lib/efi_loader/efi_image_loader.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *  EFI image loader
   4  *
   5  *  based partly on wine code
   6  *
   7  *  Copyright (c) 2016 Alexander Graf
   8  */
   9
  10 #include <common.h>
  11 #include <cpu_func.h>
  12 #include <efi_loader.h>
  13 #include <malloc.h>
  14 #include <pe.h>
  15 #include <sort.h>
  16 #include <crypto/pkcs7_parser.h>
  17 #include <linux/err.h>
  18
  19 const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
  20 const efi_guid_t efi_guid_device_path = EFI_DEVICE_PATH_PROTOCOL_GUID;
  21 const efi_guid_t efi_guid_loaded_image = EFI_LOADED_IMAGE_PROTOCOL_GUID;
  22 const efi_guid_t efi_guid_loaded_image_device_path =
  23                 EFI_LOADED_IMAGE_DEVICE_PATH_PROTOCOL_GUID;
  24 const efi_guid_t efi_simple_file_system_protocol_guid =
  25                 EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
  26 const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
  27
  28 static int machines[] = {
  29 #if defined(__aarch64__)
  30         IMAGE_FILE_MACHINE_ARM64,
  31 #elif defined(__arm__)
  32         IMAGE_FILE_MACHINE_ARM,
  33         IMAGE_FILE_MACHINE_THUMB,
  34         IMAGE_FILE_MACHINE_ARMNT,
  35 #endif
  36
  37 #if defined(__x86_64__)
  38         IMAGE_FILE_MACHINE_AMD64,
  39 #elif defined(__i386__)
  40         IMAGE_FILE_MACHINE_I386,
  41 #endif
  42
  43 #if defined(__riscv) && (__riscv_xlen == 32)
  44         IMAGE_FILE_MACHINE_RISCV32,
  45 #endif
  46
  47 #if defined(__riscv) && (__riscv_xlen == 64)
  48         IMAGE_FILE_MACHINE_RISCV64,
  49 #endif
  50         0 };
  51
  52 /**
  53  * efi_print_image_info() - print information about a loaded image
  54  *
  55  * If the program counter is located within the image the offset to the base
  56  * address is shown.
  57  *
  58  * @obj:        EFI object
  59  * @image:      loaded image
  60  * @pc:         program counter (use NULL to suppress offset output)
  61  * Return:      status code
  62  */
  63 static efi_status_t efi_print_image_info(struct efi_loaded_image_obj *obj,
  64                                          struct efi_loaded_image *image,
  65                                          void *pc)
  66 {
  67         printf("UEFI image");
  68         printf(" [0x%p:0x%p]",
  69                image->image_base, image->image_base + image->image_size - 1);
  70         if (pc && pc >= image->image_base &&
  71             pc < image->image_base + image->image_size)
  72                 printf(" pc=0x%zx", pc - image->image_base);
  73         if (image->file_path)
  74                 printf(" '%pD'", image->file_path);
  75         printf("\n");
  76         return EFI_SUCCESS;
  77 }
  78
  79 /**
  80  * efi_print_image_infos() - print information about all loaded images
  81  *
  82  * @pc:         program counter (use NULL to suppress offset output)
  83  */
  84 void efi_print_image_infos(void *pc)
  85 {
  86         struct efi_object *efiobj;
  87         struct efi_handler *handler;
  88
  89         list_for_each_entry(efiobj, &efi_obj_list, link) {
  90                 list_for_each_entry(handler, &efiobj->protocols, link) {
  91                         if (!guidcmp(handler->guid, &efi_guid_loaded_image)) {
  92                                 efi_print_image_info(
  93                                         (struct efi_loaded_image_obj *)efiobj,
  94                                         handler->protocol_interface, pc);
  95                         }
  96                 }
  97         }
  98 }
  99
 100 /**
 101  * efi_loader_relocate() - relocate UEFI binary
 102  *
 103  * @rel:                pointer to the relocation table
 104  * @rel_size:           size of the relocation table in bytes
 105  * @efi_reloc:          actual load address of the image
 106  * @pref_address:       preferred load address of the image
 107  * Return:              status code
 108  */
 109 static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
 110                         unsigned long rel_size, void *efi_reloc,
 111                         unsigned long pref_address)
 112 {
 113         unsigned long delta = (unsigned long)efi_reloc - pref_address;
 114         const IMAGE_BASE_RELOCATION *end;
 115         int i;
 116
 117         if (delta == 0)
 118                 return EFI_SUCCESS;
 119
 120         end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
 121         while (rel < end && rel->SizeOfBlock) {
 122                 const uint16_t *relocs = (const uint16_t *)(rel + 1);
 123                 i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
 124                 while (i--) {
 125                         uint32_t offset = (uint32_t)(*relocs & 0xfff) +
 126                                           rel->VirtualAddress;
 127                         int type = *relocs >> EFI_PAGE_SHIFT;
 128                         uint64_t *x64 = efi_reloc + offset;
 129                         uint32_t *x32 = efi_reloc + offset;
 130                         uint16_t *x16 = efi_reloc + offset;
 131
 132                         switch (type) {
 133                         case IMAGE_REL_BASED_ABSOLUTE:
 134                                 break;
 135                         case IMAGE_REL_BASED_HIGH:
 136                                 *x16 += ((uint32_t)delta) >> 16;
 137                                 break;
 138                         case IMAGE_REL_BASED_LOW:
 139                                 *x16 += (uint16_t)delta;
 140                                 break;
 141                         case IMAGE_REL_BASED_HIGHLOW:
 142                                 *x32 += (uint32_t)delta;
 143                                 break;
 144                         case IMAGE_REL_BASED_DIR64:
 145                                 *x64 += (uint64_t)delta;
 146                                 break;
 147 #ifdef __riscv
 148                         case IMAGE_REL_BASED_RISCV_HI20:
 149                                 *x32 = ((*x32 & 0xfffff000) + (uint32_t)delta) |
 150                                         (*x32 & 0x00000fff);
 151                                 break;
 152                         case IMAGE_REL_BASED_RISCV_LOW12I:
 153                         case IMAGE_REL_BASED_RISCV_LOW12S:
 154                                 /* We know that we're 4k aligned */
 155                                 if (delta & 0xfff) {
 156                                         printf("Unsupported reloc offset\n");
 157                                         return EFI_LOAD_ERROR;
 158                                 }
 159                                 break;
 160 #endif
 161                         default:
 162                                 printf("Unknown Relocation off %x type %x\n",
 163                                        offset, type);
 164                                 return EFI_LOAD_ERROR;
 165                         }
 166                         relocs++;
 167                 }
 168                 rel = (const IMAGE_BASE_RELOCATION *)relocs;
 169         }
 170         return EFI_SUCCESS;
 171 }
 172
 173 void __weak invalidate_icache_all(void)
 174 {
 175         /* If the system doesn't support icache_all flush, cross our fingers */
 176 }
 177
 178 /**
 179  * efi_set_code_and_data_type() - determine the memory types to be used for code
 180  *                                and data.
 181  *
 182  * @loaded_image_info:  image descriptor
 183  * @image_type:         field Subsystem of the optional header for
 184  *                      Windows specific field
 185  */
 186 static void efi_set_code_and_data_type(
 187                         struct efi_loaded_image *loaded_image_info,
 188                         uint16_t image_type)
 189 {
 190         switch (image_type) {
 191         case IMAGE_SUBSYSTEM_EFI_APPLICATION:
 192                 loaded_image_info->image_code_type = EFI_LOADER_CODE;
 193                 loaded_image_info->image_data_type = EFI_LOADER_DATA;
 194                 break;
 195         case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
 196                 loaded_image_info->image_code_type = EFI_BOOT_SERVICES_CODE;
 197                 loaded_image_info->image_data_type = EFI_BOOT_SERVICES_DATA;
 198                 break;
 199         case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
 200         case IMAGE_SUBSYSTEM_EFI_ROM:
 201                 loaded_image_info->image_code_type = EFI_RUNTIME_SERVICES_CODE;
 202                 loaded_image_info->image_data_type = EFI_RUNTIME_SERVICES_DATA;
 203                 break;
 204         default:
 205                 printf("%s: invalid image type: %u\n", __func__, image_type);
 206                 /* Let's assume it is an application */
 207                 loaded_image_info->image_code_type = EFI_LOADER_CODE;
 208                 loaded_image_info->image_data_type = EFI_LOADER_DATA;
 209                 break;
 210         }
 211 }
 212
 213 #ifdef CONFIG_EFI_SECURE_BOOT
 214 /**
 215  * cmp_pe_section() - compare virtual addresses of two PE image sections
 216  * @arg1:       pointer to pointer to first section header
 217  * @arg2:       pointer to pointer to second section header
 218  *
 219  * Compare the virtual addresses of two sections of an portable executable.
 220  * The arguments are defined as const void * to allow usage with qsort().
 221  *
 222  * Return:      -1 if the virtual address of arg1 is less than that of arg2,
 223  *              0 if the virtual addresses are equal, 1 if the virtual address
 224  *              of arg1 is greater than that of arg2.
 225  */
 226 static int cmp_pe_section(const void *arg1, const void *arg2)
 227 {
 228         const IMAGE_SECTION_HEADER *section1, *section2;
 229
 230         section1 = *((const IMAGE_SECTION_HEADER **)arg1);
 231         section2 = *((const IMAGE_SECTION_HEADER **)arg2);
 232
 233         if (section1->VirtualAddress < section2->VirtualAddress)
 234                 return -1;
 235         else if (section1->VirtualAddress == section2->VirtualAddress)
 236                 return 0;
 237         else
 238                 return 1;
 239 }
 240
 241 /**
 242  * efi_image_parse() - parse a PE image
 243  * @efi:        Pointer to image
 244  * @len:        Size of @efi
 245  * @regp:       Pointer to a list of regions
 246  * @auth:       Pointer to a pointer to authentication data in PE
 247  * @auth_len:   Size of @auth
 248  *
 249  * Parse image binary in PE32(+) format, assuming that sanity of PE image
 250  * has been checked by a caller.
 251  * On success, an address of authentication data in @efi and its size will
 252  * be returned in @auth and @auth_len, respectively.
 253  *
 254  * Return:      true on success, false on error
 255  */
 256 bool efi_image_parse(void *efi, size_t len, struct efi_image_regions **regp,
 257                      WIN_CERTIFICATE **auth, size_t *auth_len)
 258 {
 259         struct efi_image_regions *regs;
 260         IMAGE_DOS_HEADER *dos;
 261         IMAGE_NT_HEADERS32 *nt;
 262         IMAGE_SECTION_HEADER *sections, **sorted;
 263         int num_regions, num_sections, i;
 264         int ctidx = IMAGE_DIRECTORY_ENTRY_SECURITY;
 265         u32 align, size, authsz, authoff;
 266         size_t bytes_hashed;
 267
 268         dos = (void *)efi;
 269         nt = (void *)(efi + dos->e_lfanew);
 270
 271         /*
 272          * Count maximum number of regions to be digested.
 273          * We don't have to have an exact number here.
 274          * See efi_image_region_add()'s in parsing below.
 275          */
 276         num_regions = 3; /* for header */
 277         num_regions += nt->FileHeader.NumberOfSections;
 278         num_regions++; /* for extra */
 279
 280         regs = calloc(sizeof(*regs) + sizeof(struct image_region) * num_regions,
 281                       1);
 282         if (!regs)
 283                 goto err;
 284         regs->max = num_regions;
 285
 286         /*
 287          * Collect data regions for hash calculation
 288          * 1. File headers
 289          */
 290         if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 291                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 292                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 293
 294                 /* Skip CheckSum */
 295                 efi_image_region_add(regs, efi, &opt->CheckSum, 0);
 296                 if (nt64->OptionalHeader.NumberOfRvaAndSizes <= ctidx) {
 297                         efi_image_region_add(regs,
 298                                              &opt->Subsystem,
 299                                              efi + opt->SizeOfHeaders, 0);
 300                 } else {
 301                         /* Skip Certificates Table */
 302                         efi_image_region_add(regs,
 303                                              &opt->Subsystem,
 304                                              &opt->DataDirectory[ctidx], 0);
 305                         efi_image_region_add(regs,
 306                                              &opt->DataDirectory[ctidx] + 1,
 307                                              efi + opt->SizeOfHeaders, 0);
 308                 }
 309
 310                 bytes_hashed = opt->SizeOfHeaders;
 311                 align = opt->FileAlignment;
 312                 authoff = opt->DataDirectory[ctidx].VirtualAddress;
 313                 authsz = opt->DataDirectory[ctidx].Size;
 314         } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 315                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 316
 317                 efi_image_region_add(regs, efi, &opt->CheckSum, 0);
 318                 efi_image_region_add(regs, &opt->Subsystem,
 319                                      &opt->DataDirectory[ctidx], 0);
 320                 efi_image_region_add(regs, &opt->DataDirectory[ctidx] + 1,
 321                                      efi + opt->SizeOfHeaders, 0);
 322
 323                 bytes_hashed = opt->SizeOfHeaders;
 324                 align = opt->FileAlignment;
 325                 authoff = opt->DataDirectory[ctidx].VirtualAddress;
 326                 authsz = opt->DataDirectory[ctidx].Size;
 327         } else {
 328                 debug("%s: Invalid optional header magic %x\n", __func__,
 329                       nt->OptionalHeader.Magic);
 330                 goto err;
 331         }
 332
 333         /* 2. Sections */
 334         num_sections = nt->FileHeader.NumberOfSections;
 335         sections = (void *)((uint8_t *)&nt->OptionalHeader +
 336                             nt->FileHeader.SizeOfOptionalHeader);
 337         sorted = calloc(sizeof(IMAGE_SECTION_HEADER *), num_sections);
 338         if (!sorted) {
 339                 debug("%s: Out of memory\n", __func__);
 340                 goto err;
 341         }
 342
 343         /*
 344          * Make sure the section list is in ascending order.
 345          */
 346         for (i = 0; i < num_sections; i++)
 347                 sorted[i] = &sections[i];
 348         qsort(sorted, num_sections, sizeof(sorted[0]), cmp_pe_section);
 349
 350         for (i = 0; i < num_sections; i++) {
 351                 if (!sorted[i]->SizeOfRawData)
 352                         continue;
 353
 354                 size = (sorted[i]->SizeOfRawData + align - 1) & ~(align - 1);
 355                 efi_image_region_add(regs, efi + sorted[i]->PointerToRawData,
 356                                      efi + sorted[i]->PointerToRawData + size,
 357                                      0);
 358                 debug("section[%d](%s): raw: 0x%x-0x%x, virt: %x-%x\n",
 359                       i, sorted[i]->Name,
 360                       sorted[i]->PointerToRawData,
 361                       sorted[i]->PointerToRawData + size,
 362                       sorted[i]->VirtualAddress,
 363                       sorted[i]->VirtualAddress
 364                         + sorted[i]->Misc.VirtualSize);
 365
 366                 bytes_hashed += size;
 367         }
 368         free(sorted);
 369
 370         /* 3. Extra data excluding Certificates Table */
 371         if (bytes_hashed + authsz < len) {
 372                 debug("extra data for hash: %zu\n",
 373                       len - (bytes_hashed + authsz));
 374                 efi_image_region_add(regs, efi + bytes_hashed,
 375                                      efi + len - authsz, 0);
 376         }
 377
 378         /* Return Certificates Table */
 379         if (authsz) {
 380                 if (len < authoff + authsz) {
 381                         debug("%s: Size for auth too large: %u >= %zu\n",
 382                               __func__, authsz, len - authoff);
 383                         goto err;
 384                 }
 385                 if (authsz < sizeof(*auth)) {
 386                         debug("%s: Size for auth too small: %u < %zu\n",
 387                               __func__, authsz, sizeof(*auth));
 388                         goto err;
 389                 }
 390                 *auth = efi + authoff;
 391                 *auth_len = authsz;
 392                 debug("WIN_CERTIFICATE: 0x%x, size: 0x%x\n", authoff, authsz);
 393         } else {
 394                 *auth = NULL;
 395                 *auth_len = 0;
 396         }
 397
 398         *regp = regs;
 399
 400         return true;
 401
 402 err:
 403         free(regs);
 404
 405         return false;
 406 }
 407
 408 /**
 409  * efi_image_unsigned_authenticate() - authenticate unsigned image with
 410  * SHA256 hash
 411  * @regs:       List of regions to be verified
 412  *
 413  * If an image is not signed, it doesn't have a signature. In this case,
 414  * its message digest is calculated and it will be compared with one of
 415  * hash values stored in signature databases.
 416  *
 417  * Return:      true if authenticated, false if not
 418  */
 419 static bool efi_image_unsigned_authenticate(struct efi_image_regions *regs)
 420 {
 421         struct efi_signature_store *db = NULL, *dbx = NULL;
 422         bool ret = false;
 423
 424         dbx = efi_sigstore_parse_sigdb(L"dbx");
 425         if (!dbx) {
 426                 debug("Getting signature database(dbx) failed\n");
 427                 goto out;
 428         }
 429
 430         db = efi_sigstore_parse_sigdb(L"db");
 431         if (!db) {
 432                 debug("Getting signature database(db) failed\n");
 433                 goto out;
 434         }
 435
 436         /* try black-list first */
 437         if (efi_signature_verify_with_sigdb(regs, NULL, dbx, NULL)) {
 438                 debug("Image is not signed and rejected by \"dbx\"\n");
 439                 goto out;
 440         }
 441
 442         /* try white-list */
 443         if (efi_signature_verify_with_sigdb(regs, NULL, db, NULL))
 444                 ret = true;
 445         else
 446                 debug("Image is not signed and not found in \"db\" or \"dbx\"\n");
 447
 448 out:
 449         efi_sigstore_free(db);
 450         efi_sigstore_free(dbx);
 451
 452         return ret;
 453 }
 454
 455 /**
 456  * efi_image_authenticate() - verify a signature of signed image
 457  * @efi:        Pointer to image
 458  * @efi_size:   Size of @efi
 459  *
 460  * A signed image should have its signature stored in a table of its PE header.
 461  * So if an image is signed and only if if its signature is verified using
 462  * signature databases, an image is authenticated.
 463  * If an image is not signed, its validity is checked by using
 464  * efi_image_unsigned_authenticated().
 465  * TODO:
 466  * When AuditMode==0, if the image's signature is not found in
 467  * the authorized database, or is found in the forbidden database,
 468  * the image will not be started and instead, information about it
 469  * will be placed in this table.
 470  * When AuditMode==1, an EFI_IMAGE_EXECUTION_INFO element is created
 471  * in the EFI_IMAGE_EXECUTION_INFO_TABLE for every certificate found
 472  * in the certificate table of every image that is validated.
 473  *
 474  * Return:      true if authenticated, false if not
 475  */
 476 static bool efi_image_authenticate(void *efi, size_t efi_size)
 477 {
 478         struct efi_image_regions *regs = NULL;
 479         WIN_CERTIFICATE *wincerts = NULL, *wincert;
 480         size_t wincerts_len;
 481         struct pkcs7_message *msg = NULL;
 482         struct efi_signature_store *db = NULL, *dbx = NULL;
 483         struct x509_certificate *cert = NULL;
 484         void *new_efi = NULL;
 485         size_t new_efi_size;
 486         bool ret = false;
 487
 488         if (!efi_secure_boot_enabled())
 489                 return true;
 490
 491         /*
 492          * Size must be 8-byte aligned and the trailing bytes must be
 493          * zero'ed. Otherwise hash value may be incorrect.
 494          */
 495         if (efi_size & 0x7) {
 496                 new_efi_size = (efi_size + 0x7) & ~0x7ULL;
 497                 new_efi = calloc(new_efi_size, 1);
 498                 if (!new_efi)
 499                         return false;
 500                 memcpy(new_efi, efi, efi_size);
 501                 efi = new_efi;
 502                 efi_size = new_efi_size;
 503         }
 504
 505         if (!efi_image_parse(efi, efi_size, &regs, &wincerts,
 506                              &wincerts_len)) {
 507                 debug("Parsing PE executable image failed\n");
 508                 goto err;
 509         }
 510
 511         if (!wincerts) {
 512                 /* The image is not signed */
 513                 ret = efi_image_unsigned_authenticate(regs);
 514
 515                 goto err;
 516         }
 517
 518         /*
 519          * verify signature using db and dbx
 520          */
 521         db = efi_sigstore_parse_sigdb(L"db");
 522         if (!db) {
 523                 debug("Getting signature database(db) failed\n");
 524                 goto err;
 525         }
 526
 527         dbx = efi_sigstore_parse_sigdb(L"dbx");
 528         if (!dbx) {
 529                 debug("Getting signature database(dbx) failed\n");
 530                 goto err;
 531         }
 532
 533         /* go through WIN_CERTIFICATE list */
 534         for (wincert = wincerts;
 535              (void *)wincert < (void *)wincerts + wincerts_len;
 536              wincert = (void *)wincert + ALIGN(wincert->dwLength, 8)) {
 537                 if (wincert->dwLength < sizeof(*wincert)) {
 538                         debug("%s: dwLength too small: %u < %zu\n",
 539                               __func__, wincert->dwLength, sizeof(*wincert));
 540                         goto err;
 541                 }
 542                 msg = pkcs7_parse_message((void *)wincert + sizeof(*wincert),
 543                                           wincert->dwLength - sizeof(*wincert));
 544                 if (IS_ERR(msg)) {
 545                         debug("Parsing image's signature failed\n");
 546                         msg = NULL;
 547                         goto err;
 548                 }
 549
 550                 /* try black-list first */
 551                 if (efi_signature_verify_with_sigdb(regs, msg, dbx, NULL)) {
 552                         debug("Signature was rejected by \"dbx\"\n");
 553                         goto err;
 554                 }
 555
 556                 if (!efi_signature_verify_signers(msg, dbx)) {
 557                         debug("Signer was rejected by \"dbx\"\n");
 558                         goto err;
 559                 } else {
 560                         ret = true;
 561                 }
 562
 563                 /* try white-list */
 564                 if (!efi_signature_verify_with_sigdb(regs, msg, db, &cert)) {
 565                         debug("Verifying signature with \"db\" failed\n");
 566                         goto err;
 567                 } else {
 568                         ret = true;
 569                 }
 570
 571                 if (!efi_signature_verify_cert(cert, dbx)) {
 572                         debug("Certificate was rejected by \"dbx\"\n");
 573                         goto err;
 574                 } else {
 575                         ret = true;
 576                 }
 577         }
 578
 579 err:
 580         x509_free_certificate(cert);
 581         efi_sigstore_free(db);
 582         efi_sigstore_free(dbx);
 583         pkcs7_free_message(msg);
 584         free(regs);
 585         free(new_efi);
 586
 587         return ret;
 588 }
 589 #else
 590 static bool efi_image_authenticate(void *efi, size_t efi_size)
 591 {
 592         return true;
 593 }
 594 #endif /* CONFIG_EFI_SECURE_BOOT */
 595
 596 /**
 597  * efi_load_pe() - relocate EFI binary
 598  *
 599  * This function loads all sections from a PE binary into a newly reserved
 600  * piece of memory. On success the entry point is returned as handle->entry.
 601  *
 602  * @handle:             loaded image handle
 603  * @efi:                pointer to the EFI binary
 604  * @efi_size:           size of @efi binary
 605  * @loaded_image_info:  loaded image protocol
 606  * Return:              status code
 607  */
 608 efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
 609                          void *efi, size_t efi_size,
 610                          struct efi_loaded_image *loaded_image_info)
 611 {
 612         IMAGE_NT_HEADERS32 *nt;
 613         IMAGE_DOS_HEADER *dos;
 614         IMAGE_SECTION_HEADER *sections;
 615         int num_sections;
 616         void *efi_reloc;
 617         int i;
 618         const IMAGE_BASE_RELOCATION *rel;
 619         unsigned long rel_size;
 620         int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
 621         uint64_t image_base;
 622         unsigned long virt_size = 0;
 623         int supported = 0;
 624         efi_status_t ret;
 625
 626         /* Sanity check for a file header */
 627         if (efi_size < sizeof(*dos)) {
 628                 printf("%s: Truncated DOS Header\n", __func__);
 629                 ret = EFI_LOAD_ERROR;
 630                 goto err;
 631         }
 632
 633         dos = efi;
 634         if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 635                 printf("%s: Invalid DOS Signature\n", __func__);
 636                 ret = EFI_LOAD_ERROR;
 637                 goto err;
 638         }
 639
 640         /*
 641          * Check if the image section header fits into the file. Knowing that at
 642          * least one section header follows we only need to check for the length
 643          * of the 64bit header which is longer than the 32bit header.
 644          */
 645         if (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS64)) {
 646                 printf("%s: Invalid offset for Extended Header\n", __func__);
 647                 ret = EFI_LOAD_ERROR;
 648                 goto err;
 649         }
 650
 651         nt = (void *) ((char *)efi + dos->e_lfanew);
 652         if (nt->Signature != IMAGE_NT_SIGNATURE) {
 653                 printf("%s: Invalid NT Signature\n", __func__);
 654                 ret = EFI_LOAD_ERROR;
 655                 goto err;
 656         }
 657
 658         for (i = 0; machines[i]; i++)
 659                 if (machines[i] == nt->FileHeader.Machine) {
 660                         supported = 1;
 661                         break;
 662                 }
 663
 664         if (!supported) {
 665                 printf("%s: Machine type 0x%04x is not supported\n",
 666                        __func__, nt->FileHeader.Machine);
 667                 ret = EFI_LOAD_ERROR;
 668                 goto err;
 669         }
 670
 671         num_sections = nt->FileHeader.NumberOfSections;
 672         sections = (void *)&nt->OptionalHeader +
 673                             nt->FileHeader.SizeOfOptionalHeader;
 674
 675         if (efi_size < ((void *)sections + sizeof(sections[0]) * num_sections
 676                         - efi)) {
 677                 printf("%s: Invalid number of sections: %d\n",
 678                        __func__, num_sections);
 679                 ret = EFI_LOAD_ERROR;
 680                 goto err;
 681         }
 682
 683         /* Authenticate an image */
 684         if (efi_image_authenticate(efi, efi_size))
 685                 handle->auth_status = EFI_IMAGE_AUTH_PASSED;
 686         else
 687                 handle->auth_status = EFI_IMAGE_AUTH_FAILED;
 688
 689         /* Calculate upper virtual address boundary */
 690         for (i = num_sections - 1; i >= 0; i--) {
 691                 IMAGE_SECTION_HEADER *sec = &sections[i];
 692                 virt_size = max_t(unsigned long, virt_size,
 693                                   sec->VirtualAddress + sec->Misc.VirtualSize);
 694         }
 695
 696         /* Read 32/64bit specific header bits */
 697         if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 698                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 699                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 700                 image_base = opt->ImageBase;
 701                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 702                 handle->image_type = opt->Subsystem;
 703                 efi_reloc = efi_alloc(virt_size,
 704                                       loaded_image_info->image_code_type);
 705                 if (!efi_reloc) {
 706                         printf("%s: Could not allocate %lu bytes\n",
 707                                __func__, virt_size);
 708                         ret = EFI_OUT_OF_RESOURCES;
 709                         goto err;
 710                 }
 711                 handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 712                 rel_size = opt->DataDirectory[rel_idx].Size;
 713                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 714                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 715         } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 716                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 717                 image_base = opt->ImageBase;
 718                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 719                 handle->image_type = opt->Subsystem;
 720                 efi_reloc = efi_alloc(virt_size,
 721                                       loaded_image_info->image_code_type);
 722                 if (!efi_reloc) {
 723                         printf("%s: Could not allocate %lu bytes\n",
 724                                __func__, virt_size);
 725                         ret = EFI_OUT_OF_RESOURCES;
 726                         goto err;
 727                 }
 728                 handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 729                 rel_size = opt->DataDirectory[rel_idx].Size;
 730                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 731                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 732         } else {
 733                 printf("%s: Invalid optional header magic %x\n", __func__,
 734                        nt->OptionalHeader.Magic);
 735                 ret = EFI_LOAD_ERROR;
 736                 goto err;
 737         }
 738
 739         /* Copy PE headers */
 740         memcpy(efi_reloc, efi,
 741                sizeof(*dos)
 742                  + sizeof(*nt)
 743                  + nt->FileHeader.SizeOfOptionalHeader
 744                  + num_sections * sizeof(IMAGE_SECTION_HEADER));
 745
 746         /* Load sections into RAM */
 747         for (i = num_sections - 1; i >= 0; i--) {
 748                 IMAGE_SECTION_HEADER *sec = &sections[i];
 749                 memset(efi_reloc + sec->VirtualAddress, 0,
 750                        sec->Misc.VirtualSize);
 751                 memcpy(efi_reloc + sec->VirtualAddress,
 752                        efi + sec->PointerToRawData,
 753                        sec->SizeOfRawData);
 754         }
 755
 756         /* Run through relocations */
 757         if (efi_loader_relocate(rel, rel_size, efi_reloc,
 758                                 (unsigned long)image_base) != EFI_SUCCESS) {
 759                 efi_free_pages((uintptr_t) efi_reloc,
 760                                (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 761                 ret = EFI_LOAD_ERROR;
 762                 goto err;
 763         }
 764
 765         /* Flush cache */
 766         flush_cache((ulong)efi_reloc,
 767                     ALIGN(virt_size, EFI_CACHELINE_SIZE));
 768         invalidate_icache_all();
 769
 770         /* Populate the loaded image interface bits */
 771         loaded_image_info->image_base = efi_reloc;
 772         loaded_image_info->image_size = virt_size;
 773
 774         if (handle->auth_status == EFI_IMAGE_AUTH_PASSED)
 775                 return EFI_SUCCESS;
 776         else
 777                 return EFI_SECURITY_VIOLATION;
 778
 779 err:
 780         return ret;
 781 }