The Tcpdump Group git mirrors - tcpdump/blob - 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
  47 #define OF_VER_1_0    0x01
  48
  49 const struct tok onf_exp_str[] = {
  50         { ONF_EXP_ONF,               "ONF Extensions"                                  },
  51         { ONF_EXP_BUTE,              "Budapest University of Technology and Economics" },
  52         { ONF_EXP_NOVIFLOW,          "NoviFlow"                                        },
  53         { ONF_EXP_L3,                "L3+ Extensions, Vendor Neutral"                  },
  54         { ONF_EXP_L4L7,              "L4-L7 Extensions"                                },
  55         { ONF_EXP_WMOB,              "Wireless and Mobility Extensions"                },
  56         { ONF_EXP_FABS,              "Forwarding Abstractions Extensions"              },
  57         { ONF_EXP_OTRANS,            "Optical Transport Extensions"                    },
  58         { 0, NULL }
  59 };
  60
  61 const char *
  62 of_vendor_name(const uint32_t vendor)
  63 {
  64         const struct tok *table = (vendor & 0xff000000) == 0 ? oui_values : onf_exp_str;
  65         return tok2str(table, "unknown", vendor);
  66 }
  67
  68 static void
  69 of_header_print(netdissect_options *ndo, const uint8_t version, const uint8_t type,
  70                       const uint16_t length, const uint32_t xid)
  71 {
  72         ND_PRINT("\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
  73                version, type, length, xid);
  74 }
  75
  76 /* Print a single OpenFlow message. */
  77 static const u_char *
  78 of_header_body_print(netdissect_options *ndo, const u_char *cp, const u_char *ep)
  79 {
  80         uint8_t version, type;
  81         uint16_t length;
  82         uint32_t xid;
  83
  84         if (ep < cp + OF_HEADER_LEN)
  85                 goto invalid;
  86         /* version */
  87         ND_TCHECK_1(cp);
  88         version = EXTRACT_U_1(cp);
  89         cp += 1;
  90         /* type */
  91         ND_TCHECK_1(cp);
  92         type = EXTRACT_U_1(cp);
  93         cp += 1;
  94         /* length */
  95         ND_TCHECK_2(cp);
  96         length = EXTRACT_BE_U_2(cp);
  97         cp += 2;
  98         /* xid */
  99         ND_TCHECK_4(cp);
 100         xid = EXTRACT_BE_U_4(cp);
 101         cp += 4;
 102         /* Message length includes the header length and a message always includes
 103          * the basic header. A message length underrun fails decoding of the rest of
 104          * the current packet. At the same time, try decoding as much of the current
 105          * message as possible even when it does not end within the current TCP
 106          * segment. */
 107         if (length < OF_HEADER_LEN) {
 108                 of_header_print(ndo, version, type, length, xid);
 109                 goto invalid;
 110         }
 111         /* Decode known protocol versions further without printing the header (the
 112          * type decoding is version-specific. */
 113         switch (version) {
 114         case OF_VER_1_0:
 115                 return of10_header_body_print(ndo, cp, ep, type, length, xid);
 116         default:
 117                 of_header_print(ndo, version, type, length, xid);
 118                 ND_TCHECK_LEN(cp, length - OF_HEADER_LEN);
 119                 return cp + length - OF_HEADER_LEN; /* done with current message */
 120         }
 121
 122 invalid: /* fail current packet */
 123         ND_PRINT("%s", istr);
 124         ND_TCHECK_LEN(cp, ep - cp);
 125         return ep;
 126 trunc:
 127         nd_print_trunc(ndo);
 128         return ep;
 129 }
 130
 131 /* Print a TCP segment worth of OpenFlow messages presuming the segment begins
 132  * on a message boundary. */
 133 void
 134 openflow_print(netdissect_options *ndo, const u_char *cp, const u_int len _U_)
 135 {
 136         ndo->ndo_protocol = "openflow";
 137         ND_PRINT(": OpenFlow");
 138         while (cp < ndo->ndo_snapend)
 139                 cp = of_header_body_print(ndo, cp, ndo->ndo_snapend);
 140 }