1 /* @(#)clnt_udp.c	2.2 88/08/01 4.0 RPCSRC */
2 /*
3  * Copyright (c) 2010, Oracle America, Inc.
4  *
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are met:
9  *
10  *     * Redistributions of source code must retain the above copyright
11  *       notice, this list of conditions and the following disclaimer.
12  *
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *
18  *     * Neither the name of the "Oracle America, Inc." nor the names of
19  *       its contributors may be used to endorse or promote products
20  *       derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
23  * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
24  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
25  * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
26  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
28  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
29  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
30  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
31  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
32  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 #if !defined(lint) && defined(SCCSIDS)
35 static char sccsid[] = "@(#)clnt_udp.c 1.39 87/08/11 Copyr 1984 Sun Micro";
36 #endif
37 
38 /*
39  * clnt_udp.c, Implements a UDP/IP based, client side RPC.
40  */
41 
42 #include <stdio.h>
43 #include <unistd.h>
44 #include <gssrpc/rpc.h>
45 #include <sys/socket.h>
46 #include <sys/ioctl.h>
47 #if defined(sun)
48 #include <sys/filio.h>
49 #endif
50 #include <netdb.h>
51 #include <errno.h>
52 #include <string.h>
53 #include <gssrpc/pmap_clnt.h>
54 #include <port-sockets.h>
55 #include <errno.h>
56 
57 #ifndef GETSOCKNAME_ARG3_TYPE
58 #define GETSOCKNAME_ARG3_TYPE int
59 #endif
60 
61 /*
62  * UDP bases client side rpc operations
63  */
64 static enum clnt_stat	clntudp_call(CLIENT *, rpcproc_t, xdrproc_t, void *,
65 				     xdrproc_t, void *, struct timeval);
66 static void		clntudp_abort(CLIENT *);
67 static void		clntudp_geterr(CLIENT *, struct rpc_err *);
68 static bool_t		clntudp_freeres(CLIENT *, xdrproc_t, void *);
69 static bool_t           clntudp_control(CLIENT *, int, void *);
70 static void		clntudp_destroy(CLIENT *);
71 
72 static struct clnt_ops udp_ops = {
73 	clntudp_call,
74 	clntudp_abort,
75 	clntudp_geterr,
76 	clntudp_freeres,
77 	clntudp_destroy,
78 	clntudp_control
79 };
80 
81 /*
82  * Private data kept per client handle
83  */
84 struct cu_data {
85         SOCKET             cu_sock;
86 	bool_t		   cu_closeit;
87 	struct sockaddr_in cu_raddr;
88 	int		   cu_rlen;
89 	struct sockaddr_in cu_laddr;
90         GETSOCKNAME_ARG3_TYPE  cu_llen;
91 	struct timeval	   cu_wait;
92 	struct timeval     cu_total;
93 	struct rpc_err	   cu_error;
94 	XDR		   cu_outxdrs;
95 	u_int		   cu_xdrpos;
96 	u_int		   cu_sendsz;
97 	char		   *cu_outbuf;
98 	u_int		   cu_recvsz;
99 	char		   cu_inbuf[1];
100 };
101 
102 /*
103  * Create a UDP based client handle.
104  * If *sockp<0, *sockp is set to a newly created UPD socket.
105  * If raddr->sin_port is 0 a binder on the remote machine
106  * is consulted for the correct port number.
107  * NB: It is the clients responsibility to close *sockp.
108  * NB: The rpch->cl_auth is initialized to null authentication.
109  *     Caller may wish to set this something more useful.
110  *
111  * wait is the amount of time used between retransmitting a call if
112  * no response has been heard;  retransmission occurs until the actual
113  * rpc call times out.
114  *
115  * sendsz and recvsz are the maximum allowable packet sizes that can be
116  * sent and received.
117  */
118 CLIENT *
clntudp_bufcreate(struct sockaddr_in * raddr,rpcprog_t program,rpcvers_t version,struct timeval wait,int * sockp,u_int sendsz,u_int recvsz)119 clntudp_bufcreate(
120 	struct sockaddr_in *raddr,
121 	rpcprog_t program,
122 	rpcvers_t version,
123 	struct timeval wait,
124 	int *sockp,
125 	u_int sendsz,
126 	u_int recvsz)
127 {
128 	CLIENT *cl;
129 	struct cu_data *cu = 0;
130 	struct timeval now;
131 	struct rpc_msg call_msg;
132 
133 	cl = (CLIENT *)mem_alloc(sizeof(CLIENT));
134 	if (cl == NULL) {
135 		(void) fprintf(stderr, "clntudp_create: out of memory\n");
136 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
137 		rpc_createerr.cf_error.re_errno = errno;
138 		goto fooy;
139 	}
140 	sendsz = ((sendsz + 3) / 4) * 4;
141 	recvsz = ((recvsz + 3) / 4) * 4;
142 	cu = (struct cu_data *)mem_alloc(sizeof(*cu) + sendsz + recvsz);
143 	if (cu == NULL) {
144 		(void) fprintf(stderr, "clntudp_create: out of memory\n");
145 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
146 		rpc_createerr.cf_error.re_errno = errno;
147 		goto fooy;
148 	}
149 	cu->cu_outbuf = &cu->cu_inbuf[recvsz];
150 
151 	(void)gettimeofday(&now, (struct timezone *)0);
152 	if (raddr->sin_port == 0) {
153 		u_short port;
154 		if ((port =
155 		    pmap_getport(raddr, program, version, IPPROTO_UDP)) == 0) {
156 			goto fooy;
157 		}
158 		raddr->sin_port = htons(port);
159 	}
160 	cl->cl_ops = &udp_ops;
161 	cl->cl_private = (caddr_t)cu;
162 	cu->cu_raddr = *raddr;
163 	cu->cu_rlen = sizeof (cu->cu_raddr);
164 	cu->cu_wait = wait;
165 	cu->cu_total.tv_sec = -1;
166 	cu->cu_total.tv_usec = -1;
167 	cu->cu_sendsz = sendsz;
168 	cu->cu_recvsz = recvsz;
169 	call_msg.rm_xid = getpid() ^ now.tv_sec ^ now.tv_usec;
170 	call_msg.rm_direction = CALL;
171 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
172 	call_msg.rm_call.cb_prog = program;
173 	call_msg.rm_call.cb_vers = version;
174 	xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
175 	    sendsz, XDR_ENCODE);
176 	if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
177 		goto fooy;
178 	}
179 	cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
180 	if (*sockp < 0) {
181 		int dontblock = 1;
182 
183 		*sockp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
184 		if (*sockp < 0) {
185 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
186 			rpc_createerr.cf_error.re_errno = errno;
187 			goto fooy;
188 		}
189 		/* attempt to bind to prov port */
190 		(void)bindresvport_sa(*sockp, NULL);
191 		/* the sockets rpc controls are non-blocking */
192 		(void)ioctl(*sockp, FIONBIO, (char *) &dontblock);
193 		cu->cu_closeit = TRUE;
194 	} else {
195 		cu->cu_closeit = FALSE;
196 	}
197 	if (connect(*sockp, (struct sockaddr *)raddr, sizeof(*raddr)) < 0)
198 	     goto fooy;
199 	cu->cu_llen = sizeof(cu->cu_laddr);
200 	if (getsockname(*sockp, (struct sockaddr *)&cu->cu_laddr, &cu->cu_llen) < 0)
201 	     goto fooy;
202 
203 	cu->cu_sock = *sockp;
204 	cl->cl_auth = authnone_create();
205 	return (cl);
206 fooy:
207 	if (cu)
208 		mem_free((caddr_t)cu, sizeof(*cu) + sendsz + recvsz);
209 	if (cl)
210 		mem_free((caddr_t)cl, sizeof(CLIENT));
211 	return ((CLIENT *)NULL);
212 }
213 
214 CLIENT *
clntudp_create(struct sockaddr_in * raddr,rpcprog_t program,rpcvers_t version,struct timeval wait,int * sockp)215 clntudp_create(
216 	struct sockaddr_in *raddr,
217 	rpcprog_t program,
218 	rpcvers_t version,
219 	struct timeval wait,
220 	int *sockp)
221 {
222 
223 	return(clntudp_bufcreate(raddr, program, version, wait, sockp,
224 	    UDPMSGSIZE, UDPMSGSIZE));
225 }
226 
227 static enum clnt_stat
clntudp_call(CLIENT * cl,rpcproc_t proc,xdrproc_t xargs,void * argsp,xdrproc_t xresults,void * resultsp,struct timeval utimeout)228 clntudp_call(
229 	CLIENT	*cl,			/* client handle */
230 	rpcproc_t	proc,		/* procedure number */
231 	xdrproc_t	xargs,		/* xdr routine for args */
232 	void *		argsp,		/* pointer to args */
233 	xdrproc_t	xresults,	/* xdr routine for results */
234 	void *		resultsp,	/* pointer to results */
235 	struct timeval	utimeout	/* seconds to wait before
236 					 * giving up */
237 	)
238 {
239 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
240 	XDR *xdrs;
241 	int outlen;
242 	ssize_t inlen;
243 	GETSOCKNAME_ARG3_TYPE fromlen; /* Assumes recvfrom uses same type */
244 #ifdef FD_SETSIZE
245 	fd_set readfds;
246 	fd_set mask;
247 #else
248 	int readfds;
249 	int mask;
250 #endif /* def FD_SETSIZE */
251 	struct sockaddr_in from;
252 	struct rpc_msg reply_msg;
253 	XDR reply_xdrs;
254 	struct timeval time_waited, seltimeout;
255 	bool_t ok;
256 	int nrefreshes = 2;	/* number of times to refresh cred */
257 	struct timeval timeout;
258 	long procl = proc;
259 
260 	if (cu->cu_total.tv_usec == -1) {
261 		timeout = utimeout;     /* use supplied timeout */
262 	} else {
263 		timeout = cu->cu_total; /* use default timeout */
264 	}
265 
266 	time_waited.tv_sec = 0;
267 	time_waited.tv_usec = 0;
268 call_again:
269 	xdrs = &(cu->cu_outxdrs);
270 	xdrs->x_op = XDR_ENCODE;
271 	XDR_SETPOS(xdrs, cu->cu_xdrpos);
272 	/*
273 	 * the transaction is the first thing in the out buffer
274 	 */
275 	(*(uint32_t *)(void *)(cu->cu_outbuf))++;
276 	if ((! XDR_PUTLONG(xdrs, &procl)) ||
277 	    (! AUTH_MARSHALL(cl->cl_auth, xdrs)) ||
278 	    (! AUTH_WRAP(cl->cl_auth, xdrs, xargs, argsp)))
279 		return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
280 	outlen = (int)XDR_GETPOS(xdrs);
281 
282 send_again:
283 	if (send(cu->cu_sock, cu->cu_outbuf, (u_int)outlen, 0) != outlen) {
284 		cu->cu_error.re_errno = errno;
285 		return (cu->cu_error.re_status = RPC_CANTSEND);
286 	}
287 
288 	/*
289 	 * Hack to provide rpc-based message passing
290 	 */
291 	if (timeout.tv_sec == 0 && timeout.tv_usec == 0) {
292 		return (cu->cu_error.re_status = RPC_TIMEDOUT);
293 	}
294 	/*
295 	 * sub-optimal code appears here because we have
296 	 * some clock time to spare while the packets are in flight.
297 	 * (We assume that this is actually only executed once.)
298 	 */
299 	reply_msg.acpted_rply.ar_verf = gssrpc__null_auth;
300 	reply_msg.acpted_rply.ar_results.where = NULL;
301 	reply_msg.acpted_rply.ar_results.proc = xdr_void;
302 #ifdef FD_SETSIZE
303 	FD_ZERO(&mask);
304 	FD_SET(cu->cu_sock, &mask);
305 #else
306 	mask = 1 << cu->cu_sock;
307 #endif /* def FD_SETSIZE */
308 	for (;;) {
309 		readfds = mask;
310 		seltimeout = cu->cu_wait;
311 		switch (select(gssrpc__rpc_dtablesize(), &readfds, (fd_set *)NULL,
312 			       (fd_set *)NULL, &seltimeout)) {
313 
314 		case 0:
315 			time_waited.tv_sec += cu->cu_wait.tv_sec;
316 			time_waited.tv_usec += cu->cu_wait.tv_usec;
317 			while (time_waited.tv_usec >= 1000000) {
318 				time_waited.tv_sec++;
319 				time_waited.tv_usec -= 1000000;
320 			}
321 			if ((time_waited.tv_sec < timeout.tv_sec) ||
322 				((time_waited.tv_sec == timeout.tv_sec) &&
323 				(time_waited.tv_usec < timeout.tv_usec)))
324 				goto send_again;
325 			return (cu->cu_error.re_status = RPC_TIMEDOUT);
326 
327 		/*
328 		 * buggy in other cases because time_waited is not being
329 		 * updated.
330 		 */
331 		case -1:
332 			if (errno == EINTR)
333 				continue;
334 			cu->cu_error.re_errno = errno;
335 			return (cu->cu_error.re_status = RPC_CANTRECV);
336 		}
337 		do {
338 			fromlen = sizeof(struct sockaddr);
339 			inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
340 				cu->cu_recvsz, 0,
341 				(struct sockaddr *)&from, &fromlen);
342 		} while (inlen < 0 && errno == EINTR);
343 		if (inlen < 0) {
344 			if (errno == EWOULDBLOCK)
345 				continue;
346 			cu->cu_error.re_errno = errno;
347 			return (cu->cu_error.re_status = RPC_CANTRECV);
348 		}
349 		if ((size_t)inlen < sizeof(uint32_t))
350 			continue;
351 		/* see if reply transaction id matches sent id */
352 		if (*((uint32_t *)(void *)(cu->cu_inbuf)) !=
353 		    *((uint32_t *)(void *)(cu->cu_outbuf)))
354 			continue;
355 		/* we now assume we have the proper reply */
356 		break;
357 	}
358 
359 	/*
360 	 * now decode and validate the response
361 	 */
362 	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (u_int)inlen, XDR_DECODE);
363 	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
364 	/* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
365 	if (ok) {
366 		gssrpc__seterr_reply(&reply_msg, &(cu->cu_error));
367 		if (cu->cu_error.re_status == RPC_SUCCESS) {
368 			if (! AUTH_VALIDATE(cl->cl_auth,
369 				&reply_msg.acpted_rply.ar_verf)) {
370 				cu->cu_error.re_status = RPC_AUTHERROR;
371 				cu->cu_error.re_why = AUTH_INVALIDRESP;
372 			} else if (! AUTH_UNWRAP(cl->cl_auth, &reply_xdrs,
373 						 xresults, resultsp)) {
374 			     if (cu->cu_error.re_status == RPC_SUCCESS)
375 				  cu->cu_error.re_status = RPC_CANTDECODERES;
376 			}
377 		}  /* end successful completion */
378 		else {
379 			/* maybe our credentials need to be refreshed ... */
380 			if (nrefreshes > 0 &&
381 			    AUTH_REFRESH(cl->cl_auth, &reply_msg)) {
382 				nrefreshes--;
383 				goto call_again;
384 			}
385 		}  /* end of unsuccessful completion */
386 		/* free verifier */
387 		if ((reply_msg.rm_reply.rp_stat == MSG_ACCEPTED) &&
388 		    (reply_msg.acpted_rply.ar_verf.oa_base != NULL)) {
389 		    xdrs->x_op = XDR_FREE;
390 		    (void)xdr_opaque_auth(xdrs,
391 					  &(reply_msg.acpted_rply.ar_verf));
392 		}
393 	}  /* end of valid reply message */
394 	else {
395 		/*
396 		 * It's possible for xdr_replymsg() to fail partway
397 		 * through its attempt to decode the result from the
398 		 * server. If this happens, it will leave the reply
399 		 * structure partially populated with dynamically
400 		 * allocated memory. (This can happen if someone uses
401 		 * clntudp_bufcreate() to create a CLIENT handle and
402 		 * specifies a receive buffer size that is too small.)
403 		 * This memory must be free()ed to avoid a leak.
404 		 */
405 		enum xdr_op op = reply_xdrs.x_op;
406 		reply_xdrs.x_op = XDR_FREE;
407 		xdr_replymsg(&reply_xdrs, &reply_msg);
408 		reply_xdrs.x_op = op;
409 		cu->cu_error.re_status = RPC_CANTDECODERES;
410 	}
411 	return (cu->cu_error.re_status);
412 }
413 
414 static void
clntudp_geterr(CLIENT * cl,struct rpc_err * errp)415 clntudp_geterr(
416 	CLIENT *cl,
417 	struct rpc_err *errp)
418 {
419 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
420 
421 	*errp = cu->cu_error;
422 }
423 
424 
425 static bool_t
clntudp_freeres(CLIENT * cl,xdrproc_t xdr_res,void * res_ptr)426 clntudp_freeres(
427 	CLIENT *cl,
428 	xdrproc_t xdr_res,
429 	void *res_ptr)
430 {
431 	struct cu_data *cu = cl->cl_private;
432 	XDR *xdrs = &cu->cu_outxdrs;
433 
434 	xdrs->x_op = XDR_FREE;
435 	return ((*xdr_res)(xdrs, res_ptr));
436 }
437 
438 
439 /*ARGSUSED*/
440 static void
clntudp_abort(CLIENT * h)441 clntudp_abort(CLIENT *h)
442 {
443 }
444 
445 static bool_t
clntudp_control(CLIENT * cl,int request,void * info)446 clntudp_control(
447 	CLIENT *cl,
448 	int request,
449 	void *info)
450 {
451 	struct cu_data *cu = cl->cl_private;
452 
453 	switch (request) {
454 	case CLSET_TIMEOUT:
455 		cu->cu_total = *(struct timeval *)info;
456 		break;
457 	case CLGET_TIMEOUT:
458 		*(struct timeval *)info = cu->cu_total;
459 		break;
460 	case CLSET_RETRY_TIMEOUT:
461 		cu->cu_wait = *(struct timeval *)info;
462 		break;
463 	case CLGET_RETRY_TIMEOUT:
464 		*(struct timeval *)info = cu->cu_wait;
465 		break;
466 	case CLGET_SERVER_ADDR:
467 		*(struct sockaddr_in *)info = cu->cu_raddr;
468 		break;
469 	case CLGET_LOCAL_ADDR:
470 		*(struct sockaddr_in *)info = cu->cu_laddr;
471 		break;
472 	default:
473 		return (FALSE);
474 	}
475 	return (TRUE);
476 }
477 
478 static void
clntudp_destroy(CLIENT * cl)479 clntudp_destroy(CLIENT *cl)
480 {
481 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
482 
483 	if (cu->cu_closeit)
484                 (void)closesocket(cu->cu_sock);
485 	XDR_DESTROY(&(cu->cu_outxdrs));
486 	mem_free((caddr_t)cu, (sizeof(*cu) + cu->cu_sendsz + cu->cu_recvsz));
487 	mem_free((caddr_t)cl, sizeof(CLIENT));
488 }
489