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 1.5 2024/09/02 16:15:32 christos Exp $"); 19 #endif 20 21 /* \summary: Overlay Transport Virtualization (OTV) printer */ 22 23 /* specification: draft-hasmit-otv-04 */ 24 25 #include <config.h> 26 27 #include "netdissect-stdinc.h" 28 29 #define ND_LONGJMP_FROM_TCHECK 30 #include "netdissect.h" 31 #include "extract.h" 32 33 #define OTV_HDR_LEN 8 34 35 /* 36 * OTV header, draft-hasmit-otv-04 37 * 38 * 0 1 2 3 39 * 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 40 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 41 * |R|R|R|R|I|R|R|R| Overlay ID | 42 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 43 * | Instance ID | Reserved | 44 * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 45 */ 46 47 void 48 otv_print(netdissect_options *ndo, const u_char *bp, u_int len) 49 { 50 uint8_t flags; 51 52 ndo->ndo_protocol = "otv"; 53 ND_PRINT("OTV, "); 54 if (len < OTV_HDR_LEN) { 55 ND_PRINT("[length %u < %u]", len, OTV_HDR_LEN); 56 goto invalid; 57 } 58 59 flags = GET_U_1(bp); 60 ND_PRINT("flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags); 61 bp += 1; 62 63 ND_PRINT("overlay %u, ", GET_BE_U_3(bp)); 64 bp += 3; 65 66 ND_PRINT("instance %u\n", GET_BE_U_3(bp)); 67 bp += 3; 68 69 /* Reserved */ 70 ND_TCHECK_1(bp); 71 bp += 1; 72 73 ether_print(ndo, bp, len - OTV_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL); 74 return; 75 76 invalid: 77 nd_print_invalid(ndo); 78 ND_TCHECK_LEN(bp, len); 79 } 80