void UsbDeviceList::AddInterfaceFilter(LPCWSTR name, LPCWSTR value)
{
// Filter name must be unique
for (DWORD i = 0; i < mNumInterfaceFilters; i++) {
if (wcscmp(name, mInterfaceFilters[i].name) == 0) {
IFACEFILTER_MSG((TEXT("USBKWrapperDrv: Ignoring duplicate interface filter %s\r\n"), name));
return;
}
}
// Parse filter string "bInterfaceClass:bInterfaceSubclass:bInterfaceProtocol"
// Any field can be '*', represent this "dont-care" as USB_NO_INFO.
INTERFACE_FILTER_FIELD bInterfaceClass, bInterfaceSubClass, bInterfaceProtocol;
DWORD nextOffset, result;
result = FindNextInterfaceFilterField(value, 0, &nextOffset, &bInterfaceClass);
result |= FindNextInterfaceFilterField(value, nextOffset, &nextOffset, &bInterfaceSubClass);
result |= FindNextInterfaceFilterField(value, nextOffset, &nextOffset, &bInterfaceProtocol);
if (result) {
IFACEFILTER_MSG((TEXT("USBKWrapperDrv: Parse error for interface filter %s: %s\r\n"), name, value));
return;
}
// Now check for optional idVendor/idProduct fields (initialised by FindNextInterfaceFilterToken())
INTERFACE_FILTER_FIELD idVendor, idProduct;
FindNextInterfaceFilterField(value, nextOffset, &nextOffset, &idVendor);
FindNextInterfaceFilterField(value, nextOffset, &nextOffset, &idProduct);
PWCHAR filterName = (PWCHAR) malloc(sizeof(WCHAR)*(wcslen(name)+1));;
if (!filterName) {
ERROR_MSG((TEXT("USBKWrapperDrv!UsbDeviceList::AddInterfaceFilter() - Out of memory allocating filter name\r\n")));
return;
}
wcscpy(filterName, name);
// Finally, check for any optional flags (we can switch to a more advanced
// flag parsing strategy if and when we add more flags in the future).
BOOL noAttach = FALSE;
if (wcsstr(value, L";NO_ATTACH") != NULL) {
noAttach = TRUE;
}
INTERFACE_FILTER* newFilterList = (INTERFACE_FILTER*) realloc(mInterfaceFilters, sizeof(INTERFACE_FILTER)*(mNumInterfaceFilters+1));
if (!newFilterList) {
ERROR_MSG((TEXT("USBKWrapperDrv!UsbDeviceList::AddInterfaceFilter() - Out of memory reallocating filter list\r\n")));
free(filterName);
return;
}
// Append filter to list
mInterfaceFilters = newFilterList;
mInterfaceFilters[mNumInterfaceFilters].name = filterName;
mInterfaceFilters[mNumInterfaceFilters].bInterfaceClass = bInterfaceClass;
mInterfaceFilters[mNumInterfaceFilters].bInterfaceSubClass = bInterfaceSubClass;
mInterfaceFilters[mNumInterfaceFilters].bInterfaceProtocol = bInterfaceProtocol;
mInterfaceFilters[mNumInterfaceFilters].idVendor = idVendor;
mInterfaceFilters[mNumInterfaceFilters].idProduct = idProduct;
mInterfaceFilters[mNumInterfaceFilters].noAttach = noAttach;
LogFilter(TEXT("USBKWrapperDrv: Added interface filter"), &mInterfaceFilters[mNumInterfaceFilters]);
mNumInterfaceFilters++;
}
void UsbDeviceList::FetchInterfaceFilters(LPCUSB_FUNCS lpUsbFuncs,
LPCWSTR szUniqueDriverId)
{
HKEY key;
LONG result;
DWORD numValues = 0, maxNameLen = 0, maxValueLen = 0;
DWORD valueType;
PWCHAR nameBuf;
PBYTE valueBuf;
// We do not support dynamic updating of the filter list
if (mInterfaceFilters) {
return;
}
key = lpUsbFuncs->lpOpenClientRegistyKey(szUniqueDriverId);
if (!key) {
ERROR_MSG((TEXT("USBKWrapperDrv!UsbDeviceList::FetchInterfaceFilters() - Failed to open client registry key\r\n")));
return;
}
result = RegQueryInfoKey(key, NULL, NULL, NULL, NULL, NULL, NULL,
&numValues, &maxNameLen, &maxValueLen, NULL, NULL);
if (result != ERROR_SUCCESS) {
ERROR_MSG((TEXT("USBKWrapperDrv!UsbDeviceList::FetchInterfaceFilters() - Failed to query key info: error %i\r\n"), result));
RegCloseKey(key);
return;
}
nameBuf = new (std::nothrow) WCHAR[maxNameLen+1];
valueBuf = new (std::nothrow) BYTE[maxValueLen];
if (!nameBuf || !valueBuf) {
ERROR_MSG((TEXT("USBKWrapperDrv!UsbDeviceList::FetchInterfaceFilters() - Out of memory allocating buffers\r\n")));
delete[] nameBuf;
delete[] valueBuf;
RegCloseKey(key);
return;
}
for (DWORD index = 0; index < numValues && result == ERROR_SUCCESS; index++) {
DWORD nameBufSize = maxNameLen + 1;
DWORD valueBufSize = maxValueLen;
result = RegEnumValue(key, index, nameBuf, &nameBufSize, NULL, &valueType,
valueBuf, &valueBufSize);
if (result == ERROR_SUCCESS) {
// Pay attention only to unicode strings (REG_SZ) whose name has the
// InterfaceFilter_ prefix
if (nameBufSize > 16 && wcsncmp(nameBuf, TEXT("InterfaceFilter_"), 16) == 0 &&
valueType == REG_SZ) {
AddInterfaceFilter(&nameBuf[16], (LPCWSTR) valueBuf);
}
}
}
// Log out the interface filters we have, in priority order
PFILTER_NODE next = mInterfaceFilters;
while(next) {
LogFilter(TEXT("USBKWrapperDrv: Added interface filter"), &next->filter);
next = next->next;
}
delete[] nameBuf;
delete[] valueBuf;
RegCloseKey(key);
}
