tcpdump  4.99.1
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print-openflow.c
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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 #define ND_LONGJMP_FROM_TCHECK
42 #include "netdissect.h"
43 #include "extract.h"
44 #include "openflow.h"
45 #include "oui.h"
46 
47 
48 static const struct tok ofver_str[] = {
49  { OF_VER_1_0, "1.0" },
50  { OF_VER_1_1, "1.1" },
51  { OF_VER_1_2, "1.2" },
52  { OF_VER_1_3, "1.3" },
53  { OF_VER_1_4, "1.4" },
54  { OF_VER_1_5, "1.5" },
55  { 0, NULL }
56 };
57 
58 const struct tok onf_exp_str[] = {
59  { ONF_EXP_ONF, "ONF Extensions" },
60  { ONF_EXP_BUTE, "Budapest University of Technology and Economics" },
61  { ONF_EXP_NOVIFLOW, "NoviFlow" },
62  { ONF_EXP_L3, "L3+ Extensions, Vendor Neutral" },
63  { ONF_EXP_L4L7, "L4-L7 Extensions" },
64  { ONF_EXP_WMOB, "Wireless and Mobility Extensions" },
65  { ONF_EXP_FABS, "Forwarding Abstractions Extensions" },
66  { ONF_EXP_OTRANS, "Optical Transport Extensions" },
67  { ONF_EXP_NBLNCTU, "Network Benchmarking Lab, NCTU" },
68  { ONF_EXP_MPCE, "Mobile Packet Core Extensions" },
69  { ONF_EXP_MPLSTPSPTN, "MPLS-TP OpenFlow Extensions for SPTN" },
70  { 0, NULL }
71 };
72 
73 const char *
74 of_vendor_name(const uint32_t vendor)
75 {
76  const struct tok *table = (vendor & 0xff000000) == 0 ? oui_values : onf_exp_str;
77  return tok2str(table, "unknown", vendor);
78 }
79 
80 void
82  const struct tok *t, const uint32_t v, const uint32_t u)
83 {
84  /* Assigned bits? */
85  if (v & ~u)
86  ND_PRINT(" (%s)", bittok2str(t, "", v));
87  /* Unassigned bits? */
88  if (v & u)
89  ND_PRINT(" (bogus)");
90 }
91 
92 void
94  const u_char *cp, const u_int len)
95 {
96  if (len == 0)
97  return;
98  /* data */
99  ND_PRINT("\n\t data (%u octets)", len);
100  if (ndo->ndo_vflag >= 2)
101  hex_and_ascii_print(ndo, "\n\t ", cp, len);
102  else
103  ND_TCHECK_LEN(cp, len);
104 }
105 
106 static void
108  const u_char *cp, uint16_t len,
109  const struct of_msgtypeinfo *mti)
110 {
111  /*
112  * Here "cp" and "len" stand for the message part beyond the common
113  * OpenFlow 1.0 header, if any.
114  *
115  * Most message types are longer than just the header, and the length
116  * constraints may be complex. When possible, validate the constraint
117  * completely here (REQ_FIXLEN), otherwise check that the message is
118  * long enough to begin the decoding (REQ_MINLEN) and have the
119  * type-specific function do any remaining validation.
120  */
121 
122  if (!mti)
123  goto tcheck_remainder;
124 
125  if ((mti->req_what == REQ_FIXLEN && len != mti->req_value) ||
126  (mti->req_what == REQ_MINLEN && len < mti->req_value))
127  goto invalid;
128 
129  if (!ndo->ndo_vflag || !mti->decoder)
130  goto tcheck_remainder;
131 
132  mti->decoder(ndo, cp, len);
133  return;
134 
135 invalid:
136  nd_print_invalid(ndo);
137 tcheck_remainder:
138  ND_TCHECK_LEN(cp, len);
139 }
140 
141 /* Print a TCP segment worth of OpenFlow messages presuming the segment begins
142  * on a message boundary. */
143 void
144 openflow_print(netdissect_options *ndo, const u_char *cp, u_int len)
145 {
146  ndo->ndo_protocol = "openflow";
147  ND_PRINT(": OpenFlow");
148  while (len) {
149  /* Print a single OpenFlow message. */
150  uint8_t version, type;
151  uint16_t length;
152  const struct of_msgtypeinfo *mti;
153 
154  /* version */
155  version = GET_U_1(cp);
156  OF_FWD(1);
157  ND_PRINT("\n\tversion %s",
158  tok2str(ofver_str, "unknown (0x%02x)", version));
159  /* type */
160  if (len < 1)
161  goto partial_header;
162  type = GET_U_1(cp);
163  OF_FWD(1);
164  mti =
167  NULL;
168  if (mti && mti->name)
169  ND_PRINT(", type %s", mti->name);
170  else
171  ND_PRINT(", type unknown (0x%02x)", type);
172  /* length */
173  if (len < 2)
174  goto partial_header;
175  length = GET_BE_U_2(cp);
176  OF_FWD(2);
177  ND_PRINT(", length %u%s", length,
178  length < OF_HEADER_FIXLEN ? " (too short!)" : "");
179  /* xid */
180  if (len < 4)
181  goto partial_header;
182  ND_PRINT(", xid 0x%08x", GET_BE_U_4(cp));
183  OF_FWD(4);
184 
185  /*
186  * When a TCP packet can contain several protocol messages,
187  * and at the same time a protocol message can span several
188  * TCP packets, decoding an incomplete message at the end of
189  * a TCP packet requires attention to detail in this loop.
190  *
191  * Message length includes the header length and a message
192  * always includes the basic header. A message length underrun
193  * fails decoding of the rest of the current packet. At the
194  * same time, try decoding as much of the current message as
195  * possible even when it does not end within the current TCP
196  * segment.
197  *
198  * Specifically, to try to process the message body in this
199  * iteration do NOT require the header "length" to be small
200  * enough for the full declared OpenFlow message to fit into
201  * the remainder of the declared TCP segment, same as the full
202  * declared TCP segment is not required to fit into the
203  * captured packet buffer.
204  *
205  * But DO require the same at the end of this iteration to
206  * decrement "len" and to proceed to the next iteration.
207  * (Ideally the declared TCP payload end will be at or after
208  * the captured packet buffer end, but stay safe even when
209  * that's somehow not the case.)
210  */
211  if (length < OF_HEADER_FIXLEN)
212  goto invalid;
213 
214  of_message_print(ndo, cp, length - OF_HEADER_FIXLEN, mti);
215  if (length - OF_HEADER_FIXLEN > len)
216  break;
217  OF_FWD(length - OF_HEADER_FIXLEN);
218  } /* while (len) */
219  return;
220 
221 partial_header:
222  ND_PRINT(" (end of TCP payload)");
223  ND_TCHECK_LEN(cp, len);
224  return;
225 invalid: /* fail the current packet */
226  nd_print_invalid(ndo);
227  ND_TCHECK_LEN(cp, len);
228 }
#define GET_BE_U_4(p)
Definition: extract.h:877
#define GET_BE_U_2(p)
Definition: extract.h:875
#define GET_U_1(p)
Definition: extract.h:872
#define ND_TCHECK_LEN(p, l)
Definition: netdissect.h:368
const char * tok2str(const struct tok *, const char *, u_int)
Definition: util-print.c:485
char * bittok2str(const struct tok *, const char *, u_int)
Definition: util-print.c:558
void nd_print_invalid(netdissect_options *)
Definition: util-print.c:429
#define ND_PRINT(...)
Definition: netdissect.h:385
void hex_and_ascii_print(netdissect_options *, const char *, const u_char *, u_int)
Definition: print-ascii.c:165
#define OF_FWD(n)
Definition: openflow.h:33
#define OF_VER_1_1
Definition: openflow.h:45
#define ONF_EXP_FABS
Definition: openflow.h:59
#define ONF_EXP_BUTE
Definition: openflow.h:54
#define ONF_EXP_MPCE
Definition: openflow.h:62
#define ONF_EXP_OTRANS
Definition: openflow.h:60
const struct of_msgtypeinfo * of13_identify_msgtype(const uint8_t)
#define OF_VER_1_5
Definition: openflow.h:49
#define ONF_EXP_L3
Definition: openflow.h:56
#define OF_VER_1_3
Definition: openflow.h:47
#define ONF_EXP_NOVIFLOW
Definition: openflow.h:55
#define ONF_EXP_ONF
Definition: openflow.h:53
#define OF_VER_1_4
Definition: openflow.h:48
#define OF_VER_1_0
Definition: openflow.h:44
const struct of_msgtypeinfo * of10_identify_msgtype(const uint8_t)
#define ONF_EXP_L4L7
Definition: openflow.h:57
#define ONF_EXP_WMOB
Definition: openflow.h:58
#define OF_VER_1_2
Definition: openflow.h:46
#define ONF_EXP_MPLSTPSPTN
Definition: openflow.h:63
#define ONF_EXP_NBLNCTU
Definition: openflow.h:61
#define OF_HEADER_FIXLEN
Definition: openflow.h:51
const struct tok oui_values[]
Definition: oui.c:26
u_int version
Definition: print-isakmp.c:645
void of_data_print(netdissect_options *ndo, const u_char *cp, const u_int len)
void of_bitmap_print(netdissect_options *ndo, const struct tok *t, const uint32_t v, const uint32_t u)
static void of_message_print(netdissect_options *ndo, const u_char *cp, uint16_t len, const struct of_msgtypeinfo *mti)
static const struct tok ofver_str[]
const char * of_vendor_name(const uint32_t vendor)
void openflow_print(netdissect_options *ndo, const u_char *cp, u_int len)
const struct tok onf_exp_str[]
const char * ndo_protocol
Definition: netdissect.h:218
uint16_t req_value
Definition: openflow.h:86
void(* decoder)(netdissect_options *ndo, const u_char *, const u_int)
Definition: openflow.h:80
enum of_msgtypeinfo::@9 req_what
const char * name
Definition: openflow.h:78
u_int v
Definition: netdissect.h:139