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 
43 static void logger_init(struct privsep *, struct privsep_proc *, void *);
44 static void logger_shutdown(void);
45 static int logger_dispatch_parent(int, struct privsep_proc *, struct imsg *);
46 static int logger_dispatch_server(int, struct privsep_proc *, struct imsg *);
47 
48 static struct privsep_proc procs[] = {
49 	{ "parent",	PROC_PARENT,	logger_dispatch_parent },
50 	{ "server",	PROC_SERVER,	logger_dispatch_server },
51 };
52 
53 void
54 logger(struct privsep *ps, struct privsep_proc *p)
55 {
56 	proc_run(ps, p, procs, nitems(procs), logger_init, NULL);
57 }
58 
59 static void
60 logger_init(struct privsep *ps, struct privsep_proc *p, void *arg)
61 {
62 	p->p_shutdown = logger_shutdown;
63 	sandbox_logger_process();
64 }
65 
66 static void
67 logger_shutdown(void)
68 {
69 	closelog();
70 	if (logfd != -1)
71 		close(logfd);
72 }
73 
74 static int
75 logger_dispatch_parent(int fd, struct privsep_proc *p, struct imsg *imsg)
76 {
77 	switch (imsg->hdr.type) {
78 	case IMSG_LOG_SYSLOG:
79 		if (IMSG_DATA_SIZE(imsg) != sizeof(log_to_syslog))
80 			fatal("corrupted IMSG_LOG_SYSLOG");
81 		memcpy(&log_to_syslog, imsg->data, sizeof(log_to_syslog));
82 		break;
83 	case IMSG_LOG_ACCESS:
84 		if (logfd != -1)
85 			close(logfd);
86 		logfd = -1;
87 
88 		if (imsg->fd != -1)
89 			logfd = imsg->fd;
90 		break;
91 	default:
92 		return -1;
93 	}
94 
95 	return 0;
96 }
97 
98 static int
99 logger_dispatch_server(int fd, struct privsep_proc *p, struct imsg *imsg)
100 {
101 	char *msg;
102 	size_t datalen;
103 
104 	switch (imsg->hdr.type) {
105 	case IMSG_LOG_REQUEST:
106 		msg = imsg->data;
107 		datalen = IMSG_DATA_SIZE(imsg);
108 		if (datalen == 0)
109 			fatal("got invalid IMSG_LOG_REQUEST");
110 		msg[datalen - 1] = '\0';
111 		if (logfd != -1)
112 			dprintf(logfd, "%s\n", msg);
113 		if (log_to_syslog)
114 			syslog(LOG_DAEMON | LOG_NOTICE, "%s", msg);
115 		break;
116 	default:
117 		return -1;
118 	}
119 
120 	return 0;
121 }