[DCCP]: Update code comments for Step 2/3

Sorts out the comments for processing steps 2,3 in section 8.5 of RFC 4340.
All comments have been updated against this document, and the reference to step
2 has been made consistent throughout the files.

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/ipv6.c b/net/dccp/ipv6.c
index 19a4f76..201801e 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -487,10 +487,10 @@
 	/*
 	 * Step 3: Process LISTEN state
 	 *
-	 * Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
+	 *   Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
 	 *
-	 * In fact we defer setting S.GSR, S.SWL, S.SWH to
-	 * dccp_create_openreq_child.
+	 *   In fact we defer setting S.GSR, S.SWL, S.SWH to
+	 *   dccp_create_openreq_child.
 	 */
 	dreq = dccp_rsk(req);
 	dreq->dreq_isr	   = dcb->dccpd_seq;
@@ -760,6 +760,30 @@
 		return 0;
 	}
 
+	/*
+	 *  Step 3: Process LISTEN state
+	 *     If S.state == LISTEN,
+	 *	 If P.type == Request or P contains a valid Init Cookie option,
+	 *	      (* Must scan the packet's options to check for Init
+	 *		 Cookies.  Only Init Cookies are processed here,
+	 *		 however; other options are processed in Step 8.  This
+	 *		 scan need only be performed if the endpoint uses Init
+	 *		 Cookies *)
+	 *	      (* Generate a new socket and switch to that socket *)
+	 *	      Set S := new socket for this port pair
+	 *	      S.state = RESPOND
+	 *	      Choose S.ISS (initial seqno) or set from Init Cookies
+	 *	      Initialize S.GAR := S.ISS
+	 *	      Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookies
+	 *	      Continue with S.state == RESPOND
+	 *	      (* A Response packet will be generated in Step 11 *)
+	 *	 Otherwise,
+	 *	      Generate Reset(No Connection) unless P.type == Reset
+	 *	      Drop packet and return
+	 *
+	 * NOTE: the check for the packet types is done in
+	 *	 dccp_rcv_state_process
+	 */
 	if (sk->sk_state == DCCP_LISTEN) {
 		struct sock *nsk = dccp_v6_hnd_req(sk, skb);
 
@@ -826,8 +850,6 @@
 	/*
 	 * Step 2:
 	 * 	If no socket ...
-	 *		Generate Reset(No Connection) unless P.type == Reset
-	 *		Drop packet and return
 	 */
 	if (sk == NULL) {
 		dccp_pr_debug("failed to look up flow ID in table and "
@@ -857,6 +879,7 @@
 		goto discard_it;
 	/*
 	 * Step 2:
+	 * 	If no socket ...
 	 *		Generate Reset(No Connection) unless P.type == Reset
 	 *		Drop packet and return
 	 */