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