xref: /freebsd/sys/rpc/svc_vc.c (revision 86390f9444433b00296741d03d069a587ad8e4bf)
1 /*	$NetBSD: svc_vc.c,v 1.7 2000/08/03 00:01:53 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 2009, Sun Microsystems, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are met:
9  * - Redistributions of source code must retain the above copyright notice,
10  *   this list of conditions and the following disclaimer.
11  * - Redistributions in binary form must reproduce the above copyright notice,
12  *   this list of conditions and the following disclaimer in the documentation
13  *   and/or other materials provided with the distribution.
14  * - Neither the name of Sun Microsystems, 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 "AS IS"
19  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
22  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
23  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
24  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
25  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
26  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
27  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
28  * POSSIBILITY OF SUCH DAMAGE.
29  */
30 
31 #if defined(LIBC_SCCS) && !defined(lint)
32 static char *sccsid2 = "@(#)svc_tcp.c 1.21 87/08/11 Copyr 1984 Sun Micro";
33 static char *sccsid = "@(#)svc_tcp.c	2.2 88/08/01 4.0 RPCSRC";
34 #endif
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 /*
39  * svc_vc.c, Server side for Connection Oriented based RPC.
40  *
41  * Actually implements two flavors of transporter -
42  * a tcp rendezvouser (a listner and connection establisher)
43  * and a record/tcp stream.
44  */
45 
46 #include <sys/param.h>
47 #include <sys/lock.h>
48 #include <sys/kernel.h>
49 #include <sys/malloc.h>
50 #include <sys/mbuf.h>
51 #include <sys/mutex.h>
52 #include <sys/proc.h>
53 #include <sys/protosw.h>
54 #include <sys/queue.h>
55 #include <sys/socket.h>
56 #include <sys/socketvar.h>
57 #include <sys/sx.h>
58 #include <sys/systm.h>
59 #include <sys/uio.h>
60 
61 #include <net/vnet.h>
62 
63 #include <netinet/tcp.h>
64 
65 #include <rpc/rpc.h>
66 
67 #include <rpc/krpc.h>
68 #include <rpc/rpc_com.h>
69 
70 #include <security/mac/mac_framework.h>
71 
72 static bool_t svc_vc_rendezvous_recv(SVCXPRT *, struct rpc_msg *,
73     struct sockaddr **, struct mbuf **);
74 static enum xprt_stat svc_vc_rendezvous_stat(SVCXPRT *);
75 static void svc_vc_rendezvous_destroy(SVCXPRT *);
76 static bool_t svc_vc_null(void);
77 static void svc_vc_destroy(SVCXPRT *);
78 static enum xprt_stat svc_vc_stat(SVCXPRT *);
79 static bool_t svc_vc_recv(SVCXPRT *, struct rpc_msg *,
80     struct sockaddr **, struct mbuf **);
81 static bool_t svc_vc_reply(SVCXPRT *, struct rpc_msg *,
82     struct sockaddr *, struct mbuf *);
83 static bool_t svc_vc_control(SVCXPRT *xprt, const u_int rq, void *in);
84 static bool_t svc_vc_rendezvous_control (SVCXPRT *xprt, const u_int rq,
85     void *in);
86 static void svc_vc_backchannel_destroy(SVCXPRT *);
87 static enum xprt_stat svc_vc_backchannel_stat(SVCXPRT *);
88 static bool_t svc_vc_backchannel_recv(SVCXPRT *, struct rpc_msg *,
89     struct sockaddr **, struct mbuf **);
90 static bool_t svc_vc_backchannel_reply(SVCXPRT *, struct rpc_msg *,
91     struct sockaddr *, struct mbuf *);
92 static bool_t svc_vc_backchannel_control(SVCXPRT *xprt, const u_int rq,
93     void *in);
94 static SVCXPRT *svc_vc_create_conn(SVCPOOL *pool, struct socket *so,
95     struct sockaddr *raddr);
96 static int svc_vc_accept(struct socket *head, struct socket **sop);
97 static int svc_vc_soupcall(struct socket *so, void *arg, int waitflag);
98 
99 static struct xp_ops svc_vc_rendezvous_ops = {
100 	.xp_recv =	svc_vc_rendezvous_recv,
101 	.xp_stat =	svc_vc_rendezvous_stat,
102 	.xp_reply =	(bool_t (*)(SVCXPRT *, struct rpc_msg *,
103 		struct sockaddr *, struct mbuf *))svc_vc_null,
104 	.xp_destroy =	svc_vc_rendezvous_destroy,
105 	.xp_control =	svc_vc_rendezvous_control
106 };
107 
108 static struct xp_ops svc_vc_ops = {
109 	.xp_recv =	svc_vc_recv,
110 	.xp_stat =	svc_vc_stat,
111 	.xp_reply =	svc_vc_reply,
112 	.xp_destroy =	svc_vc_destroy,
113 	.xp_control =	svc_vc_control
114 };
115 
116 static struct xp_ops svc_vc_backchannel_ops = {
117 	.xp_recv =	svc_vc_backchannel_recv,
118 	.xp_stat =	svc_vc_backchannel_stat,
119 	.xp_reply =	svc_vc_backchannel_reply,
120 	.xp_destroy =	svc_vc_backchannel_destroy,
121 	.xp_control =	svc_vc_backchannel_control
122 };
123 
124 /*
125  * Usage:
126  *	xprt = svc_vc_create(sock, send_buf_size, recv_buf_size);
127  *
128  * Creates, registers, and returns a (rpc) tcp based transporter.
129  * Once *xprt is initialized, it is registered as a transporter
130  * see (svc.h, xprt_register).  This routine returns
131  * a NULL if a problem occurred.
132  *
133  * The filedescriptor passed in is expected to refer to a bound, but
134  * not yet connected socket.
135  *
136  * Since streams do buffered io similar to stdio, the caller can specify
137  * how big the send and receive buffers are via the second and third parms;
138  * 0 => use the system default.
139  */
140 SVCXPRT *
141 svc_vc_create(SVCPOOL *pool, struct socket *so, size_t sendsize,
142     size_t recvsize)
143 {
144 	SVCXPRT *xprt;
145 	struct sockaddr* sa;
146 	int error;
147 
148 	SOCK_LOCK(so);
149 	if (so->so_state & (SS_ISCONNECTED|SS_ISDISCONNECTED)) {
150 		SOCK_UNLOCK(so);
151 		error = so->so_proto->pr_usrreqs->pru_peeraddr(so, &sa);
152 		if (error)
153 			return (NULL);
154 		xprt = svc_vc_create_conn(pool, so, sa);
155 		free(sa, M_SONAME);
156 		return (xprt);
157 	}
158 	SOCK_UNLOCK(so);
159 
160 	xprt = svc_xprt_alloc();
161 	sx_init(&xprt->xp_lock, "xprt->xp_lock");
162 	xprt->xp_pool = pool;
163 	xprt->xp_socket = so;
164 	xprt->xp_p1 = NULL;
165 	xprt->xp_p2 = NULL;
166 	xprt->xp_ops = &svc_vc_rendezvous_ops;
167 
168 	error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
169 	if (error) {
170 		goto cleanup_svc_vc_create;
171 	}
172 
173 	memcpy(&xprt->xp_ltaddr, sa, sa->sa_len);
174 	free(sa, M_SONAME);
175 
176 	xprt_register(xprt);
177 
178 	solisten(so, SOMAXCONN, curthread);
179 
180 	SOCKBUF_LOCK(&so->so_rcv);
181 	xprt->xp_upcallset = 1;
182 	soupcall_set(so, SO_RCV, svc_vc_soupcall, xprt);
183 	SOCKBUF_UNLOCK(&so->so_rcv);
184 
185 	return (xprt);
186 cleanup_svc_vc_create:
187 	if (xprt)
188 		svc_xprt_free(xprt);
189 	return (NULL);
190 }
191 
192 /*
193  * Create a new transport for a socket optained via soaccept().
194  */
195 SVCXPRT *
196 svc_vc_create_conn(SVCPOOL *pool, struct socket *so, struct sockaddr *raddr)
197 {
198 	SVCXPRT *xprt = NULL;
199 	struct cf_conn *cd = NULL;
200 	struct sockaddr* sa = NULL;
201 	struct sockopt opt;
202 	int one = 1;
203 	int error;
204 
205 	bzero(&opt, sizeof(struct sockopt));
206 	opt.sopt_dir = SOPT_SET;
207 	opt.sopt_level = SOL_SOCKET;
208 	opt.sopt_name = SO_KEEPALIVE;
209 	opt.sopt_val = &one;
210 	opt.sopt_valsize = sizeof(one);
211 	error = sosetopt(so, &opt);
212 	if (error) {
213 		return (NULL);
214 	}
215 
216 	if (so->so_proto->pr_protocol == IPPROTO_TCP) {
217 		bzero(&opt, sizeof(struct sockopt));
218 		opt.sopt_dir = SOPT_SET;
219 		opt.sopt_level = IPPROTO_TCP;
220 		opt.sopt_name = TCP_NODELAY;
221 		opt.sopt_val = &one;
222 		opt.sopt_valsize = sizeof(one);
223 		error = sosetopt(so, &opt);
224 		if (error) {
225 			return (NULL);
226 		}
227 	}
228 
229 	cd = mem_alloc(sizeof(*cd));
230 	cd->strm_stat = XPRT_IDLE;
231 
232 	xprt = svc_xprt_alloc();
233 	sx_init(&xprt->xp_lock, "xprt->xp_lock");
234 	xprt->xp_pool = pool;
235 	xprt->xp_socket = so;
236 	xprt->xp_p1 = cd;
237 	xprt->xp_p2 = NULL;
238 	xprt->xp_ops = &svc_vc_ops;
239 
240 	/*
241 	 * See http://www.connectathon.org/talks96/nfstcp.pdf - client
242 	 * has a 5 minute timer, server has a 6 minute timer.
243 	 */
244 	xprt->xp_idletimeout = 6 * 60;
245 
246 	memcpy(&xprt->xp_rtaddr, raddr, raddr->sa_len);
247 
248 	error = so->so_proto->pr_usrreqs->pru_sockaddr(so, &sa);
249 	if (error)
250 		goto cleanup_svc_vc_create;
251 
252 	memcpy(&xprt->xp_ltaddr, sa, sa->sa_len);
253 	free(sa, M_SONAME);
254 
255 	xprt_register(xprt);
256 
257 	SOCKBUF_LOCK(&so->so_rcv);
258 	xprt->xp_upcallset = 1;
259 	soupcall_set(so, SO_RCV, svc_vc_soupcall, xprt);
260 	SOCKBUF_UNLOCK(&so->so_rcv);
261 
262 	/*
263 	 * Throw the transport into the active list in case it already
264 	 * has some data buffered.
265 	 */
266 	sx_xlock(&xprt->xp_lock);
267 	xprt_active(xprt);
268 	sx_xunlock(&xprt->xp_lock);
269 
270 	return (xprt);
271 cleanup_svc_vc_create:
272 	if (xprt) {
273 		mem_free(xprt, sizeof(*xprt));
274 	}
275 	if (cd)
276 		mem_free(cd, sizeof(*cd));
277 	return (NULL);
278 }
279 
280 /*
281  * Create a new transport for a backchannel on a clnt_vc socket.
282  */
283 SVCXPRT *
284 svc_vc_create_backchannel(SVCPOOL *pool)
285 {
286 	SVCXPRT *xprt = NULL;
287 	struct cf_conn *cd = NULL;
288 
289 	cd = mem_alloc(sizeof(*cd));
290 	cd->strm_stat = XPRT_IDLE;
291 
292 	xprt = svc_xprt_alloc();
293 	sx_init(&xprt->xp_lock, "xprt->xp_lock");
294 	xprt->xp_pool = pool;
295 	xprt->xp_socket = NULL;
296 	xprt->xp_p1 = cd;
297 	xprt->xp_p2 = NULL;
298 	xprt->xp_ops = &svc_vc_backchannel_ops;
299 	return (xprt);
300 }
301 
302 /*
303  * This does all of the accept except the final call to soaccept. The
304  * caller will call soaccept after dropping its locks (soaccept may
305  * call malloc).
306  */
307 int
308 svc_vc_accept(struct socket *head, struct socket **sop)
309 {
310 	int error = 0;
311 	struct socket *so;
312 
313 	if ((head->so_options & SO_ACCEPTCONN) == 0) {
314 		error = EINVAL;
315 		goto done;
316 	}
317 #ifdef MAC
318 	error = mac_socket_check_accept(curthread->td_ucred, head);
319 	if (error != 0)
320 		goto done;
321 #endif
322 	ACCEPT_LOCK();
323 	if (TAILQ_EMPTY(&head->so_comp)) {
324 		ACCEPT_UNLOCK();
325 		error = EWOULDBLOCK;
326 		goto done;
327 	}
328 	so = TAILQ_FIRST(&head->so_comp);
329 	KASSERT(!(so->so_qstate & SQ_INCOMP), ("svc_vc_accept: so SQ_INCOMP"));
330 	KASSERT(so->so_qstate & SQ_COMP, ("svc_vc_accept: so not SQ_COMP"));
331 
332 	/*
333 	 * Before changing the flags on the socket, we have to bump the
334 	 * reference count.  Otherwise, if the protocol calls sofree(),
335 	 * the socket will be released due to a zero refcount.
336 	 * XXX might not need soref() since this is simpler than kern_accept.
337 	 */
338 	SOCK_LOCK(so);			/* soref() and so_state update */
339 	soref(so);			/* file descriptor reference */
340 
341 	TAILQ_REMOVE(&head->so_comp, so, so_list);
342 	head->so_qlen--;
343 	so->so_state |= (head->so_state & SS_NBIO);
344 	so->so_qstate &= ~SQ_COMP;
345 	so->so_head = NULL;
346 
347 	SOCK_UNLOCK(so);
348 	ACCEPT_UNLOCK();
349 
350 	*sop = so;
351 
352 	/* connection has been removed from the listen queue */
353 	KNOTE_UNLOCKED(&head->so_rcv.sb_sel.si_note, 0);
354 done:
355 	return (error);
356 }
357 
358 /*ARGSUSED*/
359 static bool_t
360 svc_vc_rendezvous_recv(SVCXPRT *xprt, struct rpc_msg *msg,
361     struct sockaddr **addrp, struct mbuf **mp)
362 {
363 	struct socket *so = NULL;
364 	struct sockaddr *sa = NULL;
365 	int error;
366 	SVCXPRT *new_xprt;
367 
368 	/*
369 	 * The socket upcall calls xprt_active() which will eventually
370 	 * cause the server to call us here. We attempt to accept a
371 	 * connection from the socket and turn it into a new
372 	 * transport. If the accept fails, we have drained all pending
373 	 * connections so we call xprt_inactive().
374 	 */
375 	sx_xlock(&xprt->xp_lock);
376 
377 	error = svc_vc_accept(xprt->xp_socket, &so);
378 
379 	if (error == EWOULDBLOCK) {
380 		/*
381 		 * We must re-test for new connections after taking
382 		 * the lock to protect us in the case where a new
383 		 * connection arrives after our call to accept fails
384 		 * with EWOULDBLOCK.
385 		 */
386 		ACCEPT_LOCK();
387 		if (TAILQ_EMPTY(&xprt->xp_socket->so_comp))
388 			xprt_inactive_self(xprt);
389 		ACCEPT_UNLOCK();
390 		sx_xunlock(&xprt->xp_lock);
391 		return (FALSE);
392 	}
393 
394 	if (error) {
395 		SOCKBUF_LOCK(&xprt->xp_socket->so_rcv);
396 		if (xprt->xp_upcallset) {
397 			xprt->xp_upcallset = 0;
398 			soupcall_clear(xprt->xp_socket, SO_RCV);
399 		}
400 		SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv);
401 		xprt_inactive_self(xprt);
402 		sx_xunlock(&xprt->xp_lock);
403 		return (FALSE);
404 	}
405 
406 	sx_xunlock(&xprt->xp_lock);
407 
408 	sa = 0;
409 	error = soaccept(so, &sa);
410 
411 	if (error) {
412 		/*
413 		 * XXX not sure if I need to call sofree or soclose here.
414 		 */
415 		if (sa)
416 			free(sa, M_SONAME);
417 		return (FALSE);
418 	}
419 
420 	/*
421 	 * svc_vc_create_conn will call xprt_register - we don't need
422 	 * to do anything with the new connection except derefence it.
423 	 */
424 	new_xprt = svc_vc_create_conn(xprt->xp_pool, so, sa);
425 	if (!new_xprt) {
426 		soclose(so);
427 	} else {
428 		SVC_RELEASE(new_xprt);
429 	}
430 
431 	free(sa, M_SONAME);
432 
433 	return (FALSE); /* there is never an rpc msg to be processed */
434 }
435 
436 /*ARGSUSED*/
437 static enum xprt_stat
438 svc_vc_rendezvous_stat(SVCXPRT *xprt)
439 {
440 
441 	return (XPRT_IDLE);
442 }
443 
444 static void
445 svc_vc_destroy_common(SVCXPRT *xprt)
446 {
447 	SOCKBUF_LOCK(&xprt->xp_socket->so_rcv);
448 	if (xprt->xp_upcallset) {
449 		xprt->xp_upcallset = 0;
450 		soupcall_clear(xprt->xp_socket, SO_RCV);
451 	}
452 	SOCKBUF_UNLOCK(&xprt->xp_socket->so_rcv);
453 
454 	sx_destroy(&xprt->xp_lock);
455 	if (xprt->xp_socket)
456 		(void)soclose(xprt->xp_socket);
457 
458 	if (xprt->xp_netid)
459 		(void) mem_free(xprt->xp_netid, strlen(xprt->xp_netid) + 1);
460 	svc_xprt_free(xprt);
461 }
462 
463 static void
464 svc_vc_rendezvous_destroy(SVCXPRT *xprt)
465 {
466 
467 	svc_vc_destroy_common(xprt);
468 }
469 
470 static void
471 svc_vc_destroy(SVCXPRT *xprt)
472 {
473 	struct cf_conn *cd = (struct cf_conn *)xprt->xp_p1;
474 
475 	svc_vc_destroy_common(xprt);
476 
477 	if (cd->mreq)
478 		m_freem(cd->mreq);
479 	if (cd->mpending)
480 		m_freem(cd->mpending);
481 	mem_free(cd, sizeof(*cd));
482 }
483 
484 static void
485 svc_vc_backchannel_destroy(SVCXPRT *xprt)
486 {
487 	struct cf_conn *cd = (struct cf_conn *)xprt->xp_p1;
488 	struct mbuf *m, *m2;
489 
490 	svc_xprt_free(xprt);
491 	m = cd->mreq;
492 	while (m != NULL) {
493 		m2 = m;
494 		m = m->m_nextpkt;
495 		m_freem(m2);
496 	}
497 	mem_free(cd, sizeof(*cd));
498 }
499 
500 /*ARGSUSED*/
501 static bool_t
502 svc_vc_control(SVCXPRT *xprt, const u_int rq, void *in)
503 {
504 	return (FALSE);
505 }
506 
507 static bool_t
508 svc_vc_rendezvous_control(SVCXPRT *xprt, const u_int rq, void *in)
509 {
510 
511 	return (FALSE);
512 }
513 
514 static bool_t
515 svc_vc_backchannel_control(SVCXPRT *xprt, const u_int rq, void *in)
516 {
517 
518 	return (FALSE);
519 }
520 
521 static enum xprt_stat
522 svc_vc_stat(SVCXPRT *xprt)
523 {
524 	struct cf_conn *cd;
525 
526 	cd = (struct cf_conn *)(xprt->xp_p1);
527 
528 	if (cd->strm_stat == XPRT_DIED)
529 		return (XPRT_DIED);
530 
531 	if (cd->mreq != NULL && cd->resid == 0 && cd->eor)
532 		return (XPRT_MOREREQS);
533 
534 	if (soreadable(xprt->xp_socket))
535 		return (XPRT_MOREREQS);
536 
537 	return (XPRT_IDLE);
538 }
539 
540 static enum xprt_stat
541 svc_vc_backchannel_stat(SVCXPRT *xprt)
542 {
543 	struct cf_conn *cd;
544 
545 	cd = (struct cf_conn *)(xprt->xp_p1);
546 
547 	if (cd->mreq != NULL)
548 		return (XPRT_MOREREQS);
549 
550 	return (XPRT_IDLE);
551 }
552 
553 /*
554  * If we have an mbuf chain in cd->mpending, try to parse a record from it,
555  * leaving the result in cd->mreq. If we don't have a complete record, leave
556  * the partial result in cd->mreq and try to read more from the socket.
557  */
558 static int
559 svc_vc_process_pending(SVCXPRT *xprt)
560 {
561 	struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
562 	struct socket *so = xprt->xp_socket;
563 	struct mbuf *m;
564 
565 	/*
566 	 * If cd->resid is non-zero, we have part of the
567 	 * record already, otherwise we are expecting a record
568 	 * marker.
569 	 */
570 	if (!cd->resid && cd->mpending) {
571 		/*
572 		 * See if there is enough data buffered to
573 		 * make up a record marker. Make sure we can
574 		 * handle the case where the record marker is
575 		 * split across more than one mbuf.
576 		 */
577 		size_t n = 0;
578 		uint32_t header;
579 
580 		m = cd->mpending;
581 		while (n < sizeof(uint32_t) && m) {
582 			n += m->m_len;
583 			m = m->m_next;
584 		}
585 		if (n < sizeof(uint32_t)) {
586 			so->so_rcv.sb_lowat = sizeof(uint32_t) - n;
587 			return (FALSE);
588 		}
589 		m_copydata(cd->mpending, 0, sizeof(header),
590 		    (char *)&header);
591 		header = ntohl(header);
592 		cd->eor = (header & 0x80000000) != 0;
593 		cd->resid = header & 0x7fffffff;
594 		m_adj(cd->mpending, sizeof(uint32_t));
595 	}
596 
597 	/*
598 	 * Start pulling off mbufs from cd->mpending
599 	 * until we either have a complete record or
600 	 * we run out of data. We use m_split to pull
601 	 * data - it will pull as much as possible and
602 	 * split the last mbuf if necessary.
603 	 */
604 	while (cd->mpending && cd->resid) {
605 		m = cd->mpending;
606 		if (cd->mpending->m_next
607 		    || cd->mpending->m_len > cd->resid)
608 			cd->mpending = m_split(cd->mpending,
609 			    cd->resid, M_WAITOK);
610 		else
611 			cd->mpending = NULL;
612 		if (cd->mreq)
613 			m_last(cd->mreq)->m_next = m;
614 		else
615 			cd->mreq = m;
616 		while (m) {
617 			cd->resid -= m->m_len;
618 			m = m->m_next;
619 		}
620 	}
621 
622 	/*
623 	 * Block receive upcalls if we have more data pending,
624 	 * otherwise report our need.
625 	 */
626 	if (cd->mpending)
627 		so->so_rcv.sb_lowat = INT_MAX;
628 	else
629 		so->so_rcv.sb_lowat =
630 		    imax(1, imin(cd->resid, so->so_rcv.sb_hiwat / 2));
631 	return (TRUE);
632 }
633 
634 static bool_t
635 svc_vc_recv(SVCXPRT *xprt, struct rpc_msg *msg,
636     struct sockaddr **addrp, struct mbuf **mp)
637 {
638 	struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
639 	struct uio uio;
640 	struct mbuf *m;
641 	struct socket* so = xprt->xp_socket;
642 	XDR xdrs;
643 	int error, rcvflag;
644 
645 	/*
646 	 * Serialise access to the socket and our own record parsing
647 	 * state.
648 	 */
649 	sx_xlock(&xprt->xp_lock);
650 
651 	for (;;) {
652 		/* If we have no request ready, check pending queue. */
653 		while (cd->mpending &&
654 		    (cd->mreq == NULL || cd->resid != 0 || !cd->eor)) {
655 			if (!svc_vc_process_pending(xprt))
656 				break;
657 		}
658 
659 		/* Process and return complete request in cd->mreq. */
660 		if (cd->mreq != NULL && cd->resid == 0 && cd->eor) {
661 
662 			xdrmbuf_create(&xdrs, cd->mreq, XDR_DECODE);
663 			cd->mreq = NULL;
664 
665 			/* Check for next request in a pending queue. */
666 			svc_vc_process_pending(xprt);
667 			if (cd->mreq == NULL || cd->resid != 0) {
668 				SOCKBUF_LOCK(&so->so_rcv);
669 				if (!soreadable(so))
670 					xprt_inactive_self(xprt);
671 				SOCKBUF_UNLOCK(&so->so_rcv);
672 			}
673 
674 			sx_xunlock(&xprt->xp_lock);
675 
676 			if (! xdr_callmsg(&xdrs, msg)) {
677 				XDR_DESTROY(&xdrs);
678 				return (FALSE);
679 			}
680 
681 			*addrp = NULL;
682 			*mp = xdrmbuf_getall(&xdrs);
683 			XDR_DESTROY(&xdrs);
684 
685 			return (TRUE);
686 		}
687 
688 		/*
689 		 * The socket upcall calls xprt_active() which will eventually
690 		 * cause the server to call us here. We attempt to
691 		 * read as much as possible from the socket and put
692 		 * the result in cd->mpending. If the read fails,
693 		 * we have drained both cd->mpending and the socket so
694 		 * we can call xprt_inactive().
695 		 */
696 		uio.uio_resid = 1000000000;
697 		uio.uio_td = curthread;
698 		m = NULL;
699 		rcvflag = MSG_DONTWAIT;
700 		error = soreceive(so, NULL, &uio, &m, NULL, &rcvflag);
701 
702 		if (error == EWOULDBLOCK) {
703 			/*
704 			 * We must re-test for readability after
705 			 * taking the lock to protect us in the case
706 			 * where a new packet arrives on the socket
707 			 * after our call to soreceive fails with
708 			 * EWOULDBLOCK.
709 			 */
710 			SOCKBUF_LOCK(&so->so_rcv);
711 			if (!soreadable(so))
712 				xprt_inactive_self(xprt);
713 			SOCKBUF_UNLOCK(&so->so_rcv);
714 			sx_xunlock(&xprt->xp_lock);
715 			return (FALSE);
716 		}
717 
718 		if (error) {
719 			SOCKBUF_LOCK(&so->so_rcv);
720 			if (xprt->xp_upcallset) {
721 				xprt->xp_upcallset = 0;
722 				soupcall_clear(so, SO_RCV);
723 			}
724 			SOCKBUF_UNLOCK(&so->so_rcv);
725 			xprt_inactive_self(xprt);
726 			cd->strm_stat = XPRT_DIED;
727 			sx_xunlock(&xprt->xp_lock);
728 			return (FALSE);
729 		}
730 
731 		if (!m) {
732 			/*
733 			 * EOF - the other end has closed the socket.
734 			 */
735 			xprt_inactive_self(xprt);
736 			cd->strm_stat = XPRT_DIED;
737 			sx_xunlock(&xprt->xp_lock);
738 			return (FALSE);
739 		}
740 
741 		if (cd->mpending)
742 			m_last(cd->mpending)->m_next = m;
743 		else
744 			cd->mpending = m;
745 	}
746 }
747 
748 static bool_t
749 svc_vc_backchannel_recv(SVCXPRT *xprt, struct rpc_msg *msg,
750     struct sockaddr **addrp, struct mbuf **mp)
751 {
752 	struct cf_conn *cd = (struct cf_conn *) xprt->xp_p1;
753 	struct ct_data *ct;
754 	struct mbuf *m;
755 	XDR xdrs;
756 
757 	sx_xlock(&xprt->xp_lock);
758 	ct = (struct ct_data *)xprt->xp_p2;
759 	if (ct == NULL) {
760 		sx_xunlock(&xprt->xp_lock);
761 		return (FALSE);
762 	}
763 	mtx_lock(&ct->ct_lock);
764 	m = cd->mreq;
765 	if (m == NULL) {
766 		xprt_inactive_self(xprt);
767 		mtx_unlock(&ct->ct_lock);
768 		sx_xunlock(&xprt->xp_lock);
769 		return (FALSE);
770 	}
771 	cd->mreq = m->m_nextpkt;
772 	mtx_unlock(&ct->ct_lock);
773 	sx_xunlock(&xprt->xp_lock);
774 
775 	xdrmbuf_create(&xdrs, m, XDR_DECODE);
776 	if (! xdr_callmsg(&xdrs, msg)) {
777 		XDR_DESTROY(&xdrs);
778 		return (FALSE);
779 	}
780 	*addrp = NULL;
781 	*mp = xdrmbuf_getall(&xdrs);
782 	XDR_DESTROY(&xdrs);
783 	return (TRUE);
784 }
785 
786 static bool_t
787 svc_vc_reply(SVCXPRT *xprt, struct rpc_msg *msg,
788     struct sockaddr *addr, struct mbuf *m)
789 {
790 	XDR xdrs;
791 	struct mbuf *mrep;
792 	bool_t stat = TRUE;
793 	int error;
794 
795 	/*
796 	 * Leave space for record mark.
797 	 */
798 	mrep = m_gethdr(M_WAITOK, MT_DATA);
799 	mrep->m_data += sizeof(uint32_t);
800 
801 	xdrmbuf_create(&xdrs, mrep, XDR_ENCODE);
802 
803 	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
804 	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
805 		if (!xdr_replymsg(&xdrs, msg))
806 			stat = FALSE;
807 		else
808 			xdrmbuf_append(&xdrs, m);
809 	} else {
810 		stat = xdr_replymsg(&xdrs, msg);
811 	}
812 
813 	if (stat) {
814 		m_fixhdr(mrep);
815 
816 		/*
817 		 * Prepend a record marker containing the reply length.
818 		 */
819 		M_PREPEND(mrep, sizeof(uint32_t), M_WAITOK);
820 		*mtod(mrep, uint32_t *) =
821 			htonl(0x80000000 | (mrep->m_pkthdr.len
822 				- sizeof(uint32_t)));
823 		error = sosend(xprt->xp_socket, NULL, NULL, mrep, NULL,
824 		    0, curthread);
825 		if (!error) {
826 			stat = TRUE;
827 		}
828 	} else {
829 		m_freem(mrep);
830 	}
831 
832 	XDR_DESTROY(&xdrs);
833 	xprt->xp_p2 = NULL;
834 
835 	return (stat);
836 }
837 
838 static bool_t
839 svc_vc_backchannel_reply(SVCXPRT *xprt, struct rpc_msg *msg,
840     struct sockaddr *addr, struct mbuf *m)
841 {
842 	struct ct_data *ct;
843 	XDR xdrs;
844 	struct mbuf *mrep;
845 	bool_t stat = TRUE;
846 	int error;
847 
848 	/*
849 	 * Leave space for record mark.
850 	 */
851 	mrep = m_gethdr(M_WAITOK, MT_DATA);
852 	mrep->m_data += sizeof(uint32_t);
853 
854 	xdrmbuf_create(&xdrs, mrep, XDR_ENCODE);
855 
856 	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
857 	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
858 		if (!xdr_replymsg(&xdrs, msg))
859 			stat = FALSE;
860 		else
861 			xdrmbuf_append(&xdrs, m);
862 	} else {
863 		stat = xdr_replymsg(&xdrs, msg);
864 	}
865 
866 	if (stat) {
867 		m_fixhdr(mrep);
868 
869 		/*
870 		 * Prepend a record marker containing the reply length.
871 		 */
872 		M_PREPEND(mrep, sizeof(uint32_t), M_WAITOK);
873 		*mtod(mrep, uint32_t *) =
874 			htonl(0x80000000 | (mrep->m_pkthdr.len
875 				- sizeof(uint32_t)));
876 		sx_xlock(&xprt->xp_lock);
877 		ct = (struct ct_data *)xprt->xp_p2;
878 		if (ct != NULL)
879 			error = sosend(ct->ct_socket, NULL, NULL, mrep, NULL,
880 			    0, curthread);
881 		else
882 			error = EPIPE;
883 		sx_xunlock(&xprt->xp_lock);
884 		if (!error) {
885 			stat = TRUE;
886 		}
887 	} else {
888 		m_freem(mrep);
889 	}
890 
891 	XDR_DESTROY(&xdrs);
892 
893 	return (stat);
894 }
895 
896 static bool_t
897 svc_vc_null()
898 {
899 
900 	return (FALSE);
901 }
902 
903 static int
904 svc_vc_soupcall(struct socket *so, void *arg, int waitflag)
905 {
906 	SVCXPRT *xprt = (SVCXPRT *) arg;
907 
908 	if (soreadable(xprt->xp_socket))
909 		xprt_active(xprt);
910 	return (SU_OK);
911 }
912 
913 #if 0
914 /*
915  * Get the effective UID of the sending process. Used by rpcbind, keyserv
916  * and rpc.yppasswdd on AF_LOCAL.
917  */
918 int
919 __rpc_get_local_uid(SVCXPRT *transp, uid_t *uid) {
920 	int sock, ret;
921 	gid_t egid;
922 	uid_t euid;
923 	struct sockaddr *sa;
924 
925 	sock = transp->xp_fd;
926 	sa = (struct sockaddr *)transp->xp_rtaddr;
927 	if (sa->sa_family == AF_LOCAL) {
928 		ret = getpeereid(sock, &euid, &egid);
929 		if (ret == 0)
930 			*uid = euid;
931 		return (ret);
932 	} else
933 		return (-1);
934 }
935 #endif
936