xref: /freebsd/contrib/tcpdump/print-ldp.c (revision 6ae1554a5d9b318f8ad53ccc39fa5a961403da73)
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 #define NETDISSECT_REWORKED
18 #ifdef HAVE_CONFIG_H
19 #include "config.h"
20 #endif
21 
22 #include <tcpdump-stdinc.h>
23 
24 #include "interface.h"
25 #include "extract.h"
26 #include "addrtoname.h"
27 
28 #include "l2vpn.h"
29 #include "af.h"
30 
31 /*
32  * ldp common header
33  *
34  *  0                   1                   2                   3
35  *  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
36  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
37  * |  Version                      |         PDU Length            |
38  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39  * |                         LDP Identifier                        |
40  * +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41  * |                               |
42  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43  *
44  */
45 
46 struct ldp_common_header {
47     uint8_t version[2];
48     uint8_t pdu_length[2];
49     uint8_t lsr_id[4];
50     uint8_t label_space[2];
51 };
52 
53 #define LDP_VERSION 1
54 
55 /*
56  * ldp message header
57  *
58  *  0                   1                   2                   3
59  *  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
60  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
61  * |U|   Message Type              |      Message Length           |
62  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63  * |                     Message ID                                |
64  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65  * |                                                               |
66  * +                                                               +
67  * |                     Mandatory Parameters                      |
68  * +                                                               +
69  * |                                                               |
70  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71  * |                                                               |
72  * +                                                               +
73  * |                     Optional Parameters                       |
74  * +                                                               +
75  * |                                                               |
76  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77  */
78 
79 struct ldp_msg_header {
80     uint8_t type[2];
81     uint8_t length[2];
82     uint8_t id[4];
83 };
84 
85 #define	LDP_MASK_MSG_TYPE(x)  ((x)&0x7fff)
86 #define	LDP_MASK_U_BIT(x)     ((x)&0x8000)
87 
88 #define	LDP_MSG_NOTIF                0x0001
89 #define	LDP_MSG_HELLO                0x0100
90 #define	LDP_MSG_INIT                 0x0200
91 #define	LDP_MSG_KEEPALIVE            0x0201
92 #define	LDP_MSG_ADDRESS              0x0300
93 #define	LDP_MSG_ADDRESS_WITHDRAW     0x0301
94 #define	LDP_MSG_LABEL_MAPPING        0x0400
95 #define	LDP_MSG_LABEL_REQUEST        0x0401
96 #define	LDP_MSG_LABEL_WITHDRAW       0x0402
97 #define	LDP_MSG_LABEL_RELEASE        0x0403
98 #define	LDP_MSG_LABEL_ABORT_REQUEST  0x0404
99 
100 #define	LDP_VENDOR_PRIVATE_MIN       0x3e00
101 #define	LDP_VENDOR_PRIVATE_MAX       0x3eff
102 #define	LDP_EXPERIMENTAL_MIN         0x3f00
103 #define	LDP_EXPERIMENTAL_MAX         0x3fff
104 
105 static const struct tok ldp_msg_values[] = {
106     { LDP_MSG_NOTIF,	             "Notification" },
107     { LDP_MSG_HELLO,	             "Hello" },
108     { LDP_MSG_INIT,	             "Initialization" },
109     { LDP_MSG_KEEPALIVE,             "Keepalive" },
110     { LDP_MSG_ADDRESS,	             "Address" },
111     { LDP_MSG_ADDRESS_WITHDRAW,	     "Address Withdraw" },
112     { LDP_MSG_LABEL_MAPPING,	     "Label Mapping" },
113     { LDP_MSG_LABEL_REQUEST,	     "Label Request" },
114     { LDP_MSG_LABEL_WITHDRAW,	     "Label Withdraw" },
115     { LDP_MSG_LABEL_RELEASE,	     "Label Release" },
116     { LDP_MSG_LABEL_ABORT_REQUEST,   "Label Abort Request" },
117     { 0, NULL}
118 };
119 
120 #define	LDP_MASK_TLV_TYPE(x)  ((x)&0x3fff)
121 #define	LDP_MASK_F_BIT(x) ((x)&0x4000)
122 
123 #define	LDP_TLV_FEC                  0x0100
124 #define	LDP_TLV_ADDRESS_LIST         0x0101
125 #define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
126 #define	LDP_TLV_HOP_COUNT            0x0103
127 #define	LDP_TLV_PATH_VECTOR          0x0104
128 #define	LDP_TLV_GENERIC_LABEL        0x0200
129 #define	LDP_TLV_ATM_LABEL            0x0201
130 #define	LDP_TLV_FR_LABEL             0x0202
131 #define	LDP_TLV_STATUS               0x0300
132 #define	LDP_TLV_EXTD_STATUS          0x0301
133 #define	LDP_TLV_RETURNED_PDU         0x0302
134 #define	LDP_TLV_RETURNED_MSG         0x0303
135 #define	LDP_TLV_COMMON_HELLO         0x0400
136 #define	LDP_TLV_IPV4_TRANSPORT_ADDR  0x0401
137 #define	LDP_TLV_CONFIG_SEQ_NUMBER    0x0402
138 #define	LDP_TLV_IPV6_TRANSPORT_ADDR  0x0403
139 #define	LDP_TLV_COMMON_SESSION       0x0500
140 #define	LDP_TLV_ATM_SESSION_PARM     0x0501
141 #define	LDP_TLV_FR_SESSION_PARM      0x0502
142 #define LDP_TLV_FT_SESSION	     0x0503
143 #define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
144 #define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
145 
146 static const struct tok ldp_tlv_values[] = {
147     { LDP_TLV_FEC,	             "FEC" },
148     { LDP_TLV_ADDRESS_LIST,          "Address List" },
149     { LDP_TLV_HOP_COUNT,             "Hop Count" },
150     { LDP_TLV_PATH_VECTOR,           "Path Vector" },
151     { LDP_TLV_GENERIC_LABEL,         "Generic Label" },
152     { LDP_TLV_ATM_LABEL,             "ATM Label" },
153     { LDP_TLV_FR_LABEL,              "Frame-Relay Label" },
154     { LDP_TLV_STATUS,                "Status" },
155     { LDP_TLV_EXTD_STATUS,           "Extended Status" },
156     { LDP_TLV_RETURNED_PDU,          "Returned PDU" },
157     { LDP_TLV_RETURNED_MSG,          "Returned Message" },
158     { LDP_TLV_COMMON_HELLO,          "Common Hello Parameters" },
159     { LDP_TLV_IPV4_TRANSPORT_ADDR,   "IPv4 Transport Address" },
160     { LDP_TLV_CONFIG_SEQ_NUMBER,     "Configuration Sequence Number" },
161     { LDP_TLV_IPV6_TRANSPORT_ADDR,   "IPv6 Transport Address" },
162     { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
163     { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
164     { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
165     { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
166     { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
167     { LDP_TLV_MTU,                   "MTU" },
168     { 0, NULL}
169 };
170 
171 #define LDP_FEC_WILDCARD	0x01
172 #define LDP_FEC_PREFIX		0x02
173 #define LDP_FEC_HOSTADDRESS	0x03
174 /* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
175 #define LDP_FEC_MARTINI_VC	0x80
176 
177 static const struct tok ldp_fec_values[] = {
178     { LDP_FEC_WILDCARD,		"Wildcard" },
179     { LDP_FEC_PREFIX,		"Prefix" },
180     { LDP_FEC_HOSTADDRESS,	"Host address" },
181     { LDP_FEC_MARTINI_VC,	"Martini VC" },
182     { 0, NULL}
183 };
184 
185 #define LDP_FEC_MARTINI_IFPARM_MTU  0x01
186 #define LDP_FEC_MARTINI_IFPARM_DESC 0x03
187 #define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
188 
189 static const struct tok ldp_fec_martini_ifparm_values[] = {
190     { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
191     { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
192     { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
193     { 0, NULL}
194 };
195 
196 /* draft-ietf-pwe3-vccv-04.txt */
197 static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
198     { 0x01, "PWE3 control word" },
199     { 0x02, "MPLS Router Alert Label" },
200     { 0x04, "MPLS inner label TTL = 1" },
201     { 0, NULL}
202 };
203 
204 /* draft-ietf-pwe3-vccv-04.txt */
205 static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
206     { 0x01, "ICMP Ping" },
207     { 0x02, "LSP Ping" },
208     { 0x04, "BFD" },
209     { 0, NULL}
210 };
211 
212 static int ldp_pdu_print(netdissect_options *, register const u_char *);
213 
214 /*
215  * ldp tlv header
216  *
217  *  0                   1                   2                   3
218  *  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
219  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
220  * |U|F|        Type               |            Length             |
221  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
222  * |                                                               |
223  * |                             Value                             |
224  * ~                                                               ~
225  * |                                                               |
226  * |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
227  * |                               |
228  * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
229  */
230 
231 #define TLV_TCHECK(minlen) \
232     ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
233 
234 static int
235 ldp_tlv_print(netdissect_options *ndo,
236               register const u_char *tptr,
237               u_short msg_tlen)
238 {
239     struct ldp_tlv_header {
240         uint8_t type[2];
241         uint8_t length[2];
242     };
243 
244     const struct ldp_tlv_header *ldp_tlv_header;
245     u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
246     u_char fec_type;
247     u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
248     char buf[100];
249     int i;
250 
251     ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
252     ND_TCHECK(*ldp_tlv_header);
253     tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
254     if (tlv_len + 4 > msg_tlen) {
255         ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
256         return 0;
257     }
258     tlv_tlen=tlv_len;
259     tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
260 
261     /* FIXME vendor private / experimental check */
262     ND_PRINT((ndo, "\n\t    %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
263            tok2str(ldp_tlv_values,
264                    "Unknown",
265                    tlv_type),
266            tlv_type,
267            tlv_len,
268            LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
269            LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
270 
271     tptr+=sizeof(struct ldp_tlv_header);
272 
273     switch(tlv_type) {
274 
275     case LDP_TLV_COMMON_HELLO:
276         TLV_TCHECK(4);
277         ND_PRINT((ndo, "\n\t      Hold Time: %us, Flags: [%s Hello%s]",
278                EXTRACT_16BITS(tptr),
279                (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
280                (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
281         break;
282 
283     case LDP_TLV_IPV4_TRANSPORT_ADDR:
284         TLV_TCHECK(4);
285         ND_PRINT((ndo, "\n\t      IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
286         break;
287 #ifdef INET6
288     case LDP_TLV_IPV6_TRANSPORT_ADDR:
289         TLV_TCHECK(16);
290         ND_PRINT((ndo, "\n\t      IPv6 Transport Address: %s", ip6addr_string(ndo, tptr)));
291         break;
292 #endif
293     case LDP_TLV_CONFIG_SEQ_NUMBER:
294         TLV_TCHECK(4);
295         ND_PRINT((ndo, "\n\t      Sequence Number: %u", EXTRACT_32BITS(tptr)));
296         break;
297 
298     case LDP_TLV_ADDRESS_LIST:
299         TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
300 	af = EXTRACT_16BITS(tptr);
301 	tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
302         tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
303 	ND_PRINT((ndo, "\n\t      Address Family: %s, addresses",
304                tok2str(af_values, "Unknown (%u)", af)));
305         switch (af) {
306         case AFNUM_INET:
307 	    while(tlv_tlen >= sizeof(struct in_addr)) {
308 		ND_TCHECK2(*tptr, sizeof(struct in_addr));
309 		ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
310 		tlv_tlen-=sizeof(struct in_addr);
311 		tptr+=sizeof(struct in_addr);
312 	    }
313             break;
314 #ifdef INET6
315         case AFNUM_INET6:
316 	    while(tlv_tlen >= sizeof(struct in6_addr)) {
317 		ND_TCHECK2(*tptr, sizeof(struct in6_addr));
318 		ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
319 		tlv_tlen-=sizeof(struct in6_addr);
320 		tptr+=sizeof(struct in6_addr);
321 	    }
322             break;
323 #endif
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 #ifdef INET6
369 	    else if (af == AFNUM_INET6) {
370 		i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
371 		if (i == -2)
372 		    goto trunc;
373 		if (i == -3)
374 		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
375 		else if (i == -1)
376 		    ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
377 		else
378 		    ND_PRINT((ndo, ": IPv6 prefix %s", buf));
379 	    }
380 #endif
381 	    else
382 		ND_PRINT((ndo, ": Address family %u prefix", af));
383 	    break;
384 	case LDP_FEC_HOSTADDRESS:
385 	    break;
386 	case LDP_FEC_MARTINI_VC:
387             /*
388 	     * According to RFC 4908, the VC info Length field can be zero,
389 	     * in which case not only are there no interface parameters,
390 	     * there's no VC ID.
391 	     */
392             TLV_TCHECK(7);
393             vc_info_len = *(tptr+2);
394 
395             if (vc_info_len == 0) {
396                 ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
397                        tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
398                        EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
399                        EXTRACT_32BITS(tptr+3),
400                        vc_info_len));
401                 break;
402             }
403 
404             /* Make sure we have the VC ID as well */
405             TLV_TCHECK(11);
406 	    ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
407 		   tok2str(l2vpn_encaps_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
408 		   EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
409                    EXTRACT_32BITS(tptr+3),
410 		   EXTRACT_32BITS(tptr+7),
411                    vc_info_len));
412             if (vc_info_len < 4) {
413                 /* minimum 4, for the VC ID */
414                 ND_PRINT((ndo, " (invalid, < 4"));
415                 return(tlv_len+4); /* Type & Length fields not included */
416 	    }
417             vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
418 
419             /* Skip past the fixed information and the VC ID */
420             tptr+=11;
421             tlv_tlen-=11;
422             TLV_TCHECK(vc_info_len);
423 
424             while (vc_info_len > 2) {
425                 vc_info_tlv_type = *tptr;
426                 vc_info_tlv_len = *(tptr+1);
427                 if (vc_info_tlv_len < 2)
428                     break;
429                 if (vc_info_len < vc_info_tlv_len)
430                     break;
431 
432                 ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
433                        tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
434                        vc_info_tlv_type,
435                        vc_info_tlv_len));
436 
437                 switch(vc_info_tlv_type) {
438                 case LDP_FEC_MARTINI_IFPARM_MTU:
439                     ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
440                     break;
441 
442                 case LDP_FEC_MARTINI_IFPARM_DESC:
443                     ND_PRINT((ndo, ": "));
444                     for (idx = 2; idx < vc_info_tlv_len; idx++)
445                         safeputchar(ndo, *(tptr + idx));
446                     break;
447 
448                 case LDP_FEC_MARTINI_IFPARM_VCCV:
449                     ND_PRINT((ndo, "\n\t\t  Control Channels (0x%02x) = [%s]",
450                            *(tptr+2),
451                            bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
452                     ND_PRINT((ndo, "\n\t\t  CV Types (0x%02x) = [%s]",
453                            *(tptr+3),
454                            bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
455                     break;
456 
457                 default:
458                     print_unknown_data(ndo, tptr+2, "\n\t\t  ", vc_info_tlv_len-2);
459                     break;
460                 }
461 
462                 vc_info_len -= vc_info_tlv_len;
463                 tptr += vc_info_tlv_len;
464             }
465 	    break;
466 	}
467 
468 	break;
469 
470     case LDP_TLV_GENERIC_LABEL:
471 	TLV_TCHECK(4);
472 	ND_PRINT((ndo, "\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
473 	break;
474 
475     case LDP_TLV_STATUS:
476 	TLV_TCHECK(8);
477 	ui = EXTRACT_32BITS(tptr);
478 	tptr+=4;
479 	ND_PRINT((ndo, "\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
480 	       ui&0x3fffffff,
481 	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
482 	       ui&0x40000000 ? "do" : "don't"));
483 	ui = EXTRACT_32BITS(tptr);
484 	tptr+=4;
485 	if (ui)
486 	    ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
487 	break;
488 
489     case LDP_TLV_FT_SESSION:
490 	TLV_TCHECK(8);
491 	ft_flags = EXTRACT_16BITS(tptr);
492 	ND_PRINT((ndo, "\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
493 	       ft_flags&0x8000 ? "" : "No ",
494 	       ft_flags&0x8 ? "" : "Don't ",
495 	       ft_flags&0x4 ? "" : "No ",
496 	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
497 	       ft_flags&0x1 ? "" : "Don't "));
498 	tptr+=4;
499 	ui = EXTRACT_32BITS(tptr);
500 	if (ui)
501 	    ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
502 	tptr+=4;
503 	ui = EXTRACT_32BITS(tptr);
504 	if (ui)
505 	    ND_PRINT((ndo, ", Recovery Time: %ums", ui));
506 	break;
507 
508     case LDP_TLV_MTU:
509 	TLV_TCHECK(2);
510 	ND_PRINT((ndo, "\n\t      MTU: %u", EXTRACT_16BITS(tptr)));
511 	break;
512 
513 
514     /*
515      *  FIXME those are the defined TLVs that lack a decoder
516      *  you are welcome to contribute code ;-)
517      */
518 
519     case LDP_TLV_HOP_COUNT:
520     case LDP_TLV_PATH_VECTOR:
521     case LDP_TLV_ATM_LABEL:
522     case LDP_TLV_FR_LABEL:
523     case LDP_TLV_EXTD_STATUS:
524     case LDP_TLV_RETURNED_PDU:
525     case LDP_TLV_RETURNED_MSG:
526     case LDP_TLV_ATM_SESSION_PARM:
527     case LDP_TLV_FR_SESSION_PARM:
528     case LDP_TLV_LABEL_REQUEST_MSG_ID:
529 
530     default:
531         if (ndo->ndo_vflag <= 1)
532             print_unknown_data(ndo, tptr, "\n\t      ", tlv_tlen);
533         break;
534     }
535     return(tlv_len+4); /* Type & Length fields not included */
536 
537 trunc:
538     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
539     return 0;
540 
541 badtlv:
542     ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
543     return(tlv_len+4); /* Type & Length fields not included */
544 }
545 
546 void
547 ldp_print(netdissect_options *ndo,
548           register const u_char *pptr, register u_int len)
549 {
550     int processed;
551     while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
552         processed = ldp_pdu_print(ndo, pptr);
553         if (processed == 0)
554             return;
555         len -= processed;
556         pptr += processed;
557     }
558 }
559 
560 static int
561 ldp_pdu_print(netdissect_options *ndo,
562               register const u_char *pptr)
563 {
564     const struct ldp_common_header *ldp_com_header;
565     const struct ldp_msg_header *ldp_msg_header;
566     const u_char *tptr,*msg_tptr;
567     u_short tlen;
568     u_short pdu_len,msg_len,msg_type,msg_tlen;
569     int hexdump,processed;
570 
571     ldp_com_header = (const struct ldp_common_header *)pptr;
572     ND_TCHECK(*ldp_com_header);
573 
574     /*
575      * Sanity checking of the header.
576      */
577     if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
578 	ND_PRINT((ndo, "%sLDP version %u packet not supported",
579                (ndo->ndo_vflag < 1) ? "" : "\n\t",
580                EXTRACT_16BITS(&ldp_com_header->version)));
581 	return 0;
582     }
583 
584     pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
585     if (pdu_len < sizeof(const struct ldp_common_header)-4) {
586         /* length too short */
587         ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
588                (ndo->ndo_vflag < 1) ? "" : "\n\t",
589                pdu_len,
590                (u_int)(sizeof(const struct ldp_common_header)-4)));
591         return 0;
592     }
593 
594     /* print the LSR-ID, label-space & length */
595     ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
596            (ndo->ndo_vflag < 1) ? "" : "\n\t",
597            ipaddr_string(ndo, &ldp_com_header->lsr_id),
598            EXTRACT_16BITS(&ldp_com_header->label_space),
599            pdu_len));
600 
601     /* bail out if non-verbose */
602     if (ndo->ndo_vflag < 1)
603         return 0;
604 
605     /* ok they seem to want to know everything - lets fully decode it */
606     tptr = pptr + sizeof(const struct ldp_common_header);
607     tlen = pdu_len - (sizeof(const struct ldp_common_header)-4);	/* Type & Length fields not included */
608 
609     while(tlen>0) {
610         /* did we capture enough for fully decoding the msg header ? */
611         ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
612 
613         ldp_msg_header = (const struct ldp_msg_header *)tptr;
614         msg_len=EXTRACT_16BITS(ldp_msg_header->length);
615         msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
616 
617         if (msg_len < sizeof(struct ldp_msg_header)-4) {
618             /* length too short */
619             /* FIXME vendor private / experimental check */
620             ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u (too short, < %u)",
621                    tok2str(ldp_msg_values,
622                            "Unknown",
623                            msg_type),
624                    msg_type,
625                    msg_len,
626                    (u_int)(sizeof(struct ldp_msg_header)-4)));
627             return 0;
628         }
629 
630         /* FIXME vendor private / experimental check */
631         ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
632                tok2str(ldp_msg_values,
633                        "Unknown",
634                        msg_type),
635                msg_type,
636                msg_len,
637                EXTRACT_32BITS(&ldp_msg_header->id),
638                LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
639 
640         msg_tptr=tptr+sizeof(struct ldp_msg_header);
641         msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
642 
643         /* did we capture enough for fully decoding the message ? */
644         ND_TCHECK2(*tptr, msg_len);
645         hexdump=FALSE;
646 
647         switch(msg_type) {
648 
649         case LDP_MSG_NOTIF:
650         case LDP_MSG_HELLO:
651         case LDP_MSG_INIT:
652         case LDP_MSG_KEEPALIVE:
653         case LDP_MSG_ADDRESS:
654         case LDP_MSG_LABEL_MAPPING:
655         case LDP_MSG_ADDRESS_WITHDRAW:
656         case LDP_MSG_LABEL_WITHDRAW:
657             while(msg_tlen >= 4) {
658                 processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
659                 if (processed == 0)
660                     break;
661                 msg_tlen-=processed;
662                 msg_tptr+=processed;
663             }
664             break;
665 
666         /*
667          *  FIXME those are the defined messages that lack a decoder
668          *  you are welcome to contribute code ;-)
669          */
670 
671         case LDP_MSG_LABEL_REQUEST:
672         case LDP_MSG_LABEL_RELEASE:
673         case LDP_MSG_LABEL_ABORT_REQUEST:
674 
675         default:
676             if (ndo->ndo_vflag <= 1)
677                 print_unknown_data(ndo, msg_tptr, "\n\t  ", msg_tlen);
678             break;
679         }
680         /* do we want to see an additionally hexdump ? */
681         if (ndo->ndo_vflag > 1 || hexdump==TRUE)
682             print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t  ",
683                                msg_len);
684 
685         tptr += msg_len+4;
686         tlen -= msg_len+4;
687     }
688     return pdu_len+4;
689 trunc:
690     ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
691     return 0;
692 }
693 
694 /*
695  * Local Variables:
696  * c-style: whitesmith
697  * c-basic-offset: 8
698  * End:
699  */
700