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Diffstat (limited to 'src/debug/pe/file.go')
-rw-r--r--src/debug/pe/file.go199
1 files changed, 65 insertions, 134 deletions
diff --git a/src/debug/pe/file.go b/src/debug/pe/file.go
index 1acc368e1b..1cd84d5727 100644
--- a/src/debug/pe/file.go
+++ b/src/debug/pe/file.go
@@ -8,11 +8,9 @@ package pe
import (
"debug/dwarf"
"encoding/binary"
- "errors"
"fmt"
"io"
"os"
- "strconv"
)
// A File represents an open PE file.
@@ -20,83 +18,13 @@ type File struct {
FileHeader
OptionalHeader interface{} // of type *OptionalHeader32 or *OptionalHeader64
Sections []*Section
- Symbols []*Symbol
+ Symbols []*Symbol // COFF symbols with auxiliary symbol records removed
+ COFFSymbols []COFFSymbol // all COFF symbols (including auxiliary symbol records)
+ StringTable StringTable
closer io.Closer
}
-type SectionHeader struct {
- Name string
- VirtualSize uint32
- VirtualAddress uint32
- Size uint32
- Offset uint32
- PointerToRelocations uint32
- PointerToLineNumbers uint32
- NumberOfRelocations uint16
- NumberOfLineNumbers uint16
- Characteristics uint32
-}
-
-type Section struct {
- SectionHeader
-
- // Embed ReaderAt for ReadAt method.
- // Do not embed SectionReader directly
- // to avoid having Read and Seek.
- // If a client wants Read and Seek it must use
- // Open() to avoid fighting over the seek offset
- // with other clients.
- io.ReaderAt
- sr *io.SectionReader
-}
-
-type Symbol struct {
- Name string
- Value uint32
- SectionNumber int16
- Type uint16
- StorageClass uint8
-}
-
-type ImportDirectory struct {
- OriginalFirstThunk uint32
- TimeDateStamp uint32
- ForwarderChain uint32
- Name uint32
- FirstThunk uint32
-
- dll string
-}
-
-// Data reads and returns the contents of the PE section.
-func (s *Section) Data() ([]byte, error) {
- dat := make([]byte, s.sr.Size())
- n, err := s.sr.ReadAt(dat, 0)
- if n == len(dat) {
- err = nil
- }
- return dat[0:n], err
-}
-
-// Open returns a new ReadSeeker reading the PE section.
-func (s *Section) Open() io.ReadSeeker { return io.NewSectionReader(s.sr, 0, 1<<63-1) }
-
-type FormatError struct {
- off int64
- msg string
- val interface{}
-}
-
-func (e *FormatError) Error() string {
- msg := e.msg
- if e.val != nil {
- msg += fmt.Sprintf(" '%v'", e.val)
- }
- msg += fmt.Sprintf(" in record at byte %#x", e.off)
- return msg
-}
-
// Open opens the named file using os.Open and prepares it for use as a PE binary.
func Open(name string) (*File, error) {
f, err := os.Open(name)
@@ -129,6 +57,8 @@ var (
sizeofOptionalHeader64 = uint16(binary.Size(OptionalHeader64{}))
)
+// TODO(brainman): add Load function, as a replacement for NewFile, that does not call removeAuxSymbols (for performance)
+
// NewFile creates a new File for accessing a PE binary in an underlying reader.
func NewFile(r io.ReaderAt) (*File, error) {
f := new(File)
@@ -144,66 +74,42 @@ func NewFile(r io.ReaderAt) (*File, error) {
var sign [4]byte
r.ReadAt(sign[:], signoff)
if !(sign[0] == 'P' && sign[1] == 'E' && sign[2] == 0 && sign[3] == 0) {
- return nil, errors.New("Invalid PE File Format.")
+ return nil, fmt.Errorf("Invalid PE COFF file signature of %v.", sign)
}
base = signoff + 4
} else {
base = int64(0)
}
- sr.Seek(base, os.SEEK_SET)
+ sr.Seek(base, io.SeekStart)
if err := binary.Read(sr, binary.LittleEndian, &f.FileHeader); err != nil {
return nil, err
}
- if f.FileHeader.Machine != IMAGE_FILE_MACHINE_UNKNOWN && f.FileHeader.Machine != IMAGE_FILE_MACHINE_AMD64 && f.FileHeader.Machine != IMAGE_FILE_MACHINE_I386 {
- return nil, errors.New("Invalid PE File Format.")
+ switch f.FileHeader.Machine {
+ case IMAGE_FILE_MACHINE_UNKNOWN, IMAGE_FILE_MACHINE_AMD64, IMAGE_FILE_MACHINE_I386:
+ default:
+ return nil, fmt.Errorf("Unrecognised COFF file header machine value of 0x%x.", f.FileHeader.Machine)
}
- var ss []byte
- if f.FileHeader.NumberOfSymbols > 0 {
- // Get COFF string table, which is located at the end of the COFF symbol table.
- sr.Seek(int64(f.FileHeader.PointerToSymbolTable+COFFSymbolSize*f.FileHeader.NumberOfSymbols), os.SEEK_SET)
- var l uint32
- if err := binary.Read(sr, binary.LittleEndian, &l); err != nil {
- return nil, err
- }
- ss = make([]byte, l)
- if _, err := r.ReadAt(ss, int64(f.FileHeader.PointerToSymbolTable+COFFSymbolSize*f.FileHeader.NumberOfSymbols)); err != nil {
- return nil, err
- }
+ var err error
- // Process COFF symbol table.
- sr.Seek(int64(f.FileHeader.PointerToSymbolTable), os.SEEK_SET)
- aux := uint8(0)
- for i := 0; i < int(f.FileHeader.NumberOfSymbols); i++ {
- cs := new(COFFSymbol)
- if err := binary.Read(sr, binary.LittleEndian, cs); err != nil {
- return nil, err
- }
- if aux > 0 {
- aux--
- continue
- }
- var name string
- if cs.Name[0] == 0 && cs.Name[1] == 0 && cs.Name[2] == 0 && cs.Name[3] == 0 {
- si := int(binary.LittleEndian.Uint32(cs.Name[4:]))
- name, _ = getString(ss, si)
- } else {
- name = cstring(cs.Name[:])
- }
- aux = cs.NumberOfAuxSymbols
- s := &Symbol{
- Name: name,
- Value: cs.Value,
- SectionNumber: cs.SectionNumber,
- Type: cs.Type,
- StorageClass: cs.StorageClass,
- }
- f.Symbols = append(f.Symbols, s)
- }
+ // Read string table.
+ f.StringTable, err = readStringTable(&f.FileHeader, sr)
+ if err != nil {
+ return nil, err
+ }
+
+ // Read symbol table.
+ f.COFFSymbols, err = readCOFFSymbols(&f.FileHeader, sr)
+ if err != nil {
+ return nil, err
+ }
+ f.Symbols, err = removeAuxSymbols(f.COFFSymbols, f.StringTable)
+ if err != nil {
+ return nil, err
}
// Read optional header.
- sr.Seek(base, os.SEEK_SET)
+ sr.Seek(base, io.SeekStart)
if err := binary.Read(sr, binary.LittleEndian, &f.FileHeader); err != nil {
return nil, err
}
@@ -235,12 +141,9 @@ func NewFile(r io.ReaderAt) (*File, error) {
if err := binary.Read(sr, binary.LittleEndian, sh); err != nil {
return nil, err
}
- var name string
- if sh.Name[0] == '\x2F' {
- si, _ := strconv.Atoi(cstring(sh.Name[1:]))
- name, _ = getString(ss, si)
- } else {
- name = cstring(sh.Name[0:])
+ name, err := sh.fullName(f.StringTable)
+ if err != nil {
+ return nil, err
}
s := new(Section)
s.SectionHeader = SectionHeader{
@@ -259,14 +162,15 @@ func NewFile(r io.ReaderAt) (*File, error) {
s.ReaderAt = s.sr
f.Sections[i] = s
}
- return f, nil
-}
-
-func cstring(b []byte) string {
- var i int
- for i = 0; i < len(b) && b[i] != 0; i++ {
+ for i := range f.Sections {
+ var err error
+ f.Sections[i].Relocs, err = readRelocs(&f.Sections[i].SectionHeader, sr)
+ if err != nil {
+ return nil, err
+ }
}
- return string(b[0:i])
+
+ return f, nil
}
// getString extracts a string from symbol string table.
@@ -320,6 +224,18 @@ func (f *File) DWARF() (*dwarf.Data, error) {
return dwarf.New(abbrev, nil, nil, info, line, nil, ranges, str)
}
+// TODO(brainman): document ImportDirectory once we decide what to do with it.
+
+type ImportDirectory struct {
+ OriginalFirstThunk uint32
+ TimeDateStamp uint32
+ ForwarderChain uint32
+ Name uint32
+ FirstThunk uint32
+
+ dll string
+}
+
// ImportedSymbols returns the names of all symbols
// referred to by the binary f that are expected to be
// satisfied by other libraries at dynamic load time.
@@ -347,6 +263,12 @@ func (f *File) ImportedSymbols() ([]string, error) {
}
ida = append(ida, dt)
}
+ // TODO(brainman): this needs to be rewritten
+ // ds.Data() return contets of .idata section. Why store in variable called "names"?
+ // Why we are retrieving it second time? We already have it in "d", and it is not modified anywhere.
+ // getString does not extracts a string from symbol string table (as getString doco says).
+ // Why ds.Data() called again and again in the loop?
+ // Needs test before rewrite.
names, _ := ds.Data()
var all []string
for _, dt := range ida {
@@ -395,3 +317,12 @@ func (f *File) ImportedLibraries() ([]string, error) {
// cgo -dynimport don't use this for windows PE, so just return.
return nil, nil
}
+
+// FormatError is unused.
+// The type is retained for compatibility.
+type FormatError struct {
+}
+
+func (e *FormatError) Error() string {
+ return "unknown error"
+}
generated by cgit v1.3-6-g1900 (git 2.53.0) at 2026-04-17 21:44:52 +0000