xref: /minix3/lib/libc/rpc/clnt_generic.c (revision 0a6a1f1d05b60e214de2f05a7310ddd1f0e590e7)
1 /*	$NetBSD: clnt_generic.c,v 1.33 2014/05/28 14:45:19 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 2010, Oracle America, Inc.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are
8  * met:
9  *
10  *     * Redistributions of source code must retain the above copyright
11  *       notice, this list of conditions and the following disclaimer.
12  *     * Redistributions in binary form must reproduce the above
13  *       copyright notice, this list of conditions and the following
14  *       disclaimer in the documentation and/or other materials
15  *       provided with the distribution.
16  *     * Neither the name of the "Oracle America, 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
21  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23  *   FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24  *   COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25  *   INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  *   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27  *   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28  *   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29  *   WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30  *   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 /*
34  * Copyright (c) 1986-1991 by Sun Microsystems Inc.
35  */
36 
37 /* #ident	"@(#)clnt_generic.c	1.20	94/05/03 SMI" */
38 
39 #include <sys/cdefs.h>
40 #if defined(LIBC_SCCS) && !defined(lint)
41 #if 0
42 static char sccsid[] = "@(#)clnt_generic.c 1.32 89/03/16 Copyr 1988 Sun Micro";
43 #else
44 __RCSID("$NetBSD: clnt_generic.c,v 1.33 2014/05/28 14:45:19 christos Exp $");
45 #endif
46 #endif
47 
48 #include "namespace.h"
49 #include "reentrant.h"
50 #include <sys/types.h>
51 #include <sys/socket.h>
52 #include <netinet/in.h>
53 #include <assert.h>
54 #include <stdio.h>
55 #include <errno.h>
56 #include <rpc/rpc.h>
57 #include <rpc/nettype.h>
58 #include <string.h>
59 #include <stdlib.h>
60 #include <unistd.h>
61 
62 #include "svc_fdset.h"
63 #include "rpc_internal.h"
64 
65 #ifdef __weak_alias
__weak_alias(clnt_create_vers,_clnt_create_vers)66 __weak_alias(clnt_create_vers,_clnt_create_vers)
67 __weak_alias(clnt_create,_clnt_create)
68 __weak_alias(clnt_tp_create,_clnt_tp_create)
69 __weak_alias(clnt_tli_create,_clnt_tli_create)
70 #endif
71 
72 /*
73  * Generic client creation with version checking the value of
74  * vers_out is set to the highest server supported value
75  * vers_low <= vers_out <= vers_high  AND an error results
76  * if this can not be done.
77  */
78 CLIENT *
79 clnt_create_vers(
80 	const char *	hostname,
81 	rpcprog_t	prog,
82 	rpcvers_t *	vers_out,
83 	rpcvers_t	vers_low,
84 	rpcvers_t	vers_high,
85 	const char *	nettype)
86 {
87 	CLIENT *clnt;
88 	struct timeval to;
89 	enum clnt_stat rpc_stat;
90 	struct rpc_err rpcerr;
91 
92 	_DIAGASSERT(hostname != NULL);
93 	_DIAGASSERT(vers_out != NULL);
94 	/* XXX: nettype appears to support being NULL */
95 
96 	clnt = clnt_create(hostname, prog, vers_high, nettype);
97 	if (clnt == NULL) {
98 		return (NULL);
99 	}
100 	to.tv_sec = 10;
101 	to.tv_usec = 0;
102 	rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
103 	    NULL, (xdrproc_t) xdr_void, NULL, to);
104 	if (rpc_stat == RPC_SUCCESS) {
105 		*vers_out = vers_high;
106 		return (clnt);
107 	}
108 	if (rpc_stat == RPC_PROGVERSMISMATCH) {
109 		unsigned long minvers, maxvers;
110 
111 		clnt_geterr(clnt, &rpcerr);
112 		minvers = rpcerr.re_vers.low;
113 		maxvers = rpcerr.re_vers.high;
114 		if (maxvers < vers_high)
115 			vers_high = (rpcvers_t)maxvers;
116 		if (minvers > vers_low)
117 			vers_low = (rpcvers_t)minvers;
118 		if (vers_low > vers_high) {
119 			goto error;
120 		}
121 		CLNT_CONTROL(clnt, CLSET_VERS, (char *)(void *)&vers_high);
122 		rpc_stat = clnt_call(clnt, NULLPROC, (xdrproc_t) xdr_void,
123 		    NULL, (xdrproc_t) xdr_void, NULL, to);
124 		if (rpc_stat == RPC_SUCCESS) {
125 			*vers_out = vers_high;
126 			return (clnt);
127 		}
128 	}
129 	clnt_geterr(clnt, &rpcerr);
130 
131 error:
132 	rpc_createerr.cf_stat = rpc_stat;
133 	rpc_createerr.cf_error = rpcerr;
134 	clnt_destroy(clnt);
135 	return (NULL);
136 }
137 
138 /*
139  * Top level client creation routine.
140  * Generic client creation: takes (servers name, program-number, nettype) and
141  * returns client handle. Default options are set, which the user can
142  * change using the rpc equivalent of ioctl()'s.
143  *
144  * It tries for all the netids in that particular class of netid until
145  * it succeeds.
146  * XXX The error message in the case of failure will be the one
147  * pertaining to the last create error.
148  *
149  * It calls clnt_tp_create();
150  */
151 CLIENT *
clnt_create(const char * hostname,rpcprog_t prog,rpcvers_t vers,const char * nettype)152 clnt_create(
153 	const char *	hostname,			/* server name */
154 	rpcprog_t	prog,				/* program number */
155 	rpcvers_t	vers,				/* version number */
156 	const char *	nettype)			/* net type */
157 {
158 	struct netconfig *nconf;
159 	CLIENT *clnt = NULL;
160 	void *handle;
161 	enum clnt_stat	save_cf_stat = RPC_SUCCESS;
162 	struct rpc_err	save_cf_error;
163 
164 	_DIAGASSERT(hostname != NULL);
165 	/* XXX: nettype appears to support being NULL */
166 
167 	if ((handle = __rpc_setconf(nettype)) == NULL) {
168 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
169 		return (NULL);
170 	}
171 	rpc_createerr.cf_stat = RPC_SUCCESS;
172 	while (clnt == NULL) {
173 		if ((nconf = __rpc_getconf(handle)) == NULL) {
174 			if (rpc_createerr.cf_stat == RPC_SUCCESS)
175 				rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
176 			break;
177 		}
178 #ifdef CLNT_DEBUG
179 		printf("trying netid %s\n", nconf->nc_netid);
180 #endif
181 		clnt = clnt_tp_create(hostname, prog, vers, nconf);
182 		if (clnt)
183 			break;
184 		else
185 			/*
186 			 *	Since we didn't get a name-to-address
187 			 *	translation failure here, we remember
188 			 *	this particular error.  The object of
189 			 *	this is to enable us to return to the
190 			 *	caller a more-specific error than the
191 			 *	unhelpful ``Name to address translation
192 			 *	failed'' which might well occur if we
193 			 *	merely returned the last error (because
194 			 *	the local loopbacks are typically the
195 			 *	last ones in /etc/netconfig and the most
196 			 *	likely to be unable to translate a host
197 			 *	name).
198 			 */
199 			if (rpc_createerr.cf_stat != RPC_N2AXLATEFAILURE) {
200 				save_cf_stat = rpc_createerr.cf_stat;
201 				save_cf_error = rpc_createerr.cf_error;
202 			}
203 	}
204 
205 	/*
206 	 *	Attempt to return an error more specific than ``Name to address
207 	 *	translation failed''
208 	 */
209 	if ((rpc_createerr.cf_stat == RPC_N2AXLATEFAILURE) &&
210 		(save_cf_stat != RPC_SUCCESS)) {
211 		rpc_createerr.cf_stat = save_cf_stat;
212 		rpc_createerr.cf_error = save_cf_error;
213 	}
214 	__rpc_endconf(handle);
215 	return (clnt);
216 }
217 
218 /*
219  * Generic client creation: takes (servers name, program-number, netconf) and
220  * returns client handle. Default options are set, which the user can
221  * change using the rpc equivalent of ioctl()'s : clnt_control()
222  * It finds out the server address from rpcbind and calls clnt_tli_create()
223  */
224 CLIENT *
clnt_tp_create(const char * hostname,rpcprog_t prog,rpcvers_t vers,const struct netconfig * nconf)225 clnt_tp_create(
226 	const char *		hostname,	/* server name */
227 	rpcprog_t		prog,		/* program number */
228 	rpcvers_t		vers,		/* version number */
229 	const struct netconfig *nconf)		/* net config struct */
230 {
231 	struct netbuf *svcaddr;			/* servers address */
232 	CLIENT *cl = NULL;			/* client handle */
233 
234 	_DIAGASSERT(hostname != NULL);
235 	/* nconf is handled below */
236 
237 	if (nconf == NULL) {
238 		rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
239 		return (NULL);
240 	}
241 
242 	/*
243 	 * Get the address of the server
244 	 */
245 	if ((svcaddr = __rpcb_findaddr(prog, vers, nconf, hostname,
246 		&cl)) == NULL) {
247 		/* appropriate error number is set by rpcbind libraries */
248 		return (NULL);
249 	}
250 	if (cl == NULL) {
251 		cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
252 					prog, vers, 0, 0);
253 	} else {
254 		/* Reuse the CLIENT handle and change the appropriate fields */
255 		if (CLNT_CONTROL(cl, CLSET_SVC_ADDR, (void *)svcaddr) == TRUE) {
256 			if (cl->cl_netid == NULL) {
257 				cl->cl_netid = strdup(nconf->nc_netid);
258 				if (cl->cl_netid == NULL)
259 					goto out;
260 			}
261 			if (cl->cl_tp == NULL) {
262 				cl->cl_tp = strdup(nconf->nc_device);
263 				if (cl->cl_tp == NULL)
264 					goto out;
265 			}
266 			(void) CLNT_CONTROL(cl, CLSET_PROG, (void *)&prog);
267 			(void) CLNT_CONTROL(cl, CLSET_VERS, (void *)&vers);
268 		} else {
269 			CLNT_DESTROY(cl);
270 			cl = clnt_tli_create(RPC_ANYFD, nconf, svcaddr,
271 					prog, vers, 0, 0);
272 		}
273 	}
274 	free(svcaddr->buf);
275 	free(svcaddr);
276 	return (cl);
277 out:
278 	clnt_destroy(cl);
279 	return NULL;
280 }
281 
282 /*
283  * Generic client creation:  returns client handle.
284  * Default options are set, which the user can
285  * change using the rpc equivalent of ioctl()'s : clnt_control().
286  * If fd is RPC_ANYFD, it will be opened using nconf.
287  * It will be bound if not so.
288  * If sizes are 0; appropriate defaults will be chosen.
289  */
290 CLIENT *
clnt_tli_create(int fd,const struct netconfig * nconf,const struct netbuf * svcaddr,rpcprog_t prog,rpcvers_t vers,u_int sendsz,u_int recvsz)291 clnt_tli_create(
292 	int fd,				/* fd */
293 	const struct netconfig *nconf,	/* netconfig structure */
294 	const struct netbuf *svcaddr,	/* servers address */
295 	rpcprog_t prog,			/* program number */
296 	rpcvers_t vers,			/* version number */
297 	u_int sendsz,			/* send size */
298 	u_int recvsz)			/* recv size */
299 {
300 	CLIENT *cl;			/* client handle */
301 	bool_t madefd = FALSE;		/* whether fd opened here */
302 	long servtype;
303 	struct __rpc_sockinfo si;
304 
305 	/* nconf is handled below */
306 	_DIAGASSERT(svcaddr != NULL);
307 
308 	if (fd == RPC_ANYFD) {
309 		if (nconf == NULL) {
310 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
311 			return (NULL);
312 		}
313 
314 		fd = __rpc_nconf2fd(nconf);
315 
316 		if (fd == -1)
317 			goto err;
318 
319 		madefd = TRUE;
320 		servtype = nconf->nc_semantics;
321 		if (!__rpc_fd2sockinfo(fd, &si))
322 			goto err;
323 
324 		(void)bindresvport(fd, NULL);
325 	} else {
326 		if (!__rpc_fd2sockinfo(fd, &si))
327 			goto err;
328 		servtype = __rpc_socktype2seman(si.si_socktype);
329 		if (servtype == -1) {
330 			rpc_createerr.cf_stat = RPC_UNKNOWNPROTO;
331 			return NULL;
332 		}
333 
334 	}
335 
336 	if (si.si_af != ((struct sockaddr *)svcaddr->buf)->sa_family) {
337 		rpc_createerr.cf_stat = RPC_UNKNOWNHOST;	/* XXX */
338 		goto err1;
339 	}
340 
341 	switch (servtype) {
342 	case NC_TPI_COTS_ORD:
343 		cl = clnt_vc_create(fd, svcaddr, prog, vers, sendsz, recvsz);
344 		if (!nconf || !cl)
345 			break;
346 		(void)__rpc_setnodelay(fd, &si);
347 		break;
348 	case NC_TPI_CLTS:
349 		cl = clnt_dg_create(fd, svcaddr, prog, vers, sendsz, recvsz);
350 		break;
351 	default:
352 		goto err;
353 	}
354 
355 	if (cl == NULL)
356 		goto err1; /* borrow errors from clnt_dg/vc creates */
357 	if (nconf) {
358 		cl->cl_netid = strdup(nconf->nc_netid);
359 		if (cl->cl_netid == NULL)
360 			goto err0;
361 		cl->cl_tp = strdup(nconf->nc_device);
362 		if (cl->cl_tp == NULL)
363 			goto err0;
364 	} else {
365 		cl->cl_netid = __UNCONST("");
366 		cl->cl_tp = __UNCONST("");
367 	}
368 	if (madefd) {
369 		(void) CLNT_CONTROL(cl, CLSET_FD_CLOSE, NULL);
370 /*		(void) CLNT_CONTROL(cl, CLSET_POP_TIMOD, NULL);  */
371 	};
372 
373 	return (cl);
374 
375 err0:
376 	clnt_destroy(cl);
377 err:
378 	rpc_createerr.cf_stat = RPC_SYSTEMERROR;
379 	rpc_createerr.cf_error.re_errno = errno;
380 err1:	if (madefd)
381 		(void) close(fd);
382 	return (NULL);
383 }
384 
385 /*
386  * Don't block thse so interactive programs don't get stuck in lalaland.
387  * (easier to do this than making connect(2) non-blocking..)
388  */
389 int
__clnt_sigfillset(sigset_t * ss)390 __clnt_sigfillset(sigset_t *ss) {
391 	static const int usersig[] = {
392 	    SIGHUP, SIGINT, SIGQUIT, SIGTERM, SIGTSTP
393 	};
394 	if (sigfillset(ss) == -1)
395 		return -1;
396 	for (size_t i = 0; i < __arraycount(usersig); i++)
397 		if (sigdelset(ss, usersig[i]) == -1)
398 			return -1;
399 	return 0;
400 }
401