1 /*
2 * Copyright (C) 2000, Richard Sharpe
3 *
4 * This software may be distributed either under the terms of the
5 * BSD-style license that accompanies tcpdump or under the GNU GPL
6 * version 2 or later.
7 *
8 * print-beep.c
9 *
10 */
11
12 /* \summary: Blocks Extensible Exchange Protocol (BEEP) printer */
13
14 #ifdef HAVE_CONFIG_H
15 #include "config.h"
16 #endif
17
18 #include <netdissect-stdinc.h>
19
20 #include <string.h>
21
22 #include "netdissect.h"
23
24 /* Check for a string but not go beyond length
25 * Return TRUE on match, FALSE otherwise
26 *
27 * Looks at the first few chars up to tl1 ...
28 */
29
30 static int
l_strnstart(netdissect_options * ndo,const char * tstr1,u_int tl1,const char * str2,u_int l2)31 l_strnstart(netdissect_options *ndo, const char *tstr1, u_int tl1,
32 const char *str2, u_int l2)
33 {
34 if (!ND_TTEST2(*str2, tl1)) {
35 /*
36 * We don't have tl1 bytes worth of captured data
37 * for the string, so we can't check for this
38 * string.
39 */
40 return 0;
41 }
42 if (tl1 > l2)
43 return 0;
44
45 return (strncmp(tstr1, str2, tl1) == 0 ? 1 : 0);
46 }
47
48 void
beep_print(netdissect_options * ndo,const u_char * bp,u_int length)49 beep_print(netdissect_options *ndo, const u_char *bp, u_int length)
50 {
51
52 if (l_strnstart(ndo, "MSG", 4, (const char *)bp, length)) /* A REQuest */
53 ND_PRINT((ndo, " BEEP MSG"));
54 else if (l_strnstart(ndo, "RPY ", 4, (const char *)bp, length))
55 ND_PRINT((ndo, " BEEP RPY"));
56 else if (l_strnstart(ndo, "ERR ", 4, (const char *)bp, length))
57 ND_PRINT((ndo, " BEEP ERR"));
58 else if (l_strnstart(ndo, "ANS ", 4, (const char *)bp, length))
59 ND_PRINT((ndo, " BEEP ANS"));
60 else if (l_strnstart(ndo, "NUL ", 4, (const char *)bp, length))
61 ND_PRINT((ndo, " BEEP NUL"));
62 else if (l_strnstart(ndo, "SEQ ", 4, (const char *)bp, length))
63 ND_PRINT((ndo, " BEEP SEQ"));
64 else if (l_strnstart(ndo, "END", 4, (const char *)bp, length))
65 ND_PRINT((ndo, " BEEP END"));
66 else
67 ND_PRINT((ndo, " BEEP (payload or undecoded)"));
68 }
69