dccp: Per-socket initialisation of feature negotiation

This provides feature-negotiation initialisation for both DCCP sockets
and DCCP request_sockets, to support feature negotiation during
connection setup.

It also resolves a FIXME regarding the congestion control
initialisation.

Thanks to Wei Yongjun for help with the IPv6 side of this patch.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 1 deletions

diff --git a/net/dccp/minisocks.c b/net/dccp/minisocks.c
index e6bf99e3e41a..afdacbb94d75 100644
--- a/net/dccp/minisocks.c
+++ b/net/dccp/minisocks.c
@@ -125,6 +125,7 @@ struct sock *dccp_create_openreq_child(struct sock *sk,
                 newdp->dccps_timestamp_time = dreq->dreq_timestamp_time;
                 newicsk->icsk_rto           = DCCP_TIMEOUT_INIT;
 
+                INIT_LIST_HEAD(&newdp->dccps_featneg);
                 if (dccp_feat_clone(sk, newsk))
                         goto out_free;
 
@@ -304,7 +305,8 @@ void dccp_reqsk_send_ack(struct sock *sk, struct sk_buff *skb,
 
 EXPORT_SYMBOL_GPL(dccp_reqsk_send_ack);
 
-void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb)
+int dccp_reqsk_init(struct request_sock *req,
+                    struct dccp_sock const *dp, struct sk_buff const *skb)
 {
         struct dccp_request_sock *dreq = dccp_rsk(req);
 
@@ -313,6 +315,9 @@ void dccp_reqsk_init(struct request_sock *req, struct sk_buff *skb)
         inet_rsk(req)->acked      = 0;
         req->rcv_wnd              = sysctl_dccp_feat_sequence_window;
         dreq->dreq_timestamp_echo = 0;
+
+        /* inherit feature negotiation options from listening socket */
+        return dccp_feat_clone_list(&dp->dccps_featneg, &dreq->dreq_featneg);
 }
 
 EXPORT_SYMBOL_GPL(dccp_reqsk_init);