1/*
2 * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
3 * unrestricted use provided that this legend is included on all tape
4 * media and as a part of the software program in whole or part.  Users
5 * may copy or modify Sun RPC without charge, but are not authorized
6 * to license or distribute it to anyone else except as part of a product or
7 * program developed by the user.
8 *
9 * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
10 * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
11 * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
12 *
13 * Sun RPC is provided with no support and without any obligation on the
14 * part of Sun Microsystems, Inc. to assist in its use, correction,
15 * modification or enhancement.
16 *
17 * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
18 * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
19 * OR ANY PART THEREOF.
20 *
21 * In no event will Sun Microsystems, Inc. be liable for any lost revenue
22 * or profits or other special, indirect and consequential damages, even if
23 * Sun has been advised of the possibility of such damages.
24 *
25 * Sun Microsystems, Inc.
26 * 2550 Garcia Avenue
27 * Mountain View, California  94043
28 */
29/*
30 * Copyright (c) 1988 by Sun Microsystems, Inc.
31 */
32/*
33 * auth_des.c, client-side implementation of DES authentication
34 */
35
36#include "namespace.h"
37#include "reentrant.h"
38#include <err.h>
39#include <errno.h>
40#include <string.h>
41#include <stdlib.h>
42#include <unistd.h>
43#include <sys/cdefs.h>
44#include <rpc/des_crypt.h>
45#include <syslog.h>
46#include <rpc/types.h>
47#include <rpc/auth.h>
48#include <rpc/auth_des.h>
49#include <rpc/clnt.h>
50#include <rpc/xdr.h>
51#include <sys/socket.h>
52#undef NIS
53#include <rpcsvc/nis.h>
54#include "un-namespace.h"
55#include "mt_misc.h"
56
57#if defined(LIBC_SCCS) && !defined(lint)
58static char sccsid[] = 	"@(#)auth_des.c	2.2 88/07/29 4.0 RPCSRC; from 1.9 88/02/08 SMI";
59#endif
60#include <sys/cdefs.h>
61__FBSDID("$FreeBSD$");
62
63#define USEC_PER_SEC		1000000
64#define RTIME_TIMEOUT		5	/* seconds to wait for sync */
65
66#define AUTH_PRIVATE(auth)	(struct ad_private *) auth->ah_private
67#define ALLOC(object_type)	(object_type *) mem_alloc(sizeof(object_type))
68#define FREE(ptr, size)		mem_free((char *)(ptr), (int) size)
69#define ATTEMPT(xdr_op)		if (!(xdr_op)) return (FALSE)
70
71extern bool_t xdr_authdes_cred( XDR *, struct authdes_cred *);
72extern bool_t xdr_authdes_verf( XDR *, struct authdes_verf *);
73extern int key_encryptsession_pk();
74
75extern bool_t __rpc_get_time_offset(struct timeval *, nis_server *, char *,
76	char **, char **);
77
78/*
79 * DES authenticator operations vector
80 */
81static void	authdes_nextverf(AUTH *);
82static bool_t	authdes_marshal(AUTH *, XDR *);
83static bool_t	authdes_validate(AUTH *, struct opaque_auth *);
84static bool_t	authdes_refresh(AUTH *, void *);
85static void	authdes_destroy(AUTH *);
86
87static struct auth_ops *authdes_ops(void);
88
89/*
90 * This struct is pointed to by the ah_private field of an "AUTH *"
91 */
92struct ad_private {
93	char *ad_fullname; 		/* client's full name */
94	u_int ad_fullnamelen;		/* length of name, rounded up */
95	char *ad_servername; 		/* server's full name */
96	u_int ad_servernamelen;		/* length of name, rounded up */
97	u_int ad_window;	  	/* client specified window */
98	bool_t ad_dosync;		/* synchronize? */
99	struct netbuf ad_syncaddr;	/* remote host to synch with */
100	char *ad_timehost;		/* remote host to synch with */
101	struct timeval ad_timediff;	/* server's time - client's time */
102	u_int ad_nickname;		/* server's nickname for client */
103	struct authdes_cred ad_cred;	/* storage for credential */
104	struct authdes_verf ad_verf;	/* storage for verifier */
105	struct timeval ad_timestamp;	/* timestamp sent */
106	des_block ad_xkey;		/* encrypted conversation key */
107	u_char ad_pkey[1024];		/* Server's actual public key */
108	char *ad_netid;			/* Timehost netid */
109	char *ad_uaddr;			/* Timehost uaddr */
110	nis_server *ad_nis_srvr;	/* NIS+ server struct */
111};
112
113AUTH *authdes_pk_seccreate(const char *, netobj *, u_int, const char *,
114	const des_block *, nis_server *);
115
116/*
117 * documented version of authdes_seccreate
118 */
119/*
120	servername:	network name of server
121	win:		time to live
122	timehost:	optional hostname to sync with
123	ckey:		optional conversation key to use
124*/
125
126AUTH *
127authdes_seccreate(const char *servername, const u_int win,
128	const char *timehost, const des_block *ckey)
129{
130	u_char  pkey_data[1024];
131	netobj  pkey;
132	AUTH    *dummy;
133
134	if (! getpublickey(servername, (char *) pkey_data)) {
135		syslog(LOG_ERR,
136		    "authdes_seccreate: no public key found for %s",
137		    servername);
138		return (NULL);
139	}
140
141	pkey.n_bytes = (char *) pkey_data;
142	pkey.n_len = (u_int)strlen((char *)pkey_data) + 1;
143	dummy = authdes_pk_seccreate(servername, &pkey, win, timehost,
144	    ckey, NULL);
145	return (dummy);
146}
147
148/*
149 * Slightly modified version of authdessec_create which takes the public key
150 * of the server principal as an argument. This spares us a call to
151 * getpublickey() which in the nameserver context can cause a deadlock.
152 */
153AUTH *
154authdes_pk_seccreate(const char *servername, netobj *pkey, u_int window,
155	const char *timehost, const des_block *ckey, nis_server *srvr)
156{
157	AUTH *auth;
158	struct ad_private *ad;
159	char namebuf[MAXNETNAMELEN+1];
160
161	/*
162	 * Allocate everything now
163	 */
164	auth = ALLOC(AUTH);
165	if (auth == NULL) {
166		syslog(LOG_ERR, "authdes_pk_seccreate: out of memory");
167		return (NULL);
168	}
169	ad = ALLOC(struct ad_private);
170	if (ad == NULL) {
171		syslog(LOG_ERR, "authdes_pk_seccreate: out of memory");
172		goto failed;
173	}
174	ad->ad_fullname = ad->ad_servername = NULL; /* Sanity reasons */
175	ad->ad_timehost = NULL;
176	ad->ad_netid = NULL;
177	ad->ad_uaddr = NULL;
178	ad->ad_nis_srvr = NULL;
179	ad->ad_timediff.tv_sec = 0;
180	ad->ad_timediff.tv_usec = 0;
181	memcpy(ad->ad_pkey, pkey->n_bytes, pkey->n_len);
182	if (!getnetname(namebuf))
183		goto failed;
184	ad->ad_fullnamelen = RNDUP((u_int) strlen(namebuf));
185	ad->ad_fullname = (char *)mem_alloc(ad->ad_fullnamelen + 1);
186	ad->ad_servernamelen = strlen(servername);
187	ad->ad_servername = (char *)mem_alloc(ad->ad_servernamelen + 1);
188
189	if (ad->ad_fullname == NULL || ad->ad_servername == NULL) {
190		syslog(LOG_ERR, "authdes_seccreate: out of memory");
191		goto failed;
192	}
193	if (timehost != NULL) {
194		ad->ad_timehost = (char *)mem_alloc(strlen(timehost) + 1);
195		if (ad->ad_timehost == NULL) {
196			syslog(LOG_ERR, "authdes_seccreate: out of memory");
197			goto failed;
198		}
199		memcpy(ad->ad_timehost, timehost, strlen(timehost) + 1);
200		ad->ad_dosync = TRUE;
201	} else if (srvr != NULL) {
202		ad->ad_nis_srvr = srvr;	/* transient */
203		ad->ad_dosync = TRUE;
204	} else {
205		ad->ad_dosync = FALSE;
206	}
207	memcpy(ad->ad_fullname, namebuf, ad->ad_fullnamelen + 1);
208	memcpy(ad->ad_servername, servername, ad->ad_servernamelen + 1);
209	ad->ad_window = window;
210	if (ckey == NULL) {
211		if (key_gendes(&auth->ah_key) < 0) {
212			syslog(LOG_ERR,
213	    "authdes_seccreate: keyserv(1m) is unable to generate session key");
214			goto failed;
215		}
216	} else {
217		auth->ah_key = *ckey;
218	}
219
220	/*
221	 * Set up auth handle
222	 */
223	auth->ah_cred.oa_flavor = AUTH_DES;
224	auth->ah_verf.oa_flavor = AUTH_DES;
225	auth->ah_ops = authdes_ops();
226	auth->ah_private = (caddr_t)ad;
227
228	if (!authdes_refresh(auth, NULL)) {
229		goto failed;
230	}
231	ad->ad_nis_srvr = NULL; /* not needed any longer */
232	return (auth);
233
234failed:
235	if (auth)
236		FREE(auth, sizeof (AUTH));
237	if (ad) {
238		if (ad->ad_fullname)
239			FREE(ad->ad_fullname, ad->ad_fullnamelen + 1);
240		if (ad->ad_servername)
241			FREE(ad->ad_servername, ad->ad_servernamelen + 1);
242		if (ad->ad_timehost)
243			FREE(ad->ad_timehost, strlen(ad->ad_timehost) + 1);
244		if (ad->ad_netid)
245			FREE(ad->ad_netid, strlen(ad->ad_netid) + 1);
246		if (ad->ad_uaddr)
247			FREE(ad->ad_uaddr, strlen(ad->ad_uaddr) + 1);
248		FREE(ad, sizeof (struct ad_private));
249	}
250	return (NULL);
251}
252
253/*
254 * Implement the five authentication operations
255 */
256
257
258/*
259 * 1. Next Verifier
260 */
261/*ARGSUSED*/
262static void
263authdes_nextverf(AUTH *auth)
264{
265	/* what the heck am I supposed to do??? */
266}
267
268
269/*
270 * 2. Marshal
271 */
272static bool_t
273authdes_marshal(AUTH *auth, XDR *xdrs)
274{
275/* LINTED pointer alignment */
276	struct ad_private *ad = AUTH_PRIVATE(auth);
277	struct authdes_cred *cred = &ad->ad_cred;
278	struct authdes_verf *verf = &ad->ad_verf;
279	des_block cryptbuf[2];
280	des_block ivec;
281	int status;
282	int len;
283	rpc_inline_t *ixdr;
284
285	/*
286	 * Figure out the "time", accounting for any time difference
287	 * with the server if necessary.
288	 */
289	(void)gettimeofday(&ad->ad_timestamp, NULL);
290	ad->ad_timestamp.tv_sec += ad->ad_timediff.tv_sec;
291	ad->ad_timestamp.tv_usec += ad->ad_timediff.tv_usec;
292	while (ad->ad_timestamp.tv_usec >= USEC_PER_SEC) {
293		ad->ad_timestamp.tv_usec -= USEC_PER_SEC;
294		ad->ad_timestamp.tv_sec++;
295	}
296
297	/*
298	 * XDR the timestamp and possibly some other things, then
299	 * encrypt them.
300	 */
301	ixdr = (rpc_inline_t *)cryptbuf;
302	IXDR_PUT_INT32(ixdr, ad->ad_timestamp.tv_sec);
303	IXDR_PUT_INT32(ixdr, ad->ad_timestamp.tv_usec);
304	if (ad->ad_cred.adc_namekind == ADN_FULLNAME) {
305		IXDR_PUT_U_INT32(ixdr, ad->ad_window);
306		IXDR_PUT_U_INT32(ixdr, ad->ad_window - 1);
307		ivec.key.high = ivec.key.low = 0;
308		status = cbc_crypt((char *)&auth->ah_key, (char *)cryptbuf,
309			(u_int) 2 * sizeof (des_block),
310			DES_ENCRYPT | DES_HW, (char *)&ivec);
311	} else {
312		status = ecb_crypt((char *)&auth->ah_key, (char *)cryptbuf,
313			(u_int) sizeof (des_block),
314			DES_ENCRYPT | DES_HW);
315	}
316	if (DES_FAILED(status)) {
317		syslog(LOG_ERR, "authdes_marshal: DES encryption failure");
318		return (FALSE);
319	}
320	ad->ad_verf.adv_xtimestamp = cryptbuf[0];
321	if (ad->ad_cred.adc_namekind == ADN_FULLNAME) {
322		ad->ad_cred.adc_fullname.window = cryptbuf[1].key.high;
323		ad->ad_verf.adv_winverf = cryptbuf[1].key.low;
324	} else {
325		ad->ad_cred.adc_nickname = ad->ad_nickname;
326		ad->ad_verf.adv_winverf = 0;
327	}
328
329	/*
330	 * Serialize the credential and verifier into opaque
331	 * authentication data.
332	 */
333	if (ad->ad_cred.adc_namekind == ADN_FULLNAME) {
334		len = ((1 + 1 + 2 + 1)*BYTES_PER_XDR_UNIT + ad->ad_fullnamelen);
335	} else {
336		len = (1 + 1)*BYTES_PER_XDR_UNIT;
337	}
338
339	if ((ixdr = xdr_inline(xdrs, 2*BYTES_PER_XDR_UNIT))) {
340		IXDR_PUT_INT32(ixdr, AUTH_DES);
341		IXDR_PUT_INT32(ixdr, len);
342	} else {
343		ATTEMPT(xdr_putint32(xdrs, (int *)&auth->ah_cred.oa_flavor));
344		ATTEMPT(xdr_putint32(xdrs, &len));
345	}
346	ATTEMPT(xdr_authdes_cred(xdrs, cred));
347
348	len = (2 + 1)*BYTES_PER_XDR_UNIT;
349	if ((ixdr = xdr_inline(xdrs, 2*BYTES_PER_XDR_UNIT))) {
350		IXDR_PUT_INT32(ixdr, AUTH_DES);
351		IXDR_PUT_INT32(ixdr, len);
352	} else {
353		ATTEMPT(xdr_putint32(xdrs, (int *)&auth->ah_verf.oa_flavor));
354		ATTEMPT(xdr_putint32(xdrs, &len));
355	}
356	ATTEMPT(xdr_authdes_verf(xdrs, verf));
357	return (TRUE);
358}
359
360
361/*
362 * 3. Validate
363 */
364static bool_t
365authdes_validate(AUTH *auth, struct opaque_auth *rverf)
366{
367/* LINTED pointer alignment */
368	struct ad_private *ad = AUTH_PRIVATE(auth);
369	struct authdes_verf verf;
370	int status;
371	uint32_t *ixdr;
372	des_block buf;
373
374	if (rverf->oa_length != (2 + 1) * BYTES_PER_XDR_UNIT) {
375		return (FALSE);
376	}
377/* LINTED pointer alignment */
378	ixdr = (uint32_t *)rverf->oa_base;
379	buf.key.high = (uint32_t)*ixdr++;
380	buf.key.low = (uint32_t)*ixdr++;
381	verf.adv_int_u = (uint32_t)*ixdr++;
382
383	/*
384	 * Decrypt the timestamp
385	 */
386	status = ecb_crypt((char *)&auth->ah_key, (char *)&buf,
387		(u_int)sizeof (des_block), DES_DECRYPT | DES_HW);
388
389	if (DES_FAILED(status)) {
390		syslog(LOG_ERR, "authdes_validate: DES decryption failure");
391		return (FALSE);
392	}
393
394	/*
395	 * xdr the decrypted timestamp
396	 */
397/* LINTED pointer alignment */
398	ixdr = (uint32_t *)buf.c;
399	verf.adv_timestamp.tv_sec = IXDR_GET_INT32(ixdr) + 1;
400	verf.adv_timestamp.tv_usec = IXDR_GET_INT32(ixdr);
401
402	/*
403	 * validate
404	 */
405	if (bcmp((char *)&ad->ad_timestamp, (char *)&verf.adv_timestamp,
406		 sizeof(struct timeval)) != 0) {
407		syslog(LOG_DEBUG, "authdes_validate: verifier mismatch");
408		return (FALSE);
409	}
410
411	/*
412	 * We have a nickname now, let's use it
413	 */
414	ad->ad_nickname = verf.adv_nickname;
415	ad->ad_cred.adc_namekind = ADN_NICKNAME;
416	return (TRUE);
417}
418
419/*
420 * 4. Refresh
421 */
422/*ARGSUSED*/
423static bool_t
424authdes_refresh(AUTH *auth, void *dummy)
425{
426/* LINTED pointer alignment */
427	struct ad_private *ad = AUTH_PRIVATE(auth);
428	struct authdes_cred *cred = &ad->ad_cred;
429	int		ok;
430	netobj		pkey;
431
432	if (ad->ad_dosync) {
433                ok = __rpc_get_time_offset(&ad->ad_timediff, ad->ad_nis_srvr,
434		    ad->ad_timehost, &(ad->ad_uaddr),
435		    &(ad->ad_netid));
436		if (! ok) {
437			/*
438			 * Hope the clocks are synced!
439			 */
440			ad->ad_dosync = 0;
441			syslog(LOG_DEBUG,
442			    "authdes_refresh: unable to synchronize clock");
443		 }
444	}
445	ad->ad_xkey = auth->ah_key;
446	pkey.n_bytes = (char *)(ad->ad_pkey);
447	pkey.n_len = (u_int)strlen((char *)ad->ad_pkey) + 1;
448	if (key_encryptsession_pk(ad->ad_servername, &pkey, &ad->ad_xkey) < 0) {
449		syslog(LOG_INFO,
450		    "authdes_refresh: keyserv(1m) is unable to encrypt session key");
451		return (FALSE);
452	}
453	cred->adc_fullname.key = ad->ad_xkey;
454	cred->adc_namekind = ADN_FULLNAME;
455	cred->adc_fullname.name = ad->ad_fullname;
456	return (TRUE);
457}
458
459
460/*
461 * 5. Destroy
462 */
463static void
464authdes_destroy(AUTH *auth)
465{
466/* LINTED pointer alignment */
467	struct ad_private *ad = AUTH_PRIVATE(auth);
468
469	FREE(ad->ad_fullname, ad->ad_fullnamelen + 1);
470	FREE(ad->ad_servername, ad->ad_servernamelen + 1);
471	if (ad->ad_timehost)
472		FREE(ad->ad_timehost, strlen(ad->ad_timehost) + 1);
473	if (ad->ad_netid)
474		FREE(ad->ad_netid, strlen(ad->ad_netid) + 1);
475	if (ad->ad_uaddr)
476		FREE(ad->ad_uaddr, strlen(ad->ad_uaddr) + 1);
477	FREE(ad, sizeof (struct ad_private));
478	FREE(auth, sizeof(AUTH));
479}
480
481static struct auth_ops *
482authdes_ops(void)
483{
484	static struct auth_ops ops;
485
486	/* VARIABLES PROTECTED BY ops_lock: ops */
487
488	mutex_lock(&authdes_ops_lock);
489	if (ops.ah_nextverf == NULL) {
490		ops.ah_nextverf = authdes_nextverf;
491		ops.ah_marshal = authdes_marshal;
492		ops.ah_validate = authdes_validate;
493		ops.ah_refresh = authdes_refresh;
494		ops.ah_destroy = authdes_destroy;
495        }
496	mutex_unlock(&authdes_ops_lock);
497	return (&ops);
498}
499