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 <efi_loader.h>
  12 #include <pe.h>
  13
  14 const efi_guid_t efi_global_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
  15 const efi_guid_t efi_guid_device_path = DEVICE_PATH_GUID;
  16 const efi_guid_t efi_guid_loaded_image = LOADED_IMAGE_GUID;
  17 const efi_guid_t efi_simple_file_system_protocol_guid =
  18                 EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID;
  19 const efi_guid_t efi_file_info_guid = EFI_FILE_INFO_GUID;
  20
  21 static int machines[] = {
  22 #if defined(CONFIG_ARM64)
  23         IMAGE_FILE_MACHINE_ARM64,
  24 #elif defined(CONFIG_ARM)
  25         IMAGE_FILE_MACHINE_ARM,
  26         IMAGE_FILE_MACHINE_THUMB,
  27         IMAGE_FILE_MACHINE_ARMNT,
  28 #endif
  29
  30 #if defined(CONFIG_X86_64)
  31         IMAGE_FILE_MACHINE_AMD64,
  32 #elif defined(CONFIG_X86)
  33         IMAGE_FILE_MACHINE_I386,
  34 #endif
  35
  36 #if defined(CONFIG_CPU_RISCV_32)
  37         IMAGE_FILE_MACHINE_RISCV32,
  38 #endif
  39
  40 #if defined(CONFIG_CPU_RISCV_64)
  41         IMAGE_FILE_MACHINE_RISCV64,
  42 #endif
  43         0 };
  44
  45 /*
  46  * Print information about a loaded image.
  47  *
  48  * If the program counter is located within the image the offset to the base
  49  * address is shown.
  50  *
  51  * @image:      loaded image
  52  * @pc:         program counter (use NULL to suppress offset output)
  53  * @return:     status code
  54  */
  55 efi_status_t efi_print_image_info(struct efi_loaded_image *image, void *pc)
  56 {
  57         if (!image)
  58                 return EFI_INVALID_PARAMETER;
  59         printf("UEFI image");
  60         printf(" [0x%p:0x%p]",
  61                image->reloc_base, image->reloc_base + image->reloc_size - 1);
  62         if (pc && pc >= image->reloc_base &&
  63             pc < image->reloc_base + image->reloc_size)
  64                 printf(" pc=0x%zx", pc - image->reloc_base);
  65         if (image->file_path)
  66                 printf(" '%pD'", image->file_path);
  67         printf("\n");
  68         return EFI_SUCCESS;
  69 }
  70
  71 /*
  72  * Print information about all loaded images.
  73  *
  74  * @pc:         program counter (use NULL to suppress offset output)
  75  */
  76 void efi_print_image_infos(void *pc)
  77 {
  78         struct efi_object *efiobj;
  79         struct efi_handler *handler;
  80
  81         list_for_each_entry(efiobj, &efi_obj_list, link) {
  82                 list_for_each_entry(handler, &efiobj->protocols, link) {
  83                         if (!guidcmp(handler->guid, &efi_guid_loaded_image)) {
  84                                 efi_print_image_info(
  85                                         handler->protocol_interface, pc);
  86                         }
  87                 }
  88         }
  89 }
  90
  91 static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
  92                         unsigned long rel_size, void *efi_reloc,
  93                         unsigned long pref_address)
  94 {
  95         unsigned long delta = (unsigned long)efi_reloc - pref_address;
  96         const IMAGE_BASE_RELOCATION *end;
  97         int i;
  98
  99         if (delta == 0)
 100                 return EFI_SUCCESS;
 101
 102         end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
 103         while (rel < end - 1 && rel->SizeOfBlock) {
 104                 const uint16_t *relocs = (const uint16_t *)(rel + 1);
 105                 i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
 106                 while (i--) {
 107                         uint32_t offset = (uint32_t)(*relocs & 0xfff) +
 108                                           rel->VirtualAddress;
 109                         int type = *relocs >> EFI_PAGE_SHIFT;
 110                         uint64_t *x64 = efi_reloc + offset;
 111                         uint32_t *x32 = efi_reloc + offset;
 112                         uint16_t *x16 = efi_reloc + offset;
 113
 114                         switch (type) {
 115                         case IMAGE_REL_BASED_ABSOLUTE:
 116                                 break;
 117                         case IMAGE_REL_BASED_HIGH:
 118                                 *x16 += ((uint32_t)delta) >> 16;
 119                                 break;
 120                         case IMAGE_REL_BASED_LOW:
 121                                 *x16 += (uint16_t)delta;
 122                                 break;
 123                         case IMAGE_REL_BASED_HIGHLOW:
 124                                 *x32 += (uint32_t)delta;
 125                                 break;
 126                         case IMAGE_REL_BASED_DIR64:
 127                                 *x64 += (uint64_t)delta;
 128                                 break;
 129 #ifdef __riscv
 130                         case IMAGE_REL_BASED_RISCV_HI20:
 131                                 *x32 = ((*x32 & 0xfffff000) + (uint32_t)delta) |
 132                                         (*x32 & 0x00000fff);
 133                                 break;
 134                         case IMAGE_REL_BASED_RISCV_LOW12I:
 135                         case IMAGE_REL_BASED_RISCV_LOW12S:
 136                                 /* We know that we're 4k aligned */
 137                                 if (delta & 0xfff) {
 138                                         printf("Unsupported reloc offset\n");
 139                                         return EFI_LOAD_ERROR;
 140                                 }
 141                                 break;
 142 #endif
 143                         default:
 144                                 printf("Unknown Relocation off %x type %x\n",
 145                                        offset, type);
 146                                 return EFI_LOAD_ERROR;
 147                         }
 148                         relocs++;
 149                 }
 150                 rel = (const IMAGE_BASE_RELOCATION *)relocs;
 151         }
 152         return EFI_SUCCESS;
 153 }
 154
 155 void __weak invalidate_icache_all(void)
 156 {
 157         /* If the system doesn't support icache_all flush, cross our fingers */
 158 }
 159
 160 /*
 161  * Determine the memory types to be used for code and data.
 162  *
 163  * @loaded_image_info   image descriptor
 164  * @image_type          field Subsystem of the optional header for
 165  *                      Windows specific field
 166  */
 167 static void efi_set_code_and_data_type(
 168                         struct efi_loaded_image *loaded_image_info,
 169                         uint16_t image_type)
 170 {
 171         switch (image_type) {
 172         case IMAGE_SUBSYSTEM_EFI_APPLICATION:
 173                 loaded_image_info->image_code_type = EFI_LOADER_CODE;
 174                 loaded_image_info->image_data_type = EFI_LOADER_DATA;
 175                 break;
 176         case IMAGE_SUBSYSTEM_EFI_BOOT_SERVICE_DRIVER:
 177                 loaded_image_info->image_code_type = EFI_BOOT_SERVICES_CODE;
 178                 loaded_image_info->image_data_type = EFI_BOOT_SERVICES_DATA;
 179                 break;
 180         case IMAGE_SUBSYSTEM_EFI_RUNTIME_DRIVER:
 181         case IMAGE_SUBSYSTEM_EFI_ROM:
 182                 loaded_image_info->image_code_type = EFI_RUNTIME_SERVICES_CODE;
 183                 loaded_image_info->image_data_type = EFI_RUNTIME_SERVICES_DATA;
 184                 break;
 185         default:
 186                 printf("%s: invalid image type: %u\n", __func__, image_type);
 187                 /* Let's assume it is an application */
 188                 loaded_image_info->image_code_type = EFI_LOADER_CODE;
 189                 loaded_image_info->image_data_type = EFI_LOADER_DATA;
 190                 break;
 191         }
 192 }
 193
 194 /*
 195  * This function loads all sections from a PE binary into a newly reserved
 196  * piece of memory. On successful load it then returns the entry point for
 197  * the binary. Otherwise NULL.
 198  */
 199 void *efi_load_pe(void *efi, struct efi_loaded_image *loaded_image_info)
 200 {
 201         IMAGE_NT_HEADERS32 *nt;
 202         IMAGE_DOS_HEADER *dos;
 203         IMAGE_SECTION_HEADER *sections;
 204         int num_sections;
 205         void *efi_reloc;
 206         int i;
 207         const IMAGE_BASE_RELOCATION *rel;
 208         unsigned long rel_size;
 209         int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
 210         void *entry;
 211         uint64_t image_base;
 212         uint64_t image_size;
 213         unsigned long virt_size = 0;
 214         int supported = 0;
 215
 216         dos = efi;
 217         if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 218                 printf("%s: Invalid DOS Signature\n", __func__);
 219                 return NULL;
 220         }
 221
 222         nt = (void *) ((char *)efi + dos->e_lfanew);
 223         if (nt->Signature != IMAGE_NT_SIGNATURE) {
 224                 printf("%s: Invalid NT Signature\n", __func__);
 225                 return NULL;
 226         }
 227
 228         for (i = 0; machines[i]; i++)
 229                 if (machines[i] == nt->FileHeader.Machine) {
 230                         supported = 1;
 231                         break;
 232                 }
 233
 234         if (!supported) {
 235                 printf("%s: Machine type 0x%04x is not supported\n",
 236                        __func__, nt->FileHeader.Machine);
 237                 return NULL;
 238         }
 239
 240         /* Calculate upper virtual address boundary */
 241         num_sections = nt->FileHeader.NumberOfSections;
 242         sections = (void *)&nt->OptionalHeader +
 243                             nt->FileHeader.SizeOfOptionalHeader;
 244
 245         for (i = num_sections - 1; i >= 0; i--) {
 246                 IMAGE_SECTION_HEADER *sec = &sections[i];
 247                 virt_size = max_t(unsigned long, virt_size,
 248                                   sec->VirtualAddress + sec->Misc.VirtualSize);
 249         }
 250
 251         /* Read 32/64bit specific header bits */
 252         if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC) {
 253                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 254                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 255                 image_base = opt->ImageBase;
 256                 image_size = opt->SizeOfImage;
 257                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 258                 efi_reloc = efi_alloc(virt_size,
 259                                       loaded_image_info->image_code_type);
 260                 if (!efi_reloc) {
 261                         printf("%s: Could not allocate %lu bytes\n",
 262                                __func__, virt_size);
 263                         return NULL;
 264                 }
 265                 entry = efi_reloc + opt->AddressOfEntryPoint;
 266                 rel_size = opt->DataDirectory[rel_idx].Size;
 267                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 268                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 269         } else if (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC) {
 270                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 271                 image_base = opt->ImageBase;
 272                 image_size = opt->SizeOfImage;
 273                 efi_set_code_and_data_type(loaded_image_info, opt->Subsystem);
 274                 efi_reloc = efi_alloc(virt_size,
 275                                       loaded_image_info->image_code_type);
 276                 if (!efi_reloc) {
 277                         printf("%s: Could not allocate %lu bytes\n",
 278                                __func__, virt_size);
 279                         return NULL;
 280                 }
 281                 entry = efi_reloc + opt->AddressOfEntryPoint;
 282                 rel_size = opt->DataDirectory[rel_idx].Size;
 283                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 284                 virt_size = ALIGN(virt_size, opt->SectionAlignment);
 285         } else {
 286                 printf("%s: Invalid optional header magic %x\n", __func__,
 287                        nt->OptionalHeader.Magic);
 288                 return NULL;
 289         }
 290
 291         /* Load sections into RAM */
 292         for (i = num_sections - 1; i >= 0; i--) {
 293                 IMAGE_SECTION_HEADER *sec = &sections[i];
 294                 memset(efi_reloc + sec->VirtualAddress, 0,
 295                        sec->Misc.VirtualSize);
 296                 memcpy(efi_reloc + sec->VirtualAddress,
 297                        efi + sec->PointerToRawData,
 298                        sec->SizeOfRawData);
 299         }
 300
 301         /* Run through relocations */
 302         if (efi_loader_relocate(rel, rel_size, efi_reloc,
 303                                 (unsigned long)image_base) != EFI_SUCCESS) {
 304                 efi_free_pages((uintptr_t) efi_reloc,
 305                                (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 306                 return NULL;
 307         }
 308
 309         /* Flush cache */
 310         flush_cache((ulong)efi_reloc,
 311                     ALIGN(virt_size, EFI_CACHELINE_SIZE));
 312         invalidate_icache_all();
 313
 314         /* Populate the loaded image interface bits */
 315         loaded_image_info->image_base = efi;
 316         loaded_image_info->image_size = image_size;
 317         loaded_image_info->reloc_base = efi_reloc;
 318         loaded_image_info->reloc_size = virt_size;
 319
 320         return entry;
 321 }