Home | History | Annotate | Download | only in tcpdump
      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 (at) juniper.net)
     14  *  and Steinar Haug (sthaug (at) 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