xref: /illumos-gate/usr/src/lib/libnsl/rpc/svc_simple.c (revision 22c9e08b20c7848675e1e097ca3fcbcf8b549fba)
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 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
27 /* All Rights Reserved */
28 /*
29  * Portions of this source code were derived from Berkeley
30  * 4.3 BSD under license from the Regents of the University of
31  * California.
32  */
33 
34 #pragma ident	"%Z%%M%	%I%	%E% SMI"
35 
36 /*
37  * svc_simple.c
38  * Simplified front end to rpc.
39  */
40 
41 /*
42  * This interface creates a virtual listener for all the services
43  * started thru rpc_reg(). It listens on the same endpoint for
44  * all the services and then executes the corresponding service
45  * for the given prognum and procnum.
46  */
47 
48 #include "mt.h"
49 #include "rpc_mt.h"
50 #include <errno.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <rpc/rpc.h>
55 #include <sys/types.h>
56 #include <syslog.h>
57 #include <rpc/nettype.h>
58 
59 extern int use_portmapper;
60 
61 static struct proglst {
62 	char *(*p_progname)();
63 	rpcprog_t p_prognum;
64 	rpcvers_t p_versnum;
65 	rpcproc_t p_procnum;
66 	SVCXPRT *p_transp;
67 	char *p_netid;
68 	char *p_xdrbuf;
69 	int p_recvsz;
70 	xdrproc_t p_inproc, p_outproc;
71 	struct proglst *p_nxt;
72 } *proglst;
73 
74 static void universal();
75 
76 static const char rpc_reg_err[] = "%s: %s";
77 static const char rpc_reg_msg[] = "rpc_reg: ";
78 static const char __reg_err1[] = "can't find appropriate transport";
79 static const char __reg_err3[] = "unsupported transport size";
80 static const char __no_mem_str[] = "out of memory";
81 /*
82  * For simplified, easy to use kind of rpc interfaces.
83  * nettype indicates the type of transport on which the service will be
84  * listening. Used for conservation of the system resource. Only one
85  * handle is created for all the services (actually one of each netid)
86  * and same xdrbuf is used for same netid. The size of the arguments
87  * is also limited by the recvsize for that transport, even if it is
88  * a COTS transport. This may be wrong, but for cases like these, they
89  * should not use the simplified interfaces like this.
90  */
91 
92 int
93 rpc_reg(const rpcprog_t prognum, const rpcvers_t versnum,
94 	const rpcproc_t procnum, char *(*progname)(), const xdrproc_t inproc,
95 	const xdrproc_t outproc, const char *nettype)
96 {
97 	struct netconfig *nconf;
98 	int done = FALSE;
99 	void *handle;
100 	extern mutex_t proglst_lock;
101 
102 	if (procnum == NULLPROC) {
103 		(void) syslog(LOG_ERR, (const char *) "%s: %s %d",
104 			rpc_reg_msg,
105 			(const char *) "can't reassign procedure number %d",
106 			NULLPROC);
107 		return (-1);
108 	}
109 
110 	if (nettype == NULL)
111 		nettype = "netpath";		/* The default behavior */
112 	if ((handle = __rpc_setconf((char *)nettype)) == NULL) {
113 		(void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg, __reg_err1);
114 		return (-1);
115 	}
116 /* VARIABLES PROTECTED BY proglst_lock: proglst */
117 	(void) mutex_lock(&proglst_lock);
118 	while (nconf = __rpc_getconf(handle)) {
119 		struct proglst *pl;
120 		SVCXPRT *svcxprt;
121 		int madenow;
122 		uint_t recvsz;
123 		char *xdrbuf;
124 		char *netid;
125 
126 		madenow = FALSE;
127 		svcxprt = NULL;
128 		for (pl = proglst; pl; pl = pl->p_nxt)
129 			if (strcmp(pl->p_netid, nconf->nc_netid) == 0) {
130 				svcxprt = pl->p_transp;
131 				xdrbuf = pl->p_xdrbuf;
132 				recvsz = pl->p_recvsz;
133 				netid = pl->p_netid;
134 				break;
135 			}
136 
137 		if (svcxprt == NULL) {
138 			struct t_info tinfo;
139 
140 			svcxprt = svc_tli_create(RPC_ANYFD, nconf, NULL, 0, 0);
141 			if (svcxprt == NULL)
142 				continue;
143 			if (t_getinfo(svcxprt->xp_fd, &tinfo) == -1) {
144 				char errorstr[100];
145 
146 				__tli_sys_strerror(errorstr, sizeof (errorstr),
147 						t_errno, errno);
148 				(void) syslog(LOG_ERR, "%s : %s : %s",
149 					rpc_reg_msg, "t_getinfo failed",
150 					errorstr);
151 				SVC_DESTROY(svcxprt);
152 				continue;
153 			}
154 			if ((recvsz = __rpc_get_t_size(0, tinfo.tsdu)) == 0) {
155 				(void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
156 					__reg_err3);
157 				SVC_DESTROY(svcxprt);
158 				continue;
159 			}
160 			if (((xdrbuf = malloc((unsigned)recvsz)) == NULL) ||
161 				((netid = strdup(nconf->nc_netid)) == NULL)) {
162 				(void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
163 					__no_mem_str);
164 				SVC_DESTROY(svcxprt);
165 				break;
166 			}
167 			madenow = TRUE;
168 		}
169 		/*
170 		 * Check if this (program, version, netid) had already been
171 		 * registered.  The check may save a few RPC calls to rpcbind
172 		 */
173 		for (pl = proglst; pl; pl = pl->p_nxt)
174 			if ((pl->p_prognum == prognum) &&
175 				(pl->p_versnum == versnum) &&
176 				(strcmp(pl->p_netid, netid) == 0))
177 				break;
178 		if (pl == NULL) { /* Not yet */
179 			/*
180 			 * Note that if we're using a portmapper
181 			 * instead of rpcbind then we can't do an
182 			 * unregister operation here.
183 			 *
184 			 * The reason is that the portmapper unset
185 			 * operation removes all the entries for a
186 			 * given program/version regardelss of
187 			 * transport protocol.
188 			 *
189 			 * The caller of this routine needs to ensure
190 			 * that __pmap_unset() has been called for all
191 			 * program/version service pairs they plan
192 			 * to support before they start registering
193 			 * each program/version/protocol triplet.
194 			 */
195 			if (!use_portmapper)
196 				(void) rpcb_unset(prognum, versnum, nconf);
197 		} else {
198 			/* so that svc_reg does not call rpcb_set() */
199 			nconf = NULL;
200 		}
201 
202 		if (!svc_reg(svcxprt, prognum, versnum, universal, nconf)) {
203 			(void) syslog(LOG_ERR,
204 				"%s couldn't register prog %d vers %d for %s",
205 				rpc_reg_msg, prognum, versnum, netid);
206 			if (madenow) {
207 				SVC_DESTROY(svcxprt);
208 				free(xdrbuf);
209 				free(netid);
210 			}
211 			continue;
212 		}
213 
214 		pl = malloc(sizeof (struct proglst));
215 		if (pl == NULL) {
216 			(void) syslog(LOG_ERR, rpc_reg_err, rpc_reg_msg,
217 					__no_mem_str);
218 			if (madenow) {
219 				SVC_DESTROY(svcxprt);
220 				free(xdrbuf);
221 				free(netid);
222 			}
223 			break;
224 		}
225 		pl->p_progname = progname;
226 		pl->p_prognum = prognum;
227 		pl->p_versnum = versnum;
228 		pl->p_procnum = procnum;
229 		pl->p_inproc = inproc;
230 		pl->p_outproc = outproc;
231 		pl->p_transp = svcxprt;
232 		pl->p_xdrbuf = xdrbuf;
233 		pl->p_recvsz = recvsz;
234 		pl->p_netid = netid;
235 		pl->p_nxt = proglst;
236 		proglst = pl;
237 		done = TRUE;
238 	}
239 	__rpc_endconf(handle);
240 	(void) mutex_unlock(&proglst_lock);
241 
242 	if (done == FALSE) {
243 		(void) syslog(LOG_ERR,
244 			(const char *) "%s cant find suitable transport for %s",
245 			rpc_reg_msg, nettype);
246 		return (-1);
247 	}
248 	return (0);
249 }
250 
251 /*
252  * The universal handler for the services registered using registerrpc.
253  * It handles both the connectionless and the connection oriented cases.
254  */
255 
256 static void
257 universal(struct svc_req *rqstp, SVCXPRT *transp)
258 {
259 	rpcprog_t prog;
260 	rpcvers_t vers;
261 	rpcproc_t proc;
262 	char *outdata;
263 	char *xdrbuf;
264 	struct proglst *pl;
265 	extern mutex_t proglst_lock;
266 
267 	/*
268 	 * enforce "procnum 0 is echo" convention
269 	 */
270 	if (rqstp->rq_proc == NULLPROC) {
271 		if (svc_sendreply(transp, (xdrproc_t)xdr_void, NULL) == FALSE) {
272 			(void) syslog(LOG_ERR,
273 				(const char *) "svc_sendreply failed");
274 		}
275 		return;
276 	}
277 	prog = rqstp->rq_prog;
278 	vers = rqstp->rq_vers;
279 	proc = rqstp->rq_proc;
280 	(void) mutex_lock(&proglst_lock);
281 	for (pl = proglst; pl; pl = pl->p_nxt) {
282 		if (pl->p_prognum == prog && pl->p_procnum == proc &&
283 			pl->p_versnum == vers &&
284 			(strcmp(pl->p_netid, transp->xp_netid) == 0)) {
285 			/* decode arguments into a CLEAN buffer */
286 			xdrbuf = pl->p_xdrbuf;
287 			/* Zero the arguments: reqd ! */
288 			(void) memset(xdrbuf, 0, pl->p_recvsz);
289 			/*
290 			 * Assuming that sizeof (xdrbuf) would be enough
291 			 * for the arguments; if not then the program
292 			 * may bomb. BEWARE!
293 			 */
294 			if (!svc_getargs(transp, pl->p_inproc, xdrbuf)) {
295 				svcerr_decode(transp);
296 				(void) mutex_unlock(&proglst_lock);
297 				return;
298 			}
299 			outdata = (*(pl->p_progname))(xdrbuf);
300 			if (outdata == NULL &&
301 				pl->p_outproc != (xdrproc_t)xdr_void) {
302 				/* there was an error */
303 				(void) mutex_unlock(&proglst_lock);
304 				return;
305 			}
306 			if (!svc_sendreply(transp, pl->p_outproc, outdata)) {
307 				(void) syslog(LOG_ERR, (const char *)
308 			"rpc: rpc_reg trouble replying to prog %d vers %d",
309 				prog, vers);
310 				(void) mutex_unlock(&proglst_lock);
311 				return;
312 			}
313 			/* free the decoded arguments */
314 			(void) svc_freeargs(transp, pl->p_inproc, xdrbuf);
315 			(void) mutex_unlock(&proglst_lock);
316 			return;
317 		}
318 	}
319 	(void) mutex_unlock(&proglst_lock);
320 	/* This should never happen */
321 	(void) syslog(LOG_ERR, (const char *)
322 		"rpc: rpc_reg: never registered prog %d vers %d",
323 		prog, vers);
324 }
325