vconn: Add utility functions make_openflow() and update_openflow_length().

[sliver-openvswitch.git] / lib / vconn.c

diff --git a/lib/vconn.c b/lib/vconn.c
index 1fa83fa..f75f816 100644 (file)
--- a/lib/vconn.c
+++ b/lib/vconn.c
@@ -43,6 +43,7 @@
 #include "ofp-print.h"
 #include "openflow.h"
 #include "poll-loop.h"
+#include "random.h"
 #include "util.h"
 
 #define THIS_MODULE VLM_vconn
@@ -204,6 +205,14 @@ vconn_is_passive(const struct vconn *vconn)
     return vconn->class->accept != NULL;
 }
 
+/* Returns the IP address of the peer, or 0 if the peer is not connected over
+ * an IP-based protocol or if its IP address is not yet known. */
+uint32_t
+vconn_get_ip(const struct vconn *vconn) 
+{
+    return vconn->ip;
+}
+
 /* Tries to complete the connection on 'vconn', which must be an active
  * vconn.  If 'vconn''s connection is complete, returns 0 if the connection
  * was successful or a positive errno value if it failed.  If the
@@ -368,6 +377,48 @@ vconn_send_wait(struct vconn *vconn)
     vconn_wait(vconn, WAIT_SEND);
 }
 
+/* Allocates and returns the first byte of a buffer 'openflow_len' bytes long,
+ * containing an OpenFlow header with the given 'type' and a random transaction
+ * id.  Stores the new buffer in '*bufferp'.  The caller must free the buffer
+ * when it is no longer needed. */
+void *
+make_openflow(size_t openflow_len, uint8_t type, struct buffer **bufferp) 
+{
+    return make_openflow_xid(openflow_len, type, random_uint32(), bufferp);
+}
+
+/* Allocates and returns the first byte of a buffer 'openflow_len' bytes long,
+ * containing an OpenFlow header with the given 'type' and transaction id
+ * 'xid'.  Stores the new buffer in '*bufferp'.  The caller must free the
+ * buffer when it is no longer needed. */
+void *
+make_openflow_xid(size_t openflow_len, uint8_t type, uint32_t xid,
+                  struct buffer **bufferp)
+{
+    struct buffer *buffer;
+    struct ofp_header *oh;
+
+    assert(openflow_len >= sizeof *oh);
+    assert(openflow_len <= UINT16_MAX);
+    buffer = *bufferp = buffer_new(openflow_len);
+    oh = buffer_put_uninit(buffer, openflow_len);
+    memset(oh, 0, openflow_len);
+    oh->version = OFP_VERSION;
+    oh->type = type;
+    oh->length = htons(openflow_len);
+    oh->xid = xid;
+    return oh;
+}
+
+/* Updates the 'length' field of the OpenFlow message in 'buffer' to
+ * 'buffer->size'. */
+void
+update_openflow_length(struct buffer *buffer) 
+{
+    struct ofp_header *oh = buffer_at_assert(buffer, 0, sizeof *oh);
+    oh->length = htons(buffer->size); 
+}
+
 struct buffer *
 make_add_simple_flow(const struct flow *flow,
                      uint32_t buffer_id, uint16_t out_port, uint16_t max_idle)
@@ -440,6 +491,20 @@ make_buffered_packet_out(uint32_t buffer_id,
     return out;
 }
 
+/* Creates and returns an OFPT_ECHO_REQUEST message with an empty payload. */
+struct buffer *
+make_echo_request(void)
+{
+    struct ofp_header *rq;
+    struct buffer *out = buffer_new(sizeof *rq);
+    rq = buffer_put_uninit(out, sizeof *rq);
+    rq->version = OFP_VERSION;
+    rq->type = OFPT_ECHO_REQUEST;
+    rq->length = htons(sizeof *rq);
+    rq->xid = 0;
+    return out;
+}
+
 /* Creates and returns an OFPT_ECHO_REPLY message matching the
  * OFPT_ECHO_REQUEST message in 'rq'. */
 struct buffer *