/
pe.go
1296 lines (1123 loc) · 31.2 KB
/
pe.go
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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package ld
import (
"cmd/internal/obj"
"cmd/internal/sys"
"encoding/binary"
"fmt"
"os"
"sort"
"strconv"
"strings"
)
type IMAGE_FILE_HEADER struct {
Machine uint16
NumberOfSections uint16
TimeDateStamp uint32
PointerToSymbolTable uint32
NumberOfSymbols uint32
SizeOfOptionalHeader uint16
Characteristics uint16
}
type IMAGE_DATA_DIRECTORY struct {
VirtualAddress uint32
Size uint32
}
type IMAGE_OPTIONAL_HEADER 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]IMAGE_DATA_DIRECTORY
}
type IMAGE_SECTION_HEADER struct {
Name [8]uint8
VirtualSize uint32
VirtualAddress uint32
SizeOfRawData uint32
PointerToRawData uint32
PointerToRelocations uint32
PointerToLineNumbers uint32
NumberOfRelocations uint16
NumberOfLineNumbers uint16
Characteristics uint32
}
type IMAGE_IMPORT_DESCRIPTOR struct {
OriginalFirstThunk uint32
TimeDateStamp uint32
ForwarderChain uint32
Name uint32
FirstThunk uint32
}
type IMAGE_EXPORT_DIRECTORY struct {
Characteristics uint32
TimeDateStamp uint32
MajorVersion uint16
MinorVersion uint16
Name uint32
Base uint32
NumberOfFunctions uint32
NumberOfNames uint32
AddressOfFunctions uint32
AddressOfNames uint32
AddressOfNameOrdinals uint32
}
const (
PEBASE = 0x00400000
// SectionAlignment must be greater than or equal to FileAlignment.
// The default is the page size for the architecture.
PESECTALIGN = 0x1000
// FileAlignment should be a power of 2 between 512 and 64 K, inclusive.
// The default is 512. If the SectionAlignment is less than
// the architecture's page size, then FileAlignment must match SectionAlignment.
PEFILEALIGN = 2 << 8
)
const (
IMAGE_FILE_MACHINE_I386 = 0x14c
IMAGE_FILE_MACHINE_AMD64 = 0x8664
IMAGE_FILE_RELOCS_STRIPPED = 0x0001
IMAGE_FILE_EXECUTABLE_IMAGE = 0x0002
IMAGE_FILE_LINE_NUMS_STRIPPED = 0x0004
IMAGE_FILE_LARGE_ADDRESS_AWARE = 0x0020
IMAGE_FILE_32BIT_MACHINE = 0x0100
IMAGE_FILE_DEBUG_STRIPPED = 0x0200
IMAGE_SCN_CNT_CODE = 0x00000020
IMAGE_SCN_CNT_INITIALIZED_DATA = 0x00000040
IMAGE_SCN_CNT_UNINITIALIZED_DATA = 0x00000080
IMAGE_SCN_MEM_EXECUTE = 0x20000000
IMAGE_SCN_MEM_READ = 0x40000000
IMAGE_SCN_MEM_WRITE = 0x80000000
IMAGE_SCN_MEM_DISCARDABLE = 0x2000000
IMAGE_SCN_LNK_NRELOC_OVFL = 0x1000000
IMAGE_SCN_ALIGN_32BYTES = 0x600000
IMAGE_DIRECTORY_ENTRY_EXPORT = 0
IMAGE_DIRECTORY_ENTRY_IMPORT = 1
IMAGE_DIRECTORY_ENTRY_RESOURCE = 2
IMAGE_DIRECTORY_ENTRY_EXCEPTION = 3
IMAGE_DIRECTORY_ENTRY_SECURITY = 4
IMAGE_DIRECTORY_ENTRY_BASERELOC = 5
IMAGE_DIRECTORY_ENTRY_DEBUG = 6
IMAGE_DIRECTORY_ENTRY_COPYRIGHT = 7
IMAGE_DIRECTORY_ENTRY_ARCHITECTURE = 7
IMAGE_DIRECTORY_ENTRY_GLOBALPTR = 8
IMAGE_DIRECTORY_ENTRY_TLS = 9
IMAGE_DIRECTORY_ENTRY_LOAD_CONFIG = 10
IMAGE_DIRECTORY_ENTRY_BOUND_IMPORT = 11
IMAGE_DIRECTORY_ENTRY_IAT = 12
IMAGE_DIRECTORY_ENTRY_DELAY_IMPORT = 13
IMAGE_DIRECTORY_ENTRY_COM_DESCRIPTOR = 14
IMAGE_SUBSYSTEM_WINDOWS_GUI = 2
IMAGE_SUBSYSTEM_WINDOWS_CUI = 3
)
// X64
type PE64_IMAGE_OPTIONAL_HEADER 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]IMAGE_DATA_DIRECTORY
}
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// PE (Portable Executable) file writing
// http://www.microsoft.com/whdc/system/platform/firmware/PECOFF.mspx
// DOS stub that prints out
// "This program cannot be run in DOS mode."
var dosstub = []uint8{
0x4d,
0x5a,
0x90,
0x00,
0x03,
0x00,
0x04,
0x00,
0x00,
0x00,
0x00,
0x00,
0xff,
0xff,
0x00,
0x00,
0x8b,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x40,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x80,
0x00,
0x00,
0x00,
0x0e,
0x1f,
0xba,
0x0e,
0x00,
0xb4,
0x09,
0xcd,
0x21,
0xb8,
0x01,
0x4c,
0xcd,
0x21,
0x54,
0x68,
0x69,
0x73,
0x20,
0x70,
0x72,
0x6f,
0x67,
0x72,
0x61,
0x6d,
0x20,
0x63,
0x61,
0x6e,
0x6e,
0x6f,
0x74,
0x20,
0x62,
0x65,
0x20,
0x72,
0x75,
0x6e,
0x20,
0x69,
0x6e,
0x20,
0x44,
0x4f,
0x53,
0x20,
0x6d,
0x6f,
0x64,
0x65,
0x2e,
0x0d,
0x0d,
0x0a,
0x24,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
0x00,
}
var rsrcsym *Symbol
var strtbl []byte
var PESECTHEADR int32
var PEFILEHEADR int32
var pe64 int
var pensect int
var nextsectoff int
var nextfileoff int
var textsect int
var datasect int
var bsssect int
var fh IMAGE_FILE_HEADER
var oh IMAGE_OPTIONAL_HEADER
var oh64 PE64_IMAGE_OPTIONAL_HEADER
var sh [16]IMAGE_SECTION_HEADER
var dd []IMAGE_DATA_DIRECTORY
type Imp struct {
s *Symbol
off uint64
next *Imp
argsize int
}
type Dll struct {
name string
nameoff uint64
thunkoff uint64
ms *Imp
next *Dll
}
var dr *Dll
var dexport [1024]*Symbol
var nexport int
func addpesection(ctxt *Link, name string, sectsize int, filesize int) *IMAGE_SECTION_HEADER {
if pensect == 16 {
Errorf(nil, "too many sections")
errorexit()
}
h := &sh[pensect]
pensect++
copy(h.Name[:], name)
h.VirtualSize = uint32(sectsize)
h.VirtualAddress = uint32(nextsectoff)
nextsectoff = int(Rnd(int64(nextsectoff)+int64(sectsize), PESECTALIGN))
h.PointerToRawData = uint32(nextfileoff)
if filesize > 0 {
h.SizeOfRawData = uint32(Rnd(int64(filesize), PEFILEALIGN))
nextfileoff += int(h.SizeOfRawData)
}
return h
}
func chksectoff(ctxt *Link, h *IMAGE_SECTION_HEADER, off int64) {
if off != int64(h.PointerToRawData) {
Errorf(nil, "%s.PointerToRawData = %#x, want %#x", cstring(h.Name[:]), uint64(int64(h.PointerToRawData)), uint64(off))
errorexit()
}
}
func chksectseg(ctxt *Link, h *IMAGE_SECTION_HEADER, s *Segment) {
if s.Vaddr-PEBASE != uint64(h.VirtualAddress) {
Errorf(nil, "%s.VirtualAddress = %#x, want %#x", cstring(h.Name[:]), uint64(int64(h.VirtualAddress)), uint64(int64(s.Vaddr-PEBASE)))
errorexit()
}
if s.Fileoff != uint64(h.PointerToRawData) {
Errorf(nil, "%s.PointerToRawData = %#x, want %#x", cstring(h.Name[:]), uint64(int64(h.PointerToRawData)), uint64(int64(s.Fileoff)))
errorexit()
}
}
func Peinit(ctxt *Link) {
var l int
switch SysArch.Family {
// 64-bit architectures
case sys.AMD64:
pe64 = 1
l = binary.Size(&oh64)
dd = oh64.DataDirectory[:]
// 32-bit architectures
default:
l = binary.Size(&oh)
dd = oh.DataDirectory[:]
}
PEFILEHEADR = int32(Rnd(int64(len(dosstub)+binary.Size(&fh)+l+binary.Size(&sh)), PEFILEALIGN))
PESECTHEADR = int32(Rnd(int64(PEFILEHEADR), PESECTALIGN))
nextsectoff = int(PESECTHEADR)
nextfileoff = int(PEFILEHEADR)
// some mingw libs depend on this symbol, for example, FindPESectionByName
ctxt.xdefine("__image_base__", obj.SDATA, PEBASE)
ctxt.xdefine("_image_base__", obj.SDATA, PEBASE)
}
func pewrite() {
Cseek(0)
if Linkmode != LinkExternal {
Cwrite(dosstub)
strnput("PE", 4)
}
binary.Write(&coutbuf, binary.LittleEndian, &fh)
if pe64 != 0 {
binary.Write(&coutbuf, binary.LittleEndian, &oh64)
} else {
binary.Write(&coutbuf, binary.LittleEndian, &oh)
}
binary.Write(&coutbuf, binary.LittleEndian, sh[:pensect])
}
func strput(s string) {
coutbuf.WriteString(s)
Cput(0)
// string must be padded to even size
if (len(s)+1)%2 != 0 {
Cput(0)
}
}
func initdynimport(ctxt *Link) *Dll {
var d *Dll
dr = nil
var m *Imp
for _, s := range ctxt.Syms.Allsym {
if !s.Attr.Reachable() || s.Type != obj.SDYNIMPORT {
continue
}
for d = dr; d != nil; d = d.next {
if d.name == s.Dynimplib {
m = new(Imp)
break
}
}
if d == nil {
d = new(Dll)
d.name = s.Dynimplib
d.next = dr
dr = d
m = new(Imp)
}
// Because external link requires properly stdcall decorated name,
// all external symbols in runtime use %n to denote that the number
// of uinptrs this function consumes. Store the argsize and discard
// the %n suffix if any.
m.argsize = -1
if i := strings.IndexByte(s.Extname, '%'); i >= 0 {
var err error
m.argsize, err = strconv.Atoi(s.Extname[i+1:])
if err != nil {
Errorf(s, "failed to parse stdcall decoration: %v", err)
}
m.argsize *= SysArch.PtrSize
s.Extname = s.Extname[:i]
}
m.s = s
m.next = d.ms
d.ms = m
}
if Linkmode == LinkExternal {
// Add real symbol name
for d := dr; d != nil; d = d.next {
for m = d.ms; m != nil; m = m.next {
m.s.Type = obj.SDATA
Symgrow(m.s, int64(SysArch.PtrSize))
dynName := m.s.Extname
// only windows/386 requires stdcall decoration
if SysArch.Family == sys.I386 && m.argsize >= 0 {
dynName += fmt.Sprintf("@%d", m.argsize)
}
dynSym := ctxt.Syms.Lookup(dynName, 0)
dynSym.Attr |= AttrReachable
dynSym.Type = obj.SHOSTOBJ
r := Addrel(m.s)
r.Sym = dynSym
r.Off = 0
r.Siz = uint8(SysArch.PtrSize)
r.Type = obj.R_ADDR
}
}
} else {
dynamic := ctxt.Syms.Lookup(".windynamic", 0)
dynamic.Attr |= AttrReachable
dynamic.Type = obj.SWINDOWS
for d := dr; d != nil; d = d.next {
for m = d.ms; m != nil; m = m.next {
m.s.Type = obj.SWINDOWS | obj.SSUB
m.s.Sub = dynamic.Sub
dynamic.Sub = m.s
m.s.Value = dynamic.Size
dynamic.Size += int64(SysArch.PtrSize)
}
dynamic.Size += int64(SysArch.PtrSize)
}
}
return dr
}
// peimporteddlls returns the gcc command line argument to link all imported
// DLLs.
func peimporteddlls() []string {
var dlls []string
for d := dr; d != nil; d = d.next {
dlls = append(dlls, "-l"+strings.TrimSuffix(d.name, ".dll"))
}
return dlls
}
func addimports(ctxt *Link, datsect *IMAGE_SECTION_HEADER) {
startoff := coutbuf.Offset()
dynamic := ctxt.Syms.Lookup(".windynamic", 0)
// skip import descriptor table (will write it later)
n := uint64(0)
for d := dr; d != nil; d = d.next {
n++
}
Cseek(startoff + int64(binary.Size(&IMAGE_IMPORT_DESCRIPTOR{}))*int64(n+1))
// write dll names
for d := dr; d != nil; d = d.next {
d.nameoff = uint64(coutbuf.Offset()) - uint64(startoff)
strput(d.name)
}
// write function names
var m *Imp
for d := dr; d != nil; d = d.next {
for m = d.ms; m != nil; m = m.next {
m.off = uint64(nextsectoff) + uint64(coutbuf.Offset()) - uint64(startoff)
Wputl(0) // hint
strput(m.s.Extname)
}
}
// write OriginalFirstThunks
oftbase := uint64(coutbuf.Offset()) - uint64(startoff)
n = uint64(coutbuf.Offset())
for d := dr; d != nil; d = d.next {
d.thunkoff = uint64(coutbuf.Offset()) - n
for m = d.ms; m != nil; m = m.next {
if pe64 != 0 {
Vputl(m.off)
} else {
Lputl(uint32(m.off))
}
}
if pe64 != 0 {
Vputl(0)
} else {
Lputl(0)
}
}
// add pe section and pad it at the end
n = uint64(coutbuf.Offset()) - uint64(startoff)
isect := addpesection(ctxt, ".idata", int(n), int(n))
isect.Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE
chksectoff(ctxt, isect, startoff)
strnput("", int(uint64(isect.SizeOfRawData)-n))
endoff := coutbuf.Offset()
// write FirstThunks (allocated in .data section)
ftbase := uint64(dynamic.Value) - uint64(datsect.VirtualAddress) - PEBASE
Cseek(int64(uint64(datsect.PointerToRawData) + ftbase))
for d := dr; d != nil; d = d.next {
for m = d.ms; m != nil; m = m.next {
if pe64 != 0 {
Vputl(m.off)
} else {
Lputl(uint32(m.off))
}
}
if pe64 != 0 {
Vputl(0)
} else {
Lputl(0)
}
}
// finally write import descriptor table
Cseek(startoff)
for d := dr; d != nil; d = d.next {
Lputl(uint32(uint64(isect.VirtualAddress) + oftbase + d.thunkoff))
Lputl(0)
Lputl(0)
Lputl(uint32(uint64(isect.VirtualAddress) + d.nameoff))
Lputl(uint32(uint64(datsect.VirtualAddress) + ftbase + d.thunkoff))
}
Lputl(0) //end
Lputl(0)
Lputl(0)
Lputl(0)
Lputl(0)
// update data directory
dd[IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress = isect.VirtualAddress
dd[IMAGE_DIRECTORY_ENTRY_IMPORT].Size = isect.VirtualSize
dd[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress = uint32(dynamic.Value - PEBASE)
dd[IMAGE_DIRECTORY_ENTRY_IAT].Size = uint32(dynamic.Size)
Cseek(endoff)
}
type byExtname []*Symbol
func (s byExtname) Len() int { return len(s) }
func (s byExtname) Swap(i, j int) { s[i], s[j] = s[j], s[i] }
func (s byExtname) Less(i, j int) bool { return s[i].Extname < s[j].Extname }
func initdynexport(ctxt *Link) {
nexport = 0
for _, s := range ctxt.Syms.Allsym {
if !s.Attr.Reachable() || !s.Attr.CgoExportDynamic() {
continue
}
if nexport+1 > len(dexport) {
Errorf(s, "pe dynexport table is full")
errorexit()
}
dexport[nexport] = s
nexport++
}
sort.Sort(byExtname(dexport[:nexport]))
}
func addexports(ctxt *Link) {
var e IMAGE_EXPORT_DIRECTORY
size := binary.Size(&e) + 10*nexport + len(*flagOutfile) + 1
for i := 0; i < nexport; i++ {
size += len(dexport[i].Extname) + 1
}
if nexport == 0 {
return
}
sect := addpesection(ctxt, ".edata", size, size)
sect.Characteristics = IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ
chksectoff(ctxt, sect, coutbuf.Offset())
va := int(sect.VirtualAddress)
dd[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress = uint32(va)
dd[IMAGE_DIRECTORY_ENTRY_EXPORT].Size = sect.VirtualSize
vaName := va + binary.Size(&e) + nexport*4
vaAddr := va + binary.Size(&e)
vaNa := va + binary.Size(&e) + nexport*8
e.Characteristics = 0
e.MajorVersion = 0
e.MinorVersion = 0
e.NumberOfFunctions = uint32(nexport)
e.NumberOfNames = uint32(nexport)
e.Name = uint32(va+binary.Size(&e)) + uint32(nexport)*10 // Program names.
e.Base = 1
e.AddressOfFunctions = uint32(vaAddr)
e.AddressOfNames = uint32(vaName)
e.AddressOfNameOrdinals = uint32(vaNa)
// put IMAGE_EXPORT_DIRECTORY
binary.Write(&coutbuf, binary.LittleEndian, &e)
// put EXPORT Address Table
for i := 0; i < nexport; i++ {
Lputl(uint32(dexport[i].Value - PEBASE))
}
// put EXPORT Name Pointer Table
v := int(e.Name + uint32(len(*flagOutfile)) + 1)
for i := 0; i < nexport; i++ {
Lputl(uint32(v))
v += len(dexport[i].Extname) + 1
}
// put EXPORT Ordinal Table
for i := 0; i < nexport; i++ {
Wputl(uint16(i))
}
// put Names
strnput(*flagOutfile, len(*flagOutfile)+1)
for i := 0; i < nexport; i++ {
strnput(dexport[i].Extname, len(dexport[i].Extname)+1)
}
strnput("", int(sect.SizeOfRawData-uint32(size)))
}
// perelocsect relocates symbols from first in section sect, and returns
// the total number of relocations emitted.
func perelocsect(ctxt *Link, sect *Section, syms []*Symbol) int {
// If main section has no bits, nothing to relocate.
if sect.Vaddr >= sect.Seg.Vaddr+sect.Seg.Filelen {
return 0
}
relocs := 0
sect.Reloff = uint64(coutbuf.Offset())
for i, s := range syms {
if !s.Attr.Reachable() {
continue
}
if uint64(s.Value) >= sect.Vaddr {
syms = syms[i:]
break
}
}
eaddr := int32(sect.Vaddr + sect.Length)
for _, sym := range syms {
if !sym.Attr.Reachable() {
continue
}
if sym.Value >= int64(eaddr) {
break
}
for ri := 0; ri < len(sym.R); ri++ {
r := &sym.R[ri]
if r.Done != 0 {
continue
}
if r.Xsym == nil {
Errorf(sym, "missing xsym in relocation")
continue
}
if r.Xsym.Dynid < 0 {
Errorf(sym, "reloc %d to non-coff symbol %s (outer=%s) %d", r.Type, r.Sym.Name, r.Xsym.Name, r.Sym.Type)
}
if !Thearch.PEreloc1(sym, r, int64(uint64(sym.Value+int64(r.Off))-PEBASE)) {
Errorf(sym, "unsupported obj reloc %d/%d to %s", r.Type, r.Siz, r.Sym.Name)
}
relocs++
}
}
sect.Rellen = uint64(coutbuf.Offset()) - sect.Reloff
return relocs
}
// peemitreloc emits relocation entries for go.o in external linking.
func peemitreloc(ctxt *Link, text, data, ctors *IMAGE_SECTION_HEADER) {
for coutbuf.Offset()&7 != 0 {
Cput(0)
}
text.PointerToRelocations = uint32(coutbuf.Offset())
// first entry: extended relocs
Lputl(0) // placeholder for number of relocation + 1
Lputl(0)
Wputl(0)
n := perelocsect(ctxt, Segtext.Sect, ctxt.Textp) + 1
for sect := Segtext.Sect.Next; sect != nil; sect = sect.Next {
n += perelocsect(ctxt, sect, datap)
}
cpos := coutbuf.Offset()
Cseek(int64(text.PointerToRelocations))
Lputl(uint32(n))
Cseek(cpos)
if n > 0x10000 {
n = 0x10000
text.Characteristics |= IMAGE_SCN_LNK_NRELOC_OVFL
} else {
text.PointerToRelocations += 10 // skip the extend reloc entry
}
text.NumberOfRelocations = uint16(n - 1)
data.PointerToRelocations = uint32(cpos)
// first entry: extended relocs
Lputl(0) // placeholder for number of relocation + 1
Lputl(0)
Wputl(0)
n = 1
for sect := Segdata.Sect; sect != nil; sect = sect.Next {
n += perelocsect(ctxt, sect, datap)
}
cpos = coutbuf.Offset()
Cseek(int64(data.PointerToRelocations))
Lputl(uint32(n))
Cseek(cpos)
if n > 0x10000 {
n = 0x10000
data.Characteristics |= IMAGE_SCN_LNK_NRELOC_OVFL
} else {
data.PointerToRelocations += 10 // skip the extend reloc entry
}
data.NumberOfRelocations = uint16(n - 1)
dottext := ctxt.Syms.Lookup(".text", 0)
ctors.NumberOfRelocations = 1
ctors.PointerToRelocations = uint32(coutbuf.Offset())
sectoff := ctors.VirtualAddress
Lputl(sectoff)
Lputl(uint32(dottext.Dynid))
switch obj.GOARCH {
default:
fmt.Fprintf(os.Stderr, "link: unknown architecture for PE: %q\n", obj.GOARCH)
os.Exit(2)
case "386":
Wputl(IMAGE_REL_I386_DIR32)
case "amd64":
Wputl(IMAGE_REL_AMD64_ADDR64)
}
}
func (ctxt *Link) dope() {
/* relocation table */
rel := ctxt.Syms.Lookup(".rel", 0)
rel.Attr |= AttrReachable
rel.Type = obj.SELFROSECT
initdynimport(ctxt)
initdynexport(ctxt)
}
func strtbladd(name string) int {
off := len(strtbl) + 4 // offset includes 4-byte length at beginning of table
strtbl = append(strtbl, name...)
strtbl = append(strtbl, 0)
return off
}
/*
* For more than 8 characters section names, name contains a slash (/) that is
* followed by an ASCII representation of a decimal number that is an offset into
* the string table.
* reference: pecoff_v8.docx Page 24.
* <http://www.microsoft.com/whdc/system/platform/firmware/PECOFFdwn.mspx>
*/
func newPEDWARFSection(ctxt *Link, name string, size int64) *IMAGE_SECTION_HEADER {
if size == 0 {
return nil
}
off := strtbladd(name)
s := fmt.Sprintf("/%d", off)
h := addpesection(ctxt, s, int(size), int(size))
h.Characteristics = IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_DISCARDABLE
return h
}
// writePESymTableRecords writes all COFF symbol table records.
// It returns number of records written.
func writePESymTableRecords(ctxt *Link) int {
var symcnt int
put := func(ctxt *Link, s *Symbol, name string, type_ SymbolType, addr int64, gotype *Symbol) {
if s == nil {
return
}
if s.Sect == nil && type_ != UndefinedSym {
return
}
switch type_ {
default:
return
case DataSym, BSSSym, TextSym, UndefinedSym:
}
// only windows/386 requires underscore prefix on external symbols
if SysArch.Family == sys.I386 &&
Linkmode == LinkExternal &&
(s.Type != obj.SDYNIMPORT || s.Attr.CgoExport()) &&
s.Name == s.Extname &&
s.Name != "_main" {
s.Name = "_" + s.Name
}
var typ uint16
var sect int
var value int64
// Note: although address of runtime.edata (type SDATA) is at the start of .bss section
// it still belongs to the .data section, not the .bss section.
if uint64(s.Value) >= Segdata.Vaddr+Segdata.Filelen && s.Type != obj.SDATA && Linkmode == LinkExternal {
value = int64(uint64(s.Value) - Segdata.Vaddr - Segdata.Filelen)
sect = bsssect
} else if uint64(s.Value) >= Segdata.Vaddr {
value = int64(uint64(s.Value) - Segdata.Vaddr)
sect = datasect
} else if uint64(s.Value) >= Segtext.Vaddr {
value = int64(uint64(s.Value) - Segtext.Vaddr)
sect = textsect
} else if type_ == UndefinedSym {
typ = IMAGE_SYM_DTYPE_FUNCTION
} else {
Errorf(s, "addpesym %#x", addr)
}
// write COFF symbol table record
if len(s.Name) > 8 {
Lputl(0)
Lputl(uint32(strtbladd(s.Name)))
} else {
strnput(s.Name, 8)
}
Lputl(uint32(value))
Wputl(uint16(sect))
if typ != 0 {
Wputl(typ)
} else if Linkmode == LinkExternal {
Wputl(0)
} else {
Wputl(0x0308) // "array of structs"
}
Cput(2) // storage class: external
Cput(0) // no aux entries
s.Dynid = int32(symcnt)
symcnt++
}
if Linkmode == LinkExternal {
for d := dr; d != nil; d = d.next {
for m := d.ms; m != nil; m = m.next {
s := m.s.R[0].Xsym