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 static const struct {
  43         efi_guid_t guid;
  44         char *text;
  45 } efi_guid_text[] = {
  46         /* signature database */
  47         {EFI_GLOBAL_VARIABLE_GUID, "EFI_GLOBAL_VARIABLE_GUID"},
  48         {EFI_IMAGE_SECURITY_DATABASE_GUID, "EFI_IMAGE_SECURITY_DATABASE_GUID"},
  49         /* certificate type */
  50         {EFI_CERT_SHA256_GUID, "EFI_CERT_SHA256_GUID"},
  51         {EFI_CERT_X509_GUID, "EFI_CERT_X509_GUID"},
  52         {EFI_CERT_TYPE_PKCS7_GUID, "EFI_CERT_TYPE_PKCS7_GUID"},
  53 };
  54
  55 static const char unknown_guid[] = "";
  56
  57 /**
  58  * efi_guid_to_str() - convert guid to readable name
  59  *
  60  * @guid:       GUID
  61  * Return:      string for GUID
  62  *
  63  * convert guid to readable name
  64  */
  65 static const char *efi_guid_to_str(const efi_guid_t *guid)
  66 {
  67         int i;
  68
  69         for (i = 0; i < ARRAY_SIZE(efi_guid_text); i++)
  70                 if (!guidcmp(guid, &efi_guid_text[i].guid))
  71                         return efi_guid_text[i].text;
  72
  73         return unknown_guid;
  74 }
  75
  76 /**
  77  * efi_dump_single_var() - show information about a UEFI variable
  78  *
  79  * @name:       Name of the variable
  80  * @guid:       Vendor GUID
  81  * @verbose:    if true, dump data
  82  *
  83  * Show information encoded in one UEFI variable
  84  */
  85 static void efi_dump_single_var(u16 *name, const efi_guid_t *guid, bool verbose)
  86 {
  87         u32 attributes;
  88         u8 *data;
  89         u64 time;
  90         struct rtc_time tm;
  91         efi_uintn_t size;
  92         int count, i;
  93         efi_status_t ret;
  94
  95         data = NULL;
  96         size = 0;
  97         ret = efi_get_variable_int(name, guid, &attributes, &size, data, &time);
  98         if (ret == EFI_BUFFER_TOO_SMALL) {
  99                 data = malloc(size);
 100                 if (!data)
 101                         goto out;
 102
 103                 ret = efi_get_variable_int(name, guid, &attributes, &size,
 104                                            data, &time);
 105         }
 106         if (ret == EFI_NOT_FOUND) {
 107                 printf("Error: \"%ls\" not defined\n", name);
 108                 goto out;
 109         }
 110         if (ret != EFI_SUCCESS)
 111                 goto out;
 112
 113         rtc_to_tm(time, &tm);
 114         printf("%ls:\n    %pUl %s\n", name, guid, efi_guid_to_str(guid));
 115         if (attributes & EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
 116                 printf("    %04d-%02d-%02d %02d:%02d:%02d\n", tm.tm_year,
 117                        tm.tm_mon, tm.tm_mday, tm.tm_hour, tm.tm_min, tm.tm_sec);
 118         printf("    ");
 119         for (count = 0, i = 0; i < ARRAY_SIZE(efi_var_attrs); i++)
 120                 if (attributes & efi_var_attrs[i].mask) {
 121                         if (count)
 122                                 putc('|');
 123                         count++;
 124                         puts(efi_var_attrs[i].text);
 125                 }
 126         printf(", DataSize = 0x%zx\n", size);
 127         if (verbose)
 128                 print_hex_dump("    ", DUMP_PREFIX_OFFSET, 16, 1,
 129                                data, size, true);
 130
 131 out:
 132         free(data);
 133 }
 134
 135 static bool match_name(int argc, char *const argv[], u16 *var_name16)
 136 {
 137         char *buf, *p;
 138         size_t buflen;
 139         int i;
 140         bool result = false;
 141
 142         buflen = utf16_utf8_strlen(var_name16) + 1;
 143         buf = calloc(1, buflen);
 144         if (!buf)
 145                 return result;
 146
 147         p = buf;
 148         utf16_utf8_strcpy(&p, var_name16);
 149
 150         for (i = 0; i < argc; argc--, argv++) {
 151                 if (!strcmp(buf, argv[i])) {
 152                         result = true;
 153                         goto out;
 154                 }
 155         }
 156
 157 out:
 158         free(buf);
 159
 160         return result;
 161 }
 162
 163 /**
 164  * efi_dump_var_all() - show information about all the UEFI variables
 165  *
 166  * @argc:       Number of arguments (variables)
 167  * @argv:       Argument (variable name) array
 168  * @verbose:    if true, dump data
 169  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 170  *
 171  * Show information encoded in all the UEFI variables
 172  */
 173 static int efi_dump_var_all(int argc,  char *const argv[],
 174                             const efi_guid_t *guid_p, bool verbose)
 175 {
 176         u16 *var_name16, *p;
 177         efi_uintn_t buf_size, size;
 178         efi_guid_t guid;
 179         efi_status_t ret;
 180         bool match = false;
 181
 182         buf_size = 128;
 183         var_name16 = malloc(buf_size);
 184         if (!var_name16)
 185                 return CMD_RET_FAILURE;
 186
 187         var_name16[0] = 0;
 188         for (;;) {
 189                 size = buf_size;
 190                 ret = EFI_CALL(efi_get_next_variable_name(&size, var_name16,
 191                                                           &guid));
 192                 if (ret == EFI_NOT_FOUND)
 193                         break;
 194                 if (ret == EFI_BUFFER_TOO_SMALL) {
 195                         buf_size = size;
 196                         p = realloc(var_name16, buf_size);
 197                         if (!p) {
 198                                 free(var_name16);
 199                                 return CMD_RET_FAILURE;
 200                         }
 201                         var_name16 = p;
 202                         ret = EFI_CALL(efi_get_next_variable_name(&size,
 203                                                                   var_name16,
 204                                                                   &guid));
 205                 }
 206                 if (ret != EFI_SUCCESS) {
 207                         free(var_name16);
 208                         return CMD_RET_FAILURE;
 209                 }
 210
 211                 if (guid_p && guidcmp(guid_p, &guid))
 212                         continue;
 213                 if (!argc || match_name(argc, argv, var_name16)) {
 214                         match = true;
 215                         efi_dump_single_var(var_name16, &guid, verbose);
 216                 }
 217         }
 218         free(var_name16);
 219
 220         if (!match && argc == 1)
 221                 printf("Error: \"%s\" not defined\n", argv[0]);
 222
 223         return CMD_RET_SUCCESS;
 224 }
 225
 226 /**
 227  * do_env_print_efi() - show information about UEFI variables
 228  *
 229  * @cmdtp:      Command table
 230  * @flag:       Command flag
 231  * @argc:       Number of arguments
 232  * @argv:       Argument array
 233  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 234  *
 235  * This function is for "env print -e" or "printenv -e" command:
 236  *   => env print -e [-n] [-guid <guid> | -all] [var [...]]
 237  * If one or more variable names are specified, show information
 238  * named UEFI variables, otherwise show all the UEFI variables.
 239  */
 240 int do_env_print_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 241                      char *const argv[])
 242 {
 243         const efi_guid_t *guid_p = NULL;
 244         bool verbose = true;
 245         efi_status_t ret;
 246
 247         /* Initialize EFI drivers */
 248         ret = efi_init_obj_list();
 249         if (ret != EFI_SUCCESS) {
 250                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 251                        ret & ~EFI_ERROR_MASK);
 252                 return CMD_RET_FAILURE;
 253         }
 254
 255         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 256                 if (!strcmp(argv[0], "-guid")) {
 257                         efi_guid_t guid;
 258
 259                         if (argc == 1)
 260                                 return CMD_RET_USAGE;
 261                         argc--;
 262                         argv++;
 263                         if (uuid_str_to_bin(argv[0], guid.b,
 264                                             UUID_STR_FORMAT_GUID))
 265                                 return CMD_RET_USAGE;
 266                         guid_p = (const efi_guid_t *)guid.b;
 267                 } else if (!strcmp(argv[0], "-n")) {
 268                         verbose = false;
 269                 } else {
 270                         return CMD_RET_USAGE;
 271                 }
 272         }
 273
 274         /* enumerate and show all UEFI variables */
 275         return efi_dump_var_all(argc, argv, guid_p, verbose);
 276 }
 277
 278 /**
 279  * append_value() - encode UEFI variable's value
 280  * @bufp:       Buffer of encoded UEFI variable's value
 281  * @sizep:      Size of buffer
 282  * @data:       data to be encoded into the value
 283  * Return:      0 on success, -1 otherwise
 284  *
 285  * Interpret a given data string and append it to buffer.
 286  * Buffer will be realloc'ed if necessary.
 287  *
 288  * Currently supported formats are:
 289  *   =0x0123...:                Hexadecimal number
 290  *   =H0123...:                 Hexadecimal-byte array
 291  *   ="...", =S"..." or <string>:
 292  *                              String
 293  */
 294 static int append_value(char **bufp, size_t *sizep, char *data)
 295 {
 296         char *tmp_buf = NULL, *new_buf = NULL, *value;
 297         unsigned long len = 0;
 298
 299         if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */
 300                 union {
 301                         u8 u8;
 302                         u16 u16;
 303                         u32 u32;
 304                         u64 u64;
 305                 } tmp_data;
 306                 unsigned long hex_value;
 307                 void *hex_ptr;
 308
 309                 data += 3;
 310                 len = strlen(data);
 311                 if ((len & 0x1)) /* not multiple of two */
 312                         return -1;
 313
 314                 len /= 2;
 315                 if (len > 8)
 316                         return -1;
 317                 else if (len > 4)
 318                         len = 8;
 319                 else if (len > 2)
 320                         len = 4;
 321
 322                 /* convert hex hexadecimal number */
 323                 if (strict_strtoul(data, 16, &hex_value) < 0)
 324                         return -1;
 325
 326                 tmp_buf = malloc(len);
 327                 if (!tmp_buf)
 328                         return -1;
 329
 330                 if (len == 1) {
 331                         tmp_data.u8 = hex_value;
 332                         hex_ptr = &tmp_data.u8;
 333                 } else if (len == 2) {
 334                         tmp_data.u16 = hex_value;
 335                         hex_ptr = &tmp_data.u16;
 336                 } else if (len == 4) {
 337                         tmp_data.u32 = hex_value;
 338                         hex_ptr = &tmp_data.u32;
 339                 } else {
 340                         tmp_data.u64 = hex_value;
 341                         hex_ptr = &tmp_data.u64;
 342                 }
 343                 memcpy(tmp_buf, hex_ptr, len);
 344                 value = tmp_buf;
 345
 346         } else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */
 347                 data += 2;
 348                 len = strlen(data);
 349                 if (len & 0x1) /* not multiple of two */
 350                         return -1;
 351
 352                 len /= 2;
 353                 tmp_buf = malloc(len);
 354                 if (!tmp_buf)
 355                         return -1;
 356
 357                 if (hex2bin((u8 *)tmp_buf, data, len) < 0) {
 358                         printf("Error: illegal hexadecimal string\n");
 359                         free(tmp_buf);
 360                         return -1;
 361                 }
 362
 363                 value = tmp_buf;
 364         } else { /* string */
 365                 if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) {
 366                         if (data[1] == '"')
 367                                 data += 2;
 368                         else
 369                                 data += 3;
 370                         value = data;
 371                         len = strlen(data) - 1;
 372                         if (data[len] != '"')
 373                                 return -1;
 374                 } else {
 375                         value = data;
 376                         len = strlen(data);
 377                 }
 378         }
 379
 380         new_buf = realloc(*bufp, *sizep + len);
 381         if (!new_buf)
 382                 goto out;
 383
 384         memcpy(new_buf + *sizep, value, len);
 385         *bufp = new_buf;
 386         *sizep += len;
 387
 388 out:
 389         free(tmp_buf);
 390
 391         return 0;
 392 }
 393
 394 /**
 395  * do_env_set_efi() - set UEFI variable
 396  *
 397  * @cmdtp:      Command table
 398  * @flag:       Command flag
 399  * @argc:       Number of arguments
 400  * @argv:       Argument array
 401  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 402  *
 403  * This function is for "env set -e" or "setenv -e" command:
 404  *   => env set -e [-guid guid][-nv][-bs][-rt][-at][-a][-v]
 405  *                 [-i address,size] var, or
 406  *                 var [value ...]
 407  * Encode values specified and set given UEFI variable.
 408  * If no value is specified, delete the variable.
 409  */
 410 int do_env_set_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 411                    char *const argv[])
 412 {
 413         char *var_name, *value, *ep;
 414         ulong addr;
 415         efi_uintn_t size;
 416         efi_guid_t guid;
 417         u32 attributes;
 418         bool default_guid, verbose, value_on_memory;
 419         u16 *var_name16 = NULL, *p;
 420         size_t len;
 421         efi_status_t ret;
 422
 423         if (argc == 1)
 424                 return CMD_RET_USAGE;
 425
 426         /* Initialize EFI drivers */
 427         ret = efi_init_obj_list();
 428         if (ret != EFI_SUCCESS) {
 429                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 430                        ret & ~EFI_ERROR_MASK);
 431                 return CMD_RET_FAILURE;
 432         }
 433
 434         /*
 435          * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
 436          *           EFI_VARIABLE_RUNTIME_ACCESS;
 437          */
 438         value = NULL;
 439         size = 0;
 440         attributes = 0;
 441         guid = efi_global_variable_guid;
 442         default_guid = true;
 443         verbose = false;
 444         value_on_memory = false;
 445         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 446                 if (!strcmp(argv[0], "-guid")) {
 447                         if (argc == 1)
 448                                 return CMD_RET_USAGE;
 449
 450                         argc--;
 451                         argv++;
 452                         if (uuid_str_to_bin(argv[0], guid.b,
 453                                             UUID_STR_FORMAT_GUID)) {
 454                                 return CMD_RET_USAGE;
 455                         }
 456                         default_guid = false;
 457                 } else if (!strcmp(argv[0], "-bs")) {
 458                         attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
 459                 } else if (!strcmp(argv[0], "-rt")) {
 460                         attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
 461                 } else if (!strcmp(argv[0], "-nv")) {
 462                         attributes |= EFI_VARIABLE_NON_VOLATILE;
 463                 } else if (!strcmp(argv[0], "-at")) {
 464                         attributes |=
 465                           EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
 466                 } else if (!strcmp(argv[0], "-a")) {
 467                         attributes |= EFI_VARIABLE_APPEND_WRITE;
 468                 } else if (!strcmp(argv[0], "-i")) {
 469                         /* data comes from memory */
 470                         if (argc == 1)
 471                                 return CMD_RET_USAGE;
 472
 473                         argc--;
 474                         argv++;
 475                         addr = simple_strtoul(argv[0], &ep, 16);
 476                         if (*ep != ':')
 477                                 return CMD_RET_USAGE;
 478
 479                         /* 0 should be allowed for delete */
 480                         size = simple_strtoul(++ep, NULL, 16);
 481
 482                         value_on_memory = true;
 483                 } else if (!strcmp(argv[0], "-v")) {
 484                         verbose = true;
 485                 } else {
 486                         return CMD_RET_USAGE;
 487                 }
 488         }
 489         if (!argc)
 490                 return CMD_RET_USAGE;
 491
 492         var_name = argv[0];
 493         if (default_guid) {
 494                 if (!strcmp(var_name, "db") || !strcmp(var_name, "dbx") ||
 495                     !strcmp(var_name, "dbt"))
 496                         guid = efi_guid_image_security_database;
 497                 else
 498                         guid = efi_global_variable_guid;
 499         }
 500
 501         if (verbose) {
 502                 printf("GUID: %pUl %s\n", &guid,
 503                        efi_guid_to_str((const efi_guid_t *)&guid));
 504                 printf("Attributes: 0x%x\n", attributes);
 505         }
 506
 507         /* for value */
 508         if (value_on_memory)
 509                 value = map_sysmem(addr, 0);
 510         else if (argc > 1)
 511                 for (argc--, argv++; argc > 0; argc--, argv++)
 512                         if (append_value(&value, &size, argv[0]) < 0) {
 513                                 printf("## Failed to process an argument, %s\n",
 514                                        argv[0]);
 515                                 ret = CMD_RET_FAILURE;
 516                                 goto out;
 517                         }
 518
 519         if (size && verbose) {
 520                 printf("Value:\n");
 521                 print_hex_dump("    ", DUMP_PREFIX_OFFSET,
 522                                16, 1, value, size, true);
 523         }
 524
 525         len = utf8_utf16_strnlen(var_name, strlen(var_name));
 526         var_name16 = malloc((len + 1) * 2);
 527         if (!var_name16) {
 528                 printf("## Out of memory\n");
 529                 ret = CMD_RET_FAILURE;
 530                 goto out;
 531         }
 532         p = var_name16;
 533         utf8_utf16_strncpy(&p, var_name, len + 1);
 534
 535         ret = efi_set_variable_int(var_name16, &guid, attributes, size, value,
 536                                    true);
 537         unmap_sysmem(value);
 538         if (ret == EFI_SUCCESS) {
 539                 ret = CMD_RET_SUCCESS;
 540         } else {
 541                 const char *msg;
 542
 543                 switch (ret) {
 544                 case EFI_NOT_FOUND:
 545                         msg = " (not found)";
 546                         break;
 547                 case EFI_WRITE_PROTECTED:
 548                         msg = " (read only)";
 549                         break;
 550                 case EFI_INVALID_PARAMETER:
 551                         msg = " (invalid parameter)";
 552                         break;
 553                 case EFI_SECURITY_VIOLATION:
 554                         msg = " (validation failed)";
 555                         break;
 556                 case EFI_OUT_OF_RESOURCES:
 557                         msg = " (out of memory)";
 558                         break;
 559                 default:
 560                         msg = "";
 561                         break;
 562                 }
 563                 printf("## Failed to set EFI variable%s\n", msg);
 564                 ret = CMD_RET_FAILURE;
 565         }
 566 out:
 567         if (value_on_memory)
 568                 unmap_sysmem(value);
 569         else
 570                 free(value);
 571         free(var_name16);
 572
 573         return ret;
 574 }