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 81 of_bitmap_print(netdissect_options *ndo, 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 93 of_data_print(netdissect_options *ndo, 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 107 of_message_print(netdissect_options *ndo, 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 = 165 version == OF_VER_1_0 ? of10_identify_msgtype(type) : 166 version == OF_VER_1_3 ? of13_identify_msgtype(type) : 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 } 229