print-openflow.c revision 356341 
1/*
2 * This module implements printing of the very basic (version-independent)
3 * OpenFlow header and iteration over OpenFlow messages. It is intended for
4 * dispatching of version-specific OpenFlow message decoding.
5 *
6 *
7 * Copyright (c) 2013 The TCPDUMP project
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
22 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
23 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
25 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
26 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
27 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
29 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33/* \summary: version-independent OpenFlow printer */
34
35#ifdef HAVE_CONFIG_H
36#include "config.h"
37#endif
38
39#include <netdissect-stdinc.h>
40
41#include "netdissect.h"
42#include "extract.h"
43#include "openflow.h"
44#include "oui.h"
45
46static const char tstr[] = " [|openflow]";
47
48#define OF_VER_1_0    0x01
49
50const struct tok onf_exp_str[] = {
51	{ ONF_EXP_ONF,               "ONF Extensions"                                  },
52	{ ONF_EXP_BUTE,              "Budapest University of Technology and Economics" },
53	{ ONF_EXP_NOVIFLOW,          "NoviFlow"                                        },
54	{ ONF_EXP_L3,                "L3+ Extensions, Vendor Neutral"                  },
55	{ ONF_EXP_L4L7,              "L4-L7 Extensions"                                },
56	{ ONF_EXP_WMOB,              "Wireless and Mobility Extensions"                },
57	{ ONF_EXP_FABS,              "Forwarding Abstractions Extensions"              },
58	{ ONF_EXP_OTRANS,            "Optical Transport Extensions"                    },
59	{ 0, NULL }
60};
61
62const char *
63of_vendor_name(const uint32_t vendor)
64{
65	const struct tok *table = (vendor & 0xff000000) == 0 ? oui_values : onf_exp_str;
66	return tok2str(table, "unknown", vendor);
67}
68
69static void
70of_header_print(netdissect_options *ndo, const uint8_t version, const uint8_t type,
71                      const uint16_t length, const uint32_t xid)
72{
73	ND_PRINT((ndo, "\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
74	       version, type, length, xid));
75}
76
77/* Print a single OpenFlow message. */
78static const u_char *
79of_header_body_print(netdissect_options *ndo, const u_char *cp, const u_char *ep)
80{
81	uint8_t version, type;
82	uint16_t length;
83	uint32_t xid;
84
85	if (ep < cp + OF_HEADER_LEN)
86		goto invalid;
87	/* version */
88	ND_TCHECK2(*cp, 1);
89	version = *cp;
90	cp += 1;
91	/* type */
92	ND_TCHECK2(*cp, 1);
93	type = *cp;
94	cp += 1;
95	/* length */
96	ND_TCHECK2(*cp, 2);
97	length = EXTRACT_16BITS(cp);
98	cp += 2;
99	/* xid */
100	ND_TCHECK2(*cp, 4);
101	xid = EXTRACT_32BITS(cp);
102	cp += 4;
103	/* Message length includes the header length and a message always includes
104	 * the basic header. A message length underrun fails decoding of the rest of
105	 * the current packet. At the same time, try decoding as much of the current
106	 * message as possible even when it does not end within the current TCP
107	 * segment. */
108	if (length < OF_HEADER_LEN) {
109		of_header_print(ndo, version, type, length, xid);
110		goto invalid;
111	}
112	/* Decode known protocol versions further without printing the header (the
113	 * type decoding is version-specific. */
114	switch (version) {
115	case OF_VER_1_0:
116		return of10_header_body_print(ndo, cp, ep, type, length, xid);
117	default:
118		of_header_print(ndo, version, type, length, xid);
119		ND_TCHECK2(*cp, length - OF_HEADER_LEN);
120		return cp + length - OF_HEADER_LEN; /* done with current message */
121	}
122
123invalid: /* fail current packet */
124	ND_PRINT((ndo, "%s", istr));
125	ND_TCHECK2(*cp, ep - cp);
126	return ep;
127trunc:
128	ND_PRINT((ndo, "%s", tstr));
129	return ep;
130}
131
132/* Print a TCP segment worth of OpenFlow messages presuming the segment begins
133 * on a message boundary. */
134void
135openflow_print(netdissect_options *ndo, const u_char *cp, const u_int len _U_)
136{
137	ND_PRINT((ndo, ": OpenFlow"));
138	while (cp < ndo->ndo_snapend)
139		cp = of_header_body_print(ndo, cp, ndo->ndo_snapend);
140}
141