packet-pppoe.c

   1 /* packet-arp.c
   2  * Routines for ARP packet disassembly
   3  *
   4  * $Id: packet-pppoe.c,v 1.5 2000/02/15 21:02:54 gram Exp $
   5  *
   6  * Ethereal - Network traffic analyzer
   7  * By Gerald Combs <gerald@zing.org>
   8  * Copyright 1998 Gerald Combs
   9  *
  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 #ifdef HAVE_SYS_TYPES_H
  31 # include <sys/types.h>
  32 #endif
  33
  34 #include <glib.h>
  35 #include "packet.h"
  36 #include "packet-ppp.h"
  37
  38 static gint ett_pppoed = -1;
  39 static gint ett_pppoed_tags = -1;
  40
  41 /* For lack of a better source, I made up the following defines. -jsj */
  42
  43 #define PPPOE_CODE_SESSION 0x00
  44 #define PPPOE_CODE_PADO 0x7
  45 #define PPPOE_CODE_PADI 0x9
  46 #define PPPOE_CODE_PADR 0x19
  47 #define PPPOE_CODE_PADS 0x65
  48 #define PPPOE_CODE_PADT 0xa7
  49
  50 #define PPPOE_TAG_EOL 0x0000
  51 #define PPPOE_TAG_SVC_NAME 0x0101
  52 #define PPPOE_TAG_AC_NAME 0x0102
  53 #define PPPOE_TAG_HOST_UNIQ 0x0103
  54 #define PPPOE_TAG_AC_COOKIE 0x0104
  55 #define PPPOE_TAG_VENDOR 0x0105
  56 #define PPPOE_TAG_RELAY_ID 0x0110
  57 #define PPPOE_TAG_SVC_ERR 0x0201
  58 #define PPPOE_TAG_AC_ERR 0x0202
  59 #define PPPOE_TAG_GENERIC_ERR 0x0203
  60
  61 gchar *
  62 pppoecode_to_str(guint8 codetype, const char *fmt) {
  63         static const value_string code_vals[] = {
  64                 {PPPOE_CODE_SESSION, "Session Data"                             },
  65                 {PPPOE_CODE_PADO, "Active Discovery Offer (PADO)"               },
  66                 {PPPOE_CODE_PADI, "Active Discovery Initiation (PADI)"          },
  67                 {PPPOE_CODE_PADR, "Active Discovery Request (PADR)"             },
  68                 {PPPOE_CODE_PADS, "Active Discovery Session-confirmation (PADS)"},
  69                 {PPPOE_CODE_PADT, "Active Discovery Terminate (PADT)"           },
  70                 {0,     NULL                                                        } };
  71
  72                 return val_to_str(codetype, code_vals, fmt);
  73 }
  74
  75 gchar *
  76 pppoetag_to_str(guint16 tag_type, const char *fmt) {
  77         static const value_string code_vals[] = {
  78                 {PPPOE_TAG_EOL,        "End-Of-List"       },
  79                 {PPPOE_TAG_SVC_NAME,   "Service-Name"      },
  80                 {PPPOE_TAG_AC_NAME,    "AC-Name"           },
  81                 {PPPOE_TAG_HOST_UNIQ,  "Host-Uniq"         },
  82                 {PPPOE_TAG_AC_COOKIE,  "AC-Cookie"         },
  83                 {PPPOE_TAG_VENDOR,     "Vendor-Specific"   },
  84                 {PPPOE_TAG_RELAY_ID,   "Relay-Session-Id"  },
  85                 {PPPOE_TAG_SVC_ERR,    "Service-Name-Error"},
  86                 {PPPOE_TAG_AC_ERR,     "AC-System-Error"   },
  87                 {PPPOE_TAG_GENERIC_ERR,"Generic-Error"     },
  88                 {0,                    NULL                } };
  89
  90                 return val_to_str(tag_type, code_vals, fmt);
  91 }
  92
  93
  94 void
  95 dissect_pppoe_tags(const u_char *pd, int offset, frame_data *fd, proto_tree *tree, int payload_length) {
  96
  97         guint16 poe_tag;
  98         guint16 poe_tag_length;
  99         int tagstart;
 100
 101         proto_tree  *pppoe_tree;
 102         proto_item  *ti;
 103
 104         /* Start Decoding Here. */
 105
 106         if (tree) {
 107                 ti = proto_tree_add_text(tree,offset,payload_length,"PPPoE Tags");
 108                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed_tags);
 109
 110                 tagstart = offset;
 111                 while(tagstart <= payload_length-2 ) {
 112
 113                         poe_tag = pntohs(&pd[tagstart]);
 114                         poe_tag_length = pntohs(&pd[tagstart + 2]);
 115
 116                         proto_tree_add_text(pppoe_tree,tagstart,4,
 117                                 "Tag: %s", pppoetag_to_str(poe_tag,"Unknown (0x%02x)"));
 118
 119                         switch(poe_tag) {
 120                         case PPPOE_TAG_SVC_NAME:
 121                         case PPPOE_TAG_AC_NAME:
 122                         case PPPOE_TAG_SVC_ERR:
 123                         case PPPOE_TAG_AC_ERR:
 124                         case PPPOE_TAG_GENERIC_ERR:
 125                                 /* tag value should be interpreted as a utf-8 unterminated string.*/
 126                                 if(poe_tag_length > 0 ) {
 127                                         /* really should do some limit checking here.  :( */
 128                                         proto_tree_add_text(pppoe_tree,tagstart+4,poe_tag_length,
 129                                                 "  String Data: %s", format_text(&pd[tagstart+4],poe_tag_length ));
 130                                 }
 131                                 break;
 132                         default:
 133                                 if(poe_tag_length > 0 ) {
 134                                  proto_tree_add_text(pppoe_tree,tagstart+4,poe_tag_length,
 135                                                 "  Binary Data: (%d bytes)", poe_tag_length );
 136                                 }
 137                         }
 138
 139                         if (poe_tag == PPPOE_TAG_EOL) break;
 140
 141                         tagstart += 4 + poe_tag_length;
 142                 }
 143         }
 144 }
 145
 146 void
 147 dissect_pppoed(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 148         guint8 pppoe_ver;
 149         guint8 pppoe_type;
 150         guint8  pppoe_code;
 151         guint16 pppoe_session_id;
 152         guint16 pppoe_length;
 153
 154         proto_tree  *pppoe_tree;
 155         proto_item  *ti;
 156
 157         /* Start Decoding Here. */
 158         pppoe_ver = (guint8) ((pd[offset] >> 4) & 0x0f);
 159         pppoe_type = (guint8) (pd[offset] & 0x0f);
 160         pppoe_code = (guint8) pd[offset + 1];
 161         pppoe_session_id = pntohs(&pd[offset + 2]);
 162         pppoe_length = pntohs(&pd[offset + 4]);
 163
 164         if (check_col(fd, COL_PROTOCOL)) {
 165                 col_add_str(fd,COL_PROTOCOL, "PPPoED");
 166         }
 167
 168         if (check_col(fd,COL_INFO)) {
 169                 col_add_fstr(fd,COL_INFO,pppoecode_to_str(pppoe_code,"Unknown code (0x%02x)"));
 170         }
 171
 172         if (tree) {
 173                 ti = proto_tree_add_text(tree,offset,pppoe_length+6,"PPPoE Discovery");
 174                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
 175                 proto_tree_add_text(pppoe_tree,offset,1,
 176                         "Version: %d", pppoe_ver);
 177                 proto_tree_add_text(pppoe_tree,offset,1,
 178                         "Type: %d", pppoe_type);
 179                 proto_tree_add_text(pppoe_tree,offset+1,1,
 180                         "Code: %s", pppoecode_to_str(pppoe_code,"Unknown (0x%02x)"));
 181                 proto_tree_add_text(pppoe_tree,offset+2,2,
 182                         "Session ID: %04x", pppoe_session_id);
 183                 proto_tree_add_text(pppoe_tree,offset+4,2,
 184                         "Payload Length: %d", pppoe_length);
 185         }
 186         dissect_pppoe_tags(pd,offset+6,fd,tree,offset+6+pppoe_length);
 187
 188 }
 189
 190 void
 191 dissect_pppoes(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 192         guint8 pppoe_ver;
 193         guint8 pppoe_type;
 194         guint8  pppoe_code;
 195         guint16 pppoe_session_id;
 196         guint16 pppoe_length;
 197
 198         proto_tree  *pppoe_tree;
 199         proto_item  *ti;
 200
 201         /* Start Decoding Here. */
 202         pppoe_ver = (guint8) ((pd[offset] >> 4) & 0x0f);
 203         pppoe_type = (guint8) (pd[offset] & 0x0f);
 204         pppoe_code = (guint8) pd[offset + 1];
 205         pppoe_session_id = pntohs(&pd[offset + 2]);
 206         pppoe_length = pntohs(&pd[offset + 4]);
 207
 208         if (check_col(fd, COL_PROTOCOL)) {
 209                 col_add_str(fd,COL_PROTOCOL, "PPPoES");
 210         }
 211
 212         if (check_col(fd,COL_INFO)) {
 213                 col_add_fstr(fd,COL_INFO,pppoecode_to_str(pppoe_code,"Unknown code (0x%02x)"));
 214         }
 215
 216         if (tree) {
 217                 ti = proto_tree_add_text(tree,offset,pppoe_length+6,"PPPoE Session");
 218                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
 219                 proto_tree_add_text(pppoe_tree,offset,1,
 220                         "Version: %d", pppoe_ver);
 221                 proto_tree_add_text(pppoe_tree,offset,1,
 222                         "Type: %d", pppoe_type);
 223                 proto_tree_add_text(pppoe_tree,offset+1,1,
 224                         "Code: %s", pppoecode_to_str(pppoe_code,"Unknown (0x%02x)"));
 225                 proto_tree_add_text(pppoe_tree,offset+2,2,
 226                         "Session ID: %04x", pppoe_session_id);
 227                 proto_tree_add_text(pppoe_tree,offset+4,2,
 228                         "Payload Length: %d", pppoe_length);
 229         }
 230         /* dissect_ppp is apparently done as a 'top level' dissector,
 231                 * so this doesn't work:
 232                 * dissect_ppp(pd,offset+6,fd,tree);
 233                 * Im gonna try fudging it.
 234                 */
 235
 236         dissect_payload_ppp(pd,offset+6,fd,tree);
 237 }
 238
 239 void
 240 proto_register_pppoed(void)
 241 {
 242         static gint *ett[] = {
 243                 &ett_pppoed,
 244                 &ett_pppoed_tags,
 245         };
 246
 247         proto_register_subtree_array(ett, array_length(ett));
 248 }
 249