debug/pe: add optional header to File

This information is required by cmd/nm
to calculate absolute symbol addresses.

Update #6936
Update #7738

LGTM=rsc
R=golang-codereviews, bradfitz, gobot, rsc
CC=golang-codereviews
https://golang.org/cl/87500043

src/pkg/debug/pe/file.go

@@ -13,13 +13,15 @@ import (
 	"io"
 	"os"
 	"strconv"
+	"unsafe"
 )
 
 // A File represents an open PE file.
 type File struct {
 	FileHeader
-	Sections []*Section
+	OptionalHeader interface{} // of type *OptionalHeader32 or *OptionalHeader64
-	Symbols  []*Symbol
+	Sections       []*Section
+	Symbols        []*Symbol
 
 	closer io.Closer
 }
@@ -196,10 +198,33 @@ func NewFile(r io.ReaderAt) (*File, error) {
 		}
 	}
 
-	// Process sections.
+	// Read optional header.
 	sr.Seek(base, os.SEEK_SET)
-	binary.Read(sr, binary.LittleEndian, &f.FileHeader)
+	if err := binary.Read(sr, binary.LittleEndian, &f.FileHeader); err != nil {
-	sr.Seek(int64(f.FileHeader.SizeOfOptionalHeader), os.SEEK_CUR) //Skip OptionalHeader
+		return nil, err
+	}
+	var oh32 OptionalHeader32
+	var oh64 OptionalHeader64
+	switch uintptr(f.FileHeader.SizeOfOptionalHeader) {
+	case unsafe.Sizeof(oh32):
+		if err := binary.Read(sr, binary.LittleEndian, &oh32); err != nil {
+			return nil, err
+		}
+		if oh32.Magic != 0x10b { // PE32
+			return nil, fmt.Errorf("pe32 optional header has unexpected Magic of 0x%x", oh32.Magic)
+		}
+		f.OptionalHeader = &oh32
+	case unsafe.Sizeof(oh64):
+		if err := binary.Read(sr, binary.LittleEndian, &oh64); err != nil {
+			return nil, err
+		}
+		if oh64.Magic != 0x20b { // PE32+
+			return nil, fmt.Errorf("pe32+ optional header has unexpected Magic of 0x%x", oh64.Magic)
+		}
+		f.OptionalHeader = &oh64
+	}
+
+	// Process sections.
 	f.Sections = make([]*Section, f.FileHeader.NumberOfSections)
 	for i := 0; i < int(f.FileHeader.NumberOfSections); i++ {
 		sh := new(SectionHeader32)

src/pkg/debug/pe/file_test.go

@@ -12,6 +12,7 @@ import (
 type fileTest struct {
 	file     string
 	hdr      FileHeader
+	opthdr   interface{}
 	sections []*SectionHeader
 	symbols  []*Symbol
 }
@@ -20,6 +21,7 @@ var fileTests = []fileTest{
 	{
 		"testdata/gcc-386-mingw-obj",
 		FileHeader{0x014c, 0x000c, 0x0, 0x64a, 0x1e, 0x0, 0x104},
+		nil,
 		[]*SectionHeader{
 			{".text", 0, 0, 36, 500, 1440, 0, 3, 0, 0x60300020},
 			{".data", 0, 0, 0, 0, 0, 0, 0, 0, 3224371264},
@@ -56,25 +58,128 @@ var fileTests = []fileTest{
 	{
 		"testdata/gcc-386-mingw-exec",
 		FileHeader{0x014c, 0x000f, 0x4c6a1b60, 0x3c00, 0x282, 0xe0, 0x107},
+		&OptionalHeader32{
+			0x10b, 0x2, 0x38, 0xe00, 0x1a00, 0x200, 0x1160, 0x1000, 0x2000, 0x400000, 0x1000, 0x200, 0x4, 0x0, 0x1, 0x0, 0x4, 0x0, 0x0, 0x10000, 0x400, 0x14abb, 0x3, 0x0, 0x200000, 0x1000, 0x100000, 0x1000, 0x0, 0x10,
+			[16]DataDirectory{
+				{0x0, 0x0},
+				{0x5000, 0x3c8},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x7000, 0x18},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+			},
+		},
 		[]*SectionHeader{
-			{Name: ".text", VirtualSize: 0xcd8, VirtualAddress: 0x1000, Size: 0xe00, Offset: 0x400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x60500060},
+			{".text", 0xcd8, 0x1000, 0xe00, 0x400, 0x0, 0x0, 0x0, 0x0, 0x60500060},
-			{Name: ".data", VirtualSize: 0x10, VirtualAddress: 0x2000, Size: 0x200, Offset: 0x1200, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0300040},
+			{".data", 0x10, 0x2000, 0x200, 0x1200, 0x0, 0x0, 0x0, 0x0, 0xc0300040},
-			{Name: ".rdata", VirtualSize: 0x120, VirtualAddress: 0x3000, Size: 0x200, Offset: 0x1400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x40300040},
+			{".rdata", 0x120, 0x3000, 0x200, 0x1400, 0x0, 0x0, 0x0, 0x0, 0x40300040},
-			{Name: ".bss", VirtualSize: 0xdc, VirtualAddress: 0x4000, Size: 0x0, Offset: 0x0, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0400080},
+			{".bss", 0xdc, 0x4000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc0400080},
-			{Name: ".idata", VirtualSize: 0x3c8, VirtualAddress: 0x5000, Size: 0x400, Offset: 0x1600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0300040},
+			{".idata", 0x3c8, 0x5000, 0x400, 0x1600, 0x0, 0x0, 0x0, 0x0, 0xc0300040},
-			{Name: ".CRT", VirtualSize: 0x18, VirtualAddress: 0x6000, Size: 0x200, Offset: 0x1a00, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0300040},
+			{".CRT", 0x18, 0x6000, 0x200, 0x1a00, 0x0, 0x0, 0x0, 0x0, 0xc0300040},
-			{Name: ".tls", VirtualSize: 0x20, VirtualAddress: 0x7000, Size: 0x200, Offset: 0x1c00, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0xc0300040},
+			{".tls", 0x20, 0x7000, 0x200, 0x1c00, 0x0, 0x0, 0x0, 0x0, 0xc0300040},
-			{Name: ".debug_aranges", VirtualSize: 0x20, VirtualAddress: 0x8000, Size: 0x200, Offset: 0x1e00, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_aranges", 0x20, 0x8000, 0x200, 0x1e00, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_pubnames", VirtualSize: 0x51, VirtualAddress: 0x9000, Size: 0x200, Offset: 0x2000, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_pubnames", 0x51, 0x9000, 0x200, 0x2000, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_pubtypes", VirtualSize: 0x91, VirtualAddress: 0xa000, Size: 0x200, Offset: 0x2200, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_pubtypes", 0x91, 0xa000, 0x200, 0x2200, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_info", VirtualSize: 0xe22, VirtualAddress: 0xb000, Size: 0x1000, Offset: 0x2400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_info", 0xe22, 0xb000, 0x1000, 0x2400, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_abbrev", VirtualSize: 0x157, VirtualAddress: 0xc000, Size: 0x200, Offset: 0x3400, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_abbrev", 0x157, 0xc000, 0x200, 0x3400, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_line", VirtualSize: 0x144, VirtualAddress: 0xd000, Size: 0x200, Offset: 0x3600, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_line", 0x144, 0xd000, 0x200, 0x3600, 0x0, 0x0, 0x0, 0x0, 0x42100000},
-			{Name: ".debug_frame", VirtualSize: 0x34, VirtualAddress: 0xe000, Size: 0x200, Offset: 0x3800, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42300000},
+			{".debug_frame", 0x34, 0xe000, 0x200, 0x3800, 0x0, 0x0, 0x0, 0x0, 0x42300000},
-			{Name: ".debug_loc", VirtualSize: 0x38, VirtualAddress: 0xf000, Size: 0x200, Offset: 0x3a00, PointerToRelocations: 0x0, PointerToLineNumbers: 0x0, NumberOfRelocations: 0x0, NumberOfLineNumbers: 0x0, Characteristics: 0x42100000},
+			{".debug_loc", 0x38, 0xf000, 0x200, 0x3a00, 0x0, 0x0, 0x0, 0x0, 0x42100000},
 		},
 		[]*Symbol{},
 	},
+	{
+		"testdata/gcc-amd64-mingw-obj",
+		FileHeader{0x8664, 0x6, 0x0, 0x198, 0x12, 0x0, 0x4},
+		nil,
+		[]*SectionHeader{
+			{".text", 0x0, 0x0, 0x30, 0x104, 0x15c, 0x0, 0x3, 0x0, 0x60500020},
+			{".data", 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc0500040},
+			{".bss", 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc0500080},
+			{".rdata", 0x0, 0x0, 0x10, 0x134, 0x0, 0x0, 0x0, 0x0, 0x40500040},
+			{".xdata", 0x0, 0x0, 0xc, 0x144, 0x0, 0x0, 0x0, 0x0, 0x40300040},
+			{".pdata", 0x0, 0x0, 0xc, 0x150, 0x17a, 0x0, 0x3, 0x0, 0x40300040},
+		},
+		[]*Symbol{
+			{".file", 0x0, -2, 0x0, 0x67},
+			{"main", 0x0, 1, 0x20, 0x2},
+			{".text", 0x0, 1, 0x0, 0x3},
+			{".data", 0x0, 2, 0x0, 0x3},
+			{".bss", 0x0, 3, 0x0, 0x3},
+			{".rdata", 0x0, 4, 0x0, 0x3},
+			{".xdata", 0x0, 5, 0x0, 0x3},
+			{".pdata", 0x0, 6, 0x0, 0x3},
+			{"__main", 0x0, 0, 0x20, 0x2},
+			{"puts", 0x0, 0, 0x20, 0x2},
+		},
+	},
+	{
+		"testdata/gcc-amd64-mingw-exec",
+		FileHeader{0x8664, 0x9, 0x53472993, 0x0, 0x0, 0xf0, 0x22f},
+		&OptionalHeader64{
+			0x20b, 0x2, 0x16, 0x6a00, 0x2400, 0x1600, 0x14e0, 0x1000, 0x400000, 0x1000, 0x200, 0x4, 0x0, 0x0, 0x0, 0x5, 0x2, 0x0, 0x11000, 0x400, 0x1841e, 0x3, 0x0, 0x200000, 0x1000, 0x100000, 0x1000, 0x0, 0x10,
+			[16]DataDirectory{
+				{0x0, 0x0},
+				{0xe000, 0x990},
+				{0x0, 0x0},
+				{0xa000, 0x498},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x10000, 0x28},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0xe254, 0x218},
+				{0x0, 0x0},
+				{0x0, 0x0},
+				{0x0, 0x0},
+			},
+		},
+		[]*SectionHeader{
+			{".text", 0x6860, 0x1000, 0x6a00, 0x400, 0x0, 0x0, 0x0, 0x0, 0x60500020},
+			{".data", 0xe0, 0x8000, 0x200, 0x6e00, 0x0, 0x0, 0x0, 0x0, 0xc0500040},
+			{".rdata", 0x6b0, 0x9000, 0x800, 0x7000, 0x0, 0x0, 0x0, 0x0, 0x40600040},
+			{".pdata", 0x498, 0xa000, 0x600, 0x7800, 0x0, 0x0, 0x0, 0x0, 0x40300040},
+			{".xdata", 0x488, 0xb000, 0x600, 0x7e00, 0x0, 0x0, 0x0, 0x0, 0x40300040},
+			{".bss", 0x1410, 0xc000, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0xc0600080},
+			{".idata", 0x990, 0xe000, 0xa00, 0x8400, 0x0, 0x0, 0x0, 0x0, 0xc0300040},
+			{".CRT", 0x68, 0xf000, 0x200, 0x8e00, 0x0, 0x0, 0x0, 0x0, 0xc0400040},
+			{".tls", 0x48, 0x10000, 0x200, 0x9000, 0x0, 0x0, 0x0, 0x0, 0xc0600040},
+		},
+		[]*Symbol{},
+	},
+}
+
+func isOptHdrEq(a, b interface{}) bool {
+	switch va := a.(type) {
+	case *OptionalHeader32:
+		vb, ok := b.(*OptionalHeader32)
+		if !ok {
+			return false
+		}
+		return *vb == *va
+	case *OptionalHeader64:
+		vb, ok := b.(*OptionalHeader64)
+		if !ok {
+			return false
+		}
+		return *vb == *va
+	case nil:
+		return b == nil
+	}
+	return false
 }
 
 func TestOpen(t *testing.T) {
@@ -90,6 +195,10 @@ func TestOpen(t *testing.T) {
 			t.Errorf("open %s:\n\thave %#v\n\twant %#v\n", tt.file, f.FileHeader, tt.hdr)
 			continue
 		}
+		if !isOptHdrEq(tt.opthdr, f.OptionalHeader) {
+			t.Errorf("open %s:\n\thave %#v\n\twant %#v\n", tt.file, f.OptionalHeader, tt.opthdr)
+			continue
+		}
 
 		for i, sh := range f.Sections {
 			if i >= len(tt.sections) {

src/pkg/debug/pe/pe.go

@@ -14,6 +14,78 @@ type FileHeader struct {
 	Characteristics      uint16
 }
 
+type DataDirectory struct {
+	VirtualAddress uint32
+	Size           uint32
+}
+
+type OptionalHeader32 struct {
+	Magic                       uint16
+	MajorLinkerVersion          uint8
+	MinorLinkerVersion          uint8
+	SizeOfCode                  uint32
+	SizeOfInitializedData       uint32
+	SizeOfUninitializedData     uint32
+	AddressOfEntryPoint         uint32
+	BaseOfCode                  uint32
+	BaseOfData                  uint32
+	ImageBase                   uint32
+	SectionAlignment            uint32
+	FileAlignment               uint32
+	MajorOperatingSystemVersion uint16
+	MinorOperatingSystemVersion uint16
+	MajorImageVersion           uint16
+	MinorImageVersion           uint16
+	MajorSubsystemVersion       uint16
+	MinorSubsystemVersion       uint16
+	Win32VersionValue           uint32
+	SizeOfImage                 uint32
+	SizeOfHeaders               uint32
+	CheckSum                    uint32
+	Subsystem                   uint16
+	DllCharacteristics          uint16
+	SizeOfStackReserve          uint32
+	SizeOfStackCommit           uint32
+	SizeOfHeapReserve           uint32
+	SizeOfHeapCommit            uint32
+	LoaderFlags                 uint32
+	NumberOfRvaAndSizes         uint32
+	DataDirectory               [16]DataDirectory
+}
+
+type OptionalHeader64 struct {
+	Magic                       uint16
+	MajorLinkerVersion          uint8
+	MinorLinkerVersion          uint8
+	SizeOfCode                  uint32
+	SizeOfInitializedData       uint32
+	SizeOfUninitializedData     uint32
+	AddressOfEntryPoint         uint32
+	BaseOfCode                  uint32
+	ImageBase                   uint64
+	SectionAlignment            uint32
+	FileAlignment               uint32
+	MajorOperatingSystemVersion uint16
+	MinorOperatingSystemVersion uint16
+	MajorImageVersion           uint16
+	MinorImageVersion           uint16
+	MajorSubsystemVersion       uint16
+	MinorSubsystemVersion       uint16
+	Win32VersionValue           uint32
+	SizeOfImage                 uint32
+	SizeOfHeaders               uint32
+	CheckSum                    uint32
+	Subsystem                   uint16
+	DllCharacteristics          uint16
+	SizeOfStackReserve          uint64
+	SizeOfStackCommit           uint64
+	SizeOfHeapReserve           uint64
+	SizeOfHeapCommit            uint64
+	LoaderFlags                 uint32
+	NumberOfRvaAndSizes         uint32
+	DataDirectory               [16]DataDirectory
+}
+
 type SectionHeader32 struct {
 	Name                 [8]uint8
 	VirtualSize          uint32