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 #define NETDISSECT_REWORKED
  34 #ifdef HAVE_CONFIG_H
  35 #include "config.h"
  36 #endif
  37
  38 #include <tcpdump-stdinc.h>
  39
  40 #include "interface.h"
  41 #include "extract.h"
  42 #include "openflow.h"
  43 #include "oui.h"
  44
  45 static const char tstr[] = " [|openflow]";
  46 static const char cstr[] = " (corrupt)";
  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         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         ND_PRINT((ndo, "\n\tversion unknown (0x%02x), type 0x%02x, length %u, xid 0x%08x",
  72                version, type, length, xid));
  73 }
  74
  75 /* Print a single OpenFlow message. */
  76 static const u_char *
  77 of_header_body_print(netdissect_options *ndo, const u_char *cp, const u_char *ep) {
  78         uint8_t version, type;
  79         uint16_t length;
  80         uint32_t xid;
  81
  82         if (ep < cp + OF_HEADER_LEN)
  83                 goto corrupt;
  84         /* version */
  85         ND_TCHECK2(*cp, 1);
  86         version = *cp;
  87         cp += 1;
  88         /* type */
  89         ND_TCHECK2(*cp, 1);
  90         type = *cp;
  91         cp += 1;
  92         /* length */
  93         ND_TCHECK2(*cp, 2);
  94         length = EXTRACT_16BITS(cp);
  95         cp += 2;
  96         /* xid */
  97         ND_TCHECK2(*cp, 4);
  98         xid = EXTRACT_32BITS(cp);
  99         cp += 4;
 100         /* Message length includes the header length and a message always includes
 101          * the basic header. A message length underrun fails decoding of the rest of
 102          * the current packet. At the same time, try decoding as much of the current
 103          * message as possible even when it does not end within the current TCP
 104          * segment. */
 105         if (length < OF_HEADER_LEN) {
 106                 of_header_print(ndo, version, type, length, xid);
 107                 goto corrupt;
 108         }
 109         /* Decode known protocol versions further without printing the header (the
 110          * type decoding is version-specific. */
 111         switch (version) {
 112         case OF_VER_1_0:
 113                 return of10_header_body_print(ndo, cp, ep, type, length, xid);
 114         default:
 115                 of_header_print(ndo, version, type, length, xid);
 116                 ND_TCHECK2(*cp, length - OF_HEADER_LEN);
 117                 return cp + length - OF_HEADER_LEN; /* done with current message */
 118         }
 119
 120 corrupt: /* fail current packet */
 121         ND_PRINT((ndo, "%s", cstr));
 122         ND_TCHECK2(*cp, ep - cp);
 123         return ep;
 124 trunc:
 125         ND_PRINT((ndo, "%s", tstr));
 126         return ep;
 127 }
 128
 129 /* Print a TCP segment worth of OpenFlow messages presuming the segment begins
 130  * on a message boundary. */
 131 void
 132 openflow_print(netdissect_options *ndo, const u_char *cp, const u_int len) {
 133         const u_char *ep = cp + len;
 134
 135         ND_PRINT((ndo, ": OpenFlow"));
 136         while (cp < ep)
 137                 cp = of_header_body_print(ndo, cp, ep);
 138 }