rpc.subproj/svc_udp.c

   1 /*
   2  * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * Portions Copyright (c) 1999 Apple Computer, Inc.  All Rights
   7  * Reserved.  This file contains Original Code and/or Modifications of
   8  * Original Code as defined in and that are subject to the Apple Public
   9  * Source License Version 1.1 (the "License").  You may not use this file
  10  * except in compliance with the License.  Please obtain a copy of the
  11  * License at http://www.apple.com/publicsource and read it before using
  12  * this file.
  13  *
  14  * The Original Code and all software distributed under the License are
  15  * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  16  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  17  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE OR NON- INFRINGEMENT.  Please see the
  19  * License for the specific language governing rights and limitations
  20  * under the License.
  21  *
  22  * @APPLE_LICENSE_HEADER_END@
  23  */
  24 /*
  25  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
  26  * unrestricted use provided that this legend is included on all tape
  27  * media and as a part of the software program in whole or part.  Users
  28  * may copy or modify Sun RPC without charge, but are not authorized
  29  * to license or distribute it to anyone else except as part of a product or
  30  * program developed by the user.
  31  *
  32  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
  33  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
  34  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
  35  *
  36  * Sun RPC is provided with no support and without any obligation on the
  37  * part of Sun Microsystems, Inc. to assist in its use, correction,
  38  * modification or enhancement.
  39  *
  40  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
  41  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
  42  * OR ANY PART THEREOF.
  43  *
  44  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
  45  * or profits or other special, indirect and consequential damages, even if
  46  * Sun has been advised of the possibility of such damages.
  47  *
  48  * Sun Microsystems, Inc.
  49  * 2550 Garcia Avenue
  50  * Mountain View, California  94043
  51  */
  52
  53 #if defined(LIBC_SCCS) && !defined(lint)
  54 /*static char *sccsid = "from: @(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";*/
  55 /*static char *sccsid = "from: @(#)svc_udp.c    2.2 88/07/29 4.0 RPCSRC";*/
  56 static char *rcsid = "$Id: svc_udp.c,v 1.5 2004/10/13 00:24:07 jkh Exp $";
  57 #endif
  58
  59 /*
  60  * svc_udp.c,
  61  * Server side for UDP/IP based RPC.  (Does some caching in the hopes of
  62  * achieving execute-at-most-once semantics.)
  63  *
  64  * Copyright (C) 1984, Sun Microsystems, Inc.
  65  */
  66
  67 #include <stdio.h>
  68 #include <stdlib.h>
  69 #include <stdint.h>
  70 #include <string.h>
  71 #include <unistd.h>
  72 #include <rpc/rpc.h>
  73 #include <sys/socket.h>
  74 #include <sys/param.h>
  75 #include <errno.h>
  76
  77 extern int              bindresvport();
  78
  79 #define rpc_buffer(xprt) ((xprt)->xp_p1)
  80
  81 static bool_t           svcudp_recv();
  82 static bool_t           svcudp_reply();
  83 static enum xprt_stat   svcudp_stat();
  84 static bool_t           svcudp_getargs();
  85 static bool_t           svcudp_freeargs();
  86 static void             svcudp_destroy();
  87
  88 static struct xp_ops svcudp_op = {
  89         svcudp_recv,
  90         svcudp_stat,
  91         svcudp_getargs,
  92         svcudp_reply,
  93         svcudp_freeargs,
  94         svcudp_destroy
  95 };
  96
  97 extern int errno;
  98
  99 /*
 100  * kept in xprt->xp_p2
 101  */
 102 struct svcudp_data {
 103         u_int   su_iosz;        /* byte size of send.recv buffer */
 104 #ifdef __LP64__
 105         uint32_t        su_xid;         /* transaction id */
 106 #else
 107         u_long  su_xid;         /* transaction id */
 108 #endif
 109         XDR     su_xdrs;        /* XDR handle */
 110         char    su_verfbody[MAX_AUTH_BYTES];    /* verifier body */
 111         char *  su_cache;       /* cached data, NULL if no cache */
 112 };
 113 #define su_data(xprt)   ((struct svcudp_data *)(xprt->xp_p2))
 114
 115 /*
 116  * Usage:
 117  *      xprt = svcudp_create(sock);
 118  *
 119  * If sock<0 then a socket is created, else sock is used.
 120  * If the socket, sock is not bound to a port then svcudp_create
 121  * binds it to an arbitrary port.  In any (successful) case,
 122  * xprt->xp_sock is the registered socket number and xprt->xp_port is the
 123  * associated port number.
 124  * Once *xprt is initialized, it is registered as a transporter;
 125  * see (svc.h, xprt_register).
 126  * The routines returns NULL if a problem occurred.
 127  */
 128 SVCXPRT *
 129 svcudp_bufcreate(sock, sendsz, recvsz)
 130         register int sock;
 131         u_int sendsz, recvsz;
 132 {
 133         bool_t madesock = FALSE;
 134         register SVCXPRT *xprt;
 135         register struct svcudp_data *su;
 136         struct sockaddr_in addr;
 137         unsigned int len = sizeof(struct sockaddr_in);
 138
 139         if (sock == RPC_ANYSOCK) {
 140                 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
 141                         perror("svcudp_create: socket creation problem");
 142                         return ((SVCXPRT *)NULL);
 143                 }
 144                 madesock = TRUE;
 145         }
 146         bzero((char *)&addr, sizeof (addr));
 147         addr.sin_family = AF_INET;
 148         if (bindresvport(sock, &addr)) {
 149                 addr.sin_port = 0;
 150                 (void)bind(sock, (struct sockaddr *)&addr, len);
 151         }
 152         if (getsockname(sock, (struct sockaddr *)&addr, &len) != 0) {
 153                 perror("svcudp_create - cannot getsockname");
 154                 if (madesock)
 155                         (void)close(sock);
 156                 return ((SVCXPRT *)NULL);
 157         }
 158         xprt = (SVCXPRT *)mem_alloc(sizeof(SVCXPRT));
 159         if (xprt == NULL) {
 160                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 161                 return (NULL);
 162         }
 163         su = (struct svcudp_data *)mem_alloc(sizeof(*su));
 164         if (su == NULL) {
 165                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 166                 return (NULL);
 167         }
 168         su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
 169         if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
 170                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 171                 return (NULL);
 172         }
 173         xdrmem_create(
 174             &(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
 175         su->su_cache = NULL;
 176         xprt->xp_p2 = (caddr_t)su;
 177         xprt->xp_verf.oa_base = su->su_verfbody;
 178         xprt->xp_ops = &svcudp_op;
 179         xprt->xp_port = ntohs(addr.sin_port);
 180         xprt->xp_sock = sock;
 181         xprt_register(xprt);
 182         return (xprt);
 183 }
 184
 185 SVCXPRT *
 186 svcudp_create(sock)
 187         int sock;
 188 {
 189
 190         return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
 191 }
 192
 193 static enum xprt_stat
 194 svcudp_stat(xprt)
 195         SVCXPRT *xprt;
 196 {
 197
 198         return (XPRT_IDLE);
 199 }
 200
 201 static int cache_get();
 202 static void cache_set();
 203
 204 static bool_t
 205 svcudp_recv(xprt, msg)
 206         register SVCXPRT *xprt;
 207         struct rpc_msg *msg;
 208 {
 209         register struct svcudp_data *su = su_data(xprt);
 210         register XDR *xdrs = &(su->su_xdrs);
 211         register int rlen;
 212         char *reply;
 213 #ifdef __LP64__
 214         uint32_t replylen;
 215 #else
 216         u_long replylen;
 217 #endif
 218
 219     again:
 220         xprt->xp_addrlen = sizeof(struct sockaddr_in);
 221         rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz, 0, (struct sockaddr *)&(xprt->xp_raddr), (unsigned int *)&(xprt->xp_addrlen));
 222         if (rlen == -1 && errno == EINTR)
 223                 goto again;
 224 #ifdef __LP64__
 225         if (rlen < 4*sizeof(uint32_t))
 226                 return (FALSE);
 227 #else
 228         if (rlen < 4*sizeof(u_long))
 229                 return (FALSE);
 230 #endif
 231         xdrs->x_op = XDR_DECODE;
 232         XDR_SETPOS(xdrs, 0);
 233         if (! xdr_callmsg(xdrs, msg))
 234                 return (FALSE);
 235         su->su_xid = msg->rm_xid;
 236         if (su->su_cache != NULL) {
 237                 if (cache_get(xprt, msg, &reply, &replylen)) {
 238                         (void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
 239                           (struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
 240                         return (TRUE);
 241                 }
 242         }
 243         return (TRUE);
 244 }
 245
 246 static bool_t
 247 svcudp_reply(xprt, msg)
 248         register SVCXPRT *xprt;
 249         struct rpc_msg *msg;
 250 {
 251         register struct svcudp_data *su = su_data(xprt);
 252         register XDR *xdrs = &(su->su_xdrs);
 253         register int slen;
 254         register bool_t stat = FALSE;
 255
 256         xdrs->x_op = XDR_ENCODE;
 257         XDR_SETPOS(xdrs, 0);
 258         msg->rm_xid = su->su_xid;
 259         if (xdr_replymsg(xdrs, msg)) {
 260                 slen = (int)XDR_GETPOS(xdrs);
 261                 if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
 262                     (struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
 263                     == slen) {
 264                         stat = TRUE;
 265                         if (su->su_cache && slen >= 0) {
 266 #ifdef __LP64__
 267                                 cache_set(xprt, (uint32_t) slen);
 268 #else
 269                                 cache_set(xprt, (u_long) slen);
 270 #endif
 271                         }
 272                 }
 273         }
 274         return (stat);
 275 }
 276
 277 static bool_t
 278 svcudp_getargs(xprt, xdr_args, args_ptr)
 279         SVCXPRT *xprt;
 280         xdrproc_t xdr_args;
 281         caddr_t args_ptr;
 282 {
 283
 284         return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr));
 285 }
 286
 287 static bool_t
 288 svcudp_freeargs(xprt, xdr_args, args_ptr)
 289         SVCXPRT *xprt;
 290         xdrproc_t xdr_args;
 291         caddr_t args_ptr;
 292 {
 293         register XDR *xdrs = &(su_data(xprt)->su_xdrs);
 294
 295         xdrs->x_op = XDR_FREE;
 296         return ((*xdr_args)(xdrs, args_ptr));
 297 }
 298
 299 static void
 300 svcudp_destroy(xprt)
 301         register SVCXPRT *xprt;
 302 {
 303         register struct svcudp_data *su = su_data(xprt);
 304
 305         xprt_unregister(xprt);
 306         (void)close(xprt->xp_sock);
 307         XDR_DESTROY(&(su->su_xdrs));
 308         mem_free(rpc_buffer(xprt), su->su_iosz);
 309         mem_free((caddr_t)su, sizeof(struct svcudp_data));
 310         mem_free((caddr_t)xprt, sizeof(SVCXPRT));
 311 }
 312
 313
 314 /***********this could be a separate file*********************/
 315
 316 /*
 317  * Fifo cache for udp server
 318  * Copies pointers to reply buffers into fifo cache
 319  * Buffers are sent again if retransmissions are detected.
 320  */
 321
 322 #define SPARSENESS 4    /* 75% sparse */
 323
 324 #define CACHE_PERROR(msg)       \
 325         (void) fprintf(stderr,"%s\n", msg)
 326
 327 #define ALLOC(type, size)       \
 328         (type *) mem_alloc((unsigned) (sizeof(type) * (size)))
 329
 330 #define BZERO(addr, type, size)  \
 331         bzero((char *) addr, sizeof(type) * (int) (size))
 332
 333 /*
 334  * An entry in the cache
 335  */
 336 typedef struct cache_node *cache_ptr;
 337 struct cache_node {
 338         /*
 339          * Index into cache is xid, proc, vers, prog and address
 340          */
 341 #ifdef __LP64__
 342         uint32_t cache_xid;
 343         uint32_t cache_proc;
 344         uint32_t cache_vers;
 345         uint32_t cache_prog;
 346 #else
 347         u_long cache_xid;
 348         u_long cache_proc;
 349         u_long cache_vers;
 350         u_long cache_prog;
 351 #endif
 352         struct sockaddr_in cache_addr;
 353         /*
 354          * The cached reply and length
 355          */
 356         char * cache_reply;
 357 #ifdef __LP64__
 358         uint32_t cache_replylen;
 359 #else
 360         u_long cache_replylen;
 361 #endif
 362         /*
 363          * Next node on the list, if there is a collision
 364          */
 365         cache_ptr cache_next;
 366 };
 367
 368
 369
 370 /*
 371  * The entire cache
 372  */
 373 struct udp_cache {
 374 #ifdef __LP64__
 375         uint32_t uc_size;               /* size of cache */
 376 #else
 377         u_long uc_size;         /* size of cache */
 378 #endif
 379         cache_ptr *uc_entries;  /* hash table of entries in cache */
 380         cache_ptr *uc_fifo;     /* fifo list of entries in cache */
 381 #ifdef __LP64__
 382         uint32_t uc_nextvictim; /* points to next victim in fifo list */
 383         uint32_t uc_prog;               /* saved program number */
 384         uint32_t uc_vers;               /* saved version number */
 385         uint32_t uc_proc;               /* saved procedure number */
 386 #else
 387         u_long uc_nextvictim;   /* points to next victim in fifo list */
 388         u_long uc_prog;         /* saved program number */
 389         u_long uc_vers;         /* saved version number */
 390         u_long uc_proc;         /* saved procedure number */
 391 #endif
 392         struct sockaddr_in uc_addr; /* saved caller's address */
 393 };
 394
 395
 396 /*
 397  * the hashing function
 398  */
 399 #define CACHE_LOC(transp, xid)  \
 400  (xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
 401
 402
 403 /*
 404  * Enable use of the cache.
 405  * Note: there is no disable.
 406  */
 407 int
 408 svcudp_enablecache(transp, size)
 409         SVCXPRT *transp;
 410 #ifdef __LP64__
 411         uint32_t size;
 412 #else
 413         u_long size;
 414 #endif
 415 {
 416         struct svcudp_data *su = su_data(transp);
 417         struct udp_cache *uc;
 418
 419         if (su->su_cache != NULL) {
 420                 CACHE_PERROR("enablecache: cache already enabled");
 421                 return(0);
 422         }
 423         uc = ALLOC(struct udp_cache, 1);
 424         if (uc == NULL) {
 425                 CACHE_PERROR("enablecache: could not allocate cache");
 426                 return(0);
 427         }
 428         uc->uc_size = size;
 429         uc->uc_nextvictim = 0;
 430         uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
 431         if (uc->uc_entries == NULL) {
 432                 CACHE_PERROR("enablecache: could not allocate cache data");
 433                 return(0);
 434         }
 435         BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
 436         uc->uc_fifo = ALLOC(cache_ptr, size);
 437         if (uc->uc_fifo == NULL) {
 438                 CACHE_PERROR("enablecache: could not allocate cache fifo");
 439                 return(0);
 440         }
 441         BZERO(uc->uc_fifo, cache_ptr, size);
 442         su->su_cache = (char *) uc;
 443         return(1);
 444 }
 445
 446
 447 /*
 448  * Set an entry in the cache
 449  */
 450 static void
 451 cache_set(xprt, replylen)
 452         SVCXPRT *xprt;
 453 #ifdef __LP64__
 454         uint32_t replylen;
 455 #else
 456         u_long replylen;
 457 #endif
 458 {
 459         register cache_ptr victim;
 460         register cache_ptr *vicp;
 461         register struct svcudp_data *su = su_data(xprt);
 462         struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 463         u_int loc;
 464         char *newbuf;
 465
 466         /*
 467          * Find space for the new entry, either by
 468          * reusing an old entry, or by mallocing a new one
 469          */
 470         victim = uc->uc_fifo[uc->uc_nextvictim];
 471         if (victim != NULL) {
 472                 loc = CACHE_LOC(xprt, victim->cache_xid);
 473                 for (vicp = &uc->uc_entries[loc];
 474                   *vicp != NULL && *vicp != victim;
 475                   vicp = &(*vicp)->cache_next)
 476                                 ;
 477                 if (*vicp == NULL) {
 478                         CACHE_PERROR("cache_set: victim not found");
 479                         return;
 480                 }
 481                 *vicp = victim->cache_next;     /* remote from cache */
 482                 newbuf = victim->cache_reply;
 483         } else {
 484                 victim = ALLOC(struct cache_node, 1);
 485                 if (victim == NULL) {
 486                         CACHE_PERROR("cache_set: victim alloc failed");
 487                         return;
 488                 }
 489                 newbuf = mem_alloc(su->su_iosz);
 490                 if (newbuf == NULL) {
 491                         CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
 492                         return;
 493                 }
 494         }
 495
 496         /*
 497          * Store it away
 498          */
 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), su->su_iosz, XDR_ENCODE);
 503         victim->cache_xid = su->su_xid;
 504         victim->cache_proc = uc->uc_proc;
 505         victim->cache_vers = uc->uc_vers;
 506         victim->cache_prog = uc->uc_prog;
 507         victim->cache_addr = uc->uc_addr;
 508         loc = CACHE_LOC(xprt, victim->cache_xid);
 509         victim->cache_next = uc->uc_entries[loc];
 510         uc->uc_entries[loc] = victim;
 511         uc->uc_fifo[uc->uc_nextvictim++] = victim;
 512         uc->uc_nextvictim %= uc->uc_size;
 513 }
 514
 515 /*
 516  * Try to get an entry from the cache
 517  * return 1 if found, 0 if not found
 518  */
 519 static int
 520 cache_get(xprt, msg, replyp, replylenp)
 521         SVCXPRT *xprt;
 522         struct rpc_msg *msg;
 523         char **replyp;
 524 #ifdef __LP64__
 525         uint32_t *replylenp;
 526 #else
 527         u_long *replylenp;
 528 #endif
 529 {
 530         u_int loc;
 531         register cache_ptr ent;
 532         register struct svcudp_data *su = su_data(xprt);
 533         register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 534
 535 #       define EQADDR(a1, a2)   (bcmp((char*)&a1, (char*)&a2, sizeof(a1)) == 0)
 536
 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 == uc->uc_proc &&
 541                   ent->cache_vers == uc->uc_vers &&
 542                   ent->cache_prog == uc->uc_prog &&
 543                   EQADDR(ent->cache_addr, uc->uc_addr)) {
 544                         *replyp = ent->cache_reply;
 545                         *replylenp = ent->cache_replylen;
 546                         return(1);
 547                 }
 548         }
 549         /*
 550          * Failed to find entry
 551          * Remember a few things so we can do a set later
 552          */
 553         uc->uc_proc = msg->rm_call.cb_proc;
 554         uc->uc_vers = msg->rm_call.cb_vers;
 555         uc->uc_prog = msg->rm_call.cb_prog;
 556         uc->uc_addr = xprt->xp_raddr;
 557         return(0);
 558 }
 559