Dexter retrieve active network interface IP address snippet

libsysteminfo.cpp

//https://github.com/twelvesec/dexter
//GNU General Public License v3.0
//@maldevel

//...

std::string libsysteminfo::get_active_netface_ip(void) {
	std::string ipaddress = "";
	DWORD size = 0;
	ULONG result = 0;
	PIP_ADAPTER_ADDRESSES aAddr = NULL;
	PIP_ADAPTER_ADDRESSES aAddrIndex = NULL;
	PIP_ADAPTER_UNICAST_ADDRESS aAddrUnicast = NULL;
	WSADATA wsaData;
	WCHAR *buf;
	unsigned long bufSize = 50; //xxx.xxx.xxx.xxx

	if ((result = GetAdaptersAddresses(0, 0, 0, 0, &size)) != ERROR_BUFFER_OVERFLOW) {
		return "";
	}

	if ((aAddr = (PIP_ADAPTER_ADDRESSES)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, size)) == NULL) {
		return "";
	}

	if (GetAdaptersAddresses(AF_INET, GAA_FLAG_INCLUDE_PREFIX, 0, aAddr, &size) != NO_ERROR) {
		HeapFree(GetProcessHeap(), 0, aAddr);
		aAddr = NULL;
		return "";
	}

	if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0) {
		HeapFree(GetProcessHeap(), 0, aAddr);
		aAddr = NULL;
		return "";
	}

	aAddrIndex = aAddr;
	std::wstring tmp;

	while (aAddrIndex) {
		if ((aAddrIndex->IfType == 6 || aAddrIndex->IfType == 71) && aAddrIndex->OperStatus == 1 &&
			std::wstring(aAddrIndex->Description).find(L"Hyper-V") == std::string::npos &&
			std::wstring(aAddrIndex->Description).find(L"VirtualBox") == std::string::npos &&
			std::wstring(aAddrIndex->Description).find(L"VMware") == std::string::npos) {

			if ((aAddrUnicast = aAddrIndex->FirstUnicastAddress) != NULL) {

				if ((buf = (WCHAR*)HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, bufSize * sizeof(WCHAR))) == NULL) {
					continue;
				}

				if (WSAAddressToStringW(aAddrUnicast->Address.lpSockaddr,
					aAddrUnicast->Address.iSockaddrLength, NULL, buf, &bufSize) == 0) {
					tmp += std::wstring(buf) + L" ";
					HeapFree(GetProcessHeap(), 0, buf);
					buf = NULL;
				}

			}
		}
		aAddrIndex = aAddrIndex->Next;
	}

	HeapFree(GetProcessHeap(), 0, aAddr);
	aAddr = NULL;

	WSACleanup();

	tmp = tmp.substr(0, tmp.size() - 1);
	ipaddress = std::string(tmp.begin(), tmp.end());
	return ipaddress;
}