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
66
67#define KEY_TIMEOUT 5 /* per-try timeout in seconds */
68#define KEY_NRETRY 12 /* number of retries */
69
70#ifdef DEBUG
71#define debug(msg) (void) fprintf(stderr, "%s\n", msg);
72#else
73#define debug(msg)
74#endif /* DEBUG */
75
76/*
77 * Hack to allow the keyserver to use AUTH_DES (for authenticated
78 * NIS+ calls, for example). The only functions that get called
79 * are key_encryptsession_pk, key_decryptsession_pk, and key_gendes.
80 *
81 * The approach is to have the keyserver fill in pointers to local
82 * implementations of these functions, and to call those in key_call().
83 */
84
85cryptkeyres *(*__key_encryptsession_pk_LOCAL)() = 0;
86cryptkeyres *(*__key_decryptsession_pk_LOCAL)() = 0;
87des_block *(*__key_gendes_LOCAL)() = 0;
88
89static int key_call( u_long, xdrproc_t, char *, xdrproc_t, char * );
90
91int
92key_setsecret(secretkey)
93 const char *secretkey;
94{
95 keystatus status;
96
97 if (!key_call((u_long) KEY_SET, xdr_keybuf, (char *) secretkey,
98 xdr_keystatus, (char *)&status)) {
99 return (-1);
100 }
101 if (status != KEY_SUCCESS) {
102 debug("set status is nonzero");
103 return (-1);
104 }
105 return (0);
106}
107
108
109/* key_secretkey_is_set() returns 1 if the keyserver has a secret key
110 * stored for the caller's effective uid; it returns 0 otherwise
111 *
112 * N.B.: The KEY_NET_GET key call is undocumented. Applications shouldn't
113 * be using it, because it allows them to get the user's secret key.
114 */
115
116int
117key_secretkey_is_set(void)
118{
119 struct key_netstres kres;
120
121 memset((void*)&kres, 0, sizeof (kres));
122 if (key_call((u_long) KEY_NET_GET, xdr_void, (char *)NULL,
123 xdr_key_netstres, (char *) &kres) &&
124 (kres.status == KEY_SUCCESS) &&
125 (kres.key_netstres_u.knet.st_priv_key[0] != 0)) {
126 /* avoid leaving secret key in memory */
127 memset(kres.key_netstres_u.knet.st_priv_key, 0, HEXKEYBYTES);
128 return (1);
129 }
130 return (0);
131}
132
133int
134key_encryptsession_pk(remotename, remotekey, deskey)
135 char *remotename;
136 netobj *remotekey;
137 des_block *deskey;
138{
139 cryptkeyarg2 arg;
140 cryptkeyres res;
141
142 arg.remotename = remotename;
143 arg.remotekey = *remotekey;
144 arg.deskey = *deskey;
145 if (!key_call((u_long)KEY_ENCRYPT_PK, xdr_cryptkeyarg2, (char *)&arg,
146 xdr_cryptkeyres, (char *)&res)) {
147 return (-1);
148 }
149 if (res.status != KEY_SUCCESS) {
150 debug("encrypt status is nonzero");
151 return (-1);
152 }
153 *deskey = res.cryptkeyres_u.deskey;
154 return (0);
155}
156
157int
158key_decryptsession_pk(remotename, remotekey, deskey)
159 char *remotename;
160 netobj *remotekey;
161 des_block *deskey;
162{
163 cryptkeyarg2 arg;
164 cryptkeyres res;
165
166 arg.remotename = remotename;
167 arg.remotekey = *remotekey;
168 arg.deskey = *deskey;
169 if (!key_call((u_long)KEY_DECRYPT_PK, xdr_cryptkeyarg2, (char *)&arg,
170 xdr_cryptkeyres, (char *)&res)) {
171 return (-1);
172 }
173 if (res.status != KEY_SUCCESS) {
174 debug("decrypt status is nonzero");
175 return (-1);
176 }
177 *deskey = res.cryptkeyres_u.deskey;
178 return (0);
179}
180
181int
182key_encryptsession(remotename, deskey)
183 const char *remotename;
184 des_block *deskey;
185{
186 cryptkeyarg arg;
187 cryptkeyres res;
188
189 arg.remotename = (char *) remotename;
190 arg.deskey = *deskey;
191 if (!key_call((u_long)KEY_ENCRYPT, xdr_cryptkeyarg, (char *)&arg,
192 xdr_cryptkeyres, (char *)&res)) {
193 return (-1);
194 }
195 if (res.status != KEY_SUCCESS) {
196 debug("encrypt status is nonzero");
197 return (-1);
198 }
199 *deskey = res.cryptkeyres_u.deskey;
200 return (0);
201}
202
203int
204key_decryptsession(remotename, deskey)
205 const char *remotename;
206 des_block *deskey;
207{
208 cryptkeyarg arg;
209 cryptkeyres res;
210
211 arg.remotename = (char *) remotename;
212 arg.deskey = *deskey;
213 if (!key_call((u_long)KEY_DECRYPT, xdr_cryptkeyarg, (char *)&arg,
214 xdr_cryptkeyres, (char *)&res)) {
215 return (-1);
216 }
217 if (res.status != KEY_SUCCESS) {
218 debug("decrypt status is nonzero");
219 return (-1);
220 }
221 *deskey = res.cryptkeyres_u.deskey;
222 return (0);
223}
224
225int
226key_gendes(key)
227 des_block *key;
228{
229 if (!key_call((u_long)KEY_GEN, xdr_void, (char *)NULL,
230 xdr_des_block, (char *)key)) {
231 return (-1);
232 }
233 return (0);
234}
235
236int
237key_setnet(arg)
238struct key_netstarg *arg;
239{
240 keystatus status;
241
242
243 if (!key_call((u_long) KEY_NET_PUT, xdr_key_netstarg, (char *) arg,
244 xdr_keystatus, (char *) &status)){
245 return (-1);
246 }
247
248 if (status != KEY_SUCCESS) {
249 debug("key_setnet status is nonzero");
250 return (-1);
251 }
252 return (1);
253}
254
255
256int
257key_get_conv(pkey, deskey)
258 char *pkey;
259 des_block *deskey;
260{
261 cryptkeyres res;
262
263 if (!key_call((u_long) KEY_GET_CONV, xdr_keybuf, pkey,
264 xdr_cryptkeyres, (char *)&res)) {
265 return (-1);
266 }
267 if (res.status != KEY_SUCCESS) {
268 debug("get_conv status is nonzero");
269 return (-1);
270 }
271 *deskey = res.cryptkeyres_u.deskey;
272 return (0);
273}
274
275struct key_call_private {
276 CLIENT *client; /* Client handle */
277 pid_t pid; /* process-id at moment of creation */
278 uid_t uid; /* user-id at last authorization */
279};
280static struct key_call_private *key_call_private_main = NULL;
281
282static void
283key_call_destroy(void *vp)
284{
285 struct key_call_private *kcp = (struct key_call_private *)vp;
286
287 if (kcp) {
288 if (kcp->client)
289 clnt_destroy(kcp->client);
290 free(kcp);
291 }
292}
293
294/*
295 * Keep the handle cached. This call may be made quite often.
296 */
297static CLIENT *
298getkeyserv_handle(vers)
299int vers;
300{
301 void *localhandle;
302 struct netconfig *nconf;
303 struct netconfig *tpconf;
304 struct key_call_private *kcp = key_call_private_main;
305 struct timeval wait_time;
306 struct utsname u;
307 int main_thread;
308 int fd;
309 static thread_key_t key_call_key;
310 extern mutex_t tsd_lock;
311
312#define TOTAL_TIMEOUT 30 /* total timeout talking to keyserver */
313#define TOTAL_TRIES 5 /* Number of tries */
314
315 if ((main_thread = thr_main())) {
316 kcp = key_call_private_main;
317 } else {
318 if (key_call_key == 0) {
319 mutex_lock(&tsd_lock);
320 if (key_call_key == 0)
321 thr_keycreate(&key_call_key, key_call_destroy);
322 mutex_unlock(&tsd_lock);
323 }
324 kcp = (struct key_call_private *)thr_getspecific(key_call_key);
325 }
326 if (kcp == (struct key_call_private *)NULL) {
327 kcp = (struct key_call_private *)malloc(sizeof (*kcp));
328 if (kcp == (struct key_call_private *)NULL) {
329 return ((CLIENT *) NULL);
330 }
331 if (main_thread)
332 key_call_private_main = kcp;
333 else
334 thr_setspecific(key_call_key, (void *) kcp);
335 kcp->client = NULL;
336 }
337
338 /* if pid has changed, destroy client and rebuild */
339 if (kcp->client != NULL && kcp->pid != getpid()) {
340 clnt_destroy(kcp->client);
341 kcp->client = NULL;
342 }
343
344 if (kcp->client != NULL) {
345 /* if uid has changed, build client handle again */
346 if (kcp->uid != geteuid()) {
347 kcp->uid = geteuid();
348 auth_destroy(kcp->client->cl_auth);
349 kcp->client->cl_auth =
350 authsys_create("", kcp->uid, 0, 0, NULL);
351 if (kcp->client->cl_auth == NULL) {
352 clnt_destroy(kcp->client);
353 kcp->client = NULL;
354 return ((CLIENT *) NULL);
355 }
356 }
357 /* Change the version number to the new one */
358 clnt_control(kcp->client, CLSET_VERS, (void *)&vers);
359 return (kcp->client);
360 }
361 if (!(localhandle = setnetconfig())) {
362 return ((CLIENT *) NULL);
363 }
364 tpconf = NULL;
365#if defined(__FreeBSD__)
366 if (uname(&u) == -1)
367#else
368#if defined(i386)
369 if (_nuname(&u) == -1)
370#elif defined(sparc)
371 if (_uname(&u) == -1)
372#else
373#error Unknown architecture!
374#endif
375#endif
376 {
377 endnetconfig(localhandle);
378 return ((CLIENT *) NULL);
379 }
380 while ((nconf = getnetconfig(localhandle)) != NULL) {
381 if (strcmp(nconf->nc_protofmly, NC_LOOPBACK) == 0) {
382 /*
383 * We use COTS_ORD here so that the caller can
384 * find out immediately if the server is dead.
385 */
386 if (nconf->nc_semantics == NC_TPI_COTS_ORD) {
387 kcp->client = clnt_tp_create(u.nodename,
388 KEY_PROG, vers, nconf);
389 if (kcp->client)
390 break;
391 } else {
392 tpconf = nconf;
393 }
394 }
395 }
396 if ((kcp->client == (CLIENT *) NULL) && (tpconf))
397 /* Now, try the CLTS or COTS loopback transport */
398 kcp->client = clnt_tp_create(u.nodename,
399 KEY_PROG, vers, tpconf);
400 endnetconfig(localhandle);
401
402 if (kcp->client == (CLIENT *) NULL) {
403 return ((CLIENT *) NULL);
404 }
405 kcp->uid = geteuid();
406 kcp->pid = getpid();
407 kcp->client->cl_auth = authsys_create("", kcp->uid, 0, 0, NULL);
408 if (kcp->client->cl_auth == NULL) {
409 clnt_destroy(kcp->client);
410 kcp->client = NULL;
411 return ((CLIENT *) NULL);
412 }
413
414 wait_time.tv_sec = TOTAL_TIMEOUT/TOTAL_TRIES;
415 wait_time.tv_usec = 0;
416 (void) clnt_control(kcp->client, CLSET_RETRY_TIMEOUT,
417 (char *)&wait_time);
418 if (clnt_control(kcp->client, CLGET_FD, (char *)&fd))
419 _fcntl(fd, F_SETFD, 1); /* make it "close on exec" */
420
421 return (kcp->client);
422}
423
424/* returns 0 on failure, 1 on success */
425
426static int
427key_call(proc, xdr_arg, arg, xdr_rslt, rslt)
428 u_long proc;
429 xdrproc_t xdr_arg;
430 char *arg;
431 xdrproc_t xdr_rslt;
432 char *rslt;
433{
434 CLIENT *clnt;
435 struct timeval wait_time;
436
437 if (proc == KEY_ENCRYPT_PK && __key_encryptsession_pk_LOCAL) {
438 cryptkeyres *res;
439 res = (*__key_encryptsession_pk_LOCAL)(geteuid(), arg);
440 *(cryptkeyres*)rslt = *res;
441 return (1);
442 } else if (proc == KEY_DECRYPT_PK && __key_decryptsession_pk_LOCAL) {
443 cryptkeyres *res;
444 res = (*__key_decryptsession_pk_LOCAL)(geteuid(), arg);
445 *(cryptkeyres*)rslt = *res;
446 return (1);
447 } else if (proc == KEY_GEN && __key_gendes_LOCAL) {
448 des_block *res;
449 res = (*__key_gendes_LOCAL)(geteuid(), 0);
450 *(des_block*)rslt = *res;
451 return (1);
452 }
453
454 if ((proc == KEY_ENCRYPT_PK) || (proc == KEY_DECRYPT_PK) ||
455 (proc == KEY_NET_GET) || (proc == KEY_NET_PUT) ||
456 (proc == KEY_GET_CONV))
457 clnt = getkeyserv_handle(2); /* talk to version 2 */
458 else
459 clnt = getkeyserv_handle(1); /* talk to version 1 */
460
461 if (clnt == NULL) {
462 return (0);
463 }
464
465 wait_time.tv_sec = TOTAL_TIMEOUT;
466 wait_time.tv_usec = 0;
467
468 if (clnt_call(clnt, proc, xdr_arg, arg, xdr_rslt, rslt,
469 wait_time) == RPC_SUCCESS) {
470 return (1);
471 } else {
472 return (0);
473 }
474}
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