sctp: Implement socket option SCTP_GET_ASSOC_NUMBER

Implement socket option SCTP_GET_ASSOC_NUMBER of the latest ietf socket
extensions API draft.

  8.2.5.  Get the Current Number of Associations (SCTP_GET_ASSOC_NUMBER)

   This option gets the current number of associations that are attached
   to a one-to-many style socket.  The option value is an uint32_t.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/net/sctp/user.h b/include/net/sctp/user.h
index f205b10f0ab9..b259fc5798fb 100644
--- a/include/net/sctp/user.h
+++ b/include/net/sctp/user.h
@@ -118,6 +118,8 @@ enum sctp_optname {
 #define SCTP_PEER_AUTH_CHUNKS SCTP_PEER_AUTH_CHUNKS
         SCTP_LOCAL_AUTH_CHUNKS,         /* Read only */
 #define SCTP_LOCAL_AUTH_CHUNKS SCTP_LOCAL_AUTH_CHUNKS
+        SCTP_GET_ASSOC_NUMBER,          /* Read only */
+#define SCTP_GET_ASSOC_NUMBER SCTP_GET_ASSOC_NUMBER
 
 
         /* Internal Socket Options. Some of the sctp library functions are