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@gredler.at)
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/*
34 * ldp common header
35 *
36 *  0                   1                   2                   3
37 *  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
38 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39 * |  Version                      |         PDU Length            |
40 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41 * |                         LDP Identifier                        |
42 * +                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43 * |                               |
44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45 *
46 */
47
48struct ldp_common_header {
49    nd_uint16_t version;
50    nd_uint16_t pdu_length;
51    nd_ipv4     lsr_id;
52    nd_uint16_t label_space;
53};
54
55#define LDP_VERSION 1
56
57/*
58 * ldp message header
59 *
60 *  0                   1                   2                   3
61 *  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
62 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
63 * |U|   Message Type              |      Message Length           |
64 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
65 * |                     Message ID                                |
66 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
67 * |                                                               |
68 * +                                                               +
69 * |                     Mandatory Parameters                      |
70 * +                                                               +
71 * |                                                               |
72 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
73 * |                                                               |
74 * +                                                               +
75 * |                     Optional Parameters                       |
76 * +                                                               +
77 * |                                                               |
78 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
79 */
80
81struct ldp_msg_header {
82    nd_uint16_t type;
83    nd_uint16_t length;
84    nd_uint32_t id;
85};
86
87#define	LDP_MASK_MSG_TYPE(x)  ((x)&0x7fff)
88#define	LDP_MASK_U_BIT(x)     ((x)&0x8000)
89
90#define	LDP_MSG_NOTIF                0x0001
91#define	LDP_MSG_HELLO                0x0100
92#define	LDP_MSG_INIT                 0x0200
93#define	LDP_MSG_KEEPALIVE            0x0201
94#define	LDP_MSG_ADDRESS              0x0300
95#define	LDP_MSG_ADDRESS_WITHDRAW     0x0301
96#define	LDP_MSG_LABEL_MAPPING        0x0400
97#define	LDP_MSG_LABEL_REQUEST        0x0401
98#define	LDP_MSG_LABEL_WITHDRAW       0x0402
99#define	LDP_MSG_LABEL_RELEASE        0x0403
100#define	LDP_MSG_LABEL_ABORT_REQUEST  0x0404
101
102#define	LDP_VENDOR_PRIVATE_MIN       0x3e00
103#define	LDP_VENDOR_PRIVATE_MAX       0x3eff
104#define	LDP_EXPERIMENTAL_MIN         0x3f00
105#define	LDP_EXPERIMENTAL_MAX         0x3fff
106
107static const struct tok ldp_msg_values[] = {
108    { LDP_MSG_NOTIF,	             "Notification" },
109    { LDP_MSG_HELLO,	             "Hello" },
110    { LDP_MSG_INIT,	             "Initialization" },
111    { LDP_MSG_KEEPALIVE,             "Keepalive" },
112    { LDP_MSG_ADDRESS,	             "Address" },
113    { LDP_MSG_ADDRESS_WITHDRAW,	     "Address Withdraw" },
114    { LDP_MSG_LABEL_MAPPING,	     "Label Mapping" },
115    { LDP_MSG_LABEL_REQUEST,	     "Label Request" },
116    { LDP_MSG_LABEL_WITHDRAW,	     "Label Withdraw" },
117    { LDP_MSG_LABEL_RELEASE,	     "Label Release" },
118    { LDP_MSG_LABEL_ABORT_REQUEST,   "Label Abort Request" },
119    { 0, NULL}
120};
121
122#define	LDP_MASK_TLV_TYPE(x)  ((x)&0x3fff)
123#define	LDP_MASK_F_BIT(x) ((x)&0x4000)
124
125#define	LDP_TLV_FEC                  0x0100
126#define	LDP_TLV_ADDRESS_LIST         0x0101
127#define LDP_TLV_ADDRESS_LIST_AFNUM_LEN 2
128#define	LDP_TLV_HOP_COUNT            0x0103
129#define	LDP_TLV_PATH_VECTOR          0x0104
130#define	LDP_TLV_GENERIC_LABEL        0x0200
131#define	LDP_TLV_ATM_LABEL            0x0201
132#define	LDP_TLV_FR_LABEL             0x0202
133#define	LDP_TLV_STATUS               0x0300
134#define	LDP_TLV_EXTD_STATUS          0x0301
135#define	LDP_TLV_RETURNED_PDU         0x0302
136#define	LDP_TLV_RETURNED_MSG         0x0303
137#define	LDP_TLV_COMMON_HELLO         0x0400
138#define	LDP_TLV_IPV4_TRANSPORT_ADDR  0x0401
139#define	LDP_TLV_CONFIG_SEQ_NUMBER    0x0402
140#define	LDP_TLV_IPV6_TRANSPORT_ADDR  0x0403
141#define	LDP_TLV_COMMON_SESSION       0x0500
142#define	LDP_TLV_ATM_SESSION_PARM     0x0501
143#define	LDP_TLV_FR_SESSION_PARM      0x0502
144#define LDP_TLV_FT_SESSION	     0x0503
145#define	LDP_TLV_LABEL_REQUEST_MSG_ID 0x0600
146#define LDP_TLV_MTU                  0x0601 /* rfc 3988 */
147
148static const struct tok ldp_tlv_values[] = {
149    { LDP_TLV_FEC,	             "FEC" },
150    { LDP_TLV_ADDRESS_LIST,          "Address List" },
151    { LDP_TLV_HOP_COUNT,             "Hop Count" },
152    { LDP_TLV_PATH_VECTOR,           "Path Vector" },
153    { LDP_TLV_GENERIC_LABEL,         "Generic Label" },
154    { LDP_TLV_ATM_LABEL,             "ATM Label" },
155    { LDP_TLV_FR_LABEL,              "Frame-Relay Label" },
156    { LDP_TLV_STATUS,                "Status" },
157    { LDP_TLV_EXTD_STATUS,           "Extended Status" },
158    { LDP_TLV_RETURNED_PDU,          "Returned PDU" },
159    { LDP_TLV_RETURNED_MSG,          "Returned Message" },
160    { LDP_TLV_COMMON_HELLO,          "Common Hello Parameters" },
161    { LDP_TLV_IPV4_TRANSPORT_ADDR,   "IPv4 Transport Address" },
162    { LDP_TLV_CONFIG_SEQ_NUMBER,     "Configuration Sequence Number" },
163    { LDP_TLV_IPV6_TRANSPORT_ADDR,   "IPv6 Transport Address" },
164    { LDP_TLV_COMMON_SESSION,        "Common Session Parameters" },
165    { LDP_TLV_ATM_SESSION_PARM,      "ATM Session Parameters" },
166    { LDP_TLV_FR_SESSION_PARM,       "Frame-Relay Session Parameters" },
167    { LDP_TLV_FT_SESSION,            "Fault-Tolerant Session Parameters" },
168    { LDP_TLV_LABEL_REQUEST_MSG_ID,  "Label Request Message ID" },
169    { LDP_TLV_MTU,                   "MTU" },
170    { 0, NULL}
171};
172
173#define LDP_FEC_WILDCARD	0x01
174#define LDP_FEC_PREFIX		0x02
175#define LDP_FEC_HOSTADDRESS	0x03
176/* From RFC 4906; should probably be updated to RFC 4447 (e.g., VC -> PW) */
177#define LDP_FEC_MARTINI_VC	0x80
178
179static const struct tok ldp_fec_values[] = {
180    { LDP_FEC_WILDCARD,		"Wildcard" },
181    { LDP_FEC_PREFIX,		"Prefix" },
182    { LDP_FEC_HOSTADDRESS,	"Host address" },
183    { LDP_FEC_MARTINI_VC,	"Martini VC" },
184    { 0, NULL}
185};
186
187#define LDP_FEC_MARTINI_IFPARM_MTU  0x01
188#define LDP_FEC_MARTINI_IFPARM_DESC 0x03
189#define LDP_FEC_MARTINI_IFPARM_VCCV 0x0c
190
191static const struct tok ldp_fec_martini_ifparm_values[] = {
192    { LDP_FEC_MARTINI_IFPARM_MTU, "MTU" },
193    { LDP_FEC_MARTINI_IFPARM_DESC, "Description" },
194    { LDP_FEC_MARTINI_IFPARM_VCCV, "VCCV" },
195    { 0, NULL}
196};
197
198/* draft-ietf-pwe3-vccv-04.txt */
199static const struct tok ldp_fec_martini_ifparm_vccv_cc_values[] = {
200    { 0x01, "PWE3 control word" },
201    { 0x02, "MPLS Router Alert Label" },
202    { 0x04, "MPLS inner label TTL = 1" },
203    { 0, NULL}
204};
205
206/* draft-ietf-pwe3-vccv-04.txt */
207static const struct tok ldp_fec_martini_ifparm_vccv_cv_values[] = {
208    { 0x01, "ICMP Ping" },
209    { 0x02, "LSP Ping" },
210    { 0x04, "BFD" },
211    { 0, NULL}
212};
213
214static u_int ldp_pdu_print(netdissect_options *, const u_char *);
215
216/*
217 * ldp tlv header
218 *
219 *  0                   1                   2                   3
220 *  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
221 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
222 * |U|F|        Type               |            Length             |
223 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
224 * |                                                               |
225 * |                             Value                             |
226 * ~                                                               ~
227 * |                                                               |
228 * |                               +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
229 * |                               |
230 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
231 */
232
233#define TLV_TCHECK(minlen) \
234    if (tlv_tlen < minlen) { \
235        ND_PRINT(" [tlv length %u < %u]", tlv_tlen, minlen); \
236        nd_print_invalid(ndo); \
237        goto invalid; \
238    }
239
240static u_int
241ldp_tlv_print(netdissect_options *ndo,
242              const u_char *tptr,
243              u_int msg_tlen)
244{
245    struct ldp_tlv_header {
246        nd_uint16_t type;
247        nd_uint16_t length;
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_SIZE(ldp_tlv_header);
259    tlv_len=GET_BE_U_2(ldp_tlv_header->length);
260    if (tlv_len + 4U > msg_tlen) {
261        ND_PRINT("\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(GET_BE_U_2(ldp_tlv_header->type));
266
267    /* FIXME vendor private / experimental check */
268    ND_PRINT("\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(GET_BE_U_2(ldp_tlv_header->type)) ? "continue processing" : "ignore",
275           LDP_MASK_F_BIT(GET_BE_U_2(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("\n\t      Hold Time: %us, Flags: [%s Hello%s]",
284               GET_BE_U_2(tptr),
285               (GET_BE_U_2(tptr + 2)&0x8000) ? "Targeted" : "Link",
286               (GET_BE_U_2(tptr + 2)&0x4000) ? ", Request for targeted Hellos" : "");
287        break;
288
289    case LDP_TLV_IPV4_TRANSPORT_ADDR:
290        TLV_TCHECK(4);
291        ND_PRINT("\n\t      IPv4 Transport Address: %s", GET_IPADDR_STRING(tptr));
292        break;
293    case LDP_TLV_IPV6_TRANSPORT_ADDR:
294        TLV_TCHECK(16);
295        ND_PRINT("\n\t      IPv6 Transport Address: %s", GET_IP6ADDR_STRING(tptr));
296        break;
297    case LDP_TLV_CONFIG_SEQ_NUMBER:
298        TLV_TCHECK(4);
299        ND_PRINT("\n\t      Sequence Number: %u", GET_BE_U_4(tptr));
300        break;
301
302    case LDP_TLV_ADDRESS_LIST:
303        TLV_TCHECK(LDP_TLV_ADDRESS_LIST_AFNUM_LEN);
304	af = GET_BE_U_2(tptr);
305	tptr+=LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
306        tlv_tlen -= LDP_TLV_ADDRESS_LIST_AFNUM_LEN;
307	ND_PRINT("\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(nd_ipv4)) {
312		ND_PRINT(" %s", GET_IPADDR_STRING(tptr));
313		tlv_tlen-=sizeof(nd_ipv4);
314		tptr+=sizeof(nd_ipv4);
315	    }
316            break;
317        case AFNUM_INET6:
318	    while(tlv_tlen >= sizeof(nd_ipv6)) {
319		ND_PRINT(" %s", GET_IP6ADDR_STRING(tptr));
320		tlv_tlen-=sizeof(nd_ipv6);
321		tptr+=sizeof(nd_ipv6);
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("\n\t      Version: %u, Keepalive: %us, Flags: [Downstream %s, Loop Detection %s]",
333	       GET_BE_U_2(tptr), GET_BE_U_2(tptr + 2),
334	       (GET_BE_U_2(tptr + 6)&0x8000) ? "On Demand" : "Unsolicited",
335	       (GET_BE_U_2(tptr + 6)&0x4000) ? "Enabled" : "Disabled"
336	       );
337	break;
338
339    case LDP_TLV_FEC:
340        TLV_TCHECK(1);
341        fec_type = GET_U_1(tptr);
342	ND_PRINT("\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 = GET_BE_U_2(tptr);
355	    tptr+=2;
356	    tlv_tlen-=2;
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(": IPv4 prefix (goes past end of TLV)");
363		else if (i == -1)
364		    ND_PRINT(": IPv4 prefix (invalid length)");
365		else
366		    ND_PRINT(": 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(": IPv4 prefix (goes past end of TLV)");
374		else if (i == -1)
375		    ND_PRINT(": IPv6 prefix (invalid length)");
376		else
377		    ND_PRINT(": IPv6 prefix %s", buf);
378	    }
379	    else
380		ND_PRINT(": Address family %u prefix", af);
381	    break;
382	case LDP_FEC_HOSTADDRESS:
383	    break;
384	case LDP_FEC_MARTINI_VC:
385            /*
386             * We assume the type was supposed to be one of the MPLS
387             * Pseudowire Types.
388             */
389            TLV_TCHECK(7);
390            vc_info_len = GET_U_1(tptr + 2);
391
392            /*
393	     * According to RFC 4908, the VC info Length field can be zero,
394	     * in which case not only are there no interface parameters,
395	     * there's no VC ID.
396	     */
397            if (vc_info_len == 0) {
398                ND_PRINT(": %s, %scontrol word, group-ID %u, VC-info-length: %u",
399                       tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
400                       GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
401                       GET_BE_U_4(tptr + 3),
402                       vc_info_len);
403                break;
404            }
405
406            /* Make sure we have the VC ID as well */
407            TLV_TCHECK(11);
408	    ND_PRINT(": %s, %scontrol word, group-ID %u, VC-ID %u, VC-info-length: %u",
409		   tok2str(mpls_pw_types_values, "Unknown", GET_BE_U_2(tptr)&0x7fff),
410		   GET_BE_U_2(tptr)&0x8000 ? "" : "no ",
411		   GET_BE_U_4(tptr + 3),
412		   GET_BE_U_4(tptr + 7),
413		   vc_info_len);
414            if (vc_info_len < 4) {
415                /* minimum 4, for the VC ID */
416                ND_PRINT(" (invalid, < 4");
417                return(tlv_len+4); /* Type & Length fields not included */
418	    }
419            vc_info_len -= 4; /* subtract out the VC ID, giving the length of the interface parameters */
420
421            /* Skip past the fixed information and the VC ID */
422            tptr+=11;
423            tlv_tlen-=11;
424            TLV_TCHECK(vc_info_len);
425
426            while (vc_info_len > 2) {
427                vc_info_tlv_type = GET_U_1(tptr);
428                vc_info_tlv_len = GET_U_1(tptr + 1);
429                if (vc_info_tlv_len < 2)
430                    break;
431                if (vc_info_len < vc_info_tlv_len)
432                    break;
433
434                ND_PRINT("\n\t\tInterface Parameter: %s (0x%02x), len %u",
435                       tok2str(ldp_fec_martini_ifparm_values,"Unknown",vc_info_tlv_type),
436                       vc_info_tlv_type,
437                       vc_info_tlv_len);
438
439                switch(vc_info_tlv_type) {
440                case LDP_FEC_MARTINI_IFPARM_MTU:
441                    ND_PRINT(": %u", GET_BE_U_2(tptr + 2));
442                    break;
443
444                case LDP_FEC_MARTINI_IFPARM_DESC:
445                    ND_PRINT(": ");
446                    for (idx = 2; idx < vc_info_tlv_len; idx++)
447                        fn_print_char(ndo, GET_U_1(tptr + idx));
448                    break;
449
450                case LDP_FEC_MARTINI_IFPARM_VCCV:
451                    ND_PRINT("\n\t\t  Control Channels (0x%02x) = [%s]",
452                           GET_U_1((tptr + 2)),
453                           bittok2str(ldp_fec_martini_ifparm_vccv_cc_values, "none", GET_U_1((tptr + 2))));
454                    ND_PRINT("\n\t\t  CV Types (0x%02x) = [%s]",
455                           GET_U_1((tptr + 3)),
456                           bittok2str(ldp_fec_martini_ifparm_vccv_cv_values, "none", GET_U_1((tptr + 3))));
457                    break;
458
459                default:
460                    print_unknown_data(ndo, tptr+2, "\n\t\t  ", vc_info_tlv_len-2);
461                    break;
462                }
463
464                vc_info_len -= vc_info_tlv_len;
465                tptr += vc_info_tlv_len;
466            }
467	    break;
468	}
469
470	break;
471
472    case LDP_TLV_GENERIC_LABEL:
473	TLV_TCHECK(4);
474	ND_PRINT("\n\t      Label: %u", GET_BE_U_4(tptr) & 0xfffff);
475	break;
476
477    case LDP_TLV_STATUS:
478	TLV_TCHECK(8);
479	ui = GET_BE_U_4(tptr);
480	tptr+=4;
481	ND_PRINT("\n\t      Status: 0x%02x, Flags: [%s and %s forward]",
482	       ui&0x3fffffff,
483	       ui&0x80000000 ? "Fatal error" : "Advisory Notification",
484	       ui&0x40000000 ? "do" : "don't");
485	ui = GET_BE_U_4(tptr);
486	tptr+=4;
487	if (ui)
488	    ND_PRINT(", causing Message ID: 0x%08x", ui);
489	break;
490
491    case LDP_TLV_FT_SESSION:
492	TLV_TCHECK(12);
493	ft_flags = GET_BE_U_2(tptr);
494	ND_PRINT("\n\t      Flags: [%sReconnect, %sSave State, %sAll-Label Protection, %s Checkpoint, %sRe-Learn State]",
495	       ft_flags&0x8000 ? "" : "No ",
496	       ft_flags&0x8 ? "" : "Don't ",
497	       ft_flags&0x4 ? "" : "No ",
498	       ft_flags&0x2 ? "Sequence Numbered Label" : "All Labels",
499	       ft_flags&0x1 ? "" : "Don't ");
500	/* 16 bits (FT Flags) + 16 bits (Reserved) */
501	tptr+=4;
502	ui = GET_BE_U_4(tptr);
503	if (ui)
504	    ND_PRINT(", Reconnect Timeout: %ums", ui);
505	tptr+=4;
506	ui = GET_BE_U_4(tptr);
507	if (ui)
508	    ND_PRINT(", Recovery Time: %ums", ui);
509	break;
510
511    case LDP_TLV_MTU:
512	TLV_TCHECK(2);
513	ND_PRINT("\n\t      MTU: %u", GET_BE_U_2(tptr));
514	break;
515
516
517    /*
518     *  FIXME those are the defined TLVs that lack a decoder
519     *  you are welcome to contribute code ;-)
520     */
521
522    case LDP_TLV_HOP_COUNT:
523    case LDP_TLV_PATH_VECTOR:
524    case LDP_TLV_ATM_LABEL:
525    case LDP_TLV_FR_LABEL:
526    case LDP_TLV_EXTD_STATUS:
527    case LDP_TLV_RETURNED_PDU:
528    case LDP_TLV_RETURNED_MSG:
529    case LDP_TLV_ATM_SESSION_PARM:
530    case LDP_TLV_FR_SESSION_PARM:
531    case LDP_TLV_LABEL_REQUEST_MSG_ID:
532
533    default:
534        if (ndo->ndo_vflag <= 1)
535            print_unknown_data(ndo, tptr, "\n\t      ", tlv_tlen);
536        break;
537    }
538    return(tlv_len+4); /* Type & Length fields not included */
539
540trunc:
541    nd_trunc_longjmp(ndo);
542
543invalid:
544    return(tlv_len+4); /* Type & Length fields not included */
545}
546
547void
548ldp_print(netdissect_options *ndo,
549          const u_char *pptr, u_int len)
550{
551    u_int processed;
552
553    ndo->ndo_protocol = "ldp";
554    while (len > (sizeof(struct ldp_common_header) + sizeof(struct ldp_msg_header))) {
555        processed = ldp_pdu_print(ndo, pptr);
556        if (processed == 0)
557            return;
558        if (len < processed) {
559            ND_PRINT(" [remaining length %u < %u]", len, processed);
560            nd_print_invalid(ndo);
561            break;
562        }
563        len -= processed;
564        pptr += processed;
565    }
566}
567
568static u_int
569ldp_pdu_print(netdissect_options *ndo,
570              const u_char *pptr)
571{
572    const struct ldp_common_header *ldp_com_header;
573    const struct ldp_msg_header *ldp_msg_header;
574    const u_char *tptr,*msg_tptr;
575    u_short tlen;
576    u_short pdu_len,msg_len,msg_type;
577    u_int msg_tlen;
578    int hexdump,processed;
579
580    ldp_com_header = (const struct ldp_common_header *)pptr;
581    ND_TCHECK_SIZE(ldp_com_header);
582
583    /*
584     * Sanity checking of the header.
585     */
586    if (GET_BE_U_2(ldp_com_header->version) != LDP_VERSION) {
587	ND_PRINT("%sLDP version %u packet not supported",
588               (ndo->ndo_vflag < 1) ? "" : "\n\t",
589               GET_BE_U_2(ldp_com_header->version));
590	return 0;
591    }
592
593    pdu_len = GET_BE_U_2(ldp_com_header->pdu_length);
594    if (pdu_len < sizeof(struct ldp_common_header)-4) {
595        /* length too short */
596        ND_PRINT("%sLDP, pdu-length: %u (too short, < %zu)",
597                 (ndo->ndo_vflag < 1) ? "" : "\n\t",
598                 pdu_len,
599                 sizeof(struct ldp_common_header)-4);
600        return 0;
601    }
602
603    /* print the LSR-ID, label-space & length */
604    ND_PRINT("%sLDP, Label-Space-ID: %s:%u, pdu-length: %u",
605           (ndo->ndo_vflag < 1) ? "" : "\n\t",
606           GET_IPADDR_STRING(ldp_com_header->lsr_id),
607           GET_BE_U_2(ldp_com_header->label_space),
608           pdu_len);
609
610    /* bail out if non-verbose */
611    if (ndo->ndo_vflag < 1)
612        return 0;
613
614    /* ok they seem to want to know everything - lets fully decode it */
615    tptr = pptr + sizeof(struct ldp_common_header);
616    tlen = pdu_len - (sizeof(struct ldp_common_header)-4);	/* Type & Length fields not included */
617
618    while(tlen>0) {
619        /* did we capture enough for fully decoding the msg header ? */
620        ND_TCHECK_LEN(tptr, sizeof(struct ldp_msg_header));
621
622        ldp_msg_header = (const struct ldp_msg_header *)tptr;
623        msg_len=GET_BE_U_2(ldp_msg_header->length);
624        msg_type=LDP_MASK_MSG_TYPE(GET_BE_U_2(ldp_msg_header->type));
625
626        if (msg_len < sizeof(struct ldp_msg_header)-4) {
627            /* length too short */
628            /* FIXME vendor private / experimental check */
629            ND_PRINT("\n\t  %s Message (0x%04x), length: %u (too short, < %zu)",
630                     tok2str(ldp_msg_values,
631                             "Unknown",
632                             msg_type),
633                     msg_type,
634                     msg_len,
635                     sizeof(struct ldp_msg_header)-4);
636            return 0;
637        }
638
639        /* FIXME vendor private / experimental check */
640        ND_PRINT("\n\t  %s Message (0x%04x), length: %u, Message ID: 0x%08x, Flags: [%s if unknown]",
641               tok2str(ldp_msg_values,
642                       "Unknown",
643                       msg_type),
644               msg_type,
645               msg_len,
646               GET_BE_U_4(ldp_msg_header->id),
647               LDP_MASK_U_BIT(GET_BE_U_2(ldp_msg_header->type)) ? "continue processing" : "ignore");
648
649        msg_tptr=tptr+sizeof(struct ldp_msg_header);
650        msg_tlen=msg_len-(sizeof(struct ldp_msg_header)-4); /* Type & Length fields not included */
651
652        /* did we capture enough for fully decoding the message ? */
653        ND_TCHECK_LEN(tptr, msg_len);
654        hexdump=FALSE;
655
656        switch(msg_type) {
657
658        case LDP_MSG_NOTIF:
659        case LDP_MSG_HELLO:
660        case LDP_MSG_INIT:
661        case LDP_MSG_KEEPALIVE:
662        case LDP_MSG_ADDRESS:
663        case LDP_MSG_LABEL_MAPPING:
664        case LDP_MSG_ADDRESS_WITHDRAW:
665        case LDP_MSG_LABEL_WITHDRAW:
666            while(msg_tlen >= 4) {
667                processed = ldp_tlv_print(ndo, msg_tptr, msg_tlen);
668                if (processed == 0)
669                    break;
670                msg_tlen-=processed;
671                msg_tptr+=processed;
672            }
673            break;
674
675        /*
676         *  FIXME those are the defined messages that lack a decoder
677         *  you are welcome to contribute code ;-)
678         */
679
680        case LDP_MSG_LABEL_REQUEST:
681        case LDP_MSG_LABEL_RELEASE:
682        case LDP_MSG_LABEL_ABORT_REQUEST:
683
684        default:
685            if (ndo->ndo_vflag <= 1)
686                print_unknown_data(ndo, msg_tptr, "\n\t  ", msg_tlen);
687            break;
688        }
689        /* do we want to see an additionally hexdump ? */
690        if (ndo->ndo_vflag > 1 || hexdump==TRUE)
691            print_unknown_data(ndo, tptr+sizeof(struct ldp_msg_header), "\n\t  ",
692                               msg_len);
693
694        tptr += msg_len+4;
695        tlen -= msg_len+4;
696    }
697    return pdu_len+4;
698trunc:
699    nd_trunc_longjmp(ndo);
700}
701