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#include "MachOProcessor.h"
#include "SharedCache.h"
using namespace BinaryNinja;
SharedCacheMachOProcessor::SharedCacheMachOProcessor(Ref<BinaryView> view, std::shared_ptr<VirtualMemory> vm)
{
m_view = view;
m_logger = new Logger("SharedCache.MachOProcessor", view->GetFile()->GetSessionId());
m_vm = std::move(vm);
// Adjust processor settings.
if (Ref<Settings> settings = m_view->GetLoadSettings(VIEW_NAME))
{
if (settings->Contains("loader.dsc.processFunctionStarts"))
m_applyFunctions = settings->Get<bool>("loader.dsc.processFunctionStarts", m_view);
}
}
void SharedCacheMachOProcessor::ApplyHeader(SharedCacheMachOHeader& header)
{
auto typeLibraryFromName = [&](const std::string& name) -> Ref<TypeLibrary> {
// Check to see if we have already loaded the type library.
if (auto typeLib = m_view->GetTypeLibrary(name))
return typeLib;
auto typeLibs = m_view->GetDefaultPlatform()->GetTypeLibrariesByName(name);
if (!typeLibs.empty())
return typeLibs.front();
return nullptr;
};
// Add a section for the header itself.
std::string headerSection = fmt::format("{}::__macho_header", header.identifierPrefix);
// TODO: Support mach_header (non 64bit)
uint64_t headerSectionSize = sizeof(mach_header_64) + header.ident.sizeofcmds;
m_view->AddUserSection(headerSection, header.textBase, headerSectionSize, ReadOnlyDataSectionSemantics);
ApplyHeaderSections(header);
ApplyHeaderDataVariables(header);
if (header.linkeditPresent && m_vm->IsAddressMapped(header.linkeditSegment.vmaddr))
{
if (m_applyFunctions && header.functionStartsPresent)
{
auto targetPlatform = m_view->GetDefaultPlatform();
auto functions = header.ReadFunctionTable(*m_vm);
for (const auto& func : functions)
m_view->AddFunctionForAnalysis(targetPlatform, func, false);
}
// Pull the available type library for the image we are loading, so we can apply known types.
auto typeLib = typeLibraryFromName(header.installName);
m_view->BeginBulkModifySymbols();
// TODO: Why does this need to only happen in linkeditSegment?
// Apply symbols from symbol table.
if (header.symtab.symoff != 0)
{
// Mach-O View symtab processing with
// a ton of stuff cut out so it can work
// NOTE: This table is read relative to the link edit segment file base.
const auto symbols = header.ReadSymbolTable(*m_view, *m_vm);
for (const auto& sym : symbols)
ApplySymbol(m_view, typeLib, sym.ToBNSymbol(*m_view));
}
// Apply symbols from export trie.
if (header.exportTriePresent)
{
// NOTE: This table is read relative to the link edit segment file base.
// TODO: Remove this and use the m_symbols in the cache?
const auto exportSymbols = header.ReadExportSymbolTrie(*m_vm);
for (const auto& sym : exportSymbols)
ApplySymbol(m_view, typeLib, sym.ToBNSymbol(*m_view));
}
m_view->EndBulkModifySymbols();
}
}
uint64_t SharedCacheMachOProcessor::ApplyHeaderSections(SharedCacheMachOHeader& header)
{
auto initSection = [&](const section_64& section, const std::string& sectionName) {
if (!section.size)
return false;
std::string type;
BNSectionSemantics semantics = DefaultSectionSemantics;
switch (section.flags & 0xff)
{
case S_REGULAR:
if (section.flags & S_ATTR_PURE_INSTRUCTIONS)
{
type = "PURE_CODE";
semantics = ReadOnlyCodeSectionSemantics;
}
else if (section.flags & S_ATTR_SOME_INSTRUCTIONS)
{
type = "CODE";
semantics = ReadOnlyCodeSectionSemantics;
}
else
{
type = "REGULAR";
}
break;
case S_ZEROFILL:
type = "ZEROFILL";
semantics = ReadWriteDataSectionSemantics;
break;
case S_CSTRING_LITERALS:
type = "CSTRING_LITERALS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_4BYTE_LITERALS:
type = "4BYTE_LITERALS";
break;
case S_8BYTE_LITERALS:
type = "8BYTE_LITERALS";
break;
case S_LITERAL_POINTERS:
type = "LITERAL_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_NON_LAZY_SYMBOL_POINTERS:
type = "NON_LAZY_SYMBOL_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_LAZY_SYMBOL_POINTERS:
type = "LAZY_SYMBOL_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_SYMBOL_STUBS:
type = "SYMBOL_STUBS";
semantics = ReadOnlyCodeSectionSemantics;
break;
case S_MOD_INIT_FUNC_POINTERS:
type = "MOD_INIT_FUNC_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_MOD_TERM_FUNC_POINTERS:
type = "MOD_TERM_FUNC_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_COALESCED:
type = "COALESCED";
break;
case S_GB_ZEROFILL:
type = "GB_ZEROFILL";
semantics = ReadWriteDataSectionSemantics;
break;
case S_INTERPOSING:
type = "INTERPOSING";
break;
case S_16BYTE_LITERALS:
type = "16BYTE_LITERALS";
break;
case S_DTRACE_DOF:
type = "DTRACE_DOF";
break;
case S_LAZY_DYLIB_SYMBOL_POINTERS:
type = "LAZY_DYLIB_SYMBOL_POINTERS";
semantics = ReadOnlyDataSectionSemantics;
break;
case S_THREAD_LOCAL_REGULAR:
type = "THREAD_LOCAL_REGULAR";
break;
case S_THREAD_LOCAL_ZEROFILL:
type = "THREAD_LOCAL_ZEROFILL";
break;
case S_THREAD_LOCAL_VARIABLES:
type = "THREAD_LOCAL_VARIABLES";
break;
case S_THREAD_LOCAL_VARIABLE_POINTERS:
type = "THREAD_LOCAL_VARIABLE_POINTERS";
break;
case S_THREAD_LOCAL_INIT_FUNCTION_POINTERS:
type = "THREAD_LOCAL_INIT_FUNCTION_POINTERS";
break;
default:
type = "UNKNOWN";
break;
}
if (strncmp(section.sectname, "__text", sizeof(section.sectname)) == 0)
semantics = ReadOnlyCodeSectionSemantics;
if (strncmp(section.sectname, "__const", sizeof(section.sectname)) == 0)
semantics = ReadOnlyDataSectionSemantics;
if (strncmp(section.sectname, "__data", sizeof(section.sectname)) == 0)
semantics = ReadWriteDataSectionSemantics;
if (strncmp(section.sectname, "__auth_got", sizeof(section.sectname)) == 0)
semantics = ReadOnlyDataSectionSemantics;
if (strncmp(section.segname, "__DATA_CONST", sizeof(section.segname)) == 0)
semantics = ReadOnlyDataSectionSemantics;
m_view->AddUserSection(sectionName, section.addr, section.size, semantics, type, section.align);
return true;
};
uint64_t addedSections = 0;
for (size_t i = 0; i < header.sections.size() && i < header.sectionNames.size(); i++)
{
if (initSection(header.sections[i], header.sectionNames[i]))
addedSections++;
}
return addedSections;
}
void SharedCacheMachOProcessor::ApplyHeaderDataVariables(SharedCacheMachOHeader& header)
{
// TODO: By using a binary reader we assume the sections have all been mapped.
// TODO: Maybe we should just use the virtual memory reader...
// TODO: We can define symbols and data variables even if there is no backing region FWIW
BinaryReader reader(m_view);
// TODO: Do we support non 64 bit header?
reader.Seek(header.textBase + sizeof(mach_header_64));
m_view->DefineDataVariable(header.textBase, Type::NamedType(m_view, QualifiedName("mach_header_64")));
m_view->DefineAutoSymbol(
new Symbol(DataSymbol, "__macho_header::" + header.identifierPrefix, header.textBase, LocalBinding));
auto applyLoadCommand = [&](uint64_t cmdAddr, const load_command& load) {
switch (load.cmd)
{
case LC_SEGMENT:
{
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("segment_command")));
reader.SeekRelative(5 * 8);
size_t numSections = reader.Read32();
reader.SeekRelative(4);
for (size_t j = 0; j < numSections; j++)
{
m_view->DefineDataVariable(reader.GetOffset(), Type::NamedType(m_view, QualifiedName("section")));
auto sectionSymName =
fmt::format("__macho_section::{}_[{}]", header.identifierPrefix, std::to_string(j));
auto sectionSym = new Symbol(DataSymbol, sectionSymName, reader.GetOffset(), LocalBinding);
m_view->DefineAutoSymbol(sectionSym);
reader.SeekRelative((8 * 8) + 4);
}
break;
}
case LC_SEGMENT_64:
{
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("segment_command_64")));
reader.SeekRelative(7 * 8);
size_t numSections = reader.Read32();
reader.SeekRelative(4);
for (size_t j = 0; j < numSections; j++)
{
m_view->DefineDataVariable(reader.GetOffset(), Type::NamedType(m_view, QualifiedName("section_64")));
auto sectionSymName =
fmt::format("__macho_section_64::{}_[{}]", header.identifierPrefix, std::to_string(j));
auto sectionSym = new Symbol(DataSymbol, sectionSymName, reader.GetOffset(), LocalBinding);
m_view->DefineAutoSymbol(sectionSym);
reader.SeekRelative(10 * 8);
}
break;
}
case LC_SYMTAB:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("symtab")));
break;
case LC_DYSYMTAB:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("dysymtab")));
break;
case LC_UUID:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("uuid")));
break;
case LC_ID_DYLIB:
case LC_LOAD_DYLIB:
case LC_REEXPORT_DYLIB:
case LC_LOAD_WEAK_DYLIB:
case LC_LOAD_UPWARD_DYLIB:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("dylib_command")));
if (load.cmdsize - 24 <= 150)
m_view->DefineDataVariable(
cmdAddr + 24, Type::ArrayType(Type::IntegerType(1, true), load.cmdsize - 24));
break;
case LC_CODE_SIGNATURE:
case LC_SEGMENT_SPLIT_INFO:
case LC_FUNCTION_STARTS:
case LC_DATA_IN_CODE:
case LC_DYLIB_CODE_SIGN_DRS:
case LC_DYLD_EXPORTS_TRIE:
case LC_DYLD_CHAINED_FIXUPS:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("linkedit_data")));
break;
case LC_ENCRYPTION_INFO:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("encryption_info")));
break;
case LC_VERSION_MIN_MACOSX:
case LC_VERSION_MIN_IPHONEOS:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("version_min")));
break;
case LC_DYLD_INFO:
case LC_DYLD_INFO_ONLY:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("dyld_info")));
break;
default:
m_view->DefineDataVariable(cmdAddr, Type::NamedType(m_view, QualifiedName("load_command")));
break;
}
};
try
{
for (size_t i = 0; i < header.ident.ncmds; i++)
{
load_command load {};
uint64_t curOffset = reader.GetOffset();
load.cmd = reader.Read32();
load.cmdsize = reader.Read32();
applyLoadCommand(curOffset, load);
m_view->DefineAutoSymbol(new Symbol(DataSymbol,
"__macho_load_command::" + header.identifierPrefix + "_[" + std::to_string(i) + "]", curOffset,
LocalBinding));
uint64_t nextOffset = curOffset + load.cmdsize;
reader.Seek(nextOffset);
}
}
catch (ReadException&)
{
m_logger->LogError("Error when applying Mach-O header types at %llx", header.textBase);
}
}
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