xref: /freebsd/usr.bin/logger/logger.c (revision a04667ab172598d17ccf33d73ba13f427982527a)
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  * 4. 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 	pri = LOG_USER | LOG_NOTICE;
103 	logflags = 0;
104 	unsetenv("TZ");
105 	while ((ch = getopt(argc, argv, "46Af:h:iP:p:S:st:")) != -1)
106 		switch((char)ch) {
107 		case '4':
108 			family = PF_INET;
109 			break;
110 #ifdef INET6
111 		case '6':
112 			family = PF_INET6;
113 			break;
114 #endif
115 		case 'A':
116 			send_to_all++;
117 			break;
118 		case 'f':		/* file to log */
119 			if (freopen(optarg, "r", stdin) == NULL)
120 				err(1, "%s", optarg);
121 			setvbuf(stdin, 0, _IONBF, 0);
122 			break;
123 		case 'h':		/* hostname to deliver to */
124 			host = optarg;
125 			break;
126 		case 'i':		/* log process id also */
127 			logflags |= LOG_PID;
128 			break;
129 		case 'P':		/* service name or port number */
130 			svcname = optarg;
131 			break;
132 		case 'p':		/* priority */
133 			pri = pencode(optarg);
134 			break;
135 		case 's':		/* log to standard error */
136 			logflags |= LOG_PERROR;
137 			break;
138 		case 'S':		/* source address */
139 			src = optarg;
140 			break;
141 		case 't':		/* tag */
142 			tag = optarg;
143 			break;
144 		case '?':
145 		default:
146 			usage();
147 		}
148 	argc -= optind;
149 	argv += optind;
150 
151 	if (host) {
152 		nsock = socksetup(src, host, svcname, &socks);
153 		if (nsock <= 0)
154 			errx(1, "socket");
155 	} else {
156 		if (src)
157 			errx(1, "-h option is missing.");
158 		nsock = 0;
159 	}
160 
161 	if (tag == NULL)
162 		tag = getlogin();
163 	/* setup for logging */
164 	if (host == NULL)
165 		openlog(tag, logflags, 0);
166 	(void) fclose(stdout);
167 
168 	/* log input line if appropriate */
169 	if (argc > 0) {
170 		char *p, *endp;
171 		size_t len;
172 
173 		for (p = buf, endp = buf + sizeof(buf) - 2; *argv;) {
174 			len = strlen(*argv);
175 			if (p + len > endp && p > buf) {
176 				logmessage(pri, tag, socks, nsock, buf);
177 				p = buf;
178 			}
179 			if (len > sizeof(buf) - 1)
180 				logmessage(pri, tag, socks, nsock, *argv++);
181 			else {
182 				if (p != buf)
183 					*p++ = ' ';
184 				bcopy(*argv++, p, len);
185 				*(p += len) = '\0';
186 			}
187 		}
188 		if (p != buf)
189 			logmessage(pri, tag, socks, nsock, buf);
190 	} else
191 		while (fgets(buf, sizeof(buf), stdin) != NULL)
192 			logmessage(pri, tag, socks, nsock, buf);
193 	exit(0);
194 }
195 
196 static ssize_t
197 socksetup(const char *src, const char *dst, const char *svcname,
198 	struct socks **socks)
199 {
200 	struct addrinfo hints, *res, *res0;
201 	struct sockaddr_storage *ss_src[AF_MAX];
202 	struct socks *sk;
203 	ssize_t nsock = 0;
204 	int error, maxs;
205 
206 	memset(&ss_src[0], 0, sizeof(ss_src));
207 	if (src) {
208 		char *p, *p0, *hs, *hbuf, *sbuf;
209 
210 		hbuf = sbuf = NULL;
211 		p0 = p = strdup(src);
212 		if (p0 == NULL)
213 			err(1, "strdup failed");
214 		hs = p0;	/* point to search ":" */
215 #ifdef INET6
216 		/* -S option supports IPv6 addr in "[2001:db8::1]:service". */
217 		if (*p0 == '[') {
218 			p = strchr(p0, ']');
219 			if (p == NULL)
220 				errx(1, "\"]\" not found in src addr");
221 			*p = '\0';
222 			/* hs points just after ']' (':' or '\0'). */
223 			hs = p + 1;
224 			/*
225 			 * p points just after '[' while it points hs
226 			 * in the case of [].
227 			 */
228 			p = ((p0 + 1) == (hs - 1)) ? hs : p0 + 1;
229 		}
230 #endif
231 		if (*p != '\0') {
232 			/* (p == hs) means ":514" or "[]:514". */
233 			hbuf = (p == hs && *p == ':') ? NULL : p;
234 			p = strchr(hs, ':');
235 			if (p != NULL) {
236 				*p = '\0';
237 				sbuf = (*(p + 1) != '\0') ? p + 1 : NULL;
238 			}
239 		}
240 		hints = (struct addrinfo){
241 			.ai_family = family,
242 			.ai_socktype = SOCK_DGRAM,
243 			.ai_flags = AI_PASSIVE
244 		};
245 		error = getaddrinfo(hbuf, sbuf, &hints, &res0);
246 		if (error)
247 			errx(1, "%s: %s", gai_strerror(error), src);
248 		for (res = res0; res; res = res->ai_next) {
249 			switch (res->ai_family) {
250 			case AF_INET:
251 #ifdef INET6
252 			case AF_INET6:
253 #endif
254 				if (ss_src[res->ai_family] != NULL)
255 					continue;
256 				ss_src[res->ai_family] =
257 				    malloc(sizeof(struct sockaddr_storage));
258 				if (ss_src[res->ai_family] == NULL)
259 					err(1, "malloc failed");
260 				memcpy(ss_src[res->ai_family], res->ai_addr,
261 				    res->ai_addrlen);
262 			}
263 		}
264 		freeaddrinfo(res0);
265 		free(p0);
266 	}
267 
268 	/* resolve hostname */
269 	hints = (struct addrinfo){
270 		.ai_family = family,
271 		.ai_socktype = SOCK_DGRAM
272 	};
273 	error = getaddrinfo(dst, svcname, &hints, &res0);
274 	if (error == EAI_SERVICE) {
275 		warnx("%s/udp: unknown service", svcname);
276 		error = getaddrinfo(dst, "514", &hints, &res);
277 	}
278 	if (error)
279 		errx(1, "%s: %s", gai_strerror(error), dst);
280 	/* count max number of sockets we may open */
281 	maxs = 0;
282 	for (res = res0; res; res = res->ai_next)
283 		maxs++;
284 	sk = calloc(maxs, sizeof(*sk));
285 	if (sk == NULL)
286 		errx(1, "couldn't allocate memory for sockets");
287 	for (res = res0; res; res = res->ai_next) {
288 		int s;
289 
290 		s = socket(res->ai_family, res->ai_socktype,
291 		    res->ai_protocol);
292 		if (s < 0)
293 			continue;
294 		if (src && ss_src[res->ai_family] == NULL)
295 			errx(1, "address family mismatch");
296 
297 		if (ss_src[res->ai_family]) {
298 			error = bind(s, sstosa(ss_src[res->ai_family]),
299 				    ss_src[res->ai_family]->ss_len);
300 			if (error < 0)
301 				err(1, "bind");
302 		}
303 		sk[nsock] = (struct socks){
304 			.sk_addrlen = res->ai_addrlen,
305 			.sk_sock = s
306 		};
307 		memcpy(&sk[nsock].sk_addr, res->ai_addr, res->ai_addrlen);
308 		nsock++;
309 	}
310 	freeaddrinfo(res0);
311 
312 	*socks = sk;
313 	return (nsock);
314 }
315 
316 /*
317  *  Send the message to syslog, either on the local host, or on a remote host
318  */
319 static void
320 logmessage(int pri, const char *tag, struct socks *sk, ssize_t nsock,
321 	const char *buf)
322 {
323 	char *line;
324 	int len, i, lsent;
325 
326 	if (nsock == 0) {
327 		syslog(pri, "%s", buf);
328 		return;
329 	}
330 	if ((len = asprintf(&line, "<%d>%s: %s", pri, tag, buf)) == -1)
331 		errx(1, "asprintf");
332 
333 	lsent = -1;
334 	for (i = 0; i < nsock; i++) {
335 		lsent = sendto(sk[i].sk_sock, line, len, 0,
336 			       sstosa(&sk[i].sk_addr), sk[i].sk_addrlen);
337 		if (lsent == len && !send_to_all)
338 			break;
339 	}
340 	if (lsent != len) {
341 		if (lsent == -1)
342 			warn("sendto");
343 		else
344 			warnx("sendto: short send - %d bytes", lsent);
345 	}
346 
347 	free(line);
348 }
349 
350 /*
351  *  Decode a symbolic name to a numeric value
352  */
353 static int
354 pencode(char *s)
355 {
356 	char *save;
357 	int fac, lev;
358 
359 	for (save = s; *s && *s != '.'; ++s);
360 	if (*s) {
361 		*s = '\0';
362 		fac = decode(save, facilitynames);
363 		if (fac < 0)
364 			errx(1, "unknown facility name: %s", save);
365 		*s++ = '.';
366 	}
367 	else {
368 		fac = 0;
369 		s = save;
370 	}
371 	lev = decode(s, prioritynames);
372 	if (lev < 0)
373 		errx(1, "unknown priority name: %s", save);
374 	return ((lev & LOG_PRIMASK) | (fac & LOG_FACMASK));
375 }
376 
377 static int
378 decode(char *name, const CODE *codetab)
379 {
380 	const CODE *c;
381 
382 	if (isdigit(*name))
383 		return (atoi(name));
384 
385 	for (c = codetab; c->c_name; c++)
386 		if (!strcasecmp(name, c->c_name))
387 			return (c->c_val);
388 
389 	return (-1);
390 }
391 
392 static void
393 usage(void)
394 {
395 	(void)fprintf(stderr, "usage: %s\n",
396 	    "logger [-46Ais] [-f file] [-h host] [-P port] [-p pri] [-t tag]\n"
397 	    "              [-S addr:port] [message ...]"
398 	    );
399 	exit(1);
400 }
401