hasherezade-bearparser/parser/include/bearparser/pe/DOSExe.h

#pragma once

#include "../MappedExe.h"
#include "DosHdrWrapper.h"

#define DOS_PARAGRAPH 0x10

class DOSExeBuilder: public ExeBuilder {
public:
    DOSExeBuilder() : ExeBuilder() {}
    virtual bool signatureMatches(AbstractByteBuffer *buf);
    virtual Executable* build(AbstractByteBuffer *buf);
    QString typeName() { return "MZ"; }
};

//-------------------------------------------------------------

class DOSExe : public MappedExe
{
public:
    enum WRAPPERS {
        WR_NONE = MappedExe::WR_NONE,
        WR_DOS_HDR = 0,
        COUNT_WRAPPERS
    };

    DOSExe(AbstractByteBuffer *v_buf);
    virtual ~DOSExe() { }

    virtual exe_arch getArch() { return exe_arch::ARCH_INTEL; }
    
    // inherited from Executable:
    //
    virtual void wrap();
    // FileAddr <-> RVA
    virtual offset_t rawToRva(offset_t raw) { return (raw < codeOffset()) ? INVALID_ADDR : raw - codeOffset(); }
    virtual offset_t rvaToRaw(offset_t rva) { return rva + codeOffset();  } //TODO

    virtual bufsize_t getMappedSize(Executable::addr_type aType)
    {
        if (aType == Executable::RAW)
            return getContentSize();
        return moduleSize() - codeOffset();
    }

    virtual bufsize_t getAlignment(Executable::addr_type aType) const { return 0; } //TODO
    virtual offset_t getImageBase(bool recalculate = false) { return m_dosHdr->e_cs; }
    virtual offset_t getEntryPoint(Executable::addr_type aType = Executable::RVA) { return codeOffset() + m_dosHdr->e_ip; }

    //---
    // DOS Exe only:
    virtual offset_t dosHeaderOffset() { return 0; } //wrapper's mount point
    offset_t peSignatureOffset();

protected:
    offset_t codeOffset() { return static_cast<offset_t> (m_dosHdr->e_cparhdr) * DOS_PARAGRAPH; }
    bufsize_t moduleSize()
    {
        const size_t unit_size = 0x200;
        WORD size = m_dosHdr->e_cp * unit_size;
        if (m_dosHdr->e_cblp ) {
            WORD trimSize = unit_size - m_dosHdr->e_cblp;
            size -= trimSize;
        }
        return static_cast<bufsize_t> (size);
    }


    DosHdrWrapper *dosHdrWrapper;
    IMAGE_DOS_HEADER* m_dosHdr;
};