1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 2009, Sun Microsystems, Inc.
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 are met:
9 * - Redistributions of source code must retain the above copyright notice,
10 *   this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright notice,
12 *   this list of conditions and the following disclaimer in the documentation
13 *   and/or other materials provided with the distribution.
14 * - Neither the name of Sun Microsystems, Inc. nor the names of its
15 *   contributors may be used to endorse or promote products derived
16 *   from this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
19 * AND 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 COPYRIGHT HOLDER OR CONTRIBUTORS BE
22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28 * POSSIBILITY OF SUCH DAMAGE.
29 */
30/*
31 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
32 */
33
34#ident	"@(#)key_call.c	1.25	94/04/24 SMI"
35#include <sys/cdefs.h>
36__FBSDID("$FreeBSD$");
37
38/*
39 * key_call.c, Interface to keyserver
40 *
41 * setsecretkey(key) - set your secret key
42 * encryptsessionkey(agent, deskey) - encrypt a session key to talk to agent
43 * decryptsessionkey(agent, deskey) - decrypt ditto
44 * gendeskey(deskey) - generate a secure des key
45 */
46
47#include "namespace.h"
48#include "reentrant.h"
49#include <stdio.h>
50#include <stdlib.h>
51#include <unistd.h>
52#include <errno.h>
53#include <rpc/rpc.h>
54#include <rpc/auth.h>
55#include <rpc/auth_unix.h>
56#include <rpc/key_prot.h>
57#include <string.h>
58#include <netconfig.h>
59#include <sys/utsname.h>
60#include <stdlib.h>
61#include <signal.h>
62#include <sys/wait.h>
63#include <sys/fcntl.h>
64#include "un-namespace.h"
65#include "mt_misc.h"
66
67
68#define	KEY_TIMEOUT	5	/* per-try timeout in seconds */
69#define	KEY_NRETRY	12	/* number of retries */
70
71#ifdef DEBUG
72#define	debug(msg)	(void) fprintf(stderr, "%s\n", msg);
73#else
74#define	debug(msg)
75#endif /* DEBUG */
76
77/*
78 * Hack to allow the keyserver to use AUTH_DES (for authenticated
79 * NIS+ calls, for example).  The only functions that get called
80 * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
81 *
82 * The approach is to have the keyserver fill in pointers to local
83 * implementations of these functions, and to call those in key_call().
84 */
85
86cryptkeyres *(*__key_encryptsession_pk_LOCAL)(uid_t, void *arg) = 0;
87cryptkeyres *(*__key_decryptsession_pk_LOCAL)(uid_t, void *arg) = 0;
88des_block *(*__key_gendes_LOCAL)(uid_t, void *) = 0;
89
90static int key_call( u_long, xdrproc_t, void *, xdrproc_t, void *);
91
92int
93key_setsecret(const char *secretkey)
94{
95	keystatus status;
96
97	if (!key_call((u_long) KEY_SET, (xdrproc_t)xdr_keybuf,
98			(void *)secretkey,
99			(xdrproc_t)xdr_keystatus, &status)) {
100		return (-1);
101	}
102	if (status != KEY_SUCCESS) {
103		debug("set status is nonzero");
104		return (-1);
105	}
106	return (0);
107}
108
109
110/* key_secretkey_is_set() returns 1 if the keyserver has a secret key
111 * stored for the caller's effective uid; it returns 0 otherwise
112 *
113 * N.B.:  The KEY_NET_GET key call is undocumented.  Applications shouldn't
114 * be using it, because it allows them to get the user's secret key.
115 */
116
117int
118key_secretkey_is_set(void)
119{
120	struct key_netstres 	kres;
121
122	memset((void*)&kres, 0, sizeof (kres));
123	if (key_call((u_long) KEY_NET_GET, (xdrproc_t)xdr_void, NULL,
124			(xdrproc_t)xdr_key_netstres, &kres) &&
125	    (kres.status == KEY_SUCCESS) &&
126	    (kres.key_netstres_u.knet.st_priv_key[0] != 0)) {
127		/* avoid leaving secret key in memory */
128		memset(kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
129		return (1);
130	}
131	return (0);
132}
133
134int
135key_encryptsession_pk(char *remotename, netobj *remotekey, des_block *deskey)
136{
137	cryptkeyarg2 arg;
138	cryptkeyres res;
139
140	arg.remotename = remotename;
141	arg.remotekey = *remotekey;
142	arg.deskey = *deskey;
143	if (!key_call((u_long)KEY_ENCRYPT_PK, (xdrproc_t)xdr_cryptkeyarg2, &arg,
144			(xdrproc_t)xdr_cryptkeyres, &res)) {
145		return (-1);
146	}
147	if (res.status != KEY_SUCCESS) {
148		debug("encrypt status is nonzero");
149		return (-1);
150	}
151	*deskey = res.cryptkeyres_u.deskey;
152	return (0);
153}
154
155int
156key_decryptsession_pk(char *remotename, netobj *remotekey, des_block *deskey)
157{
158	cryptkeyarg2 arg;
159	cryptkeyres res;
160
161	arg.remotename = remotename;
162	arg.remotekey = *remotekey;
163	arg.deskey = *deskey;
164	if (!key_call((u_long)KEY_DECRYPT_PK, (xdrproc_t)xdr_cryptkeyarg2, &arg,
165			(xdrproc_t)xdr_cryptkeyres, &res)) {
166		return (-1);
167	}
168	if (res.status != KEY_SUCCESS) {
169		debug("decrypt status is nonzero");
170		return (-1);
171	}
172	*deskey = res.cryptkeyres_u.deskey;
173	return (0);
174}
175
176int
177key_encryptsession(const char *remotename, des_block *deskey)
178{
179	cryptkeyarg arg;
180	cryptkeyres res;
181
182	arg.remotename = (char *) remotename;
183	arg.deskey = *deskey;
184	if (!key_call((u_long)KEY_ENCRYPT, (xdrproc_t)xdr_cryptkeyarg, &arg,
185			(xdrproc_t)xdr_cryptkeyres, &res)) {
186		return (-1);
187	}
188	if (res.status != KEY_SUCCESS) {
189		debug("encrypt status is nonzero");
190		return (-1);
191	}
192	*deskey = res.cryptkeyres_u.deskey;
193	return (0);
194}
195
196int
197key_decryptsession(const char *remotename, des_block *deskey)
198{
199	cryptkeyarg arg;
200	cryptkeyres res;
201
202	arg.remotename = (char *) remotename;
203	arg.deskey = *deskey;
204	if (!key_call((u_long)KEY_DECRYPT, (xdrproc_t)xdr_cryptkeyarg, &arg,
205			(xdrproc_t)xdr_cryptkeyres, &res)) {
206		return (-1);
207	}
208	if (res.status != KEY_SUCCESS) {
209		debug("decrypt status is nonzero");
210		return (-1);
211	}
212	*deskey = res.cryptkeyres_u.deskey;
213	return (0);
214}
215
216int
217key_gendes(des_block *key)
218{
219	if (!key_call((u_long)KEY_GEN, (xdrproc_t)xdr_void, NULL,
220			(xdrproc_t)xdr_des_block, key)) {
221		return (-1);
222	}
223	return (0);
224}
225
226int
227key_setnet(struct key_netstarg *arg)
228{
229	keystatus status;
230
231
232	if (!key_call((u_long) KEY_NET_PUT, (xdrproc_t)xdr_key_netstarg, arg,
233			(xdrproc_t)xdr_keystatus, &status)){
234		return (-1);
235	}
236
237	if (status != KEY_SUCCESS) {
238		debug("key_setnet status is nonzero");
239		return (-1);
240	}
241	return (1);
242}
243
244
245int
246key_get_conv(char *pkey, des_block *deskey)
247{
248	cryptkeyres res;
249
250	if (!key_call((u_long) KEY_GET_CONV, (xdrproc_t)xdr_keybuf, pkey,
251			(xdrproc_t)xdr_cryptkeyres, &res)) {
252		return (-1);
253	}
254	if (res.status != KEY_SUCCESS) {
255		debug("get_conv status is nonzero");
256		return (-1);
257	}
258	*deskey = res.cryptkeyres_u.deskey;
259	return (0);
260}
261
262struct  key_call_private {
263	CLIENT	*client;	/* Client handle */
264	pid_t	pid;		/* process-id at moment of creation */
265	uid_t	uid;		/* user-id at last authorization */
266};
267static struct key_call_private *key_call_private_main = NULL;
268static thread_key_t key_call_key;
269static once_t key_call_once = ONCE_INITIALIZER;
270static int key_call_key_error;
271
272static void
273key_call_destroy(void *vp)
274{
275	struct key_call_private *kcp = (struct key_call_private *)vp;
276
277	if (kcp) {
278		if (kcp->client)
279			clnt_destroy(kcp->client);
280		free(kcp);
281	}
282}
283
284static void
285key_call_init(void)
286{
287
288	key_call_key_error = thr_keycreate(&key_call_key, key_call_destroy);
289}
290
291/*
292 * Keep the handle cached.  This call may be made quite often.
293 */
294static CLIENT *
295getkeyserv_handle(int vers)
296{
297	void *localhandle;
298	struct netconfig *nconf;
299	struct netconfig *tpconf;
300	struct key_call_private *kcp;
301	struct timeval wait_time;
302	struct utsname u;
303	int main_thread;
304	int fd;
305
306#define	TOTAL_TIMEOUT	30	/* total timeout talking to keyserver */
307#define	TOTAL_TRIES	5	/* Number of tries */
308
309	if ((main_thread = thr_main())) {
310		kcp = key_call_private_main;
311	} else {
312		if (thr_once(&key_call_once, key_call_init) != 0 ||
313		    key_call_key_error != 0)
314			return ((CLIENT *) NULL);
315		kcp = (struct key_call_private *)thr_getspecific(key_call_key);
316	}
317	if (kcp == (struct key_call_private *)NULL) {
318		kcp = (struct key_call_private *)malloc(sizeof (*kcp));
319		if (kcp == (struct key_call_private *)NULL) {
320			return ((CLIENT *) NULL);
321		}
322                if (main_thread)
323                        key_call_private_main = kcp;
324                else
325                        thr_setspecific(key_call_key, (void *) kcp);
326		kcp->client = NULL;
327	}
328
329	/* if pid has changed, destroy client and rebuild */
330	if (kcp->client != NULL && kcp->pid != getpid()) {
331		clnt_destroy(kcp->client);
332		kcp->client = NULL;
333	}
334
335	if (kcp->client != NULL) {
336		/* if uid has changed, build client handle again */
337		if (kcp->uid != geteuid()) {
338			kcp->uid = geteuid();
339			auth_destroy(kcp->client->cl_auth);
340			kcp->client->cl_auth =
341				authsys_create("", kcp->uid, 0, 0, NULL);
342			if (kcp->client->cl_auth == NULL) {
343				clnt_destroy(kcp->client);
344				kcp->client = NULL;
345				return ((CLIENT *) NULL);
346			}
347		}
348		/* Change the version number to the new one */
349		clnt_control(kcp->client, CLSET_VERS, (void *)&vers);
350		return (kcp->client);
351	}
352	if (!(localhandle = setnetconfig())) {
353		return ((CLIENT *) NULL);
354	}
355        tpconf = NULL;
356#if defined(__FreeBSD__)
357	if (uname(&u) == -1)
358#else
359#if defined(i386)
360	if (_nuname(&u) == -1)
361#elif defined(sparc)
362	if (_uname(&u) == -1)
363#else
364#error Unknown architecture!
365#endif
366#endif
367	{
368		endnetconfig(localhandle);
369		return ((CLIENT *) NULL);
370        }
371	while ((nconf = getnetconfig(localhandle)) != NULL) {
372		if (strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
373			/*
374			 * We use COTS_ORD here so that the caller can
375			 * find out immediately if the server is dead.
376			 */
377			if (nconf->nc_semantics == NC_TPI_COTS_ORD) {
378				kcp->client = clnt_tp_create(u.nodename,
379					KEY_PROG, vers, nconf);
380				if (kcp->client)
381					break;
382			} else {
383				tpconf = nconf;
384			}
385		}
386	}
387	if ((kcp->client == (CLIENT *) NULL) && (tpconf))
388		/* Now, try the CLTS or COTS loopback transport */
389		kcp->client = clnt_tp_create(u.nodename,
390			KEY_PROG, vers, tpconf);
391	endnetconfig(localhandle);
392
393	if (kcp->client == (CLIENT *) NULL) {
394		return ((CLIENT *) NULL);
395        }
396	kcp->uid = geteuid();
397	kcp->pid = getpid();
398	kcp->client->cl_auth = authsys_create("", kcp->uid, 0, 0, NULL);
399	if (kcp->client->cl_auth == NULL) {
400		clnt_destroy(kcp->client);
401		kcp->client = NULL;
402		return ((CLIENT *) NULL);
403	}
404
405	wait_time.tv_sec = TOTAL_TIMEOUT/TOTAL_TRIES;
406	wait_time.tv_usec = 0;
407	(void) clnt_control(kcp->client, CLSET_RETRY_TIMEOUT,
408		(char *)&wait_time);
409	if (clnt_control(kcp->client, CLGET_FD, (char *)&fd))
410		_fcntl(fd, F_SETFD, 1);	/* make it "close on exec" */
411
412	return (kcp->client);
413}
414
415/* returns  0 on failure, 1 on success */
416
417static int
418key_call(u_long proc, xdrproc_t xdr_arg, void *arg, xdrproc_t xdr_rslt,
419    void *rslt)
420{
421	CLIENT *clnt;
422	struct timeval wait_time;
423
424	if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL) {
425		cryptkeyres *res;
426		res = (*__key_encryptsession_pk_LOCAL)(geteuid(), arg);
427		*(cryptkeyres*)rslt = *res;
428		return (1);
429	} else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL) {
430		cryptkeyres *res;
431		res = (*__key_decryptsession_pk_LOCAL)(geteuid(), arg);
432		*(cryptkeyres*)rslt = *res;
433		return (1);
434	} else if (proc == KEY_GEN && __key_gendes_LOCAL) {
435		des_block *res;
436		res = (*__key_gendes_LOCAL)(geteuid(), 0);
437		*(des_block*)rslt = *res;
438		return (1);
439	}
440
441	if ((proc == KEY_ENCRYPT_PK) || (proc == KEY_DECRYPT_PK) ||
442	    (proc == KEY_NET_GET) || (proc == KEY_NET_PUT) ||
443	    (proc == KEY_GET_CONV))
444		clnt = getkeyserv_handle(2); /* talk to version 2 */
445	else
446		clnt = getkeyserv_handle(1); /* talk to version 1 */
447
448	if (clnt == NULL) {
449		return (0);
450	}
451
452	wait_time.tv_sec = TOTAL_TIMEOUT;
453	wait_time.tv_usec = 0;
454
455	if (clnt_call(clnt, proc, xdr_arg, arg, xdr_rslt, rslt,
456		wait_time) == RPC_SUCCESS) {
457		return (1);
458	} else {
459		return (0);
460	}
461}
462