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