/*
* 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.
* 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.
*
* Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
*/

#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: print-otv.c,v 1.5 2024/09/02 16:15:32 christos Exp $");
#endif

/* \summary: Overlay Transport Virtualization (OTV) printer */

/* specification: draft-hasmit-otv-04 */

#include <config.h>

#include "netdissect-stdinc.h"

#define ND_LONGJMP_FROM_TCHECK
#include "netdissect.h"
#include "extract.h"

#define OTV_HDR_LEN 8

/*
* OTV header, draft-hasmit-otv-04
*
*     0                   1                   2                   3
*     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
*     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*     |R|R|R|R|I|R|R|R|           Overlay ID                          |
*     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*     |          Instance ID                          | Reserved      |
*     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
*/

void
otv_print(netdissect_options *ndo, const u_char *bp, u_int len)
{
   uint8_t flags;

   ndo->ndo_protocol = "otv";
   ND_PRINT("OTV, ");
   if (len < OTV_HDR_LEN) {
       ND_PRINT("[length %u < %u]", len, OTV_HDR_LEN);
       goto invalid;
   }

   flags = GET_U_1(bp);
   ND_PRINT("flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags);
   bp += 1;

   ND_PRINT("overlay %u, ", GET_BE_U_3(bp));
   bp += 3;

   ND_PRINT("instance %u\n", GET_BE_U_3(bp));
   bp += 3;

   /* Reserved */
   ND_TCHECK_1(bp);
   bp += 1;

   ether_print(ndo, bp, len - OTV_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
   return;

invalid:
   nd_print_invalid(ndo);
   ND_TCHECK_LEN(bp, len);
}