1 /* 2 * Redistribution and use in source and binary forms, with or without 3 * modification, are permitted provided that: (1) source code 4 * distributions retain the above copyright notice and this paragraph 5 * in its entirety, and (2) distributions including binary code include 6 * the above copyright notice and this paragraph in its entirety in 7 * the documentation or other materials provided with the distribution. 8 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND 9 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT 10 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 11 * FOR A PARTICULAR PURPOSE. 12 * 13 * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com) 14 */ 15 16 #include <sys/cdefs.h> 17 #ifndef lint 18 __RCSID("$NetBSD: print-otv.c,v 1.4 2023/08/17 20:19:40 christos Exp $"); 19 #endif 20 21 /* \summary: Overlay Transport Virtualization (OTV) printer */ 22 23 /* specification: draft-hasmit-otv-04 */ 24 25 #ifdef HAVE_CONFIG_H 26 #include <config.h> 27 #endif 28 29 #include "netdissect-stdinc.h" 30 31 #define ND_LONGJMP_FROM_TCHECK 32 #include "netdissect.h" 33 #include "extract.h" 34 35 #define OTV_HDR_LEN 8 36 37 /* 38 * OTV header, draft-hasmit-otv-04 39 * 40 * 0 1 2 3 41 * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 42 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 43 * |R|R|R|R|I|R|R|R| Overlay ID | 44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 45 * | Instance ID | Reserved | 46 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 47 */ 48 49 void 50 otv_print(netdissect_options *ndo, const u_char *bp, u_int len) 51 { 52 uint8_t flags; 53 54 ndo->ndo_protocol = "otv"; 55 ND_PRINT("OTV, "); 56 if (len < OTV_HDR_LEN) { 57 ND_PRINT("[length %u < %u]", len, OTV_HDR_LEN); 58 goto invalid; 59 } 60 61 flags = GET_U_1(bp); 62 ND_PRINT("flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags); 63 bp += 1; 64 65 ND_PRINT("overlay %u, ", GET_BE_U_3(bp)); 66 bp += 3; 67 68 ND_PRINT("instance %u\n", GET_BE_U_3(bp)); 69 bp += 3; 70 71 /* Reserved */ 72 ND_TCHECK_1(bp); 73 bp += 1; 74 75 ether_print(ndo, bp, len - OTV_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL); 76 return; 77 78 invalid: 79 nd_print_invalid(ndo); 80 ND_TCHECK_LEN(bp, len); 81 } 82