src/login/pam_systemd.c

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2
   3 #include <endian.h>
   4 #include <errno.h>
   5 #include <fcntl.h>
   6 #include <pwd.h>
   7 #include <security/_pam_macros.h>
   8 #include <security/pam_ext.h>
   9 #include <security/pam_misc.h>
  10 #include <security/pam_modules.h>
  11 #include <security/pam_modutil.h>
  12 #include <sys/file.h>
  13
  14 #include "alloc-util.h"
  15 #include "audit-util.h"
  16 #include "bus-common-errors.h"
  17 #include "bus-error.h"
  18 #include "bus-util.h"
  19 #include "def.h"
  20 #include "fd-util.h"
  21 #include "fileio.h"
  22 #include "format-util.h"
  23 #include "hostname-util.h"
  24 #include "login-util.h"
  25 #include "macro.h"
  26 #include "parse-util.h"
  27 #include "process-util.h"
  28 #include "socket-util.h"
  29 #include "strv.h"
  30 #include "terminal-util.h"
  31 #include "util.h"
  32 #include "path-util.h"
  33 #include "cgroup-util.h"
  34
  35 static int parse_argv(
  36                 pam_handle_t *handle,
  37                 int argc, const char **argv,
  38                 const char **class,
  39                 const char **type,
  40                 bool *debug) {
  41
  42         unsigned i;
  43
  44         assert(argc >= 0);
  45         assert(argc == 0 || argv);
  46
  47         for (i = 0; i < (unsigned) argc; i++) {
  48                 if (startswith(argv[i], "class=")) {
  49                         if (class)
  50                                 *class = argv[i] + 6;
  51
  52                 } else if (startswith(argv[i], "type=")) {
  53                         if (type)
  54                                 *type = argv[i] + 5;
  55
  56                 } else if (streq(argv[i], "debug")) {
  57                         if (debug)
  58                                 *debug = true;
  59
  60                 } else if (startswith(argv[i], "debug=")) {
  61                         int k;
  62
  63                         k = parse_boolean(argv[i] + 6);
  64                         if (k < 0)
  65                                 pam_syslog(handle, LOG_WARNING, "Failed to parse debug= argument, ignoring.");
  66                         else if (debug)
  67                                 *debug = k;
  68
  69                 } else
  70                         pam_syslog(handle, LOG_WARNING, "Unknown parameter '%s', ignoring", argv[i]);
  71         }
  72
  73         return 0;
  74 }
  75
  76 static int get_user_data(
  77                 pam_handle_t *handle,
  78                 const char **ret_username,
  79                 struct passwd **ret_pw) {
  80
  81         const char *username = NULL;
  82         struct passwd *pw = NULL;
  83         int r;
  84
  85         assert(handle);
  86         assert(ret_username);
  87         assert(ret_pw);
  88
  89         r = pam_get_user(handle, &username, NULL);
  90         if (r != PAM_SUCCESS) {
  91                 pam_syslog(handle, LOG_ERR, "Failed to get user name.");
  92                 return r;
  93         }
  94
  95         if (isempty(username)) {
  96                 pam_syslog(handle, LOG_ERR, "User name not valid.");
  97                 return PAM_AUTH_ERR;
  98         }
  99
 100         pw = pam_modutil_getpwnam(handle, username);
 101         if (!pw) {
 102                 pam_syslog(handle, LOG_ERR, "Failed to get user data.");
 103                 return PAM_USER_UNKNOWN;
 104         }
 105
 106         *ret_pw = pw;
 107         *ret_username = username;
 108
 109         return PAM_SUCCESS;
 110 }
 111
 112 static int get_seat_from_display(const char *display, const char **seat, uint32_t *vtnr) {
 113         union sockaddr_union sa = {
 114                 .un.sun_family = AF_UNIX,
 115         };
 116         _cleanup_free_ char *p = NULL, *tty = NULL;
 117         _cleanup_close_ int fd = -1;
 118         struct ucred ucred;
 119         int v, r;
 120
 121         assert(display);
 122         assert(vtnr);
 123
 124         /* We deduce the X11 socket from the display name, then use
 125          * SO_PEERCRED to determine the X11 server process, ask for
 126          * the controlling tty of that and if it's a VC then we know
 127          * the seat and the virtual terminal. Sounds ugly, is only
 128          * semi-ugly. */
 129
 130         r = socket_from_display(display, &p);
 131         if (r < 0)
 132                 return r;
 133         strncpy(sa.un.sun_path, p, sizeof(sa.un.sun_path)-1);
 134
 135         fd = socket(AF_UNIX, SOCK_STREAM|SOCK_CLOEXEC, 0);
 136         if (fd < 0)
 137                 return -errno;
 138
 139         if (connect(fd, &sa.sa, SOCKADDR_UN_LEN(sa.un)) < 0)
 140                 return -errno;
 141
 142         r = getpeercred(fd, &ucred);
 143         if (r < 0)
 144                 return r;
 145
 146         r = get_ctty(ucred.pid, NULL, &tty);
 147         if (r < 0)
 148                 return r;
 149
 150         v = vtnr_from_tty(tty);
 151         if (v < 0)
 152                 return v;
 153         else if (v == 0)
 154                 return -ENOENT;
 155
 156         if (seat)
 157                 *seat = "seat0";
 158         *vtnr = (uint32_t) v;
 159
 160         return 0;
 161 }
 162
 163 static int append_session_memory_max(pam_handle_t *handle, sd_bus_message *m, const char *limit) {
 164         uint64_t val;
 165         int r;
 166
 167         if (isempty(limit))
 168                 return 0;
 169
 170         if (streq(limit, "infinity")) {
 171                 r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", (uint64_t)-1);
 172                 if (r < 0) {
 173                         pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 174                         return r;
 175                 }
 176         } else {
 177                 r = parse_percent(limit);
 178                 if (r >= 0) {
 179                         r = sd_bus_message_append(m, "(sv)", "MemoryMaxScale", "u", (uint32_t) (((uint64_t) UINT32_MAX * r) / 100U));
 180                         if (r < 0) {
 181                                 pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 182                                 return r;
 183                         }
 184                 } else {
 185                         r = parse_size(limit, 1024, &val);
 186                         if (r >= 0) {
 187                                 r = sd_bus_message_append(m, "(sv)", "MemoryMax", "t", val);
 188                                 if (r < 0) {
 189                                         pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 190                                         return r;
 191                                 }
 192                         } else
 193                                 pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.limit: %s, ignoring.", limit);
 194                 }
 195         }
 196
 197         return 0;
 198 }
 199
 200 static int append_session_tasks_max(pam_handle_t *handle, sd_bus_message *m, const char *limit)
 201 {
 202         uint64_t val;
 203         int r;
 204
 205         /* No need to parse "infinity" here, it will be set unconditionally later in manager_start_scope() */
 206         if (isempty(limit) || streq(limit, "infinity"))
 207                 return 0;
 208
 209         r = safe_atou64(limit, &val);
 210         if (r >= 0) {
 211                 r = sd_bus_message_append(m, "(sv)", "TasksMax", "t", val);
 212                 if (r < 0) {
 213                         pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 214                         return r;
 215                 }
 216         } else
 217                 pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.limit: %s, ignoring.", limit);
 218
 219         return 0;
 220 }
 221
 222 static int append_session_cg_weight(pam_handle_t *handle, sd_bus_message *m, const char *limit, const char *field) {
 223         uint64_t val;
 224         int r;
 225
 226         if (!isempty(limit)) {
 227                 r = cg_weight_parse(limit, &val);
 228                 if (r >= 0) {
 229                         r = sd_bus_message_append(m, "(sv)", field, "t", val);
 230                         if (r < 0) {
 231                                 pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 232                                 return r;
 233                         }
 234                 } else if (streq(field, "CPUWeight"))
 235                         pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.cpu_weight: %s, ignoring.", limit);
 236                 else
 237                         pam_syslog(handle, LOG_WARNING, "Failed to parse systemd.io_weight: %s, ignoring.", limit);
 238         }
 239
 240         return 0;
 241 }
 242
 243 static const char* getenv_harder(pam_handle_t *handle, const char *key, const char *fallback) {
 244         const char *v;
 245
 246         assert(handle);
 247         assert(key);
 248
 249         /* Looks for an environment variable, preferrably in the environment block associated with the specified PAM
 250          * handle, falling back to the process' block instead. */
 251
 252         v = pam_getenv(handle, key);
 253         if (!isempty(v))
 254                 return v;
 255
 256         v = getenv(key);
 257         if (!isempty(v))
 258                 return v;
 259
 260         return fallback;
 261 }
 262
 263 _public_ PAM_EXTERN int pam_sm_open_session(
 264                 pam_handle_t *handle,
 265                 int flags,
 266                 int argc, const char **argv) {
 267
 268         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 269         _cleanup_(sd_bus_message_unrefp) sd_bus_message *m = NULL, *reply = NULL;
 270         const char
 271                 *username, *id, *object_path, *runtime_path,
 272                 *service = NULL,
 273                 *tty = NULL, *display = NULL,
 274                 *remote_user = NULL, *remote_host = NULL,
 275                 *seat = NULL,
 276                 *type = NULL, *class = NULL,
 277                 *class_pam = NULL, *type_pam = NULL, *cvtnr = NULL, *desktop = NULL,
 278                 *memory_max = NULL, *tasks_max = NULL, *cpu_weight = NULL, *io_weight = NULL;
 279         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 280         int session_fd = -1, existing, r;
 281         bool debug = false, remote;
 282         struct passwd *pw;
 283         uint32_t vtnr = 0;
 284         uid_t original_uid;
 285
 286         assert(handle);
 287
 288         /* Make this a NOP on non-logind systems */
 289         if (!logind_running())
 290                 return PAM_SUCCESS;
 291
 292         if (parse_argv(handle,
 293                        argc, argv,
 294                        &class_pam,
 295                        &type_pam,
 296                        &debug) < 0)
 297                 return PAM_SESSION_ERR;
 298
 299         if (debug)
 300                 pam_syslog(handle, LOG_DEBUG, "pam-systemd initializing");
 301
 302         r = get_user_data(handle, &username, &pw);
 303         if (r != PAM_SUCCESS) {
 304                 pam_syslog(handle, LOG_ERR, "Failed to get user data.");
 305                 return r;
 306         }
 307
 308         /* Make sure we don't enter a loop by talking to
 309          * systemd-logind when it is actually waiting for the
 310          * background to finish start-up. If the service is
 311          * "systemd-user" we simply set XDG_RUNTIME_DIR and
 312          * leave. */
 313
 314         pam_get_item(handle, PAM_SERVICE, (const void**) &service);
 315         if (streq_ptr(service, "systemd-user")) {
 316                 _cleanup_free_ char *rt = NULL;
 317
 318                 if (asprintf(&rt, "/run/user/"UID_FMT, pw->pw_uid) < 0)
 319                         return PAM_BUF_ERR;
 320
 321                 r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", rt, 0);
 322                 if (r != PAM_SUCCESS) {
 323                         pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
 324                         return r;
 325                 }
 326
 327                 return PAM_SUCCESS;
 328         }
 329
 330         /* Otherwise, we ask logind to create a session for us */
 331
 332         pam_get_item(handle, PAM_XDISPLAY, (const void**) &display);
 333         pam_get_item(handle, PAM_TTY, (const void**) &tty);
 334         pam_get_item(handle, PAM_RUSER, (const void**) &remote_user);
 335         pam_get_item(handle, PAM_RHOST, (const void**) &remote_host);
 336
 337         seat = getenv_harder(handle, "XDG_SEAT", NULL);
 338         cvtnr = getenv_harder(handle, "XDG_VTNR", NULL);
 339         type = getenv_harder(handle, "XDG_SESSION_TYPE", type_pam);
 340         class = getenv_harder(handle, "XDG_SESSION_CLASS", class_pam);
 341         desktop = getenv_harder(handle, "XDG_SESSION_DESKTOP", NULL);
 342
 343         tty = strempty(tty);
 344
 345         if (strchr(tty, ':')) {
 346                 /* A tty with a colon is usually an X11 display, placed there to show up in utmp. We rearrange things
 347                  * and don't pretend that an X display was a tty. */
 348                 if (isempty(display))
 349                         display = tty;
 350                 tty = NULL;
 351
 352         } else if (streq(tty, "cron")) {
 353                 /* cron is setting PAM_TTY to "cron" for some reason (the commit carries no information why, but
 354                  * probably because it wants to set it to something as pam_time/pam_access/… require PAM_TTY to be set
 355                  * (as they otherwise even try to update it!) — but cron doesn't actually allocate a TTY for its forked
 356                  * off processes.) */
 357                 type = "unspecified";
 358                 class = "background";
 359                 tty = NULL;
 360
 361         } else if (streq(tty, "ssh")) {
 362                 /* ssh has been setting PAM_TTY to "ssh" (for the same reason as cron does this, see above. For further
 363                  * details look for "PAM_TTY_KLUDGE" in the openssh sources). */
 364                 type ="tty";
 365                 class = "user";
 366                 tty = NULL; /* This one is particularly sad, as this means that ssh sessions — even though usually
 367                              * associated with a pty — won't be tracked by their tty in logind. This is because ssh
 368                              * does the PAM session registration early for new connections, and registers a pty only
 369                              * much later (this is because it doesn't know yet if it needs one at all, as whether to
 370                              * register a pty or not is negotiated much later in the protocol). */
 371
 372         } else
 373                 /* Chop off leading /dev prefix that some clients specify, but others do not. */
 374                 tty = skip_dev_prefix(tty);
 375
 376         /* If this fails vtnr will be 0, that's intended */
 377         if (!isempty(cvtnr))
 378                 (void) safe_atou32(cvtnr, &vtnr);
 379
 380         if (!isempty(display) && !vtnr) {
 381                 if (isempty(seat))
 382                         get_seat_from_display(display, &seat, &vtnr);
 383                 else if (streq(seat, "seat0"))
 384                         get_seat_from_display(display, NULL, &vtnr);
 385         }
 386
 387         if (seat && !streq(seat, "seat0") && vtnr != 0) {
 388                 pam_syslog(handle, LOG_DEBUG, "Ignoring vtnr %"PRIu32" for %s which is not seat0", vtnr, seat);
 389                 vtnr = 0;
 390         }
 391
 392         if (isempty(type))
 393                 type = !isempty(display) ? "x11" :
 394                            !isempty(tty) ? "tty" : "unspecified";
 395
 396         if (isempty(class))
 397                 class = streq(type, "unspecified") ? "background" : "user";
 398
 399         remote = !isempty(remote_host) && !is_localhost(remote_host);
 400
 401         (void) pam_get_data(handle, "systemd.memory_max", (const void **)&memory_max);
 402         (void) pam_get_data(handle, "systemd.tasks_max",  (const void **)&tasks_max);
 403         (void) pam_get_data(handle, "systemd.cpu_weight", (const void **)&cpu_weight);
 404         (void) pam_get_data(handle, "systemd.io_weight",  (const void **)&io_weight);
 405
 406         /* Talk to logind over the message bus */
 407
 408         r = sd_bus_open_system(&bus);
 409         if (r < 0) {
 410                 pam_syslog(handle, LOG_ERR, "Failed to connect to system bus: %s", strerror(-r));
 411                 return PAM_SESSION_ERR;
 412         }
 413
 414         if (debug) {
 415                 pam_syslog(handle, LOG_DEBUG, "Asking logind to create session: "
 416                            "uid="UID_FMT" pid="PID_FMT" service=%s type=%s class=%s desktop=%s seat=%s vtnr=%"PRIu32" tty=%s display=%s remote=%s remote_user=%s remote_host=%s",
 417                            pw->pw_uid, getpid_cached(),
 418                            strempty(service),
 419                            type, class, strempty(desktop),
 420                            strempty(seat), vtnr, strempty(tty), strempty(display),
 421                            yes_no(remote), strempty(remote_user), strempty(remote_host));
 422                 pam_syslog(handle, LOG_DEBUG, "Session limits: "
 423                            "memory_max=%s tasks_max=%s cpu_weight=%s io_weight=%s",
 424                            strna(memory_max), strna(tasks_max), strna(cpu_weight), strna(io_weight));
 425         }
 426
 427         r = sd_bus_message_new_method_call(
 428                         bus,
 429                         &m,
 430                         "org.freedesktop.login1",
 431                         "/org/freedesktop/login1",
 432                         "org.freedesktop.login1.Manager",
 433                         "CreateSession");
 434         if (r < 0) {
 435                 pam_syslog(handle, LOG_ERR, "Failed to create CreateSession method call: %s", strerror(-r));
 436                 return PAM_SESSION_ERR;
 437         }
 438
 439         r = sd_bus_message_append(m, "uusssssussbss",
 440                         (uint32_t) pw->pw_uid,
 441                         (uint32_t) getpid_cached(),
 442                         service,
 443                         type,
 444                         class,
 445                         desktop,
 446                         seat,
 447                         vtnr,
 448                         tty,
 449                         display,
 450                         remote,
 451                         remote_user,
 452                         remote_host);
 453         if (r < 0) {
 454                 pam_syslog(handle, LOG_ERR, "Failed to append to bus message: %s", strerror(-r));
 455                 return PAM_SESSION_ERR;
 456         }
 457
 458         r = sd_bus_message_open_container(m, 'a', "(sv)");
 459         if (r < 0) {
 460                 pam_syslog(handle, LOG_ERR, "Failed to open message container: %s", strerror(-r));
 461                 return PAM_SYSTEM_ERR;
 462         }
 463
 464         r = append_session_memory_max(handle, m, memory_max);
 465         if (r < 0)
 466                 return PAM_SESSION_ERR;
 467
 468         r = append_session_tasks_max(handle, m, tasks_max);
 469         if (r < 0)
 470                 return PAM_SESSION_ERR;
 471
 472         r = append_session_cg_weight(handle, m, cpu_weight, "CPUWeight");
 473         if (r < 0)
 474                 return PAM_SESSION_ERR;
 475
 476         r = append_session_cg_weight(handle, m, io_weight, "IOWeight");
 477         if (r < 0)
 478                 return PAM_SESSION_ERR;
 479
 480         r = sd_bus_message_close_container(m);
 481         if (r < 0) {
 482                 pam_syslog(handle, LOG_ERR, "Failed to close message container: %s", strerror(-r));
 483                 return PAM_SYSTEM_ERR;
 484         }
 485
 486         r = sd_bus_call(bus, m, 0, &error, &reply);
 487         if (r < 0) {
 488                 if (sd_bus_error_has_name(&error, BUS_ERROR_SESSION_BUSY)) {
 489                         pam_syslog(handle, LOG_DEBUG, "Cannot create session: %s", bus_error_message(&error, r));
 490                         return PAM_SUCCESS;
 491                 } else {
 492                         pam_syslog(handle, LOG_ERR, "Failed to create session: %s", bus_error_message(&error, r));
 493                         return PAM_SYSTEM_ERR;
 494                 }
 495         }
 496
 497         r = sd_bus_message_read(reply,
 498                                 "soshusub",
 499                                 &id,
 500                                 &object_path,
 501                                 &runtime_path,
 502                                 &session_fd,
 503                                 &original_uid,
 504                                 &seat,
 505                                 &vtnr,
 506                                 &existing);
 507         if (r < 0) {
 508                 pam_syslog(handle, LOG_ERR, "Failed to parse message: %s", strerror(-r));
 509                 return PAM_SESSION_ERR;
 510         }
 511
 512         if (debug)
 513                 pam_syslog(handle, LOG_DEBUG, "Reply from logind: "
 514                            "id=%s object_path=%s runtime_path=%s session_fd=%d seat=%s vtnr=%u original_uid=%u",
 515                            id, object_path, runtime_path, session_fd, seat, vtnr, original_uid);
 516
 517         r = pam_misc_setenv(handle, "XDG_SESSION_ID", id, 0);
 518         if (r != PAM_SUCCESS) {
 519                 pam_syslog(handle, LOG_ERR, "Failed to set session id.");
 520                 return r;
 521         }
 522
 523         if (original_uid == pw->pw_uid) {
 524                 /* Don't set $XDG_RUNTIME_DIR if the user we now
 525                  * authenticated for does not match the original user
 526                  * of the session. We do this in order not to result
 527                  * in privileged apps clobbering the runtime directory
 528                  * unnecessarily. */
 529
 530                 r = pam_misc_setenv(handle, "XDG_RUNTIME_DIR", runtime_path, 0);
 531                 if (r != PAM_SUCCESS) {
 532                         pam_syslog(handle, LOG_ERR, "Failed to set runtime dir.");
 533                         return r;
 534                 }
 535         }
 536
 537         if (!isempty(seat)) {
 538                 r = pam_misc_setenv(handle, "XDG_SEAT", seat, 0);
 539                 if (r != PAM_SUCCESS) {
 540                         pam_syslog(handle, LOG_ERR, "Failed to set seat.");
 541                         return r;
 542                 }
 543         }
 544
 545         if (vtnr > 0) {
 546                 char buf[DECIMAL_STR_MAX(vtnr)];
 547                 sprintf(buf, "%u", vtnr);
 548
 549                 r = pam_misc_setenv(handle, "XDG_VTNR", buf, 0);
 550                 if (r != PAM_SUCCESS) {
 551                         pam_syslog(handle, LOG_ERR, "Failed to set virtual terminal number.");
 552                         return r;
 553                 }
 554         }
 555
 556         r = pam_set_data(handle, "systemd.existing", INT_TO_PTR(!!existing), NULL);
 557         if (r != PAM_SUCCESS) {
 558                 pam_syslog(handle, LOG_ERR, "Failed to install existing flag.");
 559                 return r;
 560         }
 561
 562         if (session_fd >= 0) {
 563                 session_fd = fcntl(session_fd, F_DUPFD_CLOEXEC, 3);
 564                 if (session_fd < 0) {
 565                         pam_syslog(handle, LOG_ERR, "Failed to dup session fd: %m");
 566                         return PAM_SESSION_ERR;
 567                 }
 568
 569                 r = pam_set_data(handle, "systemd.session-fd", FD_TO_PTR(session_fd), NULL);
 570                 if (r != PAM_SUCCESS) {
 571                         pam_syslog(handle, LOG_ERR, "Failed to install session fd.");
 572                         safe_close(session_fd);
 573                         return r;
 574                 }
 575         }
 576
 577         return PAM_SUCCESS;
 578 }
 579
 580 _public_ PAM_EXTERN int pam_sm_close_session(
 581                 pam_handle_t *handle,
 582                 int flags,
 583                 int argc, const char **argv) {
 584
 585         _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
 586         _cleanup_(sd_bus_flush_close_unrefp) sd_bus *bus = NULL;
 587         const void *existing = NULL;
 588         const char *id;
 589         int r;
 590
 591         assert(handle);
 592
 593         /* Only release session if it wasn't pre-existing when we
 594          * tried to create it */
 595         pam_get_data(handle, "systemd.existing", &existing);
 596
 597         id = pam_getenv(handle, "XDG_SESSION_ID");
 598         if (id && !existing) {
 599
 600                 /* Before we go and close the FIFO we need to tell
 601                  * logind that this is a clean session shutdown, so
 602                  * that it doesn't just go and slaughter us
 603                  * immediately after closing the fd */
 604
 605                 r = sd_bus_open_system(&bus);
 606                 if (r < 0) {
 607                         pam_syslog(handle, LOG_ERR, "Failed to connect to system bus: %s", strerror(-r));
 608                         return PAM_SESSION_ERR;
 609                 }
 610
 611                 r = sd_bus_call_method(bus,
 612                                        "org.freedesktop.login1",
 613                                        "/org/freedesktop/login1",
 614                                        "org.freedesktop.login1.Manager",
 615                                        "ReleaseSession",
 616                                        &error,
 617                                        NULL,
 618                                        "s",
 619                                        id);
 620                 if (r < 0) {
 621                         pam_syslog(handle, LOG_ERR, "Failed to release session: %s", bus_error_message(&error, r));
 622                         return PAM_SESSION_ERR;
 623                 }
 624         }
 625
 626         /* Note that we are knowingly leaking the FIFO fd here. This
 627          * way, logind can watch us die. If we closed it here it would
 628          * not have any clue when that is completed. Given that one
 629          * cannot really have multiple PAM sessions open from the same
 630          * process this means we will leak one FD at max. */
 631
 632         return PAM_SUCCESS;
 633 }