Added support for sending/receiving ancillary data. The protocol modules

have two more optional hooks for attaching supplied ancillary data to a
net_buffer and for processing received ancillary data. Not sure, if that
is flexible enough for all kinds of ancillary data, but it is for
SCM_RIGHTS and also should for SCM_CRED[ENTIAL]S (if we ever decide to
implement one of those) -- don't know any other types on other protocol
levels.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24941 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/private/net/net_protocol.h

@@ -68,6 +68,12 @@ struct net_protocol_module_info {
 	status_t	(*error)(uint32 code, net_buffer *data);
 	status_t	(*error_reply)(net_protocol *self, net_buffer *causedError,
 					uint32 code, void *errorData);
+
+	status_t	(*attach_ancillary_data)(net_protocol *self, net_buffer *buffer,
+					const cmsghdr *header);
+	ssize_t		(*process_ancillary_data)(net_protocol *self,
+					const ancillary_data_header *header, const void *data,
+					void *buffer, size_t bufferSize);
 };
 
 #endif	// NET_PROTOCOL_H