usr/src/cmd/cmd-inet/usr.sbin/snoop/snoop_igmp.c

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26
  27 #pragma ident   "%Z%%M% %I%     %E% SMI"
  28
  29 #include <stdio.h>
  30 #include <string.h>
  31 #include <sys/types.h>
  32 #include <sys/socket.h>
  33 #include <net/if.h>
  34 #include <sys/stropts.h>
  35 #include <sys/sysmacros.h>
  36 #include <netinet/in_systm.h>
  37 #include <netinet/in.h>
  38 #include <netinet/ip.h>
  39 #include <netinet/igmp.h>
  40 #include <inet/ip.h>
  41 #include <arpa/inet.h>
  42 #include <netdb.h>
  43 #include "snoop.h"
  44
  45 static void interpret_igmpv3qry(struct igmp *, int);
  46 static void interpret_igmpv3rpt(struct igmp *, int);
  47
  48
  49 /*ARGSUSED*/
  50 void
  51 interpret_igmp(int flags, char *data, int iplen, int ilen)
  52 {
  53         const char *pt;
  54         char *line;
  55         struct igmp *igmp = (struct igmp *)data;
  56         char addrstr[INET_ADDRSTRLEN];
  57
  58         if (ilen < IGMP_MINLEN) {
  59                 /* incomplete header */
  60                 line = get_sum_line();
  61                 (void) snprintf(line, MAXLINE, "Malformed IGMP packet");
  62                 return;
  63         }
  64
  65         switch (igmp->igmp_type) {
  66         case IGMP_MEMBERSHIP_QUERY:
  67                 if (ilen == IGMP_MINLEN) {
  68                         if (igmp->igmp_code == 0)
  69                                 pt = "v1 membership query";
  70                         else
  71                                 pt = "v2 membership query";
  72                 } else if (ilen >= IGMP_V3_QUERY_MINLEN) {
  73                         pt = "v3 membership query";
  74                 } else {
  75                         pt = "Unknown membership query";
  76                 }
  77                 break;
  78         case IGMP_V1_MEMBERSHIP_REPORT:
  79                 pt = "v1 membership report";
  80                 break;
  81         case IGMP_V2_MEMBERSHIP_REPORT:
  82                 pt = "v2 membership report";
  83                 break;
  84         case IGMP_V3_MEMBERSHIP_REPORT:
  85                 pt = "v3 membership report";
  86                 break;
  87         case IGMP_V2_LEAVE_GROUP:
  88                 pt = "v2 leave group";
  89                 break;
  90
  91         default:
  92                 pt = "Unknown";
  93                 break;
  94         }
  95
  96         if (flags & F_SUM) {
  97                 line = get_sum_line();
  98                 (void) snprintf(line, MAXLINE, "IGMP %s", pt);
  99         }
 100
 101         if (flags & F_DTAIL) {
 102                 show_header("IGMP:  ", "IGMP Header", ilen);
 103                 show_space();
 104                 (void) snprintf(get_line(0, 0), get_line_remain(),
 105                     "Type = %d (%s)", igmp->igmp_type, pt);
 106                 (void) snprintf(get_line(0, 0), get_line_remain(),
 107                     "Max Response Time = %d", igmp->igmp_code);
 108                 (void) snprintf(get_line(0, 0), get_line_remain(),
 109                     "Checksum = %x", ntohs(igmp->igmp_cksum));
 110
 111                 if (igmp->igmp_type == IGMP_MEMBERSHIP_QUERY &&
 112                     ilen >= IGMP_V3_QUERY_MINLEN) {
 113                         interpret_igmpv3qry(igmp, ilen);
 114                 } else if (igmp->igmp_type == IGMP_V3_MEMBERSHIP_REPORT) {
 115                         interpret_igmpv3rpt(igmp, ilen);
 116                 } else {
 117                         (void) snprintf(get_line(0, 0), get_line_remain(),
 118                             "Group = %s",
 119                             inet_ntop(AF_INET, &igmp->igmp_group.s_addr,
 120                             addrstr, INET_ADDRSTRLEN));
 121                 }
 122
 123                 show_space();
 124         }
 125 }
 126
 127 static void
 128 interpret_igmpv3qry(struct igmp *igmp, int ilen)
 129 {
 130         struct igmp3q *qry;
 131         struct in_addr *src;
 132         int rem = ilen;
 133         int srccnt;
 134         char addrstr[INET_ADDRSTRLEN];
 135
 136         if (ilen < sizeof (*qry)) {
 137                 (void) snprintf(get_line(0, 0), get_line_remain(),
 138                     "Malformed IGMP Query");
 139                 return;
 140         }
 141
 142         qry = (struct igmp3q *)igmp;
 143         rem -= sizeof (*qry);
 144         srccnt = ntohs(qry->igmp3q_numsrc);
 145         (void) snprintf(get_line(0, 0), get_line_remain(),
 146             "Group = %s", inet_ntop(AF_INET, &qry->igmp3q_group, addrstr,
 147             INET_ADDRSTRLEN));
 148         (void) snprintf(get_line(0, 0), get_line_remain(),
 149             "%d Source Address%s:", srccnt, (srccnt == 1) ? "" : "es");
 150
 151         src = (struct in_addr *)&qry[1];
 152         while (srccnt > 0 && rem >= sizeof (*src)) {
 153                 rem -= sizeof (*src);
 154
 155                 (void) snprintf(get_line(0, 0), get_line_remain(), "    %s",
 156                     inet_ntop(AF_INET, &src->s_addr, addrstr, INET_ADDRSTRLEN));
 157
 158                 srccnt--;
 159                 src++;
 160         }
 161 }
 162
 163 #define MAX_IGMPV3_REPORT_TYPE  6
 164
 165 const char *igmpv3rpt_types[] = {
 166         "<unknown>",
 167         "MODE_IS_INCLUDE",
 168         "MODE_IS_EXCLUDE",
 169         "CHANGE_TO_INCLUDE",
 170         "CHANGE_TO_EXCLUDE",
 171         "ALLOW_NEW_SOURCES",
 172         "BLOCK_OLD_SOURCES",
 173 };
 174
 175 static void
 176 interpret_igmpv3rpt(struct igmp *igmp, int ilen)
 177 {
 178         struct igmp3r *rpt;
 179         struct grphdr *grh;
 180         struct in_addr *src;
 181         int rem = ilen, auxlen;
 182         uint16_t grhcnt, srccnt;
 183         char addrstr[INET_ADDRSTRLEN];
 184
 185         if (ilen < sizeof (*rpt)) {
 186                 (void) snprintf(get_line(0, 0), get_line_remain(),
 187                     "Malformed IGMPv3 Report");
 188                 return;
 189         }
 190
 191         rpt = (struct igmp3r *)igmp;
 192         grh = (struct grphdr *)&rpt[1];
 193         grhcnt = ntohs(rpt->igmp3r_numrec);
 194         (void) snprintf(get_line(0, 0), get_line_remain(),
 195             "%d Group Record%s:", grhcnt, (grhcnt == 1) ? "" : "s");
 196         rem -= sizeof (*rpt);
 197         while (grhcnt > 0 && rem >= sizeof (*grh)) {
 198                 rem -= sizeof (*grh);
 199
 200                 (void) snprintf(get_line(0, 0), get_line_remain(),
 201                     "Group = %s  type = %s", inet_ntop(AF_INET,
 202                     &grh->grphdr_group.s_addr, addrstr, INET_ADDRSTRLEN),
 203                     (grh->grphdr_type > MAX_IGMPV3_REPORT_TYPE) ?
 204                     "<unknown>" : igmpv3rpt_types[grh->grphdr_type]);
 205                 srccnt = ntohs(grh->grphdr_numsrc);
 206                 (void) snprintf(get_line(0, 0), get_line_remain(),
 207                     "%d Source Address%s:", srccnt, (srccnt == 1) ? "" : "es");
 208
 209                 src = (struct in_addr *)&grh[1];
 210                 while (srccnt > 0 && rem >= sizeof (*src)) {
 211                         rem -= sizeof (*src);
 212
 213                         (void) snprintf(get_line(0, 0), get_line_remain(),
 214                             "    %s", inet_ntop(AF_INET, &src->s_addr, addrstr,
 215                             INET_ADDRSTRLEN));
 216
 217                         srccnt--;
 218                         src++;
 219                 }
 220
 221                 grhcnt--;
 222                 auxlen = grh->grphdr_auxlen * 4;
 223                 rem -= auxlen;
 224                 grh = (struct grphdr *)((uint8_t *)src + auxlen);
 225         }
 226 }