contrib/tcpdump/print-openflow.c

   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 #include "netdissect.h"
  42 #include "extract.h"
  43 #include "openflow.h"
  44 #include "oui.h"
  45
  46 static const char tstr[] = " [|openflow]";
  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 *
  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
  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 *
  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 invalid;
  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 invalid;
 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 invalid: /* fail current packet */
 124         ND_PRINT((ndo, "%s", istr));
 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
 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 }