1/*
2 * Copyright (c) 2010, Oracle America, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following
12 * disclaimer in the documentation and/or other materials
13 * provided with the distribution.
14 * * Neither the name of the "Oracle America, 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
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
22 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
23 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
25 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
27 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 */
31/*
32 * The original source is from the RPCSRC 4.0 package from Sun Microsystems.
33 * The Interface to keyserver protocoll 2, RPC over AF_UNIX and Linux/doors
34 * was added by Thorsten Kukuk <kukuk@suse.de>
35 * Since the Linux/doors project was stopped, I doubt that this code will
36 * ever be useful <kukuk@suse.de>.
37 */
38
39#include <stdio.h>
40#include <errno.h>
41#include <fcntl.h>
42#include <signal.h>
43#include <unistd.h>
44#include <string.h>
45#include <rpc/rpc.h>
46#include <rpc/auth.h>
47#include <sys/wait.h>
48#include <sys/param.h>
49#include <sys/socket.h>
50#include <rpc/key_prot.h>
51#include <libc-lock.h>
52
53#define KEY_TIMEOUT 5 /* per-try timeout in seconds */
54#define KEY_NRETRY 12 /* number of retries */
55
56#define debug(msg) /* turn off debugging */
57
58#ifndef SO_PASSCRED
59extern int _openchild (const char *command, FILE **fto, FILE **ffrom);
60#endif
61
62static int key_call (u_long, xdrproc_t xdr_arg, char *,
63 xdrproc_t xdr_rslt, char *) internal_function;
64
65static const struct timeval trytimeout = {KEY_TIMEOUT, 0};
66static const struct timeval tottimeout = {KEY_TIMEOUT *KEY_NRETRY, 0};
67
68int
69key_setsecret (char *secretkey)
70{
71 keystatus status;
72
73 if (!key_call ((u_long) KEY_SET, (xdrproc_t) xdr_keybuf, secretkey,
74 (xdrproc_t) xdr_keystatus, (char *) &status))
75 return -1;
76 if (status != KEY_SUCCESS)
77 {
78 debug ("set status is nonzero");
79 return -1;
80 }
81 return 0;
82}
83libc_hidden_nolink_sunrpc (key_setsecret, GLIBC_2_1)
84
85/* key_secretkey_is_set() returns 1 if the keyserver has a secret key
86 * stored for the caller's effective uid; it returns 0 otherwise
87 *
88 * N.B.: The KEY_NET_GET key call is undocumented. Applications shouldn't
89 * be using it, because it allows them to get the user's secret key.
90 */
91int
92key_secretkey_is_set (void)
93{
94 struct key_netstres kres;
95
96 memset (&kres, 0, sizeof (kres));
97 if (key_call ((u_long) KEY_NET_GET, (xdrproc_t) xdr_void,
98 (char *) NULL, (xdrproc_t) xdr_key_netstres,
99 (char *) &kres) &&
100 (kres.status == KEY_SUCCESS) &&
101 (kres.key_netstres_u.knet.st_priv_key[0] != 0))
102 {
103 /* avoid leaving secret key in memory */
104 memset (kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
105 return 1;
106 }
107 return 0;
108}
109#ifdef EXPORT_RPC_SYMBOLS
110libc_hidden_def (key_secretkey_is_set)
111#else
112libc_hidden_nolink_sunrpc (key_secretkey_is_set, GLIBC_2_1)
113#endif
114
115int
116key_encryptsession (char *remotename, des_block *deskey)
117{
118 cryptkeyarg arg;
119 cryptkeyres res;
120
121 arg.remotename = remotename;
122 arg.deskey = *deskey;
123 if (!key_call ((u_long) KEY_ENCRYPT, (xdrproc_t) xdr_cryptkeyarg,
124 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
125 (char *) &res))
126 return -1;
127
128 if (res.status != KEY_SUCCESS)
129 {
130 debug ("encrypt status is nonzero");
131 return -1;
132 }
133 *deskey = res.cryptkeyres_u.deskey;
134 return 0;
135}
136libc_hidden_nolink_sunrpc (key_encryptsession, GLIBC_2_1)
137
138int
139key_decryptsession (char *remotename, des_block *deskey)
140{
141 cryptkeyarg arg;
142 cryptkeyres res;
143
144 arg.remotename = remotename;
145 arg.deskey = *deskey;
146 if (!key_call ((u_long) KEY_DECRYPT, (xdrproc_t) xdr_cryptkeyarg,
147 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
148 (char *) &res))
149 return -1;
150 if (res.status != KEY_SUCCESS)
151 {
152 debug ("decrypt status is nonzero");
153 return -1;
154 }
155 *deskey = res.cryptkeyres_u.deskey;
156 return 0;
157}
158libc_hidden_nolink_sunrpc (key_decryptsession, GLIBC_2_1)
159
160int
161key_encryptsession_pk (char *remotename, netobj *remotekey,
162 des_block *deskey)
163{
164 cryptkeyarg2 arg;
165 cryptkeyres res;
166
167 arg.remotename = remotename;
168 arg.remotekey = *remotekey;
169 arg.deskey = *deskey;
170 if (!key_call ((u_long) KEY_ENCRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
171 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
172 (char *) &res))
173 return -1;
174
175 if (res.status != KEY_SUCCESS)
176 {
177 debug ("encrypt status is nonzero");
178 return -1;
179 }
180 *deskey = res.cryptkeyres_u.deskey;
181 return 0;
182}
183libc_hidden_nolink_sunrpc (key_encryptsession_pk, GLIBC_2_1)
184
185int
186key_decryptsession_pk (char *remotename, netobj *remotekey,
187 des_block *deskey)
188{
189 cryptkeyarg2 arg;
190 cryptkeyres res;
191
192 arg.remotename = remotename;
193 arg.remotekey = *remotekey;
194 arg.deskey = *deskey;
195 if (!key_call ((u_long) KEY_DECRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
196 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
197 (char *) &res))
198 return -1;
199
200 if (res.status != KEY_SUCCESS)
201 {
202 debug ("decrypt status is nonzero");
203 return -1;
204 }
205 *deskey = res.cryptkeyres_u.deskey;
206 return 0;
207}
208libc_hidden_nolink_sunrpc (key_decryptsession_pk, GLIBC_2_1)
209
210int
211key_gendes (des_block *key)
212{
213 struct sockaddr_in sin;
214 CLIENT *client;
215 int socket;
216 enum clnt_stat stat;
217
218 sin.sin_family = AF_INET;
219 sin.sin_port = 0;
220 sin.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
221 __bzero (sin.sin_zero, sizeof (sin.sin_zero));
222 socket = RPC_ANYSOCK;
223 client = clntudp_bufcreate (&sin, (u_long) KEY_PROG, (u_long) KEY_VERS,
224 trytimeout, &socket, RPCSMALLMSGSIZE,
225 RPCSMALLMSGSIZE);
226 if (client == NULL)
227 return -1;
228
229 stat = clnt_call (client, KEY_GEN, (xdrproc_t) xdr_void, NULL,
230 (xdrproc_t) xdr_des_block, (caddr_t) key,
231 tottimeout);
232 clnt_destroy (client);
233 __close (socket);
234 if (stat != RPC_SUCCESS)
235 return -1;
236
237 return 0;
238}
239#ifdef EXPORT_RPC_SYMBOLS
240libc_hidden_def (key_gendes)
241#else
242libc_hidden_nolink_sunrpc (key_gendes, GLIBC_2_1)
243#endif
244
245int
246key_setnet (struct key_netstarg *arg)
247{
248 keystatus status;
249
250 if (!key_call ((u_long) KEY_NET_PUT, (xdrproc_t) xdr_key_netstarg,
251 (char *) arg,(xdrproc_t) xdr_keystatus,
252 (char *) &status))
253 return -1;
254
255 if (status != KEY_SUCCESS)
256 {
257 debug ("key_setnet status is nonzero");
258 return -1;
259 }
260 return 1;
261}
262libc_hidden_nolink_sunrpc (key_setnet, GLIBC_2_1)
263
264int
265key_get_conv (char *pkey, des_block *deskey)
266{
267 cryptkeyres res;
268
269 if (!key_call ((u_long) KEY_GET_CONV, (xdrproc_t) xdr_keybuf, pkey,
270 (xdrproc_t) xdr_cryptkeyres, (char *) &res))
271 return -1;
272
273 if (res.status != KEY_SUCCESS)
274 {
275 debug ("get_conv status is nonzero");
276 return -1;
277 }
278 *deskey = res.cryptkeyres_u.deskey;
279 return 0;
280}
281libc_hidden_nolink_sunrpc (key_get_conv, GLIBC_2_1)
282
283/*
284 * Hack to allow the keyserver to use AUTH_DES (for authenticated
285 * NIS+ calls, for example). The only functions that get called
286 * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
287 *
288 * The approach is to have the keyserver fill in pointers to local
289 * implementations of these functions, and to call those in key_call().
290 */
291
292cryptkeyres *(*__key_encryptsession_pk_LOCAL) (uid_t, char *);
293cryptkeyres *(*__key_decryptsession_pk_LOCAL) (uid_t, char *);
294des_block *(*__key_gendes_LOCAL) (uid_t, char *);
295
296#ifndef SO_PASSCRED
297static int
298internal_function
299key_call_keyenvoy (u_long proc, xdrproc_t xdr_arg, char *arg,
300 xdrproc_t xdr_rslt, char *rslt)
301{
302 XDR xdrargs;
303 XDR xdrrslt;
304 FILE *fargs;
305 FILE *frslt;
306 sigset_t oldmask, mask;
307 int status;
308 int pid;
309 int success;
310 uid_t ruid;
311 uid_t euid;
312 static const char MESSENGER[] = "/usr/etc/keyenvoy";
313
314 success = 1;
315 sigemptyset (&mask);
316 sigaddset (&mask, SIGCHLD);
317 __sigprocmask (SIG_BLOCK, &mask, &oldmask);
318
319 /*
320 * We are going to exec a set-uid program which makes our effective uid
321 * zero, and authenticates us with our real uid. We need to make the
322 * effective uid be the real uid for the setuid program, and
323 * the real uid be the effective uid so that we can change things back.
324 */
325 euid = __geteuid ();
326 ruid = __getuid ();
327 __setreuid (euid, ruid);
328 pid = _openchild (MESSENGER, &fargs, &frslt);
329 __setreuid (ruid, euid);
330 if (pid < 0)
331 {
332 debug ("open_streams");
333 __sigprocmask (SIG_SETMASK, &oldmask, NULL);
334 return (0);
335 }
336 xdrstdio_create (&xdrargs, fargs, XDR_ENCODE);
337 xdrstdio_create (&xdrrslt, frslt, XDR_DECODE);
338
339 if (!xdr_u_long (&xdrargs, &proc) || !(*xdr_arg) (&xdrargs, arg))
340 {
341 debug ("xdr args");
342 success = 0;
343 }
344 fclose (fargs);
345
346 if (success && !(*xdr_rslt) (&xdrrslt, rslt))
347 {
348 debug ("xdr rslt");
349 success = 0;
350 }
351 fclose(frslt);
352
353 wait_again:
354 if (__wait4 (pid, &status, 0, NULL) < 0)
355 {
356 if (errno == EINTR)
357 goto wait_again;
358 debug ("wait4");
359 if (errno == ECHILD || errno == ESRCH)
360 perror ("wait");
361 else
362 success = 0;
363 }
364 else
365 if (status != 0)
366 {
367 debug ("wait4 1");
368 success = 0;
369 }
370 __sigprocmask (SIG_SETMASK, &oldmask, NULL);
371
372 return success;
373}
374#endif
375
376struct key_call_private {
377 CLIENT *client; /* Client handle */
378 pid_t pid; /* process-id at moment of creation */
379 uid_t uid; /* user-id at last authorization */
380};
381#ifdef _RPC_THREAD_SAFE_
382#define key_call_private_main RPC_THREAD_VARIABLE(key_call_private_s)
383#else
384static struct key_call_private *key_call_private_main;
385#endif
386__libc_lock_define_initialized (static, keycall_lock)
387
388/*
389 * Keep the handle cached. This call may be made quite often.
390 */
391static CLIENT *
392getkeyserv_handle (int vers)
393{
394 struct key_call_private *kcp = key_call_private_main;
395 struct timeval wait_time;
396 int fd;
397 struct sockaddr_un name;
398 socklen_t namelen = sizeof(struct sockaddr_un);
399
400#define TOTAL_TIMEOUT 30 /* total timeout talking to keyserver */
401#define TOTAL_TRIES 5 /* Number of tries */
402
403 if (kcp == (struct key_call_private *)NULL)
404 {
405 kcp = (struct key_call_private *)malloc (sizeof (*kcp));
406 if (kcp == (struct key_call_private *)NULL)
407 return (CLIENT *) NULL;
408
409 key_call_private_main = kcp;
410 kcp->client = NULL;
411 }
412
413 /* if pid has changed, destroy client and rebuild */
414 if (kcp->client != NULL && kcp->pid != __getpid ())
415 {
416 auth_destroy (kcp->client->cl_auth);
417 clnt_destroy (kcp->client);
418 kcp->client = NULL;
419 }
420
421 if (kcp->client != NULL)
422 {
423 /* if other side closed socket, build handle again */
424 clnt_control (kcp->client, CLGET_FD, (char *)&fd);
425 if (__getpeername (fd,(struct sockaddr *)&name,&namelen) == -1)
426 {
427 auth_destroy (kcp->client->cl_auth);
428 clnt_destroy (kcp->client);
429 kcp->client = NULL;
430 }
431 }
432
433 if (kcp->client != NULL)
434 {
435 /* if uid has changed, build client handle again */
436 if (kcp->uid != __geteuid ())
437 {
438 kcp->uid = __geteuid ();
439 auth_destroy (kcp->client->cl_auth);
440 kcp->client->cl_auth =
441 authunix_create ((char *)"", kcp->uid, 0, 0, NULL);
442 if (kcp->client->cl_auth == NULL)
443 {
444 clnt_destroy (kcp->client);
445 kcp->client = NULL;
446 return ((CLIENT *) NULL);
447 }
448 }
449 /* Change the version number to the new one */
450 clnt_control (kcp->client, CLSET_VERS, (void *)&vers);
451 return kcp->client;
452 }
453
454 if ((kcp->client == (CLIENT *) NULL))
455 /* Use the AF_UNIX transport */
456 kcp->client = clnt_create ("/var/run/keyservsock", KEY_PROG, vers, "unix");
457
458 if (kcp->client == (CLIENT *) NULL)
459 return (CLIENT *) NULL;
460
461 kcp->uid = __geteuid ();
462 kcp->pid = __getpid ();
463 kcp->client->cl_auth = authunix_create ((char *)"", kcp->uid, 0, 0, NULL);
464 if (kcp->client->cl_auth == NULL)
465 {
466 clnt_destroy (kcp->client);
467 kcp->client = NULL;
468 return (CLIENT *) NULL;
469 }
470
471 wait_time.tv_sec = TOTAL_TIMEOUT/TOTAL_TRIES;
472 wait_time.tv_usec = 0;
473 clnt_control (kcp->client, CLSET_RETRY_TIMEOUT,
474 (char *)&wait_time);
475 if (clnt_control (kcp->client, CLGET_FD, (char *)&fd))
476 __fcntl (fd, F_SETFD, FD_CLOEXEC); /* make it "close on exec" */
477
478 return kcp->client;
479}
480
481/* returns 0 on failure, 1 on success */
482static int
483internal_function
484key_call_socket (u_long proc, xdrproc_t xdr_arg, char *arg,
485 xdrproc_t xdr_rslt, char *rslt)
486{
487 CLIENT *clnt;
488 struct timeval wait_time;
489 int result = 0;
490
491 __libc_lock_lock (keycall_lock);
492 if ((proc == KEY_ENCRYPT_PK) || (proc == KEY_DECRYPT_PK) ||
493 (proc == KEY_NET_GET) || (proc == KEY_NET_PUT) ||
494 (proc == KEY_GET_CONV))
495 clnt = getkeyserv_handle(2); /* talk to version 2 */
496 else
497 clnt = getkeyserv_handle(1); /* talk to version 1 */
498
499 if (clnt != NULL)
500 {
501 wait_time.tv_sec = TOTAL_TIMEOUT;
502 wait_time.tv_usec = 0;
503
504 if (clnt_call (clnt, proc, xdr_arg, arg, xdr_rslt, rslt,
505 wait_time) == RPC_SUCCESS)
506 result = 1;
507 }
508
509 __libc_lock_unlock (keycall_lock);
510
511 return result;
512}
513
514
515/* returns 0 on failure, 1 on success */
516static int
517internal_function
518key_call (u_long proc, xdrproc_t xdr_arg, char *arg,
519 xdrproc_t xdr_rslt, char *rslt)
520{
521#ifndef SO_PASSCRED
522 static int use_keyenvoy;
523#endif
524
525 if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL)
526 {
527 cryptkeyres *res;
528 res = (*__key_encryptsession_pk_LOCAL) (__geteuid (), arg);
529 *(cryptkeyres *) rslt = *res;
530 return 1;
531 }
532 else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL)
533 {
534 cryptkeyres *res;
535 res = (*__key_decryptsession_pk_LOCAL) (__geteuid (), arg);
536 *(cryptkeyres *) rslt = *res;
537 return 1;
538 }
539 else if (proc == KEY_GEN && __key_gendes_LOCAL)
540 {
541 des_block *res;
542 res = (*__key_gendes_LOCAL) (__geteuid (), 0);
543 *(des_block *) rslt = *res;
544 return 1;
545 }
546
547#ifdef SO_PASSCRED
548 return key_call_socket (proc, xdr_arg, arg, xdr_rslt, rslt);
549#else
550 if (!use_keyenvoy)
551 {
552 if (key_call_socket (proc, xdr_arg, arg, xdr_rslt, rslt))
553 return 1;
554 use_keyenvoy = 1;
555 }
556 return key_call_keyenvoy (proc, xdr_arg, arg, xdr_rslt, rslt);
557#endif
558}
559
560#ifdef _RPC_THREAD_SAFE_
561void
562__rpc_thread_key_cleanup (void)
563{
564 struct key_call_private *kcp = RPC_THREAD_VARIABLE(key_call_private_s);
565
566 if (kcp) {
567 if (kcp->client) {
568 if (kcp->client->cl_auth)
569 auth_destroy (kcp->client->cl_auth);
570 clnt_destroy(kcp->client);
571 }
572 free (kcp);
573 }
574}
575#endif /* _RPC_THREAD_SAFE_ */
576