xref: /openbsd/libexec/rpc.rstatd/rstatd.c (revision cecf84d4)
1 /*	$OpenBSD: rstatd.c,v 1.27 2015/04/18 18:28:37 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 	const char *errstr;
70 	SVCXPRT *transp;
71 
72 	openlog("rpc.rstatd", LOG_NDELAY|LOG_CONS|LOG_PID, LOG_DAEMON);
73 
74 	if ((pw = getpwnam("_rstatd")) == NULL) {
75 		syslog(LOG_ERR, "no such user _rstatd");
76 		exit(1);
77 	}
78 	if (chroot("/var/empty") == -1) {
79 		syslog(LOG_ERR, "cannot chdir to /var/empty.");
80 		exit(1);
81 	}
82 	chdir("/");
83 
84 	if (pw) {
85 		setgroups(1, &pw->pw_gid);
86 		setegid(pw->pw_gid);
87 		setgid(pw->pw_gid);
88 		seteuid(pw->pw_uid);
89 		setuid(pw->pw_uid);
90 	}
91 
92 	if (argc == 2)
93 		closedown = strtonum(argv[1], 1, INT_MAX, NULL);
94 	if (closedown == 0)
95 		closedown = 20;
96 
97 	/*
98 	 * See if inetd started us
99 	 */
100 	fromlen = sizeof(from);
101 	if (getsockname(0, (struct sockaddr *)&from, &fromlen) < 0) {
102 		from_inetd = 0;
103 		sock = RPC_ANYSOCK;
104 		proto = IPPROTO_UDP;
105 	}
106 
107 	if (!from_inetd) {
108 		daemon(0, 0);
109 
110 		(void)pmap_unset(RSTATPROG, RSTATVERS_TIME);
111 		(void)pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
112 		(void)pmap_unset(RSTATPROG, RSTATVERS_ORIG);
113 
114 		(void) signal(SIGINT, getsig);
115 		(void) signal(SIGTERM, getsig);
116 		(void) signal(SIGHUP, getsig);
117 	}
118 
119 	transp = svcudp_create(sock);
120 	if (transp == NULL) {
121 		syslog(LOG_ERR, "cannot create udp service.");
122 		exit(1);
123 	}
124 	if (!svc_register(transp, RSTATPROG, RSTATVERS_TIME, rstat_service, proto)) {
125 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_TIME, udp).");
126 		exit(1);
127 	}
128 	if (!svc_register(transp, RSTATPROG, RSTATVERS_SWTCH, rstat_service, proto)) {
129 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_SWTCH, udp).");
130 		exit(1);
131 	}
132 	if (!svc_register(transp, RSTATPROG, RSTATVERS_ORIG, rstat_service, proto)) {
133 		syslog(LOG_ERR, "unable to register (RSTATPROG, RSTATVERS_ORIG, udp).");
134 		exit(1);
135 	}
136 
137 	my_svc_run();
138 	syslog(LOG_ERR, "svc_run returned");
139 	exit(1);
140 }
141 
142 void
143 my_svc_run(void)
144 {
145 	extern volatile sig_atomic_t wantupdatestat;
146 	extern void updatestat(void);
147 	struct pollfd *pfd = NULL, *newp;
148 	int nready, saved_max_pollfd = 0;
149 
150 	for (;;) {
151 		if (wantupdatestat) {
152 			wantupdatestat = 0;
153 			updatestat();
154 		}
155 		if (gotsig) {
156 			(void) pmap_unset(RSTATPROG, RSTATVERS_TIME);
157 			(void) pmap_unset(RSTATPROG, RSTATVERS_SWTCH);
158 			(void) pmap_unset(RSTATPROG, RSTATVERS_ORIG);
159 			exit(0);
160 		}
161 		if (svc_max_pollfd > saved_max_pollfd) {
162 			newp = reallocarray(pfd, svc_max_pollfd, sizeof(*pfd));
163 			if (newp == NULL) {
164 				free(pfd);
165 				perror("svc_run: - realloc failed");
166 				return;
167 			}
168 			pfd = newp;
169 			saved_max_pollfd = svc_max_pollfd;
170 		}
171 		memcpy(pfd, svc_pollfd, svc_max_pollfd * sizeof(*pfd));
172 
173 		nready = poll(pfd, svc_max_pollfd, INFTIM);
174 		switch (nready) {
175 		case -1:
176 			if (errno == EINTR)
177 				continue;
178 			perror("svc_run: - poll failed");
179 			free(pfd);
180 			return;
181 		case 0:
182 			continue;
183 		default:
184 			svc_getreq_poll(pfd, nready);
185 		}
186 	}
187 }
188