summaryrefslogtreecommitdiffstats
path: root/plugins/pmaixforwardedfrom/pmaixforwardedfrom.c
blob: fa4a9087787b6f7a0bddb63b608b0dd611cedffe (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
/* pmaixforwardedfrom.c
 *
 * this detects logs sent by Cisco devices that mangle their syslog output when you tell them to log by name by adding ' :' between the name and the %XXX-X-XXXXXXX: tag
 * 
 * instead of actually parsing the message, this modifies the message and then falls through to allow a later parser to handle the now modified message
 *
 * created 2010-12-13 by David Lang based on pmlastmsg
 *
 * This file is part of rsyslog.
 *
 * Rsyslog is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Rsyslog is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Rsyslog.  If not, see <http://www.gnu.org/licenses/>.
 *
 * A copy of the GPL can be found in the file "COPYING" in this distribution.
 */
#include "config.h"
#include "rsyslog.h"
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <ctype.h>
#include "conf.h"
#include "syslogd-types.h"
#include "template.h"
#include "msg.h"
#include "module-template.h"
#include "glbl.h"
#include "errmsg.h"
#include "parser.h"
#include "datetime.h"
#include "unicode-helper.h"

MODULE_TYPE_PARSER
MODULE_TYPE_NOKEEP
PARSER_NAME("rsyslog.aixforwardedfrom")

/* internal structures
 */
DEF_PMOD_STATIC_DATA
DEFobjCurrIf(errmsg)
DEFobjCurrIf(glbl)
DEFobjCurrIf(parser)
DEFobjCurrIf(datetime)


/* static data */
static int bParseHOSTNAMEandTAG;	/* cache for the equally-named global param - performance enhancement */


BEGINisCompatibleWithFeature
CODESTARTisCompatibleWithFeature
	if(eFeat == sFEATUREAutomaticSanitazion)
		iRet = RS_RET_OK;
	if(eFeat == sFEATUREAutomaticPRIParsing)
		iRet = RS_RET_OK;
ENDisCompatibleWithFeature


BEGINparse
	uchar *p2parse;
	uchar *opening;
	int lenMsg;
#define OpeningText "Message forwarded from "
CODESTARTparse
	dbgprintf("Message will now be parsed by fix AIX Forwarded From parser.\n");
	assert(pMsg != NULL);
	assert(pMsg->pszRawMsg != NULL);
	lenMsg = pMsg->iLenRawMsg - pMsg->offAfterPRI; /* note: offAfterPRI is already the number of PRI chars (do not add one!) */
	p2parse = pMsg->pszRawMsg + pMsg->offAfterPRI; /* point to start of text, after PRI */

	/* check if this message is of the type we handle in this (very limited) parser */
	/* first, we permit SP */
	while(lenMsg && *p2parse == ' ') {
		--lenMsg;
		++p2parse;
	}
dbgprintf("pmaixforwardedfrom: msg to look at: [%d]'%s'\n", lenMsg, p2parse);
	if((unsigned) lenMsg < 42) {
		/* too short, can not be "our" message */
                /* minimum message, 16 character timestamp, 'Message forwarded from ", 1 character name, ': '*/
dbgprintf("msg too short!\n");
		ABORT_FINALIZE(RS_RET_COULD_NOT_PARSE);
	}

	/* skip over timestamp */
	lenMsg -=16;
	p2parse +=16;
        /* if there is the string "Message forwarded from " were the hostname should be */
	if(strncasecmp((char*) p2parse, OpeningText, sizeof(OpeningText)-1) != 0) {
		/* wrong opening text */
dbgprintf("not a AIX message forwarded from mangled log!\n");
		ABORT_FINALIZE(RS_RET_COULD_NOT_PARSE);
	}
	/* bump the message portion up by 23 characters to overwrite the "Message forwarded from " with the hostname */
	lenMsg -=23;
	memmove(p2parse, p2parse + 23, lenMsg);
	*(p2parse + lenMsg) = '\n';
	*(p2parse + lenMsg + 1)  = '\0';
	pMsg->iLenRawMsg -=23;
	pMsg->iLenMSG -=23;
	/* now look for the : after the hostname to walk past the hostname, also watch for a space in case this isn't really an AIX log, but has a similar preamble */
	while(lenMsg && *p2parse != ' ' && *p2parse != ':') {
		--lenMsg;
		++p2parse;
	}
	if (lenMsg && *p2parse != ':') {
dbgprintf("not a AIX message forwarded from mangled log but similar enough that the preamble has been removed\n");
		ABORT_FINALIZE(RS_RET_COULD_NOT_PARSE);
	}
	/* bump the message portion up by one character to overwrite the extra : */
	lenMsg -=1;
	memmove(p2parse, p2parse + 1, lenMsg);
	*(p2parse + lenMsg) = '\n';
	*(p2parse + lenMsg + 1)  = '\0';
	pMsg->iLenRawMsg -=1;
	pMsg->iLenMSG -=1;
	/* now, claim to abort so that something else can parse the now modified message */
	DBGPRINTF("pmaixforwardedfrom: new mesage: [%d]'%s'\n", lenMsg, pMsg->pszRawMsg + pMsg->offAfterPRI);
	ABORT_FINALIZE(RS_RET_COULD_NOT_PARSE);

finalize_it:
ENDparse


BEGINmodExit
CODESTARTmodExit
	/* release what we no longer need */
	objRelease(errmsg, CORE_COMPONENT);
	objRelease(glbl, CORE_COMPONENT);
	objRelease(parser, CORE_COMPONENT);
	objRelease(datetime, CORE_COMPONENT);
ENDmodExit


BEGINqueryEtryPt
CODESTARTqueryEtryPt
CODEqueryEtryPt_STD_PMOD_QUERIES
CODEqueryEtryPt_IsCompatibleWithFeature_IF_OMOD_QUERIES
ENDqueryEtryPt


BEGINmodInit()
CODESTARTmodInit
	*ipIFVersProvided = CURR_MOD_IF_VERSION; /* we only support the current interface specification */
CODEmodInit_QueryRegCFSLineHdlr
	CHKiRet(objUse(glbl, CORE_COMPONENT));
	CHKiRet(objUse(errmsg, CORE_COMPONENT));
	CHKiRet(objUse(parser, CORE_COMPONENT));
	CHKiRet(objUse(datetime, CORE_COMPONENT));

	DBGPRINTF("aixforwardedfrom parser init called, compiled with version %s\n", VERSION);
 	bParseHOSTNAMEandTAG = glbl.GetParseHOSTNAMEandTAG(); /* cache value, is set only during rsyslogd option processing */


ENDmodInit

/* vim:set ai:
 */