Port the UDP port allocation code to TCP

diff --git a/src/net/tcp.c b/src/net/tcp.c
index 8b8053b..f22c24e 100644 (file)
--- a/src/net/tcp.c
+++ b/src/net/tcp.c
@@ -529,35 +529,59 @@ int tcp_close ( struct tcp_connection *conn ) {
        return tcp_send ( conn, TCP_NOMSG, TCP_NOMSG_LEN );
 }
 
+/**
+ * Bind TCP connection to local port
+ *
+ * @v conn             TCP connection
+ * @v local_port       Local port, in network byte order
+ * @ret rc             Return status code
+ */
+int tcp_bind ( struct tcp_connection *conn, uint16_t local_port ) {
+       struct tcp_connection *existing;
+
+       list_for_each_entry ( existing, &tcp_conns, list ) {
+               if ( existing->local_port == local_port )
+                       return -EADDRINUSE;
+       }
+       conn->local_port = local_port;
+       return 0;
+}
+
 
 /**
  * Listen for a packet
  *
- * @v conn     TCP connection
- * @v port     Local port, in network byte order
+ * @v conn             TCP connection
+ * @v local_port       Local port, in network byte order
  *
- * This function adds the connection to a list of registered tcp connections. If
- * the local port is 0, the connection is assigned the lowest available port
- * between MIN_TCP_PORT and 65535.
+ * This function adds the connection to a list of registered tcp
+ * connections. If the local port is 0, the connection is assigned an
+ * available port between MIN_TCP_PORT and 65535.
  */
-int tcp_listen ( struct tcp_connection *conn, uint16_t port ) {
-       struct tcp_connection *cconn;
-       if ( port != 0 ) {
-               list_for_each_entry ( cconn, &tcp_conns, list ) {
-                       if ( cconn->local_port == port ) {
-                               DBG ( "Error listening to %d\n", 
-                                                       ntohs ( port ) );
-                               return -EISCONN;
-                       }
+int tcp_listen ( struct tcp_connection *conn, uint16_t local_port ) {
+       static uint16_t try_port = 1024;
+       int rc;
+
+       /* If no port specified, find the first available port */
+       if ( ! local_port ) {
+               for ( ; try_port ; try_port++ ) {
+                       if ( try_port < 1024 )
+                               continue;
+                       if ( tcp_listen ( conn, htons ( try_port ) ) == 0 )
+                               return 0;
                }
-               /* Add the connection to the list of registered connections */
-               conn->local_port = port;
-               list_add ( &conn->list, &tcp_conns );
-               return 0;
+               return -EADDRINUSE;
        }
-       /* Assigning lowest port not supported */
-       DBG ( "Assigning lowest port not implemented\n");
-       return -ENOSYS;
+
+       /* Attempt bind to local port */
+       if ( ( rc = tcp_bind ( conn, local_port ) ) != 0 )
+               return rc;
+
+       /* Add to TCP connection list */
+       list_add ( &conn->list, &tcp_conns );
+       DBG ( "TCP opened %p on port %d\n", conn, ntohs ( local_port ) );
+
+       return 0;
 }
 
 /**