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                 EFI_PRINT("%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                 EFI_PRINT("%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                 EFI_PRINT("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                 EFI_PRINT("extra data for hash: %lu\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                         EFI_PRINT("%s: Size for auth too large: %u >= %zu\n",
 382                                   __func__, authsz, len - authoff);
 383                         goto err;
 384                 }
 385                 if (authsz < sizeof(*auth)) {
 386                         EFI_PRINT("%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                 EFI_PRINT("WIN_CERTIFICATE: 0x%x, size: 0x%x\n", authoff,
 393                           authsz);
 394         } else {
 395                 *auth = NULL;
 396                 *auth_len = 0;
 397         }
 398
 399         *regp = regs;
 400
 401         return true;
 402
 403 err:
 404         free(regs);
 405
 406         return false;
 407 }
 408
 409 /**
 410  * efi_image_unsigned_authenticate() - authenticate unsigned image with
 411  * SHA256 hash
 412  * @regs:       List of regions to be verified
 413  *
 414  * If an image is not signed, it doesn't have a signature. In this case,
 415  * its message digest is calculated and it will be compared with one of
 416  * hash values stored in signature databases.
 417  *
 418  * Return:      true if authenticated, false if not
 419  */
 420 static bool efi_image_unsigned_authenticate(struct efi_image_regions *regs)
 421 {
 422         struct efi_signature_store *db = NULL, *dbx = NULL;
 423         bool ret = false;
 424
 425         dbx = efi_sigstore_parse_sigdb(L"dbx");
 426         if (!dbx) {
 427                 EFI_PRINT("Getting signature database(dbx) failed\n");
 428                 goto out;
 429         }
 430
 431         db = efi_sigstore_parse_sigdb(L"db");
 432         if (!db) {
 433                 EFI_PRINT("Getting signature database(db) failed\n");
 434                 goto out;
 435         }
 436
 437         /* try black-list first */
 438         if (efi_signature_verify_with_sigdb(regs, NULL, dbx, NULL)) {
 439                 EFI_PRINT("Image is not signed and rejected by \"dbx\"\n");
 440                 goto out;
 441         }
 442
 443         /* try white-list */
 444         if (efi_signature_verify_with_sigdb(regs, NULL, db, NULL))
 445                 ret = true;
 446         else
 447                 EFI_PRINT("Image is not signed and not found in \"db\" or \"dbx\"\n");
 448
 449 out:
 450         efi_sigstore_free(db);
 451         efi_sigstore_free(dbx);
 452
 453         return ret;
 454 }
 455
 456 /**
 457  * efi_image_authenticate() - verify a signature of signed image
 458  * @efi:        Pointer to image
 459  * @efi_size:   Size of @efi
 460  *
 461  * A signed image should have its signature stored in a table of its PE header.
 462  * So if an image is signed and only if if its signature is verified using
 463  * signature databases, an image is authenticated.
 464  * If an image is not signed, its validity is checked by using
 465  * efi_image_unsigned_authenticated().
 466  * TODO:
 467  * When AuditMode==0, if the image's signature is not found in
 468  * the authorized database, or is found in the forbidden database,
 469  * the image will not be started and instead, information about it
 470  * will be placed in this table.
 471  * When AuditMode==1, an EFI_IMAGE_EXECUTION_INFO element is created
 472  * in the EFI_IMAGE_EXECUTION_INFO_TABLE for every certificate found
 473  * in the certificate table of every image that is validated.
 474  *
 475  * Return:      true if authenticated, false if not
 476  */
 477 static bool efi_image_authenticate(void *efi, size_t efi_size)
 478 {
 479         struct efi_image_regions *regs = NULL;
 480         WIN_CERTIFICATE *wincerts = NULL, *wincert;
 481         size_t wincerts_len;
 482         struct pkcs7_message *msg = NULL;
 483         struct efi_signature_store *db = NULL, *dbx = NULL;
 484         struct x509_certificate *cert = NULL;
 485         void *new_efi = NULL;
 486         u8 *auth, *wincerts_end;
 487         size_t new_efi_size, auth_size;
 488         bool ret = false;
 489
 490         if (!efi_secure_boot_enabled())
 491                 return true;
 492
 493         /*
 494          * Size must be 8-byte aligned and the trailing bytes must be
 495          * zero'ed. Otherwise hash value may be incorrect.
 496          */
 497         if (efi_size & 0x7) {
 498                 new_efi_size = (efi_size + 0x7) & ~0x7ULL;
 499                 new_efi = calloc(new_efi_size, 1);
 500                 if (!new_efi)
 501                         return false;
 502                 memcpy(new_efi, efi, efi_size);
 503                 efi = new_efi;
 504                 efi_size = new_efi_size;
 505         }
 506
 507         if (!efi_image_parse(efi, efi_size, &regs, &wincerts,
 508                              &wincerts_len)) {
 509                 EFI_PRINT("Parsing PE executable image failed\n");
 510                 goto err;
 511         }
 512
 513         if (!wincerts) {
 514                 /* The image is not signed */
 515                 ret = efi_image_unsigned_authenticate(regs);
 516
 517                 goto err;
 518         }
 519
 520         /*
 521          * verify signature using db and dbx
 522          */
 523         db = efi_sigstore_parse_sigdb(L"db");
 524         if (!db) {
 525                 EFI_PRINT("Getting signature database(db) failed\n");
 526                 goto err;
 527         }
 528
 529         dbx = efi_sigstore_parse_sigdb(L"dbx");
 530         if (!dbx) {
 531                 EFI_PRINT("Getting signature database(dbx) failed\n");
 532                 goto err;
 533         }
 534
 535         /* go through WIN_CERTIFICATE list */
 536         for (wincert = wincerts, wincerts_end = (u8 *)wincerts + wincerts_len;
 537              (u8 *)wincert < wincerts_end;
 538              wincert = (WIN_CERTIFICATE *)
 539                         ((u8 *)wincert + ALIGN(wincert->dwLength, 8))) {
 540                 if ((u8 *)wincert + sizeof(*wincert) >= wincerts_end)
 541                         break;
 542
 543                 if (wincert->dwLength <= sizeof(*wincert)) {
 544                         EFI_PRINT("dwLength too small: %u < %zu\n",
 545                                   wincert->dwLength, sizeof(*wincert));
 546                         continue;
 547                 }
 548
 549                 EFI_PRINT("WIN_CERTIFICATE_TYPE: 0x%x\n",
 550                           wincert->wCertificateType);
 551
 552                 auth = (u8 *)wincert + sizeof(*wincert);
 553                 auth_size = wincert->dwLength - sizeof(*wincert);
 554                 if (wincert->wCertificateType == WIN_CERT_TYPE_EFI_GUID) {
 555                         if (auth + sizeof(efi_guid_t) >= wincerts_end)
 556                                 break;
 557
 558                         if (auth_size <= sizeof(efi_guid_t)) {
 559                                 EFI_PRINT("dwLength too small: %u < %zu\n",
 560                                           wincert->dwLength, sizeof(*wincert));
 561                                 continue;
 562                         }
 563                         if (guidcmp(auth, &efi_guid_cert_type_pkcs7)) {
 564                                 EFI_PRINT("Certificate type not supported: %pUl\n",
 565                                           auth);
 566                                 continue;
 567                         }
 568
 569                         auth += sizeof(efi_guid_t);
 570                         auth_size -= sizeof(efi_guid_t);
 571                 } else if (wincert->wCertificateType
 572                                 != WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
 573                         EFI_PRINT("Certificate type not supported\n");
 574                         continue;
 575                 }
 576
 577                 msg = pkcs7_parse_message(auth, auth_size);
 578                 if (IS_ERR(msg)) {
 579                         EFI_PRINT("Parsing image's signature failed\n");
 580                         msg = NULL;
 581                         continue;
 582                 }
 583
 584                 /* try black-list first */
 585                 if (efi_signature_verify_with_sigdb(regs, msg, dbx, NULL)) {
 586                         EFI_PRINT("Signature was rejected by \"dbx\"\n");
 587                         goto err;
 588                 }
 589
 590                 if (!efi_signature_verify_signers(msg, dbx)) {
 591                         EFI_PRINT("Signer was rejected by \"dbx\"\n");
 592                         goto err;
 593                 } else {
 594                         ret = true;
 595                 }
 596
 597                 /* try white-list */
 598                 if (!efi_signature_verify_with_sigdb(regs, msg, db, &cert)) {
 599                         EFI_PRINT("Verifying signature with \"db\" failed\n");
 600                         goto err;
 601                 } else {
 602                         ret = true;
 603                 }
 604
 605                 if (!efi_signature_verify_cert(cert, dbx)) {
 606                         EFI_PRINT("Certificate was rejected by \"dbx\"\n");
 607                         goto err;
 608                 } else {
 609                         ret = true;
 610                 }
 611         }
 612
 613 err:
 614         x509_free_certificate(cert);
 615         efi_sigstore_free(db);
 616         efi_sigstore_free(dbx);
 617         pkcs7_free_message(msg);
 618         free(regs);
 619         free(new_efi);
 620
 621         return ret;
 622 }
 623 #else
 624 static bool efi_image_authenticate(void *efi, size_t efi_size)
 625 {
 626         return true;
 627 }
 628 #endif /* CONFIG_EFI_SECURE_BOOT */
 629
 630 /**
 631  * efi_load_pe() - relocate EFI binary
 632  *
 633  * This function loads all sections from a PE binary into a newly reserved
 634  * piece of memory. On success the entry point is returned as handle->entry.
 635  *
 636  * @handle:             loaded image handle
 637  * @efi:                pointer to the EFI binary
 638  * @efi_size:           size of @efi binary
 639  * @loaded_image_info:  loaded image protocol
 640  * Return:              status code
 641  */
 642 efi_status_t efi_load_pe(struct efi_loaded_image_obj *handle,
 643                          void *efi, size_t efi_size,
 644                          struct efi_loaded_image *loaded_image_info)
 645 {
 646         IMAGE_NT_HEADERS32 *nt;
 647         IMAGE_DOS_HEADER *dos;
 648         IMAGE_SECTION_HEADER *sections;
 649         int num_sections;
 650         void *efi_reloc;
 651         int i;
 652         const IMAGE_BASE_RELOCATION *rel;
 653         unsigned long rel_size;
 654         int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
 655         uint64_t image_base;
 656         unsigned long virt_size = 0;
 657         int supported = 0;
 658         efi_status_t ret;
 659
 660         /* Sanity check for a file header */
 661         if (efi_size < sizeof(*dos)) {
 662                 printf("%s: Truncated DOS Header\n", __func__);
 663                 ret = EFI_LOAD_ERROR;
 664                 goto err;
 665         }
 666
 667         dos = efi;
 668         if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 669                 printf("%s: Invalid DOS Signature\n", __func__);
 670                 ret = EFI_LOAD_ERROR;
 671                 goto err;
 672         }
 673
 674         /*
 675          * Check if the image section header fits into the file. Knowing that at
 676          * least one section header follows we only need to check for the length
 677          * of the 64bit header which is longer than the 32bit header.
 678          */
 679         if (efi_size < dos->e_lfanew + sizeof(IMAGE_NT_HEADERS64)) {
 680                 printf("%s: Invalid offset for Extended Header\n", __func__);
 681                 ret = EFI_LOAD_ERROR;
 682                 goto err;
 683         }
 684
 685         nt = (void *) ((char *)efi + dos->e_lfanew);
 686         if (nt->Signature != IMAGE_NT_SIGNATURE) {
 687                 printf("%s: Invalid NT Signature\n", __func__);
 688                 ret = EFI_LOAD_ERROR;
 689                 goto err;
 690         }
 691
 692         for (i = 0; machines[i]; i++)
 693                 if (machines[i] == nt->FileHeader.Machine) {
 694                         supported = 1;
 695                         break;
 696                 }
 697
 698         if (!supported) {
 699                 printf("%s: Machine type 0x%04x is not supported\n",
 700                        __func__, nt->FileHeader.Machine);
 701                 ret = EFI_LOAD_ERROR;
 702                 goto err;
 703         }
 704
 705         num_sections = nt->FileHeader.NumberOfSections;
 706         sections = (void *)&nt->OptionalHeader +
 707                             nt->FileHeader.SizeOfOptionalHeader;
 708
 709         if (efi_size < ((void *)sections + sizeof(sections[0]) * num_sections
 710                         - efi)) {
 711                 printf("%s: Invalid number of sections: %d\n",
 712                        __func__, num_sections);
 713                 ret = EFI_LOAD_ERROR;
 714                 goto err;
 715         }
 716
 717         /* Authenticate an image */
 718         if (efi_image_authenticate(efi, efi_size))
 719                 handle->auth_status = EFI_IMAGE_AUTH_PASSED;
 720         else
 721                 handle->auth_status = EFI_IMAGE_AUTH_FAILED;
 722
 723         /* Calculate upper virtual address boundary */
 724         for (i = num_sections - 1; i >= 0; i--) {
 725                 IMAGE_SECTION_HEADER *sec = &sections[i];
 726                 virt_size = max_t(unsigned long, virt_size,
 727                                   sec->VirtualAddress + sec->Misc.VirtualSize);
 728         }
 729
 730         /* Read 32/64bit specific header bits */
 731         if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 732                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 733                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 734                 image_base = opt->ImageBase;
 735                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 736                 handle->image_type = opt->Subsystem;
 737                 efi_reloc = efi_alloc(virt_size,
 738                                       loaded_image_info->image_code_type);
 739                 if (!efi_reloc) {
 740                         printf("%s: Could not allocate %lu bytes\n",
 741                                __func__, virt_size);
 742                         ret = EFI_OUT_OF_RESOURCES;
 743                         goto err;
 744                 }
 745                 handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 746                 rel_size = opt->DataDirectory[rel_idx].Size;
 747                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 748                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 749         } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 750                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 751                 image_base = opt->ImageBase;
 752                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 753                 handle->image_type = opt->Subsystem;
 754                 efi_reloc = efi_alloc(virt_size,
 755                                       loaded_image_info->image_code_type);
 756                 if (!efi_reloc) {
 757                         printf("%s: Could not allocate %lu bytes\n",
 758                                __func__, virt_size);
 759                         ret = EFI_OUT_OF_RESOURCES;
 760                         goto err;
 761                 }
 762                 handle->entry = efi_reloc + opt->AddressOfEntryPoint;
 763                 rel_size = opt->DataDirectory[rel_idx].Size;
 764                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 765                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 766         } else {
 767                 printf("%s: Invalid optional header magic %x\n", __func__,
 768                        nt->OptionalHeader.Magic);
 769                 ret = EFI_LOAD_ERROR;
 770                 goto err;
 771         }
 772
 773         /* Copy PE headers */
 774         memcpy(efi_reloc, efi,
 775                sizeof(*dos)
 776                  + sizeof(*nt)
 777                  + nt->FileHeader.SizeOfOptionalHeader
 778                  + num_sections * sizeof(IMAGE_SECTION_HEADER));
 779
 780         /* Load sections into RAM */
 781         for (i = num_sections - 1; i >= 0; i--) {
 782                 IMAGE_SECTION_HEADER *sec = &sections[i];
 783                 memset(efi_reloc + sec->VirtualAddress, 0,
 784                        sec->Misc.VirtualSize);
 785                 memcpy(efi_reloc + sec->VirtualAddress,
 786                        efi + sec->PointerToRawData,
 787                        sec->SizeOfRawData);
 788         }
 789
 790         /* Run through relocations */
 791         if (efi_loader_relocate(rel, rel_size, efi_reloc,
 792                                 (unsigned long)image_base) != EFI_SUCCESS) {
 793                 efi_free_pages((uintptr_t) efi_reloc,
 794                                (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 795                 ret = EFI_LOAD_ERROR;
 796                 goto err;
 797         }
 798
 799         /* Flush cache */
 800         flush_cache((ulong)efi_reloc,
 801                     ALIGN(virt_size, EFI_CACHELINE_SIZE));
 802         invalidate_icache_all();
 803
 804         /* Populate the loaded image interface bits */
 805         loaded_image_info->image_base = efi_reloc;
 806         loaded_image_info->image_size = virt_size;
 807
 808         if (handle->auth_status == EFI_IMAGE_AUTH_PASSED)
 809                 return EFI_SUCCESS;
 810         else
 811                 return EFI_SECURITY_VIOLATION;
 812
 813 err:
 814         return ret;
 815 }