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GeckoLoader/loader.cpp
2020-10-04 02:30:11 -05:00

423 lines
No EOL
11 KiB
C++

//#include <vector>
//#include <string>
//using std::array;
//using std::memcpy;
//using std::memcmp;
//using std::memset;
//using std::string;
#define dcbst(_val) asm volatile("dcbst 0, %0" \
: \
: "r"(_val))
#define dcbf(_val) asm volatile("dcbf 0, %0" \
: \
: "r"(_val))
#define icbi(_val) asm volatile("icbi 0, %0" \
: \
: "r"(_val))
#define call(addr) ((void (*)(...))addr)
#define CODEHANDLER 0x800018A8
#define GCT_MAGIC 0x00D0C0DE
#define __start call(0x4948494C)
using u32 = unsigned int;
using u16 = unsigned short;
using u8 = unsigned char;
using s32 = int;
using s16 = short;
using s8 = char;
using f32 = float;
using f64 = double;
__attribute__((noreturn)) int main();
struct CodeList
{
u16 mBaseASM;
u16 mUpperBase;
u16 mOffsetASM;
u16 mLowerOffset;
};
struct Info
{
const u32 allocsize;
const u32 loaderSize;
const u32 handlerSize;
const u32 codeSize;
const u32 *codehandlerHook;
const u32 crypted;
};
class DiscHeader
{
public:
enum class TVMODE
{
NTSC,
PAL,
DEBUG,
DEBUGPAL,
MPAL,
PAL60
};
struct MetaData
{
const u8 mDiscID; //0x0000
const u16 mGameCode; //0x0001
const u8 mRegionCode; //0x0003
const u16 mMakerCode; //0x0004
const u8 mDiscNumber; //0x0006
const u8 mDiscVersion; //0x0007
const u8 mAudioStreaming; //0x0008
const u8 mStreamBufferSize; //0x0009
const u8 _00[12]; //0x000A
const u32 mWiiMagic; //0x0018
const u32 mGCNMagic; //0x001C
const u32 mNinBootCode; //0x0020
const u32 mAppVersion; //0x0024
const u32 mPhysicalRAMSize; //0x0028
const u32 mBoardModel; //0x002C
u8 *mOSArenaLo; //0x0030
u8 *mOSArenaHi; //0x0034
u32 *mFstStart; //0x0038
u32 mFstSize; //0x003C
u32 mDebuggerPresent; //0x0040
const u32 mDebuggerExceptionMask; //0x0044
void *mExceptionHookDest; //0x0048
const u32 mExceptionReturn; //0x004C
u32 _01[0x10 / 4]; //0x0050
u32 mDebuggerHook[0x24 / 4]; //0x0060
u32 _02[0x3C / 4]; //0x0084
u32 mCurrentOSContext; //0x00C0
u32 mPreviousOSMask; //0x00C4
u32 mCurrentOSMask; //0x00C8
DiscHeader::TVMODE mTVMode; //0x00CC
u32 mARAMSize; //0x00D0
void *mCurOSContextLogical; //0x00D4
void *mDefaultOSThreadLogical; //0x00D8
u32 *mThreadQueueHead; //0x00DC
u32 *mThreadQueueTail; //0x00E0
u32 *mCurrentOSThread; //0x00E4
u32 mDebuggerSize; //0x00E8
u32 *mDebuggerMonitorLoc; //0x00EC
u32 mSimulatedMemSize; //0x00F0
u8 *mBi2HeaderLoc; //0x00F4
u32 mBusClockSpeed; //0x00F8
u32 mCPUClockSpeed; //0x00FC
u32 _04[0x3010 / 4]; //0x0100
u8 *mWiiHeap; //0x3110
};
static MetaData sMetaData;
enum class CONSOLETYPE
{
Gamecube,
Wii,
Unknown
};
inline u32 getGameID() { return ((u32)sMetaData.mDiscID << 24) | ((u32)sMetaData.mGameCode << 8) | ((u32)sMetaData.mRegionCode); }
inline u16 getMakerID() { return sMetaData.mMakerCode; }
inline u8 getDiscNumber() { return sMetaData.mDiscNumber; }
inline u8 getDiscVersion() { return sMetaData.mDiscVersion; }
CONSOLETYPE detectHomeConsole()
{
if (sMetaData.mGCNMagic)
{
return CONSOLETYPE::Gamecube;
}
else if (sMetaData.mWiiMagic)
{
return CONSOLETYPE::Wii;
}
return CONSOLETYPE::Unknown;
}
inline void setHeap(u32 alloc)
{
if (sMetaData.mBi2HeaderLoc < sMetaData.mOSArenaHi)
{
sMetaData.mOSArenaHi = sMetaData.mBi2HeaderLoc - alloc;
if (this->detectHomeConsole() == DiscHeader::CONSOLETYPE::Wii)
{
sMetaData.mWiiHeap = sMetaData.mBi2HeaderLoc - alloc;
}
}
else
{
if (this->detectHomeConsole() == DiscHeader::CONSOLETYPE::Wii)
{
sMetaData.mOSArenaHi = sMetaData.mWiiHeap - alloc;
sMetaData.mWiiHeap -= alloc;
}
else
{
sMetaData.mOSArenaHi -= alloc;
}
}
}
};
static DiscHeader sDisc;
Info gpModInfo = {
0x48454150,
0x4C53495A,
0x4853495A,
0x4353495A,
(const u32 *)0x484F4F4B,
0x43525054,
};
inline u32 extractBranchAddr(u32 *bAddr)
{
s32 offset;
if (*bAddr & 0x2000000)
offset = (*bAddr & 0x3FFFFFD) - 0x4000000;
else
offset = *bAddr & 0x3FFFFFD;
return (u32)bAddr + offset;
}
namespace Memory
{
static void memcpy(u8 *to, u8 *from, s32 size)
{
for (s32 i = 0; i < size; ++i)
{
*to++ = *from++;
}
}
namespace Cache
{
static inline void flushAddr(void *addr)
{
dcbf(addr);
icbi(addr);
}
static void flushRange(u8 *addr, s32 size)
{
size += 31 + (((u32)addr & 31) > 0);
for (u32 i = 0; i < (size >> 5); ++i)
{
flushAddr((void *)(addr + (i << 5)));
}
}
static void storeAddr(void *addr)
{
dcbst(addr);
icbi(addr);
}
static void storeRange(u8 *addr, s32 size)
{
size += 31 + (((u32)addr & 31) > 0);
for (u32 i = 0; i < (size >> 5); ++i)
{
storeAddr((void *)(addr + (i << 5)));
}
}
} // namespace Cache
namespace Direct
{
template <typename T>
static inline void write(T *addr, T value)
{
*addr = value;
Cache::flushAddr(addr);
}
/*This constructs a branch instruction. &TO = ((TO - FROM) & MAX_OFFSET) | BRANCH_TYPE | !!isLink*/
static inline void branch(void *addr, void *to, bool lk)
{
Direct::write<u32>((u32 *)(addr), ((((u32)(to) - (u32)(addr)) & 0x3ffffff) | 0x48000000 | lk));
}
} // namespace Direct
namespace Search
{
static u32 *array(u32 *start, u32 *end, u32 arrayLength, const u32 *hookData)
{
u32 index = 0;
/*Loop through the games RAM, make sure we don't find our own hook data by accident*/
for (u32 i = 0; &start[i] < end; ++i)
{
/*If the data matches, increase the index counter and continue search,
else set index to 0 and continue searching*/
if (start[i] == hookData[index])
++index;
else
index = 0;
/*If the data has matched the whole array, return the address of the match*/
if (index >= (arrayLength) && (&start[i] < (u32 *)&gpModInfo || &start[i] > (u32 *)&gpModInfo + sizeof(Info)))
return &start[i];
}
return nullptr;
}
template <typename T>
static T *single(T *start, T *end, T match)
{
for (u32 i = 0; &start[i] < end; ++i)
{
if (start[i] == match)
{
return &start[i];
}
}
return nullptr;
}
/*Call this after viHook, finds the address of the first instance
of targetVal, and hooks it to the pointer hookTo*/
static inline void hookFunction(u32 *start, u32 targetVal, void *hookTo, bool lk)
{
Direct::branch(Search::single<u32>(start, start + 0x500, targetVal), hookTo, lk);
}
} // namespace Search
class Crypt
{
private:
u32 key;
u32 getKey()
{
u32 b1 = (this->key >> 24) & 0xFF;
u32 b2 = (this->key >> 16) & 0xFF;
u32 b3 = (this->key >> 8) & 0xFF;
u32 b4 = this->key & 0xFF;
b1 ^= b2;
b2 ^= b3;
b3 ^= b4;
return (b4 << 24) | (b3 << 16) | (b2 << 8) | b1;
}
void setKey(u32 key)
{
u32 b1 = key & 0xFF;
u32 b2 = (key >> 8) & 0xFF;
u32 b3 = (key >> 16) & 0xFF;
u32 b4 = (key >> 24) & 0xFF;
b3 ^= b4;
b2 ^= b3;
b1 ^= b2;
this->key = (b1 << 24) | (b2 << 16) | (b3 << 8) | b4;
}
public:
Crypt(u32 key)
{
this->key = key;
}
inline void xorCrypt(u32 *dest, u32 *buffer, u32 size)
{
auto key = this->getKey();
for (u32 i = 0; i < size; ++i)
{
dest[i] = buffer[i] ^ key;
key += i << 3;
}
}
};
enum class Space : u32
{
Start = 0x80000000,
End = 0x81800000,
Size = 0x1800000
};
} // namespace Memory
Memory::Crypt gpCryptor = {0x43595054};
static void initMods()
{
sDisc.setHeap(gpModInfo.allocsize); /*Reallocate the internal heap*/
/*Change codelist pointer to the new address in the allocation*/
CodeList *codelistPointer = (CodeList *)((u32)&gpModInfo + sizeof(Info) + 0xFC);
codelistPointer->mUpperBase = (((u32)sDisc.sMetaData.mOSArenaHi + gpModInfo.handlerSize) >> 16) & 0xFFFF;
codelistPointer->mLowerOffset = ((u32)sDisc.sMetaData.mOSArenaHi + gpModInfo.handlerSize) & 0xFFFF;
/*Copy codelist to the new allocation*/
if (gpModInfo.crypted)
{
Memory::memcpy(sDisc.sMetaData.mOSArenaHi, (u8 *)&gpModInfo + sizeof(Info) + 4, gpModInfo.handlerSize);
gpCryptor.xorCrypt((u32 *)(sDisc.sMetaData.mOSArenaHi + gpModInfo.handlerSize), (u32 *)((u8 *)&gpModInfo + sizeof(Info) + gpModInfo.handlerSize + 4), gpModInfo.codeSize >> 2);
}
else
{
Memory::memcpy(sDisc.sMetaData.mOSArenaHi, (u8 *)&gpModInfo + sizeof(Info) + 4, gpModInfo.handlerSize + gpModInfo.codeSize);
}
/*Get codehandler hook resources*/
auto fillInField = Memory::Search::single<u32>((u32 *)sDisc.sMetaData.mOSArenaHi, (u32 *)(sDisc.sMetaData.mOSArenaHi + 0x600), 0x00DEDEDE);
auto returnAddress = extractBranchAddr((u32 *)gpModInfo.codehandlerHook);
auto ppc = *gpModInfo.codehandlerHook;
/*Write hook branch*/
Memory::Direct::branch((void *)gpModInfo.codehandlerHook, (void *)((u32)sDisc.sMetaData.mOSArenaHi + 0xA8), false); //entryhook
/*Temporary nop*/
*fillInField = 0x60000000;
/*Flush the cache so that the instructions update*/
Memory::Cache::flushRange((u8 *)sDisc.sMetaData.mOSArenaHi, gpModInfo.handlerSize + gpModInfo.codeSize);
/*Call the codehandler*/
call((void *)((u32)(sDisc.sMetaData.mOSArenaHi) + 0xA8))();
/*Write original instruction or translate offset data if a branch*/
if (((ppc >> 24) & 0xFF) > 0x47 && ((ppc >> 24) & 0xFF) < 0x4C)
{
Memory::Direct::branch((void *)fillInField, (void *)returnAddress, ppc & 1);
}
else
{
Memory::Direct::write(fillInField, ppc);
}
/*Write branch back to the hook address + 4*/
Memory::Direct::branch((void *)&fillInField[1], (void *)(&gpModInfo.codehandlerHook[1]), false); //return
}
int main()
{
if (sDisc.detectHomeConsole() != DiscHeader::CONSOLETYPE::Unknown)
{
initMods();
}
__start();
}