1 /*
2  * Copyright (c) 2021 Omar Polo <op@omarpolo.com>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "gmid.h"
18 
19 #include <sys/types.h>
20 #include <sys/uio.h>
21 
22 #include <errno.h>
23 #include <event.h>
24 #include <imsg.h>
25 #include <netdb.h>
26 #include <stdarg.h>
27 #include <stdio.h>
28 #include <string.h>
29 #include <syslog.h>
30 
31 static struct event inlog;
32 
33 static void handle_log(int, short, void*);
34 
35 void
36 fatal(const char *fmt, ...)
37 {
38 	va_list ap;
39 
40 	va_start(ap, fmt);
41 
42 	if (conf.foreground) {
43 		vfprintf(stderr, fmt, ap);
44 		fprintf(stderr, "\n");
45 	} else
46 		vsyslog(LOG_DAEMON | LOG_CRIT, fmt, ap);
47 
48 	va_end(ap);
49 	exit(1);
50 }
51 
52 static inline int
53 should_log(int priority)
54 {
55 	switch (priority) {
56 	case LOG_ERR:
57 		return 1;
58 	case LOG_WARNING:
59 		return 1;
60 	case LOG_NOTICE:
61 		return conf.verbose >= 1;
62 	case LOG_INFO:
63 		return conf.verbose >= 2;
64 	case LOG_DEBUG:
65 		return conf.verbose >= 3;
66 	default:
67 		return 0;
68 	}
69 }
70 
71 static inline void
72 send_log(const char *msg, size_t len)
73 {
74 	imsg_compose(&logpibuf, 0, 0, 0, -1, msg, len);
75 	/* XXX: use event_once() */
76 	imsg_flush(&logpibuf);
77 }
78 
79 static inline void
80 vlog(int priority, struct client *c,
81     const char *fmt, va_list ap)
82 {
83 	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
84 	char *fmted, *s;
85 	size_t len;
86 	int ec;
87 
88 	if (!should_log(priority))
89 		return;
90 
91 	if (c != NULL) {
92 		len = sizeof(c->addr);
93 		ec = getnameinfo((struct sockaddr*)&c->addr, len,
94 		    hbuf, sizeof(hbuf),
95 		    sbuf, sizeof(sbuf),
96 		    NI_NUMERICHOST | NI_NUMERICSERV);
97 		if (ec != 0)
98 			fatal("getnameinfo: %s", gai_strerror(ec));
99 	}
100 
101 	if (vasprintf(&fmted, fmt, ap) == -1)
102 		fatal("vasprintf: %s", strerror(errno));
103 
104         if (c == NULL)
105 		ec = asprintf(&s, "internal: %s", fmted);
106 	else
107 		ec = asprintf(&s, "%s:%s %s", hbuf, sbuf, fmted);
108 
109 	if (ec < 0)
110 		fatal("asprintf: %s", strerror(errno));
111 
112 	send_log(s, ec+1);
113 
114 	free(fmted);
115 	free(s);
116 }
117 
118 void
119 log_err(struct client *c, const char *fmt, ...)
120 {
121 	va_list ap;
122 
123 	va_start(ap, fmt);
124 	vlog(LOG_ERR, c, fmt, ap);
125 	va_end(ap);
126 }
127 
128 void
129 log_warn(struct client *c, const char *fmt, ...)
130 {
131 	va_list ap;
132 
133 	va_start(ap, fmt);
134 	vlog(LOG_WARNING, c, fmt, ap);
135 	va_end(ap);
136 }
137 
138 void
139 log_notice(struct client *c, const char *fmt, ...)
140 {
141 	va_list ap;
142 
143 	va_start(ap, fmt);
144 	vlog(LOG_NOTICE, c, fmt, ap);
145 	va_end(ap);
146 }
147 
148 void
149 log_info(struct client *c, const char *fmt, ...)
150 {
151 	va_list ap;
152 
153 	va_start(ap, fmt);
154 	vlog(LOG_INFO, c, fmt, ap);
155 	va_end(ap);
156 }
157 
158 void
159 log_debug(struct client *c, const char *fmt, ...)
160 {
161 	va_list ap;
162 
163 	va_start(ap, fmt);
164 	vlog(LOG_DEBUG, c, fmt, ap);
165 	va_end(ap);
166 }
167 
168 /* strchr, but with a bound */
169 static char *
170 gmid_strnchr(char *s, int c, size_t len)
171 {
172 	size_t i;
173 
174 	for (i = 0; i < len; ++i)
175 		if (s[i] == c)
176 			return &s[i];
177 	return NULL;
178 }
179 
180 void
181 log_request(struct client *c, char *meta, size_t l)
182 {
183 	char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV], b[GEMINI_URL_LEN];
184 	char *t, *fmted;
185 	size_t len;
186 	int ec;
187 
188 	len = sizeof(c->addr);
189 	ec = getnameinfo((struct sockaddr*)&c->addr, len,
190 	    hbuf, sizeof(hbuf),
191 	    sbuf, sizeof(sbuf),
192 	    NI_NUMERICHOST | NI_NUMERICSERV);
193 	if (ec != 0)
194 		fatal("getnameinfo: %s", gai_strerror(ec));
195 
196 	if (c->iri.schema != NULL) {
197 		/* serialize the IRI */
198 		strlcpy(b, c->iri.schema, sizeof(b));
199 		strlcat(b, "://", sizeof(b));
200 
201 		/* log the decoded host name, but if it was invalid
202 		 * use the raw one. */
203 		if (*c->domain != '\0')
204 			strlcat(b, c->domain, sizeof(b));
205 		else
206 			strlcat(b, c->iri.host, sizeof(b));
207 
208 		strlcat(b, "/", sizeof(b));
209 		strlcat(b, c->iri.path, sizeof(b)); /* TODO: sanitize UTF8 */
210 		if (*c->iri.query != '\0') {	    /* TODO: sanitize UTF8 */
211 			strlcat(b, "?", sizeof(b));
212 			strlcat(b, c->iri.query, sizeof(b));
213 		}
214 	} else {
215 		strlcpy(b, c->req, sizeof(b));
216 	}
217 
218 	if ((t = gmid_strnchr(meta, '\r', l)) == NULL)
219 		t = meta + len;
220 
221 	ec = asprintf(&fmted, "%s:%s GET %s %.*s", hbuf, sbuf, b,
222 	    (int)(t-meta), meta);
223 	if (ec < 0)
224 		err(1, "asprintf");
225 	send_log(fmted, ec+1);
226 	free(fmted);
227 }
228 
229 
230 
231 static void
232 handle_log(int fd, short ev, void *d)
233 {
234 	struct imsgbuf	*ibuf = d;
235 	struct imsg	 imsg;
236 	ssize_t		 n, datalen;
237 	char		*msg;
238 
239 	if ((n = imsg_read(ibuf)) == -1) {
240 		if (errno == EAGAIN || errno == EWOULDBLOCK)
241 			return;
242                 err(1, "imsg_read");
243 	}
244 	if (n == 0)
245 		errx(1, "connection lost?");
246 
247 	for (;;) {
248 		if ((n = imsg_get(ibuf, &imsg)) == -1)
249 			err(1, "read error");
250 		if (n == 0)
251 			return;
252 
253 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
254 		msg = imsg.data;
255 		msg[datalen-1] = '\0';
256 
257 		/* ignore imsg.hdr.type for now */
258 		if (conf.foreground)
259 			fprintf(stderr, "%s\n", msg);
260 		else
261 			syslog(LOG_DAEMON, "%s", msg);
262 
263 		imsg_free(&imsg);
264 	}
265 }
266 
267 int
268 logger_main(int fd, struct imsgbuf *ibuf)
269 {
270 	event_init();
271 
272 	event_set(&inlog, fd, EV_READ | EV_PERSIST, &handle_log, ibuf);
273 	event_add(&inlog, NULL);
274 
275 #ifdef __OpenBSD__
276 	if (pledge("stdio", NULL) == -1)
277 		err(1, "pledge");
278 #endif
279 
280 	event_dispatch();
281 
282 	return 0;
283 }