xref: /illumos-gate/usr/src/stand/lib/fs/nfs/clnt_budp.c (revision 7b34a9a5df26271af0da06974fc361c468cd48d3)
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 /*
36  * Boot subsystem client side rpc
37  */
38 
39 #include <sys/errno.h>
40 #include <rpc/types.h>
41 #include <sys/socket.h>
42 #include <netinet/in.h>
43 #include "socket_inet.h"
44 #include "ipv4.h"
45 #include "clnt.h"
46 #include <rpc/rpc.h>
47 #include "brpc.h"
48 #include "pmap.h"
49 #include <sys/promif.h>
50 #include <rpc/xdr.h>
51 #include <rpc/auth.h>
52 #include <rpc/auth_sys.h>
53 #include "auth_inet.h"
54 #include <rpc/rpc_msg.h>
55 #include <sys/salib.h>
56 #include <sys/bootdebug.h>
57 
58 #define	dprintf if (boothowto & RB_DEBUG) printf
59 
60 /* retries to send RPC message when sendto fails */
61 #define	RPC_UDP_SEND_RETRIES	3
62 
63 extern int errno;
64 
65 /*
66  * If we create another clnt type this should be
67  * moved to a common file
68  */
69 struct rpc_createerr rpc_createerr;
70 
71 static struct clnt_ops *clntbudp_ops();
72 
73 /*
74  * Private data kept per client handle
75  */
76 struct cu_data {
77 	int		   cu_sock;
78 	bool_t		   cu_closeit;
79 	struct sockaddr_in cu_raddr;
80 	int		   cu_rlen;
81 	struct timeval	   cu_wait;
82 	struct timeval	   cu_total;
83 	struct rpc_err	   cu_error;
84 	XDR		   cu_outxdrs;
85 	uint_t		   cu_xdrpos;
86 	uint_t		   cu_sendsz;
87 	char		   *cu_outbuf;
88 	uint_t		   cu_recvsz;
89 	char		   cu_inbuf[1];
90 };
91 
92 /*
93  * Create a UDP based client handle.
94  * If *sockp<0, *sockp is set to a newly created UPD socket.
95  * If raddr->sin_port is 0 a binder on the remote machine
96  * is consulted for the correct port number.
97  * NB: It is the clients responsibility to close *sockp.
98  * NB: The rpch->cl_auth is initialized to null authentication.
99  *	Caller may wish to set this something more useful.
100  *
101  * wait is the amount of time used between retransmitting a call if
102  * no response has been heard;  retransmition occurs until the actual
103  * rpc call times out.
104  *
105  * sendsz and recvsz are the maximum allowable packet sizes that can be
106  * sent and received.
107  */
108 CLIENT *
109 clntbudp_bufcreate(raddr, program, version, wait, sockp, sendsz, recvsz)
110 	struct sockaddr_in *raddr;
111 	rpcprog_t program;
112 	rpcvers_t version;
113 	struct timeval wait;
114 	int *sockp;
115 	uint_t sendsz;
116 	uint_t recvsz;
117 {
118 	CLIENT *cl;
119 	struct cu_data *cu;
120 	struct rpc_msg call_msg;
121 
122 	cl = (CLIENT *)bkmem_alloc(sizeof (CLIENT));
123 	if (cl == NULL) {
124 		errno = ENOMEM;
125 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
126 		rpc_createerr.cf_error.re_errno = errno;
127 		return ((CLIENT *)NULL);
128 	}
129 	sendsz = ((sendsz + 3) / 4) * 4;
130 	recvsz = ((recvsz + 3) / 4) * 4;
131 	cu = (struct cu_data *)bkmem_alloc(sizeof (*cu) + sendsz + recvsz);
132 	if (cu == NULL) {
133 		errno = ENOMEM;
134 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
135 		rpc_createerr.cf_error.re_errno = errno;
136 		goto fooy;
137 	}
138 	cu->cu_outbuf = &cu->cu_inbuf[recvsz];
139 
140 	if (raddr->sin_port == 0) {
141 		ushort_t port;
142 		if ((port = bpmap_getport(program, version,
143 				&(rpc_createerr.cf_stat), raddr, NULL)) == 0) {
144 			goto fooy;
145 		}
146 		raddr->sin_port = htons(port);
147 	}
148 	cl->cl_ops = clntbudp_ops();
149 	cl->cl_private = (caddr_t)cu;
150 	cu->cu_raddr = *raddr;
151 	cu->cu_rlen = sizeof (cu->cu_raddr);
152 	cu->cu_wait = wait;
153 	cu->cu_total.tv_sec = -1;
154 	cu->cu_total.tv_usec = -1;
155 	cu->cu_sendsz = sendsz;
156 	cu->cu_recvsz = recvsz;
157 	call_msg.rm_xid = (uint_t)prom_gettime() + 1;
158 	call_msg.rm_direction = CALL;
159 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
160 	call_msg.rm_call.cb_prog = program;
161 	call_msg.rm_call.cb_vers = version;
162 	xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
163 	    sendsz, XDR_ENCODE);
164 	if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
165 		goto fooy;
166 	}
167 	cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
168 	cu->cu_closeit = FALSE;
169 
170 	if (*sockp < 0) {
171 		struct sockaddr_in from;
172 
173 		*sockp = socket(PF_INET, SOCK_DGRAM, 0);
174 		if (*sockp < 0) {
175 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
176 			rpc_createerr.cf_error.re_errno = errno;
177 			goto fooy;
178 		}
179 
180 		if (dontroute) {
181 			(void) setsockopt(*sockp, SOL_SOCKET, SO_DONTROUTE,
182 				(const void *)&dontroute, sizeof (dontroute));
183 		}
184 
185 		/* attempt to bind to priv port */
186 		from.sin_family = AF_INET;
187 		ipv4_getipaddr(&from.sin_addr);
188 		from.sin_addr.s_addr = htonl(from.sin_addr.s_addr);
189 		from.sin_port = get_source_port(TRUE);
190 
191 		if (bind(*sockp, (struct sockaddr *)&from, sizeof (from)) < 0) {
192 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
193 			rpc_createerr.cf_error.re_errno = errno;
194 			goto fooy;
195 		}
196 
197 		cu->cu_closeit = TRUE;
198 	}
199 
200 	cu->cu_sock = *sockp;
201 	cl->cl_auth = authnone_create();
202 	return (cl);
203 fooy:
204 	if (cu)
205 		bkmem_free((caddr_t)cu, sizeof (*cu) + sendsz + recvsz);
206 	if (cl)
207 		bkmem_free((caddr_t)cl, sizeof (CLIENT));
208 	return ((CLIENT *)NULL);
209 }
210 
211 CLIENT *
212 clntbudp_create(raddr, program, version, wait, sockp)
213 	struct sockaddr_in *raddr;
214 	rpcprog_t program;
215 	rpcvers_t version;
216 	struct timeval wait;
217 	int *sockp;
218 {
219 
220 	return (clntbudp_bufcreate(raddr, program, version, wait, sockp,
221 	    UDPMSGSIZE, UDPMSGSIZE));
222 }
223 
224 static enum clnt_stat
225 clntbudp_call(cl, proc, xargs, argsp, xresults, resultsp, utimeout)
226 	CLIENT		*cl;		/* client handle */
227 	rpcproc_t	proc;		/* procedure number */
228 	xdrproc_t	xargs;		/* xdr routine for args */
229 	caddr_t		argsp;		/* pointer to args */
230 	xdrproc_t	xresults;	/* xdr routine for results */
231 	caddr_t		resultsp;	/* pointer to results */
232 	struct timeval	utimeout;	/* seconds to wait before giving up */
233 {
234 	struct cu_data *cu;
235 	XDR *xdrs;
236 	int outlen;
237 	int inlen;
238 	socklen_t fromlen;
239 	struct sockaddr_in from;
240 	struct rpc_msg reply_msg;
241 	XDR reply_xdrs;
242 	uint_t xdelay;
243 	int wait_time;
244 	bool_t ok;
245 	int nrefreshes = 2;	/* number of times to refresh cred */
246 	struct timeval timeout;
247 	int errors;
248 	short send_retries = RPC_UDP_SEND_RETRIES;
249 
250 	cu = (struct cu_data *)cl->cl_private;
251 	if (cu->cu_total.tv_usec == -1)
252 		timeout = utimeout;	/* use supplied timeout */
253 	else
254 		timeout = cu->cu_total; /* use default timeout */
255 
256 	/*
257 	 * set a media level timeout
258 	 */
259 	xdelay = cu->cu_wait.tv_sec + 1000 + cu->cu_wait.tv_usec / 1000;
260 	(void) setsockopt(cu->cu_sock, SOL_SOCKET, SO_RCVTIMEO,
261 				(void *)&xdelay, sizeof (xdelay));
262 
263 	wait_time = (timeout.tv_sec * 1000) + (timeout.tv_usec / 1000);
264 	if (wait_time == 0)
265 		wait_time = RPC_RCVWAIT_MSEC;
266 	wait_time += prom_gettime();
267 
268 	errors = 0;
269 
270 call_again:
271 	xdrs = &(cu->cu_outxdrs);
272 	xdrs->x_op = XDR_ENCODE;
273 	(void) XDR_SETPOS(xdrs, cu->cu_xdrpos);
274 	/*
275 	 * the transaction is the first thing in the out buffer
276 	 */
277 	(*(ushort_t *)(cu->cu_outbuf))++;
278 	if ((! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
279 	    (! AUTH_MARSHALL(cl->cl_auth, xdrs, NULL)) ||
280 	    (! (*xargs)(xdrs, argsp)))
281 		return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
282 	outlen = (int)XDR_GETPOS(xdrs);
283 
284 send_again:
285 	if (sendto(cu->cu_sock, cu->cu_outbuf, outlen, 0,
286 	    (struct sockaddr *)&(cu->cu_raddr), cu->cu_rlen)
287 	    != outlen) {
288 		if (errno == ETIMEDOUT) {
289 			/*
290 			 * sendto() times out probably because
291 			 * ARP times out while waiting for reply.
292 			 * We retry sending RPC message again.
293 			 */
294 			if (send_retries-- > 0) {
295 				dprintf("clntbudp_call: timedout, try sending"
296 				    "RPC again\n");
297 				errno = 0;
298 				goto send_again;
299 			}
300 			cu->cu_error.re_status = RPC_TIMEDOUT;
301 		} else {
302 			cu->cu_error.re_status = RPC_CANTSEND;
303 		}
304 		cu->cu_error.re_errno = errno;
305 		return (cu->cu_error.re_status);
306 	}
307 
308 	/*
309 	 * sub-optimal code appears here because we have
310 	 * some clock time to spare while the packets are in flight.
311 	 * (We assume that this is actually only executed once.)
312 	 */
313 recv_again:
314 	reply_msg.acpted_rply.ar_verf = _null_auth;
315 	reply_msg.acpted_rply.ar_results.where = resultsp;
316 	reply_msg.acpted_rply.ar_results.proc = xresults;
317 
318 	for (;;) {
319 		if (errors >= RPC_ALLOWABLE_ERRORS)
320 			return (cu->cu_error.re_status);
321 
322 		if (prom_gettime() >= wait_time) {
323 			cu->cu_error.re_errno = ETIMEDOUT;
324 			return (cu->cu_error.re_status = RPC_TIMEDOUT);
325 		}
326 
327 		/*
328 		 * Use MSG_DONTWAIT because we have set
329 		 * a media level timeout above.
330 		 */
331 		fromlen = sizeof (struct sockaddr);
332 
333 		inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
334 				(int)cu->cu_recvsz, MSG_DONTWAIT,
335 				(struct sockaddr *)&from, &fromlen);
336 
337 		if (inlen < 0) {
338 			if (errno == EWOULDBLOCK) {
339 				/*
340 				 * Media level has timedout
341 				 * and no more data in buffers.
342 				 */
343 				goto send_again;
344 			}
345 
346 			cu->cu_error.re_status = RPC_CANTRECV;
347 			if (errno == ETIMEDOUT) {
348 				errno = ETIMEDOUT;
349 				cu->cu_error.re_status = RPC_TIMEDOUT;
350 			}
351 
352 			cu->cu_error.re_errno = errno;
353 			return (cu->cu_error.re_status);
354 		}
355 
356 		if (inlen < sizeof (uint32_t))
357 			continue;
358 
359 		/* see if reply transaction id matches sent id */
360 		if (*((uint32_t *)(cu->cu_inbuf)) !=
361 				*((uint32_t *)(cu->cu_outbuf))) {
362 			dprintf("clntbudp_call: xid: 0x%x != 0x%x\n",
363 				*(uint32_t *)(cu->cu_inbuf),
364 				*(uint32_t *)(cu->cu_outbuf));
365 			continue;
366 		}
367 		/* we now assume we have the proper reply */
368 		break;
369 	}
370 
371 	/*
372 	 * now decode and validate the response
373 	 */
374 	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (uint_t)inlen, XDR_DECODE);
375 	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
376 	/* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
377 	if (!ok) {
378 		cu->cu_error.re_status = RPC_CANTDECODERES;
379 		return (cu->cu_error.re_status);
380 	}
381 
382 	_seterr_reply(&reply_msg, &(cu->cu_error));
383 	if (cu->cu_error.re_status == RPC_SUCCESS) {
384 		if (! AUTH_VALIDATE(cl->cl_auth,
385 			&reply_msg.acpted_rply.ar_verf)) {
386 			cu->cu_error.re_status = RPC_AUTHERROR;
387 			cu->cu_error.re_why = AUTH_INVALIDRESP;
388 			errors++;
389 			goto call_again;
390 		}
391 		if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
392 			xdrs->x_op = XDR_FREE;
393 			(void) xdr_opaque_auth(xdrs,
394 			    &(reply_msg.acpted_rply.ar_verf));
395 		}
396 		return (cu->cu_error.re_status);
397 	}  /* end successful completion */
398 
399 	if (cu->cu_error.re_status == RPC_AUTHERROR) {
400 		/* maybe our credentials need to be refreshed ... */
401 		if (nrefreshes > 0 &&
402 			AUTH_REFRESH(cl->cl_auth, NULL, NULL)) {
403 			nrefreshes--;
404 		}
405 		errors++;
406 		goto call_again;
407 	}
408 
409 	/* Just keep trying till there's no data... */
410 	errors++;
411 	dprintf("clntbudp_call: from: %s, error: ",
412 		inet_ntoa(from.sin_addr));
413 	rpc_disperr(&cu->cu_error);
414 	goto recv_again;
415 }
416 
417 static void
418 clntbudp_geterr(cl, errp)
419 	CLIENT *cl;
420 	struct rpc_err *errp;
421 {
422 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
423 
424 	*errp = cu->cu_error;
425 }
426 
427 
428 static bool_t
429 clntbudp_freeres(cl, xdr_res, res_ptr)
430 	CLIENT *cl;
431 	xdrproc_t xdr_res;
432 	caddr_t res_ptr;
433 {
434 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
435 	XDR *xdrs = &(cu->cu_outxdrs);
436 
437 	xdrs->x_op = XDR_FREE;
438 	return ((*xdr_res)(xdrs, res_ptr));
439 }
440 
441 static void
442 clntbudp_abort()
443 	/* CLIENT *h; */
444 {
445 }
446 
447 /* ARGSUSED */
448 static bool_t
449 clntbudp_control(cl, request, info)
450 	CLIENT *cl;
451 	int request;
452 	char *info;
453 {
454 	/* CLNT_CONTROL is not used in boot */
455 	return (FALSE);
456 }
457 
458 static void
459 clntbudp_destroy(cl)
460 	CLIENT *cl;
461 {
462 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
463 
464 	if (cu->cu_closeit) {
465 		(void) socket_close(cu->cu_sock);
466 	}
467 	XDR_DESTROY(&(cu->cu_outxdrs));
468 	bkmem_free((caddr_t)cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
469 	bkmem_free((caddr_t)cl, sizeof (CLIENT));
470 }
471 
472 static struct clnt_ops *
473 clntbudp_ops()
474 {
475 	static struct clnt_ops ops;
476 
477 	if (ops.cl_call == NULL) {
478 		ops.cl_call = clntbudp_call;
479 		ops.cl_abort = clntbudp_abort;
480 		ops.cl_geterr = clntbudp_geterr;
481 		ops.cl_freeres = clntbudp_freeres;
482 		ops.cl_destroy = clntbudp_destroy;
483 		ops.cl_control = clntbudp_control;
484 	}
485 	return (&ops);
486 }
487