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>

5 files changed, 42 insertions, 20 deletions

diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index 8dadc74c22e7..4588bdc2b8f0 100644
--- a/include/net/sctp/constants.h
+++ b/include/net/sctp/constants.h
@@ -71,7 +71,7 @@ enum { SCTP_DEFAULT_INSTREAMS = SCTP_MAX_STREAM };
 					 SCTP_NUM_AUTH_CHUNK_TYPES)
 
 /* These are the different flavours of event.  */
-enum sctp_event {
+enum sctp_event_type {
 	SCTP_EVENT_T_CHUNK = 1,
 	SCTP_EVENT_T_TIMEOUT,
 	SCTP_EVENT_T_OTHER,
diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index 9e3d32746430..24825a81829e 100644
--- a/include/net/sctp/sm.h
+++ b/include/net/sctp/sm.h
@@ -173,7 +173,7 @@ sctp_state_fn_t sctp_sf_autoclose_timer_expire;
 __u8 sctp_get_chunk_type(struct sctp_chunk *chunk);
 const struct sctp_sm_table_entry *sctp_sm_lookup_event(
 					struct net *net,
-					enum sctp_event event_type,
+					enum sctp_event_type event_type,
 					enum sctp_state state,
 					union sctp_subtype event_subtype);
 int sctp_chunk_iif(const struct sctp_chunk *);
@@ -313,7 +313,7 @@ struct sctp_chunk *sctp_process_strreset_resp(
 
 /* Prototypes for statetable processing. */
 
-int sctp_do_sm(struct net *net, enum sctp_event event_type,
+int sctp_do_sm(struct net *net, enum sctp_event_type event_type,
 	       union sctp_subtype subtype, enum sctp_state state,
 	       struct sctp_endpoint *ep, struct sctp_association *asoc,
 	       void *event_arg, gfp_t gfp);
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index af9d494120ba..7eaa294d938d 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -217,7 +217,7 @@ struct sctp_sock {
 	 * These two structures must be grouped together for the usercopy
 	 * whitelist region.
 	 */
-	struct sctp_event_subscribe subscribe;
+	__u16 subscribe;
 	struct sctp_initmsg initmsg;
 
 	int user_frag;
@@ -2077,6 +2077,8 @@ struct sctp_association {
 
 	int sent_cnt_removable;
 
+	__u16 subscribe;
+
 	__u64 abandoned_unsent[SCTP_PR_INDEX(MAX) + 1];
 	__u64 abandoned_sent[SCTP_PR_INDEX(MAX) + 1];
 };
diff --git a/include/net/sctp/ulpevent.h b/include/net/sctp/ulpevent.h
index 51b4e0626c34..bd922a0fe914 100644
--- a/include/net/sctp/ulpevent.h
+++ b/include/net/sctp/ulpevent.h
@@ -164,30 +164,39 @@ void sctp_ulpevent_read_nxtinfo(const struct sctp_ulpevent *event,
 
 __u16 sctp_ulpevent_get_notification_type(const struct sctp_ulpevent *event);
 
+static inline void sctp_ulpevent_type_set(__u16 *subscribe,
+					  __u16 sn_type, __u8 on)
+{
+	if (sn_type > SCTP_SN_TYPE_MAX)
+		return;
+
+	if (on)
+		*subscribe |=  (1 << (sn_type - SCTP_SN_TYPE_BASE));
+	else
+		*subscribe &= ~(1 << (sn_type - SCTP_SN_TYPE_BASE));
+}
+
 /* Is this event type enabled? */
-static inline int sctp_ulpevent_type_enabled(__u16 sn_type,
-					     struct sctp_event_subscribe *mask)
+static inline bool sctp_ulpevent_type_enabled(__u16 subscribe, __u16 sn_type)
 {
-	int offset = sn_type - SCTP_SN_TYPE_BASE;
-	char *amask = (char *) mask;
+	if (sn_type > SCTP_SN_TYPE_MAX)
+		return false;
 
-	if (offset >= sizeof(struct sctp_event_subscribe))
-		return 0;
-	return amask[offset];
+	return subscribe & (1 << (sn_type - SCTP_SN_TYPE_BASE));
 }
 
 /* Given an event subscription, is this event enabled? */
-static inline int sctp_ulpevent_is_enabled(const struct sctp_ulpevent *event,
-					   struct sctp_event_subscribe *mask)
+static inline bool sctp_ulpevent_is_enabled(const struct sctp_ulpevent *event,
+					    __u16 subscribe)
 {
 	__u16 sn_type;
-	int enabled = 1;
 
-	if (sctp_ulpevent_is_notification(event)) {
-		sn_type = sctp_ulpevent_get_notification_type(event);
-		enabled = sctp_ulpevent_type_enabled(sn_type, mask);
-	}
-	return enabled;
+	if (!sctp_ulpevent_is_notification(event))
+		return true;
+
+	sn_type = sctp_ulpevent_get_notification_type(event);
+
+	return sctp_ulpevent_type_enabled(subscribe, sn_type);
 }
 
 #endif /* __sctp_ulpevent_h__ */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index c81feb373d3e..d584073532b8 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -129,6 +129,7 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_STREAM_SCHEDULER_VALUE	124
 #define SCTP_INTERLEAVING_SUPPORTED	125
 #define SCTP_SENDMSG_CONNECT	126
+#define SCTP_EVENT	127
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
@@ -632,7 +633,9 @@ union sctp_notification {
  */
 
 enum sctp_sn_type {
-	SCTP_SN_TYPE_BASE     = (1<<15),
+	SCTP_SN_TYPE_BASE	= (1<<15),
+	SCTP_DATA_IO_EVENT	= SCTP_SN_TYPE_BASE,
+#define SCTP_DATA_IO_EVENT		SCTP_DATA_IO_EVENT
 	SCTP_ASSOC_CHANGE,
 #define SCTP_ASSOC_CHANGE		SCTP_ASSOC_CHANGE
 	SCTP_PEER_ADDR_CHANGE,
@@ -657,6 +660,8 @@ enum sctp_sn_type {
 #define SCTP_ASSOC_RESET_EVENT		SCTP_ASSOC_RESET_EVENT
 	SCTP_STREAM_CHANGE_EVENT,
 #define SCTP_STREAM_CHANGE_EVENT	SCTP_STREAM_CHANGE_EVENT
+	SCTP_SN_TYPE_MAX	= SCTP_STREAM_CHANGE_EVENT,
+#define SCTP_SN_TYPE_MAX		SCTP_SN_TYPE_MAX
 };
 
 /* Notification error codes used to fill up the error fields in some
@@ -1150,6 +1155,12 @@ struct sctp_add_streams {
 	uint16_t sas_outstrms;
 };
 
+struct sctp_event {
+	sctp_assoc_t se_assoc_id;
+	uint16_t se_type;
+	uint8_t se_on;
+};
+
 /* SCTP Stream schedulers */
 enum sctp_sched_type {
 	SCTP_SS_FCFS,