ImageLoaderMachO.h   [plain text]


/* -*- mode: C++; c-basic-offset: 4; tab-width: 4 -*-
 *
 * Copyright (c) 2004-2009 Apple Inc. All rights reserved.
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 * 
 * This file contains Original Code and/or Modifications of Original Code
 * as defined in and that are subject to the Apple Public Source License
 * Version 2.0 (the 'License'). You may not use this file except in
 * compliance with the License. Please obtain a copy of the License at
 * http://www.opensource.apple.com/apsl/ and read it before using this
 * file.
 * 
 * The Original Code and all software distributed under the License are
 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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#ifndef __IMAGELOADERMACHO__
#define __IMAGELOADERMACHO__

#include <stdint.h> 
#include <mach-o/loader.h> 
#include <mach-o/nlist.h> 

#include "ImageLoader.h"
#include "mach-o/dyld_images.h"


//
// ImageLoaderMachO is a subclass of ImageLoader which loads mach-o format files.
//
//
class ImageLoaderMachO : public ImageLoader {
public:
	static ImageLoader*					instantiateMainExecutable(const macho_header* mh, uintptr_t slide, const char* path, const LinkContext& context);
	static ImageLoader*					instantiateFromFile(const char* path, int fd, const uint8_t firstPage[4096], uint64_t offsetInFat, 
															uint64_t lenInFat, const struct stat& info, const LinkContext& context);
	static ImageLoader*					instantiateFromCache(const macho_header* mh, const char* path, long slide, const struct stat& info, const LinkContext& context);
	static ImageLoader*					instantiateFromMemory(const char* moduleName, const macho_header* mh, uint64_t len, const LinkContext& context);


	bool								inSharedCache() const { return fInSharedCache; }
	const char*							getInstallPath() const;
	virtual void*						getMain() const;
	virtual const struct mach_header*   machHeader() const;
	virtual uintptr_t					getSlide() const;
	virtual const void*					getEnd() const;
	virtual bool						hasCoalescedExports() const;
	virtual const Symbol*				findExportedSymbol(const char* name, bool searchReExports, const ImageLoader** foundIn) const;
	virtual uintptr_t					getExportedSymbolAddress(const Symbol* sym, const LinkContext& context, 
																const ImageLoader* requestor, bool runResolver) const;
	virtual DefinitionFlags				getExportedSymbolInfo(const Symbol* sym) const;
	virtual const char*					getExportedSymbolName(const Symbol* sym) const;
	virtual uint32_t					getExportedSymbolCount() const;
	virtual const Symbol*				getIndexedExportedSymbol(uint32_t index) const;
	virtual uint32_t					getImportedSymbolCount() const;
	virtual const Symbol*				getIndexedImportedSymbol(uint32_t index) const;
	virtual ReferenceFlags				getImportedSymbolInfo(const Symbol* sym) const;
	virtual const char*					getImportedSymbolName(const Symbol* sym) const;
	virtual bool						isBundle() const;
	virtual bool						isDylib() const;
	virtual bool						isExecutable() const;
	virtual bool						isPositionIndependentExecutable() const;
	virtual bool						forceFlat() const;
	virtual bool						participatesInCoalescing() const;
	virtual const char*					findClosestSymbol(const void* addr, const void** closestAddr) const = 0;
	virtual	void						initializeCoalIterator(CoalIterator&, unsigned int loadOrder) = 0;
	virtual	bool						incrementCoalIterator(CoalIterator&) = 0;
	virtual	uintptr_t					getAddressCoalIterator(CoalIterator&, const LinkContext& contex) = 0;
	virtual	void						updateUsesCoalIterator(CoalIterator&, uintptr_t newAddr, ImageLoader* target, const LinkContext& context) = 0;
	virtual uintptr_t					doBindLazySymbol(uintptr_t* lazyPointer, const LinkContext& context) = 0;
	virtual uintptr_t					doBindFastLazySymbol(uint32_t lazyBindingInfoOffset, const LinkContext& context, void (*lock)(), void (*unlock)()) = 0;
	virtual void						doTermination(const LinkContext& context);
	virtual bool						needsInitialization();
	virtual bool						getSectionContent(const char* segmentName, const char* sectionName, void** start, size_t* length);
	virtual void						getUnwindInfo(dyld_unwind_sections* info);
	virtual bool						findSection(const void* imageInterior, const char** segmentName, const char** sectionName, size_t* sectionOffset);
	virtual bool						usablePrebinding(const LinkContext& context) const;
	virtual unsigned int				segmentCount() const;
	virtual const char*					segName(unsigned int) const;
	virtual uintptr_t					segSize(unsigned int) const;
	virtual uintptr_t					segFileSize(unsigned int) const;
	virtual bool						segHasTrailingZeroFill(unsigned int);
	virtual uintptr_t					segFileOffset(unsigned int) const;
	virtual bool						segReadable(unsigned int) const;
	virtual bool						segWriteable(unsigned int) const;
	virtual bool						segExecutable(unsigned int) const;
	virtual bool						segUnaccessible(unsigned int) const;
	virtual bool						segHasPreferredLoadAddress(unsigned int) const;
	virtual uintptr_t					segActualLoadAddress(unsigned int) const;
	virtual uintptr_t					segPreferredLoadAddress(unsigned int) const;
	virtual uintptr_t					segActualEndAddress(unsigned int) const;
	virtual void						registerInterposing();
			
	
	static void							printStatistics(unsigned int imageCount, const InitializerTimingList&);
	
protected:
						ImageLoaderMachO(const ImageLoaderMachO&);
						ImageLoaderMachO(const macho_header* mh, const char* path, unsigned int segCount,
																	uint32_t segOffsets[], unsigned int libCount);
	virtual				~ImageLoaderMachO() {}

	void				operator=(const ImageLoaderMachO&);

	virtual void						setDyldInfo(const struct dyld_info_command*) = 0;
	virtual void						setSymbolTableInfo(const macho_nlist*, const char*, const dysymtab_command*) = 0;
	virtual	bool						isSubframeworkOf(const LinkContext& context, const ImageLoader* image) const = 0;
	virtual	bool						hasSubLibrary(const LinkContext& context, const ImageLoader* child) const = 0;
	virtual uint32_t*					segmentCommandOffsets() const = 0;
	virtual	void						rebase(const LinkContext& context) = 0;
	virtual const ImageLoader::Symbol*	findExportedSymbol(const char* name, const ImageLoader** foundIn) const = 0;
	virtual bool						containsSymbol(const void* addr) const = 0;
	virtual uintptr_t					exportedSymbolAddress(const LinkContext& context, const Symbol* symbol, bool runResolver) const = 0;
	virtual bool						exportedSymbolIsWeakDefintion(const Symbol* symbol) const = 0;
	virtual const char*					exportedSymbolName(const Symbol* symbol) const = 0;
	virtual unsigned int				exportedSymbolCount() const = 0;
	virtual const ImageLoader::Symbol*	exportedSymbolIndexed(unsigned int) const = 0;
	virtual unsigned int				importedSymbolCount() const = 0;
	virtual const ImageLoader::Symbol*	importedSymbolIndexed(unsigned int) const = 0;
	virtual const char*					importedSymbolName(const Symbol* symbol) const = 0;
#if PREBOUND_IMAGE_SUPPORT
	virtual void						resetPreboundLazyPointers(const LinkContext& context) = 0;
#endif
	

	virtual void		doGetDependentLibraries(DependentLibraryInfo libs[]);
	virtual LibraryInfo doGetLibraryInfo();
	virtual	void		getRPaths(const LinkContext& context, std::vector<const char*>&) const;
	virtual	bool		getUUID(uuid_t) const;
	virtual void		doRebase(const LinkContext& context);
	virtual void		doBind(const LinkContext& context, bool forceLazysBound) = 0;
	virtual void		doBindJustLazies(const LinkContext& context) = 0;
	virtual bool		doInitialization(const LinkContext& context);
	virtual void		doGetDOFSections(const LinkContext& context, std::vector<ImageLoader::DOFInfo>& dofs);
	virtual bool		needsTermination();
	virtual bool		segmentsMustSlideTogether() const;	
	virtual bool		segmentsCanSlide() const;			
	virtual void		setSlide(intptr_t slide);		
	virtual bool		usesTwoLevelNameSpace() const;
	virtual bool		isPrebindable() const;

		
protected:

			void		destroy();
	static void			sniffLoadCommands(const macho_header* mh, const char* path, bool* compressed,
											unsigned int* segCount, unsigned int* libCount,
											const linkedit_data_command** codeSigCmd);
	static bool			needsAddedLibSystemDepency(unsigned int libCount, const macho_header* mh);
#if CODESIGNING_SUPPORT
			void		loadCodeSignature(const struct linkedit_data_command* codeSigCmd, int fd, uint64_t offsetInFatFile);
#endif
			const struct macho_segment_command* segLoadCommand(unsigned int segIndex) const;
			void		parseLoadCmds();
			bool		segHasRebaseFixUps(unsigned int) const;
			bool		segHasBindFixUps(unsigned int) const;
			void		segProtect(unsigned int segIndex, const ImageLoader::LinkContext& context);
			void		segMakeWritable(unsigned int segIndex, const ImageLoader::LinkContext& context);
#if __i386__
			bool		segIsReadOnlyImport(unsigned int) const;
#endif
			intptr_t	assignSegmentAddresses(const LinkContext& context);
			uintptr_t	reserveAnAddressRange(size_t length, const ImageLoader::LinkContext& context);
			bool		reserveAddressRange(uintptr_t start, size_t length);
			void		mapSegments(int fd, uint64_t offsetInFat, uint64_t lenInFat, uint64_t fileLen, const LinkContext& context);
			void		mapSegments(const void* memoryImage, uint64_t imageLen, const LinkContext& context);
			void		UnmapSegments();
			void		__attribute__((noreturn)) throwSymbolNotFound(const LinkContext& context, const char* symbol, 
																	const char* referencedFrom, const char* expectedIn);
			void		doImageInit(const LinkContext& context);
			void		doModInitFunctions(const LinkContext& context);
			void		setupLazyPointerHandler(const LinkContext& context);
			void		lookupProgramVars(const LinkContext& context) const;
			uintptr_t	bindLocation(const LinkContext& context, uintptr_t location, uintptr_t value, 
										const ImageLoader* targetImage, uint8_t type, const char* symbolName, 
										intptr_t addend, const char* msg);
			
			void		makeTextSegmentWritable(const LinkContext& context, bool writeable);
			void		preFetchDATA(int fd, uint64_t offsetInFat, const LinkContext& context);


			void		doInterpose(const LinkContext& context) = 0;
			bool		hasReferencesToWeakSymbols() const;
			uintptr_t	getSymbolAddress(const Symbol* sym, const ImageLoader* requestor, 
										const LinkContext& context, bool runResolver) const;
			
	static uintptr_t			bindLazySymbol(const mach_header*, uintptr_t* lazyPointer);
protected:			
	const uint8_t*							fMachOData;
	const uint8_t*							fLinkEditBase; // add any internal "offset" to this to get mapped address
	uintptr_t								fSlide;
	uint32_t								fEHFrameSectionOffset;
	uint32_t								fUnwindInfoSectionOffset;
	uint32_t								fDylibIDOffset;
	uint32_t								fSegmentsCount : 8,
											fIsSplitSeg : 1,
											fInSharedCache : 1,
#if TEXT_RELOC_SUPPORT
											fTextSegmentRebases : 1, 
											fTextSegmentBinds : 1, 
#endif
#if __i386__
											fReadOnlyImportSegment : 1,
#endif
											fHasSubLibraries : 1,
											fHasSubUmbrella : 1,
											fInUmbrella : 1,
											fHasDOFSections : 1,
											fHasDashInit : 1,
											fHasInitializers : 1,
											fHasTerminators : 1,
											fGoodFirstSegment : 1,
											fRegisteredAsRequiresCoalescing : 1; 	// <rdar://problem/7886402> Loading MH_DYLIB_STUB causing coalescable miscount
											
											
	static uint32_t					fgSymbolTableBinarySearchs;
	static uint32_t					fgSymbolTrieSearchs;
};


#endif // __IMAGELOADERMACHO__