disk/part_efi.c

   1 /*
   2  * Copyright (C) 2008 RuggedCom, Inc.
   3  * Richard Retanubun <RichardRetanubun@RuggedCom.com>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /*
   9  * Problems with CONFIG_SYS_64BIT_LBA:
  10  *
  11  * struct disk_partition.start in include/part.h is sized as ulong.
  12  * When CONFIG_SYS_64BIT_LBA is activated, lbaint_t changes from ulong to uint64_t.
  13  * For now, it is cast back to ulong at assignment.
  14  *
  15  * This limits the maximum size of addressable storage to < 2 Terra Bytes
  16  */
  17 #include <asm/unaligned.h>
  18 #include <common.h>
  19 #include <command.h>
  20 #include <ide.h>
  21 #include <malloc.h>
  22 #include <part_efi.h>
  23 #include <linux/ctype.h>
  24
  25 DECLARE_GLOBAL_DATA_PTR;
  26
  27 #ifdef HAVE_BLOCK_DEVICE
  28 /**
  29  * efi_crc32() - EFI version of crc32 function
  30  * @buf: buffer to calculate crc32 of
  31  * @len - length of buf
  32  *
  33  * Description: Returns EFI-style CRC32 value for @buf
  34  */
  35 static inline u32 efi_crc32(const void *buf, u32 len)
  36 {
  37         return crc32(0, buf, len);
  38 }
  39
  40 /*
  41  * Private function prototypes
  42  */
  43
  44 static int pmbr_part_valid(struct partition *part);
  45 static int is_pmbr_valid(legacy_mbr * mbr);
  46 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
  47                                 gpt_header * pgpt_head, gpt_entry ** pgpt_pte);
  48 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
  49                                 gpt_header * pgpt_head);
  50 static int is_pte_valid(gpt_entry * pte);
  51
  52 static char *print_efiname(gpt_entry *pte)
  53 {
  54         static char name[PARTNAME_SZ + 1];
  55         int i;
  56         for (i = 0; i < PARTNAME_SZ; i++) {
  57                 u8 c;
  58                 c = pte->partition_name[i] & 0xff;
  59                 c = (c && !isprint(c)) ? '.' : c;
  60                 name[i] = c;
  61         }
  62         name[PARTNAME_SZ] = 0;
  63         return name;
  64 }
  65
  66 static efi_guid_t system_guid = PARTITION_SYSTEM_GUID;
  67
  68 static inline int is_bootable(gpt_entry *p)
  69 {
  70         return p->attributes.fields.legacy_bios_bootable ||
  71                 !memcmp(&(p->partition_type_guid), &system_guid,
  72                         sizeof(efi_guid_t));
  73 }
  74
  75 #ifdef CONFIG_EFI_PARTITION
  76 /*
  77  * Public Functions (include/part.h)
  78  */
  79
  80 void print_part_efi(block_dev_desc_t * dev_desc)
  81 {
  82         ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
  83         gpt_entry *gpt_pte = NULL;
  84         int i = 0;
  85         char uuid[37];
  86         unsigned char *uuid_bin;
  87
  88         if (!dev_desc) {
  89                 printf("%s: Invalid Argument(s)\n", __func__);
  90                 return;
  91         }
  92         /* This function validates AND fills in the GPT header and PTE */
  93         if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
  94                          gpt_head, &gpt_pte) != 1) {
  95                 printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
  96                 if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
  97                                  gpt_head, &gpt_pte) != 1) {
  98                         printf("%s: *** ERROR: Invalid Backup GPT ***\n",
  99                                __func__);
 100                         return;
 101                 } else {
 102                         printf("%s: ***        Using Backup GPT ***\n",
 103                                __func__);
 104                 }
 105         }
 106
 107         debug("%s: gpt-entry at %p\n", __func__, gpt_pte);
 108
 109         printf("Part\tStart LBA\tEnd LBA\t\tName\n");
 110         printf("\tAttributes\n");
 111         printf("\tType GUID\n");
 112         printf("\tPartition GUID\n");
 113
 114         for (i = 0; i < le32_to_cpu(gpt_head->num_partition_entries); i++) {
 115                 /* Stop at the first non valid PTE */
 116                 if (!is_pte_valid(&gpt_pte[i]))
 117                         break;
 118
 119                 printf("%3d\t0x%08llx\t0x%08llx\t\"%s\"\n", (i + 1),
 120                         le64_to_cpu(gpt_pte[i].starting_lba),
 121                         le64_to_cpu(gpt_pte[i].ending_lba),
 122                         print_efiname(&gpt_pte[i]));
 123                 printf("\tattrs:\t0x%016llx\n", gpt_pte[i].attributes.raw);
 124                 uuid_bin = (unsigned char *)gpt_pte[i].partition_type_guid.b;
 125                 uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
 126                 printf("\ttype:\t%s\n", uuid);
 127                 uuid_bin = (unsigned char *)gpt_pte[i].unique_partition_guid.b;
 128                 uuid_bin_to_str(uuid_bin, uuid, UUID_STR_FORMAT_GUID);
 129                 printf("\tguid:\t%s\n", uuid);
 130         }
 131
 132         /* Remember to free pte */
 133         free(gpt_pte);
 134         return;
 135 }
 136
 137 int get_partition_info_efi(block_dev_desc_t * dev_desc, int part,
 138                                 disk_partition_t * info)
 139 {
 140         ALLOC_CACHE_ALIGN_BUFFER_PAD(gpt_header, gpt_head, 1, dev_desc->blksz);
 141         gpt_entry *gpt_pte = NULL;
 142
 143         /* "part" argument must be at least 1 */
 144         if (!dev_desc || !info || part < 1) {
 145                 printf("%s: Invalid Argument(s)\n", __func__);
 146                 return -1;
 147         }
 148
 149         /* This function validates AND fills in the GPT header and PTE */
 150         if (is_gpt_valid(dev_desc, GPT_PRIMARY_PARTITION_TABLE_LBA,
 151                         gpt_head, &gpt_pte) != 1) {
 152                 printf("%s: *** ERROR: Invalid GPT ***\n", __func__);
 153                 if (is_gpt_valid(dev_desc, (dev_desc->lba - 1),
 154                                  gpt_head, &gpt_pte) != 1) {
 155                         printf("%s: *** ERROR: Invalid Backup GPT ***\n",
 156                                __func__);
 157                         return -1;
 158                 } else {
 159                         printf("%s: ***        Using Backup GPT ***\n",
 160                                __func__);
 161                 }
 162         }
 163
 164         if (part > le32_to_cpu(gpt_head->num_partition_entries) ||
 165             !is_pte_valid(&gpt_pte[part - 1])) {
 166                 debug("%s: *** ERROR: Invalid partition number %d ***\n",
 167                         __func__, part);
 168                 free(gpt_pte);
 169                 return -1;
 170         }
 171
 172         /* The ulong casting limits the maximum disk size to 2 TB */
 173         info->start = (u64)le64_to_cpu(gpt_pte[part - 1].starting_lba);
 174         /* The ending LBA is inclusive, to calculate size, add 1 to it */
 175         info->size = ((u64)le64_to_cpu(gpt_pte[part - 1].ending_lba) + 1)
 176                      - info->start;
 177         info->blksz = dev_desc->blksz;
 178
 179         sprintf((char *)info->name, "%s",
 180                         print_efiname(&gpt_pte[part - 1]));
 181         sprintf((char *)info->type, "U-Boot");
 182         info->bootable = is_bootable(&gpt_pte[part - 1]);
 183 #ifdef CONFIG_PARTITION_UUIDS
 184         uuid_bin_to_str(gpt_pte[part - 1].unique_partition_guid.b, info->uuid,
 185                         UUID_STR_FORMAT_GUID);
 186 #endif
 187
 188         debug("%s: start 0x" LBAF ", size 0x" LBAF ", name %s", __func__,
 189               info->start, info->size, info->name);
 190
 191         /* Remember to free pte */
 192         free(gpt_pte);
 193         return 0;
 194 }
 195
 196 int test_part_efi(block_dev_desc_t * dev_desc)
 197 {
 198         ALLOC_CACHE_ALIGN_BUFFER_PAD(legacy_mbr, legacymbr, 1, dev_desc->blksz);
 199
 200         /* Read legacy MBR from block 0 and validate it */
 201         if ((dev_desc->block_read(dev_desc->dev, 0, 1, (ulong *)legacymbr) != 1)
 202                 || (is_pmbr_valid(legacymbr) != 1)) {
 203                 return -1;
 204         }
 205         return 0;
 206 }
 207
 208 /**
 209  * set_protective_mbr(): Set the EFI protective MBR
 210  * @param dev_desc - block device descriptor
 211  *
 212  * @return - zero on success, otherwise error
 213  */
 214 static int set_protective_mbr(block_dev_desc_t *dev_desc)
 215 {
 216         /* Setup the Protective MBR */
 217         ALLOC_CACHE_ALIGN_BUFFER(legacy_mbr, p_mbr, 1);
 218         memset(p_mbr, 0, sizeof(*p_mbr));
 219
 220         if (p_mbr == NULL) {
 221                 printf("%s: calloc failed!\n", __func__);
 222                 return -1;
 223         }
 224         /* Append signature */
 225         p_mbr->signature = MSDOS_MBR_SIGNATURE;
 226         p_mbr->partition_record[0].sys_ind = EFI_PMBR_OSTYPE_EFI_GPT;
 227         p_mbr->partition_record[0].start_sect = 1;
 228         p_mbr->partition_record[0].nr_sects = (u32) dev_desc->lba;
 229
 230         /* Write MBR sector to the MMC device */
 231         if (dev_desc->block_write(dev_desc->dev, 0, 1, p_mbr) != 1) {
 232                 printf("** Can't write to device %d **\n",
 233                         dev_desc->dev);
 234                 return -1;
 235         }
 236
 237         return 0;
 238 }
 239
 240 int write_gpt_table(block_dev_desc_t *dev_desc,
 241                 gpt_header *gpt_h, gpt_entry *gpt_e)
 242 {
 243         const int pte_blk_cnt = BLOCK_CNT((gpt_h->num_partition_entries
 244                                            * sizeof(gpt_entry)), dev_desc);
 245         u32 calc_crc32;
 246         u64 val;
 247
 248         debug("max lba: %x\n", (u32) dev_desc->lba);
 249         /* Setup the Protective MBR */
 250         if (set_protective_mbr(dev_desc) < 0)
 251                 goto err;
 252
 253         /* Generate CRC for the Primary GPT Header */
 254         calc_crc32 = efi_crc32((const unsigned char *)gpt_e,
 255                               le32_to_cpu(gpt_h->num_partition_entries) *
 256                               le32_to_cpu(gpt_h->sizeof_partition_entry));
 257         gpt_h->partition_entry_array_crc32 = cpu_to_le32(calc_crc32);
 258
 259         calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
 260                               le32_to_cpu(gpt_h->header_size));
 261         gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
 262
 263         /* Write the First GPT to the block right after the Legacy MBR */
 264         if (dev_desc->block_write(dev_desc->dev, 1, 1, gpt_h) != 1)
 265                 goto err;
 266
 267         if (dev_desc->block_write(dev_desc->dev, 2, pte_blk_cnt, gpt_e)
 268             != pte_blk_cnt)
 269                 goto err;
 270
 271         /* recalculate the values for the Backup GPT Header */
 272         val = le64_to_cpu(gpt_h->my_lba);
 273         gpt_h->my_lba = gpt_h->alternate_lba;
 274         gpt_h->alternate_lba = cpu_to_le64(val);
 275         gpt_h->header_crc32 = 0;
 276
 277         calc_crc32 = efi_crc32((const unsigned char *)gpt_h,
 278                               le32_to_cpu(gpt_h->header_size));
 279         gpt_h->header_crc32 = cpu_to_le32(calc_crc32);
 280
 281         if (dev_desc->block_write(dev_desc->dev,
 282                                   le32_to_cpu(gpt_h->last_usable_lba) + 1,
 283                                   pte_blk_cnt, gpt_e) != pte_blk_cnt)
 284                 goto err;
 285
 286         if (dev_desc->block_write(dev_desc->dev,
 287                                   le32_to_cpu(gpt_h->my_lba), 1, gpt_h) != 1)
 288                 goto err;
 289
 290         debug("GPT successfully written to block device!\n");
 291         return 0;
 292
 293  err:
 294         printf("** Can't write to device %d **\n", dev_desc->dev);
 295         return -1;
 296 }
 297
 298 int gpt_fill_pte(gpt_header *gpt_h, gpt_entry *gpt_e,
 299                 disk_partition_t *partitions, int parts)
 300 {
 301         u32 offset = (u32)le32_to_cpu(gpt_h->first_usable_lba);
 302         ulong start;
 303         u32 last_usable_lba = (u32)le32_to_cpu(gpt_h->last_usable_lba);
 304         int i, k;
 305         size_t efiname_len, dosname_len;
 306 #ifdef CONFIG_PARTITION_UUIDS
 307         char *str_uuid;
 308         unsigned char *bin_uuid;
 309 #endif
 310
 311         for (i = 0; i < parts; i++) {
 312                 /* partition starting lba */
 313                 start = partitions[i].start;
 314                 if (start && (start < offset)) {
 315                         printf("Partition overlap\n");
 316                         return -1;
 317                 }
 318                 if (start) {
 319                         gpt_e[i].starting_lba = cpu_to_le64(start);
 320                         offset = start + partitions[i].size;
 321                 } else {
 322                         gpt_e[i].starting_lba = cpu_to_le64(offset);
 323                         offset += partitions[i].size;
 324                 }
 325                 if (offset >= last_usable_lba) {
 326                         printf("Partitions layout exceds disk size\n");
 327                         return -1;
 328                 }
 329                 /* partition ending lba */
 330                 if ((i == parts - 1) && (partitions[i].size == 0))
 331                         /* extend the last partition to maximuim */
 332                         gpt_e[i].ending_lba = gpt_h->last_usable_lba;
 333                 else
 334                         gpt_e[i].ending_lba = cpu_to_le64(offset - 1);
 335
 336                 /* partition type GUID */
 337                 memcpy(gpt_e[i].partition_type_guid.b,
 338                         &PARTITION_BASIC_DATA_GUID, 16);
 339
 340 #ifdef CONFIG_PARTITION_UUIDS
 341                 str_uuid = partitions[i].uuid;
 342                 bin_uuid = gpt_e[i].unique_partition_guid.b;
 343
 344                 if (uuid_str_to_bin(str_uuid, bin_uuid, UUID_STR_FORMAT_STD)) {
 345                         printf("Partition no. %d: invalid guid: %s\n",
 346                                 i, str_uuid);
 347                         return -1;
 348                 }
 349 #endif
 350
 351                 /* partition attributes */
 352                 memset(&gpt_e[i].attributes, 0,
 353                        sizeof(gpt_entry_attributes));
 354
 355                 /* partition name */
 356                 efiname_len = sizeof(gpt_e[i].partition_name)
 357                         / sizeof(efi_char16_t);
 358                 dosname_len = sizeof(partitions[i].name);
 359
 360                 memset(gpt_e[i].partition_name, 0,
 361                        sizeof(gpt_e[i].partition_name));
 362
 363                 for (k = 0; k < min(dosname_len, efiname_len); k++)
 364                         gpt_e[i].partition_name[k] =
 365                                 (efi_char16_t)(partitions[i].name[k]);
 366
 367                 debug("%s: name: %s offset[%d]: 0x%x size[%d]: 0x" LBAF "\n",
 368                       __func__, partitions[i].name, i,
 369                       offset, i, partitions[i].size);
 370         }
 371
 372         return 0;
 373 }
 374
 375 int gpt_fill_header(block_dev_desc_t *dev_desc, gpt_header *gpt_h,
 376                 char *str_guid, int parts_count)
 377 {
 378         gpt_h->signature = cpu_to_le64(GPT_HEADER_SIGNATURE);
 379         gpt_h->revision = cpu_to_le32(GPT_HEADER_REVISION_V1);
 380         gpt_h->header_size = cpu_to_le32(sizeof(gpt_header));
 381         gpt_h->my_lba = cpu_to_le64(1);
 382         gpt_h->alternate_lba = cpu_to_le64(dev_desc->lba - 1);
 383         gpt_h->first_usable_lba = cpu_to_le64(34);
 384         gpt_h->last_usable_lba = cpu_to_le64(dev_desc->lba - 34);
 385         gpt_h->partition_entry_lba = cpu_to_le64(2);
 386         gpt_h->num_partition_entries = cpu_to_le32(GPT_ENTRY_NUMBERS);
 387         gpt_h->sizeof_partition_entry = cpu_to_le32(sizeof(gpt_entry));
 388         gpt_h->header_crc32 = 0;
 389         gpt_h->partition_entry_array_crc32 = 0;
 390
 391         if (uuid_str_to_bin(str_guid, gpt_h->disk_guid.b, UUID_STR_FORMAT_GUID))
 392                 return -1;
 393
 394         return 0;
 395 }
 396
 397 int gpt_restore(block_dev_desc_t *dev_desc, char *str_disk_guid,
 398                 disk_partition_t *partitions, int parts_count)
 399 {
 400         int ret;
 401
 402         gpt_header *gpt_h = calloc(1, PAD_TO_BLOCKSIZE(sizeof(gpt_header),
 403                                                        dev_desc));
 404         gpt_entry *gpt_e;
 405
 406         if (gpt_h == NULL) {
 407                 printf("%s: calloc failed!\n", __func__);
 408                 return -1;
 409         }
 410
 411         gpt_e = calloc(1, PAD_TO_BLOCKSIZE(GPT_ENTRY_NUMBERS
 412                                                * sizeof(gpt_entry),
 413                                                dev_desc));
 414         if (gpt_e == NULL) {
 415                 printf("%s: calloc failed!\n", __func__);
 416                 free(gpt_h);
 417                 return -1;
 418         }
 419
 420         /* Generate Primary GPT header (LBA1) */
 421         ret = gpt_fill_header(dev_desc, gpt_h, str_disk_guid, parts_count);
 422         if (ret)
 423                 goto err;
 424
 425         /* Generate partition entries */
 426         ret = gpt_fill_pte(gpt_h, gpt_e, partitions, parts_count);
 427         if (ret)
 428                 goto err;
 429
 430         /* Write GPT partition table */
 431         ret = write_gpt_table(dev_desc, gpt_h, gpt_e);
 432
 433 err:
 434         free(gpt_e);
 435         free(gpt_h);
 436         return ret;
 437 }
 438 #endif
 439
 440 /*
 441  * Private functions
 442  */
 443 /*
 444  * pmbr_part_valid(): Check for EFI partition signature
 445  *
 446  * Returns: 1 if EFI GPT partition type is found.
 447  */
 448 static int pmbr_part_valid(struct partition *part)
 449 {
 450         if (part->sys_ind == EFI_PMBR_OSTYPE_EFI_GPT &&
 451                 get_unaligned_le32(&part->start_sect) == 1UL) {
 452                 return 1;
 453         }
 454
 455         return 0;
 456 }
 457
 458 /*
 459  * is_pmbr_valid(): test Protective MBR for validity
 460  *
 461  * Returns: 1 if PMBR is valid, 0 otherwise.
 462  * Validity depends on two things:
 463  *  1) MSDOS signature is in the last two bytes of the MBR
 464  *  2) One partition of type 0xEE is found, checked by pmbr_part_valid()
 465  */
 466 static int is_pmbr_valid(legacy_mbr * mbr)
 467 {
 468         int i = 0;
 469
 470         if (!mbr || le16_to_cpu(mbr->signature) != MSDOS_MBR_SIGNATURE)
 471                 return 0;
 472
 473         for (i = 0; i < 4; i++) {
 474                 if (pmbr_part_valid(&mbr->partition_record[i])) {
 475                         return 1;
 476                 }
 477         }
 478         return 0;
 479 }
 480
 481 /**
 482  * is_gpt_valid() - tests one GPT header and PTEs for validity
 483  *
 484  * lba is the logical block address of the GPT header to test
 485  * gpt is a GPT header ptr, filled on return.
 486  * ptes is a PTEs ptr, filled on return.
 487  *
 488  * Description: returns 1 if valid,  0 on error.
 489  * If valid, returns pointers to PTEs.
 490  */
 491 static int is_gpt_valid(block_dev_desc_t * dev_desc, unsigned long long lba,
 492                         gpt_header * pgpt_head, gpt_entry ** pgpt_pte)
 493 {
 494         u32 crc32_backup = 0;
 495         u32 calc_crc32;
 496         unsigned long long lastlba;
 497
 498         if (!dev_desc || !pgpt_head) {
 499                 printf("%s: Invalid Argument(s)\n", __func__);
 500                 return 0;
 501         }
 502
 503         /* Read GPT Header from device */
 504         if (dev_desc->block_read(dev_desc->dev, lba, 1, pgpt_head) != 1) {
 505                 printf("*** ERROR: Can't read GPT header ***\n");
 506                 return 0;
 507         }
 508
 509         /* Check the GPT header signature */
 510         if (le64_to_cpu(pgpt_head->signature) != GPT_HEADER_SIGNATURE) {
 511                 printf("GUID Partition Table Header signature is wrong:"
 512                         "0x%llX != 0x%llX\n",
 513                         le64_to_cpu(pgpt_head->signature),
 514                         GPT_HEADER_SIGNATURE);
 515                 return 0;
 516         }
 517
 518         /* Check the GUID Partition Table CRC */
 519         memcpy(&crc32_backup, &pgpt_head->header_crc32, sizeof(crc32_backup));
 520         memset(&pgpt_head->header_crc32, 0, sizeof(pgpt_head->header_crc32));
 521
 522         calc_crc32 = efi_crc32((const unsigned char *)pgpt_head,
 523                 le32_to_cpu(pgpt_head->header_size));
 524
 525         memcpy(&pgpt_head->header_crc32, &crc32_backup, sizeof(crc32_backup));
 526
 527         if (calc_crc32 != le32_to_cpu(crc32_backup)) {
 528                 printf("GUID Partition Table Header CRC is wrong:"
 529                         "0x%x != 0x%x\n",
 530                        le32_to_cpu(crc32_backup), calc_crc32);
 531                 return 0;
 532         }
 533
 534         /* Check that the my_lba entry points to the LBA that contains the GPT */
 535         if (le64_to_cpu(pgpt_head->my_lba) != lba) {
 536                 printf("GPT: my_lba incorrect: %llX != %llX\n",
 537                         le64_to_cpu(pgpt_head->my_lba),
 538                         lba);
 539                 return 0;
 540         }
 541
 542         /* Check the first_usable_lba and last_usable_lba are within the disk. */
 543         lastlba = (unsigned long long)dev_desc->lba;
 544         if (le64_to_cpu(pgpt_head->first_usable_lba) > lastlba) {
 545                 printf("GPT: first_usable_lba incorrect: %llX > %llX\n",
 546                         le64_to_cpu(pgpt_head->first_usable_lba), lastlba);
 547                 return 0;
 548         }
 549         if (le64_to_cpu(pgpt_head->last_usable_lba) > lastlba) {
 550                 printf("GPT: last_usable_lba incorrect: %llX > %llX\n",
 551                         (u64) le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
 552                 return 0;
 553         }
 554
 555         debug("GPT: first_usable_lba: %llX last_usable_lba %llX last lba %llX\n",
 556                 le64_to_cpu(pgpt_head->first_usable_lba),
 557                 le64_to_cpu(pgpt_head->last_usable_lba), lastlba);
 558
 559         /* Read and allocate Partition Table Entries */
 560         *pgpt_pte = alloc_read_gpt_entries(dev_desc, pgpt_head);
 561         if (*pgpt_pte == NULL) {
 562                 printf("GPT: Failed to allocate memory for PTE\n");
 563                 return 0;
 564         }
 565
 566         /* Check the GUID Partition Table Entry Array CRC */
 567         calc_crc32 = efi_crc32((const unsigned char *)*pgpt_pte,
 568                 le32_to_cpu(pgpt_head->num_partition_entries) *
 569                 le32_to_cpu(pgpt_head->sizeof_partition_entry));
 570
 571         if (calc_crc32 != le32_to_cpu(pgpt_head->partition_entry_array_crc32)) {
 572                 printf("GUID Partition Table Entry Array CRC is wrong:"
 573                         "0x%x != 0x%x\n",
 574                         le32_to_cpu(pgpt_head->partition_entry_array_crc32),
 575                         calc_crc32);
 576
 577                 free(*pgpt_pte);
 578                 return 0;
 579         }
 580
 581         /* We're done, all's well */
 582         return 1;
 583 }
 584
 585 /**
 586  * alloc_read_gpt_entries(): reads partition entries from disk
 587  * @dev_desc
 588  * @gpt - GPT header
 589  *
 590  * Description: Returns ptes on success,  NULL on error.
 591  * Allocates space for PTEs based on information found in @gpt.
 592  * Notes: remember to free pte when you're done!
 593  */
 594 static gpt_entry *alloc_read_gpt_entries(block_dev_desc_t * dev_desc,
 595                                          gpt_header * pgpt_head)
 596 {
 597         size_t count = 0, blk_cnt;
 598         gpt_entry *pte = NULL;
 599
 600         if (!dev_desc || !pgpt_head) {
 601                 printf("%s: Invalid Argument(s)\n", __func__);
 602                 return NULL;
 603         }
 604
 605         count = le32_to_cpu(pgpt_head->num_partition_entries) *
 606                 le32_to_cpu(pgpt_head->sizeof_partition_entry);
 607
 608         debug("%s: count = %u * %u = %zu\n", __func__,
 609               (u32) le32_to_cpu(pgpt_head->num_partition_entries),
 610               (u32) le32_to_cpu(pgpt_head->sizeof_partition_entry), count);
 611
 612         /* Allocate memory for PTE, remember to FREE */
 613         if (count != 0) {
 614                 pte = memalign(ARCH_DMA_MINALIGN,
 615                                PAD_TO_BLOCKSIZE(count, dev_desc));
 616         }
 617
 618         if (count == 0 || pte == NULL) {
 619                 printf("%s: ERROR: Can't allocate 0x%zX "
 620                        "bytes for GPT Entries\n",
 621                         __func__, count);
 622                 return NULL;
 623         }
 624
 625         /* Read GPT Entries from device */
 626         blk_cnt = BLOCK_CNT(count, dev_desc);
 627         if (dev_desc->block_read (dev_desc->dev,
 628                 le64_to_cpu(pgpt_head->partition_entry_lba),
 629                 (lbaint_t) (blk_cnt), pte)
 630                 != blk_cnt) {
 631
 632                 printf("*** ERROR: Can't read GPT Entries ***\n");
 633                 free(pte);
 634                 return NULL;
 635         }
 636         return pte;
 637 }
 638
 639 /**
 640  * is_pte_valid(): validates a single Partition Table Entry
 641  * @gpt_entry - Pointer to a single Partition Table Entry
 642  *
 643  * Description: returns 1 if valid,  0 on error.
 644  */
 645 static int is_pte_valid(gpt_entry * pte)
 646 {
 647         efi_guid_t unused_guid;
 648
 649         if (!pte) {
 650                 printf("%s: Invalid Argument(s)\n", __func__);
 651                 return 0;
 652         }
 653
 654         /* Only one validation for now:
 655          * The GUID Partition Type != Unused Entry (ALL-ZERO)
 656          */
 657         memset(unused_guid.b, 0, sizeof(unused_guid.b));
 658
 659         if (memcmp(pte->partition_type_guid.b, unused_guid.b,
 660                 sizeof(unused_guid.b)) == 0) {
 661
 662                 debug("%s: Found an unused PTE GUID at 0x%08X\n", __func__,
 663                       (unsigned int)(uintptr_t)pte);
 664
 665                 return 0;
 666         } else {
 667                 return 1;
 668         }
 669 }
 670 #endif