1 /*
2  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
3  * Copyright (c) 2021 Matthias Schmidt <xhr@giessen.ccc.de>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #define _GNU_SOURCE
19 
20 #include <sys/types.h>
21 #include <sys/stat.h>
22 
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <stdarg.h>
26 #include <string.h>
27 #include <syslog.h>
28 #include <errno.h>
29 #include <fcntl.h>
30 #include <unistd.h>
31 #include <time.h>
32 
33 #include "log.h"
34 #include "twind.h"
35 
36 #define MAXLOGLINE 1024
37 
38 static int		 debug;
39 static int		 verbose;
40 static int access_fd;
41 static int error_fd;
42 
43 static const char	*log_procname;
44 
45 void
46 log_init(int n_debug, int facility)
47 {
48 	extern char	*__progname;
49 
50 	debug = n_debug;
51 	verbose = n_debug;
52 	log_procinit(__progname);
53 
54 	if (!debug)
55 		openlog(__progname, LOG_PID | LOG_NDELAY, facility);
56 
57 	tzset();
58 }
59 
60 void
61 log_procinit(const char *procname)
62 {
63 	if (procname != NULL)
64 		log_procname = procname;
65 }
66 
67 void
68 log_setverbose(int v)
69 {
70 	verbose = v;
71 }
72 
73 int
74 log_getverbose(void)
75 {
76 	return (verbose);
77 }
78 
79 void
80 logit(int pri, const char *fmt, ...)
81 {
82 	va_list	ap;
83 
84 	va_start(ap, fmt);
85 	vlog(pri, fmt, ap);
86 	va_end(ap);
87 }
88 
89 void
90 vlog(int pri, const char *fmt, va_list ap)
91 {
92 	char	*nfmt;
93 	int	 saved_errno = errno;
94 
95 	if (debug) {
96 		/* best effort in out of mem situations */
97 		if (asprintf(&nfmt, "%s\n", fmt) == -1) {
98 			vfprintf(stderr, fmt, ap);
99 			fprintf(stderr, "\n");
100 		} else {
101 			vfprintf(stderr, nfmt, ap);
102 			free(nfmt);
103 		}
104 		fflush(stderr);
105 	} else
106 		vsyslog(pri, fmt, ap);
107 
108 	errno = saved_errno;
109 }
110 
111 void
112 log_warn(const char *emsg, ...)
113 {
114 	char		*nfmt;
115 	va_list		 ap;
116 	int		 saved_errno = errno;
117 
118 	/* best effort to even work in out of memory situations */
119 	if (emsg == NULL)
120 		logit(LOG_ERR, "%s", strerror(saved_errno));
121 	else {
122 		va_start(ap, emsg);
123 
124 		if (asprintf(&nfmt, "%s: %s", emsg,
125 		    strerror(saved_errno)) == -1) {
126 			/* we tried it... */
127 			vlog(LOG_ERR, emsg, ap);
128 			logit(LOG_ERR, "%s", strerror(saved_errno));
129 		} else {
130 			vlog(LOG_ERR, nfmt, ap);
131 			free(nfmt);
132 		}
133 		va_end(ap);
134 	}
135 
136 	errno = saved_errno;
137 }
138 
139 void
140 log_warnx(const char *emsg, ...)
141 {
142 	va_list	 ap;
143 
144 	va_start(ap, emsg);
145 	vlog(LOG_ERR, emsg, ap);
146 	va_end(ap);
147 }
148 
149 void
150 log_info(const char *emsg, ...)
151 {
152 	va_list	 ap;
153 
154 	va_start(ap, emsg);
155 	vlog(LOG_INFO, emsg, ap);
156 	va_end(ap);
157 }
158 
159 void
160 log_debug(const char *emsg, ...)
161 {
162 	va_list	 ap;
163 
164 	if (verbose) {
165 		va_start(ap, emsg);
166 		vlog(LOG_DEBUG, emsg, ap);
167 		va_end(ap);
168 	}
169 }
170 
171 static void
172 vfatalc(int code, const char *emsg, va_list ap)
173 {
174 	static char	s[BUFSIZ];
175 	const char	*sep;
176 
177 	if (emsg != NULL) {
178 		(void)vsnprintf(s, sizeof(s), emsg, ap);
179 		sep = ": ";
180 	} else {
181 		s[0] = '\0';
182 		sep = "";
183 	}
184 	if (code)
185 		logit(LOG_CRIT, "fatal in %s: %s%s%s",
186 		    log_procname, s, sep, strerror(code));
187 	else
188 		logit(LOG_CRIT, "fatal in %s%s%s", log_procname, sep, s);
189 }
190 
191 void
192 fatal(const char *emsg, ...)
193 {
194 	va_list	ap;
195 
196 	va_start(ap, emsg);
197 	vfatalc(errno, emsg, ap);
198 	va_end(ap);
199 	exit(1);
200 }
201 
202 void
203 fatalx(const char *emsg, ...)
204 {
205 	va_list	ap;
206 
207 	va_start(ap, emsg);
208 	vfatalc(0, emsg, ap);
209 	va_end(ap);
210 	exit(1);
211 }
212 
213 void
214 open_twind_logs(void)
215 {
216 	if ((access_fd = open(_PATH_TWIND_ACCESS_LOG, O_WRONLY|O_APPEND|O_CREAT, 0644))
217 		== -1)
218 		fatalx("Cannot open access log: %s", _PATH_TWIND_ACCESS_LOG);
219 
220 	if ((error_fd = open(_PATH_TWIND_ERROR_LOG, O_WRONLY|O_APPEND|O_CREAT, 0644))
221 		== -1)
222 		fatalx("Cannot open error log: %s", _PATH_TWIND_ACCESS_LOG);
223 
224 	log_debug("Log files open");
225 }
226 
227 void
228 close_twind_logs(void)
229 {
230 	log_debug("Closing log file");
231 	close(access_fd);
232 	close(error_fd);
233 }
234 
235 void
236 log_access(const struct client_connection *cc, const char *fmt, ...)
237 {
238 	char tmstr[29];
239 	struct tm tm;
240 	time_t t;
241 
242 	t = time(NULL);
243 	tm = *localtime(&t);
244 
245 	if (strftime(tmstr, sizeof(tmstr), "%d/%b/%Y:%H:%M:%S %Z", &tm) == 0) {
246 		log_warn("strftime couldn't save time string");
247 		return;
248 	}
249 
250 	user_log(0, "%s - - [%s] %s", cc->client_addr, tmstr, fmt);
251 }
252 
253 void
254 log_error(const struct client_connection *cc, const char *fmt, ...)
255 {
256 	char tmstr[29];
257 	struct tm tm;
258 	time_t t;
259 
260 	t = time(NULL);
261 	tm = *localtime(&t);
262 	if (strftime(tmstr, sizeof(tmstr), "%d/%b/%Y:%H:%M:%S %Z", &tm) == 0) {
263 		log_warn("strftime couldn't save time string");
264 		return;
265 	}
266 
267 	user_log(1, "[%s] [error] [client %s] %s", tmstr,
268 			cc->client_addr, fmt);
269 }
270 
271 void
272 user_log(int target, const char *fmt, ...)
273 {
274 	va_list ap;
275 	int fd = -1;
276 
277 	va_start(ap, fmt);
278 	if (target == 0)
279 		fd = access_fd;
280 	else if (target == 1)
281 		fd = error_fd;
282 	else {
283 		log_warn("Non-existent user log target");
284 		return;
285 	}
286 
287 	vdprintf(fd, fmt, ap);
288 	dprintf(fd, "\n");
289 
290 	va_end(ap);
291 }