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
 188         return CMD_RET_SUCCESS;
 189 }
 190
 191 /**
 192  * do_env_print_efi() - show information about UEFI variables
 193  *
 194  * @cmdtp:      Command table
 195  * @flag:       Command flag
 196  * @argc:       Number of arguments
 197  * @argv:       Argument array
 198  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 199  *
 200  * This function is for "env print -e" or "printenv -e" command:
 201  *   => env print -e [-n] [-guid <guid> | -all] [var [...]]
 202  * If one or more variable names are specified, show information
 203  * named UEFI variables, otherwise show all the UEFI variables.
 204  */
 205 int do_env_print_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 206                      char *const argv[])
 207 {
 208         const efi_guid_t *guid_p = NULL;
 209         efi_guid_t guid;
 210         bool verbose = true;
 211         efi_status_t ret;
 212
 213         /* Initialize EFI drivers */
 214         ret = efi_init_obj_list();
 215         if (ret != EFI_SUCCESS) {
 216                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 217                        ret & ~EFI_ERROR_MASK);
 218                 return CMD_RET_FAILURE;
 219         }
 220
 221         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 222                 if (!strcmp(argv[0], "-guid")) {
 223                         if (argc == 1)
 224                                 return CMD_RET_USAGE;
 225                         argc--;
 226                         argv++;
 227                         if (uuid_str_to_bin(argv[0], guid.b,
 228                                             UUID_STR_FORMAT_GUID))
 229                                 return CMD_RET_USAGE;
 230                         guid_p = (const efi_guid_t *)guid.b;
 231                 } else if (!strcmp(argv[0], "-n")) {
 232                         verbose = false;
 233                 } else {
 234                         return CMD_RET_USAGE;
 235                 }
 236         }
 237
 238         /* enumerate and show all UEFI variables */
 239         return efi_dump_var_all(argc, argv, guid_p, verbose);
 240 }
 241
 242 /**
 243  * append_value() - encode UEFI variable's value
 244  * @bufp:       Buffer of encoded UEFI variable's value
 245  * @sizep:      Size of buffer
 246  * @data:       data to be encoded into the value
 247  * Return:      0 on success, -1 otherwise
 248  *
 249  * Interpret a given data string and append it to buffer.
 250  * Buffer will be realloc'ed if necessary.
 251  *
 252  * Currently supported formats are:
 253  *   =0x0123...:                Hexadecimal number
 254  *   =H0123...:                 Hexadecimal-byte array
 255  *   ="...", =S"..." or <string>:
 256  *                              String
 257  */
 258 static int append_value(char **bufp, size_t *sizep, char *data)
 259 {
 260         char *tmp_buf = NULL, *new_buf = NULL, *value;
 261         unsigned long len = 0;
 262
 263         if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */
 264                 union {
 265                         u8 u8;
 266                         u16 u16;
 267                         u32 u32;
 268                         u64 u64;
 269                 } tmp_data;
 270                 unsigned long hex_value;
 271                 void *hex_ptr;
 272
 273                 data += 3;
 274                 len = strlen(data);
 275                 if ((len & 0x1)) /* not multiple of two */
 276                         return -1;
 277
 278                 len /= 2;
 279                 if (len > 8)
 280                         return -1;
 281                 else if (len > 4)
 282                         len = 8;
 283                 else if (len > 2)
 284                         len = 4;
 285
 286                 /* convert hex hexadecimal number */
 287                 if (strict_strtoul(data, 16, &hex_value) < 0)
 288                         return -1;
 289
 290                 tmp_buf = malloc(len);
 291                 if (!tmp_buf)
 292                         return -1;
 293
 294                 if (len == 1) {
 295                         tmp_data.u8 = hex_value;
 296                         hex_ptr = &tmp_data.u8;
 297                 } else if (len == 2) {
 298                         tmp_data.u16 = hex_value;
 299                         hex_ptr = &tmp_data.u16;
 300                 } else if (len == 4) {
 301                         tmp_data.u32 = hex_value;
 302                         hex_ptr = &tmp_data.u32;
 303                 } else {
 304                         tmp_data.u64 = hex_value;
 305                         hex_ptr = &tmp_data.u64;
 306                 }
 307                 memcpy(tmp_buf, hex_ptr, len);
 308                 value = tmp_buf;
 309
 310         } else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */
 311                 data += 2;
 312                 len = strlen(data);
 313                 if (len & 0x1) /* not multiple of two */
 314                         return -1;
 315
 316                 len /= 2;
 317                 tmp_buf = malloc(len);
 318                 if (!tmp_buf)
 319                         return -1;
 320
 321                 if (hex2bin((u8 *)tmp_buf, data, len) < 0) {
 322                         printf("Error: illegal hexadecimal string\n");
 323                         free(tmp_buf);
 324                         return -1;
 325                 }
 326
 327                 value = tmp_buf;
 328         } else { /* string */
 329                 if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) {
 330                         if (data[1] == '"')
 331                                 data += 2;
 332                         else
 333                                 data += 3;
 334                         value = data;
 335                         len = strlen(data) - 1;
 336                         if (data[len] != '"')
 337                                 return -1;
 338                 } else {
 339                         value = data;
 340                         len = strlen(data);
 341                 }
 342         }
 343
 344         new_buf = realloc(*bufp, *sizep + len);
 345         if (!new_buf)
 346                 goto out;
 347
 348         memcpy(new_buf + *sizep, value, len);
 349         *bufp = new_buf;
 350         *sizep += len;
 351
 352 out:
 353         free(tmp_buf);
 354
 355         return 0;
 356 }
 357
 358 /**
 359  * do_env_set_efi() - set UEFI variable
 360  *
 361  * @cmdtp:      Command table
 362  * @flag:       Command flag
 363  * @argc:       Number of arguments
 364  * @argv:       Argument array
 365  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 366  *
 367  * This function is for "env set -e" or "setenv -e" command:
 368  *   => env set -e [-guid guid][-nv][-bs][-rt][-at][-a][-v]
 369  *                 [-i address,size] var, or
 370  *                 var [value ...]
 371  * Encode values specified and set given UEFI variable.
 372  * If no value is specified, delete the variable.
 373  */
 374 int do_env_set_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 375                    char *const argv[])
 376 {
 377         char *var_name, *value, *ep;
 378         ulong addr;
 379         efi_uintn_t size;
 380         efi_guid_t guid;
 381         u32 attributes;
 382         bool default_guid, verbose, value_on_memory;
 383         u16 *var_name16 = NULL, *p;
 384         size_t len;
 385         efi_status_t ret;
 386
 387         if (argc == 1)
 388                 return CMD_RET_USAGE;
 389
 390         /* Initialize EFI drivers */
 391         ret = efi_init_obj_list();
 392         if (ret != EFI_SUCCESS) {
 393                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 394                        ret & ~EFI_ERROR_MASK);
 395                 return CMD_RET_FAILURE;
 396         }
 397
 398         /*
 399          * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
 400          *           EFI_VARIABLE_RUNTIME_ACCESS;
 401          */
 402         value = NULL;
 403         size = 0;
 404         attributes = 0;
 405         guid = efi_global_variable_guid;
 406         default_guid = true;
 407         verbose = false;
 408         value_on_memory = false;
 409         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 410                 if (!strcmp(argv[0], "-guid")) {
 411                         if (argc == 1)
 412                                 return CMD_RET_USAGE;
 413
 414                         argc--;
 415                         argv++;
 416                         if (uuid_str_to_bin(argv[0], guid.b,
 417                                             UUID_STR_FORMAT_GUID)) {
 418                                 return CMD_RET_USAGE;
 419                         }
 420                         default_guid = false;
 421                 } else if (!strcmp(argv[0], "-bs")) {
 422                         attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
 423                 } else if (!strcmp(argv[0], "-rt")) {
 424                         attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
 425                 } else if (!strcmp(argv[0], "-nv")) {
 426                         attributes |= EFI_VARIABLE_NON_VOLATILE;
 427                 } else if (!strcmp(argv[0], "-at")) {
 428                         attributes |=
 429                           EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
 430                 } else if (!strcmp(argv[0], "-a")) {
 431                         attributes |= EFI_VARIABLE_APPEND_WRITE;
 432                 } else if (!strcmp(argv[0], "-i")) {
 433                         /* data comes from memory */
 434                         if (argc == 1)
 435                                 return CMD_RET_USAGE;
 436
 437                         argc--;
 438                         argv++;
 439                         addr = hextoul(argv[0], &ep);
 440                         if (*ep != ':')
 441                                 return CMD_RET_USAGE;
 442
 443                         /* 0 should be allowed for delete */
 444                         size = hextoul(++ep, NULL);
 445
 446                         value_on_memory = true;
 447                 } else if (!strcmp(argv[0], "-v")) {
 448                         verbose = true;
 449                 } else {
 450                         return CMD_RET_USAGE;
 451                 }
 452         }
 453         if (!argc)
 454                 return CMD_RET_USAGE;
 455
 456         var_name = argv[0];
 457         if (default_guid) {
 458                 if (!strcmp(var_name, "db") || !strcmp(var_name, "dbx") ||
 459                     !strcmp(var_name, "dbt"))
 460                         guid = efi_guid_image_security_database;
 461                 else
 462                         guid = efi_global_variable_guid;
 463         }
 464
 465         if (verbose) {
 466                 printf("GUID: %pUl (%pUs)\n", &guid, &guid);
 467                 printf("Attributes: 0x%x\n", attributes);
 468         }
 469
 470         /* for value */
 471         if (value_on_memory)
 472                 value = map_sysmem(addr, 0);
 473         else if (argc > 1)
 474                 for (argc--, argv++; argc > 0; argc--, argv++)
 475                         if (append_value(&value, &size, argv[0]) < 0) {
 476                                 printf("## Failed to process an argument, %s\n",
 477                                        argv[0]);
 478                                 ret = CMD_RET_FAILURE;
 479                                 goto out;
 480                         }
 481
 482         if (size && verbose) {
 483                 printf("Value:\n");
 484                 print_hex_dump("    ", DUMP_PREFIX_OFFSET,
 485                                16, 1, value, size, true);
 486         }
 487
 488         len = utf8_utf16_strnlen(var_name, strlen(var_name));
 489         var_name16 = malloc((len + 1) * 2);
 490         if (!var_name16) {
 491                 printf("## Out of memory\n");
 492                 ret = CMD_RET_FAILURE;
 493                 goto out;
 494         }
 495         p = var_name16;
 496         utf8_utf16_strncpy(&p, var_name, len + 1);
 497
 498         ret = efi_set_variable_int(var_name16, &guid, attributes, size, value,
 499                                    true);
 500         unmap_sysmem(value);
 501         if (ret == EFI_SUCCESS) {
 502                 ret = CMD_RET_SUCCESS;
 503         } else {
 504                 const char *msg;
 505
 506                 switch (ret) {
 507                 case EFI_NOT_FOUND:
 508                         msg = " (not found)";
 509                         break;
 510                 case EFI_WRITE_PROTECTED:
 511                         msg = " (read only)";
 512                         break;
 513                 case EFI_INVALID_PARAMETER:
 514                         msg = " (invalid parameter)";
 515                         break;
 516                 case EFI_SECURITY_VIOLATION:
 517                         msg = " (validation failed)";
 518                         break;
 519                 case EFI_OUT_OF_RESOURCES:
 520                         msg = " (out of memory)";
 521                         break;
 522                 default:
 523                         msg = "";
 524                         break;
 525                 }
 526                 printf("## Failed to set EFI variable%s\n", msg);
 527                 ret = CMD_RET_FAILURE;
 528         }
 529 out:
 530         if (value_on_memory)
 531                 unmap_sysmem(value);
 532         else
 533                 free(value);
 534         free(var_name16);
 535
 536         return ret;
 537 }