Merge branch 'sctp-sender-side-stream-reconf-ssn-reset-request-chunk'

Xin Long says:

====================
sctp: add sender-side procedures for stream reconf ssn reset request chunk

Patch 6/6 is to implement sender-side procedures for the Outgoing
and Incoming SSN Reset Request Parameter described in rfc6525
section 5.1.2 and 5.1.3

Patches 1-5/6 are ahead of it to define some apis and asoc members
for it.

Note that with this patchset, asoc->reconf_enable has no chance yet to
be set, until the patch "sctp: add get and set sockopt for reconf_enable"
is applied in the future. As we can not just enable it when sctp is not
capable of processing reconf chunk yet.

v1->v2:
  - put these into a smaller group.
  - rename some temporary variables in the codes.
  - rename the titles of the commits and improve some changelogs.
v2->v3:
  - re-split the patchset and make sure it has no dead codes for review.
v3->v4:
  - move sctp_make_reconf() into patch 1/6 to avoid kbuild warning.
  - drop unused struct sctp_strreset_req.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

include/linux/sctp.h

@@ -108,6 +108,7 @@ typedef enum {
 	/* Use hex, as defined in ADDIP sec. 3.1 */
 	SCTP_CID_ASCONF			= 0xC1,
 	SCTP_CID_ASCONF_ACK		= 0x80,
+	SCTP_CID_RECONF			= 0x82,
 } sctp_cid_t; /* enum */
 
 
@@ -199,6 +200,13 @@ typedef enum {
 	SCTP_PARAM_SUCCESS_REPORT	= cpu_to_be16(0xc005),
 	SCTP_PARAM_ADAPTATION_LAYER_IND = cpu_to_be16(0xc006),
 
+	/* RE-CONFIG. Section 4 */
+	SCTP_PARAM_RESET_OUT_REQUEST		= cpu_to_be16(0x000d),
+	SCTP_PARAM_RESET_IN_REQUEST		= cpu_to_be16(0x000e),
+	SCTP_PARAM_RESET_TSN_REQUEST		= cpu_to_be16(0x000f),
+	SCTP_PARAM_RESET_RESPONSE		= cpu_to_be16(0x0010),
+	SCTP_PARAM_RESET_ADD_OUT_STREAMS	= cpu_to_be16(0x0011),
+	SCTP_PARAM_RESET_ADD_IN_STREAMS		= cpu_to_be16(0x0012),
 } sctp_param_t; /* enum */
 
 
@@ -710,4 +718,23 @@ struct sctp_infox {
 	struct sctp_association *asoc;
 };
 
+struct sctp_reconf_chunk {
+	sctp_chunkhdr_t chunk_hdr;
+	__u8 params[0];
+} __packed;
+
+struct sctp_strreset_outreq {
+	sctp_paramhdr_t param_hdr;
+	__u32 request_seq;
+	__u32 response_seq;
+	__u32 send_reset_at_tsn;
+	__u16 list_of_streams[0];
+} __packed;
+
+struct sctp_strreset_inreq {
+	sctp_paramhdr_t param_hdr;
+	__u32 request_seq;
+	__u16 list_of_streams[0];
+} __packed;
+
 #endif /* __LINUX_SCTP_H__ */

include/net/netns/sctp.h

@@ -118,6 +118,9 @@ struct netns_sctp {
 	/* Flag to indicate if PR-SCTP is enabled. */
 	int prsctp_enable;
 
+	/* Flag to indicate if PR-CONFIG is enabled. */
+	int reconf_enable;
+
 	/* Flag to idicate if SCTP-AUTH is enabled */
 	int auth_enable;
 

include/net/sctp/constants.h

@@ -90,6 +90,7 @@ typedef enum {
 	SCTP_EVENT_TIMEOUT_T4_RTO,
 	SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
 	SCTP_EVENT_TIMEOUT_HEARTBEAT,
+	SCTP_EVENT_TIMEOUT_RECONF,
 	SCTP_EVENT_TIMEOUT_SACK,
 	SCTP_EVENT_TIMEOUT_AUTOCLOSE,
 } sctp_event_timeout_t;
@@ -113,9 +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
@@ -191,6 +193,12 @@ void sctp_remaddr_proc_exit(struct net *net);
  */
 int sctp_offload_init(void);
 
+/*
+ * sctp/stream.c
+ */
+int sctp_send_reset_streams(struct sctp_association *asoc,
+			    struct sctp_reset_streams *params);
+
 /*
  * Module global variables
  */

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;
@@ -167,6 +168,7 @@ sctp_state_fn_t sctp_sf_cookie_wait_icmp_abort;
 
 /* Prototypes for timeout event state functions.  */
 sctp_state_fn_t sctp_sf_do_6_3_3_rtx;
+sctp_state_fn_t sctp_sf_send_reconf;
 sctp_state_fn_t sctp_sf_do_6_2_sack;
 sctp_state_fn_t sctp_sf_autoclose_timer_expire;
 
@@ -259,7 +261,10 @@ struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
 				    __u32 new_cum_tsn, size_t nstreams,
 				    struct sctp_fwdtsn_skip *skiplist);
 struct sctp_chunk *sctp_make_auth(const struct sctp_association *asoc);
-
+struct sctp_chunk *sctp_make_strreset_req(
+				const struct sctp_association *asoc,
+				__u16 stream_num, __u16 *stream_list,
+				bool out, bool in);
 void sctp_chunk_assign_tsn(struct sctp_chunk *);
 void sctp_chunk_assign_ssn(struct sctp_chunk *);
 
@@ -275,6 +280,7 @@ int sctp_do_sm(struct net *net, sctp_event_t event_type, sctp_subtype_t subtype,
 /* 2nd level prototypes */
 void sctp_generate_t3_rtx_event(unsigned long peer);
 void sctp_generate_heartbeat_event(unsigned long peer);
+void sctp_generate_reconf_event(unsigned long peer);
 void sctp_generate_proto_unreach_event(unsigned long peer);
 
 void sctp_ootb_pkt_free(struct sctp_packet *);

include/net/sctp/structs.h

@@ -877,6 +877,9 @@ struct sctp_transport {
 	/* Timer to handle ICMP proto unreachable envets */
 	struct timer_list proto_unreach_timer;
 
+	/* Timer to handler reconf chunk rtx */
+	struct timer_list reconf_timer;
+
 	/* Since we're using per-destination retransmission timers
 	 * (see above), we're also using per-destination "transmitted"
 	 * queues.  This probably ought to be a private struct
@@ -935,6 +938,7 @@ void sctp_transport_pmtu(struct sctp_transport *, struct sock *sk);
 void sctp_transport_free(struct sctp_transport *);
 void sctp_transport_reset_t3_rtx(struct sctp_transport *);
 void sctp_transport_reset_hb_timer(struct sctp_transport *);
+void sctp_transport_reset_reconf_timer(struct sctp_transport *transport);
 int sctp_transport_hold(struct sctp_transport *);
 void sctp_transport_put(struct sctp_transport *);
 void sctp_transport_update_rto(struct sctp_transport *, __u32);
@@ -1251,7 +1255,10 @@ struct sctp_endpoint {
 	struct list_head endpoint_shared_keys;
 	__u16 active_key_id;
 	__u8  auth_enable:1,
-	      prsctp_enable:1;
+	      prsctp_enable:1,
+	      reconf_enable:1;
+
+	__u8  strreset_enable;
 };
 
 /* Recover the outter endpoint structure. */
@@ -1504,6 +1511,7 @@ struct sctp_association {
 			hostname_address:1, /* Peer understands DNS addresses? */
 			asconf_capable:1,   /* Does peer support ADDIP? */
 			prsctp_capable:1,   /* Can peer do PR-SCTP? */
+			reconf_capable:1,   /* Can peer do RE-CONFIG? */
 			auth_capable:1;     /* Is peer doing SCTP-AUTH? */
 
 		/* sack_needed : This flag indicates if the next received
@@ -1863,7 +1871,16 @@ struct sctp_association {
 
 	__u8 need_ecne:1,	/* Need to send an ECNE Chunk? */
 	     temp:1,		/* Is it a temporary association? */
-	     prsctp_enable:1;
+	     prsctp_enable:1,
+	     reconf_enable:1;
+
+	__u8 strreset_enable;
+	__u8 strreset_outstanding; /* request param count on the fly */
+
+	__u32 strreset_outseq; /* Update after receiving response */
+	__u32 strreset_inseq; /* Update after receiving request */
+
+	struct sctp_chunk *strreset_chunk; /* save request chunk */
 
 	struct sctp_priv_assoc_stats stats;
 

include/uapi/linux/sctp.h

@@ -115,6 +115,8 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_PR_SUPPORTED	113
 #define SCTP_DEFAULT_PRINFO	114
 #define SCTP_PR_ASSOC_STATUS	115
+#define SCTP_ENABLE_STREAM_RESET	118
+#define SCTP_RESET_STREAMS	119
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
@@ -138,6 +140,15 @@ typedef __s32 sctp_assoc_t;
 #define SCTP_PR_RTX_ENABLED(x)	(SCTP_PR_POLICY(x) == SCTP_PR_SCTP_RTX)
 #define SCTP_PR_PRIO_ENABLED(x)	(SCTP_PR_POLICY(x) == SCTP_PR_SCTP_PRIO)
 
+/* For enable stream reset */
+#define SCTP_ENABLE_RESET_STREAM_REQ	0x01
+#define SCTP_ENABLE_RESET_ASSOC_REQ	0x02
+#define SCTP_ENABLE_CHANGE_ASSOC_REQ	0x04
+#define SCTP_ENABLE_STRRESET_MASK	0x07
+
+#define SCTP_STREAM_RESET_INCOMING	0x01
+#define SCTP_STREAM_RESET_OUTGOING	0x02
+
 /* These are bit fields for msghdr->msg_flags.  See section 5.1.  */
 /* On user space Linux, these live in <bits/socket.h> as an enum.  */
 enum sctp_msg_flags {
@@ -1008,4 +1019,11 @@ struct sctp_info {
 	__u32	__reserved3;
 };
 
+struct sctp_reset_streams {
+	sctp_assoc_t srs_assoc_id;
+	uint16_t srs_flags;
+	uint16_t srs_number_streams;	/* 0 == ALL */
+	uint16_t srs_stream_list[];	/* list if srs_num_streams is not 0 */
+};
+
 #endif /* _UAPI_SCTP_H */

net/sctp/associola.c

@@ -207,6 +207,7 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
 	 * association to the same value as the initial TSN.
 	 */
 	asoc->addip_serial = asoc->c.initial_tsn;
+	asoc->strreset_outseq = asoc->c.initial_tsn;
 
 	INIT_LIST_HEAD(&asoc->addip_chunk_list);
 	INIT_LIST_HEAD(&asoc->asconf_ack_list);
@@ -269,6 +270,8 @@ static struct sctp_association *sctp_association_init(struct sctp_association *a
 
 	asoc->active_key_id = ep->active_key_id;
 	asoc->prsctp_enable = ep->prsctp_enable;
+	asoc->reconf_enable = ep->reconf_enable;
+	asoc->strreset_enable = ep->strreset_enable;
 
 	/* Save the hmacs and chunks list into this association */
 	if (ep->auth_hmacs_list)
@@ -361,6 +364,9 @@ void sctp_association_free(struct sctp_association *asoc)
 	/* Free stream information. */
 	sctp_stream_free(asoc->stream);
 
+	if (asoc->strreset_chunk)
+		sctp_chunk_free(asoc->strreset_chunk);
+
 	/* Clean up the bound address list. */
 	sctp_bind_addr_free(&asoc->base.bind_addr);
 
@@ -519,6 +525,12 @@ void sctp_assoc_rm_peer(struct sctp_association *asoc,
 	if (asoc->peer.last_data_from == peer)
 		asoc->peer.last_data_from = transport;
 
+	if (asoc->strreset_chunk &&
+	    asoc->strreset_chunk->transport == peer) {
+		asoc->strreset_chunk->transport = transport;
+		sctp_transport_reset_reconf_timer(transport);
+	}
+
 	/* If we remove the transport an INIT was last sent to, set it to
 	 * NULL. Combined with the update of the retran path above, this
 	 * will cause the next INIT to be sent to the next available

net/sctp/endpointola.c

@@ -164,6 +164,7 @@ static struct sctp_endpoint *sctp_endpoint_init(struct sctp_endpoint *ep,
 	ep->auth_hmacs_list = auth_hmacs;
 	ep->auth_chunk_list = auth_chunks;
 	ep->prsctp_enable = net->sctp.prsctp_enable;
+	ep->reconf_enable = net->sctp.reconf_enable;
 
 	return ep;
 

net/sctp/outqueue.c

@@ -915,22 +915,28 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
 		case SCTP_CID_ECN_ECNE:
 		case SCTP_CID_ASCONF:
 		case SCTP_CID_FWD_TSN:
+		case SCTP_CID_RECONF:
 			status = sctp_packet_transmit_chunk(packet, chunk,
 							    one_packet, gfp);
 			if (status  != SCTP_XMIT_OK) {
 				/* put the chunk back */
 				list_add(&chunk->list, &q->control_chunk_list);
-			} else {
-				asoc->stats.octrlchunks++;
-				/* PR-SCTP C5) If a FORWARD TSN is sent, the
-				 * sender MUST assure that at least one T3-rtx
-				 * timer is running.
-				 */
-				if (chunk->chunk_hdr->type == SCTP_CID_FWD_TSN) {
-					sctp_transport_reset_t3_rtx(transport);
-					transport->last_time_sent = jiffies;
-				}
+				break;
+			}
+
+			asoc->stats.octrlchunks++;
+			/* PR-SCTP C5) If a FORWARD TSN is sent, the
+			 * sender MUST assure that at least one T3-rtx
+			 * timer is running.
+			 */
+			if (chunk->chunk_hdr->type == SCTP_CID_FWD_TSN) {
+				sctp_transport_reset_t3_rtx(transport);
+				transport->last_time_sent = jiffies;
 			}
+
+			if (chunk == asoc->strreset_chunk)
+				sctp_transport_reset_reconf_timer(transport);
+
 			break;
 
 		default:
@@ -1016,6 +1022,8 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
 
 		/* Finally, transmit new packets.  */
 		while ((chunk = sctp_outq_dequeue_data(q)) != NULL) {
+			__u32 sid = ntohs(chunk->subh.data_hdr->stream);
+
 			/* RFC 2960 6.5 Every DATA chunk MUST carry a valid
 			 * stream identifier.
 			 */
@@ -1038,6 +1046,11 @@ static void sctp_outq_flush(struct sctp_outq *q, int rtx_timeout, gfp_t gfp)
 				continue;
 			}
 
+			if (asoc->stream->out[sid].state == SCTP_STREAM_CLOSED) {
+				sctp_outq_head_data(q, chunk);
+				goto sctp_flush_out;
+			}
+
 			/* If there is a specified transport, use it.
 			 * Otherwise, we want to use the active path.
 			 */

net/sctp/primitive.c

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

net/sctp/protocol.c

@@ -1258,6 +1258,9 @@ static int __net_init sctp_defaults_init(struct net *net)
 	/* Enable PR-SCTP by default. */
 	net->sctp.prsctp_enable = 1;
 
+	/* Disable RECONF by default. */
+	net->sctp.reconf_enable = 0;
+
 	/* Disable AUTH by default. */
 	net->sctp.auth_enable = 0;