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 1.10 2024/09/02 16:15:33 christos Exp $"); 20 #endif 21 22 /* \summary: Syslog protocol printer */ 23 /* specification: RFC 3164 (not RFC 5424) */ 24 25 #include <config.h> 26 27 #include "netdissect-stdinc.h" 28 29 #include "netdissect.h" 30 #include "extract.h" 31 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 of priority digits to read in. */ 41 42 static 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 54 static 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 82 void 83 syslog_print(netdissect_options *ndo, 84 const u_char *pptr, u_int len) 85 { 86 uint16_t msg_off = 0; 87 uint16_t pri = 0; 88 uint16_t facility,severity; 89 90 ndo->ndo_protocol = "syslog"; 91 /* extract decimal figures that are 92 * encapsulated within < > tags 93 * based on this decimal figure extract the 94 * severity and facility values 95 */ 96 97 if (GET_U_1(pptr) != '<') 98 goto invalid; 99 msg_off++; 100 101 while (msg_off <= SYSLOG_MAX_DIGITS && 102 GET_U_1(pptr + msg_off) >= '0' && 103 GET_U_1(pptr + msg_off) <= '9') { 104 pri = pri * 10 + (GET_U_1(pptr + msg_off) - '0'); 105 msg_off++; 106 } 107 108 if (GET_U_1(pptr + msg_off) != '>') 109 goto invalid; 110 msg_off++; 111 112 facility = (pri & SYSLOG_FACILITY_MASK) >> 3; 113 severity = pri & SYSLOG_SEVERITY_MASK; 114 115 if (ndo->ndo_vflag < 1 ) { 116 ND_PRINT("SYSLOG %s.%s, length: %u", 117 tok2str(syslog_facility_values, "unknown (%u)", facility), 118 tok2str(syslog_severity_values, "unknown (%u)", severity), 119 len); 120 return; 121 } 122 123 ND_PRINT("SYSLOG, length: %u\n\tFacility %s (%u), Severity %s (%u)\n\tMsg: ", 124 len, 125 tok2str(syslog_facility_values, "unknown (%u)", facility), 126 facility, 127 tok2str(syslog_severity_values, "unknown (%u)", severity), 128 severity); 129 130 /* print the syslog text in verbose mode */ 131 /* 132 * RFC 3164 Section 4.1.3: "There is no ending delimiter to this part. 133 * The MSG part of the syslog packet MUST contain visible (printing) 134 * characters." 135 * 136 * RFC 5424 Section 8.2: "This document does not impose any mandatory 137 * restrictions on the MSG or PARAM-VALUE content. As such, they MAY 138 * contain control characters, including the NUL character." 139 * 140 * Hence, to aid in protocol debugging, print the full MSG without 141 * beautification to make it clear what was transmitted on the wire. 142 */ 143 if (len > msg_off) 144 (void)nd_printn(ndo, pptr + msg_off, len - msg_off, NULL); 145 146 if (ndo->ndo_vflag > 1) 147 print_unknown_data(ndo, pptr, "\n\t", len); 148 return; 149 150 invalid: 151 nd_print_invalid(ndo); 152 } 153