| /* $OpenBSD: print-carp.c,v 1.6 2009/10/27 23:59:55 deraadt Exp $ */ |
| |
| /* |
| * Copyright (c) 2000 William C. Fenner. |
| * All rights reserved. |
| * |
| * Kevin Steves <[email protected]> July 2000 |
| * Modified to: |
| * - print version, type string and packet length |
| * - print IP address count if > 1 (-v) |
| * - verify checksum (-v) |
| * - print authentication string (-v) |
| * |
| * Copyright (c) 2011 Advanced Computing Technologies |
| * George V. Neille-Neil |
| * |
| * Modified to: |
| * - work correctly with CARP |
| * - compile into the latest tcpdump |
| * - print out the counter |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that: (1) source code |
| * distributions retain the above copyright notice and this paragraph |
| * in its entirety, and (2) distributions including binary code include |
| * the above copyright notice and this paragraph in its entirety in |
| * the documentation or other materials provided with the distribution. |
| * The name of William C. Fenner may not be used to endorse or |
| * promote products derived from this software without specific prior |
| * written permission. THIS SOFTWARE IS PROVIDED ``AS IS'' AND |
| * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT |
| * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE. |
| * |
| */ |
| |
| /* \summary: Common Address Redundancy Protocol (CARP) printer */ |
| |
| #ifdef HAVE_CONFIG_H |
| #include <config.h> |
| #endif |
| |
| #include "netdissect-stdinc.h" |
| |
| #include "netdissect.h" /* for checksum structure and functions */ |
| #include "extract.h" |
| |
| void |
| carp_print(netdissect_options *ndo, const u_char *bp, u_int len, u_int ttl) |
| { |
| u_int version, type; |
| const char *type_s; |
| |
| ndo->ndo_protocol = "carp"; |
| ND_TCHECK_1(bp); |
| version = (EXTRACT_U_1(bp) & 0xf0) >> 4; |
| type = EXTRACT_U_1(bp) & 0x0f; |
| if (type == 1) |
| type_s = "advertise"; |
| else |
| type_s = "unknown"; |
| ND_PRINT("CARPv%u-%s %u: ", version, type_s, len); |
| if (ttl != 255) |
| ND_PRINT("[ttl=%u!] ", ttl); |
| if (version != 2 || type != 1) |
| return; |
| ND_TCHECK_1(bp + 2); |
| ND_TCHECK_1(bp + 5); |
| ND_PRINT("vhid=%u advbase=%u advskew=%u authlen=%u ", |
| EXTRACT_U_1(bp + 1), EXTRACT_U_1(bp + 5), EXTRACT_U_1(bp + 2), EXTRACT_U_1(bp + 3)); |
| if (ndo->ndo_vflag) { |
| struct cksum_vec vec[1]; |
| vec[0].ptr = (const uint8_t *)bp; |
| vec[0].len = len; |
| if (ND_TTEST_LEN(bp, len) && in_cksum(vec, 1)) |
| ND_PRINT(" (bad carp cksum %x!)", |
| EXTRACT_BE_U_2(bp + 6)); |
| } |
| ND_PRINT("counter=%" PRIu64, EXTRACT_BE_U_8(bp + 8)); |
| |
| return; |
| trunc: |
| nd_print_trunc(ndo); |
| } |
