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 #ifdef HAVE_CONFIG_H 22 #include "config.h" 23 #endif 24 25 #include <netdissect-stdinc.h> 26 27 #include "netdissect.h" 28 #include "addrtoname.h" 29 #include "extract.h" 30 31 #define MSDP_TYPE_MAX 7 32 33 void 34 msdp_print(netdissect_options *ndo, const u_char *sp, u_int length) 35 { 36 unsigned int type, len; 37 38 ND_TCHECK2(*sp, 3); 39 /* See if we think we're at the beginning of a compound packet */ 40 type = *sp; 41 len = EXTRACT_16BITS(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 ND_PRINT((ndo, " msdp:")); 45 while (length > 0) { 46 ND_TCHECK2(*sp, 3); 47 type = *sp; 48 len = EXTRACT_16BITS(sp + 1); 49 if (len > 1400 || ndo->ndo_vflag) 50 ND_PRINT((ndo, " [len %u]", len)); 51 if (len < 3) 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((ndo, " SA")); 60 else 61 ND_PRINT((ndo, " SA-Response")); 62 ND_TCHECK(*sp); 63 ND_PRINT((ndo, " %u entries", *sp)); 64 if ((u_int)((*sp * 12) + 8) < len) { 65 ND_PRINT((ndo, " [w/data]")); 66 if (ndo->ndo_vflag > 1) { 67 ND_PRINT((ndo, " ")); 68 ip_print(ndo, sp + *sp * 12 + 8 - 3, 69 len - (*sp * 12 + 8)); 70 } 71 } 72 break; 73 case 2: 74 ND_PRINT((ndo, " SA-Request")); 75 ND_TCHECK2(*sp, 5); 76 ND_PRINT((ndo, " for %s", ipaddr_string(ndo, sp + 1))); 77 break; 78 case 4: 79 ND_PRINT((ndo, " Keepalive")); 80 if (len != 3) 81 ND_PRINT((ndo, "[len=%d] ", len)); 82 break; 83 case 5: 84 ND_PRINT((ndo, " Notification")); 85 break; 86 default: 87 ND_PRINT((ndo, " [type=%d len=%d]", type, len)); 88 break; 89 } 90 sp += (len - 3); 91 length -= (len - 3); 92 } 93 return; 94 trunc: 95 ND_PRINT((ndo, " [|msdp]")); 96 } 97 98 /* 99 * Local Variables: 100 * c-style: whitesmith 101 * c-basic-offset: 8 102 * End: 103 */ 104
