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         r = safe_mkdir("/run/systemd/users", 0755, 0, 0);
  98         if (r < 0)
  99                 goto finish;
 100
 101         r = fopen_temporary(u->state_file, &f, &temp_path);
 102         if (r < 0)
 103                 goto finish;
 104
 105         fchmod(fileno(f), 0644);
 106
 107         fprintf(f,
 108                 "# This is private data. Do not parse.\n"
 109                 "NAME=%s\n"
 110                 "STATE=%s\n",
 111                 u->name,
 112                 user_state_to_string(user_get_state(u)));
 113
 114         if (u->cgroup_path)
 115                 fprintf(f,
 116                         "CGROUP=%s\n",
 117                         u->cgroup_path);
 118
 119         if (u->runtime_path)
 120                 fprintf(f,
 121                         "RUNTIME=%s\n",
 122                         u->runtime_path);
 123
 124         if (u->service)
 125                 fprintf(f,
 126                         "SERVICE=%s\n",
 127                         u->service);
 128
 129         if (u->display)
 130                 fprintf(f,
 131                         "DISPLAY=%s\n",
 132                         u->display->id);
 133
 134         fflush(f);
 135
 136         if (ferror(f) || rename(temp_path, u->state_file) < 0) {
 137                 r = -errno;
 138                 unlink(u->state_file);
 139                 unlink(temp_path);
 140         }
 141
 142         fclose(f);
 143         free(temp_path);
 144
 145 finish:
 146         if (r < 0)
 147                 log_error("Failed to save user data for %s: %s", u->name, strerror(-r));
 148
 149         return r;
 150 }
 151
 152 int user_load(User *u) {
 153         int r;
 154         char *display = NULL;
 155         Session *s = NULL;
 156
 157         assert(u);
 158
 159         r = parse_env_file(u->state_file, NEWLINE,
 160                            "CGROUP", &u->cgroup_path,
 161                            "RUNTIME", &u->runtime_path,
 162                            "SERVICE", &u->service,
 163                            "DISPLAY", &display,
 164                            NULL);
 165         if (r < 0) {
 166                 free(display);
 167
 168                 if (r == -ENOENT)
 169                         return 0;
 170
 171                 log_error("Failed to read %s: %s", u->state_file, strerror(-r));
 172                 return r;
 173         }
 174
 175         if (display) {
 176                 s = hashmap_get(u->manager->sessions, display);
 177                 free(display);
 178         }
 179
 180         if (s && s->display && display_is_local(s->display))
 181                 u->display = s;
 182
 183         return r;
 184 }
 185
 186 static int user_mkdir_runtime_path(User *u) {
 187         char *p;
 188         int r;
 189
 190         assert(u);
 191
 192         r = safe_mkdir("/run/user", 0755, 0, 0);
 193         if (r < 0) {
 194                 log_error("Failed to create /run/user: %s", strerror(-r));
 195                 return r;
 196         }
 197
 198         if (!u->runtime_path) {
 199                 p = strappend("/run/user/", u->name);
 200
 201                 if (!p) {
 202                         log_error("Out of memory");
 203                         return -ENOMEM;
 204                 }
 205         } else
 206                 p = u->runtime_path;
 207
 208         r = safe_mkdir(p, 0700, u->uid, u->gid);
 209         if (r < 0) {
 210                 log_error("Failed to create runtime directory %s: %s", p, strerror(-r));
 211                 free(p);
 212                 u->runtime_path = NULL;
 213                 return r;
 214         }
 215
 216         u->runtime_path = p;
 217         return 0;
 218 }
 219
 220 static int user_create_cgroup(User *u) {
 221         char **k;
 222         char *p;
 223         int r;
 224
 225         assert(u);
 226
 227         if (!u->cgroup_path) {
 228                 if (asprintf(&p, "%s/%s", u->manager->cgroup_path, u->name) < 0) {
 229                         log_error("Out of memory");
 230                         return -ENOMEM;
 231                 }
 232         } else
 233                 p = u->cgroup_path;
 234
 235         r = cg_create(SYSTEMD_CGROUP_CONTROLLER, p);
 236         if (r < 0) {
 237                 log_error("Failed to create cgroup "SYSTEMD_CGROUP_CONTROLLER":%s: %s", p, strerror(-r));
 238                 free(p);
 239                 u->cgroup_path = NULL;
 240                 return r;
 241         }
 242
 243         u->cgroup_path = p;
 244
 245         STRV_FOREACH(k, u->manager->controllers) {
 246                 r = cg_create(*k, p);
 247                 if (r < 0)
 248                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
 249         }
 250
 251         return 0;
 252 }
 253
 254 static int user_start_service(User *u) {
 255         assert(u);
 256
 257         return 0;
 258 }
 259
 260 int user_start(User *u) {
 261         int r;
 262
 263         assert(u);
 264
 265         if (u->started)
 266                 return 0;
 267
 268         log_info("New user %s logged in.", u->name);
 269
 270         /* Make XDG_RUNTIME_DIR */
 271         r = user_mkdir_runtime_path(u);
 272         if (r < 0)
 273                 return r;
 274
 275         /* Create cgroup */
 276         r = user_create_cgroup(u);
 277         if (r < 0)
 278                 return r;
 279
 280         /* Spawn user systemd */
 281         r = user_start_service(u);
 282         if (r < 0)
 283                 return r;
 284
 285         /* Save new user data */
 286         user_save(u);
 287
 288         dual_timestamp_get(&u->timestamp);
 289
 290         u->started = true;
 291
 292         user_send_signal(u, true);
 293
 294         return 0;
 295 }
 296
 297 static int user_stop_service(User *u) {
 298         assert(u);
 299
 300         if (!u->service)
 301                 return 0;
 302
 303         return 0;
 304 }
 305
 306 static int user_shall_kill(User *u) {
 307         assert(u);
 308
 309         if (!u->manager->kill_user_processes)
 310                 return false;
 311
 312         if (strv_contains(u->manager->kill_exclude_users, u->name))
 313                 return false;
 314
 315         if (strv_isempty(u->manager->kill_only_users))
 316                 return true;
 317
 318         return strv_contains(u->manager->kill_only_users, u->name);
 319 }
 320
 321 static int user_kill_cgroup(User *u) {
 322         int r;
 323         char **k;
 324
 325         assert(u);
 326
 327         if (!u->cgroup_path)
 328                 return 0;
 329
 330         cg_trim(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 331
 332         if (user_shall_kill(u)) {
 333
 334                 r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 335                 if (r < 0)
 336                         log_error("Failed to kill user cgroup: %s", strerror(-r));
 337         } else {
 338
 339                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 340                 if (r < 0)
 341                         log_error("Failed to check user cgroup: %s", strerror(-r));
 342                 else if (r > 0) {
 343                         r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
 344                         if (r < 0)
 345                                 log_error("Failed to delete user cgroup: %s", strerror(-r));
 346                 } else
 347                         r = -EBUSY;
 348         }
 349
 350         STRV_FOREACH(k, u->manager->controllers)
 351                 cg_trim(*k, u->cgroup_path, true);
 352
 353         free(u->cgroup_path);
 354         u->cgroup_path = NULL;
 355
 356         return r;
 357 }
 358
 359 static int user_remove_runtime_path(User *u) {
 360         int r;
 361
 362         assert(u);
 363
 364         if (!u->runtime_path)
 365                 return 0;
 366
 367         r = rm_rf(u->runtime_path, false, true);
 368         if (r < 0)
 369                 log_error("Failed to remove runtime directory %s: %s", u->runtime_path, strerror(-r));
 370
 371         free(u->runtime_path);
 372         u->runtime_path = NULL;
 373
 374         return r;
 375 }
 376
 377 int user_stop(User *u) {
 378         Session *s;
 379         int r = 0, k;
 380         assert(u);
 381
 382         if (u->started)
 383                 log_info("User %s logged out.", u->name);
 384
 385         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 386                 k = session_stop(s);
 387                 if (k < 0)
 388                         r = k;
 389         }
 390
 391         /* Kill systemd */
 392         k = user_stop_service(u);
 393         if (k < 0)
 394                 r = k;
 395
 396         /* Kill cgroup */
 397         k = user_kill_cgroup(u);
 398         if (k < 0)
 399                 r = k;
 400
 401         /* Kill XDG_RUNTIME_DIR */
 402         k = user_remove_runtime_path(u);
 403         if (k < 0)
 404                 r = k;
 405
 406         unlink(u->state_file);
 407         user_add_to_gc_queue(u);
 408
 409         if (u->started)
 410                 user_send_signal(u, false);
 411
 412         u->started = false;
 413
 414         return r;
 415 }
 416
 417 int user_get_idle_hint(User *u, dual_timestamp *t) {
 418         Session *s;
 419         bool idle_hint = true;
 420         dual_timestamp ts = { 0, 0 };
 421
 422         assert(u);
 423
 424         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 425                 dual_timestamp k;
 426                 int ih;
 427
 428                 ih = session_get_idle_hint(s, &k);
 429                 if (ih < 0)
 430                         return ih;
 431
 432                 if (!ih) {
 433                         if (!idle_hint) {
 434                                 if (k.monotonic < ts.monotonic)
 435                                         ts = k;
 436                         } else {
 437                                 idle_hint = false;
 438                                 ts = k;
 439                         }
 440                 } else if (idle_hint) {
 441
 442                         if (k.monotonic > ts.monotonic)
 443                                 ts = k;
 444                 }
 445         }
 446
 447         if (t)
 448                 *t = ts;
 449
 450         return idle_hint;
 451 }
 452
 453 int user_check_gc(User *u) {
 454         int r;
 455         char *p;
 456
 457         assert(u);
 458
 459         if (u->sessions)
 460                 return 1;
 461
 462         if (asprintf(&p, "/var/lib/systemd/linger/%s", u->name) < 0)
 463                 return -ENOMEM;
 464
 465         r = access(p, F_OK) >= 0;
 466         free(p);
 467
 468         if (r > 0)
 469                 return 1;
 470
 471         if (u->cgroup_path) {
 472                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 473                 if (r < 0)
 474                         return r;
 475
 476                 if (r <= 0)
 477                         return 1;
 478         }
 479
 480         return 0;
 481 }
 482
 483 void user_add_to_gc_queue(User *u) {
 484         assert(u);
 485
 486         if (u->in_gc_queue)
 487                 return;
 488
 489         LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
 490         u->in_gc_queue = true;
 491 }
 492
 493 UserState user_get_state(User *u) {
 494         Session *i;
 495
 496         assert(u);
 497
 498         if (!u->sessions)
 499                 return USER_LINGERING;
 500
 501         LIST_FOREACH(sessions_by_user, i, u->sessions)
 502                 if (session_is_active(i))
 503                         return USER_ACTIVE;
 504
 505         return USER_ONLINE;
 506 }
 507
 508 static const char* const user_state_table[_USER_STATE_MAX] = {
 509         [USER_OFFLINE] = "offline",
 510         [USER_LINGERING] = "lingering",
 511         [USER_ONLINE] = "online",
 512         [USER_ACTIVE] = "active"
 513 };
 514
 515 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);