1 /*
2  * Copyright (c) 2021, 2023 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 <poll.h>
27 #include <stdarg.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <syslog.h>
31 #include <time.h>
32 
33 #include "log.h"
34 #include "proc.h"
35 
36 #ifndef nitems
37 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
38 #endif
39 
40 static int logfd = -1;
41 static int log_to_syslog = 1;
42 static int facility = LOG_DAEMON;
43 
44 static void logger_init(struct privsep *, struct privsep_proc *, void *);
45 static void logger_shutdown(void);
46 static int logger_dispatch_parent(int, struct privsep_proc *, struct imsg *);
47 static int logger_dispatch_server(int, struct privsep_proc *, struct imsg *);
48 
49 static struct privsep_proc procs[] = {
50 	{ "parent",	PROC_PARENT,	logger_dispatch_parent },
51 	{ "server",	PROC_SERVER,	logger_dispatch_server },
52 };
53 
54 void
55 logger(struct privsep *ps, struct privsep_proc *p)
56 {
57 	proc_run(ps, p, procs, nitems(procs), logger_init, NULL);
58 }
59 
60 static void
61 logger_init(struct privsep *ps, struct privsep_proc *p, void *arg)
62 {
63 	p->p_shutdown = logger_shutdown;
64 
65 	openlog(getprogname(), LOG_NDELAY, LOG_DAEMON);
66 	tzset();
67 
68 	sandbox_logger_process();
69 }
70 
71 static void
72 logger_shutdown(void)
73 {
74 	closelog();
75 	if (logfd != -1)
76 		close(logfd);
77 }
78 
79 static int
80 logger_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg)
81 {
82 	switch (imsg->hdr.type) {
83 	case IMSG_LOG_FACILITY:
84 		if (IMSG_DATA_SIZE(imsg) != sizeof(facility))
85 			fatal("corrupted IMSG_LOG_SYSLOG");
86 		memcpy(&facility, imsg->data, sizeof(facility));
87 		break;
88 	case IMSG_LOG_SYSLOG:
89 		if (IMSG_DATA_SIZE(imsg) != sizeof(log_to_syslog))
90 			fatal("corrupted IMSG_LOG_SYSLOG");
91 		memcpy(&log_to_syslog, imsg->data, sizeof(log_to_syslog));
92 		break;
93 	case IMSG_LOG_ACCESS:
94 		if (logfd != -1)
95 			close(logfd);
96 		logfd = -1;
97 
98 		if (imsg->fd != -1)
99 			logfd = imsg->fd;
100 		break;
101 	default:
102 		return -1;
103 	}
104 
105 	return 0;
106 }
107 
108 static int
109 logger_dispatch_server(int fd, struct privsep_proc *p, struct imsg *imsg)
110 {
111 	char *msg;
112 	size_t datalen;
113 
114 	switch (imsg->hdr.type) {
115 	case IMSG_LOG_REQUEST:
116 		msg = imsg->data;
117 		datalen = IMSG_DATA_SIZE(imsg);
118 		if (datalen == 0)
119 			fatal("got invalid IMSG_LOG_REQUEST");
120 		msg[datalen - 1] = '\0';
121 		if (logfd != -1)
122 			dprintf(logfd, "%s\n", msg);
123 		if (log_to_syslog)
124 			syslog(facility | LOG_NOTICE, "%s", msg);
125 		break;
126 	default:
127 		return -1;
128 	}
129 
130 	return 0;
131 }