[DCCP]: Revert patch which disables bidirectional mode

This reverts an earlier patch which disabled bidirectional mode, meaning that
a listening (passive) socket was not allowed to write to the other (active)
end of the connection.

This mode had been disabled when there were problems with CCID3, but it
imposes a constraint on socket programming and thus hinders deployment.

A change is included to ignore RX feedback received by the TX CCID3 module.

Many thanks to Andre Noll for pointing out this issue.

Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 5 insertions, 23 deletions

diff --git a/net/dccp/ccids/ccid3.c b/net/dccp/ccids/ccid3.c
index 5361a4d8e13b..746f79d104b3 100644
--- a/net/dccp/ccids/ccid3.c
+++ b/net/dccp/ccids/ccid3.c
@@ -545,12 +545,7 @@ static void ccid3_hc_tx_packet_recv(struct sock *sk, struct sk_buff *skb)
                 /* set idle flag */
                 hctx->ccid3hctx_idle = 1;
                 break;
-        case TFRC_SSTATE_NO_SENT:
-                /*
-                 * XXX when implementing bidirectional rx/tx check this again
-                 */
-                DCCP_WARN("Illegal ACK received - no packet sent\n");
-                /* fall through */
+        case TFRC_SSTATE_NO_SENT:       /* fall through */
         case TFRC_SSTATE_TERM:          /* ignore feedback when closing */
                 break;
         }
diff --git a/net/dccp/input.c b/net/dccp/input.c
index 287099f7f042..78b043c458bf 100644
--- a/net/dccp/input.c
+++ b/net/dccp/input.c
@@ -248,18 +248,8 @@ int dccp_rcv_established(struct sock *sk, struct sk_buff *skb,
                             DCCP_ACKVEC_STATE_RECEIVED))
                 goto discard;
 
-        /*
-         * Deliver to the CCID module in charge.
-         * FIXME: Currently DCCP operates one-directional only, i.e. a listening
-         *        server is not at the same time a connecting client. There is
-         *        not much sense in delivering to both rx/tx sides at the moment
-         *        (only one is active at a time); when moving to bidirectional
-         *        service, this needs to be revised.
-         */
-        if (dccp_sk(sk)->dccps_role == DCCP_ROLE_CLIENT)
-                ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
-        else    /* listening or connected server */
-                ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
+        ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
+        ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
 
         return __dccp_rcv_established(sk, skb, dh, len);
 discard:
@@ -494,11 +484,8 @@ int dccp_rcv_state_process(struct sock *sk, struct sk_buff *skb,
                                     DCCP_ACKVEC_STATE_RECEIVED))
                         goto discard;
 
-                /* XXX see the comments in dccp_rcv_established about this */
-                if (dccp_sk(sk)->dccps_role == DCCP_ROLE_CLIENT)
-                        ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
-                else
-                        ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
+                ccid_hc_rx_packet_recv(dp->dccps_hc_rx_ccid, sk, skb);
+                ccid_hc_tx_packet_recv(dp->dccps_hc_tx_ccid, sk, skb);
         }
 
         /*