Cxbx-Reloaded/Source/Win32/CxbxKrnl/EmuX.cpp

// ******************************************************************
// *
// *    .,-:::::    .,::      .::::::::.    .,::      .:
// *  ,;;;'````'    `;;;,  .,;;  ;;;'';;'   `;;;,  .,;; 
// *  [[[             '[[,,[['   [[[__[[\.    '[[,,[['  
// *  $$$              Y$$$P     $$""""Y$$     Y$$$P    
// *  `88bo,__,o,    oP"``"Yo,  _88o,,od8P   oP"``"Yo,  
// *    "YUMMMMMP",m"       "Mm,""YUMMMP" ,m"       "Mm,
// *
// *   Cxbx->Win32->CxbxKrnl->EmuX.cpp
// *
// *  This file is part of the Cxbx project.
// *
// *  Cxbx and Cxbe 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 recieved 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, Bostom, MA 02111-1307, USA.
// *
// *  (c) 2002-2003 Aaron Robinson <caustik@caustik.com>
// *
// *  All rights reserved
// *
// ******************************************************************
#define CXBXKRNL_INTERNAL
#define _XBOXKRNL_LOCAL_

#include "Cxbx.h"
#include "EmuX.h"

// ******************************************************************
// * ntdll wrapped in namespace to avoid collisions
// ******************************************************************
namespace xntdll
{
    #include "xntdll.h"
};

#include <windows.h>
#include <stdio.h>

// ******************************************************************
// * static functions
// ******************************************************************
static void EmuXInstallWrappers(void (*Entry)());

// ******************************************************************
// * func: EmuXInit
// ******************************************************************
CXBXKRNL_API void NTAPI EmuXInit(DebugMode DebugConsole, char *DebugFilename, uint08 *XBEHeader, uint32 XBEHeaderSize, void (*Entry)())
{
    // ******************************************************************
    // * debug console allocation (if configured)
    // ******************************************************************
    if(DebugConsole == DM_CONSOLE)
    {
        if(AllocConsole())
        {
            freopen("CONOUT$", "wt", stdout);

            printf("CxbxKrnl [0x%.08X]: Debug console allocated.\n", GetCurrentThreadId());
        }
    }
    else if(DebugConsole == DM_FILE)
    {
        FreeConsole();

        freopen(DebugFilename, "wt", stdout);

        printf("EmuX (0x%.08X): Debug console allocated.\n", GetCurrentThreadId());
    }

    // ******************************************************************
    // * debug trace
    // ******************************************************************
    {
        printf("EmuX: EmuXInit\n"
               "(\n"
               "   DebugConsole        : 0x%.08X\n"
               "   DebugFilename       : \"%s\"\n"
               "   XBEHeader           : 0x%.08X\n"
               "   XBEHeaderSize       : 0x%.08X\n"
               "   Entry               : 0x%.08X\n"
               ");\n",
               DebugConsole, DebugFilename, XBEHeader, XBEHeaderSize, Entry);
    }

    // ******************************************************************
    // * Locate functions and install wrapper vectors
    // ******************************************************************
    {
        EmuXInstallWrappers(Entry);
    }

    // ******************************************************************
    // * Load the necessary pieces of XBEHeader
    // ******************************************************************
    {
        uint32 old_protection = 0;

        VirtualProtect((void*)0x00010000, 0x1000, PAGE_READWRITE, &old_protection);

        // we sure hope we aren't corrupting anything necessary for an .exe to survive :]
        uint32 dwSizeofHeaders   = *(uint32*)&XBEHeader[0x0108];
        uint32 dwCertificateAddr = *(uint32*)&XBEHeader[0x0118];
        uint32 dwInitFlags       = *(uint32*)&XBEHeader[0x0124];
        uint32 dwPeHeapReserve   = *(uint32*)&XBEHeader[0x0134];
        uint32 dwPeHeapCommit    = *(uint32*)&XBEHeader[0x0138];

        *(uint32 *)0x00010108 = dwSizeofHeaders;
        *(uint32 *)0x00010118 = dwCertificateAddr;
        *(uint32 *)0x00010124 = dwInitFlags;
        *(uint32 *)0x00010134 = dwPeHeapReserve;
        *(uint32 *)0x00010138 = dwPeHeapCommit;

        memcpy((void*)dwCertificateAddr, &XBEHeader[dwCertificateAddr - 0x00010000], sizeof(Xbe::Certificate));
    }

    // ******************************************************************
    // * Initialize FS system
    // ******************************************************************
    {
        EmuXInitFS();
    }

    // ******************************************************************
    // * Initialize FS:* structure
    // ******************************************************************
    {
        EmuXGenerateFS();
    }

    printf("EmuX (0x%.08X): Initial thread starting.\n", GetCurrentThreadId());

    // This must be enabled or the debugger may crash (sigh)
    // __asm _emit 0xF1

    EmuXSwapFS();   // XBox FS

    Entry();

    EmuXSwapFS();   // Win2k/XP FS

    printf("EmuX (0x%.08X): Initial thread ended.\n", GetCurrentThreadId());

    fflush(stdout);

    return;
}

// ******************************************************************
// * func: EmuXDummy
// ******************************************************************
CXBXKRNL_API void NTAPI EmuXDummy()
{
    EmuXSwapFS();   // Win2k/XP FS

    printf("EmuX (0x%.08X): EmuXDummy()\n", GetCurrentThreadId());

    EmuXSwapFS();   // XBox FS
}

// ******************************************************************
// * func: EmuXPanic
// ******************************************************************
CXBXKRNL_API void NTAPI EmuXPanic()
{
    EmuXSwapFS();   // Win2k/XP FS

    printf("EmuX (0x%.08X): EmuXPanic()\n", GetCurrentThreadId());

    MessageBox(NULL, "Kernel Panic! Process will now terminate.", "CxbxKrnl", MB_OK | MB_ICONEXCLAMATION);

    EmuXSwapFS();   // XBox FS
}

// ******************************************************************
// * func: EmuXFindFuncByIndirectCall
// ******************************************************************
inline void *EmuXFindFuncByIndirectCall(void *Function, uint32 CallOffset)
{
    uint32 RelCallAddr = (uint32)Function + CallOffset;

    uint32 RelFunc = *(uint32*)(RelCallAddr + 1);

    void  *Func = (void*)(RelCallAddr + RelFunc + 5);

    return Func;
}

// ******************************************************************
// * func: EmuXFindFuncByPush32
// ******************************************************************
inline void *EmuXFindFuncByPush32(void *Function, uint32 PushOffset)
{
    uint32 AbsPushAddr = (uint32)Function + PushOffset;

    uint32 AbsFunc = *(uint32*)(AbsPushAddr + 1);

    void  *Func = (void*)(AbsFunc);

    return Func;
}

// ******************************************************************
// * func: EmuXInstallWrapper
// ******************************************************************
inline void EmuXInstallWrapper(void *FunctionAddr, void *WrapperAddr)
{
    uint08 *FuncBytes = (uint08*)FunctionAddr;

    *(uint08*)&FuncBytes[0] = 0xE9;
    *(uint32*)&FuncBytes[1] = (uint32)WrapperAddr - (uint32)FunctionAddr - 5;
}

// ******************************************************************
// * func: EmuXInstallWrappers
// ******************************************************************
void EmuXInstallWrappers(void (*Entry)())
{
    // ******************************************************************
    // * debug trace
    // ******************************************************************
    {
        printf("EmuX: EmuXInstallWrappers\n"
               "(\n"
               "   Entry               : 0x%.08X\n"
               ");\n",
            Entry);
    }

    // ******************************************************************
    // * locate and patch functions
    // ******************************************************************
    {
        void *RealmainXapiStartup = EmuXFindFuncByPush32(Entry, 0x4B);

        printf("EmuXInstallWrappers: mainXapiStartup -> 0x%.08X\n", RealmainXapiStartup);

        // ******************************************************************
        // * install CreateThread vector
        // ******************************************************************
        {
            void *RealCreateThread = EmuXFindFuncByIndirectCall(Entry, 0x54);

            printf("EmuXInstallWrappers: CreateThread    -> 0x%.08X\n", RealCreateThread);

            EmuXInstallWrapper(RealCreateThread, xboxkrnl::EmuXCreateThread);
        }

        // ******************************************************************
        // * install CloseHandle vector
        // ******************************************************************
        {
            void *RealCloseHandle = EmuXFindFuncByIndirectCall(Entry, 0x6A);

            printf("EmuXInstallWrappers: CloseHandle     -> 0x%.08X\n", RealCloseHandle);

            EmuXInstallWrapper(RealCloseHandle, xboxkrnl::EmuXCloseHandle);
        }

        // ******************************************************************
        // * XapiInitProcess
        // ******************************************************************
        {
            void *RealXapiInitProcess = EmuXFindFuncByIndirectCall(RealmainXapiStartup, 0x00);

            printf("EmuXInstallWrappers: XapiInitProcess -> 0x%.08X\n", RealXapiInitProcess);

            EmuXInstallWrapper(RealXapiInitProcess, xboxkrnl::EmuXapiInitProcess);
        }

        // ******************************************************************
        // * XapiBootDash
        // ******************************************************************
        {
            void *RealXapiBootDash = EmuXFindFuncByIndirectCall(RealmainXapiStartup, 0x65);

            printf("EmuXInstallWrappers: XapiBootDash -> 0x%.08X\n", RealXapiBootDash);

            EmuXInstallWrapper(RealXapiBootDash, xboxkrnl::EmuXapiBootDash);
        }

        // ******************************************************************
        // * __rcinit
        // ******************************************************************
        {
            void *Real__rcinit = EmuXFindFuncByIndirectCall(RealmainXapiStartup, 0x47);

            printf("EmuXInstallWrappers: __rcinit -> 0x%.08X\n", Real__rcinit);

            EmuXInstallWrapper(Real__rcinit, xboxkrnl::EmuX__rcinit);
        }

        // ******************************************************************
        // * __cinit
        // ******************************************************************
        {
            void *Real__cinit = EmuXFindFuncByIndirectCall(RealmainXapiStartup, 0x4C);

            printf("EmuXInstallWrappers: __cinit -> 0x%.08X\n", Real__cinit);

            EmuXInstallWrapper(Real__cinit, xboxkrnl::EmuX__cinit);
        }
    }
}