lib/libc/rpc/svc_dg.c

   1 /*
   2  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
   3  * unrestricted use provided that this legend is included on all tape
   4  * media and as a part of the software program in whole or part.  Users
   5  * may copy or modify Sun RPC without charge, but are not authorized
   6  * to license or distribute it to anyone else except as part of a product or
   7  * program developed by the user.
   8  *
   9  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  10  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  11  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  12  *
  13  * Sun RPC is provided with no support and without any obligation on the
  14  * part of Sun Microsystems, Inc. to assist in its use, correction,
  15  * modification or enhancement.
  16  *
  17  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  18  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  19  * OR ANY PART THEREOF.
  20  *
  21  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  22  * or profits or other special, indirect and consequential damages, even if
  23  * Sun has been advised of the possibility of such damages.
  24  *
  25  * Sun Microsystems, Inc.
  26  * 2550 Garcia Avenue
  27  * Mountain View, California  94043
  28  *
  29  * @(#)svc_dg.c 1.17    94/04/24 SMI
  30  * $NetBSD: svc_dg.c,v 1.4 2000/07/06 03:10:35 christos Exp $
  31  * $FreeBSD: src/lib/libc/rpc/svc_dg.c,v 1.8 2006/02/27 22:10:59 deischen Exp $
  32  * $DragonFly$
  33  */
  34
  35 /*
  36  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
  37  */
  38
  39 /*
  40  * svc_dg.c, Server side for connectionless RPC.
  41  *
  42  * Does some caching in the hopes of achieving execute-at-most-once semantics.
  43  */
  44
  45 #include "namespace.h"
  46 #include "reentrant.h"
  47 #include <sys/types.h>
  48 #include <sys/socket.h>
  49 #include <rpc/rpc.h>
  50 #include <rpc/svc_dg.h>
  51 #include <errno.h>
  52 #include <unistd.h>
  53 #include <stdio.h>
  54 #include <stdlib.h>
  55 #include <string.h>
  56 #ifdef RPC_CACHE_DEBUG
  57 #include <netconfig.h>
  58 #include <netdir.h>
  59 #endif
  60 #include <err.h>
  61 #include "un-namespace.h"
  62
  63 #include "rpc_com.h"
  64 #include "mt_misc.h"
  65
  66 #define su_data(xprt)   ((struct svc_dg_data *)(xprt->xp_p2))
  67 #define rpc_buffer(xprt) ((xprt)->xp_p1)
  68
  69 #ifndef MAX
  70 #define MAX(a, b)       (((a) > (b)) ? (a) : (b))
  71 #endif
  72
  73 static void svc_dg_ops(SVCXPRT *);
  74 static enum xprt_stat svc_dg_stat(SVCXPRT *);
  75 static bool_t svc_dg_recv(SVCXPRT *, struct rpc_msg *);
  76 static bool_t svc_dg_reply(SVCXPRT *, struct rpc_msg *);
  77 static bool_t svc_dg_getargs(SVCXPRT *, xdrproc_t, void *);
  78 static bool_t svc_dg_freeargs(SVCXPRT *, xdrproc_t, void *);
  79 static void svc_dg_destroy(SVCXPRT *);
  80 static bool_t svc_dg_control(SVCXPRT *, const u_int, void *);
  81 static int cache_get(SVCXPRT *, struct rpc_msg *, char **, size_t *);
  82 static void cache_set(SVCXPRT *, size_t);
  83 int svc_dg_enablecache(SVCXPRT *, u_int);
  84
  85 /*
  86  * Usage:
  87  *      xprt = svc_dg_create(sock, sendsize, recvsize);
  88  * Does other connectionless specific initializations.
  89  * Once *xprt is initialized, it is registered.
  90  * see (svc.h, xprt_register). If recvsize or sendsize are 0 suitable
  91  * system defaults are chosen.
  92  * The routines returns NULL if a problem occurred.
  93  */
  94 static const char svc_dg_str[] = "svc_dg_create: %s";
  95 static const char svc_dg_err1[] = "could not get transport information";
  96 static const char svc_dg_err2[] = " transport does not support data transfer";
  97 static const char __no_mem_str[] = "out of memory";
  98
  99 SVCXPRT *
 100 svc_dg_create(int fd, u_int sendsize, u_int recvsize)
 101 {
 102         SVCXPRT *xprt;
 103         struct svc_dg_data *su = NULL;
 104         struct __rpc_sockinfo si;
 105         struct sockaddr_storage ss;
 106         socklen_t slen;
 107
 108         if (!__rpc_fd2sockinfo(fd, &si)) {
 109                 warnx(svc_dg_str, svc_dg_err1);
 110                 return (NULL);
 111         }
 112         /*
 113          * Find the receive and the send size
 114          */
 115         sendsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsize);
 116         recvsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsize);
 117         if ((sendsize == 0) || (recvsize == 0)) {
 118                 warnx(svc_dg_str, svc_dg_err2);
 119                 return (NULL);
 120         }
 121
 122         xprt = mem_alloc(sizeof (SVCXPRT));
 123         if (xprt == NULL)
 124                 goto freedata;
 125         memset(xprt, 0, sizeof (SVCXPRT));
 126
 127         su = mem_alloc(sizeof (*su));
 128         if (su == NULL)
 129                 goto freedata;
 130         su->su_iosz = ((MAX(sendsize, recvsize) + 3) / 4) * 4;
 131         if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL)
 132                 goto freedata;
 133         xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
 134                 XDR_DECODE);
 135         su->su_cache = NULL;
 136         xprt->xp_fd = fd;
 137         xprt->xp_p2 = su;
 138         xprt->xp_verf.oa_base = su->su_verfbody;
 139         svc_dg_ops(xprt);
 140         xprt->xp_rtaddr.maxlen = sizeof (struct sockaddr_storage);
 141
 142         slen = sizeof ss;
 143         if (_getsockname(fd, (struct sockaddr *)(void *)&ss, &slen) < 0)
 144                 goto freedata;
 145         xprt->xp_ltaddr.buf = mem_alloc(sizeof (struct sockaddr_storage));
 146         xprt->xp_ltaddr.maxlen = sizeof (struct sockaddr_storage);
 147         xprt->xp_ltaddr.len = slen;
 148         memcpy(xprt->xp_ltaddr.buf, &ss, slen);
 149
 150         xprt_register(xprt);
 151         return (xprt);
 152 freedata:
 153         warnx(svc_dg_str, __no_mem_str);
 154         if (xprt) {
 155                 if (su)
 156                         mem_free(su, sizeof (*su));
 157                 mem_free(xprt, sizeof (SVCXPRT));
 158         }
 159         return (NULL);
 160 }
 161
 162 /*ARGSUSED*/
 163 static enum xprt_stat
 164 svc_dg_stat(SVCXPRT *xprt)
 165 {
 166         return (XPRT_IDLE);
 167 }
 168
 169 static bool_t
 170 svc_dg_recv(SVCXPRT *xprt, struct rpc_msg *msg)
 171 {
 172         struct svc_dg_data *su = su_data(xprt);
 173         XDR *xdrs = &(su->su_xdrs);
 174         char *reply;
 175         struct sockaddr_storage ss;
 176         socklen_t alen;
 177         size_t replylen;
 178         ssize_t rlen;
 179
 180 again:
 181         alen = sizeof (struct sockaddr_storage);
 182         rlen = _recvfrom(xprt->xp_fd, rpc_buffer(xprt), su->su_iosz, 0,
 183             (struct sockaddr *)(void *)&ss, &alen);
 184         if (rlen == -1 && errno == EINTR)
 185                 goto again;
 186         if (rlen == -1 || (rlen < (ssize_t)(4 * sizeof (u_int32_t))))
 187                 return (FALSE);
 188         if (xprt->xp_rtaddr.len < alen) {
 189                 if (xprt->xp_rtaddr.len != 0)
 190                         mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.len);
 191                 xprt->xp_rtaddr.buf = mem_alloc(alen);
 192                 xprt->xp_rtaddr.len = alen;
 193         }
 194         memcpy(xprt->xp_rtaddr.buf, &ss, alen);
 195 #ifdef PORTMAP
 196         if (ss.ss_family == AF_INET) {
 197                 xprt->xp_raddr = *(struct sockaddr_in *)xprt->xp_rtaddr.buf;
 198                 xprt->xp_addrlen = sizeof (struct sockaddr_in);
 199         }
 200 #endif                          /* PORTMAP */
 201         xdrs->x_op = XDR_DECODE;
 202         XDR_SETPOS(xdrs, 0);
 203         if (! xdr_callmsg(xdrs, msg)) {
 204                 return (FALSE);
 205         }
 206         su->su_xid = msg->rm_xid;
 207         if (su->su_cache != NULL) {
 208                 if (cache_get(xprt, msg, &reply, &replylen)) {
 209                         _sendto(xprt->xp_fd, reply, replylen, 0,
 210                             (struct sockaddr *)(void *)&ss, alen);
 211                         return (FALSE);
 212                 }
 213         }
 214         return (TRUE);
 215 }
 216
 217 static bool_t
 218 svc_dg_reply(SVCXPRT *xprt, struct rpc_msg *msg)
 219 {
 220         struct svc_dg_data *su = su_data(xprt);
 221         XDR *xdrs = &(su->su_xdrs);
 222         bool_t stat = FALSE;
 223         size_t slen;
 224
 225         xdrs->x_op = XDR_ENCODE;
 226         XDR_SETPOS(xdrs, 0);
 227         msg->rm_xid = su->su_xid;
 228         if (xdr_replymsg(xdrs, msg)) {
 229                 slen = XDR_GETPOS(xdrs);
 230                 if (_sendto(xprt->xp_fd, rpc_buffer(xprt), slen, 0,
 231                     (struct sockaddr *)xprt->xp_rtaddr.buf,
 232                     (socklen_t)xprt->xp_rtaddr.len) == (ssize_t) slen) {
 233                         stat = TRUE;
 234                         if (su->su_cache)
 235                                 cache_set(xprt, slen);
 236                 }
 237         }
 238         return (stat);
 239 }
 240
 241 static bool_t
 242 svc_dg_getargs(SVCXPRT *xprt, xdrproc_t xdr_args, void *args_ptr)
 243 {
 244         return (*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr);
 245 }
 246
 247 static bool_t
 248 svc_dg_freeargs(SVCXPRT *xprt, xdrproc_t xdr_args, void *args_ptr)
 249 {
 250         XDR *xdrs = &(su_data(xprt)->su_xdrs);
 251
 252         xdrs->x_op = XDR_FREE;
 253         return (*xdr_args)(xdrs, args_ptr);
 254 }
 255
 256 static void
 257 svc_dg_destroy(SVCXPRT *xprt)
 258 {
 259         struct svc_dg_data *su = su_data(xprt);
 260
 261         xprt_unregister(xprt);
 262         if (xprt->xp_fd != -1)
 263                 _close(xprt->xp_fd);
 264         XDR_DESTROY(&(su->su_xdrs));
 265         mem_free(rpc_buffer(xprt), su->su_iosz);
 266         mem_free(su, sizeof (*su));
 267         if (xprt->xp_rtaddr.buf)
 268                 mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.maxlen);
 269         if (xprt->xp_ltaddr.buf)
 270                 mem_free(xprt->xp_ltaddr.buf, xprt->xp_ltaddr.maxlen);
 271         if (xprt->xp_tp)
 272                 free(xprt->xp_tp);
 273         mem_free(xprt, sizeof (SVCXPRT));
 274 }
 275
 276 static bool_t
 277 /*ARGSUSED*/
 278 svc_dg_control(SVCXPRT *xprt, const u_int rq, void *in)
 279 {
 280         return (FALSE);
 281 }
 282
 283 static void
 284 svc_dg_ops(SVCXPRT *xprt)
 285 {
 286         static struct xp_ops ops;
 287         static struct xp_ops2 ops2;
 288
 289 /* VARIABLES PROTECTED BY ops_lock: ops */
 290
 291         mutex_lock(&ops_lock);
 292         if (ops.xp_recv == NULL) {
 293                 ops.xp_recv = svc_dg_recv;
 294                 ops.xp_stat = svc_dg_stat;
 295                 ops.xp_getargs = svc_dg_getargs;
 296                 ops.xp_reply = svc_dg_reply;
 297                 ops.xp_freeargs = svc_dg_freeargs;
 298                 ops.xp_destroy = svc_dg_destroy;
 299                 ops2.xp_control = svc_dg_control;
 300         }
 301         xprt->xp_ops = &ops;
 302         xprt->xp_ops2 = &ops2;
 303         mutex_unlock(&ops_lock);
 304 }
 305
 306 /*  The CACHING COMPONENT */
 307
 308 /*
 309  * Could have been a separate file, but some part of it depends upon the
 310  * private structure of the client handle.
 311  *
 312  * Fifo cache for cl server
 313  * Copies pointers to reply buffers into fifo cache
 314  * Buffers are sent again if retransmissions are detected.
 315  */
 316
 317 #define SPARSENESS 4    /* 75% sparse */
 318
 319 #define ALLOC(type, size)       \
 320         (type *) mem_alloc((sizeof (type) * (size)))
 321
 322 #define MEMZERO(addr, type, size)        \
 323         memset((void *) (addr), 0, sizeof (type) * (int) (size))
 324
 325 #define FREE(addr, type, size)  \
 326         mem_free((addr), (sizeof (type) * (size)))
 327
 328 /*
 329  * An entry in the cache
 330  */
 331 typedef struct cache_node *cache_ptr;
 332 struct cache_node {
 333         /*
 334          * Index into cache is xid, proc, vers, prog and address
 335          */
 336         u_int32_t cache_xid;
 337         rpcproc_t cache_proc;
 338         rpcvers_t cache_vers;
 339         rpcprog_t cache_prog;
 340         struct netbuf cache_addr;
 341         /*
 342          * The cached reply and length
 343          */
 344         char *cache_reply;
 345         size_t cache_replylen;
 346         /*
 347          * Next node on the list, if there is a collision
 348          */
 349         cache_ptr cache_next;
 350 };
 351
 352 /*
 353  * The entire cache
 354  */
 355 struct cl_cache {
 356         u_int uc_size;          /* size of cache */
 357         cache_ptr *uc_entries;  /* hash table of entries in cache */
 358         cache_ptr *uc_fifo;     /* fifo list of entries in cache */
 359         u_int uc_nextvictim;    /* points to next victim in fifo list */
 360         rpcprog_t uc_prog;      /* saved program number */
 361         rpcvers_t uc_vers;      /* saved version number */
 362         rpcproc_t uc_proc;      /* saved procedure number */
 363 };
 364
 365
 366 /*
 367  * the hashing function
 368  */
 369 #define CACHE_LOC(transp, xid)  \
 370         (xid % (SPARSENESS * ((struct cl_cache *) \
 371                 su_data(transp)->su_cache)->uc_size))
 372
 373 /*
 374  * Enable use of the cache. Returns 1 on success, 0 on failure.
 375  * Note: there is no disable.
 376  */
 377 static const char cache_enable_str[] = "svc_enablecache: %s %s";
 378 static const char alloc_err[] = "could not allocate cache ";
 379 static const char enable_err[] = "cache already enabled";
 380
 381 int
 382 svc_dg_enablecache(SVCXPRT *transp, u_int size)
 383 {
 384         struct svc_dg_data *su = su_data(transp);
 385         struct cl_cache *uc;
 386
 387         mutex_lock(&dupreq_lock);
 388         if (su->su_cache != NULL) {
 389                 warnx(cache_enable_str, enable_err, " ");
 390                 mutex_unlock(&dupreq_lock);
 391                 return (0);
 392         }
 393         uc = ALLOC(struct cl_cache, 1);
 394         if (uc == NULL) {
 395                 warnx(cache_enable_str, alloc_err, " ");
 396                 mutex_unlock(&dupreq_lock);
 397                 return (0);
 398         }
 399         uc->uc_size = size;
 400         uc->uc_nextvictim = 0;
 401         uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
 402         if (uc->uc_entries == NULL) {
 403                 warnx(cache_enable_str, alloc_err, "data");
 404                 FREE(uc, struct cl_cache, 1);
 405                 mutex_unlock(&dupreq_lock);
 406                 return (0);
 407         }
 408         MEMZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
 409         uc->uc_fifo = ALLOC(cache_ptr, size);
 410         if (uc->uc_fifo == NULL) {
 411                 warnx(cache_enable_str, alloc_err, "fifo");
 412                 FREE(uc->uc_entries, cache_ptr, size * SPARSENESS);
 413                 FREE(uc, struct cl_cache, 1);
 414                 mutex_unlock(&dupreq_lock);
 415                 return (0);
 416         }
 417         MEMZERO(uc->uc_fifo, cache_ptr, size);
 418         su->su_cache = (char *)(void *)uc;
 419         mutex_unlock(&dupreq_lock);
 420         return (1);
 421 }
 422
 423 /*
 424  * Set an entry in the cache.  It assumes that the uc entry is set from
 425  * the earlier call to cache_get() for the same procedure.  This will always
 426  * happen because cache_get() is calle by svc_dg_recv and cache_set() is called
 427  * by svc_dg_reply().  All this hoopla because the right RPC parameters are
 428  * not available at svc_dg_reply time.
 429  */
 430
 431 static const char cache_set_str[] = "cache_set: %s";
 432 static const char cache_set_err1[] = "victim not found";
 433 static const char cache_set_err2[] = "victim alloc failed";
 434 static const char cache_set_err3[] = "could not allocate new rpc buffer";
 435
 436 static void
 437 cache_set(SVCXPRT *xprt, size_t replylen)
 438 {
 439         cache_ptr victim;
 440         cache_ptr *vicp;
 441         struct svc_dg_data *su = su_data(xprt);
 442         struct cl_cache *uc = (struct cl_cache *) su->su_cache;
 443         u_int loc;
 444         char *newbuf;
 445 #ifdef RPC_CACHE_DEBUG
 446         struct netconfig *nconf;
 447         char *uaddr;
 448 #endif
 449
 450         mutex_lock(&dupreq_lock);
 451         /*
 452          * Find space for the new entry, either by
 453          * reusing an old entry, or by mallocing a new one
 454          */
 455         victim = uc->uc_fifo[uc->uc_nextvictim];
 456         if (victim != NULL) {
 457                 loc = CACHE_LOC(xprt, victim->cache_xid);
 458                 for (vicp = &uc->uc_entries[loc];
 459                         *vicp != NULL && *vicp != victim;
 460                         vicp = &(*vicp)->cache_next)
 461                         ;
 462                 if (*vicp == NULL) {
 463                         warnx(cache_set_str, cache_set_err1);
 464                         mutex_unlock(&dupreq_lock);
 465                         return;
 466                 }
 467                 *vicp = victim->cache_next;     /* remove from cache */
 468                 newbuf = victim->cache_reply;
 469         } else {
 470                 victim = ALLOC(struct cache_node, 1);
 471                 if (victim == NULL) {
 472                         warnx(cache_set_str, cache_set_err2);
 473                         mutex_unlock(&dupreq_lock);
 474                         return;
 475                 }
 476                 newbuf = mem_alloc(su->su_iosz);
 477                 if (newbuf == NULL) {
 478                         warnx(cache_set_str, cache_set_err3);
 479                         FREE(victim, struct cache_node, 1);
 480                         mutex_unlock(&dupreq_lock);
 481                         return;
 482                 }
 483         }
 484
 485         /*
 486          * Store it away
 487          */
 488 #ifdef RPC_CACHE_DEBUG
 489         if (nconf = getnetconfigent(xprt->xp_netid)) {
 490                 uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
 491                 freenetconfigent(nconf);
 492                 printf(
 493         "cache set for xid= %x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
 494                         su->su_xid, uc->uc_prog, uc->uc_vers,
 495                         uc->uc_proc, uaddr);
 496                 free(uaddr);
 497         }
 498 #endif
 499         victim->cache_replylen = replylen;
 500         victim->cache_reply = rpc_buffer(xprt);
 501         rpc_buffer(xprt) = newbuf;
 502         xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt),
 503                         su->su_iosz, XDR_ENCODE);
 504         victim->cache_xid = su->su_xid;
 505         victim->cache_proc = uc->uc_proc;
 506         victim->cache_vers = uc->uc_vers;
 507         victim->cache_prog = uc->uc_prog;
 508         victim->cache_addr = xprt->xp_rtaddr;
 509         victim->cache_addr.buf = ALLOC(char, xprt->xp_rtaddr.len);
 510         memcpy(victim->cache_addr.buf, xprt->xp_rtaddr.buf,
 511             (size_t)xprt->xp_rtaddr.len);
 512         loc = CACHE_LOC(xprt, victim->cache_xid);
 513         victim->cache_next = uc->uc_entries[loc];
 514         uc->uc_entries[loc] = victim;
 515         uc->uc_fifo[uc->uc_nextvictim++] = victim;
 516         uc->uc_nextvictim %= uc->uc_size;
 517         mutex_unlock(&dupreq_lock);
 518 }
 519
 520 /*
 521  * Try to get an entry from the cache
 522  * return 1 if found, 0 if not found and set the stage for cache_set()
 523  */
 524 static int
 525 cache_get(SVCXPRT *xprt, struct rpc_msg *msg, char **replyp, size_t *replylenp)
 526 {
 527         u_int loc;
 528         cache_ptr ent;
 529         struct svc_dg_data *su = su_data(xprt);
 530         struct cl_cache *uc = (struct cl_cache *) su->su_cache;
 531 #ifdef RPC_CACHE_DEBUG
 532         struct netconfig *nconf;
 533         char *uaddr;
 534 #endif
 535
 536         mutex_lock(&dupreq_lock);
 537         loc = CACHE_LOC(xprt, su->su_xid);
 538         for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
 539                 if (ent->cache_xid == su->su_xid &&
 540                         ent->cache_proc == msg->rm_call.cb_proc &&
 541                         ent->cache_vers == msg->rm_call.cb_vers &&
 542                         ent->cache_prog == msg->rm_call.cb_prog &&
 543                         ent->cache_addr.len == xprt->xp_rtaddr.len &&
 544                         (memcmp(ent->cache_addr.buf, xprt->xp_rtaddr.buf,
 545                                 xprt->xp_rtaddr.len) == 0)) {
 546 #ifdef RPC_CACHE_DEBUG
 547                         if (nconf = getnetconfigent(xprt->xp_netid)) {
 548                                 uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
 549                                 freenetconfigent(nconf);
 550                                 printf(
 551         "cache entry found for xid=%x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
 552                                         su->su_xid, msg->rm_call.cb_prog,
 553                                         msg->rm_call.cb_vers,
 554                                         msg->rm_call.cb_proc, uaddr);
 555                                 free(uaddr);
 556                         }
 557 #endif
 558                         *replyp = ent->cache_reply;
 559                         *replylenp = ent->cache_replylen;
 560                         mutex_unlock(&dupreq_lock);
 561                         return (1);
 562                 }
 563         }
 564         /*
 565          * Failed to find entry
 566          * Remember a few things so we can do a set later
 567          */
 568         uc->uc_proc = msg->rm_call.cb_proc;
 569         uc->uc_vers = msg->rm_call.cb_vers;
 570         uc->uc_prog = msg->rm_call.cb_prog;
 571         mutex_unlock(&dupreq_lock);
 572         return (0);
 573 }