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/* \summary: Label Distribution Protocol (LDP) printer */
18
19#ifdef HAVE_CONFIG_H
20#include "config.h"
21#endif
22
23#include <netdissect-stdinc.h>
24
25#include "netdissect.h"
26#include "extract.h"
27#include "addrtoname.h"
28
29#include "l2vpn.h"
30#include "af.h"
31
32/*
33 * ldp common header
34 *
35 *  0                   1                   2                   3
36 *  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
37 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
38 * |  Version                      |         PDU Length            |
39 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
40 * |                         LDP Identifier                        |
41 * +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
42 * |                               |
43 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
44 *
45 */
46
47struct ldp_common_header {
48    uint8_t version[2];
49    uint8_t pdu_length[2];
50    uint8_t lsr_id[4];
51    uint8_t label_space[2];
52};
53
54#define LDP_VERSION 1
55
56/*
57 * ldp message header
58 *
59 *  0                   1                   2                   3
60 *  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
61 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
62 * |U|   Message Type              |      Message Length           |
63 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
64 * |                     Message ID                                |
65 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
66 * |                                                               |
67 * +                                                               +
68 * |                     Mandatory Parameters                      |
69 * +                                                               +
70 * |                                                               |
71 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
72 * |                                                               |
73 * +                                                               +
74 * |                     Optional Parameters                       |
75 * +                                                               +
76 * |                                                               |
77 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
78 */
79
80struct ldp_msg_header {
81    uint8_t type[2];
82    uint8_t length[2];
83    uint8_t id[4];
84};
85
86#define	LDP_MASK_MSG_TYPE(x)  ((x)&0x7fff)
87#define	LDP_MASK_U_BIT(x)     ((x)&0x8000)
88
89#define	LDP_MSG_NOTIF                0x0001
90#define	LDP_MSG_HELLO                0x0100
91#define	LDP_MSG_INIT                 0x0200
92#define	LDP_MSG_KEEPALIVE            0x0201
93#define	LDP_MSG_ADDRESS              0x0300
94#define	LDP_MSG_ADDRESS_WITHDRAW     0x0301
95#define	LDP_MSG_LABEL_MAPPING        0x0400
96#define	LDP_MSG_LABEL_REQUEST        0x0401
97#define	LDP_MSG_LABEL_WITHDRAW       0x0402
98#define	LDP_MSG_LABEL_RELEASE        0x0403
99#define	LDP_MSG_LABEL_ABORT_REQUEST  0x0404
100
101#define	LDP_VENDOR_PRIVATE_MIN       0x3e00
102#define	LDP_VENDOR_PRIVATE_MAX       0x3eff
103#define	LDP_EXPERIMENTAL_MIN         0x3f00
104#define	LDP_EXPERIMENTAL_MAX         0x3fff
105
106static const struct tok ldp_msg_values[] = {
107    { LDP_MSG_NOTIF,	             "Notification" },
108    { LDP_MSG_HELLO,	             "Hello" },
109    { LDP_MSG_INIT,	             "Initialization" },
110    { LDP_MSG_KEEPALIVE,             "Keepalive" },
111    { LDP_MSG_ADDRESS,	             "Address" },
112    { LDP_MSG_ADDRESS_WITHDRAW,	     "Address Withdraw" },
113    { LDP_MSG_LABEL_MAPPING,	     "Label Mapping" },
114    { LDP_MSG_LABEL_REQUEST,	     "Label Request" },
115    { LDP_MSG_LABEL_WITHDRAW,	     "Label Withdraw" },
116    { LDP_MSG_LABEL_RELEASE,	     "Label Release" },
117    { LDP_MSG_LABEL_ABORT_REQUEST,   "Label Abort Request" },
118    { 0, NULL}
119};
120
121#define	LDP_MASK_TLV_TYPE(x)  ((x)&0x3fff)
122#define	LDP_MASK_F_BIT(x) ((x)&0x4000)
123
124#define	LDP_TLV_FEC                  0x0100
125#define	LDP_TLV_ADDRESS_LIST         0x0101
126#define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
127#define	LDP_TLV_HOP_COUNT            0x0103
128#define	LDP_TLV_PATH_VECTOR          0x0104
129#define	LDP_TLV_GENERIC_LABEL        0x0200
130#define	LDP_TLV_ATM_LABEL            0x0201
131#define	LDP_TLV_FR_LABEL             0x0202
132#define	LDP_TLV_STATUS               0x0300
133#define	LDP_TLV_EXTD_STATUS          0x0301
134#define	LDP_TLV_RETURNED_PDU         0x0302
135#define	LDP_TLV_RETURNED_MSG         0x0303
136#define	LDP_TLV_COMMON_HELLO         0x0400
137#define	LDP_TLV_IPV4_TRANSPORT_ADDR  0x0401
138#define	LDP_TLV_CONFIG_SEQ_NUMBER    0x0402
139#define	LDP_TLV_IPV6_TRANSPORT_ADDR  0x0403
140#define	LDP_TLV_COMMON_SESSION       0x0500
141#define	LDP_TLV_ATM_SESSION_PARM     0x0501
142#define	LDP_TLV_FR_SESSION_PARM      0x0502
143#define LDP_TLV_FT_SESSION	     0x0503
144#define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
145#define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
146
147static const struct tok ldp_tlv_values[] = {
148    { LDP_TLV_FEC,	             "FEC" },
149    { LDP_TLV_ADDRESS_LIST,          "Address List" },
150    { LDP_TLV_HOP_COUNT,             "Hop Count" },
151    { LDP_TLV_PATH_VECTOR,           "Path Vector" },
152    { LDP_TLV_GENERIC_LABEL,         "Generic Label" },
153    { LDP_TLV_ATM_LABEL,             "ATM Label" },
154    { LDP_TLV_FR_LABEL,              "Frame-Relay Label" },
155    { LDP_TLV_STATUS,                "Status" },
156    { LDP_TLV_EXTD_STATUS,           "Extended Status" },
157    { LDP_TLV_RETURNED_PDU,          "Returned PDU" },
158    { LDP_TLV_RETURNED_MSG,          "Returned Message" },
159    { LDP_TLV_COMMON_HELLO,          "Common Hello Parameters" },
160    { LDP_TLV_IPV4_TRANSPORT_ADDR,   "IPv4 Transport Address" },
161    { LDP_TLV_CONFIG_SEQ_NUMBER,     "Configuration Sequence Number" },
162    { LDP_TLV_IPV6_TRANSPORT_ADDR,   "IPv6 Transport Address" },
163    { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
164    { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
165    { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
166    { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
167    { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
168    { LDP_TLV_MTU,                   "MTU" },
169    { 0, NULL}
170};
171
172#define LDP_FEC_WILDCARD	0x01
173#define LDP_FEC_PREFIX		0x02
174#define LDP_FEC_HOSTADDRESS	0x03
175/* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
176#define LDP_FEC_MARTINI_VC	0x80
177
178static const struct tok ldp_fec_values[] = {
179    { LDP_FEC_WILDCARD,		"Wildcard" },
180    { LDP_FEC_PREFIX,		"Prefix" },
181    { LDP_FEC_HOSTADDRESS,	"Host address" },
182    { LDP_FEC_MARTINI_VC,	"Martini VC" },
183    { 0, NULL}
184};
185
186#define LDP_FEC_MARTINI_IFPARM_MTU  0x01
187#define LDP_FEC_MARTINI_IFPARM_DESC 0x03
188#define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
189
190static const struct tok ldp_fec_martini_ifparm_values[] = {
191    { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
192    { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
193    { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
194    { 0, NULL}
195};
196
197/* draft-ietf-pwe3-vccv-04.txt */
198static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
199    { 0x01, "PWE3 control word" },
200    { 0x02, "MPLS Router Alert Label" },
201    { 0x04, "MPLS inner label TTL = 1" },
202    { 0, NULL}
203};
204
205/* draft-ietf-pwe3-vccv-04.txt */
206static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
207    { 0x01, "ICMP Ping" },
208    { 0x02, "LSP Ping" },
209    { 0x04, "BFD" },
210    { 0, NULL}
211};
212
213static int ldp_pdu_print(netdissect_options *, register const u_char *);
214
215/*
216 * ldp tlv header
217 *
218 *  0                   1                   2                   3
219 *  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
220 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
221 * |U|F|        Type               |            Length             |
222 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
223 * |                                                               |
224 * |                             Value                             |
225 * ~                                                               ~
226 * |                                                               |
227 * |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
228 * |                               |
229 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
230 */
231
232#define TLV_TCHECK(minlen) \
233    ND_TCHECK2(*tptr, minlen); if (tlv_tlen < minlen) goto badtlv;
234
235static int
236ldp_tlv_print(netdissect_options *ndo,
237              register const u_char *tptr,
238              u_short msg_tlen)
239{
240    struct ldp_tlv_header {
241        uint8_t type[2];
242        uint8_t length[2];
243    };
244
245    const struct ldp_tlv_header *ldp_tlv_header;
246    u_short tlv_type,tlv_len,tlv_tlen,af,ft_flags;
247    u_char fec_type;
248    u_int ui,vc_info_len, vc_info_tlv_type, vc_info_tlv_len,idx;
249    char buf[100];
250    int i;
251
252    ldp_tlv_header = (const struct ldp_tlv_header *)tptr;
253    ND_TCHECK(*ldp_tlv_header);
254    tlv_len=EXTRACT_16BITS(ldp_tlv_header->length);
255    if (tlv_len + 4 > msg_tlen) {
256        ND_PRINT((ndo, "\n\t\t TLV contents go past end of message"));
257        return 0;
258    }
259    tlv_tlen=tlv_len;
260    tlv_type=LDP_MASK_TLV_TYPE(EXTRACT_16BITS(ldp_tlv_header->type));
261
262    /* FIXME vendor private / experimental check */
263    ND_PRINT((ndo, "\n\t    %s TLV (0x%04x), length: %u, Flags: [%s and %s forward if unknown]",
264           tok2str(ldp_tlv_values,
265                   "Unknown",
266                   tlv_type),
267           tlv_type,
268           tlv_len,
269           LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "continue processing" : "ignore",
270           LDP_MASK_F_BIT(EXTRACT_16BITS(&ldp_tlv_header->type)) ? "do" : "don't"));
271
272    tptr+=sizeof(struct ldp_tlv_header);
273
274    switch(tlv_type) {
275
276    case LDP_TLV_COMMON_HELLO:
277        TLV_TCHECK(4);
278        ND_PRINT((ndo, "\n\t      Hold Time: %us, Flags: [%s Hello%s]",
279               EXTRACT_16BITS(tptr),
280               (EXTRACT_16BITS(tptr+2)&0x8000) ? "Targeted" : "Link",
281               (EXTRACT_16BITS(tptr+2)&0x4000) ? ", Request for targeted Hellos" : ""));
282        break;
283
284    case LDP_TLV_IPV4_TRANSPORT_ADDR:
285        TLV_TCHECK(4);
286        ND_PRINT((ndo, "\n\t      IPv4 Transport Address: %s", ipaddr_string(ndo, tptr)));
287        break;
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    case LDP_TLV_CONFIG_SEQ_NUMBER:
293        TLV_TCHECK(4);
294        ND_PRINT((ndo, "\n\t      Sequence Number: %u", EXTRACT_32BITS(tptr)));
295        break;
296
297    case LDP_TLV_ADDRESS_LIST:
298        TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
299	af = EXTRACT_16BITS(tptr);
300	tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
301        tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
302	ND_PRINT((ndo, "\n\t      Address Family: %s, addresses",
303               tok2str(af_values, "Unknown (%u)", af)));
304        switch (af) {
305        case AFNUM_INET:
306	    while(tlv_tlen >= sizeof(struct in_addr)) {
307		ND_TCHECK2(*tptr, sizeof(struct in_addr));
308		ND_PRINT((ndo, " %s", ipaddr_string(ndo, tptr)));
309		tlv_tlen-=sizeof(struct in_addr);
310		tptr+=sizeof(struct in_addr);
311	    }
312            break;
313        case AFNUM_INET6:
314	    while(tlv_tlen >= sizeof(struct in6_addr)) {
315		ND_TCHECK2(*tptr, sizeof(struct in6_addr));
316		ND_PRINT((ndo, " %s", ip6addr_string(ndo, tptr)));
317		tlv_tlen-=sizeof(struct in6_addr);
318		tptr+=sizeof(struct in6_addr);
319	    }
320            break;
321        default:
322            /* unknown AF */
323            break;
324        }
325	break;
326
327    case LDP_TLV_COMMON_SESSION:
328	TLV_TCHECK(8);
329	ND_PRINT((ndo, "\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
330	       EXTRACT_16BITS(tptr), EXTRACT_16BITS(tptr+2),
331	       (EXTRACT_16BITS(tptr+6)&0x8000) ? "On Demand" : "Unsolicited",
332	       (EXTRACT_16BITS(tptr+6)&0x4000) ? "Enabled" : "Disabled"
333	       ));
334	break;
335
336    case LDP_TLV_FEC:
337        TLV_TCHECK(1);
338        fec_type = *tptr;
339	ND_PRINT((ndo, "\n\t      %s FEC (0x%02x)",
340	       tok2str(ldp_fec_values, "Unknown", fec_type),
341	       fec_type));
342
343	tptr+=1;
344	tlv_tlen-=1;
345	switch(fec_type) {
346
347	case LDP_FEC_WILDCARD:
348	    break;
349	case LDP_FEC_PREFIX:
350	    TLV_TCHECK(2);
351	    af = EXTRACT_16BITS(tptr);
352	    tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
353	    tlv_tlen-=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
354	    if (af == AFNUM_INET) {
355		i=decode_prefix4(ndo, tptr, tlv_tlen, buf, sizeof(buf));
356		if (i == -2)
357		    goto trunc;
358		if (i == -3)
359		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
360		else if (i == -1)
361		    ND_PRINT((ndo, ": IPv4 prefix (invalid length)"));
362		else
363		    ND_PRINT((ndo, ": IPv4 prefix %s", buf));
364	    }
365	    else if (af == AFNUM_INET6) {
366		i=decode_prefix6(ndo, tptr, tlv_tlen, buf, sizeof(buf));
367		if (i == -2)
368		    goto trunc;
369		if (i == -3)
370		    ND_PRINT((ndo, ": IPv4 prefix (goes past end of TLV)"));
371		else if (i == -1)
372		    ND_PRINT((ndo, ": IPv6 prefix (invalid length)"));
373		else
374		    ND_PRINT((ndo, ": IPv6 prefix %s", buf));
375	    }
376	    else
377		ND_PRINT((ndo, ": Address family %u prefix", af));
378	    break;
379	case LDP_FEC_HOSTADDRESS:
380	    break;
381	case LDP_FEC_MARTINI_VC:
382            /*
383             * We assume the type was supposed to be one of the MPLS
384             * Pseudowire Types.
385             */
386            TLV_TCHECK(7);
387            vc_info_len = *(tptr+2);
388
389            /*
390	     * According to RFC 4908, the VC info Length field can be zero,
391	     * in which case not only are there no interface parameters,
392	     * there's no VC ID.
393	     */
394            if (vc_info_len == 0) {
395                ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-info-length: %u",
396                       tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
397                       EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
398                       EXTRACT_32BITS(tptr+3),
399                       vc_info_len));
400                break;
401            }
402
403            /* Make sure we have the VC ID as well */
404            TLV_TCHECK(11);
405	    ND_PRINT((ndo, ": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
406		   tok2str(mpls_pw_types_values, "Unknown", EXTRACT_16BITS(tptr)&0x7fff),
407		   EXTRACT_16BITS(tptr)&0x8000 ? "" : "no ",
408                   EXTRACT_32BITS(tptr+3),
409		   EXTRACT_32BITS(tptr+7),
410                   vc_info_len));
411            if (vc_info_len < 4) {
412                /* minimum 4, for the VC ID */
413                ND_PRINT((ndo, " (invalid, < 4"));
414                return(tlv_len+4); /* Type & Length fields not included */
415	    }
416            vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
417
418            /* Skip past the fixed information and the VC ID */
419            tptr+=11;
420            tlv_tlen-=11;
421            TLV_TCHECK(vc_info_len);
422
423            while (vc_info_len > 2) {
424                vc_info_tlv_type = *tptr;
425                vc_info_tlv_len = *(tptr+1);
426                if (vc_info_tlv_len < 2)
427                    break;
428                if (vc_info_len < vc_info_tlv_len)
429                    break;
430
431                ND_PRINT((ndo, "\n\t\tInterface Parameter: %s (0x%02x), len %u",
432                       tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
433                       vc_info_tlv_type,
434                       vc_info_tlv_len));
435
436                switch(vc_info_tlv_type) {
437                case LDP_FEC_MARTINI_IFPARM_MTU:
438                    ND_PRINT((ndo, ": %u", EXTRACT_16BITS(tptr+2)));
439                    break;
440
441                case LDP_FEC_MARTINI_IFPARM_DESC:
442                    ND_PRINT((ndo, ": "));
443                    for (idx = 2; idx < vc_info_tlv_len; idx++)
444                        safeputchar(ndo, *(tptr + idx));
445                    break;
446
447                case LDP_FEC_MARTINI_IFPARM_VCCV:
448                    ND_PRINT((ndo, "\n\t\t  Control Channels (0x%02x) = [%s]",
449                           *(tptr+2),
450                           bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", *(tptr+2))));
451                    ND_PRINT((ndo, "\n\t\t  CV Types (0x%02x) = [%s]",
452                           *(tptr+3),
453                           bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", *(tptr+3))));
454                    break;
455
456                default:
457                    print_unknown_data(ndo, tptr+2, "\n\t\t  ", vc_info_tlv_len-2);
458                    break;
459                }
460
461                vc_info_len -= vc_info_tlv_len;
462                tptr += vc_info_tlv_len;
463            }
464	    break;
465	}
466
467	break;
468
469    case LDP_TLV_GENERIC_LABEL:
470	TLV_TCHECK(4);
471	ND_PRINT((ndo, "\n\t      Label: %u", EXTRACT_32BITS(tptr) & 0xfffff));
472	break;
473
474    case LDP_TLV_STATUS:
475	TLV_TCHECK(8);
476	ui = EXTRACT_32BITS(tptr);
477	tptr+=4;
478	ND_PRINT((ndo, "\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
479	       ui&0x3fffffff,
480	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
481	       ui&0x40000000 ? "do" : "don't"));
482	ui = EXTRACT_32BITS(tptr);
483	tptr+=4;
484	if (ui)
485	    ND_PRINT((ndo, ", causing Message ID: 0x%08x", ui));
486	break;
487
488    case LDP_TLV_FT_SESSION:
489	TLV_TCHECK(8);
490	ft_flags = EXTRACT_16BITS(tptr);
491	ND_PRINT((ndo, "\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
492	       ft_flags&0x8000 ? "" : "No ",
493	       ft_flags&0x8 ? "" : "Don't ",
494	       ft_flags&0x4 ? "" : "No ",
495	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
496	       ft_flags&0x1 ? "" : "Don't "));
497	tptr+=4;
498	ui = EXTRACT_32BITS(tptr);
499	if (ui)
500	    ND_PRINT((ndo, ", Reconnect Timeout: %ums", ui));
501	tptr+=4;
502	ui = EXTRACT_32BITS(tptr);
503	if (ui)
504	    ND_PRINT((ndo, ", Recovery Time: %ums", ui));
505	break;
506
507    case LDP_TLV_MTU:
508	TLV_TCHECK(2);
509	ND_PRINT((ndo, "\n\t      MTU: %u", EXTRACT_16BITS(tptr)));
510	break;
511
512
513    /*
514     *  FIXME those are the defined TLVs that lack a decoder
515     *  you are welcome to contribute code ;-)
516     */
517
518    case LDP_TLV_HOP_COUNT:
519    case LDP_TLV_PATH_VECTOR:
520    case LDP_TLV_ATM_LABEL:
521    case LDP_TLV_FR_LABEL:
522    case LDP_TLV_EXTD_STATUS:
523    case LDP_TLV_RETURNED_PDU:
524    case LDP_TLV_RETURNED_MSG:
525    case LDP_TLV_ATM_SESSION_PARM:
526    case LDP_TLV_FR_SESSION_PARM:
527    case LDP_TLV_LABEL_REQUEST_MSG_ID:
528
529    default:
530        if (ndo->ndo_vflag <= 1)
531            print_unknown_data(ndo, tptr, "\n\t      ", tlv_tlen);
532        break;
533    }
534    return(tlv_len+4); /* Type & Length fields not included */
535
536trunc:
537    ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
538    return 0;
539
540badtlv:
541    ND_PRINT((ndo, "\n\t\t TLV contents go past end of TLV"));
542    return(tlv_len+4); /* Type & Length fields not included */
543}
544
545void
546ldp_print(netdissect_options *ndo,
547          register const u_char *pptr, register u_int len)
548{
549    int processed;
550    while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
551        processed = ldp_pdu_print(ndo, pptr);
552        if (processed == 0)
553            return;
554        len -= processed;
555        pptr += processed;
556    }
557}
558
559static int
560ldp_pdu_print(netdissect_options *ndo,
561              register const u_char *pptr)
562{
563    const struct ldp_common_header *ldp_com_header;
564    const struct ldp_msg_header *ldp_msg_header;
565    const u_char *tptr,*msg_tptr;
566    u_short tlen;
567    u_short pdu_len,msg_len,msg_type,msg_tlen;
568    int hexdump,processed;
569
570    ldp_com_header = (const struct ldp_common_header *)pptr;
571    ND_TCHECK(*ldp_com_header);
572
573    /*
574     * Sanity checking of the header.
575     */
576    if (EXTRACT_16BITS(&ldp_com_header->version) != LDP_VERSION) {
577	ND_PRINT((ndo, "%sLDP version %u packet not supported",
578               (ndo->ndo_vflag < 1) ? "" : "\n\t",
579               EXTRACT_16BITS(&ldp_com_header->version)));
580	return 0;
581    }
582
583    pdu_len = EXTRACT_16BITS(&ldp_com_header->pdu_length);
584    if (pdu_len < sizeof(const struct ldp_common_header)-4) {
585        /* length too short */
586        ND_PRINT((ndo, "%sLDP, pdu-length: %u (too short, < %u)",
587               (ndo->ndo_vflag < 1) ? "" : "\n\t",
588               pdu_len,
589               (u_int)(sizeof(const struct ldp_common_header)-4)));
590        return 0;
591    }
592
593    /* print the LSR-ID, label-space & length */
594    ND_PRINT((ndo, "%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
595           (ndo->ndo_vflag < 1) ? "" : "\n\t",
596           ipaddr_string(ndo, &ldp_com_header->lsr_id),
597           EXTRACT_16BITS(&ldp_com_header->label_space),
598           pdu_len));
599
600    /* bail out if non-verbose */
601    if (ndo->ndo_vflag < 1)
602        return 0;
603
604    /* ok they seem to want to know everything - lets fully decode it */
605    tptr = pptr + sizeof(const struct ldp_common_header);
606    tlen = pdu_len - (sizeof(const struct ldp_common_header)-4);	/* Type & Length fields not included */
607
608    while(tlen>0) {
609        /* did we capture enough for fully decoding the msg header ? */
610        ND_TCHECK2(*tptr, sizeof(struct ldp_msg_header));
611
612        ldp_msg_header = (const struct ldp_msg_header *)tptr;
613        msg_len=EXTRACT_16BITS(ldp_msg_header->length);
614        msg_type=LDP_MASK_MSG_TYPE(EXTRACT_16BITS(ldp_msg_header->type));
615
616        if (msg_len < sizeof(struct ldp_msg_header)-4) {
617            /* length too short */
618            /* FIXME vendor private / experimental check */
619            ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u (too short, < %u)",
620                   tok2str(ldp_msg_values,
621                           "Unknown",
622                           msg_type),
623                   msg_type,
624                   msg_len,
625                   (u_int)(sizeof(struct ldp_msg_header)-4)));
626            return 0;
627        }
628
629        /* FIXME vendor private / experimental check */
630        ND_PRINT((ndo, "\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
631               tok2str(ldp_msg_values,
632                       "Unknown",
633                       msg_type),
634               msg_type,
635               msg_len,
636               EXTRACT_32BITS(&ldp_msg_header->id),
637               LDP_MASK_U_BIT(EXTRACT_16BITS(&ldp_msg_header->type)) ? "continue processing" : "ignore"));
638
639        msg_tptr=tptr+sizeof(struct ldp_msg_header);
640        msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
641
642        /* did we capture enough for fully decoding the message ? */
643        ND_TCHECK2(*tptr, msg_len);
644        hexdump=FALSE;
645
646        switch(msg_type) {
647
648        case LDP_MSG_NOTIF:
649        case LDP_MSG_HELLO:
650        case LDP_MSG_INIT:
651        case LDP_MSG_KEEPALIVE:
652        case LDP_MSG_ADDRESS:
653        case LDP_MSG_LABEL_MAPPING:
654        case LDP_MSG_ADDRESS_WITHDRAW:
655        case LDP_MSG_LABEL_WITHDRAW:
656            while(msg_tlen >= 4) {
657                processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
658                if (processed == 0)
659                    break;
660                msg_tlen-=processed;
661                msg_tptr+=processed;
662            }
663            break;
664
665        /*
666         *  FIXME those are the defined messages that lack a decoder
667         *  you are welcome to contribute code ;-)
668         */
669
670        case LDP_MSG_LABEL_REQUEST:
671        case LDP_MSG_LABEL_RELEASE:
672        case LDP_MSG_LABEL_ABORT_REQUEST:
673
674        default:
675            if (ndo->ndo_vflag <= 1)
676                print_unknown_data(ndo, msg_tptr, "\n\t  ", msg_tlen);
677            break;
678        }
679        /* do we want to see an additionally hexdump ? */
680        if (ndo->ndo_vflag > 1 || hexdump==TRUE)
681            print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t  ",
682                               msg_len);
683
684        tptr += msg_len+4;
685        tlen -= msg_len+4;
686    }
687    return pdu_len+4;
688trunc:
689    ND_PRINT((ndo, "\n\t\t packet exceeded snapshot"));
690    return 0;
691}
692
693/*
694 * Local Variables:
695 * c-style: whitesmith
696 * c-basic-offset: 8
697 * End:
698 */
699