1 /* 2 * Copyright (c) 1998-2004 Hannes Gredler <hannes@gredler.at> 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 1.9 2023/08/17 20:19:40 christos Exp $"); 20 #endif 21 22 /* \summary: Syslog protocol printer */ 23 /* specification: RFC 3164 (not RFC 5424) */ 24 25 #ifdef HAVE_CONFIG_H 26 #include <config.h> 27 #endif 28 29 #include "netdissect-stdinc.h" 30 31 #include "netdissect.h" 32 #include "extract.h" 33 34 35 /* 36 * tokenlists and #defines taken from Ethereal - Network traffic analyzer 37 * by Gerald Combs <gerald@ethereal.com> 38 */ 39 40 #define SYSLOG_SEVERITY_MASK 0x0007 /* 0000 0000 0000 0111 */ 41 #define SYSLOG_FACILITY_MASK 0x03f8 /* 0000 0011 1111 1000 */ 42 #define SYSLOG_MAX_DIGITS 3 /* The maximum number of priority digits to read in. */ 43 44 static const struct tok syslog_severity_values[] = { 45 { 0, "emergency" }, 46 { 1, "alert" }, 47 { 2, "critical" }, 48 { 3, "error" }, 49 { 4, "warning" }, 50 { 5, "notice" }, 51 { 6, "info" }, 52 { 7, "debug" }, 53 { 0, NULL }, 54 }; 55 56 static const struct tok syslog_facility_values[] = { 57 { 0, "kernel" }, 58 { 1, "user" }, 59 { 2, "mail" }, 60 { 3, "daemon" }, 61 { 4, "auth" }, 62 { 5, "syslog" }, 63 { 6, "lpr" }, 64 { 7, "news" }, 65 { 8, "uucp" }, 66 { 9, "cron" }, 67 { 10, "authpriv" }, 68 { 11, "ftp" }, 69 { 12, "ntp" }, 70 { 13, "security" }, 71 { 14, "console" }, 72 { 15, "cron" }, 73 { 16, "local0" }, 74 { 17, "local1" }, 75 { 18, "local2" }, 76 { 19, "local3" }, 77 { 20, "local4" }, 78 { 21, "local5" }, 79 { 22, "local6" }, 80 { 23, "local7" }, 81 { 0, NULL }, 82 }; 83 84 void 85 syslog_print(netdissect_options *ndo, 86 const u_char *pptr, u_int len) 87 { 88 uint16_t msg_off = 0; 89 uint16_t pri = 0; 90 uint16_t facility,severity; 91 92 ndo->ndo_protocol = "syslog"; 93 /* extract decimal figures that are 94 * encapsulated within < > tags 95 * based on this decimal figure extract the 96 * severity and facility values 97 */ 98 99 if (GET_U_1(pptr) != '<') 100 goto invalid; 101 msg_off++; 102 103 while (msg_off <= SYSLOG_MAX_DIGITS && 104 GET_U_1(pptr + msg_off) >= '0' && 105 GET_U_1(pptr + msg_off) <= '9') { 106 pri = pri * 10 + (GET_U_1(pptr + msg_off) - '0'); 107 msg_off++; 108 } 109 110 if (GET_U_1(pptr + msg_off) != '>') 111 goto invalid; 112 msg_off++; 113 114 facility = (pri & SYSLOG_FACILITY_MASK) >> 3; 115 severity = pri & SYSLOG_SEVERITY_MASK; 116 117 if (ndo->ndo_vflag < 1 ) 118 { 119 ND_PRINT("SYSLOG %s.%s, length: %u", 120 tok2str(syslog_facility_values, "unknown (%u)", facility), 121 tok2str(syslog_severity_values, "unknown (%u)", severity), 122 len); 123 return; 124 } 125 126 ND_PRINT("SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ", 127 len, 128 tok2str(syslog_facility_values, "unknown (%u)", facility), 129 facility, 130 tok2str(syslog_severity_values, "unknown (%u)", severity), 131 severity); 132 133 /* print the syslog text in verbose mode */ 134 /* 135 * RFC 3164 Section 4.1.3: "There is no ending delimiter to this part. 136 * The MSG part of the syslog packet MUST contain visible (printing) 137 * characters." 138 * 139 * RFC 5424 Section 8.2: "This document does not impose any mandatory 140 * restrictions on the MSG or PARAM-VALUE content. As such, they MAY 141 * contain control characters, including the NUL character." 142 * 143 * Hence, to aid in protocol debugging, print the full MSG without 144 * beautification to make it clear what was transmitted on the wire. 145 */ 146 if (len > msg_off) 147 (void)nd_printn(ndo, pptr + msg_off, len - msg_off, NULL); 148 149 if (ndo->ndo_vflag > 1) 150 print_unknown_data(ndo, pptr, "\n\t", len); 151 return; 152 153 invalid: 154 nd_print_invalid(ndo); 155 } 156