[PATCHv4 net-next 0/6] sctp: add sender-side procedures for stream reconf ssn reset request chunk

[PATCHv4 net-next 0/6] sctp: add sender-side procedures for stream reconf ssn reset request chunk

[Xin Long]

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.

Xin Long (6):
  sctp: add support for generating stream reconf ssn reset request chunk
  sctp: add stream reconf timer
  sctp: add stream reconf primitive
  sctp: add reconf_enable in asoc ep and netns
  sctp: add sockopt SCTP_ENABLE_STREAM_RESET
  sctp: implement sender-side procedures for SSN Reset Request Parameter

 include/linux/sctp.h         |  27 +++++++++
 include/net/netns/sctp.h     |   3 +
 include/net/sctp/constants.h |   4 +-
 include/net/sctp/sctp.h      |   8 +++
 include/net/sctp/sm.h        |   8 ++-
 include/net/sctp/structs.h   |  21 ++++++-
 include/uapi/linux/sctp.h    |  18 ++++++
 net/sctp/associola.c         |  12 ++++
 net/sctp/endpointola.c       |   1 +
 net/sctp/outqueue.c          |  33 +++++++----
 net/sctp/primitive.c         |   3 +
 net/sctp/protocol.c          |   3 +
 net/sctp/sm_make_chunk.c     | 136 +++++++++++++++++++++++++++++++++++++++++++
 net/sctp/sm_sideeffect.c     |  32 ++++++++++
 net/sctp/sm_statefuns.c      |  41 +++++++++++++
 net/sctp/sm_statetable.c     |  40 +++++++++++++
 net/sctp/socket.c            | 113 +++++++++++++++++++++++++++++++++++
 net/sctp/stream.c            |  79 +++++++++++++++++++++++++
 net/sctp/transport.c         |  17 +++++-
 19 files changed, 583 insertions(+), 16 deletions(-)

-- 
2.1.0

[PATCHv4 net-next 1/6] sctp: add support for generating stream reconf ssn reset request chunk

[Xin Long]

This patch is to add asoc strreset_outseq and strreset_inseq for
saving the reconf request sequence, initialize them when create
assoc and process init, and also to define Incoming and Outgoing
SSN Reset Request Parameter described in rfc6525 section 4.1 and
4.2, As they can be in one same chunk as section rfc6525 3.1-3
describes, it makes them in one function.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/linux/sctp.h       |  27 ++++++++++
 include/net/sctp/sm.h      |   5 +-
 include/net/sctp/structs.h |   3 ++
 net/sctp/associola.c       |   1 +
 net/sctp/sm_make_chunk.c   | 121 +++++++++++++++++++++++++++++++++++++++++++++
 5 files changed, 156 insertions(+), 1 deletion(-)

diff --git a/include/linux/sctp.h b/include/linux/sctp.h
index fcb4c36..a9e7906 100644
--- a/include/linux/sctp.h
+++ b/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__ */
diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index ca6c971..3462cb0 100644
--- a/include/net/sctp/sm.h
+++ b/include/net/sctp/sm.h
@@ -259,7 +259,10 @@ 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 *);
 
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 4741ec2..3dc983e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1865,6 +1865,9 @@ struct sctp_association {
 	     temp:1,		/* Is it a temporary association? */
 	     prsctp_enable:1;
 
+	__u32 strreset_outseq; /* Update after receiving response */
+	__u32 strreset_inseq; /* Update after receiving request */
+
 	struct sctp_priv_assoc_stats stats;
 
 	int sent_cnt_removable;
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 36294f7..42ece6f 100644
--- a/net/sctp/associola.c
+++ b/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);
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index a15d824..172385c 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -1844,6 +1844,7 @@ struct sctp_association *sctp_unpack_cookie(
 	retval->next_tsn = retval->c.initial_tsn;
 	retval->ctsn_ack_point = retval->next_tsn - 1;
 	retval->addip_serial = retval->c.initial_tsn;
+	retval->strreset_outseq = retval->c.initial_tsn;
 	retval->adv_peer_ack_point = retval->ctsn_ack_point;
 	retval->peer.prsctp_capable = retval->c.prsctp_capable;
 	retval->peer.adaptation_ind = retval->c.adaptation_ind;
@@ -2387,6 +2388,8 @@ int sctp_process_init(struct sctp_association *asoc, struct sctp_chunk *chunk,
 	asoc->peer.i.initial_tsn  		ntohl(peer_init->init_hdr.initial_tsn);
 
+	asoc->strreset_inseq = asoc->peer.i.initial_tsn;
+
 	/* Apply the upper bounds for output streams based on peer's
 	 * number of inbound streams.
 	 */
@@ -3526,3 +3529,121 @@ struct sctp_chunk *sctp_make_fwdtsn(const struct sctp_association *asoc,
 
 	return retval;
 }
+
+/* RE-CONFIG 3.1 (RE-CONFIG chunk)
+ *   0                   1                   2                   3
+ *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  | Type = 130    |  Chunk Flags  |      Chunk Length             |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  \                                                               \
+ *  /                  Re-configuration Parameter                   /
+ *  \                                                               \
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  \                                                               \
+ *  /             Re-configuration Parameter (optional)             /
+ *  \                                                               \
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+static struct sctp_chunk *sctp_make_reconf(
+				const struct sctp_association *asoc,
+				int length)
+{
+	struct sctp_reconf_chunk *reconf;
+	struct sctp_chunk *retval;
+
+	retval = sctp_make_control(asoc, SCTP_CID_RECONF, 0, length,
+				   GFP_ATOMIC);
+	if (!retval)
+		return NULL;
+
+	reconf = (struct sctp_reconf_chunk *)retval->chunk_hdr;
+	retval->param_hdr.v = reconf->params;
+
+	return retval;
+}
+
+/* RE-CONFIG 4.1 (STREAM OUT RESET)
+ *   0                   1                   2                   3
+ *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |     Parameter Type = 13       | Parameter Length = 16 + 2 * N |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |           Re-configuration Request Sequence Number            |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |           Re-configuration Response Sequence Number           |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |                Sender's Last Assigned TSN                     |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |  Stream Number 1 (optional)   |    Stream Number 2 (optional) |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  /                            ......                             /
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |  Stream Number N-1 (optional) |    Stream Number N (optional) |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *
+ * RE-CONFIG 4.2 (STREAM IN RESET)
+ *   0                   1                   2                   3
+ *   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |     Parameter Type = 14       |  Parameter Length = 8 + 2 * N |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |          Re-configuration Request Sequence Number             |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |  Stream Number 1 (optional)   |    Stream Number 2 (optional) |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  /                            ......                             /
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ *  |  Stream Number N-1 (optional) |    Stream Number N (optional) |
+ *  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
+ */
+struct sctp_chunk *sctp_make_strreset_req(
+				const struct sctp_association *asoc,
+				__u16 stream_num, __u16 *stream_list,
+				bool out, bool in)
+{
+	struct sctp_strreset_outreq outreq;
+	__u16 stream_len = stream_num * 2;
+	struct sctp_strreset_inreq inreq;
+	struct sctp_chunk *retval;
+	__u16 outlen, inlen, i;
+
+	outlen = (sizeof(outreq) + stream_len) * out;
+	inlen = (sizeof(inreq) + stream_len) * in;
+
+	retval = sctp_make_reconf(asoc, outlen + inlen);
+	if (!retval)
+		return NULL;
+
+	for (i = 0; i < stream_num; i++)
+		stream_list[i] = htons(stream_list[i]);
+
+	if (outlen) {
+		outreq.param_hdr.type = SCTP_PARAM_RESET_OUT_REQUEST;
+		outreq.param_hdr.length = htons(outlen);
+		outreq.request_seq = htonl(asoc->strreset_outseq);
+		outreq.response_seq = htonl(asoc->strreset_inseq - 1);
+		outreq.send_reset_at_tsn = htonl(asoc->next_tsn - 1);
+
+		sctp_addto_chunk(retval, sizeof(outreq), &outreq);
+
+		if (stream_len)
+			sctp_addto_chunk(retval, stream_len, stream_list);
+	}
+
+	if (inlen) {
+		inreq.param_hdr.type = SCTP_PARAM_RESET_IN_REQUEST;
+		inreq.param_hdr.length = htons(inlen);
+		inreq.request_seq = htonl(asoc->strreset_outseq + out);
+
+		sctp_addto_chunk(retval, sizeof(inreq), &inreq);
+
+		if (stream_len)
+			sctp_addto_chunk(retval, stream_len, stream_list);
+	}
+
+	for (i = 0; i < stream_num; i++)
+		stream_list[i] = ntohs(stream_list[i]);
+
+	return retval;
+}
-- 
2.1.0

[PATCHv4 net-next 2/6] sctp: add stream reconf timer

[Xin Long]

This patch is to add a per transport timer based on sctp timer frame
for stream reconf chunk retransmission. It would start after sending
a reconf request chunk, and stop after receiving the response chunk.

If the timer expires, besides retransmitting the reconf request chunk,
it would also do the same thing with data RTO timer. like to increase
the appropriate error counts, and perform threshold management, possibly
destroying the asoc if sctp retransmission thresholds are exceeded, just
as section 5.1.1 describes.

This patch is also to add asoc strreset_chunk, it is used to save the
reconf request chunk, so that it can be retransmitted, and to check if
the response is really for this request by comparing the information
inside with the response chunk as well.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/sctp/constants.h |  1 +
 include/net/sctp/sm.h        |  2 ++
 include/net/sctp/structs.h   |  6 ++++++
 net/sctp/associola.c         |  9 +++++++++
 net/sctp/sm_sideeffect.c     | 32 ++++++++++++++++++++++++++++++++
 net/sctp/sm_statefuns.c      | 28 ++++++++++++++++++++++++++++
 net/sctp/sm_statetable.c     | 20 ++++++++++++++++++++
 net/sctp/transport.c         | 17 +++++++++++++++--
 8 files changed, 113 insertions(+), 2 deletions(-)

diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index 5b847e4..8307c86 100644
--- a/include/net/sctp/constants.h
+++ b/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;
diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index 3462cb0..d2d9e28 100644
--- a/include/net/sctp/sm.h
+++ b/include/net/sctp/sm.h
@@ -167,6 +167,7 @@ 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;
 
@@ -278,6 +279,7 @@ 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 *);
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 3dc983e..463b4d6 100644
--- a/include/net/sctp/structs.h
+++ b/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);
@@ -1868,6 +1872,8 @@ struct sctp_association {
 	__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;
 
 	int sent_cnt_removable;
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 42ece6f..fc33540 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -362,6 +362,9 @@ 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);
 
@@ -520,6 +523,12 @@ 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
diff --git a/net/sctp/sm_sideeffect.c b/net/sctp/sm_sideeffect.c
index c345bf1..a455271 100644
--- a/net/sctp/sm_sideeffect.c
+++ b/net/sctp/sm_sideeffect.c
@@ -436,6 +436,37 @@ void sctp_generate_proto_unreach_event(unsigned long data)
 	sctp_association_put(asoc);
 }
 
+ /* Handle the timeout of the RE-CONFIG timer. */
+void sctp_generate_reconf_event(unsigned long data)
+{
+	struct sctp_transport *transport = (struct sctp_transport *)data;
+	struct sctp_association *asoc = transport->asoc;
+	struct sock *sk = asoc->base.sk;
+	struct net *net = sock_net(sk);
+	int error = 0;
+
+	bh_lock_sock(sk);
+	if (sock_owned_by_user(sk)) {
+		pr_debug("%s: sock is busy\n", __func__);
+
+		/* Try again later.  */
+		if (!mod_timer(&transport->reconf_timer, jiffies + (HZ / 20)))
+			sctp_transport_hold(transport);
+		goto out_unlock;
+	}
+
+	error = sctp_do_sm(net, SCTP_EVENT_T_TIMEOUT,
+			   SCTP_ST_TIMEOUT(SCTP_EVENT_TIMEOUT_RECONF),
+			   asoc->state, asoc->ep, asoc,
+			   transport, GFP_ATOMIC);
+
+	if (error)
+		sk->sk_err = -error;
+
+out_unlock:
+	bh_unlock_sock(sk);
+	sctp_transport_put(transport);
+}
 
 /* Inject a SACK Timeout event into the state machine.  */
 static void sctp_generate_sack_event(unsigned long data)
@@ -453,6 +484,7 @@ sctp_timer_event_t *sctp_timer_events[SCTP_NUM_TIMEOUT_TYPES] = {
 	sctp_generate_t4_rto_event,
 	sctp_generate_t5_shutdown_guard_event,
 	NULL,
+	NULL,
 	sctp_generate_sack_event,
 	sctp_generate_autoclose_event,
 };
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 0ceded3..2ae186a 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -1021,6 +1021,34 @@ sctp_disposition_t sctp_sf_sendbeat_8_3(struct net *net,
 	return SCTP_DISPOSITION_CONSUME;
 }
 
+/* resend asoc strreset_chunk.  */
+sctp_disposition_t sctp_sf_send_reconf(struct net *net,
+				       const struct sctp_endpoint *ep,
+				       const struct sctp_association *asoc,
+				       const sctp_subtype_t type, void *arg,
+				       sctp_cmd_seq_t *commands)
+{
+	struct sctp_transport *transport = arg;
+
+	if (asoc->overall_error_count >= asoc->max_retrans) {
+		sctp_add_cmd_sf(commands, SCTP_CMD_SET_SK_ERR,
+				SCTP_ERROR(ETIMEDOUT));
+		/* CMD_ASSOC_FAILED calls CMD_DELETE_TCB. */
+		sctp_add_cmd_sf(commands, SCTP_CMD_ASSOC_FAILED,
+				SCTP_PERR(SCTP_ERROR_NO_ERROR));
+		SCTP_INC_STATS(net, SCTP_MIB_ABORTEDS);
+		SCTP_DEC_STATS(net, SCTP_MIB_CURRESTAB);
+		return SCTP_DISPOSITION_DELETE_TCB;
+	}
+
+	sctp_chunk_hold(asoc->strreset_chunk);
+	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY,
+			SCTP_CHUNK(asoc->strreset_chunk));
+	sctp_add_cmd_sf(commands, SCTP_CMD_STRIKE, SCTP_TRANSPORT(transport));
+
+	return SCTP_DISPOSITION_CONSUME;
+}
+
 /*
  * Process an heartbeat request.
  *
diff --git a/net/sctp/sm_statetable.c b/net/sctp/sm_statetable.c
index a987d54..3da521a 100644
--- a/net/sctp/sm_statetable.c
+++ b/net/sctp/sm_statetable.c
@@ -888,6 +888,25 @@ static const sctp_sm_table_entry_t other_event_table[SCTP_NUM_OTHER_TYPES][SCTP_
 	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
 }
 
+#define TYPE_SCTP_EVENT_TIMEOUT_RECONF { \
+	/* SCTP_STATE_CLOSED */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_COOKIE_WAIT */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_COOKIE_ECHOED */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_ESTABLISHED */ \
+	TYPE_SCTP_FUNC(sctp_sf_send_reconf), \
+	/* SCTP_STATE_SHUTDOWN_PENDING */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_SHUTDOWN_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_SHUTDOWN_RECEIVED */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+	/* SCTP_STATE_SHUTDOWN_ACK_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_timer_ignore), \
+}
+
 static const sctp_sm_table_entry_t timeout_event_table[SCTP_NUM_TIMEOUT_TYPES][SCTP_STATE_NUM_STATES] = {
 	TYPE_SCTP_EVENT_TIMEOUT_NONE,
 	TYPE_SCTP_EVENT_TIMEOUT_T1_COOKIE,
@@ -897,6 +916,7 @@ static const sctp_sm_table_entry_t timeout_event_table[SCTP_NUM_TIMEOUT_TYPES][S
 	TYPE_SCTP_EVENT_TIMEOUT_T4_RTO,
 	TYPE_SCTP_EVENT_TIMEOUT_T5_SHUTDOWN_GUARD,
 	TYPE_SCTP_EVENT_TIMEOUT_HEARTBEAT,
+	TYPE_SCTP_EVENT_TIMEOUT_RECONF,
 	TYPE_SCTP_EVENT_TIMEOUT_SACK,
 	TYPE_SCTP_EVENT_TIMEOUT_AUTOCLOSE,
 };
diff --git a/net/sctp/transport.c b/net/sctp/transport.c
index a1652ab..baa1ac0 100644
--- a/net/sctp/transport.c
+++ b/net/sctp/transport.c
@@ -88,9 +88,11 @@ static struct sctp_transport *sctp_transport_init(struct net *net,
 	INIT_LIST_HEAD(&peer->transports);
 
 	setup_timer(&peer->T3_rtx_timer, sctp_generate_t3_rtx_event,
-			(unsigned long)peer);
+		    (unsigned long)peer);
 	setup_timer(&peer->hb_timer, sctp_generate_heartbeat_event,
-			(unsigned long)peer);
+		    (unsigned long)peer);
+	setup_timer(&peer->reconf_timer, sctp_generate_reconf_event,
+		    (unsigned long)peer);
 	setup_timer(&peer->proto_unreach_timer,
 		    sctp_generate_proto_unreach_event, (unsigned long)peer);
 
@@ -144,6 +146,9 @@ void sctp_transport_free(struct sctp_transport *transport)
 	if (del_timer(&transport->T3_rtx_timer))
 		sctp_transport_put(transport);
 
+	if (del_timer(&transport->reconf_timer))
+		sctp_transport_put(transport);
+
 	/* Delete the ICMP proto unreachable timer if it's active. */
 	if (del_timer(&transport->proto_unreach_timer))
 		sctp_association_put(transport->asoc);
@@ -211,6 +216,14 @@ void sctp_transport_reset_hb_timer(struct sctp_transport *transport)
 		sctp_transport_hold(transport);
 }
 
+void sctp_transport_reset_reconf_timer(struct sctp_transport *transport)
+{
+	if (!timer_pending(&transport->reconf_timer))
+		if (!mod_timer(&transport->reconf_timer,
+			       jiffies + transport->rto))
+			sctp_transport_hold(transport);
+}
+
 /* This transport has been assigned to an association.
  * Initialize fields from the association or from the sock itself.
  * Register the reference count in the association.
-- 
2.1.0

[PATCHv4 net-next 3/6] sctp: add stream reconf primitive

[Xin Long]

This patch is to add a primitive based on sctp primitive frame for
sending stream reconf request. It works as the other primitives,
and create a SCTP_CMD_REPLY command to send the request chunk out.

sctp_primitive_RECONF would be the api to send a reconf request
chunk.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/sctp/constants.h |  3 ++-
 include/net/sctp/sctp.h      |  2 ++
 include/net/sctp/sm.h        |  1 +
 net/sctp/primitive.c         |  3 +++
 net/sctp/sm_statefuns.c      | 13 +++++++++++++
 net/sctp/sm_statetable.c     | 20 ++++++++++++++++++++
 6 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/include/net/sctp/constants.h b/include/net/sctp/constants.h
index 8307c86..3567c97 100644
--- a/include/net/sctp/constants.h
+++ b/include/net/sctp/constants.h
@@ -114,9 +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.
diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index 598d938..bc0e049 100644
--- a/include/net/sctp/sctp.h
+++ b/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
diff --git a/include/net/sctp/sm.h b/include/net/sctp/sm.h
index d2d9e28..430ed13 100644
--- a/include/net/sctp/sm.h
+++ b/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;
diff --git a/net/sctp/primitive.c b/net/sctp/primitive.c
index ab8d9f9..f0553a0 100644
--- a/net/sctp/primitive.c
+++ b/net/sctp/primitive.c
@@ -211,3 +211,6 @@ DECLARE_PRIMITIVE(REQUESTHEARTBEAT);
 */
 
 DECLARE_PRIMITIVE(ASCONF);
+
+/* RE-CONFIG 5.1 */
+DECLARE_PRIMITIVE(RECONF);
diff --git a/net/sctp/sm_statefuns.c b/net/sctp/sm_statefuns.c
index 2ae186a..782e579 100644
--- a/net/sctp/sm_statefuns.c
+++ b/net/sctp/sm_statefuns.c
@@ -5185,6 +5185,19 @@ sctp_disposition_t sctp_sf_do_prm_asconf(struct net *net,
 	return SCTP_DISPOSITION_CONSUME;
 }
 
+/* RE-CONFIG Section 5.1 RECONF Chunk Procedures */
+sctp_disposition_t sctp_sf_do_prm_reconf(struct net *net,
+					 const struct sctp_endpoint *ep,
+					 const struct sctp_association *asoc,
+					 const sctp_subtype_t type,
+					 void *arg, sctp_cmd_seq_t *commands)
+{
+	struct sctp_chunk *chunk = arg;
+
+	sctp_add_cmd_sf(commands, SCTP_CMD_REPLY, SCTP_CHUNK(chunk));
+	return SCTP_DISPOSITION_CONSUME;
+}
+
 /*
  * Ignore the primitive event
  *
diff --git a/net/sctp/sm_statetable.c b/net/sctp/sm_statetable.c
index 3da521a..b5438b4 100644
--- a/net/sctp/sm_statetable.c
+++ b/net/sctp/sm_statetable.c
@@ -643,6 +643,25 @@ chunk_event_table_unknown[SCTP_STATE_NUM_STATES] = {
 	TYPE_SCTP_FUNC(sctp_sf_error_shutdown), \
 } /* TYPE_SCTP_PRIMITIVE_ASCONF */
 
+#define TYPE_SCTP_PRIMITIVE_RECONF { \
+	/* SCTP_STATE_CLOSED */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_COOKIE_WAIT */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_COOKIE_ECHOED */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_closed), \
+	/* SCTP_STATE_ESTABLISHED */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_PENDING */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_RECEIVED */ \
+	TYPE_SCTP_FUNC(sctp_sf_do_prm_reconf), \
+	/* SCTP_STATE_SHUTDOWN_ACK_SENT */ \
+	TYPE_SCTP_FUNC(sctp_sf_error_shutdown), \
+} /* TYPE_SCTP_PRIMITIVE_RECONF */
+
 /* The primary index for this table is the primitive type.
  * The secondary index for this table is the state.
  */
@@ -653,6 +672,7 @@ static const sctp_sm_table_entry_t primitive_event_table[SCTP_NUM_PRIMITIVE_TYPE
 	TYPE_SCTP_PRIMITIVE_SEND,
 	TYPE_SCTP_PRIMITIVE_REQUESTHEARTBEAT,
 	TYPE_SCTP_PRIMITIVE_ASCONF,
+	TYPE_SCTP_PRIMITIVE_RECONF,
 };
 
 #define TYPE_SCTP_OTHER_NO_PENDING_TSN  { \
-- 
2.1.0

[PATCHv4 net-next 4/6] sctp: add reconf_enable in asoc ep and netns

[Xin Long]

This patch is to add reconf_enable field in all of asoc ep and netns
to indicate if they support stream reset.

When initializing, asoc reconf_enable get the default value from ep
reconf_enable which is from netns netns reconf_enable by default.

It is also to add reconf_capable in asoc peer part to know if peer
supports reconf_enable, the value is set if ext params have reconf
chunk support when processing init chunk, just as rfc6525 section
5.1.1 demands.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/netns/sctp.h   |  3 +++
 include/net/sctp/structs.h |  7 +++++--
 net/sctp/associola.c       |  1 +
 net/sctp/endpointola.c     |  1 +
 net/sctp/protocol.c        |  3 +++
 net/sctp/sm_make_chunk.c   | 15 +++++++++++++++
 6 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/include/net/netns/sctp.h b/include/net/netns/sctp.h
index c501d67..b7871d0 100644
--- a/include/net/netns/sctp.h
+++ b/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;
 
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 463b4d6..ee037ef 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1255,7 +1255,8 @@ 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;
 };
 
 /* Recover the outter endpoint structure. */
@@ -1508,6 +1509,7 @@ 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
@@ -1867,7 +1869,8 @@ 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;
 
 	__u32 strreset_outseq; /* Update after receiving response */
 	__u32 strreset_inseq; /* Update after receiving request */
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index fc33540..68b99ad 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -270,6 +270,7 @@ 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;
 
 	/* Save the hmacs and chunks list into this association */
 	if (ep->auth_hmacs_list)
diff --git a/net/sctp/endpointola.c b/net/sctp/endpointola.c
index 410ddc1..8c58923 100644
--- a/net/sctp/endpointola.c
+++ b/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;
 
diff --git a/net/sctp/protocol.c b/net/sctp/protocol.c
index f9c3c37..8227bbb 100644
--- a/net/sctp/protocol.c
+++ b/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;
 
diff --git a/net/sctp/sm_make_chunk.c b/net/sctp/sm_make_chunk.c
index 172385c..c4a0a9c 100644
--- a/net/sctp/sm_make_chunk.c
+++ b/net/sctp/sm_make_chunk.c
@@ -270,6 +270,11 @@ struct sctp_chunk *sctp_make_init(const struct sctp_association *asoc,
 		num_ext += 2;
 	}
 
+	if (asoc->reconf_enable) {
+		extensions[num_ext] = SCTP_CID_RECONF;
+		num_ext += 1;
+	}
+
 	if (sp->adaptation_ind)
 		chunksize += sizeof(aiparam);
 
@@ -434,6 +439,11 @@ struct sctp_chunk *sctp_make_init_ack(const struct sctp_association *asoc,
 		num_ext += 2;
 	}
 
+	if (asoc->peer.reconf_capable) {
+		extensions[num_ext] = SCTP_CID_RECONF;
+		num_ext += 1;
+	}
+
 	if (sp->adaptation_ind)
 		chunksize += sizeof(aiparam);
 
@@ -2012,6 +2022,11 @@ static void sctp_process_ext_param(struct sctp_association *asoc,
 
 	for (i = 0; i < num_ext; i++) {
 		switch (param.ext->chunks[i]) {
+		case SCTP_CID_RECONF:
+			if (asoc->reconf_enable &&
+			    !asoc->peer.reconf_capable)
+				asoc->peer.reconf_capable = 1;
+			break;
 		case SCTP_CID_FWD_TSN:
 			if (asoc->prsctp_enable && !asoc->peer.prsctp_capable)
 				asoc->peer.prsctp_capable = 1;
-- 
2.1.0

[PATCHv4 net-next 5/6] sctp: add sockopt SCTP_ENABLE_STREAM_RESET

[Xin Long]

This patch is to add sockopt SCTP_ENABLE_STREAM_RESET to get/set
strreset_enable to indicate which reconf request type it supports,
which is described in rfc6525 section 6.3.1.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/sctp/structs.h |  4 +++
 include/uapi/linux/sctp.h  |  7 ++++
 net/sctp/associola.c       |  1 +
 net/sctp/socket.c          | 84 ++++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 96 insertions(+)

diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index ee037ef..d99b76e 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1257,6 +1257,8 @@ struct sctp_endpoint {
 	__u8  auth_enable:1,
 	      prsctp_enable:1,
 	      reconf_enable:1;
+
+	__u8  strreset_enable;
 };
 
 /* Recover the outter endpoint structure. */
@@ -1872,6 +1874,8 @@ struct sctp_association {
 	     prsctp_enable:1,
 	     reconf_enable:1;
 
+	__u8 strreset_enable;
+
 	__u32 strreset_outseq; /* Update after receiving response */
 	__u32 strreset_inseq; /* Update after receiving request */
 
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index a406adc..867be0f 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -115,6 +115,7 @@ 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
 
 /* PR-SCTP policies */
 #define SCTP_PR_SCTP_NONE	0x0000
@@ -138,6 +139,12 @@ 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
+
 /* 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 {
diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index 68b99ad..e50dc6d 100644
--- a/net/sctp/associola.c
+++ b/net/sctp/associola.c
@@ -271,6 +271,7 @@ 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)
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index 318c678..ae07db4 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3751,6 +3751,42 @@ static int sctp_setsockopt_default_prinfo(struct sock *sk,
 	return retval;
 }
 
+static int sctp_setsockopt_enable_strreset(struct sock *sk,
+					   char __user *optval,
+					   unsigned int optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen != sizeof(params))
+		goto out;
+
+	if (copy_from_user(&params, optval, optlen)) {
+		retval = -EFAULT;
+		goto out;
+	}
+
+	if (params.assoc_value & (~SCTP_ENABLE_STRRESET_MASK))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		asoc->strreset_enable = params.assoc_value;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		sp->ep->strreset_enable = params.assoc_value;
+	} else {
+		goto out;
+	}
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -3917,6 +3953,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_DEFAULT_PRINFO:
 		retval = sctp_setsockopt_default_prinfo(sk, optval, optlen);
 		break;
+	case SCTP_ENABLE_STREAM_RESET:
+		retval = sctp_setsockopt_enable_strreset(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
@@ -6401,6 +6440,47 @@ static int sctp_getsockopt_pr_assocstatus(struct sock *sk, int len,
 	return retval;
 }
 
+static int sctp_getsockopt_enable_strreset(struct sock *sk, int len,
+					   char __user *optval,
+					   int __user *optlen)
+{
+	struct sctp_assoc_value params;
+	struct sctp_association *asoc;
+	int retval = -EFAULT;
+
+	if (len < sizeof(params)) {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	len = sizeof(params);
+	if (copy_from_user(&params, optval, len))
+		goto out;
+
+	asoc = sctp_id2assoc(sk, params.assoc_id);
+	if (asoc) {
+		params.assoc_value = asoc->strreset_enable;
+	} else if (!params.assoc_id) {
+		struct sctp_sock *sp = sctp_sk(sk);
+
+		params.assoc_value = sp->ep->strreset_enable;
+	} else {
+		retval = -EINVAL;
+		goto out;
+	}
+
+	if (put_user(len, optlen))
+		goto out;
+
+	if (copy_to_user(optval, &params, len))
+		goto out;
+
+	retval = 0;
+
+out:
+	return retval;
+}
+
 static int sctp_getsockopt(struct sock *sk, int level, int optname,
 			   char __user *optval, int __user *optlen)
 {
@@ -6568,6 +6648,10 @@ static int sctp_getsockopt(struct sock *sk, int level, int optname,
 		retval = sctp_getsockopt_pr_assocstatus(sk, len, optval,
 							optlen);
 		break;
+	case SCTP_ENABLE_STREAM_RESET:
+		retval = sctp_getsockopt_enable_strreset(sk, len, optval,
+							 optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
-- 
2.1.0

[PATCHv4 net-next 6/6] sctp: implement sender-side procedures for SSN Reset Request Parameter

[Xin Long]

This patch 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.

It is also add sockopt SCTP_RESET_STREAMS in rfc6525 section 6.3.2
for users.

Note that the new asoc member strreset_outstanding is to make sure
only one reconf request chunk on the fly as rfc6525 section 5.1.1
demands.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
---
 include/net/sctp/sctp.h    |  6 ++++
 include/net/sctp/structs.h |  1 +
 include/uapi/linux/sctp.h  | 11 +++++++
 net/sctp/outqueue.c        | 33 +++++++++++++------
 net/sctp/socket.c          | 29 +++++++++++++++++
 net/sctp/stream.c          | 79 ++++++++++++++++++++++++++++++++++++++++++++++
 6 files changed, 149 insertions(+), 10 deletions(-)

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index bc0e049..3cfd365b 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -194,6 +194,12 @@ 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
  */
 
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index d99b76e..231fa9ac 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -1875,6 +1875,7 @@ struct sctp_association {
 	     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 */
diff --git a/include/uapi/linux/sctp.h b/include/uapi/linux/sctp.h
index 867be0f..03c27ce 100644
--- a/include/uapi/linux/sctp.h
+++ b/include/uapi/linux/sctp.h
@@ -116,6 +116,7 @@ typedef __s32 sctp_assoc_t;
 #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
@@ -145,6 +146,9 @@ typedef __s32 sctp_assoc_t;
 #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 {
@@ -1015,4 +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 */
diff --git a/net/sctp/outqueue.c b/net/sctp/outqueue.c
index 34efaa4..65abe22 100644
--- a/net/sctp/outqueue.c
+++ b/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.
 			 */
diff --git a/net/sctp/socket.c b/net/sctp/socket.c
index ae07db4..e072bf7 100644
--- a/net/sctp/socket.c
+++ b/net/sctp/socket.c
@@ -3787,6 +3787,32 @@ static int sctp_setsockopt_enable_strreset(struct sock *sk,
 	return retval;
 }
 
+static int sctp_setsockopt_reset_streams(struct sock *sk,
+					 char __user *optval,
+					 unsigned int optlen)
+{
+	struct sctp_reset_streams *params;
+	struct sctp_association *asoc;
+	int retval = -EINVAL;
+
+	if (optlen < sizeof(struct sctp_reset_streams))
+		return -EINVAL;
+
+	params = memdup_user(optval, optlen);
+	if (IS_ERR(params))
+		return PTR_ERR(params);
+
+	asoc = sctp_id2assoc(sk, params->srs_assoc_id);
+	if (!asoc)
+		goto out;
+
+	retval = sctp_send_reset_streams(asoc, params);
+
+out:
+	kfree(params);
+	return retval;
+}
+
 /* API 6.2 setsockopt(), getsockopt()
  *
  * Applications use setsockopt() and getsockopt() to set or retrieve
@@ -3956,6 +3982,9 @@ static int sctp_setsockopt(struct sock *sk, int level, int optname,
 	case SCTP_ENABLE_STREAM_RESET:
 		retval = sctp_setsockopt_enable_strreset(sk, optval, optlen);
 		break;
+	case SCTP_RESET_STREAMS:
+		retval = sctp_setsockopt_reset_streams(sk, optval, optlen);
+		break;
 	default:
 		retval = -ENOPROTOOPT;
 		break;
diff --git a/net/sctp/stream.c b/net/sctp/stream.c
index f86de43..13d5e07 100644
--- a/net/sctp/stream.c
+++ b/net/sctp/stream.c
@@ -33,6 +33,7 @@
  */
 
 #include <net/sctp/sctp.h>
+#include <net/sctp/sm.h>
 
 struct sctp_stream *sctp_stream_new(__u16 incnt, __u16 outcnt, gfp_t gfp)
 {
@@ -83,3 +84,81 @@ void sctp_stream_clear(struct sctp_stream *stream)
 	for (i = 0; i < stream->incnt; i++)
 		stream->in[i].ssn = 0;
 }
+
+static int sctp_send_reconf(struct sctp_association *asoc,
+			    struct sctp_chunk *chunk)
+{
+	struct net *net = sock_net(asoc->base.sk);
+	int retval = 0;
+
+	retval = sctp_primitive_RECONF(net, asoc, chunk);
+	if (retval)
+		sctp_chunk_free(chunk);
+
+	return retval;
+}
+
+int sctp_send_reset_streams(struct sctp_association *asoc,
+			    struct sctp_reset_streams *params)
+{
+	struct sctp_stream *stream = asoc->stream;
+	__u16 i, str_nums, *str_list;
+	struct sctp_chunk *chunk;
+	int retval = -EINVAL;
+	bool out, in;
+
+	if (!asoc->peer.reconf_capable ||
+	    !(asoc->strreset_enable & SCTP_ENABLE_RESET_STREAM_REQ)) {
+		retval = -ENOPROTOOPT;
+		goto out;
+	}
+
+	if (asoc->strreset_outstanding) {
+		retval = -EINPROGRESS;
+		goto out;
+	}
+
+	out = params->srs_flags & SCTP_STREAM_RESET_OUTGOING;
+	in  = params->srs_flags & SCTP_STREAM_RESET_INCOMING;
+	if (!out && !in)
+		goto out;
+
+	str_nums = params->srs_number_streams;
+	str_list = params->srs_stream_list;
+	if (out && str_nums)
+		for (i = 0; i < str_nums; i++)
+			if (str_list[i] >= stream->outcnt)
+				goto out;
+
+	if (in && str_nums)
+		for (i = 0; i < str_nums; i++)
+			if (str_list[i] >= stream->incnt)
+				goto out;
+
+	chunk = sctp_make_strreset_req(asoc, str_nums, str_list, out, in);
+	if (!chunk)
+		goto out;
+
+	if (out) {
+		if (str_nums)
+			for (i = 0; i < str_nums; i++)
+				stream->out[str_list[i]].state +						       SCTP_STREAM_CLOSED;
+		else
+			for (i = 0; i < stream->outcnt; i++)
+				stream->out[i].state = SCTP_STREAM_CLOSED;
+	}
+
+	asoc->strreset_outstanding = out + in;
+	asoc->strreset_chunk = chunk;
+	sctp_chunk_hold(asoc->strreset_chunk);
+
+	retval = sctp_send_reconf(asoc, chunk);
+	if (retval) {
+		sctp_chunk_put(asoc->strreset_chunk);
+		asoc->strreset_chunk = NULL;
+	}
+
+out:
+	return retval;
+}
-- 
2.1.0

Re: [PATCHv4 net-next 0/6] sctp: add sender-side procedures for stream reconf ssn reset request chun

[David Miller]

From: Xin Long <lucien.xin@gmail.com>
Date: Wed, 18 Jan 2017 00:44:41 +0800

> 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.

Series applied, thank you.