dccp: Integrate feature-negotiation insertion code

The patch implements insertion of feature negotiation at the server (listening
and request socket) and the client (connecting socket).

In dccp_insert_options(), several statements have been grouped together now
to achieve (it is hoped) better efficiency by reducing the number of tests
each packet has to go through:
 - Ack Vectors are sent if the packet is neither a Data or a Request packet;
 - a previous issue is corrected - feature negotiation options are allowed
   on DataAck packets (5.8).

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>

diff --git a/net/dccp/options.c b/net/dccp/options.c
index 20d5c72..86c7a20 100644 (file)
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -554,11 +554,25 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
            dccp_insert_option_ndp(sk, skb))
                return -1;
 
-       if (!dccp_packet_without_ack(skb)) {
-               if (dmsk->dccpms_send_ack_vector &&
-                   dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
-                   dccp_insert_option_ackvec(sk, skb))
+       if (DCCP_SKB_CB(skb)->dccpd_type != DCCP_PKT_DATA) {
+
+               /* Feature Negotiation */
+               if (dccp_feat_insert_opts(dp, NULL, skb))
                        return -1;
+
+               if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST) {
+                       /*
+                        * Obtain RTT sample from Request/Response exchange.
+                        * This is currently used in CCID 3 initialisation.
+                        */
+                       if (dccp_insert_option_timestamp(sk, skb))
+                               return -1;
+
+               } else if (dmsk->dccpms_send_ack_vector &&
+                          dccp_ackvec_pending(dp->dccps_hc_rx_ackvec) &&
+                          dccp_insert_option_ackvec(sk, skb)) {
+                               return -1;
+               }
        }
 
        if (dp->dccps_hc_rx_insert_options) {
@@ -567,14 +581,6 @@ int dccp_insert_options(struct sock *sk, struct sk_buff *skb)
                dp->dccps_hc_rx_insert_options = 0;
        }
 
-       /*
-        * Obtain RTT sample from Request/Response exchange.
-        * This is currently used in CCID 3 initialisation.
-        */
-       if (DCCP_SKB_CB(skb)->dccpd_type == DCCP_PKT_REQUEST &&
-           dccp_insert_option_timestamp(sk, skb))
-               return -1;
-
        if (dp->dccps_timestamp_echo != 0 &&
            dccp_insert_option_timestamp_echo(dp, NULL, skb))
                return -1;
@@ -587,6 +593,9 @@ int dccp_insert_options_rsk(struct dccp_request_sock *dreq, struct sk_buff *skb)
 {
        DCCP_SKB_CB(skb)->dccpd_opt_len = 0;
 
+       if (dccp_feat_insert_opts(NULL, dreq, skb))
+               return -1;
+
        if (dreq->dreq_timestamp_echo != 0 &&
            dccp_insert_option_timestamp_echo(NULL, dreq, skb))
                return -1;