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.
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.
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.
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.
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.
25 * Sun Microsystems, Inc.
27 * Mountain View, California 94043
30 #if defined(LIBC_SCCS) && !defined(lint)
31 /*static char *sccsid = "from: @(#)svc_udp.c 1.24 87/08/11 Copyr 1984 Sun Micro";*/
32 /*static char *sccsid = "from: @(#)svc_udp.c 2.2 88/07/29 4.0 RPCSRC";*/
33 static char *rcsid = "$FreeBSD: src/lib/libc/rpc/svc_udp.c,v 1.13 2000/01/27 23:06:41 jasone Exp $";
38 * Server side for UDP/IP based RPC. (Does some caching in the hopes of
39 * achieving execute-at-most-once semantics.)
41 * Copyright (C) 1984, Sun Microsystems, Inc.
49 #include <sys/socket.h>
52 #define rpc_buffer(xprt) ((xprt)->xp_p1)
53 #define MAX(a, b) ((a > b) ? a : b)
55 static bool_t svcudp_recv();
56 static bool_t svcudp_reply();
57 static enum xprt_stat svcudp_stat();
58 static bool_t svcudp_getargs();
59 static bool_t svcudp_freeargs();
60 static void svcudp_destroy();
61 static void cache_set __P((SVCXPRT *, u_long));
62 static int cache_get __P((SVCXPRT *, struct rpc_msg *, char **, u_long *));
64 static struct xp_ops svcudp_op = {
77 u_int su_iosz; /* byte size of send.recv buffer */
78 u_long su_xid; /* transaction id */
79 XDR su_xdrs; /* XDR handle */
80 char su_verfbody[MAX_AUTH_BYTES]; /* verifier body */
81 char * su_cache; /* cached data, NULL if no cache */
83 #define su_data(xprt) ((struct svcudp_data *)(xprt->xp_p2))
87 * xprt = svcudp_create(sock);
89 * If sock<0 then a socket is created, else sock is used.
90 * If the socket, sock is not bound to a port then svcudp_create
91 * binds it to an arbitrary port. In any (successful) case,
92 * xprt->xp_sock is the registered socket number and xprt->xp_port is the
93 * associated port number.
94 * Once *xprt is initialized, it is registered as a transporter;
95 * see (svc.h, xprt_register).
96 * The routines returns NULL if a problem occurred.
99 svcudp_bufcreate(sock, sendsz, recvsz)
101 u_int sendsz, recvsz;
103 bool_t madesock = FALSE;
104 register SVCXPRT *xprt;
105 register struct svcudp_data *su;
106 struct sockaddr_in addr;
107 int len = sizeof(struct sockaddr_in);
109 if (sock == RPC_ANYSOCK) {
110 if ((sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0) {
111 perror("svcudp_create: socket creation problem");
112 return ((SVCXPRT *)NULL);
116 memset((char *)&addr, 0, sizeof (addr));
117 addr.sin_len = sizeof(struct sockaddr_in);
118 addr.sin_family = AF_INET;
119 if (bindresvport(sock, &addr)) {
121 (void)bind(sock, (struct sockaddr *)&addr, len);
123 if (getsockname(sock, (struct sockaddr *)&addr, &len) != 0) {
124 perror("svcudp_create - cannot getsockname");
127 return ((SVCXPRT *)NULL);
129 xprt = (SVCXPRT *)mem_alloc(sizeof(SVCXPRT));
131 (void)fprintf(stderr, "svcudp_create: out of memory\n");
134 su = (struct svcudp_data *)mem_alloc(sizeof(*su));
136 (void)fprintf(stderr, "svcudp_create: out of memory\n");
139 su->su_iosz = ((MAX(sendsz, recvsz) + 3) / 4) * 4;
140 if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL) {
141 (void)fprintf(stderr, "svcudp_create: out of memory\n");
145 &(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_DECODE);
147 xprt->xp_p2 = (caddr_t)su;
148 xprt->xp_verf.oa_base = su->su_verfbody;
149 xprt->xp_ops = &svcudp_op;
150 xprt->xp_port = ntohs(addr.sin_port);
151 xprt->xp_sock = sock;
161 return(svcudp_bufcreate(sock, UDPMSGSIZE, UDPMSGSIZE));
164 static enum xprt_stat
173 svcudp_recv(xprt, msg)
174 register SVCXPRT *xprt;
177 register struct svcudp_data *su = su_data(xprt);
178 register XDR *xdrs = &(su->su_xdrs);
184 xprt->xp_addrlen = sizeof(struct sockaddr_in);
185 rlen = recvfrom(xprt->xp_sock, rpc_buffer(xprt), (int) su->su_iosz,
186 0, (struct sockaddr *)&(xprt->xp_raddr), &(xprt->xp_addrlen));
187 if (rlen == -1 && errno == EINTR)
189 if (rlen == -1 || rlen < 4*sizeof(u_int32_t))
191 xdrs->x_op = XDR_DECODE;
193 if (! xdr_callmsg(xdrs, msg))
195 su->su_xid = msg->rm_xid;
196 if (su->su_cache != NULL) {
197 if (cache_get(xprt, msg, &reply, &replylen)) {
198 (void) sendto(xprt->xp_sock, reply, (int) replylen, 0,
199 (struct sockaddr *) &xprt->xp_raddr, xprt->xp_addrlen);
207 svcudp_reply(xprt, msg)
208 register SVCXPRT *xprt;
211 register struct svcudp_data *su = su_data(xprt);
212 register XDR *xdrs = &(su->su_xdrs);
214 register bool_t stat = FALSE;
216 xdrs->x_op = XDR_ENCODE;
218 msg->rm_xid = su->su_xid;
219 if (xdr_replymsg(xdrs, msg)) {
220 slen = (int)XDR_GETPOS(xdrs);
221 if (sendto(xprt->xp_sock, rpc_buffer(xprt), slen, 0,
222 (struct sockaddr *)&(xprt->xp_raddr), xprt->xp_addrlen)
225 if (su->su_cache && slen >= 0) {
226 cache_set(xprt, (u_long) slen);
234 svcudp_getargs(xprt, xdr_args, args_ptr)
240 return ((*xdr_args)(&(su_data(xprt)->su_xdrs), args_ptr));
244 svcudp_freeargs(xprt, xdr_args, args_ptr)
249 register XDR *xdrs = &(su_data(xprt)->su_xdrs);
251 xdrs->x_op = XDR_FREE;
252 return ((*xdr_args)(xdrs, args_ptr));
257 register SVCXPRT *xprt;
259 register struct svcudp_data *su = su_data(xprt);
261 xprt_unregister(xprt);
262 (void)_close(xprt->xp_sock);
263 XDR_DESTROY(&(su->su_xdrs));
264 mem_free(rpc_buffer(xprt), su->su_iosz);
265 mem_free((caddr_t)su, sizeof(struct svcudp_data));
266 mem_free((caddr_t)xprt, sizeof(SVCXPRT));
270 /***********this could be a separate file*********************/
273 * Fifo cache for udp server
274 * Copies pointers to reply buffers into fifo cache
275 * Buffers are sent again if retransmissions are detected.
278 #define SPARSENESS 4 /* 75% sparse */
280 #define CACHE_PERROR(msg) \
281 (void) fprintf(stderr,"%s\n", msg)
283 #define ALLOC(type, size) \
284 (type *) mem_alloc((unsigned) (sizeof(type) * (size)))
286 #define BZERO(addr, type, size) \
287 memset((char *) addr, 0, sizeof(type) * (int) (size))
290 * An entry in the cache
292 typedef struct cache_node *cache_ptr;
295 * Index into cache is xid, proc, vers, prog and address
301 struct sockaddr_in cache_addr;
303 * The cached reply and length
306 u_long cache_replylen;
308 * Next node on the list, if there is a collision
310 cache_ptr cache_next;
319 u_long uc_size; /* size of cache */
320 cache_ptr *uc_entries; /* hash table of entries in cache */
321 cache_ptr *uc_fifo; /* fifo list of entries in cache */
322 u_long uc_nextvictim; /* points to next victim in fifo list */
323 u_long uc_prog; /* saved program number */
324 u_long uc_vers; /* saved version number */
325 u_long uc_proc; /* saved procedure number */
326 struct sockaddr_in uc_addr; /* saved caller's address */
331 * the hashing function
333 #define CACHE_LOC(transp, xid) \
334 (xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
338 * Enable use of the cache.
339 * Note: there is no disable.
341 int svcudp_enablecache(transp, size)
345 struct svcudp_data *su = su_data(transp);
346 struct udp_cache *uc;
348 if (su->su_cache != NULL) {
349 CACHE_PERROR("enablecache: cache already enabled");
352 uc = ALLOC(struct udp_cache, 1);
354 CACHE_PERROR("enablecache: could not allocate cache");
358 uc->uc_nextvictim = 0;
359 uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
360 if (uc->uc_entries == NULL) {
361 CACHE_PERROR("enablecache: could not allocate cache data");
364 BZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
365 uc->uc_fifo = ALLOC(cache_ptr, size);
366 if (uc->uc_fifo == NULL) {
367 CACHE_PERROR("enablecache: could not allocate cache fifo");
370 BZERO(uc->uc_fifo, cache_ptr, size);
371 su->su_cache = (char *) uc;
377 * Set an entry in the cache
380 cache_set(xprt, replylen)
384 register cache_ptr victim;
385 register cache_ptr *vicp;
386 register struct svcudp_data *su = su_data(xprt);
387 struct udp_cache *uc = (struct udp_cache *) su->su_cache;
392 * Find space for the new entry, either by
393 * reusing an old entry, or by mallocing a new one
395 victim = uc->uc_fifo[uc->uc_nextvictim];
396 if (victim != NULL) {
397 loc = CACHE_LOC(xprt, victim->cache_xid);
398 for (vicp = &uc->uc_entries[loc];
399 *vicp != NULL && *vicp != victim;
400 vicp = &(*vicp)->cache_next)
403 CACHE_PERROR("cache_set: victim not found");
406 *vicp = victim->cache_next; /* remote from cache */
407 newbuf = victim->cache_reply;
409 victim = ALLOC(struct cache_node, 1);
410 if (victim == NULL) {
411 CACHE_PERROR("cache_set: victim alloc failed");
414 newbuf = mem_alloc(su->su_iosz);
415 if (newbuf == NULL) {
416 CACHE_PERROR("cache_set: could not allocate new rpc_buffer");
424 victim->cache_replylen = replylen;
425 victim->cache_reply = rpc_buffer(xprt);
426 rpc_buffer(xprt) = newbuf;
427 xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz, XDR_ENCODE);
428 victim->cache_xid = su->su_xid;
429 victim->cache_proc = uc->uc_proc;
430 victim->cache_vers = uc->uc_vers;
431 victim->cache_prog = uc->uc_prog;
432 victim->cache_addr = uc->uc_addr;
433 loc = CACHE_LOC(xprt, victim->cache_xid);
434 victim->cache_next = uc->uc_entries[loc];
435 uc->uc_entries[loc] = victim;
436 uc->uc_fifo[uc->uc_nextvictim++] = victim;
437 uc->uc_nextvictim %= uc->uc_size;
441 * Try to get an entry from the cache
442 * return 1 if found, 0 if not found
445 cache_get(xprt, msg, replyp, replylenp)
452 register cache_ptr ent;
453 register struct svcudp_data *su = su_data(xprt);
454 register struct udp_cache *uc = (struct udp_cache *) su->su_cache;
456 # define EQADDR(a1, a2) (memcmp(&a1, &a2, sizeof(a1)) == 0)
458 loc = CACHE_LOC(xprt, su->su_xid);
459 for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
460 if (ent->cache_xid == su->su_xid &&
461 ent->cache_proc == uc->uc_proc &&
462 ent->cache_vers == uc->uc_vers &&
463 ent->cache_prog == uc->uc_prog &&
464 EQADDR(ent->cache_addr, uc->uc_addr)) {
465 *replyp = ent->cache_reply;
466 *replylenp = ent->cache_replylen;
471 * Failed to find entry
472 * Remember a few things so we can do a set later
474 uc->uc_proc = msg->rm_call.cb_proc;
475 uc->uc_vers = msg->rm_call.cb_vers;
476 uc->uc_prog = msg->rm_call.cb_prog;
477 uc->uc_addr = xprt->xp_raddr;