vtoyfat/vtoyfat_linux.c

   1 /******************************************************************************
   2  * vtoyfat.c  ---- Parse fat file system
   3  *
   4  * Copyright (c) 2020, longpanda <admin@ventoy.net>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 3 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <errno.h>
  25 #include <sys/stat.h>
  26 #include <fcntl.h>
  27
  28 #include <fat_filelib.h>
  29
  30 static int g_disk_fd = 0;
  31
  32 static int vtoy_disk_read(uint32 sector, uint8 *buffer, uint32 sector_count)
  33 {
  34     lseek(g_disk_fd, sector * 512, SEEK_SET);
  35     read(g_disk_fd, buffer, sector_count * 512);
  36
  37     return 1;
  38 }
  39
  40 static int check_secure_boot(void)
  41 {
  42     void *flfile = NULL;
  43
  44     flfile = fl_fopen("/EFI/BOOT/grubx64_real.efi", "rb");
  45     if (flfile)
  46     {
  47         fl_fclose(flfile);
  48         return 0;
  49     }
  50
  51     return 1;
  52 }
  53
  54 static int get_ventoy_version(void)
  55 {
  56     int rc = 1;
  57     int size = 0;
  58     char *buf = NULL;
  59     char *pos = NULL;
  60     char *end = NULL;
  61     void *flfile = NULL;
  62
  63     flfile = fl_fopen("/grub/grub.cfg", "rb");
  64     if (flfile)
  65     {
  66         fl_fseek(flfile, 0, SEEK_END);
  67         size = (int)fl_ftell(flfile);
  68
  69         fl_fseek(flfile, 0, SEEK_SET);
  70
  71         buf = malloc(size + 1);
  72         if (buf)
  73         {
  74             fl_fread(buf, 1, size, flfile);
  75             buf[size] = 0;
  76
  77             pos = strstr(buf, "VENTOY_VERSION=");
  78             if (pos)
  79             {
  80                 pos += strlen("VENTOY_VERSION=");
  81                 if (*pos == '"')
  82                 {
  83                     pos++;
  84                 }
  85
  86                 end = pos;
  87                 while (*end != 0 && *end != '"' && *end != '\r' && *end != '\n')
  88                 {
  89                     end++;
  90                 }
  91
  92                 *end = 0;
  93
  94                 printf("%s\n", pos);
  95                 rc = 0;
  96             }
  97             free(buf);
  98         }
  99
 100         fl_fclose(flfile);
 101     }
 102
 103     return rc;
 104 }
 105
 106 int main(int argc, char **argv)
 107 {
 108     int op = 0;
 109     int rc = 1;
 110     char *disk;
 111
 112     if (argc != 2 && argc != 3)
 113     {
 114         printf("Usage: vtoyfat /dev/sdbs \n");
 115         printf("Usage: vtoyfat -s /dev/sdbs \n");
 116         return 1;
 117     }
 118
 119     if (argv[1][0] == '-' && argv[1][1] == 'T')
 120     {
 121         return 0;
 122     }
 123
 124     disk = argv[1];
 125     if (argv[1][0] == '-' && argv[1][1] == 's')
 126     {
 127         op = 1;
 128         disk = argv[2];
 129     }
 130
 131     g_disk_fd = open(disk, O_RDONLY);
 132     if (g_disk_fd < 0)
 133     {
 134         printf("Failed to open %s\n", disk);
 135         return 1;
 136     }
 137
 138     fl_init();
 139
 140     if (0 == fl_attach_media(vtoy_disk_read, NULL))
 141     {
 142         if (op == 0)
 143         {
 144             rc = get_ventoy_version();
 145         }
 146         else
 147         {
 148             rc = check_secure_boot();
 149         }
 150     }
 151
 152     fl_shutdown();
 153
 154     close(g_disk_fd);
 155
 156     return rc;
 157 }
 158