/*
* SfExtractDropper
*
* Purpose:
*
* Extract Sirefef/ZeroAccess from image resource.
*
* CNG variant
*
*/
UINT SfExtractDropper(
LPWSTR lpCommandLine
)
{
BOOL cond = FALSE, bSuccess = FALSE;
ULONG c, uKey = 0, imagesz;
WCHAR szInputFile[MAX_PATH + 1];
WCHAR szOutputFile[MAX_PATH + 1];
WCHAR szKey[MAX_PATH];
PVOID ImageBase = NULL, EncryptedData = NULL, DecryptedData = NULL;
IStream *pImageStream = NULL;
ULONG_PTR gdiplusToken = 0;
GdiplusStartupInput input;
GdiplusStartupOutput output;
PVOID BitmapPtr = NULL;
GdiPlusBitmapData BitmapData;
GdiPlusRect rect;
SIZE_T sz;
PULONG ptr, i_ptr;
//input file
c = 0;
RtlSecureZeroMemory(szInputFile, sizeof(szInputFile));
GetCommandLineParam(lpCommandLine, 1, (LPWSTR)&szInputFile, MAX_PATH, &c);
if (c == 0) {
SfcuiPrintText(g_ConOut,
T_SFEXTRACTUSAGE,
g_ConsoleOutput, FALSE);
return (UINT)-1;
}
//output file
c = 0;
RtlSecureZeroMemory(&szOutputFile, sizeof(szOutputFile));
GetCommandLineParam(lpCommandLine, 2, (LPWSTR)&szOutputFile, MAX_PATH, &c);
if (c == 0) {
_strcpy(szOutputFile, TEXT("extracted.bin"));
}
//key
c = 0;
RtlSecureZeroMemory(&szKey, sizeof(szKey));
GetCommandLineParam(lpCommandLine, 3, (LPWSTR)&szKey, MAX_PATH, &c);
if ((c == 0) || (c > 10)) {
SfcuiPrintText(g_ConOut,
T_SFEXTRACTUSAGE,
g_ConsoleOutput, FALSE);
return (UINT)-1;
}
c = 0;
if (locase_w(szKey[1]) == 'x') {
c = 2;
}
uKey = hextoul(&szKey[c]);
do {
ImageBase = SfuCreateFileMappingNoExec(szInputFile);
if (ImageBase == NULL)
break;
c = 0;
EncryptedData = SfLdrQueryResourceData(1, ImageBase, &c);
if ((EncryptedData == NULL) || (c == 0))
break;
pImageStream = SHCreateMemStream((BYTE *)EncryptedData, (UINT)c);
if (pImageStream == NULL)
break;
RtlSecureZeroMemory(&input, sizeof(input));
RtlSecureZeroMemory(&output, sizeof(output));
input.GdiplusVersion = 1;
if (GdiplusStartup(&gdiplusToken, &input, &output) != GdiplusOk)
break;
BitmapPtr = NULL;
if (GdipCreateBitmapFromStream(pImageStream, &BitmapPtr) != GdiplusOk)
break;
RtlSecureZeroMemory(&rect, sizeof(rect));
if (
(GdipGetImageWidth(BitmapPtr, (UINT *)&rect.Width) == GdiplusOk) &&
(GdipGetImageHeight(BitmapPtr, (UINT *)&rect.Height) == GdiplusOk)
)
{
RtlSecureZeroMemory(&BitmapData, sizeof(BitmapData));
if (GdipBitmapLockBits(BitmapPtr, &rect, ImageLockModeRead, PixelFormat32bppARGB, &BitmapData) == GdiplusOk) {
c = (rect.Width * rect.Height);
imagesz = sizeof(ULONG) * c;
sz = imagesz;
DecryptedData = NULL;
NtAllocateVirtualMemory(NtCurrentProcess(), &DecryptedData, 0, &sz, MEM_COMMIT | MEM_RESERVE, PAGE_READWRITE);
if (DecryptedData) {
i_ptr = (PULONG)BitmapData.Scan0;
ptr = DecryptedData;
while (c > 0) {
*ptr = *i_ptr ^ uKey;
ptr++;
i_ptr++;
c--;
}
bSuccess = (SfuWriteBufferToFile(szOutputFile, DecryptedData, imagesz, FALSE, FALSE) == imagesz);
sz = 0;
NtFreeVirtualMemory(NtCurrentProcess(), &DecryptedData, &sz, MEM_RELEASE);
}
GdipBitmapUnlockBits(BitmapPtr, &BitmapData);
}
}
} while (cond);
if (bSuccess == FALSE) {
SfcuiPrintText(g_ConOut,
T_SFEXTRACTFAIL,
g_ConsoleOutput, FALSE);
}
else
{
SfcuiPrintText(g_ConOut,
szOutputFile,
g_ConsoleOutput, TRUE);
SfcuiPrintText(g_ConOut,
T_SFEXTRACTED,
g_ConsoleOutput, TRUE);
}
if (BitmapPtr != NULL) {
GdipDisposeImage(&BitmapPtr);
}
if (gdiplusToken != 0) {
GdiplusShutdown(gdiplusToken);
}
if (pImageStream != NULL) {
pImageStream->lpVtbl->Release(pImageStream);
}
if (ImageBase != NULL) {
NtUnmapViewOfSection(NtCurrentProcess(), ImageBase);
}
return 0;
}
UINT SfDecryptPayload(
LPWSTR lpParameter
)
{
BOOL cond = FALSE, bSuccess = FALSE;
PBYTE cng_object, hashdata, decrypted, enc_data, extracted;
ULONG obj_sz, rlen, hdatasz, enc_data_size;
BCRYPT_ALG_HANDLE h_alg = NULL;
BCRYPT_HASH_HANDLE h_hash = NULL;
BCRYPT_KEY_HANDLE h_rc4key = NULL;
NTSTATUS status;
HANDLE pheap = NULL;
PIMAGE_FILE_HEADER fheader;
PVOID pdll = NULL;
WCHAR InputFile[MAX_PATH + 1], OutputFile[MAX_PATH + 1];
rlen = 0;
RtlSecureZeroMemory(InputFile, sizeof(InputFile));
GetCommandLineParam(lpParameter, 1, InputFile, MAX_PATH, &rlen);
if (rlen == 0) {
SfcuiPrintText(g_ConOut,
T_SFDECRYPTUSAGE,
g_ConsoleOutput, FALSE);
return (UINT)-1;
}
do {
rlen = 0;
GetCommandLineParam(lpParameter, 2, OutputFile, MAX_PATH, &rlen);
if (rlen == 0)
_strcpy(OutputFile, TEXT("out.bin"));
pdll = SfuCreateFileMappingNoExec(InputFile);
if (pdll == NULL)
break;
enc_data_size = 0;
enc_data = SfuQueryResourceData(2, pdll, &enc_data_size);
if (enc_data == NULL)
break;
fheader = &(RtlImageNtHeader(pdll)->FileHeader);
status = BCryptOpenAlgorithmProvider(&h_alg, BCRYPT_MD5_ALGORITHM, NULL, 0);
if (!NT_SUCCESS(status))
break;
obj_sz = 0;
rlen = 0;
status = BCryptGetProperty(h_alg, BCRYPT_OBJECT_LENGTH, (PUCHAR)&obj_sz, sizeof(obj_sz), &rlen, 0);
if (!NT_SUCCESS(status))
break;
hdatasz = 0;
rlen = 0;
status = BCryptGetProperty(h_alg, BCRYPT_HASH_LENGTH, (PUCHAR)&hdatasz, sizeof(hdatasz), &rlen, 0);
if (!NT_SUCCESS(status))
break;
pheap = HeapCreate(0, 0, 0);
if (pheap == NULL)
break;
cng_object = HeapAlloc(pheap, HEAP_ZERO_MEMORY, obj_sz);
if (cng_object == NULL)
break;
hashdata = HeapAlloc(pheap, HEAP_ZERO_MEMORY, hdatasz);
if (hashdata == NULL)
break;
status = BCryptCreateHash(h_alg, &h_hash, cng_object, obj_sz, NULL, 0, 0);
if (!NT_SUCCESS(status))
break;
status = BCryptHashData(h_hash, (PUCHAR)fheader, sizeof(IMAGE_FILE_HEADER), 0);
if (!NT_SUCCESS(status))
break;
status = BCryptFinishHash(h_hash, hashdata, hdatasz, 0);
if (!NT_SUCCESS(status))
break;
BCryptDestroyHash(h_hash);
BCryptCloseAlgorithmProvider(h_alg, 0);
HeapFree(pheap, 0, cng_object);
h_alg = NULL;
h_hash = NULL;
status = BCryptOpenAlgorithmProvider(&h_alg, BCRYPT_RC4_ALGORITHM, NULL, 0);
if (!NT_SUCCESS(status))
break;
obj_sz = 0;
rlen = 0;
status = BCryptGetProperty(h_alg, BCRYPT_OBJECT_LENGTH, (PUCHAR)&obj_sz, sizeof(obj_sz), &rlen, 0);
if (!NT_SUCCESS(status))
break;
cng_object = HeapAlloc(pheap, HEAP_ZERO_MEMORY, obj_sz);
if (cng_object == NULL)
break;
status = BCryptGenerateSymmetricKey(h_alg, &h_rc4key, cng_object, obj_sz, hashdata, hdatasz, 0);
if (!NT_SUCCESS(status))
break;
decrypted = HeapAlloc(pheap, HEAP_ZERO_MEMORY, enc_data_size);
if (decrypted == NULL)
break;
rlen = 0;
status = BCryptEncrypt(h_rc4key, enc_data, enc_data_size, NULL, NULL, 0, decrypted, enc_data_size, &rlen, 0);
if (!NT_SUCCESS(status))
break;
bSuccess = FALSE;
enc_data_size = rlen;
rlen = 0;
extracted = SfcabExtractMemory(decrypted, enc_data_size, &rlen);
if (extracted) {
if (SfuWriteBufferToFile(OutputFile, extracted, rlen, FALSE, FALSE) == rlen) {
bSuccess = TRUE;
}
LocalFree(extracted);
}
else {
//failed to extract, drop cab as is
if (SfuWriteBufferToFile(OutputFile, decrypted, enc_data_size, FALSE, FALSE) == enc_data_size) {
bSuccess = TRUE;
}
}
if (bSuccess) {
SfcuiPrintText(g_ConOut,
T_SFDECRYPTED,
g_ConsoleOutput, FALSE);
SfcuiPrintText(g_ConOut,
OutputFile,
g_ConsoleOutput, FALSE);
}
} while (cond);
if (bSuccess == FALSE) {
SfcuiPrintText(g_ConOut,
T_SFDECRYPTFAIL,
g_ConsoleOutput, FALSE);
}
if (h_rc4key != NULL)
BCryptDestroyKey(h_rc4key);
if (h_hash != NULL)
BCryptDestroyHash(h_hash);
if (h_alg != NULL)
BCryptCloseAlgorithmProvider(h_alg, 0);
if (pheap != NULL)
HeapDestroy(pheap);
if (pdll != 0)
NtUnmapViewOfSection(NtCurrentProcess(), (PVOID)pdll);
return 0;
}
