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 protocol 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#include <shlib-compat.h>
53
54#define KEY_TIMEOUT 5 /* per-try timeout in seconds */
55#define KEY_NRETRY 12 /* number of retries */
56
57#define debug(msg) /* turn off debugging */
58
59#ifndef SO_PASSCRED
60extern int _openchild (const char *command, FILE **fto, FILE **ffrom);
61#endif
62
63static int key_call (u_long, xdrproc_t xdr_arg, char *,
64 xdrproc_t xdr_rslt, char *);
65
66static const struct timeval trytimeout = {KEY_TIMEOUT, 0};
67static const struct timeval tottimeout = {KEY_TIMEOUT *KEY_NRETRY, 0};
68
69int
70key_setsecret (char *secretkey)
71{
72 keystatus status;
73
74 if (!key_call ((u_long) KEY_SET, (xdrproc_t) xdr_keybuf, secretkey,
75 (xdrproc_t) xdr_keystatus, (char *) &status))
76 return -1;
77 if (status != KEY_SUCCESS)
78 {
79 debug ("set status is nonzero");
80 return -1;
81 }
82 return 0;
83}
84libc_hidden_nolink_sunrpc (key_setsecret, GLIBC_2_1)
85
86/* key_secretkey_is_set() returns 1 if the keyserver has a secret key
87 * stored for the caller's effective uid; it returns 0 otherwise
88 *
89 * N.B.: The KEY_NET_GET key call is undocumented. Applications shouldn't
90 * be using it, because it allows them to get the user's secret key.
91 */
92int
93key_secretkey_is_set (void)
94{
95 struct key_netstres kres;
96
97 memset (&kres, 0, sizeof (kres));
98 if (key_call ((u_long) KEY_NET_GET, (xdrproc_t) xdr_void,
99 (char *) NULL, (xdrproc_t) xdr_key_netstres,
100 (char *) &kres) &&
101 (kres.status == KEY_SUCCESS) &&
102 (kres.key_netstres_u.knet.st_priv_key[0] != 0))
103 {
104 /* avoid leaving secret key in memory */
105 memset (kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
106 return 1;
107 }
108 return 0;
109}
110#ifdef EXPORT_RPC_SYMBOLS
111libc_hidden_def (key_secretkey_is_set)
112#else
113libc_hidden_nolink_sunrpc (key_secretkey_is_set, GLIBC_2_1)
114#endif
115
116int
117key_encryptsession (char *remotename, des_block *deskey)
118{
119 cryptkeyarg arg;
120 cryptkeyres res;
121
122 arg.remotename = remotename;
123 arg.deskey = *deskey;
124 if (!key_call ((u_long) KEY_ENCRYPT, (xdrproc_t) xdr_cryptkeyarg,
125 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
126 (char *) &res))
127 return -1;
128
129 if (res.status != KEY_SUCCESS)
130 {
131 debug ("encrypt status is nonzero");
132 return -1;
133 }
134 *deskey = res.cryptkeyres_u.deskey;
135 return 0;
136}
137libc_hidden_nolink_sunrpc (key_encryptsession, GLIBC_2_1)
138
139int
140key_decryptsession (char *remotename, des_block *deskey)
141{
142 cryptkeyarg arg;
143 cryptkeyres res;
144
145 arg.remotename = remotename;
146 arg.deskey = *deskey;
147 if (!key_call ((u_long) KEY_DECRYPT, (xdrproc_t) xdr_cryptkeyarg,
148 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
149 (char *) &res))
150 return -1;
151 if (res.status != KEY_SUCCESS)
152 {
153 debug ("decrypt status is nonzero");
154 return -1;
155 }
156 *deskey = res.cryptkeyres_u.deskey;
157 return 0;
158}
159libc_hidden_nolink_sunrpc (key_decryptsession, GLIBC_2_1)
160
161int
162key_encryptsession_pk (char *remotename, netobj *remotekey,
163 des_block *deskey)
164{
165 cryptkeyarg2 arg;
166 cryptkeyres res;
167
168 arg.remotename = remotename;
169 arg.remotekey = *remotekey;
170 arg.deskey = *deskey;
171 if (!key_call ((u_long) KEY_ENCRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
172 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
173 (char *) &res))
174 return -1;
175
176 if (res.status != KEY_SUCCESS)
177 {
178 debug ("encrypt status is nonzero");
179 return -1;
180 }
181 *deskey = res.cryptkeyres_u.deskey;
182 return 0;
183}
184libc_hidden_nolink_sunrpc (key_encryptsession_pk, GLIBC_2_1)
185
186int
187key_decryptsession_pk (char *remotename, netobj *remotekey,
188 des_block *deskey)
189{
190 cryptkeyarg2 arg;
191 cryptkeyres res;
192
193 arg.remotename = remotename;
194 arg.remotekey = *remotekey;
195 arg.deskey = *deskey;
196 if (!key_call ((u_long) KEY_DECRYPT_PK, (xdrproc_t) xdr_cryptkeyarg2,
197 (char *) &arg, (xdrproc_t) xdr_cryptkeyres,
198 (char *) &res))
199 return -1;
200
201 if (res.status != KEY_SUCCESS)
202 {
203 debug ("decrypt status is nonzero");
204 return -1;
205 }
206 *deskey = res.cryptkeyres_u.deskey;
207 return 0;
208}
209libc_hidden_nolink_sunrpc (key_decryptsession_pk, GLIBC_2_1)
210
211int
212key_gendes (des_block *key)
213{
214 struct sockaddr_in sin;
215 CLIENT *client;
216 int socket;
217 enum clnt_stat stat;
218
219 sin.sin_family = AF_INET;
220 sin.sin_port = 0;
221 sin.sin_addr.s_addr = htonl (INADDR_LOOPBACK);
222 memset (sin.sin_zero, 0, sizeof (sin.sin_zero));
223 socket = RPC_ANYSOCK;
224 client = clntudp_bufcreate (&sin, (u_long) KEY_PROG, (u_long) KEY_VERS,
225 trytimeout, &socket, RPCSMALLMSGSIZE,
226 RPCSMALLMSGSIZE);
227 if (client == NULL)
228 return -1;
229
230 stat = clnt_call (client, KEY_GEN, (xdrproc_t) xdr_void, NULL,
231 (xdrproc_t) xdr_des_block, (caddr_t) key,
232 tottimeout);
233 clnt_destroy (client);
234 __close (socket);
235 if (stat != RPC_SUCCESS)
236 return -1;
237
238 return 0;
239}
240#ifdef EXPORT_RPC_SYMBOLS
241libc_hidden_def (key_gendes)
242#else
243libc_hidden_nolink_sunrpc (key_gendes, GLIBC_2_1)
244#endif
245
246int
247key_setnet (struct key_netstarg *arg)
248{
249 keystatus status;
250
251 if (!key_call ((u_long) KEY_NET_PUT, (xdrproc_t) xdr_key_netstarg,
252 (char *) arg,(xdrproc_t) xdr_keystatus,
253 (char *) &status))
254 return -1;
255
256 if (status != KEY_SUCCESS)
257 {
258 debug ("key_setnet status is nonzero");
259 return -1;
260 }
261 return 1;
262}
263libc_hidden_nolink_sunrpc (key_setnet, GLIBC_2_1)
264
265int
266key_get_conv (char *pkey, des_block *deskey)
267{
268 cryptkeyres res;
269
270 if (!key_call ((u_long) KEY_GET_CONV, (xdrproc_t) xdr_keybuf, pkey,
271 (xdrproc_t) xdr_cryptkeyres, (char *) &res))
272 return -1;
273
274 if (res.status != KEY_SUCCESS)
275 {
276 debug ("get_conv status is nonzero");
277 return -1;
278 }
279 *deskey = res.cryptkeyres_u.deskey;
280 return 0;
281}
282libc_hidden_nolink_sunrpc (key_get_conv, GLIBC_2_1)
283
284/*
285 * Hack to allow the keyserver to use AUTH_DES (for authenticated
286 * NIS+ calls, for example). The only functions that get called
287 * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
288 *
289 * The approach is to have the keyserver fill in pointers to local
290 * implementations of these functions, and to call those in key_call().
291 */
292
293cryptkeyres *(*__key_encryptsession_pk_LOCAL) (uid_t, char *);
294cryptkeyres *(*__key_decryptsession_pk_LOCAL) (uid_t, char *);
295des_block *(*__key_gendes_LOCAL) (uid_t, char *);
296#ifdef SHARED
297# ifndef EXPORT_RPC_SYMBOLS
298compat_symbol (libc, __key_encryptsession_pk_LOCAL,
299 __key_encryptsession_pk_LOCAL, GLIBC_2_1);
300compat_symbol (libc, __key_decryptsession_pk_LOCAL,
301 __key_decryptsession_pk_LOCAL, GLIBC_2_1);
302compat_symbol (libc, __key_gendes_LOCAL, __key_gendes_LOCAL, GLIBC_2_1);
303# endif
304#endif
305
306#ifndef SO_PASSCRED
307static int
308key_call_keyenvoy (u_long proc, xdrproc_t xdr_arg, char *arg,
309 xdrproc_t xdr_rslt, char *rslt)
310{
311 XDR xdrargs;
312 XDR xdrrslt;
313 FILE *fargs;
314 FILE *frslt;
315 sigset_t oldmask, mask;
316 int status;
317 int pid;
318 int success;
319 uid_t ruid;
320 uid_t euid;
321 static const char MESSENGER[] = "/usr/etc/keyenvoy";
322
323 success = 1;
324 sigemptyset (&mask);
325 sigaddset (&mask, SIGCHLD);
326 __sigprocmask (SIG_BLOCK, &mask, &oldmask);
327
328 /*
329 * We are going to exec a set-uid program which makes our effective uid
330 * zero, and authenticates us with our real uid. We need to make the
331 * effective uid be the real uid for the setuid program, and
332 * the real uid be the effective uid so that we can change things back.
333 */
334 euid = __geteuid ();
335 ruid = __getuid ();
336 __setreuid (euid, ruid);
337 pid = _openchild (MESSENGER, &fargs, &frslt);
338 __setreuid (ruid, euid);
339 if (pid < 0)
340 {
341 debug ("open_streams");
342 __sigprocmask (SIG_SETMASK, &oldmask, NULL);
343 return (0);
344 }
345 xdrstdio_create (&xdrargs, fargs, XDR_ENCODE);
346 xdrstdio_create (&xdrrslt, frslt, XDR_DECODE);
347
348 if (!xdr_u_long (&xdrargs, &proc) || !(*xdr_arg) (&xdrargs, arg))
349 {
350 debug ("xdr args");
351 success = 0;
352 }
353 fclose (fargs);
354
355 if (success && !(*xdr_rslt) (&xdrrslt, rslt))
356 {
357 debug ("xdr rslt");
358 success = 0;
359 }
360 fclose(frslt);
361
362 wait_again:
363 if (__wait4 (pid, &status, 0, NULL) < 0)
364 {
365 if (errno == EINTR)
366 goto wait_again;
367 debug ("wait4");
368 if (errno == ECHILD || errno == ESRCH)
369 perror ("wait");
370 else
371 success = 0;
372 }
373 else
374 if (status != 0)
375 {
376 debug ("wait4 1");
377 success = 0;
378 }
379 __sigprocmask (SIG_SETMASK, &oldmask, NULL);
380
381 return success;
382}
383#endif
384
385struct key_call_private {
386 CLIENT *client; /* Client handle */
387 pid_t pid; /* process-id at moment of creation */
388 uid_t uid; /* user-id at last authorization */
389};
390#define key_call_private_main RPC_THREAD_VARIABLE(key_call_private_s)
391__libc_lock_define_initialized (static, keycall_lock)
392
393/*
394 * Keep the handle cached. This call may be made quite often.
395 */
396static CLIENT *
397getkeyserv_handle (int vers)
398{
399 struct key_call_private *kcp = key_call_private_main;
400 struct timeval wait_time;
401 int fd;
402 struct sockaddr_un name;
403 socklen_t namelen = sizeof(struct sockaddr_un);
404
405#define TOTAL_TIMEOUT 30 /* total timeout talking to keyserver */
406#define TOTAL_TRIES 5 /* Number of tries */
407
408 if (kcp == (struct key_call_private *)NULL)
409 {
410 kcp = (struct key_call_private *)malloc (sizeof (*kcp));
411 if (kcp == (struct key_call_private *)NULL)
412 return (CLIENT *) NULL;
413
414 key_call_private_main = kcp;
415 kcp->client = NULL;
416 }
417
418 /* if pid has changed, destroy client and rebuild */
419 if (kcp->client != NULL && kcp->pid != __getpid ())
420 {
421 auth_destroy (kcp->client->cl_auth);
422 clnt_destroy (kcp->client);
423 kcp->client = NULL;
424 }
425
426 if (kcp->client != NULL)
427 {
428 /* if other side closed socket, build handle again */
429 clnt_control (kcp->client, CLGET_FD, (char *)&fd);
430 if (__getpeername (fd,(struct sockaddr *)&name,&namelen) == -1)
431 {
432 auth_destroy (kcp->client->cl_auth);
433 clnt_destroy (kcp->client);
434 kcp->client = NULL;
435 }
436 }
437
438 if (kcp->client != NULL)
439 {
440 /* if uid has changed, build client handle again */
441 if (kcp->uid != __geteuid ())
442 {
443 kcp->uid = __geteuid ();
444 auth_destroy (kcp->client->cl_auth);
445 kcp->client->cl_auth =
446 authunix_create ((char *)"", kcp->uid, 0, 0, NULL);
447 if (kcp->client->cl_auth == NULL)
448 {
449 clnt_destroy (kcp->client);
450 kcp->client = NULL;
451 return ((CLIENT *) NULL);
452 }
453 }
454 /* Change the version number to the new one */
455 clnt_control (kcp->client, CLSET_VERS, (void *)&vers);
456 return kcp->client;
457 }
458
459 if ((kcp->client == (CLIENT *) NULL))
460 /* Use the AF_UNIX transport */
461 kcp->client = clnt_create ("/var/run/keyservsock", KEY_PROG, vers, "unix");
462
463 if (kcp->client == (CLIENT *) NULL)
464 return (CLIENT *) NULL;
465
466 kcp->uid = __geteuid ();
467 kcp->pid = __getpid ();
468 kcp->client->cl_auth = authunix_create ((char *)"", kcp->uid, 0, 0, NULL);
469 if (kcp->client->cl_auth == NULL)
470 {
471 clnt_destroy (kcp->client);
472 kcp->client = NULL;
473 return (CLIENT *) NULL;
474 }
475
476 wait_time.tv_sec = TOTAL_TIMEOUT/TOTAL_TRIES;
477 wait_time.tv_usec = 0;
478 clnt_control (kcp->client, CLSET_RETRY_TIMEOUT,
479 (char *)&wait_time);
480 if (clnt_control (kcp->client, CLGET_FD, (char *)&fd))
481 __fcntl (fd, F_SETFD, FD_CLOEXEC); /* make it "close on exec" */
482
483 return kcp->client;
484}
485
486/* returns 0 on failure, 1 on success */
487static int
488key_call_socket (u_long proc, xdrproc_t xdr_arg, char *arg,
489 xdrproc_t xdr_rslt, char *rslt)
490{
491 CLIENT *clnt;
492 struct timeval wait_time;
493 int result = 0;
494
495 __libc_lock_lock (keycall_lock);
496 if ((proc == KEY_ENCRYPT_PK) || (proc == KEY_DECRYPT_PK) ||
497 (proc == KEY_NET_GET) || (proc == KEY_NET_PUT) ||
498 (proc == KEY_GET_CONV))
499 clnt = getkeyserv_handle(2); /* talk to version 2 */
500 else
501 clnt = getkeyserv_handle(1); /* talk to version 1 */
502
503 if (clnt != NULL)
504 {
505 wait_time.tv_sec = TOTAL_TIMEOUT;
506 wait_time.tv_usec = 0;
507
508 if (clnt_call (clnt, proc, xdr_arg, arg, xdr_rslt, rslt,
509 wait_time) == RPC_SUCCESS)
510 result = 1;
511 }
512
513 __libc_lock_unlock (keycall_lock);
514
515 return result;
516}
517
518
519/* returns 0 on failure, 1 on success */
520static int
521key_call (u_long proc, xdrproc_t xdr_arg, char *arg,
522 xdrproc_t xdr_rslt, char *rslt)
523{
524#ifndef SO_PASSCRED
525 static int use_keyenvoy;
526#endif
527
528 if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL)
529 {
530 cryptkeyres *res;
531 res = (*__key_encryptsession_pk_LOCAL) (__geteuid (), arg);
532 *(cryptkeyres *) rslt = *res;
533 return 1;
534 }
535 else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL)
536 {
537 cryptkeyres *res;
538 res = (*__key_decryptsession_pk_LOCAL) (__geteuid (), arg);
539 *(cryptkeyres *) rslt = *res;
540 return 1;
541 }
542 else if (proc == KEY_GEN && __key_gendes_LOCAL)
543 {
544 des_block *res;
545 res = (*__key_gendes_LOCAL) (__geteuid (), 0);
546 *(des_block *) rslt = *res;
547 return 1;
548 }
549
550#ifdef SO_PASSCRED
551 return key_call_socket (proc, xdr_arg, arg, xdr_rslt, rslt);
552#else
553 if (!use_keyenvoy)
554 {
555 if (key_call_socket (proc, xdr_arg, arg, xdr_rslt, rslt))
556 return 1;
557 use_keyenvoy = 1;
558 }
559 return key_call_keyenvoy (proc, xdr_arg, arg, xdr_rslt, rslt);
560#endif
561}
562
563void
564__rpc_thread_key_cleanup (void)
565{
566 struct key_call_private *kcp = RPC_THREAD_VARIABLE(key_call_private_s);
567
568 if (kcp) {
569 if (kcp->client) {
570 if (kcp->client->cl_auth)
571 auth_destroy (kcp->client->cl_auth);
572 clnt_destroy(kcp->client);
573 }
574 free (kcp);
575 }
576}
577