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                 mem_free(xprt, sizeof(SVCXPRT));
 166                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 167                 return (NULL);
 168         }
 169         su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
 170         if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
 171                 mem_free(xprt, sizeof(SVCXPRT));
 172                 mem_free(su, sizeof(*su));
 173                 (void)fprintf(stderr, "svcudp_create: out of memory\n");
 174                 return (NULL);
 175         }
 176         xdrmem_create(
 177             &(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
 178         su->su_cache = NULL;
 179         xprt->xp_p2 = (caddr_t)su;
 180         xprt->xp_verf.oa_base = su->su_verfbody;
 181         xprt->xp_ops = &svcudp_op;
 182         xprt->xp_port = ntohs(addr.sin_port);
 183         xprt->xp_sock = sock;
 184         xprt_register(xprt);
 185         return (xprt);
 186 }
 187
 188 SVCXPRT *
 189 svcudp_create(sock)
 190         int sock;
 191 {
 192
 193         return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
 194 }
 195
 196 static enum xprt_stat
 197 svcudp_stat(xprt)
 198         SVCXPRT *xprt;
 199 {
 200
 201         return (XPRT_IDLE);
 202 }
 203
 204 static int cache_get();
 205 static void cache_set();
 206
 207 static bool_t
 208 svcudp_recv(xprt, msg)
 209         register SVCXPRT *xprt;
 210         struct rpc_msg *msg;
 211 {
 212         register struct svcudp_data *su = su_data(xprt);
 213         register XDR *xdrs = &(su->su_xdrs);
 214         register int rlen;
 215         char *reply;
 216 #ifdef __LP64__
 217         uint32_t replylen;
 218 #else
 219         u_long replylen;
 220 #endif
 221
 222     again:
 223         xprt->xp_addrlen = sizeof(struct sockaddr_in);
 224         rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz, 0, (struct sockaddr *)&(xprt->xp_raddr), (unsigned int *)&(xprt->xp_addrlen));
 225         if (rlen == -1 && errno == EINTR)
 226                 goto again;
 227 #ifdef __LP64__
 228         if (rlen < 4*sizeof(uint32_t))
 229                 return (FALSE);
 230 #else
 231         if (rlen < 4*sizeof(u_long))
 232                 return (FALSE);
 233 #endif
 234         xdrs->x_op = XDR_DECODE;
 235         XDR_SETPOS(xdrs, 0);
 236         if (! xdr_callmsg(xdrs, msg))
 237                 return (FALSE);
 238         su->su_xid = msg->rm_xid;
 239         if (su->su_cache != NULL) {
 240                 if (cache_get(xprt, msg, &reply, &replylen)) {
 241                         (void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
 242                           (struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
 243                         return (TRUE);
 244                 }
 245         }
 246         return (TRUE);
 247 }
 248
 249 static bool_t
 250 svcudp_reply(xprt, msg)
 251         register SVCXPRT *xprt;
 252         struct rpc_msg *msg;
 253 {
 254         register struct svcudp_data *su = su_data(xprt);
 255         register XDR *xdrs = &(su->su_xdrs);
 256         register int slen;
 257         register bool_t stat = FALSE;
 258
 259         xdrs->x_op = XDR_ENCODE;
 260         XDR_SETPOS(xdrs, 0);
 261         msg->rm_xid = su->su_xid;
 262         if (xdr_replymsg(xdrs, msg)) {
 263                 slen = (int)XDR_GETPOS(xdrs);
 264                 if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
 265                     (struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
 266                     == slen) {
 267                         stat = TRUE;
 268                         if (su->su_cache && slen >= 0) {
 269 #ifdef __LP64__
 270                                 cache_set(xprt, (uint32_t) slen);
 271 #else
 272                                 cache_set(xprt, (u_long) slen);
 273 #endif
 274                         }
 275                 }
 276         }
 277         return (stat);
 278 }
 279
 280 static bool_t
 281 svcudp_getargs(xprt, xdr_args, args_ptr)
 282         SVCXPRT *xprt;
 283         xdrproc_t xdr_args;
 284         caddr_t args_ptr;
 285 {
 286
 287         return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr, 0));
 288 }
 289
 290 static bool_t
 291 svcudp_freeargs(xprt, xdr_args, args_ptr)
 292         SVCXPRT *xprt;
 293         xdrproc_t xdr_args;
 294         caddr_t args_ptr;
 295 {
 296         register XDR *xdrs = &(su_data(xprt)->su_xdrs);
 297
 298         xdrs->x_op = XDR_FREE;
 299         return ((*xdr_args)(xdrs, args_ptr, 0));
 300 }
 301
 302 static void
 303 svcudp_destroy(xprt)
 304         register SVCXPRT *xprt;
 305 {
 306         register struct svcudp_data *su = su_data(xprt);
 307
 308         xprt_unregister(xprt);
 309         (void)close(xprt->xp_sock);
 310         XDR_DESTROY(&(su->su_xdrs));
 311         mem_free(rpc_buffer(xprt), su->su_iosz);
 312         mem_free((caddr_t)su, sizeof(struct svcudp_data));
 313         mem_free((caddr_t)xprt, sizeof(SVCXPRT));
 314 }
 315
 316
 317 /***********this could be a separate file*********************/
 318
 319 /*
 320  * Fifo cache for udp server
 321  * Copies pointers to reply buffers into fifo cache
 322  * Buffers are sent again if retransmissions are detected.
 323  */
 324
 325 #define SPARSENESS 4    /* 75% sparse */
 326
 327 #define CACHE_PERROR(msg)       \
 328         (void) fprintf(stderr,"%s\n", msg)
 329
 330 #define ALLOC(type, size)       \
 331         (type *) mem_alloc((unsigned) (sizeof(type) * (size)))
 332
 333 #define BZERO(addr, type, size)  \
 334         bzero((char *) addr, sizeof(type) * (int) (size))
 335
 336 /*
 337  * An entry in the cache
 338  */
 339 typedef struct cache_node *cache_ptr;
 340 struct cache_node {
 341         /*
 342          * Index into cache is xid, proc, vers, prog and address
 343          */
 344 #ifdef __LP64__
 345         uint32_t cache_xid;
 346         uint32_t cache_proc;
 347         uint32_t cache_vers;
 348         uint32_t cache_prog;
 349 #else
 350         u_long cache_xid;
 351         u_long cache_proc;
 352         u_long cache_vers;
 353         u_long cache_prog;
 354 #endif
 355         struct sockaddr_in cache_addr;
 356         /*
 357          * The cached reply and length
 358          */
 359         char * cache_reply;
 360 #ifdef __LP64__
 361         uint32_t cache_replylen;
 362 #else
 363         u_long cache_replylen;
 364 #endif
 365         /*
 366          * Next node on the list, if there is a collision
 367          */
 368         cache_ptr cache_next;
 369 };
 370
 371
 372
 373 /*
 374  * The entire cache
 375  */
 376 struct udp_cache {
 377 #ifdef __LP64__
 378         uint32_t uc_size;               /* size of cache */
 379 #else
 380         u_long uc_size;         /* size of cache */
 381 #endif
 382         cache_ptr *uc_entries;  /* hash table of entries in cache */
 383         cache_ptr *uc_fifo;     /* fifo list of entries in cache */
 384 #ifdef __LP64__
 385         uint32_t uc_nextvictim; /* points to next victim in fifo list */
 386         uint32_t uc_prog;               /* saved program number */
 387         uint32_t uc_vers;               /* saved version number */
 388         uint32_t uc_proc;               /* saved procedure number */
 389 #else
 390         u_long uc_nextvictim;   /* points to next victim in fifo list */
 391         u_long uc_prog;         /* saved program number */
 392         u_long uc_vers;         /* saved version number */
 393         u_long uc_proc;         /* saved procedure number */
 394 #endif
 395         struct sockaddr_in uc_addr; /* saved caller's address */
 396 };
 397
 398
 399 /*
 400  * the hashing function
 401  */
 402 #define CACHE_LOC(transp, xid)  \
 403  (xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
 404
 405
 406 /*
 407  * Enable use of the cache.
 408  * Note: there is no disable.
 409  */
 410 int
 411 svcudp_enablecache(transp, size)
 412         SVCXPRT *transp;
 413 #ifdef __LP64__
 414         uint32_t size;
 415 #else
 416         u_long size;
 417 #endif
 418 {
 419         struct svcudp_data *su = su_data(transp);
 420         struct udp_cache *uc;
 421
 422         if (su->su_cache != NULL) {
 423                 CACHE_PERROR("enablecache: cache already enabled");
 424                 return(0);
 425         }
 426         uc = ALLOC(struct udp_cache, 1);
 427         if (uc == NULL) {
 428                 CACHE_PERROR("enablecache: could not allocate cache");
 429                 return(0);
 430         }
 431         uc->uc_size = size;
 432         uc->uc_nextvictim = 0;
 433         uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
 434         if (uc->uc_entries == NULL) {
 435                 mem_free(uc, sizeof(*uc));
 436                 CACHE_PERROR("enablecache: could not allocate cache data");
 437                 return(0);
 438         }
 439         BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
 440         uc->uc_fifo = ALLOC(cache_ptr, size);
 441         if (uc->uc_fifo == NULL) {
 442                 mem_free(uc->uc_entries, sizeof(struct udp_cache)*size * SPARSENESS);
 443                 mem_free(uc, sizeof(struct udp_cache));
 444                 CACHE_PERROR("enablecache: could not allocate cache fifo");
 445                 return(0);
 446         }
 447         BZERO(uc->uc_fifo, cache_ptr, size);
 448         su->su_cache = (char *) uc;
 449         return(1);
 450 }
 451
 452
 453 /*
 454  * Set an entry in the cache
 455  */
 456 static void
 457 cache_set(xprt, replylen)
 458         SVCXPRT *xprt;
 459 #ifdef __LP64__
 460         uint32_t replylen;
 461 #else
 462         u_long replylen;
 463 #endif
 464 {
 465         register cache_ptr victim;
 466         register cache_ptr *vicp;
 467         register struct svcudp_data *su = su_data(xprt);
 468         struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 469         u_int loc;
 470         char *newbuf;
 471
 472         /*
 473          * Find space for the new entry, either by
 474          * reusing an old entry, or by mallocing a new one
 475          */
 476         victim = uc->uc_fifo[uc->uc_nextvictim];
 477         if (victim != NULL) {
 478                 loc = CACHE_LOC(xprt, victim->cache_xid);
 479                 for (vicp = &uc->uc_entries[loc];
 480                   *vicp != NULL && *vicp != victim;
 481                   vicp = &(*vicp)->cache_next)
 482                                 ;
 483                 if (*vicp == NULL) {
 484                         CACHE_PERROR("cache_set: victim not found");
 485                         return;
 486                 }
 487                 *vicp = victim->cache_next;     /* remote from cache */
 488                 newbuf = victim->cache_reply;
 489         } else {
 490                 victim = ALLOC(struct cache_node, 1);
 491                 if (victim == NULL) {
 492                         CACHE_PERROR("cache_set: victim alloc failed");
 493                         return;
 494                 }
 495                 newbuf = mem_alloc(su->su_iosz);
 496                 if (newbuf == NULL) {
 497                         mem_free(victim, sizeof(*victim));
 498                         CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
 499                         return;
 500                 }
 501         }
 502
 503         /*
 504          * Store it away
 505          */
 506         victim->cache_replylen = replylen;
 507         victim->cache_reply = rpc_buffer(xprt);
 508         rpc_buffer(xprt) = newbuf;
 509         xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_ENCODE);
 510         victim->cache_xid = su->su_xid;
 511         victim->cache_proc = uc->uc_proc;
 512         victim->cache_vers = uc->uc_vers;
 513         victim->cache_prog = uc->uc_prog;
 514         victim->cache_addr = uc->uc_addr;
 515         loc = CACHE_LOC(xprt, victim->cache_xid);
 516         victim->cache_next = uc->uc_entries[loc];
 517         uc->uc_entries[loc] = victim;
 518         uc->uc_fifo[uc->uc_nextvictim++] = victim;
 519         uc->uc_nextvictim %= uc->uc_size;
 520 }
 521
 522 /*
 523  * Try to get an entry from the cache
 524  * return 1 if found, 0 if not found
 525  */
 526 static int
 527 cache_get(xprt, msg, replyp, replylenp)
 528         SVCXPRT *xprt;
 529         struct rpc_msg *msg;
 530         char **replyp;
 531 #ifdef __LP64__
 532         uint32_t *replylenp;
 533 #else
 534         u_long *replylenp;
 535 #endif
 536 {
 537         u_int loc;
 538         register cache_ptr ent;
 539         register struct svcudp_data *su = su_data(xprt);
 540         register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
 541
 542 #       define EQADDR(a1, a2)   (bcmp((char*)&a1, (char*)&a2, sizeof(a1)) == 0)
 543
 544         loc = CACHE_LOC(xprt, su->su_xid);
 545         for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
 546                 if (ent->cache_xid == su->su_xid &&
 547                   ent->cache_proc == uc->uc_proc &&
 548                   ent->cache_vers == uc->uc_vers &&
 549                   ent->cache_prog == uc->uc_prog &&
 550                   EQADDR(ent->cache_addr, uc->uc_addr)) {
 551                         *replyp = ent->cache_reply;
 552                         *replylenp = ent->cache_replylen;
 553                         return(1);
 554                 }
 555         }
 556         /*
 557          * Failed to find entry
 558          * Remember a few things so we can do a set later
 559          */
 560         uc->uc_proc = msg->rm_call.cb_proc;
 561         uc->uc_vers = msg->rm_call.cb_vers;
 562         uc->uc_prog = msg->rm_call.cb_prog;
 563         uc->uc_addr = xprt->xp_raddr;
 564         return(0);
 565 }
 566