func hasDynTag(f *elf.File, tag elf.DynTag) bool {
ds := f.SectionByType(elf.SHT_DYNAMIC)
if ds == nil {
return false
}
d, err := ds.Data()
if err != nil {
return false
}
for len(d) > 0 {
var t elf.DynTag
switch f.Class {
case elf.ELFCLASS32:
t = elf.DynTag(f.ByteOrder.Uint32(d[0:4]))
d = d[8:]
case elf.ELFCLASS64:
t = elf.DynTag(f.ByteOrder.Uint64(d[0:8]))
d = d[16:]
}
if t == tag {
return true
}
}
return false
}
func hasDynTag(t *testing.T, f *elf.File, tag elf.DynTag) bool {
ds := f.SectionByType(elf.SHT_DYNAMIC)
if ds == nil {
t.Error("no SHT_DYNAMIC section")
return false
}
d, err := ds.Data()
if err != nil {
t.Errorf("can't read SHT_DYNAMIC contents: %v", err)
return false
}
for len(d) > 0 {
var t elf.DynTag
switch f.Class {
case elf.ELFCLASS32:
t = elf.DynTag(f.ByteOrder.Uint32(d[:4]))
d = d[8:]
case elf.ELFCLASS64:
t = elf.DynTag(f.ByteOrder.Uint64(d[:8]))
d = d[16:]
}
if t == tag {
return true
}
}
return false
}
// The shared library contains a note containing the ABI hash that is mapped into
// memory and there is a local symbol called go.link.abihashbytes that points 16
// bytes into it.
func testABIHashNote(t *testing.T, f *elf.File, note *note) {
if note.section.Flags != elf.SHF_ALLOC {
t.Errorf("abi hash section has flags %v", note.section.Flags)
}
if !isOffsetLoaded(f, note.section.Offset) {
t.Errorf("abihash section not contained in PT_LOAD segment")
}
var hashbytes elf.Symbol
symbols, err := f.Symbols()
if err != nil {
t.Errorf("error reading symbols %v", err)
return
}
for _, sym := range symbols {
if sym.Name == "go.link.abihashbytes" {
hashbytes = sym
}
}
if hashbytes.Name == "" {
t.Errorf("no symbol called go.link.abihashbytes")
return
}
if elf.ST_BIND(hashbytes.Info) != elf.STB_LOCAL {
t.Errorf("%s has incorrect binding %v", hashbytes.Name, elf.ST_BIND(hashbytes.Info))
}
if f.Sections[hashbytes.Section] != note.section {
t.Errorf("%s has incorrect section %v", hashbytes.Name, f.Sections[hashbytes.Section].Name)
}
if hashbytes.Value-note.section.Addr != 16 {
t.Errorf("%s has incorrect offset into section %d", hashbytes.Name, hashbytes.Value-note.section.Addr)
}
}
func haveDynTag(file *elf.File, tag elf.DynTag) bool {
if section := file.Section(".dynamic"); section != nil {
reader := io.NewSectionReader(section, 0, int64(section.Size))
switch file.Machine {
case elf.EM_X86_64:
for {
var entry elf.Dyn64
if err := binary.Read(reader, binary.LittleEndian, &entry); err != io.EOF {
if elf.DynTag(entry.Tag) == tag {
return true
}
} else {
break
}
}
case elf.EM_386:
for {
var entry elf.Dyn32
if err := binary.Read(reader, binary.LittleEndian, &entry); err != io.EOF {
if elf.DynTag(entry.Tag) == tag {
return true
}
} else {
break
}
}
}
}
return false
}
func dump_symbols(file *elf.File) {
fmt.Printf("Symbols:\n")
symbols, _ := file.Symbols()
for _, e := range symbols {
if !strings.EqualFold(e.Name, "") {
fmt.Printf("\t%s\n", e.Name)
}
}
}
func producer(debugfile *elf.File, dwzfile *elf.File, debug_package string, debug_file string) []string {
var output []string
// iterate over all CUs present in debugfile
d, e := debugfile.DWARF() // increases memory usage by 2x to 3x!
if e != nil {
log.Println(e, debug_package, debug_file)
return output
}
reader := d.Reader()
for {
entry, err := reader.Next()
if err != nil {
log.Println(err, debug_file, debug_package)
break
}
if entry == nil {
break
}
if entry.Tag == dwarf.TagCompileUnit {
for _, f := range entry.Field {
if f.Attr == dwarf.AttrName {
switch f.Val.(type) {
case string:
output = append(output, f.Val.(string))
case dwarf.OffsetStrpAlt:
output = append(output, (string)(f.Val.(dwarf.OffsetStrpAlt)))
case dwarf.OffsetRefAlt:
log.Panic("DW_FORM_GNU_ref_alt handling missing for dwarf.AttrName ;(")
default:
panic("form unhandled for dwarf.AttrName, expect the unexpected ;(")
}
} else if f.Attr == dwarf.AttrProducer {
switch f.Val.(type) {
case string:
output = append(output, f.Val.(string))
case dwarf.OffsetStrpAlt:
output = append(output, dwzparser(dwzfile, (int64)(f.Val.(dwarf.OffsetStrpAlt)), debug_package, debug_file))
case dwarf.OffsetRefAlt:
log.Panic("DW_FORM_GNU_ref_alt handling missing for dwarf.AttrProducer ;(")
default:
panic("form unhandled for dwarf.AttrProducer, expect the unexpected ;(")
}
}
}
}
}
// log.Println(output)
return output
}
func getSectionData(f *elf.File, name string) []byte {
section := f.Section(name)
if section == nil {
log.Fatalf("failed getting section %s", name)
}
data, err := section.Data()
if err != nil {
log.Fatalf("failed getting section %s data: %s", name, err)
}
return data
}
func GetSymbols(e *elf.File) map[ds.Range]*ds.Symbol {
res := make(map[ds.Range]*ds.Symbol)
symbols, err := e.Symbols()
if err != nil {
log.WithFields(log.Fields{"error": err}).Info("Failed to Parse Symbols")
return res
}
for _, sym := range symbols {
sym_type := elfSymbolTypeToSymbolType(uint(sym.Info))
symbol := ds.NewSymbol(sym.Name, sym_type)
res[ds.NewRange(sym.Value, sym.Value+sym.Size)] = symbol
}
return res
}
func processGoInformation(f *elf.File) {
gosymtab := getSectionData(f, ".gosymtab")
gopclntab := getSectionData(f, ".gopclntab")
lineTable := gosym.NewLineTable(gopclntab, f.Section(".text").Addr)
table, err := gosym.NewTable(gosymtab, lineTable)
if err != nil {
log.Fatalf("failed making table: %s", err)
}
printSyms(table.Syms)
printFuncs(table.Funcs)
printFiles(table.Files)
}
func (dbp *Process) parseDebugLineInfo(exe *elf.File, wg *sync.WaitGroup) {
defer wg.Done()
if sec := exe.Section(".debug_line"); sec != nil {
debugLine, err := exe.Section(".debug_line").Data()
if err != nil {
fmt.Println("could not get .debug_line section", err)
os.Exit(1)
}
dbp.lineInfo = line.Parse(debugLine)
} else {
fmt.Println("could not find .debug_line section in binary")
os.Exit(1)
}
}
func (dbp *Process) parseDebugFrame(exe *elf.File, wg *sync.WaitGroup) {
defer wg.Done()
if sec := exe.Section(".debug_frame"); sec != nil {
debugFrame, err := exe.Section(".debug_frame").Data()
if err != nil {
fmt.Println("could not get .debug_frame section", err)
os.Exit(1)
}
dbp.frameEntries = frame.Parse(debugFrame)
} else {
fmt.Println("could not find .debug_frame section in binary")
os.Exit(1)
}
}
func dwzparser(dwzfile *elf.File, offset int64, debug_package string, debug_file string) string {
if section := dwzfile.Section(".debug_str"); section != nil {
reader := io.NewSectionReader(section, 0, int64(section.Size))
reader.Seek(offset, 1)
bufreader := bufio.NewReader(reader)
// http://golang.org/pkg/bufio/#Reader.ReadString
str, err := bufreader.ReadString('\x00')
if err != nil {
log.Println(err, debug_package, debug_file)
}
return strings.TrimSuffix(str, "\x00")
}
panic("dwzparser ran into problems ;(")
}
func canary(file *elf.File) string {
if symbols, e := file.Symbols(); e == nil {
for _, sym := range symbols {
if bytes.HasPrefix([]byte(sym.Name), []byte(STACK_CHK)) {
return ENABLED
}
}
}
if importedSymbols, e := file.ImportedSymbols(); e == nil {
for _, imp := range importedSymbols {
if bytes.HasPrefix([]byte(imp.Name), []byte(STACK_CHK)) {
return ENABLED
}
}
}
return DISABLED
}
func elfGoSyms(f *elf.File) (*gosym.Table, os.Error) {
text := f.Section(".text")
symtab := f.Section(".gosymtab")
pclntab := f.Section(".gopclntab")
if text == nil || symtab == nil || pclntab == nil {
return nil, nil
}
symdat, err := symtab.Data()
if err != nil {
return nil, err
}
pclndat, err := pclntab.Data()
if err != nil {
return nil, err
}
pcln := gosym.NewLineTable(pclndat, text.Addr)
tab, err := gosym.NewTable(symdat, pcln)
if err != nil {
return nil, err
}
return tab, nil
}
func (dbp *Process) obtainGoSymbols(exe *elf.File, wg *sync.WaitGroup) {
defer wg.Done()
var (
symdat []byte
pclndat []byte
err error
)
if sec := exe.Section(".gosymtab"); sec != nil {
symdat, err = sec.Data()
if err != nil {
fmt.Println("could not get .gosymtab section", err)
os.Exit(1)
}
}
if sec := exe.Section(".gopclntab"); sec != nil {
pclndat, err = sec.Data()
if err != nil {
fmt.Println("could not get .gopclntab section", err)
os.Exit(1)
}
}
pcln := gosym.NewLineTable(pclndat, exe.Section(".text").Addr)
tab, err := gosym.NewTable(symdat, pcln)
if err != nil {
fmt.Println("could not get initialize line table", err)
os.Exit(1)
}
dbp.goSymTable = tab
}
func blacklisted(file string, obj *elf.File) (bool, error) {
lib := regexp.MustCompile(`^.*/lib([\w-]+)\.so[\d.]*$`)
glcore := regexp.MustCompile(`libnvidia-e?glcore\.so`)
gldispatch := regexp.MustCompile(`libGLdispatch\.so`)
if m := lib.FindStringSubmatch(file); m != nil {
switch m[1] {
// Blacklist EGL/OpenGL libraries issued by other vendors
case "EGL":
fallthrough
case "GLESv1_CM":
fallthrough
case "GLESv2":
fallthrough
case "GL":
deps, err := obj.DynString(elf.DT_NEEDED)
if err != nil {
return false, err
}
for _, d := range deps {
if glcore.MatchString(d) || gldispatch.MatchString(d) {
return false, nil
}
}
return true, nil
// Blacklist TLS libraries using the old ABI (!= 2.3.99)
case "nvidia-tls":
const abi = 0x6300000003
s, err := obj.Section(".note.ABI-tag").Data()
if err != nil {
return false, err
}
return binary.LittleEndian.Uint64(s[24:]) != abi, nil
}
}
return false, nil
}
func printFileInformation(f *elf.File) {
printHeader(&f.FileHeader)
printSections(f.Sections)
printProgs(f.Progs)
printImportedLibraries(f.ImportedLibraries())
printSymbols(f.Symbols())
printImportedSymbols(f.ImportedSymbols())
}
func printDwarfInformation(f *elf.File) {
dwarf, err := f.DWARF()
if err != nil {
log.Printf("failed getting DWARF info: %s", err)
return
}
rd := dwarf.Reader()
for {
entry, err := rd.Next()
if err != nil {
log.Printf("failed getting next DWARF entry: %s", err)
return
}
if entry == nil {
// All done
return
}
log.Printf("got entry with tag: %s, and offset %d", entry.Tag, entry.Offset)
for _, field := range entry.Field {
log.Printf("\t%s: %v", field.Attr, field.Val)
}
}
}
func dump_dynstr(file *elf.File) {
fmt.Printf("DynStrings:\n")
dynstrs, _ := file.DynString(elf.DT_NEEDED)
for _, e := range dynstrs {
fmt.Printf("\t%s\n", e)
}
dynstrs, _ = file.DynString(elf.DT_SONAME)
for _, e := range dynstrs {
fmt.Printf("\t%s\n", e)
}
dynstrs, _ = file.DynString(elf.DT_RPATH)
for _, e := range dynstrs {
fmt.Printf("\t%s\n", e)
}
dynstrs, _ = file.DynString(elf.DT_RUNPATH)
for _, e := range dynstrs {
fmt.Printf("\t%s\n", e)
}
}
func parse(file string, f *elf.File, t *testing.T) (*elf.File, *Table) {
symdat, err := f.Section(".gosymtab").Data()
if err != nil {
f.Close()
t.Fatalf("reading %s gosymtab: %v", file, err)
}
pclndat, err := f.Section(".gopclntab").Data()
if err != nil {
f.Close()
t.Fatalf("reading %s gopclntab: %v", file, err)
}
pcln := NewLineTable(pclndat, f.Section(".text").Addr)
tab, err := NewTable(symdat, pcln)
if err != nil {
f.Close()
t.Fatalf("parsing %s gosymtab: %v", file, err)
}
return f, tab
}
func producer(debugfile *elf.File, dwzfile *elf.File, debug_package string, debug_file string) []string {
var output []string
// iterate over all CUs present in debugfile
d, e := debugfile.DWARF() // increases memory usage by 2x to 3x!
if e != nil {
log.Println(e, debug_package, debug_file)
return output
}
reader := d.Reader()
for {
entry, err := reader.Next()
if err != nil {
log.Println(err, debug_file, debug_package)
break
}
if entry == nil {
break
}
if entry.Tag == dwarf.TagCompileUnit {
for _, f := range entry.Field {
if f.Attr == dwarf.AttrName {
switch f.Val.(type) {
case string:
output = append(output, f.Val.(string))
default:
// distinguish between dwarf.OffsetStrpAlt, and dwarf.OffsetRefAlt
switch f.Class {
case dwarf.ClassStringAlt:
output = append(output, dwzparser(dwzfile, (int64)(f.Val.(int64)), debug_package, debug_file)) // this are filenames!
dummy := 0
_ = dummy
// panic("dwarf.ClassStringAlt is not handled currently in dwarf.AttrName, expect the unexpected ;(")
case dwarf.ClassReferenceAlt:
panic("dwarf.ClassReferenceAlt is not handled currently in dwarf.AttrName, expect the unexpected ;(")
default:
panic("form unhandled for dwarf.AttrName, expect the unexpected ;(")
}
}
} else if f.Attr == dwarf.AttrProducer {
switch f.Val.(type) {
case string:
output = append(output, f.Val.(string))
default:
// distinguish between dwarf.OffsetStrpAlt, and dwarf.OffsetRefAlt
switch f.Class {
case dwarf.ClassStringAlt:
output = append(output, dwzparser(dwzfile, (int64)(f.Val.(int64)), debug_package, debug_file))
case dwarf.ClassReferenceAlt:
panic("dwarf.ClassReferenceAlt is not handled currently in dwarf.AttrProducer, expect the unexpected ;(")
default:
panic("form unhandled for dwarf.AttrProducer, expect the unexpected ;(")
}
}
}
}
}
}
// log.Println(output)
return output
}