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 1.3 1999-12-15 00:23:06 fenner 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 #if __STDC__
  36 struct mbuf;
  37 struct rtentry;
  38 #endif
  39 #include <net/if.h>
  40
  41 #include <netinet/in.h>
  42 #include <netinet/if_ether.h>
  43
  44 #ifdef HAVE_MEMORY_H
  45 #include <memory.h>
  46 #endif
  47 #include <stdio.h>
  48 #include <string.h>
  49
  50 #include "interface.h"
  51 #include "addrtoname.h"
  52 #include "ppp.h"
  53 #include "ethertype.h"
  54 #include "extract.h"                    /* must come after interface.h */
  55
  56 /* Codes */
  57 enum {
  58   PPPOE_PADI = 0x09,
  59   PPPOE_PADO = 0x07,
  60   PPPOE_PADR = 0x19,
  61   PPPOE_PADS = 0x65,
  62   PPPOE_PADT = 0xa7
  63 };
  64
  65 static struct tok pppoecode2str[] = {
  66   { PPPOE_PADI, "PADI"},
  67   { PPPOE_PADO, "PADO"},
  68   { PPPOE_PADR, "PADR"},
  69   { PPPOE_PADS, "PADS"},
  70   { PPPOE_PADT, "PADT"},
  71   { 0, ""}, /* PPP Data */
  72   { 0, NULL }
  73 };
  74
  75 /* Tags */
  76 enum {
  77   PPPOE_EOL = 0,
  78   PPPOE_SERVICE_NAME = 0x0101,
  79   PPPOE_AC_NAME = 0x0102,
  80   PPPOE_HOST_UNIQ = 0x0103,
  81   PPPOE_AC_COOKIE = 0x0104,
  82   PPPOE_VENDOR = 0x0105,
  83   PPPOE_RELAY_SID = 0x0110,
  84   PPPOE_SERVICE_NAME_ERROR = 0x0201,
  85   PPPOE_AC_SYSTEM_ERROR = 0x0202,
  86   PPPOE_GENERIC_ERROR = 0x0203,
  87 };
  88
  89 static struct tok pppoetag2str[] = {
  90   { PPPOE_EOL, "EOL"},
  91   { PPPOE_SERVICE_NAME, "Service-Name" },
  92   { PPPOE_AC_NAME, "AC-Name" },
  93   { PPPOE_HOST_UNIQ, "Host-Uniq" },
  94   { PPPOE_AC_COOKIE, "AC-Cookie" },
  95   { PPPOE_VENDOR, "Vendor-Specific" },
  96   { PPPOE_RELAY_SID, "Relay-Session-ID" },
  97   { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" },
  98   { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" },
  99   { PPPOE_GENERIC_ERROR, "Generic-Error" },
 100   { 0, NULL}
 101 };
 102
 103 #define PPPOE_HDRLEN 6
 104
 105 void
 106 pppoe_print(register const u_char *bp, u_int length)
 107 {
 108   register const struct ether_header *eh;
 109   register u_short pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid, pppoe_length;
 110   const u_char *pppoe_packet, *pppoe_payload;
 111
 112   eh = (struct ether_header *)packetp;
 113   pppoe_packet = packetp+sizeof(struct ether_header);
 114   if (pppoe_packet > snapend) {
 115     printf("[|pppoe]");
 116     return;
 117   }
 118
 119   pppoe_ver  = (pppoe_packet[0]&0xF0)>>4;
 120   pppoe_type  = (pppoe_packet[0]&0x0F);
 121   pppoe_code = (pppoe_packet[1]);
 122   pppoe_sessionid = (EXTRACT_16BITS(pppoe_packet+2));
 123   pppoe_length    = (EXTRACT_16BITS(pppoe_packet+4));
 124   pppoe_payload = pppoe_packet+6;
 125
 126   if (snapend < pppoe_payload) {
 127     printf(" truncated PPPoE");
 128     return;
 129   }
 130
 131   if (pppoe_ver != 1) {
 132     printf(" [ver %d]",pppoe_ver);
 133   }
 134   if (pppoe_type != 1) {
 135     printf(" [type %d]",pppoe_type);
 136   }
 137
 138   printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
 139   if (pppoe_code == PPPOE_PADI && pppoe_length > 1484-PPPOE_HDRLEN) {
 140     printf(" [len %d!]",pppoe_length);
 141   }
 142   if (pppoe_sessionid) {
 143     printf(" [ses 0x%x]",pppoe_sessionid);
 144   }
 145
 146   if (pppoe_payload + pppoe_length < snapend) {
 147     /*
 148     printf(" [length %d (%d extra bytes)]", pppoe_length, snapend-pppoe_payload-pppoe_length);
 149     {
 150       const u_char *x = pppoe_payload+pppoe_length;
 151       default_print(x, snapend - x);
 152     }
 153     */
 154     snapend = pppoe_payload+pppoe_length;
 155   }
 156
 157
 158   if (pppoe_code) {
 159     /* PPP session packets don't contain tags */
 160     u_short tag_type = -1, tag_len;
 161     const u_char *p = pppoe_payload;
 162
 163     /* loop invariant:
 164        p points to next tag,
 165        tag_type is previous tag or -1 for first iteration
 166     */
 167     while (tag_type &&
 168            p+4 < pppoe_payload + length &&
 169            p+4 < snapend) {
 170       tag_type = EXTRACT_16BITS(p);
 171       tag_len  = EXTRACT_16BITS(p+2);
 172       p += 4;
 173       /* p points to tag_value */
 174
 175       if (tag_len) {
 176         int isascii = 1;
 177         const u_char *v = p;
 178
 179         for (v=p; v<p+tag_len; v++)
 180           if (*v >= 127 || *v < 32) {
 181             isascii = 0;
 182             break;
 183           }
 184
 185         /* TODO print UTF8 decoded text */
 186         if (isascii)
 187           printf(" [%s \"%*.*s\"]",
 188                  tok2str(pppoetag2str, "TAG-0x%x", tag_type),
 189                  tag_len < 80 ? tag_len : 80,
 190                  tag_len < 80 ? tag_len : 80,
 191                  p
 192                  );
 193         else
 194           printf(" [%s UTF8]", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
 195       } else
 196         printf(" [%s]", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
 197
 198       p += tag_len;
 199       /* p points to next tag */
 200     }
 201   } else {
 202     u_short ptype;
 203     if (pppoe_payload[0] & 0x1) {
 204       ptype = pppoe_payload[0];
 205       pppoe_payload +=1;
 206       pppoe_length  -=1;
 207     } else if (pppoe_payload[1] & 0x1) {
 208       ptype = ntohs(*(u_short *)pppoe_payload);
 209       pppoe_payload +=2;
 210       pppoe_length  -=2;
 211     } else {
 212       printf(" Invalid PPP protocol ID: %x %x", pppoe_payload[0],pppoe_payload[1]);
 213       return;
 214     }
 215     printf(" ");
 216     if (ptype == PPP_IP)
 217       ip_print(pppoe_payload, pppoe_length);
 218     else if (ptype == PPP_LCP)
 219       lcp_print(pppoe_payload, pppoe_length);
 220     else
 221       printf("%s ", tok2str(ppptype2str, "proto-0x%x", ptype));
 222   }
 223   return;
 224 }