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      1 /*
      2  * Copyright (c) 1988, 1989, 1990, 1991, 1993, 1994, 1995, 1996
      3  *  The Regents of the University of California.  All rights reserved.
      4  *
      5  * Redistribution and use in source and binary forms, with or without
      6  * modification, are permitted provided that: (1) source code distributions
      7  * retain the above copyright notice and this paragraph in its entirety, (2)
      8  * distributions including binary code include the above copyright notice and
      9  * this paragraph in its entirety in the documentation or other materials
     10  * provided with the distribution, and (3) all advertising materials mentioning
     11  * features or use of this software display the following acknowledgement:
     12  * ``This product includes software developed by the University of California,
     13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
     14  * the University nor the names of its contributors may be used to endorse
     15  * or promote products derived from this software without specific prior
     16  * written permission.
     17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
     18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
     19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
     20  */
     21 
     22 /* \summary: Internet Group Management Protocol (IGMP) 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 "addrtoname.h"
     32 #include "extract.h"
     33 
     34 #ifndef IN_CLASSD
     35 #define IN_CLASSD(i) (((int32_t)(i) & 0xf0000000) == 0xe0000000)
     36 #endif
     37 
     38 static const char tstr[] = "[|igmp]";
     39 
     40 /* (following from ipmulti/mrouted/prune.h) */
     41 
     42 /*
     43  * The packet format for a traceroute request.
     44  */
     45 struct tr_query {
     46     uint32_t  tr_src;          /* traceroute source */
     47     uint32_t  tr_dst;          /* traceroute destination */
     48     uint32_t  tr_raddr;        /* traceroute response address */
     49     uint32_t  tr_rttlqid;      /* response ttl and qid */
     50 };
     51 
     52 #define TR_GETTTL(x)        (int)(((x) >> 24) & 0xff)
     53 #define TR_GETQID(x)        ((x) & 0x00ffffff)
     54 
     55 /*
     56  * Traceroute response format.  A traceroute response has a tr_query at the
     57  * beginning, followed by one tr_resp for each hop taken.
     58  */
     59 struct tr_resp {
     60     uint32_t tr_qarr;          /* query arrival time */
     61     uint32_t tr_inaddr;        /* incoming interface address */
     62     uint32_t tr_outaddr;       /* outgoing interface address */
     63     uint32_t tr_rmtaddr;       /* parent address in source tree */
     64     uint32_t tr_vifin;         /* input packet count on interface */
     65     uint32_t tr_vifout;        /* output packet count on interface */
     66     uint32_t tr_pktcnt;        /* total incoming packets for src-grp */
     67     uint8_t  tr_rproto;      /* routing proto deployed on router */
     68     uint8_t  tr_fttl;        /* ttl required to forward on outvif */
     69     uint8_t  tr_smask;       /* subnet mask for src addr */
     70     uint8_t  tr_rflags;      /* forwarding error codes */
     71 };
     72 
     73 /* defs within mtrace */
     74 #define TR_QUERY 1
     75 #define TR_RESP 2
     76 
     77 /* fields for tr_rflags (forwarding error codes) */
     78 #define TR_NO_ERR   0
     79 #define TR_WRONG_IF 1
     80 #define TR_PRUNED   2
     81 #define TR_OPRUNED  3
     82 #define TR_SCOPED   4
     83 #define TR_NO_RTE   5
     84 #define TR_NO_FWD   7
     85 #define TR_NO_SPACE 0x81
     86 #define TR_OLD_ROUTER   0x82
     87 
     88 /* fields for tr_rproto (routing protocol) */
     89 #define TR_PROTO_DVMRP  1
     90 #define TR_PROTO_MOSPF  2
     91 #define TR_PROTO_PIM    3
     92 #define TR_PROTO_CBT    4
     93 
     94 /* igmpv3 report types */
     95 static const struct tok igmpv3report2str[] = {
     96 	{ 1,	"is_in" },
     97 	{ 2,	"is_ex" },
     98 	{ 3,	"to_in" },
     99 	{ 4,	"to_ex" },
    100 	{ 5,	"allow" },
    101 	{ 6,	"block" },
    102 	{ 0,	NULL }
    103 };
    104 
    105 static void
    106 print_mtrace(netdissect_options *ndo,
    107              register const u_char *bp, register u_int len)
    108 {
    109     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
    110 
    111     ND_TCHECK(*tr);
    112     if (len < 8 + sizeof (struct tr_query)) {
    113 	ND_PRINT((ndo, " [invalid len %d]", len));
    114 	return;
    115     }
    116     ND_PRINT((ndo, "mtrace %u: %s to %s reply-to %s",
    117         TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
    118         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
    119         ipaddr_string(ndo, &tr->tr_raddr)));
    120     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
    121         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
    122     return;
    123 trunc:
    124     ND_PRINT((ndo, "%s", tstr));
    125 }
    126 
    127 static void
    128 print_mresp(netdissect_options *ndo,
    129             register const u_char *bp, register u_int len)
    130 {
    131     register const struct tr_query *tr = (const struct tr_query *)(bp + 8);
    132 
    133     ND_TCHECK(*tr);
    134     if (len < 8 + sizeof (struct tr_query)) {
    135 	ND_PRINT((ndo, " [invalid len %d]", len));
    136 	return;
    137     }
    138     ND_PRINT((ndo, "mresp %lu: %s to %s reply-to %s",
    139         (u_long)TR_GETQID(EXTRACT_32BITS(&tr->tr_rttlqid)),
    140         ipaddr_string(ndo, &tr->tr_src), ipaddr_string(ndo, &tr->tr_dst),
    141         ipaddr_string(ndo, &tr->tr_raddr)));
    142     if (IN_CLASSD(EXTRACT_32BITS(&tr->tr_raddr)))
    143         ND_PRINT((ndo, " with-ttl %d", TR_GETTTL(EXTRACT_32BITS(&tr->tr_rttlqid))));
    144     return;
    145 trunc:
    146     ND_PRINT((ndo, "%s", tstr));
    147 }
    148 
    149 static void
    150 print_igmpv3_report(netdissect_options *ndo,
    151                     register const u_char *bp, register u_int len)
    152 {
    153     u_int group, nsrcs, ngroups;
    154     register u_int i, j;
    155 
    156     /* Minimum len is 16, and should be a multiple of 4 */
    157     if (len < 16 || len & 0x03) {
    158 	ND_PRINT((ndo, " [invalid len %d]", len));
    159 	return;
    160     }
    161     ND_TCHECK2(bp[6], 2);
    162     ngroups = EXTRACT_16BITS(&bp[6]);
    163     ND_PRINT((ndo, ", %d group record(s)", ngroups));
    164     if (ndo->ndo_vflag > 0) {
    165 	/* Print the group records */
    166 	group = 8;
    167         for (i=0; i<ngroups; i++) {
    168 	    if (len < group+8) {
    169 		ND_PRINT((ndo, " [invalid number of groups]"));
    170 		return;
    171 	    }
    172 	    ND_TCHECK2(bp[group+4], 4);
    173             ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[group+4])));
    174 	    ND_PRINT((ndo, " %s", tok2str(igmpv3report2str, " [v3-report-#%d]",
    175 								bp[group])));
    176             nsrcs = EXTRACT_16BITS(&bp[group+2]);
    177 	    /* Check the number of sources and print them */
    178 	    if (len < group+8+(nsrcs<<2)) {
    179 		ND_PRINT((ndo, " [invalid number of sources %d]", nsrcs));
    180 		return;
    181 	    }
    182             if (ndo->ndo_vflag == 1)
    183                 ND_PRINT((ndo, ", %d source(s)", nsrcs));
    184             else {
    185 		/* Print the sources */
    186                 ND_PRINT((ndo, " {"));
    187                 for (j=0; j<nsrcs; j++) {
    188 		    ND_TCHECK2(bp[group+8+(j<<2)], 4);
    189 		    ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[group+8+(j<<2)])));
    190 		}
    191                 ND_PRINT((ndo, " }"));
    192             }
    193 	    /* Next group record */
    194             group += 8 + (nsrcs << 2);
    195 	    ND_PRINT((ndo, "]"));
    196         }
    197     }
    198     return;
    199 trunc:
    200     ND_PRINT((ndo, "%s", tstr));
    201 }
    202 
    203 static void
    204 print_igmpv3_query(netdissect_options *ndo,
    205                    register const u_char *bp, register u_int len)
    206 {
    207     u_int mrc;
    208     u_int mrt;
    209     u_int nsrcs;
    210     register u_int i;
    211 
    212     ND_PRINT((ndo, " v3"));
    213     /* Minimum len is 12, and should be a multiple of 4 */
    214     if (len < 12 || len & 0x03) {
    215 	ND_PRINT((ndo, " [invalid len %d]", len));
    216 	return;
    217     }
    218     ND_TCHECK(bp[1]);
    219     mrc = bp[1];
    220     if (mrc < 128) {
    221 	mrt = mrc;
    222     } else {
    223         mrt = ((mrc & 0x0f) | 0x10) << (((mrc & 0x70) >> 4) + 3);
    224     }
    225     if (mrc != 100) {
    226 	ND_PRINT((ndo, " [max resp time "));
    227         if (mrt < 600) {
    228             ND_PRINT((ndo, "%.1fs", mrt * 0.1));
    229         } else {
    230             unsigned_relts_print(ndo, mrt / 10);
    231         }
    232 	ND_PRINT((ndo, "]"));
    233     }
    234     ND_TCHECK2(bp[4], 4);
    235     if (EXTRACT_32BITS(&bp[4]) == 0)
    236 	return;
    237     ND_PRINT((ndo, " [gaddr %s", ipaddr_string(ndo, &bp[4])));
    238     ND_TCHECK2(bp[10], 2);
    239     nsrcs = EXTRACT_16BITS(&bp[10]);
    240     if (nsrcs > 0) {
    241 	if (len < 12 + (nsrcs << 2))
    242 	    ND_PRINT((ndo, " [invalid number of sources]"));
    243 	else if (ndo->ndo_vflag > 1) {
    244 	    ND_PRINT((ndo, " {"));
    245 	    for (i=0; i<nsrcs; i++) {
    246 		ND_TCHECK2(bp[12+(i<<2)], 4);
    247 		ND_PRINT((ndo, " %s", ipaddr_string(ndo, &bp[12+(i<<2)])));
    248 	    }
    249 	    ND_PRINT((ndo, " }"));
    250 	} else
    251 	    ND_PRINT((ndo, ", %d source(s)", nsrcs));
    252     }
    253     ND_PRINT((ndo, "]"));
    254     return;
    255 trunc:
    256     ND_PRINT((ndo, "%s", tstr));
    257 }
    258 
    259 void
    260 igmp_print(netdissect_options *ndo,
    261            register const u_char *bp, register u_int len)
    262 {
    263     struct cksum_vec vec[1];
    264 
    265     if (ndo->ndo_qflag) {
    266         ND_PRINT((ndo, "igmp"));
    267         return;
    268     }
    269 
    270     ND_TCHECK(bp[0]);
    271     switch (bp[0]) {
    272     case 0x11:
    273         ND_PRINT((ndo, "igmp query"));
    274 	if (len >= 12)
    275 	    print_igmpv3_query(ndo, bp, len);
    276 	else {
    277             ND_TCHECK(bp[1]);
    278 	    if (bp[1]) {
    279 		ND_PRINT((ndo, " v2"));
    280 		if (bp[1] != 100)
    281 		    ND_PRINT((ndo, " [max resp time %d]", bp[1]));
    282 	    } else
    283 		ND_PRINT((ndo, " v1"));
    284             ND_TCHECK2(bp[4], 4);
    285 	    if (EXTRACT_32BITS(&bp[4]))
    286                 ND_PRINT((ndo, " [gaddr %s]", ipaddr_string(ndo, &bp[4])));
    287             if (len != 8)
    288                 ND_PRINT((ndo, " [len %d]", len));
    289 	}
    290         break;
    291     case 0x12:
    292         ND_TCHECK2(bp[4], 4);
    293         ND_PRINT((ndo, "igmp v1 report %s", ipaddr_string(ndo, &bp[4])));
    294         if (len != 8)
    295             ND_PRINT((ndo, " [len %d]", len));
    296         break;
    297     case 0x16:
    298         ND_TCHECK2(bp[4], 4);
    299         ND_PRINT((ndo, "igmp v2 report %s", ipaddr_string(ndo, &bp[4])));
    300         break;
    301     case 0x22:
    302         ND_PRINT((ndo, "igmp v3 report"));
    303 	print_igmpv3_report(ndo, bp, len);
    304         break;
    305     case 0x17:
    306         ND_TCHECK2(bp[4], 4);
    307         ND_PRINT((ndo, "igmp leave %s", ipaddr_string(ndo, &bp[4])));
    308         break;
    309     case 0x13:
    310         ND_PRINT((ndo, "igmp dvmrp"));
    311         if (len < 8)
    312             ND_PRINT((ndo, " [len %d]", len));
    313         else
    314             dvmrp_print(ndo, bp, len);
    315         break;
    316     case 0x14:
    317         ND_PRINT((ndo, "igmp pimv1"));
    318         pimv1_print(ndo, bp, len);
    319         break;
    320     case 0x1e:
    321         print_mresp(ndo, bp, len);
    322         break;
    323     case 0x1f:
    324         print_mtrace(ndo, bp, len);
    325         break;
    326     default:
    327         ND_PRINT((ndo, "igmp-%d", bp[0]));
    328         break;
    329     }
    330 
    331     if (ndo->ndo_vflag && len >= 4 && ND_TTEST2(bp[0], len)) {
    332         /* Check the IGMP checksum */
    333         vec[0].ptr = bp;
    334         vec[0].len = len;
    335         if (in_cksum(vec, 1))
    336             ND_PRINT((ndo, " bad igmp cksum %x!", EXTRACT_16BITS(&bp[2])));
    337     }
    338     return;
    339 trunc:
    340     ND_PRINT((ndo, "%s", tstr));
    341 }
    342