[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>

1 files changed, 28 insertions, 5 deletions

diff --git a/net/dccp/ipv6.c b/net/dccp/ipv6.c
index 19a4f763099d..201801e1532d 100644
--- a/net/dccp/ipv6.c
+++ b/net/dccp/ipv6.c
@@ -487,10 +487,10 @@ static int dccp_v6_conn_request(struct sock *sk, struct sk_buff *skb)
         /*
          * 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 @@ static int dccp_v6_do_rcv(struct sock *sk, struct sk_buff *skb)
                 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 @@ static int dccp_v6_rcv(struct sk_buff **pskb)
         /*
          * 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 @@ no_dccp_socket:
                 goto discard_it;
         /*
          * Step 2:
+         *      If no socket ...
          *              Generate Reset(No Connection) unless P.type == Reset
          *              Drop packet and return
          */