xref: /netbsd-src/external/bsd/tcpdump/dist/print-otv.c (revision 26ba0b503b498a5194a71ac319838b7f5497f3fe)
1026d7285Schristos /*
2026d7285Schristos  * Redistribution and use in source and binary forms, with or without
3026d7285Schristos  * modification, are permitted provided that: (1) source code
4026d7285Schristos  * distributions retain the above copyright notice and this paragraph
5026d7285Schristos  * in its entirety, and (2) distributions including binary code include
6026d7285Schristos  * the above copyright notice and this paragraph in its entirety in
7026d7285Schristos  * the documentation or other materials provided with the distribution.
8026d7285Schristos  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
9026d7285Schristos  * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
10026d7285Schristos  * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
11026d7285Schristos  * FOR A PARTICULAR PURPOSE.
12026d7285Schristos  *
13026d7285Schristos  * Original code by Francesco Fondelli (francesco dot fondelli, gmail dot com)
14026d7285Schristos  */
15026d7285Schristos 
16fdccd7e4Schristos #include <sys/cdefs.h>
17fdccd7e4Schristos #ifndef lint
18*26ba0b50Schristos __RCSID("$NetBSD: print-otv.c,v 1.5 2024/09/02 16:15:32 christos Exp $");
19fdccd7e4Schristos #endif
20fdccd7e4Schristos 
21dc860a36Sspz /* \summary: Overlay Transport Virtualization (OTV) printer */
22dc860a36Sspz 
23dc860a36Sspz /* specification: draft-hasmit-otv-04 */
24dc860a36Sspz 
25c74ad251Schristos #include <config.h>
26026d7285Schristos 
27c74ad251Schristos #include "netdissect-stdinc.h"
28026d7285Schristos 
29c74ad251Schristos #define ND_LONGJMP_FROM_TCHECK
30784088dfSchristos #include "netdissect.h"
31026d7285Schristos #include "extract.h"
32026d7285Schristos 
33c74ad251Schristos #define OTV_HDR_LEN 8
34c74ad251Schristos 
35026d7285Schristos /*
36026d7285Schristos  * OTV header, draft-hasmit-otv-04
37026d7285Schristos  *
38026d7285Schristos  *     0                   1                   2                   3
39026d7285Schristos  *     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
40026d7285Schristos  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41026d7285Schristos  *     |R|R|R|R|I|R|R|R|           Overlay ID                          |
42026d7285Schristos  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
43026d7285Schristos  *     |          Instance ID                          | Reserved      |
44026d7285Schristos  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
45026d7285Schristos  */
46026d7285Schristos 
47026d7285Schristos void
48c47fd378Schristos otv_print(netdissect_options *ndo, const u_char *bp, u_int len)
49026d7285Schristos {
50c47fd378Schristos     uint8_t flags;
51026d7285Schristos 
52c74ad251Schristos     ndo->ndo_protocol = "otv";
53c74ad251Schristos     ND_PRINT("OTV, ");
54c74ad251Schristos     if (len < OTV_HDR_LEN) {
55c74ad251Schristos         ND_PRINT("[length %u < %u]", len, OTV_HDR_LEN);
56c74ad251Schristos         goto invalid;
57c74ad251Schristos     }
58026d7285Schristos 
59c74ad251Schristos     flags = GET_U_1(bp);
60c74ad251Schristos     ND_PRINT("flags [%s] (0x%02x), ", flags & 0x08 ? "I" : ".", flags);
61dc860a36Sspz     bp += 1;
62dc860a36Sspz 
63c74ad251Schristos     ND_PRINT("overlay %u, ", GET_BE_U_3(bp));
64dc860a36Sspz     bp += 3;
65dc860a36Sspz 
66c74ad251Schristos     ND_PRINT("instance %u\n", GET_BE_U_3(bp));
67dc860a36Sspz     bp += 3;
68dc860a36Sspz 
69dc860a36Sspz     /* Reserved */
70c74ad251Schristos     ND_TCHECK_1(bp);
71dc860a36Sspz     bp += 1;
72dc860a36Sspz 
73c74ad251Schristos     ether_print(ndo, bp, len - OTV_HDR_LEN, ND_BYTES_AVAILABLE_AFTER(bp), NULL, NULL);
74dc860a36Sspz     return;
75dc860a36Sspz 
76c74ad251Schristos invalid:
77c74ad251Schristos     nd_print_invalid(ndo);
78c74ad251Schristos     ND_TCHECK_LEN(bp, len);
79026d7285Schristos }
80