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         fflush(f);
 138
 139         if (ferror(f) || rename(temp_path, u->state_file) < 0) {
 140                 r = -errno;
 141                 unlink(u->state_file);
 142                 unlink(temp_path);
 143         }
 144
 145         fclose(f);
 146         free(temp_path);
 147
 148 finish:
 149         if (r < 0)
 150                 log_error("Failed to save user data for %s: %s", u->name, strerror(-r));
 151
 152         return r;
 153 }
 154
 155 int user_load(User *u) {
 156         int r;
 157         char *display = NULL;
 158         Session *s = NULL;
 159
 160         assert(u);
 161
 162         r = parse_env_file(u->state_file, NEWLINE,
 163                            "CGROUP", &u->cgroup_path,
 164                            "RUNTIME", &u->runtime_path,
 165                            "SERVICE", &u->service,
 166                            "DISPLAY", &display,
 167                            NULL);
 168         if (r < 0) {
 169                 free(display);
 170
 171                 if (r == -ENOENT)
 172                         return 0;
 173
 174                 log_error("Failed to read %s: %s", u->state_file, strerror(-r));
 175                 return r;
 176         }
 177
 178         if (display) {
 179                 s = hashmap_get(u->manager->sessions, display);
 180                 free(display);
 181         }
 182
 183         if (s && s->display && display_is_local(s->display))
 184                 u->display = s;
 185
 186         return r;
 187 }
 188
 189 static int user_mkdir_runtime_path(User *u) {
 190         char *p;
 191         int r;
 192
 193         assert(u);
 194
 195         r = safe_mkdir("/run/user", 0755, 0, 0);
 196         if (r < 0) {
 197                 log_error("Failed to create /run/user: %s", strerror(-r));
 198                 return r;
 199         }
 200
 201         if (!u->runtime_path) {
 202                 p = strappend("/run/user/", u->name);
 203
 204                 if (!p) {
 205                         log_error("Out of memory");
 206                         return -ENOMEM;
 207                 }
 208         } else
 209                 p = u->runtime_path;
 210
 211         r = safe_mkdir(p, 0700, u->uid, u->gid);
 212         if (r < 0) {
 213                 log_error("Failed to create runtime directory %s: %s", p, strerror(-r));
 214                 free(p);
 215                 u->runtime_path = NULL;
 216                 return r;
 217         }
 218
 219         u->runtime_path = p;
 220         return 0;
 221 }
 222
 223 static int user_create_cgroup(User *u) {
 224         char **k;
 225         char *p;
 226         int r;
 227
 228         assert(u);
 229
 230         if (!u->cgroup_path) {
 231                 if (asprintf(&p, "%s/%s", u->manager->cgroup_path, u->name) < 0) {
 232                         log_error("Out of memory");
 233                         return -ENOMEM;
 234                 }
 235         } else
 236                 p = u->cgroup_path;
 237
 238         r = cg_create(SYSTEMD_CGROUP_CONTROLLER, p);
 239         if (r < 0) {
 240                 log_error("Failed to create cgroup "SYSTEMD_CGROUP_CONTROLLER":%s: %s", p, strerror(-r));
 241                 free(p);
 242                 u->cgroup_path = NULL;
 243                 return r;
 244         }
 245
 246         u->cgroup_path = p;
 247
 248         STRV_FOREACH(k, u->manager->controllers) {
 249                 r = cg_create(*k, p);
 250                 if (r < 0)
 251                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
 252         }
 253
 254         return 0;
 255 }
 256
 257 static int user_start_service(User *u) {
 258         assert(u);
 259
 260         return 0;
 261 }
 262
 263 int user_start(User *u) {
 264         int r;
 265
 266         assert(u);
 267
 268         if (u->started)
 269                 return 0;
 270
 271         log_info("New user %s logged in.", u->name);
 272
 273         /* Make XDG_RUNTIME_DIR */
 274         r = user_mkdir_runtime_path(u);
 275         if (r < 0)
 276                 return r;
 277
 278         /* Create cgroup */
 279         r = user_create_cgroup(u);
 280         if (r < 0)
 281                 return r;
 282
 283         /* Spawn user systemd */
 284         r = user_start_service(u);
 285         if (r < 0)
 286                 return r;
 287
 288         /* Save new user data */
 289         user_save(u);
 290
 291         dual_timestamp_get(&u->timestamp);
 292
 293         u->started = true;
 294
 295         user_send_signal(u, true);
 296
 297         return 0;
 298 }
 299
 300 static int user_stop_service(User *u) {
 301         assert(u);
 302
 303         if (!u->service)
 304                 return 0;
 305
 306         return 0;
 307 }
 308
 309 static int user_shall_kill(User *u) {
 310         assert(u);
 311
 312         if (!u->manager->kill_user_processes)
 313                 return false;
 314
 315         if (strv_contains(u->manager->kill_exclude_users, u->name))
 316                 return false;
 317
 318         if (strv_isempty(u->manager->kill_only_users))
 319                 return true;
 320
 321         return strv_contains(u->manager->kill_only_users, u->name);
 322 }
 323
 324 static int user_kill_cgroup(User *u) {
 325         int r;
 326         char **k;
 327
 328         assert(u);
 329
 330         if (!u->cgroup_path)
 331                 return 0;
 332
 333         cg_trim(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 334
 335         if (user_shall_kill(u)) {
 336
 337                 r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 338                 if (r < 0)
 339                         log_error("Failed to kill user cgroup: %s", strerror(-r));
 340         } else {
 341
 342                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 343                 if (r < 0)
 344                         log_error("Failed to check user cgroup: %s", strerror(-r));
 345                 else if (r > 0) {
 346                         r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
 347                         if (r < 0)
 348                                 log_error("Failed to delete user cgroup: %s", strerror(-r));
 349                 } else
 350                         r = -EBUSY;
 351         }
 352
 353         STRV_FOREACH(k, u->manager->controllers)
 354                 cg_trim(*k, u->cgroup_path, true);
 355
 356         free(u->cgroup_path);
 357         u->cgroup_path = NULL;
 358
 359         return r;
 360 }
 361
 362 static int user_remove_runtime_path(User *u) {
 363         int r;
 364
 365         assert(u);
 366
 367         if (!u->runtime_path)
 368                 return 0;
 369
 370         r = rm_rf(u->runtime_path, false, true);
 371         if (r < 0)
 372                 log_error("Failed to remove runtime directory %s: %s", u->runtime_path, strerror(-r));
 373
 374         free(u->runtime_path);
 375         u->runtime_path = NULL;
 376
 377         return r;
 378 }
 379
 380 int user_stop(User *u) {
 381         Session *s;
 382         int r = 0, k;
 383         assert(u);
 384
 385         if (u->started)
 386                 log_info("User %s logged out.", u->name);
 387
 388         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 389                 k = session_stop(s);
 390                 if (k < 0)
 391                         r = k;
 392         }
 393
 394         /* Kill systemd */
 395         k = user_stop_service(u);
 396         if (k < 0)
 397                 r = k;
 398
 399         /* Kill cgroup */
 400         k = user_kill_cgroup(u);
 401         if (k < 0)
 402                 r = k;
 403
 404         /* Kill XDG_RUNTIME_DIR */
 405         k = user_remove_runtime_path(u);
 406         if (k < 0)
 407                 r = k;
 408
 409         unlink(u->state_file);
 410         user_add_to_gc_queue(u);
 411
 412         if (u->started)
 413                 user_send_signal(u, false);
 414
 415         u->started = false;
 416
 417         return r;
 418 }
 419
 420 int user_get_idle_hint(User *u, dual_timestamp *t) {
 421         Session *s;
 422         bool idle_hint = true;
 423         dual_timestamp ts = { 0, 0 };
 424
 425         assert(u);
 426
 427         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 428                 dual_timestamp k;
 429                 int ih;
 430
 431                 ih = session_get_idle_hint(s, &k);
 432                 if (ih < 0)
 433                         return ih;
 434
 435                 if (!ih) {
 436                         if (!idle_hint) {
 437                                 if (k.monotonic < ts.monotonic)
 438                                         ts = k;
 439                         } else {
 440                                 idle_hint = false;
 441                                 ts = k;
 442                         }
 443                 } else if (idle_hint) {
 444
 445                         if (k.monotonic > ts.monotonic)
 446                                 ts = k;
 447                 }
 448         }
 449
 450         if (t)
 451                 *t = ts;
 452
 453         return idle_hint;
 454 }
 455
 456 int user_check_gc(User *u) {
 457         int r;
 458         char *p;
 459
 460         assert(u);
 461
 462         if (u->sessions)
 463                 return 1;
 464
 465         if (asprintf(&p, "/var/lib/systemd/linger/%s", u->name) < 0)
 466                 return -ENOMEM;
 467
 468         r = access(p, F_OK) >= 0;
 469         free(p);
 470
 471         if (r > 0)
 472                 return 1;
 473
 474         if (u->cgroup_path) {
 475                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 476                 if (r < 0)
 477                         return r;
 478
 479                 if (r <= 0)
 480                         return 1;
 481         }
 482
 483         return 0;
 484 }
 485
 486 void user_add_to_gc_queue(User *u) {
 487         assert(u);
 488
 489         if (u->in_gc_queue)
 490                 return;
 491
 492         LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
 493         u->in_gc_queue = true;
 494 }
 495
 496 UserState user_get_state(User *u) {
 497         Session *i;
 498
 499         assert(u);
 500
 501         if (!u->sessions)
 502                 return USER_LINGERING;
 503
 504         LIST_FOREACH(sessions_by_user, i, u->sessions)
 505                 if (session_is_active(i))
 506                         return USER_ACTIVE;
 507
 508         return USER_ONLINE;
 509 }
 510
 511 static const char* const user_state_table[_USER_STATE_MAX] = {
 512         [USER_OFFLINE] = "offline",
 513         [USER_LINGERING] = "lingering",
 514         [USER_ONLINE] = "online",
 515         [USER_ACTIVE] = "active"
 516 };
 517
 518 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);