cmd/nvedit_efi.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  Integrate UEFI variables to u-boot env interface
   4  *
   5  *  Copyright (c) 2018 AKASHI Takahiro, Linaro Limited
   6  */
   7
   8 #include <charset.h>
   9 #include <common.h>
  10 #include <command.h>
  11 #include <efi_loader.h>
  12 #include <efi_variable.h>
  13 #include <env.h>
  14 #include <exports.h>
  15 #include <hexdump.h>
  16 #include <malloc.h>
  17 #include <mapmem.h>
  18 #include <rtc.h>
  19 #include <uuid.h>
  20 #include <linux/kernel.h>
  21
  22 /*
  23  * From efi_variable.c,
  24  *
  25  * Mapping between UEFI variables and u-boot variables:
  26  *
  27  *   efi_$guid_$varname = {attributes}(type)value
  28  */
  29
  30 static const struct {
  31         u32 mask;
  32         char *text;
  33 } efi_var_attrs[] = {
  34         {EFI_VARIABLE_NON_VOLATILE, "NV"},
  35         {EFI_VARIABLE_BOOTSERVICE_ACCESS, "BS"},
  36         {EFI_VARIABLE_RUNTIME_ACCESS, "RT"},
  37         {EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS, "AW"},
  38         {EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS, "AT"},
  39         {EFI_VARIABLE_READ_ONLY, "RO"},
  40 };
  41
  42 /**
  43  * efi_dump_single_var() - show information about a UEFI variable
  44  *
  45  * @name:       Name of the variable
  46  * @guid:       Vendor GUID
  47  * @verbose:    if true, dump data
  48  *
  49  * Show information encoded in one UEFI variable
  50  */
  51 static void efi_dump_single_var(u16 *name, const efi_guid_t *guid, bool verbose)
  52 {
  53         u32 attributes;
  54         u8 *data;
  55         u64 time;
  56         struct rtc_time tm;
  57         efi_uintn_t size;
  58         int count, i;
  59         efi_status_t ret;
  60
  61         data = NULL;
  62         size = 0;
  63         ret = efi_get_variable_int(name, guid, &attributes, &size, data, &time);
  64         if (ret == EFI_BUFFER_TOO_SMALL) {
  65                 data = malloc(size);
  66                 if (!data)
  67                         goto out;
  68
  69                 ret = efi_get_variable_int(name, guid, &attributes, &size,
  70                                            data, &time);
  71         }
  72         if (ret == EFI_NOT_FOUND) {
  73                 printf("Error: \"%ls\" not defined\n", name);
  74                 goto out;
  75         }
  76         if (ret != EFI_SUCCESS)
  77                 goto out;
  78
  79         rtc_to_tm(time, &tm);
  80         printf("%ls:\n    %pUl (%pUs)\n", name, guid, guid);
  81         if (attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
  82                 printf("    %04d-%02d-%02d %02d:%02d:%02d\n", tm.tm_year,
  83                        tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
  84         printf("    ");
  85         for (count = 0, i = 0; i < ARRAY_SIZE(efi_var_attrs); i++)
  86                 if (attributes & efi_var_attrs[i].mask) {
  87                         if (count)
  88                                 putc('|');
  89                         count++;
  90                         puts(efi_var_attrs[i].text);
  91                 }
  92         printf(", DataSize = 0x%zx\n", size);
  93         if (verbose)
  94                 print_hex_dump("    ", DUMP_PREFIX_OFFSET, 16, 1,
  95                                data, size, true);
  96
  97 out:
  98         free(data);
  99 }
 100
 101 static bool match_name(int argc, char *const argv[], u16 *var_name16)
 102 {
 103         char *buf, *p;
 104         size_t buflen;
 105         int i;
 106         bool result = false;
 107
 108         buflen = utf16_utf8_strlen(var_name16) + 1;
 109         buf = calloc(1, buflen);
 110         if (!buf)
 111                 return result;
 112
 113         p = buf;
 114         utf16_utf8_strcpy(&p, var_name16);
 115
 116         for (i = 0; i < argc; argc--, argv++) {
 117                 if (!strcmp(buf, argv[i])) {
 118                         result = true;
 119                         goto out;
 120                 }
 121         }
 122
 123 out:
 124         free(buf);
 125
 126         return result;
 127 }
 128
 129 /**
 130  * efi_dump_var_all() - show information about all the UEFI variables
 131  *
 132  * @argc:       Number of arguments (variables)
 133  * @argv:       Argument (variable name) array
 134  * @verbose:    if true, dump data
 135  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 136  *
 137  * Show information encoded in all the UEFI variables
 138  */
 139 static int efi_dump_var_all(int argc,  char *const argv[],
 140                             const efi_guid_t *guid_p, bool verbose)
 141 {
 142         u16 *var_name16, *p;
 143         efi_uintn_t buf_size, size;
 144         efi_guid_t guid;
 145         efi_status_t ret;
 146         bool match = false;
 147
 148         buf_size = 128;
 149         var_name16 = malloc(buf_size);
 150         if (!var_name16)
 151                 return CMD_RET_FAILURE;
 152
 153         var_name16[0] = 0;
 154         for (;;) {
 155                 size = buf_size;
 156                 ret = efi_get_next_variable_name_int(&size, var_name16,
 157                                                      &guid);
 158                 if (ret == EFI_NOT_FOUND)
 159                         break;
 160                 if (ret == EFI_BUFFER_TOO_SMALL) {
 161                         buf_size = size;
 162                         p = realloc(var_name16, buf_size);
 163                         if (!p) {
 164                                 free(var_name16);
 165                                 return CMD_RET_FAILURE;
 166                         }
 167                         var_name16 = p;
 168                         ret = efi_get_next_variable_name_int(&size, var_name16,
 169                                                              &guid);
 170                 }
 171                 if (ret != EFI_SUCCESS) {
 172                         free(var_name16);
 173                         return CMD_RET_FAILURE;
 174                 }
 175
 176                 if (guid_p && guidcmp(guid_p, &guid))
 177                         continue;
 178                 if (!argc || match_name(argc, argv, var_name16)) {
 179                         match = true;
 180                         efi_dump_single_var(var_name16, &guid, verbose);
 181                 }
 182         }
 183         free(var_name16);
 184
 185         if (!match && argc == 1) {
 186                 printf("Error: \"%s\" not defined\n", argv[0]);
 187                 return CMD_RET_FAILURE;
 188         }
 189
 190         return CMD_RET_SUCCESS;
 191 }
 192
 193 /**
 194  * do_env_print_efi() - show information about UEFI variables
 195  *
 196  * @cmdtp:      Command table
 197  * @flag:       Command flag
 198  * @argc:       Number of arguments
 199  * @argv:       Argument array
 200  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 201  *
 202  * This function is for "env print -e" or "printenv -e" command:
 203  *   => env print -e [-n] [-guid <guid> | -all] [var [...]]
 204  * If one or more variable names are specified, show information
 205  * named UEFI variables, otherwise show all the UEFI variables.
 206  */
 207 int do_env_print_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 208                      char *const argv[])
 209 {
 210         const efi_guid_t *guid_p = NULL;
 211         efi_guid_t guid;
 212         bool verbose = true;
 213         efi_status_t ret;
 214
 215         /* Initialize EFI drivers */
 216         ret = efi_init_obj_list();
 217         if (ret != EFI_SUCCESS) {
 218                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 219                        ret & ~EFI_ERROR_MASK);
 220                 return CMD_RET_FAILURE;
 221         }
 222
 223         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 224                 if (!strcmp(argv[0], "-guid")) {
 225                         if (argc == 1)
 226                                 return CMD_RET_USAGE;
 227                         argc--;
 228                         argv++;
 229                         if (uuid_str_to_bin(argv[0], guid.b,
 230                                             UUID_STR_FORMAT_GUID))
 231                                 return CMD_RET_USAGE;
 232                         guid_p = (const efi_guid_t *)guid.b;
 233                 } else if (!strcmp(argv[0], "-n")) {
 234                         verbose = false;
 235                 } else {
 236                         return CMD_RET_USAGE;
 237                 }
 238         }
 239
 240         /* enumerate and show all UEFI variables */
 241         return efi_dump_var_all(argc, argv, guid_p, verbose);
 242 }
 243
 244 /**
 245  * append_value() - encode UEFI variable's value
 246  * @bufp:       Buffer of encoded UEFI variable's value
 247  * @sizep:      Size of buffer
 248  * @data:       data to be encoded into the value
 249  * Return:      0 on success, -1 otherwise
 250  *
 251  * Interpret a given data string and append it to buffer.
 252  * Buffer will be realloc'ed if necessary.
 253  *
 254  * Currently supported formats are:
 255  *   =0x0123...:                Hexadecimal number
 256  *   =H0123...:                 Hexadecimal-byte array
 257  *   ="...", =S"..." or <string>:
 258  *                              String
 259  */
 260 static int append_value(char **bufp, size_t *sizep, char *data)
 261 {
 262         char *tmp_buf = NULL, *new_buf = NULL, *value;
 263         unsigned long len = 0;
 264
 265         if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */
 266                 union {
 267                         u8 u8;
 268                         u16 u16;
 269                         u32 u32;
 270                         u64 u64;
 271                 } tmp_data;
 272                 unsigned long hex_value;
 273                 void *hex_ptr;
 274
 275                 data += 3;
 276                 len = strlen(data);
 277                 if ((len & 0x1)) /* not multiple of two */
 278                         return -1;
 279
 280                 len /= 2;
 281                 if (len > 8)
 282                         return -1;
 283                 else if (len > 4)
 284                         len = 8;
 285                 else if (len > 2)
 286                         len = 4;
 287
 288                 /* convert hex hexadecimal number */
 289                 if (strict_strtoul(data, 16, &hex_value) < 0)
 290                         return -1;
 291
 292                 tmp_buf = malloc(len);
 293                 if (!tmp_buf)
 294                         return -1;
 295
 296                 if (len == 1) {
 297                         tmp_data.u8 = hex_value;
 298                         hex_ptr = &tmp_data.u8;
 299                 } else if (len == 2) {
 300                         tmp_data.u16 = hex_value;
 301                         hex_ptr = &tmp_data.u16;
 302                 } else if (len == 4) {
 303                         tmp_data.u32 = hex_value;
 304                         hex_ptr = &tmp_data.u32;
 305                 } else {
 306                         tmp_data.u64 = hex_value;
 307                         hex_ptr = &tmp_data.u64;
 308                 }
 309                 memcpy(tmp_buf, hex_ptr, len);
 310                 value = tmp_buf;
 311
 312         } else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */
 313                 data += 2;
 314                 len = strlen(data);
 315                 if (len & 0x1) /* not multiple of two */
 316                         return -1;
 317
 318                 len /= 2;
 319                 tmp_buf = malloc(len);
 320                 if (!tmp_buf)
 321                         return -1;
 322
 323                 if (hex2bin((u8 *)tmp_buf, data, len) < 0) {
 324                         printf("Error: illegal hexadecimal string\n");
 325                         free(tmp_buf);
 326                         return -1;
 327                 }
 328
 329                 value = tmp_buf;
 330         } else { /* string */
 331                 if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) {
 332                         if (data[1] == '"')
 333                                 data += 2;
 334                         else
 335                                 data += 3;
 336                         value = data;
 337                         len = strlen(data) - 1;
 338                         if (data[len] != '"')
 339                                 return -1;
 340                 } else {
 341                         value = data;
 342                         len = strlen(data);
 343                 }
 344         }
 345
 346         new_buf = realloc(*bufp, *sizep + len);
 347         if (!new_buf)
 348                 goto out;
 349
 350         memcpy(new_buf + *sizep, value, len);
 351         *bufp = new_buf;
 352         *sizep += len;
 353
 354 out:
 355         free(tmp_buf);
 356
 357         return 0;
 358 }
 359
 360 /**
 361  * do_env_set_efi() - set UEFI variable
 362  *
 363  * @cmdtp:      Command table
 364  * @flag:       Command flag
 365  * @argc:       Number of arguments
 366  * @argv:       Argument array
 367  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 368  *
 369  * This function is for "env set -e" or "setenv -e" command:
 370  *   => env set -e [-guid guid][-nv][-bs][-rt][-at][-a][-v]
 371  *                 [-i address,size] var, or
 372  *                 var [value ...]
 373  * Encode values specified and set given UEFI variable.
 374  * If no value is specified, delete the variable.
 375  */
 376 int do_env_set_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 377                    char *const argv[])
 378 {
 379         char *var_name, *value, *ep;
 380         ulong addr;
 381         efi_uintn_t size;
 382         efi_guid_t guid;
 383         u32 attributes;
 384         bool default_guid, verbose, value_on_memory;
 385         u16 *var_name16;
 386         efi_status_t ret;
 387
 388         if (argc == 1)
 389                 return CMD_RET_USAGE;
 390
 391         /* Initialize EFI drivers */
 392         ret = efi_init_obj_list();
 393         if (ret != EFI_SUCCESS) {
 394                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 395                        ret & ~EFI_ERROR_MASK);
 396                 return CMD_RET_FAILURE;
 397         }
 398
 399         /*
 400          * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
 401          *           EFI_VARIABLE_RUNTIME_ACCESS;
 402          */
 403         value = NULL;
 404         size = 0;
 405         attributes = 0;
 406         guid = efi_global_variable_guid;
 407         default_guid = true;
 408         verbose = false;
 409         value_on_memory = false;
 410         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 411                 if (!strcmp(argv[0], "-guid")) {
 412                         if (argc == 1)
 413                                 return CMD_RET_USAGE;
 414
 415                         argc--;
 416                         argv++;
 417                         if (uuid_str_to_bin(argv[0], guid.b,
 418                                             UUID_STR_FORMAT_GUID)) {
 419                                 return CMD_RET_USAGE;
 420                         }
 421                         default_guid = false;
 422                 } else if (!strcmp(argv[0], "-bs")) {
 423                         attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
 424                 } else if (!strcmp(argv[0], "-rt")) {
 425                         attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
 426                 } else if (!strcmp(argv[0], "-nv")) {
 427                         attributes |= EFI_VARIABLE_NON_VOLATILE;
 428                 } else if (!strcmp(argv[0], "-at")) {
 429                         attributes |=
 430                           EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
 431                 } else if (!strcmp(argv[0], "-a")) {
 432                         attributes |= EFI_VARIABLE_APPEND_WRITE;
 433                 } else if (!strcmp(argv[0], "-i")) {
 434                         /* data comes from memory */
 435                         if (argc == 1)
 436                                 return CMD_RET_USAGE;
 437
 438                         argc--;
 439                         argv++;
 440                         addr = hextoul(argv[0], &ep);
 441                         if (*ep != ':')
 442                                 return CMD_RET_USAGE;
 443
 444                         /* 0 should be allowed for delete */
 445                         size = hextoul(++ep, NULL);
 446
 447                         value_on_memory = true;
 448                 } else if (!strcmp(argv[0], "-v")) {
 449                         verbose = true;
 450                 } else {
 451                         return CMD_RET_USAGE;
 452                 }
 453         }
 454         if (!argc)
 455                 return CMD_RET_USAGE;
 456
 457         var_name = argv[0];
 458         if (default_guid) {
 459                 if (!strcmp(var_name, "db") || !strcmp(var_name, "dbx") ||
 460                     !strcmp(var_name, "dbt"))
 461                         guid = efi_guid_image_security_database;
 462                 else
 463                         guid = efi_global_variable_guid;
 464         }
 465
 466         if (verbose) {
 467                 printf("GUID: %pUl (%pUs)\n", &guid, &guid);
 468                 printf("Attributes: 0x%x\n", attributes);
 469         }
 470
 471         /* for value */
 472         if (value_on_memory)
 473                 value = map_sysmem(addr, 0);
 474         else if (argc > 1)
 475                 for (argc--, argv++; argc > 0; argc--, argv++)
 476                         if (append_value(&value, &size, argv[0]) < 0) {
 477                                 printf("## Failed to process an argument, %s\n",
 478                                        argv[0]);
 479                                 ret = CMD_RET_FAILURE;
 480                                 goto out;
 481                         }
 482
 483         if (size && verbose) {
 484                 printf("Value:\n");
 485                 print_hex_dump("    ", DUMP_PREFIX_OFFSET,
 486                                16, 1, value, size, true);
 487         }
 488
 489         var_name16 = efi_convert_string(var_name);
 490         if (!var_name16) {
 491                 printf("## Out of memory\n");
 492                 ret = CMD_RET_FAILURE;
 493                 goto out;
 494         }
 495         ret = efi_set_variable_int(var_name16, &guid, attributes, size, value,
 496                                    true);
 497         free(var_name16);
 498         unmap_sysmem(value);
 499         if (ret == EFI_SUCCESS) {
 500                 ret = CMD_RET_SUCCESS;
 501         } else {
 502                 const char *msg;
 503
 504                 switch (ret) {
 505                 case EFI_NOT_FOUND:
 506                         msg = " (not found)";
 507                         break;
 508                 case EFI_WRITE_PROTECTED:
 509                         msg = " (read only)";
 510                         break;
 511                 case EFI_INVALID_PARAMETER:
 512                         msg = " (invalid parameter)";
 513                         break;
 514                 case EFI_SECURITY_VIOLATION:
 515                         msg = " (validation failed)";
 516                         break;
 517                 case EFI_OUT_OF_RESOURCES:
 518                         msg = " (out of memory)";
 519                         break;
 520                 default:
 521                         msg = "";
 522                         break;
 523                 }
 524                 printf("## Failed to set EFI variable%s\n", msg);
 525                 ret = CMD_RET_FAILURE;
 526         }
 527 out:
 528         if (value_on_memory)
 529                 unmap_sysmem(value);
 530         else
 531                 free(value);
 532
 533         return ret;
 534 }