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