xref: /netbsd-src/lib/libc/rpc/clnt_generic.c (revision 4472dbe5e3bd91ef2540bada7a7ca7384627ff9b)
1 /*	$NetBSD: clnt_generic.c,v 1.16 2000/06/02 23:11:07 fvdl 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  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
33  */
34 
35 /* #ident	"@(#)clnt_generic.c	1.20	94/05/03 SMI" */
36 
37 #if 0
38 #if !defined(lint) && defined(SCCSIDS)
39 static char sccsid[] = "@(#)clnt_generic.c 1.32 89/03/16 Copyr 1988 Sun Micro";
40 #endif
41 #endif
42 
43 #include "namespace.h"
44 #include "reentrant.h"
45 #include <sys/types.h>
46 #include <sys/socket.h>
47 #include <netinet/in.h>
48 #include <netinet/tcp.h>
49 #include <stdio.h>
50 #include <errno.h>
51 #include <rpc/rpc.h>
52 #include <string.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 #include "rpc_com.h"
56 
57 #ifdef __weak_alias
58 __weak_alias(clnt_create_vers,_clnt_create_vers)
59 __weak_alias(clnt_create,_clnt_create)
60 __weak_alias(clnt_tp_create,_clnt_tp_create)
61 __weak_alias(clnt_tli_create,_clnt_tli_create)
62 #endif
63 
64 /*
65  * Generic client creation with version checking the value of
66  * vers_out is set to the highest server supported value
67  * vers_low <= vers_out <= vers_high  AND an error results
68  * if this can not be done.
69  */
70 CLIENT *
71 clnt_create_vers(hostname, prog, vers_out, vers_low, vers_high, nettype)
72 	const char *hostname;
73 	rpcprog_t prog;
74 	rpcvers_t *vers_out;
75 	rpcvers_t vers_low;
76 	rpcvers_t vers_high;
77 	const char *nettype;
78 {
79 	CLIENT *clnt;
80 	struct timeval to;
81 	enum clnt_stat rpc_stat;
82 	struct rpc_err rpcerr;
83 
84 	clnt = clnt_create(hostname, prog, vers_high, nettype);
85 	if (clnt == NULL) {
86 		return (NULL);
87 	}
88 	to.tv_sec = 10;
89 	to.tv_usec = 0;
90 	rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
91 			(char *) NULL, (xdrproc_t) xdr_void, (char *) NULL, to);
92 	if (rpc_stat == RPC_SUCCESS) {
93 		*vers_out = vers_high;
94 		return (clnt);
95 	}
96 	if (rpc_stat == RPC_PROGVERSMISMATCH) {
97 		unsigned long minvers, maxvers;
98 
99 		clnt_geterr(clnt, &rpcerr);
100 		minvers = rpcerr.re_vers.low;
101 		maxvers = rpcerr.re_vers.high;
102 		if (maxvers < vers_high)
103 			vers_high = maxvers;
104 		if (minvers > vers_low)
105 			vers_low = minvers;
106 		if (vers_low > vers_high) {
107 			goto error;
108 		}
109 		CLNT_CONTROL(clnt, CLSET_VERS, (char *)&vers_high);
110 		rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
111 				(char *) NULL, (xdrproc_t) xdr_void,
112 				(char *) NULL, to);
113 		if (rpc_stat == RPC_SUCCESS) {
114 			*vers_out = vers_high;
115 			return (clnt);
116 		}
117 	}
118 	clnt_geterr(clnt, &rpcerr);
119 
120 error:
121 	rpc_createerr.cf_stat = rpc_stat;
122 	rpc_createerr.cf_error = rpcerr;
123 	clnt_destroy(clnt);
124 	return (NULL);
125 }
126 
127 /*
128  * Top level client creation routine.
129  * Generic client creation: takes (servers name, program-number, nettype) and
130  * returns client handle. Default options are set, which the user can
131  * change using the rpc equivalent of ioctl()'s.
132  *
133  * It tries for all the netids in that particular class of netid until
134  * it succeeds.
135  * XXX The error message in the case of failure will be the one
136  * pertaining to the last create error.
137  *
138  * It calls clnt_tp_create();
139  */
140 CLIENT *
141 clnt_create(hostname, prog, vers, nettype)
142 	const char *hostname;				/* server name */
143 	rpcprog_t prog;				/* program number */
144 	rpcvers_t vers;				/* version number */
145 	const char *nettype;				/* net type */
146 {
147 	struct netconfig *nconf;
148 	CLIENT *clnt = NULL;
149 	void *handle;
150 	enum clnt_stat	save_cf_stat = RPC_SUCCESS;
151 	struct rpc_err	save_cf_error;
152 
153 
154 	if ((handle = __rpc_setconf((char *) nettype)) == NULL) {
155 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
156 		return ((CLIENT *)NULL);
157 	}
158 	rpc_createerr.cf_stat = RPC_SUCCESS;
159 	while (clnt == (CLIENT *)NULL) {
160 		if ((nconf = __rpc_getconf(handle)) == NULL) {
161 			if (rpc_createerr.cf_stat == RPC_SUCCESS)
162 				rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
163 			break;
164 		}
165 #ifdef CLNT_DEBUG
166 		printf("trying netid %s\n", nconf->nc_netid);
167 #endif
168 		clnt = clnt_tp_create(hostname, prog, vers, nconf);
169 		if (clnt)
170 			break;
171 		else
172 			/*
173 			 *	Since we didn't get a name-to-address
174 			 *	translation failure here, we remember
175 			 *	this particular error.  The object of
176 			 *	this is to enable us to return to the
177 			 *	caller a more-specific error than the
178 			 *	unhelpful ``Name to address translation
179 			 *	failed'' which might well occur if we
180 			 *	merely returned the last error (because
181 			 *	the local loopbacks are typically the
182 			 *	last ones in /etc/netconfig and the most
183 			 *	likely to be unable to translate a host
184 			 *	name).
185 			 */
186 			if (rpc_createerr.cf_stat != RPC_N2AXLATEFAILURE) {
187 				save_cf_stat = rpc_createerr.cf_stat;
188 				save_cf_error = rpc_createerr.cf_error;
189 			}
190 	}
191 
192 	/*
193 	 *	Attempt to return an error more specific than ``Name to address
194 	 *	translation failed''
195 	 */
196 	if ((rpc_createerr.cf_stat == RPC_N2AXLATEFAILURE) &&
197 		(save_cf_stat != RPC_SUCCESS)) {
198 		rpc_createerr.cf_stat = save_cf_stat;
199 		rpc_createerr.cf_error = save_cf_error;
200 	}
201 	__rpc_endconf(handle);
202 	return (clnt);
203 }
204 
205 /*
206  * Generic client creation: takes (servers name, program-number, netconf) and
207  * returns client handle. Default options are set, which the user can
208  * change using the rpc equivalent of ioctl()'s : clnt_control()
209  * It finds out the server address from rpcbind and calls clnt_tli_create()
210  */
211 CLIENT *
212 clnt_tp_create(hostname, prog, vers, nconf)
213 	const char *hostname;				/* server name */
214 	rpcprog_t prog;				/* program number */
215 	rpcvers_t vers;				/* version number */
216 	const register struct netconfig *nconf;	/* net config struct */
217 {
218 	struct netbuf *svcaddr;			/* servers address */
219 	CLIENT *cl = NULL;			/* client handle */
220 
221 	if (nconf == (struct netconfig *)NULL) {
222 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
223 		return ((CLIENT *)NULL);
224 	}
225 
226 	/*
227 	 * Get the address of the server
228 	 */
229 	if ((svcaddr = __rpcb_findaddr(prog, vers, nconf, hostname,
230 		&cl)) == NULL) {
231 		/* appropriate error number is set by rpcbind libraries */
232 		return ((CLIENT *)NULL);
233 	}
234 	if (cl == (CLIENT *)NULL) {
235 		cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
236 					prog, vers, 0, 0);
237 	} else {
238 		/* Reuse the CLIENT handle and change the appropriate fields */
239 		if (CLNT_CONTROL(cl, CLSET_SVC_ADDR, (void *)svcaddr) == TRUE) {
240 			if (cl->cl_netid == NULL)
241 				cl->cl_netid = strdup(nconf->nc_netid);
242 			if (cl->cl_tp == NULL)
243 				cl->cl_tp = strdup(nconf->nc_device);
244 			(void) CLNT_CONTROL(cl, CLSET_PROG, (void *)&prog);
245 			(void) CLNT_CONTROL(cl, CLSET_VERS, (void *)&vers);
246 		} else {
247 			CLNT_DESTROY(cl);
248 			cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
249 					prog, vers, 0, 0);
250 		}
251 	}
252 	free(svcaddr->buf);
253 	free(svcaddr);
254 	return (cl);
255 }
256 
257 /*
258  * Generic client creation:  returns client handle.
259  * Default options are set, which the user can
260  * change using the rpc equivalent of ioctl()'s : clnt_control().
261  * If fd is RPC_ANYFD, it will be opened using nconf.
262  * It will be bound if not so.
263  * If sizes are 0; appropriate defaults will be chosen.
264  */
265 CLIENT *
266 clnt_tli_create(fd, nconf, svcaddr, prog, vers, sendsz, recvsz)
267 	register int fd;		/* fd */
268 	const struct netconfig *nconf;	/* netconfig structure */
269 	const struct netbuf *svcaddr;		/* servers address */
270 	rpcprog_t prog;			/* program number */
271 	rpcvers_t vers;			/* version number */
272 	u_int sendsz;			/* send size */
273 	u_int recvsz;			/* recv size */
274 {
275 	CLIENT *cl;			/* client handle */
276 	bool_t madefd = FALSE;		/* whether fd opened here */
277 	long servtype;
278 	int one = 1;
279 	struct __rpc_sockinfo si;
280 
281 	if (fd == RPC_ANYFD) {
282 		if (nconf == (struct netconfig *)NULL) {
283 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
284 			return ((CLIENT *)NULL);
285 		}
286 
287 		fd = __rpc_nconf2fd(nconf);
288 
289 		if (fd == -1)
290 			goto err;
291 
292 		madefd = TRUE;
293 		servtype = nconf->nc_semantics;
294 		if (!__rpc_fd2sockinfo(fd, &si))
295 			goto err;
296 	} else {
297 		if (!__rpc_fd2sockinfo(fd, &si))
298 			goto err;
299 		servtype = __rpc_socktype2seman(si.si_socktype);
300 		if (servtype == -1) {
301 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
302 			return NULL;
303 		}
304 
305 	}
306 
307 	if (si.si_af != ((struct sockaddr *)svcaddr->buf)->sa_family) {
308 		rpc_createerr.cf_stat = RPC_UNKNOWNHOST;	/* XXX */
309 		goto err1;
310 	}
311 
312 	switch (servtype) {
313 	case NC_TPI_COTS_ORD:
314 		cl = clnt_vc_create(fd, svcaddr, prog, vers, sendsz, recvsz);
315 		if (!nconf || !cl)
316 			break;
317 		/* XXX fvdl - is this useful? */
318 		if (strncmp(nconf->nc_protofmly, "inet", 4) == 0)
319 			setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one,
320 			    sizeof (one));
321 		break;
322 	case NC_TPI_CLTS:
323 		cl = clnt_dg_create(fd, svcaddr, prog, vers, sendsz, recvsz);
324 		break;
325 	default:
326 		goto err;
327 	}
328 
329 	if (cl == (CLIENT *)NULL)
330 		goto err1; /* borrow errors from clnt_dg/vc creates */
331 	if (nconf) {
332 		cl->cl_netid = strdup(nconf->nc_netid);
333 		cl->cl_tp = strdup(nconf->nc_device);
334 	} else {
335 		cl->cl_netid = "";
336 		cl->cl_tp = "";
337 	}
338 	if (madefd) {
339 		(void) CLNT_CONTROL(cl, CLSET_FD_CLOSE, (char *)NULL);
340 /*		(void) CLNT_CONTROL(cl, CLSET_POP_TIMOD, (char *) NULL);  */
341 	};
342 
343 	return (cl);
344 
345 err:
346 	rpc_createerr.cf_stat = RPC_SYSTEMERROR;
347 	rpc_createerr.cf_error.re_errno = errno;
348 err1:	if (madefd)
349 		(void) close(fd);
350 	return ((CLIENT *)NULL);
351 }
352