[DCCPv6]: Choose a genuine initial sequence number

This
	* resolves a FIXME - DCCPv6 connections started all with
	  an initial sequence number of 1;
	* provides a redirection `secure_dccpv6_sequence_number'
	  in case the init_sequence_v6 code should be updated later;
	* concentrates the update of S.GAR into dccp_connect_init();
	* removes a duplicate dccp_update_gss() in ipv4.c;
	* uses inet->dport instead of usin->sin_port, due to the
	  following assignment in dccp_v4_connect():
 		inet->dport = usin->sin_port;

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
diff --git a/net/dccp/output.c b/net/dccp/output.c
index 08ee554..0994b13 100644
--- a/net/dccp/output.c
+++ b/net/dccp/output.c
@@ -448,7 +448,6 @@
 	
 	dccp_sync_mss(sk, dst_mtu(dst));
 
-	dccp_update_gss(sk, dp->dccps_iss);
  	/*
 	 * SWL and AWL are initially adjusted so that they are not less than
 	 * the initial Sequence Numbers received and sent, respectively:
@@ -457,8 +456,13 @@
 	 * These adjustments MUST be applied only at the beginning of the
 	 * connection.
  	 */
+	dccp_update_gss(sk, dp->dccps_iss);
 	dccp_set_seqno(&dp->dccps_awl, max48(dp->dccps_awl, dp->dccps_iss));
 
+	/* S.GAR - greatest valid acknowledgement number received on a non-Sync;
+	 *         initialized to S.ISS (sec. 8.5)                            */
+	dp->dccps_gar = dp->dccps_iss;
+
 	icsk->icsk_retransmits = 0;
 	init_timer(&dp->dccps_xmit_timer);
 	dp->dccps_xmit_timer.data = (unsigned long)sk;