rxrpc: Be more selective about the types of received packets we accept

Currently, received RxRPC packets outside the range 1-13 are rejected.
There are, however, holes in the range that should also be rejected - plus
at least one type we don't yet support - so reject these also.

Signed-off-by: David Howells <dhowells@redhat.com>
diff --git a/include/rxrpc/packet.h b/include/rxrpc/packet.h
index de1e679..9ebab3a 100644
--- a/include/rxrpc/packet.h
+++ b/include/rxrpc/packet.h
@@ -70,6 +70,17 @@
 
 extern const char *rxrpc_pkts[];
 
+#define RXRPC_SUPPORTED_PACKET_TYPES (			\
+		(1 << RXRPC_PACKET_TYPE_DATA) |		\
+		(1 << RXRPC_PACKET_TYPE_ACK) |		\
+		(1 << RXRPC_PACKET_TYPE_BUSY) |		\
+		(1 << RXRPC_PACKET_TYPE_ABORT) |	\
+		(1 << RXRPC_PACKET_TYPE_ACKALL) |	\
+		(1 << RXRPC_PACKET_TYPE_CHALLENGE) |	\
+		(1 << RXRPC_PACKET_TYPE_RESPONSE) |	\
+		/*(1 << RXRPC_PACKET_TYPE_DEBUG) | */	\
+		(1 << RXRPC_PACKET_TYPE_VERSION))
+
 /*****************************************************************************/
 /*
  * jumbo packet secondary header