src/sysusers/sysusers.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   This file is part of systemd.
   4
   5   Copyright 2014 Lennart Poettering
   6 ***/
   7
   8 #include <getopt.h>
   9 #include <utmp.h>
  10
  11 #include "alloc-util.h"
  12 #include "conf-files.h"
  13 #include "copy.h"
  14 #include "def.h"
  15 #include "fd-util.h"
  16 #include "fs-util.h"
  17 #include "fileio-label.h"
  18 #include "format-util.h"
  19 #include "hashmap.h"
  20 #include "path-util.h"
  21 #include "selinux-util.h"
  22 #include "smack-util.h"
  23 #include "specifier.h"
  24 #include "string-util.h"
  25 #include "strv.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 typedef struct Item {
  38         ItemType type;
  39
  40         char *name;
  41         char *uid_path;
  42         char *gid_path;
  43         char *description;
  44         char *home;
  45         char *shell;
  46
  47         gid_t gid;
  48         uid_t uid;
  49
  50         bool gid_set:1;
  51
  52         /* When set the group with the specified gid must exist
  53          * and the check if a uid clashes with the gid is skipped.
  54          */
  55         bool id_set_strict:1;
  56
  57         bool uid_set:1;
  58
  59         bool todo_user:1;
  60         bool todo_group:1;
  61 } Item;
  62
  63 static char *arg_root = NULL;
  64 static const char *arg_replace = NULL;
  65 static bool arg_inline = false;
  66
  67 static const char conf_file_dirs[] = CONF_PATHS_NULSTR("sysusers.d");
  68
  69 static OrderedHashmap *users = NULL, *groups = NULL;
  70 static OrderedHashmap *todo_uids = NULL, *todo_gids = NULL;
  71 static OrderedHashmap *members = NULL;
  72
  73 static Hashmap *database_uid = NULL, *database_user = NULL;
  74 static Hashmap *database_gid = NULL, *database_group = NULL;
  75
  76 static uid_t search_uid = UID_INVALID;
  77 static UidRange *uid_range = NULL;
  78 static unsigned n_uid_range = 0;
  79
  80 static int load_user_database(void) {
  81         _cleanup_fclose_ FILE *f = NULL;
  82         const char *passwd_path;
  83         struct passwd *pw;
  84         int r;
  85
  86         passwd_path = prefix_roota(arg_root, "/etc/passwd");
  87         f = fopen(passwd_path, "re");
  88         if (!f)
  89                 return errno == ENOENT ? 0 : -errno;
  90
  91         r = hashmap_ensure_allocated(&database_user, &string_hash_ops);
  92         if (r < 0)
  93                 return r;
  94
  95         r = hashmap_ensure_allocated(&database_uid, NULL);
  96         if (r < 0)
  97                 return r;
  98
  99         while ((r = fgetpwent_sane(f, &pw)) > 0) {
 100                 char *n;
 101                 int k, q;
 102
 103                 n = strdup(pw->pw_name);
 104                 if (!n)
 105                         return -ENOMEM;
 106
 107                 k = hashmap_put(database_user, n, UID_TO_PTR(pw->pw_uid));
 108                 if (k < 0 && k != -EEXIST) {
 109                         free(n);
 110                         return k;
 111                 }
 112
 113                 q = hashmap_put(database_uid, UID_TO_PTR(pw->pw_uid), n);
 114                 if (q < 0 && q != -EEXIST) {
 115                         if (k < 0)
 116                                 free(n);
 117                         return q;
 118                 }
 119
 120                 if (q < 0 && k < 0)
 121                         free(n);
 122         }
 123         return r;
 124 }
 125
 126 static int load_group_database(void) {
 127         _cleanup_fclose_ FILE *f = NULL;
 128         const char *group_path;
 129         struct group *gr;
 130         int r;
 131
 132         group_path = prefix_roota(arg_root, "/etc/group");
 133         f = fopen(group_path, "re");
 134         if (!f)
 135                 return errno == ENOENT ? 0 : -errno;
 136
 137         r = hashmap_ensure_allocated(&database_group, &string_hash_ops);
 138         if (r < 0)
 139                 return r;
 140
 141         r = hashmap_ensure_allocated(&database_gid, NULL);
 142         if (r < 0)
 143                 return r;
 144
 145         errno = 0;
 146         while ((gr = fgetgrent(f))) {
 147                 char *n;
 148                 int k, q;
 149
 150                 n = strdup(gr->gr_name);
 151                 if (!n)
 152                         return -ENOMEM;
 153
 154                 k = hashmap_put(database_group, n, GID_TO_PTR(gr->gr_gid));
 155                 if (k < 0 && k != -EEXIST) {
 156                         free(n);
 157                         return k;
 158                 }
 159
 160                 q = hashmap_put(database_gid, GID_TO_PTR(gr->gr_gid), n);
 161                 if (q < 0 && q != -EEXIST) {
 162                         if (k < 0)
 163                                 free(n);
 164                         return q;
 165                 }
 166
 167                 if (q < 0 && k < 0)
 168                         free(n);
 169
 170                 errno = 0;
 171         }
 172         if (!IN_SET(errno, 0, ENOENT))
 173                 return -errno;
 174
 175         return 0;
 176 }
 177
 178 static int make_backup(const char *target, const char *x) {
 179         _cleanup_close_ int src = -1;
 180         _cleanup_fclose_ FILE *dst = NULL;
 181         _cleanup_free_ char *temp = NULL;
 182         char *backup;
 183         struct timespec ts[2];
 184         struct stat st;
 185         int r;
 186
 187         src = open(x, O_RDONLY|O_CLOEXEC|O_NOCTTY);
 188         if (src < 0) {
 189                 if (errno == ENOENT) /* No backup necessary... */
 190                         return 0;
 191
 192                 return -errno;
 193         }
 194
 195         if (fstat(src, &st) < 0)
 196                 return -errno;
 197
 198         r = fopen_temporary_label(target, x, &dst, &temp);
 199         if (r < 0)
 200                 return r;
 201
 202         r = copy_bytes(src, fileno(dst), (uint64_t) -1, COPY_REFLINK);
 203         if (r < 0)
 204                 goto fail;
 205
 206         /* Don't fail on chmod() or chown(). If it stays owned by us
 207          * and/or unreadable by others, then it isn't too bad... */
 208
 209         backup = strjoina(x, "-");
 210
 211         /* Copy over the access mask */
 212         if (fchmod(fileno(dst), st.st_mode & 07777) < 0)
 213                 log_warning_errno(errno, "Failed to change mode on %s: %m", backup);
 214
 215         if (fchown(fileno(dst), st.st_uid, st.st_gid)< 0)
 216                 log_warning_errno(errno, "Failed to change ownership of %s: %m", backup);
 217
 218         ts[0] = st.st_atim;
 219         ts[1] = st.st_mtim;
 220         if (futimens(fileno(dst), ts) < 0)
 221                 log_warning_errno(errno, "Failed to fix access and modification time of %s: %m", backup);
 222
 223         r = fflush_sync_and_check(dst);
 224         if (r < 0)
 225                 goto fail;
 226
 227         if (rename(temp, backup) < 0) {
 228                 r = -errno;
 229                 goto fail;
 230         }
 231
 232         return 0;
 233
 234 fail:
 235         unlink(temp);
 236         return r;
 237 }
 238
 239 static int putgrent_with_members(const struct group *gr, FILE *group) {
 240         char **a;
 241
 242         assert(gr);
 243         assert(group);
 244
 245         a = ordered_hashmap_get(members, gr->gr_name);
 246         if (a) {
 247                 _cleanup_strv_free_ char **l = NULL;
 248                 bool added = false;
 249                 char **i;
 250
 251                 l = strv_copy(gr->gr_mem);
 252                 if (!l)
 253                         return -ENOMEM;
 254
 255                 STRV_FOREACH(i, a) {
 256                         if (strv_find(l, *i))
 257                                 continue;
 258
 259                         if (strv_extend(&l, *i) < 0)
 260                                 return -ENOMEM;
 261
 262                         added = true;
 263                 }
 264
 265                 if (added) {
 266                         struct group t;
 267                         int r;
 268
 269                         strv_uniq(l);
 270                         strv_sort(l);
 271
 272                         t = *gr;
 273                         t.gr_mem = l;
 274
 275                         r = putgrent_sane(&t, group);
 276                         return r < 0 ? r : 1;
 277                 }
 278         }
 279
 280         return putgrent_sane(gr, group);
 281 }
 282
 283 #if ENABLE_GSHADOW
 284 static int putsgent_with_members(const struct sgrp *sg, FILE *gshadow) {
 285         char **a;
 286
 287         assert(sg);
 288         assert(gshadow);
 289
 290         a = ordered_hashmap_get(members, sg->sg_namp);
 291         if (a) {
 292                 _cleanup_strv_free_ char **l = NULL;
 293                 bool added = false;
 294                 char **i;
 295
 296                 l = strv_copy(sg->sg_mem);
 297                 if (!l)
 298                         return -ENOMEM;
 299
 300                 STRV_FOREACH(i, a) {
 301                         if (strv_find(l, *i))
 302                                 continue;
 303
 304                         if (strv_extend(&l, *i) < 0)
 305                                 return -ENOMEM;
 306
 307                         added = true;
 308                 }
 309
 310                 if (added) {
 311                         struct sgrp t;
 312                         int r;
 313
 314                         strv_uniq(l);
 315                         strv_sort(l);
 316
 317                         t = *sg;
 318                         t.sg_mem = l;
 319
 320                         r = putsgent_sane(&t, gshadow);
 321                         return r < 0 ? r : 1;
 322                 }
 323         }
 324
 325         return putsgent_sane(sg, gshadow);
 326 }
 327 #endif
 328
 329 static int sync_rights(FILE *from, FILE *to) {
 330         struct stat st;
 331
 332         if (fstat(fileno(from), &st) < 0)
 333                 return -errno;
 334
 335         if (fchmod(fileno(to), st.st_mode & 07777) < 0)
 336                 return -errno;
 337
 338         if (fchown(fileno(to), st.st_uid, st.st_gid) < 0)
 339                 return -errno;
 340
 341         return 0;
 342 }
 343
 344 static int rename_and_apply_smack(const char *temp_path, const char *dest_path) {
 345         int r = 0;
 346         if (rename(temp_path, dest_path) < 0)
 347                 return -errno;
 348
 349 #ifdef SMACK_RUN_LABEL
 350         r = mac_smack_apply(dest_path, SMACK_ATTR_ACCESS, SMACK_FLOOR_LABEL);
 351         if (r < 0)
 352                 return r;
 353 #endif
 354         return r;
 355 }
 356
 357 static const char* default_shell(uid_t uid) {
 358         return uid == 0 ? "/bin/sh" : "/sbin/nologin";
 359 }
 360
 361 static int write_temporary_passwd(const char *passwd_path, FILE **tmpfile, char **tmpfile_path) {
 362         _cleanup_fclose_ FILE *original = NULL, *passwd = NULL;
 363         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL;
 364         struct passwd *pw = NULL;
 365         Iterator iterator;
 366         Item *i;
 367         int r;
 368
 369         if (ordered_hashmap_size(todo_uids) == 0)
 370                 return 0;
 371
 372         r = fopen_temporary_label("/etc/passwd", passwd_path, &passwd, &passwd_tmp);
 373         if (r < 0)
 374                 return r;
 375
 376         original = fopen(passwd_path, "re");
 377         if (original) {
 378
 379                 r = sync_rights(original, passwd);
 380                 if (r < 0)
 381                         return r;
 382
 383                 while ((r = fgetpwent_sane(original, &pw)) > 0) {
 384
 385                         i = ordered_hashmap_get(users, pw->pw_name);
 386                         if (i && i->todo_user) {
 387                                 log_error("%s: User \"%s\" already exists.", passwd_path, pw->pw_name);
 388                                 return -EEXIST;
 389                         }
 390
 391                         if (ordered_hashmap_contains(todo_uids, UID_TO_PTR(pw->pw_uid))) {
 392                                 log_error("%s: Detected collision for UID " UID_FMT ".", passwd_path, pw->pw_uid);
 393                                 return -EEXIST;
 394                         }
 395
 396                         /* Make sure we keep the NIS entries (if any) at the end. */
 397                         if (IN_SET(pw->pw_name[0], '+', '-'))
 398                                 break;
 399
 400                         r = putpwent_sane(pw, passwd);
 401                         if (r < 0)
 402                                 return r;
 403                 }
 404                 if (r < 0)
 405                         return r;
 406
 407         } else {
 408                 if (errno != ENOENT)
 409                         return -errno;
 410                 if (fchmod(fileno(passwd), 0644) < 0)
 411                         return -errno;
 412         }
 413
 414         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 415                 struct passwd n = {
 416                         .pw_name = i->name,
 417                         .pw_uid = i->uid,
 418                         .pw_gid = i->gid,
 419                         .pw_gecos = i->description,
 420
 421                         /* "x" means the password is stored in the shadow file */
 422                         .pw_passwd = (char*) "x",
 423
 424                         /* We default to the root directory as home */
 425                         .pw_dir = i->home ? i->home : (char*) "/",
 426
 427                         /* Initialize the shell to nologin, with one exception:
 428                          * for root we patch in something special */
 429                         .pw_shell = i->shell ?: (char*) default_shell(i->uid),
 430                 };
 431
 432                 r = putpwent_sane(&n, passwd);
 433                 if (r < 0)
 434                         return r;
 435         }
 436
 437         /* Append the remaining NIS entries if any */
 438         while (pw) {
 439                 r = putpwent_sane(pw, passwd);
 440                 if (r < 0)
 441                         return r;
 442
 443                 r = fgetpwent_sane(original, &pw);
 444                 if (r < 0)
 445                         return r;
 446                 if (r == 0)
 447                         break;
 448         }
 449
 450         r = fflush_and_check(passwd);
 451         if (r < 0)
 452                 return r;
 453
 454         *tmpfile = TAKE_PTR(passwd);
 455         *tmpfile_path = TAKE_PTR(passwd_tmp);
 456
 457         return 0;
 458 }
 459
 460 static int write_temporary_shadow(const char *shadow_path, FILE **tmpfile, char **tmpfile_path) {
 461         _cleanup_fclose_ FILE *original = NULL, *shadow = NULL;
 462         _cleanup_(unlink_and_freep) char *shadow_tmp = NULL;
 463         struct spwd *sp = NULL;
 464         Iterator iterator;
 465         long lstchg;
 466         Item *i;
 467         int r;
 468
 469         if (ordered_hashmap_size(todo_uids) == 0)
 470                 return 0;
 471
 472         r = fopen_temporary_label("/etc/shadow", shadow_path, &shadow, &shadow_tmp);
 473         if (r < 0)
 474                 return r;
 475
 476         lstchg = (long) (now(CLOCK_REALTIME) / USEC_PER_DAY);
 477
 478         original = fopen(shadow_path, "re");
 479         if (original) {
 480
 481                 r = sync_rights(original, shadow);
 482                 if (r < 0)
 483                         return r;
 484
 485                 while ((r = fgetspent_sane(original, &sp)) > 0) {
 486
 487                         i = ordered_hashmap_get(users, sp->sp_namp);
 488                         if (i && i->todo_user) {
 489                                 /* we will update the existing entry */
 490                                 sp->sp_lstchg = lstchg;
 491
 492                                 /* only the /etc/shadow stage is left, so we can
 493                                  * safely remove the item from the todo set */
 494                                 i->todo_user = false;
 495                                 ordered_hashmap_remove(todo_uids, UID_TO_PTR(i->uid));
 496                         }
 497
 498                         /* Make sure we keep the NIS entries (if any) at the end. */
 499                         if (IN_SET(sp->sp_namp[0], '+', '-'))
 500                                 break;
 501
 502                         r = putspent_sane(sp, shadow);
 503                         if (r < 0)
 504                                 return r;
 505                 }
 506                 if (r < 0)
 507                         return r;
 508
 509         } else {
 510                 if (errno != ENOENT)
 511                         return -errno;
 512                 if (fchmod(fileno(shadow), 0000) < 0)
 513                         return -errno;
 514         }
 515
 516         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 517                 struct spwd n = {
 518                         .sp_namp = i->name,
 519                         .sp_pwdp = (char*) "!!",
 520                         .sp_lstchg = lstchg,
 521                         .sp_min = -1,
 522                         .sp_max = -1,
 523                         .sp_warn = -1,
 524                         .sp_inact = -1,
 525                         .sp_expire = -1,
 526                         .sp_flag = (unsigned long) -1, /* this appears to be what everybody does ... */
 527                 };
 528
 529                 r = putspent_sane(&n, shadow);
 530                 if (r < 0)
 531                         return r;
 532         }
 533
 534         /* Append the remaining NIS entries if any */
 535         while (sp) {
 536                 r = putspent_sane(sp, shadow);
 537                 if (r < 0)
 538                         return r;
 539
 540                 r = fgetspent_sane(original, &sp);
 541                 if (r < 0)
 542                         return r;
 543                 if (r == 0)
 544                         break;
 545         }
 546         if (!IN_SET(errno, 0, ENOENT))
 547                 return -errno;
 548
 549         r = fflush_sync_and_check(shadow);
 550         if (r < 0)
 551                 return r;
 552
 553         *tmpfile = TAKE_PTR(shadow);
 554         *tmpfile_path = TAKE_PTR(shadow_tmp);
 555
 556         return 0;
 557 }
 558
 559 static int write_temporary_group(const char *group_path, FILE **tmpfile, char **tmpfile_path) {
 560         _cleanup_fclose_ FILE *original = NULL, *group = NULL;
 561         _cleanup_(unlink_and_freep) char *group_tmp = NULL;
 562         bool group_changed = false;
 563         struct group *gr = NULL;
 564         Iterator iterator;
 565         Item *i;
 566         int r;
 567
 568         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 569                 return 0;
 570
 571         r = fopen_temporary_label("/etc/group", group_path, &group, &group_tmp);
 572         if (r < 0)
 573                 return r;
 574
 575         original = fopen(group_path, "re");
 576         if (original) {
 577
 578                 r = sync_rights(original, group);
 579                 if (r < 0)
 580                         return r;
 581
 582                 while ((r = fgetgrent_sane(original, &gr)) > 0) {
 583                         /* Safety checks against name and GID collisions. Normally,
 584                          * this should be unnecessary, but given that we look at the
 585                          * entries anyway here, let's make an extra verification
 586                          * step that we don't generate duplicate entries. */
 587
 588                         i = ordered_hashmap_get(groups, gr->gr_name);
 589                         if (i && i->todo_group) {
 590                                 log_error("%s: Group \"%s\" already exists.", group_path, gr->gr_name);
 591                                 return -EEXIST;
 592                         }
 593
 594                         if (ordered_hashmap_contains(todo_gids, GID_TO_PTR(gr->gr_gid))) {
 595                                 log_error("%s: Detected collision for GID " GID_FMT ".", group_path, gr->gr_gid);
 596                                 return  -EEXIST;
 597                         }
 598
 599                         /* Make sure we keep the NIS entries (if any) at the end. */
 600                         if (IN_SET(gr->gr_name[0], '+', '-'))
 601                                 break;
 602
 603                         r = putgrent_with_members(gr, group);
 604                         if (r < 0)
 605                                 return r;
 606                         if (r > 0)
 607                                 group_changed = true;
 608                 }
 609                 if (r < 0)
 610                         return r;
 611
 612         } else {
 613                 if (errno != ENOENT)
 614                         return -errno;
 615                 if (fchmod(fileno(group), 0644) < 0)
 616                         return -errno;
 617         }
 618
 619         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 620                 struct group n = {
 621                         .gr_name = i->name,
 622                         .gr_gid = i->gid,
 623                         .gr_passwd = (char*) "x",
 624                 };
 625
 626                 r = putgrent_with_members(&n, group);
 627                 if (r < 0)
 628                         return r;
 629
 630                 group_changed = true;
 631         }
 632
 633         /* Append the remaining NIS entries if any */
 634         while (gr) {
 635                 r = putgrent_sane(gr, group);
 636                 if (r < 0)
 637                         return r;
 638
 639                 r = fgetgrent_sane(original, &gr);
 640                 if (r < 0)
 641                         return r;
 642                 if (r == 0)
 643                         break;
 644         }
 645
 646         r = fflush_sync_and_check(group);
 647         if (r < 0)
 648                 return r;
 649
 650         if (group_changed) {
 651                 *tmpfile = TAKE_PTR(group);
 652                 *tmpfile_path = TAKE_PTR(group_tmp);
 653         }
 654         return 0;
 655 }
 656
 657 static int write_temporary_gshadow(const char * gshadow_path, FILE **tmpfile, char **tmpfile_path) {
 658 #if ENABLE_GSHADOW
 659         _cleanup_fclose_ FILE *original = NULL, *gshadow = NULL;
 660         _cleanup_(unlink_and_freep) char *gshadow_tmp = NULL;
 661         bool group_changed = false;
 662         Iterator iterator;
 663         Item *i;
 664         int r;
 665
 666         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 667                 return 0;
 668
 669         r = fopen_temporary_label("/etc/gshadow", gshadow_path, &gshadow, &gshadow_tmp);
 670         if (r < 0)
 671                 return r;
 672
 673         original = fopen(gshadow_path, "re");
 674         if (original) {
 675                 struct sgrp *sg;
 676
 677                 r = sync_rights(original, gshadow);
 678                 if (r < 0)
 679                         return r;
 680
 681                 while ((r = fgetsgent_sane(original, &sg)) > 0) {
 682
 683                         i = ordered_hashmap_get(groups, sg->sg_namp);
 684                         if (i && i->todo_group) {
 685                                 log_error("%s: Group \"%s\" already exists.", gshadow_path, sg->sg_namp);
 686                                 return -EEXIST;
 687                         }
 688
 689                         r = putsgent_with_members(sg, gshadow);
 690                         if (r < 0)
 691                                 return r;
 692                         if (r > 0)
 693                                 group_changed = true;
 694                 }
 695                 if (r < 0)
 696                         return r;
 697
 698         } else {
 699                 if (errno != ENOENT)
 700                         return -errno;
 701                 if (fchmod(fileno(gshadow), 0000) < 0)
 702                         return -errno;
 703         }
 704
 705         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 706                 struct sgrp n = {
 707                         .sg_namp = i->name,
 708                         .sg_passwd = (char*) "!!",
 709                 };
 710
 711                 r = putsgent_with_members(&n, gshadow);
 712                 if (r < 0)
 713                         return r;
 714
 715                 group_changed = true;
 716         }
 717
 718         r = fflush_sync_and_check(gshadow);
 719         if (r < 0)
 720                 return r;
 721
 722         if (group_changed) {
 723                 *tmpfile = TAKE_PTR(gshadow);
 724                 *tmpfile_path = TAKE_PTR(gshadow_tmp);
 725         }
 726         return 0;
 727 #else
 728         return 0;
 729 #endif
 730 }
 731
 732 static int write_files(void) {
 733         _cleanup_fclose_ FILE *passwd = NULL, *group = NULL, *shadow = NULL, *gshadow = NULL;
 734         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL, *group_tmp = NULL, *shadow_tmp = NULL, *gshadow_tmp = NULL;
 735         const char *passwd_path = NULL, *group_path = NULL, *shadow_path = NULL, *gshadow_path = NULL;
 736         int r;
 737
 738         passwd_path = prefix_roota(arg_root, "/etc/passwd");
 739         shadow_path = prefix_roota(arg_root, "/etc/shadow");
 740         group_path = prefix_roota(arg_root, "/etc/group");
 741         gshadow_path = prefix_roota(arg_root, "/etc/gshadow");
 742
 743         r = write_temporary_group(group_path, &group, &group_tmp);
 744         if (r < 0)
 745                 return r;
 746
 747         r = write_temporary_gshadow(gshadow_path, &gshadow, &gshadow_tmp);
 748         if (r < 0)
 749                 return r;
 750
 751         r = write_temporary_passwd(passwd_path, &passwd, &passwd_tmp);
 752         if (r < 0)
 753                 return r;
 754
 755         r = write_temporary_shadow(shadow_path, &shadow, &shadow_tmp);
 756         if (r < 0)
 757                 return r;
 758
 759         /* Make a backup of the old files */
 760         if (group) {
 761                 r = make_backup("/etc/group", group_path);
 762                 if (r < 0)
 763                         return r;
 764         }
 765         if (gshadow) {
 766                 r = make_backup("/etc/gshadow", gshadow_path);
 767                 if (r < 0)
 768                         return r;
 769         }
 770
 771         if (passwd) {
 772                 r = make_backup("/etc/passwd", passwd_path);
 773                 if (r < 0)
 774                         return r;
 775         }
 776         if (shadow) {
 777                 r = make_backup("/etc/shadow", shadow_path);
 778                 if (r < 0)
 779                         return r;
 780         }
 781
 782         /* And make the new files count */
 783         if (group) {
 784                 r = rename_and_apply_smack(group_tmp, group_path);
 785                 if (r < 0)
 786                         return r;
 787
 788                 group_tmp = mfree(group_tmp);
 789         }
 790         if (gshadow) {
 791                 r = rename_and_apply_smack(gshadow_tmp, gshadow_path);
 792                 if (r < 0)
 793                         return r;
 794
 795                 gshadow_tmp = mfree(gshadow_tmp);
 796         }
 797
 798         if (passwd) {
 799                 r = rename_and_apply_smack(passwd_tmp, passwd_path);
 800                 if (r < 0)
 801                         return r;
 802
 803                 passwd_tmp = mfree(passwd_tmp);
 804         }
 805         if (shadow) {
 806                 r = rename_and_apply_smack(shadow_tmp, shadow_path);
 807                 if (r < 0)
 808                         return r;
 809
 810                 shadow_tmp = mfree(shadow_tmp);
 811         }
 812
 813         return 0;
 814 }
 815
 816 static int uid_is_ok(uid_t uid, const char *name, bool check_with_gid) {
 817         struct passwd *p;
 818         struct group *g;
 819         const char *n;
 820         Item *i;
 821
 822         /* Let's see if we already have assigned the UID a second time */
 823         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(uid)))
 824                 return 0;
 825
 826         /* Try to avoid using uids that are already used by a group
 827          * that doesn't have the same name as our new user. */
 828         if (check_with_gid) {
 829                 i = ordered_hashmap_get(todo_gids, GID_TO_PTR(uid));
 830                 if (i && !streq(i->name, name))
 831                         return 0;
 832         }
 833
 834         /* Let's check the files directly */
 835         if (hashmap_contains(database_uid, UID_TO_PTR(uid)))
 836                 return 0;
 837
 838         if (check_with_gid) {
 839                 n = hashmap_get(database_gid, GID_TO_PTR(uid));
 840                 if (n && !streq(n, name))
 841                         return 0;
 842         }
 843
 844         /* Let's also check via NSS, to avoid UID clashes over LDAP and such, just in case */
 845         if (!arg_root) {
 846                 errno = 0;
 847                 p = getpwuid(uid);
 848                 if (p)
 849                         return 0;
 850                 if (!IN_SET(errno, 0, ENOENT))
 851                         return -errno;
 852
 853                 if (check_with_gid) {
 854                         errno = 0;
 855                         g = getgrgid((gid_t) uid);
 856                         if (g) {
 857                                 if (!streq(g->gr_name, name))
 858                                         return 0;
 859                         } else if (!IN_SET(errno, 0, ENOENT))
 860                                 return -errno;
 861                 }
 862         }
 863
 864         return 1;
 865 }
 866
 867 static int root_stat(const char *p, struct stat *st) {
 868         const char *fix;
 869
 870         fix = prefix_roota(arg_root, p);
 871         if (stat(fix, st) < 0)
 872                 return -errno;
 873
 874         return 0;
 875 }
 876
 877 static int read_id_from_file(Item *i, uid_t *_uid, gid_t *_gid) {
 878         struct stat st;
 879         bool found_uid = false, found_gid = false;
 880         uid_t uid = 0;
 881         gid_t gid = 0;
 882
 883         assert(i);
 884
 885         /* First, try to get the gid directly */
 886         if (_gid && i->gid_path && root_stat(i->gid_path, &st) >= 0) {
 887                 gid = st.st_gid;
 888                 found_gid = true;
 889         }
 890
 891         /* Then, try to get the uid directly */
 892         if ((_uid || (_gid && !found_gid))
 893             && i->uid_path
 894             && root_stat(i->uid_path, &st) >= 0) {
 895
 896                 uid = st.st_uid;
 897                 found_uid = true;
 898
 899                 /* If we need the gid, but had no success yet, also derive it from the uid path */
 900                 if (_gid && !found_gid) {
 901                         gid = st.st_gid;
 902                         found_gid = true;
 903                 }
 904         }
 905
 906         /* If that didn't work yet, then let's reuse the gid as uid */
 907         if (_uid && !found_uid && i->gid_path) {
 908
 909                 if (found_gid) {
 910                         uid = (uid_t) gid;
 911                         found_uid = true;
 912                 } else if (root_stat(i->gid_path, &st) >= 0) {
 913                         uid = (uid_t) st.st_gid;
 914                         found_uid = true;
 915                 }
 916         }
 917
 918         if (_uid) {
 919                 if (!found_uid)
 920                         return 0;
 921
 922                 *_uid = uid;
 923         }
 924
 925         if (_gid) {
 926                 if (!found_gid)
 927                         return 0;
 928
 929                 *_gid = gid;
 930         }
 931
 932         return 1;
 933 }
 934
 935 static int add_user(Item *i) {
 936         void *z;
 937         int r;
 938
 939         assert(i);
 940
 941         /* Check the database directly */
 942         z = hashmap_get(database_user, i->name);
 943         if (z) {
 944                 log_debug("User %s already exists.", i->name);
 945                 i->uid = PTR_TO_UID(z);
 946                 i->uid_set = true;
 947                 return 0;
 948         }
 949
 950         if (!arg_root) {
 951                 struct passwd *p;
 952
 953                 /* Also check NSS */
 954                 errno = 0;
 955                 p = getpwnam(i->name);
 956                 if (p) {
 957                         log_debug("User %s already exists.", i->name);
 958                         i->uid = p->pw_uid;
 959                         i->uid_set = true;
 960
 961                         r = free_and_strdup(&i->description, p->pw_gecos);
 962                         if (r < 0)
 963                                 return log_oom();
 964
 965                         return 0;
 966                 }
 967                 if (!IN_SET(errno, 0, ENOENT))
 968                         return log_error_errno(errno, "Failed to check if user %s already exists: %m", i->name);
 969         }
 970
 971         /* Try to use the suggested numeric uid */
 972         if (i->uid_set) {
 973                 r = uid_is_ok(i->uid, i->name, !i->id_set_strict);
 974                 if (r < 0)
 975                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
 976                 if (r == 0) {
 977                         log_debug("Suggested user ID " UID_FMT " for %s already used.", i->uid, i->name);
 978                         i->uid_set = false;
 979                 }
 980         }
 981
 982         /* If that didn't work, try to read it from the specified path */
 983         if (!i->uid_set) {
 984                 uid_t c;
 985
 986                 if (read_id_from_file(i, &c, NULL) > 0) {
 987
 988                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
 989                                 log_debug("User ID " UID_FMT " of file not suitable for %s.", c, i->name);
 990                         else {
 991                                 r = uid_is_ok(c, i->name, true);
 992                                 if (r < 0)
 993                                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
 994                                 else if (r > 0) {
 995                                         i->uid = c;
 996                                         i->uid_set = true;
 997                                 } else
 998                                         log_debug("User ID " UID_FMT " of file for %s is already used.", c, i->name);
 999                         }
1000                 }
1001         }
1002
1003         /* Otherwise, try to reuse the group ID */
1004         if (!i->uid_set && i->gid_set) {
1005                 r = uid_is_ok((uid_t) i->gid, i->name, true);
1006                 if (r < 0)
1007                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1008                 if (r > 0) {
1009                         i->uid = (uid_t) i->gid;
1010                         i->uid_set = true;
1011                 }
1012         }
1013
1014         /* And if that didn't work either, let's try to find a free one */
1015         if (!i->uid_set) {
1016                 for (;;) {
1017                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1018                         if (r < 0) {
1019                                 log_error("No free user ID available for %s.", i->name);
1020                                 return r;
1021                         }
1022
1023                         r = uid_is_ok(search_uid, i->name, true);
1024                         if (r < 0)
1025                                 return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1026                         else if (r > 0)
1027                                 break;
1028                 }
1029
1030                 i->uid_set = true;
1031                 i->uid = search_uid;
1032         }
1033
1034         r = ordered_hashmap_ensure_allocated(&todo_uids, NULL);
1035         if (r < 0)
1036                 return log_oom();
1037
1038         r = ordered_hashmap_put(todo_uids, UID_TO_PTR(i->uid), i);
1039         if (r < 0)
1040                 return log_oom();
1041
1042         i->todo_user = true;
1043         log_info("Creating user %s (%s) with uid " UID_FMT " and gid " GID_FMT ".", i->name, strna(i->description), i->uid, i->gid);
1044
1045         return 0;
1046 }
1047
1048 static int gid_is_ok(gid_t gid) {
1049         struct group *g;
1050         struct passwd *p;
1051
1052         if (ordered_hashmap_get(todo_gids, GID_TO_PTR(gid)))
1053                 return 0;
1054
1055         /* Avoid reusing gids that are already used by a different user */
1056         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(gid)))
1057                 return 0;
1058
1059         if (hashmap_contains(database_gid, GID_TO_PTR(gid)))
1060                 return 0;
1061
1062         if (hashmap_contains(database_uid, UID_TO_PTR(gid)))
1063                 return 0;
1064
1065         if (!arg_root) {
1066                 errno = 0;
1067                 g = getgrgid(gid);
1068                 if (g)
1069                         return 0;
1070                 if (!IN_SET(errno, 0, ENOENT))
1071                         return -errno;
1072
1073                 errno = 0;
1074                 p = getpwuid((uid_t) gid);
1075                 if (p)
1076                         return 0;
1077                 if (!IN_SET(errno, 0, ENOENT))
1078                         return -errno;
1079         }
1080
1081         return 1;
1082 }
1083
1084 static int add_group(Item *i) {
1085         void *z;
1086         int r;
1087
1088         assert(i);
1089
1090         /* Check the database directly */
1091         z = hashmap_get(database_group, i->name);
1092         if (z) {
1093                 log_debug("Group %s already exists.", i->name);
1094                 i->gid = PTR_TO_GID(z);
1095                 i->gid_set = true;
1096                 return 0;
1097         }
1098
1099         /* Also check NSS */
1100         if (!arg_root) {
1101                 struct group *g;
1102
1103                 errno = 0;
1104                 g = getgrnam(i->name);
1105                 if (g) {
1106                         log_debug("Group %s already exists.", i->name);
1107                         i->gid = g->gr_gid;
1108                         i->gid_set = true;
1109                         return 0;
1110                 }
1111                 if (!IN_SET(errno, 0, ENOENT))
1112                         return log_error_errno(errno, "Failed to check if group %s already exists: %m", i->name);
1113         }
1114
1115         /* Try to use the suggested numeric gid */
1116         if (i->gid_set) {
1117                 r = gid_is_ok(i->gid);
1118                 if (r < 0)
1119                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1120                 if (i->id_set_strict) {
1121                         /* If we require the gid to already exist we can return here:
1122                          * r > 0: means the gid does not exist -> fail
1123                          * r == 0: means the gid exists -> nothing more to do.
1124                          */
1125                         if (r > 0) {
1126                                 log_error("Failed to create %s: please create GID %d", i->name, i->gid);
1127                                 return -EINVAL;
1128                         }
1129                         if (r == 0)
1130                                 return 0;
1131                 }
1132                 if (r == 0) {
1133                         log_debug("Suggested group ID " GID_FMT " for %s already used.", i->gid, i->name);
1134                         i->gid_set = false;
1135                 }
1136         }
1137
1138         /* Try to reuse the numeric uid, if there's one */
1139         if (!i->gid_set && i->uid_set) {
1140                 r = gid_is_ok((gid_t) i->uid);
1141                 if (r < 0)
1142                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1143                 if (r > 0) {
1144                         i->gid = (gid_t) i->uid;
1145                         i->gid_set = true;
1146                 }
1147         }
1148
1149         /* If that didn't work, try to read it from the specified path */
1150         if (!i->gid_set) {
1151                 gid_t c;
1152
1153                 if (read_id_from_file(i, NULL, &c) > 0) {
1154
1155                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
1156                                 log_debug("Group ID " GID_FMT " of file not suitable for %s.", c, i->name);
1157                         else {
1158                                 r = gid_is_ok(c);
1159                                 if (r < 0)
1160                                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1161                                 else if (r > 0) {
1162                                         i->gid = c;
1163                                         i->gid_set = true;
1164                                 } else
1165                                         log_debug("Group ID " GID_FMT " of file for %s already used.", c, i->name);
1166                         }
1167                 }
1168         }
1169
1170         /* And if that didn't work either, let's try to find a free one */
1171         if (!i->gid_set) {
1172                 for (;;) {
1173                         /* We look for new GIDs in the UID pool! */
1174                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1175                         if (r < 0) {
1176                                 log_error("No free group ID available for %s.", i->name);
1177                                 return r;
1178                         }
1179
1180                         r = gid_is_ok(search_uid);
1181                         if (r < 0)
1182                                 return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1183                         else if (r > 0)
1184                                 break;
1185                 }
1186
1187                 i->gid_set = true;
1188                 i->gid = search_uid;
1189         }
1190
1191         r = ordered_hashmap_ensure_allocated(&todo_gids, NULL);
1192         if (r < 0)
1193                 return log_oom();
1194
1195         r = ordered_hashmap_put(todo_gids, GID_TO_PTR(i->gid), i);
1196         if (r < 0)
1197                 return log_oom();
1198
1199         i->todo_group = true;
1200         log_info("Creating group %s with gid " GID_FMT ".", i->name, i->gid);
1201
1202         return 0;
1203 }
1204
1205 static int process_item(Item *i) {
1206         int r;
1207
1208         assert(i);
1209
1210         switch (i->type) {
1211
1212         case ADD_USER: {
1213                 Item *j;
1214
1215                 j = ordered_hashmap_get(groups, i->name);
1216                 if (j && j->todo_group) {
1217                         /* When the group with the same name is already in queue,
1218                          * use the information about the group and do not create
1219                          * duplicated group entry. */
1220                         i->gid_set = j->gid_set;
1221                         i->gid = j->gid;
1222                         i->id_set_strict = true;
1223                 } else {
1224                         r = add_group(i);
1225                         if (r < 0)
1226                                 return r;
1227                 }
1228
1229                 return add_user(i);
1230         }
1231
1232         case ADD_GROUP:
1233                 return add_group(i);
1234
1235         default:
1236                 assert_not_reached("Unknown item type");
1237         }
1238 }
1239
1240 static void item_free(Item *i) {
1241
1242         if (!i)
1243                 return;
1244
1245         free(i->name);
1246         free(i->uid_path);
1247         free(i->gid_path);
1248         free(i->description);
1249         free(i->home);
1250         free(i->shell);
1251         free(i);
1252 }
1253
1254 DEFINE_TRIVIAL_CLEANUP_FUNC(Item*, item_free);
1255
1256 static int add_implicit(void) {
1257         char *g, **l;
1258         Iterator iterator;
1259         int r;
1260
1261         /* Implicitly create additional users and groups, if they were listed in "m" lines */
1262         ORDERED_HASHMAP_FOREACH_KEY(l, g, members, iterator) {
1263                 char **m;
1264
1265                 STRV_FOREACH(m, l)
1266                         if (!ordered_hashmap_get(users, *m)) {
1267                                 _cleanup_(item_freep) Item *j = NULL;
1268
1269                                 r = ordered_hashmap_ensure_allocated(&users, &string_hash_ops);
1270                                 if (r < 0)
1271                                         return log_oom();
1272
1273                                 j = new0(Item, 1);
1274                                 if (!j)
1275                                         return log_oom();
1276
1277                                 j->type = ADD_USER;
1278                                 j->name = strdup(*m);
1279                                 if (!j->name)
1280                                         return log_oom();
1281
1282                                 r = ordered_hashmap_put(users, j->name, j);
1283                                 if (r < 0)
1284                                         return log_oom();
1285
1286                                 log_debug("Adding implicit user '%s' due to m line", j->name);
1287                                 j = NULL;
1288                         }
1289
1290                 if (!(ordered_hashmap_get(users, g) ||
1291                       ordered_hashmap_get(groups, g))) {
1292                         _cleanup_(item_freep) Item *j = NULL;
1293
1294                         r = ordered_hashmap_ensure_allocated(&groups, &string_hash_ops);
1295                         if (r < 0)
1296                                 return log_oom();
1297
1298                         j = new0(Item, 1);
1299                         if (!j)
1300                                 return log_oom();
1301
1302                         j->type = ADD_GROUP;
1303                         j->name = strdup(g);
1304                         if (!j->name)
1305                                 return log_oom();
1306
1307                         r = ordered_hashmap_put(groups, j->name, j);
1308                         if (r < 0)
1309                                 return log_oom();
1310
1311                         log_debug("Adding implicit group '%s' due to m line", j->name);
1312                         j = NULL;
1313                 }
1314         }
1315
1316         return 0;
1317 }
1318
1319 static bool item_equal(Item *a, Item *b) {
1320         assert(a);
1321         assert(b);
1322
1323         if (a->type != b->type)
1324                 return false;
1325
1326         if (!streq_ptr(a->name, b->name))
1327                 return false;
1328
1329         if (!streq_ptr(a->uid_path, b->uid_path))
1330                 return false;
1331
1332         if (!streq_ptr(a->gid_path, b->gid_path))
1333                 return false;
1334
1335         if (!streq_ptr(a->description, b->description))
1336                 return false;
1337
1338         if (a->uid_set != b->uid_set)
1339                 return false;
1340
1341         if (a->uid_set && a->uid != b->uid)
1342                 return false;
1343
1344         if (a->gid_set != b->gid_set)
1345                 return false;
1346
1347         if (a->gid_set && a->gid != b->gid)
1348                 return false;
1349
1350         if (!streq_ptr(a->home, b->home))
1351                 return false;
1352
1353         if (!streq_ptr(a->shell, b->shell))
1354                 return false;
1355
1356         return true;
1357 }
1358
1359 static int parse_line(const char *fname, unsigned line, const char *buffer) {
1360
1361         static const Specifier specifier_table[] = {
1362                 { 'm', specifier_machine_id, NULL },
1363                 { 'b', specifier_boot_id, NULL },
1364                 { 'H', specifier_host_name, NULL },
1365                 { 'v', specifier_kernel_release, NULL },
1366                 {}
1367         };
1368
1369         _cleanup_free_ char *action = NULL,
1370                 *name = NULL, *resolved_name = NULL,
1371                 *id = NULL, *resolved_id = NULL,
1372                 *description = NULL,
1373                 *home = NULL,
1374                 *shell, *resolved_shell = NULL;
1375         _cleanup_(item_freep) Item *i = NULL;
1376         Item *existing;
1377         OrderedHashmap *h;
1378         int r;
1379         const char *p;
1380
1381         assert(fname);
1382         assert(line >= 1);
1383         assert(buffer);
1384
1385         /* Parse columns */
1386         p = buffer;
1387         r = extract_many_words(&p, NULL, EXTRACT_QUOTES,
1388                                &action, &name, &id, &description, &home, &shell, NULL);
1389         if (r < 0) {
1390                 log_error("[%s:%u] Syntax error.", fname, line);
1391                 return r;
1392         }
1393         if (r < 2) {
1394                 log_error("[%s:%u] Missing action and name columns.", fname, line);
1395                 return -EINVAL;
1396         }
1397         if (!isempty(p)) {
1398                 log_error("[%s:%u] Trailing garbage.", fname, line);
1399                 return -EINVAL;
1400         }
1401
1402         /* Verify action */
1403         if (strlen(action) != 1) {
1404                 log_error("[%s:%u] Unknown modifier '%s'", fname, line, action);
1405                 return -EINVAL;
1406         }
1407
1408         if (!IN_SET(action[0], ADD_USER, ADD_GROUP, ADD_MEMBER, ADD_RANGE)) {
1409                 log_error("[%s:%u] Unknown command type '%c'.", fname, line, action[0]);
1410                 return -EBADMSG;
1411         }
1412
1413         /* Verify name */
1414         if (isempty(name) || streq(name, "-"))
1415                 name = mfree(name);
1416
1417         if (name) {
1418                 r = specifier_printf(name, specifier_table, NULL, &resolved_name);
1419                 if (r < 0) {
1420                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1421                         return r;
1422                 }
1423
1424                 if (!valid_user_group_name(resolved_name)) {
1425                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_name);
1426                         return -EINVAL;
1427                 }
1428         }
1429
1430         /* Verify id */
1431         if (isempty(id) || streq(id, "-"))
1432                 id = mfree(id);
1433
1434         if (id) {
1435                 r = specifier_printf(id, specifier_table, NULL, &resolved_id);
1436                 if (r < 0) {
1437                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1438                         return r;
1439                 }
1440         }
1441
1442         /* Verify description */
1443         if (isempty(description) || streq(description, "-"))
1444                 description = mfree(description);
1445
1446         if (description) {
1447                 if (!valid_gecos(description)) {
1448                         log_error("[%s:%u] '%s' is not a valid GECOS field.", fname, line, description);
1449                         return -EINVAL;
1450                 }
1451         }
1452
1453         /* Verify home */
1454         if (isempty(home) || streq(home, "-"))
1455                 home = mfree(home);
1456
1457         if (home) {
1458                 if (!valid_home(home)) {
1459                         log_error("[%s:%u] '%s' is not a valid home directory field.", fname, line, home);
1460                         return -EINVAL;
1461                 }
1462         }
1463
1464         /* Verify shell */
1465         if (isempty(shell) || streq(shell, "-"))
1466                 shell = mfree(shell);
1467
1468         if (shell) {
1469                 r = specifier_printf(shell, specifier_table, NULL, &resolved_shell);
1470                 if (r < 0) {
1471                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, shell);
1472                         return r;
1473                 }
1474
1475                 if (!valid_shell(resolved_shell)) {
1476                         log_error("[%s:%u] '%s' is not a valid login shell field.", fname, line, resolved_shell);
1477                         return -EINVAL;
1478                 }
1479         }
1480
1481         switch (action[0]) {
1482
1483         case ADD_RANGE:
1484                 if (resolved_name) {
1485                         log_error("[%s:%u] Lines of type 'r' don't take a name field.", fname, line);
1486                         return -EINVAL;
1487                 }
1488
1489                 if (!resolved_id) {
1490                         log_error("[%s:%u] Lines of type 'r' require a ID range in the third field.", fname, line);
1491                         return -EINVAL;
1492                 }
1493
1494                 if (description || home || shell) {
1495                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1496                                   fname, line, action[0],
1497                                   description ? "GECOS" : home ? "home directory" : "login shell");
1498                         return -EINVAL;
1499                 }
1500
1501                 r = uid_range_add_str(&uid_range, &n_uid_range, resolved_id);
1502                 if (r < 0) {
1503                         log_error("[%s:%u] Invalid UID range %s.", fname, line, resolved_id);
1504                         return -EINVAL;
1505                 }
1506
1507                 return 0;
1508
1509         case ADD_MEMBER: {
1510                 char **l;
1511
1512                 /* Try to extend an existing member or group item */
1513                 if (!name) {
1514                         log_error("[%s:%u] Lines of type 'm' require a user name in the second field.", fname, line);
1515                         return -EINVAL;
1516                 }
1517
1518                 if (!resolved_id) {
1519                         log_error("[%s:%u] Lines of type 'm' require a group name in the third field.", fname, line);
1520                         return -EINVAL;
1521                 }
1522
1523                 if (!valid_user_group_name(resolved_id)) {
1524                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_id);
1525                         return -EINVAL;
1526                 }
1527
1528                 if (description || home || shell) {
1529                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1530                                   fname, line, action[0],
1531                                   description ? "GECOS" : home ? "home directory" : "login shell");
1532                         return -EINVAL;
1533                 }
1534
1535                 r = ordered_hashmap_ensure_allocated(&members, &string_hash_ops);
1536                 if (r < 0)
1537                         return log_oom();
1538
1539                 l = ordered_hashmap_get(members, resolved_id);
1540                 if (l) {
1541                         /* A list for this group name already exists, let's append to it */
1542                         r = strv_push(&l, resolved_name);
1543                         if (r < 0)
1544                                 return log_oom();
1545
1546                         resolved_name = NULL;
1547
1548                         assert_se(ordered_hashmap_update(members, resolved_id, l) >= 0);
1549                 } else {
1550                         /* No list for this group name exists yet, create one */
1551
1552                         l = new0(char *, 2);
1553                         if (!l)
1554                                 return -ENOMEM;
1555
1556                         l[0] = resolved_name;
1557                         l[1] = NULL;
1558
1559                         r = ordered_hashmap_put(members, resolved_id, l);
1560                         if (r < 0) {
1561                                 free(l);
1562                                 return log_oom();
1563                         }
1564
1565                         resolved_id = resolved_name = NULL;
1566                 }
1567
1568                 return 0;
1569         }
1570
1571         case ADD_USER:
1572                 if (!name) {
1573                         log_error("[%s:%u] Lines of type 'u' require a user name in the second field.", fname, line);
1574                         return -EINVAL;
1575                 }
1576
1577                 r = ordered_hashmap_ensure_allocated(&users, &string_hash_ops);
1578                 if (r < 0)
1579                         return log_oom();
1580
1581                 i = new0(Item, 1);
1582                 if (!i)
1583                         return log_oom();
1584
1585                 if (resolved_id) {
1586                         if (path_is_absolute(resolved_id)) {
1587                                 i->uid_path = TAKE_PTR(resolved_id);
1588
1589                                 path_kill_slashes(i->uid_path);
1590                         } else {
1591                                 _cleanup_free_ char *uid = NULL, *gid = NULL;
1592                                 if (split_pair(resolved_id, ":", &uid, &gid) == 0) {
1593                                         r = parse_gid(gid, &i->gid);
1594                                         if (r < 0)
1595                                                 return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1596                                         i->gid_set = true;
1597                                         i->id_set_strict = true;
1598                                         free_and_replace(resolved_id, uid);
1599                                 }
1600                                 if (!streq(resolved_id, "-")) {
1601                                         r = parse_uid(resolved_id, &i->uid);
1602                                         if (r < 0)
1603                                                 return log_error_errno(r, "Failed to parse UID: '%s': %m", id);
1604                                         i->uid_set = true;
1605                                 }
1606                         }
1607                 }
1608
1609                 i->description = TAKE_PTR(description);
1610                 i->home = TAKE_PTR(home);
1611                 i->shell = TAKE_PTR(resolved_shell);
1612
1613                 h = users;
1614                 break;
1615
1616         case ADD_GROUP:
1617                 if (!name) {
1618                         log_error("[%s:%u] Lines of type 'g' require a user name in the second field.", fname, line);
1619                         return -EINVAL;
1620                 }
1621
1622                 if (description || home || shell) {
1623                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1624                                   fname, line, action[0],
1625                                   description ? "GECOS" : home ? "home directory" : "login shell");
1626                         return -EINVAL;
1627                 }
1628
1629                 r = ordered_hashmap_ensure_allocated(&groups, &string_hash_ops);
1630                 if (r < 0)
1631                         return log_oom();
1632
1633                 i = new0(Item, 1);
1634                 if (!i)
1635                         return log_oom();
1636
1637                 if (resolved_id) {
1638                         if (path_is_absolute(resolved_id)) {
1639                                 i->gid_path = TAKE_PTR(resolved_id);
1640
1641                                 path_kill_slashes(i->gid_path);
1642                         } else {
1643                                 r = parse_gid(resolved_id, &i->gid);
1644                                 if (r < 0)
1645                                         return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1646
1647                                 i->gid_set = true;
1648                         }
1649                 }
1650
1651                 h = groups;
1652                 break;
1653
1654         default:
1655                 return -EBADMSG;
1656         }
1657
1658         i->type = action[0];
1659         i->name = TAKE_PTR(resolved_name);
1660
1661         existing = ordered_hashmap_get(h, i->name);
1662         if (existing) {
1663
1664                 /* Two identical items are fine */
1665                 if (!item_equal(existing, i))
1666                         log_warning("Two or more conflicting lines for %s configured, ignoring.", i->name);
1667
1668                 return 0;
1669         }
1670
1671         r = ordered_hashmap_put(h, i->name, i);
1672         if (r < 0)
1673                 return log_oom();
1674
1675         i = NULL;
1676         return 0;
1677 }
1678
1679 static int read_config_file(const char *fn, bool ignore_enoent) {
1680         _cleanup_fclose_ FILE *rf = NULL;
1681         FILE *f = NULL;
1682         char line[LINE_MAX];
1683         unsigned v = 0;
1684         int r = 0;
1685
1686         assert(fn);
1687
1688         if (streq(fn, "-"))
1689                 f = stdin;
1690         else {
1691                 r = search_and_fopen_nulstr(fn, "re", arg_root, conf_file_dirs, &rf);
1692                 if (r < 0) {
1693                         if (ignore_enoent && r == -ENOENT)
1694                                 return 0;
1695
1696                         return log_error_errno(r, "Failed to open '%s', ignoring: %m", fn);
1697                 }
1698
1699                 f = rf;
1700         }
1701
1702         FOREACH_LINE(line, f, break) {
1703                 char *l;
1704                 int k;
1705
1706                 v++;
1707
1708                 l = strstrip(line);
1709                 if (IN_SET(*l, 0, '#'))
1710                         continue;
1711
1712                 k = parse_line(fn, v, l);
1713                 if (k < 0 && r == 0)
1714                         r = k;
1715         }
1716
1717         if (ferror(f)) {
1718                 log_error_errno(errno, "Failed to read from file %s: %m", fn);
1719                 if (r == 0)
1720                         r = -EIO;
1721         }
1722
1723         return r;
1724 }
1725
1726 static void free_database(Hashmap *by_name, Hashmap *by_id) {
1727         char *name;
1728
1729         for (;;) {
1730                 name = hashmap_first(by_id);
1731                 if (!name)
1732                         break;
1733
1734                 hashmap_remove(by_name, name);
1735
1736                 hashmap_steal_first_key(by_id);
1737                 free(name);
1738         }
1739
1740         while ((name = hashmap_steal_first_key(by_name)))
1741                 free(name);
1742
1743         hashmap_free(by_name);
1744         hashmap_free(by_id);
1745 }
1746
1747 static void help(void) {
1748         printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
1749                "Creates system user accounts.\n\n"
1750                "  -h --help                 Show this help\n"
1751                "     --version              Show package version\n"
1752                "     --root=PATH            Operate on an alternate filesystem root\n"
1753                "     --replace=PATH         Treat arguments as replacement for PATH\n"
1754                "     --inline               Treat arguments as configuration lines\n"
1755                , program_invocation_short_name);
1756 }
1757
1758 static int parse_argv(int argc, char *argv[]) {
1759
1760         enum {
1761                 ARG_VERSION = 0x100,
1762                 ARG_ROOT,
1763                 ARG_REPLACE,
1764                 ARG_INLINE,
1765         };
1766
1767         static const struct option options[] = {
1768                 { "help",    no_argument,       NULL, 'h'         },
1769                 { "version", no_argument,       NULL, ARG_VERSION },
1770                 { "root",    required_argument, NULL, ARG_ROOT    },
1771                 { "replace", required_argument, NULL, ARG_REPLACE },
1772                 { "inline",  no_argument,       NULL, ARG_INLINE  },
1773                 {}
1774         };
1775
1776         int c, r;
1777
1778         assert(argc >= 0);
1779         assert(argv);
1780
1781         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
1782
1783                 switch (c) {
1784
1785                 case 'h':
1786                         help();
1787                         return 0;
1788
1789                 case ARG_VERSION:
1790                         return version();
1791
1792                 case ARG_ROOT:
1793                         r = parse_path_argument_and_warn(optarg, true, &arg_root);
1794                         if (r < 0)
1795                                 return r;
1796                         break;
1797
1798                 case ARG_REPLACE:
1799                         if (!path_is_absolute(optarg) ||
1800                             !endswith(optarg, ".conf")) {
1801                                 log_error("The argument to --replace= must an absolute path to a config file");
1802                                 return -EINVAL;
1803                         }
1804
1805                         arg_replace = optarg;
1806                         break;
1807
1808                 case ARG_INLINE:
1809                         arg_inline = true;
1810                         break;
1811
1812                 case '?':
1813                         return -EINVAL;
1814
1815                 default:
1816                         assert_not_reached("Unhandled option");
1817                 }
1818
1819         if (arg_replace && optind >= argc) {
1820                 log_error("When --replace= is given, some configuration items must be specified");
1821                 return -EINVAL;
1822         }
1823
1824         return 1;
1825 }
1826
1827 static int parse_arguments(char **args) {
1828         char **arg;
1829         unsigned pos = 1;
1830         int r;
1831
1832         STRV_FOREACH(arg, args) {
1833                 if (arg_inline)
1834                         /* Use (argument):n, where n==1 for the first positional arg */
1835                         r = parse_line("(argument)", pos, *arg);
1836                 else
1837                         r = read_config_file(*arg, false);
1838                 if (r < 0)
1839                         return r;
1840
1841                 pos++;
1842         }
1843
1844         return 0;
1845 }
1846
1847 static int read_config_files(const char* dirs, char **args) {
1848         _cleanup_strv_free_ char **files = NULL;
1849         _cleanup_free_ char *p = NULL;
1850         char **f;
1851         int r;
1852
1853         r = conf_files_list_nulstr(&files, ".conf", arg_root, 0, dirs);
1854         if (r < 0)
1855                 return log_error_errno(r, "Failed to enumerate sysusers.d files: %m");
1856
1857         if (arg_replace) {
1858                 r = conf_files_insert_nulstr(&files, arg_root, dirs, arg_replace);
1859                 if (r < 0)
1860                         return log_error_errno(r, "Failed to extend sysusers.d file list: %m");
1861
1862                 p = path_join(arg_root, arg_replace, NULL);
1863                 if (!p)
1864                         return log_oom();
1865         }
1866
1867         STRV_FOREACH(f, files)
1868                 if (p && path_equal(*f, p)) {
1869                         log_debug("Parsing arguments at position \"%s\"…", *f);
1870
1871                         r = parse_arguments(args);
1872                         if (r < 0)
1873                                 return r;
1874                 } else {
1875                         log_debug("Reading config file \"%s\"…", *f);
1876
1877                         /* Just warn, ignore result otherwise */
1878                         (void) read_config_file(*f, true);
1879                 }
1880
1881         return 0;
1882 }
1883
1884 int main(int argc, char *argv[]) {
1885
1886         _cleanup_close_ int lock = -1;
1887         Iterator iterator;
1888         int r;
1889         Item *i;
1890         char *n;
1891
1892         r = parse_argv(argc, argv);
1893         if (r <= 0)
1894                 goto finish;
1895
1896         log_set_target(LOG_TARGET_AUTO);
1897         log_parse_environment();
1898         log_open();
1899
1900         umask(0022);
1901
1902         r = mac_selinux_init();
1903         if (r < 0) {
1904                 log_error_errno(r, "SELinux setup failed: %m");
1905                 goto finish;
1906         }
1907
1908         /* If command line arguments are specified along with --replace, read all
1909          * configuration files and insert the positional arguments at the specified
1910          * place. Otherwise, if command line arguments are specified, execute just
1911          * them, and finally, without --replace= or any positional arguments, just
1912          * read configuration and execute it.
1913          */
1914         if (arg_replace || optind >= argc)
1915                 r = read_config_files(conf_file_dirs, argv + optind);
1916         else
1917                 r = parse_arguments(argv + optind);
1918         if (r < 0)
1919                 goto finish;
1920
1921         /* Let's tell nss-systemd not to synthesize the "root" and "nobody" entries for it, so that our detection
1922          * whether the names or UID/GID area already used otherwise doesn't get confused. After all, even though
1923          * nss-systemd synthesizes these users/groups, they should still appear in /etc/passwd and /etc/group, as the
1924          * synthesizing logic is merely supposed to be fallback for cases where we run with a completely unpopulated
1925          * /etc. */
1926         if (setenv("SYSTEMD_NSS_BYPASS_SYNTHETIC", "1", 1) < 0) {
1927                 r = log_error_errno(errno, "Failed to set SYSTEMD_NSS_BYPASS_SYNTHETIC environment variable: %m");
1928                 goto finish;
1929         }
1930
1931         if (!uid_range) {
1932                 /* Default to default range of 1..SYSTEM_UID_MAX */
1933                 r = uid_range_add(&uid_range, &n_uid_range, 1, SYSTEM_UID_MAX);
1934                 if (r < 0) {
1935                         log_oom();
1936                         goto finish;
1937                 }
1938         }
1939
1940         r = add_implicit();
1941         if (r < 0)
1942                 goto finish;
1943
1944         lock = take_etc_passwd_lock(arg_root);
1945         if (lock < 0) {
1946                 log_error_errno(lock, "Failed to take /etc/passwd lock: %m");
1947                 goto finish;
1948         }
1949
1950         r = load_user_database();
1951         if (r < 0) {
1952                 log_error_errno(r, "Failed to load user database: %m");
1953                 goto finish;
1954         }
1955
1956         r = load_group_database();
1957         if (r < 0) {
1958                 log_error_errno(r, "Failed to read group database: %m");
1959                 goto finish;
1960         }
1961
1962         ORDERED_HASHMAP_FOREACH(i, groups, iterator)
1963                 process_item(i);
1964
1965         ORDERED_HASHMAP_FOREACH(i, users, iterator)
1966                 process_item(i);
1967
1968         r = write_files();
1969         if (r < 0)
1970                 log_error_errno(r, "Failed to write files: %m");
1971
1972 finish:
1973         ordered_hashmap_free_with_destructor(groups, item_free);
1974         ordered_hashmap_free_with_destructor(users, item_free);
1975
1976         while ((n = ordered_hashmap_first_key(members))) {
1977                 strv_free(ordered_hashmap_steal_first(members));
1978                 free(n);
1979         }
1980         ordered_hashmap_free(members);
1981
1982         ordered_hashmap_free(todo_uids);
1983         ordered_hashmap_free(todo_gids);
1984
1985         free_database(database_user, database_uid);
1986         free_database(database_group, database_gid);
1987
1988         free(arg_root);
1989
1990         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
1991 }