io Programmo 10/ioProg_10.iso/soft/optima/samples.z/ReadExe.cpp

C/C++ Source or Header | 1996-03-22 | 5.6 KB | 185 lines

#include "wpch.hpp"

typedef unsigned char unsigned_8;
typedef unsigned short unsigned_16;
typedef unsigned long unsigned_32;
#include <unistd.h>
#include <stdio.h>
#include <fcntl.h>
#include <malloc.h>
#include <stddef.h>

#pragma pack(push,1);

/* DOS EXE file header */
/* =================== */

typedef struct dos_exe_header {
    unsigned_16         signature;      /* signature to mark valid EXE file */
    unsigned_16         mod_size;       /* length of image mod 512          */
    unsigned_16         file_size;      /* number of 512 byte pages         */
    unsigned_16         num_relocs;     /* number of relocation items       */
    unsigned_16         hdr_size;       /* size of header (in paragraphs)   */
    unsigned_16         min_16;         /* minimum # of paragraphs          */
    unsigned_16         max_16;         /* maximum # of paragraphs          */
    unsigned_16         SS_offset;      /* offset of SS within load module  */
    unsigned_16         SP;             /* value for SP                     */
    unsigned_16         chk_sum;        /* check sum                        */
    unsigned_16         IP;             /* value for IP                     */
    unsigned_16         CS_offset;      /* offset of CS within load module  */
    unsigned_16         reloc_offset;   /* offset to 1st relocation item    */
    unsigned_16         overlay_num;    /* overlay number (0 if resident)   */
} dos_exe_header;


/* PE executable format structures */

/* type of a [relative] virtual address */
typedef    unsigned_32    pe_va;

/* PE header table types */
enum {
    PE_TBL_EXPORT,
    PE_TBL_IMPORT,
    PE_TBL_RESOURCE,
    PE_TBL_EXCEPTION,
    PE_TBL_SECURITY,
    PE_TBL_FIXUP,
    PE_TBL_DEBUG,
    PE_TBL_DESCRIPTION,
    PE_TBL_MACHINE,
    PE_TBL_THREAD,
    PE_TBL_CALLBACKS,
    PE_TBL_NUMBER = 16
};

#define OLD_PE_TBL_NUMBER 9

typedef struct {
        pe_va        rva;
    unsigned_32    size;
} pe_hdr_table_entry;

/* PE header structure */
typedef struct {
    unsigned_32        signature;
    unsigned_16        cpu_type;
    unsigned_16        num_objects;
    unsigned_32        time_stamp;
    unsigned_32        sym_table;
    unsigned_32        num_syms;
    unsigned_16        nt_hdr_size;    /* # of bytes after the flags field */
    unsigned_16        flags;
    unsigned_16        magic;        /* currently 0x10b */
    unsigned_8        lnk_major;
    unsigned_8        lnk_minor;
    unsigned_32        code_size;
    unsigned_32        init_data_size;
    unsigned_32        uninit_data_size;
    pe_va        entry_rva;
    unsigned_32        code_base;
    unsigned_32        data_base;
    unsigned_32        image_base;
    unsigned_32        object_align;
    unsigned_32        file_align;
    unsigned_16        os_major;
    unsigned_16        os_minor;
    unsigned_16        user_major;
    unsigned_16        user_minor;
    unsigned_16        subsys_major;
    unsigned_16        subsys_minor;
    unsigned_32        rsvd1;
    unsigned_32        image_size;
    unsigned_32        header_size;  //size of dos hdr, nt hdr, obj table & pad
    unsigned_32        file_checksum;
    unsigned_16        subsystem;
    unsigned_16        dll_flags;
    unsigned_32        stack_reserve_size;
    unsigned_32        stack_commit_size;
    unsigned_32        heap_reserve_size;
    unsigned_32        heap_commit_size;
    unsigned_32        tls_idx_addr;
    unsigned_32        num_tables;
    pe_hdr_table_entry    table[PE_TBL_NUMBER];
} pe_header;


/* PE object table structure */
#define PE_OBJ_NAME_LEN 8
typedef struct {
    unsigned_8        name[PE_OBJ_NAME_LEN];
    unsigned_32        virtual_size;
    pe_va        rva;
    unsigned_32        physical_size;
    unsigned_32        physical_offset;
    unsigned_32        relocs_rva;
    unsigned_32        linnum_rva;
    unsigned_16        num_relocs;
    unsigned_16        num_linnums;
    unsigned_32        flags;
} pe_object;

#pragma pack(pop);

int Handle;

#define DOS_SIGNATURE     0x5a4d
#define OS2_EXE_HEADER_FOLLOWS    0x0040    /* reloc table offset 0x40 */
#define NH_OFFSET    0x003c
/*
 * Dump the Object Table.
 */

bool FindObject( WString const &exe, WString &object, DWORD start, DWORD size )
{
    unsigned_32        new_exe_off;    /* offset of new exe head  */
    pe_header        pe_head;    /* the pe_header        */
    unsigned_16        i;
    pe_object        *pe_obj;
    struct dos_exe_header    dos_head;
    char            name[PE_OBJ_NAME_LEN+1];

    class TheFile {
    public:
        TheFile( const char *name ) {
        handle = open( name, O_RDONLY | O_BINARY, 0 );
        }
        ~TheFile()
        {
        if( handle != -1 ) close( handle );
        }
        int handle;
    };

    TheFile file( exe );
    if( file.handle == -1 ) return( false );
    read( file.handle, &dos_head, sizeof( dos_head ) );
    if( dos_head.signature != DOS_SIGNATURE ) {
        return( false );
    }
    if( dos_head.reloc_offset != OS2_EXE_HEADER_FOLLOWS ) {
        return( false );
    }
    lseek( file.handle, NH_OFFSET, SEEK_SET );
    read( file.handle, &new_exe_off, sizeof( new_exe_off ) );
    lseek( file.handle, new_exe_off, SEEK_SET );
    read( file.handle, &pe_head, sizeof( pe_header ) );
    lseek( file.handle, new_exe_off + offsetof( pe_header, magic ) + pe_head.nt_hdr_size, SEEK_SET );

    if( pe_head.num_objects == 0 ) return( false );
    pe_obj = (pe_object*)malloc( pe_head.num_objects * sizeof(pe_object) );
    read( file.handle, pe_obj, pe_head.num_objects * sizeof(pe_object) );
    for( i = 0; i < pe_head.num_objects; i++ ) {
        if( pe_obj[i].rva >= start && pe_obj[i].rva < start+size ) {
            object += " ";
            memset( name, 0, sizeof( name ) );
            memcpy( name, pe_obj[i].name, sizeof( pe_obj[i].name ) );
            object += name;
        }

    }
    free( pe_obj );
    return( true );
}