src/efi-boot-generator/efi-boot-generator.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /***
   4   This file is part of systemd.
   5
   6   Copyright 2013 Lennart Poettering
   7
   8   systemd is free software; you can redistribute it and/or modify it
   9   under the terms of the GNU Lesser General Public License as published by
  10   the Free Software Foundation; either version 2.1 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   Lesser General Public License for more details.
  17
  18   You should have received a copy of the GNU Lesser General Public License
  19   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  20 ***/
  21
  22 #include <unistd.h>
  23 #include <stdlib.h>
  24
  25 #include "efivars.h"
  26 #include "path-util.h"
  27 #include "util.h"
  28 #include "mkdir.h"
  29 #include "unit-name.h"
  30 #include "virt.h"
  31 #include "generator.h"
  32 #include "special.h"
  33
  34 static const char *arg_dest = "/tmp";
  35
  36 int main(int argc, char *argv[]) {
  37         _cleanup_free_ char *what = NULL;
  38         _cleanup_fclose_ FILE *f = NULL;
  39         int r = EXIT_SUCCESS;
  40         sd_id128_t id;
  41         char *name;
  42
  43         if (argc > 1 && argc != 4) {
  44                 log_error("This program takes three or no arguments.");
  45                 return EXIT_FAILURE;
  46         }
  47
  48         if (argc > 1)
  49                 arg_dest = argv[3];
  50
  51         log_set_target(LOG_TARGET_SAFE);
  52         log_parse_environment();
  53         log_open();
  54
  55         umask(0022);
  56
  57         if (in_initrd()) {
  58                 log_debug("In initrd, exiting.");
  59                 return EXIT_SUCCESS;
  60         }
  61
  62         if (detect_container(NULL) > 0) {
  63                 log_debug("In a container, exiting.");
  64                 return EXIT_SUCCESS;
  65         }
  66
  67         if (!is_efi_boot()) {
  68                 log_debug("Not an EFI boot, exiting.");
  69                 return EXIT_SUCCESS;
  70         }
  71
  72         if (path_is_mount_point("/boot", true) <= 0 &&
  73             dir_is_empty("/boot") <= 0) {
  74                 log_debug("/boot already populated, exiting.");
  75                 return EXIT_SUCCESS;
  76         }
  77
  78         r = efi_loader_get_device_part_uuid(&id);
  79         if (r == -ENOENT) {
  80                 log_debug("EFI loader partition unknown, exiting.");
  81                 return EXIT_SUCCESS;
  82         } else if (r < 0) {
  83                 log_error_errno(r, "Failed to read ESP partition UUID: %m");
  84                 return EXIT_FAILURE;
  85         }
  86
  87         name = strappenda(arg_dest, "/boot.mount");
  88         f = fopen(name, "wxe");
  89         if (!f) {
  90                 log_error_errno(errno, "Failed to create mount unit file %s: %m", name);
  91                 return EXIT_FAILURE;
  92         }
  93
  94         r = asprintf(&what,
  95                      "/dev/disk/by-partuuid/%02x%02x%02x%02x-%02x%02x-%02x%02x-%02x%02x-%02x%02x%02x%02x%02x%02x",
  96                      SD_ID128_FORMAT_VAL(id));
  97         if (r < 0) {
  98                 log_oom();
  99                 return EXIT_FAILURE;
 100         }
 101
 102         fprintf(f,
 103                 "# Automatially generated by systemd-efi-boot-generator\n\n"
 104                 "[Unit]\n"
 105                 "Description=EFI System Partition\n"
 106                 "Documentation=man:systemd-efi-boot-generator(8)\n");
 107
 108         r = generator_write_fsck_deps(f, arg_dest, what, "/boot", "vfat");
 109         if (r < 0)
 110                 return EXIT_FAILURE;
 111
 112         fprintf(f,
 113                 "\n"
 114                 "[Mount]\n"
 115                 "What=%s\n"
 116                 "Where=/boot\n"
 117                 "Type=vfat\n"
 118                 "Options=umask=0077,noauto\n",
 119                 what);
 120
 121         fflush(f);
 122         if (ferror(f)) {
 123                 log_error_errno(errno, "Failed to write mount unit file: %m");
 124                 return EXIT_FAILURE;
 125         }
 126
 127         name = strappenda(arg_dest, "/boot.automount");
 128         fclose(f);
 129         f = fopen(name, "wxe");
 130         if (!f) {
 131                 log_error_errno(errno, "Failed to create automount unit file %s: %m", name);
 132                 return EXIT_FAILURE;
 133         }
 134
 135         fputs("# Automatially generated by systemd-efi-boot-generator\n\n"
 136               "[Unit]\n"
 137               "Description=EFI System Partition Automount\n\n"
 138               "[Automount]\n"
 139               "Where=/boot\n", f);
 140
 141         fflush(f);
 142         if (ferror(f)) {
 143                 log_error_errno(errno, "Failed to write automount unit file: %m");
 144                 return EXIT_FAILURE;
 145         }
 146
 147         name = strappenda(arg_dest, "/" SPECIAL_LOCAL_FS_TARGET ".wants/boot.automount");
 148         mkdir_parents(name, 0755);
 149
 150         if (symlink("../boot.automount", name) < 0) {
 151                 log_error_errno(errno, "Failed to create symlink %s: %m", name);
 152                 return EXIT_FAILURE;
 153         }
 154
 155         return EXIT_SUCCESS;
 156 }