xref: /netbsd-src/external/bsd/tcpdump/dist/print-openflow.c (revision 63372caa2f74032c7c1cb34e7cd32f28ad65b703)
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 #include <sys/cdefs.h>
34 #ifndef lint
35 __RCSID("$NetBSD: print-openflow.c,v 1.6 2024/09/02 16:15:32 christos Exp $");
36 #endif
37 
38 /* \summary: version-independent OpenFlow printer */
39 
40 #include <config.h>
41 
42 #include "netdissect-stdinc.h"
43 
44 #define ND_LONGJMP_FROM_TCHECK
45 #include "netdissect.h"
46 #include "extract.h"
47 #include "openflow.h"
48 #include "oui.h"
49 
50 
51 static const struct tok ofver_str[] = {
52 	{ OF_VER_1_0,	"1.0" },
53 	{ OF_VER_1_1,	"1.1" },
54 	{ OF_VER_1_2,	"1.2" },
55 	{ OF_VER_1_3,	"1.3" },
56 	{ OF_VER_1_4,	"1.4" },
57 	{ OF_VER_1_5,	"1.5" },
58 	{ 0, NULL }
59 };
60 
61 const struct tok onf_exp_str[] = {
62 	{ ONF_EXP_ONF,               "ONF Extensions"                                  },
63 	{ ONF_EXP_BUTE,              "Budapest University of Technology and Economics" },
64 	{ ONF_EXP_NOVIFLOW,          "NoviFlow"                                        },
65 	{ ONF_EXP_L3,                "L3+ Extensions, Vendor Neutral"                  },
66 	{ ONF_EXP_L4L7,              "L4-L7 Extensions"                                },
67 	{ ONF_EXP_WMOB,              "Wireless and Mobility Extensions"                },
68 	{ ONF_EXP_FABS,              "Forwarding Abstractions Extensions"              },
69 	{ ONF_EXP_OTRANS,            "Optical Transport Extensions"                    },
70 	{ ONF_EXP_NBLNCTU,           "Network Benchmarking Lab, NCTU"                  },
71 	{ ONF_EXP_MPCE,              "Mobile Packet Core Extensions"                   },
72 	{ ONF_EXP_MPLSTPSPTN,        "MPLS-TP OpenFlow Extensions for SPTN"            },
73 	{ 0, NULL }
74 };
75 
76 const char *
77 of_vendor_name(const uint32_t vendor)
78 {
79 	const struct tok *table = (vendor & 0xff000000) == 0 ? oui_values : onf_exp_str;
80 	return tok2str(table, "unknown", vendor);
81 }
82 
83 void
84 of_bitmap_print(netdissect_options *ndo,
85                 const struct tok *t, const uint32_t v, const uint32_t u)
86 {
87 	/* Assigned bits? */
88 	if (v & ~u)
89 		ND_PRINT(" (%s)", bittok2str(t, "", v));
90 	/* Unassigned bits? */
91 	if (v & u)
92 		ND_PRINT(" (bogus)");
93 }
94 
95 void
96 of_data_print(netdissect_options *ndo,
97               const u_char *cp, const u_int len)
98 {
99 	if (len == 0)
100 		return;
101 	/* data */
102 	ND_PRINT("\n\t data (%u octets)", len);
103 	if (ndo->ndo_vflag >= 2)
104 		hex_and_ascii_print(ndo, "\n\t  ", cp, len);
105 	else
106 		ND_TCHECK_LEN(cp, len);
107 }
108 
109 static void
110 of_message_print(netdissect_options *ndo,
111                  const u_char *cp, uint16_t len,
112                  const struct of_msgtypeinfo *mti)
113 {
114 	/*
115 	 * Here "cp" and "len" stand for the message part beyond the common
116 	 * OpenFlow 1.0 header, if any.
117 	 *
118 	 * Most message types are longer than just the header, and the length
119 	 * constraints may be complex. When possible, validate the constraint
120 	 * completely here (REQ_FIXLEN), otherwise check that the message is
121 	 * long enough to begin the decoding (REQ_MINLEN) and have the
122 	 * type-specific function do any remaining validation.
123 	 */
124 
125 	if (!mti)
126 		goto tcheck_remainder;
127 
128 	if ((mti->req_what == REQ_FIXLEN && len != mti->req_value) ||
129 	    (mti->req_what == REQ_MINLEN && len <  mti->req_value))
130 		goto invalid;
131 
132 	if (!ndo->ndo_vflag || !mti->decoder)
133 		goto tcheck_remainder;
134 
135 	mti->decoder(ndo, cp, len);
136 	return;
137 
138 invalid:
139 	nd_print_invalid(ndo);
140 tcheck_remainder:
141 	ND_TCHECK_LEN(cp, len);
142 }
143 
144 /* Print a TCP segment worth of OpenFlow messages presuming the segment begins
145  * on a message boundary. */
146 void
147 openflow_print(netdissect_options *ndo, const u_char *cp, u_int len)
148 {
149 	ndo->ndo_protocol = "openflow";
150 	ND_PRINT(": OpenFlow");
151 	while (len) {
152 		/* Print a single OpenFlow message. */
153 		uint8_t version, type;
154 		uint16_t length;
155 		const struct of_msgtypeinfo *mti;
156 
157 		/* version */
158 		version = GET_U_1(cp);
159 		OF_FWD(1);
160 		ND_PRINT("\n\tversion %s",
161 		         tok2str(ofver_str, "unknown (0x%02x)", version));
162 		/* type */
163 		if (len < 1)
164 			goto partial_header;
165 		type = GET_U_1(cp);
166 		OF_FWD(1);
167 		mti =
168 			version == OF_VER_1_0 ? of10_identify_msgtype(type) :
169 			version == OF_VER_1_3 ? of13_identify_msgtype(type) :
170 			NULL;
171 		if (mti && mti->name)
172 			ND_PRINT(", type %s", mti->name);
173 		else
174 			ND_PRINT(", type unknown (0x%02x)", type);
175 		/* length */
176 		if (len < 2)
177 			goto partial_header;
178 		length = GET_BE_U_2(cp);
179 		OF_FWD(2);
180 		ND_PRINT(", length %u%s", length,
181 		         length < OF_HEADER_FIXLEN ? " (too short!)" : "");
182 		/* xid */
183 		if (len < 4)
184 			goto partial_header;
185 		ND_PRINT(", xid 0x%08x", GET_BE_U_4(cp));
186 		OF_FWD(4);
187 
188 		/*
189 		 * When a TCP packet can contain several protocol messages,
190 		 * and at the same time a protocol message can span several
191 		 * TCP packets, decoding an incomplete message at the end of
192 		 * a TCP packet requires attention to detail in this loop.
193 		 *
194 		 * Message length includes the header length and a message
195 		 * always includes the basic header. A message length underrun
196 		 * fails decoding of the rest of the current packet. At the
197 		 * same time, try decoding as much of the current message as
198 		 * possible even when it does not end within the current TCP
199 		 * segment.
200 		 *
201 		 * Specifically, to try to process the message body in this
202 		 * iteration do NOT require the header "length" to be small
203 		 * enough for the full declared OpenFlow message to fit into
204 		 * the remainder of the declared TCP segment, same as the full
205 		 * declared TCP segment is not required to fit into the
206 		 * captured packet buffer.
207 		 *
208 		 * But DO require the same at the end of this iteration to
209 		 * decrement "len" and to proceed to the next iteration.
210 		 * (Ideally the declared TCP payload end will be at or after
211 		 * the captured packet buffer end, but stay safe even when
212 		 * that's somehow not the case.)
213 		 */
214 		if (length < OF_HEADER_FIXLEN)
215 			goto invalid;
216 
217 		of_message_print(ndo, cp, length - OF_HEADER_FIXLEN, mti);
218 		if (length - OF_HEADER_FIXLEN > len)
219 			break;
220 		OF_FWD(length - OF_HEADER_FIXLEN);
221 	} /* while (len) */
222 	return;
223 
224 partial_header:
225 	ND_PRINT(" (end of TCP payload)");
226 	ND_TCHECK_LEN(cp, len);
227 	return;
228 invalid: /* fail the current packet */
229 	nd_print_invalid(ndo);
230 	ND_TCHECK_LEN(cp, len);
231 }
232