The Tcpdump Group git mirrors - tcpdump/blob - print-pppoe.c

   1 /*
   2  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char rcsid[] =
  24 "@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.5 2000-07-10 04:36:19 assar Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <sys/param.h>
  32 #include <sys/time.h>
  33 #include <sys/socket.h>
  34
  35 struct mbuf;
  36 struct rtentry;
  37 #include <net/if.h>
  38
  39 #include <netinet/in.h>
  40 #include <netinet/if_ether.h>
  41
  42 #include <stdio.h>
  43 #include <string.h>
  44
  45 #include "interface.h"
  46 #include "addrtoname.h"
  47 #include "ppp.h"
  48 #include "ethertype.h"
  49 #include "extract.h"                    /* must come after interface.h */
  50
  51 /* Codes */
  52 enum {
  53   PPPOE_PADI = 0x09,
  54   PPPOE_PADO = 0x07,
  55   PPPOE_PADR = 0x19,
  56   PPPOE_PADS = 0x65,
  57   PPPOE_PADT = 0xa7
  58 };
  59
  60 static struct tok pppoecode2str[] = {
  61   { PPPOE_PADI, "PADI"},
  62   { PPPOE_PADO, "PADO"},
  63   { PPPOE_PADR, "PADR"},
  64   { PPPOE_PADS, "PADS"},
  65   { PPPOE_PADT, "PADT"},
  66   { 0, ""}, /* PPP Data */
  67   { 0, NULL }
  68 };
  69
  70 /* Tags */
  71 enum {
  72   PPPOE_EOL = 0,
  73   PPPOE_SERVICE_NAME = 0x0101,
  74   PPPOE_AC_NAME = 0x0102,
  75   PPPOE_HOST_UNIQ = 0x0103,
  76   PPPOE_AC_COOKIE = 0x0104,
  77   PPPOE_VENDOR = 0x0105,
  78   PPPOE_RELAY_SID = 0x0110,
  79   PPPOE_SERVICE_NAME_ERROR = 0x0201,
  80   PPPOE_AC_SYSTEM_ERROR = 0x0202,
  81   PPPOE_GENERIC_ERROR = 0x0203
  82 };
  83
  84 static struct tok pppoetag2str[] = {
  85   { PPPOE_EOL, "EOL"},
  86   { PPPOE_SERVICE_NAME, "Service-Name" },
  87   { PPPOE_AC_NAME, "AC-Name" },
  88   { PPPOE_HOST_UNIQ, "Host-Uniq" },
  89   { PPPOE_AC_COOKIE, "AC-Cookie" },
  90   { PPPOE_VENDOR, "Vendor-Specific" },
  91   { PPPOE_RELAY_SID, "Relay-Session-ID" },
  92   { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" },
  93   { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" },
  94   { PPPOE_GENERIC_ERROR, "Generic-Error" },
  95   { 0, NULL}
  96 };
  97
  98 #define PPPOE_HDRLEN 6
  99
 100 void
 101 pppoe_print(register const u_char *bp, u_int length)
 102 {
 103   register const struct ether_header *eh;
 104   register u_short pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid, pppoe_length;
 105   const u_char *pppoe_packet, *pppoe_payload;
 106
 107   eh = (struct ether_header *)packetp;
 108   pppoe_packet = packetp+sizeof(struct ether_header);
 109   if (pppoe_packet > snapend) {
 110     printf("[|pppoe]");
 111     return;
 112   }
 113
 114   pppoe_ver  = (pppoe_packet[0]&0xF0)>>4;
 115   pppoe_type  = (pppoe_packet[0]&0x0F);
 116   pppoe_code = (pppoe_packet[1]);
 117   pppoe_sessionid = (EXTRACT_16BITS(pppoe_packet+2));
 118   pppoe_length    = (EXTRACT_16BITS(pppoe_packet+4));
 119   pppoe_payload = pppoe_packet+6;
 120
 121   if (snapend < pppoe_payload) {
 122     printf(" truncated PPPoE");
 123     return;
 124   }
 125
 126   if (pppoe_ver != 1) {
 127     printf(" [ver %d]",pppoe_ver);
 128   }
 129   if (pppoe_type != 1) {
 130     printf(" [type %d]",pppoe_type);
 131   }
 132
 133   printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
 134   if (pppoe_code == PPPOE_PADI && pppoe_length > 1484-PPPOE_HDRLEN) {
 135     printf(" [len %d!]",pppoe_length);
 136   }
 137   if (pppoe_sessionid) {
 138     printf(" [ses 0x%x]",pppoe_sessionid);
 139   }
 140
 141   if (pppoe_payload + pppoe_length < snapend) {
 142     /*
 143     printf(" [length %d (%d extra bytes)]", pppoe_length, snapend-pppoe_payload-pppoe_length);
 144     {
 145       const u_char *x = pppoe_payload+pppoe_length;
 146       default_print(x, snapend - x);
 147     }
 148     */
 149     snapend = pppoe_payload+pppoe_length;
 150   }
 151
 152
 153   if (pppoe_code) {
 154     /* PPP session packets don't contain tags */
 155     u_short tag_type = -1, tag_len;
 156     const u_char *p = pppoe_payload;
 157
 158     /* loop invariant:
 159        p points to next tag,
 160        tag_type is previous tag or -1 for first iteration
 161     */
 162     while (tag_type &&
 163            p+4 < pppoe_payload + length &&
 164            p+4 < snapend) {
 165       tag_type = EXTRACT_16BITS(p);
 166       tag_len  = EXTRACT_16BITS(p+2);
 167       p += 4;
 168       /* p points to tag_value */
 169
 170       if (tag_len) {
 171         int isascii = 1;
 172         const u_char *v = p;
 173
 174         for (v=p; v<p+tag_len; v++)
 175           if (*v >= 127 || *v < 32) {
 176             isascii = 0;
 177             break;
 178           }
 179
 180         /* TODO print UTF8 decoded text */
 181         if (isascii)
 182           printf(" [%s \"%*.*s\"]",
 183                  tok2str(pppoetag2str, "TAG-0x%x", tag_type),
 184                  tag_len < 80 ? tag_len : 80,
 185                  tag_len < 80 ? tag_len : 80,
 186                  p
 187                  );
 188         else
 189           printf(" [%s UTF8]", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
 190       } else
 191         printf(" [%s]", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
 192
 193       p += tag_len;
 194       /* p points to next tag */
 195     }
 196   } else {
 197     u_short ptype;
 198     if (pppoe_payload[0] & 0x1) {
 199       ptype = pppoe_payload[0];
 200       pppoe_payload +=1;
 201       pppoe_length  -=1;
 202     } else if (pppoe_payload[1] & 0x1) {
 203       ptype = ntohs(*(u_short *)pppoe_payload);
 204       pppoe_payload +=2;
 205       pppoe_length  -=2;
 206     } else {
 207       printf(" Invalid PPP protocol ID: %x %x", pppoe_payload[0],pppoe_payload[1]);
 208       return;
 209     }
 210     printf(" ");
 211     if (ptype == PPP_IP)
 212       ip_print(pppoe_payload, pppoe_length);
 213     else if (ptype == PPP_LCP)
 214       lcp_print(pppoe_payload, pppoe_length);
 215     else
 216       printf("%s ", tok2str(ppptype2str, "proto-0x%x", ptype));
 217   }
 218   return;
 219 }