xref: /freebsd/usr.bin/logger/logger.c (revision 580d00f42fdd94ce43583cc45fe3f1d9fdff47d4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1983, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #ifndef lint
33 static const char copyright[] =
34 "@(#) Copyright (c) 1983, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n";
36 #endif /* not lint */
37 
38 #if 0
39 #ifndef lint
40 static char sccsid[] = "@(#)logger.c	8.1 (Berkeley) 6/6/93";
41 #endif /* not lint */
42 #endif
43 
44 #include <sys/cdefs.h>
45 #include <sys/capsicum.h>
46 #include <sys/param.h>
47 #include <sys/socket.h>
48 #include <netinet/in.h>
49 
50 #include <capsicum_helpers.h>
51 #include <ctype.h>
52 #include <err.h>
53 #include <netdb.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <time.h>
58 #include <unistd.h>
59 
60 #include <libcasper.h>
61 #include <casper/cap_syslog.h>
62 
63 #define	SYSLOG_NAMES
64 #include <syslog.h>
65 
66 #define	sstosa(ss)	((struct sockaddr *)(void *)ss)
67 
68 struct socks {
69 	int sk_sock;
70 	int sk_addrlen;
71 	struct sockaddr_storage sk_addr;
72 };
73 
74 static int	decode(char *, const CODE *);
75 static int	pencode(char *);
76 static ssize_t	socksetup(const char *, const char *, const char *,
77 		    struct socks **);
78 static void	logmessage(int, const char *, const char *, const char *,
79 		    struct socks *, ssize_t, const char *);
80 static void	usage(void);
81 
82 static cap_channel_t *capsyslog;
83 #ifdef INET6
84 static int family = PF_UNSPEC;	/* protocol family (IPv4, IPv6 or both) */
85 #else
86 static int family = PF_INET;	/* protocol family (IPv4 only) */
87 #endif
88 static int send_to_all = 0;	/* send message to all IPv4/IPv6 addresses */
89 
90 /*
91  * logger -- read and log utility
92  *
93  *	Reads from an input and arranges to write the result on the system
94  *	log.
95  */
96 int
97 main(int argc, char *argv[])
98 {
99 	cap_channel_t *capcas;
100 	struct socks *socks;
101 	ssize_t nsock;
102 	time_t now;
103 	int ch, logflags, pri;
104 	char *tag, *host, buf[1024], *timestamp, tbuf[26],
105 	    *hostname, hbuf[MAXHOSTNAMELEN], *pristr;
106 	const char *svcname, *src;
107 
108 	tag = NULL;
109 	host = NULL;
110 	hostname = NULL;
111 	svcname = "syslog";
112 	src = NULL;
113 	socks = NULL;
114 	pri = LOG_USER | LOG_NOTICE;
115 	pristr = NULL;
116 	logflags = 0;
117 	unsetenv("TZ");
118 	while ((ch = getopt(argc, argv, "46Af:H:h:iP:p:S:st:")) != -1)
119 		switch((char)ch) {
120 		case '4':
121 			family = PF_INET;
122 			break;
123 #ifdef INET6
124 		case '6':
125 			family = PF_INET6;
126 			break;
127 #endif
128 		case 'A':
129 			send_to_all++;
130 			break;
131 		case 'f':		/* file to log */
132 			if (freopen(optarg, "r", stdin) == NULL)
133 				err(1, "%s", optarg);
134 			setvbuf(stdin, 0, _IONBF, 0);
135 			break;
136 		case 'H':		/* hostname to set in message header */
137 			hostname = optarg;
138 			break;
139 		case 'h':		/* hostname to deliver to */
140 			host = optarg;
141 			break;
142 		case 'i':		/* log process id also */
143 			logflags |= LOG_PID;
144 			break;
145 		case 'P':		/* service name or port number */
146 			svcname = optarg;
147 			break;
148 		case 'p':		/* priority */
149 			pristr = optarg;
150 			break;
151 		case 's':		/* log to standard error */
152 			logflags |= LOG_PERROR;
153 			break;
154 		case 'S':		/* source address */
155 			src = optarg;
156 			break;
157 		case 't':		/* tag */
158 			tag = optarg;
159 			break;
160 		case '?':
161 		default:
162 			usage();
163 		}
164 	argc -= optind;
165 	argv += optind;
166 
167 	if (host) {
168 		nsock = socksetup(src, host, svcname, &socks);
169 		if (nsock <= 0)
170 			errx(1, "socket");
171 	} else {
172 		if (src)
173 			errx(1, "-h option is missing.");
174 		nsock = 0;
175 	}
176 
177 	capcas = cap_init();
178 	if (capcas == NULL)
179 		err(1, "Unable to contact Casper");
180 	caph_cache_catpages();
181 	caph_cache_tzdata();
182 	if (nsock == 0) {
183 		if (caph_enter_casper() < 0)
184 			err(1, "Unable to enter capability mode");
185 	}
186 	capsyslog = cap_service_open(capcas, "system.syslog");
187 	if (capsyslog == NULL)
188 		err(1, "Unable to open system.syslog service");
189 	cap_close(capcas);
190 
191 	if (pristr != NULL)
192 		pri = pencode(pristr);
193 	if (tag == NULL)
194 		tag = getlogin();
195 	/* setup for logging */
196 	if (host == NULL)
197 		cap_openlog(capsyslog, tag, logflags, 0);
198 
199 	if (hostname == NULL) {
200 		hostname = hbuf;
201 		(void )gethostname(hbuf, MAXHOSTNAMELEN);
202 		*strchrnul(hostname, '.') = '\0';
203 	}
204 
205 	timestamp = tbuf + 4;
206 
207 	/* log input line if appropriate */
208 	if (argc > 0) {
209 		char *p, *endp;
210 		size_t len;
211 
212 		(void )time(&now);
213 		(void )ctime_r(&now, tbuf);
214 		tbuf[19] = '\0';
215 
216 		for (p = buf, endp = buf + sizeof(buf) - 2; *argv;) {
217 			len = strlen(*argv);
218 			if (p + len > endp && p > buf) {
219 				logmessage(pri, timestamp, hostname, tag,
220 				    socks, nsock, buf);
221 				p = buf;
222 			}
223 			if (len > sizeof(buf) - 1)
224 				logmessage(pri, timestamp, hostname, tag,
225 				    socks, nsock, *argv++);
226 			else {
227 				if (p != buf)
228 					*p++ = ' ';
229 				bcopy(*argv++, p, len);
230 				*(p += len) = '\0';
231 			}
232 		}
233 		if (p != buf)
234 			logmessage(pri, timestamp, hostname, tag, socks, nsock,
235 			    buf);
236 	} else
237 		while (fgets(buf, sizeof(buf), stdin) != NULL) {
238 			(void )time(&now);
239 			(void )ctime_r(&now, tbuf);
240 			tbuf[19] = '\0';
241 
242 			logmessage(pri, timestamp, hostname, tag, socks, nsock,
243 			    buf);
244 		}
245 	exit(0);
246 }
247 
248 static ssize_t
249 socksetup(const char *src, const char *dst, const char *svcname,
250 	struct socks **socks)
251 {
252 	struct addrinfo hints, *res, *res0;
253 	struct sockaddr_storage *ss_src[AF_MAX];
254 	struct socks *sk;
255 	ssize_t nsock = 0;
256 	int error, maxs;
257 
258 	memset(&ss_src[0], 0, sizeof(ss_src));
259 	if (src) {
260 		char *p, *p0, *hs, *hbuf, *sbuf;
261 
262 		hbuf = sbuf = NULL;
263 		p0 = p = strdup(src);
264 		if (p0 == NULL)
265 			err(1, "strdup failed");
266 		hs = p0;	/* point to search ":" */
267 #ifdef INET6
268 		/* -S option supports IPv6 addr in "[2001:db8::1]:service". */
269 		if (*p0 == '[') {
270 			p = strchr(p0, ']');
271 			if (p == NULL)
272 				errx(1, "\"]\" not found in src addr");
273 			*p = '\0';
274 			/* hs points just after ']' (':' or '\0'). */
275 			hs = p + 1;
276 			/*
277 			 * p points just after '[' while it points hs
278 			 * in the case of [].
279 			 */
280 			p = ((p0 + 1) == (hs - 1)) ? hs : p0 + 1;
281 		}
282 #endif
283 		if (*p != '\0') {
284 			/* (p == hs) means ":514" or "[]:514". */
285 			hbuf = (p == hs && *p == ':') ? NULL : p;
286 			p = strchr(hs, ':');
287 			if (p != NULL) {
288 				*p = '\0';
289 				sbuf = (*(p + 1) != '\0') ? p + 1 : NULL;
290 			}
291 		}
292 		hints = (struct addrinfo){
293 			.ai_family = family,
294 			.ai_socktype = SOCK_DGRAM,
295 			.ai_flags = AI_PASSIVE
296 		};
297 		error = getaddrinfo(hbuf, sbuf, &hints, &res0);
298 		if (error)
299 			errx(1, "%s: %s", gai_strerror(error), src);
300 		for (res = res0; res; res = res->ai_next) {
301 			switch (res->ai_family) {
302 			case AF_INET:
303 #ifdef INET6
304 			case AF_INET6:
305 #endif
306 				if (ss_src[res->ai_family] != NULL)
307 					continue;
308 				ss_src[res->ai_family] =
309 				    malloc(sizeof(struct sockaddr_storage));
310 				if (ss_src[res->ai_family] == NULL)
311 					err(1, "malloc failed");
312 				memcpy(ss_src[res->ai_family], res->ai_addr,
313 				    res->ai_addrlen);
314 			}
315 		}
316 		freeaddrinfo(res0);
317 		free(p0);
318 	}
319 
320 	/* resolve hostname */
321 	hints = (struct addrinfo){
322 		.ai_family = family,
323 		.ai_socktype = SOCK_DGRAM
324 	};
325 	error = getaddrinfo(dst, svcname, &hints, &res0);
326 	if (error == EAI_SERVICE) {
327 		warnx("%s/udp: unknown service", svcname);
328 		error = getaddrinfo(dst, "514", &hints, &res0);
329 	}
330 	if (error)
331 		errx(1, "%s: %s", gai_strerror(error), dst);
332 	/* count max number of sockets we may open */
333 	maxs = 0;
334 	for (res = res0; res; res = res->ai_next)
335 		maxs++;
336 	sk = calloc(maxs, sizeof(*sk));
337 	if (sk == NULL)
338 		errx(1, "couldn't allocate memory for sockets");
339 	for (res = res0; res; res = res->ai_next) {
340 		int s;
341 
342 		s = socket(res->ai_family, res->ai_socktype,
343 		    res->ai_protocol);
344 		if (s < 0)
345 			continue;
346 		if (src && ss_src[res->ai_family] == NULL)
347 			errx(1, "address family mismatch");
348 
349 		if (ss_src[res->ai_family]) {
350 			error = bind(s, sstosa(ss_src[res->ai_family]),
351 				    ss_src[res->ai_family]->ss_len);
352 			if (error < 0)
353 				err(1, "bind");
354 		}
355 		sk[nsock] = (struct socks){
356 			.sk_addrlen = res->ai_addrlen,
357 			.sk_sock = s
358 		};
359 		memcpy(&sk[nsock].sk_addr, res->ai_addr, res->ai_addrlen);
360 		nsock++;
361 	}
362 	freeaddrinfo(res0);
363 
364 	*socks = sk;
365 	return (nsock);
366 }
367 
368 /*
369  *  Send the message to syslog, either on the local host, or on a remote host
370  */
371 static void
372 logmessage(int pri, const char *timestamp, const char *hostname,
373     const char *tag, struct socks *sk, ssize_t nsock, const char *buf)
374 {
375 	char *line;
376 	int len, i, lsent;
377 
378 	if (nsock == 0) {
379 		cap_syslog(capsyslog, pri, "%s", buf);
380 		return;
381 	}
382 	if ((len = asprintf(&line, "<%d>%s %s %s: %s", pri, timestamp,
383 	    hostname, tag, buf)) == -1)
384 		errx(1, "asprintf");
385 
386 	lsent = -1;
387 	for (i = 0; i < nsock; i++) {
388 		lsent = sendto(sk[i].sk_sock, line, len, 0,
389 			       sstosa(&sk[i].sk_addr), sk[i].sk_addrlen);
390 		if (lsent == len && !send_to_all)
391 			break;
392 	}
393 	if (lsent != len) {
394 		if (lsent == -1)
395 			warn("sendto");
396 		else
397 			warnx("sendto: short send - %d bytes", lsent);
398 	}
399 
400 	free(line);
401 }
402 
403 /*
404  *  Decode a symbolic name to a numeric value
405  */
406 static int
407 pencode(char *s)
408 {
409 	char *save;
410 	int fac, lev;
411 
412 	for (save = s; *s && *s != '.'; ++s);
413 	if (*s) {
414 		*s = '\0';
415 		fac = decode(save, facilitynames);
416 		if (fac < 0)
417 			errx(1, "unknown facility name: %s", save);
418 		*s++ = '.';
419 	}
420 	else {
421 		fac = 0;
422 		s = save;
423 	}
424 	lev = decode(s, prioritynames);
425 	if (lev < 0)
426 		errx(1, "unknown priority name: %s", save);
427 	return ((lev & LOG_PRIMASK) | (fac & LOG_FACMASK));
428 }
429 
430 static int
431 decode(char *name, const CODE *codetab)
432 {
433 	const CODE *c;
434 
435 	if (isdigit(*name))
436 		return (atoi(name));
437 
438 	for (c = codetab; c->c_name; c++)
439 		if (!strcasecmp(name, c->c_name))
440 			return (c->c_val);
441 
442 	return (-1);
443 }
444 
445 static void
446 usage(void)
447 {
448 	(void)fprintf(stderr, "usage: %s\n",
449 	    "logger [-46Ais] [-f file] [-h host] [-P port] [-p pri] [-t tag]\n"
450 	    "              [-S addr:port] [message ...]"
451 	    );
452 	exit(1);
453 }
454