xref: /illumos-gate/usr/src/cmd/gss/gssd/gssd.c (revision bbf215553c7233fbab8a0afdf1fac74c44781867)
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 2007 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 /*
27  * Usermode daemon which assists the kernel when handling gssapi calls.
28  * It is gssd that actually implements all gssapi calls.
29  * Some calls, such as gss_sign, are implemented in the kernel on a per
30  * mechanism basis.
31  */
32 
33 #include <stdio.h>
34 #include <rpc/rpc.h>
35 #include <rpc/rpc_com.h>
36 #include <sys/syslog.h>
37 #include <sys/termios.h>
38 #include <unistd.h>
39 #include <sys/utsname.h>
40 #include <sys/systeminfo.h>
41 #include <stdlib.h>
42 #include <stropts.h>
43 #include <fcntl.h>
44 #include <strings.h>
45 #include <signal.h>
46 #include <syslog.h>
47 #include "gssd.h"
48 
49 int gssd_debug = 0;		/* enable debugging printfs */
50 extern void gsscred_set_options(void);
51 
52 void gssprog_1();
53 void gssd_setup(char *);
54 static void usage(void);
55 static void daemonize_start();
56 static void daemonize_ready(unsigned char status);
57 extern int  svc_create_local_service();
58 
59 /* following declarations needed in rpcgen-generated code */
60 int _rpcpmstart = 0;		/* Started by a port monitor ? */
61 int _rpcfdtype;			/* Whether Stream or Datagram ? */
62 int _rpcsvcdirty;		/* Still serving ? */
63 mutex_t _svcstate_lock = ERRORCHECKMUTEX;
64 
65 static void
66 /* LINTED */
catch_hup(int sig_num)67 catch_hup(int sig_num)
68 {
69 	sigset_t mask_set;  /* used to set a signal masking set. */
70 	sigset_t old_set;   /* used to store the old mask set.   */
71 
72 	/* re-set the signal handler again to catch_hup, for next time */
73 	(void) signal(SIGHUP, catch_hup);
74 	/* mask any further signals while we're inside the handler. */
75 	(void) sigfillset(&mask_set);
76 	(void) sigprocmask(SIG_SETMASK, &mask_set, &old_set);
77 
78 	gsscred_set_options();
79 
80 	/* let admin know the sighup was caught and conf file re-read */
81 	syslog(LOG_INFO,
82 	    "catch_hup: read gsscred.conf opts");
83 	if (gssd_debug)
84 		(void) fprintf(stderr, "catch_hup: read gsscred.conf opts");
85 
86 	(void) sigprocmask(SIG_SETMASK, &old_set, NULL);
87 }
88 
89 
90 int
main(int argc,char ** argv)91 main(int argc, char **argv)
92 {
93 	register SVCXPRT *transp;
94 	int maxrecsz = RPC_MAXDATASIZE;
95 	extern int optind;
96 	int c;
97 	char mname[FMNAMESZ + 1];
98 
99 	/* set locale and domain for internationalization */
100 	setlocale(LC_ALL, "");
101 	textdomain(TEXT_DOMAIN);
102 
103 	/*
104 	 * Take special note that "getuid()" is called here.  This call is used
105 	 * rather than app_krb5_user_uid(), to ensure gssd(8) is running as
106 	 * root.
107 	 */
108 #ifdef DEBUG
109 	(void) setuid(0);		/* DEBUG: set ruid to root */
110 #endif /* DEBUG */
111 	if (getuid()) {
112 		(void) fprintf(stderr,
113 		    gettext("[%s] must be run as root\n"), argv[0]);
114 #ifdef DEBUG
115 		(void) fprintf(stderr, gettext(" warning only\n"));
116 #else /* DEBUG */
117 		exit(1);
118 #endif /* DEBUG */
119 	}
120 
121 	gssd_setup(argv[0]);
122 
123 	while ((c = getopt(argc, argv, "d")) != -1)
124 		switch (c) {
125 		case 'd':
126 			/* turn on debugging */
127 			gssd_debug = 1;
128 			break;
129 		default:
130 			usage();
131 		}
132 
133 	if (optind != argc) {
134 		usage();
135 	}
136 
137 	gsscred_set_options();
138 	(void) signal(SIGHUP, catch_hup);
139 
140 	/*
141 	 * Started by inetd if name of module just below stream
142 	 * head is either a sockmod or timod.
143 	 */
144 	if (!ioctl(0, I_LOOK, mname) && ((strcmp(mname, "sockmod") == 0) ||
145 	    (strcmp(mname, "timod") == 0))) {
146 
147 		char *netid;
148 		struct netconfig *nconf;
149 
150 		openlog("gssd", LOG_PID, LOG_DAEMON);
151 
152 		if ((netid = getenv("NLSPROVIDER")) ==  NULL) {
153 			netid = "ticotsord";
154 		}
155 
156 		if ((nconf = getnetconfigent(netid)) == NULL) {
157 			syslog(LOG_ERR, gettext("cannot get transport info"));
158 			exit(1);
159 		}
160 
161 		if (strcmp(mname, "sockmod") == 0) {
162 			if (ioctl(0, I_POP, 0) || ioctl(0, I_PUSH, "timod")) {
163 				syslog(LOG_ERR,
164 				    gettext("could not get the "
165 				    "right module"));
166 				exit(1);
167 			}
168 		}
169 		if (!rpc_control(RPC_SVC_CONNMAXREC_SET, &maxrecsz)) {
170 			syslog(LOG_ERR,
171 			    gettext("unable to set RPC max record size"));
172 			exit(1);
173 		}
174 		/* XXX - is nconf even needed here? */
175 		if ((transp = svc_tli_create(0, nconf, NULL, 0, 0)) == NULL) {
176 			syslog(LOG_ERR, gettext("cannot create server handle"));
177 			exit(1);
178 		}
179 
180 		/*
181 		 * We use a NULL nconf because GSSPROG has already been
182 		 * registered with rpcbind.
183 		 */
184 		if (!svc_reg(transp, GSSPROG, GSSVERS, gssprog_1, NULL)) {
185 			syslog(LOG_ERR,
186 			    gettext("unable to register "
187 			    "(GSSPROG, GSSVERS)"));
188 			exit(1);
189 		}
190 
191 		if (nconf)
192 			freenetconfigent(nconf);
193 	} else {
194 		if (!gssd_debug)
195 			daemonize_start();
196 
197 		openlog("gssd", LOG_PID, LOG_DAEMON);
198 
199 		if (svc_create_local_service(gssprog_1, GSSPROG, GSSVERS,
200 		    "netpath", "gssd") == 0) {
201 			syslog(LOG_ERR, gettext("unable to create service"));
202 			exit(1);
203 		}
204 
205 		/* service created, now the daemon parent can exit */
206 		daemonize_ready(0);
207 	}
208 
209 
210 	if (gssd_debug) {
211 		fprintf(stderr,
212 		    gettext("gssd start: \n"));
213 	}
214 	svc_run();
215 	abort();
216 	/*NOTREACHED*/
217 #ifdef	lint
218 	return (1);
219 #endif
220 }
221 
222 static void
usage(void)223 usage(void)
224 {
225 	(void) fprintf(stderr, gettext("usage: gssd [-dg]\n"));
226 	exit(1);
227 }
228 
229 
230 /*
231  * Fork, detach from tty, etc...
232  */
233 static int write_pipe_fd = -1;
234 static
235 void
daemonize_start()236 daemonize_start()
237 {
238 	int pipe_fds[2];
239 	unsigned char status = 1;
240 
241 	closefrom(0);
242 
243 	/* Open stdin/out/err, chdir, get a pipe */
244 	if (open("/dev/null", O_RDONLY) < 0 ||
245 	    open("/dev/null", O_WRONLY) < 0 || dup(1) < 0 ||
246 	    chdir("/") < 0 || pipe(pipe_fds) < 0)
247 		exit(1);
248 
249 	/* For daemonize_ready() */
250 	write_pipe_fd = pipe_fds[1];
251 
252 	switch (fork()) {
253 	case -1:
254 		exit(1);
255 		/* NOTREACHED */
256 	case 0:
257 		break;
258 	default:
259 		/* Wait for child to be ready befor exiting */
260 		(void) close(pipe_fds[1]);
261 		(void) signal(SIGPIPE, SIG_DFL);
262 		(void) read(pipe_fds[0], &status, sizeof (status));
263 		exit(status);
264 	}
265 
266 	(void) close(pipe_fds[0]);
267 	(void) setsid();
268 }
269 
270 static
271 void
daemonize_ready(unsigned char status)272 daemonize_ready(unsigned char status)
273 {
274 	if (write_pipe_fd == -1)
275 		return;
276 
277 	(void) write(write_pipe_fd, &status, sizeof (status));
278 	(void) close(write_pipe_fd);
279 	write_pipe_fd = -1;
280 }
281 
282 /*ARGSUSED*/
283 int
gssprog_1_freeresult(SVCXPRT * transport,xdrproc_t xdr_res,caddr_t res)284 gssprog_1_freeresult(SVCXPRT *transport, xdrproc_t xdr_res, caddr_t res)
285 {
286 	xdr_free(xdr_res, res);
287 	return (1);
288 }
289