xref: /dragonfly/lib/libc/rpc/key_call.c (revision 19b217af)
1 /*
2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3  * unrestricted use provided that this legend is included on all tape
4  * media and as a part of the software program in whole or part.  Users
5  * may copy or modify Sun RPC without charge, but are not authorized
6  * to license or distribute it to anyone else except as part of a product or
7  * program developed by the user.
8  *
9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12  *
13  * Sun RPC is provided with no support and without any obligation on the
14  * part of Sun Microsystems, Inc. to assist in its use, correction,
15  * modification or enhancement.
16  *
17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19  * OR ANY PART THEREOF.
20  *
21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22  * or profits or other special, indirect and consequential damages, even if
23  * Sun has been advised of the possibility of such damages.
24  *
25  * Sun Microsystems, Inc.
26  * 2550 Garcia Avenue
27  * Mountain View, California  94043
28  */
29 /*
30  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
31  *
32  * @(#)key_call.c	1.25	94/04/24 SMI
33  * $FreeBSD: src/lib/libc/rpc/key_call.c,v 1.16 2006/02/27 22:10:59 deischen Exp $
34  */
35 
36 /*
37  * key_call.c, Interface to keyserver
38  *
39  * setsecretkey(key) - set your secret key
40  * encryptsessionkey(agent, deskey) - encrypt a session key to talk to agent
41  * decryptsessionkey(agent, deskey) - decrypt ditto
42  * gendeskey(deskey) - generate a secure des key
43  */
44 
45 #include "namespace.h"
46 #include "reentrant.h"
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <unistd.h>
50 #include <errno.h>
51 #include <rpc/rpc.h>
52 #include <rpc/auth.h>
53 #include <rpc/auth_unix.h>
54 #include <rpc/key_prot.h>
55 #include <string.h>
56 #include <netconfig.h>
57 #include <sys/utsname.h>
58 #include <signal.h>
59 #include <sys/wait.h>
60 #include <sys/fcntl.h>
61 #include "un-namespace.h"
62 #include "mt_misc.h"
63 
64 
65 #define	KEY_TIMEOUT	5	/* per-try timeout in seconds */
66 #define	KEY_NRETRY	12	/* number of retries */
67 
68 #ifdef DEBUG
69 #define	debug(msg)	fprintf(stderr, "%s\n", msg);
70 #else
71 #define	debug(msg)
72 #endif /* DEBUG */
73 
74 /*
75  * Hack to allow the keyserver to use AUTH_DES (for authenticated
76  * NIS+ calls, for example).  The only functions that get called
77  * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
78  *
79  * The approach is to have the keyserver fill in pointers to local
80  * implementations of these functions, and to call those in key_call().
81  */
82 
83 cryptkeyres *(*__key_encryptsession_pk_LOCAL)() = NULL;
84 cryptkeyres *(*__key_decryptsession_pk_LOCAL)() = NULL;
85 des_block *(*__key_gendes_LOCAL)() = NULL;
86 
87 static int key_call( u_long, xdrproc_t, void *, xdrproc_t, void *);
88 
89 int
90 key_setsecret(const char *secretkey)
91 {
92 	keystatus status;
93 
94 	if (!key_call((u_long) KEY_SET, (xdrproc_t)xdr_keybuf,
95 			(void *)secretkey,
96 			(xdrproc_t)xdr_keystatus, &status)) {
97 		return (-1);
98 	}
99 	if (status != KEY_SUCCESS) {
100 		debug("set status is nonzero");
101 		return (-1);
102 	}
103 	return (0);
104 }
105 
106 
107 /* key_secretkey_is_set() returns 1 if the keyserver has a secret key
108  * stored for the caller's effective uid; it returns 0 otherwise
109  *
110  * N.B.:  The KEY_NET_GET key call is undocumented.  Applications shouldn't
111  * be using it, because it allows them to get the user's secret key.
112  */
113 
114 int
115 key_secretkey_is_set(void)
116 {
117 	struct key_netstres 	kres;
118 
119 	memset((void*)&kres, 0, sizeof (kres));
120 	if (key_call((u_long) KEY_NET_GET, (xdrproc_t)xdr_void, NULL,
121 			(xdrproc_t)xdr_key_netstres, &kres) &&
122 	    (kres.status == KEY_SUCCESS) &&
123 	    (kres.key_netstres_u.knet.st_priv_key[0] != 0)) {
124 		/* avoid leaving secret key in memory */
125 		memset(kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
126 		return (1);
127 	}
128 	return (0);
129 }
130 
131 int
132 key_encryptsession_pk(char *remotename, netobj *remotekey, des_block *deskey)
133 {
134 	cryptkeyarg2 arg;
135 	cryptkeyres res;
136 
137 	arg.remotename = remotename;
138 	arg.remotekey = *remotekey;
139 	arg.deskey = *deskey;
140 	if (!key_call((u_long)KEY_ENCRYPT_PK, (xdrproc_t)xdr_cryptkeyarg2, &arg,
141 			(xdrproc_t)xdr_cryptkeyres, &res)) {
142 		return (-1);
143 	}
144 	if (res.status != KEY_SUCCESS) {
145 		debug("encrypt status is nonzero");
146 		return (-1);
147 	}
148 	*deskey = res.cryptkeyres_u.deskey;
149 	return (0);
150 }
151 
152 int
153 key_decryptsession_pk(char *remotename, netobj *remotekey, des_block *deskey)
154 {
155 	cryptkeyarg2 arg;
156 	cryptkeyres res;
157 
158 	arg.remotename = remotename;
159 	arg.remotekey = *remotekey;
160 	arg.deskey = *deskey;
161 	if (!key_call((u_long)KEY_DECRYPT_PK, (xdrproc_t)xdr_cryptkeyarg2, &arg,
162 			(xdrproc_t)xdr_cryptkeyres, &res)) {
163 		return (-1);
164 	}
165 	if (res.status != KEY_SUCCESS) {
166 		debug("decrypt status is nonzero");
167 		return (-1);
168 	}
169 	*deskey = res.cryptkeyres_u.deskey;
170 	return (0);
171 }
172 
173 int
174 key_encryptsession(const char *remotename, des_block *deskey)
175 {
176 	cryptkeyarg arg;
177 	cryptkeyres res;
178 
179 	arg.remotename = (char *) remotename;
180 	arg.deskey = *deskey;
181 	if (!key_call((u_long)KEY_ENCRYPT, (xdrproc_t)xdr_cryptkeyarg, &arg,
182 			(xdrproc_t)xdr_cryptkeyres, &res)) {
183 		return (-1);
184 	}
185 	if (res.status != KEY_SUCCESS) {
186 		debug("encrypt status is nonzero");
187 		return (-1);
188 	}
189 	*deskey = res.cryptkeyres_u.deskey;
190 	return (0);
191 }
192 
193 int
194 key_decryptsession(const char *remotename, des_block *deskey)
195 {
196 	cryptkeyarg arg;
197 	cryptkeyres res;
198 
199 	arg.remotename = (char *) remotename;
200 	arg.deskey = *deskey;
201 	if (!key_call((u_long)KEY_DECRYPT, (xdrproc_t)xdr_cryptkeyarg, &arg,
202 			(xdrproc_t)xdr_cryptkeyres, &res)) {
203 		return (-1);
204 	}
205 	if (res.status != KEY_SUCCESS) {
206 		debug("decrypt status is nonzero");
207 		return (-1);
208 	}
209 	*deskey = res.cryptkeyres_u.deskey;
210 	return (0);
211 }
212 
213 int
214 key_gendes(des_block *key)
215 {
216 	if (!key_call((u_long)KEY_GEN, (xdrproc_t)xdr_void, NULL,
217 			(xdrproc_t)xdr_des_block, key)) {
218 		return (-1);
219 	}
220 	return (0);
221 }
222 
223 int
224 key_setnet(struct key_netstarg *arg)
225 {
226 	keystatus status;
227 
228 
229 	if (!key_call((u_long) KEY_NET_PUT, (xdrproc_t)xdr_key_netstarg, arg,
230 			(xdrproc_t)xdr_keystatus, &status)){
231 		return (-1);
232 	}
233 
234 	if (status != KEY_SUCCESS) {
235 		debug("key_setnet status is nonzero");
236 		return (-1);
237 	}
238 	return (1);
239 }
240 
241 
242 int
243 key_get_conv(char *pkey, des_block *deskey)
244 {
245 	cryptkeyres res;
246 
247 	if (!key_call((u_long) KEY_GET_CONV, (xdrproc_t)xdr_keybuf, pkey,
248 			(xdrproc_t)xdr_cryptkeyres, &res)) {
249 		return (-1);
250 	}
251 	if (res.status != KEY_SUCCESS) {
252 		debug("get_conv status is nonzero");
253 		return (-1);
254 	}
255 	*deskey = res.cryptkeyres_u.deskey;
256 	return (0);
257 }
258 
259 struct  key_call_private {
260 	CLIENT	*client;	/* Client handle */
261 	pid_t	pid;		/* process-id at moment of creation */
262 	uid_t	uid;		/* user-id at last authorization */
263 };
264 static struct key_call_private *key_call_private_main = NULL;
265 
266 static void
267 key_call_destroy(void *vp)
268 {
269 	struct key_call_private *kcp = (struct key_call_private *)vp;
270 
271 	if (kcp) {
272 		if (kcp->client)
273 			clnt_destroy(kcp->client);
274 		free(kcp);
275 	}
276 }
277 
278 /*
279  * Keep the handle cached.  This call may be made quite often.
280  */
281 static CLIENT *
282 getkeyserv_handle(int vers)
283 {
284 	void *localhandle;
285 	struct netconfig *nconf;
286 	struct netconfig *tpconf;
287 	struct key_call_private *kcp = key_call_private_main;
288 	struct timeval wait_time;
289 	struct utsname u;
290 	int main_thread;
291 	int fd;
292 	static thread_key_t key_call_key;
293 
294 #define	TOTAL_TIMEOUT	30	/* total timeout talking to keyserver */
295 #define	TOTAL_TRIES	5	/* Number of tries */
296 
297 	if ((main_thread = thr_main())) {
298 		kcp = key_call_private_main;
299 	} else {
300 		if (key_call_key == 0) {
301 			mutex_lock(&tsd_lock);
302 			if (key_call_key == 0)
303 				thr_keycreate(&key_call_key, key_call_destroy);
304 			mutex_unlock(&tsd_lock);
305 		}
306 		kcp = (struct key_call_private *)thr_getspecific(key_call_key);
307 	}
308 	if (kcp == NULL) {
309 		kcp = (struct key_call_private *)malloc(sizeof (*kcp));
310 		if (kcp == NULL) {
311 			return (NULL);
312 		}
313 		if (main_thread)
314 			key_call_private_main = kcp;
315 		else
316 			thr_setspecific(key_call_key, (void *) kcp);
317 		kcp->client = NULL;
318 	}
319 
320 	/* if pid has changed, destroy client and rebuild */
321 	if (kcp->client != NULL && kcp->pid != getpid()) {
322 		clnt_destroy(kcp->client);
323 		kcp->client = NULL;
324 	}
325 
326 	if (kcp->client != NULL) {
327 		/* if uid has changed, build client handle again */
328 		if (kcp->uid != geteuid()) {
329 			kcp->uid = geteuid();
330 			auth_destroy(kcp->client->cl_auth);
331 			kcp->client->cl_auth =
332 				authsys_create("", kcp->uid, 0, 0, NULL);
333 			if (kcp->client->cl_auth == NULL) {
334 				clnt_destroy(kcp->client);
335 				kcp->client = NULL;
336 				return (NULL);
337 			}
338 		}
339 		/* Change the version number to the new one */
340 		clnt_control(kcp->client, CLSET_VERS, (void *)&vers);
341 		return (kcp->client);
342 	}
343 	if (!(localhandle = setnetconfig())) {
344 		return (NULL);
345 	}
346 	tpconf = NULL;
347 	if (uname(&u) == -1)
348 	{
349 		endnetconfig(localhandle);
350 		return (NULL);
351 	}
352 	while ((nconf = getnetconfig(localhandle)) != NULL) {
353 		if (strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
354 			/*
355 			 * We use COTS_ORD here so that the caller can
356 			 * find out immediately if the server is dead.
357 			 */
358 			if (nconf->nc_semantics == NC_TPI_COTS_ORD) {
359 				kcp->client = clnt_tp_create(u.nodename,
360 					KEY_PROG, vers, nconf);
361 				if (kcp->client)
362 					break;
363 			} else {
364 				tpconf = nconf;
365 			}
366 		}
367 	}
368 	if ((kcp->client == NULL) && (tpconf))
369 		/* Now, try the CLTS or COTS loopback transport */
370 		kcp->client = clnt_tp_create(u.nodename,
371 			KEY_PROG, vers, tpconf);
372 	endnetconfig(localhandle);
373 
374 	if (kcp->client == NULL) {
375 		return (NULL);
376 	}
377 	kcp->uid = geteuid();
378 	kcp->pid = getpid();
379 	kcp->client->cl_auth = authsys_create("", kcp->uid, 0, 0, NULL);
380 	if (kcp->client->cl_auth == NULL) {
381 		clnt_destroy(kcp->client);
382 		kcp->client = NULL;
383 		return (NULL);
384 	}
385 
386 	wait_time.tv_sec = TOTAL_TIMEOUT/TOTAL_TRIES;
387 	wait_time.tv_usec = 0;
388 	clnt_control(kcp->client, CLSET_RETRY_TIMEOUT,
389 		(char *)&wait_time);
390 	if (clnt_control(kcp->client, CLGET_FD, (char *)&fd))
391 		_fcntl(fd, F_SETFD, 1);	/* make it "close on exec" */
392 
393 	return (kcp->client);
394 }
395 
396 /* returns  0 on failure, 1 on success */
397 
398 static int
399 key_call(u_long proc, xdrproc_t xdr_arg, void *arg, xdrproc_t xdr_rslt,
400 	 void *rslt)
401 {
402 	CLIENT *clnt;
403 	struct timeval wait_time;
404 
405 	if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL) {
406 		cryptkeyres *res;
407 		res = (*__key_encryptsession_pk_LOCAL)(geteuid(), arg);
408 		*(cryptkeyres*)rslt = *res;
409 		return (1);
410 	} else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL) {
411 		cryptkeyres *res;
412 		res = (*__key_decryptsession_pk_LOCAL)(geteuid(), arg);
413 		*(cryptkeyres*)rslt = *res;
414 		return (1);
415 	} else if (proc == KEY_GEN && __key_gendes_LOCAL) {
416 		des_block *res;
417 		res = (*__key_gendes_LOCAL)(geteuid(), 0);
418 		*(des_block*)rslt = *res;
419 		return (1);
420 	}
421 
422 	if ((proc == KEY_ENCRYPT_PK) || (proc == KEY_DECRYPT_PK) ||
423 	    (proc == KEY_NET_GET) || (proc == KEY_NET_PUT) ||
424 	    (proc == KEY_GET_CONV))
425 		clnt = getkeyserv_handle(2); /* talk to version 2 */
426 	else
427 		clnt = getkeyserv_handle(1); /* talk to version 1 */
428 
429 	if (clnt == NULL) {
430 		return (0);
431 	}
432 
433 	wait_time.tv_sec = TOTAL_TIMEOUT;
434 	wait_time.tv_usec = 0;
435 
436 	if (clnt_call(clnt, proc, xdr_arg, arg, xdr_rslt, rslt,
437 		wait_time) == RPC_SUCCESS) {
438 		return (1);
439 	} else {
440 		return (0);
441 	}
442 }
443