xref: /titanic_52/usr/src/cmd/fm/modules/common/syslog-msgs/syslog.c (revision 68c47f65208790c466e5e484f2293d3baed71c6a)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #include <sys/fm/protocol.h>
28 #include <sys/strlog.h>
29 #include <sys/log.h>
30 
31 #include <fm/fmd_api.h>
32 #include <fm/fmd_msg.h>
33 
34 #include <stropts.h>
35 #include <strings.h>
36 #include <syslog.h>
37 #include <alloca.h>
38 #include <unistd.h>
39 #include <stdlib.h>
40 #include <errno.h>
41 #include <fcntl.h>
42 
43 static struct stats {
44 	fmd_stat_t bad_vers;
45 	fmd_stat_t bad_code;
46 	fmd_stat_t log_err;
47 	fmd_stat_t msg_err;
48 	fmd_stat_t no_msg;
49 } syslog_stats = {
50 	{ "bad_vers", FMD_TYPE_UINT64, "event version is missing or invalid" },
51 	{ "bad_code", FMD_TYPE_UINT64, "event code has no dictionary name" },
52 	{ "log_err", FMD_TYPE_UINT64, "failed to log message to log(7D)" },
53 	{ "msg_err", FMD_TYPE_UINT64, "failed to log message to sysmsg(7D)" },
54 	{ "no_msg", FMD_TYPE_UINT64, "message logging suppressed" }
55 };
56 
57 static const struct facility {
58 	const char *fac_name;
59 	int fac_value;
60 } syslog_facs[] = {
61 	{ "LOG_DAEMON", LOG_DAEMON },
62 	{ "LOG_LOCAL0", LOG_LOCAL0 },
63 	{ "LOG_LOCAL1", LOG_LOCAL1 },
64 	{ "LOG_LOCAL2", LOG_LOCAL2 },
65 	{ "LOG_LOCAL3", LOG_LOCAL3 },
66 	{ "LOG_LOCAL4", LOG_LOCAL4 },
67 	{ "LOG_LOCAL5", LOG_LOCAL5 },
68 	{ "LOG_LOCAL6", LOG_LOCAL6 },
69 	{ "LOG_LOCAL7", LOG_LOCAL7 },
70 	{ NULL, 0 }
71 };
72 
73 static fmd_msg_hdl_t *syslog_msghdl; /* handle for libfmd_msg calls */
74 static int syslog_msgall;	/* set to message all faults */
75 static log_ctl_t syslog_ctl;	/* log(7D) meta-data for each msg */
76 static int syslog_logfd = -1;	/* log(7D) file descriptor */
77 static int syslog_msgfd = -1;	/* sysmsg(7D) file descriptor */
78 static int syslog_file;		/* log to syslog_logfd */
79 static int syslog_cons;		/* log to syslog_msgfd */
80 static const char SYSLOG_POINTER[] = "syslog-msgs-pointer";
81 
82 /*
83  * Ideally we would just use syslog(3C) for outputting our messages, but our
84  * messaging standard defines a nice multi-line format and syslogd(1M) is very
85  * inflexible and stupid when it comes to multi-line messages.  It pulls data
86  * out of log(7D) and splits it up by \n, printing each line to the console
87  * with its usual prefix of date and sender; it uses the same behavior for the
88  * messages file as well.  Further, syslog(3C) provides no CE_CONT equivalent
89  * for userland callers (which at least works around repeated file prefixing).
90  * So with a multi-line message format, your file and console end up like this:
91  *
92  * Dec 02 18:08:40 hostname this is my nicely formatted
93  * Dec 02 18:08:40 hostname message designed for 80 cols
94  * ...
95  *
96  * To resolve these issues, we use our own syslog_emit() wrapper to emit
97  * messages and some knowledge of how the Solaris log drivers work.  We first
98  * construct an enlarged format string containing the appropriate msgid(1).
99  * We then format the caller's message using the provided format and buffer.
100  * We send this message to log(7D) using putmsg() with SL_CONSOLE | SL_LOGONLY
101  * set in the log_ctl_t.  The log driver allows us to set SL_LOGONLY when we
102  * construct messages ourself, indicating that syslogd should only emit the
103  * message to /var/adm/messages and any remote hosts, and skip the console.
104  * Then we emit the message a second time, without the special prefix, to the
105  * sysmsg(7D) device, which handles console redirection and also permits us
106  * to output any characters we like to the console, including \n and \r.
107  */
108 static void
109 syslog_emit(fmd_hdl_t *hdl, const char *msg)
110 {
111 	struct strbuf ctl, dat;
112 	uint32_t msgid;
113 
114 	char *buf;
115 	size_t buflen;
116 
117 	const char *format = "fmd: [ID %u FACILITY_AND_PRIORITY] %s";
118 	STRLOG_MAKE_MSGID(format, msgid);
119 
120 	buflen = snprintf(NULL, 0, format, msgid, msg);
121 	buf = alloca(buflen + 1);
122 	(void) snprintf(buf, buflen + 1, format, msgid, msg);
123 
124 	ctl.buf = (void *)&syslog_ctl;
125 	ctl.len = sizeof (syslog_ctl);
126 
127 	dat.buf = buf;
128 	dat.len = buflen + 1;
129 
130 	/*
131 	 * The underlying log driver won't accept messages longer than
132 	 * LOG_MAXPS bytes.  Therefore, messages which exceed this limit will
133 	 * be truncated and appended with a pointer to the full message.
134 	 */
135 	if (dat.len > LOG_MAXPS) {
136 		char *syslog_pointer, *p;
137 		size_t plen;
138 
139 		if ((syslog_pointer = fmd_msg_gettext_id(syslog_msghdl, NULL,
140 		    SYSLOG_POINTER)) == NULL) {
141 			/*
142 			 * This shouldn't happen, but if it does we'll just
143 			 * truncate the message.
144 			 */
145 			buf[LOG_MAXPS - 1] = '\0';
146 			dat.len = LOG_MAXPS;
147 		} else {
148 			plen = strlen(syslog_pointer) + 1;
149 			buf[LOG_MAXPS - plen] = '\0';
150 			/*
151 			 * If possible, the pointer is appended after a newline
152 			 */
153 			if ((p = strrchr(buf, '\n')) == NULL)
154 				p = &buf[LOG_MAXPS - plen];
155 
156 			(void) strcpy(p, syslog_pointer);
157 			free(syslog_pointer);
158 			dat.len = strlen(buf) + 1;
159 		}
160 	}
161 	if (syslog_file && putmsg(syslog_logfd, &ctl, &dat, 0) != 0) {
162 		fmd_hdl_debug(hdl, "putmsg failed: %s\n", strerror(errno));
163 		syslog_stats.log_err.fmds_value.ui64++;
164 	}
165 
166 	dat.buf = strchr(buf, ']');
167 	dat.len -= (size_t)(dat.buf - buf);
168 
169 	dat.buf[0] = '\r'; /* overwrite ']' with carriage return */
170 	dat.buf[1] = '\n'; /* overwrite ' ' with newline */
171 
172 	if (syslog_cons && write(syslog_msgfd, dat.buf, dat.len) != dat.len) {
173 		fmd_hdl_debug(hdl, "write failed: %s\n", strerror(errno));
174 		syslog_stats.msg_err.fmds_value.ui64++;
175 	}
176 }
177 
178 /*ARGSUSED*/
179 static void
180 syslog_recv(fmd_hdl_t *hdl, fmd_event_t *ep, nvlist_t *nvl, const char *class)
181 {
182 	uint8_t version;
183 	boolean_t domsg;
184 	char *msg;
185 
186 	if (nvlist_lookup_uint8(nvl, FM_VERSION, &version) != 0 ||
187 	    version > FM_SUSPECT_VERSION) {
188 		fmd_hdl_debug(hdl, "invalid event version: %u\n", version);
189 		syslog_stats.bad_vers.fmds_value.ui64++;
190 		return; /* invalid event version */
191 	}
192 
193 	if (!syslog_msgall && nvlist_lookup_boolean_value(nvl,
194 	    FM_SUSPECT_MESSAGE, &domsg) == 0 && !domsg) {
195 		fmd_hdl_debug(hdl, "%s requested no message\n", class);
196 		syslog_stats.no_msg.fmds_value.ui64++;
197 		return; /* event is not to be messaged */
198 	}
199 
200 	if ((msg = fmd_msg_gettext_nv(syslog_msghdl, NULL, nvl)) == NULL) {
201 		fmd_hdl_debug(hdl, "failed to format message");
202 		syslog_stats.bad_code.fmds_value.ui64++;
203 		return; /* libfmd_msg error */
204 	}
205 
206 	syslog_ctl.pri &= LOG_FACMASK;
207 	if (strcmp(class, FM_LIST_RESOLVED_CLASS) == 0 ||
208 	    strcmp(class, FM_LIST_REPAIRED_CLASS) == 0)
209 		syslog_ctl.pri |= LOG_NOTICE;
210 	else
211 		syslog_ctl.pri |= LOG_ERR;
212 
213 	syslog_emit(hdl, msg);
214 	free(msg);
215 }
216 
217 static const fmd_prop_t fmd_props[] = {
218 	{ "console", FMD_TYPE_BOOL, "true" },
219 	{ "facility", FMD_TYPE_STRING, "LOG_DAEMON" },
220 	{ "gmt", FMD_TYPE_BOOL, "false" },
221 	{ "syslogd", FMD_TYPE_BOOL, "true" },
222 	{ "url", FMD_TYPE_STRING, "http://sun.com/msg/" },
223 	{ "message_all", FMD_TYPE_BOOL, "false" },
224 	{ NULL, 0, NULL }
225 };
226 
227 static const fmd_hdl_ops_t fmd_ops = {
228 	syslog_recv,	/* fmdo_recv */
229 	NULL,		/* fmdo_timeout */
230 	NULL,		/* fmdo_close */
231 	NULL,		/* fmdo_stats */
232 	NULL,		/* fmdo_gc */
233 };
234 
235 static const fmd_hdl_info_t fmd_info = {
236 	"Syslog Messaging Agent", "1.0", &fmd_ops, fmd_props
237 };
238 
239 void
240 _fmd_init(fmd_hdl_t *hdl)
241 {
242 	const struct facility *fp;
243 	char *facname, *tz, *rootdir, *urlbase;
244 
245 	if (fmd_hdl_register(hdl, FMD_API_VERSION, &fmd_info) != 0)
246 		return; /* invalid data in configuration file */
247 
248 	(void) fmd_stat_create(hdl, FMD_STAT_NOALLOC, sizeof (syslog_stats) /
249 	    sizeof (fmd_stat_t), (fmd_stat_t *)&syslog_stats);
250 
251 	if ((syslog_logfd = open("/dev/conslog", O_WRONLY | O_NOCTTY)) == -1)
252 		fmd_hdl_abort(hdl, "syslog-msgs failed to open /dev/conslog");
253 
254 	if ((syslog_msgfd = open("/dev/sysmsg", O_WRONLY | O_NOCTTY)) == -1)
255 		fmd_hdl_abort(hdl, "syslog-msgs failed to open /dev/sysmsg");
256 
257 	/*
258 	 * If the "gmt" property is set to true, force our EVENT-TIME to be
259 	 * reported in GMT time; otherwise we use localtime.  tzset() affects
260 	 * the results of subsequent calls to strftime(3C) above.
261 	 */
262 	if (fmd_prop_get_int32(hdl, "gmt") == FMD_B_TRUE &&
263 	    ((tz = getenv("TZ")) == NULL || strcmp(tz, "GMT") != 0)) {
264 		(void) putenv(fmd_hdl_strdup(hdl, "TZ=GMT", FMD_SLEEP));
265 		tzset(); /* reload env */
266 	}
267 
268 	/*
269 	 * Look up the value of the "facility" property and use it to determine
270 	 * what syslog LOG_* facility value we use to fill in our log_ctl_t.
271 	 * The details of our logging method are described above syslog_emit().
272 	 */
273 	facname = fmd_prop_get_string(hdl, "facility");
274 
275 	for (fp = syslog_facs; fp->fac_name != NULL; fp++) {
276 		if (strcmp(fp->fac_name, facname) == 0)
277 			break;
278 	}
279 
280 	if (fp->fac_name == NULL)
281 		fmd_hdl_abort(hdl, "invalid 'facility' setting: %s\n", facname);
282 
283 	fmd_prop_free_string(hdl, facname);
284 	syslog_ctl.pri = fp->fac_value;
285 	syslog_ctl.flags = SL_CONSOLE | SL_LOGONLY;
286 
287 	/*
288 	 * Cache any properties we use every time we receive an event and
289 	 * subscribe to list.suspect events regardless of the .conf file.
290 	 */
291 	syslog_file = fmd_prop_get_int32(hdl, "syslogd");
292 	syslog_cons = fmd_prop_get_int32(hdl, "console");
293 	syslog_msgall = fmd_prop_get_int32(hdl, "message_all");
294 
295 	rootdir = fmd_prop_get_string(hdl, "fmd.rootdir");
296 	syslog_msghdl = fmd_msg_init(rootdir, FMD_MSG_VERSION);
297 	fmd_prop_free_string(hdl, rootdir);
298 
299 	if (syslog_msghdl == NULL)
300 		fmd_hdl_abort(hdl, "failed to initialize libfmd_msg");
301 
302 	urlbase = fmd_prop_get_string(hdl, "url");
303 	(void) fmd_msg_url_set(syslog_msghdl, urlbase);
304 	fmd_prop_free_string(hdl, urlbase);
305 
306 	fmd_hdl_subscribe(hdl, FM_LIST_SUSPECT_CLASS);
307 	fmd_hdl_subscribe(hdl, FM_LIST_REPAIRED_CLASS);
308 	fmd_hdl_subscribe(hdl, FM_LIST_RESOLVED_CLASS);
309 }
310 
311 /*ARGSUSED*/
312 void
313 _fmd_fini(fmd_hdl_t *hdl)
314 {
315 	fmd_msg_fini(syslog_msghdl);
316 	(void) close(syslog_logfd);
317 	(void) close(syslog_msgfd);
318 }
319