xref: /illumos-gate/usr/src/lib/libnsl/rpc/svc_dg.c (revision 09b0d01c5bc323b8ee7043100e09aded27cc12ab)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2014 Gary Mills
24  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
25  * Use is subject to license terms.
26  */
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 /*
30  * Portions of this source code were derived from Berkeley
31  * 4.3 BSD under license from the Regents of the University of
32  * California.
33  */
34 
35 /*
36  * svc_dg.c, Server side for connectionless RPC.
37  *
38  * Does some caching in the hopes of achieving execute-at-most-once semantics.
39  */
40 
41 #include "mt.h"
42 #include "rpc_mt.h"
43 #include <stdio.h>
44 #include <sys/types.h>
45 #include <sys/sysmacros.h>
46 #include <rpc/rpc.h>
47 #include <rpcsvc/svc_dg_priv.h>
48 #include <errno.h>
49 #include <syslog.h>
50 #include <stdlib.h>
51 #include <string.h>
52 #include <ucred.h>
53 #include <unistd.h>
54 #include <sys/socket.h>
55 #include <netinet/in.h>
56 #include <arpa/inet.h>
57 #ifdef RPC_CACHE_DEBUG
58 #include <netconfig.h>
59 #include <netdir.h>
60 #endif
61 
62 #ifndef MAX
63 #define	MAX(a, b)	(((a) > (b)) ? (a) : (b))
64 #endif
65 
66 static struct xp_ops *svc_dg_ops();
67 static void cache_set();
68 static int cache_get();
69 
70 #define	rpc_buffer(xprt) ((xprt)->xp_p1)
71 
72 /*
73  * Usage:
74  *	xprt = svc_dg_create(sock, sendsize, recvsize);
75  * Does other connectionless specific initializations.
76  * Once *xprt is initialized, it is registered.
77  * see (svc.h, xprt_register). If recvsize or sendsize are 0 suitable
78  * system defaults are chosen.
79  * The routines returns NULL if a problem occurred.
80  */
81 static const char svc_dg_str[] = "svc_dg_create: %s";
82 static const char svc_dg_err1[] = "could not get transport information";
83 static const char svc_dg_err2[] = " transport does not support data transfer";
84 static const char svc_dg_err3[] =
85 		"fd > FD_SETSIZE; Use rpc_control(RPC_SVC_USE_POLLFD,...);";
86 static const char __no_mem_str[] = "out of memory";
87 
88 /* Structure used to initialize SVC_XP_AUTH(xprt).svc_ah_ops. */
89 extern struct svc_auth_ops svc_auth_any_ops;
90 extern int __rpc_get_ltaddr(struct netbuf *, struct netbuf *);
91 
92 void
svc_dg_xprtfree(SVCXPRT * xprt)93 svc_dg_xprtfree(SVCXPRT *xprt)
94 {
95 /* LINTED pointer alignment */
96 	SVCXPRT_EXT		*xt = xprt ? SVCEXT(xprt) : NULL;
97 /* LINTED pointer alignment */
98 	struct svc_dg_data	*su = xprt ? get_svc_dg_data(xprt) : NULL;
99 
100 	if (xprt == NULL)
101 		return;
102 	if (xprt->xp_netid)
103 		free(xprt->xp_netid);
104 	if (xprt->xp_tp)
105 		free(xprt->xp_tp);
106 	if (xt->parent == NULL)
107 		if (xprt->xp_ltaddr.buf)
108 			free(xprt->xp_ltaddr.buf);
109 	if (xprt->xp_rtaddr.buf)
110 		free(xprt->xp_rtaddr.buf);
111 	if (su != NULL) {
112 		XDR_DESTROY(&(su->su_xdrs));
113 		free(su);
114 	}
115 	if (rpc_buffer(xprt))
116 		free(rpc_buffer(xprt));
117 	svc_xprt_free(xprt);
118 }
119 
120 SVCXPRT *
svc_dg_create_private(int fd,uint_t sendsize,uint_t recvsize)121 svc_dg_create_private(int fd, uint_t sendsize, uint_t recvsize)
122 {
123 	SVCXPRT *xprt;
124 	struct svc_dg_data *su = NULL;
125 	struct t_info tinfo;
126 	size_t ucred_sz = ucred_size();
127 
128 	if (RPC_FD_NOTIN_FDSET(fd)) {
129 		errno = EBADF;
130 		t_errno = TBADF;
131 		syslog(LOG_ERR, svc_dg_str, svc_dg_err3);
132 		return (NULL);
133 	}
134 
135 	if (t_getinfo(fd, &tinfo) == -1) {
136 		syslog(LOG_ERR, svc_dg_str, svc_dg_err1);
137 		return (NULL);
138 	}
139 	/*
140 	 * Find the receive and the send size
141 	 */
142 	sendsize = __rpc_get_t_size((int)sendsize, tinfo.tsdu);
143 	recvsize = __rpc_get_t_size((int)recvsize, tinfo.tsdu);
144 	if ((sendsize == 0) || (recvsize == 0)) {
145 		syslog(LOG_ERR, svc_dg_str, svc_dg_err2);
146 		return (NULL);
147 	}
148 
149 	if ((xprt = svc_xprt_alloc()) == NULL)
150 		goto freedata;
151 /* LINTED pointer alignment */
152 	svc_flags(xprt) |= SVC_DGRAM;
153 
154 	su = malloc(sizeof (*su) + ucred_sz);
155 	if (su == NULL)
156 		goto freedata;
157 	su->su_iosz = ((MAX(sendsize, recvsize) + 3) / 4) * 4;
158 	if ((rpc_buffer(xprt) = malloc(su->su_iosz)) == NULL)
159 		goto freedata;
160 	xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
161 	    XDR_DECODE);
162 	su->su_cache = NULL;
163 	xprt->xp_fd = fd;
164 	xprt->xp_p2 = (caddr_t)su;
165 	xprt->xp_verf.oa_base = su->su_verfbody;
166 	xprt->xp_ops = svc_dg_ops();
167 
168 	su->su_tudata.addr.maxlen =  0; /* Fill in later */
169 
170 	su->su_tudata.udata.buf = (char *)rpc_buffer(xprt);
171 	su->su_tudata.opt.buf = (char *)su->opts;
172 	su->su_tudata.udata.maxlen = su->su_iosz;
173 	su->su_tudata.opt.maxlen = MAX_OPT_WORDS * sizeof (int) + ucred_sz;
174 /* LINTED pointer alignment */
175 	SVC_XP_AUTH(xprt).svc_ah_ops = svc_auth_any_ops;
176 /* LINTED pointer alignment */
177 	SVC_XP_AUTH(xprt).svc_ah_private = NULL;
178 	return (xprt);
179 freedata:
180 	(void) syslog(LOG_ERR, svc_dg_str, __no_mem_str);
181 	if (xprt)
182 		svc_dg_xprtfree(xprt);
183 	return (NULL);
184 }
185 
186 SVCXPRT *
svc_dg_create(const int fd,const uint_t sendsize,const uint_t recvsize)187 svc_dg_create(const int fd, const uint_t sendsize, const uint_t recvsize)
188 {
189 	SVCXPRT *xprt;
190 
191 	if ((xprt = svc_dg_create_private(fd, sendsize, recvsize)) != NULL)
192 		xprt_register(xprt);
193 	return (xprt);
194 }
195 
196 SVCXPRT *
svc_dg_xprtcopy(SVCXPRT * parent)197 svc_dg_xprtcopy(SVCXPRT *parent)
198 {
199 	SVCXPRT			*xprt;
200 	struct svc_dg_data	*su;
201 	size_t			ucred_sz = ucred_size();
202 
203 	if ((xprt = svc_xprt_alloc()) == NULL)
204 		return (NULL);
205 
206 /* LINTED pointer alignment */
207 	SVCEXT(xprt)->parent = parent;
208 /* LINTED pointer alignment */
209 	SVCEXT(xprt)->flags = SVCEXT(parent)->flags;
210 
211 	xprt->xp_fd = parent->xp_fd;
212 	xprt->xp_port = parent->xp_port;
213 	xprt->xp_ops = svc_dg_ops();
214 	if (parent->xp_tp) {
215 		xprt->xp_tp = (char *)strdup(parent->xp_tp);
216 		if (xprt->xp_tp == NULL) {
217 			syslog(LOG_ERR, "svc_dg_xprtcopy: strdup failed");
218 			svc_dg_xprtfree(xprt);
219 			return (NULL);
220 		}
221 	}
222 	if (parent->xp_netid) {
223 		xprt->xp_netid = (char *)strdup(parent->xp_netid);
224 		if (xprt->xp_netid == NULL) {
225 			syslog(LOG_ERR, "svc_dg_xprtcopy: strdup failed");
226 			if (parent->xp_tp)
227 				free(parent->xp_tp);
228 			svc_dg_xprtfree(xprt);
229 			return (NULL);
230 		}
231 	}
232 	xprt->xp_ltaddr = parent->xp_ltaddr;	/* shared with parent */
233 
234 	xprt->xp_rtaddr = parent->xp_rtaddr;
235 	xprt->xp_rtaddr.buf = malloc(xprt->xp_rtaddr.maxlen);
236 	if (xprt->xp_rtaddr.buf == NULL) {
237 		svc_dg_xprtfree(xprt);
238 		return (NULL);
239 	}
240 	(void) memcpy(xprt->xp_rtaddr.buf, parent->xp_rtaddr.buf,
241 	    xprt->xp_rtaddr.maxlen);
242 	xprt->xp_type = parent->xp_type;
243 
244 	if ((su = malloc(sizeof (struct svc_dg_data) + ucred_sz)) == NULL) {
245 		svc_dg_xprtfree(xprt);
246 		return (NULL);
247 	}
248 /* LINTED pointer alignment */
249 	su->su_iosz = get_svc_dg_data(parent)->su_iosz;
250 	if ((rpc_buffer(xprt) = malloc(su->su_iosz)) == NULL) {
251 		svc_dg_xprtfree(xprt);
252 		free(su);
253 		return (NULL);
254 	}
255 	xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
256 	    XDR_DECODE);
257 	su->su_cache = NULL;
258 	su->su_tudata.addr.maxlen =  0; /* Fill in later */
259 	su->su_tudata.udata.buf = (char *)rpc_buffer(xprt);
260 	su->su_tudata.opt.buf = (char *)su->opts;
261 	su->su_tudata.udata.maxlen = su->su_iosz;
262 	su->su_tudata.opt.maxlen = MAX_OPT_WORDS * sizeof (int) + ucred_sz;
263 	xprt->xp_p2 = (caddr_t)su;	/* get_svc_dg_data(xprt) = su */
264 	xprt->xp_verf.oa_base = su->su_verfbody;
265 
266 	return (xprt);
267 }
268 
269 /*ARGSUSED*/
270 static enum xprt_stat
svc_dg_stat(SVCXPRT * xprt)271 svc_dg_stat(SVCXPRT *xprt)
272 {
273 	return (XPRT_IDLE);
274 }
275 
276 /*
277  * Find the SCM_UCRED in src and place a pointer to that option alone in dest.
278  * Note that these two 'netbuf' structures might be the same one, so the code
279  * has to be careful about referring to src after changing dest.
280  */
281 static void
extract_cred(const struct netbuf * src,struct netbuf * dest)282 extract_cred(const struct netbuf *src, struct netbuf *dest)
283 {
284 	char *cp = src->buf;
285 	unsigned int len = src->len;
286 	const struct T_opthdr *opt;
287 	unsigned int olen;
288 
289 	while (len >= sizeof (*opt)) {
290 		/* LINTED: pointer alignment */
291 		opt = (const struct T_opthdr *)cp;
292 		olen = opt->len;
293 		if (olen > len || olen < sizeof (*opt) ||
294 		    !IS_P2ALIGNED(olen, sizeof (t_uscalar_t)))
295 			break;
296 		if (opt->level == SOL_SOCKET && opt->name == SCM_UCRED) {
297 			dest->buf = cp;
298 			dest->len = olen;
299 			return;
300 		}
301 		cp += olen;
302 		len -= olen;
303 	}
304 	dest->len = 0;
305 }
306 
307 /*
308  * This routine extracts the destination IP address of the inbound RPC packet
309  * and sets that as source IP address for the outbound response.
310  */
311 static void
set_src_addr(SVCXPRT * xprt,struct netbuf * opt)312 set_src_addr(SVCXPRT *xprt, struct netbuf *opt)
313 {
314 	struct netbuf *nbufp, *ltaddr;
315 	struct T_opthdr *opthdr;
316 	in_pktinfo_t *pktinfo;
317 	struct sockaddr_in *sock = (struct sockaddr_in *)NULL;
318 
319 	/* extract dest IP of inbound packet */
320 	/* LINTED pointer alignment */
321 	nbufp = (struct netbuf *)xprt->xp_p2;
322 	ltaddr = &xprt->xp_ltaddr;
323 	if (__rpc_get_ltaddr(nbufp, ltaddr) != 0)
324 		return;
325 
326 	/* do nothing for non-IPv4 packet */
327 	/* LINTED pointer alignment */
328 	sock = (struct sockaddr_in *)ltaddr->buf;
329 	if (sock->sin_family != AF_INET)
330 		return;
331 
332 	/* set desired option header */
333 	opthdr = (struct T_opthdr *)memalign(sizeof (int),
334 	    sizeof (struct T_opthdr) + sizeof (in_pktinfo_t));
335 	if (opthdr == NULL)
336 		return;
337 	opthdr->len = sizeof (struct T_opthdr) + sizeof (in_pktinfo_t);
338 	opthdr->level = IPPROTO_IP;
339 	opthdr->name = IP_PKTINFO;
340 
341 	/*
342 	 * 1. set source IP of outbound packet
343 	 * 2. value '0' for index means IP layer uses this as source address
344 	 */
345 	pktinfo = (in_pktinfo_t *)(opthdr + 1);
346 	(void) memset(pktinfo, 0, sizeof (in_pktinfo_t));
347 	pktinfo->ipi_spec_dst.s_addr = sock->sin_addr.s_addr;
348 	pktinfo->ipi_ifindex = 0;
349 
350 	/* copy data into ancillary buffer */
351 	if (opthdr->len + opt->len <= opt->maxlen) {
352 		(void) memcpy((void *)(opt->buf+opt->len), (const void *)opthdr,
353 		    opthdr->len);
354 		opt->len += opthdr->len;
355 	}
356 	free(opthdr);
357 }
358 
359 static bool_t
svc_dg_recv(SVCXPRT * xprt,struct rpc_msg * msg)360 svc_dg_recv(SVCXPRT *xprt, struct rpc_msg *msg)
361 {
362 /* LINTED pointer alignment */
363 	struct svc_dg_data *su = get_svc_dg_data(xprt);
364 	XDR *xdrs = &(su->su_xdrs);
365 	struct t_unitdata *tu_data = &(su->su_tudata);
366 	int moreflag;
367 	struct netbuf *nbufp;
368 	struct netconfig *nconf;
369 
370 	/* XXX: tudata should have been made a part of the server handle */
371 	if (tu_data->addr.maxlen == 0)
372 		tu_data->addr = xprt->xp_rtaddr;
373 again:
374 	tu_data->addr.len = 0;
375 	tu_data->opt.len  = 0;
376 	tu_data->udata.len  = 0;
377 
378 	moreflag = 0;
379 	if (t_rcvudata(xprt->xp_fd, tu_data, &moreflag) == -1) {
380 #ifdef RPC_DEBUG
381 		syslog(LOG_ERR, "svc_dg_recv: t_rcvudata t_errno=%d errno=%d\n",
382 		    t_errno, errno);
383 #endif
384 		if (t_errno == TLOOK) {
385 			int lookres;
386 
387 			lookres = t_look(xprt->xp_fd);
388 			if ((lookres == T_UDERR) &&
389 			    (t_rcvuderr(xprt->xp_fd,
390 				    (struct t_uderr *)0) < 0)) {
391 				/*EMPTY*/
392 #ifdef RPC_DEBUG
393 				syslog(LOG_ERR,
394 				"svc_dg_recv: t_rcvuderr t_errno = %d\n",
395 					t_errno);
396 #endif
397 			}
398 			if (lookres == T_DATA)
399 				goto again;
400 		} else if ((errno == EINTR) && (t_errno == TSYSERR))
401 			goto again;
402 		else {
403 			return (FALSE);
404 		}
405 	}
406 
407 	if ((moreflag) ||
408 	    (tu_data->udata.len < 4 * (uint_t)sizeof (uint32_t))) {
409 		/*
410 		 * If moreflag is set, drop that data packet. Something wrong
411 		 */
412 		return (FALSE);
413 	}
414 	su->optbuf = tu_data->opt;
415 	xprt->xp_rtaddr.len = tu_data->addr.len;
416 	xdrs->x_op = XDR_DECODE;
417 	XDR_SETPOS(xdrs, 0);
418 	if (!xdr_callmsg(xdrs, msg))
419 		return (FALSE);
420 	su->su_xid = msg->rm_xid;
421 	if (su->su_cache != NULL) {
422 		char *reply;
423 		uint32_t replylen;
424 
425 		if (cache_get(xprt, msg, &reply, &replylen)) {
426 			/* tu_data.addr is already set */
427 			tu_data->udata.buf = reply;
428 			tu_data->udata.len = (uint_t)replylen;
429 			extract_cred(&tu_data->opt, &tu_data->opt);
430 			set_src_addr(xprt, &tu_data->opt);
431 			(void) t_sndudata(xprt->xp_fd, tu_data);
432 			tu_data->udata.buf = (char *)rpc_buffer(xprt);
433 			tu_data->opt.buf = (char *)su->opts;
434 			return (FALSE);
435 		}
436 	}
437 
438 	/*
439 	 * get local ip address
440 	 */
441 
442 	if ((nconf = getnetconfigent(xprt->xp_netid)) != NULL) {
443 		if (strcmp(nconf->nc_protofmly, NC_INET) == 0 ||
444 		    strcmp(nconf->nc_protofmly, NC_INET6) == 0) {
445 			if (nconf->nc_semantics == NC_TPI_CLTS) {
446 				/* LINTED pointer cast */
447 				nbufp = (struct netbuf *)(xprt->xp_p2);
448 				if (__rpc_get_ltaddr(nbufp,
449 				    &xprt->xp_ltaddr) < 0) {
450 					if (strcmp(nconf->nc_protofmly,
451 					    NC_INET) == 0) {
452 						syslog(LOG_ERR,
453 						    "svc_dg_recv: ip(udp), "
454 						    "t_errno=%d, errno=%d",
455 						    t_errno, errno);
456 					}
457 					if (strcmp(nconf->nc_protofmly,
458 					    NC_INET6) == 0) {
459 						syslog(LOG_ERR,
460 						    "svc_dg_recv: ip (udp6), "
461 						    "t_errno=%d, errno=%d",
462 						    t_errno, errno);
463 					}
464 					freenetconfigent(nconf);
465 					return (FALSE);
466 				}
467 			}
468 		}
469 		freenetconfigent(nconf);
470 	}
471 	return (TRUE);
472 }
473 
474 static bool_t
svc_dg_reply(SVCXPRT * xprt,struct rpc_msg * msg)475 svc_dg_reply(SVCXPRT *xprt, struct rpc_msg *msg)
476 {
477 /* LINTED pointer alignment */
478 	struct svc_dg_data *su = get_svc_dg_data(xprt);
479 	XDR *xdrs = &(su->su_xdrs);
480 	bool_t stat = FALSE;
481 	xdrproc_t xdr_results;
482 	caddr_t xdr_location;
483 	bool_t has_args;
484 
485 	if (msg->rm_reply.rp_stat == MSG_ACCEPTED &&
486 	    msg->rm_reply.rp_acpt.ar_stat == SUCCESS) {
487 		has_args = TRUE;
488 		xdr_results = msg->acpted_rply.ar_results.proc;
489 		xdr_location = msg->acpted_rply.ar_results.where;
490 		msg->acpted_rply.ar_results.proc = xdr_void;
491 		msg->acpted_rply.ar_results.where = NULL;
492 	} else
493 		has_args = FALSE;
494 
495 	xdrs->x_op = XDR_ENCODE;
496 	XDR_SETPOS(xdrs, 0);
497 	msg->rm_xid = su->su_xid;
498 	if (xdr_replymsg(xdrs, msg) && (!has_args ||
499 /* LINTED pointer alignment */
500 	    SVCAUTH_WRAP(&SVC_XP_AUTH(xprt), xdrs, xdr_results,
501 	    xdr_location))) {
502 		int slen;
503 		struct t_unitdata *tu_data = &(su->su_tudata);
504 
505 		slen = (int)XDR_GETPOS(xdrs);
506 		tu_data->udata.len = slen;
507 		extract_cred(&su->optbuf, &tu_data->opt);
508 		set_src_addr(xprt, &tu_data->opt);
509 try_again:
510 		if (t_sndudata(xprt->xp_fd, tu_data) == 0) {
511 			stat = TRUE;
512 			if (su->su_cache && slen >= 0) {
513 				cache_set(xprt, (uint32_t)slen);
514 			}
515 		} else {
516 			if (errno == EINTR)
517 				goto try_again;
518 
519 			syslog(LOG_ERR,
520 			    "svc_dg_reply: t_sndudata error t_errno=%d ",
521 			    "errno=%d\n", t_errno, errno);
522 		}
523 		tu_data->opt.buf = (char *)su->opts;
524 	}
525 	return (stat);
526 }
527 
528 static bool_t
svc_dg_getargs(SVCXPRT * xprt,xdrproc_t xdr_args,caddr_t args_ptr)529 svc_dg_getargs(SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
530 {
531 	if (svc_mt_mode != RPC_SVC_MT_NONE)
532 		svc_args_done(xprt);
533 /* LINTED pointer alignment */
534 	return (SVCAUTH_UNWRAP(&SVC_XP_AUTH(xprt),
535 	    &(get_svc_dg_data(xprt)->su_xdrs), xdr_args, args_ptr));
536 }
537 
538 static bool_t
svc_dg_freeargs(SVCXPRT * xprt,xdrproc_t xdr_args,caddr_t args_ptr)539 svc_dg_freeargs(SVCXPRT *xprt, xdrproc_t xdr_args, caddr_t args_ptr)
540 {
541 /* LINTED pointer alignment */
542 	XDR *xdrs = &(get_svc_dg_data(xprt)->su_xdrs);
543 
544 	xdrs->x_op = XDR_FREE;
545 	return ((*xdr_args)(xdrs, args_ptr));
546 }
547 
548 static void
svc_dg_destroy(SVCXPRT * xprt)549 svc_dg_destroy(SVCXPRT *xprt)
550 {
551 	(void) mutex_lock(&svc_mutex);
552 	_svc_dg_destroy_private(xprt);
553 	(void) mutex_unlock(&svc_mutex);
554 }
555 
556 void
_svc_dg_destroy_private(SVCXPRT * xprt)557 _svc_dg_destroy_private(SVCXPRT *xprt)
558 {
559 	if (svc_mt_mode != RPC_SVC_MT_NONE) {
560 /* LINTED pointer alignment */
561 		if (SVCEXT(xprt)->parent)
562 /* LINTED pointer alignment */
563 			xprt = SVCEXT(xprt)->parent;
564 /* LINTED pointer alignment */
565 		svc_flags(xprt) |= SVC_DEFUNCT;
566 /* LINTED pointer alignment */
567 		if (SVCEXT(xprt)->refcnt > 0)
568 			return;
569 	}
570 
571 	xprt_unregister(xprt);
572 	(void) t_close(xprt->xp_fd);
573 
574 	if (svc_mt_mode != RPC_SVC_MT_NONE)
575 		svc_xprt_destroy(xprt);
576 	else
577 		svc_dg_xprtfree(xprt);
578 }
579 
580 /*ARGSUSED*/
581 static bool_t
svc_dg_control(SVCXPRT * xprt,const uint_t rq,void * in)582 svc_dg_control(SVCXPRT *xprt, const uint_t rq, void *in)
583 {
584 	switch (rq) {
585 	case SVCGET_XID:
586 		if (xprt->xp_p2 == NULL)
587 			return (FALSE);
588 		/* LINTED pointer alignment */
589 		*(uint32_t *)in = ((struct svc_dg_data *)(xprt->xp_p2))->su_xid;
590 		return (TRUE);
591 	default:
592 		return (FALSE);
593 	}
594 }
595 
596 static struct xp_ops *
svc_dg_ops(void)597 svc_dg_ops(void)
598 {
599 	static struct xp_ops ops;
600 	extern mutex_t ops_lock;
601 
602 /* VARIABLES PROTECTED BY ops_lock: ops */
603 
604 	(void) mutex_lock(&ops_lock);
605 	if (ops.xp_recv == NULL) {
606 		ops.xp_recv = svc_dg_recv;
607 		ops.xp_stat = svc_dg_stat;
608 		ops.xp_getargs = svc_dg_getargs;
609 		ops.xp_reply = svc_dg_reply;
610 		ops.xp_freeargs = svc_dg_freeargs;
611 		ops.xp_destroy = svc_dg_destroy;
612 		ops.xp_control = svc_dg_control;
613 	}
614 	(void) mutex_unlock(&ops_lock);
615 	return (&ops);
616 }
617 
618 /*  The CACHING COMPONENT */
619 
620 /*
621  * Could have been a separate file, but some part of it depends upon the
622  * private structure of the client handle.
623  *
624  * Fifo cache for cl server
625  * Copies pointers to reply buffers into fifo cache
626  * Buffers are sent again if retransmissions are detected.
627  */
628 
629 #define	SPARSENESS 4	/* 75% sparse */
630 
631 /*
632  * An entry in the cache
633  */
634 typedef struct cache_node *cache_ptr;
635 struct cache_node {
636 	/*
637 	 * Index into cache is xid, proc, vers, prog and address
638 	 */
639 	uint32_t cache_xid;
640 	rpcproc_t cache_proc;
641 	rpcvers_t cache_vers;
642 	rpcprog_t cache_prog;
643 	struct netbuf cache_addr;
644 	/*
645 	 * The cached reply and length
646 	 */
647 	char *cache_reply;
648 	uint32_t cache_replylen;
649 	/*
650 	 * Next node on the list, if there is a collision
651 	 */
652 	cache_ptr cache_next;
653 };
654 
655 /*
656  * The entire cache
657  */
658 struct cl_cache {
659 	uint32_t uc_size;		/* size of cache */
660 	cache_ptr *uc_entries;	/* hash table of entries in cache */
661 	cache_ptr *uc_fifo;	/* fifo list of entries in cache */
662 	uint32_t uc_nextvictim;	/* points to next victim in fifo list */
663 	rpcprog_t uc_prog;	/* saved program number */
664 	rpcvers_t uc_vers;	/* saved version number */
665 	rpcproc_t uc_proc;	/* saved procedure number */
666 };
667 
668 
669 /*
670  * the hashing function
671  */
672 #define	CACHE_LOC(transp, xid)	\
673 	(xid % (SPARSENESS * ((struct cl_cache *) \
674 		get_svc_dg_data(transp)->su_cache)->uc_size))
675 
676 extern mutex_t	dupreq_lock;
677 
678 /*
679  * Enable use of the cache. Returns 1 on success, 0 on failure.
680  * Note: there is no disable.
681  */
682 static const char cache_enable_str[] = "svc_enablecache: %s %s";
683 static const char alloc_err[] = "could not allocate cache ";
684 static const char enable_err[] = "cache already enabled";
685 
686 int
svc_dg_enablecache(SVCXPRT * xprt,const uint_t size)687 svc_dg_enablecache(SVCXPRT *xprt, const uint_t size)
688 {
689 	SVCXPRT *transp;
690 	struct svc_dg_data *su;
691 	struct cl_cache *uc;
692 
693 /* LINTED pointer alignment */
694 	if (svc_mt_mode != RPC_SVC_MT_NONE && SVCEXT(xprt)->parent != NULL)
695 /* LINTED pointer alignment */
696 		transp = SVCEXT(xprt)->parent;
697 	else
698 		transp = xprt;
699 /* LINTED pointer alignment */
700 	su = get_svc_dg_data(transp);
701 
702 	(void) mutex_lock(&dupreq_lock);
703 	if (su->su_cache != NULL) {
704 		(void) syslog(LOG_ERR, cache_enable_str,
705 		    enable_err, " ");
706 		(void) mutex_unlock(&dupreq_lock);
707 		return (0);
708 	}
709 	uc = malloc(sizeof (struct cl_cache));
710 	if (uc == NULL) {
711 		(void) syslog(LOG_ERR, cache_enable_str,
712 		    alloc_err, " ");
713 		(void) mutex_unlock(&dupreq_lock);
714 		return (0);
715 	}
716 	uc->uc_size = size;
717 	uc->uc_nextvictim = 0;
718 	uc->uc_entries = calloc(size * SPARSENESS, sizeof (cache_ptr));
719 	if (uc->uc_entries == NULL) {
720 		(void) syslog(LOG_ERR, cache_enable_str, alloc_err, "data");
721 		free(uc);
722 		(void) mutex_unlock(&dupreq_lock);
723 		return (0);
724 	}
725 	uc->uc_fifo = calloc(size, sizeof (cache_ptr));
726 	if (uc->uc_fifo == NULL) {
727 		(void) syslog(LOG_ERR, cache_enable_str, alloc_err, "fifo");
728 		free(uc->uc_entries);
729 		free(uc);
730 		(void) mutex_unlock(&dupreq_lock);
731 		return (0);
732 	}
733 	su->su_cache = (char *)uc;
734 	(void) mutex_unlock(&dupreq_lock);
735 	return (1);
736 }
737 
738 /*
739  * Set an entry in the cache.  It assumes that the uc entry is set from
740  * the earlier call to cache_get() for the same procedure.  This will always
741  * happen because cache_get() is calle by svc_dg_recv and cache_set() is called
742  * by svc_dg_reply().  All this hoopla because the right RPC parameters are
743  * not available at svc_dg_reply time.
744  */
745 
746 static const char cache_set_str[] = "cache_set: %s";
747 static const char cache_set_err1[] = "victim not found";
748 static const char cache_set_err2[] = "victim alloc failed";
749 static const char cache_set_err3[] = "could not allocate new rpc buffer";
750 
751 static void
cache_set(SVCXPRT * xprt,uint32_t replylen)752 cache_set(SVCXPRT *xprt, uint32_t replylen)
753 {
754 	SVCXPRT *parent;
755 	cache_ptr victim;
756 	cache_ptr *vicp;
757 	struct svc_dg_data *su;
758 	struct cl_cache *uc;
759 	uint_t loc;
760 	char *newbuf, *newbuf2;
761 	int my_mallocs = 0;
762 #ifdef RPC_CACHE_DEBUG
763 	struct netconfig *nconf;
764 	char *uaddr;
765 #endif
766 
767 /* LINTED pointer alignment */
768 	if (svc_mt_mode != RPC_SVC_MT_NONE && SVCEXT(xprt)->parent != NULL)
769 /* LINTED pointer alignment */
770 		parent = SVCEXT(xprt)->parent;
771 	else
772 		parent = xprt;
773 /* LINTED pointer alignment */
774 	su = get_svc_dg_data(xprt);
775 /* LINTED pointer alignment */
776 	uc = (struct cl_cache *)get_svc_dg_data(parent)->su_cache;
777 
778 	(void) mutex_lock(&dupreq_lock);
779 	/*
780 	 * Find space for the new entry, either by
781 	 * reusing an old entry, or by mallocing a new one
782 	 */
783 	victim = uc->uc_fifo[uc->uc_nextvictim];
784 	if (victim != NULL) {
785 /* LINTED pointer alignment */
786 		loc = CACHE_LOC(parent, victim->cache_xid);
787 		for (vicp = &uc->uc_entries[loc];
788 		    *vicp != NULL && *vicp != victim;
789 		    vicp = &(*vicp)->cache_next)
790 			;
791 		if (*vicp == NULL) {
792 			(void) syslog(LOG_ERR, cache_set_str, cache_set_err1);
793 			(void) mutex_unlock(&dupreq_lock);
794 			return;
795 		}
796 		*vicp = victim->cache_next;	/* remove from cache */
797 		newbuf = victim->cache_reply;
798 	} else {
799 		victim = malloc(sizeof (struct cache_node));
800 		if (victim == NULL) {
801 			(void) syslog(LOG_ERR, cache_set_str, cache_set_err2);
802 			(void) mutex_unlock(&dupreq_lock);
803 			return;
804 		}
805 		newbuf = malloc(su->su_iosz);
806 		if (newbuf == NULL) {
807 			(void) syslog(LOG_ERR, cache_set_str, cache_set_err3);
808 			free(victim);
809 			(void) mutex_unlock(&dupreq_lock);
810 			return;
811 		}
812 		my_mallocs = 1;
813 	}
814 
815 	/*
816 	 * Store it away
817 	 */
818 #ifdef RPC_CACHE_DEBUG
819 	if (nconf = getnetconfigent(xprt->xp_netid)) {
820 		uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
821 		freenetconfigent(nconf);
822 		printf(
823 	"cache set for xid= %x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
824 		    su->su_xid, uc->uc_prog, uc->uc_vers, uc->uc_proc, uaddr);
825 		free(uaddr);
826 	}
827 #endif
828 	newbuf2 = malloc(sizeof (char) * xprt->xp_rtaddr.len);
829 	if (newbuf2 == NULL) {
830 		syslog(LOG_ERR, "cache_set : out of memory");
831 		if (my_mallocs) {
832 			free(victim);
833 			free(newbuf);
834 		}
835 		(void) mutex_unlock(&dupreq_lock);
836 		return;
837 	}
838 	victim->cache_replylen = replylen;
839 	victim->cache_reply = rpc_buffer(xprt);
840 	rpc_buffer(xprt) = newbuf;
841 	xdrmem_create(&(su->su_xdrs), rpc_buffer(xprt), su->su_iosz,
842 	    XDR_ENCODE);
843 	su->su_tudata.udata.buf = (char *)rpc_buffer(xprt);
844 	victim->cache_xid = su->su_xid;
845 	victim->cache_proc = uc->uc_proc;
846 	victim->cache_vers = uc->uc_vers;
847 	victim->cache_prog = uc->uc_prog;
848 	victim->cache_addr = xprt->xp_rtaddr;
849 	victim->cache_addr.buf = newbuf2;
850 	(void) memcpy(victim->cache_addr.buf, xprt->xp_rtaddr.buf,
851 	    (int)xprt->xp_rtaddr.len);
852 /* LINTED pointer alignment */
853 	loc = CACHE_LOC(parent, victim->cache_xid);
854 	victim->cache_next = uc->uc_entries[loc];
855 	uc->uc_entries[loc] = victim;
856 	uc->uc_fifo[uc->uc_nextvictim++] = victim;
857 	uc->uc_nextvictim %= uc->uc_size;
858 	(void) mutex_unlock(&dupreq_lock);
859 }
860 
861 /*
862  * Try to get an entry from the cache
863  * return 1 if found, 0 if not found and set the stage for cache_set()
864  */
865 static int
cache_get(SVCXPRT * xprt,struct rpc_msg * msg,char ** replyp,uint32_t * replylenp)866 cache_get(SVCXPRT *xprt, struct rpc_msg *msg, char **replyp,
867 							uint32_t *replylenp)
868 {
869 	SVCXPRT *parent;
870 	uint_t loc;
871 	cache_ptr ent;
872 	struct svc_dg_data *su;
873 	struct cl_cache *uc;
874 #ifdef RPC_CACHE_DEBUG
875 	struct netconfig *nconf;
876 	char *uaddr;
877 #endif
878 
879 /* LINTED pointer alignment */
880 	if (svc_mt_mode != RPC_SVC_MT_NONE && SVCEXT(xprt)->parent != NULL)
881 /* LINTED pointer alignment */
882 		parent = SVCEXT(xprt)->parent;
883 	else
884 		parent = xprt;
885 /* LINTED pointer alignment */
886 	su = get_svc_dg_data(xprt);
887 /* LINTED pointer alignment */
888 	uc = (struct cl_cache *)get_svc_dg_data(parent)->su_cache;
889 
890 	(void) mutex_lock(&dupreq_lock);
891 /* LINTED pointer alignment */
892 	loc = CACHE_LOC(parent, su->su_xid);
893 	for (ent = uc->uc_entries[loc]; ent != NULL; ent = ent->cache_next) {
894 		if (ent->cache_xid == su->su_xid &&
895 		    ent->cache_proc == msg->rm_call.cb_proc &&
896 		    ent->cache_vers == msg->rm_call.cb_vers &&
897 		    ent->cache_prog == msg->rm_call.cb_prog &&
898 		    ent->cache_addr.len == xprt->xp_rtaddr.len &&
899 		    (memcmp(ent->cache_addr.buf, xprt->xp_rtaddr.buf,
900 		    xprt->xp_rtaddr.len) == 0)) {
901 #ifdef RPC_CACHE_DEBUG
902 			if (nconf = getnetconfigent(xprt->xp_netid)) {
903 				uaddr = taddr2uaddr(nconf, &xprt->xp_rtaddr);
904 				freenetconfigent(nconf);
905 				printf(
906 	"cache entry found for xid=%x prog=%d vers=%d proc=%d for rmtaddr=%s\n",
907 				    su->su_xid, msg->rm_call.cb_prog,
908 				    msg->rm_call.cb_vers,
909 				    msg->rm_call.cb_proc, uaddr);
910 				free(uaddr);
911 			}
912 #endif
913 			*replyp = ent->cache_reply;
914 			*replylenp = ent->cache_replylen;
915 			(void) mutex_unlock(&dupreq_lock);
916 			return (1);
917 		}
918 	}
919 	/*
920 	 * Failed to find entry
921 	 * Remember a few things so we can do a set later
922 	 */
923 	uc->uc_proc = msg->rm_call.cb_proc;
924 	uc->uc_vers = msg->rm_call.cb_vers;
925 	uc->uc_prog = msg->rm_call.cb_prog;
926 	(void) mutex_unlock(&dupreq_lock);
927 	return (0);
928 }
929