Merge branch 'sctp-add-subscribe-per-asoc-and-sockopt-SCTP_EVENT'

Xin Long says:

====================
sctp: add subscribe per asoc and sockopt SCTP_EVENT

This patchset mainly adds the Event Subscription sockopt described in
rfc6525#section-6.2:

"Subscribing to events as described in [RFC6458] uses a setsockopt()
call with the SCTP_EVENT socket option.  This option takes the
following structure, which specifies the association, the event type
(using the same value found in the event type field), and an on/off
boolean.

  struct sctp_event {
    sctp_assoc_t se_assoc_id;
    uint16_t     se_type;
    uint8_t      se_on;
  };

The user fills in the se_type field with the same value found in the
strreset_type field, i.e., SCTP_STREAM_RESET_EVENT.  The user will
also fill in the se_assoc_id field with either the association to set
this event on (this field is ignored for one-to-one style sockets) or
one of the reserved constant values defined in [RFC6458].  Finally,
the se_on field is set with a 1 to enable the event or a 0 to disable
the event."

As for the old SCTP_EVENTS Option with struct sctp_event_subscribe,
it's being DEPRECATED.

v1->v2:
  - fix some key word in changelog that triggerred the filters at
    vger.kernel.org.
v2->v3:
  - fix an array out of bounds noticed by Neil in patch 1/4.
====================

Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 117 insertions, 8 deletions

diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 5299add6d7aa..e16c090e89f0 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -2230,7 +2230,7 @@ static int sctp_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 	if (sp->recvrcvinfo)
 		sctp_ulpevent_read_rcvinfo(event, msg);
 	/* Check if we allow SCTP_SNDRCVINFO. */
-	if (sp->subscribe.sctp_data_io_event)
+	if (sctp_ulpevent_type_enabled(sp->subscribe, SCTP_DATA_IO_EVENT))
 		sctp_ulpevent_read_sndrcvinfo(event, msg);
 
 	err = copied;
@@ -2304,22 +2304,33 @@ static int sctp_setsockopt_disable_fragments(struct sock *sk,
 static int sctp_setsockopt_events(struct sock *sk, char __user *optval,
 				  unsigned int optlen)
 {
+	struct sctp_event_subscribe subscribe;
+	__u8 *sn_type = (__u8 *)&subscribe;
+	struct sctp_sock *sp = sctp_sk(sk);
 	struct sctp_association *asoc;
-	struct sctp_ulpevent *event;
+	int i;
 
 	if (optlen > sizeof(struct sctp_event_subscribe))
 		return -EINVAL;
-	if (copy_from_user(&sctp_sk(sk)->subscribe, optval, optlen))
+
+	if (copy_from_user(&subscribe, optval, optlen))
 		return -EFAULT;
 
+	for (i = 0; i < optlen; i++)
+		sctp_ulpevent_type_set(&sp->subscribe, SCTP_SN_TYPE_BASE + i,
+				       sn_type[i]);
+
+	list_for_each_entry(asoc, &sp->ep->asocs, asocs)
+		asoc->subscribe = sctp_sk(sk)->subscribe;
+
 	/* At the time when a user app subscribes to SCTP_SENDER_DRY_EVENT,
 	 * if there is no data to be sent or retransmit, the stack will
 	 * immediately send up this notification.
 	 */
-	if (sctp_ulpevent_type_enabled(SCTP_SENDER_DRY_EVENT,
-				       &sctp_sk(sk)->subscribe)) {
-		asoc = sctp_id2assoc(sk, 0);
+	if (sctp_ulpevent_type_enabled(sp->subscribe, SCTP_SENDER_DRY_EVENT)) {
+		struct sctp_ulpevent *event;
 
+		asoc = sctp_id2assoc(sk, 0);
 		if (asoc && sctp_outq_is_empty(&asoc->outqueue)) {
 			event = sctp_ulpevent_make_sender_dry_event(asoc,
 					GFP_USER | __GFP_NOWARN);
@@ -4277,6 +4288,57 @@ static int sctp_setsockopt_reuse_port(struct sock *sk, char __user *optval,
 	return 0;
 }
 
+static int sctp_setsockopt_event(struct sock *sk, char __user *optval,
+				 unsigned int optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_ulpevent *event;
+	struct sctp_event param;
+	int retval = 0;
+
+	if (optlen < sizeof(param)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	optlen = sizeof(param);
+	if (copy_from_user(&param, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (param.se_type < SCTP_SN_TYPE_BASE ||
+	    param.se_type > SCTP_SN_TYPE_MAX) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	asoc = sctp_id2assoc(sk, param.se_assoc_id);
+	if (!asoc) {
+		sctp_ulpevent_type_set(&sctp_sk(sk)->subscribe,
+				       param.se_type, param.se_on);
+		goto out;
+	}
+
+	sctp_ulpevent_type_set(&asoc->subscribe, param.se_type, param.se_on);
+
+	if (param.se_type == SCTP_SENDER_DRY_EVENT && param.se_on) {
+		if (sctp_outq_is_empty(&asoc->outqueue)) {
+			event = sctp_ulpevent_make_sender_dry_event(asoc,
+					GFP_USER | __GFP_NOWARN);
+			if (!event) {
+				retval = -ENOMEM;
+				goto out;
+			}
+
+			asoc->stream.si->enqueue_event(&asoc->ulpq, event);
+		}
+	}
+
+out:
+	return retval;
+}
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -4474,6 +4536,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_REUSE_PORT:
 		retval = sctp_setsockopt_reuse_port(sk, optval, optlen);
 		break;
+	case SCTP_EVENT:
+		retval = sctp_setsockopt_event(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
@@ -4722,7 +4787,7 @@ static int sctp_init_sock(struct sock *sk)
 	/* Initialize default event subscriptions. By default, all the
 	 * options are off.
 	 */
-	memset(&sp->subscribe, 0, sizeof(struct sctp_event_subscribe));
+	sp->subscribe = 0;
 
 	/* Default Peer Address Parameters.  These defaults can
 	 * be modified via SCTP_PEER_ADDR_PARAMS
@@ -5267,14 +5332,24 @@ static int sctp_getsockopt_disable_fragments(struct sock *sk, int len,
 static int sctp_getsockopt_events(struct sock *sk, int len, char __user *optval,
 				  int __user *optlen)
 {
+	struct sctp_event_subscribe subscribe;
+	__u8 *sn_type = (__u8 *)&subscribe;
+	int i;
+
 	if (len == 0)
 		return -EINVAL;
 	if (len > sizeof(struct sctp_event_subscribe))
 		len = sizeof(struct sctp_event_subscribe);
 	if (put_user(len, optlen))
 		return -EFAULT;
-	if (copy_to_user(optval, &sctp_sk(sk)->subscribe, len))
+
+	for (i = 0; i < len; i++)
+		sn_type[i] = sctp_ulpevent_type_enabled(sctp_sk(sk)->subscribe,
+							SCTP_SN_TYPE_BASE + i);
+
+	if (copy_to_user(optval, &subscribe, len))
 		return -EFAULT;
+
 	return 0;
 }
 
@@ -7409,6 +7484,37 @@ static int sctp_getsockopt_reuse_port(struct sock *sk, int len,
 	return 0;
 }
 
+static int sctp_getsockopt_event(struct sock *sk, int len, char __user *optval,
+				 int __user *optlen)
+{
+	struct sctp_association *asoc;
+	struct sctp_event param;
+	__u16 subscribe;
+
+	if (len < sizeof(param))
+		return -EINVAL;
+
+	len = sizeof(param);
+	if (copy_from_user(&param, optval, len))
+		return -EFAULT;
+
+	if (param.se_type < SCTP_SN_TYPE_BASE ||
+	    param.se_type > SCTP_SN_TYPE_MAX)
+		return -EINVAL;
+
+	asoc = sctp_id2assoc(sk, param.se_assoc_id);
+	subscribe = asoc ? asoc->subscribe : sctp_sk(sk)->subscribe;
+	param.se_on = sctp_ulpevent_type_enabled(subscribe, param.se_type);
+
+	if (put_user(len, optlen))
+		return -EFAULT;
+
+	if (copy_to_user(optval, &param, len))
+		return -EFAULT;
+
+	return 0;
+}
+
 static int sctp_getsockopt(struct sock *sk, int level, int optname,
 			   char __user *optval, int __user *optlen)
 {
@@ -7607,6 +7713,9 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 	case SCTP_REUSE_PORT:
 		retval = sctp_getsockopt_reuse_port(sk, len, optval, optlen);
 		break;
+	case SCTP_EVENT:
+		retval = sctp_getsockopt_event(sk, len, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;