sctp: add stream reconf primitive

This patch is to add a primitive based on sctp primitive frame for
sending stream reconf request. It works as the other primitives,
and create a SCTP_CMD_REPLY command to send the request chunk out.

sctp_primitive_RECONF would be the api to send a reconf request
chunk.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/sctp/constants.h

@@ -114,9 +114,10 @@ typedef enum {
 	SCTP_PRIMITIVE_SEND,
 	SCTP_PRIMITIVE_REQUESTHEARTBEAT,
 	SCTP_PRIMITIVE_ASCONF,
+	SCTP_PRIMITIVE_RECONF,
 } sctp_event_primitive_t;
 
-#define SCTP_EVENT_PRIMITIVE_MAX	SCTP_PRIMITIVE_ASCONF
+#define SCTP_EVENT_PRIMITIVE_MAX	SCTP_PRIMITIVE_RECONF
 #define SCTP_NUM_PRIMITIVE_TYPES	(SCTP_EVENT_PRIMITIVE_MAX + 1)
 
 /* We define here a utility type for manipulating subtypes.

include/net/sctp/sctp.h

@@ -141,6 +141,8 @@ int sctp_primitive_ABORT(struct net *, struct sctp_association *, void *arg);
 int sctp_primitive_SEND(struct net *, struct sctp_association *, void *arg);
 int sctp_primitive_REQUESTHEARTBEAT(struct net *, struct sctp_association *, void *arg);
 int sctp_primitive_ASCONF(struct net *, struct sctp_association *, void *arg);
+int sctp_primitive_RECONF(struct net *net, struct sctp_association *asoc,
+			  void *arg);
 
 /*
  * sctp/input.c

include/net/sctp/sm.h

@@ -157,6 +157,7 @@ sctp_state_fn_t sctp_sf_error_shutdown;
 sctp_state_fn_t sctp_sf_ignore_primitive;
 sctp_state_fn_t sctp_sf_do_prm_requestheartbeat;
 sctp_state_fn_t sctp_sf_do_prm_asconf;
+sctp_state_fn_t sctp_sf_do_prm_reconf;
 
 /* Prototypes for other event state functions.  */
 sctp_state_fn_t sctp_sf_do_no_pending_tsn;

net/sctp/primitive.c

@@ -211,3 +211,6 @@ DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
 */
 
 DECLARE_PRIMITIVE(ASCONF);
+
+/* RE-CONFIG 5.1 */
+DECLARE_PRIMITIVE(RECONF);

net/sctp/sm_statefuns.c

@@ -5185,6 +5185,19 @@ sctp_disposition_t sctp_sf_do_prm_asconf(struct net *net,
 	return SCTP_DISPOSITION_CONSUME;
 }
 
+/* RE-CONFIG Section 5.1 RECONF Chunk Procedures */
+sctp_disposition_t sctp_sf_do_prm_reconf(struct net *net,
+					 const struct sctp_endpoint *ep,
+					 const struct sctp_association *asoc,
+					 const sctp_subtype_t type,
+					 void *arg, sctp_cmd_seq_t *commands)
+{
+	struct sctp_chunk *chunk = arg;
+
+	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk));
+	return SCTP_DISPOSITION_CONSUME;
+}
+
 /*
  * Ignore the primitive event
  *

net/sctp/sm_statetable.c

@@ -643,6 +643,25 @@ chunk_event_table_unknown[SCTP_STATE_NUM_STATES] = {
 	TYPE_SCTP_FUNC(sctp_sf_error_shutdown), \
 } /* TYPE_SCTP_PRIMITIVE_ASCONF */
 
+#define TYPE_SCTP_PRIMITIVE_RECONF { \
+	/* SCTP_STATE_CLOSED */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_COOKIE_WAIT */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_COOKIE_ECHOED */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_ESTABLISHED */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_PENDING */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_RECEIVED */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_ACK_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_shutdown), \
+} /* TYPE_SCTP_PRIMITIVE_RECONF */
+
 /* The primary index for this table is the primitive type.
  * The secondary index for this table is the state.
  */
@@ -653,6 +672,7 @@ static const sctp_sm_table_entry_t primitive_event_table[SCTP_NUM_PRIMITIVE_TYPE
 	TYPE_SCTP_PRIMITIVE_SEND,
 	TYPE_SCTP_PRIMITIVE_REQUESTHEARTBEAT,
 	TYPE_SCTP_PRIMITIVE_ASCONF,
+	TYPE_SCTP_PRIMITIVE_RECONF,
 };
 
 #define TYPE_SCTP_OTHER_NO_PENDING_TSN  { \