xref: /freebsd/lib/libc/rpc/svc_simple.c (revision a2f733abcff64628b7771a47089628b7327a88bd)
1 /*	$NetBSD: svc_simple.c,v 1.20 2000/07/06 03:10:35 christos Exp $	*/
2 
3 /*-
4  * SPDX-License-Identifier: BSD-3-Clause
5  *
6  * Copyright (c) 2009, Sun Microsystems, Inc.
7  * All rights reserved.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions are met:
11  * - Redistributions of source code must retain the above copyright notice,
12  *   this list of conditions and the following disclaimer.
13  * - Redistributions in binary form must reproduce the above copyright notice,
14  *   this list of conditions and the following disclaimer in the documentation
15  *   and/or other materials provided with the distribution.
16  * - Neither the name of Sun Microsystems, Inc. nor the names of its
17  *   contributors may be used to endorse or promote products derived
18  *   from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
21  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
24  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30  * POSSIBILITY OF SUCH DAMAGE.
31  */
32 /*
33  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
34  */
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 through 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 "namespace.h"
49 #include "reentrant.h"
50 #include <sys/types.h>
51 #include <rpc/rpc.h>
52 #include <rpc/nettype.h>
53 #include <stdio.h>
54 #include <stdlib.h>
55 #include <string.h>
56 #include <err.h>
57 #include "un-namespace.h"
58 
59 #include "rpc_com.h"
60 #include "mt_misc.h"
61 
62 static void universal(struct svc_req *, SVCXPRT *);
63 
64 static struct proglst {
65 	char *(*p_progname)(char *);
66 	rpcprog_t p_prognum;
67 	rpcvers_t p_versnum;
68 	rpcproc_t p_procnum;
69 	SVCXPRT *p_transp;
70 	char *p_netid;
71 	char *p_xdrbuf;
72 	int p_recvsz;
73 	xdrproc_t p_inproc, p_outproc;
74 	struct proglst *p_nxt;
75 } *proglst;
76 
77 static const char rpc_reg_err[] = "%s: %s";
78 static const char rpc_reg_msg[] = "rpc_reg: ";
79 static const char __reg_err1[] = "can't find appropriate transport";
80 static const char __reg_err2[] = "can't get protocol info";
81 static const char __reg_err3[] = "unsupported transport size";
82 static const char __no_mem_str[] = "out of memory";
83 
84 /*
85  * For simplified, easy to use kind of rpc interfaces.
86  * nettype indicates the type of transport on which the service will be
87  * listening. Used for conservation of the system resource. Only one
88  * handle is created for all the services (actually one of each netid)
89  * and same xdrbuf is used for same netid. The size of the arguments
90  * is also limited by the recvsize for that transport, even if it is
91  * a COTS transport. This may be wrong, but for cases like these, they
92  * should not use the simplified interfaces like this.
93  *
94  * prognum - program number
95  * versnum - version number
96  * procnum - procedure number
97  * progname - Server routine
98  * inproc, outproc - in/out XDR procedures
99  * nettype - nettype
100  */
101 int
102 rpc_reg(rpcprog_t prognum, rpcvers_t versnum, rpcproc_t procnum,
103     char *(*progname)(char *), xdrproc_t inproc, xdrproc_t outproc,
104     char *nettype)
105 {
106 	struct netconfig *nconf;
107 	int done = FALSE;
108 	void *handle;
109 
110 
111 	if (procnum == NULLPROC) {
112 		warnx("%s can't reassign procedure number %u", rpc_reg_msg,
113 			NULLPROC);
114 		return (-1);
115 	}
116 
117 	if (nettype == NULL)
118 		nettype = "netpath";		/* The default behavior */
119 	if ((handle = __rpc_setconf(nettype)) == NULL) {
120 		warnx(rpc_reg_err, rpc_reg_msg, __reg_err1);
121 		return (-1);
122 	}
123 /* VARIABLES PROTECTED BY proglst_lock: proglst */
124 	mutex_lock(&proglst_lock);
125 	while ((nconf = __rpc_getconf(handle)) != NULL) {
126 		struct proglst *pl;
127 		SVCXPRT *svcxprt;
128 		int madenow;
129 		u_int recvsz;
130 		char *xdrbuf;
131 		char *netid;
132 
133 		madenow = FALSE;
134 		svcxprt = NULL;
135 		recvsz = 0;
136 		xdrbuf = netid = NULL;
137 		for (pl = proglst; pl; pl = pl->p_nxt) {
138 			if (strcmp(pl->p_netid, nconf->nc_netid) == 0) {
139 				svcxprt = pl->p_transp;
140 				xdrbuf = pl->p_xdrbuf;
141 				recvsz = pl->p_recvsz;
142 				netid = pl->p_netid;
143 				break;
144 			}
145 		}
146 
147 		if (svcxprt == NULL) {
148 			struct __rpc_sockinfo si;
149 
150 			svcxprt = svc_tli_create(RPC_ANYFD, nconf, NULL, 0, 0);
151 			if (svcxprt == NULL)
152 				continue;
153 			if (!__rpc_fd2sockinfo(svcxprt->xp_fd, &si)) {
154 				warnx(rpc_reg_err, rpc_reg_msg, __reg_err2);
155 				SVC_DESTROY(svcxprt);
156 				continue;
157 			}
158 			recvsz = __rpc_get_t_size(si.si_af, si.si_proto, 0);
159 			if (recvsz == 0) {
160 				warnx(rpc_reg_err, rpc_reg_msg, __reg_err3);
161 				SVC_DESTROY(svcxprt);
162 				continue;
163 			}
164 			if (((xdrbuf = malloc((unsigned)recvsz)) == NULL) ||
165 				((netid = strdup(nconf->nc_netid)) == NULL)) {
166 				warnx(rpc_reg_err, rpc_reg_msg, __no_mem_str);
167 				free(xdrbuf);
168 				free(netid);
169 				SVC_DESTROY(svcxprt);
170 				break;
171 			}
172 			madenow = TRUE;
173 		}
174 		/*
175 		 * Check if this (program, version, netid) had already been
176 		 * registered.  The check may save a few RPC calls to rpcbind
177 		 */
178 		for (pl = proglst; pl; pl = pl->p_nxt)
179 			if ((pl->p_prognum == prognum) &&
180 				(pl->p_versnum == versnum) &&
181 				(strcmp(pl->p_netid, netid) == 0))
182 				break;
183 		if (pl == NULL) { /* Not yet */
184 			(void) rpcb_unset(prognum, versnum, nconf);
185 		} else {
186 			/* so that svc_reg does not call rpcb_set() */
187 			nconf = NULL;
188 		}
189 
190 		if (!svc_reg(svcxprt, prognum, versnum, universal, nconf)) {
191 			warnx("%s couldn't register prog %u vers %u for %s",
192 				rpc_reg_msg, (unsigned)prognum,
193 				(unsigned)versnum, netid);
194 			if (madenow) {
195 				SVC_DESTROY(svcxprt);
196 				free(xdrbuf);
197 				free(netid);
198 			}
199 			continue;
200 		}
201 
202 		pl = malloc(sizeof (struct proglst));
203 		if (pl == NULL) {
204 			warnx(rpc_reg_err, rpc_reg_msg, __no_mem_str);
205 			if (madenow) {
206 				SVC_DESTROY(svcxprt);
207 				free(xdrbuf);
208 				free(netid);
209 			}
210 			break;
211 		}
212 		pl->p_progname = progname;
213 		pl->p_prognum = prognum;
214 		pl->p_versnum = versnum;
215 		pl->p_procnum = procnum;
216 		pl->p_inproc = inproc;
217 		pl->p_outproc = outproc;
218 		pl->p_transp = svcxprt;
219 		pl->p_xdrbuf = xdrbuf;
220 		pl->p_recvsz = recvsz;
221 		pl->p_netid = netid;
222 		pl->p_nxt = proglst;
223 		proglst = pl;
224 		done = TRUE;
225 	}
226 	__rpc_endconf(handle);
227 	mutex_unlock(&proglst_lock);
228 
229 	if (done == FALSE) {
230 		warnx("%s can't find suitable transport for %s",
231 			rpc_reg_msg, nettype);
232 		return (-1);
233 	}
234 	return (0);
235 }
236 
237 /*
238  * The universal handler for the services registered using registerrpc.
239  * It handles both the connectionless and the connection oriented cases.
240  */
241 
242 static void
243 universal(struct svc_req *rqstp, SVCXPRT *transp)
244 {
245 	rpcprog_t prog;
246 	rpcvers_t vers;
247 	rpcproc_t proc;
248 	char *outdata;
249 	char *xdrbuf;
250 	struct proglst *pl;
251 
252 	/*
253 	 * enforce "procnum 0 is echo" convention
254 	 */
255 	if (rqstp->rq_proc == NULLPROC) {
256 		if (svc_sendreply(transp, (xdrproc_t) xdr_void, NULL) ==
257 		    FALSE) {
258 			warnx("svc_sendreply failed");
259 		}
260 		return;
261 	}
262 	prog = rqstp->rq_prog;
263 	vers = rqstp->rq_vers;
264 	proc = rqstp->rq_proc;
265 	mutex_lock(&proglst_lock);
266 	for (pl = proglst; pl; pl = pl->p_nxt)
267 		if (pl->p_prognum == prog && pl->p_procnum == proc &&
268 			pl->p_versnum == vers &&
269 			(strcmp(pl->p_netid, transp->xp_netid) == 0)) {
270 			/* decode arguments into a CLEAN buffer */
271 			xdrbuf = pl->p_xdrbuf;
272 			/* Zero the arguments: reqd ! */
273 			(void) memset(xdrbuf, 0, (size_t)pl->p_recvsz);
274 			/*
275 			 * Assuming that sizeof (xdrbuf) would be enough
276 			 * for the arguments; if not then the program
277 			 * may bomb. BEWARE!
278 			 */
279 			if (!svc_getargs(transp, pl->p_inproc, xdrbuf)) {
280 				svcerr_decode(transp);
281 				mutex_unlock(&proglst_lock);
282 				return;
283 			}
284 			outdata = (*(pl->p_progname))(xdrbuf);
285 			if (outdata == NULL &&
286 				pl->p_outproc != (xdrproc_t) xdr_void){
287 				/* there was an error */
288 				mutex_unlock(&proglst_lock);
289 				return;
290 			}
291 			if (!svc_sendreply(transp, pl->p_outproc, outdata)) {
292 				warnx(
293 			"rpc: rpc_reg trouble replying to prog %u vers %u",
294 				(unsigned)prog, (unsigned)vers);
295 				mutex_unlock(&proglst_lock);
296 				return;
297 			}
298 			/* free the decoded arguments */
299 			(void)svc_freeargs(transp, pl->p_inproc, xdrbuf);
300 			mutex_unlock(&proglst_lock);
301 			return;
302 		}
303 	mutex_unlock(&proglst_lock);
304 	/* This should never happen */
305 	warnx("rpc: rpc_reg: never registered prog %u vers %u",
306 		(unsigned)prog, (unsigned)vers);
307 	return;
308 }
309