xref: /openbsd/libexec/rpc.rstatd/rstatd.c (revision 76d0caae)
1 /*	$OpenBSD: rstatd.c,v 1.30 2019/06/28 13:32:53 deraadt 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 /* ARGSUSED */
55 static void
56 getsig(int signo)
57 {
58 	gotsig = 1;
59 }
60 
61 
62 int
63 main(int argc, char *argv[])
64 {
65 	int sock = 0, proto = 0;
66 	socklen_t fromlen;
67 	struct passwd *pw;
68 	struct sockaddr_storage from;
69 	SVCXPRT *transp;
70 
71 	openlog("rpc.rstatd", LOG_NDELAY|LOG_CONS|LOG_PID, LOG_DAEMON);
72 
73 	if ((pw = getpwnam("_rstatd")) == NULL) {
74 		syslog(LOG_ERR, "no such user _rstatd");
75 		exit(1);
76 	}
77 	if (chroot("/var/empty") == -1) {
78 		syslog(LOG_ERR, "cannot chdir to /var/empty.");
79 		exit(1);
80 	}
81 	chdir("/");
82 
83 	setgroups(1, &pw->pw_gid);
84 	setegid(pw->pw_gid);
85 	setgid(pw->pw_gid);
86 	seteuid(pw->pw_uid);
87 	setuid(pw->pw_uid);
88 
89 	if (argc == 2)
90 		closedown = strtonum(argv[1], 1, INT_MAX, NULL);
91 	if (closedown == 0)
92 		closedown = 20;
93 
94 	/*
95 	 * See if inetd started us
96 	 */
97 	fromlen = sizeof(from);
98 	if (getsockname(0, (struct sockaddr *)&from, &fromlen) == -1) {
99 		from_inetd = 0;
100 		sock = RPC_ANYSOCK;
101 		proto = IPPROTO_UDP;
102 	}
103 
104 	if (!from_inetd) {
105 		daemon(0, 0);
106 
107 		(void)pmap_unset(RSTATPROG, RSTATVERS_TIME);
108 		(void)pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
109 		(void)pmap_unset(RSTATPROG, RSTATVERS_ORIG);
110 
111 		(void) signal(SIGINT, getsig);
112 		(void) signal(SIGTERM, getsig);
113 		(void) signal(SIGHUP, getsig);
114 	}
115 
116 	transp = svcudp_create(sock);
117 	if (transp == NULL) {
118 		syslog(LOG_ERR, "cannot create udp service.");
119 		exit(1);
120 	}
121 	if (!svc_register(transp, RSTATPROG, RSTATVERS_TIME, rstat_service, proto)) {
122 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_TIME, udp).");
123 		exit(1);
124 	}
125 	if (!svc_register(transp, RSTATPROG, RSTATVERS_SWTCH, rstat_service, proto)) {
126 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_SWTCH, udp).");
127 		exit(1);
128 	}
129 	if (!svc_register(transp, RSTATPROG, RSTATVERS_ORIG, rstat_service, proto)) {
130 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_ORIG, udp).");
131 		exit(1);
132 	}
133 
134 	my_svc_run();
135 	syslog(LOG_ERR, "svc_run returned");
136 	exit(1);
137 }
138 
139 void
140 my_svc_run(void)
141 {
142 	extern volatile sig_atomic_t wantupdatestat;
143 	extern void updatestat(void);
144 	struct pollfd *pfd = NULL, *newp;
145 	int nready, saved_max_pollfd = 0;
146 
147 	for (;;) {
148 		if (wantupdatestat) {
149 			wantupdatestat = 0;
150 			updatestat();
151 		}
152 		if (gotsig) {
153 			(void) pmap_unset(RSTATPROG, RSTATVERS_TIME);
154 			(void) pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
155 			(void) pmap_unset(RSTATPROG, RSTATVERS_ORIG);
156 			exit(0);
157 		}
158 		if (svc_max_pollfd > saved_max_pollfd) {
159 			newp = reallocarray(pfd, svc_max_pollfd, sizeof(*pfd));
160 			if (newp == NULL) {
161 				free(pfd);
162 				perror("svc_run: - realloc failed");
163 				return;
164 			}
165 			pfd = newp;
166 			saved_max_pollfd = svc_max_pollfd;
167 		}
168 		memcpy(pfd, svc_pollfd, svc_max_pollfd * sizeof(*pfd));
169 
170 		nready = poll(pfd, svc_max_pollfd, INFTIM);
171 		switch (nready) {
172 		case -1:
173 			if (errno == EINTR)
174 				continue;
175 			perror("svc_run: - poll failed");
176 			free(pfd);
177 			return;
178 		case 0:
179 			continue;
180 		default:
181 			svc_getreq_poll(pfd, nready);
182 		}
183 	}
184 }
185