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 * Original code by Greg Stark <gsstark@mit.edu>
22 */
23
24 #ifndef lint
25 static const char rcsid[] _U_ =
26 "@(#) $Header: /tcpdump/master/tcpdump/print-pppoe.c,v 1.30.2.1 2005/04/26 19:48:56 guy Exp $ (LBL)";
27 #endif
28
29 #ifdef HAVE_CONFIG_H
30 #include "config.h"
31 #endif
32
33 #include <tcpdump-stdinc.h>
34
35 #include <stdio.h>
36 #include <string.h>
37
38 #include "interface.h"
39 #include "addrtoname.h"
40 #include "ppp.h"
41 #include "ethertype.h"
42 #include "ether.h"
43 #include "extract.h" /* must come after interface.h */
44
45 /* Codes */
46 enum {
47 PPPOE_PADI = 0x09,
48 PPPOE_PADO = 0x07,
49 PPPOE_PADR = 0x19,
50 PPPOE_PADS = 0x65,
51 PPPOE_PADT = 0xa7
52 };
53
54 static struct tok pppoecode2str[] = {
55 { PPPOE_PADI, "PADI" },
56 { PPPOE_PADO, "PADO" },
57 { PPPOE_PADR, "PADR" },
58 { PPPOE_PADS, "PADS" },
59 { PPPOE_PADT, "PADT" },
60 { 0, "" }, /* PPP Data */
61 { 0, NULL }
62 };
63
64 /* Tags */
65 enum {
66 PPPOE_EOL = 0,
67 PPPOE_SERVICE_NAME = 0x0101,
68 PPPOE_AC_NAME = 0x0102,
69 PPPOE_HOST_UNIQ = 0x0103,
70 PPPOE_AC_COOKIE = 0x0104,
71 PPPOE_VENDOR = 0x0105,
72 PPPOE_RELAY_SID = 0x0110,
73 PPPOE_SERVICE_NAME_ERROR = 0x0201,
74 PPPOE_AC_SYSTEM_ERROR = 0x0202,
75 PPPOE_GENERIC_ERROR = 0x0203
76 };
77
78 static struct tok pppoetag2str[] = {
79 { PPPOE_EOL, "EOL" },
80 { PPPOE_SERVICE_NAME, "Service-Name" },
81 { PPPOE_AC_NAME, "AC-Name" },
82 { PPPOE_HOST_UNIQ, "Host-Uniq" },
83 { PPPOE_AC_COOKIE, "AC-Cookie" },
84 { PPPOE_VENDOR, "Vendor-Specific" },
85 { PPPOE_RELAY_SID, "Relay-Session-ID" },
86 { PPPOE_SERVICE_NAME_ERROR, "Service-Name-Error" },
87 { PPPOE_AC_SYSTEM_ERROR, "AC-System-Error" },
88 { PPPOE_GENERIC_ERROR, "Generic-Error" },
89 { 0, NULL }
90 };
91
92 #define PPPOE_HDRLEN 6
93 #define MAXTAGPRINT 80
94
95 u_int
pppoe_if_print(const struct pcap_pkthdr * h,register const u_char * p)96 pppoe_if_print(const struct pcap_pkthdr *h, register const u_char *p)
97 {
98 return (pppoe_print(p, h->len));
99 }
100
101 u_int
pppoe_print(register const u_char * bp,u_int length)102 pppoe_print(register const u_char *bp, u_int length)
103 {
104 u_int16_t pppoe_ver, pppoe_type, pppoe_code, pppoe_sessionid;
105 u_int pppoe_length;
106 const u_char *pppoe_packet, *pppoe_payload;
107
108 if (length < PPPOE_HDRLEN) {
109 (void)printf("truncated-pppoe %u", length);
110 return (length);
111 }
112 length -= PPPOE_HDRLEN;
113 pppoe_packet = bp;
114 TCHECK2(*pppoe_packet, PPPOE_HDRLEN);
115 pppoe_ver = (pppoe_packet[0] & 0xF0) >> 4;
116 pppoe_type = (pppoe_packet[0] & 0x0F);
117 pppoe_code = pppoe_packet[1];
118 pppoe_sessionid = EXTRACT_16BITS(pppoe_packet + 2);
119 pppoe_length = EXTRACT_16BITS(pppoe_packet + 4);
120 pppoe_payload = pppoe_packet + PPPOE_HDRLEN;
121
122 if (pppoe_ver != 1) {
123 printf(" [ver %d]",pppoe_ver);
124 }
125 if (pppoe_type != 1) {
126 printf(" [type %d]",pppoe_type);
127 }
128
129 printf("PPPoE %s", tok2str(pppoecode2str, "PAD-%x", pppoe_code));
130 if (pppoe_code == PPPOE_PADI && pppoe_length > 1484 - PPPOE_HDRLEN) {
131 printf(" [len %u!]",pppoe_length);
132 }
133 if (pppoe_length > length) {
134 printf(" [len %u > %u!]", pppoe_length, length);
135 pppoe_length = length;
136 }
137 if (pppoe_sessionid) {
138 printf(" [ses 0x%x]", pppoe_sessionid);
139 }
140
141 if (pppoe_code) {
142 /* PPP session packets don't contain tags */
143 u_short tag_type = 0xffff, tag_len;
144 const u_char *p = pppoe_payload;
145
146 /*
147 * loop invariant:
148 * p points to current tag,
149 * tag_type is previous tag or 0xffff for first iteration
150 */
151 while (tag_type && p < pppoe_payload + pppoe_length) {
152 TCHECK2(*p, 4);
153 tag_type = EXTRACT_16BITS(p);
154 tag_len = EXTRACT_16BITS(p + 2);
155 p += 4;
156 /* p points to tag_value */
157
158 if (tag_len) {
159 unsigned isascii = 0, isgarbage = 0;
160 const u_char *v = p;
161 char tag_str[MAXTAGPRINT];
162 unsigned tag_str_len = 0;
163
164 /* TODO print UTF-8 decoded text */
165 TCHECK2(*p, tag_len);
166 for (v = p; v < p + tag_len && tag_str_len < MAXTAGPRINT-1; v++)
167 if (*v >= 32 && *v < 127) {
168 tag_str[tag_str_len++] = *v;
169 isascii++;
170 } else {
171 tag_str[tag_str_len++] = '.';
172 isgarbage++;
173 }
174 tag_str[tag_str_len] = 0;
175
176 if (isascii > isgarbage) {
177 printf(" [%s \"%*.*s\"]",
178 tok2str(pppoetag2str, "TAG-0x%x", tag_type),
179 (int)tag_str_len,
180 (int)tag_str_len,
181 tag_str);
182 } else {
183 /* Print hex, not fast to abuse printf but this doesn't get used much */
184 printf(" [%s 0x", tok2str(pppoetag2str, "TAG-0x%x", tag_type));
185 for (v=p; v<p+tag_len; v++) {
186 printf("%02X", *v);
187 }
188 printf("]");
189 }
190
191
192 } else
193 printf(" [%s]", tok2str(pppoetag2str,
194 "TAG-0x%x", tag_type));
195
196 p += tag_len;
197 /* p points to next tag */
198 }
199 return (0);
200 } else {
201 /* PPPoE data */
202 printf(" ");
203 return (PPPOE_HDRLEN + ppp_print(pppoe_payload, pppoe_length));
204 }
205
206 trunc:
207 printf("[|pppoe]");
208 return (PPPOE_HDRLEN);
209 }
210