summaryrefslogtreecommitdiffstats
path: root/net/sunrpc/rpcb_clnt.c
blob: 24db2b4d12d3e43b3faf944262a10105ecaca898 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
/*
 * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
 * protocol
 *
 * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
 * RFC 3530: "Network File System (NFS) version 4 Protocol"
 *
 * Original: Gilles Quillard, Bull Open Source, 2005 <gilles.quillard@bull.net>
 * Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
 *
 * Descended from net/sunrpc/pmap_clnt.c,
 *  Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
 */

#include <linux/module.h>

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/kernel.h>
#include <linux/errno.h>

#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xprtsock.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_BIND
#endif

#define RPCBIND_PROGRAM		(100000u)
#define RPCBIND_PORT		(111u)

#define RPCBVERS_2		(2u)
#define RPCBVERS_3		(3u)
#define RPCBVERS_4		(4u)

enum {
	RPCBPROC_NULL,
	RPCBPROC_SET,
	RPCBPROC_UNSET,
	RPCBPROC_GETPORT,
	RPCBPROC_GETADDR = 3,		/* alias for GETPORT */
	RPCBPROC_DUMP,
	RPCBPROC_CALLIT,
	RPCBPROC_BCAST = 5,		/* alias for CALLIT */
	RPCBPROC_GETTIME,
	RPCBPROC_UADDR2TADDR,
	RPCBPROC_TADDR2UADDR,
	RPCBPROC_GETVERSADDR,
	RPCBPROC_INDIRECT,
	RPCBPROC_GETADDRLIST,
	RPCBPROC_GETSTAT,
};

#define RPCB_HIGHPROC_2		RPCBPROC_CALLIT
#define RPCB_HIGHPROC_3		RPCBPROC_TADDR2UADDR
#define RPCB_HIGHPROC_4		RPCBPROC_GETSTAT

/*
 * r_owner
 *
 * The "owner" is allowed to unset a service in the rpcbind database.
 * We always use the following (arbitrary) fixed string.
 */
#define RPCB_OWNER_STRING	"rpcb"
#define RPCB_MAXOWNERLEN	sizeof(RPCB_OWNER_STRING)

static void			rpcb_getport_done(struct rpc_task *, void *);
static void			rpcb_map_release(void *data);
static struct rpc_program	rpcb_program;

struct rpcbind_args {
	struct rpc_xprt *	r_xprt;

	u32			r_prog;
	u32			r_vers;
	u32			r_prot;
	unsigned short		r_port;
	const char *		r_netid;
	const char *		r_addr;
	const char *		r_owner;

	int			r_status;
};

static struct rpc_procinfo rpcb_procedures2[];
static struct rpc_procinfo rpcb_procedures3[];
static struct rpc_procinfo rpcb_procedures4[];

struct rpcb_info {
	u32			rpc_vers;
	struct rpc_procinfo *	rpc_proc;
};

static struct rpcb_info rpcb_next_version[];
static struct rpcb_info rpcb_next_version6[];

static const struct rpc_call_ops rpcb_getport_ops = {
	.rpc_call_done		= rpcb_getport_done,
	.rpc_release		= rpcb_map_release,
};

static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
{
	xprt_clear_binding(xprt);
	rpc_wake_up_status(&xprt->binding, status);
}

static void rpcb_map_release(void *data)
{
	struct rpcbind_args *map = data;

	rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
	xprt_put(map->r_xprt);
	kfree(map);
}

static const struct sockaddr_in rpcb_inaddr_loopback = {
	.sin_family		= AF_INET,
	.sin_addr.s_addr	= htonl(INADDR_LOOPBACK),
	.sin_port		= htons(RPCBIND_PORT),
};

static const struct sockaddr_in6 rpcb_in6addr_loopback = {
	.sin6_family		= AF_INET6,
	.sin6_addr		= IN6ADDR_LOOPBACK_INIT,
	.sin6_port		= htons(RPCBIND_PORT),
};

static struct rpc_clnt *rpcb_create_local(struct sockaddr *addr,
					  size_t addrlen, u32 version)
{
	struct rpc_create_args args = {
		.protocol	= XPRT_TRANSPORT_UDP,
		.address	= addr,
		.addrsize	= addrlen,
		.servername	= "localhost",
		.program	= &rpcb_program,
		.version	= version,
		.authflavor	= RPC_AUTH_UNIX,
		.flags		= RPC_CLNT_CREATE_NOPING,
	};

	return rpc_create(&args);
}

static struct rpc_clnt *rpcb_create(char *hostname, struct sockaddr *srvaddr,
				    size_t salen, int proto, u32 version)
{
	struct rpc_create_args args = {
		.protocol	= proto,
		.address	= srvaddr,
		.addrsize	= salen,
		.servername	= hostname,
		.program	= &rpcb_program,
		.version	= version,
		.authflavor	= RPC_AUTH_UNIX,
		.flags		= (RPC_CLNT_CREATE_NOPING |
					RPC_CLNT_CREATE_NONPRIVPORT),
	};

	switch (srvaddr->sa_family) {
	case AF_INET:
		((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
		break;
	case AF_INET6:
		((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
		break;
	default:
		return NULL;
	}

	return rpc_create(&args);
}

static int rpcb_register_call(struct sockaddr *addr, size_t addrlen,
			      u32 version, struct rpc_message *msg,
			      int *result)
{
	struct rpc_clnt *rpcb_clnt;
	int error = 0;

	*result = 0;

	rpcb_clnt = rpcb_create_local(addr, addrlen, version);
	if (!IS_ERR(rpcb_clnt)) {
		error = rpc_call_sync(rpcb_clnt, msg, 0);
		rpc_shutdown_client(rpcb_clnt);
	} else
		error = PTR_ERR(rpcb_clnt);

	if (error < 0)
		printk(KERN_WARNING "RPC: failed to contact local rpcbind "
				"server (errno %d).\n", -error);
	dprintk("RPC:       registration status %d/%d\n", error, *result);

	return error;
}

/**
 * rpcb_register - set or unset a port registration with the local rpcbind svc
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to register
 * @port: port value to register
 * @okay: OUT: result code
 *
 * RPC services invoke this function to advertise their contact
 * information via the system's rpcbind daemon.  RPC services
 * invoke this function once for each [program, version, transport]
 * tuple they wish to advertise.
 *
 * Callers may also unregister RPC services that are no longer
 * available by setting the passed-in port to zero.  This removes
 * all registered transports for [program, version] from the local
 * rpcbind database.
 *
 * Returns zero if the registration request was dispatched
 * successfully and a reply was received.  The rpcbind daemon's
 * boolean result code is stored in *okay.
 *
 * Returns an errno value and sets *result to zero if there was
 * some problem that prevented the rpcbind request from being
 * dispatched, or if the rpcbind daemon did not respond within
 * the timeout.
 *
 * This function uses rpcbind protocol version 2 to contact the
 * local rpcbind daemon.
 *
 * Registration works over both AF_INET and AF_INET6, and services
 * registered via this function are advertised as available for any
 * address.  If the local rpcbind daemon is listening on AF_INET6,
 * services registered via this function will be advertised on
 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
 * addresses).
 */
int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
{
	struct rpcbind_args map = {
		.r_prog		= prog,
		.r_vers		= vers,
		.r_prot		= prot,
		.r_port		= port,
	};
	struct rpc_message msg = {
		.rpc_argp	= &map,
		.rpc_resp	= okay,
	};

	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
			"rpcbind\n", (port ? "" : "un"),
			prog, vers, prot, port);

	msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
	if (port)
		msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];

	return rpcb_register_call((struct sockaddr *)&rpcb_inaddr_loopback,
					sizeof(rpcb_inaddr_loopback),
					RPCBVERS_2, &msg, okay);
}

/*
 * Fill in AF_INET family-specific arguments to register
 */
static int rpcb_register_netid4(struct sockaddr_in *address_to_register,
				struct rpc_message *msg)
{
	struct rpcbind_args *map = msg->rpc_argp;
	unsigned short port = ntohs(address_to_register->sin_port);
	char buf[32];

	/* Construct AF_INET universal address */
	snprintf(buf, sizeof(buf),
			NIPQUAD_FMT".%u.%u",
			NIPQUAD(address_to_register->sin_addr.s_addr),
			port >> 8, port & 0xff);
	map->r_addr = buf;

	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
		"local rpcbind\n", (port ? "" : "un"),
			map->r_prog, map->r_vers,
			map->r_addr, map->r_netid);

	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
	if (port)
		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];

	return rpcb_register_call((struct sockaddr *)&rpcb_inaddr_loopback,
					sizeof(rpcb_inaddr_loopback),
					RPCBVERS_4, msg, msg->rpc_resp);
}

/*
 * Fill in AF_INET6 family-specific arguments to register
 */
static int rpcb_register_netid6(struct sockaddr_in6 *address_to_register,
				struct rpc_message *msg)
{
	struct rpcbind_args *map = msg->rpc_argp;
	unsigned short port = ntohs(address_to_register->sin6_port);
	char buf[64];

	/* Construct AF_INET6 universal address */
	snprintf(buf, sizeof(buf),
			NIP6_FMT".%u.%u",
			NIP6(address_to_register->sin6_addr),
			port >> 8, port & 0xff);
	map->r_addr = buf;

	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
		"local rpcbind\n", (port ? "" : "un"),
			map->r_prog, map->r_vers,
			map->r_addr, map->r_netid);

	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
	if (port)
		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];

	return rpcb_register_call((struct sockaddr *)&rpcb_in6addr_loopback,
					sizeof(rpcb_in6addr_loopback),
					RPCBVERS_4, msg, msg->rpc_resp);
}

/**
 * rpcb_v4_register - set or unset a port registration with the local rpcbind
 * @program: RPC program number of service to (un)register
 * @version: RPC version number of service to (un)register
 * @address: address family, IP address, and port to (un)register
 * @netid: netid of transport protocol to (un)register
 * @result: result code from rpcbind RPC call
 *
 * RPC services invoke this function to advertise their contact
 * information via the system's rpcbind daemon.  RPC services
 * invoke this function once for each [program, version, address,
 * netid] tuple they wish to advertise.
 *
 * Callers may also unregister RPC services that are no longer
 * available by setting the port number in the passed-in address
 * to zero.  Callers pass a netid of "" to unregister all
 * transport netids associated with [program, version, address].
 *
 * Returns zero if the registration request was dispatched
 * successfully and a reply was received.  The rpcbind daemon's
 * result code is stored in *result.
 *
 * Returns an errno value and sets *result to zero if there was
 * some problem that prevented the rpcbind request from being
 * dispatched, or if the rpcbind daemon did not respond within
 * the timeout.
 *
 * This function uses rpcbind protocol version 4 to contact the
 * local rpcbind daemon.  The local rpcbind daemon must support
 * version 4 of the rpcbind protocol in order for these functions
 * to register a service successfully.
 *
 * Supported netids include "udp" and "tcp" for UDP and TCP over
 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
 * respectively.
 *
 * The contents of @address determine the address family and the
 * port to be registered.  The usual practice is to pass INADDR_ANY
 * as the raw address, but specifying a non-zero address is also
 * supported by this API if the caller wishes to advertise an RPC
 * service on a specific network interface.
 *
 * Note that passing in INADDR_ANY does not create the same service
 * registration as IN6ADDR_ANY.  The former advertises an RPC
 * service on any IPv4 address, but not on IPv6.  The latter
 * advertises the service on all IPv4 and IPv6 addresses.
 */
int rpcb_v4_register(const u32 program, const u32 version,
		     const struct sockaddr *address, const char *netid,
		     int *result)
{
	struct rpcbind_args map = {
		.r_prog		= program,
		.r_vers		= version,
		.r_netid	= netid,
		.r_owner	= RPCB_OWNER_STRING,
	};
	struct rpc_message msg = {
		.rpc_argp	= &map,
		.rpc_resp	= result,
	};

	*result = 0;

	switch (address->sa_family) {
	case AF_INET:
		return rpcb_register_netid4((struct sockaddr_in *)address,
					    &msg);
	case AF_INET6:
		return rpcb_register_netid6((struct sockaddr_in6 *)address,
					    &msg);
	}

	return -EAFNOSUPPORT;
}

/**
 * rpcb_getport_sync - obtain the port for an RPC service on a given host
 * @sin: address of remote peer
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to use to make this request
 *
 * Return value is the requested advertised port number,
 * or a negative errno value.
 *
 * Called from outside the RPC client in a synchronous task context.
 * Uses default timeout parameters specified by underlying transport.
 *
 * XXX: Needs to support IPv6
 */
int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
{
	struct rpcbind_args map = {
		.r_prog		= prog,
		.r_vers		= vers,
		.r_prot		= prot,
		.r_port		= 0,
	};
	struct rpc_message msg = {
		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
		.rpc_argp	= &map,
		.rpc_resp	= &map.r_port,
	};
	struct rpc_clnt	*rpcb_clnt;
	int status;

	dprintk("RPC:       %s(" NIPQUAD_FMT ", %u, %u, %d)\n",
		__func__, NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);

	rpcb_clnt = rpcb_create(NULL, (struct sockaddr *)sin,
				sizeof(*sin), prot, RPCBVERS_2);
	if (IS_ERR(rpcb_clnt))
		return PTR_ERR(rpcb_clnt);

	status = rpc_call_sync(rpcb_clnt, &msg, 0);
	rpc_shutdown_client(rpcb_clnt);

	if (status >= 0) {
		if (map.r_port != 0)
			return map.r_port;
		status = -EACCES;
	}
	return status;
}
EXPORT_SYMBOL_GPL(rpcb_getport_sync);

static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
{
	struct rpc_message msg = {
		.rpc_proc = proc,
		.rpc_argp = map,
		.rpc_resp = &map->r_port,
	};
	struct rpc_task_setup task_setup_data = {
		.rpc_client = rpcb_clnt,
		.rpc_message = &msg,
		.callback_ops = &rpcb_getport_ops,
		.callback_data = map,
		.flags = RPC_TASK_ASYNC,
	};

	return rpc_run_task(&task_setup_data);
}

/**
 * rpcb_getport_async - obtain the port for a given RPC service on a given host
 * @task: task that is waiting for portmapper request
 *
 * This one can be called for an ongoing RPC request, and can be used in
 * an async (rpciod) context.
 */
void rpcb_getport_async(struct rpc_task *task)
{
	struct rpc_clnt *clnt = task->tk_client;
	struct rpc_procinfo *proc;
	u32 bind_version;
	struct rpc_xprt *xprt = task->tk_xprt;
	struct rpc_clnt	*rpcb_clnt;
	static struct rpcbind_args *map;
	struct rpc_task	*child;
	struct sockaddr_storage addr;
	struct sockaddr *sap = (struct sockaddr *)&addr;
	size_t salen;
	int status;

	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
		task->tk_pid, __func__,
		clnt->cl_server, clnt->cl_prog, clnt->cl_vers, xprt->prot);

	/* Autobind on cloned rpc clients is discouraged */
	BUG_ON(clnt->cl_parent != clnt);

	/* Put self on the wait queue to ensure we get notified if
	 * some other task is already attempting to bind the port */
	rpc_sleep_on(&xprt->binding, task, NULL);

	if (xprt_test_and_set_binding(xprt)) {
		dprintk("RPC: %5u %s: waiting for another binder\n",
			task->tk_pid, __func__);
		return;
	}

	/* Someone else may have bound if we slept */
	if (xprt_bound(xprt)) {
		status = 0;
		dprintk("RPC: %5u %s: already bound\n",
			task->tk_pid, __func__);
		goto bailout_nofree;
	}

	salen = rpc_peeraddr(clnt, sap, sizeof(addr));

	/* Don't ever use rpcbind v2 for AF_INET6 requests */
	switch (sap->sa_family) {
	case AF_INET:
		proc = rpcb_next_version[xprt->bind_index].rpc_proc;
		bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
		break;
	case AF_INET6:
		proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
		bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
		break;
	default:
		status = -EAFNOSUPPORT;
		dprintk("RPC: %5u %s: bad address family\n",
				task->tk_pid, __func__);
		goto bailout_nofree;
	}
	if (proc == NULL) {
		xprt->bind_index = 0;
		status = -EPFNOSUPPORT;
		dprintk("RPC: %5u %s: no more getport versions available\n",
			task->tk_pid, __func__);
		goto bailout_nofree;
	}

	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
		task->tk_pid, __func__, bind_version);

	rpcb_clnt = rpcb_create(clnt->cl_server, sap, salen, xprt->prot,
				bind_version);
	if (IS_ERR(rpcb_clnt)) {
		status = PTR_ERR(rpcb_clnt);
		dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
			task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
		goto bailout_nofree;
	}

	map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
	if (!map) {
		status = -ENOMEM;
		dprintk("RPC: %5u %s: no memory available\n",
			task->tk_pid, __func__);
		goto bailout_nofree;
	}
	map->r_prog = clnt->cl_prog;
	map->r_vers = clnt->cl_vers;
	map->r_prot = xprt->prot;
	map->r_port = 0;
	map->r_xprt = xprt_get(xprt);
	map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
	map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
	map->r_owner = RPCB_OWNER_STRING;	/* ignored for GETADDR */
	map->r_status = -EIO;

	child = rpcb_call_async(rpcb_clnt, map, proc);
	rpc_release_client(rpcb_clnt);
	if (IS_ERR(child)) {
		/* rpcb_map_release() has freed the arguments */
		dprintk("RPC: %5u %s: rpc_run_task failed\n",
			task->tk_pid, __func__);
		return;
	}
	rpc_put_task(child);

	task->tk_xprt->stat.bind_count++;
	return;

bailout_nofree:
	rpcb_wake_rpcbind_waiters(xprt, status);
	task->tk_status = status;
}
EXPORT_SYMBOL_GPL(rpcb_getport_async);

/*
 * Rpcbind child task calls this callback via tk_exit.
 */
static void rpcb_getport_done(struct rpc_task *child, void *data)
{
	struct rpcbind_args *map = data;
	struct rpc_xprt *xprt = map->r_xprt;
	int status = child->tk_status;

	/* Garbage reply: retry with a lesser rpcbind version */
	if (status == -EIO)
		status = -EPROTONOSUPPORT;

	/* rpcbind server doesn't support this rpcbind protocol version */
	if (status == -EPROTONOSUPPORT)
		xprt->bind_index++;

	if (status < 0) {
		/* rpcbind server not available on remote host? */
		xprt->ops->set_port(xprt, 0);
	} else if (map->r_port == 0) {
		/* Requested RPC service wasn't registered on remote host */
		xprt->ops->set_port(xprt, 0);
		status = -EACCES;
	} else {
		/* Succeeded */
		xprt->ops->set_port(xprt, map->r_port);
		xprt_set_bound(xprt);
		status = 0;
	}

	dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
			child->tk_pid, status, map->r_port);

	map->r_status = status;
}

/*
 * XDR functions for rpcbind
 */

static int rpcb_encode_mapping(struct rpc_rqst *req, __be32 *p,
			       struct rpcbind_args *rpcb)
{
	dprintk("RPC:       rpcb_encode_mapping(%u, %u, %d, %u)\n",
			rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
	*p++ = htonl(rpcb->r_prog);
	*p++ = htonl(rpcb->r_vers);
	*p++ = htonl(rpcb->r_prot);
	*p++ = htonl(rpcb->r_port);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

static int rpcb_decode_getport(struct rpc_rqst *req, __be32 *p,
			       unsigned short *portp)
{
	*portp = (unsigned short) ntohl(*p++);
	dprintk("RPC:       rpcb_decode_getport result %u\n",
			*portp);
	return 0;
}

static int rpcb_decode_set(struct rpc_rqst *req, __be32 *p,
			   unsigned int *boolp)
{
	*boolp = (unsigned int) ntohl(*p++);
	dprintk("RPC:       rpcb_decode_set: call %s\n",
			(*boolp ? "succeeded" : "failed"));
	return 0;
}

static int rpcb_encode_getaddr(struct rpc_rqst *req, __be32 *p,
			       struct rpcbind_args *rpcb)
{
	dprintk("RPC:       rpcb_encode_getaddr(%u, %u, %s)\n",
			rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
	*p++ = htonl(rpcb->r_prog);
	*p++ = htonl(rpcb->r_vers);

	p = xdr_encode_string(p, rpcb->r_netid);
	p = xdr_encode_string(p, rpcb->r_addr);
	p = xdr_encode_string(p, rpcb->r_owner);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	return 0;
}

static int rpcb_decode_getaddr(struct rpc_rqst *req, __be32 *p,
			       unsigned short *portp)
{
	char *addr;
	u32 addr_len;
	int c, i, f, first, val;

	*portp = 0;
	addr_len = ntohl(*p++);

	/*
	 * Simple sanity check.  The smallest possible universal
	 * address is an IPv4 address string containing 11 bytes.
	 */
	if (addr_len < 11 || addr_len > RPCBIND_MAXUADDRLEN)
		goto out_err;

	/*
	 * Start at the end and walk backwards until the first dot
	 * is encountered.  When the second dot is found, we have
	 * both parts of the port number.
	 */
	addr = (char *)p;
	val = 0;
	first = 1;
	f = 1;
	for (i = addr_len - 1; i > 0; i--) {
		c = addr[i];
		if (c >= '0' && c <= '9') {
			val += (c - '0') * f;
			f *= 10;
		} else if (c == '.') {
			if (first) {
				*portp = val;
				val = first = 0;
				f = 1;
			} else {
				*portp |= (val << 8);
				break;
			}
		}
	}

	/*
	 * Simple sanity check.  If we never saw a dot in the reply,
	 * then this was probably just garbage.
	 */
	if (first)
		goto out_err;

	dprintk("RPC:       rpcb_decode_getaddr port=%u\n", *portp);
	return 0;

out_err:
	dprintk("RPC:       rpcbind server returned malformed reply\n");
	return -EIO;
}

#define RPCB_program_sz		(1u)
#define RPCB_version_sz		(1u)
#define RPCB_protocol_sz	(1u)
#define RPCB_port_sz		(1u)
#define RPCB_boolean_sz		(1u)

#define RPCB_netid_sz		(1+XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
#define RPCB_addr_sz		(1+XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
#define RPCB_ownerstring_sz	(1+XDR_QUADLEN(RPCB_MAXOWNERLEN))

#define RPCB_mappingargs_sz	RPCB_program_sz+RPCB_version_sz+	\
				RPCB_protocol_sz+RPCB_port_sz
#define RPCB_getaddrargs_sz	RPCB_program_sz+RPCB_version_sz+	\
				RPCB_netid_sz+RPCB_addr_sz+		\
				RPCB_ownerstring_sz

#define RPCB_setres_sz		RPCB_boolean_sz
#define RPCB_getportres_sz	RPCB_port_sz

/*
 * Note that RFC 1833 does not put any size restrictions on the
 * address string returned by the remote rpcbind database.
 */
#define RPCB_getaddrres_sz	RPCB_addr_sz

#define PROC(proc, argtype, restype)					\
	[RPCBPROC_##proc] = {						\
		.p_proc		= RPCBPROC_##proc,			\
		.p_encode	= (kxdrproc_t) rpcb_encode_##argtype,	\
		.p_decode	= (kxdrproc_t) rpcb_decode_##restype,	\
		.p_arglen	= RPCB_##argtype##args_sz,		\
		.p_replen	= RPCB_##restype##res_sz,		\
		.p_statidx	= RPCBPROC_##proc,			\
		.p_timer	= 0,					\
		.p_name		= #proc,				\
	}

/*
 * Not all rpcbind procedures described in RFC 1833 are implemented
 * since the Linux kernel RPC code requires only these.
 */
static struct rpc_procinfo rpcb_procedures2[] = {
	PROC(SET,		mapping,	set),
	PROC(UNSET,		mapping,	set),
	PROC(GETPORT,		mapping,	getport),
};

static struct rpc_procinfo rpcb_procedures3[] = {
	PROC(SET,		getaddr,	set),
	PROC(UNSET,		getaddr,	set),
	PROC(GETADDR,		getaddr,	getaddr),
};

static struct rpc_procinfo rpcb_procedures4[] = {
	PROC(SET,		getaddr,	set),
	PROC(UNSET,		getaddr,	set),
	PROC(GETADDR,		getaddr,	getaddr),
	PROC(GETVERSADDR,	getaddr,	getaddr),
};

static struct rpcb_info rpcb_next_version[] = {
	{
		.rpc_vers	= RPCBVERS_2,
		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
	},
	{
		.rpc_proc	= NULL,
	},
};

static struct rpcb_info rpcb_next_version6[] = {
	{
		.rpc_vers	= RPCBVERS_4,
		.rpc_proc	= &rpcb_procedures4[RPCBPROC_GETADDR],
	},
	{
		.rpc_vers	= RPCBVERS_3,
		.rpc_proc	= &rpcb_procedures3[RPCBPROC_GETADDR],
	},
	{
		.rpc_proc	= NULL,
	},
};

static struct rpc_version rpcb_version2 = {
	.number		= RPCBVERS_2,
	.nrprocs	= RPCB_HIGHPROC_2,
	.procs		= rpcb_procedures2
};

static struct rpc_version rpcb_version3 = {
	.number		= RPCBVERS_3,
	.nrprocs	= RPCB_HIGHPROC_3,
	.procs		= rpcb_procedures3
};

static struct rpc_version rpcb_version4 = {
	.number		= RPCBVERS_4,
	.nrprocs	= RPCB_HIGHPROC_4,
	.procs		= rpcb_procedures4
};

static struct rpc_version *rpcb_version[] = {
	NULL,
	NULL,
	&rpcb_version2,
	&rpcb_version3,
	&rpcb_version4
};

static struct rpc_stat rpcb_stats;

static struct rpc_program rpcb_program = {
	.name		= "rpcbind",
	.number		= RPCBIND_PROGRAM,
	.nrvers		= ARRAY_SIZE(rpcb_version),
	.version	= rpcb_version,
	.stats		= &rpcb_stats,
};
OpenPOWER on IntegriCloud