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 #define NETDISSECT_REWORKED
34 #ifdef HAVE_CONFIG_H
35 #include "config.h"
36 #endif
37
38 #include <tcpdump-stdinc.h>
39
40 #include "interface.h"
41 #include "extract.h"
42 #include "openflow.h"
43 #include "oui.h"
44
45 static const char tstr[] = " [|openflow]";
46 static const char cstr[] = " (corrupt)";
47
48 #define OF_VER_1_0 0x01
49
50 const 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
62 const char *
of_vendor_name(const uint32_t vendor)63 of_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
69 static void
of_header_print(netdissect_options * ndo,const uint8_t version,const uint8_t type,const uint16_t length,const uint32_t xid)70 of_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. */
78 static const u_char *
of_header_body_print(netdissect_options * ndo,const u_char * cp,const u_char * ep)79 of_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 corrupt;
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 corrupt;
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
123 corrupt: /* fail current packet */
124 ND_PRINT((ndo, "%s", cstr));
125 ND_TCHECK2(*cp, ep - cp);
126 return ep;
127 trunc:
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. */
134 void
openflow_print(netdissect_options * ndo,const u_char * cp,const u_int len)135 openflow_print(netdissect_options *ndo, const u_char *cp, const u_int len)
136 {
137 const u_char *ep = cp + len;
138
139 ND_PRINT((ndo, ": OpenFlow"));
140 while (cp < ep)
141 cp = of_header_body_print(ndo, cp, ep);
142 }
143