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 = mkdir_safe_label("/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                 bool first;
 141
 142                 fputs("SESSIONS=", f);
 143                 first = true;
 144                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 145                         if (first)
 146                                 first = false;
 147                         else
 148                                 fputc(' ', f);
 149
 150                         fputs(i->id, f);
 151                 }
 152
 153                 fputs("\nSEATS=", f);
 154                 first = true;
 155                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 156                         if (!i->seat)
 157                                 continue;
 158
 159                         if (first)
 160                                 first = false;
 161                         else
 162                                 fputc(' ', f);
 163
 164                         fputs(i->seat->id, f);
 165                 }
 166
 167                 fputs("\nACTIVE_SESSIONS=", f);
 168                 first = true;
 169                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 170                         if (!session_is_active(i))
 171                                 continue;
 172
 173                         if (first)
 174                                 first = false;
 175                         else
 176                                 fputc(' ', f);
 177
 178                         fputs(i->id, f);
 179                 }
 180
 181                 fputs("\nACTIVE_SEATS=", f);
 182                 first = true;
 183                 LIST_FOREACH(sessions_by_user, i, u->sessions) {
 184                         if (!session_is_active(i) || !i->seat)
 185                                 continue;
 186
 187                         if (first)
 188                                 first = false;
 189                         else
 190                                 fputs(i->seat->id, f);
 191                 }
 192                 fputc('\n', f);
 193         }
 194
 195         fflush(f);
 196
 197         if (ferror(f) || rename(temp_path, u->state_file) < 0) {
 198                 r = -errno;
 199                 unlink(u->state_file);
 200                 unlink(temp_path);
 201         }
 202
 203         fclose(f);
 204         free(temp_path);
 205
 206 finish:
 207         if (r < 0)
 208                 log_error("Failed to save user data for %s: %s", u->name, strerror(-r));
 209
 210         return r;
 211 }
 212
 213 int user_load(User *u) {
 214         int r;
 215         char *display = NULL;
 216         Session *s = NULL;
 217
 218         assert(u);
 219
 220         r = parse_env_file(u->state_file, NEWLINE,
 221                            "CGROUP", &u->cgroup_path,
 222                            "RUNTIME", &u->runtime_path,
 223                            "SERVICE", &u->service,
 224                            "DISPLAY", &display,
 225                            NULL);
 226         if (r < 0) {
 227                 free(display);
 228
 229                 if (r == -ENOENT)
 230                         return 0;
 231
 232                 log_error("Failed to read %s: %s", u->state_file, strerror(-r));
 233                 return r;
 234         }
 235
 236         if (display) {
 237                 s = hashmap_get(u->manager->sessions, display);
 238                 free(display);
 239         }
 240
 241         if (s && s->display && display_is_local(s->display))
 242                 u->display = s;
 243
 244         return r;
 245 }
 246
 247 static int user_mkdir_runtime_path(User *u) {
 248         char *p;
 249         int r;
 250
 251         assert(u);
 252
 253         r = mkdir_safe_label("/run/user", 0755, 0, 0);
 254         if (r < 0) {
 255                 log_error("Failed to create /run/user: %s", strerror(-r));
 256                 return r;
 257         }
 258
 259         if (!u->runtime_path) {
 260                 p = strappend("/run/user/", u->name);
 261
 262                 if (!p) {
 263                         log_error("Out of memory");
 264                         return -ENOMEM;
 265                 }
 266         } else
 267                 p = u->runtime_path;
 268
 269         r = mkdir_safe_label(p, 0700, u->uid, u->gid);
 270         if (r < 0) {
 271                 log_error("Failed to create runtime directory %s: %s", p, strerror(-r));
 272                 free(p);
 273                 u->runtime_path = NULL;
 274                 return r;
 275         }
 276
 277         u->runtime_path = p;
 278         return 0;
 279 }
 280
 281 static int user_create_cgroup(User *u) {
 282         char **k;
 283         char *p;
 284         int r;
 285
 286         assert(u);
 287
 288         if (!u->cgroup_path) {
 289                 if (asprintf(&p, "%s/%s", u->manager->cgroup_path, u->name) < 0) {
 290                         log_error("Out of memory");
 291                         return -ENOMEM;
 292                 }
 293         } else
 294                 p = u->cgroup_path;
 295
 296         r = cg_create(SYSTEMD_CGROUP_CONTROLLER, p);
 297         if (r < 0) {
 298                 log_error("Failed to create cgroup "SYSTEMD_CGROUP_CONTROLLER":%s: %s", p, strerror(-r));
 299                 free(p);
 300                 u->cgroup_path = NULL;
 301                 return r;
 302         }
 303
 304         u->cgroup_path = p;
 305
 306         STRV_FOREACH(k, u->manager->controllers) {
 307
 308                 if (strv_contains(u->manager->reset_controllers, *k))
 309                         continue;
 310
 311                 r = cg_create(*k, p);
 312                 if (r < 0)
 313                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
 314         }
 315
 316         return 0;
 317 }
 318
 319 static int user_start_service(User *u) {
 320         assert(u);
 321
 322         /* FIXME: Fill me in later ... */
 323
 324         return 0;
 325 }
 326
 327 int user_start(User *u) {
 328         int r;
 329
 330         assert(u);
 331
 332         if (u->started)
 333                 return 0;
 334
 335         log_debug("New user %s logged in.", u->name);
 336
 337         /* Make XDG_RUNTIME_DIR */
 338         r = user_mkdir_runtime_path(u);
 339         if (r < 0)
 340                 return r;
 341
 342         /* Create cgroup */
 343         r = user_create_cgroup(u);
 344         if (r < 0)
 345                 return r;
 346
 347         /* Spawn user systemd */
 348         r = user_start_service(u);
 349         if (r < 0)
 350                 return r;
 351
 352         dual_timestamp_get(&u->timestamp);
 353
 354         u->started = true;
 355
 356         /* Save new user data */
 357         user_save(u);
 358
 359         user_send_signal(u, true);
 360
 361         return 0;
 362 }
 363
 364 static int user_stop_service(User *u) {
 365         assert(u);
 366
 367         if (!u->service)
 368                 return 0;
 369
 370         return 0;
 371 }
 372
 373 static int user_shall_kill(User *u) {
 374         assert(u);
 375
 376         if (!u->manager->kill_user_processes)
 377                 return false;
 378
 379         if (strv_contains(u->manager->kill_exclude_users, u->name))
 380                 return false;
 381
 382         if (strv_isempty(u->manager->kill_only_users))
 383                 return true;
 384
 385         return strv_contains(u->manager->kill_only_users, u->name);
 386 }
 387
 388 static int user_terminate_cgroup(User *u) {
 389         int r;
 390         char **k;
 391
 392         assert(u);
 393
 394         if (!u->cgroup_path)
 395                 return 0;
 396
 397         cg_trim(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 398
 399         if (user_shall_kill(u)) {
 400
 401                 r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 402                 if (r < 0)
 403                         log_error("Failed to kill user cgroup: %s", strerror(-r));
 404         } else {
 405
 406                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 407                 if (r < 0)
 408                         log_error("Failed to check user cgroup: %s", strerror(-r));
 409                 else if (r > 0) {
 410                         r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
 411                         if (r < 0)
 412                                 log_error("Failed to delete user cgroup: %s", strerror(-r));
 413                 } else
 414                         r = -EBUSY;
 415         }
 416
 417         STRV_FOREACH(k, u->manager->controllers)
 418                 cg_trim(*k, u->cgroup_path, true);
 419
 420         free(u->cgroup_path);
 421         u->cgroup_path = NULL;
 422
 423         return r;
 424 }
 425
 426 static int user_remove_runtime_path(User *u) {
 427         int r;
 428
 429         assert(u);
 430
 431         if (!u->runtime_path)
 432                 return 0;
 433
 434         r = rm_rf(u->runtime_path, false, true, false);
 435         if (r < 0)
 436                 log_error("Failed to remove runtime directory %s: %s", u->runtime_path, strerror(-r));
 437
 438         free(u->runtime_path);
 439         u->runtime_path = NULL;
 440
 441         return r;
 442 }
 443
 444 int user_stop(User *u) {
 445         Session *s;
 446         int r = 0, k;
 447         assert(u);
 448
 449         if (u->started)
 450                 log_debug("User %s logged out.", u->name);
 451
 452         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 453                 k = session_stop(s);
 454                 if (k < 0)
 455                         r = k;
 456         }
 457
 458         /* Kill systemd */
 459         k = user_stop_service(u);
 460         if (k < 0)
 461                 r = k;
 462
 463         /* Kill cgroup */
 464         k = user_terminate_cgroup(u);
 465         if (k < 0)
 466                 r = k;
 467
 468         /* Kill XDG_RUNTIME_DIR */
 469         k = user_remove_runtime_path(u);
 470         if (k < 0)
 471                 r = k;
 472
 473         unlink(u->state_file);
 474         user_add_to_gc_queue(u);
 475
 476         if (u->started)
 477                 user_send_signal(u, false);
 478
 479         u->started = false;
 480
 481         return r;
 482 }
 483
 484 int user_get_idle_hint(User *u, dual_timestamp *t) {
 485         Session *s;
 486         bool idle_hint = true;
 487         dual_timestamp ts = { 0, 0 };
 488
 489         assert(u);
 490
 491         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 492                 dual_timestamp k;
 493                 int ih;
 494
 495                 ih = session_get_idle_hint(s, &k);
 496                 if (ih < 0)
 497                         return ih;
 498
 499                 if (!ih) {
 500                         if (!idle_hint) {
 501                                 if (k.monotonic < ts.monotonic)
 502                                         ts = k;
 503                         } else {
 504                                 idle_hint = false;
 505                                 ts = k;
 506                         }
 507                 } else if (idle_hint) {
 508
 509                         if (k.monotonic > ts.monotonic)
 510                                 ts = k;
 511                 }
 512         }
 513
 514         if (t)
 515                 *t = ts;
 516
 517         return idle_hint;
 518 }
 519
 520 int user_check_gc(User *u, bool drop_not_started) {
 521         int r;
 522         char *p;
 523
 524         assert(u);
 525
 526         if (drop_not_started && !u->started)
 527                 return 0;
 528
 529         if (u->sessions)
 530                 return 1;
 531
 532         if (asprintf(&p, "/var/lib/systemd/linger/%s", u->name) < 0)
 533                 return -ENOMEM;
 534
 535         r = access(p, F_OK) >= 0;
 536         free(p);
 537
 538         if (r > 0)
 539                 return 1;
 540
 541         if (u->cgroup_path) {
 542                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 543                 if (r < 0)
 544                         return r;
 545
 546                 if (r <= 0)
 547                         return 1;
 548         }
 549
 550         return 0;
 551 }
 552
 553 void user_add_to_gc_queue(User *u) {
 554         assert(u);
 555
 556         if (u->in_gc_queue)
 557                 return;
 558
 559         LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
 560         u->in_gc_queue = true;
 561 }
 562
 563 UserState user_get_state(User *u) {
 564         Session *i;
 565
 566         assert(u);
 567
 568         if (!u->sessions)
 569                 return USER_LINGERING;
 570
 571         LIST_FOREACH(sessions_by_user, i, u->sessions)
 572                 if (session_is_active(i))
 573                         return USER_ACTIVE;
 574
 575         return USER_ONLINE;
 576 }
 577
 578 int user_kill(User *u, int signo) {
 579         int r = 0, q;
 580         Set *pid_set = NULL;
 581
 582         assert(u);
 583
 584         if (!u->cgroup_path)
 585                 return -ESRCH;
 586
 587         pid_set = set_new(trivial_hash_func, trivial_compare_func);
 588         if (!pid_set)
 589                 return -ENOMEM;
 590
 591         q = cg_kill_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, signo, false, true, false, pid_set);
 592         if (q < 0)
 593                 if (q != -EAGAIN && q != -ESRCH && q != -ENOENT)
 594                         r = q;
 595
 596         if (pid_set)
 597                 set_free(pid_set);
 598
 599         return r;
 600 }
 601
 602 static const char* const user_state_table[_USER_STATE_MAX] = {
 603         [USER_OFFLINE] = "offline",
 604         [USER_LINGERING] = "lingering",
 605         [USER_ONLINE] = "online",
 606         [USER_ACTIVE] = "active"
 607 };
 608
 609 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);