print-syslog.c revision 1.6 
1/*
2 * Copyright (c) 1998-2004  Hannes Gredler <hannes@tcpdump.org>
3 *      The TCPDUMP project
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that: (1) source code
7 * distributions retain the above copyright notice and this paragraph
8 * in its entirety, and (2) distributions including binary code include
9 * the above copyright notice and this paragraph in its entirety in
10 * the documentation or other materials provided with the distribution.
11 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND
12 * WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT
13 * LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
14 * FOR A PARTICULAR PURPOSE.
15 */
16
17#include <sys/cdefs.h>
18#ifndef lint
19__RCSID("$NetBSD: print-syslog.c,v 1.6 2017/01/24 23:29:14 christos Exp $");
20#endif
21
22#ifdef HAVE_CONFIG_H
23#include "config.h"
24#endif
25
26#include <netdissect-stdinc.h>
27
28#include "netdissect.h"
29#include "extract.h"
30
31static const char tstr[] = "[|syslog]";
32
33/*
34 * tokenlists and #defines taken from Ethereal - Network traffic analyzer
35 * by Gerald Combs <gerald@ethereal.com>
36 */
37
38#define SYSLOG_SEVERITY_MASK 0x0007  /* 0000 0000 0000 0111 */
39#define SYSLOG_FACILITY_MASK 0x03f8  /* 0000 0011 1111 1000 */
40#define SYSLOG_MAX_DIGITS 3 /* The maximum number if priority digits to read in. */
41
42static const struct tok syslog_severity_values[] = {
43  { 0,      "emergency" },
44  { 1,      "alert" },
45  { 2,      "critical" },
46  { 3,      "error" },
47  { 4,      "warning" },
48  { 5,      "notice" },
49  { 6,      "info" },
50  { 7,      "debug" },
51  { 0, NULL },
52};
53
54static const struct tok syslog_facility_values[] = {
55  { 0,     "kernel" },
56  { 1,     "user" },
57  { 2,     "mail" },
58  { 3,     "daemon" },
59  { 4,     "auth" },
60  { 5,     "syslog" },
61  { 6,     "lpr" },
62  { 7,     "news" },
63  { 8,     "uucp" },
64  { 9,     "cron" },
65  { 10,    "authpriv" },
66  { 11,    "ftp" },
67  { 12,    "ntp" },
68  { 13,    "security" },
69  { 14,    "console" },
70  { 15,    "cron" },
71  { 16,    "local0" },
72  { 17,    "local1" },
73  { 18,    "local2" },
74  { 19,    "local3" },
75  { 20,    "local4" },
76  { 21,    "local5" },
77  { 22,    "local6" },
78  { 23,    "local7" },
79  { 0, NULL },
80};
81
82void
83syslog_print(netdissect_options *ndo,
84             register const u_char *pptr, register u_int len)
85{
86    uint16_t msg_off = 0;
87    uint16_t pri = 0;
88    uint16_t facility,severity;
89
90    /* extract decimal figures that are
91     * encapsulated within < > tags
92     * based on this decimal figure extract the
93     * severity and facility values
94     */
95
96    ND_TCHECK2(*pptr, 1);
97    if (*(pptr+msg_off) == '<') {
98        msg_off++;
99        ND_TCHECK2(*(pptr + msg_off), 1);
100        while ( *(pptr+msg_off) >= '0' &&
101                *(pptr+msg_off) <= '9' &&
102                msg_off <= SYSLOG_MAX_DIGITS) {
103            pri = pri * 10 + (*(pptr+msg_off) - '0');
104            msg_off++;
105            ND_TCHECK2(*(pptr + msg_off), 1);
106        }
107        if (*(pptr+msg_off) != '>') {
108            ND_PRINT((ndo, "%s", tstr));
109            return;
110        }
111        msg_off++;
112    } else {
113        ND_PRINT((ndo, "%s", tstr));
114        return;
115    }
116
117    facility = (pri & SYSLOG_FACILITY_MASK) >> 3;
118    severity = pri & SYSLOG_SEVERITY_MASK;
119
120    if (ndo->ndo_vflag < 1 )
121    {
122        ND_PRINT((ndo, "SYSLOG %s.%s, length: %u",
123               tok2str(syslog_facility_values, "unknown (%u)", facility),
124               tok2str(syslog_severity_values, "unknown (%u)", severity),
125               len));
126        return;
127    }
128
129    ND_PRINT((ndo, "SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ",
130           len,
131           tok2str(syslog_facility_values, "unknown (%u)", facility),
132           facility,
133           tok2str(syslog_severity_values, "unknown (%u)", severity),
134           severity));
135
136    /* print the syslog text in verbose mode */
137    for (; msg_off < len; msg_off++) {
138        ND_TCHECK2(*(pptr + msg_off), 1);
139        safeputchar(ndo, *(pptr + msg_off));
140    }
141
142    if (ndo->ndo_vflag > 1)
143        print_unknown_data(ndo, pptr, "\n\t", len);
144
145    return;
146
147trunc:
148    ND_PRINT((ndo, "%s", tstr));
149}
150