rxrpc: Display security params in the afs_cb_call tracepoint

Make the afs_cb_call tracepoint display some security parameters to make
debugging easier.

Signed-off-by: David Howells <[email protected]>
cc: Marc Dionne <[email protected]>
cc: Simon Horman <[email protected]>
cc: [email protected]
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jakub Kicinski <[email protected]>

Author: dhowells

Documentation/networking/rxrpc.rst

@@ -1178,6 +1178,7 @@ API Function Reference
 ======================
 
 .. kernel-doc:: net/rxrpc/af_rxrpc.c
+.. kernel-doc:: net/rxrpc/call_object.c
 .. kernel-doc:: net/rxrpc/key.c
 .. kernel-doc:: net/rxrpc/oob.c
 .. kernel-doc:: net/rxrpc/peer_object.c

fs/afs/internal.h

@@ -176,8 +176,10 @@ struct afs_call {
 	bool			intr;		/* T if interruptible */
 	bool			unmarshalling_error; /* T if an unmarshalling error occurred */
 	bool			responded;	/* Got a response from the call (may be abort) */
+	u8			security_ix;	/* Security class */
 	u16			service_id;	/* Actual service ID (after upgrade) */
 	unsigned int		debug_id;	/* Trace ID */
+	u32			enctype;	/* Security encoding type */
 	u32			operation_ID;	/* operation ID for an incoming call */
 	u32			count;		/* count for use in unmarshalling */
 	union {					/* place to extract temporary data */

fs/afs/rxrpc.c

@@ -813,6 +813,10 @@ static int afs_deliver_cm_op_id(struct afs_call *call)
 	if (!afs_cm_incoming_call(call))
 		return -ENOTSUPP;
 
+	call->security_ix = rxrpc_kernel_query_call_security(call->rxcall,
+							     &call->service_id,
+							     &call->enctype);
+
 	trace_afs_cb_call(call);
 	call->work.func = call->type->work;
 

include/net/af_rxrpc.h

@@ -112,5 +112,7 @@ int rxkad_kernel_respond_to_challenge(struct sk_buff *challenge);
 u32 rxgk_kernel_query_challenge(struct sk_buff *challenge);
 int rxgk_kernel_respond_to_challenge(struct sk_buff *challenge,
 				     struct krb5_buffer *appdata);
+u8 rxrpc_kernel_query_call_security(struct rxrpc_call *call,
+				    u16 *_service_id, u32 *_enctype);
 
 #endif /* _NET_RXRPC_H */

include/trace/events/afs.h

@@ -663,19 +663,26 @@ TRACE_EVENT(afs_cb_call,
 		    __field(unsigned int,		call)
 		    __field(u32,			op)
 		    __field(u16,			service_id)
+		    __field(u8,				security_ix)
+		    __field(u32,			enctype)
 			     ),
 
 	    TP_fast_assign(
 		    __entry->call	= call->debug_id;
 		    __entry->op		= call->operation_ID;
 		    __entry->service_id	= call->service_id;
+		    __entry->security_ix = call->security_ix;
+		    __entry->enctype	= call->enctype;
 			   ),
 
-	    TP_printk("c=%08x %s",
+	    TP_printk("c=%08x %s sv=%u sx=%u en=%u",
 		      __entry->call,
 		      __entry->service_id == 2501 ?
 		      __print_symbolic(__entry->op, yfs_cm_operations) :
-		      __print_symbolic(__entry->op, afs_cm_operations))
+		      __print_symbolic(__entry->op, afs_cm_operations),
+		      __entry->service_id,
+		      __entry->security_ix,
+		      __entry->enctype)
 	    );
 
 TRACE_EVENT(afs_call,

net/rxrpc/ar-internal.h

@@ -740,6 +740,7 @@ struct rxrpc_call {
 	u32			call_id;	/* call ID on connection  */
 	u32			cid;		/* connection ID plus channel index */
 	u32			security_level;	/* Security level selected */
+	u32			security_enctype; /* Security-specific encoding type (or 0) */
 	int			debug_id;	/* debug ID for printks */
 	unsigned short		rx_pkt_offset;	/* Current recvmsg packet offset */
 	unsigned short		rx_pkt_len;	/* Current recvmsg packet len */

net/rxrpc/call_object.c

@@ -760,3 +760,23 @@ void rxrpc_destroy_all_calls(struct rxrpc_net *rxnet)
 	atomic_dec(&rxnet->nr_calls);
 	wait_var_event(&rxnet->nr_calls, !atomic_read(&rxnet->nr_calls));
 }
+
+/**
+ * rxrpc_kernel_query_call_security - Query call's security parameters
+ * @call: The call to query
+ * @_service_id: Where to return the service ID
+ * @_enctype: Where to return the "encoding type"
+ *
+ * This queries the security parameters of a call, setting *@_service_id and
+ * *@_enctype and returning the security class.
+ *
+ * Return: The security class protocol number.
+ */
+u8 rxrpc_kernel_query_call_security(struct rxrpc_call *call,
+				    u16 *_service_id, u32 *_enctype)
+{
+	*_service_id = call->dest_srx.srx_service;
+	*_enctype = call->security_enctype;
+	return call->security_ix;
+}
+EXPORT_SYMBOL(rxrpc_kernel_query_call_security);

net/rxrpc/rxgk.c

@@ -443,6 +443,7 @@ static int rxgk_secure_packet(struct rxrpc_call *call, struct rxrpc_txbuf *txb)
 	if (ret < 0)
 		return ret;
 
+	call->security_enctype = gk->krb5->etype;
 	txb->cksum = htons(gk->key_number);
 
 	switch (call->conn->security_level) {
@@ -590,6 +591,7 @@ static int rxgk_verify_packet(struct rxrpc_call *call, struct sk_buff *skb)
 		}
 	}
 
+	call->security_enctype = gk->krb5->etype;
 	switch (call->conn->security_level) {
 	case RXRPC_SECURITY_PLAIN:
 		return 0;