src/login/logind-user.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2011 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 of the License, or
  11   (at your option) any later version.
  12
  13   systemd is distributed in the hope that it will be useful, but
  14   WITHOUT ANY WARRANTY; without even the implied warranty of
  15   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  16   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <string.h>
  23 #include <unistd.h>
  24 #include <errno.h>
  25
  26 #include "logind-user.h"
  27 #include "util.h"
  28 #include "mkdir.h"
  29 #include "cgroup-util.h"
  30 #include "hashmap.h"
  31 #include "strv.h"
  32
  33 User* user_new(Manager *m, uid_t uid, gid_t gid, const char *name) {
  34         User *u;
  35
  36         assert(m);
  37         assert(name);
  38
  39         u = new0(User, 1);
  40         if (!u)
  41                 return NULL;
  42
  43         u->name = strdup(name);
  44         if (!u->name) {
  45                 free(u);
  46                 return NULL;
  47         }
  48
  49         if (asprintf(&u->state_file, "/run/systemd/users/%lu", (unsigned long) uid) < 0) {
  50                 free(u->name);
  51                 free(u);
  52                 return NULL;
  53         }
  54
  55         if (hashmap_put(m->users, ULONG_TO_PTR((unsigned long) uid), u) < 0) {
  56                 free(u->state_file);
  57                 free(u->name);
  58                 free(u);
  59                 return NULL;
  60         }
  61
  62         u->manager = m;
  63         u->uid = uid;
  64         u->gid = gid;
  65
  66         return u;
  67 }
  68
  69 void user_free(User *u) {
  70         assert(u);
  71
  72         if (u->in_gc_queue)
  73                 LIST_REMOVE(User, gc_queue, u->manager->user_gc_queue, u);
  74
  75         while (u->sessions)
  76                 session_free(u->sessions);
  77
  78         free(u->cgroup_path);
  79
  80         free(u->service);
  81         free(u->runtime_path);
  82
  83         hashmap_remove(u->manager->users, ULONG_TO_PTR((unsigned long) u->uid));
  84
  85         free(u->name);
  86         free(u->state_file);
  87         free(u);
  88 }
  89
  90 int user_save(User *u) {
  91         FILE *f;
  92         int r;
  93         char *temp_path;
  94
  95         assert(u);
  96         assert(u->state_file);
  97
  98         if (!u->started)
  99                 return 0;
 100
 101         r = safe_mkdir("/run/systemd/users", 0755, 0, 0);
 102         if (r < 0)
 103                 goto finish;
 104
 105         r = fopen_temporary(u->state_file, &f, &temp_path);
 106         if (r < 0)
 107                 goto finish;
 108
 109         fchmod(fileno(f), 0644);
 110
 111         fprintf(f,
 112                 "# This is private data. Do not parse.\n"
 113                 "NAME=%s\n"
 114                 "STATE=%s\n",
 115                 u->name,
 116                 user_state_to_string(user_get_state(u)));
 117
 118         if (u->cgroup_path)
 119                 fprintf(f,
 120                         "CGROUP=%s\n",
 121                         u->cgroup_path);
 122
 123         if (u->runtime_path)
 124                 fprintf(f,
 125                         "RUNTIME=%s\n",
 126                         u->runtime_path);
 127
 128         if (u->service)
 129                 fprintf(f,
 130                         "SERVICE=%s\n",
 131                         u->service);
 132
 133         if (u->display)
 134                 fprintf(f,
 135                         "DISPLAY=%s\n",
 136                         u->display->id);
 137
 138         if (u->sessions) {
 139                 Session *i;
 140
 141                 fputs("SESSIONS=", f);
 142                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 143                         fprintf(f,
 144                                 "%s%c",
 145                                 i->id,
 146                                 i->sessions_by_user_next ? ' ' : '\n');
 147                 }
 148
 149                 fputs("SEATS=", f);
 150                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 151                         if (i->seat)
 152                                 fprintf(f,
 153                                         "%s%c",
 154                                         i->seat->id,
 155                                         i->sessions_by_user_next ? ' ' : '\n');
 156                 }
 157
 158                 fputs("ACTIVE_SESSIONS=", f);
 159                 LIST_FOREACH(sessions_by_user, i, u->sessions)
 160                         if (session_is_active(i))
 161                                 fprintf(f,
 162                                         "%lu%c",
 163                                         (unsigned long) i->user->uid,
 164                                         i->sessions_by_user_next ? ' ' : '\n');
 165
 166                 fputs("ACTIVE_SEATS=", f);
 167                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 168                         if (session_is_active(i) && i->seat)
 169                                 fprintf(f,
 170                                         "%s%c",
 171                                         i->seat->id,
 172                                         i->sessions_by_user_next ? ' ' : '\n');
 173                 }
 174         }
 175
 176         fflush(f);
 177
 178         if (ferror(f) || rename(temp_path, u->state_file) < 0) {
 179                 r = -errno;
 180                 unlink(u->state_file);
 181                 unlink(temp_path);
 182         }
 183
 184         fclose(f);
 185         free(temp_path);
 186
 187 finish:
 188         if (r < 0)
 189                 log_error("Failed to save user data for %s: %s", u->name, strerror(-r));
 190
 191         return r;
 192 }
 193
 194 int user_load(User *u) {
 195         int r;
 196         char *display = NULL;
 197         Session *s = NULL;
 198
 199         assert(u);
 200
 201         r = parse_env_file(u->state_file, NEWLINE,
 202                            "CGROUP", &u->cgroup_path,
 203                            "RUNTIME", &u->runtime_path,
 204                            "SERVICE", &u->service,
 205                            "DISPLAY", &display,
 206                            NULL);
 207         if (r < 0) {
 208                 free(display);
 209
 210                 if (r == -ENOENT)
 211                         return 0;
 212
 213                 log_error("Failed to read %s: %s", u->state_file, strerror(-r));
 214                 return r;
 215         }
 216
 217         if (display) {
 218                 s = hashmap_get(u->manager->sessions, display);
 219                 free(display);
 220         }
 221
 222         if (s && s->display && display_is_local(s->display))
 223                 u->display = s;
 224
 225         return r;
 226 }
 227
 228 static int user_mkdir_runtime_path(User *u) {
 229         char *p;
 230         int r;
 231
 232         assert(u);
 233
 234         r = safe_mkdir("/run/user", 0755, 0, 0);
 235         if (r < 0) {
 236                 log_error("Failed to create /run/user: %s", strerror(-r));
 237                 return r;
 238         }
 239
 240         if (!u->runtime_path) {
 241                 p = strappend("/run/user/", u->name);
 242
 243                 if (!p) {
 244                         log_error("Out of memory");
 245                         return -ENOMEM;
 246                 }
 247         } else
 248                 p = u->runtime_path;
 249
 250         r = safe_mkdir(p, 0700, u->uid, u->gid);
 251         if (r < 0) {
 252                 log_error("Failed to create runtime directory %s: %s", p, strerror(-r));
 253                 free(p);
 254                 u->runtime_path = NULL;
 255                 return r;
 256         }
 257
 258         u->runtime_path = p;
 259         return 0;
 260 }
 261
 262 static int user_create_cgroup(User *u) {
 263         char **k;
 264         char *p;
 265         int r;
 266
 267         assert(u);
 268
 269         if (!u->cgroup_path) {
 270                 if (asprintf(&p, "%s/%s", u->manager->cgroup_path, u->name) < 0) {
 271                         log_error("Out of memory");
 272                         return -ENOMEM;
 273                 }
 274         } else
 275                 p = u->cgroup_path;
 276
 277         r = cg_create(SYSTEMD_CGROUP_CONTROLLER, p);
 278         if (r < 0) {
 279                 log_error("Failed to create cgroup "SYSTEMD_CGROUP_CONTROLLER":%s: %s", p, strerror(-r));
 280                 free(p);
 281                 u->cgroup_path = NULL;
 282                 return r;
 283         }
 284
 285         u->cgroup_path = p;
 286
 287         STRV_FOREACH(k, u->manager->controllers) {
 288
 289                 if (strv_contains(u->manager->reset_controllers, *k))
 290                         continue;
 291
 292                 r = cg_create(*k, p);
 293                 if (r < 0)
 294                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
 295         }
 296
 297         return 0;
 298 }
 299
 300 static int user_start_service(User *u) {
 301         assert(u);
 302
 303         /* FIXME: Fill me in later ... */
 304
 305         return 0;
 306 }
 307
 308 int user_start(User *u) {
 309         int r;
 310
 311         assert(u);
 312
 313         if (u->started)
 314                 return 0;
 315
 316         log_debug("New user %s logged in.", u->name);
 317
 318         /* Make XDG_RUNTIME_DIR */
 319         r = user_mkdir_runtime_path(u);
 320         if (r < 0)
 321                 return r;
 322
 323         /* Create cgroup */
 324         r = user_create_cgroup(u);
 325         if (r < 0)
 326                 return r;
 327
 328         /* Spawn user systemd */
 329         r = user_start_service(u);
 330         if (r < 0)
 331                 return r;
 332
 333         dual_timestamp_get(&u->timestamp);
 334
 335         u->started = true;
 336
 337         /* Save new user data */
 338         user_save(u);
 339
 340         user_send_signal(u, true);
 341
 342         return 0;
 343 }
 344
 345 static int user_stop_service(User *u) {
 346         assert(u);
 347
 348         if (!u->service)
 349                 return 0;
 350
 351         return 0;
 352 }
 353
 354 static int user_shall_kill(User *u) {
 355         assert(u);
 356
 357         if (!u->manager->kill_user_processes)
 358                 return false;
 359
 360         if (strv_contains(u->manager->kill_exclude_users, u->name))
 361                 return false;
 362
 363         if (strv_isempty(u->manager->kill_only_users))
 364                 return true;
 365
 366         return strv_contains(u->manager->kill_only_users, u->name);
 367 }
 368
 369 static int user_terminate_cgroup(User *u) {
 370         int r;
 371         char **k;
 372
 373         assert(u);
 374
 375         if (!u->cgroup_path)
 376                 return 0;
 377
 378         cg_trim(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 379
 380         if (user_shall_kill(u)) {
 381
 382                 r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 383                 if (r < 0)
 384                         log_error("Failed to kill user cgroup: %s", strerror(-r));
 385         } else {
 386
 387                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 388                 if (r < 0)
 389                         log_error("Failed to check user cgroup: %s", strerror(-r));
 390                 else if (r > 0) {
 391                         r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
 392                         if (r < 0)
 393                                 log_error("Failed to delete user cgroup: %s", strerror(-r));
 394                 } else
 395                         r = -EBUSY;
 396         }
 397
 398         STRV_FOREACH(k, u->manager->controllers)
 399                 cg_trim(*k, u->cgroup_path, true);
 400
 401         free(u->cgroup_path);
 402         u->cgroup_path = NULL;
 403
 404         return r;
 405 }
 406
 407 static int user_remove_runtime_path(User *u) {
 408         int r;
 409
 410         assert(u);
 411
 412         if (!u->runtime_path)
 413                 return 0;
 414
 415         r = rm_rf(u->runtime_path, false, true, false);
 416         if (r < 0)
 417                 log_error("Failed to remove runtime directory %s: %s", u->runtime_path, strerror(-r));
 418
 419         free(u->runtime_path);
 420         u->runtime_path = NULL;
 421
 422         return r;
 423 }
 424
 425 int user_stop(User *u) {
 426         Session *s;
 427         int r = 0, k;
 428         assert(u);
 429
 430         if (u->started)
 431                 log_debug("User %s logged out.", u->name);
 432
 433         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 434                 k = session_stop(s);
 435                 if (k < 0)
 436                         r = k;
 437         }
 438
 439         /* Kill systemd */
 440         k = user_stop_service(u);
 441         if (k < 0)
 442                 r = k;
 443
 444         /* Kill cgroup */
 445         k = user_terminate_cgroup(u);
 446         if (k < 0)
 447                 r = k;
 448
 449         /* Kill XDG_RUNTIME_DIR */
 450         k = user_remove_runtime_path(u);
 451         if (k < 0)
 452                 r = k;
 453
 454         unlink(u->state_file);
 455         user_add_to_gc_queue(u);
 456
 457         if (u->started)
 458                 user_send_signal(u, false);
 459
 460         u->started = false;
 461
 462         return r;
 463 }
 464
 465 int user_get_idle_hint(User *u, dual_timestamp *t) {
 466         Session *s;
 467         bool idle_hint = true;
 468         dual_timestamp ts = { 0, 0 };
 469
 470         assert(u);
 471
 472         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 473                 dual_timestamp k;
 474                 int ih;
 475
 476                 ih = session_get_idle_hint(s, &k);
 477                 if (ih < 0)
 478                         return ih;
 479
 480                 if (!ih) {
 481                         if (!idle_hint) {
 482                                 if (k.monotonic < ts.monotonic)
 483                                         ts = k;
 484                         } else {
 485                                 idle_hint = false;
 486                                 ts = k;
 487                         }
 488                 } else if (idle_hint) {
 489
 490                         if (k.monotonic > ts.monotonic)
 491                                 ts = k;
 492                 }
 493         }
 494
 495         if (t)
 496                 *t = ts;
 497
 498         return idle_hint;
 499 }
 500
 501 int user_check_gc(User *u, bool drop_not_started) {
 502         int r;
 503         char *p;
 504
 505         assert(u);
 506
 507         if (drop_not_started && !u->started)
 508                 return 0;
 509
 510         if (u->sessions)
 511                 return 1;
 512
 513         if (asprintf(&p, "/var/lib/systemd/linger/%s", u->name) < 0)
 514                 return -ENOMEM;
 515
 516         r = access(p, F_OK) >= 0;
 517         free(p);
 518
 519         if (r > 0)
 520                 return 1;
 521
 522         if (u->cgroup_path) {
 523                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 524                 if (r < 0)
 525                         return r;
 526
 527                 if (r <= 0)
 528                         return 1;
 529         }
 530
 531         return 0;
 532 }
 533
 534 void user_add_to_gc_queue(User *u) {
 535         assert(u);
 536
 537         if (u->in_gc_queue)
 538                 return;
 539
 540         LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
 541         u->in_gc_queue = true;
 542 }
 543
 544 UserState user_get_state(User *u) {
 545         Session *i;
 546
 547         assert(u);
 548
 549         if (!u->sessions)
 550                 return USER_LINGERING;
 551
 552         LIST_FOREACH(sessions_by_user, i, u->sessions)
 553                 if (session_is_active(i))
 554                         return USER_ACTIVE;
 555
 556         return USER_ONLINE;
 557 }
 558
 559 int user_kill(User *u, int signo) {
 560         int r = 0, q;
 561         Set *pid_set = NULL;
 562
 563         assert(u);
 564
 565         if (!u->cgroup_path)
 566                 return -ESRCH;
 567
 568         pid_set = set_new(trivial_hash_func, trivial_compare_func);
 569         if (!pid_set)
 570                 return -ENOMEM;
 571
 572         q = cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, signo, false, true, false, pid_set);
 573         if (q < 0)
 574                 if (q != -EAGAIN && q != -ESRCH && q != -ENOENT)
 575                         r = q;
 576
 577         if (pid_set)
 578                 set_free(pid_set);
 579
 580         return r;
 581 }
 582
 583 static const char* const user_state_table[_USER_STATE_MAX] = {
 584         [USER_OFFLINE] = "offline",
 585         [USER_LINGERING] = "lingering",
 586         [USER_ONLINE] = "online",
 587         [USER_ACTIVE] = "active"
 588 };
 589
 590 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);