[SCTP] shutdown() support for TCP-style sockets.

net/sctp/ipv6.c

@@ -520,6 +520,7 @@ struct sock *sctp_v6_create_accept_sk(struct sock *sk,
 	newsk->family = PF_INET6;
 	newsk->protocol = IPPROTO_SCTP;
 	newsk->backlog_rcv = sk->prot->backlog_rcv;
+	newsk->shutdown = sk->shutdown;
 
 	newsctp6sk = (struct sctp6_sock *)newsk;
 	newsctp6sk->pinet6 = &newsctp6sk->inet6;

net/sctp/protocol.c

@@ -515,6 +515,7 @@ struct sock *sctp_v4_create_accept_sk(struct sock *sk,
 	newsk->prot = sk->prot;
 	newsk->no_check = sk->no_check;
 	newsk->reuse = sk->reuse;
+	newsk->shutdown = sk->shutdown;
 
 	newsk->destruct = inet_sock_destruct;
 	newsk->zapped = 0;

net/sctp/sm_sideeffect.c

@@ -617,8 +617,23 @@ static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, struct sctp_association *as
 	asoc->state = state;
 	asoc->state_timestamp = jiffies;
 
+	if (SCTP_SOCKET_TCP == sp->type) {
+		/* Change the sk->state of a TCP-style socket that has 
+		 * sucessfully completed a connect() call.
+		 */
+		if ((SCTP_STATE_ESTABLISHED == asoc->state) &&
+		    (SCTP_SS_CLOSED == sk->state))
+			sk->state = SCTP_SS_ESTABLISHED;
+
+		/* Set the RCV_SHUTDOWN flag when a SHUTDOWN is received. */
+		if (SCTP_STATE_SHUTDOWN_RECEIVED == asoc->state)
+			sk->shutdown |= RCV_SHUTDOWN;
+
+	}
+
 	if ((SCTP_STATE_ESTABLISHED == asoc->state) ||
-	    (SCTP_STATE_CLOSED == asoc->state)) {
+	    (SCTP_STATE_CLOSED == asoc->state) ||
+	    (SCTP_STATE_SHUTDOWN_RECEIVED == asoc->state)) {
 		/* Wake up any processes waiting in the asoc's wait queue in
 		 * sctp_wait_for_connect() or sctp_wait_for_sndbuf().
 	 	 */
@@ -634,13 +649,6 @@ static void sctp_cmd_new_state(sctp_cmd_seq_t *cmds, struct sctp_association *as
 		if (SCTP_SOCKET_UDP != sp->type)
 			sk->state_change(sk);
 	}
-
-	/* Change the sk->state of a TCP-style socket that has sucessfully
-	 * completed a connect() call.
-	 */
-	if ((SCTP_STATE_ESTABLISHED == asoc->state) &&
-	    (SCTP_SOCKET_TCP == sp->type) && (SCTP_SS_CLOSED == sk->state))
-	    sk->state = SCTP_SS_ESTABLISHED;
 }
 
 /* These three macros allow us to pull the debugging code out of the

net/sctp/socket.c

@@ -1864,11 +1864,38 @@ SCTP_STATIC int sctp_destroy_sock(struct sock *sk)
 	return 0;
 }
 
-/* FIXME: Comments needed.  */
+/* API 4.1.7 shutdown() - TCP Style Syntax
+ *     int shutdown(int socket, int how);
+ *
+ *     sd      - the socket descriptor of the association to be closed.
+ *     how     - Specifies the type of shutdown.  The  values  are
+ *               as follows:
+ *               SHUT_RD
+ *                     Disables further receive operations. No SCTP
+ *                     protocol action is taken.
+ *               SHUT_WR
+ *                     Disables further send operations, and initiates
+ *                     the SCTP shutdown sequence.
+ *               SHUT_RDWR
+ *                     Disables further send  and  receive  operations
+ *                     and initiates the SCTP shutdown sequence.
+ */
 SCTP_STATIC void sctp_shutdown(struct sock *sk, int how)
 {
-	/* UDP-style sockets do not support shutdown. */
-	/* STUB */
+	struct sctp_endpoint *ep;
+	struct sctp_association *asoc;
+
+	if (SCTP_SOCKET_TCP != sctp_sk(sk)->type)
+		return;
+
+	if (how & SEND_SHUTDOWN) {
+		ep = sctp_sk(sk)->ep;
+		if (!list_empty(&ep->asocs)) {
+			asoc = list_entry(ep->asocs.next,
+					  struct sctp_association, asocs);
+			sctp_primitive_SHUTDOWN(asoc, NULL);
+		}
+	}
 }
 
 /* 7.2.1 Association Status (SCTP_STATUS)
@@ -3145,6 +3172,9 @@ static struct sk_buff *sctp_skb_recv_datagram(struct sock *sk, int flags,
 		if (skb)
 			return skb;
 
+		if (sk->shutdown & RCV_SHUTDOWN)
+			break;
+
 		/* User doesn't want to wait.  */
 		error = -EAGAIN;
 		if (!timeo)
@@ -3379,6 +3409,8 @@ static int sctp_wait_for_connect(struct sctp_association *asoc, long *timeo_p)
 		__set_current_state(TASK_INTERRUPTIBLE);
 		if (!*timeo_p)
 			goto do_nonblock;
+		if (sk->shutdown & RCV_SHUTDOWN)
+			break;
 		if (sk->err || asoc->state >= SCTP_STATE_SHUTDOWN_PENDING ||
 		    asoc->base.dead)
 			goto do_error;