xref: /illumos-gate/usr/src/cmd/krb5/kwarn/kwarnd.c (revision 3db86aab)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 /*
22  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * Usermode daemon which is responsible for sending kerberos credentials
28  * expiration warnings to the user, syslog or snmp (eventually), depending
29  * on how it is configured through /etc/krb5/warn.conf.
30  * the code in this file was borrowed from gssd.c
31  */
32 
33 #pragma ident	"%Z%%M%	%I%	%E% SMI"
34 
35 #include <stdio.h>
36 #include <rpc/rpc.h>
37 #include <sys/syslog.h>
38 #include <sys/termios.h>
39 #include <unistd.h>
40 #include <sys/resource.h>
41 #include <sys/utsname.h>
42 #include <sys/systeminfo.h>
43 #include <stdlib.h>
44 #include <stropts.h>
45 #include <fcntl.h>
46 #include <strings.h>
47 #include <syslog.h>
48 #include <thread.h>
49 #include <netdb.h>
50 #include <libgen.h>
51 #include "kwarnd.h"
52 
53 #define	MAXTHREADS 64
54 
55 int kwarnd_debug = 0;		/* enable debugging printfs */
56 
57 extern void kwarnprog_1(struct svc_req *, register SVCXPRT *);
58 static void usage(void);
59 static void detachfromtty(void);
60 extern int svc_create_local_service(void (*) (),
61 					ulong_t, ulong_t, char *, char *);
62 extern void kwarnd_check_warning_list(void);
63 extern bool_t loadConfigFile(void);
64 
65 /* following declarations needed in rpcgen-generated code */
66 int _rpcpmstart = 0;		/* Started by a port monitor ? */
67 int _rpcfdtype;			/* Whether Stream or Datagram ? */
68 int _rpcsvcdirty;		/* Still serving ? */
69 
70 char myhostname[MAXHOSTNAMELEN] = {0};
71 char progname[MAXNAMELEN] = {0};
72 
73 
74 int
75 main(argc, argv)
76 int argc;
77 char **argv;
78 {
79 	register SVCXPRT *transp;
80 	extern int optind;
81 	int c;
82 	char mname[FMNAMESZ + 1];
83 	int rpc_svc_mode = RPC_SVC_MT_AUTO;
84 	extern int _getuid();
85 
86 
87 	/* set locale and domain for internationalization */
88 	setlocale(LC_ALL, "");
89 
90 #if !defined(TEXT_DOMAIN)
91 #define	TEXT_DOMAIN "SYS_TEST"
92 #endif
93 
94 	textdomain(TEXT_DOMAIN);
95 
96 	(void) strlcpy(progname, basename(argv[0]), sizeof (progname));
97 
98 	/*
99 	 * take special note that "_getuid()" is called here. This is necessary
100 	 * since we must fake out the mechanism libraries calls to getuid()
101 	 * with a special routine that is provided as part of kwarnd. However,
102 	 * the call below MUST call the real getuid() to ensure it is running
103 	 * as root.
104 	 */
105 
106 #ifdef DEBUG
107 	(void) setuid(0);		/* DEBUG: set ruid to root */
108 #endif /* DEBUG */
109 	if (_getuid()) {
110 		(void) fprintf(stderr,
111 				gettext("[%s] must be run as root\n"), argv[0]);
112 #ifdef DEBUG
113 		(void) fprintf(stderr, gettext(" warning only\n"));
114 #else /* !DEBUG */
115 		exit(1);
116 #endif /* DEBUG */
117 	}
118 
119 	while ((c = getopt(argc, argv, "d")) != -1)
120 		switch (c) {
121 		    case 'd':
122 			/* turn on debugging */
123 			kwarnd_debug = 1;
124 			break;
125 		    default:
126 			usage();
127 		}
128 
129 	if (optind != argc) {
130 		usage();
131 	}
132 
133 	(void) gethostname(myhostname, sizeof (myhostname));
134 
135 	/*
136 	 * Started by inetd if name of module just below stream
137 	 * head is either a sockmod or timod.
138 	 */
139 	if (!ioctl(0, I_LOOK, mname) &&
140 		((strcmp(mname, "sockmod") == 0) ||
141 			(strcmp(mname, "timod") == 0))) {
142 
143 		char *netid;
144 		struct netconfig *nconf;
145 
146 		openlog("kwarnd", LOG_PID, LOG_DAEMON);
147 
148 		if ((netid = getenv("NLSPROVIDER")) ==  NULL) {
149 			netid = "ticotsord";
150 		}
151 
152 		if ((nconf = getnetconfigent(netid)) == NULL) {
153 			syslog(LOG_ERR, gettext("cannot get transport info"));
154 			exit(1);
155 		}
156 
157 		if (strcmp(mname, "sockmod") == 0) {
158 			if (ioctl(0, I_POP, 0) || ioctl(0, I_PUSH, "timod")) {
159 				syslog(LOG_ERR,
160 					gettext("could not get the "
161 						"right module"));
162 				exit(1);
163 			}
164 		}
165 
166 		/* XXX - is nconf even needed here? */
167 		if ((transp = svc_tli_create(0, nconf, NULL, 0, 0)) == NULL) {
168 			syslog(LOG_ERR, gettext("cannot create server handle"));
169 			exit(1);
170 		}
171 
172 		/*
173 		 * We use a NULL nconf because KWARNPROG has already been
174 		 * registered with rpcbind.
175 		 */
176 		if (!svc_reg(transp, KWARNPROG, KWARNVERS, kwarnprog_1, NULL)) {
177 			syslog(LOG_ERR,
178 				gettext("unable to register "
179 					"(KWARNPROG, KWARNVERS)"));
180 			exit(1);
181 		}
182 
183 		if (nconf)
184 			freenetconfigent(nconf);
185 	} else {
186 
187 		if (!kwarnd_debug)
188 			detachfromtty();
189 
190 		openlog("kwarnd", LOG_PID, LOG_DAEMON);
191 
192 		if (svc_create_local_service(kwarnprog_1, KWARNPROG, KWARNVERS,
193 		    "netpath", "kwarnd") == 0) {
194 			syslog(LOG_ERR, gettext("unable to create service"));
195 			exit(1);
196 		}
197 	}
198 
199 
200 	if (kwarnd_debug) {
201 		fprintf(stderr,
202 		    gettext("kwarnd start: \n"));
203 	}
204 
205 	(void) signal(SIGCHLD, SIG_IGN);
206 
207 	if (thr_create(NULL, 0,
208 			(void *(*)(void *))kwarnd_check_warning_list, NULL,
209 			THR_DETACHED | THR_DAEMON | THR_NEW_LWP,
210 			NULL)) {
211 		syslog(LOG_ERR,
212 			gettext("unable to create cache_cleanup thread"));
213 		exit(1);
214 	}
215 
216 	if (!loadConfigFile()) {
217 		syslog(LOG_ERR, gettext("could not read config file\n"));
218 		exit(1);
219 	}
220 
221 	if (!rpc_control(RPC_SVC_MTMODE_SET, &rpc_svc_mode)) {
222 		syslog(LOG_ERR, gettext("unable to set automatic MT mode"));
223 		exit(1);
224 	}
225 
226 	svc_run();
227 	abort();
228 	/*NOTREACHED*/
229 #ifdef	lint
230 	return (1);
231 #endif
232 }
233 
234 static void
235 usage(void)
236 {
237 	(void) fprintf(stderr, gettext("usage: %s [-d]\n"), progname);
238 	exit(1);
239 }
240 
241 
242 /*
243  * detach from tty
244  */
245 static void
246 detachfromtty(void)
247 {
248 	switch (fork()) {
249 	case -1:
250 		perror(gettext("kwarnd: can not fork"));
251 		exit(1);
252 		/*NOTREACHED*/
253 	case 0:
254 		break;
255 	default:
256 		exit(0);
257 	}
258 
259 	/*
260 	 * Close existing file descriptors, open "/dev/null" as
261 	 * standard input, output, and error, and detach from
262 	 * controlling terminal.
263 	 */
264 	closefrom(0);
265 	(void) open("/dev/null", O_RDONLY);
266 	(void) open("/dev/null", O_WRONLY);
267 	(void) dup(1);
268 	(void) setsid();
269 }
270 
271 /*ARGSUSED*/
272 int
273 kwarnprog_1_freeresult(SVCXPRT *transport, xdrproc_t xdr_res, caddr_t res)
274 {
275 	xdr_free(xdr_res, res);
276 	return (1);
277 }
278