epan/dissectors/packet-pppoe.c

   1 /* packet-pppoe.c
   2  * Routines for PPP Over Ethernet (PPPoE) packet disassembly (RFC2516)
   3  * Up to date with http://www.iana.org/assignments/pppoe-parameters (2008-04-30)
   4  *
   5  * $Id$
   6  *
   7  * Wireshark - Network traffic analyzer
   8  * By Gerald Combs <gerald@wireshark.org>
   9  * Copyright 1998 Gerald Combs
  10  *
  11  * This program is free software; you can redistribute it and/or
  12  * modify it under the terms of the GNU General Public License
  13  * as published by the Free Software Foundation; either version 2
  14  * of the License, or (at your option) any later version.
  15  *
  16  * This program is distributed in the hope that it will be useful,
  17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19  * GNU General Public License for more details.
  20  *
  21  * You should have received a copy of the GNU General Public License
  22  * along with this program; if not, write to the Free Software
  23  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
  24  */
  25
  26 #ifdef HAVE_CONFIG_H
  27 # include "config.h"
  28 #endif
  29
  30 #include <glib.h>
  31 #include <epan/packet.h>
  32 #include <epan/strutil.h>
  33 #include <epan/etypes.h>
  34 #include <epan/prefs.h>
  35 #include <epan/expert.h>
  36 #include <epan/ppptypes.h>
  37
  38 static int proto_pppoed = -1;
  39
  40 /* Common to session and discovery protocols */
  41 static gint hf_pppoe_version = -1;
  42 static gint hf_pppoe_type = -1;
  43 static gint hf_pppoe_code = -1;
  44 static gint hf_pppoe_session_id = -1;
  45 static gint hf_pppoe_payload_length = -1;
  46
  47 /* Discovery protocol fields */
  48 static gint hf_pppoed_tags = -1;
  49 static gint hf_pppoed_tag = -1;
  50 static gint hf_pppoed_tag_length = -1;
  51 static gint hf_pppoed_tag_length_8 = -1;
  52 static gint hf_pppoed_tag_unknown_data = -1;
  53 static gint hf_pppoed_tag_service_name = -1;
  54 static gint hf_pppoed_tag_ac_name = -1;
  55 static gint hf_pppoed_tag_host_uniq = -1;
  56 static gint hf_pppoed_tag_ac_cookie = -1;
  57 static gint hf_pppoed_tag_vendor_id = -1;
  58 static gint hf_pppoed_tag_vendor_unspecified = -1;
  59 static gint hf_pppoed_tag_vspec_tags = -1;
  60 static gint hf_pppoed_tag_vspec_tag = -1;
  61 static gint hf_pppoed_tag_vspec_circuit_id = -1;
  62 static gint hf_pppoed_tag_vspec_remote_id = -1;
  63 static gint hf_pppoed_tag_vspec_act_data_rate_up = -1;
  64 static gint hf_pppoed_tag_vspec_act_data_rate_down = -1;
  65 static gint hf_pppoed_tag_vspec_min_data_rate_up = -1;
  66 static gint hf_pppoed_tag_vspec_min_data_rate_down = -1;
  67 static gint hf_pppoed_tag_vspec_attainable_data_rate_up = -1;
  68 static gint hf_pppoed_tag_vspec_attainable_data_rate_down = -1;
  69 static gint hf_pppoed_tag_vspec_max_data_rate_up = -1;
  70 static gint hf_pppoed_tag_vspec_max_data_rate_down = -1;
  71 static gint hf_pppoed_tag_vspec_min_data_rate_up_lp = -1;
  72 static gint hf_pppoed_tag_vspec_min_data_rate_down_lp = -1;
  73 static gint hf_pppoed_tag_vspec_max_int_delay_up = -1;
  74 static gint hf_pppoed_tag_vspec_act_int_delay_up = -1;
  75 static gint hf_pppoed_tag_vspec_max_int_delay_down = -1;
  76 static gint hf_pppoed_tag_vspec_act_int_delay_down = -1;
  77 static gint hf_pppoed_tag_vspec_access_loop_encapsulation = -1;
  78 static gint hf_pppoed_tag_vspec_access_loop_encap_data_link = -1;
  79 static gint hf_pppoed_tag_vspec_access_loop_encap_encap_1 = -1;
  80 static gint hf_pppoed_tag_vspec_access_loop_encap_encap_2 = -1;
  81 static gint hf_pppoed_tag_credits = -1;
  82 static gint hf_pppoed_tag_credits_fcn = -1;
  83 static gint hf_pppoed_tag_credits_bcn = -1;
  84 static gint hf_pppoed_tag_metrics = -1;
  85 static gint hf_pppoed_tag_metrics_r = -1;
  86 static gint hf_pppoed_tag_metrics_rlq = -1;
  87 static gint hf_pppoed_tag_metrics_resource = -1;
  88 static gint hf_pppoed_tag_metrics_latency = -1;
  89 static gint hf_pppoed_tag_metrics_curr_drate = -1;
  90 static gint hf_pppoed_tag_metrics_max_drate = -1;
  91 static gint hf_pppoed_tag_mdr_units = -1;
  92 static gint hf_pppoed_tag_cdr_units = -1;
  93 static gint hf_pppoed_tag_seq_num = -1;
  94 static gint hf_pppoed_tag_cred_scale = -1;
  95 static gint hf_pppoed_tag_relay_session_id = -1;
  96 static gint hf_pppoed_tag_hurl = -1;
  97 static gint hf_pppoed_tag_motm = -1;
  98 static gint hf_pppoed_tag_max_payload = -1;
  99 static gint hf_pppoed_tag_ip_route_add = -1;
 100 static gint hf_pppoed_tag_service_name_error = -1;
 101 static gint hf_pppoed_tag_ac_system_error = -1;
 102 static gint hf_pppoed_tag_generic_error = -1;
 103
 104 /* Session protocol fields */
 105 static gint hf_pppoes_tags = -1;
 106 static gint hf_pppoes_tag = -1;
 107 static gint hf_pppoes_tag_credits = -1;
 108 static gint hf_pppoes_tag_credits_fcn = -1;
 109 static gint hf_pppoes_tag_credits_bcn = -1;
 110
 111 /* Session protocol fields */
 112
 113 static gint ett_pppoed = -1;
 114 static gint ett_pppoed_tags = -1;
 115 static gint ett_pppoed_tag_vspec_dslf_access_loop_encaps = -1;
 116
 117 static int proto_pppoes = -1;
 118
 119 static gint ett_pppoes = -1;
 120 static gint ett_pppoes_tags = -1;
 121
 122 /* PPPoE parent fields */
 123
 124 static int proto_pppoe = -1;
 125 static gint ett_pppoe = -1;
 126
 127
 128 /* Handle for calling for ppp dissector to handle session data */
 129 static dissector_handle_t ppp_handle;
 130
 131
 132 /* Preference for showing discovery tag values and lengths */
 133 static gboolean global_pppoe_show_tags_and_lengths = FALSE;
 134
 135
 136 #define PPPOE_CODE_SESSION    0x00
 137 #define PPPOE_CODE_PADO       0x07
 138 #define PPPOE_CODE_PADI       0x09
 139 #define PPPOE_CODE_PADG       0x0a
 140 #define PPPOE_CODE_PADC       0x0b
 141 #define PPPOE_CODE_PADQ       0x0c
 142 #define PPPOE_CODE_PADR       0x19
 143 #define PPPOE_CODE_PADS       0x65
 144 #define PPPOE_CODE_PADT       0xa7
 145 #define PPPOE_CODE_PADM       0xd3
 146 #define PPPOE_CODE_PADN       0xd4
 147
 148 #define PPPOE_TAG_EOL         0x0000
 149 #define PPPOE_TAG_SVC_NAME    0x0101
 150 #define PPPOE_TAG_AC_NAME     0x0102
 151 #define PPPOE_TAG_HOST_UNIQ   0x0103
 152 #define PPPOE_TAG_AC_COOKIE   0x0104
 153 #define PPPOE_TAG_VENDOR      0x0105
 154 #define PPPOE_TAG_CREDITS     0x0106
 155 #define PPPOE_TAG_METRICS     0x0107
 156 #define PPPOE_TAG_SEQ_NUM     0x0108
 157 #define PPPOE_TAG_CRED_SCALE  0x0109
 158 #define PPPOE_TAG_RELAY_ID    0x0110
 159 #define PPPOE_TAG_HURL        0x0111
 160 #define PPPOE_TAG_MOTM        0x0112
 161 #define PPPOE_TAG_MAX_PAYLD   0x0120
 162 #define PPPOE_TAG_IP_RT_ADD   0x0121
 163 #define PPPOE_TAG_SVC_ERR     0x0201
 164 #define PPPOE_TAG_AC_ERR      0x0202
 165 #define PPPOE_TAG_GENERIC_ERR 0x0203
 166
 167 #define PPPOE_VENDOR_ID_DSLF  3561
 168
 169 #define PPPOE_TAG_VSPEC_DSLF_CIRCUIT_ID                0x01
 170 #define PPPOE_TAG_VSPEC_DSLF_REMOTE_ID                 0x02
 171 #define PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_UP          0x81
 172 #define PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_DOWN        0x82
 173 #define PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP          0x83
 174 #define PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN        0x84
 175 #define PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_UP   0x85
 176 #define PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_DOWN 0x86
 177 #define PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_UP          0x87
 178 #define PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_DOWN        0x88
 179 #define PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP_LP       0x89
 180 #define PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN_LP     0x8a
 181 #define PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_UP          0x8b
 182 #define PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_UP          0x8c
 183 #define PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_DOWN        0x8d
 184 #define PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_DOWN        0x8e
 185 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAPSULATION 0x90
 186
 187 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_DATA_LINK_ATM 0x00
 188 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_DATA_LINK_ETH 0x01
 189
 190 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_NA               0x00
 191 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_UNTAGGED_ETH     0x01
 192 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_SINLE_TAGGED_ETH 0x02
 193
 194 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_NA                             0x00
 195 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_PPPOA_LLC                      0x01
 196 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_PPPOA_NULL                     0x02
 197 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_IPOA_LLC                       0x03
 198 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_IPOA_NULL                      0x04
 199 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_LLC_WITH_FCS     0x05
 200 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_LLC_WITHOUT_FCS  0x06
 201 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_NULL_WITH_FCS    0x07
 202 #define PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_NULL_WITHOUT_FCS 0x08
 203
 204 #define PPPOE_CDR_MASK        0x06
 205 #define PPPOE_MDR_MASK        0x18
 206 #define PPPOE_RCV_ONLY_MASK   0x01
 207
 208 #define PPPOE_SCALE_KBPS      0x00
 209 #define PPPOE_SCALE_MBPS      0x01
 210 #define PPPOE_SCALE_GBPS      0x02
 211 #define PPPOE_SCALE_TBPS      0x03
 212
 213
 214 static const value_string code_vals[] = {
 215                 {PPPOE_CODE_SESSION, "Session Data"                             },
 216                 {PPPOE_CODE_PADO, "Active Discovery Offer (PADO)"               },
 217                 {PPPOE_CODE_PADI, "Active Discovery Initiation (PADI)"          },
 218                 {PPPOE_CODE_PADG, "Active Discovery Session-Grant (PADG)"       },
 219                 {PPPOE_CODE_PADC, "Active Discovery Session-Credit Resp.(PADC)" },
 220                 {PPPOE_CODE_PADQ, "Active Discovery Quality (PADQ)"             },
 221                 {PPPOE_CODE_PADR, "Active Discovery Request (PADR)"             },
 222                 {PPPOE_CODE_PADS, "Active Discovery Session-confirmation (PADS)"},
 223                 {PPPOE_CODE_PADT, "Active Discovery Terminate (PADT)"           },
 224                 {PPPOE_CODE_PADM, "Active Discovery Message (PADM)"             },
 225                 {PPPOE_CODE_PADN, "Active Discovery Network (PADN)"             },
 226                 {0,               NULL                                          }
 227 };
 228
 229
 230 static const value_string tag_vals[] = {
 231                 {PPPOE_TAG_EOL,        "End-Of-List"       },
 232                 {PPPOE_TAG_SVC_NAME,   "Service-Name"      },
 233                 {PPPOE_TAG_AC_NAME,    "AC-Name"           },
 234                 {PPPOE_TAG_HOST_UNIQ,  "Host-Uniq"         },
 235                 {PPPOE_TAG_AC_COOKIE,  "AC-Cookie"         },
 236                 {PPPOE_TAG_VENDOR,     "Vendor-Specific"   },
 237                 {PPPOE_TAG_CREDITS,    "Credits"           },
 238                 {PPPOE_TAG_METRICS,    "Metrics"           },
 239                 {PPPOE_TAG_SEQ_NUM,    "Sequence Number"    },
 240                 {PPPOE_TAG_CRED_SCALE, "Credit Scale Factor"},
 241                 {PPPOE_TAG_RELAY_ID,   "Relay-Session-Id"  },
 242                 {PPPOE_TAG_HURL,       "HURL"              },
 243                 {PPPOE_TAG_MOTM,       "MOTM"              },
 244                 {PPPOE_TAG_MAX_PAYLD,  "PPP-Max-Payload"   },
 245                 {PPPOE_TAG_IP_RT_ADD,  "IP Route Add"      },
 246                 {PPPOE_TAG_SVC_ERR,    "Service-Name-Error"},
 247                 {PPPOE_TAG_AC_ERR,     "AC-System-Error"   },
 248                 {PPPOE_TAG_GENERIC_ERR,"Generic-Error"     },
 249                 {0,                    NULL                }
 250 };
 251
 252 static const value_string vspec_tag_vals[] = {
 253                 {PPPOE_TAG_VSPEC_DSLF_CIRCUIT_ID,                "Circuit-ID"                    },
 254                 {PPPOE_TAG_VSPEC_DSLF_REMOTE_ID,                 "Remote-ID"                     },
 255                 {PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_UP,          "Actual-Data-Rate-Up"           },
 256                 {PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_DOWN,        "Actual-Data-Rate-Down"         },
 257                 {PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP,          "Min-Data-Rate-Up"              },
 258                 {PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN,        "Min-Data-Rate-Down"            },
 259                 {PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_UP,   "Attainable-Data-Rate-Up"       },
 260                 {PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_DOWN, "Attainable-Data-Rate-Down"     },
 261                 {PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_UP,          "Max-Data-Rate-Up"              },
 262                 {PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_DOWN,        "Max-Data-Rate-Down"            },
 263                 {PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP_LP,       "Min-Data-Rate-Up-Low-Power"    },
 264                 {PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN_LP,     "Min-Data-Rate-Down-Low-Power"  },
 265                 {PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_UP,          "Max-Interleaving-Delay-Up"     },
 266                 {PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_UP,          "Actual-Interleaving-Delay-Up"  },
 267                 {PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_DOWN,        "Max-Interleaving-Delay-Down"   },
 268                 {PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_DOWN,        "Actual-Interleaving-Delay-Down"},
 269                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAPSULATION, "Access-Loop-Encapsulation"     },
 270                 {0,                                              NULL                            }
 271 };
 272
 273 static const value_string vspec_tag_dslf_access_loop_encap_data_link_vals[] = {
 274                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_DATA_LINK_ATM, "ATM AAL5"},
 275                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_DATA_LINK_ETH, "Ethernet"},
 276                 {0,                                                     NULL     }
 277 };
 278
 279 static const value_string vspec_tag_dslf_access_loop_encap_encap_1_vals[] = {
 280                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_NA,               "NA"                    },
 281                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_UNTAGGED_ETH,     "Untagged Ethernet"     },
 282                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_1_SINLE_TAGGED_ETH, "Single-tagged Ethernet"},
 283                 {0,                                                     NULL                               }
 284 };
 285
 286 static const value_string vspec_tag_dslf_access_loop_encap_encap_2_vals[] = {
 287                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_NA,                            "NA"                             },
 288                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_PPPOA_LLC,                     "PPPoA LLC"                      },
 289                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_PPPOA_NULL,                    "PPPoA Null"                     },
 290                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_IPOA_LLC,                      "IPoA LLC"                       },
 291                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_IPOA_NULL,                     "IPoA Null"                      },
 292                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_LLC_WITH_FCS,    "Ethernet over AAL5 LLC w FCS"   },
 293                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_LLC_WITHOUT_FCS, "Ethernet over AAL5 LLC w/o FCS" },
 294                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_NULL_WITH_FCS,   "Ethernet over AAL5 Null w FCS"  },
 295                 {PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAP_ENCAPS_2_ETH_OVER_AAL5_NULL_WITHOUT_FCS,"Ethernet over AAL5 Null w/o FCS"},
 296                 {0,                                                     NULL                               }
 297 };
 298
 299 const value_string datarate_scale_vals[] = {
 300                 {PPPOE_SCALE_KBPS,      "kilobits per second"},
 301                 {PPPOE_SCALE_MBPS,      "megabits per second"},
 302                 {PPPOE_SCALE_GBPS,      "gigabits per second"},
 303                 {PPPOE_SCALE_TBPS,      "terabits per second"},
 304                 {0,                     NULL                 }
 305 };
 306
 307
 308 #define CASE_VSPEC_DSLF_TAG(tag_name, relation, length, hf_var) case tag_name: \
 309                 if (!(poe_tag_length relation length)) { \
 310                         expert_add_info_format(pinfo, pppoe_tree, PI_MALFORMED, PI_WARN, "%s: Wrong length: %u (expected %s %d)", \
 311                                         val_to_str(poe_tag, vspec_tag_vals, "Unknown"), poe_tag_length, #relation, length); \
 312                 } else { \
 313                         proto_tree_add_item(pppoe_tree, hf_var, tvb, \
 314                                 tagstart+2, poe_tag_length, FALSE); \
 315                 } \
 316         break;
 317
 318 /* Dissect Vendor-Specific Tags introduced by the DSLF */
 319 static void
 320 dissect_pppoe_subtags_dslf(tvbuff_t *tvb, packet_info *pinfo _U_, int offset, proto_tree *tree,
 321                    int payload_length)
 322 {
 323         guint8 poe_tag;
 324         guint8 poe_tag_length;
 325         int tagstart;
 326
 327         proto_tree  *pppoe_tree, *ti, *encaps_tree;
 328
 329         /* Start Decoding Here. */
 330         if (tree)
 331         {
 332                 /* Create tags subtree */
 333                 ti = proto_tree_add_item(tree, hf_pppoed_tag_vspec_tags, tvb, offset, payload_length, FALSE);
 334                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed_tags);
 335
 336                 tagstart = offset;
 337
 338                 /* Loop until all data seen or End-Of-List tag found */
 339                 while (tagstart <= offset + payload_length-2)
 340                 {
 341                         poe_tag = tvb_get_guint8(tvb, tagstart);
 342                         poe_tag_length = tvb_get_guint8(tvb, tagstart + 1);
 343
 344                         /* Tag value and data length */
 345                         if (global_pppoe_show_tags_and_lengths)
 346                         {
 347                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vspec_tag, tvb, tagstart, 1, FALSE);
 348                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length_8, tvb, tagstart+1, 1, FALSE);
 349                         }
 350
 351                         /* Show tag data */
 352                         switch (poe_tag)
 353                         {
 354                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_CIRCUIT_ID, <=, 63,
 355                                                 hf_pppoed_tag_vspec_circuit_id)
 356                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_REMOTE_ID, <=, 63,
 357                                                 hf_pppoed_tag_vspec_remote_id)
 358                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_UP, ==, 4,
 359                                                 hf_pppoed_tag_vspec_act_data_rate_up)
 360                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ACT_DATA_RATE_DOWN, ==, 4,
 361                                                 hf_pppoed_tag_vspec_act_data_rate_down)
 362                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP, ==, 4,
 363                                                 hf_pppoed_tag_vspec_min_data_rate_up)
 364                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN, ==, 4,
 365                                                 hf_pppoed_tag_vspec_min_data_rate_down)
 366                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_UP, ==, 4,
 367                                                 hf_pppoed_tag_vspec_attainable_data_rate_up)
 368                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ATTAINABLE_DATA_RATE_DOWN, ==, 4,
 369                                                 hf_pppoed_tag_vspec_attainable_data_rate_down)
 370                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_UP, ==, 4,
 371                                                 hf_pppoed_tag_vspec_max_data_rate_up)
 372                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MAX_DATA_RATE_DOWN, ==, 4,
 373                                                 hf_pppoed_tag_vspec_max_data_rate_down)
 374                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_UP_LP, ==, 4,
 375                                                 hf_pppoed_tag_vspec_min_data_rate_up_lp)
 376                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MIN_DATA_RATE_DOWN_LP, ==, 4,
 377                                                 hf_pppoed_tag_vspec_min_data_rate_down_lp)
 378                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_UP, ==, 4,
 379                                                 hf_pppoed_tag_vspec_max_int_delay_up)
 380                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_UP, ==, 4,
 381                                                 hf_pppoed_tag_vspec_act_int_delay_up)
 382                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_MAX_INT_DELAY_DOWN, ==, 4,
 383                                                 hf_pppoed_tag_vspec_max_int_delay_down)
 384                                 CASE_VSPEC_DSLF_TAG(PPPOE_TAG_VSPEC_DSLF_ACT_INT_DELAY_DOWN, ==, 4,
 385                                                 hf_pppoed_tag_vspec_act_int_delay_down)
 386                                 case PPPOE_TAG_VSPEC_DSLF_ACCESS_LOOP_ENCAPSULATION:
 387                                         ti = proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vspec_access_loop_encapsulation, tvb,
 388                                                         tagstart+2, 3, FALSE);
 389                                         if (poe_tag_length != 3) {
 390                                                 expert_add_info_format(pinfo, ti, PI_MALFORMED, PI_WARN,
 391                                                                 "%s: Wrong length: %u (expected 3)",
 392                                                                 val_to_str(poe_tag, vspec_tag_vals, "Unknown"), poe_tag_length);
 393                                         }
 394                                         encaps_tree = proto_item_add_subtree(ti, ett_pppoed_tag_vspec_dslf_access_loop_encaps);
 395                                         proto_tree_add_item(encaps_tree, hf_pppoed_tag_vspec_access_loop_encap_data_link,
 396                                                         tvb, tagstart+2, 1, FALSE);
 397                                         proto_tree_add_item(encaps_tree, hf_pppoed_tag_vspec_access_loop_encap_encap_1,
 398                                                         tvb, tagstart+3, 1, FALSE);
 399                                         proto_tree_add_item(encaps_tree, hf_pppoed_tag_vspec_access_loop_encap_encap_2,
 400                                                         tvb, tagstart+4, 1, FALSE);
 401
 402                                         break;
 403                                 default:
 404                                         if (poe_tag_length > 0 )
 405                                         {
 406                                                 /* Presumably unknown tag;
 407                                                    show tag value if we didn't do it above */
 408                                                 if (!global_pppoe_show_tags_and_lengths)
 409                                                 {
 410                                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag, tvb, tagstart, 1, FALSE);
 411                                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length_8, tvb, tagstart+1, 1, FALSE);
 412                                                 }
 413                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_unknown_data, tvb,
 414                                                                 tagstart+1, poe_tag_length, FALSE);
 415                                         }
 416                         }
 417
 418                         tagstart += (2 + poe_tag_length);
 419                 }
 420         }
 421 }
 422
 423
 424 /* Dissect discovery protocol tags */
 425 static void
 426 dissect_pppoe_tags(tvbuff_t *tvb, packet_info *pinfo, int offset, proto_tree *tree,
 427                    int payload_length)
 428 {
 429         guint16 poe_tag;
 430         guint16 poe_tag_length;
 431         int tagstart;
 432         guint16 poe_rsv = 0;
 433
 434         proto_tree  *pppoe_tree;
 435         proto_item  *ti;
 436         proto_item  *pppoe_tree_tag_length_item = NULL;
 437         proto_item  *item;
 438
 439         /* Start Decoding Here. */
 440         if (tree)
 441         {
 442                 /* Create tags subtree */
 443                 ti = proto_tree_add_item(tree, hf_pppoed_tags, tvb, offset, payload_length-6, FALSE);
 444                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed_tags);
 445
 446                 tagstart = offset;
 447
 448                 /* Loop until all data seen or End-Of-List tag found */
 449                 while (tagstart <= payload_length-2)
 450                 {
 451                         poe_tag = tvb_get_ntohs(tvb, tagstart);
 452                         poe_tag_length = tvb_get_ntohs(tvb, tagstart + 2);
 453
 454                         /* Tag value and data length */
 455                         if (global_pppoe_show_tags_and_lengths)
 456                         {
 457                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag, tvb, tagstart, 2, FALSE);
 458                                 pppoe_tree_tag_length_item =
 459                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length, tvb, tagstart+2, 2, FALSE);
 460                         }
 461
 462                         /* Show tag data */
 463                         switch (poe_tag)
 464                         {
 465                                 case PPPOE_TAG_SVC_NAME:
 466                                         if (poe_tag_length > 0)
 467                                         {
 468                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_service_name, tvb,
 469                                                                     tagstart+4, poe_tag_length, FALSE);
 470                                         }
 471                                         break;
 472                                 case PPPOE_TAG_AC_NAME:
 473                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_name, tvb,
 474                                                             tagstart+4, poe_tag_length, FALSE);
 475                                         /* Show AC-Name in info column */
 476                                         if (check_col(pinfo->cinfo, COL_INFO))
 477                                         {
 478                                                 col_append_fstr(pinfo->cinfo, COL_INFO, " AC-Name='%s'",
 479                                                                tvb_get_ephemeral_string(tvb, tagstart+4, poe_tag_length));
 480                                         }
 481                                         break;
 482                                 case PPPOE_TAG_HOST_UNIQ:
 483                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_host_uniq, tvb,
 484                                                             tagstart+4, poe_tag_length, FALSE);
 485                                         break;
 486                                 case PPPOE_TAG_AC_COOKIE:
 487                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_cookie, tvb,
 488                                                             tagstart+4, poe_tag_length, FALSE);
 489                                         break;
 490                                 case PPPOE_TAG_VENDOR:
 491                                         if (poe_tag_length >= 4)
 492                                         {
 493                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vendor_id, tvb,
 494                                                                                         tagstart+4, 4, FALSE);
 495                                         }
 496                                         if (poe_tag_length > 4)
 497                                         {
 498                                                 guint32 vendor_id = tvb_get_ntohl(tvb, tagstart+4);
 499                                                 switch (vendor_id)
 500                                                 {
 501                                                         case PPPOE_VENDOR_ID_DSLF:
 502                                                                 dissect_pppoe_subtags_dslf(tvb,pinfo,tagstart+4+4,pppoe_tree,poe_tag_length-4);
 503                                                                 break;
 504                                                         default:
 505                                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_vendor_unspecified, tvb,
 506                                                                                     tagstart+4+4, poe_tag_length-4, FALSE);
 507
 508                                                 }
 509                                         }
 510                                         break;
 511                                 case PPPOE_TAG_CREDITS:
 512                                         if (poe_tag_length == 4)
 513                                         {
 514                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits_fcn, tvb,
 515                                                                     tagstart+4, 2, FALSE);
 516                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits_bcn, tvb,
 517                                                                     tagstart+6, 2, FALSE);
 518                                         } else {
 519                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits, tvb,
 520                                                                     tagstart+4, poe_tag_length, FALSE);
 521                                         }
 522                                         break;
 523                                 case PPPOE_TAG_METRICS:
 524                                         if (poe_tag_length == 10)
 525                                         {
 526                                                 poe_rsv = tvb_get_ntohs(tvb, tagstart+4);
 527
 528                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_mdr_units, tvb,
 529                                                                     tagstart+4, 2, FALSE);
 530                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_cdr_units, tvb,
 531                                                                     tagstart+4, 2, FALSE);
 532                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_r, tvb,
 533                                                                     tagstart+4, 2, FALSE);
 534                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_rlq, tvb,
 535                                                                     tagstart+6, 1, FALSE);
 536                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_resource, tvb,
 537                                                                     tagstart+7, 1, FALSE);
 538                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_latency, tvb,
 539                                                                     tagstart+8, 2, FALSE);
 540
 541                                                 /* CDR */
 542                                                 ti = proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_curr_drate, tvb,
 543                                                                          tagstart+10, 2, FALSE);
 544
 545                                                 switch ((poe_rsv & PPPOE_CDR_MASK) >> 1)
 546                                                 {
 547                                                 case (PPPOE_SCALE_KBPS):
 548                                                     proto_item_append_text(ti, " kbps");
 549                                                     break;
 550                                                 case (PPPOE_SCALE_MBPS):
 551                                                     proto_item_append_text(ti, " mbps");
 552                                                     break;
 553                                                 case (PPPOE_SCALE_GBPS):
 554                                                     proto_item_append_text(ti, " gbps");
 555                                                     break;
 556                                                 case (PPPOE_SCALE_TBPS):
 557                                                     proto_item_append_text(ti, " tbps");
 558                                                     break;
 559                                                 }
 560
 561                                                 /* MDR */
 562                                                 ti = proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics_max_drate, tvb,
 563                                                                     tagstart+12, 2, FALSE);
 564
 565                                                 switch ((poe_rsv & PPPOE_MDR_MASK) >> 3)
 566                                                 {
 567                                                 case (PPPOE_SCALE_KBPS):
 568                                                     proto_item_append_text(ti, " kbps");
 569                                                     break;
 570                                                 case (PPPOE_SCALE_MBPS):
 571                                                     proto_item_append_text(ti, " mbps");
 572                                                     break;
 573                                                 case (PPPOE_SCALE_GBPS):
 574                                                     proto_item_append_text(ti, " gbps");
 575                                                     break;
 576                                                 case (PPPOE_SCALE_TBPS):
 577                                                     proto_item_append_text(ti, " tbps");
 578                                                     break;
 579                                                 }
 580
 581                                         } else {
 582                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_metrics, tvb,
 583                                                                     tagstart+4, poe_tag_length, FALSE);
 584                                         }
 585                                         break;
 586                                 case PPPOE_TAG_SEQ_NUM:
 587                                         if (poe_tag_length == 2) {
 588                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_seq_num, tvb,
 589                                                                     tagstart+4, poe_tag_length, FALSE);
 590                                         } else {
 591                                                 if (global_pppoe_show_tags_and_lengths) {
 592                                                         proto_item_append_text(pppoe_tree_tag_length_item, " [Wrong: should be 2]");
 593                                                         item = pppoe_tree_tag_length_item;
 594                                                 } else {
 595                                                         item = proto_tree_add_text(pppoe_tree, tvb, tagstart+4, poe_tag_length,
 596                                                             "%s: Wrong length: %u (expected 2)",
 597                                                             proto_registrar_get_name(hf_pppoed_tag_seq_num),
 598                                                             poe_tag_length);
 599                                                 }
 600                                                 expert_add_info_format(pinfo, item, PI_MALFORMED, PI_WARN,
 601                                                                        "Sequence Number tag: Wrong length: %u (expected 2)",
 602                                                                        poe_tag_length);
 603                                         }
 604                                         break;
 605                                 case PPPOE_TAG_CRED_SCALE:
 606                                         if (poe_tag_length == 2) {
 607                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_cred_scale, tvb,
 608                                                                     tagstart+4, poe_tag_length, FALSE);
 609                                         } else {
 610                                                 if (global_pppoe_show_tags_and_lengths) {
 611                                                         proto_item_append_text(pppoe_tree_tag_length_item, " [Wrong: should be 2]");
 612                                                         item = pppoe_tree_tag_length_item;
 613                                                 } else {
 614                                                         item = proto_tree_add_text(pppoe_tree, tvb, tagstart+4, poe_tag_length,
 615                                                             "%s: Wrong length: %u (expected 2)",
 616                                                             proto_registrar_get_name(hf_pppoed_tag_cred_scale),
 617                                                             poe_tag_length);
 618                                                 }
 619                                                 expert_add_info_format(pinfo, item, PI_MALFORMED, PI_WARN,
 620                                                                        "Credit Scale Factor tag: Wrong length: %u (expected 2)",
 621                                                                        poe_tag_length);
 622                                         }
 623                                         break;
 624                                 case PPPOE_TAG_RELAY_ID:
 625                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_relay_session_id, tvb,
 626                                                             tagstart+4, poe_tag_length, FALSE);
 627                                         break;
 628                                 case PPPOE_TAG_HURL:
 629                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_hurl, tvb,
 630                                                             tagstart+4, poe_tag_length, FALSE);
 631                                         break;
 632                                 case PPPOE_TAG_MOTM:
 633                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_motm, tvb,
 634                                                             tagstart+4, poe_tag_length, FALSE);
 635                                         break;
 636                                 case PPPOE_TAG_MAX_PAYLD:
 637                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_max_payload, tvb,
 638                                                             tagstart+4, poe_tag_length, FALSE);
 639                                         break;
 640                                 case PPPOE_TAG_IP_RT_ADD:
 641                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ip_route_add, tvb,
 642                                                             tagstart+4, poe_tag_length, FALSE);
 643                                         break;
 644
 645                                 /* These error tag values should be interpreted as a utf-8 unterminated
 646                                    strings. */
 647                                 case PPPOE_TAG_SVC_ERR:
 648                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_service_name_error, tvb,
 649                                                             tagstart+4, poe_tag_length, FALSE);
 650                                         break;
 651                                 case PPPOE_TAG_AC_ERR:
 652                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_ac_system_error, tvb,
 653                                                             tagstart+4, poe_tag_length, FALSE);
 654                                         break;
 655                                 case PPPOE_TAG_GENERIC_ERR:
 656                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_generic_error, tvb,
 657                                                             tagstart+4, poe_tag_length, FALSE);
 658                                         break;
 659
 660                                 /* Get out if see end-of-list tag */
 661                                 case PPPOE_TAG_EOL:
 662                                         return;
 663
 664                                 default:
 665                                         if (poe_tag_length > 0 )
 666                                         {
 667                                                 /* Presumably unknown tag;
 668                                                    show tag value if we didn't
 669                                                    do it above */
 670                                                 if (!global_pppoe_show_tags_and_lengths)
 671                                                 {
 672                                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag, tvb, tagstart, 2, FALSE);
 673                                                         proto_tree_add_item(pppoe_tree, hf_pppoed_tag_length, tvb, tagstart+2, 2, FALSE);
 674                                                 }
 675                                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_unknown_data, tvb,
 676                                                                 tagstart+2, poe_tag_length, FALSE);
 677                                         }
 678                         }
 679
 680                         tagstart += (4 + poe_tag_length);
 681                 }
 682         }
 683 }
 684
 685
 686 /* Discovery protocol, i.e. PPP session not yet established */
 687 static void dissect_pppoed(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
 688 {
 689         guint8  pppoe_code;
 690         guint16 reported_payload_length;
 691
 692         proto_tree  *pppoe_tree = NULL;
 693         proto_item  *ti;
 694
 695         col_set_str(pinfo->cinfo, COL_PROTOCOL, "PPPoED");
 696         col_clear(pinfo->cinfo, COL_INFO);
 697
 698         /* Start Decoding Here. */
 699         pppoe_code = tvb_get_guint8(tvb, 1);
 700
 701         if (check_col(pinfo->cinfo, COL_INFO))
 702         {
 703                 col_append_str(pinfo->cinfo, COL_INFO, val_to_str(pppoe_code, code_vals, "Unknown"));
 704         }
 705
 706         /* Read length of payload */
 707         reported_payload_length = tvb_get_ntohs(tvb, 4);
 708
 709         if (tree)
 710         {
 711                 ti = proto_tree_add_item(tree, proto_pppoed, tvb, 0, reported_payload_length+6, FALSE);
 712                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
 713
 714                 /* Dissect fixed fields */
 715                 proto_tree_add_item(pppoe_tree, hf_pppoe_version, tvb, 0, 1, FALSE);
 716                 proto_tree_add_item(pppoe_tree, hf_pppoe_type, tvb, 0, 1, FALSE);
 717                 proto_tree_add_item(pppoe_tree, hf_pppoe_code, tvb, 1, 1, FALSE);
 718                 proto_tree_add_item(pppoe_tree, hf_pppoe_session_id, tvb, 2, 2, FALSE);
 719                 proto_tree_add_item(pppoe_tree, hf_pppoe_payload_length, tvb, 4, 2, FALSE);
 720         }
 721
 722         /* Now dissect any tags */
 723         if (reported_payload_length > 0)
 724         {
 725                 dissect_pppoe_tags(tvb, pinfo, 6, pppoe_tree, 6+reported_payload_length);
 726         }
 727
 728 }
 729
 730 void proto_register_pppoed(void)
 731 {
 732         static hf_register_info hf[] =
 733         {
 734                 /* Discovery tag fields */
 735                 { &hf_pppoed_tags,
 736                         { "PPPoE Tags", "pppoed.tags", FT_NONE, BASE_NONE,
 737                                  NULL, 0x0, NULL, HFILL
 738                         }
 739                 },
 740                 { &hf_pppoed_tag,
 741                         { "Tag", "pppoed.tag", FT_UINT16, BASE_HEX,
 742                                  VALS(tag_vals), 0x0, NULL, HFILL
 743                         }
 744                 },
 745                 { &hf_pppoed_tag_length,
 746                         { "Tag Length", "pppoed.tag_length", FT_UINT16, BASE_DEC,
 747                                  NULL, 0x0, NULL, HFILL
 748                         }
 749                 },
 750                 { &hf_pppoed_tag_length_8,
 751                         { "Tag Length", "pppoed.tag_length_8", FT_UINT8, BASE_DEC,
 752                                  NULL, 0x0, NULL, HFILL
 753                         }
 754                 },
 755                 { &hf_pppoed_tag_unknown_data,
 756                         { "Unknown Data", "pppoed.tag.unknown_data", FT_BYTES, BASE_NONE,
 757                                  NULL, 0x0, NULL, HFILL
 758                         }
 759                 },
 760                 { &hf_pppoed_tag_service_name,
 761                         { "Service-Name", "pppoed.tags.service_name", FT_STRING, BASE_NONE,
 762                                  NULL, 0x0, NULL, HFILL
 763                         }
 764                 },
 765                 { &hf_pppoed_tag_ac_name,
 766                         { "AC-Name", "pppoed.tags.ac_name", FT_STRING, BASE_NONE,
 767                                  NULL, 0x0, NULL, HFILL
 768                         }
 769                 },
 770                 { &hf_pppoed_tag_host_uniq,
 771                         { "Host-Uniq", "pppoed.tags.host_uniq", FT_BYTES, BASE_NONE,
 772                                  NULL, 0x0, NULL, HFILL
 773                         }
 774                 },
 775                 { &hf_pppoed_tag_ac_cookie,
 776                         { "AC-Cookie", "pppoed.tags.ac_cookie", FT_BYTES, BASE_NONE,
 777                                  NULL, 0x0, NULL, HFILL
 778                         }
 779                 },
 780                 { &hf_pppoed_tag_vendor_id,
 781                         { "Vendor id", "pppoed.tags.vendor_id", FT_UINT32, BASE_DEC,
 782                                  NULL, 0x0, NULL, HFILL
 783                         }
 784                 },
 785                 { &hf_pppoed_tag_vendor_unspecified,
 786                         { "Vendor unspecified", "pppoed.tags.vendor_unspecified", FT_BYTES, BASE_NONE,
 787                                  NULL, 0x0, NULL, HFILL
 788                         }
 789                 },
 790                 { &hf_pppoed_tag_vspec_tags,
 791                         { "Vendor Specific PPPoE Tags", "pppoed.tags.vendorspecific.tags", FT_NONE, BASE_NONE,
 792                                  NULL, 0x0, NULL, HFILL
 793                         }
 794                 },
 795                 { &hf_pppoed_tag_vspec_tag,
 796                         { "Tag", "pppoed.tags.vendorspecific.tag", FT_UINT8, BASE_HEX,
 797                                  VALS(vspec_tag_vals), 0x0, NULL, HFILL
 798                         }
 799                 },
 800                 { &hf_pppoed_tag_vspec_circuit_id,
 801                         { "Circuit ID", "pppoed.tags.circuit_id", FT_STRING, BASE_NONE,
 802                                  NULL, 0x0, NULL, HFILL
 803                         }
 804                 },
 805                 { &hf_pppoed_tag_vspec_remote_id,
 806                         { "Remote ID", "pppoed.tags.remote_id", FT_STRING, BASE_NONE,
 807                                  NULL, 0x0, NULL, HFILL
 808                         }
 809                 },
 810                 { &hf_pppoed_tag_vspec_act_data_rate_up,
 811                         { "Actual Data Rate Upstream", "pppoed.tags.act_data_rate_up", FT_UINT32, BASE_DEC,
 812                                  NULL, 0x0, NULL, HFILL
 813                         }
 814                 },
 815                 { &hf_pppoed_tag_vspec_act_data_rate_down,
 816                         { "Actual Data Rate Downstream", "pppoed.tags.act_data_rate_down", FT_UINT32, BASE_DEC,
 817                                  NULL, 0x0, NULL, HFILL
 818                         }
 819                 },
 820                 { &hf_pppoed_tag_vspec_min_data_rate_up,
 821                         { "Minimum Data Rate Upstream", "pppoed.tags.min_data_rate_up", FT_UINT32, BASE_DEC,
 822                                  NULL, 0x0, NULL, HFILL
 823                         }
 824                 },
 825                 { &hf_pppoed_tag_vspec_min_data_rate_down,
 826                         { "Minimum Data Rate Downstream", "pppoed.tags.min_data_rate_down", FT_UINT32, BASE_DEC,
 827                                  NULL, 0x0, NULL, HFILL
 828                         }
 829                 },
 830                 { &hf_pppoed_tag_vspec_attainable_data_rate_up,
 831                         { "Attainable DataRate Upstream", "pppoed.tags.attainable_data_rate_up", FT_UINT32, BASE_DEC,
 832                                  NULL, 0x0, NULL, HFILL
 833                         }
 834                 },
 835                 { &hf_pppoed_tag_vspec_attainable_data_rate_down,
 836                         { "Attainable DataRate Downstream", "pppoed.tags.attainable_data_rate_down", FT_UINT32, BASE_DEC,
 837                                  NULL, 0x0, NULL, HFILL
 838                         }
 839                 },
 840                 { &hf_pppoed_tag_vspec_max_data_rate_up,
 841                         { "Maximum Data Rate Upstream", "pppoed.tags.max_data_rate_up", FT_UINT32, BASE_DEC,
 842                                  NULL, 0x0, NULL, HFILL
 843                         }
 844                 },
 845                 { &hf_pppoed_tag_vspec_max_data_rate_down,
 846                         { "Maximum Data Rate Downstream", "pppoed.tags.max_data_rate_down", FT_UINT32, BASE_DEC,
 847                                  NULL, 0x0, NULL, HFILL
 848                         }
 849                 },
 850                 { &hf_pppoed_tag_vspec_min_data_rate_up_lp,
 851                         { "Min DataRate Upstream in low power state", "pppoed.tags.min_data_rate_up_lp", FT_UINT32, BASE_DEC,
 852                                  NULL, 0x0, NULL, HFILL
 853                         }
 854                 },
 855                 { &hf_pppoed_tag_vspec_min_data_rate_down_lp,
 856                         { "Minimum Data Rate Downstream in low power state", "pppoed.tags.min_data_rate_down_lp", FT_UINT32, BASE_DEC,
 857                                  NULL, 0x0, NULL, HFILL
 858                         }
 859                 },
 860                 { &hf_pppoed_tag_vspec_max_int_delay_up,
 861                         { "Max Interleaving Delay Upstream", "pppoed.tags.max_int_delay_up", FT_UINT32, BASE_DEC,
 862                                  NULL, 0x0, NULL, HFILL
 863                         }
 864                 },
 865                 { &hf_pppoed_tag_vspec_act_int_delay_up,
 866                         { "Actual Interleaving Delay Upstream", "pppoed.tags.act_int_delay_up", FT_UINT32, BASE_DEC,
 867                                  NULL, 0x0, NULL, HFILL
 868                         }
 869                 },
 870                 { &hf_pppoed_tag_vspec_max_int_delay_down,
 871                         { "Maximum Interleaving Delay Downstream", "pppoed.tags.max_int_delay_down", FT_UINT32, BASE_DEC,
 872                                  NULL, 0x0, NULL, HFILL
 873                         }
 874                 },
 875                 { &hf_pppoed_tag_vspec_act_int_delay_down,
 876                         { "Actual Interleaving Delay Downstream", "pppoed.tags.act_int_delay_down", FT_UINT32, BASE_DEC,
 877                                  NULL, 0x0, NULL, HFILL
 878                         }
 879                 },
 880                 { &hf_pppoed_tag_vspec_access_loop_encapsulation,
 881                         { "Access-Loop-Encapsulation", "pppoed.tags.access_loop_encap", FT_NONE, BASE_NONE,
 882                                  NULL, 0x0, NULL, HFILL
 883                         }
 884                 },
 885                 { &hf_pppoed_tag_vspec_access_loop_encap_data_link,
 886                         { "Data link", "pppoed.tags.access_loop_encap.data_link", FT_UINT8, BASE_HEX,
 887                                  VALS(vspec_tag_dslf_access_loop_encap_data_link_vals), 0x0, NULL, HFILL
 888                         }
 889                 },
 890                 { &hf_pppoed_tag_vspec_access_loop_encap_encap_1,
 891                         { "Encaps 1", "pppoed.tags.access_loop_encap.encap_1", FT_UINT8, BASE_HEX,
 892                                  VALS(vspec_tag_dslf_access_loop_encap_encap_1_vals), 0x0, NULL, HFILL
 893                         }
 894                 },
 895                 { &hf_pppoed_tag_vspec_access_loop_encap_encap_2,
 896                         { "Encaps 1", "pppoed.tags.access_loop_encap.encap_2", FT_UINT8, BASE_HEX,
 897                                  VALS(vspec_tag_dslf_access_loop_encap_encap_2_vals), 0x0, NULL, HFILL
 898                         }
 899                 },
 900                 { &hf_pppoed_tag_credits,
 901                         { "Credits", "pppoed.tags.credits", FT_BYTES, BASE_NONE,
 902                                  NULL, 0x0, NULL, HFILL
 903                         }
 904                 },
 905                 { &hf_pppoed_tag_credits_fcn,
 906                         { "FCN", "pppoed.tags.credits.fcn", FT_UINT16, BASE_DEC,
 907                                  NULL, 0x0, NULL, HFILL
 908                         }
 909                 },
 910                 { &hf_pppoed_tag_credits_bcn,
 911                         { "BCN", "pppoed.tags.credits.bcn", FT_UINT16, BASE_DEC,
 912                                  NULL, 0x0, NULL, HFILL
 913                         }
 914                 },
 915                 { &hf_pppoed_tag_metrics,
 916                         { "Metrics", "pppoed.tags.metrics", FT_BYTES, BASE_NONE,
 917                                  NULL, 0x0, NULL, HFILL
 918                         }
 919                 },
 920                 { &hf_pppoed_tag_metrics_r,
 921                         { "Receive Only", "pppoed.tags.metrics.r", FT_BOOLEAN, 16,
 922                                  NULL, PPPOE_RCV_ONLY_MASK, NULL, HFILL
 923                         }
 924                 },
 925                 { &hf_pppoed_tag_mdr_units,
 926                         { "MDR Units", "pppoed.tags.metrics.mdr_units", FT_UINT16, BASE_HEX,
 927                                  VALS(datarate_scale_vals), PPPOE_MDR_MASK, NULL, HFILL
 928                         }
 929                 },
 930                 { &hf_pppoed_tag_cdr_units,
 931                         { "CDR Units", "pppoed.tags.metrics.cdr_units", FT_UINT16, BASE_HEX,
 932                                  VALS(datarate_scale_vals), PPPOE_CDR_MASK, NULL, HFILL
 933                         }
 934                 },
 935                 { &hf_pppoed_tag_metrics_rlq,
 936                         { "Relative Link Quality", "pppoed.tags.metrics.rlq", FT_UINT8, BASE_DEC,
 937                                  NULL, 0x0, NULL, HFILL
 938                         }
 939                 },
 940                 { &hf_pppoed_tag_metrics_resource,
 941                         { "Resource", "pppoed.tags.metrics.resource", FT_UINT8, BASE_DEC,
 942                                  NULL, 0x0, NULL, HFILL
 943                         }
 944                 },
 945                 { &hf_pppoed_tag_metrics_latency,
 946                         { "Latency", "pppoed.tags.metrics.latency", FT_UINT16, BASE_DEC,
 947                                  NULL, 0x0, NULL, HFILL
 948                         }
 949                 },
 950                 { &hf_pppoed_tag_metrics_curr_drate,
 951                         { "Curr. datarate", "pppoed.tags.metrics.curr_drate", FT_UINT16, BASE_DEC,
 952                                  NULL, 0x0, NULL, HFILL
 953                         }
 954                 },
 955                 { &hf_pppoed_tag_metrics_max_drate,
 956                         { "Max. datarate", "pppoed.tags.metrics.max_drate", FT_UINT16, BASE_DEC,
 957                                  NULL, 0x0, NULL, HFILL
 958                         }
 959                 },
 960                 { &hf_pppoed_tag_seq_num,
 961                         { "Sequence Number", "pppoed.tags.seq_num", FT_UINT16, BASE_HEX,
 962                                  NULL, 0x0, NULL, HFILL
 963                         }
 964                 },
 965                 { &hf_pppoed_tag_cred_scale,
 966                         { "Credit Scale Factor", "pppoed.tags.credit_scale", FT_UINT16, BASE_DEC,
 967                                  NULL, 0x0, NULL, HFILL
 968                         }
 969                 },
 970                 { &hf_pppoed_tag_relay_session_id,
 971                         { "Relay-Session-Id", "pppoed.tags.relay_session_id", FT_BYTES, BASE_NONE,
 972                                  NULL, 0x0, NULL, HFILL
 973                         }
 974                 },
 975                 { &hf_pppoed_tag_hurl,
 976                         { "HURL", "pppoed.tags.hurl", FT_BYTES, BASE_NONE,
 977                                  NULL, 0x0, NULL, HFILL
 978                         }
 979                 },
 980                 { &hf_pppoed_tag_motm,
 981                         { "MOTM", "pppoed.tags.motm", FT_BYTES, BASE_NONE,
 982                                  NULL, 0x0, NULL, HFILL
 983                         }
 984                 },
 985                 { &hf_pppoed_tag_max_payload,
 986                         { "PPP Max Palyload", "pppoed.tags.max_payload", FT_BYTES, BASE_NONE,
 987                                  NULL, 0x0, NULL, HFILL
 988                         }
 989                 },
 990                 { &hf_pppoed_tag_ip_route_add,
 991                         { "IP Route Add", "pppoed.tags.ip_route_add", FT_BYTES, BASE_NONE,
 992                                  NULL, 0x0, NULL, HFILL
 993                         }
 994                 },
 995                 { &hf_pppoed_tag_service_name_error,
 996                         { "Service-Name-Error", "pppoed.tags.service_name_error", FT_STRING, BASE_NONE,
 997                                  NULL, 0x0, NULL, HFILL
 998                         }
 999                 },
1000                 { &hf_pppoed_tag_ac_system_error,
1001                         { "AC-System-Error", "pppoed.tags.ac_system_error", FT_STRING, BASE_NONE,
1002                                  NULL, 0x0, NULL, HFILL
1003                         }
1004                 },
1005                 { &hf_pppoed_tag_generic_error,
1006                         { "Generic-Error", "pppoed.tags.generic_error", FT_STRING, BASE_NONE,
1007                                  NULL, 0x0, NULL, HFILL
1008                         }
1009                 }
1010         };
1011
1012         static gint *ett[] = {
1013                 &ett_pppoed,
1014                 &ett_pppoed_tags,
1015                 &ett_pppoed_tag_vspec_dslf_access_loop_encaps
1016         };
1017
1018         module_t *pppoed_module;
1019
1020         /* Register protocol and fields */
1021         proto_pppoed = proto_register_protocol("PPP-over-Ethernet Discovery",
1022                                                "PPPoED", "pppoed");
1023         proto_register_subtree_array(ett, array_length(ett));
1024         proto_register_field_array(proto_pppoed, hf, array_length(hf));
1025
1026         /* Preference setting */
1027         pppoed_module = prefs_register_protocol(proto_pppoed, NULL);
1028         prefs_register_bool_preference(pppoed_module, "show_tags_and_lengths",
1029                                        "Show tag values and lengths",
1030                                        "Show values of tags and lengths of data fields",
1031                                        &global_pppoe_show_tags_and_lengths);
1032 }
1033
1034 void proto_reg_handoff_pppoed(void)
1035 {
1036         dissector_handle_t pppoed_handle;
1037
1038         pppoed_handle = create_dissector_handle(dissect_pppoed, proto_pppoed);
1039         dissector_add_uint("ethertype", ETHERTYPE_PPPOED, pppoed_handle);
1040 }
1041
1042
1043 /* Session protocol, i.e. PPP session established */
1044 static void dissect_pppoes(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
1045 {
1046         guint8  pppoe_code;
1047         guint16 pppoe_session_id;
1048         guint16 reported_payload_length;
1049         guint16 poe_tag;
1050         guint16 poe_tag_length;
1051         gint    actual_payload_length;
1052         gint    length, reported_length;
1053         gint    credit_offset = 0, tagstart = 0;
1054         guint16 cp_code;
1055
1056         proto_tree  *pppoe_tree;
1057         proto_item  *ti = NULL;
1058         tvbuff_t    *next_tvb;
1059
1060         col_set_str(pinfo->cinfo, COL_PROTOCOL, "PPPoES");
1061         col_clear(pinfo->cinfo, COL_INFO);
1062
1063         /* Start Decoding Here. */
1064         pppoe_code = tvb_get_guint8(tvb, 1);
1065
1066         if (check_col(pinfo->cinfo,COL_INFO))
1067         {
1068                 col_add_str(pinfo->cinfo, COL_INFO,
1069                              val_to_str(pppoe_code, code_vals, "Unknown"));
1070         }
1071
1072         pppoe_session_id = tvb_get_ntohs(tvb, 2);
1073         reported_payload_length = tvb_get_ntohs(tvb, 4);
1074         actual_payload_length = tvb_reported_length_remaining(tvb, 6);
1075
1076         if (tree)
1077         {
1078                 ti = proto_tree_add_item(tree, proto_pppoes, tvb, 0, 6, FALSE);
1079                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoe);
1080
1081                 proto_tree_add_item(pppoe_tree, hf_pppoe_version, tvb, 0, 1, FALSE);
1082                 proto_tree_add_item(pppoe_tree, hf_pppoe_type, tvb, 0, 1, FALSE);
1083                 proto_tree_add_item(pppoe_tree, hf_pppoe_code, tvb, 1, 1, FALSE);
1084                 proto_tree_add_item(pppoe_tree, hf_pppoe_session_id, tvb, 2, 2, FALSE);
1085                 ti = proto_tree_add_item(pppoe_tree, hf_pppoe_payload_length, tvb, 4, 2, FALSE);
1086
1087
1088                 if (PPPOE_TAG_CREDITS == tvb_get_ntohs(tvb, 6))
1089                 {
1090                         tagstart = 6;
1091                         poe_tag = tvb_get_ntohs(tvb, tagstart);
1092                         poe_tag_length = tvb_get_ntohs(tvb, tagstart + 2);
1093
1094                         /* Create tags subtree */
1095                         ti = proto_tree_add_item(pppoe_tree, hf_pppoes_tags, tvb, tagstart, 8, FALSE);
1096                         pppoe_tree = proto_item_add_subtree(ti, ett_pppoes_tags);
1097
1098                         /* Show tag data */
1099                         if (poe_tag_length == 4)
1100                         {
1101                                 proto_tree_add_item(pppoe_tree, hf_pppoes_tag_credits_fcn, tvb,
1102                                         tagstart+4, 2, FALSE);
1103                                 proto_tree_add_item(pppoe_tree, hf_pppoes_tag_credits_bcn, tvb,
1104                                         tagstart+6, 2, FALSE);
1105                         } else {
1106                                 proto_tree_add_item(pppoe_tree, hf_pppoed_tag_credits, tvb,
1107                                         tagstart+4, poe_tag_length, FALSE);
1108                         }
1109
1110                         credit_offset = 8;
1111                 }
1112         }
1113
1114         /*
1115          * The only reason why the payload length from the header
1116          * should differ from the remaining data in the packet
1117          * would be if the total packet length, including Ethernet
1118          * CRC, were < 64 bytes, so that padding was required.
1119          *
1120          * That means that you have 14 bytes of Ethernet header,
1121          * 4 bytes of FCS, and fewer than 46 bytes of PPPoE packet.
1122          *
1123          * If that's not the case, we report a difference between
1124          * the payload length in the packet, and the amount of
1125          * data following the PPPoE header, as an error.
1126          */
1127         if (tvb_reported_length(tvb) > 46) {
1128                 /*
1129                  * Be forgiving about a possible trailing FCS.
1130                  *
1131                  * XXX - this dissector currently doesn't know
1132                  * whether any extra data past the end of the PPP
1133                  * payload is an FCS or not.
1134                  *
1135                  * If we know that we have an FCS, or that we don't
1136                  * have an FCS, we should have been handed a tvbuff
1137                  * without the FCS, and we should just do the strict
1138                  * length check.
1139                  *
1140                  * If we don't know whether we have an FCS, then:
1141                  *
1142                  *   if this isn't over Ethernet - the "E" in "PPPoE"
1143                  *   nonwithstanding, it can also run on top of 802.11,
1144                  *   for example - there's no trailer, so any data
1145                  *   past the payload length is either an FCS or
1146                  *   bogus;
1147                  *
1148                  *   if this is over Ethernet, there shouldn't be
1149                  *   a trailer, as the packet is long enough not to
1150                  *   require a trailer, as per the above;
1151                  *
1152                  * so perhaps we should assume that if we have exactly
1153                  * 4 bytes of extra information, it's an FCS, otherwise
1154                  * it's not.
1155                  *
1156                  * Perhaps we need to have a routine to call to
1157                  * do all the length checking, etc., and call it
1158                  * from here and from other dissectors where the
1159                  * protocol has a length field, or have a way to
1160                  * tell the dissector that called us which field
1161                  * has the length field and have *that* dissector
1162                  * do the length checking and add the expert info
1163                  * to the length field, *after* it does all the
1164                  * FCS heuristics.
1165                  */
1166
1167                 /* retrieve the control protocol code if it's there */
1168                 cp_code = tvb_get_ntohs(tvb, 6);
1169                 /*
1170                  * The session payload length expressly does not include pad bytes
1171                  *  when LCP or IPCP are present, so avoid the spurious error message
1172                  */
1173                 if ((cp_code != PPP_LCP) && (cp_code != PPP_IPCP) &&
1174                         (reported_payload_length != actual_payload_length) &&
1175                         ((reported_payload_length + 4) != actual_payload_length)) {
1176                         proto_item_append_text(ti, " [incorrect, should be %u]",
1177                                 actual_payload_length);
1178                         expert_add_info_format(pinfo, ti, PI_MALFORMED,
1179                                 PI_WARN, "Possible bad payload length %u != %u",
1180                                 reported_payload_length, actual_payload_length);
1181                 }
1182         }
1183
1184         /*
1185          * Construct a tvbuff containing the PPP packet.
1186          */
1187         length = tvb_length_remaining(tvb, 6);
1188         reported_length = tvb_reported_length_remaining(tvb, 6);
1189         DISSECTOR_ASSERT(length >= 0);
1190         DISSECTOR_ASSERT(reported_length >= 0);
1191         if (length > reported_length)
1192                 length = reported_length;
1193         if ((guint)length > reported_payload_length)
1194                 length = reported_payload_length;
1195         if ((guint)reported_length > reported_payload_length)
1196                 reported_length = reported_payload_length;
1197         next_tvb = tvb_new_subset(tvb,(6 + credit_offset),
1198                                 (length - credit_offset),
1199                                 (reported_length - credit_offset));
1200         call_dissector(ppp_handle,next_tvb,pinfo,tree);
1201 }
1202
1203 void proto_register_pppoes(void)
1204 {
1205
1206         static hf_register_info hf[] =
1207         {
1208                 { &hf_pppoes_tags,
1209                         { "PPPoE Tags", "pppoes.tags", FT_NONE, BASE_NONE,
1210                                  NULL, 0x0, NULL, HFILL
1211                         }
1212                 },
1213                 { &hf_pppoes_tag,
1214                         { "Tag", "pppoes.tag", FT_UINT16, BASE_HEX,
1215                                  VALS(tag_vals), 0x0, NULL, HFILL
1216                         }
1217                 },
1218                 { &hf_pppoes_tag_credits,
1219                         { "Credits", "pppoes.tags.credits", FT_BYTES, BASE_NONE,
1220                                  NULL, 0x0, NULL, HFILL
1221                         }
1222                 },
1223                 { &hf_pppoes_tag_credits_fcn,
1224                         { "FCN", "pppoes.tags.credits.fcn", FT_UINT16, BASE_DEC,
1225                                  NULL, 0x0, NULL, HFILL
1226                         }
1227                 },
1228                 { &hf_pppoes_tag_credits_bcn,
1229                         { "BCN", "pppoes.tags.credits.bcn", FT_UINT16, BASE_DEC,
1230                                  NULL, 0x0, NULL, HFILL
1231                         }
1232                 }
1233         };
1234
1235         static gint *ett[] = {
1236                 &ett_pppoes,
1237                 &ett_pppoes_tags
1238         };
1239
1240         /* Register protocol */
1241         proto_pppoes = proto_register_protocol("PPP-over-Ethernet Session", "PPPoES", "pppoes");
1242
1243         proto_register_subtree_array(ett, array_length(ett));
1244         proto_register_field_array(proto_pppoes, hf, array_length(hf));
1245 }
1246
1247 void proto_register_pppoe(void)
1248 {
1249         static hf_register_info hf[] =
1250         {
1251                 /* These fields common to discovery and session protocols */
1252                 { &hf_pppoe_version,
1253                         { "Version", "pppoe.version", FT_UINT8, BASE_DEC,
1254                                  NULL, 0xf0, NULL, HFILL
1255                         }
1256                 },
1257                 { &hf_pppoe_type,
1258                         { "Type", "pppoe.type", FT_UINT8, BASE_DEC,
1259                                  NULL, 0x0f, NULL, HFILL
1260                         }
1261                 },
1262                 { &hf_pppoe_code,
1263                         { "Code", "pppoe.code", FT_UINT8, BASE_HEX,
1264                                  VALS(code_vals), 0x0, NULL, HFILL
1265                         }
1266                 },
1267                 { &hf_pppoe_session_id,
1268                         { "Session ID", "pppoe.session_id", FT_UINT16, BASE_HEX,
1269                                  NULL, 0x0, NULL, HFILL
1270                         }
1271                 },
1272                 { &hf_pppoe_payload_length,
1273                         { "Payload Length", "pppoe.payload_length", FT_UINT16, BASE_DEC,
1274                                  NULL, 0x0, NULL, HFILL
1275                         }
1276                 }
1277         };
1278
1279         static gint *ett[] = {
1280                 &ett_pppoe
1281         };
1282
1283         /* Register protocol */
1284         proto_pppoe = proto_register_protocol("PPP-over-Ethernet", "PPPoE", "pppoe");
1285
1286         proto_register_subtree_array(ett, array_length(ett));
1287         proto_register_field_array(proto_pppoe, hf, array_length(hf));
1288
1289 }
1290
1291 void proto_reg_handoff_pppoes(void)
1292 {
1293         dissector_handle_t pppoes_handle  =
1294             create_dissector_handle(dissect_pppoes, proto_pppoes);
1295         dissector_add_uint("ethertype", ETHERTYPE_PPPOES, pppoes_handle);
1296
1297         /* Get a handle for the PPP dissector */
1298         ppp_handle = find_dissector("ppp");
1299 }