external/bsd/tcpdump/dist/print-geneve.c

   1 /*
   2  * Copyright (c) 2014 VMware, Inc. All Rights Reserved.
   3  *
   4  * Jesse Gross <jesse@nicira.com>
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that: (1) source code
   8  * distributions retain the above copyright notice and this paragraph
   9  * in its entirety, and (2) distributions including binary code include
  10  * the above copyright notice and this paragraph in its entirety in
  11  * the documentation or other materials provided with the distribution.
  12  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
  13  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
  14  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  15  * FOR A PARTICULAR PURPOSE.
  16  */
  17
  18 #define NETDISSECT_REWORKED
  19 #ifdef HAVE_CONFIG_H
  20 #include "config.h"
  21 #endif
  22
  23 #include <tcpdump-stdinc.h>
  24
  25 #include "interface.h"
  26 #include "extract.h"
  27 #include "ethertype.h"
  28
  29 /*
  30  * Geneve header, draft-gross-geneve-02
  31  *
  32  *    0                   1                   2                   3
  33  *    0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
  34  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  35  *    |Ver|  Opt Len  |O|C|    Rsvd.  |          Protocol Type        |
  36  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  37  *    |        Virtual Network Identifier (VNI)       |    Reserved   |
  38  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  39  *    |                    Variable Length Options                    |
  40  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  41  *
  42  * Options:
  43  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  44  *    |          Option Class         |      Type     |R|R|R| Length  |
  45  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  46  *    |                      Variable Option Data                     |
  47  *    +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
  48  */
  49
  50 #define VER_SHIFT 6
  51 #define HDR_OPTS_LEN_MASK 0x3F
  52
  53 #define FLAG_OAM      (1 << 7)
  54 #define FLAG_CRITICAL (1 << 6)
  55 #define FLAG_R1       (1 << 5)
  56 #define FLAG_R2       (1 << 4)
  57 #define FLAG_R3       (1 << 3)
  58 #define FLAG_R4       (1 << 2)
  59 #define FLAG_R5       (1 << 1)
  60 #define FLAG_R6       (1 << 0)
  61
  62 #define OPT_TYPE_CRITICAL (1 << 7)
  63 #define OPT_LEN_MASK 0x1F
  64
  65 static const struct tok geneve_flag_values[] = {
  66         { FLAG_OAM, "O" },
  67         { FLAG_CRITICAL, "C" },
  68         { FLAG_R1, "R1" },
  69         { FLAG_R2, "R2" },
  70         { FLAG_R3, "R3" },
  71         { FLAG_R4, "R4" },
  72         { FLAG_R5, "R5" },
  73         { FLAG_R6, "R6" },
  74         { 0, NULL }
  75 };
  76
  77 static const char *
  78 format_opt_class(uint16_t opt_class)
  79 {
  80     if (opt_class <= 0xff)
  81         return "Standard";
  82     else if (opt_class == 0xffff)
  83         return "Experimental";
  84     else
  85         return "Unknown";
  86 }
  87
  88 static void
  89 geneve_opts_print(netdissect_options *ndo, const u_char *bp, u_int len)
  90 {
  91     const char *sep = "";
  92
  93     while (len > 0) {
  94         uint16_t opt_class;
  95         uint8_t opt_type;
  96         uint8_t opt_len;
  97
  98         ND_PRINT((ndo, "%s", sep));
  99         sep = ", ";
 100
 101         opt_class = EXTRACT_16BITS(bp);
 102         opt_type = *(bp + 2);
 103         opt_len = 4 + ((*(bp + 3) & OPT_LEN_MASK) * 4);
 104
 105         ND_PRINT((ndo, "class %s (0x%x) type 0x%x%s len %u",
 106                   format_opt_class(opt_class), opt_class, opt_type,
 107                   opt_type & OPT_TYPE_CRITICAL ? "(C)" : "", opt_len));
 108
 109         if (opt_len > len) {
 110             ND_PRINT((ndo, " [bad length]"));
 111             return;
 112         }
 113
 114         if (ndo->ndo_vflag > 1 && opt_len > 4) {
 115             uint32_t *print_data = (uint32_t *)(bp + 4);
 116             int i;
 117
 118             ND_PRINT((ndo, " data"));
 119
 120             for (i = 4; i < opt_len; i += 4) {
 121                 ND_PRINT((ndo, " %08x", EXTRACT_32BITS(print_data)));
 122                 print_data++;
 123             }
 124         }
 125
 126         bp += opt_len;
 127         len -= opt_len;
 128     }
 129 }
 130
 131 void
 132 geneve_print(netdissect_options *ndo, const u_char *bp, u_int len)
 133 {
 134     uint8_t ver_opt;
 135     uint version;
 136     uint8_t flags;
 137     uint16_t prot;
 138     uint32_t vni;
 139     uint8_t reserved;
 140     u_int opts_len;
 141
 142     ND_PRINT((ndo, "Geneve"));
 143
 144     ND_TCHECK2(*bp, 8);
 145
 146     ver_opt = *bp;
 147     bp += 1;
 148     len -= 1;
 149
 150     version = ver_opt >> VER_SHIFT;
 151     if (version != 0) {
 152         ND_PRINT((ndo, " ERROR: unknown-version %u", version));
 153         return;
 154     }
 155
 156     flags = *bp;
 157     bp += 1;
 158     len -= 1;
 159
 160     prot = EXTRACT_16BITS(bp);
 161     bp += 2;
 162     len -= 2;
 163
 164     vni = EXTRACT_24BITS(bp);
 165     bp += 3;
 166     len -= 3;
 167
 168     reserved = *bp;
 169     bp += 1;
 170     len -= 1;
 171
 172     ND_PRINT((ndo, ", Flags [%s]",
 173               bittok2str_nosep(geneve_flag_values, "none", flags)));
 174     ND_PRINT((ndo, ", vni 0x%x", vni));
 175
 176     if (reserved)
 177         ND_PRINT((ndo, ", rsvd 0x%x", reserved));
 178
 179     if (ndo->ndo_eflag)
 180         ND_PRINT((ndo, ", proto %s (0x%04x)",
 181                   tok2str(ethertype_values, "unknown", prot), prot));
 182
 183     opts_len = (ver_opt & HDR_OPTS_LEN_MASK) * 4;
 184
 185     if (len < opts_len) {
 186         ND_PRINT((ndo, " truncated-geneve - %u bytes missing",
 187                   len - opts_len));
 188         return;
 189     }
 190
 191     ND_TCHECK2(*bp, opts_len);
 192
 193     if (opts_len > 0) {
 194         ND_PRINT((ndo, ", options ["));
 195
 196         if (ndo->ndo_vflag)
 197             geneve_opts_print(ndo, bp, opts_len);
 198         else
 199             ND_PRINT((ndo, "%u bytes", opts_len));
 200
 201         ND_PRINT((ndo, "]"));
 202     }
 203
 204     bp += opts_len;
 205     len -= opts_len;
 206
 207     if (ndo->ndo_vflag < 1)
 208         ND_PRINT((ndo, ": "));
 209     else
 210         ND_PRINT((ndo, "\n\t"));
 211
 212     if (ethertype_print(ndo, prot, bp, len, len) == 0) {
 213         if (prot == ETHERTYPE_TEB)
 214             ether_print(ndo, bp, len, len, NULL, NULL);
 215         else
 216             ND_PRINT((ndo, "geneve-proto-0x%x", prot));
 217     }
 218
 219     return;
 220
 221 trunc:
 222     ND_PRINT((ndo, " [|geneve]"));
 223 }