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/user/%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/user", 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;
 156
 157         assert(u);
 158
 159         r = parse_env_file(u->state_file, "r",
 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         s = hashmap_get(u->manager->sessions, display);
 176         free(display);
 177
 178         if (s && s->display && x11_display_is_local(s->display))
 179                 u->display = s;
 180
 181         return r;
 182 }
 183
 184 static int user_mkdir_runtime_path(User *u) {
 185         char *p;
 186         int r;
 187
 188         assert(u);
 189
 190         r = safe_mkdir("/run/user", 0755, 0, 0);
 191         if (r < 0) {
 192                 log_error("Failed to create /run/user: %s", strerror(-r));
 193                 return r;
 194         }
 195
 196         if (!u->runtime_path) {
 197                 p = strappend("/run/user/", u->name);
 198
 199                 if (!p) {
 200                         log_error("Out of memory");
 201                         return -ENOMEM;
 202                 }
 203         } else
 204                 p = u->runtime_path;
 205
 206         r = safe_mkdir(p, 0700, u->uid, u->gid);
 207         if (r < 0) {
 208                 log_error("Failed to create runtime directory %s: %s", p, strerror(-r));
 209                 free(p);
 210                 u->runtime_path = NULL;
 211                 return r;
 212         }
 213
 214         u->runtime_path = p;
 215         return 0;
 216 }
 217
 218 static int user_create_cgroup(User *u) {
 219         char **k;
 220         char *p;
 221         int r;
 222
 223         assert(u);
 224
 225         if (!u->cgroup_path) {
 226                 if (asprintf(&p, "%s/%s", u->manager->cgroup_path, u->name) < 0) {
 227                         log_error("Out of memory");
 228                         return -ENOMEM;
 229                 }
 230         } else
 231                 p = u->cgroup_path;
 232
 233         r = cg_create(SYSTEMD_CGROUP_CONTROLLER, p);
 234         if (r < 0) {
 235                 free(p);
 236                 u->cgroup_path = NULL;
 237                 log_error("Failed to create cgroup "SYSTEMD_CGROUP_CONTROLLER":%s: %s", p, strerror(-r));
 238                 return r;
 239         }
 240
 241         u->cgroup_path = p;
 242
 243         STRV_FOREACH(k, u->manager->controllers) {
 244                 r = cg_create(*k, p);
 245                 if (r < 0)
 246                         log_warning("Failed to create cgroup %s:%s: %s", *k, p, strerror(-r));
 247         }
 248
 249         return 0;
 250 }
 251
 252 static int user_start_service(User *u) {
 253         assert(u);
 254
 255         return 0;
 256 }
 257
 258 int user_start(User *u) {
 259         int r;
 260
 261         assert(u);
 262
 263         /* Make XDG_RUNTIME_DIR */
 264         r = user_mkdir_runtime_path(u);
 265         if (r < 0)
 266                 return r;
 267
 268         /* Create cgroup */
 269         r = user_create_cgroup(u);
 270         if (r < 0)
 271                 return r;
 272
 273         /* Spawn user systemd */
 274         r = user_start_service(u);
 275         if (r < 0)
 276                 return r;
 277
 278         /* Save new user data */
 279         user_save(u);
 280
 281         dual_timestamp_get(&u->timestamp);
 282
 283         return 0;
 284 }
 285
 286 static int user_stop_service(User *u) {
 287         assert(u);
 288
 289         if (!u->service)
 290                 return 0;
 291
 292         return 0;
 293 }
 294
 295 static int user_shall_kill(User *u) {
 296         assert(u);
 297
 298         return u->manager->kill_user_processes;
 299 }
 300
 301 static int user_kill_cgroup(User *u) {
 302         int r;
 303         char **k;
 304
 305         assert(u);
 306
 307         if (!u->cgroup_path)
 308                 return 0;
 309
 310         cg_trim(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 311
 312         if (user_shall_kill(u)) {
 313
 314                 r = cg_kill_recursive_and_wait(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 315                 if (r < 0)
 316                         log_error("Failed to kill user cgroup: %s", strerror(-r));
 317         } else {
 318
 319                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, true);
 320                 if (r < 0)
 321                         log_error("Failed to check user cgroup: %s", strerror(-r));
 322                 else if (r > 0) {
 323                         r = cg_delete(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path);
 324                         if (r < 0)
 325                                 log_error("Failed to delete user cgroup: %s", strerror(-r));
 326                 } else
 327                         r = -EBUSY;
 328         }
 329
 330         STRV_FOREACH(k, u->manager->controllers)
 331                 cg_trim(*k, u->cgroup_path, true);
 332
 333         free(u->cgroup_path);
 334         u->cgroup_path = NULL;
 335
 336         return r;
 337 }
 338
 339 static int user_remove_runtime_path(User *u) {
 340         int r;
 341
 342         assert(u);
 343
 344         if (!u->runtime_path)
 345                 return 0;
 346
 347         r = rm_rf(u->runtime_path, false, true);
 348         if (r < 0)
 349                 log_error("Failed to remove runtime directory %s: %s", u->runtime_path, strerror(-r));
 350
 351         free(u->runtime_path);
 352         u->runtime_path = NULL;
 353
 354         return r;
 355 }
 356
 357 int user_stop(User *u) {
 358         Session *s;
 359         int r = 0, k;
 360         assert(u);
 361
 362         LIST_FOREACH(sessions_by_user, s, u->sessions) {
 363                 k = session_stop(s);
 364                 if (k < 0)
 365                         r = k;
 366         }
 367
 368         /* Kill systemd */
 369         k = user_stop_service(u);
 370         if (k < 0)
 371                 r = k;
 372
 373         /* Kill cgroup */
 374         k = user_kill_cgroup(u);
 375         if (k < 0)
 376                 r = k;
 377
 378         /* Kill XDG_RUNTIME_DIR */
 379         k = user_remove_runtime_path(u);
 380         if (k < 0)
 381                 r = k;
 382
 383         unlink(u->state_file);
 384         user_add_to_gc_queue(u);
 385
 386         return r;
 387 }
 388
 389 int user_check_gc(User *u) {
 390         int r;
 391         char *p;
 392
 393         assert(u);
 394
 395         if (u->sessions)
 396                 return 1;
 397
 398         if (asprintf(&p, "/var/lib/systemd/linger/%s", u->name) < 0)
 399                 return -ENOMEM;
 400
 401         r = access(p, F_OK) >= 0;
 402         free(p);
 403
 404         if (r > 0)
 405                 return 1;
 406
 407         if (u->cgroup_path) {
 408                 r = cg_is_empty_recursive(SYSTEMD_CGROUP_CONTROLLER, u->cgroup_path, false);
 409                 if (r < 0)
 410                         return r;
 411
 412                 if (r <= 0)
 413                         return 1;
 414         }
 415
 416         return 0;
 417 }
 418
 419 void user_add_to_gc_queue(User *u) {
 420         assert(u);
 421
 422         if (u->in_gc_queue)
 423                 return;
 424
 425         LIST_PREPEND(User, gc_queue, u->manager->user_gc_queue, u);
 426         u->in_gc_queue = true;
 427 }
 428
 429 UserState user_get_state(User *u) {
 430         Session *i;
 431
 432         assert(u);
 433
 434         if (!u->sessions)
 435                 return USER_LINGERING;
 436
 437         LIST_FOREACH(sessions_by_user, i, u->sessions)
 438                 if (session_is_active(i))
 439                         return USER_ACTIVE;
 440
 441         return USER_ONLINE;
 442 }
 443
 444 static const char* const user_state_table[_USER_STATE_MAX] = {
 445         [USER_OFFLINE] = "offline",
 446         [USER_LINGERING] = "lingering",
 447         [USER_ONLINE] = "online",
 448         [USER_ACTIVE] = "active"
 449 };
 450
 451 DEFINE_STRING_TABLE_LOOKUP(user_state, UserState);