xref: /illumos-gate/usr/src/stand/lib/fs/nfs/clnt_budp.c (revision a2cd9e1884647e1e412c282879881873b71c84df)
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 extern 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 *
clntbudp_bufcreate(struct sockaddr_in * raddr,rpcprog_t program,rpcvers_t version,struct timeval wait,int * sockp,uint_t sendsz,uint_t recvsz)109 clntbudp_bufcreate(struct sockaddr_in *raddr, rpcprog_t program,
110     rpcvers_t version, struct timeval wait, int *sockp, uint_t sendsz,
111     uint_t recvsz)
112 {
113 	CLIENT *cl;
114 	struct cu_data *cu;
115 	struct rpc_msg call_msg;
116 
117 	cl = (CLIENT *)bkmem_alloc(sizeof (CLIENT));
118 	if (cl == NULL) {
119 		errno = ENOMEM;
120 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
121 		rpc_createerr.cf_error.re_errno = errno;
122 		return ((CLIENT *)NULL);
123 	}
124 	sendsz = ((sendsz + 3) / 4) * 4;
125 	recvsz = ((recvsz + 3) / 4) * 4;
126 	cu = (struct cu_data *)bkmem_alloc(sizeof (*cu) + sendsz + recvsz);
127 	if (cu == NULL) {
128 		errno = ENOMEM;
129 		rpc_createerr.cf_stat = RPC_SYSTEMERROR;
130 		rpc_createerr.cf_error.re_errno = errno;
131 		goto fooy;
132 	}
133 	cu->cu_outbuf = &cu->cu_inbuf[recvsz];
134 
135 	if (raddr->sin_port == 0) {
136 		ushort_t port;
137 		if ((port = bpmap_getport(program, version,
138 		    &(rpc_createerr.cf_stat), raddr, NULL)) == 0) {
139 			goto fooy;
140 		}
141 		raddr->sin_port = htons(port);
142 	}
143 	cl->cl_ops = clntbudp_ops();
144 	cl->cl_private = (caddr_t)cu;
145 	cu->cu_raddr = *raddr;
146 	cu->cu_rlen = sizeof (cu->cu_raddr);
147 	cu->cu_wait = wait;
148 	cu->cu_total.tv_sec = -1;
149 	cu->cu_total.tv_usec = -1;
150 	cu->cu_sendsz = sendsz;
151 	cu->cu_recvsz = recvsz;
152 	call_msg.rm_xid = (uint_t)prom_gettime() + 1;
153 	call_msg.rm_direction = CALL;
154 	call_msg.rm_call.cb_rpcvers = RPC_MSG_VERSION;
155 	call_msg.rm_call.cb_prog = program;
156 	call_msg.rm_call.cb_vers = version;
157 	xdrmem_create(&(cu->cu_outxdrs), cu->cu_outbuf,
158 	    sendsz, XDR_ENCODE);
159 	if (! xdr_callhdr(&(cu->cu_outxdrs), &call_msg)) {
160 		goto fooy;
161 	}
162 	cu->cu_xdrpos = XDR_GETPOS(&(cu->cu_outxdrs));
163 	cu->cu_closeit = FALSE;
164 
165 	if (*sockp < 0) {
166 		struct sockaddr_in from;
167 
168 		*sockp = socket(PF_INET, SOCK_DGRAM, 0);
169 		if (*sockp < 0) {
170 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
171 			rpc_createerr.cf_error.re_errno = errno;
172 			goto fooy;
173 		}
174 
175 		if (dontroute) {
176 			(void) setsockopt(*sockp, SOL_SOCKET, SO_DONTROUTE,
177 			    (const void *)&dontroute, sizeof (dontroute));
178 		}
179 
180 		/* attempt to bind to priv port */
181 		from.sin_family = AF_INET;
182 		ipv4_getipaddr(&from.sin_addr);
183 		from.sin_addr.s_addr = htonl(from.sin_addr.s_addr);
184 		from.sin_port = get_source_port(TRUE);
185 
186 		if (bind(*sockp, (struct sockaddr *)&from, sizeof (from)) < 0) {
187 			rpc_createerr.cf_stat = RPC_SYSTEMERROR;
188 			rpc_createerr.cf_error.re_errno = errno;
189 			goto fooy;
190 		}
191 
192 		cu->cu_closeit = TRUE;
193 	}
194 
195 	cu->cu_sock = *sockp;
196 	cl->cl_auth = authnone_create();
197 	return (cl);
198 fooy:
199 	if (cu)
200 		bkmem_free((caddr_t)cu, sizeof (*cu) + sendsz + recvsz);
201 	if (cl)
202 		bkmem_free((caddr_t)cl, sizeof (CLIENT));
203 	return ((CLIENT *)NULL);
204 }
205 
206 CLIENT *
clntbudp_create(struct sockaddr_in * raddr,rpcprog_t program,rpcvers_t version,struct timeval wait,int * sockp)207 clntbudp_create(struct sockaddr_in *raddr, rpcprog_t program,
208     rpcvers_t version, struct timeval wait, int *sockp)
209 {
210 
211 	return (clntbudp_bufcreate(raddr, program, version, wait, sockp,
212 	    UDPMSGSIZE, UDPMSGSIZE));
213 }
214 
215 static enum clnt_stat
clntbudp_call(CLIENT * cl,rpcproc_t proc,xdrproc_t xargs,caddr_t argsp,xdrproc_t xresults,caddr_t resultsp,struct timeval utimeout)216 clntbudp_call(CLIENT *cl, rpcproc_t proc, xdrproc_t xargs, caddr_t argsp,
217     xdrproc_t  xresults, caddr_t resultsp, struct timeval utimeout)
218 {
219 	struct cu_data *cu;
220 	XDR *xdrs;
221 	int outlen;
222 	int inlen;
223 	socklen_t fromlen;
224 	struct sockaddr_in from;
225 	struct rpc_msg reply_msg;
226 	XDR reply_xdrs;
227 	uint_t xdelay;
228 	int wait_time;
229 	bool_t ok;
230 	int nrefreshes = 2;	/* number of times to refresh cred */
231 	struct timeval timeout;
232 	int errors;
233 	short send_retries = RPC_UDP_SEND_RETRIES;
234 
235 	cu = (struct cu_data *)cl->cl_private;
236 	if (cu->cu_total.tv_usec == -1)
237 		timeout = utimeout;	/* use supplied timeout */
238 	else
239 		timeout = cu->cu_total; /* use default timeout */
240 
241 	/*
242 	 * set a media level timeout
243 	 */
244 	xdelay = cu->cu_wait.tv_sec + 1000 + cu->cu_wait.tv_usec / 1000;
245 	(void) setsockopt(cu->cu_sock, SOL_SOCKET, SO_RCVTIMEO,
246 	    (void *)&xdelay, sizeof (xdelay));
247 
248 	wait_time = (timeout.tv_sec * 1000) + (timeout.tv_usec / 1000);
249 	if (wait_time == 0)
250 		wait_time = RPC_RCVWAIT_MSEC;
251 	wait_time += prom_gettime();
252 
253 	errors = 0;
254 
255 call_again:
256 	xdrs = &(cu->cu_outxdrs);
257 	xdrs->x_op = XDR_ENCODE;
258 	(void) XDR_SETPOS(xdrs, cu->cu_xdrpos);
259 	/*
260 	 * the transaction is the first thing in the out buffer
261 	 */
262 	(*(ushort_t *)(cu->cu_outbuf))++;
263 	if ((! XDR_PUTINT32(xdrs, (int32_t *)&proc)) ||
264 	    (! AUTH_MARSHALL(cl->cl_auth, xdrs, NULL)) ||
265 	    (! (*xargs)(xdrs, argsp)))
266 		return (cu->cu_error.re_status = RPC_CANTENCODEARGS);
267 	outlen = (int)XDR_GETPOS(xdrs);
268 
269 send_again:
270 	if (sendto(cu->cu_sock, cu->cu_outbuf, outlen, 0,
271 	    (struct sockaddr *)&(cu->cu_raddr), cu->cu_rlen)
272 	    != outlen) {
273 		if (errno == ETIMEDOUT) {
274 			/*
275 			 * sendto() times out probably because
276 			 * ARP times out while waiting for reply.
277 			 * We retry sending RPC message again.
278 			 */
279 			if (send_retries-- > 0) {
280 				dprintf("clntbudp_call: timedout, try sending"
281 				    "RPC again\n");
282 				errno = 0;
283 				goto send_again;
284 			}
285 			cu->cu_error.re_status = RPC_TIMEDOUT;
286 		} else {
287 			cu->cu_error.re_status = RPC_CANTSEND;
288 		}
289 		cu->cu_error.re_errno = errno;
290 		return (cu->cu_error.re_status);
291 	}
292 
293 	/*
294 	 * sub-optimal code appears here because we have
295 	 * some clock time to spare while the packets are in flight.
296 	 * (We assume that this is actually only executed once.)
297 	 */
298 recv_again:
299 	reply_msg.acpted_rply.ar_verf = _null_auth;
300 	reply_msg.acpted_rply.ar_results.where = resultsp;
301 	reply_msg.acpted_rply.ar_results.proc = xresults;
302 
303 	for (;;) {
304 		if (errors >= RPC_ALLOWABLE_ERRORS)
305 			return (cu->cu_error.re_status);
306 
307 		if (prom_gettime() >= wait_time) {
308 			cu->cu_error.re_errno = ETIMEDOUT;
309 			return (cu->cu_error.re_status = RPC_TIMEDOUT);
310 		}
311 
312 		/*
313 		 * Use MSG_DONTWAIT because we have set
314 		 * a media level timeout above.
315 		 */
316 		fromlen = sizeof (struct sockaddr);
317 
318 		inlen = recvfrom(cu->cu_sock, cu->cu_inbuf,
319 		    (int)cu->cu_recvsz, MSG_DONTWAIT,
320 		    (struct sockaddr *)&from, &fromlen);
321 
322 		if (inlen < 0) {
323 			if (errno == EWOULDBLOCK) {
324 				/*
325 				 * Media level has timedout
326 				 * and no more data in buffers.
327 				 */
328 				goto send_again;
329 			}
330 
331 			cu->cu_error.re_status = RPC_CANTRECV;
332 			if (errno == ETIMEDOUT) {
333 				errno = ETIMEDOUT;
334 				cu->cu_error.re_status = RPC_TIMEDOUT;
335 			}
336 
337 			cu->cu_error.re_errno = errno;
338 			return (cu->cu_error.re_status);
339 		}
340 
341 		if (inlen < sizeof (uint32_t))
342 			continue;
343 
344 		/* see if reply transaction id matches sent id */
345 		if (*((uint32_t *)(cu->cu_inbuf)) !=
346 		    *((uint32_t *)(cu->cu_outbuf))) {
347 			dprintf("clntbudp_call: xid: 0x%x != 0x%x\n",
348 			    *(uint32_t *)(cu->cu_inbuf),
349 			    *(uint32_t *)(cu->cu_outbuf));
350 			continue;
351 		}
352 		/* we now assume we have the proper reply */
353 		break;
354 	}
355 
356 	/*
357 	 * now decode and validate the response
358 	 */
359 	xdrmem_create(&reply_xdrs, cu->cu_inbuf, (uint_t)inlen, XDR_DECODE);
360 	ok = xdr_replymsg(&reply_xdrs, &reply_msg);
361 	/* XDR_DESTROY(&reply_xdrs);  save a few cycles on noop destroy */
362 	if (!ok) {
363 		cu->cu_error.re_status = RPC_CANTDECODERES;
364 		return (cu->cu_error.re_status);
365 	}
366 
367 	_seterr_reply(&reply_msg, &(cu->cu_error));
368 	if (cu->cu_error.re_status == RPC_SUCCESS) {
369 		if (! AUTH_VALIDATE(cl->cl_auth,
370 		    &reply_msg.acpted_rply.ar_verf)) {
371 			cu->cu_error.re_status = RPC_AUTHERROR;
372 			cu->cu_error.re_why = AUTH_INVALIDRESP;
373 			errors++;
374 			goto call_again;
375 		}
376 		if (reply_msg.acpted_rply.ar_verf.oa_base != NULL) {
377 			xdrs->x_op = XDR_FREE;
378 			(void) xdr_opaque_auth(xdrs,
379 			    &(reply_msg.acpted_rply.ar_verf));
380 		}
381 		return (cu->cu_error.re_status);
382 	}  /* end successful completion */
383 
384 	if (cu->cu_error.re_status == RPC_AUTHERROR) {
385 		/* maybe our credentials need to be refreshed ... */
386 		if (nrefreshes > 0 &&
387 		    AUTH_REFRESH(cl->cl_auth, NULL, NULL)) {
388 			nrefreshes--;
389 		}
390 		errors++;
391 		goto call_again;
392 	}
393 
394 	/* Just keep trying till there's no data... */
395 	errors++;
396 	dprintf("clntbudp_call: from: %s, error: ",
397 	    inet_ntoa(from.sin_addr));
398 	rpc_disperr(&cu->cu_error);
399 	goto recv_again;
400 }
401 
402 static void
clntbudp_geterr(CLIENT * cl,struct rpc_err * errp)403 clntbudp_geterr(CLIENT *cl, struct rpc_err *errp)
404 {
405 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
406 
407 	*errp = cu->cu_error;
408 }
409 
410 
411 static bool_t
clntbudp_freeres(CLIENT * cl,xdrproc_t xdr_res,caddr_t res_ptr)412 clntbudp_freeres(CLIENT *cl, xdrproc_t xdr_res, caddr_t res_ptr)
413 {
414 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
415 	XDR *xdrs = &(cu->cu_outxdrs);
416 
417 	xdrs->x_op = XDR_FREE;
418 	return ((*xdr_res)(xdrs, res_ptr));
419 }
420 
421 static void
clntbudp_abort(void)422 clntbudp_abort(void)
423 {
424 }
425 
426 /* ARGSUSED */
427 static bool_t
clntbudp_control(CLIENT * cl,int request,char * info)428 clntbudp_control(CLIENT *cl, int request, char *info)
429 {
430 	/* CLNT_CONTROL is not used in boot */
431 	return (FALSE);
432 }
433 
434 static void
clntbudp_destroy(CLIENT * cl)435 clntbudp_destroy(CLIENT *cl)
436 {
437 	struct cu_data *cu = (struct cu_data *)cl->cl_private;
438 
439 	if (cu->cu_closeit) {
440 		(void) socket_close(cu->cu_sock);
441 	}
442 	XDR_DESTROY(&(cu->cu_outxdrs));
443 	bkmem_free((caddr_t)cu, (sizeof (*cu) + cu->cu_sendsz + cu->cu_recvsz));
444 	bkmem_free((caddr_t)cl, sizeof (CLIENT));
445 }
446 
447 static struct clnt_ops *
clntbudp_ops(void)448 clntbudp_ops(void)
449 {
450 	static struct clnt_ops ops;
451 
452 	if (ops.cl_call == NULL) {
453 		ops.cl_call = clntbudp_call;
454 		ops.cl_abort = clntbudp_abort;
455 		ops.cl_geterr = clntbudp_geterr;
456 		ops.cl_freeres = clntbudp_freeres;
457 		ops.cl_destroy = clntbudp_destroy;
458 		ops.cl_control = clntbudp_control;
459 	}
460 	return (&ops);
461 }
462