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feat: add cmd String methods to more LCs and improve summary output
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@blacktop
blacktop committed Jun 28, 2020
1 parent 20274ff commit 554515a
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Showing 3 changed files with 168 additions and 18 deletions.
151 changes: 140 additions & 11 deletions cmds.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -387,6 +387,15 @@ type Symtab struct {
Syms []Symbol
}

func (s *Symtab) String() string {
return fmt.Sprintf("Symbol offset=0x%08X, Num Syms: %d, String offset=0x%08X-0x%08X", s.Symoff, s.Nsyms, s.Stroff, s.Stroff+s.Strsize)
}
func (s *Symtab) Copy() *Symtab {
return &Symtab{SymtabCmd: s.SymtabCmd, Syms: append([]Symbol{}, s.Syms...)}
}
func (s *Symtab) LoadSize(t *FileTOC) uint32 {
return uint32(unsafe.Sizeof(types.SymtabCmd{}))
}
func (s *Symtab) Put(b []byte, o binary.ByteOrder) int {
o.PutUint32(b[0*4:], uint32(s.LoadCmd))
o.PutUint32(b[1*4:], s.Len)
Expand All @@ -397,14 +406,6 @@ func (s *Symtab) Put(b []byte, o binary.ByteOrder) int {
return 6 * 4
}

func (s *Symtab) String() string { return fmt.Sprintf("Symtab %#v", s.SymtabCmd) }
func (s *Symtab) Copy() *Symtab {
return &Symtab{SymtabCmd: s.SymtabCmd, Syms: append([]Symbol{}, s.Syms...)}
}
func (s *Symtab) LoadSize(t *FileTOC) uint32 {
return uint32(unsafe.Sizeof(types.SymtabCmd{}))
}

// A Symbol is a Mach-O 32-bit or 64-bit symbol table entry.
type Symbol struct {
Name string
Expand Down Expand Up @@ -434,6 +435,11 @@ type Symbol struct {
type UnixThread struct {
LoadBytes
types.UnixThreadCmd
EntryPoint uint64
}

func (u *UnixThread) String() string {
return fmt.Sprintf("Entry Point: 0x%016x", u.EntryPoint)
}

// TODO: LC_LOADFVMLIB 0x6 /* load a specified fixed VM shared library */
Expand All @@ -453,6 +459,17 @@ type Dysymtab struct {
IndirectSyms []uint32 // indices into Symtab.Syms
}

func (d *Dysymtab) String() string {
// TODO make this like jtool
// 1 local symbols at index 0
// 29 external symbols at index 1
// 709 undefined symbols at index 30
// No TOC
// No modtab
// 1149 Indirect symbols at offset 0x1695f0
return fmt.Sprintf("%d Indirect symbols at offset 0x%08X", d.Nindirectsyms, d.Indirectsymoff)
}

/*******************************************************************************
* LC_ID_DYLIB, LC_LOAD_{,WEAK_}DYLIB,LC_REEXPORT_DYLIB
*******************************************************************************/
Expand Down Expand Up @@ -531,6 +548,10 @@ type SubClient struct {
// A WeakDylib represents a Mach-O load weak dynamic library command.
type WeakDylib Dylib

func (d *WeakDylib) String() string {
return fmt.Sprintf("%s (%s)", d.Name, d.CurrentVersion)
}

/*******************************************************************************
* LC_ROUTINES_64
*******************************************************************************/
Expand Down Expand Up @@ -595,6 +616,12 @@ type CodeSignature struct {
CMSSignature types.CsBlob
}

func (c *CodeSignature) String() string {
// TODO: fix this once codesigs are done
// return fmt.Sprintf("offset=0x%08x-0x%08x, size=%d, ID: %s", c.Offset, c.Offset+c.Size, c.Size, c.ID)
return fmt.Sprintf("offset=0x%08x-0x%08x, size=%5d", c.Offset, c.Offset+c.Size, c.Size)
}

/*******************************************************************************
* LC_SEGMENT_SPLIT_INFO
*******************************************************************************/
Expand Down Expand Up @@ -635,7 +662,99 @@ type DyldInfo struct {
ExportSize uint32 // size of export info
}

// TODO: LC_DYLD_INFO_ONLY (0x22|LC_REQ_DYLD) /* compressed dyld information only */
func (d *DyldInfo) String() string {
return fmt.Sprintf(
"\n"+
"\t\tRebase info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tBind info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tWeak info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tLazy info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tExport info: %5d bytes at offset: 0x%08X -> 0x%08X",
d.RebaseSize, d.RebaseOff, d.RebaseOff+d.RebaseSize,
d.BindSize, d.BindOff, d.BindOff+d.BindSize,
d.WeakBindSize, d.WeakBindOff, d.WeakBindOff+d.WeakBindSize,
d.LazyBindSize, d.LazyBindOff, d.LazyBindOff+d.LazyBindSize,
d.ExportSize, d.ExportOff, d.ExportOff+d.ExportSize,
)
}
func (d *DyldInfo) Copy() *DyldInfo {
return &DyldInfo{DyldInfoCmd: d.DyldInfoCmd}
}
func (d *DyldInfo) LoadSize(t *FileTOC) uint32 {
return uint32(unsafe.Sizeof(types.UUIDCmd{}))
}
func (d *DyldInfo) Put(b []byte, o binary.ByteOrder) int {
o.PutUint32(b[0*4:], uint32(d.LoadCmd))
o.PutUint32(b[1*4:], d.Len)
o.PutUint32(b[2*4:], d.RebaseOff)
o.PutUint32(b[3*4:], d.RebaseSize)
o.PutUint32(b[4*4:], d.BindOff)
o.PutUint32(b[5*4:], d.BindSize)
o.PutUint32(b[6*4:], d.WeakBindOff)
o.PutUint32(b[7*4:], d.WeakBindSize)
o.PutUint32(b[8*4:], d.LazyBindOff)
o.PutUint32(b[9*4:], d.LazyBindSize)
o.PutUint32(b[10*4:], d.ExportOff)
o.PutUint32(b[11*4:], d.ExportSize)
return int(d.Len)
}

/*******************************************************************************
* LC_DYLD_INFO
*******************************************************************************/

// DyldInfoOnly is compressed dyld information only
type DyldInfoOnly struct {
LoadBytes
types.DyldInfoOnlyCmd
RebaseOff uint32 // file offset to rebase info
RebaseSize uint32 // size of rebase info
BindOff uint32 // file offset to binding info
BindSize uint32 // size of binding info
WeakBindOff uint32 // file offset to weak binding info
WeakBindSize uint32 // size of weak binding info
LazyBindOff uint32 // file offset to lazy binding info
LazyBindSize uint32 // size of lazy binding info
ExportOff uint32 // file offset to export info
ExportSize uint32 // size of export info
}

func (d *DyldInfoOnly) String() string {
return fmt.Sprintf(
"\n"+
"\t\tRebase info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tBind info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tWeak info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tLazy info: %5d bytes at offset: 0x%08X -> 0x%08X\n"+
"\t\tExport info: %5d bytes at offset: 0x%08X -> 0x%08X",
d.RebaseSize, d.RebaseOff, d.RebaseOff+d.RebaseSize,
d.BindSize, d.BindOff, d.BindOff+d.BindSize,
d.WeakBindSize, d.WeakBindOff, d.WeakBindOff+d.WeakBindSize,
d.LazyBindSize, d.LazyBindOff, d.LazyBindOff+d.LazyBindSize,
d.ExportSize, d.ExportOff, d.ExportOff+d.ExportSize,
)
}
func (d *DyldInfoOnly) Copy() *DyldInfoOnly {
return &DyldInfoOnly{DyldInfoOnlyCmd: d.DyldInfoOnlyCmd}
}
func (d *DyldInfoOnly) LoadSize(t *FileTOC) uint32 {
return uint32(unsafe.Sizeof(types.UUIDCmd{}))
}
func (d *DyldInfoOnly) Put(b []byte, o binary.ByteOrder) int {
o.PutUint32(b[0*4:], uint32(d.LoadCmd))
o.PutUint32(b[1*4:], d.Len)
o.PutUint32(b[2*4:], d.RebaseOff)
o.PutUint32(b[3*4:], d.RebaseSize)
o.PutUint32(b[4*4:], d.BindOff)
o.PutUint32(b[5*4:], d.BindSize)
o.PutUint32(b[6*4:], d.WeakBindOff)
o.PutUint32(b[7*4:], d.WeakBindSize)
o.PutUint32(b[8*4:], d.LazyBindOff)
o.PutUint32(b[9*4:], d.LazyBindSize)
o.PutUint32(b[10*4:], d.ExportOff)
o.PutUint32(b[11*4:], d.ExportSize)
return int(d.Len)
}

/*******************************************************************************
* LC_LOAD_UPWARD_DYLIB
Expand Down Expand Up @@ -674,13 +793,17 @@ type VersionMinIphoneos struct {
type FunctionStarts struct {
LoadBytes
types.FunctionStartsCmd
// Offset uint32
// Size uint32
Offset uint32
Size uint32
StartOffset uint64
NextFuncOffsets []uint64
VMAddrs []uint64
}

func (f *FunctionStarts) String() string {
return fmt.Sprintf("offset=0x%08x-0x%08x, size=%5d, count=%d", f.Offset, f.Offset+f.Size, f.Size, len(f.VMAddrs))
}

// TODO: LC_DYLD_ENVIRONMENT 0x27 /* string for dyld to treat
// like environment variable */

Expand Down Expand Up @@ -720,9 +843,15 @@ func (e *EntryPoint) Put(b []byte, o binary.ByteOrder) int {
type DataInCode struct {
LoadBytes
types.DataInCodeCmd
Offset uint32
Size uint32
Entries []types.DataInCodeEntry
}

func (d *DataInCode) String() string {
return fmt.Sprintf("offset=0x%08x-0x%08x, size=%5d, entries=%d", d.Offset, d.Offset+d.Size, d.Size, len(d.Entries))
}

/*******************************************************************************
* LC_SOURCE_VERSION
*******************************************************************************/
Expand Down
33 changes: 26 additions & 7 deletions file.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -48,14 +48,18 @@ func (t *FileTOC) String() string {

for i, l := range t.Loads {
if s, ok := l.(*Segment); ok {
fTocStr += fmt.Sprintf("%02d: %s, Segment %s, offset=0x%x, filesz=%d, addr=0x%x, memsz=%d, nsect=%d\n", i, s.Command(), s.Name,
s.Offset, s.Filesz, s.Addr, s.Memsz, s.Nsect)
fTocStr += fmt.Sprintf("%02d: %s offset=0x%08x-0x%08x, addr=0x%09x-0x%09x\t%s\n", i, s.Command(), s.Offset, s.Offset+s.Filesz, s.Addr, s.Addr+s.Memsz, s.Name)
for j := uint32(0); j < s.Nsect; j++ {
c := t.Sections[j+s.Firstsect]
fTocStr += fmt.Sprintf(" %s.%s\toffset=0x%x, size=%d, addr=0x%x, nreloc=%d\n", s.Name, c.Name, c.Offset, c.Size, c.Addr, c.Nreloc)
secFlags := ""
if !c.Flags.IsRegular() {
secFlags = fmt.Sprintf("(%s)", c.Flags)
}
fTocStr += fmt.Sprintf("\toffset=0x%08x-0x%08x, addr=0x%09x-0x%09x\t\t%s.%s\t%s\t%s\n", c.Offset, uint64(c.Offset)+c.Size, c.Addr, c.Addr+c.Size, s.Name, c.Name, secFlags, c.Flags.AttributesString())
// fTocStr += fmt.Sprintf(" %s.%s\toffset=0x%x, size=%d, addr=0x%x, nreloc=%d\n", s.Name, c.Name, c.Offset, c.Size, c.Addr, c.Nreloc)
}
} else {
fTocStr += fmt.Sprintf("%02d: %s\t%v\n", i, l.Command(), l)
fTocStr += fmt.Sprintf("%02d: %s%s%v\n", i, l.Command(), strings.Repeat(" ", 28-len(l.Command().String())), l)
}
}
if t.SizeCommands != t.LoadSize() {
Expand Down Expand Up @@ -451,6 +455,14 @@ func NewFile(r io.ReaderAt, loads ...types.LoadCmd) (*File, error) {
l := new(UnixThread)
l.LoadBytes = LoadBytes(cmddat)
l.LoadCmd = cmd
if ut.Flavor == 6 {
regs := make([]uint64, ut.Count/2)
if err := binary.Read(b, bo, &regs); err != nil {
return nil, err
}
// this is to get the program counter register
l.EntryPoint = regs[len(regs)-2]
}
f.Loads[i] = l
// TODO: case types.LcLoadfvmlib:
// TODO: case types.LcIdfvmlib:
Expand Down Expand Up @@ -738,8 +750,8 @@ func NewFile(r io.ReaderAt, loads ...types.LoadCmd) (*File, error) {
}
l := new(FunctionStarts)
l.LoadCmd = cmd
// l.Offset = led.Offset
// l.Size = led.Size
l.Offset = led.Offset
l.Size = led.Size
l.LoadBytes = LoadBytes(cmddat)
ldat := make([]byte, led.Size)
if _, err := r.ReadAt(ldat, int64(led.Offset)); err != nil {
Expand Down Expand Up @@ -792,8 +804,10 @@ func NewFile(r io.ReaderAt, loads ...types.LoadCmd) (*File, error) {
}
l := new(DataInCode)
l.LoadCmd = cmd
// TODO: finish parsing Dice entries
// var e DataInCodeEntry

l.Offset = led.Offset
l.Size = led.Size
l.LoadBytes = LoadBytes(cmddat)
f.Loads[i] = l
case types.LC_SOURCE_VERSION:
Expand Down Expand Up @@ -959,6 +973,11 @@ func (f *File) parseSymtab(symdat, strtab, cmddat []byte, hdr *types.SymtabCmd,
}
st := new(Symtab)
st.LoadBytes = LoadBytes(cmddat)
st.Symoff = hdr.Symoff
st.Nsyms = hdr.Nsyms
st.Stroff = hdr.Stroff
st.Strsize = hdr.Strsize
st.Len = hdr.Len
st.Syms = symtab
return st, nil
}
Expand Down
2 changes: 2 additions & 0 deletions types/commands.go
View file
Original file line number Diff line number Diff line change
Expand Up @@ -152,6 +152,8 @@ type Thread struct {
type UnixThreadCmd struct {
LoadCmd // LC_UNIXTHREAD
Len uint32
Flavor uint32
Count uint32
}

// A LoadFvmLibCmd is a Mach-O load a specified fixed VM shared library command.
Expand Down

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