xref: /netbsd-src/lib/libc/rpc/clnt_generic.c (revision 23c8222edbfb0f0932d88a8351d3a0cf817dfb9e)
1 /*	$NetBSD: clnt_generic.c,v 1.22 2003/09/09 03:56:39 itojun 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 1.22 2003/09/09 03:56:39 itojun 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 <netinet/tcp.h>
52 #include <assert.h>
53 #include <stdio.h>
54 #include <errno.h>
55 #include <rpc/rpc.h>
56 #include <rpc/nettype.h>
57 #include <string.h>
58 #include <stdlib.h>
59 #include <unistd.h>
60 #include "rpc_internal.h"
61 
62 #ifdef __weak_alias
63 __weak_alias(clnt_create_vers,_clnt_create_vers)
64 __weak_alias(clnt_create,_clnt_create)
65 __weak_alias(clnt_tp_create,_clnt_tp_create)
66 __weak_alias(clnt_tli_create,_clnt_tli_create)
67 #endif
68 
69 /*
70  * Generic client creation with version checking the value of
71  * vers_out is set to the highest server supported value
72  * vers_low <= vers_out <= vers_high  AND an error results
73  * if this can not be done.
74  */
75 CLIENT *
76 clnt_create_vers(hostname, prog, vers_out, vers_low, vers_high, nettype)
77 	const char *hostname;
78 	rpcprog_t prog;
79 	rpcvers_t *vers_out;
80 	rpcvers_t vers_low;
81 	rpcvers_t vers_high;
82 	const char *nettype;
83 {
84 	CLIENT *clnt;
85 	struct timeval to;
86 	enum clnt_stat rpc_stat;
87 	struct rpc_err rpcerr;
88 
89 	_DIAGASSERT(hostname != NULL);
90 	_DIAGASSERT(vers_out != NULL);
91 	/* XXX: nettype appears to support being NULL */
92 
93 	clnt = clnt_create(hostname, prog, vers_high, nettype);
94 	if (clnt == NULL) {
95 		return (NULL);
96 	}
97 	to.tv_sec = 10;
98 	to.tv_usec = 0;
99 	rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
100 			(char *) NULL, (xdrproc_t) xdr_void, (char *) NULL, to);
101 	if (rpc_stat == RPC_SUCCESS) {
102 		*vers_out = vers_high;
103 		return (clnt);
104 	}
105 	if (rpc_stat == RPC_PROGVERSMISMATCH) {
106 		unsigned long minvers, maxvers;
107 
108 		clnt_geterr(clnt, &rpcerr);
109 		minvers = rpcerr.re_vers.low;
110 		maxvers = rpcerr.re_vers.high;
111 		if (maxvers < vers_high)
112 			vers_high = (rpcvers_t)maxvers;
113 		if (minvers > vers_low)
114 			vers_low = (rpcvers_t)minvers;
115 		if (vers_low > vers_high) {
116 			goto error;
117 		}
118 		CLNT_CONTROL(clnt, CLSET_VERS, (char *)(void *)&vers_high);
119 		rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
120 				(char *) NULL, (xdrproc_t) xdr_void,
121 				(char *) NULL, to);
122 		if (rpc_stat == RPC_SUCCESS) {
123 			*vers_out = vers_high;
124 			return (clnt);
125 		}
126 	}
127 	clnt_geterr(clnt, &rpcerr);
128 
129 error:
130 	rpc_createerr.cf_stat = rpc_stat;
131 	rpc_createerr.cf_error = rpcerr;
132 	clnt_destroy(clnt);
133 	return (NULL);
134 }
135 
136 /*
137  * Top level client creation routine.
138  * Generic client creation: takes (servers name, program-number, nettype) and
139  * returns client handle. Default options are set, which the user can
140  * change using the rpc equivalent of ioctl()'s.
141  *
142  * It tries for all the netids in that particular class of netid until
143  * it succeeds.
144  * XXX The error message in the case of failure will be the one
145  * pertaining to the last create error.
146  *
147  * It calls clnt_tp_create();
148  */
149 CLIENT *
150 clnt_create(hostname, prog, vers, nettype)
151 	const char *hostname;				/* server name */
152 	rpcprog_t prog;				/* program number */
153 	rpcvers_t vers;				/* version number */
154 	const char *nettype;				/* net type */
155 {
156 	struct netconfig *nconf;
157 	CLIENT *clnt = NULL;
158 	void *handle;
159 	enum clnt_stat	save_cf_stat = RPC_SUCCESS;
160 	struct rpc_err	save_cf_error;
161 
162 	_DIAGASSERT(hostname != NULL);
163 	/* XXX: nettype appears to support being NULL */
164 
165 	if ((handle = __rpc_setconf(nettype)) == NULL) {
166 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
167 		return (NULL);
168 	}
169 	rpc_createerr.cf_stat = RPC_SUCCESS;
170 	while (clnt == NULL) {
171 		if ((nconf = __rpc_getconf(handle)) == NULL) {
172 			if (rpc_createerr.cf_stat == RPC_SUCCESS)
173 				rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
174 			break;
175 		}
176 #ifdef CLNT_DEBUG
177 		printf("trying netid %s\n", nconf->nc_netid);
178 #endif
179 		clnt = clnt_tp_create(hostname, prog, vers, nconf);
180 		if (clnt)
181 			break;
182 		else
183 			/*
184 			 *	Since we didn't get a name-to-address
185 			 *	translation failure here, we remember
186 			 *	this particular error.  The object of
187 			 *	this is to enable us to return to the
188 			 *	caller a more-specific error than the
189 			 *	unhelpful ``Name to address translation
190 			 *	failed'' which might well occur if we
191 			 *	merely returned the last error (because
192 			 *	the local loopbacks are typically the
193 			 *	last ones in /etc/netconfig and the most
194 			 *	likely to be unable to translate a host
195 			 *	name).
196 			 */
197 			if (rpc_createerr.cf_stat != RPC_N2AXLATEFAILURE) {
198 				save_cf_stat = rpc_createerr.cf_stat;
199 				save_cf_error = rpc_createerr.cf_error;
200 			}
201 	}
202 
203 	/*
204 	 *	Attempt to return an error more specific than ``Name to address
205 	 *	translation failed''
206 	 */
207 	if ((rpc_createerr.cf_stat == RPC_N2AXLATEFAILURE) &&
208 		(save_cf_stat != RPC_SUCCESS)) {
209 		rpc_createerr.cf_stat = save_cf_stat;
210 		rpc_createerr.cf_error = save_cf_error;
211 	}
212 	__rpc_endconf(handle);
213 	return (clnt);
214 }
215 
216 /*
217  * Generic client creation: takes (servers name, program-number, netconf) and
218  * returns client handle. Default options are set, which the user can
219  * change using the rpc equivalent of ioctl()'s : clnt_control()
220  * It finds out the server address from rpcbind and calls clnt_tli_create()
221  */
222 CLIENT *
223 clnt_tp_create(hostname, prog, vers, nconf)
224 	const char *hostname;			/* server name */
225 	rpcprog_t prog;				/* program number */
226 	rpcvers_t vers;				/* version number */
227 	const struct netconfig *nconf;		/* net config struct */
228 {
229 	struct netbuf *svcaddr;			/* servers address */
230 	CLIENT *cl = NULL;			/* client handle */
231 
232 	_DIAGASSERT(hostname != NULL);
233 	/* nconf is handled below */
234 
235 	if (nconf == NULL) {
236 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
237 		return (NULL);
238 	}
239 
240 	/*
241 	 * Get the address of the server
242 	 */
243 	if ((svcaddr = __rpcb_findaddr(prog, vers, nconf, hostname,
244 		&cl)) == NULL) {
245 		/* appropriate error number is set by rpcbind libraries */
246 		return (NULL);
247 	}
248 	if (cl == NULL) {
249 		cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
250 					prog, vers, 0, 0);
251 	} else {
252 		/* Reuse the CLIENT handle and change the appropriate fields */
253 		if (CLNT_CONTROL(cl, CLSET_SVC_ADDR, (void *)svcaddr) == TRUE) {
254 			if (cl->cl_netid == NULL)
255 				cl->cl_netid = strdup(nconf->nc_netid);
256 			if (cl->cl_tp == NULL)
257 				cl->cl_tp = strdup(nconf->nc_device);
258 			(void) CLNT_CONTROL(cl, CLSET_PROG, (void *)&prog);
259 			(void) CLNT_CONTROL(cl, CLSET_VERS, (void *)&vers);
260 		} else {
261 			CLNT_DESTROY(cl);
262 			cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
263 					prog, vers, 0, 0);
264 		}
265 	}
266 	free(svcaddr->buf);
267 	free(svcaddr);
268 	return (cl);
269 }
270 
271 /*
272  * Generic client creation:  returns client handle.
273  * Default options are set, which the user can
274  * change using the rpc equivalent of ioctl()'s : clnt_control().
275  * If fd is RPC_ANYFD, it will be opened using nconf.
276  * It will be bound if not so.
277  * If sizes are 0; appropriate defaults will be chosen.
278  */
279 CLIENT *
280 clnt_tli_create(fd, nconf, svcaddr, prog, vers, sendsz, recvsz)
281 	int fd;				/* fd */
282 	const struct netconfig *nconf;	/* netconfig structure */
283 	const struct netbuf *svcaddr;	/* servers address */
284 	rpcprog_t prog;			/* program number */
285 	rpcvers_t vers;			/* version number */
286 	u_int sendsz;			/* send size */
287 	u_int recvsz;			/* recv size */
288 {
289 	CLIENT *cl;			/* client handle */
290 	bool_t madefd = FALSE;		/* whether fd opened here */
291 	long servtype;
292 	int one = 1;
293 	struct __rpc_sockinfo si;
294 
295 	/* nconf is handled below */
296 	_DIAGASSERT(svcaddr != NULL);
297 
298 	if (fd == RPC_ANYFD) {
299 		if (nconf == NULL) {
300 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
301 			return (NULL);
302 		}
303 
304 		fd = __rpc_nconf2fd(nconf);
305 
306 		if (fd == -1)
307 			goto err;
308 
309 		madefd = TRUE;
310 		servtype = nconf->nc_semantics;
311 		if (!__rpc_fd2sockinfo(fd, &si))
312 			goto err;
313 
314 		bindresvport(fd, NULL);
315 	} else {
316 		if (!__rpc_fd2sockinfo(fd, &si))
317 			goto err;
318 		servtype = __rpc_socktype2seman(si.si_socktype);
319 		if (servtype == -1) {
320 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
321 			return NULL;
322 		}
323 
324 	}
325 
326 	if (si.si_af != ((struct sockaddr *)svcaddr->buf)->sa_family) {
327 		rpc_createerr.cf_stat = RPC_UNKNOWNHOST;	/* XXX */
328 		goto err1;
329 	}
330 
331 	switch (servtype) {
332 	case NC_TPI_COTS_ORD:
333 		cl = clnt_vc_create(fd, svcaddr, prog, vers, sendsz, recvsz);
334 		if (!nconf || !cl)
335 			break;
336 		/* XXX fvdl - is this useful? */
337 		if (strncmp(nconf->nc_protofmly, "inet", 4) == 0)
338 			setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &one,
339 			    sizeof (one));
340 		break;
341 	case NC_TPI_CLTS:
342 		cl = clnt_dg_create(fd, svcaddr, prog, vers, sendsz, recvsz);
343 		break;
344 	default:
345 		goto err;
346 	}
347 
348 	if (cl == NULL)
349 		goto err1; /* borrow errors from clnt_dg/vc creates */
350 	if (nconf) {
351 		cl->cl_netid = strdup(nconf->nc_netid);
352 		cl->cl_tp = strdup(nconf->nc_device);
353 	} else {
354 		cl->cl_netid = "";
355 		cl->cl_tp = "";
356 	}
357 	if (madefd) {
358 		(void) CLNT_CONTROL(cl, CLSET_FD_CLOSE, NULL);
359 /*		(void) CLNT_CONTROL(cl, CLSET_POP_TIMOD, (char *) NULL);  */
360 	};
361 
362 	return (cl);
363 
364 err:
365 	rpc_createerr.cf_stat = RPC_SYSTEMERROR;
366 	rpc_createerr.cf_error.re_errno = errno;
367 err1:	if (madefd)
368 		(void) close(fd);
369 	return (NULL);
370 }
371