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         efi_guid_t guid;
 245         bool verbose = true;
 246         efi_status_t ret;
 247
 248         /* Initialize EFI drivers */
 249         ret = efi_init_obj_list();
 250         if (ret != EFI_SUCCESS) {
 251                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 252                        ret & ~EFI_ERROR_MASK);
 253                 return CMD_RET_FAILURE;
 254         }
 255
 256         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 257                 if (!strcmp(argv[0], "-guid")) {
 258                         if (argc == 1)
 259                                 return CMD_RET_USAGE;
 260                         argc--;
 261                         argv++;
 262                         if (uuid_str_to_bin(argv[0], guid.b,
 263                                             UUID_STR_FORMAT_GUID))
 264                                 return CMD_RET_USAGE;
 265                         guid_p = (const efi_guid_t *)guid.b;
 266                 } else if (!strcmp(argv[0], "-n")) {
 267                         verbose = false;
 268                 } else {
 269                         return CMD_RET_USAGE;
 270                 }
 271         }
 272
 273         /* enumerate and show all UEFI variables */
 274         return efi_dump_var_all(argc, argv, guid_p, verbose);
 275 }
 276
 277 /**
 278  * append_value() - encode UEFI variable's value
 279  * @bufp:       Buffer of encoded UEFI variable's value
 280  * @sizep:      Size of buffer
 281  * @data:       data to be encoded into the value
 282  * Return:      0 on success, -1 otherwise
 283  *
 284  * Interpret a given data string and append it to buffer.
 285  * Buffer will be realloc'ed if necessary.
 286  *
 287  * Currently supported formats are:
 288  *   =0x0123...:                Hexadecimal number
 289  *   =H0123...:                 Hexadecimal-byte array
 290  *   ="...", =S"..." or <string>:
 291  *                              String
 292  */
 293 static int append_value(char **bufp, size_t *sizep, char *data)
 294 {
 295         char *tmp_buf = NULL, *new_buf = NULL, *value;
 296         unsigned long len = 0;
 297
 298         if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */
 299                 union {
 300                         u8 u8;
 301                         u16 u16;
 302                         u32 u32;
 303                         u64 u64;
 304                 } tmp_data;
 305                 unsigned long hex_value;
 306                 void *hex_ptr;
 307
 308                 data += 3;
 309                 len = strlen(data);
 310                 if ((len & 0x1)) /* not multiple of two */
 311                         return -1;
 312
 313                 len /= 2;
 314                 if (len > 8)
 315                         return -1;
 316                 else if (len > 4)
 317                         len = 8;
 318                 else if (len > 2)
 319                         len = 4;
 320
 321                 /* convert hex hexadecimal number */
 322                 if (strict_strtoul(data, 16, &hex_value) < 0)
 323                         return -1;
 324
 325                 tmp_buf = malloc(len);
 326                 if (!tmp_buf)
 327                         return -1;
 328
 329                 if (len == 1) {
 330                         tmp_data.u8 = hex_value;
 331                         hex_ptr = &tmp_data.u8;
 332                 } else if (len == 2) {
 333                         tmp_data.u16 = hex_value;
 334                         hex_ptr = &tmp_data.u16;
 335                 } else if (len == 4) {
 336                         tmp_data.u32 = hex_value;
 337                         hex_ptr = &tmp_data.u32;
 338                 } else {
 339                         tmp_data.u64 = hex_value;
 340                         hex_ptr = &tmp_data.u64;
 341                 }
 342                 memcpy(tmp_buf, hex_ptr, len);
 343                 value = tmp_buf;
 344
 345         } else if (!strncmp(data, "=H", 2)) { /* hexadecimal-byte array */
 346                 data += 2;
 347                 len = strlen(data);
 348                 if (len & 0x1) /* not multiple of two */
 349                         return -1;
 350
 351                 len /= 2;
 352                 tmp_buf = malloc(len);
 353                 if (!tmp_buf)
 354                         return -1;
 355
 356                 if (hex2bin((u8 *)tmp_buf, data, len) < 0) {
 357                         printf("Error: illegal hexadecimal string\n");
 358                         free(tmp_buf);
 359                         return -1;
 360                 }
 361
 362                 value = tmp_buf;
 363         } else { /* string */
 364                 if (!strncmp(data, "=\"", 2) || !strncmp(data, "=S\"", 3)) {
 365                         if (data[1] == '"')
 366                                 data += 2;
 367                         else
 368                                 data += 3;
 369                         value = data;
 370                         len = strlen(data) - 1;
 371                         if (data[len] != '"')
 372                                 return -1;
 373                 } else {
 374                         value = data;
 375                         len = strlen(data);
 376                 }
 377         }
 378
 379         new_buf = realloc(*bufp, *sizep + len);
 380         if (!new_buf)
 381                 goto out;
 382
 383         memcpy(new_buf + *sizep, value, len);
 384         *bufp = new_buf;
 385         *sizep += len;
 386
 387 out:
 388         free(tmp_buf);
 389
 390         return 0;
 391 }
 392
 393 /**
 394  * do_env_set_efi() - set UEFI variable
 395  *
 396  * @cmdtp:      Command table
 397  * @flag:       Command flag
 398  * @argc:       Number of arguments
 399  * @argv:       Argument array
 400  * Return:      CMD_RET_SUCCESS on success, or CMD_RET_RET_FAILURE
 401  *
 402  * This function is for "env set -e" or "setenv -e" command:
 403  *   => env set -e [-guid guid][-nv][-bs][-rt][-at][-a][-v]
 404  *                 [-i address,size] var, or
 405  *                 var [value ...]
 406  * Encode values specified and set given UEFI variable.
 407  * If no value is specified, delete the variable.
 408  */
 409 int do_env_set_efi(struct cmd_tbl *cmdtp, int flag, int argc,
 410                    char *const argv[])
 411 {
 412         char *var_name, *value, *ep;
 413         ulong addr;
 414         efi_uintn_t size;
 415         efi_guid_t guid;
 416         u32 attributes;
 417         bool default_guid, verbose, value_on_memory;
 418         u16 *var_name16 = NULL, *p;
 419         size_t len;
 420         efi_status_t ret;
 421
 422         if (argc == 1)
 423                 return CMD_RET_USAGE;
 424
 425         /* Initialize EFI drivers */
 426         ret = efi_init_obj_list();
 427         if (ret != EFI_SUCCESS) {
 428                 printf("Error: Cannot initialize UEFI sub-system, r = %lu\n",
 429                        ret & ~EFI_ERROR_MASK);
 430                 return CMD_RET_FAILURE;
 431         }
 432
 433         /*
 434          * attributes = EFI_VARIABLE_BOOTSERVICE_ACCESS |
 435          *           EFI_VARIABLE_RUNTIME_ACCESS;
 436          */
 437         value = NULL;
 438         size = 0;
 439         attributes = 0;
 440         guid = efi_global_variable_guid;
 441         default_guid = true;
 442         verbose = false;
 443         value_on_memory = false;
 444         for (argc--, argv++; argc > 0 && argv[0][0] == '-'; argc--, argv++) {
 445                 if (!strcmp(argv[0], "-guid")) {
 446                         if (argc == 1)
 447                                 return CMD_RET_USAGE;
 448
 449                         argc--;
 450                         argv++;
 451                         if (uuid_str_to_bin(argv[0], guid.b,
 452                                             UUID_STR_FORMAT_GUID)) {
 453                                 return CMD_RET_USAGE;
 454                         }
 455                         default_guid = false;
 456                 } else if (!strcmp(argv[0], "-bs")) {
 457                         attributes |= EFI_VARIABLE_BOOTSERVICE_ACCESS;
 458                 } else if (!strcmp(argv[0], "-rt")) {
 459                         attributes |= EFI_VARIABLE_RUNTIME_ACCESS;
 460                 } else if (!strcmp(argv[0], "-nv")) {
 461                         attributes |= EFI_VARIABLE_NON_VOLATILE;
 462                 } else if (!strcmp(argv[0], "-at")) {
 463                         attributes |=
 464                           EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS;
 465                 } else if (!strcmp(argv[0], "-a")) {
 466                         attributes |= EFI_VARIABLE_APPEND_WRITE;
 467                 } else if (!strcmp(argv[0], "-i")) {
 468                         /* data comes from memory */
 469                         if (argc == 1)
 470                                 return CMD_RET_USAGE;
 471
 472                         argc--;
 473                         argv++;
 474                         addr = simple_strtoul(argv[0], &ep, 16);
 475                         if (*ep != ':')
 476                                 return CMD_RET_USAGE;
 477
 478                         /* 0 should be allowed for delete */
 479                         size = simple_strtoul(++ep, NULL, 16);
 480
 481                         value_on_memory = true;
 482                 } else if (!strcmp(argv[0], "-v")) {
 483                         verbose = true;
 484                 } else {
 485                         return CMD_RET_USAGE;
 486                 }
 487         }
 488         if (!argc)
 489                 return CMD_RET_USAGE;
 490
 491         var_name = argv[0];
 492         if (default_guid) {
 493                 if (!strcmp(var_name, "db") || !strcmp(var_name, "dbx") ||
 494                     !strcmp(var_name, "dbt"))
 495                         guid = efi_guid_image_security_database;
 496                 else
 497                         guid = efi_global_variable_guid;
 498         }
 499
 500         if (verbose) {
 501                 printf("GUID: %pUl %s\n", &guid,
 502                        efi_guid_to_str((const efi_guid_t *)&guid));
 503                 printf("Attributes: 0x%x\n", attributes);
 504         }
 505
 506         /* for value */
 507         if (value_on_memory)
 508                 value = map_sysmem(addr, 0);
 509         else if (argc > 1)
 510                 for (argc--, argv++; argc > 0; argc--, argv++)
 511                         if (append_value(&value, &size, argv[0]) < 0) {
 512                                 printf("## Failed to process an argument, %s\n",
 513                                        argv[0]);
 514                                 ret = CMD_RET_FAILURE;
 515                                 goto out;
 516                         }
 517
 518         if (size && verbose) {
 519                 printf("Value:\n");
 520                 print_hex_dump("    ", DUMP_PREFIX_OFFSET,
 521                                16, 1, value, size, true);
 522         }
 523
 524         len = utf8_utf16_strnlen(var_name, strlen(var_name));
 525         var_name16 = malloc((len + 1) * 2);
 526         if (!var_name16) {
 527                 printf("## Out of memory\n");
 528                 ret = CMD_RET_FAILURE;
 529                 goto out;
 530         }
 531         p = var_name16;
 532         utf8_utf16_strncpy(&p, var_name, len + 1);
 533
 534         ret = efi_set_variable_int(var_name16, &guid, attributes, size, value,
 535                                    true);
 536         unmap_sysmem(value);
 537         if (ret == EFI_SUCCESS) {
 538                 ret = CMD_RET_SUCCESS;
 539         } else {
 540                 const char *msg;
 541
 542                 switch (ret) {
 543                 case EFI_NOT_FOUND:
 544                         msg = " (not found)";
 545                         break;
 546                 case EFI_WRITE_PROTECTED:
 547                         msg = " (read only)";
 548                         break;
 549                 case EFI_INVALID_PARAMETER:
 550                         msg = " (invalid parameter)";
 551                         break;
 552                 case EFI_SECURITY_VIOLATION:
 553                         msg = " (validation failed)";
 554                         break;
 555                 case EFI_OUT_OF_RESOURCES:
 556                         msg = " (out of memory)";
 557                         break;
 558                 default:
 559                         msg = "";
 560                         break;
 561                 }
 562                 printf("## Failed to set EFI variable%s\n", msg);
 563                 ret = CMD_RET_FAILURE;
 564         }
 565 out:
 566         if (value_on_memory)
 567                 unmap_sysmem(value);
 568         else
 569                 free(value);
 570         free(var_name16);
 571
 572         return ret;
 573 }