efiemu/pnvram.c

   1 /* Export pnvram and some variables for runtime */
   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/file.h>
  21 #include <grub/err.h>
  22 #include <grub/normal.h>
  23 #include <grub/mm.h>
  24 #include <grub/misc.h>
  25 #include <grub/efiemu/efiemu.h>
  26 #include <grub/efiemu/runtime.h>
  27 #include <grub/extcmd.h>
  28
  29 /* Place for final location of variables */
  30 static int nvram_handle = 0;
  31 static int nvramsize_handle = 0;
  32 static int high_monotonic_count_handle = 0;
  33 static int timezone_handle = 0;
  34 static int accuracy_handle = 0;
  35 static int daylight_handle = 0;
  36
  37 /* Temporary place */
  38 static grub_uint8_t *nvram;
  39 static grub_size_t nvramsize;
  40 static grub_uint32_t high_monotonic_count;
  41 static grub_int16_t timezone;
  42 static grub_uint8_t daylight;
  43 static grub_uint32_t accuracy;
  44
  45 static const struct grub_arg_option options[] = {
  46   {"size", 's', 0, "number of bytes to reserve for pseudo NVRAM", 0,
  47    ARG_TYPE_INT},
  48   {"high-monotonic-count", 'm', 0,
  49    "Initial value of high monotonic count", 0, ARG_TYPE_INT},
  50   {"timezone", 't', 0,
  51    "Timezone, offset in minutes from GMT", 0, ARG_TYPE_INT},
  52   {"accuracy", 'a', 0,
  53    "Accuracy of clock, in 1e-12 units", 0, ARG_TYPE_INT},
  54   {"daylight", 'd', 0,
  55    "Daylight value, as per EFI specifications", 0, ARG_TYPE_INT},
  56   {0, 0, 0, 0, 0, 0}
  57 };
  58
  59 /* Parse signed value */
  60 static int
  61 grub_strtosl (char *arg, char **end, int base)
  62 {
  63   if (arg[0] == '-')
  64     return -grub_strtoul (arg + 1, end, base);
  65   return grub_strtoul (arg, end, base);
  66 }
  67
  68 /* Export stuff for efiemu */
  69 static grub_err_t
  70 nvram_set (void * data __attribute__ ((unused)))
  71 {
  72   /* Take definitive pointers */
  73   grub_uint8_t *nvram_def = grub_efiemu_mm_obtain_request (nvram_handle);
  74   grub_uint32_t *nvramsize_def
  75     = grub_efiemu_mm_obtain_request (nvramsize_handle);
  76   grub_uint32_t *high_monotonic_count_def
  77     = grub_efiemu_mm_obtain_request (high_monotonic_count_handle);
  78   grub_int16_t *timezone_def
  79     = grub_efiemu_mm_obtain_request (timezone_handle);
  80   grub_uint8_t *daylight_def
  81     = grub_efiemu_mm_obtain_request (daylight_handle);
  82   grub_uint32_t *accuracy_def
  83     = grub_efiemu_mm_obtain_request (accuracy_handle);
  84
  85   /* Copy to definitive loaction */
  86   grub_dprintf ("efiemu", "preparing pnvram\n");
  87   grub_memcpy (nvram_def, nvram, nvramsize);
  88   *nvramsize_def = nvramsize;
  89   *high_monotonic_count_def = high_monotonic_count;
  90   *timezone_def = timezone;
  91   *daylight_def = daylight;
  92   *accuracy_def = accuracy;
  93
  94   /* Register symbols */
  95   grub_efiemu_register_symbol ("efiemu_variables", nvram_handle, 0);
  96   grub_efiemu_register_symbol ("efiemu_varsize", nvramsize_handle, 0);
  97   grub_efiemu_register_symbol ("efiemu_high_monotonic_count",
  98                                high_monotonic_count_handle, 0);
  99   grub_efiemu_register_symbol ("efiemu_time_zone", timezone_handle, 0);
 100   grub_efiemu_register_symbol ("efiemu_time_daylight", daylight_handle, 0);
 101   grub_efiemu_register_symbol ("efiemu_time_accuracy",
 102                                accuracy_handle, 0);
 103
 104   return GRUB_ERR_NONE;
 105 }
 106
 107 static void
 108 nvram_unload (void * data __attribute__ ((unused)))
 109 {
 110   grub_efiemu_mm_return_request (nvram_handle);
 111   grub_efiemu_mm_return_request (nvramsize_handle);
 112   grub_efiemu_mm_return_request (high_monotonic_count_handle);
 113   grub_efiemu_mm_return_request (timezone_handle);
 114   grub_efiemu_mm_return_request (accuracy_handle);
 115   grub_efiemu_mm_return_request (daylight_handle);
 116
 117   grub_free (nvram);
 118   nvram = 0;
 119 }
 120
 121 /* Load the variables file It's in format
 122    guid1:attr1:name1:data1;
 123    guid2:attr2:name2:data2;
 124    ...
 125    Where all fields are in hex
 126 */
 127 static grub_err_t
 128 read_pnvram (char *filename)
 129 {
 130   char *buf, *ptr, *ptr2;
 131   grub_file_t file;
 132   grub_size_t size;
 133   grub_uint8_t *nvramptr = nvram;
 134   struct efi_variable *efivar;
 135   grub_size_t guidlen, datalen;
 136   unsigned i, j;
 137
 138   file = grub_file_open (filename);
 139   if (!file)
 140     return grub_error (GRUB_ERR_BAD_OS, "couldn't read pnvram");
 141   size = grub_file_size (file);
 142   buf = grub_malloc (size + 1);
 143   if (!buf)
 144     return grub_error (GRUB_ERR_OUT_OF_MEMORY, "couldn't read pnvram");
 145   if (grub_file_read (file, buf, size) != (grub_ssize_t) size)
 146     return grub_error (GRUB_ERR_BAD_OS, "couldn't read pnvram");
 147   buf[size] = 0;
 148   grub_file_close (file);
 149
 150   for (ptr = buf; *ptr; )
 151     {
 152       if (grub_isspace (*ptr))
 153         {
 154           ptr++;
 155           continue;
 156         }
 157
 158       efivar = (struct efi_variable *) nvramptr;
 159       if (nvramptr - nvram + sizeof (struct efi_variable) > nvramsize)
 160         return grub_error (GRUB_ERR_OUT_OF_MEMORY,
 161                            "file is too large for reserved variable space");
 162
 163       nvramptr += sizeof (struct efi_variable);
 164
 165       /* look ahow long guid field is*/
 166       guidlen = 0;
 167       for (ptr2 = ptr; (grub_isspace (*ptr2)
 168                         || (*ptr2 >= '0' && *ptr2 <= '9')
 169                         || (*ptr2 >= 'a' && *ptr2 <= 'f')
 170                         || (*ptr2 >= 'A' && *ptr2 <= 'F'));
 171            ptr2++)
 172         if (!grub_isspace (*ptr2))
 173           guidlen++;
 174       guidlen /= 2;
 175
 176       /* Read guid */
 177       if (guidlen != sizeof (efivar->guid))
 178         {
 179           grub_free (buf);
 180           return grub_error (GRUB_ERR_BAD_OS, "can't parse %s", filename);
 181         }
 182       for (i = 0; i < 2 * sizeof (efivar->guid); i++)
 183         {
 184           int hex = 0;
 185           while (grub_isspace (*ptr))
 186             ptr++;
 187           if (*ptr >= '0' && *ptr <= '9')
 188             hex = *ptr - '0';
 189           if (*ptr >= 'a' && *ptr <= 'f')
 190             hex = *ptr - 'a' + 10;
 191           if (*ptr >= 'A' && *ptr <= 'F')
 192             hex = *ptr - 'A' + 10;
 193
 194           if (i%2 == 0)
 195             ((grub_uint8_t *)&(efivar->guid))[i/2] = hex << 4;
 196           else
 197             ((grub_uint8_t *)&(efivar->guid))[i/2] |= hex;
 198           ptr++;
 199         }
 200
 201       while (grub_isspace (*ptr))
 202         ptr++;
 203       if (*ptr != ':')
 204         {
 205           grub_dprintf ("efiemu", "Not colon\n");
 206           grub_free (buf);
 207           return grub_error (GRUB_ERR_BAD_OS, "can't parse %s", filename);
 208         }
 209       ptr++;
 210       while (grub_isspace (*ptr))
 211         ptr++;
 212
 213       /* Attributes can be just parsed by existing functions */
 214       efivar->attributes = grub_strtoul (ptr, &ptr, 16);
 215
 216       while (grub_isspace (*ptr))
 217         ptr++;
 218       if (*ptr != ':')
 219         {
 220           grub_dprintf ("efiemu", "Not colon\n");
 221           grub_free (buf);
 222           return grub_error (GRUB_ERR_BAD_OS, "can't parse %s", filename);
 223         }
 224       ptr++;
 225       while (grub_isspace (*ptr))
 226         ptr++;
 227
 228       /* Read name and value */
 229       for (j = 0; j < 2; j++)
 230         {
 231           /* Look the length */
 232           datalen = 0;
 233           for (ptr2 = ptr; *ptr2 && (grub_isspace (*ptr2)
 234                                      || (*ptr2 >= '0' && *ptr2 <= '9')
 235                                      || (*ptr2 >= 'a' && *ptr2 <= 'f')
 236                                      || (*ptr2 >= 'A' && *ptr2 <= 'F'));
 237                ptr2++)
 238             if (!grub_isspace (*ptr2))
 239               datalen++;
 240           datalen /= 2;
 241
 242           if (nvramptr - nvram + datalen > nvramsize)
 243             {
 244               grub_free (buf);
 245               return grub_error (GRUB_ERR_OUT_OF_MEMORY,
 246                                  "file is too large for reserved "
 247                                  " variable space");
 248             }
 249
 250           for (i = 0; i < 2 * datalen; i++)
 251             {
 252               int hex = 0;
 253               while (grub_isspace (*ptr))
 254                 ptr++;
 255               if (*ptr >= '0' && *ptr <= '9')
 256                 hex = *ptr - '0';
 257               if (*ptr >= 'a' && *ptr <= 'f')
 258                 hex = *ptr - 'a' + 10;
 259               if (*ptr >= 'A' && *ptr <= 'F')
 260                 hex = *ptr - 'A' + 10;
 261
 262               if (i%2 == 0)
 263                 nvramptr[i/2] = hex << 4;
 264               else
 265                 nvramptr[i/2] |= hex;
 266               ptr++;
 267             }
 268           nvramptr += datalen;
 269           while (grub_isspace (*ptr))
 270             ptr++;
 271           if (*ptr != (j ? ';' : ':'))
 272             {
 273               grub_free (buf);
 274               grub_dprintf ("efiemu", j?"Not semicolon\n":"Not colon\n");
 275               return grub_error (GRUB_ERR_BAD_OS, "can't parse %s", filename);
 276             }
 277           if (j)
 278             efivar->size = datalen;
 279           else
 280             efivar->namelen = datalen;
 281
 282           ptr++;
 283         }
 284     }
 285   grub_free (buf);
 286   return GRUB_ERR_NONE;
 287 }
 288
 289 static grub_err_t
 290 grub_efiemu_make_nvram (void)
 291 {
 292   grub_err_t err;
 293
 294   err = grub_efiemu_autocore ();
 295   if (err)
 296     {
 297       grub_free (nvram);
 298       return err;
 299     }
 300
 301   err = grub_efiemu_register_prepare_hook (nvram_set, nvram_unload, 0);
 302   if (err)
 303     {
 304       grub_free (nvram);
 305       return err;
 306     }
 307   nvram_handle
 308     = grub_efiemu_request_memalign (1, nvramsize,
 309                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 310   nvramsize_handle
 311     = grub_efiemu_request_memalign (1, sizeof (grub_uint32_t),
 312                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 313   high_monotonic_count_handle
 314     = grub_efiemu_request_memalign (1, sizeof (grub_uint32_t),
 315                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 316   timezone_handle
 317     = grub_efiemu_request_memalign (1, sizeof (grub_uint16_t),
 318                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 319   daylight_handle
 320     = grub_efiemu_request_memalign (1, sizeof (grub_uint8_t),
 321                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 322   accuracy_handle
 323     = grub_efiemu_request_memalign (1, sizeof (grub_uint32_t),
 324                                     GRUB_EFI_RUNTIME_SERVICES_DATA);
 325
 326   grub_efiemu_request_symbols (6);
 327   return GRUB_ERR_NONE;
 328 }
 329
 330 grub_err_t
 331 grub_efiemu_pnvram (void)
 332 {
 333   if (nvram)
 334     return GRUB_ERR_NONE;
 335
 336   nvramsize = 2048;
 337   high_monotonic_count = 1;
 338   timezone = GRUB_EFI_UNSPECIFIED_TIMEZONE;
 339   accuracy = 50000000;
 340   daylight = 0;
 341
 342   nvram = grub_malloc (nvramsize);
 343   if (!nvram)
 344     return grub_error (GRUB_ERR_OUT_OF_MEMORY,
 345                        "Couldn't allocate space for temporary pnvram storage");
 346   grub_memset (nvram, 0, nvramsize);
 347
 348   return grub_efiemu_make_nvram ();
 349 }
 350
 351 static grub_err_t
 352 grub_cmd_efiemu_pnvram (struct grub_extcmd *cmd,
 353                         int argc, char **args)
 354 {
 355   struct grub_arg_list *state = cmd->state;
 356   grub_err_t err;
 357
 358   if (argc > 1)
 359     return grub_error (GRUB_ERR_BAD_ARGUMENT, "only one argument expected");
 360
 361   nvramsize = state[0].set ? grub_strtoul (state[0].arg, 0, 0) : 2048;
 362   high_monotonic_count = state[1].set ? grub_strtoul (state[1].arg, 0, 0) : 1;
 363   timezone = state[2].set ? grub_strtosl (state[2].arg, 0, 0)
 364     : GRUB_EFI_UNSPECIFIED_TIMEZONE;
 365   accuracy = state[3].set ? grub_strtoul (state[3].arg, 0, 0) : 50000000;
 366   daylight = state[4].set ? grub_strtoul (state[4].arg, 0, 0) : 0;
 367
 368   nvram = grub_malloc (nvramsize);
 369   if (!nvram)
 370     return grub_error (GRUB_ERR_OUT_OF_MEMORY,
 371                        "Couldn't allocate space for temporary pnvram storage");
 372   grub_memset (nvram, 0, nvramsize);
 373
 374   if (argc == 1 && (err = read_pnvram (args[0])))
 375     {
 376       grub_free (nvram);
 377       return err;
 378     }
 379   return grub_efiemu_make_nvram ();
 380 }
 381
 382 static grub_extcmd_t cmd;
 383
 384 void grub_efiemu_pnvram_cmd_register (void);
 385 void grub_efiemu_pnvram_cmd_unregister (void);
 386
 387 void
 388 grub_efiemu_pnvram_cmd_register (void)
 389 {
 390   cmd = grub_register_extcmd ("efiemu_pnvram", grub_cmd_efiemu_pnvram,
 391                               GRUB_COMMAND_FLAG_BOTH,
 392                               "efiemu_pnvram [FILENAME]",
 393                               "Initialise pseudo-NVRAM and load variables "
 394                               "from FILE",
 395                               options);
 396 }
 397
 398 void
 399 grub_efiemu_pnvram_cmd_unregister (void)
 400 {
 401   grub_unregister_extcmd (cmd);
 402 }