src/core/selinux-setup.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2010 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 <unistd.h>
  23 #include <stdio.h>
  24 #include <errno.h>
  25 #include <string.h>
  26 #include <stdlib.h>
  27
  28 #ifdef HAVE_SELINUX
  29 #include <selinux/selinux.h>
  30 #endif
  31
  32 #include "selinux-setup.h"
  33 #include "mount-setup.h"
  34 #include "macro.h"
  35 #include "util.h"
  36 #include "log.h"
  37 #include "label.h"
  38
  39 int selinux_setup(bool *loaded_policy) {
  40
  41 #ifdef HAVE_SELINUX
  42        int enforce = 0;
  43        usec_t before_load, after_load;
  44        security_context_t con;
  45        int r;
  46
  47        assert(loaded_policy);
  48
  49        /* Make sure getcon() works, which needs /proc and /sys */
  50        mount_setup_early();
  51
  52        /* Already initialized by somebody else? */
  53        r = getcon_raw(&con);
  54        if (r == 0) {
  55                bool initialized;
  56
  57                initialized = !streq(con, "kernel");
  58                freecon(con);
  59
  60                if (initialized)
  61                        return 0;
  62        }
  63
  64        /* Make sure we have no fds open while loading the policy and
  65         * transitioning */
  66        log_close();
  67
  68        /* Now load the policy */
  69        before_load = now(CLOCK_MONOTONIC);
  70        r = selinux_init_load_policy(&enforce);
  71
  72        if (r == 0) {
  73                char timespan[FORMAT_TIMESPAN_MAX];
  74                char *label;
  75
  76                label_retest_selinux();
  77
  78                /* Transition to the new context */
  79                r = label_get_create_label_from_exe(SYSTEMD_BINARY_PATH, &label);
  80                if (r < 0 || label == NULL) {
  81                        log_open();
  82                        log_error("Failed to compute init label, ignoring.");
  83                } else {
  84                        r = setcon(label);
  85
  86                        log_open();
  87                        if (r < 0)
  88                                log_error("Failed to transition into init label '%s', ignoring.", label);
  89
  90                        label_free(label);
  91                }
  92
  93                after_load = now(CLOCK_MONOTONIC);
  94
  95                log_info("Successfully loaded SELinux policy in %s.",
  96                          format_timespan(timespan, sizeof(timespan), after_load - before_load));
  97
  98                *loaded_policy = true;
  99
 100        } else {
 101                log_open();
 102
 103                if (enforce > 0) {
 104                        log_error("Failed to load SELinux policy. Freezing.");
 105                        return -EIO;
 106                } else
 107                        log_debug("Unable to load SELinux policy. Ignoring.");
 108        }
 109 #endif
 110
 111        return 0;
 112 }