Ensure we retransmit the SYNACK packet if we didn't get an ACK back for it.

[utcp] / utcp.c

diff --git a/utcp.c b/utcp.c
index 5eca4d3897a82eec6bbc1bca6de33c324fb73daa..47acf221318bca518eca4d88bdd7ba04b0982071 100644 (file)
--- a/utcp.c
+++ b/utcp.c
@@ -890,7 +890,7 @@ static void retransmit(struct utcp_connection *c) {
 
        struct utcp *utcp = c->utcp;
 
-       if (utcp->retransmit) {
+       if(utcp->retransmit) {
                utcp->retransmit(c);
        }
 
@@ -1352,6 +1352,8 @@ synack:
                                print_packet(c, "send", &pkt, sizeof(hdr));
                                utcp->send(utcp, &pkt, sizeof(hdr));
                        }
+
+                       start_retransmit_timer(c);
                } else {
                        // No, we don't want your packets, send a RST back
                        len = 1;
@@ -1713,7 +1715,7 @@ skip_ack:
                        }
 
                        c->rcv.irs = hdr.seq;
-                       c->rcv.nxt = hdr.seq;
+                       c->rcv.nxt = hdr.seq + 1;
 
                        if(c->shut_wr) {
                                c->snd.last++;
@@ -1722,7 +1724,6 @@ skip_ack:
                                set_state(c, ESTABLISHED);
                        }
 
-                       // TODO: notify application of this somehow.
                        break;
 
                case SYN_RECEIVED:
@@ -1736,8 +1737,8 @@ skip_ack:
                case CLOSING:
                case LAST_ACK:
                case TIME_WAIT:
-                       // Ehm, no. We should never receive a second SYN.
-                       return 0;
+                       // This could be a retransmission. Ignore the SYN flag, but send an ACK back.
+                       break;
 
                default:
 #ifdef UTCP_DEBUG
@@ -1745,9 +1746,6 @@ skip_ack:
 #endif
                        return 0;
                }
-
-               // SYN counts as one sequence number
-               c->rcv.nxt++;
        }
 
        // 6. Process new data