src/sd-boot/pefile.c

   1 /*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
   2
   3 /*
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU Lesser General Public License as published by
   6  * the Free Software Foundation; either version 2.1 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * Copyright (C) 2015 Kay Sievers <kay@vrfy.org>
  15  */
  16
  17 #include <efi.h>
  18 #include <efilib.h>
  19
  20 #include "util.h"
  21 #include "pefile.h"
  22
  23 struct DosFileHeader {
  24         UINT8   Magic[2];
  25         UINT16  LastSize;
  26         UINT16  nBlocks;
  27         UINT16  nReloc;
  28         UINT16  HdrSize;
  29         UINT16  MinAlloc;
  30         UINT16  MaxAlloc;
  31         UINT16  ss;
  32         UINT16  sp;
  33         UINT16  Checksum;
  34         UINT16  ip;
  35         UINT16  cs;
  36         UINT16  RelocPos;
  37         UINT16  nOverlay;
  38         UINT16  reserved[4];
  39         UINT16  OEMId;
  40         UINT16  OEMInfo;
  41         UINT16  reserved2[10];
  42         UINT32  ExeHeader;
  43 } __attribute__((packed));
  44
  45 #define PE_HEADER_MACHINE_I386          0x014c
  46 #define PE_HEADER_MACHINE_X64           0x8664
  47 struct PeFileHeader {
  48         UINT16  Machine;
  49         UINT16  NumberOfSections;
  50         UINT32  TimeDateStamp;
  51         UINT32  PointerToSymbolTable;
  52         UINT32  NumberOfSymbols;
  53         UINT16  SizeOfOptionalHeader;
  54         UINT16  Characteristics;
  55 } __attribute__((packed));
  56
  57 struct PeSectionHeader {
  58         UINT8   Name[8];
  59         UINT32  VirtualSize;
  60         UINT32  VirtualAddress;
  61         UINT32  SizeOfRawData;
  62         UINT32  PointerToRawData;
  63         UINT32  PointerToRelocations;
  64         UINT32  PointerToLinenumbers;
  65         UINT16  NumberOfRelocations;
  66         UINT16  NumberOfLinenumbers;
  67         UINT32  Characteristics;
  68 } __attribute__((packed));
  69
  70
  71 EFI_STATUS pefile_locate_sections(EFI_FILE *dir, CHAR16 *path, CHAR8 **sections, UINTN *addrs, UINTN *offsets, UINTN *sizes) {
  72         EFI_FILE_HANDLE handle;
  73         struct DosFileHeader dos;
  74         uint8_t magic[4];
  75         struct PeFileHeader pe;
  76         UINTN len;
  77         UINTN i;
  78         EFI_STATUS err;
  79
  80         err = uefi_call_wrapper(dir->Open, 5, dir, &handle, path, EFI_FILE_MODE_READ, 0ULL);
  81         if (EFI_ERROR(err))
  82                 return err;
  83
  84         /* MS-DOS stub */
  85         len = sizeof(dos);
  86         err = uefi_call_wrapper(handle->Read, 3, handle, &len, &dos);
  87         if (EFI_ERROR(err))
  88                 goto out;
  89         if (len != sizeof(dos)) {
  90                 err = EFI_LOAD_ERROR;
  91                 goto out;
  92         }
  93
  94         if (CompareMem(dos.Magic, "MZ", 2) != 0) {
  95                 err = EFI_LOAD_ERROR;
  96                 goto out;
  97         }
  98
  99         err = uefi_call_wrapper(handle->SetPosition, 2, handle, dos.ExeHeader);
 100         if (EFI_ERROR(err))
 101                 goto out;
 102
 103         /* PE header */
 104         len = sizeof(magic);
 105         err = uefi_call_wrapper(handle->Read, 3, handle, &len, &magic);
 106         if (EFI_ERROR(err))
 107                 goto out;
 108         if (len != sizeof(magic)) {
 109                 err = EFI_LOAD_ERROR;
 110                 goto out;
 111         }
 112
 113         if (CompareMem(magic, "PE\0\0", 2) != 0) {
 114                 err = EFI_LOAD_ERROR;
 115                 goto out;
 116         }
 117
 118         len = sizeof(pe);
 119         err = uefi_call_wrapper(handle->Read, 3, handle, &len, &pe);
 120         if (EFI_ERROR(err))
 121                 goto out;
 122         if (len != sizeof(pe)) {
 123                 err = EFI_LOAD_ERROR;
 124                 goto out;
 125         }
 126
 127         /* PE32+ Subsystem type */
 128         if (pe.Machine != PE_HEADER_MACHINE_X64 &&
 129             pe.Machine != PE_HEADER_MACHINE_I386) {
 130                 err = EFI_LOAD_ERROR;
 131                 goto out;
 132         }
 133
 134         if (pe.NumberOfSections > 96) {
 135                 err = EFI_LOAD_ERROR;
 136                 goto out;
 137         }
 138
 139         /* the sections start directly after the headers */
 140         err = uefi_call_wrapper(handle->SetPosition, 2, handle, dos.ExeHeader + sizeof(magic) + sizeof(pe) + pe.SizeOfOptionalHeader);
 141         if (EFI_ERROR(err))
 142                 goto out;
 143
 144         for (i = 0; i < pe.NumberOfSections; i++) {
 145                 struct PeSectionHeader sect;
 146                 UINTN j;
 147
 148                 len = sizeof(sect);
 149                 err = uefi_call_wrapper(handle->Read, 3, handle, &len, &sect);
 150                 if (EFI_ERROR(err))
 151                         goto out;
 152                 if (len != sizeof(sect)) {
 153                         err = EFI_LOAD_ERROR;
 154                         goto out;
 155                 }
 156                 for (j = 0; sections[j]; j++) {
 157                         if (CompareMem(sect.Name, sections[j], strlena(sections[j])) != 0)
 158                                 continue;
 159
 160                         if (addrs)
 161                                 addrs[j] = (UINTN)sect.VirtualAddress;
 162                         if (offsets)
 163                                 offsets[j] = (UINTN)sect.PointerToRawData;
 164                         if (sizes)
 165                                 sizes[j] = (UINTN)sect.VirtualSize;
 166                 }
 167         }
 168
 169 out:
 170         uefi_call_wrapper(handle->Close, 1, handle);
 171         return err;
 172 }