xref: /freebsd/contrib/tcpdump/print-otv.c (revision 8d20be1e22095c27faf8fe8b2f0d089739cc742e)
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 #ifdef HAVE_CONFIG_H
17 #include "config.h"
18 #endif
19 
20 #include <tcpdump-stdinc.h>
21 
22 #include <stdio.h>
23 #include <stdlib.h>
24 
25 #include "interface.h"
26 #include "extract.h"
27 #include "addrtoname.h"
28 
29 #include "udp.h"
30 
31 /*
32  * OTV header, draft-hasmit-otv-04
33  *
34  *     0                   1                   2                   3
35  *     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
36  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
37  *     |R|R|R|R|I|R|R|R|           Overlay ID                          |
38  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
39  *     |          Instance ID                          | Reserved      |
40  *     +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
41  */
42 
43 void
44 otv_print(const u_char *bp, u_int len)
45 {
46     u_int8_t flags;
47     u_int32_t overlay_id;
48     u_int32_t instance_id;
49 
50     if (len < 8) {
51         printf("[|OTV]");
52         return;
53     }
54 
55     flags = *bp;
56     bp += 1;
57 
58     overlay_id = EXTRACT_24BITS(bp);
59     bp += 3;
60 
61     instance_id = EXTRACT_24BITS(bp);
62     bp += 4;
63 
64     printf("OTV, ");
65 
66     fputs("flags [", stdout);
67     if (flags & 0x08)
68         fputs("I", stdout);
69     else
70         fputs(".", stdout);
71     fputs("] ", stdout);
72 
73     printf("(0x%02x), ", flags);
74     printf("overlay %u, ", overlay_id);
75     printf("instance %u\n", instance_id);
76 
77     ether_print(gndo, bp, len - 8, len - 8, NULL, NULL);
78     return;
79 }
80