1 // Copyright 2010 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
5 // Package loadpe implements a PE/COFF file reader.
12 "cmd/link/internal/sym"
23 // TODO: the Microsoft doco says IMAGE_SYM_DTYPE_ARRAY is 3 (same with IMAGE_SYM_DTYPE_POINTER and IMAGE_SYM_DTYPE_FUNCTION)
24 IMAGE_SYM_UNDEFINED = 0
25 IMAGE_SYM_ABSOLUTE = -1
27 IMAGE_SYM_TYPE_NULL = 0
28 IMAGE_SYM_TYPE_VOID = 1
29 IMAGE_SYM_TYPE_CHAR = 2
30 IMAGE_SYM_TYPE_SHORT = 3
31 IMAGE_SYM_TYPE_INT = 4
32 IMAGE_SYM_TYPE_LONG = 5
33 IMAGE_SYM_TYPE_FLOAT = 6
34 IMAGE_SYM_TYPE_DOUBLE = 7
35 IMAGE_SYM_TYPE_STRUCT = 8
36 IMAGE_SYM_TYPE_UNION = 9
37 IMAGE_SYM_TYPE_ENUM = 10
38 IMAGE_SYM_TYPE_MOE = 11
39 IMAGE_SYM_TYPE_BYTE = 12
40 IMAGE_SYM_TYPE_WORD = 13
41 IMAGE_SYM_TYPE_UINT = 14
42 IMAGE_SYM_TYPE_DWORD = 15
43 IMAGE_SYM_TYPE_PCODE = 32768
44 IMAGE_SYM_DTYPE_NULL = 0
45 IMAGE_SYM_DTYPE_POINTER = 0x10
46 IMAGE_SYM_DTYPE_FUNCTION = 0x20
47 IMAGE_SYM_DTYPE_ARRAY = 0x30
48 IMAGE_SYM_CLASS_END_OF_FUNCTION = -1
49 IMAGE_SYM_CLASS_NULL = 0
50 IMAGE_SYM_CLASS_AUTOMATIC = 1
51 IMAGE_SYM_CLASS_EXTERNAL = 2
52 IMAGE_SYM_CLASS_STATIC = 3
53 IMAGE_SYM_CLASS_REGISTER = 4
54 IMAGE_SYM_CLASS_EXTERNAL_DEF = 5
55 IMAGE_SYM_CLASS_LABEL = 6
56 IMAGE_SYM_CLASS_UNDEFINED_LABEL = 7
57 IMAGE_SYM_CLASS_MEMBER_OF_STRUCT = 8
58 IMAGE_SYM_CLASS_ARGUMENT = 9
59 IMAGE_SYM_CLASS_STRUCT_TAG = 10
60 IMAGE_SYM_CLASS_MEMBER_OF_UNION = 11
61 IMAGE_SYM_CLASS_UNION_TAG = 12
62 IMAGE_SYM_CLASS_TYPE_DEFINITION = 13
63 IMAGE_SYM_CLASS_UNDEFINED_STATIC = 14
64 IMAGE_SYM_CLASS_ENUM_TAG = 15
65 IMAGE_SYM_CLASS_MEMBER_OF_ENUM = 16
66 IMAGE_SYM_CLASS_REGISTER_PARAM = 17
67 IMAGE_SYM_CLASS_BIT_FIELD = 18
68 IMAGE_SYM_CLASS_FAR_EXTERNAL = 68 /* Not in PECOFF v8 spec */
69 IMAGE_SYM_CLASS_BLOCK = 100
70 IMAGE_SYM_CLASS_FUNCTION = 101
71 IMAGE_SYM_CLASS_END_OF_STRUCT = 102
72 IMAGE_SYM_CLASS_FILE = 103
73 IMAGE_SYM_CLASS_SECTION = 104
74 IMAGE_SYM_CLASS_WEAK_EXTERNAL = 105
75 IMAGE_SYM_CLASS_CLR_TOKEN = 107
76 IMAGE_REL_I386_ABSOLUTE = 0x0000
77 IMAGE_REL_I386_DIR16 = 0x0001
78 IMAGE_REL_I386_REL16 = 0x0002
79 IMAGE_REL_I386_DIR32 = 0x0006
80 IMAGE_REL_I386_DIR32NB = 0x0007
81 IMAGE_REL_I386_SEG12 = 0x0009
82 IMAGE_REL_I386_SECTION = 0x000A
83 IMAGE_REL_I386_SECREL = 0x000B
84 IMAGE_REL_I386_TOKEN = 0x000C
85 IMAGE_REL_I386_SECREL7 = 0x000D
86 IMAGE_REL_I386_REL32 = 0x0014
87 IMAGE_REL_AMD64_ABSOLUTE = 0x0000
88 IMAGE_REL_AMD64_ADDR64 = 0x0001
89 IMAGE_REL_AMD64_ADDR32 = 0x0002
90 IMAGE_REL_AMD64_ADDR32NB = 0x0003
91 IMAGE_REL_AMD64_REL32 = 0x0004
92 IMAGE_REL_AMD64_REL32_1 = 0x0005
93 IMAGE_REL_AMD64_REL32_2 = 0x0006
94 IMAGE_REL_AMD64_REL32_3 = 0x0007
95 IMAGE_REL_AMD64_REL32_4 = 0x0008
96 IMAGE_REL_AMD64_REL32_5 = 0x0009
97 IMAGE_REL_AMD64_SECTION = 0x000A
98 IMAGE_REL_AMD64_SECREL = 0x000B
99 IMAGE_REL_AMD64_SECREL7 = 0x000C
100 IMAGE_REL_AMD64_TOKEN = 0x000D
101 IMAGE_REL_AMD64_SREL32 = 0x000E
102 IMAGE_REL_AMD64_PAIR = 0x000F
103 IMAGE_REL_AMD64_SSPAN32 = 0x0010
104 IMAGE_REL_ARM_ABSOLUTE = 0x0000
105 IMAGE_REL_ARM_ADDR32 = 0x0001
106 IMAGE_REL_ARM_ADDR32NB = 0x0002
107 IMAGE_REL_ARM_BRANCH24 = 0x0003
108 IMAGE_REL_ARM_BRANCH11 = 0x0004
109 IMAGE_REL_ARM_SECTION = 0x000E
110 IMAGE_REL_ARM_SECREL = 0x000F
111 IMAGE_REL_ARM_MOV32 = 0x0010
112 IMAGE_REL_THUMB_MOV32 = 0x0011
113 IMAGE_REL_THUMB_BRANCH20 = 0x0012
114 IMAGE_REL_THUMB_BRANCH24 = 0x0014
115 IMAGE_REL_THUMB_BLX23 = 0x0015
116 IMAGE_REL_ARM_PAIR = 0x0016
119 // TODO(crawshaw): de-duplicate these symbols with cmd/internal/ld, ideally in debug/pe.
121 IMAGE_SCN_CNT_CODE = 0x00000020
122 IMAGE_SCN_CNT_INITIALIZED_DATA = 0x00000040
123 IMAGE_SCN_CNT_UNINITIALIZED_DATA = 0x00000080
124 IMAGE_SCN_MEM_DISCARDABLE = 0x02000000
125 IMAGE_SCN_MEM_EXECUTE = 0x20000000
126 IMAGE_SCN_MEM_READ = 0x40000000
127 IMAGE_SCN_MEM_WRITE = 0x80000000
130 // TODO(brainman): maybe just add ReadAt method to bio.Reader instead of creating peBiobuf
132 // peBiobuf makes bio.Reader look like io.ReaderAt.
133 type peBiobuf bio.Reader
135 func (f *peBiobuf) ReadAt(p []byte, off int64) (int, error) {
136 ret := ((*bio.Reader)(f)).MustSeek(off, 0)
138 return 0, errors.New("fail to seek")
147 // Load loads the PE file pn from input.
148 // Symbols are written into syms, and a slice of the text symbols is returned.
149 // If an .rsrc section is found, its symbol is returned as rsrc.
150 func Load(arch *sys.Arch, syms *sym.Symbols, input *bio.Reader, pkg string, length int64, pn string) (textp []*sym.Symbol, rsrc *sym.Symbol, err error) {
151 localSymVersion := syms.IncVersion()
153 sectsyms := make(map[*pe.Section]*sym.Symbol)
154 sectdata := make(map[*pe.Section][]byte)
156 // Some input files are archives containing multiple of
157 // object files, and pe.NewFile seeks to the start of
158 // input file and get confused. Create section reader
159 // to stop pe.NewFile looking before current position.
160 sr := io.NewSectionReader((*peBiobuf)(input), input.Offset(), 1<<63-1)
162 // TODO: replace pe.NewFile with pe.Load (grep for "add Load function" in debug/pe for details)
163 f, err := pe.NewFile(sr)
169 // TODO return error if found .cormeta
171 // create symbols for mapped sections
172 for _, sect := range f.Sections {
173 if sect.Characteristics&IMAGE_SCN_MEM_DISCARDABLE != 0 {
177 if sect.Characteristics&(IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_CNT_UNINITIALIZED_DATA) == 0 {
178 // This has been seen for .idata sections, which we
179 // want to ignore. See issues 5106 and 5273.
183 name := fmt.Sprintf("%s(%s)", pkg, sect.Name)
184 s := syms.Lookup(name, localSymVersion)
186 switch sect.Characteristics & (IMAGE_SCN_CNT_UNINITIALIZED_DATA | IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE | IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE) {
187 case IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ: //.rdata
190 case IMAGE_SCN_CNT_UNINITIALIZED_DATA | IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE: //.bss
191 s.Type = sym.SNOPTRBSS
193 case IMAGE_SCN_CNT_INITIALIZED_DATA | IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE: //.data
194 s.Type = sym.SNOPTRDATA
196 case IMAGE_SCN_CNT_CODE | IMAGE_SCN_MEM_EXECUTE | IMAGE_SCN_MEM_READ: //.text
200 return nil, nil, fmt.Errorf("unexpected flags %#06x for PE section %s", sect.Characteristics, sect.Name)
203 if s.Type != sym.SNOPTRBSS {
204 data, err := sect.Data()
208 sectdata[sect] = data
211 s.Size = int64(sect.Size)
213 if sect.Name == ".rsrc" {
219 for _, rsect := range f.Sections {
220 if _, found := sectsyms[rsect]; !found {
223 if rsect.NumberOfRelocations == 0 {
226 if rsect.Characteristics&IMAGE_SCN_MEM_DISCARDABLE != 0 {
229 if rsect.Characteristics&(IMAGE_SCN_CNT_CODE|IMAGE_SCN_CNT_INITIALIZED_DATA|IMAGE_SCN_CNT_UNINITIALIZED_DATA) == 0 {
230 // This has been seen for .idata sections, which we
231 // want to ignore. See issues 5106 and 5273.
235 rs := make([]sym.Reloc, rsect.NumberOfRelocations)
236 for j, r := range rsect.Relocs {
238 if int(r.SymbolTableIndex) >= len(f.COFFSymbols) {
239 return nil, nil, fmt.Errorf("relocation number %d symbol index idx=%d cannot be large then number of symbols %d", j, r.SymbolTableIndex, len(f.COFFSymbols))
241 pesym := &f.COFFSymbols[r.SymbolTableIndex]
242 gosym, err := readpesym(arch, syms, f, pesym, sectsyms, localSymVersion)
247 name, err := pesym.FullName(f.StringTable)
249 name = string(pesym.Name[:])
251 return nil, nil, fmt.Errorf("reloc of invalid sym %s idx=%d type=%d", name, r.SymbolTableIndex, pesym.Type)
256 rp.Off = int32(r.VirtualAddress)
259 return nil, nil, fmt.Errorf("%s: unsupported arch %v", pn, arch.Family)
260 case sys.I386, sys.AMD64:
263 return nil, nil, fmt.Errorf("%s: %v: unknown relocation type %v", pn, sectsyms[rsect], r.Type)
265 case IMAGE_REL_I386_REL32, IMAGE_REL_AMD64_REL32,
266 IMAGE_REL_AMD64_ADDR32, // R_X86_64_PC32
267 IMAGE_REL_AMD64_ADDR32NB:
268 rp.Type = objabi.R_PCREL
270 rp.Add = int64(int32(binary.LittleEndian.Uint32(sectdata[rsect][rp.Off:])))
272 case IMAGE_REL_I386_DIR32NB, IMAGE_REL_I386_DIR32:
273 rp.Type = objabi.R_ADDR
275 // load addend from image
276 rp.Add = int64(int32(binary.LittleEndian.Uint32(sectdata[rsect][rp.Off:])))
278 case IMAGE_REL_AMD64_ADDR64: // R_X86_64_64
281 rp.Type = objabi.R_ADDR
283 // load addend from image
284 rp.Add = int64(binary.LittleEndian.Uint64(sectdata[rsect][rp.Off:]))
290 return nil, nil, fmt.Errorf("%s: %v: unknown ARM relocation type %v", pn, sectsyms[rsect], r.Type)
292 case IMAGE_REL_ARM_SECREL:
293 rp.Type = objabi.R_PCREL
295 rp.Add = int64(int32(binary.LittleEndian.Uint32(sectdata[rsect][rp.Off:])))
297 case IMAGE_REL_ARM_ADDR32:
298 rp.Type = objabi.R_ADDR
300 rp.Add = int64(int32(binary.LittleEndian.Uint32(sectdata[rsect][rp.Off:])))
302 case IMAGE_REL_ARM_BRANCH24:
303 rp.Type = objabi.R_CALLARM
305 rp.Add = int64(int32(binary.LittleEndian.Uint32(sectdata[rsect][rp.Off:])))
309 // ld -r could generate multiple section symbols for the
310 // same section but with different values, we have to take
313 rp.Add += int64(pesym.Value)
317 sort.Sort(sym.RelocByOff(rs[:rsect.NumberOfRelocations]))
321 s.R = s.R[:rsect.NumberOfRelocations]
324 // enter sub-symbols into symbol table.
325 for i, numaux := 0, 0; i < len(f.COFFSymbols); i += numaux + 1 {
326 pesym := &f.COFFSymbols[i]
328 numaux = int(pesym.NumberOfAuxSymbols)
330 name, err := pesym.FullName(f.StringTable)
340 if int(pesym.SectionNumber) > len(f.Sections) {
343 if pesym.SectionNumber == IMAGE_SYM_DEBUG {
347 if pesym.SectionNumber > 0 {
348 sect = f.Sections[pesym.SectionNumber-1]
349 if _, found := sectsyms[sect]; !found {
354 s, err := readpesym(arch, syms, f, pesym, sectsyms, localSymVersion)
359 if pesym.SectionNumber == 0 { // extern
360 if s.Type == sym.SDYNIMPORT {
361 s.SetPlt(-2) // flag for dynimport in PE object files.
363 if s.Type == sym.SXREF && pesym.Value > 0 { // global data
364 s.Type = sym.SNOPTRDATA
365 s.Size = int64(pesym.Value)
369 } else if pesym.SectionNumber > 0 && int(pesym.SectionNumber) <= len(f.Sections) {
370 sect = f.Sections[pesym.SectionNumber-1]
371 if _, found := sectsyms[sect]; !found {
372 return nil, nil, fmt.Errorf("%s: %v: missing sect.sym", pn, s)
375 return nil, nil, fmt.Errorf("%s: %v: sectnum < 0!", pn, s)
379 return nil, rsrc, nil
383 if s.Attr.DuplicateOK() {
386 return nil, nil, fmt.Errorf("%s: duplicate symbol reference: %s in both %s and %s", pn, s.Name, s.Outer.Name, sectsyms[sect].Name)
389 sectsym := sectsyms[sect]
392 s.Type = sectsym.Type
393 s.Attr |= sym.AttrSubSymbol
394 s.Value = int64(pesym.Value)
397 if sectsym.Type == sym.STEXT {
398 if s.Attr.External() && !s.Attr.DuplicateOK() {
399 return nil, nil, fmt.Errorf("%s: duplicate symbol definition", s.Name)
401 s.Attr |= sym.AttrExternal
405 // Sort outer lists by address, adding to textp.
406 // This keeps textp in increasing address order.
407 for _, sect := range f.Sections {
413 s.Sub = sym.SortSub(s.Sub)
415 if s.Type == sym.STEXT {
417 return nil, nil, fmt.Errorf("symbol %s listed multiple times", s.Name)
419 s.Attr |= sym.AttrOnList
420 textp = append(textp, s)
421 for s = s.Sub; s != nil; s = s.Sub {
423 return nil, nil, fmt.Errorf("symbol %s listed multiple times", s.Name)
425 s.Attr |= sym.AttrOnList
426 textp = append(textp, s)
431 return textp, rsrc, nil
434 func issect(s *pe.COFFSymbol) bool {
435 return s.StorageClass == IMAGE_SYM_CLASS_STATIC && s.Type == 0 && s.Name[0] == '.'
438 func readpesym(arch *sys.Arch, syms *sym.Symbols, f *pe.File, pesym *pe.COFFSymbol, sectsyms map[*pe.Section]*sym.Symbol, localSymVersion int) (*sym.Symbol, error) {
439 symname, err := pesym.FullName(f.StringTable)
445 name = sectsyms[f.Sections[pesym.SectionNumber-1]].Name
450 if name == "__imp___acrt_iob_func" {
451 // Do not rename __imp___acrt_iob_func into __acrt_iob_func,
452 // becasue __imp___acrt_iob_func symbol is real
453 // (see commit b295099 from git://git.code.sf.net/p/mingw-w64/mingw-w64 for detials).
455 name = strings.TrimPrefix(name, "__imp_") // __imp_Name => Name
458 if name == "__imp____acrt_iob_func" {
459 // Do not rename __imp____acrt_iob_func into ___acrt_iob_func,
460 // becasue __imp____acrt_iob_func symbol is real
461 // (see commit b295099 from git://git.code.sf.net/p/mingw-w64/mingw-w64 for detials).
463 name = strings.TrimPrefix(name, "__imp_") // __imp_Name => Name
466 name = name[1:] // _Name => Name
472 if i := strings.LastIndex(name, "@"); i >= 0 {
479 return nil, fmt.Errorf("%s: invalid symbol type %d", symname, pesym.Type)
481 case IMAGE_SYM_DTYPE_FUNCTION, IMAGE_SYM_DTYPE_NULL:
482 switch pesym.StorageClass {
483 case IMAGE_SYM_CLASS_EXTERNAL: //global
484 s = syms.Lookup(name, 0)
486 case IMAGE_SYM_CLASS_NULL, IMAGE_SYM_CLASS_STATIC, IMAGE_SYM_CLASS_LABEL:
487 s = syms.Lookup(name, localSymVersion)
488 s.Attr |= sym.AttrDuplicateOK
491 return nil, fmt.Errorf("%s: invalid symbol binding %d", symname, pesym.StorageClass)
495 if s != nil && s.Type == 0 && (pesym.StorageClass != IMAGE_SYM_CLASS_STATIC || pesym.Value != 0) {
498 if strings.HasPrefix(symname, "__imp_") {
499 s.SetGot(-2) // flag for __imp_