xref: /illumos-gate/usr/src/stand/lib/fs/nfs/clnt_budp.c (revision 80ab886d)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /* Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
28 /* All Rights Reserved */
29 
30 /*
31  * Portions of this source code were derived from Berkeley 4.3 BSD
32  * under license from the Regents of the University of California.
33  */
34 
35 #pragma ident	"%Z%%M%	%I%	%E% SMI"
36 
37 /*
38  * Boot subsystem client side rpc
39  */
40 
41 #include <sys/errno.h>
42 #include <rpc/types.h>
43 #include <sys/socket.h>
44 #include <netinet/in.h>
45 #include "socket_inet.h"
46 #include "ipv4.h"
47 #include "clnt.h"
48 #include <rpc/rpc.h>
49 #include "brpc.h"
50 #include "pmap.h"
51 #include <sys/promif.h>
52 #include <rpc/xdr.h>
53 #include <rpc/auth.h>
54 #include <rpc/auth_sys.h>
55 #include "auth_inet.h"
56 #include <rpc/rpc_msg.h>
57 #include <sys/salib.h>
58 #include <sys/bootdebug.h>
59 
60 #define	dprintf if (boothowto & RB_DEBUG) printf
61 
62 /* retries to send RPC message when sendto fails */
63 #define	RPC_UDP_SEND_RETRIES	3
64 
65 extern int errno;
66 
67 /*
68  * If we create another clnt type this should be
69  * moved to a common file
70  */
71 struct rpc_createerr rpc_createerr;
72 
73 static struct clnt_ops *clntbudp_ops();
74 
75 /*
76  * Private data kept per client handle
77  */
78 struct cu_data {
79 	int		   cu_sock;
80 	bool_t		   cu_closeit;
81 	struct sockaddr_in cu_raddr;
82 	int		   cu_rlen;
83 	struct timeval	   cu_wait;
84 	struct timeval	   cu_total;
85 	struct rpc_err	   cu_error;
86 	XDR		   cu_outxdrs;
87 	uint_t		   cu_xdrpos;
88 	uint_t		   cu_sendsz;
89 	char		   *cu_outbuf;
90 	uint_t		   cu_recvsz;
91 	char		   cu_inbuf[1];
92 };
93 
94 /*
95  * Create a UDP based client handle.
96  * If *sockp<0, *sockp is set to a newly created UPD socket.
97  * If raddr->sin_port is 0 a binder on the remote machine
98  * is consulted for the correct port number.
99  * NB: It is the clients responsibility to close *sockp.
100  * NB: The rpch->cl_auth is initialized to null authentication.
101  *	Caller may wish to set this something more useful.
102  *
103  * wait is the amount of time used between retransmitting a call if
104  * no response has been heard;  retransmition occurs until the actual
105  * rpc call times out.
106  *
107  * sendsz and recvsz are the maximum allowable packet sizes that can be
108  * sent and received.
109  */
110 CLIENT *
111 clntbudp_bufcreate(raddr, program, version, wait, sockp, sendsz, recvsz)
112 	struct sockaddr_in *raddr;
113 	rpcprog_t program;
114 	rpcvers_t version;
115 	struct timeval wait;
116 	int *sockp;
117 	uint_t sendsz;
118 	uint_t recvsz;
119 {
120 	CLIENT *cl;
121 	struct cu_data *cu;
122 	struct rpc_msg call_msg;
123 
124 	cl = (CLIENT *)bkmem_alloc(sizeof (CLIENT));
125 	if (cl == NULL) {
126 		errno = ENOMEM;
127 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
128 		rpc_createerr.cf_error.re_errno = errno;
129 		return ((CLIENT *)NULL);
130 	}
131 	sendsz = ((sendsz + 3) / 4) * 4;
132 	recvsz = ((recvsz + 3) / 4) * 4;
133 	cu = (struct cu_data *)bkmem_alloc(sizeof (*cu) + sendsz + recvsz);
134 	if (cu == NULL) {
135 		errno = ENOMEM;
136 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
137 		rpc_createerr.cf_error.re_errno = errno;
138 		goto fooy;
139 	}
140 	cu->cu_outbuf = &cu->cu_inbuf[recvsz];
141 
142 	if (raddr->sin_port == 0) {
143 		ushort_t port;
144 		if ((port = bpmap_getport(program, version,
145 				&(rpc_createerr.cf_stat), raddr, NULL)) == 0) {
146 			goto fooy;
147 		}
148 		raddr->sin_port = htons(port);
149 	}
150 	cl->cl_ops = clntbudp_ops();
151 	cl->cl_private = (caddr_t)cu;
152 	cu->cu_raddr = *raddr;
153 	cu->cu_rlen = sizeof (cu->cu_raddr);
154 	cu->cu_wait = wait;
155 	cu->cu_total.tv_sec = -1;
156 	cu->cu_total.tv_usec = -1;
157 	cu->cu_sendsz = sendsz;
158 	cu->cu_recvsz = recvsz;
159 	call_msg.rm_xid = (uint_t)prom_gettime() + 1;
160 	call_msg.rm_direction = CALL;
161 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
162 	call_msg.rm_call.cb_prog = program;
163 	call_msg.rm_call.cb_vers = version;
164 	xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
165 	    sendsz, XDR_ENCODE);
166 	if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
167 		goto fooy;
168 	}
169 	cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
170 	cu->cu_closeit = FALSE;
171 
172 	if (*sockp < 0) {
173 		struct sockaddr_in from;
174 
175 		*sockp = socket(PF_INET, SOCK_DGRAM, 0);
176 		if (*sockp < 0) {
177 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
178 			rpc_createerr.cf_error.re_errno = errno;
179 			goto fooy;
180 		}
181 
182 		if (dontroute) {
183 			(void) setsockopt(*sockp, SOL_SOCKET, SO_DONTROUTE,
184 				(const void *)&dontroute, sizeof (dontroute));
185 		}
186 
187 		/* attempt to bind to priv port */
188 		from.sin_family = AF_INET;
189 		ipv4_getipaddr(&from.sin_addr);
190 		from.sin_addr.s_addr = htonl(from.sin_addr.s_addr);
191 		from.sin_port = get_source_port(TRUE);
192 
193 		if (bind(*sockp, (struct sockaddr *)&from, sizeof (from)) < 0) {
194 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
195 			rpc_createerr.cf_error.re_errno = errno;
196 			goto fooy;
197 		}
198 
199 		cu->cu_closeit = TRUE;
200 	}
201 
202 	cu->cu_sock = *sockp;
203 	cl->cl_auth = authnone_create();
204 	return (cl);
205 fooy:
206 	if (cu)
207 		bkmem_free((caddr_t)cu, sizeof (*cu) + sendsz + recvsz);
208 	if (cl)
209 		bkmem_free((caddr_t)cl, sizeof (CLIENT));
210 	return ((CLIENT *)NULL);
211 }
212 
213 CLIENT *
214 clntbudp_create(raddr, program, version, wait, sockp)
215 	struct sockaddr_in *raddr;
216 	rpcprog_t program;
217 	rpcvers_t version;
218 	struct timeval wait;
219 	int *sockp;
220 {
221 
222 	return (clntbudp_bufcreate(raddr, program, version, wait, sockp,
223 	    UDPMSGSIZE, UDPMSGSIZE));
224 }
225 
226 static enum clnt_stat
227 clntbudp_call(cl, proc, xargs, argsp, xresults, resultsp, utimeout)
228 	CLIENT		*cl;		/* client handle */
229 	rpcproc_t	proc;		/* procedure number */
230 	xdrproc_t	xargs;		/* xdr routine for args */
231 	caddr_t		argsp;		/* pointer to args */
232 	xdrproc_t	xresults;	/* xdr routine for results */
233 	caddr_t		resultsp;	/* pointer to results */
234 	struct timeval	utimeout;	/* seconds to wait before giving up */
235 {
236 	struct cu_data *cu;
237 	XDR *xdrs;
238 	int outlen;
239 	int inlen;
240 	socklen_t fromlen;
241 	struct sockaddr_in from;
242 	struct rpc_msg reply_msg;
243 	XDR reply_xdrs;
244 	uint_t xdelay;
245 	int wait_time;
246 	bool_t ok;
247 	int nrefreshes = 2;	/* number of times to refresh cred */
248 	struct timeval timeout;
249 	int errors;
250 	short send_retries = RPC_UDP_SEND_RETRIES;
251 
252 	cu = (struct cu_data *)cl->cl_private;
253 	if (cu->cu_total.tv_usec == -1)
254 		timeout = utimeout;	/* use supplied timeout */
255 	else
256 		timeout = cu->cu_total; /* use default timeout */
257 
258 	/*
259 	 * set a media level timeout
260 	 */
261 	xdelay = cu->cu_wait.tv_sec + 1000 + cu->cu_wait.tv_usec / 1000;
262 	(void) setsockopt(cu->cu_sock, SOL_SOCKET, SO_RCVTIMEO,
263 				(void *)&xdelay, sizeof (xdelay));
264 
265 	wait_time = (timeout.tv_sec * 1000) + (timeout.tv_usec / 1000);
266 	if (wait_time == 0)
267 		wait_time = RPC_RCVWAIT_MSEC;
268 	wait_time += prom_gettime();
269 
270 	errors = 0;
271 
272 call_again:
273 	xdrs = &(cu->cu_outxdrs);
274 	xdrs->x_op = XDR_ENCODE;
275 	XDR_SETPOS(xdrs, cu->cu_xdrpos);
276 	/*
277 	 * the transaction is the first thing in the out buffer
278 	 */
279 	(*(ushort_t *)(cu->cu_outbuf))++;
280 	if ((! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
281 	    (! AUTH_MARSHALL(cl->cl_auth, xdrs, NULL)) ||
282 	    (! (*xargs)(xdrs, argsp)))
283 		return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
284 	outlen = (int)XDR_GETPOS(xdrs);
285 
286 send_again:
287 	if (sendto(cu->cu_sock, cu->cu_outbuf, outlen, 0,
288 	    (struct sockaddr *)&(cu->cu_raddr), cu->cu_rlen)
289 	    != outlen) {
290 		if (errno == ETIMEDOUT) {
291 			/*
292 			 * sendto() times out probably because
293 			 * ARP times out while waiting for reply.
294 			 * We retry sending RPC message again.
295 			 */
296 			if (send_retries-- > 0) {
297 				dprintf("clntbudp_call: timedout, try sending"
298 				    "RPC again\n");
299 				errno = 0;
300 				goto send_again;
301 			}
302 			cu->cu_error.re_status = RPC_TIMEDOUT;
303 		} else {
304 			cu->cu_error.re_status = RPC_CANTSEND;
305 		}
306 		cu->cu_error.re_errno = errno;
307 		return (cu->cu_error.re_status);
308 	}
309 
310 	/*
311 	 * sub-optimal code appears here because we have
312 	 * some clock time to spare while the packets are in flight.
313 	 * (We assume that this is actually only executed once.)
314 	 */
315 recv_again:
316 	reply_msg.acpted_rply.ar_verf = _null_auth;
317 	reply_msg.acpted_rply.ar_results.where = resultsp;
318 	reply_msg.acpted_rply.ar_results.proc = xresults;
319 
320 	for (;;) {
321 		if (errors >= RPC_ALLOWABLE_ERRORS)
322 			return (cu->cu_error.re_status);
323 
324 		if (prom_gettime() >= wait_time) {
325 			cu->cu_error.re_errno = ETIMEDOUT;
326 			return (cu->cu_error.re_status = RPC_TIMEDOUT);
327 		}
328 
329 		/*
330 		 * Use MSG_DONTWAIT because we have set
331 		 * a media level timeout above.
332 		 */
333 		fromlen = sizeof (struct sockaddr);
334 
335 		inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
336 				(int)cu->cu_recvsz, MSG_DONTWAIT,
337 				(struct sockaddr *)&from, &fromlen);
338 
339 		if (inlen < 0) {
340 			if (errno == EWOULDBLOCK) {
341 				/*
342 				 * Media level has timedout
343 				 * and no more data in buffers.
344 				 */
345 				goto send_again;
346 			}
347 
348 			cu->cu_error.re_status = RPC_CANTRECV;
349 			if (errno == ETIMEDOUT) {
350 				errno = ETIMEDOUT;
351 				cu->cu_error.re_status = RPC_TIMEDOUT;
352 			}
353 
354 			cu->cu_error.re_errno = errno;
355 			return (cu->cu_error.re_status);
356 		}
357 
358 		if (inlen < sizeof (uint32_t))
359 			continue;
360 
361 		/* see if reply transaction id matches sent id */
362 		if (*((uint32_t *)(cu->cu_inbuf)) !=
363 				*((uint32_t *)(cu->cu_outbuf))) {
364 			dprintf("clntbudp_call: xid: 0x%x != 0x%x\n",
365 				*(uint32_t *)(cu->cu_inbuf),
366 				*(uint32_t *)(cu->cu_outbuf));
367 			continue;
368 		}
369 		/* we now assume we have the proper reply */
370 		break;
371 	}
372 
373 	/*
374 	 * now decode and validate the response
375 	 */
376 	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (uint_t)inlen, XDR_DECODE);
377 	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
378 	/* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
379 	if (!ok) {
380 		cu->cu_error.re_status = RPC_CANTDECODERES;
381 		return (cu->cu_error.re_status);
382 	}
383 
384 	_seterr_reply(&reply_msg, &(cu->cu_error));
385 	if (cu->cu_error.re_status == RPC_SUCCESS) {
386 		if (! AUTH_VALIDATE(cl->cl_auth,
387 			&reply_msg.acpted_rply.ar_verf)) {
388 			cu->cu_error.re_status = RPC_AUTHERROR;
389 			cu->cu_error.re_why = AUTH_INVALIDRESP;
390 			errors++;
391 			goto call_again;
392 		}
393 		if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
394 			xdrs->x_op = XDR_FREE;
395 			(void) xdr_opaque_auth(xdrs,
396 			    &(reply_msg.acpted_rply.ar_verf));
397 		}
398 		return (cu->cu_error.re_status);
399 	}  /* end successful completion */
400 
401 	if (cu->cu_error.re_status == RPC_AUTHERROR) {
402 		/* maybe our credentials need to be refreshed ... */
403 		if (nrefreshes > 0 &&
404 			AUTH_REFRESH(cl->cl_auth, NULL, NULL)) {
405 			nrefreshes--;
406 		}
407 		errors++;
408 		goto call_again;
409 	}
410 
411 	/* Just keep trying till there's no data... */
412 	errors++;
413 	dprintf("clntbudp_call: from: %s, error: ",
414 		inet_ntoa(from.sin_addr));
415 	rpc_disperr(&cu->cu_error);
416 	goto recv_again;
417 }
418 
419 static void
420 clntbudp_geterr(cl, errp)
421 	CLIENT *cl;
422 	struct rpc_err *errp;
423 {
424 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
425 
426 	*errp = cu->cu_error;
427 }
428 
429 
430 static bool_t
431 clntbudp_freeres(cl, xdr_res, res_ptr)
432 	CLIENT *cl;
433 	xdrproc_t xdr_res;
434 	caddr_t res_ptr;
435 {
436 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
437 	XDR *xdrs = &(cu->cu_outxdrs);
438 
439 	xdrs->x_op = XDR_FREE;
440 	return ((*xdr_res)(xdrs, res_ptr));
441 }
442 
443 static void
444 clntbudp_abort()
445 	/* CLIENT *h; */
446 {
447 }
448 
449 /* ARGSUSED */
450 static bool_t
451 clntbudp_control(cl, request, info)
452 	CLIENT *cl;
453 	int request;
454 	char *info;
455 {
456 	/* CLNT_CONTROL is not used in boot */
457 	return (FALSE);
458 }
459 
460 static void
461 clntbudp_destroy(cl)
462 	CLIENT *cl;
463 {
464 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
465 
466 	if (cu->cu_closeit) {
467 		(void) socket_close(cu->cu_sock);
468 	}
469 	XDR_DESTROY(&(cu->cu_outxdrs));
470 	bkmem_free((caddr_t)cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
471 	bkmem_free((caddr_t)cl, sizeof (CLIENT));
472 }
473 
474 static struct clnt_ops *
475 clntbudp_ops()
476 {
477 	static struct clnt_ops ops;
478 
479 	if (ops.cl_call == NULL) {
480 		ops.cl_call = clntbudp_call;
481 		ops.cl_abort = clntbudp_abort;
482 		ops.cl_geterr = clntbudp_geterr;
483 		ops.cl_freeres = clntbudp_freeres;
484 		ops.cl_destroy = clntbudp_destroy;
485 		ops.cl_control = clntbudp_control;
486 	}
487 	return (&ops);
488 }
489