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 efi_status_t EFIAPI efi_return_handle(void *handle, efi_guid_t *protocol,
  22                         void **protocol_interface, void *agent_handle,
  23                         void *controller_handle, uint32_t attributes)
  24 {
  25         *protocol_interface = handle;
  26         return EFI_SUCCESS;
  27 }
  28
  29 static void efi_loader_relocate(const IMAGE_BASE_RELOCATION *rel,
  30                         unsigned long rel_size, void *efi_reloc)
  31 {
  32         const IMAGE_BASE_RELOCATION *end;
  33         int i;
  34
  35         end = (const IMAGE_BASE_RELOCATION *)((const char *)rel + rel_size);
  36         while (rel < end - 1 && rel->SizeOfBlock) {
  37                 const uint16_t *relocs = (const uint16_t *)(rel + 1);
  38                 i = (rel->SizeOfBlock - sizeof(*rel)) / sizeof(uint16_t);
  39                 while (i--) {
  40                         uint32_t offset = (uint32_t)(*relocs & 0xfff) +
  41                                           rel->VirtualAddress;
  42                         int type = *relocs >> EFI_PAGE_SHIFT;
  43                         unsigned long delta = (unsigned long)efi_reloc;
  44                         uint64_t *x64 = efi_reloc + offset;
  45                         uint32_t *x32 = efi_reloc + offset;
  46                         uint16_t *x16 = efi_reloc + offset;
  47
  48                         switch (type) {
  49                         case IMAGE_REL_BASED_ABSOLUTE:
  50                                 break;
  51                         case IMAGE_REL_BASED_HIGH:
  52                                 *x16 += ((uint32_t)delta) >> 16;
  53                                 break;
  54                         case IMAGE_REL_BASED_LOW:
  55                                 *x16 += (uint16_t)delta;
  56                                 break;
  57                         case IMAGE_REL_BASED_HIGHLOW:
  58                                 *x32 += (uint32_t)delta;
  59                                 break;
  60                         case IMAGE_REL_BASED_DIR64:
  61                                 *x64 += (uint64_t)delta;
  62                                 break;
  63                         default:
  64                                 printf("Unknown Relocation off %x type %x\n",
  65                                        offset, type);
  66                         }
  67                         relocs++;
  68                 }
  69                 rel = (const IMAGE_BASE_RELOCATION *)relocs;
  70         }
  71 }
  72
  73 void __weak invalidate_icache_all(void)
  74 {
  75         /* If the system doesn't support icache_all flush, cross our fingers */
  76 }
  77
  78 /*
  79  * This function loads all sections from a PE binary into a newly reserved
  80  * piece of memory. On successful load it then returns the entry point for
  81  * the binary. Otherwise NULL.
  82  */
  83 void *efi_load_pe(void *efi, struct efi_loaded_image *loaded_image_info)
  84 {
  85         IMAGE_NT_HEADERS32 *nt;
  86         IMAGE_DOS_HEADER *dos;
  87         IMAGE_SECTION_HEADER *sections;
  88         int num_sections;
  89         void *efi_reloc;
  90         int i;
  91         const IMAGE_BASE_RELOCATION *rel;
  92         unsigned long rel_size;
  93         int rel_idx = IMAGE_DIRECTORY_ENTRY_BASERELOC;
  94         void *entry;
  95         uint64_t image_size;
  96         unsigned long virt_size = 0;
  97         bool can_run_nt64 = true;
  98         bool can_run_nt32 = true;
  99
 100 #if defined(CONFIG_ARM64)
 101         can_run_nt32 = false;
 102 #elif defined(CONFIG_ARM)
 103         can_run_nt64 = false;
 104 #endif
 105
 106         dos = efi;
 107         if (dos->e_magic != IMAGE_DOS_SIGNATURE) {
 108                 printf("%s: Invalid DOS Signature\n", __func__);
 109                 return NULL;
 110         }
 111
 112         nt = (void *) ((char *)efi + dos->e_lfanew);
 113         if (nt->Signature != IMAGE_NT_SIGNATURE) {
 114                 printf("%s: Invalid NT Signature\n", __func__);
 115                 return NULL;
 116         }
 117
 118         /* Calculate upper virtual address boundary */
 119         num_sections = nt->FileHeader.NumberOfSections;
 120         sections = (void *)&nt->OptionalHeader +
 121                             nt->FileHeader.SizeOfOptionalHeader;
 122
 123         for (i = num_sections - 1; i >= 0; i--) {
 124                 IMAGE_SECTION_HEADER *sec = &sections[i];
 125                 virt_size = max_t(unsigned long, virt_size,
 126                                   sec->VirtualAddress + sec->Misc.VirtualSize);
 127         }
 128
 129         /* Read 32/64bit specific header bits */
 130         if (can_run_nt64 &&
 131             (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR64_MAGIC)) {
 132                 IMAGE_NT_HEADERS64 *nt64 = (void *)nt;
 133                 IMAGE_OPTIONAL_HEADER64 *opt = &nt64->OptionalHeader;
 134                 image_size = opt->SizeOfImage;
 135                 efi_reloc = efi_alloc(virt_size, EFI_LOADER_DATA);
 136                 if (!efi_reloc) {
 137                         printf("%s: Could not allocate %ld bytes\n",
 138                                 __func__, virt_size);
 139                         return NULL;
 140                 }
 141                 entry = efi_reloc + opt->AddressOfEntryPoint;
 142                 rel_size = opt->DataDirectory[rel_idx].Size;
 143                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 144         } else if (can_run_nt32 &&
 145                    (nt->OptionalHeader.Magic == IMAGE_NT_OPTIONAL_HDR32_MAGIC)) {
 146                 IMAGE_OPTIONAL_HEADER32 *opt = &nt->OptionalHeader;
 147                 image_size = opt->SizeOfImage;
 148                 efi_reloc = efi_alloc(virt_size, EFI_LOADER_DATA);
 149                 if (!efi_reloc) {
 150                         printf("%s: Could not allocate %ld bytes\n",
 151                                 __func__, virt_size);
 152                         return NULL;
 153                 }
 154                 entry = efi_reloc + opt->AddressOfEntryPoint;
 155                 rel_size = opt->DataDirectory[rel_idx].Size;
 156                 rel = efi_reloc + opt->DataDirectory[rel_idx].VirtualAddress;
 157         } else {
 158                 printf("%s: Invalid optional header magic %x\n", __func__,
 159                        nt->OptionalHeader.Magic);
 160                 return NULL;
 161         }
 162
 163         /* Load sections into RAM */
 164         for (i = num_sections - 1; i >= 0; i--) {
 165                 IMAGE_SECTION_HEADER *sec = &sections[i];
 166                 memset(efi_reloc + sec->VirtualAddress, 0,
 167                        sec->Misc.VirtualSize);
 168                 memcpy(efi_reloc + sec->VirtualAddress,
 169                        efi + sec->PointerToRawData,
 170                        sec->SizeOfRawData);
 171         }
 172
 173         /* Run through relocations */
 174         efi_loader_relocate(rel, rel_size, efi_reloc);
 175
 176         /* Flush cache */
 177         flush_cache((ulong)efi_reloc, virt_size);
 178         invalidate_icache_all();
 179
 180         /* Populate the loaded image interface bits */
 181         loaded_image_info->image_base = efi;
 182         loaded_image_info->image_size = image_size;
 183
 184         return entry;
 185 }