lib/efi_loader/efi_image_loader.c

   1 /*
   2  *  EFI image loader
   3  *
   4  *  based partly on wine code
   5  *
   6  *  Copyright (c) 2016 Alexander Graf
   7  *
   8  *  SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #include <common.h>
  12 #include <efi_loader.h>
  13 #include <pe.h>
  14 #include <asm/global_data.h>
  15
  16 DECLARE_GLOBAL_DATA_PTR;
  17
  18 const efi_guid_t efi_guid_device_path = DEVICE_PATH_GUID;
  19 const efi_guid_t efi_guid_loaded_image = LOADED_IMAGE_GUID;
  20
  21 static efi_status_t efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
  22                         unsigned long rel_size, void *efi_reloc)
  23 {
  24         const IMAGE_BASE_RELOCATION *end;
  25         int i;
  26
  27         end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
  28         while (rel < end - 1 && rel->SizeOfBlock) {
  29                 const uint16_t *relocs = (const uint16_t *)(rel + 1);
  30                 i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
  31                 while (i--) {
  32                         uint32_t offset = (uint32_t)(*relocs & 0xfff) +
  33                                           rel->VirtualAddress;
  34                         int type = *relocs >> EFI_PAGE_SHIFT;
  35                         unsigned long delta = (unsigned long)efi_reloc;
  36                         uint64_t *x64 = efi_reloc + offset;
  37                         uint32_t *x32 = efi_reloc + offset;
  38                         uint16_t *x16 = efi_reloc + offset;
  39
  40                         switch (type) {
  41                         case IMAGE_REL_BASED_ABSOLUTE:
  42                                 break;
  43                         case IMAGE_REL_BASED_HIGH:
  44                                 *x16 += ((uint32_t)delta) >> 16;
  45                                 break;
  46                         case IMAGE_REL_BASED_LOW:
  47                                 *x16 += (uint16_t)delta;
  48                                 break;
  49                         case IMAGE_REL_BASED_HIGHLOW:
  50                                 *x32 += (uint32_t)delta;
  51                                 break;
  52                         case IMAGE_REL_BASED_DIR64:
  53                                 *x64 += (uint64_t)delta;
  54                                 break;
  55                         default:
  56                                 printf("Unknown Relocation off %x type %x\n",
  57                                        offset, type);
  58                                 return EFI_LOAD_ERROR;
  59                         }
  60                         relocs++;
  61                 }
  62                 rel = (const IMAGE_BASE_RELOCATION *)relocs;
  63         }
  64         return EFI_SUCCESS;
  65 }
  66
  67 void __weak invalidate_icache_all(void)
  68 {
  69         /* If the system doesn't support icache_all flush, cross our fingers */
  70 }
  71
  72 /*
  73  * This function loads all sections from a PE binary into a newly reserved
  74  * piece of memory. On successful load it then returns the entry point for
  75  * the binary. Otherwise NULL.
  76  */
  77 void *efi_load_pe(void *efi, struct efi_loaded_image *loaded_image_info)
  78 {
  79         IMAGE_NT_HEADERS32 *nt;
  80         IMAGE_DOS_HEADER *dos;
  81         IMAGE_SECTION_HEADER *sections;
  82         int num_sections;
  83         void *efi_reloc;
  84         int i;
  85         const IMAGE_BASE_RELOCATION *rel;
  86         unsigned long rel_size;
  87         int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
  88         void *entry;
  89         uint64_t image_size;
  90         unsigned long virt_size = 0;
  91         bool can_run_nt64 = true;
  92         bool can_run_nt32 = true;
  93
  94 #if defined(CONFIG_ARM64)
  95         can_run_nt32 = false;
  96 #elif defined(CONFIG_ARM)
  97         can_run_nt64 = false;
  98 #endif
  99
 100         dos = efi;
 101         if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 102                 printf("%s: Invalid DOS Signature\n", __func__);
 103                 return NULL;
 104         }
 105
 106         nt = (void *) ((char *)efi + dos->e_lfanew);
 107         if (nt->Signature != IMAGE_NT_SIGNATURE) {
 108                 printf("%s: Invalid NT Signature\n", __func__);
 109                 return NULL;
 110         }
 111
 112         /* Calculate upper virtual address boundary */
 113         num_sections = nt->FileHeader.NumberOfSections;
 114         sections = (void *)&nt->OptionalHeader +
 115                             nt->FileHeader.SizeOfOptionalHeader;
 116
 117         for (i = num_sections - 1; i >= 0; i--) {
 118                 IMAGE_SECTION_HEADER *sec = &sections[i];
 119                 virt_size = max_t(unsigned long, virt_size,
 120                                   sec->VirtualAddress + sec->Misc.VirtualSize);
 121         }
 122
 123         /* Read 32/64bit specific header bits */
 124         if (can_run_nt64 &&
 125             (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC)) {
 126                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 127                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 128                 image_size = opt->SizeOfImage;
 129                 efi_reloc = efi_alloc(virt_size, EFI_LOADER_DATA);
 130                 if (!efi_reloc) {
 131                         printf("%s: Could not allocate %ld bytes\n",
 132                                 __func__, virt_size);
 133                         return NULL;
 134                 }
 135                 entry = efi_reloc + opt->AddressOfEntryPoint;
 136                 rel_size = opt->DataDirectory[rel_idx].Size;
 137                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 138         } else if (can_run_nt32 &&
 139                    (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC)) {
 140                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 141                 image_size = opt->SizeOfImage;
 142                 efi_reloc = efi_alloc(virt_size, EFI_LOADER_DATA);
 143                 if (!efi_reloc) {
 144                         printf("%s: Could not allocate %ld bytes\n",
 145                                 __func__, virt_size);
 146                         return NULL;
 147                 }
 148                 entry = efi_reloc + opt->AddressOfEntryPoint;
 149                 rel_size = opt->DataDirectory[rel_idx].Size;
 150                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 151         } else {
 152                 printf("%s: Invalid optional header magic %x\n", __func__,
 153                        nt->OptionalHeader.Magic);
 154                 return NULL;
 155         }
 156
 157         /* Load sections into RAM */
 158         for (i = num_sections - 1; i >= 0; i--) {
 159                 IMAGE_SECTION_HEADER *sec = &sections[i];
 160                 memset(efi_reloc + sec->VirtualAddress, 0,
 161                        sec->Misc.VirtualSize);
 162                 memcpy(efi_reloc + sec->VirtualAddress,
 163                        efi + sec->PointerToRawData,
 164                        sec->SizeOfRawData);
 165         }
 166
 167         /* Run through relocations */
 168         if (efi_loader_relocate(rel, rel_size, efi_reloc) != EFI_SUCCESS) {
 169                 efi_free_pages((uintptr_t) efi_reloc,
 170                                (virt_size + EFI_PAGE_MASK) >> EFI_PAGE_SHIFT);
 171                 return NULL;
 172         }
 173
 174         /* Flush cache */
 175         flush_cache((ulong)efi_reloc,
 176                     ALIGN(virt_size, CONFIG_SYS_CACHELINE_SIZE));
 177         invalidate_icache_all();
 178
 179         /* Populate the loaded image interface bits */
 180         loaded_image_info->image_base = efi;
 181         loaded_image_info->image_size = image_size;
 182
 183         return entry;
 184 }