xref: /illumos-gate/usr/src/cmd/krb5/kwarn/kwarnd.c (revision 49218d4f8e4d84d1c08aeb267bcf6e451f2056dc)
1 /*
2  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
3  * Use is subject to license terms.
4  */
5 
6 /*
7  * Usermode daemon which is responsible for sending kerberos credentials
8  * expiration warnings to the user, syslog or snmp (eventually), depending
9  * on how it is configured through /etc/krb5/warn.conf.
10  * the code in this file was borrowed from gssd.c
11  */
12 
13 #pragma ident	"%Z%%M%	%I%	%E% SMI"
14 
15 #include <stdio.h>
16 #include <rpc/rpc.h>
17 #include <sys/syslog.h>
18 #include <sys/termios.h>
19 #include <unistd.h>
20 #include <sys/resource.h>
21 #include <sys/utsname.h>
22 #include <sys/systeminfo.h>
23 #include <stdlib.h>
24 #include <stropts.h>
25 #include <fcntl.h>
26 #include <strings.h>
27 #include <syslog.h>
28 #include <thread.h>
29 #include "kwarnd.h"
30 
31 #define	MAXTHREADS 64
32 
33 int kwarnd_debug = 0;		/* enable debugging printfs */
34 
35 extern void kwarnprog_1(struct svc_req *, register SVCXPRT *);
36 static void usage(void);
37 static void detachfromtty(void);
38 extern int svc_create_local_service(void (*) (),
39 					u_long, u_long, char *, char *);
40 extern void kwarnd_check_warning_list(void);
41 extern bool_t loadConfigFile(void);
42 
43 /* following declarations needed in rpcgen-generated code */
44 int _rpcpmstart = 0;		/* Started by a port monitor ? */
45 int _rpcfdtype;			/* Whether Stream or Datagram ? */
46 int _rpcsvcdirty;		/* Still serving ? */
47 
48 int
49 main(argc, argv)
50 int argc;
51 char **argv;
52 {
53 	register SVCXPRT *transp;
54 	extern int optind;
55 	int c;
56 	char mname[FMNAMESZ + 1];
57 	int rpc_svc_mode = RPC_SVC_MT_AUTO;
58 	extern int _getuid();
59 
60 
61 	/* set locale and domain for internationalization */
62 	setlocale(LC_ALL, "");
63 
64 #if !defined(TEXT_DOMAIN)
65 #define TEXT_DOMAIN "SYS_TEST"
66 #endif
67 
68 	textdomain(TEXT_DOMAIN);
69 
70 	/*
71 	 * take special note that "_getuid()" is called here. This is necessary
72 	 * since we must fake out the mechanism libraries calls to getuid()
73 	 * with a special routine that is provided as part of kwarnd. However,
74 	 * the call below MUST call the real getuid() to ensure it is running
75 	 * as root.
76 	*/
77 
78 #ifdef DEBUG
79 	(void) setuid(0);		/* DEBUG: set ruid to root */
80 #endif /* DEBUG */
81 	if (_getuid()) {
82 		(void) fprintf(stderr,
83 				gettext("[%s] must be run as root\n"), argv[0]);
84 #ifdef DEBUG
85 		(void) fprintf(stderr, gettext(" warning only\n"));
86 #else /* !DEBUG */
87 		exit(1);
88 #endif /* DEBUG */
89 	}
90 
91 	while ((c = getopt(argc, argv, "d")) != -1)
92 		switch (c) {
93 		    case 'd':
94 			/* turn on debugging */
95 			kwarnd_debug = 1;
96 			break;
97 		    default:
98 			usage();
99 		}
100 
101 	if (optind != argc) {
102 		usage();
103 	}
104 
105 	/*
106 	 * Started by inetd if name of module just below stream
107 	 * head is either a sockmod or timod.
108 	 */
109 	if (!ioctl(0, I_LOOK, mname) &&
110 		((strcmp(mname, "sockmod") == 0) ||
111 			(strcmp(mname, "timod") == 0))) {
112 
113 		char *netid;
114 		struct netconfig *nconf;
115 
116 		openlog("kwarnd", LOG_PID, LOG_DAEMON);
117 
118 		if ((netid = getenv("NLSPROVIDER")) ==  NULL) {
119 			netid = "ticotsord";
120 		}
121 
122 		if ((nconf = getnetconfigent(netid)) == NULL) {
123 			syslog(LOG_ERR, gettext("cannot get transport info"));
124 			exit(1);
125 		}
126 
127 		if (strcmp(mname, "sockmod") == 0) {
128 			if (ioctl(0, I_POP, 0) || ioctl(0, I_PUSH, "timod")) {
129 				syslog(LOG_ERR,
130 					gettext("could not get the "
131 						"right module"));
132 				exit(1);
133 			}
134 		}
135 
136 		/* XXX - is nconf even needed here? */
137 		if ((transp = svc_tli_create(0, nconf, NULL, 0, 0)) == NULL) {
138 			syslog(LOG_ERR, gettext("cannot create server handle"));
139 			exit(1);
140 		}
141 
142 		/*
143 		 * We use a NULL nconf because KWARNPROG has already been
144 		 * registered with rpcbind.
145 		 */
146 		if (!svc_reg(transp, KWARNPROG, KWARNVERS, kwarnprog_1, NULL)) {
147 			syslog(LOG_ERR,
148 				gettext("unable to register "
149 					"(KWARNPROG, KWARNVERS)"));
150 			exit(1);
151 		}
152 
153 		if (nconf)
154 			freenetconfigent(nconf);
155 	} else {
156 
157 		if (!kwarnd_debug)
158 			detachfromtty();
159 
160 		openlog("kwarnd", LOG_PID, LOG_DAEMON);
161 
162 		if (svc_create_local_service(kwarnprog_1, KWARNPROG, KWARNVERS,
163 		    "netpath", "kwarnd") == 0) {
164 			syslog(LOG_ERR, gettext("unable to create service"));
165 			exit(1);
166 		}
167 	}
168 
169 
170 	if (kwarnd_debug) {
171 		fprintf(stderr,
172 		    gettext("kwarnd start: \n"));
173 	}
174 
175  	(void) signal(SIGCHLD, SIG_IGN);
176 
177 	if (thr_create(NULL, 0,
178 			(void *(*)(void *))kwarnd_check_warning_list, NULL,
179 			THR_DETACHED | THR_DAEMON | THR_NEW_LWP,
180 			NULL)) {
181 		syslog(LOG_ERR,
182 			gettext("unable to create cache_cleanup thread"));
183 		exit(1);
184 	}
185 
186 	if (!loadConfigFile()) {
187 		syslog(LOG_ERR, gettext("could not read config file\n"));
188 		exit(1);
189 	}
190 
191 	if (!rpc_control(RPC_SVC_MTMODE_SET, &rpc_svc_mode)) {
192 		syslog(LOG_ERR, gettext("unable to set automatic MT mode"));
193 		exit(1);
194 	}
195 
196 	svc_run();
197 	abort();
198 	/*NOTREACHED*/
199 #ifdef	lint
200 	return (1);
201 #endif
202 }
203 
204 static void
205 usage(void)
206 {
207 	(void) fprintf(stderr, gettext("usage: kwarnd [-d]\n"));
208 	exit(1);
209 }
210 
211 
212 /*
213  * detach from tty
214  */
215 static void
216 detachfromtty(void)
217 {
218 	switch (fork()) {
219 	case -1:
220 		perror(gettext("kwarnd: can not fork"));
221 		exit(1);
222 		/*NOTREACHED*/
223 	case 0:
224 		break;
225 	default:
226 		exit(0);
227 	}
228 
229 	/*
230 	 * Close existing file descriptors, open "/dev/null" as
231 	 * standard input, output, and error, and detach from
232 	 * controlling terminal.
233 	 */
234 	closefrom(0);
235 	(void) open("/dev/null", O_RDONLY);
236 	(void) open("/dev/null", O_WRONLY);
237 	(void) dup(1);
238 	(void) setsid();
239 }
240 
241 /*ARGSUSED*/
242 int
243 kwarnprog_1_freeresult(SVCXPRT *transport, xdrproc_t xdr_res, caddr_t res)
244 {
245 	xdr_free(xdr_res, res);
246 	return (1);
247 }
248