xref: /netbsd-src/external/bsd/tcpdump/dist/print-ldp.c (revision cc576e1d8e4f4078fd4e81238abca9fca216f6ec)
1 /*
2  * Redistribution and use in source and binary forms, with or without
3  * modification, are permitted provided that: (1) source code
4  * distributions retain the above copyright notice and this paragraph
5  * in its entirety, and (2) distributions including binary code include
6  * the above copyright notice and this paragraph in its entirety in
7  * the documentation or other materials provided with the distribution.
8  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
9  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
10  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11  * FOR A PARTICULAR PURPOSE.
12  *
13  * Original code by Hannes Gredler (hannes@juniper.net)
14  *  and Steinar Haug (sthaug@nethelp.no)
15  */
16 
17 #include <sys/cdefs.h>
18 #ifndef lint
19 __RCSID("$NetBSD: print-ldp.c,v 1.7 2017/01/24 23:29:14 christos Exp $");
20 #endif
21 
22 #ifdef HAVE_CONFIG_H
23 #include "config.h"
24 #endif
25 
26 #include <netdissect-stdinc.h>
27 
28 #include "netdissect.h"
29 #include "extract.h"
30 #include "addrtoname.h"
31 
32 #include "l2vpn.h"
33 #include "af.h"
34 
35 /*
36  * ldp common header
37  *
38  *  0                   1                   2                   3
39  *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
40  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41  * |  Version                      |         PDU Length            |
42  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43  * |                         LDP Identifier                        |
44  * +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45  * |                               |
46  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47  *
48  */
49 
50 struct ldp_common_header {
51     uint8_t version[2];
52     uint8_t pdu_length[2];
53     uint8_t lsr_id[4];
54     uint8_t label_space[2];
55 };
56 
57 #define LDP_VERSION 1
58 
59 /*
60  * ldp message header
61  *
62  *  0                   1                   2                   3
63  *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
64  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65  * |U|   Message Type              |      Message Length           |
66  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67  * |                     Message ID                                |
68  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69  * |                                                               |
70  * +                                                               +
71  * |                     Mandatory Parameters                      |
72  * +                                                               +
73  * |                                                               |
74  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
75  * |                                                               |
76  * +                                                               +
77  * |                     Optional Parameters                       |
78  * +                                                               +
79  * |                                                               |
80  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
81  */
82 
83 struct ldp_msg_header {
84     uint8_t type[2];
85     uint8_t length[2];
86     uint8_t id[4];
87 };
88 
89 #define	LDP_MASK_MSG_TYPE(x)  ((x)&0x7fff)
90 #define	LDP_MASK_U_BIT(x)     ((x)&0x8000)
91 
92 #define	LDP_MSG_NOTIF                0x0001
93 #define	LDP_MSG_HELLO                0x0100
94 #define	LDP_MSG_INIT                 0x0200
95 #define	LDP_MSG_KEEPALIVE            0x0201
96 #define	LDP_MSG_ADDRESS              0x0300
97 #define	LDP_MSG_ADDRESS_WITHDRAW     0x0301
98 #define	LDP_MSG_LABEL_MAPPING        0x0400
99 #define	LDP_MSG_LABEL_REQUEST        0x0401
100 #define	LDP_MSG_LABEL_WITHDRAW       0x0402
101 #define	LDP_MSG_LABEL_RELEASE        0x0403
102 #define	LDP_MSG_LABEL_ABORT_REQUEST  0x0404
103 
104 #define	LDP_VENDOR_PRIVATE_MIN       0x3e00
105 #define	LDP_VENDOR_PRIVATE_MAX       0x3eff
106 #define	LDP_EXPERIMENTAL_MIN         0x3f00
107 #define	LDP_EXPERIMENTAL_MAX         0x3fff
108 
109 static const struct tok ldp_msg_values[] = {
110     { LDP_MSG_NOTIF,	             "Notification" },
111     { LDP_MSG_HELLO,	             "Hello" },
112     { LDP_MSG_INIT,	             "Initialization" },
113     { LDP_MSG_KEEPALIVE,             "Keepalive" },
114     { LDP_MSG_ADDRESS,	             "Address" },
115     { LDP_MSG_ADDRESS_WITHDRAW,	     "Address Withdraw" },
116     { LDP_MSG_LABEL_MAPPING,	     "Label Mapping" },
117     { LDP_MSG_LABEL_REQUEST,	     "Label Request" },
118     { LDP_MSG_LABEL_WITHDRAW,	     "Label Withdraw" },
119     { LDP_MSG_LABEL_RELEASE,	     "Label Release" },
120     { LDP_MSG_LABEL_ABORT_REQUEST,   "Label Abort Request" },
121     { 0, NULL}
122 };
123 
124 #define	LDP_MASK_TLV_TYPE(x)  ((x)&0x3fff)
125 #define	LDP_MASK_F_BIT(x) ((x)&0x4000)
126 
127 #define	LDP_TLV_FEC                  0x0100
128 #define	LDP_TLV_ADDRESS_LIST         0x0101
129 #define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
130 #define	LDP_TLV_HOP_COUNT            0x0103
131 #define	LDP_TLV_PATH_VECTOR          0x0104
132 #define	LDP_TLV_GENERIC_LABEL        0x0200
133 #define	LDP_TLV_ATM_LABEL            0x0201
134 #define	LDP_TLV_FR_LABEL             0x0202
135 #define	LDP_TLV_STATUS               0x0300
136 #define	LDP_TLV_EXTD_STATUS          0x0301
137 #define	LDP_TLV_RETURNED_PDU         0x0302
138 #define	LDP_TLV_RETURNED_MSG         0x0303
139 #define	LDP_TLV_COMMON_HELLO         0x0400
140 #define	LDP_TLV_IPV4_TRANSPORT_ADDR  0x0401
141 #define	LDP_TLV_CONFIG_SEQ_NUMBER    0x0402
142 #define	LDP_TLV_IPV6_TRANSPORT_ADDR  0x0403
143 #define	LDP_TLV_COMMON_SESSION       0x0500
144 #define	LDP_TLV_ATM_SESSION_PARM     0x0501
145 #define	LDP_TLV_FR_SESSION_PARM      0x0502
146 #define LDP_TLV_FT_SESSION	     0x0503
147 #define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
148 #define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
149 
150 static const struct tok ldp_tlv_values[] = {
151     { LDP_TLV_FEC,	             "FEC" },
152     { LDP_TLV_ADDRESS_LIST,          "Address List" },
153     { LDP_TLV_HOP_COUNT,             "Hop Count" },
154     { LDP_TLV_PATH_VECTOR,           "Path Vector" },
155     { LDP_TLV_GENERIC_LABEL,         "Generic Label" },
156     { LDP_TLV_ATM_LABEL,             "ATM Label" },
157     { LDP_TLV_FR_LABEL,              "Frame-Relay Label" },
158     { LDP_TLV_STATUS,                "Status" },
159     { LDP_TLV_EXTD_STATUS,           "Extended Status" },
160     { LDP_TLV_RETURNED_PDU,          "Returned PDU" },
161     { LDP_TLV_RETURNED_MSG,          "Returned Message" },
162     { LDP_TLV_COMMON_HELLO,          "Common Hello Parameters" },
163     { LDP_TLV_IPV4_TRANSPORT_ADDR,   "IPv4 Transport Address" },
164     { LDP_TLV_CONFIG_SEQ_NUMBER,     "Configuration Sequence Number" },
165     { LDP_TLV_IPV6_TRANSPORT_ADDR,   "IPv6 Transport Address" },
166     { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
167     { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
168     { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
169     { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
170     { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
171     { LDP_TLV_MTU,                   "MTU" },
172     { 0, NULL}
173 };
174 
175 #define LDP_FEC_WILDCARD	0x01
176 #define LDP_FEC_PREFIX		0x02
177 #define LDP_FEC_HOSTADDRESS	0x03
178 /* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
179 #define LDP_FEC_MARTINI_VC	0x80
180 
181 static const struct tok ldp_fec_values[] = {
182     { LDP_FEC_WILDCARD,		"Wildcard" },
183     { LDP_FEC_PREFIX,		"Prefix" },
184     { LDP_FEC_HOSTADDRESS,	"Host address" },
185     { LDP_FEC_MARTINI_VC,	"Martini VC" },
186     { 0, NULL}
187 };
188 
189 #define LDP_FEC_MARTINI_IFPARM_MTU  0x01
190 #define LDP_FEC_MARTINI_IFPARM_DESC 0x03
191 #define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
192 
193 static const struct tok ldp_fec_martini_ifparm_values[] = {
194     { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
195     { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
196     { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
197     { 0, NULL}
198 };
199 
200 /* draft-ietf-pwe3-vccv-04.txt */
201 static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
202     { 0x01, "PWE3 control word" },
203     { 0x02, "MPLS Router Alert Label" },
204     { 0x04, "MPLS inner label TTL = 1" },
205     { 0, NULL}
206 };
207 
208 /* draft-ietf-pwe3-vccv-04.txt */
209 static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
210     { 0x01, "ICMP Ping" },
211     { 0x02, "LSP Ping" },
212     { 0x04, "BFD" },
213     { 0, NULL}
214 };
215 
216 static int ldp_pdu_print(netdissect_options *, register const u_char *);
217 
218 /*
219  * ldp tlv header
220  *
221  *  0                   1                   2                   3
222  *  0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
223  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
224  * |U|F|        Type               |            Length             |
225  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
226  * |                                                               |
227  * |                             Value                             |
228  * ~                                                               ~
229  * |                                                               |
230  * |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
231  * |                               |
232  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
233  */
234 
235 #define TLV_TCHECK(minlen) \
236     ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
237 
238 static int
239 ldp_tlv_print(netdissect_options *ndo,
240               register const u_char *tptr,
241               u_short msg_tlen)
242 {
243     struct ldp_tlv_header {
244         uint8_t type[2];
245         uint8_t length[2];
246     };
247 
248     const struct ldp_tlv_header *ldp_tlv_header;
249     u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
250     u_char fec_type;
251     u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
252     char buf[100];
253     int i;
254 
255     ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
256     ND_TCHECK(*ldp_tlv_header);
257     tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
258     if (tlv_len + 4 > msg_tlen) {
259         ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
260         return 0;
261     }
262     tlv_tlen=tlv_len;
263     tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
264 
265     /* FIXME vendor private / experimental check */
266     ND_PRINT((ndo, "\n\t    %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
267            tok2str(ldp_tlv_values,
268                    "Unknown",
269                    tlv_type),
270            tlv_type,
271            tlv_len,
272            LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
273            LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
274 
275     tptr+=sizeof(struct ldp_tlv_header);
276 
277     switch(tlv_type) {
278 
279     case LDP_TLV_COMMON_HELLO:
280         TLV_TCHECK(4);
281         ND_PRINT((ndo, "\n\t      Hold Time: %us, Flags: [%s Hello%s]",
282                EXTRACT_16BITS(tptr),
283                (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
284                (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
285         break;
286 
287     case LDP_TLV_IPV4_TRANSPORT_ADDR:
288         TLV_TCHECK(4);
289         ND_PRINT((ndo, "\n\t      IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
290         break;
291     case LDP_TLV_IPV6_TRANSPORT_ADDR:
292         TLV_TCHECK(16);
293         ND_PRINT((ndo, "\n\t      IPv6 Transport Address: %s", ip6addr_string(ndo, tptr)));
294         break;
295     case LDP_TLV_CONFIG_SEQ_NUMBER:
296         TLV_TCHECK(4);
297         ND_PRINT((ndo, "\n\t      Sequence Number: %u", EXTRACT_32BITS(tptr)));
298         break;
299 
300     case LDP_TLV_ADDRESS_LIST:
301         TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
302 	af = EXTRACT_16BITS(tptr);
303 	tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
304         tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
305 	ND_PRINT((ndo, "\n\t      Address Family: %s, addresses",
306                tok2str(af_values, "Unknown (%u)", af)));
307         switch (af) {
308         case AFNUM_INET:
309 	    while(tlv_tlen >= sizeof(struct in_addr)) {
310 		ND_TCHECK2(*tptr, sizeof(struct in_addr));
311 		ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
312 		tlv_tlen-=sizeof(struct in_addr);
313 		tptr+=sizeof(struct in_addr);
314 	    }
315             break;
316         case AFNUM_INET6:
317 	    while(tlv_tlen >= sizeof(struct in6_addr)) {
318 		ND_TCHECK2(*tptr, sizeof(struct in6_addr));
319 		ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
320 		tlv_tlen-=sizeof(struct in6_addr);
321 		tptr+=sizeof(struct in6_addr);
322 	    }
323             break;
324         default:
325             /* unknown AF */
326             break;
327         }
328 	break;
329 
330     case LDP_TLV_COMMON_SESSION:
331 	TLV_TCHECK(8);
332 	ND_PRINT((ndo, "\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
333 	       EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
334 	       (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
335 	       (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
336 	       ));
337 	break;
338 
339     case LDP_TLV_FEC:
340         TLV_TCHECK(1);
341         fec_type = *tptr;
342 	ND_PRINT((ndo, "\n\t      %s FEC (0x%02x)",
343 	       tok2str(ldp_fec_values, "Unknown", fec_type),
344 	       fec_type));
345 
346 	tptr+=1;
347 	tlv_tlen-=1;
348 	switch(fec_type) {
349 
350 	case LDP_FEC_WILDCARD:
351 	    break;
352 	case LDP_FEC_PREFIX:
353 	    TLV_TCHECK(2);
354 	    af = EXTRACT_16BITS(tptr);
355 	    tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
356 	    tlv_tlen-=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
357 	    if (af == AFNUM_INET) {
358 		i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
359 		if (i == -2)
360 		    goto trunc;
361 		if (i == -3)
362 		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
363 		else if (i == -1)
364 		    ND_PRINT((ndo, ": IPv4 prefix (invalid length)"));
365 		else
366 		    ND_PRINT((ndo, ": IPv4 prefix %s", buf));
367 	    }
368 	    else if (af == AFNUM_INET6) {
369 		i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
370 		if (i == -2)
371 		    goto trunc;
372 		if (i == -3)
373 		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
374 		else if (i == -1)
375 		    ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
376 		else
377 		    ND_PRINT((ndo, ": IPv6 prefix %s", buf));
378 	    }
379 	    else
380 		ND_PRINT((ndo, ": Address family %u prefix", af));
381 	    break;
382 	case LDP_FEC_HOSTADDRESS:
383 	    break;
384 	case LDP_FEC_MARTINI_VC:
385             /*
386 	     * According to RFC 4908, the VC info Length field can be zero,
387 	     * in which case not only are there no interface parameters,
388 	     * there's no VC ID.
389 	     */
390             TLV_TCHECK(7);
391             vc_info_len = *(tptr+2);
392 
393             if (vc_info_len == 0) {
394                 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
395                        tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
396                        EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
397                        EXTRACT_32BITS(tptr+3),
398                        vc_info_len));
399                 break;
400             }
401 
402             /* Make sure we have the VC ID as well */
403             TLV_TCHECK(11);
404 	    ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
405 		   tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
406 		   EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
407                    EXTRACT_32BITS(tptr+3),
408 		   EXTRACT_32BITS(tptr+7),
409                    vc_info_len));
410             if (vc_info_len < 4) {
411                 /* minimum 4, for the VC ID */
412                 ND_PRINT((ndo, " (invalid, < 4"));
413                 return(tlv_len+4); /* Type & Length fields not included */
414 	    }
415             vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
416 
417             /* Skip past the fixed information and the VC ID */
418             tptr+=11;
419             tlv_tlen-=11;
420             TLV_TCHECK(vc_info_len);
421 
422             while (vc_info_len > 2) {
423                 vc_info_tlv_type = *tptr;
424                 vc_info_tlv_len = *(tptr+1);
425                 if (vc_info_tlv_len < 2)
426                     break;
427                 if (vc_info_len < vc_info_tlv_len)
428                     break;
429 
430                 ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
431                        tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
432                        vc_info_tlv_type,
433                        vc_info_tlv_len));
434 
435                 switch(vc_info_tlv_type) {
436                 case LDP_FEC_MARTINI_IFPARM_MTU:
437                     ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
438                     break;
439 
440                 case LDP_FEC_MARTINI_IFPARM_DESC:
441                     ND_PRINT((ndo, ": "));
442                     for (idx = 2; idx < vc_info_tlv_len; idx++)
443                         safeputchar(ndo, *(tptr + idx));
444                     break;
445 
446                 case LDP_FEC_MARTINI_IFPARM_VCCV:
447                     ND_PRINT((ndo, "\n\t\t  Control Channels (0x%02x) = [%s]",
448                            *(tptr+2),
449                            bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
450                     ND_PRINT((ndo, "\n\t\t  CV Types (0x%02x) = [%s]",
451                            *(tptr+3),
452                            bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
453                     break;
454 
455                 default:
456                     print_unknown_data(ndo, tptr+2, "\n\t\t  ", vc_info_tlv_len-2);
457                     break;
458                 }
459 
460                 vc_info_len -= vc_info_tlv_len;
461                 tptr += vc_info_tlv_len;
462             }
463 	    break;
464 	}
465 
466 	break;
467 
468     case LDP_TLV_GENERIC_LABEL:
469 	TLV_TCHECK(4);
470 	ND_PRINT((ndo, "\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
471 	break;
472 
473     case LDP_TLV_STATUS:
474 	TLV_TCHECK(8);
475 	ui = EXTRACT_32BITS(tptr);
476 	tptr+=4;
477 	ND_PRINT((ndo, "\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
478 	       ui&0x3fffffff,
479 	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
480 	       ui&0x40000000 ? "do" : "don't"));
481 	ui = EXTRACT_32BITS(tptr);
482 	tptr+=4;
483 	if (ui)
484 	    ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
485 	break;
486 
487     case LDP_TLV_FT_SESSION:
488 	TLV_TCHECK(8);
489 	ft_flags = EXTRACT_16BITS(tptr);
490 	ND_PRINT((ndo, "\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
491 	       ft_flags&0x8000 ? "" : "No ",
492 	       ft_flags&0x8 ? "" : "Don't ",
493 	       ft_flags&0x4 ? "" : "No ",
494 	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
495 	       ft_flags&0x1 ? "" : "Don't "));
496 	tptr+=4;
497 	ui = EXTRACT_32BITS(tptr);
498 	if (ui)
499 	    ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
500 	tptr+=4;
501 	ui = EXTRACT_32BITS(tptr);
502 	if (ui)
503 	    ND_PRINT((ndo, ", Recovery Time: %ums", ui));
504 	break;
505 
506     case LDP_TLV_MTU:
507 	TLV_TCHECK(2);
508 	ND_PRINT((ndo, "\n\t      MTU: %u", EXTRACT_16BITS(tptr)));
509 	break;
510 
511 
512     /*
513      *  FIXME those are the defined TLVs that lack a decoder
514      *  you are welcome to contribute code ;-)
515      */
516 
517     case LDP_TLV_HOP_COUNT:
518     case LDP_TLV_PATH_VECTOR:
519     case LDP_TLV_ATM_LABEL:
520     case LDP_TLV_FR_LABEL:
521     case LDP_TLV_EXTD_STATUS:
522     case LDP_TLV_RETURNED_PDU:
523     case LDP_TLV_RETURNED_MSG:
524     case LDP_TLV_ATM_SESSION_PARM:
525     case LDP_TLV_FR_SESSION_PARM:
526     case LDP_TLV_LABEL_REQUEST_MSG_ID:
527 
528     default:
529         if (ndo->ndo_vflag <= 1)
530             print_unknown_data(ndo, tptr, "\n\t      ", tlv_tlen);
531         break;
532     }
533     return(tlv_len+4); /* Type & Length fields not included */
534 
535 trunc:
536     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
537     return 0;
538 
539 badtlv:
540     ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
541     return(tlv_len+4); /* Type & Length fields not included */
542 }
543 
544 void
545 ldp_print(netdissect_options *ndo,
546           register const u_char *pptr, register u_int len)
547 {
548     int processed;
549     while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
550         processed = ldp_pdu_print(ndo, pptr);
551         if (processed == 0)
552             return;
553         len -= processed;
554         pptr += processed;
555     }
556 }
557 
558 static int
559 ldp_pdu_print(netdissect_options *ndo,
560               register const u_char *pptr)
561 {
562     const struct ldp_common_header *ldp_com_header;
563     const struct ldp_msg_header *ldp_msg_header;
564     const u_char *tptr,*msg_tptr;
565     u_short tlen;
566     u_short pdu_len,msg_len,msg_type,msg_tlen;
567     int hexdump,processed;
568 
569     ldp_com_header = (const struct ldp_common_header *)pptr;
570     ND_TCHECK(*ldp_com_header);
571 
572     /*
573      * Sanity checking of the header.
574      */
575     if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
576 	ND_PRINT((ndo, "%sLDP version %u packet not supported",
577                (ndo->ndo_vflag < 1) ? "" : "\n\t",
578                EXTRACT_16BITS(&ldp_com_header->version)));
579 	return 0;
580     }
581 
582     pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
583     if (pdu_len < sizeof(const struct ldp_common_header)-4) {
584         /* length too short */
585         ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
586                (ndo->ndo_vflag < 1) ? "" : "\n\t",
587                pdu_len,
588                (u_int)(sizeof(const struct ldp_common_header)-4)));
589         return 0;
590     }
591 
592     /* print the LSR-ID, label-space & length */
593     ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
594            (ndo->ndo_vflag < 1) ? "" : "\n\t",
595            ipaddr_string(ndo, &ldp_com_header->lsr_id),
596            EXTRACT_16BITS(&ldp_com_header->label_space),
597            pdu_len));
598 
599     /* bail out if non-verbose */
600     if (ndo->ndo_vflag < 1)
601         return 0;
602 
603     /* ok they seem to want to know everything - lets fully decode it */
604     tptr = pptr + sizeof(const struct ldp_common_header);
605     tlen = pdu_len - (sizeof(const struct ldp_common_header)-4);	/* Type & Length fields not included */
606 
607     while(tlen>0) {
608         /* did we capture enough for fully decoding the msg header ? */
609         ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
610 
611         ldp_msg_header = (const struct ldp_msg_header *)tptr;
612         msg_len=EXTRACT_16BITS(ldp_msg_header->length);
613         msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
614 
615         if (msg_len < sizeof(struct ldp_msg_header)-4) {
616             /* length too short */
617             /* FIXME vendor private / experimental check */
618             ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u (too short, < %u)",
619                    tok2str(ldp_msg_values,
620                            "Unknown",
621                            msg_type),
622                    msg_type,
623                    msg_len,
624                    (u_int)(sizeof(struct ldp_msg_header)-4)));
625             return 0;
626         }
627 
628         /* FIXME vendor private / experimental check */
629         ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
630                tok2str(ldp_msg_values,
631                        "Unknown",
632                        msg_type),
633                msg_type,
634                msg_len,
635                EXTRACT_32BITS(&ldp_msg_header->id),
636                LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
637 
638         msg_tptr=tptr+sizeof(struct ldp_msg_header);
639         msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
640 
641         /* did we capture enough for fully decoding the message ? */
642         ND_TCHECK2(*tptr, msg_len);
643         hexdump=FALSE;
644 
645         switch(msg_type) {
646 
647         case LDP_MSG_NOTIF:
648         case LDP_MSG_HELLO:
649         case LDP_MSG_INIT:
650         case LDP_MSG_KEEPALIVE:
651         case LDP_MSG_ADDRESS:
652         case LDP_MSG_LABEL_MAPPING:
653         case LDP_MSG_ADDRESS_WITHDRAW:
654         case LDP_MSG_LABEL_WITHDRAW:
655             while(msg_tlen >= 4) {
656                 processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
657                 if (processed == 0)
658                     break;
659                 msg_tlen-=processed;
660                 msg_tptr+=processed;
661             }
662             break;
663 
664         /*
665          *  FIXME those are the defined messages that lack a decoder
666          *  you are welcome to contribute code ;-)
667          */
668 
669         case LDP_MSG_LABEL_REQUEST:
670         case LDP_MSG_LABEL_RELEASE:
671         case LDP_MSG_LABEL_ABORT_REQUEST:
672 
673         default:
674             if (ndo->ndo_vflag <= 1)
675                 print_unknown_data(ndo, msg_tptr, "\n\t  ", msg_tlen);
676             break;
677         }
678         /* do we want to see an additionally hexdump ? */
679         if (ndo->ndo_vflag > 1 || hexdump==TRUE)
680             print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t  ",
681                                msg_len);
682 
683         tptr += msg_len+4;
684         tlen -= msg_len+4;
685     }
686     return pdu_len+4;
687 trunc:
688     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
689     return 0;
690 }
691 
692 /*
693  * Local Variables:
694  * c-style: whitesmith
695  * c-basic-offset: 8
696  * End:
697  */
698