Skip to content
This repository has been archived by the owner on Apr 21, 2019. It is now read-only.

Commit

Permalink
Merge pull request #9 from 0xced/patch-baseProperties
Browse files Browse the repository at this point in the history 
Patch class_ro_t baseProperties
  • Loading branch information
@kennytm
kennytm committed Mar 23, 2013
2 parents 0cc8095 + 2cfd25e commit 2e21aa4
Showing 1 changed file with 35 additions and 29 deletions.
64 changes: 35 additions & 29 deletions dyld_decache.cpp
View file
Expand Up @@ -326,6 +326,11 @@ struct method_t {
uint32_t imp;
};

struct property_t {
uint32_t name;
uint32_t attributes;
};

struct protocol_t {
uint32_t isa;
uint32_t name;
Expand Down Expand Up @@ -690,7 +695,7 @@ class DecachingFile : public MachOFile {
std::vector<FileoffFixup> _fixups;
std::vector<segment_command> _new_segments;
ExtraStringRepository _extra_text, _extra_data;
std::vector<uint32_t> _entsize12_patches, _nullify_patches;
std::vector<uint32_t> _nullify_patches;
ExtraBindRepository _extra_bind;

private:
Expand Down Expand Up @@ -889,7 +894,8 @@ class DecachingFile : public MachOFile {
return std::make_pair(-1, ~0u);
}

void prepare_patch_objc_methods(uint32_t method_vmaddr, uint32_t override_vmaddr);
template <typename T>
void prepare_patch_objc_list(uint32_t list_vmaddr, uint32_t override_vmaddr);
void prepare_objc_extrastr(const segment_command* segcmd);

void get_address_info(uint32_t vmaddr, std::string* p_name, int* p_libord) const;
Expand All @@ -907,7 +913,6 @@ class DecachingFile : public MachOFile {
_extra_text.foreach_entry(this, &DecachingFile::patch_objc_sects_callback);
_extra_data.foreach_entry(this, &DecachingFile::patch_objc_sects_callback);

this->patch_objc_sects_callback(NULL, 0, sizeof(method_t), _entsize12_patches);
this->patch_objc_sects_callback(NULL, 0, 0, _nullify_patches);

if (_imageinfo_address) {
Expand Down Expand Up @@ -1423,31 +1428,30 @@ void DecachingFile::add_extlink_to(uint32_t vmaddr, uint32_t override_vmaddr) {
_nullify_patches.push_back(override_vmaddr);
}

void DecachingFile::prepare_patch_objc_methods(uint32_t method_vmaddr, uint32_t override_vmaddr) {
if (!method_vmaddr)
template <typename T>
void DecachingFile::prepare_patch_objc_list(uint32_t list_vmaddr, uint32_t override_vmaddr) {
if (!list_vmaddr)
return;

off_t method_offset = _context->from_vmaddr(method_vmaddr);
_context->_f->seek(method_offset);
bool wrong_entsize = _context->_f->copy_data<uint32_t>() != sizeof(method_t);
off_t offset = _context->from_vmaddr(list_vmaddr);
_context->_f->seek(offset);
uint32_t entsize = _context->_f->copy_data<uint32_t>() & ~(uint32_t)3;
uint32_t count = _context->_f->copy_data<uint32_t>();

if (!this->contains_address(method_vmaddr)) {
method_vmaddr = _extra_data.next_vmaddr();
size_t size = 8 + sizeof(method_t)*count;
_extra_data.insert(_context->_f->peek_data_at<char>(method_offset), size, override_vmaddr);
}
if (entsize != sizeof(T))
throw TRException("DecachingFile::prepare_patch_objc_list():\n\tWrong entsize: %u instead of %lu\n", entsize, sizeof(T));

// add the patch to make sure the method_t's entsize is 12.
// (this causes class-dump-3.3.3 to raise an exception)
if (wrong_entsize)
_entsize12_patches.push_back(method_vmaddr);
if (!this->contains_address(list_vmaddr)) {
list_vmaddr = _extra_data.next_vmaddr();
size_t size = 8 + sizeof(T)*count;
_extra_data.insert(_context->_f->peek_data_at<char>(offset), size, override_vmaddr);
}

const method_t* methods = _context->_f->peek_data<method_t>();
const T* objects = _context->_f->peek_data<T>();
for (uint32_t j = 0; j < count; ++ j) {
if (!this->contains_address(methods[j].name)) {
const char* the_string = _context->peek_char_at_vmaddr(methods[j].name);
_extra_text.insert(the_string, method_vmaddr + 8 + sizeof(method_t)*j);
if (!this->contains_address(objects[j].name)) {
const char* the_string = _context->peek_char_at_vmaddr(objects[j].name);
_extra_text.insert(the_string, list_vmaddr + 8 + sizeof(T)*j);
}
}
}
Expand All @@ -1472,32 +1476,34 @@ void DecachingFile::prepare_objc_extrastr(const segment_command* segcmd) {
const class_t* class_obj = reinterpret_cast<const class_t*>(_context->peek_char_at_vmaddr(class_vmaddr));
this->add_extlink_to(class_obj->superclass, class_vmaddr + offsetof(class_t, superclass));
const class_ro_t* class_data = reinterpret_cast<const class_ro_t*>(_context->peek_char_at_vmaddr(class_obj->data));
this->prepare_patch_objc_methods(class_data->baseMethods, class_obj->data + offsetof(class_ro_t, baseMethods));
this->prepare_patch_objc_list<method_t>(class_data->baseMethods, class_obj->data + offsetof(class_ro_t, baseMethods));
this->prepare_patch_objc_list<property_t>(class_data->baseProperties, class_obj->data + offsetof(class_ro_t, baseProperties));

const class_t* metaclass_obj = reinterpret_cast<const class_t*>(_context->peek_char_at_vmaddr(class_obj->isa));
this->add_extlink_to(metaclass_obj->isa, class_obj->isa + offsetof(class_t, isa));
this->add_extlink_to(metaclass_obj->superclass, class_obj->isa + offsetof(class_t, superclass));
const class_ro_t* metaclass_data = reinterpret_cast<const class_ro_t*>(_context->peek_char_at_vmaddr(metaclass_obj->data));
this->prepare_patch_objc_methods(metaclass_data->baseMethods, metaclass_obj->data + offsetof(class_ro_t, baseMethods));
this->prepare_patch_objc_list<method_t>(metaclass_data->baseMethods, metaclass_obj->data + offsetof(class_ro_t, baseMethods));
this->prepare_patch_objc_list<property_t>(metaclass_data->baseProperties, metaclass_obj->data + offsetof(class_ro_t, baseProperties));
}
} else if (streq(sect.sectname, "__objc_protolist")) {
const uint32_t* protos = _context->_f->peek_data_at<uint32_t>(sect.offset);
for (uint32_t j = 0; j < sect.size/4; ++ j) {
uint32_t proto_vmaddr = protos[j];
const protocol_t* proto_obj = reinterpret_cast<const protocol_t*>(_context->peek_char_at_vmaddr(proto_vmaddr));
this->prepare_patch_objc_methods(proto_obj->instanceMethods, proto_vmaddr + offsetof(protocol_t, instanceMethods));
this->prepare_patch_objc_methods(proto_obj->classMethods, proto_vmaddr + offsetof(protocol_t, classMethods));
this->prepare_patch_objc_methods(proto_obj->optionalInstanceMethods, proto_vmaddr + offsetof(protocol_t, optionalInstanceMethods));
this->prepare_patch_objc_methods(proto_obj->optionalClassMethods, proto_vmaddr + offsetof(protocol_t, optionalClassMethods));
this->prepare_patch_objc_list<method_t>(proto_obj->instanceMethods, proto_vmaddr + offsetof(protocol_t, instanceMethods));
this->prepare_patch_objc_list<method_t>(proto_obj->classMethods, proto_vmaddr + offsetof(protocol_t, classMethods));
this->prepare_patch_objc_list<method_t>(proto_obj->optionalInstanceMethods, proto_vmaddr + offsetof(protocol_t, optionalInstanceMethods));
this->prepare_patch_objc_list<method_t>(proto_obj->optionalClassMethods, proto_vmaddr + offsetof(protocol_t, optionalClassMethods));
}
} else if (streq(sect.sectname, "__objc_catlist")) {
const uint32_t* cats = _context->_f->peek_data_at<uint32_t>(sect.offset);
for (uint32_t j = 0; j < sect.size/4; ++ j) {
uint32_t cat_vmaddr = cats[j];
const category_t* cat_obj = reinterpret_cast<const category_t*>(_context->peek_char_at_vmaddr(cat_vmaddr));
this->add_extlink_to(cat_obj->cls, cat_vmaddr + offsetof(category_t, cls));
this->prepare_patch_objc_methods(cat_obj->instanceMethods, cat_vmaddr + offsetof(category_t, instanceMethods));
this->prepare_patch_objc_methods(cat_obj->classMethods, cat_vmaddr + offsetof(category_t, classMethods));
this->prepare_patch_objc_list<method_t>(cat_obj->instanceMethods, cat_vmaddr + offsetof(category_t, instanceMethods));
this->prepare_patch_objc_list<method_t>(cat_obj->classMethods, cat_vmaddr + offsetof(category_t, classMethods));
}
} else if (streq(sect.sectname, "__objc_imageinfo")) {
_imageinfo_address = sect.addr + 4;
Expand Down

0 comments on commit 2e21aa4

Please sign in to comment.