
1668                         }
1669                 }
1670
1671                 h = groups;
1672                 break;
1673
1674         default:
1675                 return -EBADMSG;
1676         }
1677
1678         i->type = action[0];
1679         i->name = TAKE_PTR(resolved_name);
1680
1681         existing = ordered_hashmap_get(h, i->name);
1682         if (existing) {
1683
1684                 /* Two identical items are fine */
1685                 if (!item_equal(existing, i))
1686                         log_warning("Two or more conflicting lines for %s configured, ignoring.", i->name);
1687
1688                 return 0;
1689         }
1690
1691         r = ordered_hashmap_put(h, i->name, i);
1692         if (r < 0)
1693                 return log_oom();
1694
1695         i = NULL;
1696         return 0;
1697 }
1698
1699 static int read_config_file(const char *fn, bool ignore_enoent) {
1700         _cleanup_fclose_ FILE *rf = NULL;
1701         FILE *f = NULL;
1702         unsigned v = 0;
1703         int r = 0;
1704
1705         assert(fn);
1706
1707         if (streq(fn, "-"))
1708                 f = stdin;
1709         else {
1710                 r = search_and_fopen(fn, "re", arg_root, (const char**) CONF_PATHS_STRV("sysusers.d"), &rf);
1711                 if (r < 0) {
1712                         if (ignore_enoent && r == -ENOENT)
1713                                 return 0;
1714
1715                         return log_error_errno(r, "Failed to open '%s', ignoring: %m", fn);
1716                 }
1717
1718                 f = rf;
1719         }
1720
1721         for (;;) {
1722                 _cleanup_free_ char *line = NULL;
1723                 char *l;
1724                 int k;
1725
1726                 k = read_line(f, LONG_LINE_MAX, &line);
1727                 if (k < 0)
1728                         return log_error_errno(k, "Failed to read '%s': %m", fn);
1729                 if (k == 0)
1730                         break;
1731
1732                 v++;
1733
1734                 l = strstrip(line);
1735                 if (IN_SET(*l, 0, '#'))
1736                         continue;
1737
1738                 k = parse_line(fn, v, l);
1739                 if (k < 0 && r == 0)
1740                         r = k;
1741         }
1742
1743         if (ferror(f)) {
1744                 log_error_errno(errno, "Failed to read from file %s: %m", fn);
1745                 if (r == 0)
1746                         r = -EIO;
1747         }
1748
1749         return r;
1750 }
1751
1752 static int cat_config(void) {
1753         _cleanup_strv_free_ char **files = NULL;
1754         int r;
1755
1756         r = conf_files_list_with_replacement(arg_root, CONF_PATHS_STRV("sysusers.d"), arg_replace, &files, NULL);
1757         if (r < 0)
1758                 return r;
1759
1760         (void) pager_open(arg_pager_flags);
1761
1762         return cat_files(NULL, files, 0);
1763 }
1764
1765 static int help(void) {
1766         _cleanup_free_ char *link = NULL;
1767         int r;
1768
1769         r = terminal_urlify_man("systemd-sysusers.service", "8", &link);
1770         if (r < 0)
1771                 return log_oom();
1772
1773         printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
1774                "Creates system user accounts.\n\n"
1775                "  -h --help                 Show this help\n"
1776                "     --version              Show package version\n"
1777                "     --cat-config           Show configuration files\n"
1778                "     --root=PATH            Operate on an alternate filesystem root\n"
1779                "     --replace=PATH         Treat arguments as replacement for PATH\n"
1780                "     --inline               Treat arguments as configuration lines\n"
1781                "     --no-pager             Do not pipe output into a pager\n"
1782                "\nSee the %s for details.\n"
1783                , program_invocation_short_name
1784                , link
1785         );
1786
1787         return 0;
1788 }
1789
1790 static int parse_argv(int argc, char *argv[]) {
1791
1792         enum {
1793                 ARG_VERSION = 0x100,
1794                 ARG_CAT_CONFIG,
1795                 ARG_ROOT,
1796                 ARG_REPLACE,
1797                 ARG_INLINE,
1798                 ARG_NO_PAGER,
1799         };
1800
1801         static const struct option options[] = {
1802                 { "help",       no_argument,       NULL, 'h'            },
1803                 { "version",    no_argument,       NULL, ARG_VERSION    },
1804                 { "cat-config", no_argument,       NULL, ARG_CAT_CONFIG },
1805                 { "root",       required_argument, NULL, ARG_ROOT       },
1806                 { "replace",    required_argument, NULL, ARG_REPLACE    },
1807                 { "inline",     no_argument,       NULL, ARG_INLINE     },
1808                 { "no-pager",   no_argument,       NULL, ARG_NO_PAGER   },
1809                 {}
1810         };
1811
1812         int c, r;
1813
1814         assert(argc >= 0);
1815         assert(argv);
1816
1817         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
1818
1819                 switch (c) {
1820
1821                 case 'h':
1822                         return help();
1823
1824                 case ARG_VERSION:
1825                         return version();
1826
1827                 case ARG_CAT_CONFIG:
1828                         arg_cat_config = true;
1829                         break;
1830
1831                 case ARG_ROOT:
1832                         r = parse_path_argument_and_warn(optarg, true, &arg_root);
1833                         if (r < 0)
1834                                 return r;
1835                         break;
1836
1837                 case ARG_REPLACE:
1838                         if (!path_is_absolute(optarg) ||
1839                             !endswith(optarg, ".conf"))
1840                                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
1841                                                        "The argument to --replace= must an absolute path to a config file");
1842
1843                         arg_replace = optarg;
1844                         break;
1845
1846                 case ARG_INLINE:
1847                         arg_inline = true;
1848                         break;
1849
1850                 case ARG_NO_PAGER:
1851                         arg_pager_flags |= PAGER_DISABLE;
1852                         break;
1853
1854                 case '?':
1855                         return -EINVAL;
1856
1857                 default:
1858                         assert_not_reached("Unhandled option");
1859                 }
1860
1861         if (arg_replace && arg_cat_config)
1862                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
1863                                        "Option --replace= is not supported with --cat-config");
1864
1865         if (arg_replace && optind >= argc)
1866                 return log_error_errno(SYNTHETIC_ERRNO(EINVAL),
1867                                        "When --replace= is given, some configuration items must be specified");
1868
1869         return 1;
1870 }
1871
1872 static int parse_arguments(char **args) {
1873         char **arg;
1874         unsigned pos = 1;
1875         int r;
1876
1877         STRV_FOREACH(arg, args) {
1878                 if (arg_inline)
1879                         /* Use (argument):n, where n==1 for the first positional arg */
1880                         r = parse_line("(argument)", pos, *arg);
1881                 else
1882                         r = read_config_file(*arg, false);
1883                 if (r < 0)
1884                         return r;
1885
1886                 pos++;
1887         }
1888
1889         return 0;
1890 }
1891
1892 static int read_config_files(char **args) {
1893         _cleanup_strv_free_ char **files = NULL;
1894         _cleanup_free_ char *p = NULL;
1895         char **f;
1896         int r;
1897
1898         r = conf_files_list_with_replacement(arg_root, CONF_PATHS_STRV("sysusers.d"), arg_replace, &files, &p);
1899         if (r < 0)
1900                 return r;
1901
1902         STRV_FOREACH(f, files)
1903                 if (p && path_equal(*f, p)) {
1904                         log_debug("Parsing arguments at position \"%s\"…", *f);
1905
1906                         r = parse_arguments(args);
1907                         if (r < 0)
1908                                 return r;
1909                 } else {
1910                         log_debug("Reading config file \"%s\"…", *f);
1911
1912                         /* Just warn, ignore result otherwise */
1913                         (void) read_config_file(*f, true);
1914                 }
1915
1916         return 0;
1917 }
1918
1919 static int run(int argc, char *argv[]) {
1920         _cleanup_close_ int lock = -1;
1921         Iterator iterator;
1922         Item *i;
1923         int r;
1924
1925         r = parse_argv(argc, argv);
1926         if (r <= 0)
1927                 return r;
1928
1929         log_setup_service();
1930
1931         if (arg_cat_config)
1932                 return cat_config();
1933
1934         umask(0022);
1935
1936         r = mac_selinux_init();
1937         if (r < 0)
1938                 return log_error_errno(r, "SELinux setup failed: %m");
1939
1940         /* If command line arguments are specified along with --replace, read all
1941          * configuration files and insert the positional arguments at the specified
1942          * place. Otherwise, if command line arguments are specified, execute just
1943          * them, and finally, without --replace= or any positional arguments, just
1944          * read configuration and execute it.
1945          */
1946         if (arg_replace || optind >= argc)
1947                 r = read_config_files(argv + optind);
1948         else
1949                 r = parse_arguments(argv + optind);
1950         if (r < 0)
1951                 return r;
1952
1953         /* Let's tell nss-systemd not to synthesize the "root" and "nobody" entries for it, so that our detection
1954          * whether the names or UID/GID area already used otherwise doesn't get confused. After all, even though
1955          * nss-systemd synthesizes these users/groups, they should still appear in /etc/passwd and /etc/group, as the
1956          * synthesizing logic is merely supposed to be fallback for cases where we run with a completely unpopulated
1957          * /etc. */
1958         if (setenv("SYSTEMD_NSS_BYPASS_SYNTHETIC", "1", 1) < 0)
1959                 return log_error_errno(errno, "Failed to set SYSTEMD_NSS_BYPASS_SYNTHETIC environment variable: %m");
1960
1961         if (!uid_range) {
1962                 /* Default to default range of 1..SYSTEM_UID_MAX */
1963                 r = uid_range_add(&uid_range, &n_uid_range, 1, SYSTEM_UID_MAX);
1964                 if (r < 0)
1965                         return log_oom();
1966         }
1967
1968         r = add_implicit();
1969         if (r < 0)
1970                 return r;
1971
1972         lock = take_etc_passwd_lock(arg_root);
1973         if (lock < 0)
1974                 return log_error_errno(lock, "Failed to take /etc/passwd lock: %m");
1975
1976         r = load_user_database();
1977         if (r < 0)
1978                 return log_error_errno(r, "Failed to load user database: %m");
1979
1980         r = load_group_database();
1981         if (r < 0)
1982                 return log_error_errno(r, "Failed to read group database: %m");
1983
1984         ORDERED_HASHMAP_FOREACH(i, groups, iterator)
1985                 (void) process_item(i);
1986
1987         ORDERED_HASHMAP_FOREACH(i, users, iterator)
1988                 (void) process_item(i);
1989
1990         r = write_files();
1991         if (r < 0)
1992                 return log_error_errno(r, "Failed to write files: %m");
1993
1994         return 0;
1995 }
1996
1997 DEFINE_MAIN_FUNCTION(run);