windows: Use WINAPI call convention for Windows API callbacks

For x86_64 it does not actually matter, but for i686 builds the call convention
is different with WINAPI.

src/libcharon/plugins/kernel_iph/kernel_iph_net.c

@@ -355,9 +355,11 @@ typedef struct {
 /**
  * NotifyIpInterfaceChange() callback
  */
-static void change_interface(private_kernel_iph_net_t *this,
-					MIB_IPINTERFACE_ROW_FIXUP *row, MIB_NOTIFICATION_TYPE type)
+static void WINAPI change_interface(void *user, PMIB_IPINTERFACE_ROW row_badal,
+									MIB_NOTIFICATION_TYPE type)
 {
+	private_kernel_iph_net_t *this = user;
+	MIB_IPINTERFACE_ROW_FIXUP* row = (MIB_IPINTERFACE_ROW_FIXUP*)row_badal;
 	IP_ADAPTER_ADDRESSES addrs[64], *current;
 	ULONG res, size = sizeof(addrs);
 
@@ -757,7 +759,8 @@ kernel_iph_net_t *kernel_iph_net_create()
 		.mutex = mutex_create(MUTEX_TYPE_DEFAULT),
 		.ifaces = linked_list_create(),
 	);
-
+	/* PIPINTERFACE_CHANGE_CALLBACK is not using WINAPI in MinGW, which seems
+	 * to be wrong. Force a cast to our WINAPI call */
 	res = NotifyIpInterfaceChange(AF_UNSPEC, (void*)change_interface,
 								  this, TRUE, &this->changes);
 	if (res != NO_ERROR)

src/libcharon/plugins/kernel_wfp/kernel_wfp_ipsec.c

@@ -1545,9 +1545,9 @@ static traffic_selector_t *addr2ts(FWP_IP_VERSION version, void *data,
 /**
  * FwpmNetEventSubscribe0() callback
  */
-static void event_callback(private_kernel_wfp_ipsec_t *this,
-						   const FWPM_NET_EVENT1 *event)
+static void WINAPI event_callback(void *user, const FWPM_NET_EVENT1 *event)
 {
+	private_kernel_wfp_ipsec_t *this = user;
 	traffic_selector_t *local = NULL, *remote = NULL;
 	u_int8_t protocol = 0;
 	u_int16_t from_local = 0, to_local = 65535;
@@ -1610,7 +1610,7 @@ static bool register_events(private_kernel_wfp_ipsec_t *this)
 	DWORD res;
 
 	res = FwpmNetEventSubscribe0(this->handle, &subscription,
-								 (void*)event_callback, this, &this->event);
+								 event_callback, this, &this->event);
 	if (res != ERROR_SUCCESS)
 	{
 		DBG1(DBG_KNL, "registering for WFP events failed: 0x%08x", res);

src/libcharon/plugins/socket_win/socket_win_socket.c

@@ -75,14 +75,14 @@ struct private_socket_win_socket_t {
 	/**
 	 * WSASendMsg function
 	 */
-	int (*WSASendMsg)(SOCKET, LPWSAMSG, DWORD, LPDWORD,
-					  LPWSAOVERLAPPED, LPWSAOVERLAPPED_COMPLETION_ROUTINE);
+	int WINAPI (*WSASendMsg)(SOCKET, LPWSAMSG, DWORD, LPDWORD,
+					LPWSAOVERLAPPED, LPWSAOVERLAPPED_COMPLETION_ROUTINE);
 
 	/**
 	 * WSARecvMsg function
 	 */
-	int (*WSARecvMsg)(SOCKET, LPWSAMSG, LPDWORD,
-					  LPWSAOVERLAPPED, LPWSAOVERLAPPED_COMPLETION_ROUTINE);
+	int WINAPI (*WSARecvMsg)(SOCKET, LPWSAMSG, LPDWORD,
+					LPWSAOVERLAPPED, LPWSAOVERLAPPED_COMPLETION_ROUTINE);
 };
 
 METHOD(socket_t, receiver, status_t,