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support for removing LC_DYLD_FIXUPS_CHAINS data

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This commit is contained in:
nganhkhoa 2023-06-05 15:55:21 +07:00
parent 7592cfd2dd
commit 6d757108a7
1 changed files with 22 additions and 36 deletions
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58
macho-go/pkg/ios/macho/edit.go
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@ -278,40 +278,6 @@ func (mc *MachoContext) RemoveBindSymbols() {
} else {
mc.removeBindSymbolsLegacy()
}
}
func (mc *MachoContext) removeBindSymbolsModern() {
calculateHash := func(name string) uint32 {
var h uint32 = 0x811c9dc5
for _, s := range name {
h ^= uint32(s)
h *= 0x01000193
}
return h
}
// due to some limitations when design this tool
// we write the c code to stdout lol
fmt.Println("struct imported_symbol {const char* name; const char* lib; uint32_t hash; uint64_t address;};")
fmt.Println("struct imported_symbol imported_table[] = {")
count := 0
for _, symbol := range mc.CollectBindSymbols() {
count += 1
dylib_hash := calculateHash(symbol.Dylib())
fmt.Printf("{\"%s\", \"%s\", 0x%x, 0x%x},\n",
symbol.Name(), symbol.Dylib(), dylib_hash, symbol.Address());
mc.file.WriteAt(make([]byte, 8), int64(symbol.file_address))
}
fmt.Println("};")
fmt.Printf("uint32_t nimports = %d;\n", count);
}
func (mc *MachoContext) removeBindSymbolsLegacy() {
start := mc.dyldinfo.lazy_bind_off
size := mc.dyldinfo.lazy_bind_size
// set lazy opcodes to 0x00 == DO_BIND
// but no symbol state to bind
mc.file.WriteAt(make([]byte, size), int64(start))
calculateHash := func(name string) uint32 {
var h uint32 = 0x811c9dc5
@ -334,12 +300,32 @@ func (mc *MachoContext) removeBindSymbolsLegacy() {
count += 1
dylib_hash := calculateHash(symbol.Dylib())
seg := mc.segments[symbol.segment]
offset := symbol.address - seg.Vmaddr()
var offset uint64
if symbol.address >= seg.Vmaddr() {
// this is virtual address
offset = symbol.address - seg.Vmaddr()
} else {
// this is file address
offset = symbol.address - seg.Fileoff()
}
fmt.Printf("{\"%s\", \"%s\", 0x%x, 0x%x, 0x%x},\n",
symbol.Name(), symbol.Dylib(), dylib_hash, symbol.segment, offset);
mc.file.WriteAt(make([]byte, 8), int64(seg.Fileoff() + offset))
mc.file.WriteAt(make([]byte, 8), int64(symbol.file_address))
}
fmt.Println("};")
fmt.Printf("uint32_t nimports = %d;\n", count);
}
func (mc *MachoContext) removeBindSymbolsModern() {
}
func (mc *MachoContext) removeBindSymbolsLegacy() {
start := mc.dyldinfo.lazy_bind_off
size := mc.dyldinfo.lazy_bind_size
// set lazy opcodes to 0x00 == DO_BIND
// but no symbol state to bind
mc.file.WriteAt(make([]byte, size), int64(start))
}