--- /dev/null
+/*
+ * This module implements printing of the very basic (version-independent)
+ * OpenFlow header and iteration over OpenFlow messages. It is intended for
+ * dispatching of version-specific OpenFlow message decoding.
+ *
+ *
+ * Copyright (c) 2013 The TCPDUMP project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <tcpdump-stdinc.h>
+
+#include "interface.h"
+#include "extract.h"
+
+#define OF_HEADER_LEN 8
+
+static void
+of_header_print(const uint8_t version, const uint8_t type,
+ const uint16_t length, const uint32_t xid) {
+ printf("\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
+ version, type, length, xid);
+}
+
+/* Print a single OpenFlow message. */
+static const u_char *
+of_header_body_print(const u_char *cp, const u_char *ep) {
+ uint8_t version, type;
+ uint16_t length;
+ uint32_t xid;
+
+ if (ep < cp + OF_HEADER_LEN)
+ goto corrupt;
+ /* version */
+ TCHECK2(*cp, 1);
+ version = *cp;
+ cp += 1;
+ /* type */
+ TCHECK2(*cp, 1);
+ type = *cp;
+ cp += 1;
+ /* length */
+ TCHECK2(*cp, 2);
+ length = EXTRACT_16BITS(cp);
+ cp += 2;
+ /* xid */
+ TCHECK2(*cp, 4);
+ xid = EXTRACT_32BITS(cp);
+ cp += 4;
+ /* Message length includes the header length and a message always includes
+ * the basic header. A message length underrun fails decoding of the rest of
+ * the current packet. At the same time, try decoding as much of the current
+ * message as possible even when it does not end within the current TCP
+ * segment. */
+ if (length < OF_HEADER_LEN) {
+ of_header_print(version, type, length, xid);
+ goto corrupt;
+ }
+ /* Decode known protocol versions further without printing the header (the
+ * type decoding is version-specific. */
+ switch (version) {
+ default:
+ of_header_print(version, type, length, xid);
+ TCHECK2(*cp, length - OF_HEADER_LEN);
+ return cp + length - OF_HEADER_LEN; /* done with current message */
+ }
+
+corrupt: /* fail current packet */
+ printf(" (corrupt)");
+ TCHECK2(*cp, ep - cp);
+ return ep;
+trunc:
+ printf(" [|openflow]");
+ return ep;
+}
+
+/* Print a TCP segment worth of OpenFlow messages presuming the segment begins
+ * on a message boundary. */
+void
+openflow_print(const u_char *cp, const u_int len) {
+ const u_char *ep = cp + len;
+
+ printf(": OpenFlow");
+ while (cp < ep)
+ cp = of_header_body_print(cp, ep);
+}
projects / tcpdump / commitdiff
