dccp: send Confirm options only once

If a connection is in the OPEN state, remove feature negotiation Confirm
options from the list of options after sending them once; as such options
are NOT supposed to be retransmitted and are ONLY supposed to be sent in
response to a Change option (RFC 4340 6.2).

Signed-off-by: Samuel Jero <sj323707@ohio.edu>
Acked-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>

diff --git a/net/dccp/feat.c b/net/dccp/feat.c
index ad6f9e2..23cea0e 100644 (file)
--- a/net/dccp/feat.c
+++ b/net/dccp/feat.c
@@ -665,11 +665,22 @@ int dccp_feat_insert_opts(struct dccp_sock *dp, struct dccp_request_sock *dreq,
                        return -1;
                if (pos->needs_mandatory && dccp_insert_option_mandatory(skb))
                        return -1;
-               /*
-                * Enter CHANGING after transmitting the Change option (6.6.2).
-                */
-               if (pos->state == FEAT_INITIALISING)
-                       pos->state = FEAT_CHANGING;
+
+               if (skb->sk->sk_state == DCCP_OPEN &&
+                   (opt == DCCPO_CONFIRM_R || opt == DCCPO_CONFIRM_L)) {
+                       /*
+                        * Confirms don't get retransmitted (6.6.3) once the
+                        * connection is in state OPEN
+                        */
+                       dccp_feat_list_pop(pos);
+               } else {
+                       /*
+                        * Enter CHANGING after transmitting the Change
+                        * option (6.6.2).
+                        */
+                       if (pos->state == FEAT_INITIALISING)
+                               pos->state = FEAT_CHANGING;
+               }
        }
        return 0;
 }