dist/tcpdump/print-pppoe.c

   1 /*      $NetBSD$        */
   2
   3 /*
   4  * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that: (1) source code distributions
   9  * retain the above copyright notice and this paragraph in its entirety, (2)
  10  * distributions including binary code include the above copyright notice and
  11  * this paragraph in its entirety in the documentation or other materials
  12  * provided with the distribution, and (3) all advertising materials mentioning
  13  * features or use of this software display the following acknowledgement:
  14  * ``This product includes software developed by the University of California,
  15  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  16  * the University nor the names of its contributors may be used to endorse
  17  * or promote products derived from this software without specific prior
  18  * written permission.
  19  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  20  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  21  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  22  *
  23  * Original code by Greg Stark <gsstark@mit.edu>
  24  */
  25
  26 #include <sys/cdefs.h>
  27 #ifndef lint
  28 #if 0
  29 static const char rcsid[] _U_ =
  30 "@(#) Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.30.2.1 2005/04/26 19:48:56 guy Exp (LBL)";
  31 #else
  32 __RCSID("$NetBSD: tcpdump2rcsid.ex,v 1.1 2001/06/25 20:09:58 itojun Exp $");
  33 #endif
  34 #endif
  35
  36 #ifdef HAVE_CONFIG_H
  37 #include "config.h"
  38 #endif
  39
  40 #include <tcpdump-stdinc.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 "ether.h"
  50 #include "extract.h"                    /* must come after interface.h */
  51
  52 /* Codes */
  53 enum {
  54         PPPOE_PADI = 0x09,
  55         PPPOE_PADO = 0x07,
  56         PPPOE_PADR = 0x19,
  57         PPPOE_PADS = 0x65,
  58         PPPOE_PADT = 0xa7
  59 };
  60
  61 static struct tok pppoecode2str[] = {
  62         { PPPOE_PADI, "PADI" },
  63         { PPPOE_PADO, "PADO" },
  64         { PPPOE_PADR, "PADR" },
  65         { PPPOE_PADS, "PADS" },
  66         { PPPOE_PADT, "PADT" },
  67         { 0, "" }, /* PPP Data */
  68         { 0, NULL }
  69 };
  70
  71 /* Tags */
  72 enum {
  73         PPPOE_EOL = 0,
  74         PPPOE_SERVICE_NAME = 0x0101,
  75         PPPOE_AC_NAME = 0x0102,
  76         PPPOE_HOST_UNIQ = 0x0103,
  77         PPPOE_AC_COOKIE = 0x0104,
  78         PPPOE_VENDOR = 0x0105,
  79         PPPOE_RELAY_SID = 0x0110,
  80         PPPOE_SERVICE_NAME_ERROR = 0x0201,
  81         PPPOE_AC_SYSTEM_ERROR = 0x0202,
  82         PPPOE_GENERIC_ERROR = 0x0203
  83 };
  84
  85 static struct tok pppoetag2str[] = {
  86         { PPPOE_EOL, "EOL" },
  87         { PPPOE_SERVICE_NAME, "Service-Name" },
  88         { PPPOE_AC_NAME, "AC-Name" },
  89         { PPPOE_HOST_UNIQ, "Host-Uniq" },
  90         { PPPOE_AC_COOKIE, "AC-Cookie" },
  91         { PPPOE_VENDOR, "Vendor-Specific" },
  92         { PPPOE_RELAY_SID, "Relay-Session-ID" },
  93         { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" },
  94         { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" },
  95         { PPPOE_GENERIC_ERROR, "Generic-Error" },
  96         { 0, NULL }
  97 };
  98
  99 #define PPPOE_HDRLEN 6
 100 #define MAXTAGPRINT 80
 101
 102 u_int
 103 pppoe_if_print(const struct pcap_pkthdr *h, register const u_char *p)
 104 {
 105         return (pppoe_print(p, h->len));
 106 }
 107
 108 u_int
 109 pppoe_print(register const u_char *bp, u_int length)
 110 {
 111         u_int16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid;
 112         u_int pppoe_length;
 113         const u_char *pppoe_packet, *pppoe_payload;
 114
 115         if (length < PPPOE_HDRLEN) {
 116                 (void)printf("truncated-pppoe %u", length);
 117                 return (length);
 118         }
 119         length -= PPPOE_HDRLEN;
 120         pppoe_packet = bp;
 121         TCHECK2(*pppoe_packet, PPPOE_HDRLEN);
 122         pppoe_ver  = (pppoe_packet[0] & 0xF0) >> 4;
 123         pppoe_type  = (pppoe_packet[0] & 0x0F);
 124         pppoe_code = pppoe_packet[1];
 125         pppoe_sessionid = EXTRACT_16BITS(pppoe_packet + 2);
 126         pppoe_length    = EXTRACT_16BITS(pppoe_packet + 4);
 127         pppoe_payload = pppoe_packet + PPPOE_HDRLEN;
 128
 129         if (pppoe_ver != 1) {
 130                 printf(" [ver %d]",pppoe_ver);
 131         }
 132         if (pppoe_type != 1) {
 133                 printf(" [type %d]",pppoe_type);
 134         }
 135
 136         printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
 137         if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {
 138                 printf(" [len %u!]",pppoe_length);
 139         }
 140         if (pppoe_length > length) {
 141                 printf(" [len %u > %u!]", pppoe_length, length);
 142                 pppoe_length = length;
 143         }
 144         if (pppoe_sessionid) {
 145                 printf(" [ses 0x%x]", pppoe_sessionid);
 146         }
 147
 148         if (pppoe_code) {
 149                 /* PPP session packets don't contain tags */
 150                 u_short tag_type = 0xffff, tag_len;
 151                 const u_char *p = pppoe_payload;
 152
 153                 /*
 154                  * loop invariant:
 155                  * p points to current tag,
 156                  * tag_type is previous tag or 0xffff for first iteration
 157                  */
 158                 while (tag_type && p < pppoe_payload + pppoe_length) {
 159                         TCHECK2(*p, 4);
 160                         tag_type = EXTRACT_16BITS(p);
 161                         tag_len = EXTRACT_16BITS(p + 2);
 162                         p += 4;
 163                         /* p points to tag_value */
 164
 165                         if (tag_len) {
 166                                 unsigned isascii = 0, isgarbage = 0;
 167                                 const u_char *v = p;
 168                                 char tag_str[MAXTAGPRINT];
 169                                 unsigned tag_str_len = 0;
 170
 171                                 /* TODO print UTF-8 decoded text */
 172                                 TCHECK2(*p, tag_len);
 173                                 for (v = p; v < p + tag_len && tag_str_len < MAXTAGPRINT-1; v++)
 174                                         if (*v >= 32 && *v < 127) {
 175                                                 tag_str[tag_str_len++] = *v;
 176                                                 isascii++;
 177                                         } else {
 178                                                 tag_str[tag_str_len++] = '.';
 179                                                 isgarbage++;
 180                                         }
 181                                 tag_str[tag_str_len] = 0;
 182
 183                                 if (isascii > isgarbage) {
 184                                         printf(" [%s \"%*.*s\"]",
 185                                                tok2str(pppoetag2str, "TAG-0x%x", tag_type),
 186                                                (int)tag_str_len,
 187                                                (int)tag_str_len,
 188                                                tag_str);
 189                                 } else {
 190                                         /* Print hex, not fast to abuse printf but this doesn't get used much */
 191                                         printf(" [%s 0x", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
 192                                         for (v=p; v<p+tag_len; v++) {
 193                                                 printf("%02X", *v);
 194                                         }
 195                                         printf("]");
 196                                 }
 197
 198
 199                         } else
 200                                 printf(" [%s]", tok2str(pppoetag2str,
 201                                     "TAG-0x%x", tag_type));
 202
 203                         p += tag_len;
 204                         /* p points to next tag */
 205                 }
 206                 return (0);
 207         } else {
 208                 /* PPPoE data */
 209                 printf(" ");
 210                 return (PPPOE_HDRLEN + ppp_print(pppoe_payload, pppoe_length));
 211         }
 212
 213 trunc:
 214         printf("[|pppoe]");
 215         return (PPPOE_HDRLEN);
 216 }