xref: /netbsd-src/lib/libc/rpc/clnt_generic.c (revision b7ae68fde0d8ef1c03714e8bbb1ee7c6118ea93b)
1 /*	$NetBSD: clnt_generic.c,v 1.26 2006/06/22 19:35:34 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  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
33  */
34 
35 /* #ident	"@(#)clnt_generic.c	1.20	94/05/03 SMI" */
36 
37 #include <sys/cdefs.h>
38 #if defined(LIBC_SCCS) && !defined(lint)
39 #if 0
40 static char sccsid[] = "@(#)clnt_generic.c 1.32 89/03/16 Copyr 1988 Sun Micro";
41 #else
42 __RCSID("$NetBSD: clnt_generic.c,v 1.26 2006/06/22 19:35:34 christos Exp $");
43 #endif
44 #endif
45 
46 #include "namespace.h"
47 #include "reentrant.h"
48 #include <sys/types.h>
49 #include <sys/socket.h>
50 #include <netinet/in.h>
51 #include <assert.h>
52 #include <stdio.h>
53 #include <errno.h>
54 #include <rpc/rpc.h>
55 #include <rpc/nettype.h>
56 #include <string.h>
57 #include <stdlib.h>
58 #include <unistd.h>
59 #include "rpc_internal.h"
60 
61 #ifdef __weak_alias
62 __weak_alias(clnt_create_vers,_clnt_create_vers)
63 __weak_alias(clnt_create,_clnt_create)
64 __weak_alias(clnt_tp_create,_clnt_tp_create)
65 __weak_alias(clnt_tli_create,_clnt_tli_create)
66 #endif
67 
68 /*
69  * Generic client creation with version checking the value of
70  * vers_out is set to the highest server supported value
71  * vers_low <= vers_out <= vers_high  AND an error results
72  * if this can not be done.
73  */
74 CLIENT *
75 clnt_create_vers(hostname, prog, vers_out, vers_low, vers_high, nettype)
76 	const char *hostname;
77 	rpcprog_t prog;
78 	rpcvers_t *vers_out;
79 	rpcvers_t vers_low;
80 	rpcvers_t vers_high;
81 	const char *nettype;
82 {
83 	CLIENT *clnt;
84 	struct timeval to;
85 	enum clnt_stat rpc_stat;
86 	struct rpc_err rpcerr;
87 
88 	_DIAGASSERT(hostname != NULL);
89 	_DIAGASSERT(vers_out != NULL);
90 	/* XXX: nettype appears to support being NULL */
91 
92 	clnt = clnt_create(hostname, prog, vers_high, nettype);
93 	if (clnt == NULL) {
94 		return (NULL);
95 	}
96 	to.tv_sec = 10;
97 	to.tv_usec = 0;
98 	rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
99 			(char *) NULL, (xdrproc_t) xdr_void, (char *) NULL, to);
100 	if (rpc_stat == RPC_SUCCESS) {
101 		*vers_out = vers_high;
102 		return (clnt);
103 	}
104 	if (rpc_stat == RPC_PROGVERSMISMATCH) {
105 		unsigned long minvers, maxvers;
106 
107 		clnt_geterr(clnt, &rpcerr);
108 		minvers = rpcerr.re_vers.low;
109 		maxvers = rpcerr.re_vers.high;
110 		if (maxvers < vers_high)
111 			vers_high = (rpcvers_t)maxvers;
112 		if (minvers > vers_low)
113 			vers_low = (rpcvers_t)minvers;
114 		if (vers_low > vers_high) {
115 			goto error;
116 		}
117 		CLNT_CONTROL(clnt, CLSET_VERS, (char *)(void *)&vers_high);
118 		rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
119 				(char *) NULL, (xdrproc_t) xdr_void,
120 				(char *) NULL, to);
121 		if (rpc_stat == RPC_SUCCESS) {
122 			*vers_out = vers_high;
123 			return (clnt);
124 		}
125 	}
126 	clnt_geterr(clnt, &rpcerr);
127 
128 error:
129 	rpc_createerr.cf_stat = rpc_stat;
130 	rpc_createerr.cf_error = rpcerr;
131 	clnt_destroy(clnt);
132 	return (NULL);
133 }
134 
135 /*
136  * Top level client creation routine.
137  * Generic client creation: takes (servers name, program-number, nettype) and
138  * returns client handle. Default options are set, which the user can
139  * change using the rpc equivalent of ioctl()'s.
140  *
141  * It tries for all the netids in that particular class of netid until
142  * it succeeds.
143  * XXX The error message in the case of failure will be the one
144  * pertaining to the last create error.
145  *
146  * It calls clnt_tp_create();
147  */
148 CLIENT *
149 clnt_create(hostname, prog, vers, nettype)
150 	const char *hostname;				/* server name */
151 	rpcprog_t prog;				/* program number */
152 	rpcvers_t vers;				/* version number */
153 	const char *nettype;				/* net type */
154 {
155 	struct netconfig *nconf;
156 	CLIENT *clnt = NULL;
157 	void *handle;
158 	enum clnt_stat	save_cf_stat = RPC_SUCCESS;
159 	struct rpc_err	save_cf_error;
160 
161 	_DIAGASSERT(hostname != NULL);
162 	/* XXX: nettype appears to support being NULL */
163 
164 	if ((handle = __rpc_setconf(nettype)) == NULL) {
165 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
166 		return (NULL);
167 	}
168 	rpc_createerr.cf_stat = RPC_SUCCESS;
169 	while (clnt == NULL) {
170 		if ((nconf = __rpc_getconf(handle)) == NULL) {
171 			if (rpc_createerr.cf_stat == RPC_SUCCESS)
172 				rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
173 			break;
174 		}
175 #ifdef CLNT_DEBUG
176 		printf("trying netid %s\n", nconf->nc_netid);
177 #endif
178 		clnt = clnt_tp_create(hostname, prog, vers, nconf);
179 		if (clnt)
180 			break;
181 		else
182 			/*
183 			 *	Since we didn't get a name-to-address
184 			 *	translation failure here, we remember
185 			 *	this particular error.  The object of
186 			 *	this is to enable us to return to the
187 			 *	caller a more-specific error than the
188 			 *	unhelpful ``Name to address translation
189 			 *	failed'' which might well occur if we
190 			 *	merely returned the last error (because
191 			 *	the local loopbacks are typically the
192 			 *	last ones in /etc/netconfig and the most
193 			 *	likely to be unable to translate a host
194 			 *	name).
195 			 */
196 			if (rpc_createerr.cf_stat != RPC_N2AXLATEFAILURE) {
197 				save_cf_stat = rpc_createerr.cf_stat;
198 				save_cf_error = rpc_createerr.cf_error;
199 			}
200 	}
201 
202 	/*
203 	 *	Attempt to return an error more specific than ``Name to address
204 	 *	translation failed''
205 	 */
206 	if ((rpc_createerr.cf_stat == RPC_N2AXLATEFAILURE) &&
207 		(save_cf_stat != RPC_SUCCESS)) {
208 		rpc_createerr.cf_stat = save_cf_stat;
209 		rpc_createerr.cf_error = save_cf_error;
210 	}
211 	__rpc_endconf(handle);
212 	return (clnt);
213 }
214 
215 /*
216  * Generic client creation: takes (servers name, program-number, netconf) and
217  * returns client handle. Default options are set, which the user can
218  * change using the rpc equivalent of ioctl()'s : clnt_control()
219  * It finds out the server address from rpcbind and calls clnt_tli_create()
220  */
221 CLIENT *
222 clnt_tp_create(hostname, prog, vers, nconf)
223 	const char *hostname;			/* server name */
224 	rpcprog_t prog;				/* program number */
225 	rpcvers_t vers;				/* version number */
226 	const struct netconfig *nconf;		/* net config struct */
227 {
228 	struct netbuf *svcaddr;			/* servers address */
229 	CLIENT *cl = NULL;			/* client handle */
230 
231 	_DIAGASSERT(hostname != NULL);
232 	/* nconf is handled below */
233 
234 	if (nconf == NULL) {
235 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
236 		return (NULL);
237 	}
238 
239 	/*
240 	 * Get the address of the server
241 	 */
242 	if ((svcaddr = __rpcb_findaddr(prog, vers, nconf, hostname,
243 		&cl)) == NULL) {
244 		/* appropriate error number is set by rpcbind libraries */
245 		return (NULL);
246 	}
247 	if (cl == NULL) {
248 		cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
249 					prog, vers, 0, 0);
250 	} else {
251 		/* Reuse the CLIENT handle and change the appropriate fields */
252 		if (CLNT_CONTROL(cl, CLSET_SVC_ADDR, (void *)svcaddr) == TRUE) {
253 			if (cl->cl_netid == NULL)
254 				cl->cl_netid = strdup(nconf->nc_netid);
255 			if (cl->cl_tp == NULL)
256 				cl->cl_tp = strdup(nconf->nc_device);
257 			(void) CLNT_CONTROL(cl, CLSET_PROG, (void *)&prog);
258 			(void) CLNT_CONTROL(cl, CLSET_VERS, (void *)&vers);
259 		} else {
260 			CLNT_DESTROY(cl);
261 			cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
262 					prog, vers, 0, 0);
263 		}
264 	}
265 	free(svcaddr->buf);
266 	free(svcaddr);
267 	return (cl);
268 }
269 
270 /*
271  * Generic client creation:  returns client handle.
272  * Default options are set, which the user can
273  * change using the rpc equivalent of ioctl()'s : clnt_control().
274  * If fd is RPC_ANYFD, it will be opened using nconf.
275  * It will be bound if not so.
276  * If sizes are 0; appropriate defaults will be chosen.
277  */
278 CLIENT *
279 clnt_tli_create(fd, nconf, svcaddr, prog, vers, sendsz, recvsz)
280 	int fd;				/* fd */
281 	const struct netconfig *nconf;	/* netconfig structure */
282 	const struct netbuf *svcaddr;	/* servers address */
283 	rpcprog_t prog;			/* program number */
284 	rpcvers_t vers;			/* version number */
285 	u_int sendsz;			/* send size */
286 	u_int recvsz;			/* recv size */
287 {
288 	CLIENT *cl;			/* client handle */
289 	bool_t madefd = FALSE;		/* whether fd opened here */
290 	long servtype;
291 	struct __rpc_sockinfo si;
292 
293 	/* nconf is handled below */
294 	_DIAGASSERT(svcaddr != NULL);
295 
296 	if (fd == RPC_ANYFD) {
297 		if (nconf == NULL) {
298 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
299 			return (NULL);
300 		}
301 
302 		fd = __rpc_nconf2fd(nconf);
303 
304 		if (fd == -1)
305 			goto err;
306 
307 		madefd = TRUE;
308 		servtype = nconf->nc_semantics;
309 		if (!__rpc_fd2sockinfo(fd, &si))
310 			goto err;
311 
312 		bindresvport(fd, NULL);
313 	} else {
314 		if (!__rpc_fd2sockinfo(fd, &si))
315 			goto err;
316 		servtype = __rpc_socktype2seman(si.si_socktype);
317 		if (servtype == -1) {
318 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
319 			return NULL;
320 		}
321 
322 	}
323 
324 	if (si.si_af != ((struct sockaddr *)svcaddr->buf)->sa_family) {
325 		rpc_createerr.cf_stat = RPC_UNKNOWNHOST;	/* XXX */
326 		goto err1;
327 	}
328 
329 	switch (servtype) {
330 	case NC_TPI_COTS_ORD:
331 		cl = clnt_vc_create(fd, svcaddr, prog, vers, sendsz, recvsz);
332 		if (!nconf || !cl)
333 			break;
334 		__rpc_setnodelay(fd, &si);
335 		break;
336 	case NC_TPI_CLTS:
337 		cl = clnt_dg_create(fd, svcaddr, prog, vers, sendsz, recvsz);
338 		break;
339 	default:
340 		goto err;
341 	}
342 
343 	if (cl == NULL)
344 		goto err1; /* borrow errors from clnt_dg/vc creates */
345 	if (nconf) {
346 		cl->cl_netid = strdup(nconf->nc_netid);
347 		cl->cl_tp = strdup(nconf->nc_device);
348 	} else {
349 		cl->cl_netid = __UNCONST("");
350 		cl->cl_tp = __UNCONST("");
351 	}
352 	if (madefd) {
353 		(void) CLNT_CONTROL(cl, CLSET_FD_CLOSE, NULL);
354 /*		(void) CLNT_CONTROL(cl, CLSET_POP_TIMOD, (char *) NULL);  */
355 	};
356 
357 	return (cl);
358 
359 err:
360 	rpc_createerr.cf_stat = RPC_SYSTEMERROR;
361 	rpc_createerr.cf_error.re_errno = errno;
362 err1:	if (madefd)
363 		(void) close(fd);
364 	return (NULL);
365 }
366