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