print-ldp.c revision 1.8
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 1.8 2017/02/05 04:05:05 spz Exp $");
20#endif
21
22/* \summary: Label Distribution Protocol (LDP) printer */
23
24#ifdef HAVE_CONFIG_H
25#include "config.h"
26#endif
27
28#include <netdissect-stdinc.h>
29
30#include "netdissect.h"
31#include "extract.h"
32#include "addrtoname.h"
33
34#include "l2vpn.h"
35#include "af.h"
36
37/*
38 * ldp common header
39 *
40 *  0                   1                   2                   3
41 *  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
42 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43 * |  Version                      |         PDU Length            |
44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 * |                         LDP Identifier                        |
46 * +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
47 * |                               |
48 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
49 *
50 */
51
52struct ldp_common_header {
53    uint8_t version[2];
54    uint8_t pdu_length[2];
55    uint8_t lsr_id[4];
56    uint8_t label_space[2];
57};
58
59#define LDP_VERSION 1
60
61/*
62 * ldp message header
63 *
64 *  0                   1                   2                   3
65 *  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
66 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67 * |U|   Message Type              |      Message Length           |
68 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
69 * |                     Message ID                                |
70 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
71 * |                                                               |
72 * +                                                               +
73 * |                     Mandatory Parameters                      |
74 * +                                                               +
75 * |                                                               |
76 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
77 * |                                                               |
78 * +                                                               +
79 * |                     Optional Parameters                       |
80 * +                                                               +
81 * |                                                               |
82 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
83 */
84
85struct ldp_msg_header {
86    uint8_t type[2];
87    uint8_t length[2];
88    uint8_t id[4];
89};
90
91#define	LDP_MASK_MSG_TYPE(x)  ((x)&0x7fff)
92#define	LDP_MASK_U_BIT(x)     ((x)&0x8000)
93
94#define	LDP_MSG_NOTIF                0x0001
95#define	LDP_MSG_HELLO                0x0100
96#define	LDP_MSG_INIT                 0x0200
97#define	LDP_MSG_KEEPALIVE            0x0201
98#define	LDP_MSG_ADDRESS              0x0300
99#define	LDP_MSG_ADDRESS_WITHDRAW     0x0301
100#define	LDP_MSG_LABEL_MAPPING        0x0400
101#define	LDP_MSG_LABEL_REQUEST        0x0401
102#define	LDP_MSG_LABEL_WITHDRAW       0x0402
103#define	LDP_MSG_LABEL_RELEASE        0x0403
104#define	LDP_MSG_LABEL_ABORT_REQUEST  0x0404
105
106#define	LDP_VENDOR_PRIVATE_MIN       0x3e00
107#define	LDP_VENDOR_PRIVATE_MAX       0x3eff
108#define	LDP_EXPERIMENTAL_MIN         0x3f00
109#define	LDP_EXPERIMENTAL_MAX         0x3fff
110
111static const struct tok ldp_msg_values[] = {
112    { LDP_MSG_NOTIF,	             "Notification" },
113    { LDP_MSG_HELLO,	             "Hello" },
114    { LDP_MSG_INIT,	             "Initialization" },
115    { LDP_MSG_KEEPALIVE,             "Keepalive" },
116    { LDP_MSG_ADDRESS,	             "Address" },
117    { LDP_MSG_ADDRESS_WITHDRAW,	     "Address Withdraw" },
118    { LDP_MSG_LABEL_MAPPING,	     "Label Mapping" },
119    { LDP_MSG_LABEL_REQUEST,	     "Label Request" },
120    { LDP_MSG_LABEL_WITHDRAW,	     "Label Withdraw" },
121    { LDP_MSG_LABEL_RELEASE,	     "Label Release" },
122    { LDP_MSG_LABEL_ABORT_REQUEST,   "Label Abort Request" },
123    { 0, NULL}
124};
125
126#define	LDP_MASK_TLV_TYPE(x)  ((x)&0x3fff)
127#define	LDP_MASK_F_BIT(x) ((x)&0x4000)
128
129#define	LDP_TLV_FEC                  0x0100
130#define	LDP_TLV_ADDRESS_LIST         0x0101
131#define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
132#define	LDP_TLV_HOP_COUNT            0x0103
133#define	LDP_TLV_PATH_VECTOR          0x0104
134#define	LDP_TLV_GENERIC_LABEL        0x0200
135#define	LDP_TLV_ATM_LABEL            0x0201
136#define	LDP_TLV_FR_LABEL             0x0202
137#define	LDP_TLV_STATUS               0x0300
138#define	LDP_TLV_EXTD_STATUS          0x0301
139#define	LDP_TLV_RETURNED_PDU         0x0302
140#define	LDP_TLV_RETURNED_MSG         0x0303
141#define	LDP_TLV_COMMON_HELLO         0x0400
142#define	LDP_TLV_IPV4_TRANSPORT_ADDR  0x0401
143#define	LDP_TLV_CONFIG_SEQ_NUMBER    0x0402
144#define	LDP_TLV_IPV6_TRANSPORT_ADDR  0x0403
145#define	LDP_TLV_COMMON_SESSION       0x0500
146#define	LDP_TLV_ATM_SESSION_PARM     0x0501
147#define	LDP_TLV_FR_SESSION_PARM      0x0502
148#define LDP_TLV_FT_SESSION	     0x0503
149#define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
150#define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
151
152static const struct tok ldp_tlv_values[] = {
153    { LDP_TLV_FEC,	             "FEC" },
154    { LDP_TLV_ADDRESS_LIST,          "Address List" },
155    { LDP_TLV_HOP_COUNT,             "Hop Count" },
156    { LDP_TLV_PATH_VECTOR,           "Path Vector" },
157    { LDP_TLV_GENERIC_LABEL,         "Generic Label" },
158    { LDP_TLV_ATM_LABEL,             "ATM Label" },
159    { LDP_TLV_FR_LABEL,              "Frame-Relay Label" },
160    { LDP_TLV_STATUS,                "Status" },
161    { LDP_TLV_EXTD_STATUS,           "Extended Status" },
162    { LDP_TLV_RETURNED_PDU,          "Returned PDU" },
163    { LDP_TLV_RETURNED_MSG,          "Returned Message" },
164    { LDP_TLV_COMMON_HELLO,          "Common Hello Parameters" },
165    { LDP_TLV_IPV4_TRANSPORT_ADDR,   "IPv4 Transport Address" },
166    { LDP_TLV_CONFIG_SEQ_NUMBER,     "Configuration Sequence Number" },
167    { LDP_TLV_IPV6_TRANSPORT_ADDR,   "IPv6 Transport Address" },
168    { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
169    { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
170    { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
171    { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
172    { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
173    { LDP_TLV_MTU,                   "MTU" },
174    { 0, NULL}
175};
176
177#define LDP_FEC_WILDCARD	0x01
178#define LDP_FEC_PREFIX		0x02
179#define LDP_FEC_HOSTADDRESS	0x03
180/* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
181#define LDP_FEC_MARTINI_VC	0x80
182
183static const struct tok ldp_fec_values[] = {
184    { LDP_FEC_WILDCARD,		"Wildcard" },
185    { LDP_FEC_PREFIX,		"Prefix" },
186    { LDP_FEC_HOSTADDRESS,	"Host address" },
187    { LDP_FEC_MARTINI_VC,	"Martini VC" },
188    { 0, NULL}
189};
190
191#define LDP_FEC_MARTINI_IFPARM_MTU  0x01
192#define LDP_FEC_MARTINI_IFPARM_DESC 0x03
193#define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
194
195static const struct tok ldp_fec_martini_ifparm_values[] = {
196    { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
197    { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
198    { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
199    { 0, NULL}
200};
201
202/* draft-ietf-pwe3-vccv-04.txt */
203static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
204    { 0x01, "PWE3 control word" },
205    { 0x02, "MPLS Router Alert Label" },
206    { 0x04, "MPLS inner label TTL = 1" },
207    { 0, NULL}
208};
209
210/* draft-ietf-pwe3-vccv-04.txt */
211static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
212    { 0x01, "ICMP Ping" },
213    { 0x02, "LSP Ping" },
214    { 0x04, "BFD" },
215    { 0, NULL}
216};
217
218static int ldp_pdu_print(netdissect_options *, register const u_char *);
219
220/*
221 * ldp tlv header
222 *
223 *  0                   1                   2                   3
224 *  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
225 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
226 * |U|F|        Type               |            Length             |
227 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
228 * |                                                               |
229 * |                             Value                             |
230 * ~                                                               ~
231 * |                                                               |
232 * |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
233 * |                               |
234 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
235 */
236
237#define TLV_TCHECK(minlen) \
238    ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
239
240static int
241ldp_tlv_print(netdissect_options *ndo,
242              register const u_char *tptr,
243              u_short msg_tlen)
244{
245    struct ldp_tlv_header {
246        uint8_t type[2];
247        uint8_t length[2];
248    };
249
250    const struct ldp_tlv_header *ldp_tlv_header;
251    u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
252    u_char fec_type;
253    u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
254    char buf[100];
255    int i;
256
257    ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
258    ND_TCHECK(*ldp_tlv_header);
259    tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
260    if (tlv_len + 4 > msg_tlen) {
261        ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
262        return 0;
263    }
264    tlv_tlen=tlv_len;
265    tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
266
267    /* FIXME vendor private / experimental check */
268    ND_PRINT((ndo, "\n\t    %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
269           tok2str(ldp_tlv_values,
270                   "Unknown",
271                   tlv_type),
272           tlv_type,
273           tlv_len,
274           LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
275           LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
276
277    tptr+=sizeof(struct ldp_tlv_header);
278
279    switch(tlv_type) {
280
281    case LDP_TLV_COMMON_HELLO:
282        TLV_TCHECK(4);
283        ND_PRINT((ndo, "\n\t      Hold Time: %us, Flags: [%s Hello%s]",
284               EXTRACT_16BITS(tptr),
285               (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
286               (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
287        break;
288
289    case LDP_TLV_IPV4_TRANSPORT_ADDR:
290        TLV_TCHECK(4);
291        ND_PRINT((ndo, "\n\t      IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
292        break;
293    case LDP_TLV_IPV6_TRANSPORT_ADDR:
294        TLV_TCHECK(16);
295        ND_PRINT((ndo, "\n\t      IPv6 Transport Address: %s", ip6addr_string(ndo, tptr)));
296        break;
297    case LDP_TLV_CONFIG_SEQ_NUMBER:
298        TLV_TCHECK(4);
299        ND_PRINT((ndo, "\n\t      Sequence Number: %u", EXTRACT_32BITS(tptr)));
300        break;
301
302    case LDP_TLV_ADDRESS_LIST:
303        TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
304	af = EXTRACT_16BITS(tptr);
305	tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
306        tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
307	ND_PRINT((ndo, "\n\t      Address Family: %s, addresses",
308               tok2str(af_values, "Unknown (%u)", af)));
309        switch (af) {
310        case AFNUM_INET:
311	    while(tlv_tlen >= sizeof(struct in_addr)) {
312		ND_TCHECK2(*tptr, sizeof(struct in_addr));
313		ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
314		tlv_tlen-=sizeof(struct in_addr);
315		tptr+=sizeof(struct in_addr);
316	    }
317            break;
318        case AFNUM_INET6:
319	    while(tlv_tlen >= sizeof(struct in6_addr)) {
320		ND_TCHECK2(*tptr, sizeof(struct in6_addr));
321		ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
322		tlv_tlen-=sizeof(struct in6_addr);
323		tptr+=sizeof(struct in6_addr);
324	    }
325            break;
326        default:
327            /* unknown AF */
328            break;
329        }
330	break;
331
332    case LDP_TLV_COMMON_SESSION:
333	TLV_TCHECK(8);
334	ND_PRINT((ndo, "\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
335	       EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
336	       (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
337	       (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
338	       ));
339	break;
340
341    case LDP_TLV_FEC:
342        TLV_TCHECK(1);
343        fec_type = *tptr;
344	ND_PRINT((ndo, "\n\t      %s FEC (0x%02x)",
345	       tok2str(ldp_fec_values, "Unknown", fec_type),
346	       fec_type));
347
348	tptr+=1;
349	tlv_tlen-=1;
350	switch(fec_type) {
351
352	case LDP_FEC_WILDCARD:
353	    break;
354	case LDP_FEC_PREFIX:
355	    TLV_TCHECK(2);
356	    af = EXTRACT_16BITS(tptr);
357	    tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
358	    tlv_tlen-=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
359	    if (af == AFNUM_INET) {
360		i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
361		if (i == -2)
362		    goto trunc;
363		if (i == -3)
364		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
365		else if (i == -1)
366		    ND_PRINT((ndo, ": IPv4 prefix (invalid length)"));
367		else
368		    ND_PRINT((ndo, ": IPv4 prefix %s", buf));
369	    }
370	    else if (af == AFNUM_INET6) {
371		i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
372		if (i == -2)
373		    goto trunc;
374		if (i == -3)
375		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
376		else if (i == -1)
377		    ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
378		else
379		    ND_PRINT((ndo, ": IPv6 prefix %s", buf));
380	    }
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             * We assume the type was supposed to be one of the MPLS
389             * Pseudowire Types.
390             */
391            TLV_TCHECK(7);
392            vc_info_len = *(tptr+2);
393
394            /*
395	     * According to RFC 4908, the VC info Length field can be zero,
396	     * in which case not only are there no interface parameters,
397	     * there's no VC ID.
398	     */
399            if (vc_info_len == 0) {
400                ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
401                       tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
402                       EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
403                       EXTRACT_32BITS(tptr+3),
404                       vc_info_len));
405                break;
406            }
407
408            /* Make sure we have the VC ID as well */
409            TLV_TCHECK(11);
410	    ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
411		   tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
412		   EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
413                   EXTRACT_32BITS(tptr+3),
414		   EXTRACT_32BITS(tptr+7),
415                   vc_info_len));
416            if (vc_info_len < 4) {
417                /* minimum 4, for the VC ID */
418                ND_PRINT((ndo, " (invalid, < 4"));
419                return(tlv_len+4); /* Type & Length fields not included */
420	    }
421            vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
422
423            /* Skip past the fixed information and the VC ID */
424            tptr+=11;
425            tlv_tlen-=11;
426            TLV_TCHECK(vc_info_len);
427
428            while (vc_info_len > 2) {
429                vc_info_tlv_type = *tptr;
430                vc_info_tlv_len = *(tptr+1);
431                if (vc_info_tlv_len < 2)
432                    break;
433                if (vc_info_len < vc_info_tlv_len)
434                    break;
435
436                ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
437                       tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
438                       vc_info_tlv_type,
439                       vc_info_tlv_len));
440
441                switch(vc_info_tlv_type) {
442                case LDP_FEC_MARTINI_IFPARM_MTU:
443                    ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
444                    break;
445
446                case LDP_FEC_MARTINI_IFPARM_DESC:
447                    ND_PRINT((ndo, ": "));
448                    for (idx = 2; idx < vc_info_tlv_len; idx++)
449                        safeputchar(ndo, *(tptr + idx));
450                    break;
451
452                case LDP_FEC_MARTINI_IFPARM_VCCV:
453                    ND_PRINT((ndo, "\n\t\t  Control Channels (0x%02x) = [%s]",
454                           *(tptr+2),
455                           bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
456                    ND_PRINT((ndo, "\n\t\t  CV Types (0x%02x) = [%s]",
457                           *(tptr+3),
458                           bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
459                    break;
460
461                default:
462                    print_unknown_data(ndo, tptr+2, "\n\t\t  ", vc_info_tlv_len-2);
463                    break;
464                }
465
466                vc_info_len -= vc_info_tlv_len;
467                tptr += vc_info_tlv_len;
468            }
469	    break;
470	}
471
472	break;
473
474    case LDP_TLV_GENERIC_LABEL:
475	TLV_TCHECK(4);
476	ND_PRINT((ndo, "\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
477	break;
478
479    case LDP_TLV_STATUS:
480	TLV_TCHECK(8);
481	ui = EXTRACT_32BITS(tptr);
482	tptr+=4;
483	ND_PRINT((ndo, "\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
484	       ui&0x3fffffff,
485	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
486	       ui&0x40000000 ? "do" : "don't"));
487	ui = EXTRACT_32BITS(tptr);
488	tptr+=4;
489	if (ui)
490	    ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
491	break;
492
493    case LDP_TLV_FT_SESSION:
494	TLV_TCHECK(8);
495	ft_flags = EXTRACT_16BITS(tptr);
496	ND_PRINT((ndo, "\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
497	       ft_flags&0x8000 ? "" : "No ",
498	       ft_flags&0x8 ? "" : "Don't ",
499	       ft_flags&0x4 ? "" : "No ",
500	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
501	       ft_flags&0x1 ? "" : "Don't "));
502	tptr+=4;
503	ui = EXTRACT_32BITS(tptr);
504	if (ui)
505	    ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
506	tptr+=4;
507	ui = EXTRACT_32BITS(tptr);
508	if (ui)
509	    ND_PRINT((ndo, ", Recovery Time: %ums", ui));
510	break;
511
512    case LDP_TLV_MTU:
513	TLV_TCHECK(2);
514	ND_PRINT((ndo, "\n\t      MTU: %u", EXTRACT_16BITS(tptr)));
515	break;
516
517
518    /*
519     *  FIXME those are the defined TLVs that lack a decoder
520     *  you are welcome to contribute code ;-)
521     */
522
523    case LDP_TLV_HOP_COUNT:
524    case LDP_TLV_PATH_VECTOR:
525    case LDP_TLV_ATM_LABEL:
526    case LDP_TLV_FR_LABEL:
527    case LDP_TLV_EXTD_STATUS:
528    case LDP_TLV_RETURNED_PDU:
529    case LDP_TLV_RETURNED_MSG:
530    case LDP_TLV_ATM_SESSION_PARM:
531    case LDP_TLV_FR_SESSION_PARM:
532    case LDP_TLV_LABEL_REQUEST_MSG_ID:
533
534    default:
535        if (ndo->ndo_vflag <= 1)
536            print_unknown_data(ndo, tptr, "\n\t      ", tlv_tlen);
537        break;
538    }
539    return(tlv_len+4); /* Type & Length fields not included */
540
541trunc:
542    ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
543    return 0;
544
545badtlv:
546    ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
547    return(tlv_len+4); /* Type & Length fields not included */
548}
549
550void
551ldp_print(netdissect_options *ndo,
552          register const u_char *pptr, register u_int len)
553{
554    int processed;
555    while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
556        processed = ldp_pdu_print(ndo, pptr);
557        if (processed == 0)
558            return;
559        len -= processed;
560        pptr += processed;
561    }
562}
563
564static int
565ldp_pdu_print(netdissect_options *ndo,
566              register const u_char *pptr)
567{
568    const struct ldp_common_header *ldp_com_header;
569    const struct ldp_msg_header *ldp_msg_header;
570    const u_char *tptr,*msg_tptr;
571    u_short tlen;
572    u_short pdu_len,msg_len,msg_type,msg_tlen;
573    int hexdump,processed;
574
575    ldp_com_header = (const struct ldp_common_header *)pptr;
576    ND_TCHECK(*ldp_com_header);
577
578    /*
579     * Sanity checking of the header.
580     */
581    if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
582	ND_PRINT((ndo, "%sLDP version %u packet not supported",
583               (ndo->ndo_vflag < 1) ? "" : "\n\t",
584               EXTRACT_16BITS(&ldp_com_header->version)));
585	return 0;
586    }
587
588    pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
589    if (pdu_len < sizeof(const struct ldp_common_header)-4) {
590        /* length too short */
591        ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
592               (ndo->ndo_vflag < 1) ? "" : "\n\t",
593               pdu_len,
594               (u_int)(sizeof(const struct ldp_common_header)-4)));
595        return 0;
596    }
597
598    /* print the LSR-ID, label-space & length */
599    ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
600           (ndo->ndo_vflag < 1) ? "" : "\n\t",
601           ipaddr_string(ndo, &ldp_com_header->lsr_id),
602           EXTRACT_16BITS(&ldp_com_header->label_space),
603           pdu_len));
604
605    /* bail out if non-verbose */
606    if (ndo->ndo_vflag < 1)
607        return 0;
608
609    /* ok they seem to want to know everything - lets fully decode it */
610    tptr = pptr + sizeof(const struct ldp_common_header);
611    tlen = pdu_len - (sizeof(const struct ldp_common_header)-4);	/* Type & Length fields not included */
612
613    while(tlen>0) {
614        /* did we capture enough for fully decoding the msg header ? */
615        ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
616
617        ldp_msg_header = (const struct ldp_msg_header *)tptr;
618        msg_len=EXTRACT_16BITS(ldp_msg_header->length);
619        msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
620
621        if (msg_len < sizeof(struct ldp_msg_header)-4) {
622            /* length too short */
623            /* FIXME vendor private / experimental check */
624            ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u (too short, < %u)",
625                   tok2str(ldp_msg_values,
626                           "Unknown",
627                           msg_type),
628                   msg_type,
629                   msg_len,
630                   (u_int)(sizeof(struct ldp_msg_header)-4)));
631            return 0;
632        }
633
634        /* FIXME vendor private / experimental check */
635        ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
636               tok2str(ldp_msg_values,
637                       "Unknown",
638                       msg_type),
639               msg_type,
640               msg_len,
641               EXTRACT_32BITS(&ldp_msg_header->id),
642               LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
643
644        msg_tptr=tptr+sizeof(struct ldp_msg_header);
645        msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
646
647        /* did we capture enough for fully decoding the message ? */
648        ND_TCHECK2(*tptr, msg_len);
649        hexdump=FALSE;
650
651        switch(msg_type) {
652
653        case LDP_MSG_NOTIF:
654        case LDP_MSG_HELLO:
655        case LDP_MSG_INIT:
656        case LDP_MSG_KEEPALIVE:
657        case LDP_MSG_ADDRESS:
658        case LDP_MSG_LABEL_MAPPING:
659        case LDP_MSG_ADDRESS_WITHDRAW:
660        case LDP_MSG_LABEL_WITHDRAW:
661            while(msg_tlen >= 4) {
662                processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
663                if (processed == 0)
664                    break;
665                msg_tlen-=processed;
666                msg_tptr+=processed;
667            }
668            break;
669
670        /*
671         *  FIXME those are the defined messages that lack a decoder
672         *  you are welcome to contribute code ;-)
673         */
674
675        case LDP_MSG_LABEL_REQUEST:
676        case LDP_MSG_LABEL_RELEASE:
677        case LDP_MSG_LABEL_ABORT_REQUEST:
678
679        default:
680            if (ndo->ndo_vflag <= 1)
681                print_unknown_data(ndo, msg_tptr, "\n\t  ", msg_tlen);
682            break;
683        }
684        /* do we want to see an additionally hexdump ? */
685        if (ndo->ndo_vflag > 1 || hexdump==TRUE)
686            print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t  ",
687                               msg_len);
688
689        tptr += msg_len+4;
690        tlen -= msg_len+4;
691    }
692    return pdu_len+4;
693trunc:
694    ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
695    return 0;
696}
697
698/*
699 * Local Variables:
700 * c-style: whitesmith
701 * c-basic-offset: 8
702 * End:
703 */
704