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 * auth_des.c, client-side implementation of DES authentication
33 */
34
35 #include <string.h>
36 #include <stdint.h>
37 #include <rpc/des_crypt.h>
38 #include <rpc/types.h>
39 #include <rpc/auth.h>
40 #include <rpc/auth_des.h>
41 #include <rpc/xdr.h>
42 #include <netinet/in.h> /* XXX: just to get htonl() and ntohl() */
43 #include <sys/socket.h>
44 #include <time.h>
45 #include <shlib-compat.h>
46
47 #define MILLION 1000000L
48 #define RTIME_TIMEOUT 5 /* seconds to wait for sync */
49
50 #define AUTH_PRIVATE(auth) (struct ad_private *) auth->ah_private
51 #define ALLOC(object_type) (object_type *) mem_alloc(sizeof(object_type))
52 #define FREE(ptr, size) mem_free((char *)(ptr), (int) size)
53 #define ATTEMPT(xdr_op) if (!(xdr_op)) return (FALSE)
54
55 #define debug(msg) /* printf("%s\n", msg) */
56
57
58 /*
59 * DES authenticator operations vector
60 */
61 static void authdes_nextverf (AUTH *);
62 static bool_t authdes_marshal (AUTH *, XDR *);
63 static bool_t authdes_validate (AUTH *, struct opaque_auth *);
64 static bool_t authdes_refresh (AUTH *);
65 static void authdes_destroy (AUTH *);
66 static bool_t synchronize (struct sockaddr *, struct rpc_timeval *);
67
68 static const struct auth_ops authdes_ops = {
69 authdes_nextverf,
70 authdes_marshal,
71 authdes_validate,
72 authdes_refresh,
73 authdes_destroy
74 };
75
76
77 /*
78 * This struct is pointed to by the ah_private field of an "AUTH *"
79 */
80 struct ad_private {
81 char *ad_fullname; /* client's full name */
82 u_int ad_fullnamelen; /* length of name, rounded up */
83 char *ad_servername; /* server's full name */
84 u_int ad_servernamelen; /* length of name, rounded up */
85 uint32_t ad_window; /* client specified window */
86 bool_t ad_dosync; /* synchronize? */
87 struct sockaddr ad_syncaddr; /* remote host to synch with */
88 struct rpc_timeval ad_timediff; /* server's time - client's time */
89 uint32_t ad_nickname; /* server's nickname for client */
90 struct authdes_cred ad_cred; /* storage for credential */
91 struct authdes_verf ad_verf; /* storage for verifier */
92 struct rpc_timeval ad_timestamp; /* timestamp sent */
93 des_block ad_xkey; /* encrypted conversation key */
94 u_char ad_pkey[1024]; /* Servers actual public key */
95 };
96
97
98 /*
99 * Create the client des authentication object
100 */
101 AUTH *
authdes_create(const char * servername,u_int window,struct sockaddr * syncaddr,des_block * ckey)102 authdes_create (const char *servername, u_int window,
103 struct sockaddr *syncaddr, des_block *ckey)
104 /* servername - network name of server */
105 /* window - time to live */
106 /* syncaddr - optional addr of host to sync with */
107 /* ckey - optional conversation key to use */
108 {
109 char pkey_data[1024];
110 netobj pkey;
111
112 if (!getpublickey (servername, pkey_data))
113 return NULL;
114
115 pkey.n_bytes = pkey_data;
116 pkey.n_len = strlen (pkey_data) + 1;
117 return authdes_pk_create (servername, &pkey, window, syncaddr, ckey);
118 }
119 #ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def(authdes_create)120 libc_hidden_def (authdes_create)
121 #else
122 libc_hidden_nolink_sunrpc (authdes_create, GLIBC_2_1)
123 #endif
124
125 AUTH *
126 authdes_pk_create (const char *servername, netobj *pkey, u_int window,
127 struct sockaddr *syncaddr, des_block *ckey)
128 {
129 AUTH *auth;
130 struct ad_private *ad;
131 char namebuf[MAXNETNAMELEN + 1];
132
133 /*
134 * Allocate everything now
135 */
136 auth = ALLOC (AUTH);
137 ad = ALLOC (struct ad_private);
138
139 if (auth == NULL || ad == NULL)
140 {
141 debug ("authdes_create: out of memory");
142 goto failed;
143 }
144
145 memset (ad, 0, sizeof (struct ad_private));
146 memcpy (ad->ad_pkey, pkey->n_bytes, pkey->n_len);
147 if (!getnetname (namebuf))
148 goto failed;
149 ad->ad_fullnamelen = RNDUP (strlen (namebuf));
150 ad->ad_fullname = mem_alloc (ad->ad_fullnamelen + 1);
151
152 ad->ad_servernamelen = strlen (servername);
153 ad->ad_servername = mem_alloc (ad->ad_servernamelen + 1);
154
155 if (ad->ad_fullname == NULL || ad->ad_servername == NULL)
156 {
157 debug ("authdes_create: out of memory");
158 goto failed;
159 }
160
161 /*
162 * Set up private data
163 */
164 memcpy (ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
165 memcpy (ad->ad_servername, servername, ad->ad_servernamelen + 1);
166 ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
167 if (syncaddr != NULL)
168 {
169 ad->ad_syncaddr = *syncaddr;
170 ad->ad_dosync = TRUE;
171 }
172 else
173 ad->ad_dosync = FALSE;
174
175 ad->ad_window = window;
176 if (ckey == NULL)
177 {
178 if (key_gendes (&auth->ah_key) < 0)
179 {
180 debug ("authdes_create: unable to gen conversation key");
181 goto failed;
182 }
183 }
184 else
185 auth->ah_key = *ckey;
186
187 /*
188 * Set up auth handle
189 */
190 auth->ah_cred.oa_flavor = AUTH_DES;
191 auth->ah_verf.oa_flavor = AUTH_DES;
192 auth->ah_ops = (struct auth_ops *) &authdes_ops;
193 auth->ah_private = (caddr_t) ad;
194
195 if (!authdes_refresh (auth))
196 goto failed;
197
198 return auth;
199
200 failed:
201 if (auth != NULL)
202 FREE (auth, sizeof (AUTH));
203 if (ad != NULL)
204 {
205 if (ad->ad_fullname != NULL)
206 FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
207 if (ad->ad_servername != NULL)
208 FREE (ad->ad_servername, ad->ad_servernamelen + 1);
209 FREE (ad, sizeof (struct ad_private));
210 }
211 return NULL;
212 }
213 #ifdef EXPORT_RPC_SYMBOLS
libc_hidden_def(authdes_pk_create)214 libc_hidden_def (authdes_pk_create)
215 #else
216 libc_hidden_nolink_sunrpc (authdes_pk_create, GLIBC_2_1)
217 #endif
218
219 /*
220 * Implement the five authentication operations
221 */
222
223
224 /*
225 * 1. Next Verifier
226 */
227 /*ARGSUSED */
228 static void
229 authdes_nextverf (AUTH *auth)
230 {
231 /* what the heck am I supposed to do??? */
232 }
233
234
235
236 /*
237 * 2. Marshal
238 */
239 static bool_t
authdes_marshal(AUTH * auth,XDR * xdrs)240 authdes_marshal (AUTH *auth, XDR *xdrs)
241 {
242 struct ad_private *ad = AUTH_PRIVATE (auth);
243 struct authdes_cred *cred = &ad->ad_cred;
244 struct authdes_verf *verf = &ad->ad_verf;
245 des_block cryptbuf[2];
246 des_block ivec;
247 int status;
248 int len;
249 register int32_t *ixdr;
250 struct timespec now;
251
252 /*
253 * Figure out the "time", accounting for any time difference
254 * with the server if necessary.
255 */
256 __clock_gettime (CLOCK_REALTIME, &now);
257 ad->ad_timestamp.tv_sec = now.tv_sec + ad->ad_timediff.tv_sec;
258 ad->ad_timestamp.tv_usec = (now.tv_nsec / 1000) + ad->ad_timediff.tv_usec;
259 if (ad->ad_timestamp.tv_usec >= MILLION)
260 {
261 ad->ad_timestamp.tv_usec -= MILLION;
262 ad->ad_timestamp.tv_sec += 1;
263 }
264
265 /*
266 * XDR the timestamp and possibly some other things, then
267 * encrypt them.
268 * XXX We have a real Year 2038 problem here.
269 */
270 ixdr = (int32_t *) cryptbuf;
271 IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_sec);
272 IXDR_PUT_INT32 (ixdr, ad->ad_timestamp.tv_usec);
273 if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
274 {
275 IXDR_PUT_U_INT32 (ixdr, ad->ad_window);
276 IXDR_PUT_U_INT32 (ixdr, ad->ad_window - 1);
277 ivec.key.high = ivec.key.low = 0;
278 status = cbc_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
279 2 * sizeof (des_block), DES_ENCRYPT | DES_HW, (char *) &ivec);
280 }
281 else
282 status = ecb_crypt ((char *) &auth->ah_key, (char *) cryptbuf,
283 sizeof (des_block), DES_ENCRYPT | DES_HW);
284
285 if (DES_FAILED (status))
286 {
287 debug ("authdes_marshal: DES encryption failure");
288 return FALSE;
289 }
290 ad->ad_verf.adv_xtimestamp = cryptbuf[0];
291 if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
292 {
293 ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
294 ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
295 }
296 else
297 {
298 ad->ad_cred.adc_nickname = ad->ad_nickname;
299 ad->ad_verf.adv_winverf = 0;
300 }
301
302 /*
303 * Serialize the credential and verifier into opaque
304 * authentication data.
305 */
306 if (ad->ad_cred.adc_namekind == ADN_FULLNAME)
307 len = ((1 + 1 + 2 + 1) * BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
308 else
309 len = (1 + 1) * BYTES_PER_XDR_UNIT;
310
311 if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
312 {
313 IXDR_PUT_INT32 (ixdr, AUTH_DES);
314 IXDR_PUT_U_INT32 (ixdr, len);
315 }
316 else
317 {
318 ATTEMPT (xdr_putint32 (xdrs, &auth->ah_cred.oa_flavor));
319 ATTEMPT (xdr_putint32 (xdrs, &len));
320 }
321 ATTEMPT (xdr_authdes_cred (xdrs, cred));
322
323 len = (2 + 1) * BYTES_PER_XDR_UNIT;
324 if ((ixdr = xdr_inline (xdrs, 2 * BYTES_PER_XDR_UNIT)) != NULL)
325 {
326 IXDR_PUT_INT32 (ixdr, AUTH_DES);
327 IXDR_PUT_U_INT32 (ixdr, len);
328 }
329 else
330 {
331 ATTEMPT (xdr_putint32 (xdrs, &auth->ah_verf.oa_flavor));
332 ATTEMPT (xdr_putint32 (xdrs, &len));
333 }
334 ATTEMPT (xdr_authdes_verf (xdrs, verf));
335
336 return TRUE;
337 }
338
339
340 /*
341 * 3. Validate
342 */
343 static bool_t
authdes_validate(AUTH * auth,struct opaque_auth * rverf)344 authdes_validate (AUTH *auth, struct opaque_auth *rverf)
345 {
346 struct ad_private *ad = AUTH_PRIVATE (auth);
347 struct authdes_verf verf;
348 int status;
349 register uint32_t *ixdr;
350
351 if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT)
352 return FALSE;
353
354 ixdr = (uint32_t *) rverf->oa_base;
355 verf.adv_xtimestamp.key.high = *ixdr++;
356 verf.adv_xtimestamp.key.low = *ixdr++;
357 verf.adv_int_u = *ixdr++; /* nickname not XDR'd ! */
358
359 /*
360 * Decrypt the timestamp
361 */
362 status = ecb_crypt ((char *) &auth->ah_key, (char *) &verf.adv_xtimestamp,
363 sizeof (des_block), DES_DECRYPT | DES_HW);
364
365 if (DES_FAILED (status))
366 {
367 debug ("authdes_validate: DES decryption failure");
368 return FALSE;
369 }
370
371 /*
372 * xdr the decrypted timestamp
373 */
374 ixdr = (uint32_t *) verf.adv_xtimestamp.c;
375 verf.adv_timestamp.tv_sec = IXDR_GET_U_INT32 (ixdr) + 1;
376 verf.adv_timestamp.tv_usec = IXDR_GET_U_INT32 (ixdr);
377
378 /*
379 * validate
380 */
381 if (memcmp ((char *) &ad->ad_timestamp, (char *) &verf.adv_timestamp,
382 sizeof (struct rpc_timeval)) != 0)
383 {
384 debug ("authdes_validate: verifier mismatch\n");
385 return FALSE;
386 }
387
388 /*
389 * We have a nickname now, let's use it
390 */
391 ad->ad_nickname = verf.adv_nickname;
392 ad->ad_cred.adc_namekind = ADN_NICKNAME;
393 return TRUE;
394 }
395
396 /*
397 * 4. Refresh
398 */
399 static bool_t
authdes_refresh(AUTH * auth)400 authdes_refresh (AUTH *auth)
401 {
402 netobj pkey;
403 struct ad_private *ad = AUTH_PRIVATE (auth);
404 struct authdes_cred *cred = &ad->ad_cred;
405
406 if (ad->ad_dosync && !synchronize (&ad->ad_syncaddr, &ad->ad_timediff))
407 {
408 /*
409 * Hope the clocks are synced!
410 */
411 ad->ad_timediff.tv_sec = ad->ad_timediff.tv_usec = 0;
412 debug ("authdes_refresh: unable to synchronize with server");
413 }
414 ad->ad_xkey = auth->ah_key;
415 pkey.n_bytes = (char *) (ad->ad_pkey);
416 pkey.n_len = strlen ((char *) ad->ad_pkey) + 1;
417 if (key_encryptsession_pk (ad->ad_servername, &pkey, &ad->ad_xkey) < 0)
418 {
419 debug ("authdes_create: unable to encrypt conversation key");
420 return FALSE;
421 }
422 cred->adc_fullname.key = ad->ad_xkey;
423 cred->adc_namekind = ADN_FULLNAME;
424 cred->adc_fullname.name = ad->ad_fullname;
425 return TRUE;
426 }
427
428 /*
429 * 5. Destroy
430 */
431 static void
authdes_destroy(AUTH * auth)432 authdes_destroy (AUTH *auth)
433 {
434 struct ad_private *ad = AUTH_PRIVATE (auth);
435
436 FREE (ad->ad_fullname, ad->ad_fullnamelen + 1);
437 FREE (ad->ad_servername, ad->ad_servernamelen + 1);
438 FREE (ad, sizeof (struct ad_private));
439 FREE (auth, sizeof (AUTH));
440 }
441
442 /*
443 * Synchronize with the server at the given address, that is,
444 * adjust timep to reflect the delta between our clocks
445 */
446 static bool_t
synchronize(struct sockaddr * syncaddr,struct rpc_timeval * timep)447 synchronize (struct sockaddr *syncaddr, struct rpc_timeval *timep)
448 {
449 struct timespec mytime;
450 struct rpc_timeval timeout;
451 long int myusec;
452
453 timeout.tv_sec = RTIME_TIMEOUT;
454 timeout.tv_usec = 0;
455 if (rtime ((struct sockaddr_in *) syncaddr, timep, &timeout) < 0)
456 return FALSE;
457
458 __clock_gettime (CLOCK_REALTIME, &mytime);
459 timep->tv_sec -= mytime.tv_sec;
460 myusec = mytime.tv_nsec / 1000;
461 if (myusec > timep->tv_usec)
462 {
463 timep->tv_sec -= 1;
464 timep->tv_usec += MILLION;
465 }
466 timep->tv_usec -= myusec;
467 return TRUE;
468 }
469