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|
#include <config.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/wait.h>
#include <fcntl.h>
#include <pwd.h>
#include <grp.h>
#include <glib.h>
#include <security/pam_appl.h>
#include <utmp.h>
#include <utmpx.h>
#include <sys/mman.h>
#if HAVE_LIBAUDIT
#include <libaudit.h>
#endif
#include "configuration.h"
#include "session-child.h"
#include "session.h"
#include "console-kit.h"
#include "login1.h"
#include "log-file.h"
#include "privileges.h"
#include "x-authority.h"
#include "configuration.h"
/* Child process being run */
static GPid child_pid = 0;
/* Pipe to communicate with daemon */
static int from_daemon_output = 0;
static int to_daemon_input = 0;
static gboolean is_interactive;
static gboolean do_authenticate;
static gboolean authentication_complete = FALSE;
static pam_handle_t *pam_handle;
/* Maximum length of a string to pass between daemon and session */
#define MAX_STRING_LENGTH 65535
static void
write_data (const void *buf, size_t count)
{
if (write (to_daemon_input, buf, count) != count)
g_printerr ("Error writing to daemon: %s\n", strerror (errno));
}
static void
write_string (const char *value)
{
int length = value ? strlen (value) : -1;
write_data (&length, sizeof (length));
if (value)
write_data (value, sizeof (char) * length);
}
static ssize_t
read_data (void *buf, size_t count)
{
ssize_t n_read = read (from_daemon_output, buf, count);
if (n_read < 0)
g_printerr ("Error reading from daemon: %s\n", strerror (errno));
return n_read;
}
static gchar *
read_string_full (void* (*alloc_fn)(size_t n))
{
int length;
if (read_data (&length, sizeof (length)) <= 0)
return NULL;
if (length < 0)
return NULL;
if (length > MAX_STRING_LENGTH)
{
g_printerr ("Invalid string length %d from daemon\n", length);
return NULL;
}
gchar *value = (*alloc_fn) (sizeof (gchar) * (length + 1));
read_data (value, length);
value[length] = '\0';
return value;
}
static gchar *
read_string (void)
{
return read_string_full (g_malloc);
}
static int
pam_conv_cb (int msg_length, const struct pam_message **msg, struct pam_response **resp, void *app_data)
{
/* FIXME: We don't support communication after pam_authenticate completes */
if (authentication_complete)
return PAM_SUCCESS;
/* Cancel authentication if requiring input */
if (!is_interactive)
{
for (int i = 0; i < msg_length; i++)
{
if (msg[i]->msg_style == PAM_PROMPT_ECHO_ON || msg[i]->msg_style == PAM_PROMPT_ECHO_OFF)
{
g_printerr ("Stopping PAM conversation, interaction requested but not supported\n");
return PAM_CONV_ERR;
}
}
/* Ignore informational messages */
return PAM_SUCCESS;
}
/* Check if we changed user */
gchar *username = NULL;
pam_get_item (pam_handle, PAM_USER, (const void **) &username);
/* Notify the daemon */
write_string (username);
gboolean auth_complete = FALSE;
write_data (&auth_complete, sizeof (auth_complete));
write_data (&msg_length, sizeof (msg_length));
for (int i = 0; i < msg_length; i++)
{
const struct pam_message *m = msg[i];
write_data (&m->msg_style, sizeof (m->msg_style));
write_string (m->msg);
}
/* Get response */
int error;
read_data (&error, sizeof (error));
if (error != PAM_SUCCESS)
return error;
struct pam_response *response = calloc (msg_length, sizeof (struct pam_response));
for (int i = 0; i < msg_length; i++)
{
struct pam_response *r = &response[i];
// callers of this function inside pam will expect to be able to call
// free() on the strings we give back. So alloc with malloc.
r->resp = read_string_full (malloc);
read_data (&r->resp_retcode, sizeof (r->resp_retcode));
}
*resp = response;
return PAM_SUCCESS;
}
static void
signal_cb (int signum)
{
/* Pass on signal to child, otherwise just quit */
if (child_pid > 0)
kill (child_pid, signum);
else
exit (EXIT_SUCCESS);
}
static XAuthority *
read_xauth (void)
{
g_autofree gchar *x_authority_name = read_string ();
if (!x_authority_name)
return NULL;
guint16 x_authority_family;
read_data (&x_authority_family, sizeof (x_authority_family));
gsize x_authority_address_length;
read_data (&x_authority_address_length, sizeof (x_authority_address_length));
g_autofree guint8 *x_authority_address = g_malloc (x_authority_address_length);
read_data (x_authority_address, x_authority_address_length);
g_autofree gchar *x_authority_number = read_string ();
gsize x_authority_data_length;
read_data (&x_authority_data_length, sizeof (x_authority_data_length));
g_autofree guint8 *x_authority_data = g_malloc (x_authority_data_length);
read_data (x_authority_data, x_authority_data_length);
return x_authority_new (x_authority_family, x_authority_address, x_authority_address_length, x_authority_number, x_authority_name, x_authority_data, x_authority_data_length);
}
/* GNU provides this but we can't rely on that so let's make our own version */
static void
updwtmpx (const gchar *wtmp_file, struct utmpx *ut)
{
struct utmp u;
memset (&u, 0, sizeof (u));
u.ut_type = ut->ut_type;
u.ut_pid = ut->ut_pid;
if (ut->ut_line)
strncpy (u.ut_line, ut->ut_line, sizeof (u.ut_line));
if (ut->ut_id)
strncpy (u.ut_id, ut->ut_id, sizeof (u.ut_id));
if (ut->ut_user)
strncpy (u.ut_user, ut->ut_user, sizeof (u.ut_user));
if (ut->ut_host)
strncpy (u.ut_host, ut->ut_host, sizeof (u.ut_host));
u.ut_tv.tv_sec = ut->ut_tv.tv_sec;
u.ut_tv.tv_usec = ut->ut_tv.tv_usec;
updwtmp (wtmp_file, &u);
}
#if HAVE_LIBAUDIT
static void
audit_event (int type, const gchar *username, uid_t uid, const gchar *remote_host_name, const gchar *tty, gboolean success)
{
int auditfd = audit_open ();
if (auditfd < 0) {
g_printerr ("Error opening audit socket: %s\n", strerror (errno));
return;
}
const char *op = NULL;
if (type == AUDIT_USER_LOGIN)
op = "login";
else if (type == AUDIT_USER_LOGOUT)
op = "logout";
int result = success == TRUE ? 1 : 0;
if (audit_log_acct_message (auditfd, type, NULL, op, username, uid, remote_host_name, NULL, tty, result) <= 0)
g_printerr ("Error writing audit message: %s\n", strerror (errno));
close (auditfd);
}
#endif
int
session_child_run (int argc, char **argv)
{
#if !defined(GLIB_VERSION_2_36)
g_type_init ();
#endif
if (config_get_boolean (config_get_instance (), "LightDM", "lock-memory"))
{
/* Protect memory from being paged to disk, as we deal with passwords */
mlockall (MCL_CURRENT | MCL_FUTURE);
}
/* Make input non-blocking */
int fd = open ("/dev/null", O_RDONLY);
dup2 (fd, STDIN_FILENO);
close (fd);
/* Close stdout */
fd = open ("/dev/null", O_WRONLY);
dup2 (fd, STDOUT_FILENO);
close (fd);
/* Get the pipe from the daemon */
if (argc != 4)
{
g_printerr ("Usage: lightdm --session-child INPUTFD OUTPUTFD\n");
return EXIT_FAILURE;
}
from_daemon_output = atoi (argv[2]);
to_daemon_input = atoi (argv[3]);
if (from_daemon_output == 0 || to_daemon_input == 0)
{
g_printerr ("Invalid file descriptors %s %s\n", argv[2], argv[3]);
return EXIT_FAILURE;
}
/* Don't let these pipes leak to the command we will run */
fcntl (from_daemon_output, F_SETFD, FD_CLOEXEC);
fcntl (to_daemon_input, F_SETFD, FD_CLOEXEC);
/* Read a version number so we can handle upgrades (i.e. a newer version of session child is run for an old daemon */
int version;
read_data (&version, sizeof (version));
g_autofree gchar *service = read_string ();
g_autofree gchar *username = read_string ();
read_data (&do_authenticate, sizeof (do_authenticate));
read_data (&is_interactive, sizeof (is_interactive));
g_autofree gchar *unused_class = read_string (); /* Used to be class, now we just use the environment variable */
g_autofree gchar *tty = read_string ();
g_autofree gchar *remote_host_name = read_string ();
g_autofree gchar *xdisplay = read_string ();
g_autoptr(XAuthority) x_authority = read_xauth ();
/* Setup PAM */
struct pam_conv conversation = { pam_conv_cb, NULL };
int result = pam_start (service, username, &conversation, &pam_handle);
if (result != PAM_SUCCESS)
{
g_printerr ("Failed to start PAM: %s", pam_strerror (NULL, result));
return EXIT_FAILURE;
}
if (xdisplay)
{
#ifdef PAM_XDISPLAY
pam_set_item (pam_handle, PAM_XDISPLAY, xdisplay);
#endif
pam_set_item (pam_handle, PAM_TTY, xdisplay);
}
else if (tty)
pam_set_item (pam_handle, PAM_TTY, tty);
#ifdef PAM_XAUTHDATA
if (x_authority)
{
struct pam_xauth_data value;
value.name = (char *) x_authority_get_authorization_name (x_authority);
value.namelen = strlen (x_authority_get_authorization_name (x_authority));
value.data = (char *) x_authority_get_authorization_data (x_authority);
value.datalen = x_authority_get_authorization_data_length (x_authority);
pam_set_item (pam_handle, PAM_XAUTHDATA, &value);
}
#endif
/* Authenticate */
int authentication_result = PAM_SUCCESS;
if (do_authenticate)
{
const gchar *new_username;
authentication_result = pam_authenticate (pam_handle, 0);
/* See what user we ended up as */
if (pam_get_item (pam_handle, PAM_USER, (const void **) &new_username) != PAM_SUCCESS)
{
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
g_free (username);
username = g_strdup (new_username);
/* Write record to btmp database */
if (authentication_result == PAM_AUTH_ERR)
{
struct utmpx ut;
struct timeval tv;
memset (&ut, 0, sizeof (ut));
ut.ut_type = USER_PROCESS;
ut.ut_pid = getpid ();
if (xdisplay)
strncpy (ut.ut_id, xdisplay, sizeof (ut.ut_id));
if (tty && g_str_has_prefix (tty, "/dev/"))
strncpy (ut.ut_line, tty + strlen ("/dev/"), sizeof (ut.ut_line));
strncpy (ut.ut_user, username, sizeof (ut.ut_user));
if (xdisplay)
strncpy (ut.ut_host, xdisplay, sizeof (ut.ut_host));
else if (remote_host_name)
strncpy (ut.ut_host, remote_host_name, sizeof (ut.ut_host));
gettimeofday (&tv, NULL);
ut.ut_tv.tv_sec = tv.tv_sec;
ut.ut_tv.tv_usec = tv.tv_usec;
updwtmpx ("/var/log/btmp", &ut);
#if HAVE_LIBAUDIT
audit_event (AUDIT_USER_LOGIN, username, -1, remote_host_name, tty, FALSE);
#endif
}
/* Check account is valid */
if (authentication_result == PAM_SUCCESS)
authentication_result = pam_acct_mgmt (pam_handle, 0);
if (authentication_result == PAM_NEW_AUTHTOK_REQD)
authentication_result = pam_chauthtok (pam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
}
else
authentication_result = PAM_SUCCESS;
authentication_complete = TRUE;
User *user = NULL;
if (authentication_result == PAM_SUCCESS)
{
/* Fail authentication if user doesn't actually exist */
user = accounts_get_user_by_name (username);
if (!user)
{
g_printerr ("Failed to get information on user %s: %s\n", username, strerror (errno));
authentication_result = PAM_USER_UNKNOWN;
}
else
{
/* Set POSIX variables */
pam_putenv (pam_handle, "PATH=/usr/local/bin:/usr/bin:/bin");
pam_putenv (pam_handle, g_strdup_printf ("USER=%s", username));
pam_putenv (pam_handle, g_strdup_printf ("LOGNAME=%s", username));
pam_putenv (pam_handle, g_strdup_printf ("HOME=%s", user_get_home_directory (user)));
pam_putenv (pam_handle, g_strdup_printf ("SHELL=%s", user_get_shell (user)));
/* Let the greeter and user session inherit the system default locale */
static const gchar * const locale_var_names[] = {
"LC_PAPER",
"LC_NAME",
"LC_ADDRESS",
"LC_TELEPHONE",
"LC_MEASUREMENT",
"LC_IDENTIFICATION",
"LC_COLLATE",
"LC_CTYPE",
"LC_MONETARY",
"LC_NUMERIC",
"LC_TIME",
"LC_MESSAGES",
"LC_ALL",
"LANG",
NULL
};
for (int i = 0; locale_var_names[i] != NULL; i++)
{
const gchar *locale_value;
if ((locale_value = g_getenv (locale_var_names[i])) != NULL)
{
g_autofree gchar *locale_var = g_strdup_printf ("%s=%s", locale_var_names[i], locale_value);
pam_putenv (pam_handle, locale_var);
}
}
}
}
g_autofree gchar *authentication_result_string = g_strdup (pam_strerror (pam_handle, authentication_result));
/* Report authentication result */
write_string (username);
gboolean auth_complete = TRUE;
write_data (&auth_complete, sizeof (auth_complete));
write_data (&authentication_result, sizeof (authentication_result));
write_string (authentication_result_string);
/* Check we got a valid user */
if (!username)
{
g_printerr ("No user selected during authentication\n");
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
/* Stop if we didn't authenticated */
if (authentication_result != PAM_SUCCESS)
{
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
/* Get the command to run (blocks) */
g_autofree gchar *log_filename = read_string ();
LogMode log_mode = LOG_MODE_BACKUP_AND_TRUNCATE;
if (version >= 3)
read_data (&log_mode, sizeof (log_mode));
if (version >= 1)
{
g_free (tty);
tty = read_string ();
}
g_autofree gchar *x_authority_filename = read_string ();
if (version >= 1)
{
g_free (xdisplay);
xdisplay = read_string ();
g_clear_object (&x_authority);
x_authority = read_xauth ();
}
gsize env_length;
read_data (&env_length, sizeof (env_length));
for (int i = 0; i < env_length; i++)
pam_putenv (pam_handle, read_string ());
gsize command_argc;
read_data (&command_argc, sizeof (command_argc));
g_auto(GStrv) command_argv = g_malloc (sizeof (gchar *) * (command_argc + 1));
int i;
for (i = 0; i < command_argc; i++)
command_argv[i] = read_string ();
command_argv[i] = NULL;
/* If nothing to run just refresh credentials because we successfully authenticated */
if (command_argc == 0)
{
pam_setcred (pam_handle, PAM_REINITIALIZE_CRED);
pam_end (pam_handle, 0);
return EXIT_SUCCESS;
}
/* Redirect stderr to a log file */
if (log_filename)
{
if (g_path_is_absolute (log_filename))
{
int fd = log_file_open (log_filename, log_mode);
dup2 (fd, STDERR_FILENO);
close (fd);
g_clear_pointer (&log_filename, g_free);
}
}
else
{
int fd = open ("/dev/null", O_WRONLY);
dup2 (fd, STDERR_FILENO);
close (fd);
}
/* Set group membership - these can be overridden in pam_setcred */
if (getuid () == 0)
{
if (initgroups (username, user_get_gid (user)) < 0)
{
g_printerr ("Failed to initialize supplementary groups for %s: %s\n", username, strerror (errno));
_exit (EXIT_FAILURE);
}
}
/* Set credentials */
result = pam_setcred (pam_handle, PAM_ESTABLISH_CRED);
if (result != PAM_SUCCESS)
{
g_printerr ("Failed to establish PAM credentials: %s\n", pam_strerror (pam_handle, result));
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
/* Open the session */
result = pam_open_session (pam_handle, 0);
if (result != PAM_SUCCESS)
{
g_printerr ("Failed to open PAM session: %s\n", pam_strerror (pam_handle, result));
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
/* Open a connection to the system bus for ConsoleKit - we must keep it open or CK will close the session */
g_autoptr(GError) error = NULL;
g_autoptr(GDBusConnection) bus = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, &error);
if (error)
g_printerr ("Unable to contact system bus: %s", error->message);
if (!bus)
{
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
/* Check what logind session we are, or fallback to ConsoleKit */
const gchar *login1_session_id = pam_getenv (pam_handle, "XDG_SESSION_ID");
g_autofree gchar *console_kit_cookie = NULL;
if (login1_session_id)
{
write_string (login1_session_id);
if (version >= 2)
write_string (NULL);
}
else
{
GVariantBuilder ck_parameters;
g_variant_builder_init (&ck_parameters, G_VARIANT_TYPE ("(a(sv))"));
g_variant_builder_open (&ck_parameters, G_VARIANT_TYPE ("a(sv)"));
g_variant_builder_add (&ck_parameters, "(sv)", "unix-user", g_variant_new_int32 (user_get_uid (user)));
if (g_strcmp0 (pam_getenv (pam_handle, "XDG_SESSION_CLASS"), "greeter") == 0)
g_variant_builder_add (&ck_parameters, "(sv)", "session-type", g_variant_new_string ("LoginWindow"));
if (xdisplay)
{
g_variant_builder_add (&ck_parameters, "(sv)", "x11-display", g_variant_new_string (xdisplay));
if (tty)
g_variant_builder_add (&ck_parameters, "(sv)", "x11-display-device", g_variant_new_string (tty));
}
if (remote_host_name)
{
g_variant_builder_add (&ck_parameters, "(sv)", "is-local", g_variant_new_boolean (FALSE));
g_variant_builder_add (&ck_parameters, "(sv)", "remote-host-name", g_variant_new_string (remote_host_name));
}
else
g_variant_builder_add (&ck_parameters, "(sv)", "is-local", g_variant_new_boolean (TRUE));
console_kit_cookie = ck_open_session (&ck_parameters);
if (version >= 2)
write_string (NULL);
write_string (console_kit_cookie);
if (console_kit_cookie)
{
g_autofree gchar *value = NULL;
g_autofree gchar *runtime_dir = NULL;
value = g_strdup_printf ("XDG_SESSION_COOKIE=%s", console_kit_cookie);
pam_putenv (pam_handle, value);
runtime_dir = ck_get_xdg_runtime_dir (console_kit_cookie);
if (runtime_dir)
{
g_autofree gchar *v = g_strdup_printf ("XDG_RUNTIME_DIR=%s", runtime_dir);
pam_putenv (pam_handle, v);
}
}
}
/* Write X authority */
if (x_authority)
{
gboolean drop_privileges = geteuid () == 0;
if (drop_privileges)
privileges_drop (user_get_uid (user), user_get_gid (user));
g_autoptr(GError) error = NULL;
gboolean result = x_authority_write (x_authority, XAUTH_WRITE_MODE_REPLACE, x_authority_filename, &error);
if (drop_privileges)
privileges_reclaim ();
if (error)
g_printerr ("Error writing X authority: %s\n", error->message);
if (!result)
{
pam_end (pam_handle, 0);
return EXIT_FAILURE;
}
g_autofree gchar *value = g_strdup_printf ("XAUTHORITY=%s", x_authority_filename);
pam_putenv (pam_handle, value);
}
/* Catch terminate signal and pass it to the child */
signal (SIGTERM, signal_cb);
/* Run the command as the authenticated user */
uid_t uid = user_get_uid (user);
gid_t gid = user_get_gid (user);
const gchar *home_directory = user_get_home_directory (user);
child_pid = fork ();
if (child_pid == 0)
{
/* Make this process its own session */
if (setsid () < 0)
_exit (errno);
/* Change to this user */
if (getuid () == 0)
{
if (setgid (gid) != 0)
_exit (errno);
if (setuid (uid) != 0)
_exit (errno);
}
/* Change working directory */
/* NOTE: This must be done after the permissions are changed because NFS filesystems can
* be setup so the local root user accesses the NFS files as 'nobody'. If the home directories
* are not system readable then the chdir can fail */
if (chdir (home_directory) != 0)
_exit (errno);
if (log_filename)
{
int fd = log_file_open (log_filename, log_mode);
if (fd >= 0)
{
dup2 (fd, STDERR_FILENO);
close (fd);
}
}
/* Reset SIGPIPE handler so the child has default behaviour (we disabled it at LightDM start) */
signal (SIGPIPE, SIG_DFL);
/* Run the command */
execve (command_argv[0], command_argv, pam_getenvlist (pam_handle));
_exit (EXIT_FAILURE);
}
/* Bail out if failed to fork */
int return_code = EXIT_SUCCESS;
if (child_pid < 0)
{
g_printerr ("Failed to fork session child process: %s\n", strerror (errno));
return_code = EXIT_FAILURE;
}
/* Wait for the command to complete (blocks) */
if (child_pid > 0)
{
/* Log to utmp */
if (g_strcmp0 (pam_getenv (pam_handle, "XDG_SESSION_CLASS"), "greeter") != 0)
{
struct utmpx ut;
memset (&ut, 0, sizeof (ut));
ut.ut_type = USER_PROCESS;
ut.ut_pid = child_pid;
if (xdisplay)
strncpy (ut.ut_id, xdisplay, sizeof (ut.ut_id));
if (tty && g_str_has_prefix (tty, "/dev/"))
strncpy (ut.ut_line, tty + strlen ("/dev/"), sizeof (ut.ut_line));
strncpy (ut.ut_user, username, sizeof (ut.ut_user));
if (xdisplay)
strncpy (ut.ut_host, xdisplay, sizeof (ut.ut_host));
else if (remote_host_name)
strncpy (ut.ut_host, remote_host_name, sizeof (ut.ut_host));
struct timeval tv;
gettimeofday (&tv, NULL);
ut.ut_tv.tv_sec = tv.tv_sec;
ut.ut_tv.tv_usec = tv.tv_usec;
/* Write records to utmp/wtmp databases */
setutxent ();
if (!pututxline (&ut))
g_printerr ("Failed to write utmpx: %s\n", strerror (errno));
endutxent ();
updwtmpx ("/var/log/wtmp", &ut);
#if HAVE_LIBAUDIT
audit_event (AUDIT_USER_LOGIN, username, uid, remote_host_name, tty, TRUE);
#endif
}
int child_status;
waitpid (child_pid, &child_status, 0);
child_pid = 0;
if (WIFEXITED (child_status))
return_code = WEXITSTATUS (child_status);
else
return_code = EXIT_FAILURE;
/* Log to utmp */
if (g_strcmp0 (pam_getenv (pam_handle, "XDG_SESSION_CLASS"), "greeter") != 0)
{
struct utmpx ut;
memset (&ut, 0, sizeof (ut));
ut.ut_type = DEAD_PROCESS;
ut.ut_pid = child_pid;
if (xdisplay)
strncpy (ut.ut_id, xdisplay, sizeof (ut.ut_id));
if (tty && g_str_has_prefix (tty, "/dev/"))
strncpy (ut.ut_line, tty + strlen ("/dev/"), sizeof (ut.ut_line));
strncpy (ut.ut_user, username, sizeof (ut.ut_user));
if (xdisplay)
strncpy (ut.ut_host, xdisplay, sizeof (ut.ut_host));
else if (remote_host_name)
strncpy (ut.ut_host, remote_host_name, sizeof (ut.ut_host));
struct timeval tv;
gettimeofday (&tv, NULL);
ut.ut_tv.tv_sec = tv.tv_sec;
ut.ut_tv.tv_usec = tv.tv_usec;
/* Write records to utmp/wtmp databases */
setutxent ();
if (!pututxline (&ut))
g_printerr ("Failed to write utmpx: %s\n", strerror (errno));
endutxent ();
updwtmpx ("/var/log/wtmp", &ut);
#if HAVE_LIBAUDIT
audit_event (AUDIT_USER_LOGOUT, username, uid, remote_host_name, tty, TRUE);
#endif
}
}
/* Remove X authority */
if (x_authority)
{
gboolean drop_privileges = geteuid () == 0;
if (drop_privileges)
privileges_drop (user_get_uid (user), user_get_gid (user));
g_autoptr(GError) error = NULL;
x_authority_write (x_authority, XAUTH_WRITE_MODE_REMOVE, x_authority_filename, &error);
if (drop_privileges)
privileges_reclaim ();
if (error)
g_printerr ("Error removing X authority: %s\n", error->message);
g_clear_error (&error);
/* Ignore this error, don't exit, continue closing the session. */
}
/* Close the Console Kit session */
if (console_kit_cookie)
ck_close_session (console_kit_cookie);
/* Close the session */
pam_close_session (pam_handle, 0);
/* Remove credentials */
pam_setcred (pam_handle, PAM_DELETE_CRED);
pam_end (pam_handle, 0);
pam_handle = NULL;
/* Return result of session process to the daemon */
return return_code;
}
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