xref: /netbsd-src/external/bsd/ipf/dist/ip_rpcb_pxy.c (revision bdc22b2e01993381dcefeff2bc9b56ca75a4235c)
1 /*	$NetBSD: ip_rpcb_pxy.c,v 1.2 2012/07/22 14:27:35 darrenr Exp $	*/
2 
3 /*
4  * Copyright (C) 2002-2012 by Ryan Beasley <ryanb@goddamnbastard.org>
5  *
6  * See the IPFILTER.LICENCE file for details on licencing.
7  */
8 /*
9  * Overview:
10  *   This is an in-kernel application proxy for Sun's RPCBIND (nee portmap)
11  *   protocol as defined in RFC1833.  It is far from complete, mostly
12  *   lacking in less-likely corner cases, but it's definitely functional.
13  *
14  *   Invocation:
15  *     rdr <int> <e_ip>/32 port <e_p> -> <i_ip> port <i_p> udp proxy rpcbu
16  *
17  *   If the host running IP Filter is the same as the RPC server, it's
18  *   perfectly legal for both the internal and external addresses and ports
19  *   to match.
20  *
21  *   When triggered by appropriate IP NAT rules, this proxy works by
22  *   examining data contained in received packets.  Requests and replies are
23  *   modified, NAT and state table entries created, etc., as necessary.
24  */
25 /*
26  * TODO / NOTES
27  *
28  *   o Must implement locking to protect proxy session data.
29  *   o Fragmentation isn't supported.
30  *   o Only supports UDP.
31  *   o Doesn't support multiple RPC records in a single request.
32  *   o Errors should be more fine-grained.  (e.g., malloc failure vs.
33  *     illegal RPCB request / reply)
34  *   o Even with the limit on the total amount of recorded transactions,
35  *     should there be a timeout on transaction removal?
36  *   o There is a potential collision between cloning, wildcard NAT and
37  *     state entries.  There should be an appr_getport routine for
38  *     to avoid this.
39  *   o The enclosed hack of STREAMS support is pretty sick and most likely
40  *     broken.
41  *
42  *	Id: ip_rpcb_pxy.c,v 1.1.1.2 2012/07/22 13:44:23 darrenr Exp $
43  */
44 #define	IPF_RPCB_PROXY
45 
46 /*
47  * Function prototypes
48  */
49 void	ipf_p_rpcb_main_load __P((void));
50 void	ipf_p_rpcb_main_unload __P((void));
51 int	ipf_p_rpcb_new __P((void *, fr_info_t *, ap_session_t *, nat_t *));
52 void	ipf_p_rpcb_del __P((ipf_main_softc_t *, ap_session_t *));
53 int	ipf_p_rpcb_in __P((void *, fr_info_t *, ap_session_t *, nat_t *));
54 int	ipf_p_rpcb_out __P((void *, fr_info_t *, ap_session_t *, nat_t *));
55 
56 static void	ipf_p_rpcb_flush __P((rpcb_session_t *));
57 static int	ipf_p_rpcb_decodereq __P((fr_info_t *, nat_t *,
58 	rpcb_session_t *, rpc_msg_t *));
59 static int	ipf_p_rpcb_skipauth __P((rpc_msg_t *, xdr_auth_t *, u_32_t **));
60 static int	ipf_p_rpcb_insert __P((rpcb_session_t *, rpcb_xact_t *));
61 static int	ipf_p_rpcb_xdrrpcb __P((rpc_msg_t *, u_32_t *, rpcb_args_t *));
62 static int	ipf_p_rpcb_getuaddr __P((rpc_msg_t *, xdr_uaddr_t *,
63 	u_32_t **));
64 static u_int	ipf_p_rpcb_atoi __P((char *));
65 static int	ipf_p_rpcb_modreq __P((fr_info_t *, nat_t *, rpc_msg_t *,
66 	mb_t *, u_int));
67 static int	ipf_p_rpcb_decoderep __P((fr_info_t *, nat_t *,
68 	rpcb_session_t *, rpc_msg_t *, rpcb_xact_t **));
69 static rpcb_xact_t *	ipf_p_rpcb_lookup __P((rpcb_session_t *, u_32_t));
70 static void	ipf_p_rpcb_deref __P((rpcb_session_t *, rpcb_xact_t *));
71 static int	ipf_p_rpcb_getproto __P((rpc_msg_t *, xdr_proto_t *,
72 	u_32_t **));
73 static int	ipf_p_rpcb_getnat __P((fr_info_t *, nat_t *, u_int, u_int));
74 static int	ipf_p_rpcb_modv3 __P((fr_info_t *, nat_t *, rpc_msg_t *,
75 	mb_t *, u_int));
76 static int	ipf_p_rpcb_modv4 __P((fr_info_t *, nat_t *, rpc_msg_t *,
77 	mb_t *, u_int));
78 static void     ipf_p_rpcb_fixlen __P((fr_info_t *, int));
79 
80 /*
81  * Global variables
82  */
83 static	frentry_t	rpcbfr;	/* Skeleton rule for reference by entities
84 				   this proxy creates. */
85 static	int	rpcbcnt;	/* Upper bound of allocated RPCB sessions. */
86 				/* XXX rpcbcnt still requires locking. */
87 
88 static	int	rpcb_proxy_init = 0;
89 
90 
91 /*
92  * Since rpc_msg contains only pointers, one should use this macro as a
93  * handy way to get to the goods.  (In case you're wondering about the name,
94  * this started as BYTEREF -> BREF -> B.)
95  */
96 #define	B(r)	(u_32_t)ntohl(*(r))
97 
98 /*
99  * Public subroutines
100  */
101 
102 /* -------------------------------------------------------------------- */
103 /* Function:    ipf_p_rpcb_main_load                                    */
104 /* Returns:     void                                                    */
105 /* Parameters:  (void)                                                  */
106 /*                                                                      */
107 /* Initialize the filter rule entry and session limiter.                */
108 /* -------------------------------------------------------------------- */
109 void
110 ipf_p_rpcb_main_load()
111 {
112 	rpcbcnt = 0;
113 
114 	bzero((char *)&rpcbfr, sizeof(rpcbfr));
115 	rpcbfr.fr_ref = 1;
116 	rpcbfr.fr_flags = FR_PASS|FR_QUICK|FR_KEEPSTATE;
117 	MUTEX_INIT(&rpcbfr.fr_lock, "ipf Sun RPCB proxy rule lock");
118 	rpcb_proxy_init = 1;
119 }
120 
121 /* -------------------------------------------------------------------- */
122 /* Function:    ipf_p_rpcb_main_unload                                  */
123 /* Returns:     void                                                    */
124 /* Parameters:  (void)                                                  */
125 /*                                                                      */
126 /* Destroy rpcbfr's mutex to avoid a lock leak.                         */
127 /* -------------------------------------------------------------------- */
128 void
129 ipf_p_rpcb_main_unload()
130 {
131 	if (rpcb_proxy_init == 1) {
132 		MUTEX_DESTROY(&rpcbfr.fr_lock);
133 		rpcb_proxy_init = 0;
134 	}
135 }
136 
137 /* --------------------------------------------------------------------	*/
138 /* Function:	ipf_p_rpcb_new						*/
139 /* Returns:	int - -1 == failure, 0 == success			*/
140 /* Parameters:	fin(I)	- pointer to packet information			*/
141 /*		aps(I)	- pointer to proxy session structure		*/
142 /*		nat(I)	- pointer to NAT session structure		*/
143 /*									*/
144 /* Allocate resources for per-session proxy structures.			*/
145 /* --------------------------------------------------------------------	*/
146 int
147 ipf_p_rpcb_new(arg, fin, aps, nat)
148 	void *arg;
149 	fr_info_t *fin;
150 	ap_session_t *aps;
151 	nat_t *nat;
152 {
153 	rpcb_session_t *rs;
154 
155 	nat = nat;	/* LINT */
156 
157 	if (fin->fin_v != 4)
158 		return -1;
159 
160 	KMALLOC(rs, rpcb_session_t *);
161 	if (rs == NULL)
162 		return(-1);
163 
164 	bzero((char *)rs, sizeof(*rs));
165 	MUTEX_INIT(&rs->rs_rxlock, "ipf Sun RPCB proxy session lock");
166 
167 	aps->aps_data = rs;
168 
169 	return(0);
170 }
171 
172 /* --------------------------------------------------------------------	*/
173 /* Function:	ipf_p_rpcb_del						*/
174 /* Returns:	void							*/
175 /* Parameters:	aps(I)	- pointer to proxy session structure		*/
176 /*									*/
177 /* Free up a session's list of RPCB requests.				*/
178 /* --------------------------------------------------------------------	*/
179 void
180 ipf_p_rpcb_del(softc, aps)
181 	ipf_main_softc_t *softc;
182 	ap_session_t *aps;
183 {
184 	rpcb_session_t *rs;
185 	rs = (rpcb_session_t *)aps->aps_data;
186 
187 	MUTEX_ENTER(&rs->rs_rxlock);
188 	ipf_p_rpcb_flush(rs);
189 	MUTEX_EXIT(&rs->rs_rxlock);
190 	MUTEX_DESTROY(&rs->rs_rxlock);
191 }
192 
193 /* --------------------------------------------------------------------	*/
194 /* Function:	ipf_p_rpcb_in						*/
195 /* Returns:	int - APR_ERR(1) == drop the packet, 			*/
196 /*		      APR_ERR(2) == kill the proxy session,		*/
197 /*		      else change in packet length (in bytes)		*/
198 /* Parameters:	fin(I)	- pointer to packet information			*/
199 /*		ip(I)	- pointer to packet header			*/
200 /*		aps(I)	- pointer to proxy session structure		*/
201 /*		nat(I)	- pointer to NAT session structure		*/
202 /*									*/
203 /* Given a presumed RPCB request, perform some minor tests and pass off */
204 /* for decoding.  Also pass packet off for a rewrite if necessary.	*/
205 /* --------------------------------------------------------------------	*/
206 int
207 ipf_p_rpcb_in(arg, fin, aps, nat)
208 	void *arg;
209 	fr_info_t *fin;
210 	ap_session_t *aps;
211 	nat_t *nat;
212 {
213 	rpc_msg_t rpcmsg, *rm;
214 	rpcb_session_t *rs;
215 	u_int off, dlen;
216 	mb_t *m;
217 	int rv;
218 
219 	/* Disallow fragmented or illegally short packets. */
220 	if ((fin->fin_flx & (FI_FRAG|FI_SHORT)) != 0)
221 		return(APR_ERR(1));
222 
223 	/* Perform basic variable initialization. */
224 	rs = (rpcb_session_t *)aps->aps_data;
225 
226 	m = fin->fin_m;
227 	off = (char *)fin->fin_dp - (char *)fin->fin_ip;
228 	off += sizeof(udphdr_t) + fin->fin_ipoff;
229 	dlen = fin->fin_dlen - sizeof(udphdr_t);
230 
231 	/* Disallow packets outside legal range for supported requests. */
232 	if ((dlen < RPCB_REQMIN) || (dlen > RPCB_REQMAX))
233 		return(APR_ERR(1));
234 
235 	/* Copy packet over to convenience buffer. */
236 	rm = &rpcmsg;
237 	bzero((char *)rm, sizeof(*rm));
238 	COPYDATA(m, off, dlen, (caddr_t)&rm->rm_msgbuf);
239 	rm->rm_buflen = dlen;
240 
241 	/* Send off to decode request. */
242 	rv = ipf_p_rpcb_decodereq(fin, nat, rs, rm);
243 
244 	switch(rv)
245 	{
246 	case -1:
247 		return(APR_ERR(1));
248 		/*NOTREACHED*/
249 		break;
250 	case 0:
251 		break;
252 	case 1:
253 		rv = ipf_p_rpcb_modreq(fin, nat, rm, m, off);
254 		break;
255 	default:
256 		/*CONSTANTCONDITION*/
257 		IPF_PANIC(1, ("illegal rv %d (ipf_p_rpcb_req)", rv));
258 	}
259 
260 	return(rv);
261 }
262 
263 /* --------------------------------------------------------------------	*/
264 /* Function:	ipf_p_rpcb_out						*/
265 /* Returns:	int - APR_ERR(1) == drop the packet, 			*/
266 /*		      APR_ERR(2) == kill the proxy session,		*/
267 /*		      else change in packet length (in bytes)		*/
268 /* Parameters:	fin(I)	- pointer to packet information			*/
269 /*		ip(I)	- pointer to packet header			*/
270 /*		aps(I)	- pointer to proxy session structure		*/
271 /*		nat(I)	- pointer to NAT session structure		*/
272 /*									*/
273 /* Given a presumed RPCB reply, perform some minor tests and pass off	*/
274 /* for decoding.  If the message indicates a successful request with	*/
275 /* valid addressing information, create NAT and state structures to	*/
276 /* allow direct communication between RPC client and server.		*/
277 /* --------------------------------------------------------------------	*/
278 int
279 ipf_p_rpcb_out(arg, fin, aps, nat)
280 	void *arg;
281 	fr_info_t *fin;
282 	ap_session_t *aps;
283 	nat_t *nat;
284 {
285 	rpc_msg_t rpcmsg, *rm;
286 	rpcb_session_t *rs;
287 	rpcb_xact_t *rx;
288 	u_int off, dlen;
289 	int rv, diff;
290 	mb_t *m;
291 
292 	/* Disallow fragmented or illegally short packets. */
293 	if ((fin->fin_flx & (FI_FRAG|FI_SHORT)) != 0)
294 		return(APR_ERR(1));
295 
296 	/* Perform basic variable initialization. */
297 	rs = (rpcb_session_t *)aps->aps_data;
298 	rx = NULL;
299 
300 	m = fin->fin_m;
301 	off = (char *)fin->fin_dp - (char *)fin->fin_ip;
302 	off += sizeof(udphdr_t) + fin->fin_ipoff;
303 	dlen = fin->fin_dlen - sizeof(udphdr_t);
304 	diff = 0;
305 
306 	/* Disallow packets outside legal range for supported requests. */
307 	if ((dlen < RPCB_REPMIN) || (dlen > RPCB_REPMAX))
308 		return(APR_ERR(1));
309 
310 	/* Copy packet over to convenience buffer. */
311 	rm = &rpcmsg;
312 	bzero((char *)rm, sizeof(*rm));
313 	COPYDATA(m, off, dlen, (caddr_t)&rm->rm_msgbuf);
314 	rm->rm_buflen = dlen;
315 
316 	rx = NULL;		/* XXX gcc */
317 
318 	/* Send off to decode reply. */
319 	rv = ipf_p_rpcb_decoderep(fin, nat, rs, rm, &rx);
320 
321 	switch(rv)
322 	{
323 	case -1: /* Bad packet */
324                 if (rx != NULL) {
325                         MUTEX_ENTER(&rs->rs_rxlock);
326                         ipf_p_rpcb_deref(rs, rx);
327                         MUTEX_EXIT(&rs->rs_rxlock);
328                 }
329 		return(APR_ERR(1));
330 		/*NOTREACHED*/
331 		break;
332 	case  0: /* Negative reply / request rejected */
333 		break;
334 	case  1: /* Positive reply */
335 		/*
336 		 * With the IP address embedded in a GETADDR(LIST) reply,
337 		 * we'll need to rewrite the packet in the very possible
338 		 * event that the internal & external addresses aren't the
339 		 * same.  (i.e., this box is either a router or rpcbind
340 		 * only listens on loopback.)
341 		 */
342 		if (nat->nat_odstaddr != nat->nat_ndstaddr) {
343 			if (rx->rx_type == RPCB_RES_STRING)
344 				diff = ipf_p_rpcb_modv3(fin, nat, rm, m, off);
345 			else if (rx->rx_type == RPCB_RES_LIST)
346 				diff = ipf_p_rpcb_modv4(fin, nat, rm, m, off);
347 		}
348 		break;
349 	default:
350 		/*CONSTANTCONDITION*/
351 		IPF_PANIC(1, ("illegal rv %d (ipf_p_rpcb_decoderep)", rv));
352 	}
353 
354 	if (rx != NULL) {
355                 MUTEX_ENTER(&rs->rs_rxlock);
356                 /* XXX Gross hack - I'm overloading the reference
357                  * counter to deal with both threads and retransmitted
358                  * requests.  One deref signals that this thread is
359                  * finished with rx, and the other signals that we've
360                  * processed its reply.
361                  */
362                 ipf_p_rpcb_deref(rs, rx);
363                 ipf_p_rpcb_deref(rs, rx);
364                 MUTEX_EXIT(&rs->rs_rxlock);
365 	}
366 
367 	return(diff);
368 }
369 
370 /*
371  * Private support subroutines
372  */
373 
374 /* --------------------------------------------------------------------	*/
375 /* Function:	ipf_p_rpcb_flush						*/
376 /* Returns:	void							*/
377 /* Parameters:	rs(I)	- pointer to RPCB session structure		*/
378 /*									*/
379 /* Simply flushes the list of outstanding transactions, if any.		*/
380 /* --------------------------------------------------------------------	*/
381 static void
382 ipf_p_rpcb_flush(rs)
383 	rpcb_session_t *rs;
384 {
385 	rpcb_xact_t *r1, *r2;
386 
387 	r1 = rs->rs_rxlist;
388 	if (r1 == NULL)
389 		return;
390 
391 	while (r1 != NULL) {
392 		r2 = r1;
393 		r1 = r1->rx_next;
394 		KFREE(r2);
395 	}
396 }
397 
398 /* --------------------------------------------------------------------	*/
399 /* Function:	ipf_p_rpcb_decodereq					*/
400 /* Returns:	int - -1 == bad request or critical failure,		*/
401 /*		       0 == request successfully decoded,		*/
402 /*		       1 == request successfully decoded; requires	*/
403 /*			    address rewrite/modification		*/
404 /* Parameters:	fin(I)	- pointer to packet information			*/
405 /*		nat(I)	- pointer to NAT session structure		*/
406 /*		rs(I)	- pointer to RPCB session structure		*/
407 /*		rm(I)	- pointer to RPC message structure		*/
408 /*									*/
409 /* Take a presumed RPCB request, decode it, and store the results in	*/
410 /* the transaction list.  If the internal target address needs to be	*/
411 /* modified, store its location in ptr.					*/
412 /* WARNING:  It's the responsibility of the caller to make sure there	*/
413 /* is enough room in rs_buf for the basic RPC message "preamble".	*/
414 /* --------------------------------------------------------------------	*/
415 static int
416 ipf_p_rpcb_decodereq(fin, nat, rs, rm)
417 	fr_info_t *fin;
418 	nat_t *nat;
419 	rpcb_session_t *rs;
420 	rpc_msg_t *rm;
421 {
422 	rpcb_args_t *ra;
423 	u_32_t xdr, *p;
424 	rpc_call_t *rc;
425 	rpcb_xact_t rx;
426 	int mod;
427 
428 	p = (u_32_t *)rm->rm_msgbuf;
429 	mod = 0;
430 
431 	bzero((char *)&rx, sizeof(rx));
432 	rc = &rm->rm_call;
433 
434 	rm->rm_xid = p;
435 	rx.rx_xid = B(p++);	/* Record this message's XID. */
436 
437 	/* Parse out and test the RPC header. */
438 	if ((B(p++) != RPCB_CALL) ||
439 	    (B(p++) != RPCB_MSG_VERSION) ||
440 	    (B(p++) != RPCB_PROG))
441 		return(-1);
442 
443 	/* Record the RPCB version and procedure. */
444 	rc->rc_vers = p++;
445 	rc->rc_proc = p++;
446 
447 	/* Bypass RPC authentication stuff. */
448 	if (ipf_p_rpcb_skipauth(rm, &rc->rc_authcred, &p) != 0)
449 		return(-1);
450 	if (ipf_p_rpcb_skipauth(rm, &rc->rc_authverf, &p) != 0)
451 		return(-1);
452 
453 	/* Compare RPCB version and procedure numbers. */
454 	switch(B(rc->rc_vers))
455 	{
456 	case 2:
457 		/* This proxy only supports PMAP_GETPORT. */
458 		if (B(rc->rc_proc) != RPCB_GETPORT)
459 			return(-1);
460 
461 		/* Portmap requests contain four 4 byte parameters. */
462 		if (RPCB_BUF_EQ(rm, p, 16) == 0)
463 			return(-1);
464 
465 		p += 2; /* Skip requested program and version numbers. */
466 
467 		/* Sanity check the requested protocol. */
468 		xdr = B(p);
469 		if (!(xdr == IPPROTO_UDP || xdr == IPPROTO_TCP))
470 			return(-1);
471 
472 		rx.rx_type = RPCB_RES_PMAP;
473 		rx.rx_proto = xdr;
474 		break;
475 	case 3:
476 	case 4:
477 		/* GETADDRLIST is exclusive to v4; GETADDR for v3 & v4 */
478 		switch(B(rc->rc_proc))
479 		{
480 		case RPCB_GETADDR:
481 			rx.rx_type = RPCB_RES_STRING;
482 			rx.rx_proto = (u_int)fin->fin_p;
483 			break;
484 		case RPCB_GETADDRLIST:
485 			if (B(rc->rc_vers) != 4)
486 				return(-1);
487 			rx.rx_type = RPCB_RES_LIST;
488 			break;
489 		default:
490 			return(-1);
491 		}
492 
493 		ra = &rc->rc_rpcbargs;
494 
495 		/* Decode the 'struct rpcb' request. */
496 		if (ipf_p_rpcb_xdrrpcb(rm, p, ra) != 0)
497 			return(-1);
498 
499 		/* Are the target address & port valid? */
500 		if ((ra->ra_maddr.xu_ip != nat->nat_ndstaddr) ||
501 		    (ra->ra_maddr.xu_port != nat->nat_ndport))
502 		    	return(-1);
503 
504 		/* Do we need to rewrite this packet? */
505 		if ((nat->nat_ndstaddr != nat->nat_odstaddr) ||
506 		    (nat->nat_ndport != nat->nat_odport))
507 		    	mod = 1;
508 		break;
509 	default:
510 		return(-1);
511 	}
512 
513         MUTEX_ENTER(&rs->rs_rxlock);
514 	if (ipf_p_rpcb_insert(rs, &rx) != 0) {
515                 MUTEX_EXIT(&rs->rs_rxlock);
516 		return(-1);
517 	}
518         MUTEX_EXIT(&rs->rs_rxlock);
519 
520 	return(mod);
521 }
522 
523 /* --------------------------------------------------------------------	*/
524 /* Function:	ipf_p_rpcb_skipauth					*/
525 /* Returns:	int -- -1 == illegal auth parameters (lengths)		*/
526 /*			0 == valid parameters, pointer advanced		*/
527 /* Parameters:	rm(I)	- pointer to RPC message structure		*/
528 /*		auth(I)	- pointer to RPC auth structure			*/
529 /*		buf(IO)	- pointer to location within convenience buffer	*/
530 /*									*/
531 /* Record auth data length & location of auth data, then advance past	*/
532 /* it.									*/
533 /* --------------------------------------------------------------------	*/
534 static int
535 ipf_p_rpcb_skipauth(rm, auth, buf)
536 	rpc_msg_t *rm;
537 	xdr_auth_t *auth;
538 	u_32_t **buf;
539 {
540 	u_32_t *p, xdr;
541 
542 	p = *buf;
543 
544 	/* Make sure we have enough space for expected fixed auth parms. */
545 	if (RPCB_BUF_GEQ(rm, p, 8) == 0)
546 		return(-1);
547 
548 	p++; /* We don't care about auth_flavor. */
549 
550 	auth->xa_string.xs_len = p;
551 	xdr = B(p++);		/* Length of auth_data */
552 
553 	/* Test for absurdity / illegality of auth_data length. */
554 	if ((XDRALIGN(xdr) < xdr) || (RPCB_BUF_GEQ(rm, p, XDRALIGN(xdr)) == 0))
555 		return(-1);
556 
557 	auth->xa_string.xs_str = (char *)p;
558 
559 	p += XDRALIGN(xdr);	/* Advance our location. */
560 
561 	*buf = (u_32_t *)p;
562 
563 	return(0);
564 }
565 
566 /* --------------------------------------------------------------------	*/
567 /* Function:	ipf_p_rpcb_insert					*/
568 /* Returns:	int -- -1 == list insertion failed,			*/
569 /*			0 == item successfully added			*/
570 /* Parameters:	rs(I)	- pointer to RPCB session structure		*/
571 /*		rx(I)	- pointer to RPCB transaction structure		*/
572 /* --------------------------------------------------------------------	*/
573 static int
574 ipf_p_rpcb_insert(rs, rx)
575 	rpcb_session_t *rs;
576 	rpcb_xact_t *rx;
577 {
578 	rpcb_xact_t *rxp;
579 
580 	rxp = ipf_p_rpcb_lookup(rs, rx->rx_xid);
581 	if (rxp != NULL) {
582                 ++rxp->rx_ref;
583 		return(0);
584         }
585 
586 	if (rpcbcnt == RPCB_MAXREQS)
587 		return(-1);
588 
589 	KMALLOC(rxp, rpcb_xact_t *);
590 	if (rxp == NULL)
591 		return(-1);
592 
593 	bcopy((char *)rx, (char *)rxp, sizeof(*rx));
594 
595 	if (rs->rs_rxlist != NULL)
596 		rs->rs_rxlist->rx_pnext = &rxp->rx_next;
597 
598 	rxp->rx_pnext = &rs->rs_rxlist;
599 	rxp->rx_next = rs->rs_rxlist;
600 	rs->rs_rxlist = rxp;
601 
602 	rxp->rx_ref = 1;
603 
604 	++rpcbcnt;
605 
606 	return(0);
607 }
608 
609 /* --------------------------------------------------------------------	*/
610 /* Function:	ipf_p_rpcb_xdrrpcb					*/
611 /* Returns:	int -- -1 == failure to properly decode the request	*/
612 /*			0 == rpcb successfully decoded			*/
613 /* Parameters:	rs(I)	- pointer to RPCB session structure		*/
614 /*		p(I)	- pointer to location within session buffer	*/
615 /*		rpcb(O)	- pointer to rpcb (xdr type) structure		*/
616 /*									*/
617 /* Decode a XDR encoded rpcb structure and record its contents in rpcb  */
618 /* within only the context of TCP/UDP over IP networks.			*/
619 /* --------------------------------------------------------------------	*/
620 static int
621 ipf_p_rpcb_xdrrpcb(rm, p, ra)
622 	rpc_msg_t *rm;
623 	u_32_t *p;
624 	rpcb_args_t *ra;
625 {
626 	if (!RPCB_BUF_GEQ(rm, p, 20))
627 		return(-1);
628 
629 	/* Bypass target program & version. */
630 	p += 2;
631 
632 	/* Decode r_netid.  Must be "tcp" or "udp". */
633 	if (ipf_p_rpcb_getproto(rm, &ra->ra_netid, &p) != 0)
634 		return(-1);
635 
636 	/* Decode r_maddr. */
637 	if (ipf_p_rpcb_getuaddr(rm, &ra->ra_maddr, &p) != 0)
638 		return(-1);
639 
640 	/* Advance to r_owner and make sure it's empty. */
641 	if (!RPCB_BUF_EQ(rm, p, 4) || (B(p) != 0))
642 		return(-1);
643 
644 	return(0);
645 }
646 
647 /* --------------------------------------------------------------------	*/
648 /* Function:	ipf_p_rpcb_getuaddr					*/
649 /* Returns:	int -- -1 == illegal string,				*/
650 /*			0 == string parsed; contents recorded		*/
651 /* Parameters:	rm(I)	- pointer to RPC message structure		*/
652 /*		xu(I)	- pointer to universal address structure	*/
653 /*		p(IO)	- pointer to location within message buffer	*/
654 /*									*/
655 /* Decode the IP address / port at p and record them in xu.		*/
656 /* --------------------------------------------------------------------	*/
657 static int
658 ipf_p_rpcb_getuaddr(rm, xu, p)
659 	rpc_msg_t *rm;
660 	xdr_uaddr_t *xu;
661 	u_32_t **p;
662 {
663 	char *c, *i, *b, *pp;
664 	u_int d, dd, l, t;
665 	char uastr[24];
666 
667 	/* Test for string length. */
668 	if (!RPCB_BUF_GEQ(rm, *p, 4))
669 		return(-1);
670 
671 	xu->xu_xslen = (*p)++;
672 	xu->xu_xsstr = (char *)*p;
673 
674 	/* Length check */
675 	l = B(xu->xu_xslen);
676 	if (l < 11 || l > 23 || !RPCB_BUF_GEQ(rm, *p, XDRALIGN(l)))
677 		return(-1);
678 
679 	/* Advance p */
680 	*(char **)p += XDRALIGN(l);
681 
682 	/* Copy string to local buffer & terminate C style */
683 	bcopy(xu->xu_xsstr, uastr, l);
684 	uastr[l] = '\0';
685 
686 	i = (char *)&xu->xu_ip;
687 	pp = (char *)&xu->xu_port;
688 
689 	/*
690 	 * Expected format: a.b.c.d.e.f where [a-d] correspond to bytes of
691 	 * an IP address and [ef] are the bytes of a L4 port.
692 	 */
693 	if (!(ISDIGIT(uastr[0]) && ISDIGIT(uastr[l-1])))
694 		return(-1);
695 	b = uastr;
696 	for (c = &uastr[1], d = 0, dd = 0; c < &uastr[l-1]; c++) {
697 		if (ISDIGIT(*c)) {
698 			dd = 0;
699 			continue;
700 		}
701 		if (*c == '.') {
702 			if (dd != 0)
703 				return(-1);
704 
705 			/* Check for ASCII byte. */
706 			*c = '\0';
707 			t = ipf_p_rpcb_atoi(b);
708 			if (t > 255)
709 				return(-1);
710 
711 			/* Aim b at beginning of the next byte. */
712 			b = c + 1;
713 
714 			/* Switch off IP addr vs port parsing. */
715 			if (d < 4)
716 				i[d++] = t & 0xff;
717 			else
718 				pp[d++ - 4] = t & 0xff;
719 
720 			dd = 1;
721 			continue;
722 		}
723 		return(-1);
724 	}
725 	if (d != 5) /* String must contain exactly 5 periods. */
726 		return(-1);
727 
728 	/* Handle the last byte (port low byte) */
729 	t = ipf_p_rpcb_atoi(b);
730 	if (t > 255)
731 		return(-1);
732 	pp[d - 4] = t & 0xff;
733 
734 	return(0);
735 }
736 
737 /* --------------------------------------------------------------------	*/
738 /* Function:	ipf_p_rpcb_atoi (XXX should be generic for all proxies)	*/
739 /* Returns:	int -- integer representation of supplied string	*/
740 /* Parameters:	ptr(I)	- input string					*/
741 /*									*/
742 /* Simple version of atoi(3) ripped from ip_rcmd_pxy.c.			*/
743 /* --------------------------------------------------------------------	*/
744 static u_int
745 ipf_p_rpcb_atoi(ptr)
746 	char *ptr;
747 {
748 	register char *s = ptr, c;
749 	register u_int i = 0;
750 
751 	while (((c = *s++) != '\0') && ISDIGIT(c)) {
752 		i *= 10;
753 		i += c - '0';
754 	}
755 	return i;
756 }
757 
758 /* --------------------------------------------------------------------	*/
759 /* Function:	ipf_p_rpcb_modreq					*/
760 /* Returns:	int -- change in datagram length			*/
761 /*			APR_ERR(2) - critical failure			*/
762 /* Parameters:	fin(I)	- pointer to packet information			*/
763 /*		nat(I)	- pointer to NAT session			*/
764 /*		rm(I)	- pointer to RPC message structure		*/
765 /*		m(I)	- pointer to mbuf chain				*/
766 /*		off(I)	- current offset within mbuf chain		*/
767 /*									*/
768 /* When external and internal addresses differ, we rewrite the former	*/
769 /* with the latter.  (This is exclusive to protocol versions 3 & 4).	*/
770 /* --------------------------------------------------------------------	*/
771 static int
772 ipf_p_rpcb_modreq(fin, nat, rm, m, off)
773 	fr_info_t *fin;
774 	nat_t *nat;
775 	rpc_msg_t *rm;
776 	mb_t *m;
777 	u_int off;
778 {
779 	u_int len, xlen, pos, bogo;
780 	rpcb_args_t *ra;
781 	char uaddr[24];
782 	udphdr_t *udp;
783 	char *i, *p;
784 	int diff;
785 
786 	ra = &rm->rm_call.rc_rpcbargs;
787 	i = (char *)&nat->nat_odstaddr;
788 	p = (char *)&nat->nat_odport;
789 
790 	/* Form new string. */
791 	bzero(uaddr, sizeof(uaddr)); /* Just in case we need padding. */
792 #if defined(SNPRINTF) && defined(_KERNEL)
793 	SNPRINTF(uaddr, sizeof(uaddr),
794 #else
795 	(void) sprintf(uaddr,
796 #endif
797 		       "%u.%u.%u.%u.%u.%u", i[0] & 0xff, i[1] & 0xff,
798 		       i[2] & 0xff, i[3] & 0xff, p[0] & 0xff, p[1] & 0xff);
799 	len = strlen(uaddr);
800 	xlen = XDRALIGN(len);
801 
802 	/* Determine mbuf offset to start writing to. */
803 	pos = (char *)ra->ra_maddr.xu_xslen - rm->rm_msgbuf;
804 	off += pos;
805 
806 	/* Write new string length. */
807 	bogo = htonl(len);
808 	COPYBACK(m, off, 4, (caddr_t)&bogo);
809 	off += 4;
810 
811 	/* Write new string. */
812 	COPYBACK(m, off, xlen, uaddr);
813 	off += xlen;
814 
815 	/* Write in zero r_owner. */
816 	bogo = 0;
817 	COPYBACK(m, off, 4, (caddr_t)&bogo);
818 
819 	/* Determine difference in data lengths. */
820 	diff = xlen - XDRALIGN(B(ra->ra_maddr.xu_xslen));
821 
822 	/*
823 	 * If our new string has a different length, make necessary
824 	 * adjustments.
825 	 */
826 	if (diff != 0) {
827 		udp = fin->fin_dp;
828 		udp->uh_ulen = htons(ntohs(udp->uh_ulen) + diff);
829 		fin->fin_plen += diff;
830 		fin->fin_ip->ip_len = htons(fin->fin_plen);
831 		fin->fin_dlen += diff;
832 		/* XXX Storage lengths. */
833 	}
834 
835 	return(diff);
836 }
837 
838 /* --------------------------------------------------------------------	*/
839 /* Function:	ipf_p_rpcb_decoderep					*/
840 /* Returns:	int - -1 == bad request or critical failure,		*/
841 /*		       0 == valid, negative reply			*/
842 /*		       1 == vaddlid, positive reply; needs no changes	*/
843 /* Parameters:	fin(I)	- pointer to packet information			*/
844 /*		nat(I)	- pointer to NAT session structure		*/
845 /*		rs(I)	- pointer to RPCB session structure		*/
846 /*		rm(I)	- pointer to RPC message structure		*/
847 /*		rxp(O)	- pointer to RPCB transaction structure		*/
848 /*									*/
849 /* Take a presumed RPCB reply, extract the XID, search for the original */
850 /* request information, and determine whether the request was accepted	*/
851 /* or rejected.  With a valid accepted reply, go ahead and create NAT	*/
852 /* and state entries, and finish up by rewriting the packet as 		*/
853 /* required.								*/
854 /*									*/
855 /* WARNING:  It's the responsibility of the caller to make sure there	*/
856 /* is enough room in rs_buf for the basic RPC message "preamble".	*/
857 /* --------------------------------------------------------------------	*/
858 static int
859 ipf_p_rpcb_decoderep(fin, nat, rs, rm, rxp)
860 	fr_info_t *fin;
861 	nat_t *nat;
862 	rpcb_session_t *rs;
863 	rpc_msg_t *rm;
864 	rpcb_xact_t **rxp;
865 {
866 	rpcb_listp_t *rl;
867 	rpcb_entry_t *re;
868 	rpcb_xact_t *rx;
869 	u_32_t xdr, *p;
870 	rpc_resp_t *rr;
871 	int rv, cnt;
872 
873 	p = (u_32_t *)rm->rm_msgbuf;
874 
875 	bzero((char *)&rx, sizeof(rx));
876 	rr = &rm->rm_resp;
877 
878 	rm->rm_xid = p;
879 	xdr = B(p++);		/* Record this message's XID. */
880 
881 	/* Lookup XID */
882         MUTEX_ENTER(&rs->rs_rxlock);
883 	if ((rx = ipf_p_rpcb_lookup(rs, xdr)) == NULL) {
884                 MUTEX_EXIT(&rs->rs_rxlock);
885 		return(-1);
886         }
887         ++rx->rx_ref;        /* per thread reference */
888         MUTEX_EXIT(&rs->rs_rxlock);
889 
890 	*rxp = rx;
891 
892 	/* Test call vs reply */
893 	if (B(p++) != RPCB_REPLY)
894 		return(-1);
895 
896 	/* Test reply_stat */
897 	switch(B(p++))
898 	{
899 	case RPCB_MSG_DENIED:
900 		return(0);
901 	case RPCB_MSG_ACCEPTED:
902 		break;
903 	default:
904 		return(-1);
905 	}
906 
907 	/* Bypass RPC authentication stuff. */
908 	if (ipf_p_rpcb_skipauth(rm, &rr->rr_authverf, &p) != 0)
909 		return(-1);
910 
911 	/* Test accept status */
912 	if (!RPCB_BUF_GEQ(rm, p, 4))
913 		return(-1);
914 	if (B(p++) != 0)
915 		return(0);
916 
917 	/* Parse out the expected reply */
918 	switch(rx->rx_type)
919 	{
920 	case RPCB_RES_PMAP:
921 		/* There must be only one 4 byte argument. */
922 		if (!RPCB_BUF_EQ(rm, p, 4))
923 			return(-1);
924 
925 		rr->rr_v2 = p;
926 		xdr = B(rr->rr_v2);
927 
928 		/* Reply w/ a 0 port indicates service isn't registered */
929 		if (xdr == 0)
930 			return(0);
931 
932 		/* Is the value sane? */
933 		if (xdr > 65535)
934 			return(-1);
935 
936 		/* Create NAT & state table entries. */
937 		if (ipf_p_rpcb_getnat(fin, nat, rx->rx_proto, (u_int)xdr) != 0)
938 			return(-1);
939 		break;
940 	case RPCB_RES_STRING:
941 		/* Expecting a XDR string; need 4 bytes for length */
942 		if (!RPCB_BUF_GEQ(rm, p, 4))
943 			return(-1);
944 
945 		rr->rr_v3.xu_str.xs_len = p++;
946 		rr->rr_v3.xu_str.xs_str = (char *)p;
947 
948 		xdr = B(rr->rr_v3.xu_xslen);
949 
950 		/* A null string indicates an unregistered service */
951 		if ((xdr == 0) && RPCB_BUF_EQ(rm, p, 0))
952 			return(0);
953 
954 		/* Decode the target IP address / port. */
955 		if (ipf_p_rpcb_getuaddr(rm, &rr->rr_v3, &p) != 0)
956 			return(-1);
957 
958 		/* Validate the IP address and port contained. */
959 		if (nat->nat_odstaddr != rr->rr_v3.xu_ip)
960 			return(-1);
961 
962 		/* Create NAT & state table entries. */
963 		if (ipf_p_rpcb_getnat(fin, nat, rx->rx_proto,
964 				     (u_int)rr->rr_v3.xu_port) != 0)
965 			return(-1);
966 		break;
967 	case RPCB_RES_LIST:
968 		if (!RPCB_BUF_GEQ(rm, p, 4))
969 			return(-1);
970 		/* rpcb_entry_list_ptr */
971 		switch(B(p))
972 		{
973 		case 0:
974 			return(0);
975 			/*NOTREACHED*/
976 			break;
977 		case 1:
978 			break;
979 		default:
980 			return(-1);
981 		}
982 		rl = &rr->rr_v4;
983 		rl->rl_list = p++;
984 		cnt = 0;
985 
986 		for(;;) {
987 			re = &rl->rl_entries[rl->rl_cnt];
988 			if (ipf_p_rpcb_getuaddr(rm, &re->re_maddr, &p) != 0)
989 				return(-1);
990 			if (ipf_p_rpcb_getproto(rm, &re->re_netid, &p) != 0)
991 				return(-1);
992 			/* re_semantics & re_pfamily length */
993 			if (!RPCB_BUF_GEQ(rm, p, 12))
994 				return(-1);
995 			p++; /* Skipping re_semantics. */
996 			xdr = B(p++);
997 			if ((xdr != 4) || strncmp((char *)p, "inet", 4))
998 				return(-1);
999 			p++;
1000 			if (ipf_p_rpcb_getproto(rm, &re->re_proto, &p) != 0)
1001 				return(-1);
1002 			if (!RPCB_BUF_GEQ(rm, p, 4))
1003 				return(-1);
1004 			re->re_more = p;
1005 			if (B(re->re_more) > 1) /* 0,1 only legal values */
1006 				return(-1);
1007 			++rl->rl_cnt;
1008 			++cnt;
1009 			if (B(re->re_more) == 0)
1010 				break;
1011 			/* Replies in  max out at 2; TCP and/or UDP */
1012 			if (cnt > 2)
1013 				return(-1);
1014 			p++;
1015 		}
1016 
1017 		for(rl->rl_cnt = 0; rl->rl_cnt < cnt; rl->rl_cnt++) {
1018 			re = &rl->rl_entries[rl->rl_cnt];
1019 			rv = ipf_p_rpcb_getnat(fin, nat,
1020 			                      re->re_proto.xp_proto,
1021 				              (u_int)re->re_maddr.xu_port);
1022 			if (rv != 0)
1023 				return(-1);
1024 		}
1025 		break;
1026 	default:
1027 		/*CONSTANTCONDITION*/
1028 		IPF_PANIC(1, ("illegal rx_type %d", rx->rx_type));
1029 	}
1030 
1031 	return(1);
1032 }
1033 
1034 /* --------------------------------------------------------------------	*/
1035 /* Function:	ipf_p_rpcb_lookup					*/
1036 /* Returns:	rpcb_xact_t * 	- NULL == no matching record,		*/
1037 /*				  else pointer to relevant entry	*/
1038 /* Parameters:	rs(I)	- pointer to RPCB session			*/
1039 /*		xid(I)	- XID to look for				*/
1040 /* --------------------------------------------------------------------	*/
1041 static rpcb_xact_t *
1042 ipf_p_rpcb_lookup(rs, xid)
1043 	rpcb_session_t *rs;
1044 	u_32_t xid;
1045 {
1046 	rpcb_xact_t *rx;
1047 
1048 	if (rs->rs_rxlist == NULL)
1049 		return(NULL);
1050 
1051 	for (rx = rs->rs_rxlist; rx != NULL; rx = rx->rx_next)
1052 		if (rx->rx_xid == xid)
1053 			break;
1054 
1055 	return(rx);
1056 }
1057 
1058 /* --------------------------------------------------------------------	*/
1059 /* Function:	ipf_p_rpcb_deref					        */
1060 /* Returns:	(void)							*/
1061 /* Parameters:	rs(I)	- pointer to RPCB session			*/
1062 /*		rx(I)	- pointer to RPC transaction struct to remove	*/
1063 /*              force(I) - indicates to delete entry regardless of      */
1064 /*                         reference count                              */
1065 /* Locking:	rs->rs_rxlock must be held write only			*/
1066 /*									*/
1067 /* Free the RPCB transaction record rx from the chain of entries.	*/
1068 /* --------------------------------------------------------------------	*/
1069 static void
1070 ipf_p_rpcb_deref(rs, rx)
1071 	rpcb_session_t *rs;
1072 	rpcb_xact_t *rx;
1073 {
1074 	rs = rs;	/* LINT */
1075 
1076 	if (rx == NULL)
1077 		return;
1078 
1079 	if (--rx->rx_ref != 0)
1080 		return;
1081 
1082 	if (rx->rx_next != NULL)
1083 		rx->rx_next->rx_pnext = rx->rx_pnext;
1084 
1085 	*rx->rx_pnext = rx->rx_next;
1086 
1087 	KFREE(rx);
1088 
1089 	--rpcbcnt;
1090 }
1091 
1092 /* --------------------------------------------------------------------	*/
1093 /* Function:	ipf_p_rpcb_getproto					*/
1094 /* Returns:	int - -1 == illegal protocol/netid,			*/
1095 /*		       0 == legal protocol/netid			*/
1096 /* Parameters:	rm(I)	- pointer to RPC message structure		*/
1097 /*		xp(I)	- pointer to netid structure			*/
1098 /*		p(IO)	- pointer to location within packet buffer	*/
1099 /* 									*/
1100 /* Decode netid/proto stored at p and record its numeric value.	 	*/
1101 /* --------------------------------------------------------------------	*/
1102 static int
1103 ipf_p_rpcb_getproto(rm, xp, p)
1104 	rpc_msg_t *rm;
1105 	xdr_proto_t *xp;
1106 	u_32_t **p;
1107 {
1108 	u_int len;
1109 
1110 	/* Must have 4 bytes for length & 4 bytes for "tcp" or "udp". */
1111 	if (!RPCB_BUF_GEQ(rm, p, 8))
1112 		return(-1);
1113 
1114 	xp->xp_xslen = (*p)++;
1115 	xp->xp_xsstr = (char *)*p;
1116 
1117 	/* Test the string length. */
1118 	len = B(xp->xp_xslen);
1119 	if (len != 3)
1120 	 	return(-1);
1121 
1122 	/* Test the actual string & record the protocol accordingly. */
1123 	if (!strncmp((char *)xp->xp_xsstr, "tcp\0", 4))
1124 		xp->xp_proto = IPPROTO_TCP;
1125 	else if (!strncmp((char *)xp->xp_xsstr, "udp\0", 4))
1126 		xp->xp_proto = IPPROTO_UDP;
1127 	else {
1128 		return(-1);
1129 	}
1130 
1131 	/* Advance past the string. */
1132 	(*p)++;
1133 
1134 	return(0);
1135 }
1136 
1137 /* --------------------------------------------------------------------	*/
1138 /* Function:	ipf_p_rpcb_getnat					*/
1139 /* Returns:	int -- -1 == failed to create table entries,		*/
1140 /*			0 == success					*/
1141 /* Parameters:	fin(I)	- pointer to packet information			*/
1142 /*		nat(I)	- pointer to NAT table entry			*/
1143 /*		proto(I) - transport protocol for new entries		*/
1144 /*		port(I)	- new port to use w/ wildcard table entries	*/
1145 /*									*/
1146 /* Create state and NAT entries to handle an anticipated connection	*/
1147 /* attempt between RPC client and server.				*/
1148 /* --------------------------------------------------------------------	*/
1149 static int
1150 ipf_p_rpcb_getnat(fin, nat, proto, port)
1151 	fr_info_t *fin;
1152 	nat_t *nat;
1153 	u_int proto;
1154 	u_int port;
1155 {
1156 	ipf_main_softc_t *softc = fin->fin_main_soft;
1157 	ipnat_t *ipn, ipnat;
1158 	tcphdr_t tcp;
1159 	ipstate_t *is;
1160 	fr_info_t fi;
1161 	nat_t *natl;
1162 	int nflags;
1163 
1164 	ipn = nat->nat_ptr;
1165 
1166 	/* Generate dummy fr_info */
1167 	bcopy((char *)fin, (char *)&fi, sizeof(fi));
1168 	fi.fin_out = 0;
1169 	fi.fin_p = proto;
1170 	fi.fin_sport = 0;
1171 	fi.fin_dport = port & 0xffff;
1172 	fi.fin_flx |= FI_IGNORE;
1173 	fi.fin_saddr = nat->nat_osrcaddr;
1174 	fi.fin_daddr = nat->nat_odstaddr;
1175 
1176 	bzero((char *)&tcp, sizeof(tcp));
1177 	tcp.th_dport = htons(port);
1178 
1179 	if (proto == IPPROTO_TCP) {
1180 		tcp.th_win = htons(8192);
1181 		TCP_OFF_A(&tcp, sizeof(tcphdr_t) >> 2);
1182 		fi.fin_dlen = sizeof(tcphdr_t);
1183 		tcp.th_flags = TH_SYN;
1184 		nflags = NAT_TCP;
1185 	} else {
1186 		fi.fin_dlen = sizeof(udphdr_t);
1187 		nflags = NAT_UDP;
1188 	}
1189 
1190 	nflags |= SI_W_SPORT|NAT_SEARCH;
1191 	fi.fin_dp = &tcp;
1192 	fi.fin_plen = fi.fin_hlen + fi.fin_dlen;
1193 
1194 	/*
1195 	 * Search for existing NAT & state entries.  Pay close attention to
1196 	 * mutexes / locks grabbed from lookup routines, as not doing so could
1197 	 * lead to bad things.
1198 	 *
1199 	 * If successful, fr_stlookup returns with ipf_state locked.  We have
1200 	 * no use for this lock, so simply unlock it if necessary.
1201 	 */
1202 	is = ipf_state_lookup(&fi, &tcp, NULL);
1203 	if (is != NULL) {
1204 		RWLOCK_EXIT(&softc->ipf_state);
1205 	}
1206 
1207 	RWLOCK_EXIT(&softc->ipf_nat);
1208 
1209 	WRITE_ENTER(&softc->ipf_nat);
1210 	natl = ipf_nat_inlookup(&fi, nflags, proto, fi.fin_src, fi.fin_dst);
1211 
1212 	if ((natl != NULL) && (is != NULL)) {
1213 		MUTEX_DOWNGRADE(&softc->ipf_nat);
1214 		return(0);
1215 	}
1216 
1217 	/* Slightly modify the following structures for actual use in creating
1218 	 * NAT and/or state entries.  We're primarily concerned with stripping
1219 	 * flags that may be detrimental to the creation process or simply
1220 	 * shouldn't be associated with a table entry.
1221 	 */
1222 	fi.fin_fr = &rpcbfr;
1223 	fi.fin_flx &= ~FI_IGNORE;
1224 	nflags &= ~NAT_SEARCH;
1225 
1226 	if (natl == NULL) {
1227 #ifdef USE_MUTEXES
1228 		ipf_nat_softc_t *softn = softc->ipf_nat_soft;
1229 #endif
1230 
1231 		/* XXX Since we're just copying the original ipn contents
1232 		 * back, would we be better off just sending a pointer to
1233 		 * the 'temp' copy off to nat_new instead?
1234 		 */
1235 		/* Generate template/bogus NAT rule. */
1236 		bcopy((char *)ipn, (char *)&ipnat, sizeof(ipnat));
1237 		ipn->in_flags = nflags & IPN_TCPUDP;
1238 		ipn->in_apr = NULL;
1239 		ipn->in_pr[0] = proto;
1240 		ipn->in_pr[1] = proto;
1241 		ipn->in_dpmin = fi.fin_dport;
1242 		ipn->in_dpmax = fi.fin_dport;
1243 		ipn->in_dpnext = fi.fin_dport;
1244 		ipn->in_space = 1;
1245 		ipn->in_ippip = 1;
1246 		if (ipn->in_flags & IPN_FILTER) {
1247 			ipn->in_scmp = 0;
1248 			ipn->in_dcmp = 0;
1249 		}
1250 		ipn->in_plabel = -1;
1251 
1252 		/* Create NAT entry.  return NULL if this fails. */
1253 		MUTEX_ENTER(&softn->ipf_nat_new);
1254 		natl = ipf_nat_add(&fi, ipn, NULL, nflags|SI_CLONE|NAT_SLAVE,
1255 			       NAT_INBOUND);
1256 		MUTEX_EXIT(&softn->ipf_nat_new);
1257 
1258 		bcopy((char *)&ipnat, (char *)ipn, sizeof(ipnat));
1259 
1260 		if (natl == NULL) {
1261 			MUTEX_DOWNGRADE(&softc->ipf_nat);
1262 			return(-1);
1263 		}
1264 
1265 		natl->nat_ptr = ipn;
1266 		fi.fin_saddr = natl->nat_nsrcaddr;
1267 		fi.fin_daddr = natl->nat_ndstaddr;
1268 		ipn->in_use++;
1269 		(void) ipf_nat_proto(&fi, natl, nflags);
1270 		MUTEX_ENTER(&natl->nat_lock);
1271 		ipf_nat_update(&fi, natl);
1272 		MUTEX_EXIT(&natl->nat_lock);
1273 	}
1274 	MUTEX_DOWNGRADE(&softc->ipf_nat);
1275 
1276 	if (is == NULL) {
1277 		/* Create state entry.  Return NULL if this fails. */
1278 		fi.fin_flx |= FI_NATED;
1279 		fi.fin_flx &= ~FI_STATE;
1280 		nflags &= NAT_TCPUDP;
1281 		nflags |= SI_W_SPORT|SI_CLONE;
1282 
1283 		if (ipf_state_add(softc, &fi, NULL, nflags) != 0) {
1284 			/*
1285 			 * XXX nat_delete is private to ip_nat.c.  Should
1286 			 * check w/ Darren about this one.
1287 			 *
1288 			 * nat_delete(natl, NL_EXPIRE);
1289 			 */
1290 			return(-1);
1291 		}
1292 	}
1293 
1294 	return(0);
1295 }
1296 
1297 /* --------------------------------------------------------------------	*/
1298 /* Function:	ipf_p_rpcb_modv3						*/
1299 /* Returns:	int -- change in packet length				*/
1300 /* Parameters:	fin(I)	- pointer to packet information			*/
1301 /*		nat(I)	- pointer to NAT session			*/
1302 /*		rm(I)	- pointer to RPC message structure		*/
1303 /*		m(I)	- pointer to mbuf chain				*/
1304 /*		off(I)	- offset within mbuf chain			*/
1305 /*									*/
1306 /* Write a new universal address string to this packet, adjusting	*/
1307 /* lengths as necessary.						*/
1308 /* --------------------------------------------------------------------	*/
1309 static int
1310 ipf_p_rpcb_modv3(fin, nat, rm, m, off)
1311 	fr_info_t *fin;
1312 	nat_t *nat;
1313 	rpc_msg_t *rm;
1314 	mb_t *m;
1315 	u_int off;
1316 {
1317 	u_int len, xlen, pos, bogo;
1318 	rpc_resp_t *rr;
1319 	char uaddr[24];
1320 	char *i, *p;
1321 	int diff;
1322 
1323 	rr = &rm->rm_resp;
1324 	i = (char *)&nat->nat_ndstaddr;
1325 	p = (char *)&rr->rr_v3.xu_port;
1326 
1327 	/* Form new string. */
1328 	bzero(uaddr, sizeof(uaddr)); /* Just in case we need padding. */
1329 #if defined(SNPRINTF) && defined(_KERNEL)
1330 	SNPRINTF(uaddr, sizeof(uaddr),
1331 #else
1332 	(void) sprintf(uaddr,
1333 #endif
1334 		       "%u.%u.%u.%u.%u.%u", i[0] & 0xff, i[1] & 0xff,
1335 		       i[2] & 0xff, i[3] & 0xff, p[0] & 0xff, p[1] & 0xff);
1336 	len = strlen(uaddr);
1337 	xlen = XDRALIGN(len);
1338 
1339 	/* Determine mbuf offset to write to. */
1340 	pos = (char *)rr->rr_v3.xu_xslen - rm->rm_msgbuf;
1341 	off += pos;
1342 
1343 	/* Write new string length. */
1344 	bogo = htonl(len);
1345 	COPYBACK(m, off, 4, (caddr_t)&bogo);
1346 	off += 4;
1347 
1348 	/* Write new string. */
1349 	COPYBACK(m, off, xlen, uaddr);
1350 
1351 	/* Determine difference in data lengths. */
1352 	diff = xlen - XDRALIGN(B(rr->rr_v3.xu_xslen));
1353 
1354 	/*
1355 	 * If our new string has a different length, make necessary
1356 	 * adjustments.
1357 	 */
1358 	if (diff != 0)
1359 		ipf_p_rpcb_fixlen(fin, diff);
1360 
1361 	return(diff);
1362 }
1363 
1364 /* --------------------------------------------------------------------	*/
1365 /* Function:	ipf_p_rpcb_modv4						*/
1366 /* Returns:	int -- change in packet length				*/
1367 /* Parameters:	fin(I)	- pointer to packet information			*/
1368 /*		nat(I)	- pointer to NAT session			*/
1369 /*		rm(I)	- pointer to RPC message structure		*/
1370 /*		m(I)	- pointer to mbuf chain				*/
1371 /*		off(I)	- offset within mbuf chain			*/
1372 /*									*/
1373 /* Write new rpcb_entry list, adjusting	lengths as necessary.		*/
1374 /* --------------------------------------------------------------------	*/
1375 static int
1376 ipf_p_rpcb_modv4(fin, nat, rm, m, off)
1377 	fr_info_t *fin;
1378 	nat_t *nat;
1379 	rpc_msg_t *rm;
1380 	mb_t *m;
1381 	u_int off;
1382 {
1383 	u_int len, xlen, pos, bogo;
1384 	rpcb_listp_t *rl;
1385 	rpcb_entry_t *re;
1386 	rpc_resp_t *rr;
1387 	char uaddr[24];
1388 	int diff, cnt;
1389 	char *i, *p;
1390 
1391 	diff = 0;
1392 	rr = &rm->rm_resp;
1393 	rl = &rr->rr_v4;
1394 
1395 	i = (char *)&nat->nat_ndstaddr;
1396 
1397 	/* Determine mbuf offset to write to. */
1398 	re = &rl->rl_entries[0];
1399 	pos = (char *)re->re_maddr.xu_xslen - rm->rm_msgbuf;
1400 	off += pos;
1401 
1402 	for (cnt = 0; cnt < rl->rl_cnt; cnt++) {
1403 		re = &rl->rl_entries[cnt];
1404 		p = (char *)&re->re_maddr.xu_port;
1405 
1406 		/* Form new string. */
1407 		bzero(uaddr, sizeof(uaddr)); /* Just in case we need
1408 						padding. */
1409 #if defined(SNPRINTF) && defined(_KERNEL)
1410 		SNPRINTF(uaddr, sizeof(uaddr),
1411 #else
1412 		(void) sprintf(uaddr,
1413 #endif
1414 			       "%u.%u.%u.%u.%u.%u", i[0] & 0xff,
1415 			       i[1] & 0xff, i[2] & 0xff, i[3] & 0xff,
1416 			       p[0] & 0xff, p[1] & 0xff);
1417 		len = strlen(uaddr);
1418 		xlen = XDRALIGN(len);
1419 
1420 		/* Write new string length. */
1421 		bogo = htonl(len);
1422 		COPYBACK(m, off, 4, (caddr_t)&bogo);
1423 		off += 4;
1424 
1425 		/* Write new string. */
1426 		COPYBACK(m, off, xlen, uaddr);
1427 		off += xlen;
1428 
1429 		/* Record any change in length. */
1430 		diff += xlen - XDRALIGN(B(re->re_maddr.xu_xslen));
1431 
1432 		/* If the length changed, copy back the rest of this entry. */
1433 		len = ((char *)re->re_more + 4) -
1434 		       (char *)re->re_netid.xp_xslen;
1435 		if (diff != 0) {
1436 			COPYBACK(m, off, len, (caddr_t)re->re_netid.xp_xslen);
1437 		}
1438 		off += len;
1439 	}
1440 
1441 	/*
1442 	 * If our new string has a different length, make necessary
1443 	 * adjustments.
1444 	 */
1445 	if (diff != 0)
1446 		ipf_p_rpcb_fixlen(fin, diff);
1447 
1448 	return(diff);
1449 }
1450 
1451 
1452 /* --------------------------------------------------------------------	*/
1453 /* Function:    ipf_p_rpcb_fixlen                                        */
1454 /* Returns:     (void)                                                  */
1455 /* Parameters:  fin(I)  - pointer to packet information                 */
1456 /*              len(I)  - change in packet length                       */
1457 /*                                                                      */
1458 /* Adjust various packet related lengths held in structure and packet   */
1459 /* header fields.                                                       */
1460 /* --------------------------------------------------------------------	*/
1461 static void
1462 ipf_p_rpcb_fixlen(fin, len)
1463         fr_info_t *fin;
1464         int len;
1465 {
1466         udphdr_t *udp;
1467 
1468         udp = fin->fin_dp;
1469         udp->uh_ulen = htons(ntohs(udp->uh_ulen) + len);
1470         fin->fin_plen += len;
1471         fin->fin_ip->ip_len = htons(fin->fin_plen);
1472         fin->fin_dlen += len;
1473 }
1474 
1475 #undef B
1476