sctp: add reconf_enable in asoc ep and netns

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

4 files changed, 20 insertions, 0 deletions

diff --git a/net/sctp/associola.c b/net/sctp/associola.c
index fc33540d2f11..68b99adc21a3 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 410ddc1e3443..8c589230794f 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 f9c3c37c9ae0..8227bbbd077a 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 df81fce08890..ad3445b3408e 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;