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 #define NETDISSECT_REWORKED
18 #ifdef HAVE_CONFIG_H
19 #include "config.h"
20 #endif
21 
22 #include <tcpdump-stdinc.h>
23 
24 #include "interface.h"
25 #include "extract.h"
26 
27 static const char tstr[] = "[|syslog]";
28 
29 /*
30  * tokenlists and #defines taken from Ethereal - Network traffic analyzer
31  * by Gerald Combs <gerald@ethereal.com>
32  */
33 
34 #define SYSLOG_SEVERITY_MASK 0x0007  /* 0000 0000 0000 0111 */
35 #define SYSLOG_FACILITY_MASK 0x03f8  /* 0000 0011 1111 1000 */
36 #define SYSLOG_MAX_DIGITS 3 /* The maximum number if priority digits to read in. */
37 
38 static const struct tok syslog_severity_values[] = {
39   { 0,      "emergency" },
40   { 1,      "alert" },
41   { 2,      "critical" },
42   { 3,      "error" },
43   { 4,      "warning" },
44   { 5,      "notice" },
45   { 6,      "info" },
46   { 7,      "debug" },
47   { 0, NULL },
48 };
49 
50 static const struct tok syslog_facility_values[] = {
51   { 0,     "kernel" },
52   { 1,     "user" },
53   { 2,     "mail" },
54   { 3,     "daemon" },
55   { 4,     "auth" },
56   { 5,     "syslog" },
57   { 6,     "lpr" },
58   { 7,     "news" },
59   { 8,     "uucp" },
60   { 9,     "cron" },
61   { 10,    "authpriv" },
62   { 11,    "ftp" },
63   { 12,    "ntp" },
64   { 13,    "security" },
65   { 14,    "console" },
66   { 15,    "cron" },
67   { 16,    "local0" },
68   { 17,    "local1" },
69   { 18,    "local2" },
70   { 19,    "local3" },
71   { 20,    "local4" },
72   { 21,    "local5" },
73   { 22,    "local6" },
74   { 23,    "local7" },
75   { 0, NULL },
76 };
77 
78 void
syslog_print(netdissect_options * ndo,register const u_char * pptr,register u_int len)79 syslog_print(netdissect_options *ndo,
80              register const u_char *pptr, register u_int len)
81 {
82     uint16_t msg_off = 0;
83     uint16_t pri = 0;
84     uint16_t facility,severity;
85 
86     /* extract decimal figures that are
87      * encapsulated within < > tags
88      * based on this decimal figure extract the
89      * severity and facility values
90      */
91 
92     ND_TCHECK2(*pptr, 1);
93     if (*(pptr+msg_off) == '<') {
94         msg_off++;
95         ND_TCHECK2(*(pptr + msg_off), 1);
96         while ( *(pptr+msg_off) >= '0' &&
97                 *(pptr+msg_off) <= '9' &&
98                 msg_off <= SYSLOG_MAX_DIGITS) {
99             pri = pri * 10 + (*(pptr+msg_off) - '0');
100             msg_off++;
101             ND_TCHECK2(*(pptr + msg_off), 1);
102         }
103         if (*(pptr+msg_off) != '>') {
104             ND_PRINT((ndo, "%s", tstr));
105             return;
106         }
107         msg_off++;
108     } else {
109         ND_PRINT((ndo, "%s", tstr));
110         return;
111     }
112 
113     facility = (pri & SYSLOG_FACILITY_MASK) >> 3;
114     severity = pri & SYSLOG_SEVERITY_MASK;
115 
116     if (ndo->ndo_vflag < 1 )
117     {
118         ND_PRINT((ndo, "SYSLOG %s.%s, length: %u",
119                tok2str(syslog_facility_values, "unknown (%u)", facility),
120                tok2str(syslog_severity_values, "unknown (%u)", severity),
121                len));
122         return;
123     }
124 
125     ND_PRINT((ndo, "SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ",
126            len,
127            tok2str(syslog_facility_values, "unknown (%u)", facility),
128            facility,
129            tok2str(syslog_severity_values, "unknown (%u)", severity),
130            severity));
131 
132     /* print the syslog text in verbose mode */
133     for (; msg_off < len; msg_off++) {
134         ND_TCHECK2(*(pptr + msg_off), 1);
135         safeputchar(ndo, *(pptr + msg_off));
136     }
137 
138     if (ndo->ndo_vflag > 1)
139         print_unknown_data(ndo, pptr, "\n\t", len);
140 
141     return;
142 
143 trunc:
144     ND_PRINT((ndo, "%s", tstr));
145 }
146