xref: /freebsd/usr.bin/logger/logger.c (revision 3416500aef140042c64bc149cb1ec6620483bc44)
1 /*
2  * Copyright (c) 1983, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #ifndef lint
31 static const char copyright[] =
32 "@(#) Copyright (c) 1983, 1993\n\
33 	The Regents of the University of California.  All rights reserved.\n";
34 #endif /* not lint */
35 
36 #if 0
37 #ifndef lint
38 static char sccsid[] = "@(#)logger.c	8.1 (Berkeley) 6/6/93";
39 #endif /* not lint */
40 #endif
41 
42 #include <sys/cdefs.h>
43 __FBSDID("$FreeBSD$");
44 
45 #include <sys/types.h>
46 #include <sys/socket.h>
47 #include <netinet/in.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <netdb.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <string.h>
55 #include <unistd.h>
56 
57 #define	SYSLOG_NAMES
58 #include <syslog.h>
59 
60 #define	sstosa(ss)	((struct sockaddr *)(void *)ss)
61 
62 struct socks {
63 	int sk_sock;
64 	int sk_addrlen;
65 	struct sockaddr_storage sk_addr;
66 };
67 
68 static int	decode(char *, const CODE *);
69 static int	pencode(char *);
70 static ssize_t	socksetup(const char *, const char *, const char *,
71 		    struct socks **);
72 static void	logmessage(int, const char *, struct socks *, ssize_t,
73 			   const char *);
74 static void	usage(void);
75 
76 #ifdef INET6
77 static int family = PF_UNSPEC;	/* protocol family (IPv4, IPv6 or both) */
78 #else
79 static int family = PF_INET;	/* protocol family (IPv4 only) */
80 #endif
81 static int send_to_all = 0;	/* send message to all IPv4/IPv6 addresses */
82 
83 /*
84  * logger -- read and log utility
85  *
86  *	Reads from an input and arranges to write the result on the system
87  *	log.
88  */
89 int
90 main(int argc, char *argv[])
91 {
92 	struct socks *socks;
93 	ssize_t nsock;
94 	int ch, logflags, pri;
95 	char *tag, *host, buf[1024];
96 	const char *svcname, *src;
97 
98 	tag = NULL;
99 	host = NULL;
100 	svcname = "syslog";
101 	src = NULL;
102 	socks = NULL;
103 	pri = LOG_USER | LOG_NOTICE;
104 	logflags = 0;
105 	unsetenv("TZ");
106 	while ((ch = getopt(argc, argv, "46Af:h:iP:p:S:st:")) != -1)
107 		switch((char)ch) {
108 		case '4':
109 			family = PF_INET;
110 			break;
111 #ifdef INET6
112 		case '6':
113 			family = PF_INET6;
114 			break;
115 #endif
116 		case 'A':
117 			send_to_all++;
118 			break;
119 		case 'f':		/* file to log */
120 			if (freopen(optarg, "r", stdin) == NULL)
121 				err(1, "%s", optarg);
122 			setvbuf(stdin, 0, _IONBF, 0);
123 			break;
124 		case 'h':		/* hostname to deliver to */
125 			host = optarg;
126 			break;
127 		case 'i':		/* log process id also */
128 			logflags |= LOG_PID;
129 			break;
130 		case 'P':		/* service name or port number */
131 			svcname = optarg;
132 			break;
133 		case 'p':		/* priority */
134 			pri = pencode(optarg);
135 			break;
136 		case 's':		/* log to standard error */
137 			logflags |= LOG_PERROR;
138 			break;
139 		case 'S':		/* source address */
140 			src = optarg;
141 			break;
142 		case 't':		/* tag */
143 			tag = optarg;
144 			break;
145 		case '?':
146 		default:
147 			usage();
148 		}
149 	argc -= optind;
150 	argv += optind;
151 
152 	if (host) {
153 		nsock = socksetup(src, host, svcname, &socks);
154 		if (nsock <= 0)
155 			errx(1, "socket");
156 	} else {
157 		if (src)
158 			errx(1, "-h option is missing.");
159 		nsock = 0;
160 	}
161 
162 	if (tag == NULL)
163 		tag = getlogin();
164 	/* setup for logging */
165 	if (host == NULL)
166 		openlog(tag, logflags, 0);
167 	(void) fclose(stdout);
168 
169 	/* log input line if appropriate */
170 	if (argc > 0) {
171 		char *p, *endp;
172 		size_t len;
173 
174 		for (p = buf, endp = buf + sizeof(buf) - 2; *argv;) {
175 			len = strlen(*argv);
176 			if (p + len > endp && p > buf) {
177 				logmessage(pri, tag, socks, nsock, buf);
178 				p = buf;
179 			}
180 			if (len > sizeof(buf) - 1)
181 				logmessage(pri, tag, socks, nsock, *argv++);
182 			else {
183 				if (p != buf)
184 					*p++ = ' ';
185 				bcopy(*argv++, p, len);
186 				*(p += len) = '\0';
187 			}
188 		}
189 		if (p != buf)
190 			logmessage(pri, tag, socks, nsock, buf);
191 	} else
192 		while (fgets(buf, sizeof(buf), stdin) != NULL)
193 			logmessage(pri, tag, socks, nsock, buf);
194 	exit(0);
195 }
196 
197 static ssize_t
198 socksetup(const char *src, const char *dst, const char *svcname,
199 	struct socks **socks)
200 {
201 	struct addrinfo hints, *res, *res0;
202 	struct sockaddr_storage *ss_src[AF_MAX];
203 	struct socks *sk;
204 	ssize_t nsock = 0;
205 	int error, maxs;
206 
207 	memset(&ss_src[0], 0, sizeof(ss_src));
208 	if (src) {
209 		char *p, *p0, *hs, *hbuf, *sbuf;
210 
211 		hbuf = sbuf = NULL;
212 		p0 = p = strdup(src);
213 		if (p0 == NULL)
214 			err(1, "strdup failed");
215 		hs = p0;	/* point to search ":" */
216 #ifdef INET6
217 		/* -S option supports IPv6 addr in "[2001:db8::1]:service". */
218 		if (*p0 == '[') {
219 			p = strchr(p0, ']');
220 			if (p == NULL)
221 				errx(1, "\"]\" not found in src addr");
222 			*p = '\0';
223 			/* hs points just after ']' (':' or '\0'). */
224 			hs = p + 1;
225 			/*
226 			 * p points just after '[' while it points hs
227 			 * in the case of [].
228 			 */
229 			p = ((p0 + 1) == (hs - 1)) ? hs : p0 + 1;
230 		}
231 #endif
232 		if (*p != '\0') {
233 			/* (p == hs) means ":514" or "[]:514". */
234 			hbuf = (p == hs && *p == ':') ? NULL : p;
235 			p = strchr(hs, ':');
236 			if (p != NULL) {
237 				*p = '\0';
238 				sbuf = (*(p + 1) != '\0') ? p + 1 : NULL;
239 			}
240 		}
241 		hints = (struct addrinfo){
242 			.ai_family = family,
243 			.ai_socktype = SOCK_DGRAM,
244 			.ai_flags = AI_PASSIVE
245 		};
246 		error = getaddrinfo(hbuf, sbuf, &hints, &res0);
247 		if (error)
248 			errx(1, "%s: %s", gai_strerror(error), src);
249 		for (res = res0; res; res = res->ai_next) {
250 			switch (res->ai_family) {
251 			case AF_INET:
252 #ifdef INET6
253 			case AF_INET6:
254 #endif
255 				if (ss_src[res->ai_family] != NULL)
256 					continue;
257 				ss_src[res->ai_family] =
258 				    malloc(sizeof(struct sockaddr_storage));
259 				if (ss_src[res->ai_family] == NULL)
260 					err(1, "malloc failed");
261 				memcpy(ss_src[res->ai_family], res->ai_addr,
262 				    res->ai_addrlen);
263 			}
264 		}
265 		freeaddrinfo(res0);
266 		free(p0);
267 	}
268 
269 	/* resolve hostname */
270 	hints = (struct addrinfo){
271 		.ai_family = family,
272 		.ai_socktype = SOCK_DGRAM
273 	};
274 	error = getaddrinfo(dst, svcname, &hints, &res0);
275 	if (error == EAI_SERVICE) {
276 		warnx("%s/udp: unknown service", svcname);
277 		error = getaddrinfo(dst, "514", &hints, &res);
278 	}
279 	if (error)
280 		errx(1, "%s: %s", gai_strerror(error), dst);
281 	/* count max number of sockets we may open */
282 	maxs = 0;
283 	for (res = res0; res; res = res->ai_next)
284 		maxs++;
285 	sk = calloc(maxs, sizeof(*sk));
286 	if (sk == NULL)
287 		errx(1, "couldn't allocate memory for sockets");
288 	for (res = res0; res; res = res->ai_next) {
289 		int s;
290 
291 		s = socket(res->ai_family, res->ai_socktype,
292 		    res->ai_protocol);
293 		if (s < 0)
294 			continue;
295 		if (src && ss_src[res->ai_family] == NULL)
296 			errx(1, "address family mismatch");
297 
298 		if (ss_src[res->ai_family]) {
299 			error = bind(s, sstosa(ss_src[res->ai_family]),
300 				    ss_src[res->ai_family]->ss_len);
301 			if (error < 0)
302 				err(1, "bind");
303 		}
304 		sk[nsock] = (struct socks){
305 			.sk_addrlen = res->ai_addrlen,
306 			.sk_sock = s
307 		};
308 		memcpy(&sk[nsock].sk_addr, res->ai_addr, res->ai_addrlen);
309 		nsock++;
310 	}
311 	freeaddrinfo(res0);
312 
313 	*socks = sk;
314 	return (nsock);
315 }
316 
317 /*
318  *  Send the message to syslog, either on the local host, or on a remote host
319  */
320 static void
321 logmessage(int pri, const char *tag, struct socks *sk, ssize_t nsock,
322 	const char *buf)
323 {
324 	char *line;
325 	int len, i, lsent;
326 
327 	if (nsock == 0) {
328 		syslog(pri, "%s", buf);
329 		return;
330 	}
331 	if ((len = asprintf(&line, "<%d>%s: %s", pri, tag, buf)) == -1)
332 		errx(1, "asprintf");
333 
334 	lsent = -1;
335 	for (i = 0; i < nsock; i++) {
336 		lsent = sendto(sk[i].sk_sock, line, len, 0,
337 			       sstosa(&sk[i].sk_addr), sk[i].sk_addrlen);
338 		if (lsent == len && !send_to_all)
339 			break;
340 	}
341 	if (lsent != len) {
342 		if (lsent == -1)
343 			warn("sendto");
344 		else
345 			warnx("sendto: short send - %d bytes", lsent);
346 	}
347 
348 	free(line);
349 }
350 
351 /*
352  *  Decode a symbolic name to a numeric value
353  */
354 static int
355 pencode(char *s)
356 {
357 	char *save;
358 	int fac, lev;
359 
360 	for (save = s; *s && *s != '.'; ++s);
361 	if (*s) {
362 		*s = '\0';
363 		fac = decode(save, facilitynames);
364 		if (fac < 0)
365 			errx(1, "unknown facility name: %s", save);
366 		*s++ = '.';
367 	}
368 	else {
369 		fac = 0;
370 		s = save;
371 	}
372 	lev = decode(s, prioritynames);
373 	if (lev < 0)
374 		errx(1, "unknown priority name: %s", save);
375 	return ((lev & LOG_PRIMASK) | (fac & LOG_FACMASK));
376 }
377 
378 static int
379 decode(char *name, const CODE *codetab)
380 {
381 	const CODE *c;
382 
383 	if (isdigit(*name))
384 		return (atoi(name));
385 
386 	for (c = codetab; c->c_name; c++)
387 		if (!strcasecmp(name, c->c_name))
388 			return (c->c_val);
389 
390 	return (-1);
391 }
392 
393 static void
394 usage(void)
395 {
396 	(void)fprintf(stderr, "usage: %s\n",
397 	    "logger [-46Ais] [-f file] [-h host] [-P port] [-p pri] [-t tag]\n"
398 	    "              [-S addr:port] [message ...]"
399 	    );
400 	exit(1);
401 }
402