xref: /freebsd/lib/libc/rpc/svc_dg.c (revision cc16dea626cf2fc80cde667ac4798065108e596c)
1 /*	$NetBSD: svc_dg.c,v 1.4 2000/07/06 03:10:35 christos Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 
32 /*
33  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
34  */
35 
36 #if defined(LIBC_SCCS) && !defined(lint)
37 #ident	"@(#)svc_dg.c	1.17	94/04/24 SMI"
38 #endif
39 #include <sys/cdefs.h>
40 __FBSDID("$FreeBSD$");
41 
42 /*
43  * svc_dg.c, Server side for connectionless RPC.
44  *
45  * Does some caching in the hopes of achieving execute-at-most-once semantics.
46  */
47 
48 #include "namespace.h"
49 #include "reentrant.h"
50 #include <sys/types.h>
51 #include <sys/socket.h>
52 #include <rpc/rpc.h>
53 #include <rpc/svc_dg.h>
54 #include <assert.h>
55 #include <errno.h>
56 #include <unistd.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #ifdef RPC_CACHE_DEBUG
61 #include <netconfig.h>
62 #include <netdir.h>
63 #endif
64 #include <err.h>
65 #include "un-namespace.h"
66 
67 #include "rpc_com.h"
68 #include "mt_misc.h"
69 
70 #define	su_data(xprt)	((struct svc_dg_data *)(xprt->xp_p2))
71 #define	rpc_buffer(xprt) ((xprt)->xp_p1)
72 
73 #ifndef MAX
74 #define	MAX(a, b)	(((a) > (b)) ? (a) : (b))
75 #endif
76 
77 static void svc_dg_ops(SVCXPRT *);
78 static enum xprt_stat svc_dg_stat(SVCXPRT *);
79 static bool_t svc_dg_recv(SVCXPRT *, struct rpc_msg *);
80 static bool_t svc_dg_reply(SVCXPRT *, struct rpc_msg *);
81 static bool_t svc_dg_getargs(SVCXPRT *, xdrproc_t, void *);
82 static bool_t svc_dg_freeargs(SVCXPRT *, xdrproc_t, void *);
83 static void svc_dg_destroy(SVCXPRT *);
84 static bool_t svc_dg_control(SVCXPRT *, const u_int, void *);
85 static int cache_get(SVCXPRT *, struct rpc_msg *, char **, size_t *);
86 static void cache_set(SVCXPRT *, size_t);
87 int svc_dg_enablecache(SVCXPRT *, u_int);
88 
89 /*
90  * Usage:
91  *	xprt = svc_dg_create(sock, sendsize, recvsize);
92  * Does other connectionless specific initializations.
93  * Once *xprt is initialized, it is registered.
94  * see (svc.h, xprt_register). If recvsize or sendsize are 0 suitable
95  * system defaults are chosen.
96  * The routines returns NULL if a problem occurred.
97  */
98 static const char svc_dg_str[] = "svc_dg_create: %s";
99 static const char svc_dg_err1[] = "could not get transport information";
100 static const char svc_dg_err2[] = "transport does not support data transfer";
101 static const char svc_dg_err3[] = "getsockname failed";
102 static const char svc_dg_err4[] = "cannot set IP_RECVDSTADDR";
103 static const char __no_mem_str[] = "out of memory";
104 
105 SVCXPRT *
106 svc_dg_create(fd, sendsize, recvsize)
107 	int fd;
108 	u_int sendsize;
109 	u_int recvsize;
110 {
111 	SVCXPRT *xprt;
112 	struct svc_dg_data *su = NULL;
113 	struct __rpc_sockinfo si;
114 	struct sockaddr_storage ss;
115 	socklen_t slen;
116 
117 	if (!__rpc_fd2sockinfo(fd, &si)) {
118 		warnx(svc_dg_str, svc_dg_err1);
119 		return (NULL);
120 	}
121 	/*
122 	 * Find the receive and the send size
123 	 */
124 	sendsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)sendsize);
125 	recvsize = __rpc_get_t_size(si.si_af, si.si_proto, (int)recvsize);
126 	if ((sendsize == 0) || (recvsize == 0)) {
127 		warnx(svc_dg_str, svc_dg_err2);
128 		return (NULL);
129 	}
130 
131 	xprt = svc_xprt_alloc();
132 	if (xprt == NULL)
133 		goto freedata;
134 
135 	su = mem_alloc(sizeof (*su));
136 	if (su == NULL)
137 		goto freedata;
138 	su->su_iosz = ((MAX(sendsize, recvsize) + 3) / 4) * 4;
139 	if ((rpc_buffer(xprt) = mem_alloc(su->su_iosz)) == NULL)
140 		goto freedata;
141 	xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
142 		XDR_DECODE);
143 	su->su_cache = NULL;
144 	xprt->xp_fd = fd;
145 	xprt->xp_p2 = su;
146 	xprt->xp_verf.oa_base = su->su_verfbody;
147 	svc_dg_ops(xprt);
148 	xprt->xp_rtaddr.maxlen = sizeof (struct sockaddr_storage);
149 
150 	slen = sizeof ss;
151 	if (_getsockname(fd, (struct sockaddr *)(void *)&ss, &slen) < 0) {
152 		warnx(svc_dg_str, svc_dg_err3);
153 		goto freedata_nowarn;
154 	}
155 	xprt->xp_ltaddr.buf = mem_alloc(sizeof (struct sockaddr_storage));
156 	xprt->xp_ltaddr.maxlen = sizeof (struct sockaddr_storage);
157 	xprt->xp_ltaddr.len = slen;
158 	memcpy(xprt->xp_ltaddr.buf, &ss, slen);
159 
160 	if (ss.ss_family == AF_INET) {
161 		struct sockaddr_in *sin;
162 		static const int true_value = 1;
163 
164 		sin = (struct sockaddr_in *)(void *)&ss;
165 		if (sin->sin_addr.s_addr == INADDR_ANY) {
166 		    su->su_srcaddr.buf = mem_alloc(sizeof (ss));
167 		    su->su_srcaddr.maxlen = sizeof (ss);
168 
169 		    if (_setsockopt(fd, IPPROTO_IP, IP_RECVDSTADDR,
170 				    &true_value, sizeof(true_value))) {
171 			    warnx(svc_dg_str,  svc_dg_err4);
172 			    goto freedata_nowarn;
173 		    }
174 		}
175 	}
176 
177 	xprt_register(xprt);
178 	return (xprt);
179 freedata:
180 	(void) warnx(svc_dg_str, __no_mem_str);
181 freedata_nowarn:
182 	if (xprt) {
183 		if (su)
184 			(void) mem_free(su, sizeof (*su));
185 		svc_xprt_free(xprt);
186 	}
187 	return (NULL);
188 }
189 
190 /*ARGSUSED*/
191 static enum xprt_stat
192 svc_dg_stat(xprt)
193 	SVCXPRT *xprt;
194 {
195 	return (XPRT_IDLE);
196 }
197 
198 static int
199 svc_dg_recvfrom(int fd, char *buf, int buflen,
200     struct sockaddr *raddr, socklen_t *raddrlen,
201     struct sockaddr *laddr, socklen_t *laddrlen)
202 {
203 	struct msghdr msg;
204 	struct iovec msg_iov[1];
205 	struct sockaddr_in *lin = (struct sockaddr_in *)laddr;
206 	int rlen;
207 	bool_t have_lin = FALSE;
208 	char tmp[CMSG_LEN(sizeof(*lin))];
209 	struct cmsghdr *cmsg;
210 
211 	memset((char *)&msg, 0, sizeof(msg));
212 	msg_iov[0].iov_base = buf;
213 	msg_iov[0].iov_len = buflen;
214 	msg.msg_iov = msg_iov;
215 	msg.msg_iovlen = 1;
216 	msg.msg_namelen = *raddrlen;
217 	msg.msg_name = (char *)raddr;
218 	if (laddr != NULL) {
219 	    msg.msg_control = (caddr_t)tmp;
220 	    msg.msg_controllen = CMSG_LEN(sizeof(*lin));
221 	}
222 	rlen = _recvmsg(fd, &msg, 0);
223 	if (rlen >= 0)
224 		*raddrlen = msg.msg_namelen;
225 
226 	if (rlen == -1 || laddr == NULL ||
227 	    msg.msg_controllen < sizeof(struct cmsghdr) ||
228 	    msg.msg_flags & MSG_CTRUNC)
229 		return rlen;
230 
231 	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
232 	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
233 		if (cmsg->cmsg_level == IPPROTO_IP &&
234 		    cmsg->cmsg_type == IP_RECVDSTADDR) {
235 			have_lin = TRUE;
236 			memcpy(&lin->sin_addr,
237 			    (struct in_addr *)CMSG_DATA(cmsg),
238 			    sizeof(struct in_addr));
239 			break;
240 		}
241 	}
242 
243 	lin->sin_family = AF_INET;
244 	lin->sin_port = 0;
245 	*laddrlen = sizeof(struct sockaddr_in);
246 
247 	if (!have_lin)
248 		lin->sin_addr.s_addr = INADDR_ANY;
249 
250 	return rlen;
251 }
252 
253 static bool_t
254 svc_dg_recv(xprt, msg)
255 	SVCXPRT *xprt;
256 	struct rpc_msg *msg;
257 {
258 	struct svc_dg_data *su = su_data(xprt);
259 	XDR *xdrs = &(su->su_xdrs);
260 	char *reply;
261 	struct sockaddr_storage ss;
262 	socklen_t alen;
263 	size_t replylen;
264 	ssize_t rlen;
265 
266 again:
267 	alen = sizeof (struct sockaddr_storage);
268 	rlen = svc_dg_recvfrom(xprt->xp_fd, rpc_buffer(xprt), su->su_iosz,
269 	    (struct sockaddr *)(void *)&ss, &alen,
270 	    (struct sockaddr *)su->su_srcaddr.buf, &su->su_srcaddr.len);
271 	if (rlen == -1 && errno == EINTR)
272 		goto again;
273 	if (rlen == -1 || (rlen < (ssize_t)(4 * sizeof (u_int32_t))))
274 		return (FALSE);
275 	if (xprt->xp_rtaddr.len < alen) {
276 		if (xprt->xp_rtaddr.len != 0)
277 			mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.len);
278 		xprt->xp_rtaddr.buf = mem_alloc(alen);
279 		xprt->xp_rtaddr.len = alen;
280 	}
281 	memcpy(xprt->xp_rtaddr.buf, &ss, alen);
282 #ifdef PORTMAP
283 	if (ss.ss_family == AF_INET) {
284 		xprt->xp_raddr = *(struct sockaddr_in *)xprt->xp_rtaddr.buf;
285 		xprt->xp_addrlen = sizeof (struct sockaddr_in);
286 	}
287 #endif				/* PORTMAP */
288 	xdrs->x_op = XDR_DECODE;
289 	XDR_SETPOS(xdrs, 0);
290 	if (! xdr_callmsg(xdrs, msg)) {
291 		return (FALSE);
292 	}
293 	su->su_xid = msg->rm_xid;
294 	if (su->su_cache != NULL) {
295 		if (cache_get(xprt, msg, &reply, &replylen)) {
296 			(void)_sendto(xprt->xp_fd, reply, replylen, 0,
297 			    (struct sockaddr *)(void *)&ss, alen);
298 			return (FALSE);
299 		}
300 	}
301 	return (TRUE);
302 }
303 
304 static int
305 svc_dg_sendto(int fd, char *buf, int buflen,
306     const struct sockaddr *raddr, socklen_t raddrlen,
307     const struct sockaddr *laddr, socklen_t laddrlen)
308 {
309 	struct msghdr msg;
310 	struct iovec msg_iov[1];
311 	struct sockaddr_in *laddr_in = (struct sockaddr_in *)laddr;
312 	struct in_addr *lin = &laddr_in->sin_addr;
313 	char tmp[CMSG_SPACE(sizeof(*lin))];
314 	struct cmsghdr *cmsg;
315 
316 	memset((char *)&msg, 0, sizeof(msg));
317 	msg_iov[0].iov_base = buf;
318 	msg_iov[0].iov_len = buflen;
319 	msg.msg_iov = msg_iov;
320 	msg.msg_iovlen = 1;
321 	msg.msg_namelen = raddrlen;
322 	msg.msg_name = (char *)raddr;
323 
324 	if (laddr != NULL && laddr->sa_family == AF_INET &&
325 	    lin->s_addr != INADDR_ANY) {
326 		msg.msg_control = (caddr_t)tmp;
327 		msg.msg_controllen = CMSG_LEN(sizeof(*lin));
328 		cmsg = CMSG_FIRSTHDR(&msg);
329 		cmsg->cmsg_len = CMSG_LEN(sizeof(*lin));
330 		cmsg->cmsg_level = IPPROTO_IP;
331 		cmsg->cmsg_type = IP_SENDSRCADDR;
332 		memcpy(CMSG_DATA(cmsg), lin, sizeof(*lin));
333 	}
334 
335 	return _sendmsg(fd, &msg, 0);
336 }
337 
338 static bool_t
339 svc_dg_reply(xprt, msg)
340 	SVCXPRT *xprt;
341 	struct rpc_msg *msg;
342 {
343 	struct svc_dg_data *su = su_data(xprt);
344 	XDR *xdrs = &(su->su_xdrs);
345 	bool_t stat = TRUE;
346 	size_t slen;
347 	xdrproc_t xdr_proc;
348 	caddr_t xdr_where;
349 
350 	xdrs->x_op = XDR_ENCODE;
351 	XDR_SETPOS(xdrs, 0);
352 	msg->rm_xid = su->su_xid;
353 	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
354 	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
355 		xdr_proc = msg->acpted_rply.ar_results.proc;
356 		xdr_where = msg->acpted_rply.ar_results.where;
357 		msg->acpted_rply.ar_results.proc = (xdrproc_t) xdr_void;
358 		msg->acpted_rply.ar_results.where = NULL;
359 
360 		if (!xdr_replymsg(xdrs, msg) ||
361 		    !SVCAUTH_WRAP(&SVC_AUTH(xprt), xdrs, xdr_proc, xdr_where))
362 			stat = FALSE;
363 	} else {
364 		stat = xdr_replymsg(xdrs, msg);
365 	}
366 	if (stat) {
367 		slen = XDR_GETPOS(xdrs);
368 		if (svc_dg_sendto(xprt->xp_fd, rpc_buffer(xprt), slen,
369 		    (struct sockaddr *)xprt->xp_rtaddr.buf,
370 		    (socklen_t)xprt->xp_rtaddr.len,
371 		    (struct sockaddr *)su->su_srcaddr.buf,
372 		    (socklen_t)su->su_srcaddr.len) == (ssize_t) slen) {
373 			stat = TRUE;
374 			if (su->su_cache)
375 				cache_set(xprt, slen);
376 		}
377 	}
378 	return (stat);
379 }
380 
381 static bool_t
382 svc_dg_getargs(xprt, xdr_args, args_ptr)
383 	SVCXPRT *xprt;
384 	xdrproc_t xdr_args;
385 	void *args_ptr;
386 {
387 	struct svc_dg_data *su;
388 
389 	assert(xprt != NULL);
390 	su = su_data(xprt);
391 	return (SVCAUTH_UNWRAP(&SVC_AUTH(xprt),
392 		&su->su_xdrs, xdr_args, args_ptr));
393 }
394 
395 static bool_t
396 svc_dg_freeargs(xprt, xdr_args, args_ptr)
397 	SVCXPRT *xprt;
398 	xdrproc_t xdr_args;
399 	void *args_ptr;
400 {
401 	XDR *xdrs = &(su_data(xprt)->su_xdrs);
402 
403 	xdrs->x_op = XDR_FREE;
404 	return (*xdr_args)(xdrs, args_ptr);
405 }
406 
407 static void
408 svc_dg_destroy(xprt)
409 	SVCXPRT *xprt;
410 {
411 	struct svc_dg_data *su = su_data(xprt);
412 
413 	xprt_unregister(xprt);
414 	if (xprt->xp_fd != -1)
415 		(void)_close(xprt->xp_fd);
416 	XDR_DESTROY(&(su->su_xdrs));
417 	(void) mem_free(rpc_buffer(xprt), su->su_iosz);
418 	if (su->su_srcaddr.buf)
419 		(void) mem_free(su->su_srcaddr.buf, su->su_srcaddr.maxlen);
420 	(void) mem_free(su, sizeof (*su));
421 	if (xprt->xp_rtaddr.buf)
422 		(void) mem_free(xprt->xp_rtaddr.buf, xprt->xp_rtaddr.maxlen);
423 	if (xprt->xp_ltaddr.buf)
424 		(void) mem_free(xprt->xp_ltaddr.buf, xprt->xp_ltaddr.maxlen);
425 	if (xprt->xp_tp)
426 		(void) free(xprt->xp_tp);
427 	svc_xprt_free(xprt);
428 }
429 
430 static bool_t
431 /*ARGSUSED*/
432 svc_dg_control(xprt, rq, in)
433 	SVCXPRT *xprt;
434 	const u_int	rq;
435 	void		*in;
436 {
437 	return (FALSE);
438 }
439 
440 static void
441 svc_dg_ops(xprt)
442 	SVCXPRT *xprt;
443 {
444 	static struct xp_ops ops;
445 	static struct xp_ops2 ops2;
446 
447 /* VARIABLES PROTECTED BY ops_lock: ops */
448 
449 	mutex_lock(&ops_lock);
450 	if (ops.xp_recv == NULL) {
451 		ops.xp_recv = svc_dg_recv;
452 		ops.xp_stat = svc_dg_stat;
453 		ops.xp_getargs = svc_dg_getargs;
454 		ops.xp_reply = svc_dg_reply;
455 		ops.xp_freeargs = svc_dg_freeargs;
456 		ops.xp_destroy = svc_dg_destroy;
457 		ops2.xp_control = svc_dg_control;
458 	}
459 	xprt->xp_ops = &ops;
460 	xprt->xp_ops2 = &ops2;
461 	mutex_unlock(&ops_lock);
462 }
463 
464 /*  The CACHING COMPONENT */
465 
466 /*
467  * Could have been a separate file, but some part of it depends upon the
468  * private structure of the client handle.
469  *
470  * Fifo cache for cl server
471  * Copies pointers to reply buffers into fifo cache
472  * Buffers are sent again if retransmissions are detected.
473  */
474 
475 #define	SPARSENESS 4	/* 75% sparse */
476 
477 #define	ALLOC(type, size)	\
478 	(type *) mem_alloc((sizeof (type) * (size)))
479 
480 #define	MEMZERO(addr, type, size)	 \
481 	(void) memset((void *) (addr), 0, sizeof (type) * (int) (size))
482 
483 #define	FREE(addr, type, size)	\
484 	mem_free((addr), (sizeof (type) * (size)))
485 
486 /*
487  * An entry in the cache
488  */
489 typedef struct cache_node *cache_ptr;
490 struct cache_node {
491 	/*
492 	 * Index into cache is xid, proc, vers, prog and address
493 	 */
494 	u_int32_t cache_xid;
495 	rpcproc_t cache_proc;
496 	rpcvers_t cache_vers;
497 	rpcprog_t cache_prog;
498 	struct netbuf cache_addr;
499 	/*
500 	 * The cached reply and length
501 	 */
502 	char *cache_reply;
503 	size_t cache_replylen;
504 	/*
505 	 * Next node on the list, if there is a collision
506 	 */
507 	cache_ptr cache_next;
508 };
509 
510 /*
511  * The entire cache
512  */
513 struct cl_cache {
514 	u_int uc_size;		/* size of cache */
515 	cache_ptr *uc_entries;	/* hash table of entries in cache */
516 	cache_ptr *uc_fifo;	/* fifo list of entries in cache */
517 	u_int uc_nextvictim;	/* points to next victim in fifo list */
518 	rpcprog_t uc_prog;	/* saved program number */
519 	rpcvers_t uc_vers;	/* saved version number */
520 	rpcproc_t uc_proc;	/* saved procedure number */
521 };
522 
523 
524 /*
525  * the hashing function
526  */
527 #define	CACHE_LOC(transp, xid)	\
528 	(xid % (SPARSENESS * ((struct cl_cache *) \
529 		su_data(transp)->su_cache)->uc_size))
530 
531 /*
532  * Enable use of the cache. Returns 1 on success, 0 on failure.
533  * Note: there is no disable.
534  */
535 static const char cache_enable_str[] = "svc_enablecache: %s %s";
536 static const char alloc_err[] = "could not allocate cache ";
537 static const char enable_err[] = "cache already enabled";
538 
539 int
540 svc_dg_enablecache(transp, size)
541 	SVCXPRT *transp;
542 	u_int size;
543 {
544 	struct svc_dg_data *su = su_data(transp);
545 	struct cl_cache *uc;
546 
547 	mutex_lock(&dupreq_lock);
548 	if (su->su_cache != NULL) {
549 		(void) warnx(cache_enable_str, enable_err, " ");
550 		mutex_unlock(&dupreq_lock);
551 		return (0);
552 	}
553 	uc = ALLOC(struct cl_cache, 1);
554 	if (uc == NULL) {
555 		warnx(cache_enable_str, alloc_err, " ");
556 		mutex_unlock(&dupreq_lock);
557 		return (0);
558 	}
559 	uc->uc_size = size;
560 	uc->uc_nextvictim = 0;
561 	uc->uc_entries = ALLOC(cache_ptr, size * SPARSENESS);
562 	if (uc->uc_entries == NULL) {
563 		warnx(cache_enable_str, alloc_err, "data");
564 		FREE(uc, struct cl_cache, 1);
565 		mutex_unlock(&dupreq_lock);
566 		return (0);
567 	}
568 	MEMZERO(uc->uc_entries, cache_ptr, size * SPARSENESS);
569 	uc->uc_fifo = ALLOC(cache_ptr, size);
570 	if (uc->uc_fifo == NULL) {
571 		warnx(cache_enable_str, alloc_err, "fifo");
572 		FREE(uc->uc_entries, cache_ptr, size * SPARSENESS);
573 		FREE(uc, struct cl_cache, 1);
574 		mutex_unlock(&dupreq_lock);
575 		return (0);
576 	}
577 	MEMZERO(uc->uc_fifo, cache_ptr, size);
578 	su->su_cache = (char *)(void *)uc;
579 	mutex_unlock(&dupreq_lock);
580 	return (1);
581 }
582 
583 /*
584  * Set an entry in the cache.  It assumes that the uc entry is set from
585  * the earlier call to cache_get() for the same procedure.  This will always
586  * happen because cache_get() is calle by svc_dg_recv and cache_set() is called
587  * by svc_dg_reply().  All this hoopla because the right RPC parameters are
588  * not available at svc_dg_reply time.
589  */
590 
591 static const char cache_set_str[] = "cache_set: %s";
592 static const char cache_set_err1[] = "victim not found";
593 static const char cache_set_err2[] = "victim alloc failed";
594 static const char cache_set_err3[] = "could not allocate new rpc buffer";
595 
596 static void
597 cache_set(xprt, replylen)
598 	SVCXPRT *xprt;
599 	size_t replylen;
600 {
601 	cache_ptr victim;
602 	cache_ptr *vicp;
603 	struct svc_dg_data *su = su_data(xprt);
604 	struct cl_cache *uc = (struct cl_cache *) su->su_cache;
605 	u_int loc;
606 	char *newbuf;
607 #ifdef RPC_CACHE_DEBUG
608 	struct netconfig *nconf;
609 	char *uaddr;
610 #endif
611 
612 	mutex_lock(&dupreq_lock);
613 	/*
614 	 * Find space for the new entry, either by
615 	 * reusing an old entry, or by mallocing a new one
616 	 */
617 	victim = uc->uc_fifo[uc->uc_nextvictim];
618 	if (victim != NULL) {
619 		loc = CACHE_LOC(xprt, victim->cache_xid);
620 		for (vicp = &uc->uc_entries[loc];
621 			*vicp != NULL && *vicp != victim;
622 			vicp = &(*vicp)->cache_next)
623 			;
624 		if (*vicp == NULL) {
625 			warnx(cache_set_str, cache_set_err1);
626 			mutex_unlock(&dupreq_lock);
627 			return;
628 		}
629 		*vicp = victim->cache_next;	/* remove from cache */
630 		newbuf = victim->cache_reply;
631 	} else {
632 		victim = ALLOC(struct cache_node, 1);
633 		if (victim == NULL) {
634 			warnx(cache_set_str, cache_set_err2);
635 			mutex_unlock(&dupreq_lock);
636 			return;
637 		}
638 		newbuf = mem_alloc(su->su_iosz);
639 		if (newbuf == NULL) {
640 			warnx(cache_set_str, cache_set_err3);
641 			FREE(victim, struct cache_node, 1);
642 			mutex_unlock(&dupreq_lock);
643 			return;
644 		}
645 	}
646 
647 	/*
648 	 * Store it away
649 	 */
650 #ifdef RPC_CACHE_DEBUG
651 	if (nconf = getnetconfigent(xprt->xp_netid)) {
652 		uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
653 		freenetconfigent(nconf);
654 		printf(
655 	"cache set for xid= %x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
656 			su->su_xid, uc->uc_prog, uc->uc_vers,
657 			uc->uc_proc, uaddr);
658 		free(uaddr);
659 	}
660 #endif
661 	victim->cache_replylen = replylen;
662 	victim->cache_reply = rpc_buffer(xprt);
663 	rpc_buffer(xprt) = newbuf;
664 	xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt),
665 			su->su_iosz, XDR_ENCODE);
666 	victim->cache_xid = su->su_xid;
667 	victim->cache_proc = uc->uc_proc;
668 	victim->cache_vers = uc->uc_vers;
669 	victim->cache_prog = uc->uc_prog;
670 	victim->cache_addr = xprt->xp_rtaddr;
671 	victim->cache_addr.buf = ALLOC(char, xprt->xp_rtaddr.len);
672 	(void) memcpy(victim->cache_addr.buf, xprt->xp_rtaddr.buf,
673 	    (size_t)xprt->xp_rtaddr.len);
674 	loc = CACHE_LOC(xprt, victim->cache_xid);
675 	victim->cache_next = uc->uc_entries[loc];
676 	uc->uc_entries[loc] = victim;
677 	uc->uc_fifo[uc->uc_nextvictim++] = victim;
678 	uc->uc_nextvictim %= uc->uc_size;
679 	mutex_unlock(&dupreq_lock);
680 }
681 
682 /*
683  * Try to get an entry from the cache
684  * return 1 if found, 0 if not found and set the stage for cache_set()
685  */
686 static int
687 cache_get(xprt, msg, replyp, replylenp)
688 	SVCXPRT *xprt;
689 	struct rpc_msg *msg;
690 	char **replyp;
691 	size_t *replylenp;
692 {
693 	u_int loc;
694 	cache_ptr ent;
695 	struct svc_dg_data *su = su_data(xprt);
696 	struct cl_cache *uc = (struct cl_cache *) su->su_cache;
697 #ifdef RPC_CACHE_DEBUG
698 	struct netconfig *nconf;
699 	char *uaddr;
700 #endif
701 
702 	mutex_lock(&dupreq_lock);
703 	loc = CACHE_LOC(xprt, su->su_xid);
704 	for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
705 		if (ent->cache_xid == su->su_xid &&
706 			ent->cache_proc == msg->rm_call.cb_proc &&
707 			ent->cache_vers == msg->rm_call.cb_vers &&
708 			ent->cache_prog == msg->rm_call.cb_prog &&
709 			ent->cache_addr.len == xprt->xp_rtaddr.len &&
710 			(memcmp(ent->cache_addr.buf, xprt->xp_rtaddr.buf,
711 				xprt->xp_rtaddr.len) == 0)) {
712 #ifdef RPC_CACHE_DEBUG
713 			if (nconf = getnetconfigent(xprt->xp_netid)) {
714 				uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
715 				freenetconfigent(nconf);
716 				printf(
717 	"cache entry found for xid=%x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
718 					su->su_xid, msg->rm_call.cb_prog,
719 					msg->rm_call.cb_vers,
720 					msg->rm_call.cb_proc, uaddr);
721 				free(uaddr);
722 			}
723 #endif
724 			*replyp = ent->cache_reply;
725 			*replylenp = ent->cache_replylen;
726 			mutex_unlock(&dupreq_lock);
727 			return (1);
728 		}
729 	}
730 	/*
731 	 * Failed to find entry
732 	 * Remember a few things so we can do a set later
733 	 */
734 	uc->uc_proc = msg->rm_call.cb_proc;
735 	uc->uc_vers = msg->rm_call.cb_vers;
736 	uc->uc_prog = msg->rm_call.cb_prog;
737 	mutex_unlock(&dupreq_lock);
738 	return (0);
739 }
740