Function DetourCopyPayloadToProcessEx

lib_fiber/cpp/src/detours/creatwth.cpp:1023–1127

_Success_(return != NULL)
PVOID WINAPI DetourCopyPayloadToProcessEx(_In_ HANDLE hProcess,
                                          _In_ REFGUID rguid,
                                          _In_reads_bytes_(cbData) LPCVOID pvData,
                                          _In_ DWORD cbData)
{
    if (hProcess == NULL) {
        SetLastError(ERROR_INVALID_HANDLE);
        return NULL;
    }

    DWORD cbTotal = (sizeof(IMAGE_DOS_HEADER) +
                     sizeof(IMAGE_NT_HEADERS) +
                     sizeof(IMAGE_SECTION_HEADER) +
                     sizeof(DETOUR_SECTION_HEADER) +
                     sizeof(DETOUR_SECTION_RECORD) +
                     cbData);

    PBYTE pbBase = (PBYTE)VirtualAllocEx(hProcess, NULL, cbTotal,
                                         MEM_COMMIT, PAGE_READWRITE);
    if (pbBase == NULL) {
        DETOUR_TRACE(("VirtualAllocEx(%lu) failed: %lu\n", cbTotal, GetLastError()));
        return NULL;
    }

    // As you can see in the following code,
    // the memory layout of the payload range "[pbBase, pbBase+cbTotal]" is a PE executable file,
    // so DetourFreePayload can use "DetourGetContainingModule(Payload pointer)" to get the above "pbBase" pointer,
    // pbBase: the memory block allocated by VirtualAllocEx will be released in DetourFreePayload by VirtualFree.

    PBYTE pbTarget = pbBase;
    IMAGE_DOS_HEADER idh;
    IMAGE_NT_HEADERS inh;
    IMAGE_SECTION_HEADER ish;
    DETOUR_SECTION_HEADER dsh;
    DETOUR_SECTION_RECORD dsr;
    SIZE_T cbWrote = 0;

    ZeroMemory(&idh, sizeof(idh));
    idh.e_magic = IMAGE_DOS_SIGNATURE;
    idh.e_lfanew = sizeof(idh);
    if (!WriteProcessMemory(hProcess, pbTarget, &idh, sizeof(idh), &cbWrote) ||
        cbWrote != sizeof(idh)) {
        DETOUR_TRACE(("WriteProcessMemory(idh) failed: %lu\n", GetLastError()));
        return NULL;
    }
    pbTarget += sizeof(idh);

    ZeroMemory(&inh, sizeof(inh));
    inh.Signature = IMAGE_NT_SIGNATURE;
    inh.FileHeader.SizeOfOptionalHeader = sizeof(inh.OptionalHeader);
    inh.FileHeader.Characteristics = IMAGE_FILE_DLL;
    inh.FileHeader.NumberOfSections = 1;
    inh.OptionalHeader.Magic = IMAGE_NT_OPTIONAL_HDR_MAGIC;
    if (!WriteProcessMemory(hProcess, pbTarget, &inh, sizeof(inh), &cbWrote) ||
        cbWrote != sizeof(inh)) {
        return NULL;
    }
    pbTarget += sizeof(inh);