normal/crypto.c

   1 /* crypto.c - support crypto autoload */
   2 /*
   3  *  GRUB  --  GRand Unified Bootloader
   4  *  Copyright (C) 2009  Free Software Foundation, Inc.
   5  *
   6  *  GRUB is free software: you can redistribute it and/or modify
   7  *  it under the terms of the GNU General Public License as published by
   8  *  the Free Software Foundation, either version 3 of the License, or
   9  *  (at your option) any later version.
  10  *
  11  *  GRUB is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with GRUB.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #include <grub/dl.h>
  21 #include <grub/mm.h>
  22 #include <grub/env.h>
  23 #include <grub/misc.h>
  24 #include <grub/crypto.h>
  25 #include <grub/normal.h>
  26
  27 struct load_spec
  28 {
  29   struct load_spec *next;
  30   char *name;
  31   char *modname;
  32 };
  33
  34 struct load_spec *crypto_specs = NULL;
  35
  36 static void
  37 grub_crypto_autoload (const char *name)
  38 {
  39   struct load_spec *cur;
  40   grub_dl_t mod;
  41
  42   for (cur = crypto_specs; cur; cur = cur->next)
  43     if (grub_strcasecmp (name, cur->name) == 0)
  44       {
  45         mod = grub_dl_load (cur->modname);
  46         if (mod)
  47           grub_dl_ref (mod);
  48         grub_errno = GRUB_ERR_NONE;
  49       }
  50 }
  51
  52 static void
  53 grub_crypto_spec_free (void)
  54 {
  55   struct load_spec *cur, *next;
  56   for (cur = crypto_specs; cur; cur = next)
  57     {
  58       next = cur->next;
  59       grub_free (cur->name);
  60       grub_free (cur->modname);
  61       grub_free (cur);
  62     }
  63   crypto_specs = NULL;
  64 }
  65
  66
  67 /* Read the file crypto.lst for auto-loading.  */
  68 void
  69 read_crypto_list (void)
  70 {
  71   const char *prefix;
  72   char *filename;
  73   grub_file_t file;
  74   char *buf = NULL;
  75
  76   prefix = grub_env_get ("prefix");
  77   if (!prefix)
  78     {
  79       grub_errno = GRUB_ERR_NONE;
  80       return;
  81     }
  82
  83   filename = grub_xasprintf ("%s/crypto.lst", prefix);
  84   if (!filename)
  85     {
  86       grub_errno = GRUB_ERR_NONE;
  87       return;
  88     }
  89
  90   file = grub_file_open (filename);
  91   grub_free (filename);
  92   if (!file)
  93     {
  94       grub_errno = GRUB_ERR_NONE;
  95       return;
  96     }
  97
  98   /* Override previous crypto.lst.  */
  99   grub_crypto_spec_free ();
 100
 101   for (;; grub_free (buf))
 102     {
 103       char *p, *name;
 104       struct load_spec *cur;
 105
 106       buf = grub_file_getline (file);
 107
 108       if (! buf)
 109         break;
 110
 111       name = buf;
 112
 113       p = grub_strchr (name, ':');
 114       if (! p)
 115         continue;
 116
 117       *p = '\0';
 118       while (*++p == ' ')
 119         ;
 120
 121       cur = grub_malloc (sizeof (*cur));
 122       if (!cur)
 123         {
 124           grub_errno = GRUB_ERR_NONE;
 125           continue;
 126         }
 127
 128       cur->name = grub_strdup (name);
 129       if (! name)
 130         {
 131           grub_errno = GRUB_ERR_NONE;
 132           grub_free (cur);
 133           continue;
 134         }
 135
 136       cur->modname = grub_strdup (p);
 137       if (! cur->modname)
 138         {
 139           grub_errno = GRUB_ERR_NONE;
 140           grub_free (cur);
 141           grub_free (cur->name);
 142           continue;
 143         }
 144       cur->next = crypto_specs;
 145       crypto_specs = cur;
 146     }
 147
 148   grub_file_close (file);
 149
 150   grub_errno = GRUB_ERR_NONE;
 151
 152   grub_crypto_autoload_hook = grub_crypto_autoload;
 153 }