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 #include <sys/cdefs.h> 20 #ifndef lint 21 __RCSID("$NetBSD: print-msdp.c,v 1.8 2024/09/02 16:15:32 christos Exp $"); 22 #endif 23 24 /* \summary: Multicast Source Discovery Protocol (MSDP) printer */ 25 26 #include <config.h> 27 28 #include "netdissect-stdinc.h" 29 30 #include "netdissect.h" 31 #include "addrtoname.h" 32 #include "extract.h" 33 34 #define MSDP_TYPE_MAX 7 35 36 void 37 msdp_print(netdissect_options *ndo, const u_char *sp, u_int length) 38 { 39 unsigned int type, len; 40 41 ndo->ndo_protocol = "msdp"; 42 ND_PRINT(": "); 43 nd_print_protocol(ndo); 44 /* See if we think we're at the beginning of a compound packet */ 45 type = GET_U_1(sp); 46 len = GET_BE_U_2(sp + 1); 47 if (len > 1500 || len < 3 || type == 0 || type > MSDP_TYPE_MAX) 48 goto trunc; /* not really truncated, but still not decodable */ 49 while (length != 0) { 50 type = GET_U_1(sp); 51 len = GET_BE_U_2(sp + 1); 52 if (len > 1400 || ndo->ndo_vflag) 53 ND_PRINT(" [len %u]", len); 54 if (len < 3) 55 goto trunc; 56 if (length < len) 57 goto trunc; 58 sp += 3; 59 length -= 3; 60 switch (type) { 61 case 1: /* IPv4 Source-Active */ 62 case 3: /* IPv4 Source-Active Response */ 63 if (type == 1) 64 ND_PRINT(" SA"); 65 else 66 ND_PRINT(" SA-Response"); 67 ND_PRINT(" %u entries", GET_U_1(sp)); 68 if ((u_int)((GET_U_1(sp) * 12) + 8) < len) { 69 ND_PRINT(" [w/data]"); 70 if (ndo->ndo_vflag > 1) { 71 ND_PRINT(" "); 72 ip_print(ndo, sp + 73 GET_U_1(sp) * 12 + 8 - 3, 74 len - (GET_U_1(sp) * 12 + 8)); 75 } 76 } 77 break; 78 case 2: 79 ND_PRINT(" SA-Request"); 80 ND_PRINT(" for %s", GET_IPADDR_STRING(sp + 1)); 81 break; 82 case 4: 83 ND_PRINT(" Keepalive"); 84 if (len != 3) 85 ND_PRINT("[len=%u] ", len); 86 break; 87 case 5: 88 ND_PRINT(" Notification"); 89 break; 90 default: 91 ND_PRINT(" [type=%u len=%u]", type, len); 92 break; 93 } 94 sp += (len - 3); 95 length -= (len - 3); 96 } 97 return; 98 trunc: 99 nd_print_trunc(ndo); 100 } 101