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[glibc.git] / sunrpc / svc_udp.c
blob04c8407e64e17475a78fa5f28def0bb3e43aa029
1 /*
2 * svc_udp.c,
3 * Server side for UDP/IP based RPC. (Does some caching in the hopes of
4 * achieving execute-at-most-once semantics.)
6 * Copyright (c) 2010, Oracle America, Inc.
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are
10 * met:
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * * Redistributions in binary form must reproduce the above
15 * copyright notice, this list of conditions and the following
16 * disclaimer in the documentation and/or other materials
17 * provided with the distribution.
18 * * Neither the name of the "Oracle America, Inc." nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific prior written permission.
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
27 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
29 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
33 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 #include <stdio.h>
37 #include <unistd.h>
38 #include <string.h>
39 #include <rpc/rpc.h>
40 #include <sys/socket.h>
41 #include <errno.h>
42 #include <libintl.h>
44 #ifdef IP_PKTINFO
45 #include <sys/uio.h>
46 #endif
48 #include <wchar.h>
49 #include <libio/iolibio.h>
51 #define rpc_buffer(xprt) ((xprt)->xp_p1)
52 #ifndef MAX
53 #define MAX(a, b) ((a > b) ? a : b)
54 #endif
56 static bool_t svcudp_recv (SVCXPRT *, struct rpc_msg *);
57 static bool_t svcudp_reply (SVCXPRT *, struct rpc_msg *);
58 static enum xprt_stat svcudp_stat (SVCXPRT *);
59 static bool_t svcudp_getargs (SVCXPRT *, xdrproc_t, caddr_t);
60 static bool_t svcudp_freeargs (SVCXPRT *, xdrproc_t, caddr_t);
61 static void svcudp_destroy (SVCXPRT *);
63 static const struct xp_ops svcudp_op =
65 svcudp_recv,
66 svcudp_stat,
67 svcudp_getargs,
68 svcudp_reply,
69 svcudp_freeargs,
70 svcudp_destroy
73 static int cache_get (SVCXPRT *, struct rpc_msg *, char **replyp,
74 u_long *replylenp);
75 static void cache_set (SVCXPRT *xprt, u_long replylen);
78 * kept in xprt->xp_p2
80 struct svcudp_data
82 u_int su_iosz; /* byte size of send.recv buffer */
83 u_long su_xid; /* transaction id */
84 XDR su_xdrs; /* XDR handle */
85 char su_verfbody[MAX_AUTH_BYTES]; /* verifier body */
86 char *su_cache; /* cached data, NULL if no cache */
88 #define su_data(xprt) ((struct svcudp_data *)(xprt->xp_p2))
91 * Usage:
92 * xprt = svcudp_create(sock);
94 * If sock<0 then a socket is created, else sock is used.
95 * If the socket, sock is not bound to a port then svcudp_create
96 * binds it to an arbitrary port. In any (successful) case,
97 * xprt->xp_sock is the registered socket number and xprt->xp_port is the
98 * associated port number.
99 * Once *xprt is initialized, it is registered as a transporter;
100 * see (svc.h, xprt_register).
101 * The routines returns NULL if a problem occurred.
103 SVCXPRT *
104 svcudp_bufcreate (sock, sendsz, recvsz)
105 int sock;
106 u_int sendsz, recvsz;
108 bool_t madesock = FALSE;
109 SVCXPRT *xprt;
110 struct svcudp_data *su;
111 struct sockaddr_in addr;
112 socklen_t len = sizeof (struct sockaddr_in);
113 int pad;
114 void *buf;
116 if (sock == RPC_ANYSOCK)
118 if ((sock = __socket (AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
120 perror (_("svcudp_create: socket creation problem"));
121 return (SVCXPRT *) NULL;
123 madesock = TRUE;
125 __bzero ((char *) &addr, sizeof (addr));
126 addr.sin_family = AF_INET;
127 if (bindresvport (sock, &addr))
129 addr.sin_port = 0;
130 (void) __bind (sock, (struct sockaddr *) &addr, len);
132 if (__getsockname (sock, (struct sockaddr *) &addr, &len) != 0)
134 perror (_("svcudp_create - cannot getsockname"));
135 if (madesock)
136 (void) __close (sock);
137 return (SVCXPRT *) NULL;
139 xprt = (SVCXPRT *) mem_alloc (sizeof (SVCXPRT));
140 su = (struct svcudp_data *) mem_alloc (sizeof (*su));
141 buf = mem_alloc (((MAX (sendsz, recvsz) + 3) / 4) * 4);
142 if (xprt == NULL || su == NULL || buf == NULL)
144 (void) __fxprintf (NULL, "%s: %s",
145 "svcudp_create", _("out of memory\n"));
146 mem_free (xprt, sizeof (SVCXPRT));
147 mem_free (su, sizeof (*su));
148 mem_free (buf, ((MAX (sendsz, recvsz) + 3) / 4) * 4);
149 return NULL;
151 su->su_iosz = ((MAX (sendsz, recvsz) + 3) / 4) * 4;
152 rpc_buffer (xprt) = buf;
153 xdrmem_create (&(su->su_xdrs), rpc_buffer (xprt), su->su_iosz, XDR_DECODE);
154 su->su_cache = NULL;
155 xprt->xp_p2 = (caddr_t) su;
156 xprt->xp_verf.oa_base = su->su_verfbody;
157 xprt->xp_ops = &svcudp_op;
158 xprt->xp_port = ntohs (addr.sin_port);
159 xprt->xp_sock = sock;
161 #ifdef IP_PKTINFO
162 if ((sizeof (struct iovec) + sizeof (struct msghdr)
163 + sizeof(struct cmsghdr) + sizeof (struct in_pktinfo))
164 > sizeof (xprt->xp_pad))
166 (void) __fxprintf (NULL,"%s", _("\
167 svcudp_create: xp_pad is too small for IP_PKTINFO\n"));
168 return NULL;
170 pad = 1;
171 if (__setsockopt (sock, SOL_IP, IP_PKTINFO, (void *) &pad,
172 sizeof (pad)) == 0)
173 /* Set the padding to all 1s. */
174 pad = 0xff;
175 else
176 #endif
177 /* Clear the padding. */
178 pad = 0;
179 memset (&xprt->xp_pad [0], pad, sizeof (xprt->xp_pad));
181 xprt_register (xprt);
182 return xprt;
184 #ifdef EXPORT_RPC_SYMBOLS
185 libc_hidden_def (svcudp_bufcreate)
186 #else
187 libc_hidden_nolink (svcudp_bufcreate, GLIBC_2_0)
188 #endif
190 SVCXPRT *
191 svcudp_create (sock)
192 int sock;
194 return svcudp_bufcreate (sock, UDPMSGSIZE, UDPMSGSIZE);
196 #ifdef EXPORT_RPC_SYMBOLS
197 libc_hidden_def (svcudp_create)
198 #else
199 libc_hidden_nolink (svcudp_create, GLIBC_2_0)
200 #endif
202 static enum xprt_stat
203 svcudp_stat (xprt)
204 SVCXPRT *xprt;
207 return XPRT_IDLE;
210 static bool_t
211 svcudp_recv (xprt, msg)
212 SVCXPRT *xprt;
213 struct rpc_msg *msg;
215 struct svcudp_data *su = su_data (xprt);
216 XDR *xdrs = &(su->su_xdrs);
217 int rlen;
218 char *reply;
219 u_long replylen;
220 socklen_t len;
222 /* It is very tricky when you have IP aliases. We want to make sure
223 that we are sending the packet from the IP address where the
224 incoming packet is addressed to. H.J. */
225 #ifdef IP_PKTINFO
226 struct iovec *iovp;
227 struct msghdr *mesgp;
228 #endif
230 again:
231 /* FIXME -- should xp_addrlen be a size_t? */
232 len = (socklen_t) sizeof(struct sockaddr_in);
233 #ifdef IP_PKTINFO
234 iovp = (struct iovec *) &xprt->xp_pad [0];
235 mesgp = (struct msghdr *) &xprt->xp_pad [sizeof (struct iovec)];
236 if (mesgp->msg_iovlen)
238 iovp->iov_base = rpc_buffer (xprt);
239 iovp->iov_len = su->su_iosz;
240 mesgp->msg_iov = iovp;
241 mesgp->msg_iovlen = 1;
242 mesgp->msg_name = &(xprt->xp_raddr);
243 mesgp->msg_namelen = len;
244 mesgp->msg_control = &xprt->xp_pad [sizeof (struct iovec)
245 + sizeof (struct msghdr)];
246 mesgp->msg_controllen = sizeof(xprt->xp_pad)
247 - sizeof (struct iovec) - sizeof (struct msghdr);
248 rlen = __recvmsg (xprt->xp_sock, mesgp, 0);
249 if (rlen >= 0)
251 struct cmsghdr *cmsg;
252 len = mesgp->msg_namelen;
253 cmsg = CMSG_FIRSTHDR (mesgp);
254 if (cmsg == NULL
255 || CMSG_NXTHDR (mesgp, cmsg) != NULL
256 || cmsg->cmsg_level != SOL_IP
257 || cmsg->cmsg_type != IP_PKTINFO
258 || cmsg->cmsg_len < (sizeof (struct cmsghdr)
259 + sizeof (struct in_pktinfo)))
261 /* Not a simple IP_PKTINFO, ignore it. */
262 mesgp->msg_control = NULL;
263 mesgp->msg_controllen = 0;
265 else
267 /* It was a simple IP_PKTIFO as we expected, discard the
268 interface field. */
269 struct in_pktinfo *pkti = (struct in_pktinfo *) CMSG_DATA (cmsg);
270 pkti->ipi_ifindex = 0;
274 else
275 #endif
276 rlen = __recvfrom (xprt->xp_sock, rpc_buffer (xprt),
277 (int) su->su_iosz, 0,
278 (struct sockaddr *) &(xprt->xp_raddr), &len);
279 xprt->xp_addrlen = len;
280 if (rlen == -1 && errno == EINTR)
281 goto again;
282 if (rlen < 16) /* < 4 32-bit ints? */
283 return FALSE;
284 xdrs->x_op = XDR_DECODE;
285 XDR_SETPOS (xdrs, 0);
286 if (!xdr_callmsg (xdrs, msg))
287 return FALSE;
288 su->su_xid = msg->rm_xid;
289 if (su->su_cache != NULL)
291 if (cache_get (xprt, msg, &reply, &replylen))
293 #ifdef IP_PKTINFO
294 if (mesgp->msg_iovlen)
296 iovp->iov_base = reply;
297 iovp->iov_len = replylen;
298 (void) __sendmsg (xprt->xp_sock, mesgp, 0);
300 else
301 #endif
302 (void) __sendto (xprt->xp_sock, reply, (int) replylen, 0,
303 (struct sockaddr *) &xprt->xp_raddr, len);
304 return TRUE;
307 return TRUE;
310 static bool_t
311 svcudp_reply (xprt, msg)
312 SVCXPRT *xprt;
313 struct rpc_msg *msg;
315 struct svcudp_data *su = su_data (xprt);
316 XDR *xdrs = &(su->su_xdrs);
317 int slen, sent;
318 bool_t stat = FALSE;
319 #ifdef IP_PKTINFO
320 struct iovec *iovp;
321 struct msghdr *mesgp;
322 #endif
324 xdrs->x_op = XDR_ENCODE;
325 XDR_SETPOS (xdrs, 0);
326 msg->rm_xid = su->su_xid;
327 if (xdr_replymsg (xdrs, msg))
329 slen = (int) XDR_GETPOS (xdrs);
330 #ifdef IP_PKTINFO
331 mesgp = (struct msghdr *) &xprt->xp_pad [sizeof (struct iovec)];
332 if (mesgp->msg_iovlen)
334 iovp = (struct iovec *) &xprt->xp_pad [0];
335 iovp->iov_base = rpc_buffer (xprt);
336 iovp->iov_len = slen;
337 sent = __sendmsg (xprt->xp_sock, mesgp, 0);
339 else
340 #endif
341 sent = __sendto (xprt->xp_sock, rpc_buffer (xprt), slen, 0,
342 (struct sockaddr *) &(xprt->xp_raddr),
343 xprt->xp_addrlen);
344 if (sent == slen)
346 stat = TRUE;
347 if (su->su_cache && slen >= 0)
349 cache_set (xprt, (u_long) slen);
353 return stat;
356 static bool_t
357 svcudp_getargs (xprt, xdr_args, args_ptr)
358 SVCXPRT *xprt;
359 xdrproc_t xdr_args;
360 caddr_t args_ptr;
363 return (*xdr_args) (&(su_data (xprt)->su_xdrs), args_ptr);
366 static bool_t
367 svcudp_freeargs (xprt, xdr_args, args_ptr)
368 SVCXPRT *xprt;
369 xdrproc_t xdr_args;
370 caddr_t args_ptr;
372 XDR *xdrs = &(su_data (xprt)->su_xdrs);
374 xdrs->x_op = XDR_FREE;
375 return (*xdr_args) (xdrs, args_ptr);
378 static void
379 svcudp_destroy (xprt)
380 SVCXPRT *xprt;
382 struct svcudp_data *su = su_data (xprt);
384 xprt_unregister (xprt);
385 (void) __close (xprt->xp_sock);
386 XDR_DESTROY (&(su->su_xdrs));
387 mem_free (rpc_buffer (xprt), su->su_iosz);
388 mem_free ((caddr_t) su, sizeof (struct svcudp_data));
389 mem_free ((caddr_t) xprt, sizeof (SVCXPRT));
393 /***********this could be a separate file*********************/
396 * Fifo cache for udp server
397 * Copies pointers to reply buffers into fifo cache
398 * Buffers are sent again if retransmissions are detected.
401 #define SPARSENESS 4 /* 75% sparse */
403 #define CACHE_PERROR(msg) \
404 (void) __fxprintf(NULL, "%s\n", msg)
406 #define ALLOC(type, size) \
407 (type *) mem_alloc((unsigned) (sizeof(type) * (size)))
409 #define CALLOC(type, size) \
410 (type *) calloc (sizeof (type), size)
413 * An entry in the cache
415 typedef struct cache_node *cache_ptr;
416 struct cache_node
419 * Index into cache is xid, proc, vers, prog and address
421 u_long cache_xid;
422 u_long cache_proc;
423 u_long cache_vers;
424 u_long cache_prog;
425 struct sockaddr_in cache_addr;
427 * The cached reply and length
429 char *cache_reply;
430 u_long cache_replylen;
432 * Next node on the list, if there is a collision
434 cache_ptr cache_next;
440 * The entire cache
442 struct udp_cache
444 u_long uc_size; /* size of cache */
445 cache_ptr *uc_entries; /* hash table of entries in cache */
446 cache_ptr *uc_fifo; /* fifo list of entries in cache */
447 u_long uc_nextvictim; /* points to next victim in fifo list */
448 u_long uc_prog; /* saved program number */
449 u_long uc_vers; /* saved version number */
450 u_long uc_proc; /* saved procedure number */
451 struct sockaddr_in uc_addr; /* saved caller's address */
456 * the hashing function
458 #define CACHE_LOC(transp, xid) \
459 (xid % (SPARSENESS*((struct udp_cache *) su_data(transp)->su_cache)->uc_size))
463 * Enable use of the cache.
464 * Note: there is no disable.
467 svcudp_enablecache (SVCXPRT *transp, u_long size)
469 struct svcudp_data *su = su_data (transp);
470 struct udp_cache *uc;
472 if (su->su_cache != NULL)
474 CACHE_PERROR (_("enablecache: cache already enabled"));
475 return 0;
477 uc = ALLOC (struct udp_cache, 1);
478 if (uc == NULL)
480 CACHE_PERROR (_("enablecache: could not allocate cache"));
481 return 0;
483 uc->uc_size = size;
484 uc->uc_nextvictim = 0;
485 uc->uc_entries = CALLOC (cache_ptr, size * SPARSENESS);
486 if (uc->uc_entries == NULL)
488 mem_free (uc, sizeof (struct udp_cache));
489 CACHE_PERROR (_("enablecache: could not allocate cache data"));
490 return 0;
492 uc->uc_fifo = CALLOC (cache_ptr, size);
493 if (uc->uc_fifo == NULL)
495 mem_free (uc->uc_entries, size * SPARSENESS);
496 mem_free (uc, sizeof (struct udp_cache));
497 CACHE_PERROR (_("enablecache: could not allocate cache fifo"));
498 return 0;
500 su->su_cache = (char *) uc;
501 return 1;
503 libc_hidden_nolink (svcudp_enablecache, GLIBC_2_0)
507 * Set an entry in the cache
509 static void
510 cache_set (SVCXPRT *xprt, u_long replylen)
512 cache_ptr victim;
513 cache_ptr *vicp;
514 struct svcudp_data *su = su_data (xprt);
515 struct udp_cache *uc = (struct udp_cache *) su->su_cache;
516 u_int loc;
517 char *newbuf;
520 * Find space for the new entry, either by
521 * reusing an old entry, or by mallocing a new one
523 victim = uc->uc_fifo[uc->uc_nextvictim];
524 if (victim != NULL)
526 loc = CACHE_LOC (xprt, victim->cache_xid);
527 for (vicp = &uc->uc_entries[loc];
528 *vicp != NULL && *vicp != victim;
529 vicp = &(*vicp)->cache_next)
531 if (*vicp == NULL)
533 CACHE_PERROR (_("cache_set: victim not found"));
534 return;
536 *vicp = victim->cache_next; /* remote from cache */
537 newbuf = victim->cache_reply;
539 else
541 victim = ALLOC (struct cache_node, 1);
542 if (victim == NULL)
544 CACHE_PERROR (_("cache_set: victim alloc failed"));
545 return;
547 newbuf = mem_alloc (su->su_iosz);
548 if (newbuf == NULL)
550 mem_free (victim, sizeof (struct cache_node));
551 CACHE_PERROR (_("cache_set: could not allocate new rpc_buffer"));
552 return;
557 * Store it away
559 victim->cache_replylen = replylen;
560 victim->cache_reply = rpc_buffer (xprt);
561 rpc_buffer (xprt) = newbuf;
562 xdrmem_create (&(su->su_xdrs), rpc_buffer (xprt), su->su_iosz, XDR_ENCODE);
563 victim->cache_xid = su->su_xid;
564 victim->cache_proc = uc->uc_proc;
565 victim->cache_vers = uc->uc_vers;
566 victim->cache_prog = uc->uc_prog;
567 victim->cache_addr = uc->uc_addr;
568 loc = CACHE_LOC (xprt, victim->cache_xid);
569 victim->cache_next = uc->uc_entries[loc];
570 uc->uc_entries[loc] = victim;
571 uc->uc_fifo[uc->uc_nextvictim++] = victim;
572 uc->uc_nextvictim %= uc->uc_size;
576 * Try to get an entry from the cache
577 * return 1 if found, 0 if not found
579 static int
580 cache_get (xprt, msg, replyp, replylenp)
581 SVCXPRT *xprt;
582 struct rpc_msg *msg;
583 char **replyp;
584 u_long *replylenp;
586 u_int loc;
587 cache_ptr ent;
588 struct svcudp_data *su = su_data (xprt);
589 struct udp_cache *uc = (struct udp_cache *) su->su_cache;
591 #define EQADDR(a1, a2) (memcmp((char*)&a1, (char*)&a2, sizeof(a1)) == 0)
593 loc = CACHE_LOC (xprt, su->su_xid);
594 for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next)
596 if (ent->cache_xid == su->su_xid &&
597 ent->cache_proc == uc->uc_proc &&
598 ent->cache_vers == uc->uc_vers &&
599 ent->cache_prog == uc->uc_prog &&
600 EQADDR (ent->cache_addr, uc->uc_addr))
602 *replyp = ent->cache_reply;
603 *replylenp = ent->cache_replylen;
604 return 1;
608 * Failed to find entry
609 * Remember a few things so we can do a set later
611 uc->uc_proc = msg->rm_call.cb_proc;
612 uc->uc_vers = msg->rm_call.cb_vers;
613 uc->uc_prog = msg->rm_call.cb_prog;
614 memcpy (&uc->uc_addr, &xprt->xp_raddr, sizeof (uc->uc_addr));
615 return 0;