1 /* $NetBSD: svc_dg.c,v 1.4 2000/07/06 03:10:35 christos Exp $ */
4 * Copyright (c) 2009, Sun Microsystems, Inc.
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.
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.
32 * Copyright (c) 1986-1991 by Sun Microsystems Inc.
35 #if defined(LIBC_SCCS) && !defined(lint)
36 #ident "@(#)svc_dg.c 1.17 94/04/24 SMI"
38 #include <sys/cdefs.h>
39 __FBSDID("$FreeBSD$");
42 * svc_dg.c, Server side for connectionless RPC.
44 * Does some caching in the hopes of achieving execute-at-most-once semantics.
47 #include "namespace.h"
48 #include "reentrant.h"
49 #include <sys/types.h>
50 #include <sys/socket.h>
52 #include <rpc/svc_dg.h>
59 #ifdef RPC_CACHE_DEBUG
60 #include <netconfig.h>
64 #include "un-namespace.h"
69 #define su_data(xprt) ((struct svc_dg_data *)(xprt->xp_p2))
70 #define rpc_buffer(xprt) ((xprt)->xp_p1)
73 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
76 static void svc_dg_ops(SVCXPRT *);
77 static enum xprt_stat svc_dg_stat(SVCXPRT *);
78 static bool_t svc_dg_recv(SVCXPRT *, struct rpc_msg *);
79 static bool_t svc_dg_reply(SVCXPRT *, struct rpc_msg *);
80 static bool_t svc_dg_getargs(SVCXPRT *, xdrproc_t, void *);
81 static bool_t svc_dg_freeargs(SVCXPRT *, xdrproc_t, void *);
82 static void svc_dg_destroy(SVCXPRT *);
83 static bool_t svc_dg_control(SVCXPRT *, const u_int, void *);
84 static int cache_get(SVCXPRT *, struct rpc_msg *, char **, size_t *);
85 static void cache_set(SVCXPRT *, size_t);
86 int svc_dg_enablecache(SVCXPRT *, u_int);
90 * xprt = svc_dg_create(sock, sendsize, recvsize);
91 * Does other connectionless specific initializations.
92 * Once *xprt is initialized, it is registered.
93 * see (svc.h, xprt_register). If recvsize or sendsize are 0 suitable
94 * system defaults are chosen.
95 * The routines returns NULL if a problem occurred.
97 static const char svc_dg_str[] = "svc_dg_create: %s";
98 static const char svc_dg_err1[] = "could not get transport information";
99 static const char svc_dg_err2[] = "transport does not support data transfer";
100 static const char svc_dg_err3[] = "getsockname failed";
101 static const char svc_dg_err4[] = "cannot set IP_RECVDSTADDR";
102 static const char __no_mem_str[] = "out of memory";
105 svc_dg_create(int fd, u_int sendsize, u_int recvsize)
108 struct svc_dg_data *su = NULL;
109 struct __rpc_sockinfo si;
110 struct sockaddr_storage ss;
113 if (!__rpc_fd2sockinfo(fd, &si)) {
114 warnx(svc_dg_str, svc_dg_err1);
118 * Find the receive and the send size
120 sendsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsize);
121 recvsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsize);
122 if ((sendsize == 0) || (recvsize == 0)) {
123 warnx(svc_dg_str, svc_dg_err2);
127 xprt = svc_xprt_alloc();
131 su = mem_alloc(sizeof (*su));
134 su->su_iosz = ((MAX(sendsize, recvsize) + 3) / 4) * 4;
135 if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL)
137 xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
142 xprt->xp_verf.oa_base = su->su_verfbody;
144 xprt->xp_rtaddr.maxlen = sizeof (struct sockaddr_storage);
147 if (_getsockname(fd, (struct sockaddr *)(void *)&ss, &slen) < 0) {
148 warnx(svc_dg_str, svc_dg_err3);
149 goto freedata_nowarn;
151 xprt->xp_ltaddr.buf = mem_alloc(sizeof (struct sockaddr_storage));
152 xprt->xp_ltaddr.maxlen = sizeof (struct sockaddr_storage);
153 xprt->xp_ltaddr.len = slen;
154 memcpy(xprt->xp_ltaddr.buf, &ss, slen);
156 if (ss.ss_family == AF_INET) {
157 struct sockaddr_in *sin;
158 static const int true_value = 1;
160 sin = (struct sockaddr_in *)(void *)&ss;
161 if (sin->sin_addr.s_addr == INADDR_ANY) {
162 su->su_srcaddr.buf = mem_alloc(sizeof (ss));
163 su->su_srcaddr.maxlen = sizeof (ss);
165 if (_setsockopt(fd, IPPROTO_IP, IP_RECVDSTADDR,
166 &true_value, sizeof(true_value))) {
167 warnx(svc_dg_str, svc_dg_err4);
168 goto freedata_nowarn;
176 (void) warnx(svc_dg_str, __no_mem_str);
180 (void) mem_free(su, sizeof (*su));
187 static enum xprt_stat
188 svc_dg_stat(SVCXPRT *xprt)
194 svc_dg_recvfrom(int fd, char *buf, int buflen,
195 struct sockaddr *raddr, socklen_t *raddrlen,
196 struct sockaddr *laddr, socklen_t *laddrlen)
199 struct iovec msg_iov[1];
200 struct sockaddr_in *lin = (struct sockaddr_in *)laddr;
202 bool_t have_lin = FALSE;
203 char tmp[CMSG_LEN(sizeof(*lin))];
204 struct cmsghdr *cmsg;
206 memset((char *)&msg, 0, sizeof(msg));
207 msg_iov[0].iov_base = buf;
208 msg_iov[0].iov_len = buflen;
209 msg.msg_iov = msg_iov;
211 msg.msg_namelen = *raddrlen;
212 msg.msg_name = (char *)raddr;
214 msg.msg_control = (caddr_t)tmp;
215 msg.msg_controllen = CMSG_LEN(sizeof(*lin));
217 rlen = _recvmsg(fd, &msg, 0);
219 *raddrlen = msg.msg_namelen;
221 if (rlen == -1 || laddr == NULL ||
222 msg.msg_controllen < sizeof(struct cmsghdr) ||
223 msg.msg_flags & MSG_CTRUNC)
226 for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
227 cmsg = CMSG_NXTHDR(&msg, cmsg)) {
228 if (cmsg->cmsg_level == IPPROTO_IP &&
229 cmsg->cmsg_type == IP_RECVDSTADDR) {
231 memcpy(&lin->sin_addr,
232 (struct in_addr *)CMSG_DATA(cmsg),
233 sizeof(struct in_addr));
238 lin->sin_family = AF_INET;
240 *laddrlen = sizeof(struct sockaddr_in);
243 lin->sin_addr.s_addr = INADDR_ANY;
249 svc_dg_recv(SVCXPRT *xprt, struct rpc_msg *msg)
251 struct svc_dg_data *su = su_data(xprt);
252 XDR *xdrs = &(su->su_xdrs);
254 struct sockaddr_storage ss;
260 alen = sizeof (struct sockaddr_storage);
261 rlen = svc_dg_recvfrom(xprt->xp_fd, rpc_buffer(xprt), su->su_iosz,
262 (struct sockaddr *)(void *)&ss, &alen,
263 (struct sockaddr *)su->su_srcaddr.buf, &su->su_srcaddr.len);
264 if (rlen == -1 && errno == EINTR)
266 if (rlen == -1 || (rlen < (ssize_t)(4 * sizeof (u_int32_t))))
268 if (xprt->xp_rtaddr.len < alen) {
269 if (xprt->xp_rtaddr.len != 0)
270 mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.len);
271 xprt->xp_rtaddr.buf = mem_alloc(alen);
272 xprt->xp_rtaddr.len = alen;
274 memcpy(xprt->xp_rtaddr.buf, &ss, alen);
276 if (ss.ss_family == AF_INET) {
277 xprt->xp_raddr = *(struct sockaddr_in *)xprt->xp_rtaddr.buf;
278 xprt->xp_addrlen = sizeof (struct sockaddr_in);
281 xdrs->x_op = XDR_DECODE;
283 if (! xdr_callmsg(xdrs, msg)) {
286 su->su_xid = msg->rm_xid;
287 if (su->su_cache != NULL) {
288 if (cache_get(xprt, msg, &reply, &replylen)) {
289 (void)_sendto(xprt->xp_fd, reply, replylen, 0,
290 (struct sockaddr *)(void *)&ss, alen);
298 svc_dg_sendto(int fd, char *buf, int buflen,
299 const struct sockaddr *raddr, socklen_t raddrlen,
300 const struct sockaddr *laddr, socklen_t laddrlen)
303 struct iovec msg_iov[1];
304 struct sockaddr_in *laddr_in = (struct sockaddr_in *)laddr;
305 struct in_addr *lin = &laddr_in->sin_addr;
306 char tmp[CMSG_SPACE(sizeof(*lin))];
307 struct cmsghdr *cmsg;
309 memset((char *)&msg, 0, sizeof(msg));
310 msg_iov[0].iov_base = buf;
311 msg_iov[0].iov_len = buflen;
312 msg.msg_iov = msg_iov;
314 msg.msg_namelen = raddrlen;
315 msg.msg_name = (char *)raddr;
317 if (laddr != NULL && laddr->sa_family == AF_INET &&
318 lin->s_addr != INADDR_ANY) {
319 msg.msg_control = (caddr_t)tmp;
320 msg.msg_controllen = CMSG_LEN(sizeof(*lin));
321 cmsg = CMSG_FIRSTHDR(&msg);
322 cmsg->cmsg_len = CMSG_LEN(sizeof(*lin));
323 cmsg->cmsg_level = IPPROTO_IP;
324 cmsg->cmsg_type = IP_SENDSRCADDR;
325 memcpy(CMSG_DATA(cmsg), lin, sizeof(*lin));
328 return _sendmsg(fd, &msg, 0);
332 svc_dg_reply(SVCXPRT *xprt, struct rpc_msg *msg)
334 struct svc_dg_data *su = su_data(xprt);
335 XDR *xdrs = &(su->su_xdrs);
341 xdrs->x_op = XDR_ENCODE;
343 msg->rm_xid = su->su_xid;
344 if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
345 msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
346 xdr_proc = msg->acpted_rply.ar_results.proc;
347 xdr_where = msg->acpted_rply.ar_results.where;
348 msg->acpted_rply.ar_results.proc = (xdrproc_t) xdr_void;
349 msg->acpted_rply.ar_results.where = NULL;
351 if (!xdr_replymsg(xdrs, msg) ||
352 !SVCAUTH_WRAP(&SVC_AUTH(xprt), xdrs, xdr_proc, xdr_where))
355 stat = xdr_replymsg(xdrs, msg);
358 slen = XDR_GETPOS(xdrs);
359 if (svc_dg_sendto(xprt->xp_fd, rpc_buffer(xprt), slen,
360 (struct sockaddr *)xprt->xp_rtaddr.buf,
361 (socklen_t)xprt->xp_rtaddr.len,
362 (struct sockaddr *)su->su_srcaddr.buf,
363 (socklen_t)su->su_srcaddr.len) == (ssize_t) slen) {
366 cache_set(xprt, slen);
373 svc_dg_getargs(SVCXPRT *xprt, xdrproc_t xdr_args, void *args_ptr)
375 struct svc_dg_data *su;
377 assert(xprt != NULL);
379 return (SVCAUTH_UNWRAP(&SVC_AUTH(xprt),
380 &su->su_xdrs, xdr_args, args_ptr));
384 svc_dg_freeargs(SVCXPRT *xprt, xdrproc_t xdr_args, void *args_ptr)
386 XDR *xdrs = &(su_data(xprt)->su_xdrs);
388 xdrs->x_op = XDR_FREE;
389 return (*xdr_args)(xdrs, args_ptr);
393 svc_dg_destroy(SVCXPRT *xprt)
395 struct svc_dg_data *su = su_data(xprt);
397 xprt_unregister(xprt);
398 if (xprt->xp_fd != -1)
399 (void)_close(xprt->xp_fd);
400 XDR_DESTROY(&(su->su_xdrs));
401 (void) mem_free(rpc_buffer(xprt), su->su_iosz);
402 if (su->su_srcaddr.buf)
403 (void) mem_free(su->su_srcaddr.buf, su->su_srcaddr.maxlen);
404 (void) mem_free(su, sizeof (*su));
405 if (xprt->xp_rtaddr.buf)
406 (void) mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.maxlen);
407 if (xprt->xp_ltaddr.buf)
408 (void) mem_free(xprt->xp_ltaddr.buf, xprt->xp_ltaddr.maxlen);
415 svc_dg_control(SVCXPRT *xprt, const u_int rq, void *in)
421 svc_dg_ops(SVCXPRT *xprt)
423 static struct xp_ops ops;
424 static struct xp_ops2 ops2;
426 /* VARIABLES PROTECTED BY ops_lock: ops */
428 mutex_lock(&ops_lock);
429 if (ops.xp_recv == NULL) {
430 ops.xp_recv = svc_dg_recv;
431 ops.xp_stat = svc_dg_stat;
432 ops.xp_getargs = svc_dg_getargs;
433 ops.xp_reply = svc_dg_reply;
434 ops.xp_freeargs = svc_dg_freeargs;
435 ops.xp_destroy = svc_dg_destroy;
436 ops2.xp_control = svc_dg_control;
439 xprt->xp_ops2 = &ops2;
440 mutex_unlock(&ops_lock);
443 /* The CACHING COMPONENT */
446 * Could have been a separate file, but some part of it depends upon the
447 * private structure of the client handle.
449 * Fifo cache for cl server
450 * Copies pointers to reply buffers into fifo cache
451 * Buffers are sent again if retransmissions are detected.
454 #define SPARSENESS 4 /* 75% sparse */
456 #define ALLOC(type, size) \
457 (type *) mem_alloc((sizeof (type) * (size)))
459 #define MEMZERO(addr, type, size) \
460 (void) memset((void *) (addr), 0, sizeof (type) * (int) (size))
462 #define FREE(addr, type, size) \
463 mem_free((addr), (sizeof (type) * (size)))
466 * An entry in the cache
468 typedef struct cache_node *cache_ptr;
471 * Index into cache is xid, proc, vers, prog and address
474 rpcproc_t cache_proc;
475 rpcvers_t cache_vers;
476 rpcprog_t cache_prog;
477 struct netbuf cache_addr;
479 * The cached reply and length
482 size_t cache_replylen;
484 * Next node on the list, if there is a collision
486 cache_ptr cache_next;
493 u_int uc_size; /* size of cache */
494 cache_ptr *uc_entries; /* hash table of entries in cache */
495 cache_ptr *uc_fifo; /* fifo list of entries in cache */
496 u_int uc_nextvictim; /* points to next victim in fifo list */
497 rpcprog_t uc_prog; /* saved program number */
498 rpcvers_t uc_vers; /* saved version number */
499 rpcproc_t uc_proc; /* saved procedure number */
504 * the hashing function
506 #define CACHE_LOC(transp, xid) \
507 (xid % (SPARSENESS * ((struct cl_cache *) \
508 su_data(transp)->su_cache)->uc_size))
511 * Enable use of the cache. Returns 1 on success, 0 on failure.
512 * Note: there is no disable.
514 static const char cache_enable_str[] = "svc_enablecache: %s %s";
515 static const char alloc_err[] = "could not allocate cache ";
516 static const char enable_err[] = "cache already enabled";
519 svc_dg_enablecache(SVCXPRT *transp, u_int size)
521 struct svc_dg_data *su = su_data(transp);
524 mutex_lock(&dupreq_lock);
525 if (su->su_cache != NULL) {
526 (void) warnx(cache_enable_str, enable_err, " ");
527 mutex_unlock(&dupreq_lock);
530 uc = ALLOC(struct cl_cache, 1);
532 warnx(cache_enable_str, alloc_err, " ");
533 mutex_unlock(&dupreq_lock);
537 uc->uc_nextvictim = 0;
538 uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
539 if (uc->uc_entries == NULL) {
540 warnx(cache_enable_str, alloc_err, "data");
541 FREE(uc, struct cl_cache, 1);
542 mutex_unlock(&dupreq_lock);
545 MEMZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
546 uc->uc_fifo = ALLOC(cache_ptr, size);
547 if (uc->uc_fifo == NULL) {
548 warnx(cache_enable_str, alloc_err, "fifo");
549 FREE(uc->uc_entries, cache_ptr, size * SPARSENESS);
550 FREE(uc, struct cl_cache, 1);
551 mutex_unlock(&dupreq_lock);
554 MEMZERO(uc->uc_fifo, cache_ptr, size);
555 su->su_cache = (char *)(void *)uc;
556 mutex_unlock(&dupreq_lock);
561 * Set an entry in the cache. It assumes that the uc entry is set from
562 * the earlier call to cache_get() for the same procedure. This will always
563 * happen because cache_get() is calle by svc_dg_recv and cache_set() is called
564 * by svc_dg_reply(). All this hoopla because the right RPC parameters are
565 * not available at svc_dg_reply time.
568 static const char cache_set_str[] = "cache_set: %s";
569 static const char cache_set_err1[] = "victim not found";
570 static const char cache_set_err2[] = "victim alloc failed";
571 static const char cache_set_err3[] = "could not allocate new rpc buffer";
574 cache_set(SVCXPRT *xprt, size_t replylen)
578 struct svc_dg_data *su = su_data(xprt);
579 struct cl_cache *uc = (struct cl_cache *) su->su_cache;
582 #ifdef RPC_CACHE_DEBUG
583 struct netconfig *nconf;
587 mutex_lock(&dupreq_lock);
589 * Find space for the new entry, either by
590 * reusing an old entry, or by mallocing a new one
592 victim = uc->uc_fifo[uc->uc_nextvictim];
593 if (victim != NULL) {
594 loc = CACHE_LOC(xprt, victim->cache_xid);
595 for (vicp = &uc->uc_entries[loc];
596 *vicp != NULL && *vicp != victim;
597 vicp = &(*vicp)->cache_next)
600 warnx(cache_set_str, cache_set_err1);
601 mutex_unlock(&dupreq_lock);
604 *vicp = victim->cache_next; /* remove from cache */
605 newbuf = victim->cache_reply;
607 victim = ALLOC(struct cache_node, 1);
608 if (victim == NULL) {
609 warnx(cache_set_str, cache_set_err2);
610 mutex_unlock(&dupreq_lock);
613 newbuf = mem_alloc(su->su_iosz);
614 if (newbuf == NULL) {
615 warnx(cache_set_str, cache_set_err3);
616 FREE(victim, struct cache_node, 1);
617 mutex_unlock(&dupreq_lock);
625 #ifdef RPC_CACHE_DEBUG
626 if (nconf = getnetconfigent(xprt->xp_netid)) {
627 uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
628 freenetconfigent(nconf);
630 "cache set for xid= %x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
631 su->su_xid, uc->uc_prog, uc->uc_vers,
636 victim->cache_replylen = replylen;
637 victim->cache_reply = rpc_buffer(xprt);
638 rpc_buffer(xprt) = newbuf;
639 xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt),
640 su->su_iosz, XDR_ENCODE);
641 victim->cache_xid = su->su_xid;
642 victim->cache_proc = uc->uc_proc;
643 victim->cache_vers = uc->uc_vers;
644 victim->cache_prog = uc->uc_prog;
645 victim->cache_addr = xprt->xp_rtaddr;
646 victim->cache_addr.buf = ALLOC(char, xprt->xp_rtaddr.len);
647 (void) memcpy(victim->cache_addr.buf, xprt->xp_rtaddr.buf,
648 (size_t)xprt->xp_rtaddr.len);
649 loc = CACHE_LOC(xprt, victim->cache_xid);
650 victim->cache_next = uc->uc_entries[loc];
651 uc->uc_entries[loc] = victim;
652 uc->uc_fifo[uc->uc_nextvictim++] = victim;
653 uc->uc_nextvictim %= uc->uc_size;
654 mutex_unlock(&dupreq_lock);
658 * Try to get an entry from the cache
659 * return 1 if found, 0 if not found and set the stage for cache_set()
662 cache_get(SVCXPRT *xprt, struct rpc_msg *msg, char **replyp, size_t *replylenp)
666 struct svc_dg_data *su = su_data(xprt);
667 struct cl_cache *uc = (struct cl_cache *) su->su_cache;
668 #ifdef RPC_CACHE_DEBUG
669 struct netconfig *nconf;
673 mutex_lock(&dupreq_lock);
674 loc = CACHE_LOC(xprt, su->su_xid);
675 for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
676 if (ent->cache_xid == su->su_xid &&
677 ent->cache_proc == msg->rm_call.cb_proc &&
678 ent->cache_vers == msg->rm_call.cb_vers &&
679 ent->cache_prog == msg->rm_call.cb_prog &&
680 ent->cache_addr.len == xprt->xp_rtaddr.len &&
681 (memcmp(ent->cache_addr.buf, xprt->xp_rtaddr.buf,
682 xprt->xp_rtaddr.len) == 0)) {
683 #ifdef RPC_CACHE_DEBUG
684 if (nconf = getnetconfigent(xprt->xp_netid)) {
685 uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
686 freenetconfigent(nconf);
688 "cache entry found for xid=%x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
689 su->su_xid, msg->rm_call.cb_prog,
690 msg->rm_call.cb_vers,
691 msg->rm_call.cb_proc, uaddr);
695 *replyp = ent->cache_reply;
696 *replylenp = ent->cache_replylen;
697 mutex_unlock(&dupreq_lock);
702 * Failed to find entry
703 * Remember a few things so we can do a set later
705 uc->uc_proc = msg->rm_call.cb_proc;
706 uc->uc_vers = msg->rm_call.cb_vers;
707 uc->uc_prog = msg->rm_call.cb_prog;
708 mutex_unlock(&dupreq_lock);