packet-pppoe.c

   1 /* packet-arp.c
   2  * Routines for ARP packet disassembly
   3  *
   4  * $Id: packet-pppoe.c,v 1.4 1999/11/16 11:42:48 guy 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
  37 static gint ett_pppoed = -1;
  38 static gint ett_pppoed_tags = -1;
  39
  40 /* For lack of a better source, I made up the following defines. -jsj */
  41
  42 #define PPPOE_CODE_SESSION 0x00
  43 #define PPPOE_CODE_PADO 0x7
  44 #define PPPOE_CODE_PADI 0x9
  45 #define PPPOE_CODE_PADR 0x19
  46 #define PPPOE_CODE_PADS 0x65
  47 #define PPPOE_CODE_PADT 0xa7
  48
  49 #define PPPOE_TAG_EOL 0x0000
  50 #define PPPOE_TAG_SVC_NAME 0x0101
  51 #define PPPOE_TAG_AC_NAME 0x0102
  52 #define PPPOE_TAG_HOST_UNIQ 0x0103
  53 #define PPPOE_TAG_AC_COOKIE 0x0104
  54 #define PPPOE_TAG_VENDOR 0x0105
  55 #define PPPOE_TAG_RELAY_ID 0x0110
  56 #define PPPOE_TAG_SVC_ERR 0x0201
  57 #define PPPOE_TAG_AC_ERR 0x0202
  58 #define PPPOE_TAG_GENERIC_ERR 0x0203
  59
  60 gchar *
  61 pppoecode_to_str(guint8 codetype, const char *fmt) {
  62         static const value_string code_vals[] = {
  63                 {PPPOE_CODE_SESSION, "Session Data"                             },
  64                 {PPPOE_CODE_PADO, "Active Discovery Offer (PADO)"               },
  65                 {PPPOE_CODE_PADI, "Active Discovery Initiation (PADI)"          },
  66                 {PPPOE_CODE_PADR, "Active Discovery Request (PADR)"             },
  67                 {PPPOE_CODE_PADS, "Active Discovery Session-confirmation (PADS)"},
  68                 {PPPOE_CODE_PADT, "Active Discovery Terminate (PADT)"           },
  69                 {0,     NULL                                                        } };
  70
  71                 return val_to_str(codetype, code_vals, fmt);
  72 }
  73
  74 gchar *
  75 pppoetag_to_str(guint16 tag_type, const char *fmt) {
  76         static const value_string code_vals[] = {
  77                 {PPPOE_TAG_EOL,        "End-Of-List"       },
  78                 {PPPOE_TAG_SVC_NAME,   "Service-Name"      },
  79                 {PPPOE_TAG_AC_NAME,    "AC-Name"           },
  80                 {PPPOE_TAG_HOST_UNIQ,  "Host-Uniq"         },
  81                 {PPPOE_TAG_AC_COOKIE,  "AC-Cookie"         },
  82                 {PPPOE_TAG_VENDOR,     "Vendor-Specific"   },
  83                 {PPPOE_TAG_RELAY_ID,   "Relay-Session-Id"  },
  84                 {PPPOE_TAG_SVC_ERR,    "Service-Name-Error"},
  85                 {PPPOE_TAG_AC_ERR,     "AC-System-Error"   },
  86                 {PPPOE_TAG_GENERIC_ERR,"Generic-Error"     },
  87                 {0,                    NULL                } };
  88
  89                 return val_to_str(tag_type, code_vals, fmt);
  90 }
  91
  92
  93 void
  94 dissect_pppoe_tags(const u_char *pd, int offset, frame_data *fd, proto_tree *tree, int payload_length) {
  95
  96         guint16 poe_tag;
  97         guint16 poe_tag_length;
  98         int tagstart;
  99
 100         proto_tree  *pppoe_tree;
 101         proto_item  *ti;
 102
 103         /* Start Decoding Here. */
 104
 105         if (tree) {
 106                 ti = proto_tree_add_text(tree,offset,payload_length,"PPPoE Tags");
 107                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed_tags);
 108
 109                 tagstart = offset;
 110                 while(tagstart <= payload_length-2 ) {
 111
 112                         poe_tag = pntohs(&pd[tagstart]);
 113                         poe_tag_length = pntohs(&pd[tagstart + 2]);
 114
 115                         proto_tree_add_text(pppoe_tree,tagstart,4,
 116                                 "Tag: %s", pppoetag_to_str(poe_tag,"Unknown (0x%02x)"));
 117
 118                         switch(poe_tag) {
 119                         case PPPOE_TAG_SVC_NAME:
 120                         case PPPOE_TAG_AC_NAME:
 121                         case PPPOE_TAG_SVC_ERR:
 122                         case PPPOE_TAG_AC_ERR:
 123                         case PPPOE_TAG_GENERIC_ERR:
 124                                 /* tag value should be interpreted as a utf-8 unterminated string.*/
 125                                 if(poe_tag_length > 0 ) {
 126                                         /* really should do some limit checking here.  :( */
 127                                         proto_tree_add_text(pppoe_tree,tagstart+4,poe_tag_length,
 128                                                 "  String Data: %s", format_text(&pd[tagstart+4],poe_tag_length ));
 129                                 }
 130                                 break;
 131                         default:
 132                                 if(poe_tag_length > 0 ) {
 133                                  proto_tree_add_text(pppoe_tree,tagstart+4,poe_tag_length,
 134                                                 "  Binary Data: (%d bytes)", poe_tag_length );
 135                                 }
 136                         }
 137
 138                         if (poe_tag == PPPOE_TAG_EOL) break;
 139
 140                         tagstart += 4 + poe_tag_length;
 141                 }
 142         }
 143 }
 144
 145 void
 146 dissect_pppoed(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 147         guint8 pppoe_ver;
 148         guint8 pppoe_type;
 149         guint8  pppoe_code;
 150         guint16 pppoe_session_id;
 151         guint16 pppoe_length;
 152
 153         proto_tree  *pppoe_tree;
 154         proto_item  *ti;
 155
 156         /* Start Decoding Here. */
 157         pppoe_ver = (guint8) ((pd[offset] >> 4) & 0x0f);
 158         pppoe_type = (guint8) (pd[offset] & 0x0f);
 159         pppoe_code = (guint8) pd[offset + 1];
 160         pppoe_session_id = pntohs(&pd[offset + 2]);
 161         pppoe_length = pntohs(&pd[offset + 4]);
 162
 163         if (check_col(fd, COL_PROTOCOL)) {
 164                 col_add_str(fd,COL_PROTOCOL, "PPPoED");
 165         }
 166
 167         if (check_col(fd,COL_INFO)) {
 168                 col_add_fstr(fd,COL_INFO,pppoecode_to_str(pppoe_code,"Unknown code (0x%02x)"));
 169         }
 170
 171         if (tree) {
 172                 ti = proto_tree_add_text(tree,offset,pppoe_length+6,"PPPoE Discovery");
 173                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
 174                 proto_tree_add_text(pppoe_tree,offset,1,
 175                         "Version: %d", pppoe_ver);
 176                 proto_tree_add_text(pppoe_tree,offset,1,
 177                         "Type: %d", pppoe_type);
 178                 proto_tree_add_text(pppoe_tree,offset+1,1,
 179                         "Code: %s", pppoecode_to_str(pppoe_code,"Unknown (0x%02x)"));
 180                 proto_tree_add_text(pppoe_tree,offset+2,2,
 181                         "Session ID: %04x", pppoe_session_id);
 182                 proto_tree_add_text(pppoe_tree,offset+4,2,
 183                         "Payload Length: %d", pppoe_length);
 184         }
 185         dissect_pppoe_tags(pd,offset+6,fd,tree,offset+6+pppoe_length);
 186
 187 }
 188
 189 void
 190 dissect_pppoes(const u_char *pd, int offset, frame_data *fd, proto_tree *tree) {
 191         guint8 pppoe_ver;
 192         guint8 pppoe_type;
 193         guint8  pppoe_code;
 194         guint16 pppoe_session_id;
 195         guint16 pppoe_length;
 196
 197         proto_tree  *pppoe_tree;
 198         proto_item  *ti;
 199
 200         /* Start Decoding Here. */
 201         pppoe_ver = (guint8) ((pd[offset] >> 4) & 0x0f);
 202         pppoe_type = (guint8) (pd[offset] & 0x0f);
 203         pppoe_code = (guint8) pd[offset + 1];
 204         pppoe_session_id = pntohs(&pd[offset + 2]);
 205         pppoe_length = pntohs(&pd[offset + 4]);
 206
 207         if (check_col(fd, COL_PROTOCOL)) {
 208                 col_add_str(fd,COL_PROTOCOL, "PPPoES");
 209         }
 210
 211         if (check_col(fd,COL_INFO)) {
 212                 col_add_fstr(fd,COL_INFO,pppoecode_to_str(pppoe_code,"Unknown code (0x%02x)"));
 213         }
 214
 215         if (tree) {
 216                 ti = proto_tree_add_text(tree,offset,pppoe_length+6,"PPPoE Session");
 217                 pppoe_tree = proto_item_add_subtree(ti, ett_pppoed);
 218                 proto_tree_add_text(pppoe_tree,offset,1,
 219                         "Version: %d", pppoe_ver);
 220                 proto_tree_add_text(pppoe_tree,offset,1,
 221                         "Type: %d", pppoe_type);
 222                 proto_tree_add_text(pppoe_tree,offset+1,1,
 223                         "Code: %s", pppoecode_to_str(pppoe_code,"Unknown (0x%02x)"));
 224                 proto_tree_add_text(pppoe_tree,offset+2,2,
 225                         "Session ID: %04x", pppoe_session_id);
 226                 proto_tree_add_text(pppoe_tree,offset+4,2,
 227                         "Payload Length: %d", pppoe_length);
 228         }
 229         /* dissect_ppp is apparently done as a 'top level' dissector,
 230                 * so this doesn't work:
 231                 * dissect_ppp(pd,offset+6,fd,tree);
 232                 * Im gonna try fudging it.
 233                 */
 234
 235         dissect_payload_ppp(pd,offset+6,fd,tree);
 236 }
 237
 238 void
 239 proto_register_pppoed(void)
 240 {
 241         static gint *ett[] = {
 242                 &ett_pppoed,
 243                 &ett_pppoed_tags,
 244         };
 245
 246         proto_register_subtree_array(ett, array_length(ett));
 247 }
 248