/* linker.h -- This file is part of the UPX executable compressor. Copyright (C) 1996-2006 Markus Franz Xaver Johannes Oberhumer Copyright (C) 1996-2006 Laszlo Molnar All Rights Reserved. UPX and the UCL library are free software; you can redistribute them and/or modify them under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; see the file COPYING. If not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. Markus F.X.J. Oberhumer Laszlo Molnar markus@oberhumer.com ml1050@users.sourceforge.net */ #ifndef __UPX_LINKER_H #define __UPX_LINKER_H /************************************************************************* // **************************************************************************/ class Linker { protected: Linker() : frozen(false) { } public: virtual ~Linker() { } // endian abstraction virtual unsigned get32(const void *b) const = 0; virtual void set32(void *b, unsigned v) const = 0; // virtual bool isFrozen() const { return frozen; } // virtual void init(const void *pdata, int plen, int pinfo) = 0; virtual void setLoaderAlignOffset(int phase) = 0; virtual int addSection(const char *sname) = 0; virtual void addSection(const char *sname, const void *sdata, int slen, int align) = 0; virtual void freeze() = 0; virtual int getSection(const char *sname, int *slen=NULL) = 0; virtual unsigned char *getLoader(int *llen=NULL) = 0; // for ElfLinker descendants virtual void defineSymbol(const char *, unsigned) {} virtual void relocate() {} virtual unsigned getSymbolOffset(const char *) const { return 0; } protected: bool frozen; private: // disable copy and assignment Linker(const Linker &); // {} Linker& operator= (const Linker &); // { return *this; } }; /************************************************************************* // DefaultLinker **************************************************************************/ class DefaultLinker : public Linker { protected: DefaultLinker(); public: virtual ~DefaultLinker(); // virtual void init(const void *pdata, int plen, int pinfo); virtual void setLoaderAlignOffset(int phase); virtual int addSection(const char *sname); virtual void addSection(const char *sname, const void *sdata, int slen, int align); virtual void freeze(); virtual int getSection(const char *sname, int *slen=NULL); virtual unsigned char *getLoader(int *llen=NULL); private: struct Label; struct Jump; struct Section; unsigned char *iloader, *oloader; int ilen, olen; int info; Jump *jumps; int njumps; Section *sections; int nsections; int align_hack; int align_offset; }; template struct TDefaultLinker : public DefaultLinker { virtual unsigned get32(const void *b) const { return T::get32(b); } virtual void set32(void *b, unsigned v) const { T::set32(b, v); } }; typedef TDefaultLinker DefaultBELinker; typedef TDefaultLinker DefaultLELinker; /************************************************************************* // SimpleLinker **************************************************************************/ class SimpleLinker : public Linker { protected: SimpleLinker(); public: virtual ~SimpleLinker(); // virtual void init(const void *pdata, int plen, int pinfo); virtual void setLoaderAlignOffset(int phase); virtual int addSection(const char *sname); virtual void addSection(const char *sname, const void *sdata, int slen, int align); virtual void freeze(); virtual int getSection(const char *sname, int *slen=NULL); virtual unsigned char *getLoader(int *llen=NULL); private: unsigned char *oloader; int olen; }; template struct TSimpleLinker : public SimpleLinker { virtual unsigned get32(const void *b) const { return T::get32(b); } virtual void set32(void *b, unsigned v) const { T::set32(b, v); } }; typedef TSimpleLinker SimpleBELinker; typedef TSimpleLinker SimpleLELinker; /************************************************************************* // ElfLinker **************************************************************************/ class ElfLinker : public Linker, private nocopy { typedef Linker super; protected: struct Section; struct Symbol; struct Relocation; upx_byte *input; int inputlen; upx_byte *output; int outputlen; Section *head; Section *tail; Section **sections; Symbol **symbols; Relocation **relocations; unsigned nsections; unsigned nsymbols; unsigned nrelocations; void preprocessSections(char *start, const char *end); void preprocessSymbols(char *start, const char *end); void preprocessRelocations(char *start, const char *end); Section *findSection(const char *name); Symbol *findSymbol(const char *name); void addSymbol(const char *name, const char *section, unsigned offset); void addRelocation(const char *section, unsigned off, const char *type, const char *symbol, unsigned add); public: ElfLinker(); protected: virtual ~ElfLinker(); virtual void init(const void *pdata, int plen, int); virtual void setLoaderAlignOffset(int phase); virtual int addSection(const char *sname); virtual void addSection(const char *sname, const void *sdata, int slen, int align); virtual void freeze(); virtual int getSection(const char *sname, int *slen=NULL); virtual upx_byte *getLoader(int *llen=NULL); virtual void relocate(); virtual void defineSymbol(const char *name, unsigned value); virtual unsigned getSymbolOffset(const char *) const; virtual unsigned get32(const void *) const { return 0; } virtual void set32(void *, unsigned) const {} // void alignWithByte(unsigned len, upx_byte b); virtual void align(unsigned len); virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; struct ElfLinker::Section : private nocopy { char *name; void *input; upx_byte *output; unsigned size; unsigned offset; unsigned char align; // log2 Section *next; Section(const char *n, const void *i, unsigned s, unsigned a=0); ~Section(); }; struct ElfLinker::Symbol : private nocopy { char *name; Section *section; unsigned offset; Symbol(const char *n, Section *s, unsigned o); ~Symbol(); }; struct ElfLinker::Relocation : private nocopy { Section *section; unsigned offset; const char *type; Symbol *value; unsigned add; // used in .rela relocations Relocation(Section *s, unsigned o, const char *t, Symbol *v, unsigned a); }; class ElfLinkerX86 : public ElfLinker { typedef ElfLinker super; protected: virtual void align(unsigned len); virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; class ElfLinkerAMD64 : public ElfLinker { typedef ElfLinker super; protected: virtual void align(unsigned len); virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; class ElfLinkerPpc32 : public ElfLinker { typedef ElfLinker super; protected: virtual void align(unsigned len); virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; class ElfLinkerArmLE : public ElfLinker { typedef ElfLinker super; protected: virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; class ElfLinkerArmBE : public ElfLinker { typedef ElfLinker super; protected: virtual void relocate1(Relocation *, upx_byte *location, unsigned value, const char *type); }; #endif /* already included */ /* vi:ts=4:et */