xref: /openbsd/libexec/rpc.rstatd/rstatd.c (revision 5b133f3f)
1 /*	$OpenBSD: rstatd.c,v 1.31 2023/03/08 04:43:05 guenther Exp $	*/
2 
3 /*-
4  * Copyright (c) 1993, John Brezak
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. The name of the author may not be used to endorse or promote products
16  *    derived from this software without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  */
30 
31 #include <sys/types.h>
32 #include <sys/socket.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 #include <limits.h>
38 #include <signal.h>
39 #include <pwd.h>
40 #include <syslog.h>
41 #include <errno.h>
42 #include <rpc/rpc.h>
43 #include <rpcsvc/rstat.h>
44 
45 extern void rstat_service(struct svc_req *, SVCXPRT *);
46 
47 void my_svc_run(void);
48 
49 int from_inetd = 1;	/* started from inetd ? */
50 int closedown = 20;	/* how long to wait before going dormant */
51 
52 volatile sig_atomic_t gotsig;
53 
54 static void
getsig(int signo)55 getsig(int signo)
56 {
57 	gotsig = 1;
58 }
59 
60 
61 int
main(int argc,char * argv[])62 main(int argc, char *argv[])
63 {
64 	int sock = 0, proto = 0;
65 	socklen_t fromlen;
66 	struct passwd *pw;
67 	struct sockaddr_storage from;
68 	SVCXPRT *transp;
69 
70 	openlog("rpc.rstatd", LOG_NDELAY|LOG_CONS|LOG_PID, LOG_DAEMON);
71 
72 	if ((pw = getpwnam("_rstatd")) == NULL) {
73 		syslog(LOG_ERR, "no such user _rstatd");
74 		exit(1);
75 	}
76 	if (chroot("/var/empty") == -1) {
77 		syslog(LOG_ERR, "cannot chdir to /var/empty.");
78 		exit(1);
79 	}
80 	chdir("/");
81 
82 	setgroups(1, &pw->pw_gid);
83 	setegid(pw->pw_gid);
84 	setgid(pw->pw_gid);
85 	seteuid(pw->pw_uid);
86 	setuid(pw->pw_uid);
87 
88 	if (argc == 2)
89 		closedown = strtonum(argv[1], 1, INT_MAX, NULL);
90 	if (closedown == 0)
91 		closedown = 20;
92 
93 	/*
94 	 * See if inetd started us
95 	 */
96 	fromlen = sizeof(from);
97 	if (getsockname(0, (struct sockaddr *)&from, &fromlen) == -1) {
98 		from_inetd = 0;
99 		sock = RPC_ANYSOCK;
100 		proto = IPPROTO_UDP;
101 	}
102 
103 	if (!from_inetd) {
104 		daemon(0, 0);
105 
106 		(void)pmap_unset(RSTATPROG, RSTATVERS_TIME);
107 		(void)pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
108 		(void)pmap_unset(RSTATPROG, RSTATVERS_ORIG);
109 
110 		(void) signal(SIGINT, getsig);
111 		(void) signal(SIGTERM, getsig);
112 		(void) signal(SIGHUP, getsig);
113 	}
114 
115 	transp = svcudp_create(sock);
116 	if (transp == NULL) {
117 		syslog(LOG_ERR, "cannot create udp service.");
118 		exit(1);
119 	}
120 	if (!svc_register(transp, RSTATPROG, RSTATVERS_TIME, rstat_service, proto)) {
121 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_TIME, udp).");
122 		exit(1);
123 	}
124 	if (!svc_register(transp, RSTATPROG, RSTATVERS_SWTCH, rstat_service, proto)) {
125 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_SWTCH, udp).");
126 		exit(1);
127 	}
128 	if (!svc_register(transp, RSTATPROG, RSTATVERS_ORIG, rstat_service, proto)) {
129 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_ORIG, udp).");
130 		exit(1);
131 	}
132 
133 	my_svc_run();
134 	syslog(LOG_ERR, "svc_run returned");
135 	exit(1);
136 }
137 
138 void
my_svc_run(void)139 my_svc_run(void)
140 {
141 	extern volatile sig_atomic_t wantupdatestat;
142 	extern void updatestat(void);
143 	struct pollfd *pfd = NULL, *newp;
144 	int nready, saved_max_pollfd = 0;
145 
146 	for (;;) {
147 		if (wantupdatestat) {
148 			wantupdatestat = 0;
149 			updatestat();
150 		}
151 		if (gotsig) {
152 			(void) pmap_unset(RSTATPROG, RSTATVERS_TIME);
153 			(void) pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
154 			(void) pmap_unset(RSTATPROG, RSTATVERS_ORIG);
155 			exit(0);
156 		}
157 		if (svc_max_pollfd > saved_max_pollfd) {
158 			newp = reallocarray(pfd, svc_max_pollfd, sizeof(*pfd));
159 			if (newp == NULL) {
160 				free(pfd);
161 				perror("svc_run: - realloc failed");
162 				return;
163 			}
164 			pfd = newp;
165 			saved_max_pollfd = svc_max_pollfd;
166 		}
167 		memcpy(pfd, svc_pollfd, svc_max_pollfd * sizeof(*pfd));
168 
169 		nready = poll(pfd, svc_max_pollfd, INFTIM);
170 		switch (nready) {
171 		case -1:
172 			if (errno == EINTR)
173 				continue;
174 			perror("svc_run: - poll failed");
175 			free(pfd);
176 			return;
177 		case 0:
178 			continue;
179 		default:
180 			svc_getreq_poll(pfd, nready);
181 		}
182 	}
183 }
184