1 /* 2 * Copyright (c) 2001 William C. Fenner. 3 * 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 7 * distributions retain the above copyright notice and this paragraph 8 * in its entirety, and (2) distributions including binary code include 9 * the above copyright notice and this paragraph in its entirety in 10 * the documentation or other materials provided with the distribution. 11 * The name of William C. Fenner may not be used to endorse or 12 * promote products derived from this software without specific prior 13 * written permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND 14 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 15 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 16 * FOR A PARTICULAR PURPOSE. 17 */ 18 19 /* \summary: Multicast Source Discovery Protocol (MSDP) printer */ 20 21 #include <config.h> 22 23 #include "netdissect-stdinc.h" 24 25 #include "netdissect.h" 26 #include "addrtoname.h" 27 #include "extract.h" 28 29 #define MSDP_TYPE_MAX 7 30 31 void 32 msdp_print(netdissect_options *ndo, const u_char *sp, u_int length) 33 { 34 unsigned int type, len; 35 36 ndo->ndo_protocol = "msdp"; 37 ND_PRINT(": "); 38 nd_print_protocol(ndo); 39 /* See if we think we're at the beginning of a compound packet */ 40 type = GET_U_1(sp); 41 len = GET_BE_U_2(sp + 1); 42 if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX) 43 goto trunc; /* not really truncated, but still not decodable */ 44 while (length != 0) { 45 type = GET_U_1(sp); 46 len = GET_BE_U_2(sp + 1); 47 if (len > 1400 || ndo->ndo_vflag) 48 ND_PRINT(" [len %u]", len); 49 if (len < 3) 50 goto trunc; 51 if (length < len) 52 goto trunc; 53 sp += 3; 54 length -= 3; 55 switch (type) { 56 case 1: /* IPv4 Source-Active */ 57 case 3: /* IPv4 Source-Active Response */ 58 if (type == 1) 59 ND_PRINT(" SA"); 60 else 61 ND_PRINT(" SA-Response"); 62 ND_PRINT(" %u entries", GET_U_1(sp)); 63 if ((u_int)((GET_U_1(sp) * 12) + 8) < len) { 64 ND_PRINT(" [w/data]"); 65 if (ndo->ndo_vflag > 1) { 66 ND_PRINT(" "); 67 ip_print(ndo, sp + 68 GET_U_1(sp) * 12 + 8 - 3, 69 len - (GET_U_1(sp) * 12 + 8)); 70 } 71 } 72 break; 73 case 2: 74 ND_PRINT(" SA-Request"); 75 ND_PRINT(" for %s", GET_IPADDR_STRING(sp + 1)); 76 break; 77 case 4: 78 ND_PRINT(" Keepalive"); 79 if (len != 3) 80 ND_PRINT("[len=%u] ", len); 81 break; 82 case 5: 83 ND_PRINT(" Notification"); 84 break; 85 default: 86 ND_PRINT(" [type=%u len=%u]", type, len); 87 break; 88 } 89 sp += (len - 3); 90 length -= (len - 3); 91 } 92 return; 93 trunc: 94 nd_print_trunc(ndo); 95 } 96