Added retransmissions to TCP

diff --git a/src/include/gpxe/tcp.h b/src/include/gpxe/tcp.h
index 2056afdc91ea094676eccfd8345452507fd5da97..ca926a5c2b89839f80183ebe84d8d17182f8ab65 100644 (file)
--- a/src/include/gpxe/tcp.h
+++ b/src/include/gpxe/tcp.h
@@ -13,6 +13,7 @@
 #include <gpxe/list.h>
 #include <gpxe/tcpip.h>
 #include <gpxe/pkbuff.h>
+#include <gpxe/retry.h>
 
 struct tcp_connection;
 
@@ -157,9 +158,14 @@ struct tcp_connection {
        uint8_t tcp_flags;              /* TCP header flags */
        struct list_head list;          /* List of TCP connections */
        struct pk_buff *tx_pkb;         /* Transmit packet buffer */
+       struct retry_timer timer;       /* Retransmission timer */
+       int retransmits;                /* Number of retransmits */
        struct tcp_operations *tcp_op;  /* Operations table for connection */
 };
 
+/** Retry timer values */
+#define MAX_RETRANSMITS        3
+
 /**
  * Connection closed status codes
  */

diff --git a/src/net/tcp.c b/src/net/tcp.c
index c9b4c43300dd60c388e7d6ee7adcc9ae35cfc7a2..2450f45ab79cc9486cb40d6f6df88bad6cf07f2a 100644 (file)
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -11,6 +11,7 @@
 #include <gpxe/ip.h>
 #include <gpxe/tcp.h>
 #include <gpxe/tcpip.h>
+#include <gpxe/retry.h>
 #include "uip/uip.h"
 
 /** @file
@@ -369,6 +370,58 @@ void tcp_init_conn ( struct tcp_connection *conn ) {
        conn->tcp_op = NULL;
 }
 
+/** Retry timer
+ *
+ * @v timer    Retry timer
+ * @v over     Failure indicator
+ */
+void tcp_expired ( struct retry_timer *timer, int over ) {
+       struct tcp_connection *conn;
+       if ( over ) {
+               conn = ( struct tcp_connection * ) container_of ( timer, 
+                                               struct tcp_connection, timer );
+               switch ( conn->tcp_state ) {
+               case TCP_SYN_SENT:
+                       if ( conn->retransmits > MAX_RETRANSMITS ) {
+                               tcp_trans ( conn, TCP_CLOSED );
+                               return;
+                       }
+                       if ( conn->tcp_lstate == TCP_CLOSED ||
+                            conn->tcp_lstate == TCP_LISTEN ) {
+                               goto send_tcp_nomsg;
+                       }
+                       return;
+               case TCP_SYN_RCVD:
+                       tcp_trans ( conn, TCP_CLOSED );
+                       if ( conn->tcp_lstate == TCP_LISTEN ||
+                            conn->tcp_lstate == TCP_SYN_SENT ) {
+                               goto send_tcp_nomsg;
+                       }
+                       return;
+               case TCP_ESTABLISHED:
+                       break;
+               case TCP_FIN_WAIT_1:
+               case TCP_FIN_WAIT_2:
+               case TCP_CLOSE_WAIT:
+                       goto send_tcp_nomsg;
+               case TCP_CLOSING:
+               case TCP_LAST_ACK:
+                       return;
+               case TCP_TIME_WAIT:
+                       tcp_trans ( conn, TCP_CLOSED );
+                       return;
+               }
+               /* Retransmit the data */
+               tcp_senddata ( conn );
+               conn->retransmits++;
+               return;
+
+  send_tcp_nomsg:
+               tcp_send ( conn, TCP_NOMSG, TCP_NOMSG_LEN );
+               return;
+       }
+}
+
 /**
  * Connect to a remote server
  *
@@ -396,6 +449,9 @@ int tcp_connectto ( struct tcp_connection *conn,
        }
        memcpy ( &conn->peer, peer, sizeof ( conn->peer ) );
 
+       /* Initialize the TCP timer */
+       conn->timer.expired = tcp_expired;
+
        /* Send a SYN packet and transition to TCP_SYN_SENT */
        conn->snd_una = ( ( ( uint32_t ) random() ) << 16 ) & random();
        tcp_trans ( conn, TCP_SYN_SENT );
@@ -577,6 +633,9 @@ int tcp_send ( struct tcp_connection *conn, const void *data, size_t len ) {
        /* Dump the TCP header */
        tcp_dump ( tcphdr );
 
+       /* Start the timer */
+       start_timer ( &conn->timer );
+
        /* Transmit packet */
        return tcpip_tx ( pkb, &tcp_protocol, peer );
 }
@@ -624,6 +683,10 @@ static int tcp_rx ( struct pk_buff *pkb,
        return 0;
 
   found_conn:
+       /* Stop the timer */
+       stop_timer ( &conn->timer );
+       conn->retransmits = 0;
+
        /* Set the advertised window */
        conn->snd_win = tcphdr->win;