src/sysusers/sysusers.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 /***
   3   Copyright 2014 Lennart Poettering
   4 ***/
   5
   6 #include <getopt.h>
   7 #include <utmp.h>
   8
   9 #include "alloc-util.h"
  10 #include "conf-files.h"
  11 #include "copy.h"
  12 #include "def.h"
  13 #include "fd-util.h"
  14 #include "fileio-label.h"
  15 #include "format-util.h"
  16 #include "fs-util.h"
  17 #include "hashmap.h"
  18 #include "pager.h"
  19 #include "path-util.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 "terminal-util.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 bool arg_no_pager = false;
  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_uid = NULL, *database_user = NULL;
  75 static Hashmap *database_gid = NULL, *database_group = NULL;
  76
  77 static uid_t search_uid = UID_INVALID;
  78 static UidRange *uid_range = NULL;
  79 static unsigned n_uid_range = 0;
  80
  81 static int load_user_database(void) {
  82         _cleanup_fclose_ FILE *f = NULL;
  83         const char *passwd_path;
  84         struct passwd *pw;
  85         int r;
  86
  87         passwd_path = prefix_roota(arg_root, "/etc/passwd");
  88         f = fopen(passwd_path, "re");
  89         if (!f)
  90                 return errno == ENOENT ? 0 : -errno;
  91
  92         r = hashmap_ensure_allocated(&database_user, &string_hash_ops);
  93         if (r < 0)
  94                 return r;
  95
  96         r = hashmap_ensure_allocated(&database_uid, NULL);
  97         if (r < 0)
  98                 return r;
  99
 100         while ((r = fgetpwent_sane(f, &pw)) > 0) {
 101                 char *n;
 102                 int k, q;
 103
 104                 n = strdup(pw->pw_name);
 105                 if (!n)
 106                         return -ENOMEM;
 107
 108                 k = hashmap_put(database_user, n, UID_TO_PTR(pw->pw_uid));
 109                 if (k < 0 && k != -EEXIST) {
 110                         free(n);
 111                         return k;
 112                 }
 113
 114                 q = hashmap_put(database_uid, UID_TO_PTR(pw->pw_uid), n);
 115                 if (q < 0 && q != -EEXIST) {
 116                         if (k <= 0)
 117                                 free(n);
 118                         return q;
 119                 }
 120
 121                 if (k <= 0 && q <= 0)
 122                         free(n);
 123         }
 124         return r;
 125 }
 126
 127 static int load_group_database(void) {
 128         _cleanup_fclose_ FILE *f = NULL;
 129         const char *group_path;
 130         struct group *gr;
 131         int r;
 132
 133         group_path = prefix_roota(arg_root, "/etc/group");
 134         f = fopen(group_path, "re");
 135         if (!f)
 136                 return errno == ENOENT ? 0 : -errno;
 137
 138         r = hashmap_ensure_allocated(&database_group, &string_hash_ops);
 139         if (r < 0)
 140                 return r;
 141
 142         r = hashmap_ensure_allocated(&database_gid, NULL);
 143         if (r < 0)
 144                 return r;
 145
 146         errno = 0;
 147         while ((gr = fgetgrent(f))) {
 148                 char *n;
 149                 int k, q;
 150
 151                 n = strdup(gr->gr_name);
 152                 if (!n)
 153                         return -ENOMEM;
 154
 155                 k = hashmap_put(database_group, n, GID_TO_PTR(gr->gr_gid));
 156                 if (k < 0 && k != -EEXIST) {
 157                         free(n);
 158                         return k;
 159                 }
 160
 161                 q = hashmap_put(database_gid, GID_TO_PTR(gr->gr_gid), n);
 162                 if (q < 0 && q != -EEXIST) {
 163                         if (k <= 0)
 164                                 free(n);
 165                         return q;
 166                 }
 167
 168                 if (k <= 0 && q <= 0)
 169                         free(n);
 170
 171                 errno = 0;
 172         }
 173         if (!IN_SET(errno, 0, ENOENT))
 174                 return -errno;
 175
 176         return 0;
 177 }
 178
 179 static int make_backup(const char *target, const char *x) {
 180         _cleanup_close_ int src = -1;
 181         _cleanup_fclose_ FILE *dst = NULL;
 182         _cleanup_free_ char *temp = NULL;
 183         char *backup;
 184         struct timespec ts[2];
 185         struct stat st;
 186         int r;
 187
 188         src = open(x, O_RDONLY|O_CLOEXEC|O_NOCTTY);
 189         if (src < 0) {
 190                 if (errno == ENOENT) /* No backup necessary... */
 191                         return 0;
 192
 193                 return -errno;
 194         }
 195
 196         if (fstat(src, &st) < 0)
 197                 return -errno;
 198
 199         r = fopen_temporary_label(target, x, &dst, &temp);
 200         if (r < 0)
 201                 return r;
 202
 203         r = copy_bytes(src, fileno(dst), (uint64_t) -1, COPY_REFLINK);
 204         if (r < 0)
 205                 goto fail;
 206
 207         /* Don't fail on chmod() or chown(). If it stays owned by us
 208          * and/or unreadable by others, then it isn't too bad... */
 209
 210         backup = strjoina(x, "-");
 211
 212         /* Copy over the access mask */
 213         if (fchmod(fileno(dst), st.st_mode & 07777) < 0)
 214                 log_warning_errno(errno, "Failed to change mode on %s: %m", backup);
 215
 216         if (fchown(fileno(dst), st.st_uid, st.st_gid)< 0)
 217                 log_warning_errno(errno, "Failed to change ownership of %s: %m", backup);
 218
 219         ts[0] = st.st_atim;
 220         ts[1] = st.st_mtim;
 221         if (futimens(fileno(dst), ts) < 0)
 222                 log_warning_errno(errno, "Failed to fix access and modification time of %s: %m", backup);
 223
 224         r = fflush_sync_and_check(dst);
 225         if (r < 0)
 226                 goto fail;
 227
 228         if (rename(temp, backup) < 0) {
 229                 r = -errno;
 230                 goto fail;
 231         }
 232
 233         return 0;
 234
 235 fail:
 236         unlink(temp);
 237         return r;
 238 }
 239
 240 static int putgrent_with_members(const struct group *gr, FILE *group) {
 241         char **a;
 242
 243         assert(gr);
 244         assert(group);
 245
 246         a = ordered_hashmap_get(members, gr->gr_name);
 247         if (a) {
 248                 _cleanup_strv_free_ char **l = NULL;
 249                 bool added = false;
 250                 char **i;
 251
 252                 l = strv_copy(gr->gr_mem);
 253                 if (!l)
 254                         return -ENOMEM;
 255
 256                 STRV_FOREACH(i, a) {
 257                         if (strv_find(l, *i))
 258                                 continue;
 259
 260                         if (strv_extend(&l, *i) < 0)
 261                                 return -ENOMEM;
 262
 263                         added = true;
 264                 }
 265
 266                 if (added) {
 267                         struct group t;
 268                         int r;
 269
 270                         strv_uniq(l);
 271                         strv_sort(l);
 272
 273                         t = *gr;
 274                         t.gr_mem = l;
 275
 276                         r = putgrent_sane(&t, group);
 277                         return r < 0 ? r : 1;
 278                 }
 279         }
 280
 281         return putgrent_sane(gr, group);
 282 }
 283
 284 #if ENABLE_GSHADOW
 285 static int putsgent_with_members(const struct sgrp *sg, FILE *gshadow) {
 286         char **a;
 287
 288         assert(sg);
 289         assert(gshadow);
 290
 291         a = ordered_hashmap_get(members, sg->sg_namp);
 292         if (a) {
 293                 _cleanup_strv_free_ char **l = NULL;
 294                 bool added = false;
 295                 char **i;
 296
 297                 l = strv_copy(sg->sg_mem);
 298                 if (!l)
 299                         return -ENOMEM;
 300
 301                 STRV_FOREACH(i, a) {
 302                         if (strv_find(l, *i))
 303                                 continue;
 304
 305                         if (strv_extend(&l, *i) < 0)
 306                                 return -ENOMEM;
 307
 308                         added = true;
 309                 }
 310
 311                 if (added) {
 312                         struct sgrp t;
 313                         int r;
 314
 315                         strv_uniq(l);
 316                         strv_sort(l);
 317
 318                         t = *sg;
 319                         t.sg_mem = l;
 320
 321                         r = putsgent_sane(&t, gshadow);
 322                         return r < 0 ? r : 1;
 323                 }
 324         }
 325
 326         return putsgent_sane(sg, gshadow);
 327 }
 328 #endif
 329
 330 static int sync_rights(FILE *from, FILE *to) {
 331         struct stat st;
 332
 333         if (fstat(fileno(from), &st) < 0)
 334                 return -errno;
 335
 336         if (fchmod(fileno(to), st.st_mode & 07777) < 0)
 337                 return -errno;
 338
 339         if (fchown(fileno(to), st.st_uid, st.st_gid) < 0)
 340                 return -errno;
 341
 342         return 0;
 343 }
 344
 345 static int rename_and_apply_smack(const char *temp_path, const char *dest_path) {
 346         int r = 0;
 347         if (rename(temp_path, dest_path) < 0)
 348                 return -errno;
 349
 350 #ifdef SMACK_RUN_LABEL
 351         r = mac_smack_apply(dest_path, SMACK_ATTR_ACCESS, SMACK_FLOOR_LABEL);
 352         if (r < 0)
 353                 return r;
 354 #endif
 355         return r;
 356 }
 357
 358 static const char* default_shell(uid_t uid) {
 359         return uid == 0 ? "/bin/sh" : "/sbin/nologin";
 360 }
 361
 362 static int write_temporary_passwd(const char *passwd_path, FILE **tmpfile, char **tmpfile_path) {
 363         _cleanup_fclose_ FILE *original = NULL, *passwd = NULL;
 364         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL;
 365         struct passwd *pw = NULL;
 366         Iterator iterator;
 367         Item *i;
 368         int r;
 369
 370         if (ordered_hashmap_size(todo_uids) == 0)
 371                 return 0;
 372
 373         r = fopen_temporary_label("/etc/passwd", passwd_path, &passwd, &passwd_tmp);
 374         if (r < 0)
 375                 return r;
 376
 377         original = fopen(passwd_path, "re");
 378         if (original) {
 379
 380                 r = sync_rights(original, passwd);
 381                 if (r < 0)
 382                         return r;
 383
 384                 while ((r = fgetpwent_sane(original, &pw)) > 0) {
 385
 386                         i = ordered_hashmap_get(users, pw->pw_name);
 387                         if (i && i->todo_user) {
 388                                 log_error("%s: User \"%s\" already exists.", passwd_path, pw->pw_name);
 389                                 return -EEXIST;
 390                         }
 391
 392                         if (ordered_hashmap_contains(todo_uids, UID_TO_PTR(pw->pw_uid))) {
 393                                 log_error("%s: Detected collision for UID " UID_FMT ".", passwd_path, pw->pw_uid);
 394                                 return -EEXIST;
 395                         }
 396
 397                         /* Make sure we keep the NIS entries (if any) at the end. */
 398                         if (IN_SET(pw->pw_name[0], '+', '-'))
 399                                 break;
 400
 401                         r = putpwent_sane(pw, passwd);
 402                         if (r < 0)
 403                                 return r;
 404                 }
 405                 if (r < 0)
 406                         return r;
 407
 408         } else {
 409                 if (errno != ENOENT)
 410                         return -errno;
 411                 if (fchmod(fileno(passwd), 0644) < 0)
 412                         return -errno;
 413         }
 414
 415         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 416                 struct passwd n = {
 417                         .pw_name = i->name,
 418                         .pw_uid = i->uid,
 419                         .pw_gid = i->gid,
 420                         .pw_gecos = i->description,
 421
 422                         /* "x" means the password is stored in the shadow file */
 423                         .pw_passwd = (char*) "x",
 424
 425                         /* We default to the root directory as home */
 426                         .pw_dir = i->home ? i->home : (char*) "/",
 427
 428                         /* Initialize the shell to nologin, with one exception:
 429                          * for root we patch in something special */
 430                         .pw_shell = i->shell ?: (char*) default_shell(i->uid),
 431                 };
 432
 433                 r = putpwent_sane(&n, passwd);
 434                 if (r < 0)
 435                         return r;
 436         }
 437
 438         /* Append the remaining NIS entries if any */
 439         while (pw) {
 440                 r = putpwent_sane(pw, passwd);
 441                 if (r < 0)
 442                         return r;
 443
 444                 r = fgetpwent_sane(original, &pw);
 445                 if (r < 0)
 446                         return r;
 447                 if (r == 0)
 448                         break;
 449         }
 450
 451         r = fflush_and_check(passwd);
 452         if (r < 0)
 453                 return r;
 454
 455         *tmpfile = TAKE_PTR(passwd);
 456         *tmpfile_path = TAKE_PTR(passwd_tmp);
 457
 458         return 0;
 459 }
 460
 461 static int write_temporary_shadow(const char *shadow_path, FILE **tmpfile, char **tmpfile_path) {
 462         _cleanup_fclose_ FILE *original = NULL, *shadow = NULL;
 463         _cleanup_(unlink_and_freep) char *shadow_tmp = NULL;
 464         struct spwd *sp = NULL;
 465         Iterator iterator;
 466         long lstchg;
 467         Item *i;
 468         int r;
 469
 470         if (ordered_hashmap_size(todo_uids) == 0)
 471                 return 0;
 472
 473         r = fopen_temporary_label("/etc/shadow", shadow_path, &shadow, &shadow_tmp);
 474         if (r < 0)
 475                 return r;
 476
 477         lstchg = (long) (now(CLOCK_REALTIME) / USEC_PER_DAY);
 478
 479         original = fopen(shadow_path, "re");
 480         if (original) {
 481
 482                 r = sync_rights(original, shadow);
 483                 if (r < 0)
 484                         return r;
 485
 486                 while ((r = fgetspent_sane(original, &sp)) > 0) {
 487
 488                         i = ordered_hashmap_get(users, sp->sp_namp);
 489                         if (i && i->todo_user) {
 490                                 /* we will update the existing entry */
 491                                 sp->sp_lstchg = lstchg;
 492
 493                                 /* only the /etc/shadow stage is left, so we can
 494                                  * safely remove the item from the todo set */
 495                                 i->todo_user = false;
 496                                 ordered_hashmap_remove(todo_uids, UID_TO_PTR(i->uid));
 497                         }
 498
 499                         /* Make sure we keep the NIS entries (if any) at the end. */
 500                         if (IN_SET(sp->sp_namp[0], '+', '-'))
 501                                 break;
 502
 503                         r = putspent_sane(sp, shadow);
 504                         if (r < 0)
 505                                 return r;
 506                 }
 507                 if (r < 0)
 508                         return r;
 509
 510         } else {
 511                 if (errno != ENOENT)
 512                         return -errno;
 513                 if (fchmod(fileno(shadow), 0000) < 0)
 514                         return -errno;
 515         }
 516
 517         ORDERED_HASHMAP_FOREACH(i, todo_uids, iterator) {
 518                 struct spwd n = {
 519                         .sp_namp = i->name,
 520                         .sp_pwdp = (char*) "!!",
 521                         .sp_lstchg = lstchg,
 522                         .sp_min = -1,
 523                         .sp_max = -1,
 524                         .sp_warn = -1,
 525                         .sp_inact = -1,
 526                         .sp_expire = -1,
 527                         .sp_flag = (unsigned long) -1, /* this appears to be what everybody does ... */
 528                 };
 529
 530                 r = putspent_sane(&n, shadow);
 531                 if (r < 0)
 532                         return r;
 533         }
 534
 535         /* Append the remaining NIS entries if any */
 536         while (sp) {
 537                 r = putspent_sane(sp, shadow);
 538                 if (r < 0)
 539                         return r;
 540
 541                 r = fgetspent_sane(original, &sp);
 542                 if (r < 0)
 543                         return r;
 544                 if (r == 0)
 545                         break;
 546         }
 547         if (!IN_SET(errno, 0, ENOENT))
 548                 return -errno;
 549
 550         r = fflush_sync_and_check(shadow);
 551         if (r < 0)
 552                 return r;
 553
 554         *tmpfile = TAKE_PTR(shadow);
 555         *tmpfile_path = TAKE_PTR(shadow_tmp);
 556
 557         return 0;
 558 }
 559
 560 static int write_temporary_group(const char *group_path, FILE **tmpfile, char **tmpfile_path) {
 561         _cleanup_fclose_ FILE *original = NULL, *group = NULL;
 562         _cleanup_(unlink_and_freep) char *group_tmp = NULL;
 563         bool group_changed = false;
 564         struct group *gr = NULL;
 565         Iterator iterator;
 566         Item *i;
 567         int r;
 568
 569         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 570                 return 0;
 571
 572         r = fopen_temporary_label("/etc/group", group_path, &group, &group_tmp);
 573         if (r < 0)
 574                 return r;
 575
 576         original = fopen(group_path, "re");
 577         if (original) {
 578
 579                 r = sync_rights(original, group);
 580                 if (r < 0)
 581                         return r;
 582
 583                 while ((r = fgetgrent_sane(original, &gr)) > 0) {
 584                         /* Safety checks against name and GID collisions. Normally,
 585                          * this should be unnecessary, but given that we look at the
 586                          * entries anyway here, let's make an extra verification
 587                          * step that we don't generate duplicate entries. */
 588
 589                         i = ordered_hashmap_get(groups, gr->gr_name);
 590                         if (i && i->todo_group) {
 591                                 log_error("%s: Group \"%s\" already exists.", group_path, gr->gr_name);
 592                                 return -EEXIST;
 593                         }
 594
 595                         if (ordered_hashmap_contains(todo_gids, GID_TO_PTR(gr->gr_gid))) {
 596                                 log_error("%s: Detected collision for GID " GID_FMT ".", group_path, gr->gr_gid);
 597                                 return  -EEXIST;
 598                         }
 599
 600                         /* Make sure we keep the NIS entries (if any) at the end. */
 601                         if (IN_SET(gr->gr_name[0], '+', '-'))
 602                                 break;
 603
 604                         r = putgrent_with_members(gr, group);
 605                         if (r < 0)
 606                                 return r;
 607                         if (r > 0)
 608                                 group_changed = true;
 609                 }
 610                 if (r < 0)
 611                         return r;
 612
 613         } else {
 614                 if (errno != ENOENT)
 615                         return -errno;
 616                 if (fchmod(fileno(group), 0644) < 0)
 617                         return -errno;
 618         }
 619
 620         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 621                 struct group n = {
 622                         .gr_name = i->name,
 623                         .gr_gid = i->gid,
 624                         .gr_passwd = (char*) "x",
 625                 };
 626
 627                 r = putgrent_with_members(&n, group);
 628                 if (r < 0)
 629                         return r;
 630
 631                 group_changed = true;
 632         }
 633
 634         /* Append the remaining NIS entries if any */
 635         while (gr) {
 636                 r = putgrent_sane(gr, group);
 637                 if (r < 0)
 638                         return r;
 639
 640                 r = fgetgrent_sane(original, &gr);
 641                 if (r < 0)
 642                         return r;
 643                 if (r == 0)
 644                         break;
 645         }
 646
 647         r = fflush_sync_and_check(group);
 648         if (r < 0)
 649                 return r;
 650
 651         if (group_changed) {
 652                 *tmpfile = TAKE_PTR(group);
 653                 *tmpfile_path = TAKE_PTR(group_tmp);
 654         }
 655         return 0;
 656 }
 657
 658 static int write_temporary_gshadow(const char * gshadow_path, FILE **tmpfile, char **tmpfile_path) {
 659 #if ENABLE_GSHADOW
 660         _cleanup_fclose_ FILE *original = NULL, *gshadow = NULL;
 661         _cleanup_(unlink_and_freep) char *gshadow_tmp = NULL;
 662         bool group_changed = false;
 663         Iterator iterator;
 664         Item *i;
 665         int r;
 666
 667         if (ordered_hashmap_size(todo_gids) == 0 && ordered_hashmap_size(members) == 0)
 668                 return 0;
 669
 670         r = fopen_temporary_label("/etc/gshadow", gshadow_path, &gshadow, &gshadow_tmp);
 671         if (r < 0)
 672                 return r;
 673
 674         original = fopen(gshadow_path, "re");
 675         if (original) {
 676                 struct sgrp *sg;
 677
 678                 r = sync_rights(original, gshadow);
 679                 if (r < 0)
 680                         return r;
 681
 682                 while ((r = fgetsgent_sane(original, &sg)) > 0) {
 683
 684                         i = ordered_hashmap_get(groups, sg->sg_namp);
 685                         if (i && i->todo_group) {
 686                                 log_error("%s: Group \"%s\" already exists.", gshadow_path, sg->sg_namp);
 687                                 return -EEXIST;
 688                         }
 689
 690                         r = putsgent_with_members(sg, gshadow);
 691                         if (r < 0)
 692                                 return r;
 693                         if (r > 0)
 694                                 group_changed = true;
 695                 }
 696                 if (r < 0)
 697                         return r;
 698
 699         } else {
 700                 if (errno != ENOENT)
 701                         return -errno;
 702                 if (fchmod(fileno(gshadow), 0000) < 0)
 703                         return -errno;
 704         }
 705
 706         ORDERED_HASHMAP_FOREACH(i, todo_gids, iterator) {
 707                 struct sgrp n = {
 708                         .sg_namp = i->name,
 709                         .sg_passwd = (char*) "!!",
 710                 };
 711
 712                 r = putsgent_with_members(&n, gshadow);
 713                 if (r < 0)
 714                         return r;
 715
 716                 group_changed = true;
 717         }
 718
 719         r = fflush_sync_and_check(gshadow);
 720         if (r < 0)
 721                 return r;
 722
 723         if (group_changed) {
 724                 *tmpfile = TAKE_PTR(gshadow);
 725                 *tmpfile_path = TAKE_PTR(gshadow_tmp);
 726         }
 727         return 0;
 728 #else
 729         return 0;
 730 #endif
 731 }
 732
 733 static int write_files(void) {
 734         _cleanup_fclose_ FILE *passwd = NULL, *group = NULL, *shadow = NULL, *gshadow = NULL;
 735         _cleanup_(unlink_and_freep) char *passwd_tmp = NULL, *group_tmp = NULL, *shadow_tmp = NULL, *gshadow_tmp = NULL;
 736         const char *passwd_path = NULL, *group_path = NULL, *shadow_path = NULL, *gshadow_path = NULL;
 737         int r;
 738
 739         passwd_path = prefix_roota(arg_root, "/etc/passwd");
 740         shadow_path = prefix_roota(arg_root, "/etc/shadow");
 741         group_path = prefix_roota(arg_root, "/etc/group");
 742         gshadow_path = prefix_roota(arg_root, "/etc/gshadow");
 743
 744         r = write_temporary_group(group_path, &group, &group_tmp);
 745         if (r < 0)
 746                 return r;
 747
 748         r = write_temporary_gshadow(gshadow_path, &gshadow, &gshadow_tmp);
 749         if (r < 0)
 750                 return r;
 751
 752         r = write_temporary_passwd(passwd_path, &passwd, &passwd_tmp);
 753         if (r < 0)
 754                 return r;
 755
 756         r = write_temporary_shadow(shadow_path, &shadow, &shadow_tmp);
 757         if (r < 0)
 758                 return r;
 759
 760         /* Make a backup of the old files */
 761         if (group) {
 762                 r = make_backup("/etc/group", group_path);
 763                 if (r < 0)
 764                         return r;
 765         }
 766         if (gshadow) {
 767                 r = make_backup("/etc/gshadow", gshadow_path);
 768                 if (r < 0)
 769                         return r;
 770         }
 771
 772         if (passwd) {
 773                 r = make_backup("/etc/passwd", passwd_path);
 774                 if (r < 0)
 775                         return r;
 776         }
 777         if (shadow) {
 778                 r = make_backup("/etc/shadow", shadow_path);
 779                 if (r < 0)
 780                         return r;
 781         }
 782
 783         /* And make the new files count */
 784         if (group) {
 785                 r = rename_and_apply_smack(group_tmp, group_path);
 786                 if (r < 0)
 787                         return r;
 788
 789                 group_tmp = mfree(group_tmp);
 790         }
 791         if (gshadow) {
 792                 r = rename_and_apply_smack(gshadow_tmp, gshadow_path);
 793                 if (r < 0)
 794                         return r;
 795
 796                 gshadow_tmp = mfree(gshadow_tmp);
 797         }
 798
 799         if (passwd) {
 800                 r = rename_and_apply_smack(passwd_tmp, passwd_path);
 801                 if (r < 0)
 802                         return r;
 803
 804                 passwd_tmp = mfree(passwd_tmp);
 805         }
 806         if (shadow) {
 807                 r = rename_and_apply_smack(shadow_tmp, shadow_path);
 808                 if (r < 0)
 809                         return r;
 810
 811                 shadow_tmp = mfree(shadow_tmp);
 812         }
 813
 814         return 0;
 815 }
 816
 817 static int uid_is_ok(uid_t uid, const char *name, bool check_with_gid) {
 818         struct passwd *p;
 819         struct group *g;
 820         const char *n;
 821         Item *i;
 822
 823         /* Let's see if we already have assigned the UID a second time */
 824         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(uid)))
 825                 return 0;
 826
 827         /* Try to avoid using uids that are already used by a group
 828          * that doesn't have the same name as our new user. */
 829         if (check_with_gid) {
 830                 i = ordered_hashmap_get(todo_gids, GID_TO_PTR(uid));
 831                 if (i && !streq(i->name, name))
 832                         return 0;
 833         }
 834
 835         /* Let's check the files directly */
 836         if (hashmap_contains(database_uid, UID_TO_PTR(uid)))
 837                 return 0;
 838
 839         if (check_with_gid) {
 840                 n = hashmap_get(database_gid, GID_TO_PTR(uid));
 841                 if (n && !streq(n, name))
 842                         return 0;
 843         }
 844
 845         /* Let's also check via NSS, to avoid UID clashes over LDAP and such, just in case */
 846         if (!arg_root) {
 847                 errno = 0;
 848                 p = getpwuid(uid);
 849                 if (p)
 850                         return 0;
 851                 if (!IN_SET(errno, 0, ENOENT))
 852                         return -errno;
 853
 854                 if (check_with_gid) {
 855                         errno = 0;
 856                         g = getgrgid((gid_t) uid);
 857                         if (g) {
 858                                 if (!streq(g->gr_name, name))
 859                                         return 0;
 860                         } else if (!IN_SET(errno, 0, ENOENT))
 861                                 return -errno;
 862                 }
 863         }
 864
 865         return 1;
 866 }
 867
 868 static int root_stat(const char *p, struct stat *st) {
 869         const char *fix;
 870
 871         fix = prefix_roota(arg_root, p);
 872         if (stat(fix, st) < 0)
 873                 return -errno;
 874
 875         return 0;
 876 }
 877
 878 static int read_id_from_file(Item *i, uid_t *_uid, gid_t *_gid) {
 879         struct stat st;
 880         bool found_uid = false, found_gid = false;
 881         uid_t uid = 0;
 882         gid_t gid = 0;
 883
 884         assert(i);
 885
 886         /* First, try to get the gid directly */
 887         if (_gid && i->gid_path && root_stat(i->gid_path, &st) >= 0) {
 888                 gid = st.st_gid;
 889                 found_gid = true;
 890         }
 891
 892         /* Then, try to get the uid directly */
 893         if ((_uid || (_gid && !found_gid))
 894             && i->uid_path
 895             && root_stat(i->uid_path, &st) >= 0) {
 896
 897                 uid = st.st_uid;
 898                 found_uid = true;
 899
 900                 /* If we need the gid, but had no success yet, also derive it from the uid path */
 901                 if (_gid && !found_gid) {
 902                         gid = st.st_gid;
 903                         found_gid = true;
 904                 }
 905         }
 906
 907         /* If that didn't work yet, then let's reuse the gid as uid */
 908         if (_uid && !found_uid && i->gid_path) {
 909
 910                 if (found_gid) {
 911                         uid = (uid_t) gid;
 912                         found_uid = true;
 913                 } else if (root_stat(i->gid_path, &st) >= 0) {
 914                         uid = (uid_t) st.st_gid;
 915                         found_uid = true;
 916                 }
 917         }
 918
 919         if (_uid) {
 920                 if (!found_uid)
 921                         return 0;
 922
 923                 *_uid = uid;
 924         }
 925
 926         if (_gid) {
 927                 if (!found_gid)
 928                         return 0;
 929
 930                 *_gid = gid;
 931         }
 932
 933         return 1;
 934 }
 935
 936 static int add_user(Item *i) {
 937         void *z;
 938         int r;
 939
 940         assert(i);
 941
 942         /* Check the database directly */
 943         z = hashmap_get(database_user, i->name);
 944         if (z) {
 945                 log_debug("User %s already exists.", i->name);
 946                 i->uid = PTR_TO_UID(z);
 947                 i->uid_set = true;
 948                 return 0;
 949         }
 950
 951         if (!arg_root) {
 952                 struct passwd *p;
 953
 954                 /* Also check NSS */
 955                 errno = 0;
 956                 p = getpwnam(i->name);
 957                 if (p) {
 958                         log_debug("User %s already exists.", i->name);
 959                         i->uid = p->pw_uid;
 960                         i->uid_set = true;
 961
 962                         r = free_and_strdup(&i->description, p->pw_gecos);
 963                         if (r < 0)
 964                                 return log_oom();
 965
 966                         return 0;
 967                 }
 968                 if (!IN_SET(errno, 0, ENOENT))
 969                         return log_error_errno(errno, "Failed to check if user %s already exists: %m", i->name);
 970         }
 971
 972         /* Try to use the suggested numeric uid */
 973         if (i->uid_set) {
 974                 r = uid_is_ok(i->uid, i->name, !i->id_set_strict);
 975                 if (r < 0)
 976                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
 977                 if (r == 0) {
 978                         log_debug("Suggested user ID " UID_FMT " for %s already used.", i->uid, i->name);
 979                         i->uid_set = false;
 980                 }
 981         }
 982
 983         /* If that didn't work, try to read it from the specified path */
 984         if (!i->uid_set) {
 985                 uid_t c;
 986
 987                 if (read_id_from_file(i, &c, NULL) > 0) {
 988
 989                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
 990                                 log_debug("User ID " UID_FMT " of file not suitable for %s.", c, i->name);
 991                         else {
 992                                 r = uid_is_ok(c, i->name, true);
 993                                 if (r < 0)
 994                                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
 995                                 else if (r > 0) {
 996                                         i->uid = c;
 997                                         i->uid_set = true;
 998                                 } else
 999                                         log_debug("User ID " UID_FMT " of file for %s is already used.", c, i->name);
1000                         }
1001                 }
1002         }
1003
1004         /* Otherwise, try to reuse the group ID */
1005         if (!i->uid_set && i->gid_set) {
1006                 r = uid_is_ok((uid_t) i->gid, i->name, true);
1007                 if (r < 0)
1008                         return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1009                 if (r > 0) {
1010                         i->uid = (uid_t) i->gid;
1011                         i->uid_set = true;
1012                 }
1013         }
1014
1015         /* And if that didn't work either, let's try to find a free one */
1016         if (!i->uid_set) {
1017                 for (;;) {
1018                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1019                         if (r < 0) {
1020                                 log_error("No free user ID available for %s.", i->name);
1021                                 return r;
1022                         }
1023
1024                         r = uid_is_ok(search_uid, i->name, true);
1025                         if (r < 0)
1026                                 return log_error_errno(r, "Failed to verify uid " UID_FMT ": %m", i->uid);
1027                         else if (r > 0)
1028                                 break;
1029                 }
1030
1031                 i->uid_set = true;
1032                 i->uid = search_uid;
1033         }
1034
1035         r = ordered_hashmap_ensure_allocated(&todo_uids, NULL);
1036         if (r < 0)
1037                 return log_oom();
1038
1039         r = ordered_hashmap_put(todo_uids, UID_TO_PTR(i->uid), i);
1040         if (r < 0)
1041                 return log_oom();
1042
1043         i->todo_user = true;
1044         log_info("Creating user %s (%s) with uid " UID_FMT " and gid " GID_FMT ".", i->name, strna(i->description), i->uid, i->gid);
1045
1046         return 0;
1047 }
1048
1049 static int gid_is_ok(gid_t gid) {
1050         struct group *g;
1051         struct passwd *p;
1052
1053         if (ordered_hashmap_get(todo_gids, GID_TO_PTR(gid)))
1054                 return 0;
1055
1056         /* Avoid reusing gids that are already used by a different user */
1057         if (ordered_hashmap_get(todo_uids, UID_TO_PTR(gid)))
1058                 return 0;
1059
1060         if (hashmap_contains(database_gid, GID_TO_PTR(gid)))
1061                 return 0;
1062
1063         if (hashmap_contains(database_uid, UID_TO_PTR(gid)))
1064                 return 0;
1065
1066         if (!arg_root) {
1067                 errno = 0;
1068                 g = getgrgid(gid);
1069                 if (g)
1070                         return 0;
1071                 if (!IN_SET(errno, 0, ENOENT))
1072                         return -errno;
1073
1074                 errno = 0;
1075                 p = getpwuid((uid_t) gid);
1076                 if (p)
1077                         return 0;
1078                 if (!IN_SET(errno, 0, ENOENT))
1079                         return -errno;
1080         }
1081
1082         return 1;
1083 }
1084
1085 static int add_group(Item *i) {
1086         void *z;
1087         int r;
1088
1089         assert(i);
1090
1091         /* Check the database directly */
1092         z = hashmap_get(database_group, i->name);
1093         if (z) {
1094                 log_debug("Group %s already exists.", i->name);
1095                 i->gid = PTR_TO_GID(z);
1096                 i->gid_set = true;
1097                 return 0;
1098         }
1099
1100         /* Also check NSS */
1101         if (!arg_root) {
1102                 struct group *g;
1103
1104                 errno = 0;
1105                 g = getgrnam(i->name);
1106                 if (g) {
1107                         log_debug("Group %s already exists.", i->name);
1108                         i->gid = g->gr_gid;
1109                         i->gid_set = true;
1110                         return 0;
1111                 }
1112                 if (!IN_SET(errno, 0, ENOENT))
1113                         return log_error_errno(errno, "Failed to check if group %s already exists: %m", i->name);
1114         }
1115
1116         /* Try to use the suggested numeric gid */
1117         if (i->gid_set) {
1118                 r = gid_is_ok(i->gid);
1119                 if (r < 0)
1120                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1121                 if (i->id_set_strict) {
1122                         /* If we require the gid to already exist we can return here:
1123                          * r > 0: means the gid does not exist -> fail
1124                          * r == 0: means the gid exists -> nothing more to do.
1125                          */
1126                         if (r > 0) {
1127                                 log_error("Failed to create %s: please create GID %d", i->name, i->gid);
1128                                 return -EINVAL;
1129                         }
1130                         if (r == 0)
1131                                 return 0;
1132                 }
1133                 if (r == 0) {
1134                         log_debug("Suggested group ID " GID_FMT " for %s already used.", i->gid, i->name);
1135                         i->gid_set = false;
1136                 }
1137         }
1138
1139         /* Try to reuse the numeric uid, if there's one */
1140         if (!i->gid_set && i->uid_set) {
1141                 r = gid_is_ok((gid_t) i->uid);
1142                 if (r < 0)
1143                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1144                 if (r > 0) {
1145                         i->gid = (gid_t) i->uid;
1146                         i->gid_set = true;
1147                 }
1148         }
1149
1150         /* If that didn't work, try to read it from the specified path */
1151         if (!i->gid_set) {
1152                 gid_t c;
1153
1154                 if (read_id_from_file(i, NULL, &c) > 0) {
1155
1156                         if (c <= 0 || !uid_range_contains(uid_range, n_uid_range, c))
1157                                 log_debug("Group ID " GID_FMT " of file not suitable for %s.", c, i->name);
1158                         else {
1159                                 r = gid_is_ok(c);
1160                                 if (r < 0)
1161                                         return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1162                                 else if (r > 0) {
1163                                         i->gid = c;
1164                                         i->gid_set = true;
1165                                 } else
1166                                         log_debug("Group ID " GID_FMT " of file for %s already used.", c, i->name);
1167                         }
1168                 }
1169         }
1170
1171         /* And if that didn't work either, let's try to find a free one */
1172         if (!i->gid_set) {
1173                 for (;;) {
1174                         /* We look for new GIDs in the UID pool! */
1175                         r = uid_range_next_lower(uid_range, n_uid_range, &search_uid);
1176                         if (r < 0) {
1177                                 log_error("No free group ID available for %s.", i->name);
1178                                 return r;
1179                         }
1180
1181                         r = gid_is_ok(search_uid);
1182                         if (r < 0)
1183                                 return log_error_errno(r, "Failed to verify gid " GID_FMT ": %m", i->gid);
1184                         else if (r > 0)
1185                                 break;
1186                 }
1187
1188                 i->gid_set = true;
1189                 i->gid = search_uid;
1190         }
1191
1192         r = ordered_hashmap_ensure_allocated(&todo_gids, NULL);
1193         if (r < 0)
1194                 return log_oom();
1195
1196         r = ordered_hashmap_put(todo_gids, GID_TO_PTR(i->gid), i);
1197         if (r < 0)
1198                 return log_oom();
1199
1200         i->todo_group = true;
1201         log_info("Creating group %s with gid " GID_FMT ".", i->name, i->gid);
1202
1203         return 0;
1204 }
1205
1206 static int process_item(Item *i) {
1207         int r;
1208
1209         assert(i);
1210
1211         switch (i->type) {
1212
1213         case ADD_USER: {
1214                 Item *j;
1215
1216                 j = ordered_hashmap_get(groups, i->name);
1217                 if (j && j->todo_group) {
1218                         /* When the group with the same name is already in queue,
1219                          * use the information about the group and do not create
1220                          * duplicated group entry. */
1221                         i->gid_set = j->gid_set;
1222                         i->gid = j->gid;
1223                         i->id_set_strict = true;
1224                 } else {
1225                         r = add_group(i);
1226                         if (r < 0)
1227                                 return r;
1228                 }
1229
1230                 return add_user(i);
1231         }
1232
1233         case ADD_GROUP:
1234                 return add_group(i);
1235
1236         default:
1237                 assert_not_reached("Unknown item type");
1238         }
1239 }
1240
1241 static void item_free(Item *i) {
1242
1243         if (!i)
1244                 return;
1245
1246         free(i->name);
1247         free(i->uid_path);
1248         free(i->gid_path);
1249         free(i->description);
1250         free(i->home);
1251         free(i->shell);
1252         free(i);
1253 }
1254
1255 DEFINE_TRIVIAL_CLEANUP_FUNC(Item*, item_free);
1256
1257 static int add_implicit(void) {
1258         char *g, **l;
1259         Iterator iterator;
1260         int r;
1261
1262         /* Implicitly create additional users and groups, if they were listed in "m" lines */
1263         ORDERED_HASHMAP_FOREACH_KEY(l, g, members, iterator) {
1264                 char **m;
1265
1266                 STRV_FOREACH(m, l)
1267                         if (!ordered_hashmap_get(users, *m)) {
1268                                 _cleanup_(item_freep) Item *j = NULL;
1269
1270                                 r = ordered_hashmap_ensure_allocated(&users, &string_hash_ops);
1271                                 if (r < 0)
1272                                         return log_oom();
1273
1274                                 j = new0(Item, 1);
1275                                 if (!j)
1276                                         return log_oom();
1277
1278                                 j->type = ADD_USER;
1279                                 j->name = strdup(*m);
1280                                 if (!j->name)
1281                                         return log_oom();
1282
1283                                 r = ordered_hashmap_put(users, j->name, j);
1284                                 if (r < 0)
1285                                         return log_oom();
1286
1287                                 log_debug("Adding implicit user '%s' due to m line", j->name);
1288                                 j = NULL;
1289                         }
1290
1291                 if (!(ordered_hashmap_get(users, g) ||
1292                       ordered_hashmap_get(groups, g))) {
1293                         _cleanup_(item_freep) Item *j = NULL;
1294
1295                         r = ordered_hashmap_ensure_allocated(&groups, &string_hash_ops);
1296                         if (r < 0)
1297                                 return log_oom();
1298
1299                         j = new0(Item, 1);
1300                         if (!j)
1301                                 return log_oom();
1302
1303                         j->type = ADD_GROUP;
1304                         j->name = strdup(g);
1305                         if (!j->name)
1306                                 return log_oom();
1307
1308                         r = ordered_hashmap_put(groups, j->name, j);
1309                         if (r < 0)
1310                                 return log_oom();
1311
1312                         log_debug("Adding implicit group '%s' due to m line", j->name);
1313                         j = NULL;
1314                 }
1315         }
1316
1317         return 0;
1318 }
1319
1320 static bool item_equal(Item *a, Item *b) {
1321         assert(a);
1322         assert(b);
1323
1324         if (a->type != b->type)
1325                 return false;
1326
1327         if (!streq_ptr(a->name, b->name))
1328                 return false;
1329
1330         if (!streq_ptr(a->uid_path, b->uid_path))
1331                 return false;
1332
1333         if (!streq_ptr(a->gid_path, b->gid_path))
1334                 return false;
1335
1336         if (!streq_ptr(a->description, b->description))
1337                 return false;
1338
1339         if (a->uid_set != b->uid_set)
1340                 return false;
1341
1342         if (a->uid_set && a->uid != b->uid)
1343                 return false;
1344
1345         if (a->gid_set != b->gid_set)
1346                 return false;
1347
1348         if (a->gid_set && a->gid != b->gid)
1349                 return false;
1350
1351         if (!streq_ptr(a->home, b->home))
1352                 return false;
1353
1354         if (!streq_ptr(a->shell, b->shell))
1355                 return false;
1356
1357         return true;
1358 }
1359
1360 static int parse_line(const char *fname, unsigned line, const char *buffer) {
1361
1362         static const Specifier specifier_table[] = {
1363                 { 'm', specifier_machine_id,     NULL },
1364                 { 'b', specifier_boot_id,        NULL },
1365                 { 'H', specifier_host_name,      NULL },
1366                 { 'v', specifier_kernel_release, NULL },
1367                 { 'T', specifier_tmp_dir,        NULL },
1368                 { 'V', specifier_var_tmp_dir,    NULL },
1369                 {}
1370         };
1371
1372         _cleanup_free_ char *action = NULL,
1373                 *name = NULL, *resolved_name = NULL,
1374                 *id = NULL, *resolved_id = NULL,
1375                 *description = NULL, *resolved_description = NULL,
1376                 *home = NULL, *resolved_home = NULL,
1377                 *shell, *resolved_shell = NULL;
1378         _cleanup_(item_freep) Item *i = NULL;
1379         Item *existing;
1380         OrderedHashmap *h;
1381         int r;
1382         const char *p;
1383
1384         assert(fname);
1385         assert(line >= 1);
1386         assert(buffer);
1387
1388         /* Parse columns */
1389         p = buffer;
1390         r = extract_many_words(&p, NULL, EXTRACT_QUOTES,
1391                                &action, &name, &id, &description, &home, &shell, NULL);
1392         if (r < 0) {
1393                 log_error("[%s:%u] Syntax error.", fname, line);
1394                 return r;
1395         }
1396         if (r < 2) {
1397                 log_error("[%s:%u] Missing action and name columns.", fname, line);
1398                 return -EINVAL;
1399         }
1400         if (!isempty(p)) {
1401                 log_error("[%s:%u] Trailing garbage.", fname, line);
1402                 return -EINVAL;
1403         }
1404
1405         /* Verify action */
1406         if (strlen(action) != 1) {
1407                 log_error("[%s:%u] Unknown modifier '%s'", fname, line, action);
1408                 return -EINVAL;
1409         }
1410
1411         if (!IN_SET(action[0], ADD_USER, ADD_GROUP, ADD_MEMBER, ADD_RANGE)) {
1412                 log_error("[%s:%u] Unknown command type '%c'.", fname, line, action[0]);
1413                 return -EBADMSG;
1414         }
1415
1416         /* Verify name */
1417         if (isempty(name) || streq(name, "-"))
1418                 name = mfree(name);
1419
1420         if (name) {
1421                 r = specifier_printf(name, specifier_table, NULL, &resolved_name);
1422                 if (r < 0) {
1423                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1424                         return r;
1425                 }
1426
1427                 if (!valid_user_group_name(resolved_name)) {
1428                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_name);
1429                         return -EINVAL;
1430                 }
1431         }
1432
1433         /* Verify id */
1434         if (isempty(id) || streq(id, "-"))
1435                 id = mfree(id);
1436
1437         if (id) {
1438                 r = specifier_printf(id, specifier_table, NULL, &resolved_id);
1439                 if (r < 0) {
1440                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, name);
1441                         return r;
1442                 }
1443         }
1444
1445         /* Verify description */
1446         if (isempty(description) || streq(description, "-"))
1447                 description = mfree(description);
1448
1449         if (description) {
1450                 r = specifier_printf(description, specifier_table, NULL, &resolved_description);
1451                 if (r < 0) {
1452                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, description);
1453                         return r;
1454                 }
1455
1456                 if (!valid_gecos(resolved_description)) {
1457                         log_error("[%s:%u] '%s' is not a valid GECOS field.", fname, line, resolved_description);
1458                         return -EINVAL;
1459                 }
1460         }
1461
1462         /* Verify home */
1463         if (isempty(home) || streq(home, "-"))
1464                 home = mfree(home);
1465
1466         if (home) {
1467                 r = specifier_printf(home, specifier_table, NULL, &resolved_home);
1468                 if (r < 0) {
1469                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, home);
1470                         return r;
1471                 }
1472
1473                 if (!valid_home(resolved_home)) {
1474                         log_error("[%s:%u] '%s' is not a valid home directory field.", fname, line, resolved_home);
1475                         return -EINVAL;
1476                 }
1477         }
1478
1479         /* Verify shell */
1480         if (isempty(shell) || streq(shell, "-"))
1481                 shell = mfree(shell);
1482
1483         if (shell) {
1484                 r = specifier_printf(shell, specifier_table, NULL, &resolved_shell);
1485                 if (r < 0) {
1486                         log_error("[%s:%u] Failed to replace specifiers: %s", fname, line, shell);
1487                         return r;
1488                 }
1489
1490                 if (!valid_shell(resolved_shell)) {
1491                         log_error("[%s:%u] '%s' is not a valid login shell field.", fname, line, resolved_shell);
1492                         return -EINVAL;
1493                 }
1494         }
1495
1496         switch (action[0]) {
1497
1498         case ADD_RANGE:
1499                 if (resolved_name) {
1500                         log_error("[%s:%u] Lines of type 'r' don't take a name field.", fname, line);
1501                         return -EINVAL;
1502                 }
1503
1504                 if (!resolved_id) {
1505                         log_error("[%s:%u] Lines of type 'r' require a ID range in the third field.", fname, line);
1506                         return -EINVAL;
1507                 }
1508
1509                 if (description || home || shell) {
1510                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1511                                   fname, line, action[0],
1512                                   description ? "GECOS" : home ? "home directory" : "login shell");
1513                         return -EINVAL;
1514                 }
1515
1516                 r = uid_range_add_str(&uid_range, &n_uid_range, resolved_id);
1517                 if (r < 0) {
1518                         log_error("[%s:%u] Invalid UID range %s.", fname, line, resolved_id);
1519                         return -EINVAL;
1520                 }
1521
1522                 return 0;
1523
1524         case ADD_MEMBER: {
1525                 char **l;
1526
1527                 /* Try to extend an existing member or group item */
1528                 if (!name) {
1529                         log_error("[%s:%u] Lines of type 'm' require a user name in the second field.", fname, line);
1530                         return -EINVAL;
1531                 }
1532
1533                 if (!resolved_id) {
1534                         log_error("[%s:%u] Lines of type 'm' require a group name in the third field.", fname, line);
1535                         return -EINVAL;
1536                 }
1537
1538                 if (!valid_user_group_name(resolved_id)) {
1539                         log_error("[%s:%u] '%s' is not a valid user or group name.", fname, line, resolved_id);
1540                         return -EINVAL;
1541                 }
1542
1543                 if (description || home || shell) {
1544                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1545                                   fname, line, action[0],
1546                                   description ? "GECOS" : home ? "home directory" : "login shell");
1547                         return -EINVAL;
1548                 }
1549
1550                 r = ordered_hashmap_ensure_allocated(&members, &string_hash_ops);
1551                 if (r < 0)
1552                         return log_oom();
1553
1554                 l = ordered_hashmap_get(members, resolved_id);
1555                 if (l) {
1556                         /* A list for this group name already exists, let's append to it */
1557                         r = strv_push(&l, resolved_name);
1558                         if (r < 0)
1559                                 return log_oom();
1560
1561                         resolved_name = NULL;
1562
1563                         assert_se(ordered_hashmap_update(members, resolved_id, l) >= 0);
1564                 } else {
1565                         /* No list for this group name exists yet, create one */
1566
1567                         l = new0(char *, 2);
1568                         if (!l)
1569                                 return -ENOMEM;
1570
1571                         l[0] = resolved_name;
1572                         l[1] = NULL;
1573
1574                         r = ordered_hashmap_put(members, resolved_id, l);
1575                         if (r < 0) {
1576                                 free(l);
1577                                 return log_oom();
1578                         }
1579
1580                         resolved_id = resolved_name = NULL;
1581                 }
1582
1583                 return 0;
1584         }
1585
1586         case ADD_USER:
1587                 if (!name) {
1588                         log_error("[%s:%u] Lines of type 'u' require a user name in the second field.", fname, line);
1589                         return -EINVAL;
1590                 }
1591
1592                 r = ordered_hashmap_ensure_allocated(&users, &string_hash_ops);
1593                 if (r < 0)
1594                         return log_oom();
1595
1596                 i = new0(Item, 1);
1597                 if (!i)
1598                         return log_oom();
1599
1600                 if (resolved_id) {
1601                         if (path_is_absolute(resolved_id)) {
1602                                 i->uid_path = TAKE_PTR(resolved_id);
1603                                 path_simplify(i->uid_path, false);
1604                         } else {
1605                                 _cleanup_free_ char *uid = NULL, *gid = NULL;
1606                                 if (split_pair(resolved_id, ":", &uid, &gid) == 0) {
1607                                         r = parse_gid(gid, &i->gid);
1608                                         if (r < 0)
1609                                                 return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1610                                         i->gid_set = true;
1611                                         i->id_set_strict = true;
1612                                         free_and_replace(resolved_id, uid);
1613                                 }
1614                                 if (!streq(resolved_id, "-")) {
1615                                         r = parse_uid(resolved_id, &i->uid);
1616                                         if (r < 0)
1617                                                 return log_error_errno(r, "Failed to parse UID: '%s': %m", id);
1618                                         i->uid_set = true;
1619                                 }
1620                         }
1621                 }
1622
1623                 i->description = TAKE_PTR(resolved_description);
1624                 i->home = TAKE_PTR(resolved_home);
1625                 i->shell = TAKE_PTR(resolved_shell);
1626
1627                 h = users;
1628                 break;
1629
1630         case ADD_GROUP:
1631                 if (!name) {
1632                         log_error("[%s:%u] Lines of type 'g' require a user name in the second field.", fname, line);
1633                         return -EINVAL;
1634                 }
1635
1636                 if (description || home || shell) {
1637                         log_error("[%s:%u] Lines of type '%c' don't take a %s field.",
1638                                   fname, line, action[0],
1639                                   description ? "GECOS" : home ? "home directory" : "login shell");
1640                         return -EINVAL;
1641                 }
1642
1643                 r = ordered_hashmap_ensure_allocated(&groups, &string_hash_ops);
1644                 if (r < 0)
1645                         return log_oom();
1646
1647                 i = new0(Item, 1);
1648                 if (!i)
1649                         return log_oom();
1650
1651                 if (resolved_id) {
1652                         if (path_is_absolute(resolved_id)) {
1653                                 i->gid_path = TAKE_PTR(resolved_id);
1654                                 path_simplify(i->gid_path, false);
1655                         } else {
1656                                 r = parse_gid(resolved_id, &i->gid);
1657                                 if (r < 0)
1658                                         return log_error_errno(r, "Failed to parse GID: '%s': %m", id);
1659
1660                                 i->gid_set = true;
1661                         }
1662                 }
1663
1664                 h = groups;
1665                 break;
1666
1667         default:
1668                 return -EBADMSG;
1669         }
1670
1671         i->type = action[0];
1672         i->name = TAKE_PTR(resolved_name);
1673
1674         existing = ordered_hashmap_get(h, i->name);
1675         if (existing) {
1676
1677                 /* Two identical items are fine */
1678                 if (!item_equal(existing, i))
1679                         log_warning("Two or more conflicting lines for %s configured, ignoring.", i->name);
1680
1681                 return 0;
1682         }
1683
1684         r = ordered_hashmap_put(h, i->name, i);
1685         if (r < 0)
1686                 return log_oom();
1687
1688         i = NULL;
1689         return 0;
1690 }
1691
1692 static int read_config_file(const char *fn, bool ignore_enoent) {
1693         _cleanup_fclose_ FILE *rf = NULL;
1694         FILE *f = NULL;
1695         char line[LINE_MAX];
1696         unsigned v = 0;
1697         int r = 0;
1698
1699         assert(fn);
1700
1701         if (streq(fn, "-"))
1702                 f = stdin;
1703         else {
1704                 r = search_and_fopen(fn, "re", arg_root, (const char**) CONF_PATHS_STRV("sysusers.d"), &rf);
1705                 if (r < 0) {
1706                         if (ignore_enoent && r == -ENOENT)
1707                                 return 0;
1708
1709                         return log_error_errno(r, "Failed to open '%s', ignoring: %m", fn);
1710                 }
1711
1712                 f = rf;
1713         }
1714
1715         FOREACH_LINE(line, f, break) {
1716                 char *l;
1717                 int k;
1718
1719                 v++;
1720
1721                 l = strstrip(line);
1722                 if (IN_SET(*l, 0, '#'))
1723                         continue;
1724
1725                 k = parse_line(fn, v, l);
1726                 if (k < 0 && r == 0)
1727                         r = k;
1728         }
1729
1730         if (ferror(f)) {
1731                 log_error_errno(errno, "Failed to read from file %s: %m", fn);
1732                 if (r == 0)
1733                         r = -EIO;
1734         }
1735
1736         return r;
1737 }
1738
1739 static void free_database(Hashmap *by_name, Hashmap *by_id) {
1740         char *name;
1741
1742         for (;;) {
1743                 name = hashmap_first(by_id);
1744                 if (!name)
1745                         break;
1746
1747                 hashmap_remove(by_name, name);
1748
1749                 hashmap_steal_first_key(by_id);
1750                 free(name);
1751         }
1752
1753         while ((name = hashmap_steal_first_key(by_name)))
1754                 free(name);
1755
1756         hashmap_free(by_name);
1757         hashmap_free(by_id);
1758 }
1759
1760 static int cat_config(void) {
1761         _cleanup_strv_free_ char **files = NULL;
1762         int r;
1763
1764         r = conf_files_list_with_replacement(arg_root, CONF_PATHS_STRV("sysusers.d"), arg_replace, &files, NULL);
1765         if (r < 0)
1766                 return r;
1767
1768         (void) pager_open(arg_no_pager, false);
1769
1770         return cat_files(NULL, files, 0);
1771 }
1772
1773 static void help(void) {
1774         printf("%s [OPTIONS...] [CONFIGURATION FILE...]\n\n"
1775                "Creates system user accounts.\n\n"
1776                "  -h --help                 Show this help\n"
1777                "     --version              Show package version\n"
1778                "     --cat-config           Show configuration files\n"
1779                "     --root=PATH            Operate on an alternate filesystem root\n"
1780                "     --replace=PATH         Treat arguments as replacement for PATH\n"
1781                "     --inline               Treat arguments as configuration lines\n"
1782                "     --no-pager             Do not pipe output into a pager\n"
1783                , program_invocation_short_name);
1784 }
1785
1786 static int parse_argv(int argc, char *argv[]) {
1787
1788         enum {
1789                 ARG_VERSION = 0x100,
1790                 ARG_CAT_CONFIG,
1791                 ARG_ROOT,
1792                 ARG_REPLACE,
1793                 ARG_INLINE,
1794                 ARG_NO_PAGER,
1795         };
1796
1797         static const struct option options[] = {
1798                 { "help",       no_argument,       NULL, 'h'            },
1799                 { "version",    no_argument,       NULL, ARG_VERSION    },
1800                 { "cat-config", no_argument,       NULL, ARG_CAT_CONFIG },
1801                 { "root",       required_argument, NULL, ARG_ROOT       },
1802                 { "replace",    required_argument, NULL, ARG_REPLACE    },
1803                 { "inline",     no_argument,       NULL, ARG_INLINE     },
1804                 { "no-pager",   no_argument,       NULL, ARG_NO_PAGER   },
1805                 {}
1806         };
1807
1808         int c, r;
1809
1810         assert(argc >= 0);
1811         assert(argv);
1812
1813         while ((c = getopt_long(argc, argv, "h", options, NULL)) >= 0)
1814
1815                 switch (c) {
1816
1817                 case 'h':
1818                         help();
1819                         return 0;
1820
1821                 case ARG_VERSION:
1822                         return version();
1823
1824                 case ARG_CAT_CONFIG:
1825                         arg_cat_config = true;
1826                         break;
1827
1828                 case ARG_ROOT:
1829                         r = parse_path_argument_and_warn(optarg, true, &arg_root);
1830                         if (r < 0)
1831                                 return r;
1832                         break;
1833
1834                 case ARG_REPLACE:
1835                         if (!path_is_absolute(optarg) ||
1836                             !endswith(optarg, ".conf")) {
1837                                 log_error("The argument to --replace= must an absolute path to a config file");
1838                                 return -EINVAL;
1839                         }
1840
1841                         arg_replace = optarg;
1842                         break;
1843
1844                 case ARG_INLINE:
1845                         arg_inline = true;
1846                         break;
1847
1848                 case ARG_NO_PAGER:
1849                         arg_no_pager = true;
1850                         break;
1851
1852                 case '?':
1853                         return -EINVAL;
1854
1855                 default:
1856                         assert_not_reached("Unhandled option");
1857                 }
1858
1859         if (arg_replace && arg_cat_config) {
1860                 log_error("Option --replace= is not supported with --cat-config");
1861                 return -EINVAL;
1862         }
1863
1864         if (arg_replace && optind >= argc) {
1865                 log_error("When --replace= is given, some configuration items must be specified");
1866                 return -EINVAL;
1867         }
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 int main(int argc, char *argv[]) {
1920         _cleanup_close_ int lock = -1;
1921         Iterator iterator;
1922         int r;
1923         Item *i;
1924         char *n;
1925
1926         r = parse_argv(argc, argv);
1927         if (r <= 0)
1928                 goto finish;
1929
1930         log_set_target(LOG_TARGET_AUTO);
1931         log_parse_environment();
1932         log_open();
1933
1934         if (arg_cat_config) {
1935                 r = cat_config();
1936                 goto finish;
1937         }
1938
1939         umask(0022);
1940
1941         r = mac_selinux_init();
1942         if (r < 0) {
1943                 log_error_errno(r, "SELinux setup failed: %m");
1944                 goto finish;
1945         }
1946
1947         /* If command line arguments are specified along with --replace, read all
1948          * configuration files and insert the positional arguments at the specified
1949          * place. Otherwise, if command line arguments are specified, execute just
1950          * them, and finally, without --replace= or any positional arguments, just
1951          * read configuration and execute it.
1952          */
1953         if (arg_replace || optind >= argc)
1954                 r = read_config_files(argv + optind);
1955         else
1956                 r = parse_arguments(argv + optind);
1957         if (r < 0)
1958                 goto finish;
1959
1960         /* Let's tell nss-systemd not to synthesize the "root" and "nobody" entries for it, so that our detection
1961          * whether the names or UID/GID area already used otherwise doesn't get confused. After all, even though
1962          * nss-systemd synthesizes these users/groups, they should still appear in /etc/passwd and /etc/group, as the
1963          * synthesizing logic is merely supposed to be fallback for cases where we run with a completely unpopulated
1964          * /etc. */
1965         if (setenv("SYSTEMD_NSS_BYPASS_SYNTHETIC", "1", 1) < 0) {
1966                 r = log_error_errno(errno, "Failed to set SYSTEMD_NSS_BYPASS_SYNTHETIC environment variable: %m");
1967                 goto finish;
1968         }
1969
1970         if (!uid_range) {
1971                 /* Default to default range of 1..SYSTEM_UID_MAX */
1972                 r = uid_range_add(&uid_range, &n_uid_range, 1, SYSTEM_UID_MAX);
1973                 if (r < 0) {
1974                         log_oom();
1975                         goto finish;
1976                 }
1977         }
1978
1979         r = add_implicit();
1980         if (r < 0)
1981                 goto finish;
1982
1983         lock = take_etc_passwd_lock(arg_root);
1984         if (lock < 0) {
1985                 log_error_errno(lock, "Failed to take /etc/passwd lock: %m");
1986                 goto finish;
1987         }
1988
1989         r = load_user_database();
1990         if (r < 0) {
1991                 log_error_errno(r, "Failed to load user database: %m");
1992                 goto finish;
1993         }
1994
1995         r = load_group_database();
1996         if (r < 0) {
1997                 log_error_errno(r, "Failed to read group database: %m");
1998                 goto finish;
1999         }
2000
2001         ORDERED_HASHMAP_FOREACH(i, groups, iterator)
2002                 (void) process_item(i);
2003
2004         ORDERED_HASHMAP_FOREACH(i, users, iterator)
2005                 (void) process_item(i);
2006
2007         r = write_files();
2008         if (r < 0)
2009                 log_error_errno(r, "Failed to write files: %m");
2010
2011 finish:
2012         pager_close();
2013
2014         ordered_hashmap_free_with_destructor(groups, item_free);
2015         ordered_hashmap_free_with_destructor(users, item_free);
2016
2017         while ((n = ordered_hashmap_first_key(members))) {
2018                 strv_free(ordered_hashmap_steal_first(members));
2019                 free(n);
2020         }
2021         ordered_hashmap_free(members);
2022
2023         ordered_hashmap_free(todo_uids);
2024         ordered_hashmap_free(todo_gids);
2025
2026         free_database(database_user, database_uid);
2027         free_database(database_group, database_gid);
2028
2029         free(uid_range);
2030
2031         free(arg_root);
2032
2033         return r < 0 ? EXIT_FAILURE : EXIT_SUCCESS;
2034 }