1 /* $NetBSD: clnt_dg.c,v 1.4 2000/07/14 08:40:41 fvdl Exp $ */
2
3 /*-
4 * SPDX-License-Identifier: BSD-3-Clause
5 *
6 * Copyright (c) 2009, Sun Microsystems, Inc.
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are met:
11 * - Redistributions of source code must retain the above copyright notice,
12 * this list of conditions and the following disclaimer.
13 * - Redistributions in binary form must reproduce the above copyright notice,
14 * this list of conditions and the following disclaimer in the documentation
15 * and/or other materials provided with the distribution.
16 * - Neither the name of Sun Microsystems, Inc. nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
24 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32 /*
33 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
34 */
35
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #ident "@(#)clnt_dg.c 1.23 94/04/22 SMI"
38 static char sccsid[] = "@(#)clnt_dg.c 1.19 89/03/16 Copyr 1988 Sun Micro";
39 #endif
40 #include <sys/cdefs.h>
41 /*
42 * Implements a connectionless client side RPC.
43 */
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/kernel.h>
48 #include <sys/lock.h>
49 #include <sys/malloc.h>
50 #include <sys/mbuf.h>
51 #include <sys/mutex.h>
52 #include <sys/pcpu.h>
53 #include <sys/proc.h>
54 #include <sys/socket.h>
55 #include <sys/socketvar.h>
56 #include <sys/time.h>
57 #include <sys/uio.h>
58
59 #include <net/vnet.h>
60
61 #include <rpc/rpc.h>
62 #include <rpc/rpc_com.h>
63
64
65 #ifdef _FREEFALL_CONFIG
66 /*
67 * Disable RPC exponential back-off for FreeBSD.org systems.
68 */
69 #define RPC_MAX_BACKOFF 1 /* second */
70 #else
71 #define RPC_MAX_BACKOFF 30 /* seconds */
72 #endif
73
74 static bool_t time_not_ok(struct timeval *);
75 static enum clnt_stat clnt_dg_call(CLIENT *, struct rpc_callextra *,
76 rpcproc_t, struct mbuf *, struct mbuf **, struct timeval);
77 static void clnt_dg_geterr(CLIENT *, struct rpc_err *);
78 static bool_t clnt_dg_freeres(CLIENT *, xdrproc_t, void *);
79 static void clnt_dg_abort(CLIENT *);
80 static bool_t clnt_dg_control(CLIENT *, u_int, void *);
81 static void clnt_dg_close(CLIENT *);
82 static void clnt_dg_destroy(CLIENT *);
83 static int clnt_dg_soupcall(struct socket *so, void *arg, int waitflag);
84
85 static const struct clnt_ops clnt_dg_ops = {
86 .cl_call = clnt_dg_call,
87 .cl_abort = clnt_dg_abort,
88 .cl_geterr = clnt_dg_geterr,
89 .cl_freeres = clnt_dg_freeres,
90 .cl_close = clnt_dg_close,
91 .cl_destroy = clnt_dg_destroy,
92 .cl_control = clnt_dg_control
93 };
94
95 static volatile uint32_t rpc_xid = 0;
96
97 /*
98 * A pending RPC request which awaits a reply. Requests which have
99 * received their reply will have cr_xid set to zero and cr_mrep to
100 * the mbuf chain of the reply.
101 */
102 struct cu_request {
103 TAILQ_ENTRY(cu_request) cr_link;
104 CLIENT *cr_client; /* owner */
105 uint32_t cr_xid; /* XID of request */
106 struct mbuf *cr_mrep; /* reply received by upcall */
107 int cr_error; /* any error from upcall */
108 char cr_verf[MAX_AUTH_BYTES]; /* reply verf */
109 };
110
111 TAILQ_HEAD(cu_request_list, cu_request);
112
113 #define MCALL_MSG_SIZE 24
114
115 /*
116 * This structure is pointed to by the socket buffer's sb_upcallarg
117 * member. It is separate from the client private data to facilitate
118 * multiple clients sharing the same socket. The cs_lock mutex is used
119 * to protect all fields of this structure, the socket's receive
120 * buffer SOCKBUF_LOCK is used to ensure that exactly one of these
121 * structures is installed on the socket.
122 */
123 struct cu_socket {
124 struct mtx cs_lock;
125 int cs_refs; /* Count of clients */
126 struct cu_request_list cs_pending; /* Requests awaiting replies */
127 int cs_upcallrefs; /* Refcnt of upcalls in prog.*/
128 };
129
130 static void clnt_dg_upcallsdone(struct socket *, struct cu_socket *);
131
132 /*
133 * Private data kept per client handle
134 */
135 struct cu_data {
136 int cu_threads; /* # threads in clnt_vc_call */
137 bool_t cu_closing; /* TRUE if we are closing */
138 bool_t cu_closed; /* TRUE if we are closed */
139 struct socket *cu_socket; /* connection socket */
140 bool_t cu_closeit; /* opened by library */
141 struct sockaddr_storage cu_raddr; /* remote address */
142 int cu_rlen;
143 struct timeval cu_wait; /* retransmit interval */
144 struct timeval cu_total; /* total time for the call */
145 struct rpc_err cu_error;
146 uint32_t cu_xid;
147 char cu_mcallc[MCALL_MSG_SIZE]; /* marshalled callmsg */
148 size_t cu_mcalllen;
149 size_t cu_sendsz; /* send size */
150 size_t cu_recvsz; /* recv size */
151 int cu_async;
152 int cu_connect; /* Use connect(). */
153 int cu_connected; /* Have done connect(). */
154 const char *cu_waitchan;
155 int cu_waitflag;
156 int cu_cwnd; /* congestion window */
157 int cu_sent; /* number of in-flight RPCs */
158 bool_t cu_cwnd_wait;
159 };
160
161 #define CWNDSCALE 256
162 #define MAXCWND (32 * CWNDSCALE)
163
164 /*
165 * Connection less client creation returns with client handle parameters.
166 * Default options are set, which the user can change using clnt_control().
167 * fd should be open and bound.
168 * NB: The rpch->cl_auth is initialized to null authentication.
169 * Caller may wish to set this something more useful.
170 *
171 * sendsz and recvsz are the maximum allowable packet sizes that can be
172 * sent and received. Normally they are the same, but they can be
173 * changed to improve the program efficiency and buffer allocation.
174 * If they are 0, use the transport default.
175 *
176 * If svcaddr is NULL, returns NULL.
177 */
178 CLIENT *
clnt_dg_create(struct socket * so,struct sockaddr * svcaddr,rpcprog_t program,rpcvers_t version,size_t sendsz,size_t recvsz)179 clnt_dg_create(
180 struct socket *so,
181 struct sockaddr *svcaddr, /* servers address */
182 rpcprog_t program, /* program number */
183 rpcvers_t version, /* version number */
184 size_t sendsz, /* buffer recv size */
185 size_t recvsz) /* buffer send size */
186 {
187 CLIENT *cl = NULL; /* client handle */
188 struct cu_data *cu = NULL; /* private data */
189 struct cu_socket *cs = NULL;
190 struct sockbuf *sb;
191 struct timeval now;
192 struct rpc_msg call_msg;
193 struct __rpc_sockinfo si;
194 XDR xdrs;
195 int error;
196 uint32_t newxid;
197
198 if (svcaddr == NULL) {
199 rpc_createerr.cf_stat = RPC_UNKNOWNADDR;
200 return (NULL);
201 }
202
203 if (!__rpc_socket2sockinfo(so, &si)) {
204 rpc_createerr.cf_stat = RPC_TLIERROR;
205 rpc_createerr.cf_error.re_errno = 0;
206 return (NULL);
207 }
208
209 /*
210 * Find the receive and the send size
211 */
212 sendsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsz);
213 recvsz = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsz);
214 if ((sendsz == 0) || (recvsz == 0)) {
215 rpc_createerr.cf_stat = RPC_TLIERROR; /* XXX */
216 rpc_createerr.cf_error.re_errno = 0;
217 return (NULL);
218 }
219
220 cl = mem_alloc(sizeof (CLIENT));
221
222 /*
223 * Should be multiple of 4 for XDR.
224 */
225 sendsz = rounddown(sendsz + 3, 4);
226 recvsz = rounddown(recvsz + 3, 4);
227 cu = mem_alloc(sizeof (*cu));
228 cu->cu_threads = 0;
229 cu->cu_closing = FALSE;
230 cu->cu_closed = FALSE;
231 (void) memcpy(&cu->cu_raddr, svcaddr, (size_t)svcaddr->sa_len);
232 cu->cu_rlen = svcaddr->sa_len;
233 /* Other values can also be set through clnt_control() */
234 cu->cu_wait.tv_sec = 3; /* heuristically chosen */
235 cu->cu_wait.tv_usec = 0;
236 cu->cu_total.tv_sec = -1;
237 cu->cu_total.tv_usec = -1;
238 cu->cu_sendsz = sendsz;
239 cu->cu_recvsz = recvsz;
240 cu->cu_async = FALSE;
241 cu->cu_connect = FALSE;
242 cu->cu_connected = FALSE;
243 cu->cu_waitchan = "rpcrecv";
244 cu->cu_waitflag = 0;
245 cu->cu_cwnd = MAXCWND / 2;
246 cu->cu_sent = 0;
247 cu->cu_cwnd_wait = FALSE;
248 (void) getmicrotime(&now);
249 /* Clip at 28bits so that it will not wrap around. */
250 newxid = __RPC_GETXID(&now) & 0xfffffff;
251 atomic_cmpset_32(&rpc_xid, 0, newxid);
252 call_msg.rm_xid = atomic_fetchadd_32(&rpc_xid, 1);
253 call_msg.rm_call.cb_prog = program;
254 call_msg.rm_call.cb_vers = version;
255 xdrmem_create(&xdrs, cu->cu_mcallc, MCALL_MSG_SIZE, XDR_ENCODE);
256 if (! xdr_callhdr(&xdrs, &call_msg)) {
257 rpc_createerr.cf_stat = RPC_CANTENCODEARGS; /* XXX */
258 rpc_createerr.cf_error.re_errno = 0;
259 goto err2;
260 }
261 cu->cu_mcalllen = XDR_GETPOS(&xdrs);
262
263 /*
264 * By default, closeit is always FALSE. It is users responsibility
265 * to do a close on it, else the user may use clnt_control
266 * to let clnt_destroy do it for him/her.
267 */
268 cu->cu_closeit = FALSE;
269 cu->cu_socket = so;
270 error = soreserve(so, (u_long)sendsz, (u_long)recvsz);
271 if (error != 0) {
272 rpc_createerr.cf_stat = RPC_FAILED;
273 rpc_createerr.cf_error.re_errno = error;
274 goto err2;
275 }
276
277 sb = &so->so_rcv;
278 SOCKBUF_LOCK(&so->so_rcv);
279 recheck_socket:
280 if (sb->sb_upcall) {
281 if (sb->sb_upcall != clnt_dg_soupcall) {
282 SOCKBUF_UNLOCK(&so->so_rcv);
283 printf("clnt_dg_create(): socket already has an incompatible upcall\n");
284 goto err2;
285 }
286 cs = (struct cu_socket *) sb->sb_upcallarg;
287 mtx_lock(&cs->cs_lock);
288 cs->cs_refs++;
289 mtx_unlock(&cs->cs_lock);
290 } else {
291 /*
292 * We are the first on this socket - allocate the
293 * structure and install it in the socket.
294 */
295 SOCKBUF_UNLOCK(&so->so_rcv);
296 cs = mem_alloc(sizeof(*cs));
297 SOCKBUF_LOCK(&so->so_rcv);
298 if (sb->sb_upcall) {
299 /*
300 * We have lost a race with some other client.
301 */
302 mem_free(cs, sizeof(*cs));
303 goto recheck_socket;
304 }
305 mtx_init(&cs->cs_lock, "cs->cs_lock", NULL, MTX_DEF);
306 cs->cs_refs = 1;
307 cs->cs_upcallrefs = 0;
308 TAILQ_INIT(&cs->cs_pending);
309 soupcall_set(so, SO_RCV, clnt_dg_soupcall, cs);
310 }
311 SOCKBUF_UNLOCK(&so->so_rcv);
312
313 cl->cl_refs = 1;
314 cl->cl_ops = &clnt_dg_ops;
315 cl->cl_private = (caddr_t)(void *)cu;
316 cl->cl_auth = authnone_create();
317 cl->cl_tp = NULL;
318 cl->cl_netid = NULL;
319 return (cl);
320 err2:
321 mem_free(cl, sizeof (CLIENT));
322 mem_free(cu, sizeof (*cu));
323
324 return (NULL);
325 }
326
327 static enum clnt_stat
clnt_dg_call(CLIENT * cl,struct rpc_callextra * ext,rpcproc_t proc,struct mbuf * args,struct mbuf ** resultsp,struct timeval utimeout)328 clnt_dg_call(
329 CLIENT *cl, /* client handle */
330 struct rpc_callextra *ext, /* call metadata */
331 rpcproc_t proc, /* procedure number */
332 struct mbuf *args, /* pointer to args */
333 struct mbuf **resultsp, /* pointer to results */
334 struct timeval utimeout) /* seconds to wait before giving up */
335 {
336 struct cu_data *cu = (struct cu_data *)cl->cl_private;
337 struct cu_socket *cs;
338 struct rpc_timers *rt;
339 AUTH *auth;
340 struct rpc_err *errp;
341 enum clnt_stat stat;
342 XDR xdrs;
343 struct rpc_msg reply_msg;
344 bool_t ok;
345 int retrans; /* number of re-transmits so far */
346 int nrefreshes = 2; /* number of times to refresh cred */
347 struct timeval *tvp;
348 int timeout;
349 int retransmit_time;
350 int next_sendtime, starttime, rtt, time_waited, tv = 0;
351 struct sockaddr *sa;
352 uint32_t xid = 0;
353 struct mbuf *mreq = NULL, *results;
354 struct cu_request *cr;
355 int error;
356
357 cs = cu->cu_socket->so_rcv.sb_upcallarg;
358 cr = malloc(sizeof(struct cu_request), M_RPC, M_WAITOK);
359
360 mtx_lock(&cs->cs_lock);
361
362 if (cu->cu_closing || cu->cu_closed) {
363 mtx_unlock(&cs->cs_lock);
364 free(cr, M_RPC);
365 return (RPC_CANTSEND);
366 }
367 cu->cu_threads++;
368
369 if (ext) {
370 auth = ext->rc_auth;
371 errp = &ext->rc_err;
372 } else {
373 auth = cl->cl_auth;
374 errp = &cu->cu_error;
375 }
376
377 cr->cr_client = cl;
378 cr->cr_mrep = NULL;
379 cr->cr_error = 0;
380
381 if (cu->cu_total.tv_usec == -1) {
382 tvp = &utimeout; /* use supplied timeout */
383 } else {
384 tvp = &cu->cu_total; /* use default timeout */
385 }
386 if (tvp->tv_sec || tvp->tv_usec)
387 timeout = tvtohz(tvp);
388 else
389 timeout = 0;
390
391 if (cu->cu_connect && !cu->cu_connected) {
392 mtx_unlock(&cs->cs_lock);
393 error = soconnect(cu->cu_socket,
394 (struct sockaddr *)&cu->cu_raddr, curthread);
395 mtx_lock(&cs->cs_lock);
396 if (error) {
397 errp->re_errno = error;
398 errp->re_status = stat = RPC_CANTSEND;
399 goto out;
400 }
401 cu->cu_connected = 1;
402 }
403 if (cu->cu_connected)
404 sa = NULL;
405 else
406 sa = (struct sockaddr *)&cu->cu_raddr;
407 time_waited = 0;
408 retrans = 0;
409 if (ext && ext->rc_timers) {
410 rt = ext->rc_timers;
411 if (!rt->rt_rtxcur)
412 rt->rt_rtxcur = tvtohz(&cu->cu_wait);
413 retransmit_time = next_sendtime = rt->rt_rtxcur;
414 } else {
415 rt = NULL;
416 retransmit_time = next_sendtime = tvtohz(&cu->cu_wait);
417 }
418
419 starttime = ticks;
420
421 call_again:
422 mtx_assert(&cs->cs_lock, MA_OWNED);
423
424 xid = atomic_fetchadd_32(&rpc_xid, 1);
425
426 send_again:
427 mtx_unlock(&cs->cs_lock);
428
429 mreq = m_gethdr(M_WAITOK, MT_DATA);
430 KASSERT(cu->cu_mcalllen <= MHLEN, ("RPC header too big"));
431 bcopy(cu->cu_mcallc, mreq->m_data, cu->cu_mcalllen);
432 mreq->m_len = cu->cu_mcalllen;
433
434 /*
435 * The XID is the first thing in the request.
436 */
437 *mtod(mreq, uint32_t *) = htonl(xid);
438
439 xdrmbuf_create(&xdrs, mreq, XDR_ENCODE);
440
441 if (cu->cu_async == TRUE && args == NULL)
442 goto get_reply;
443
444 if ((! XDR_PUTINT32(&xdrs, &proc)) ||
445 (! AUTH_MARSHALL(auth, xid, &xdrs,
446 m_copym(args, 0, M_COPYALL, M_WAITOK)))) {
447 errp->re_status = stat = RPC_CANTENCODEARGS;
448 mtx_lock(&cs->cs_lock);
449 goto out;
450 }
451 mreq->m_pkthdr.len = m_length(mreq, NULL);
452
453 cr->cr_xid = xid;
454 mtx_lock(&cs->cs_lock);
455
456 /*
457 * Try to get a place in the congestion window.
458 */
459 while (cu->cu_sent >= cu->cu_cwnd) {
460 cu->cu_cwnd_wait = TRUE;
461 error = msleep(&cu->cu_cwnd_wait, &cs->cs_lock,
462 cu->cu_waitflag, "rpccwnd", 0);
463 if (error) {
464 errp->re_errno = error;
465 if (error == EINTR || error == ERESTART)
466 errp->re_status = stat = RPC_INTR;
467 else
468 errp->re_status = stat = RPC_CANTSEND;
469 goto out;
470 }
471 }
472 cu->cu_sent += CWNDSCALE;
473
474 TAILQ_INSERT_TAIL(&cs->cs_pending, cr, cr_link);
475 mtx_unlock(&cs->cs_lock);
476
477 /*
478 * sosend consumes mreq.
479 */
480 error = sosend(cu->cu_socket, sa, NULL, mreq, NULL, 0, curthread);
481 mreq = NULL;
482
483 /*
484 * sub-optimal code appears here because we have
485 * some clock time to spare while the packets are in flight.
486 * (We assume that this is actually only executed once.)
487 */
488 reply_msg.acpted_rply.ar_verf.oa_flavor = AUTH_NULL;
489 reply_msg.acpted_rply.ar_verf.oa_base = cr->cr_verf;
490 reply_msg.acpted_rply.ar_verf.oa_length = 0;
491 reply_msg.acpted_rply.ar_results.where = NULL;
492 reply_msg.acpted_rply.ar_results.proc = (xdrproc_t)xdr_void;
493
494 mtx_lock(&cs->cs_lock);
495 if (error) {
496 TAILQ_REMOVE(&cs->cs_pending, cr, cr_link);
497 errp->re_errno = error;
498 errp->re_status = stat = RPC_CANTSEND;
499 cu->cu_sent -= CWNDSCALE;
500 if (cu->cu_cwnd_wait) {
501 cu->cu_cwnd_wait = FALSE;
502 wakeup(&cu->cu_cwnd_wait);
503 }
504 goto out;
505 }
506
507 /*
508 * Check to see if we got an upcall while waiting for the
509 * lock.
510 */
511 if (cr->cr_error) {
512 TAILQ_REMOVE(&cs->cs_pending, cr, cr_link);
513 errp->re_errno = cr->cr_error;
514 errp->re_status = stat = RPC_CANTRECV;
515 cu->cu_sent -= CWNDSCALE;
516 if (cu->cu_cwnd_wait) {
517 cu->cu_cwnd_wait = FALSE;
518 wakeup(&cu->cu_cwnd_wait);
519 }
520 goto out;
521 }
522 if (cr->cr_mrep) {
523 TAILQ_REMOVE(&cs->cs_pending, cr, cr_link);
524 cu->cu_sent -= CWNDSCALE;
525 if (cu->cu_cwnd_wait) {
526 cu->cu_cwnd_wait = FALSE;
527 wakeup(&cu->cu_cwnd_wait);
528 }
529 goto got_reply;
530 }
531
532 /*
533 * Hack to provide rpc-based message passing
534 */
535 if (timeout == 0) {
536 TAILQ_REMOVE(&cs->cs_pending, cr, cr_link);
537 errp->re_status = stat = RPC_TIMEDOUT;
538 cu->cu_sent -= CWNDSCALE;
539 if (cu->cu_cwnd_wait) {
540 cu->cu_cwnd_wait = FALSE;
541 wakeup(&cu->cu_cwnd_wait);
542 }
543 goto out;
544 }
545
546 get_reply:
547 for (;;) {
548 /* Decide how long to wait. */
549 if (next_sendtime < timeout)
550 tv = next_sendtime;
551 else
552 tv = timeout;
553 tv -= time_waited;
554
555 if (tv > 0) {
556 if (cu->cu_closing || cu->cu_closed) {
557 error = 0;
558 cr->cr_error = ESHUTDOWN;
559 } else {
560 error = msleep(cr, &cs->cs_lock,
561 cu->cu_waitflag, cu->cu_waitchan, tv);
562 }
563 } else {
564 error = EWOULDBLOCK;
565 }
566
567 TAILQ_REMOVE(&cs->cs_pending, cr, cr_link);
568 cu->cu_sent -= CWNDSCALE;
569 if (cu->cu_cwnd_wait) {
570 cu->cu_cwnd_wait = FALSE;
571 wakeup(&cu->cu_cwnd_wait);
572 }
573
574 if (!error) {
575 /*
576 * We were woken up by the upcall. If the
577 * upcall had a receive error, report that,
578 * otherwise we have a reply.
579 */
580 if (cr->cr_error) {
581 errp->re_errno = cr->cr_error;
582 errp->re_status = stat = RPC_CANTRECV;
583 goto out;
584 }
585
586 cu->cu_cwnd += (CWNDSCALE * CWNDSCALE
587 + cu->cu_cwnd / 2) / cu->cu_cwnd;
588 if (cu->cu_cwnd > MAXCWND)
589 cu->cu_cwnd = MAXCWND;
590
591 if (rt) {
592 /*
593 * Add one to the time since a tick
594 * count of N means that the actual
595 * time taken was somewhere between N
596 * and N+1.
597 */
598 rtt = ticks - starttime + 1;
599
600 /*
601 * Update our estimate of the round
602 * trip time using roughly the
603 * algorithm described in RFC
604 * 2988. Given an RTT sample R:
605 *
606 * RTTVAR = (1-beta) * RTTVAR + beta * |SRTT-R|
607 * SRTT = (1-alpha) * SRTT + alpha * R
608 *
609 * where alpha = 0.125 and beta = 0.25.
610 *
611 * The initial retransmit timeout is
612 * SRTT + 4*RTTVAR and doubles on each
613 * retransmision.
614 */
615 if (rt->rt_srtt == 0) {
616 rt->rt_srtt = rtt;
617 rt->rt_deviate = rtt / 2;
618 } else {
619 int32_t error = rtt - rt->rt_srtt;
620 rt->rt_srtt += error / 8;
621 error = abs(error) - rt->rt_deviate;
622 rt->rt_deviate += error / 4;
623 }
624 rt->rt_rtxcur = rt->rt_srtt + 4*rt->rt_deviate;
625 }
626
627 break;
628 }
629
630 /*
631 * The sleep returned an error so our request is still
632 * on the list. If we got EWOULDBLOCK, we may want to
633 * re-send the request.
634 */
635 if (error != EWOULDBLOCK) {
636 errp->re_errno = error;
637 if (error == EINTR || error == ERESTART)
638 errp->re_status = stat = RPC_INTR;
639 else
640 errp->re_status = stat = RPC_CANTRECV;
641 goto out;
642 }
643
644 time_waited = ticks - starttime;
645
646 /* Check for timeout. */
647 if (time_waited > timeout) {
648 errp->re_errno = EWOULDBLOCK;
649 errp->re_status = stat = RPC_TIMEDOUT;
650 goto out;
651 }
652
653 /* Retransmit if necessary. */
654 if (time_waited >= next_sendtime) {
655 cu->cu_cwnd /= 2;
656 if (cu->cu_cwnd < CWNDSCALE)
657 cu->cu_cwnd = CWNDSCALE;
658 if (ext && ext->rc_feedback) {
659 mtx_unlock(&cs->cs_lock);
660 if (retrans == 0)
661 ext->rc_feedback(FEEDBACK_REXMIT1,
662 proc, ext->rc_feedback_arg);
663 else
664 ext->rc_feedback(FEEDBACK_REXMIT2,
665 proc, ext->rc_feedback_arg);
666 mtx_lock(&cs->cs_lock);
667 }
668 if (cu->cu_closing || cu->cu_closed) {
669 errp->re_errno = ESHUTDOWN;
670 errp->re_status = stat = RPC_CANTRECV;
671 goto out;
672 }
673 retrans++;
674 /* update retransmit_time */
675 if (retransmit_time < RPC_MAX_BACKOFF * hz)
676 retransmit_time = 2 * retransmit_time;
677 next_sendtime += retransmit_time;
678 goto send_again;
679 }
680 cu->cu_sent += CWNDSCALE;
681 TAILQ_INSERT_TAIL(&cs->cs_pending, cr, cr_link);
682 }
683
684 got_reply:
685 /*
686 * Now decode and validate the response. We need to drop the
687 * lock since xdr_replymsg may end up sleeping in malloc.
688 */
689 mtx_unlock(&cs->cs_lock);
690
691 if (ext && ext->rc_feedback)
692 ext->rc_feedback(FEEDBACK_OK, proc, ext->rc_feedback_arg);
693
694 xdrmbuf_create(&xdrs, cr->cr_mrep, XDR_DECODE);
695 ok = xdr_replymsg(&xdrs, &reply_msg);
696 cr->cr_mrep = NULL;
697
698 if (ok) {
699 if ((reply_msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
700 (reply_msg.acpted_rply.ar_stat == SUCCESS))
701 errp->re_status = stat = RPC_SUCCESS;
702 else
703 stat = _seterr_reply(&reply_msg, &(cu->cu_error));
704
705 if (errp->re_status == RPC_SUCCESS) {
706 results = xdrmbuf_getall(&xdrs);
707 if (! AUTH_VALIDATE(auth, xid,
708 &reply_msg.acpted_rply.ar_verf,
709 &results)) {
710 errp->re_status = stat = RPC_AUTHERROR;
711 errp->re_why = AUTH_INVALIDRESP;
712 if (retrans &&
713 auth->ah_cred.oa_flavor == RPCSEC_GSS) {
714 /*
715 * If we retransmitted, its
716 * possible that we will
717 * receive a reply for one of
718 * the earlier transmissions
719 * (which will use an older
720 * RPCSEC_GSS sequence
721 * number). In this case, just
722 * go back and listen for a
723 * new reply. We could keep a
724 * record of all the seq
725 * numbers we have transmitted
726 * so far so that we could
727 * accept a reply for any of
728 * them here.
729 */
730 XDR_DESTROY(&xdrs);
731 mtx_lock(&cs->cs_lock);
732 cu->cu_sent += CWNDSCALE;
733 TAILQ_INSERT_TAIL(&cs->cs_pending,
734 cr, cr_link);
735 cr->cr_mrep = NULL;
736 goto get_reply;
737 }
738 } else {
739 *resultsp = results;
740 }
741 } /* end successful completion */
742 /*
743 * If unsuccessful AND error is an authentication error
744 * then refresh credentials and try again, else break
745 */
746 else if (stat == RPC_AUTHERROR)
747 /* maybe our credentials need to be refreshed ... */
748 if (nrefreshes > 0 &&
749 AUTH_REFRESH(auth, &reply_msg)) {
750 nrefreshes--;
751 XDR_DESTROY(&xdrs);
752 mtx_lock(&cs->cs_lock);
753 goto call_again;
754 }
755 /* end of unsuccessful completion */
756 } /* end of valid reply message */
757 else {
758 errp->re_status = stat = RPC_CANTDECODERES;
759
760 }
761 XDR_DESTROY(&xdrs);
762 mtx_lock(&cs->cs_lock);
763 out:
764 mtx_assert(&cs->cs_lock, MA_OWNED);
765
766 if (mreq)
767 m_freem(mreq);
768 if (cr->cr_mrep)
769 m_freem(cr->cr_mrep);
770
771 cu->cu_threads--;
772 if (cu->cu_closing)
773 wakeup(cu);
774
775 mtx_unlock(&cs->cs_lock);
776
777 if (auth && stat != RPC_SUCCESS)
778 AUTH_VALIDATE(auth, xid, NULL, NULL);
779
780 free(cr, M_RPC);
781
782 return (stat);
783 }
784
785 static void
clnt_dg_geterr(CLIENT * cl,struct rpc_err * errp)786 clnt_dg_geterr(CLIENT *cl, struct rpc_err *errp)
787 {
788 struct cu_data *cu = (struct cu_data *)cl->cl_private;
789
790 *errp = cu->cu_error;
791 }
792
793 static bool_t
clnt_dg_freeres(CLIENT * cl,xdrproc_t xdr_res,void * res_ptr)794 clnt_dg_freeres(CLIENT *cl, xdrproc_t xdr_res, void *res_ptr)
795 {
796 XDR xdrs;
797 bool_t dummy;
798
799 xdrs.x_op = XDR_FREE;
800 dummy = (*xdr_res)(&xdrs, res_ptr);
801
802 return (dummy);
803 }
804
805 /*ARGSUSED*/
806 static void
clnt_dg_abort(CLIENT * h)807 clnt_dg_abort(CLIENT *h)
808 {
809 }
810
811 static bool_t
clnt_dg_control(CLIENT * cl,u_int request,void * info)812 clnt_dg_control(CLIENT *cl, u_int request, void *info)
813 {
814 struct cu_data *cu = (struct cu_data *)cl->cl_private;
815 struct cu_socket *cs;
816 struct sockaddr *addr;
817
818 cs = cu->cu_socket->so_rcv.sb_upcallarg;
819 mtx_lock(&cs->cs_lock);
820
821 switch (request) {
822 case CLSET_FD_CLOSE:
823 cu->cu_closeit = TRUE;
824 mtx_unlock(&cs->cs_lock);
825 return (TRUE);
826 case CLSET_FD_NCLOSE:
827 cu->cu_closeit = FALSE;
828 mtx_unlock(&cs->cs_lock);
829 return (TRUE);
830 }
831
832 /* for other requests which use info */
833 if (info == NULL) {
834 mtx_unlock(&cs->cs_lock);
835 return (FALSE);
836 }
837 switch (request) {
838 case CLSET_TIMEOUT:
839 if (time_not_ok((struct timeval *)info)) {
840 mtx_unlock(&cs->cs_lock);
841 return (FALSE);
842 }
843 cu->cu_total = *(struct timeval *)info;
844 break;
845 case CLGET_TIMEOUT:
846 *(struct timeval *)info = cu->cu_total;
847 break;
848 case CLSET_RETRY_TIMEOUT:
849 if (time_not_ok((struct timeval *)info)) {
850 mtx_unlock(&cs->cs_lock);
851 return (FALSE);
852 }
853 cu->cu_wait = *(struct timeval *)info;
854 break;
855 case CLGET_RETRY_TIMEOUT:
856 *(struct timeval *)info = cu->cu_wait;
857 break;
858 case CLGET_SVC_ADDR:
859 /*
860 * Slightly different semantics to userland - we use
861 * sockaddr instead of netbuf.
862 */
863 memcpy(info, &cu->cu_raddr, cu->cu_raddr.ss_len);
864 break;
865 case CLSET_SVC_ADDR: /* set to new address */
866 addr = (struct sockaddr *)info;
867 (void) memcpy(&cu->cu_raddr, addr, addr->sa_len);
868 break;
869 case CLGET_XID:
870 *(uint32_t *)info = atomic_load_32(&rpc_xid);
871 break;
872
873 case CLSET_XID:
874 /* This will set the xid of the NEXT call */
875 /* decrement by 1 as clnt_dg_call() increments once */
876 atomic_store_32(&rpc_xid, *(uint32_t *)info - 1);
877 break;
878
879 case CLGET_VERS:
880 /*
881 * This RELIES on the information that, in the call body,
882 * the version number field is the fifth field from the
883 * beginning of the RPC header. MUST be changed if the
884 * call_struct is changed
885 */
886 *(uint32_t *)info =
887 ntohl(*(uint32_t *)(void *)(cu->cu_mcallc +
888 4 * BYTES_PER_XDR_UNIT));
889 break;
890
891 case CLSET_VERS:
892 *(uint32_t *)(void *)(cu->cu_mcallc + 4 * BYTES_PER_XDR_UNIT)
893 = htonl(*(uint32_t *)info);
894 break;
895
896 case CLGET_PROG:
897 /*
898 * This RELIES on the information that, in the call body,
899 * the program number field is the fourth field from the
900 * beginning of the RPC header. MUST be changed if the
901 * call_struct is changed
902 */
903 *(uint32_t *)info =
904 ntohl(*(uint32_t *)(void *)(cu->cu_mcallc +
905 3 * BYTES_PER_XDR_UNIT));
906 break;
907
908 case CLSET_PROG:
909 *(uint32_t *)(void *)(cu->cu_mcallc + 3 * BYTES_PER_XDR_UNIT)
910 = htonl(*(uint32_t *)info);
911 break;
912 case CLSET_ASYNC:
913 cu->cu_async = *(int *)info;
914 break;
915 case CLSET_CONNECT:
916 cu->cu_connect = *(int *)info;
917 break;
918 case CLSET_WAITCHAN:
919 cu->cu_waitchan = (const char *)info;
920 break;
921 case CLGET_WAITCHAN:
922 *(const char **) info = cu->cu_waitchan;
923 break;
924 case CLSET_INTERRUPTIBLE:
925 if (*(int *) info)
926 cu->cu_waitflag = PCATCH;
927 else
928 cu->cu_waitflag = 0;
929 break;
930 case CLGET_INTERRUPTIBLE:
931 if (cu->cu_waitflag)
932 *(int *) info = TRUE;
933 else
934 *(int *) info = FALSE;
935 break;
936 default:
937 mtx_unlock(&cs->cs_lock);
938 return (FALSE);
939 }
940 mtx_unlock(&cs->cs_lock);
941 return (TRUE);
942 }
943
944 static void
clnt_dg_close(CLIENT * cl)945 clnt_dg_close(CLIENT *cl)
946 {
947 struct cu_data *cu = (struct cu_data *)cl->cl_private;
948 struct cu_socket *cs;
949 struct cu_request *cr;
950
951 cs = cu->cu_socket->so_rcv.sb_upcallarg;
952 mtx_lock(&cs->cs_lock);
953
954 if (cu->cu_closed) {
955 mtx_unlock(&cs->cs_lock);
956 return;
957 }
958
959 if (cu->cu_closing) {
960 while (cu->cu_closing)
961 msleep(cu, &cs->cs_lock, 0, "rpcclose", 0);
962 KASSERT(cu->cu_closed, ("client should be closed"));
963 mtx_unlock(&cs->cs_lock);
964 return;
965 }
966
967 /*
968 * Abort any pending requests and wait until everyone
969 * has finished with clnt_vc_call.
970 */
971 cu->cu_closing = TRUE;
972 TAILQ_FOREACH(cr, &cs->cs_pending, cr_link) {
973 if (cr->cr_client == cl) {
974 cr->cr_xid = 0;
975 cr->cr_error = ESHUTDOWN;
976 wakeup(cr);
977 }
978 }
979
980 while (cu->cu_threads)
981 msleep(cu, &cs->cs_lock, 0, "rpcclose", 0);
982
983 cu->cu_closing = FALSE;
984 cu->cu_closed = TRUE;
985
986 mtx_unlock(&cs->cs_lock);
987 wakeup(cu);
988 }
989
990 static void
clnt_dg_destroy(CLIENT * cl)991 clnt_dg_destroy(CLIENT *cl)
992 {
993 struct cu_data *cu = (struct cu_data *)cl->cl_private;
994 struct cu_socket *cs;
995 struct socket *so = NULL;
996 bool_t lastsocketref;
997
998 cs = cu->cu_socket->so_rcv.sb_upcallarg;
999 clnt_dg_close(cl);
1000
1001 SOCKBUF_LOCK(&cu->cu_socket->so_rcv);
1002 mtx_lock(&cs->cs_lock);
1003
1004 cs->cs_refs--;
1005 if (cs->cs_refs == 0) {
1006 mtx_unlock(&cs->cs_lock);
1007 soupcall_clear(cu->cu_socket, SO_RCV);
1008 clnt_dg_upcallsdone(cu->cu_socket, cs);
1009 SOCKBUF_UNLOCK(&cu->cu_socket->so_rcv);
1010 mtx_destroy(&cs->cs_lock);
1011 mem_free(cs, sizeof(*cs));
1012 lastsocketref = TRUE;
1013 } else {
1014 mtx_unlock(&cs->cs_lock);
1015 SOCKBUF_UNLOCK(&cu->cu_socket->so_rcv);
1016 lastsocketref = FALSE;
1017 }
1018
1019 if (cu->cu_closeit && lastsocketref) {
1020 so = cu->cu_socket;
1021 cu->cu_socket = NULL;
1022 }
1023
1024 if (so)
1025 soclose(so);
1026
1027 if (cl->cl_netid && cl->cl_netid[0])
1028 mem_free(cl->cl_netid, strlen(cl->cl_netid) +1);
1029 if (cl->cl_tp && cl->cl_tp[0])
1030 mem_free(cl->cl_tp, strlen(cl->cl_tp) +1);
1031 mem_free(cu, sizeof (*cu));
1032 mem_free(cl, sizeof (CLIENT));
1033 }
1034
1035 /*
1036 * Make sure that the time is not garbage. -1 value is allowed.
1037 */
1038 static bool_t
time_not_ok(struct timeval * t)1039 time_not_ok(struct timeval *t)
1040 {
1041 return (t->tv_sec < -1 || t->tv_sec > 100000000 ||
1042 t->tv_usec < -1 || t->tv_usec > 1000000);
1043 }
1044
1045 int
clnt_dg_soupcall(struct socket * so,void * arg,int waitflag)1046 clnt_dg_soupcall(struct socket *so, void *arg, int waitflag)
1047 {
1048 struct cu_socket *cs = (struct cu_socket *) arg;
1049 struct uio uio;
1050 struct mbuf *m;
1051 struct mbuf *control;
1052 struct cu_request *cr;
1053 int error, rcvflag, foundreq;
1054 uint32_t xid;
1055
1056 cs->cs_upcallrefs++;
1057 uio.uio_resid = 1000000000;
1058 uio.uio_td = curthread;
1059 do {
1060 SOCKBUF_UNLOCK(&so->so_rcv);
1061 m = NULL;
1062 control = NULL;
1063 rcvflag = MSG_DONTWAIT;
1064 error = soreceive(so, NULL, &uio, &m, &control, &rcvflag);
1065 if (control)
1066 m_freem(control);
1067 SOCKBUF_LOCK(&so->so_rcv);
1068
1069 if (error == EWOULDBLOCK)
1070 break;
1071
1072 /*
1073 * If there was an error, wake up all pending
1074 * requests.
1075 */
1076 if (error) {
1077 mtx_lock(&cs->cs_lock);
1078 TAILQ_FOREACH(cr, &cs->cs_pending, cr_link) {
1079 cr->cr_xid = 0;
1080 cr->cr_error = error;
1081 wakeup(cr);
1082 }
1083 mtx_unlock(&cs->cs_lock);
1084 break;
1085 }
1086
1087 /*
1088 * The XID is in the first uint32_t of the reply.
1089 */
1090 if (m->m_len < sizeof(xid) && m_length(m, NULL) < sizeof(xid)) {
1091 /*
1092 * Should never happen.
1093 */
1094 m_freem(m);
1095 continue;
1096 }
1097
1098 m_copydata(m, 0, sizeof(xid), (char *)&xid);
1099 xid = ntohl(xid);
1100
1101 /*
1102 * Attempt to match this reply with a pending request.
1103 */
1104 mtx_lock(&cs->cs_lock);
1105 foundreq = 0;
1106 TAILQ_FOREACH(cr, &cs->cs_pending, cr_link) {
1107 if (cr->cr_xid == xid) {
1108 /*
1109 * This one matches. We leave the
1110 * reply mbuf in cr->cr_mrep. Set the
1111 * XID to zero so that we will ignore
1112 * any duplicated replies that arrive
1113 * before clnt_dg_call removes it from
1114 * the queue.
1115 */
1116 cr->cr_xid = 0;
1117 cr->cr_mrep = m;
1118 cr->cr_error = 0;
1119 foundreq = 1;
1120 wakeup(cr);
1121 break;
1122 }
1123 }
1124 mtx_unlock(&cs->cs_lock);
1125
1126 /*
1127 * If we didn't find the matching request, just drop
1128 * it - its probably a repeated reply.
1129 */
1130 if (!foundreq)
1131 m_freem(m);
1132 } while (m);
1133 cs->cs_upcallrefs--;
1134 if (cs->cs_upcallrefs < 0)
1135 panic("rpcdg upcall refcnt");
1136 if (cs->cs_upcallrefs == 0)
1137 wakeup(&cs->cs_upcallrefs);
1138 return (SU_OK);
1139 }
1140
1141 /*
1142 * Wait for all upcalls in progress to complete.
1143 */
1144 static void
clnt_dg_upcallsdone(struct socket * so,struct cu_socket * cs)1145 clnt_dg_upcallsdone(struct socket *so, struct cu_socket *cs)
1146 {
1147
1148 SOCKBUF_LOCK_ASSERT(&so->so_rcv);
1149
1150 while (cs->cs_upcallrefs > 0)
1151 (void) msleep(&cs->cs_upcallrefs, SOCKBUF_MTX(&so->so_rcv), 0,
1152 "rpcdgup", 0);
1153 }
1154