[DCCP]: Fix RESET handling in dccp_rcv_state_process
Arnaldo Carvalho de Melo [Sat, 13 Aug 2005 23:36:01 +0000 (20:36 -0300)]
To avoid holding TIMEWAIT state for sockets in the LISTEN state.

Signed-off-by: Arnaldo Carvalho de Melo <acme@mandriva.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/dccp/input.c

index 4b8638f..9dadfc3 100644 (file)
@@ -402,7 +402,48 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
        const int old_state = sk->sk_state;
        int queued = 0;
 
-       if (sk->sk_state != DCCP_LISTEN && sk->sk_state != DCCP_REQUESTING) {
+       /*
+        *  Step 3: Process LISTEN state
+        *      (Continuing from dccp_v4_do_rcv and dccp_v6_do_rcv)
+        *
+        *     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 an Init
+        *              Cookie.  Only the Init Cookie is 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 Cookie
+        *           Set S.ISR, S.GSR, S.SWL, S.SWH from packet or Init Cookie
+        *           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) {
+               if (dh->dccph_type == DCCP_PKT_REQUEST) {
+                       if (dccp_v4_conn_request(sk, skb) < 0)
+                               return 1;
+
+                       /* FIXME: do congestion control initialization */
+                       goto discard;
+               }
+               if (dh->dccph_type == DCCP_PKT_RESET)
+                       goto discard;
+
+               /* Caller (dccp_v4_do_rcv) will send Reset(No Connection)*/
+               return 1;
+       }
+
+       if (sk->sk_state != DCCP_REQUESTING) {
                if (dccp_check_seqno(sk, skb))
                        goto discard;
 
@@ -484,23 +525,6 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
        case DCCP_CLOSED:
                return 1;
 
-       case DCCP_LISTEN:
-               if (dh->dccph_type == DCCP_PKT_ACK ||
-                   dh->dccph_type == DCCP_PKT_DATAACK)
-                       return 1;
-
-               if (dh->dccph_type == DCCP_PKT_RESET)
-                       goto discard;
-
-               if (dh->dccph_type == DCCP_PKT_REQUEST) {
-                       if (dccp_v4_conn_request(sk, skb) < 0)
-                               return 1;
-
-                       /* FIXME: do congestion control initialization */
-                       goto discard;
-               }
-               goto discard;
-
        case DCCP_REQUESTING:
                /* FIXME: do congestion control initialization */