1 /*
2 * Copyright (c) 1990, 1991, 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 #include <sys/cdefs.h>
23 #ifndef lint
24 __RCSID("$NetBSD: print-chdlc.c,v 1.6 2015/03/31 21:59:35 christos Exp $");
25 #endif
26
27 #define NETDISSECT_REWORKED
28 #ifdef HAVE_CONFIG_H
29 #include "config.h"
30 #endif
31
32 #include <tcpdump-stdinc.h>
33
34 #include "interface.h"
35 #include "addrtoname.h"
36 #include "ethertype.h"
37 #include "extract.h"
38 #include "chdlc.h"
39
40 static void chdlc_slarp_print(netdissect_options *, const u_char *, u_int);
41
42 static const struct tok chdlc_cast_values[] = {
43 { CHDLC_UNICAST, "unicast" },
44 { CHDLC_BCAST, "bcast" },
45 { 0, NULL}
46 };
47
48
49 /* Standard CHDLC printer */
50 u_int
chdlc_if_print(netdissect_options * ndo,const struct pcap_pkthdr * h,register const u_char * p)51 chdlc_if_print(netdissect_options *ndo, const struct pcap_pkthdr *h, register const u_char *p)
52 {
53 register u_int length = h->len;
54 register u_int caplen = h->caplen;
55
56 if (caplen < CHDLC_HDRLEN) {
57 ND_PRINT((ndo, "[|chdlc]"));
58 return (caplen);
59 }
60 return (chdlc_print(ndo, p,length));
61 }
62
63 u_int
chdlc_print(netdissect_options * ndo,register const u_char * p,u_int length)64 chdlc_print(netdissect_options *ndo, register const u_char *p, u_int length)
65 {
66 u_int proto;
67
68 proto = EXTRACT_16BITS(&p[2]);
69 if (ndo->ndo_eflag) {
70 ND_PRINT((ndo, "%s, ethertype %s (0x%04x), length %u: ",
71 tok2str(chdlc_cast_values, "0x%02x", p[0]),
72 tok2str(ethertype_values, "Unknown", proto),
73 proto,
74 length));
75 }
76
77 length -= CHDLC_HDRLEN;
78 p += CHDLC_HDRLEN;
79
80 switch (proto) {
81 case ETHERTYPE_IP:
82 ip_print(ndo, p, length);
83 break;
84 case ETHERTYPE_IPV6:
85 ip6_print(ndo, p, length);
86 break;
87 case CHDLC_TYPE_SLARP:
88 chdlc_slarp_print(ndo, p, length);
89 break;
90 #if 0
91 case CHDLC_TYPE_CDP:
92 chdlc_cdp_print(p, length);
93 break;
94 #endif
95 case ETHERTYPE_MPLS:
96 case ETHERTYPE_MPLS_MULTI:
97 mpls_print(ndo, p, length);
98 break;
99 case ETHERTYPE_ISO:
100 /* is the fudge byte set ? lets verify by spotting ISO headers */
101 if (*(p+1) == 0x81 ||
102 *(p+1) == 0x82 ||
103 *(p+1) == 0x83)
104 isoclns_print(ndo, p + 1, length - 1, length - 1);
105 else
106 isoclns_print(ndo, p, length, length);
107 break;
108 default:
109 if (!ndo->ndo_eflag)
110 ND_PRINT((ndo, "unknown CHDLC protocol (0x%04x)", proto));
111 break;
112 }
113
114 return (CHDLC_HDRLEN);
115 }
116
117 /*
118 * The fixed-length portion of a SLARP packet.
119 */
120 struct cisco_slarp {
121 uint8_t code[4];
122 #define SLARP_REQUEST 0
123 #define SLARP_REPLY 1
124 #define SLARP_KEEPALIVE 2
125 union {
126 struct {
127 uint8_t addr[4];
128 uint8_t mask[4];
129 } addr;
130 struct {
131 uint8_t myseq[4];
132 uint8_t yourseq[4];
133 uint8_t rel[2];
134 } keep;
135 } un;
136 };
137
138 #define SLARP_MIN_LEN 14
139 #define SLARP_MAX_LEN 18
140
141 static void
chdlc_slarp_print(netdissect_options * ndo,const u_char * cp,u_int length)142 chdlc_slarp_print(netdissect_options *ndo, const u_char *cp, u_int length)
143 {
144 const struct cisco_slarp *slarp;
145 u_int sec,min,hrs,days;
146
147 ND_PRINT((ndo, "SLARP (length: %u), ",length));
148 if (length < SLARP_MIN_LEN)
149 goto trunc;
150
151 slarp = (const struct cisco_slarp *)cp;
152 ND_TCHECK2(*slarp, SLARP_MIN_LEN);
153 switch (EXTRACT_32BITS(&slarp->code)) {
154 case SLARP_REQUEST:
155 ND_PRINT((ndo, "request"));
156 /*
157 * At least according to William "Chops" Westfield's
158 * message in
159 *
160 * http://www.nethelp.no/net/cisco-hdlc.txt
161 *
162 * the address and mask aren't used in requests -
163 * they're just zero.
164 */
165 break;
166 case SLARP_REPLY:
167 ND_PRINT((ndo, "reply %s/%s",
168 ipaddr_string(ndo, &slarp->un.addr.addr),
169 ipaddr_string(ndo, &slarp->un.addr.mask)));
170 break;
171 case SLARP_KEEPALIVE:
172 ND_PRINT((ndo, "keepalive: mineseen=0x%08x, yourseen=0x%08x, reliability=0x%04x",
173 EXTRACT_32BITS(&slarp->un.keep.myseq),
174 EXTRACT_32BITS(&slarp->un.keep.yourseq),
175 EXTRACT_16BITS(&slarp->un.keep.rel)));
176
177 if (length >= SLARP_MAX_LEN) { /* uptime-stamp is optional */
178 cp += SLARP_MIN_LEN;
179 ND_TCHECK2(*cp, 4);
180 sec = EXTRACT_32BITS(cp) / 1000;
181 min = sec / 60; sec -= min * 60;
182 hrs = min / 60; min -= hrs * 60;
183 days = hrs / 24; hrs -= days * 24;
184 ND_PRINT((ndo, ", link uptime=%ud%uh%um%us",days,hrs,min,sec));
185 }
186 break;
187 default:
188 ND_PRINT((ndo, "0x%02x unknown", EXTRACT_32BITS(&slarp->code)));
189 if (ndo->ndo_vflag <= 1)
190 print_unknown_data(ndo,cp+4,"\n\t",length-4);
191 break;
192 }
193
194 if (SLARP_MAX_LEN < length && ndo->ndo_vflag)
195 ND_PRINT((ndo, ", (trailing junk: %d bytes)", length - SLARP_MAX_LEN));
196 if (ndo->ndo_vflag > 1)
197 print_unknown_data(ndo,cp+4,"\n\t",length-4);
198 return;
199
200 trunc:
201 ND_PRINT((ndo, "[|slarp]"));
202 }
203
204
205 /*
206 * Local Variables:
207 * c-style: whitesmith
208 * c-basic-offset: 8
209 * End:
210 */
211