rpcb_clnt.c revision 363f724cdd3d2ae554e261be995abdeb15f7bdd9
1/*
2 * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
3 * protocol
4 *
5 * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
6 * RFC 3530: "Network File System (NFS) version 4 Protocol"
7 *
8 * Original: Gilles Quillard, Bull Open Source, 2005 <gilles.quillard@bull.net>
9 * Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
10 *
11 * Descended from net/sunrpc/pmap_clnt.c,
12 *  Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
13 */
14
15#include <linux/module.h>
16
17#include <linux/types.h>
18#include <linux/socket.h>
19#include <linux/in.h>
20#include <linux/in6.h>
21#include <linux/kernel.h>
22#include <linux/errno.h>
23#include <net/ipv6.h>
24
25#include <linux/sunrpc/clnt.h>
26#include <linux/sunrpc/sched.h>
27#include <linux/sunrpc/xprtsock.h>
28
29#ifdef RPC_DEBUG
30# define RPCDBG_FACILITY	RPCDBG_BIND
31#endif
32
33#define RPCBIND_PROGRAM		(100000u)
34#define RPCBIND_PORT		(111u)
35
36#define RPCBVERS_2		(2u)
37#define RPCBVERS_3		(3u)
38#define RPCBVERS_4		(4u)
39
40enum {
41	RPCBPROC_NULL,
42	RPCBPROC_SET,
43	RPCBPROC_UNSET,
44	RPCBPROC_GETPORT,
45	RPCBPROC_GETADDR = 3,		/* alias for GETPORT */
46	RPCBPROC_DUMP,
47	RPCBPROC_CALLIT,
48	RPCBPROC_BCAST = 5,		/* alias for CALLIT */
49	RPCBPROC_GETTIME,
50	RPCBPROC_UADDR2TADDR,
51	RPCBPROC_TADDR2UADDR,
52	RPCBPROC_GETVERSADDR,
53	RPCBPROC_INDIRECT,
54	RPCBPROC_GETADDRLIST,
55	RPCBPROC_GETSTAT,
56};
57
58#define RPCB_HIGHPROC_2		RPCBPROC_CALLIT
59#define RPCB_HIGHPROC_3		RPCBPROC_TADDR2UADDR
60#define RPCB_HIGHPROC_4		RPCBPROC_GETSTAT
61
62/*
63 * r_owner
64 *
65 * The "owner" is allowed to unset a service in the rpcbind database.
66 *
67 * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a
68 * UID which it maps to a local user name via a password lookup.
69 * In all other cases it is ignored.
70 *
71 * For SET/UNSET requests, user space provides a value, even for
72 * network requests, and GETADDR uses an empty string.  We follow
73 * those precedents here.
74 */
75#define RPCB_OWNER_STRING	"0"
76#define RPCB_MAXOWNERLEN	sizeof(RPCB_OWNER_STRING)
77
78static void			rpcb_getport_done(struct rpc_task *, void *);
79static void			rpcb_map_release(void *data);
80static struct rpc_program	rpcb_program;
81
82struct rpcbind_args {
83	struct rpc_xprt *	r_xprt;
84
85	u32			r_prog;
86	u32			r_vers;
87	u32			r_prot;
88	unsigned short		r_port;
89	const char *		r_netid;
90	const char *		r_addr;
91	const char *		r_owner;
92
93	int			r_status;
94};
95
96static struct rpc_procinfo rpcb_procedures2[];
97static struct rpc_procinfo rpcb_procedures3[];
98static struct rpc_procinfo rpcb_procedures4[];
99
100struct rpcb_info {
101	u32			rpc_vers;
102	struct rpc_procinfo *	rpc_proc;
103};
104
105static struct rpcb_info rpcb_next_version[];
106static struct rpcb_info rpcb_next_version6[];
107
108static const struct rpc_call_ops rpcb_getport_ops = {
109	.rpc_call_done		= rpcb_getport_done,
110	.rpc_release		= rpcb_map_release,
111};
112
113static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
114{
115	xprt_clear_binding(xprt);
116	rpc_wake_up_status(&xprt->binding, status);
117}
118
119static void rpcb_map_release(void *data)
120{
121	struct rpcbind_args *map = data;
122
123	rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
124	xprt_put(map->r_xprt);
125	kfree(map);
126}
127
128static const struct sockaddr_in rpcb_inaddr_loopback = {
129	.sin_family		= AF_INET,
130	.sin_addr.s_addr	= htonl(INADDR_LOOPBACK),
131	.sin_port		= htons(RPCBIND_PORT),
132};
133
134static struct rpc_clnt *rpcb_create_local(struct sockaddr *addr,
135					  size_t addrlen, u32 version)
136{
137	struct rpc_create_args args = {
138		.protocol	= XPRT_TRANSPORT_UDP,
139		.address	= addr,
140		.addrsize	= addrlen,
141		.servername	= "localhost",
142		.program	= &rpcb_program,
143		.version	= version,
144		.authflavor	= RPC_AUTH_UNIX,
145		.flags		= RPC_CLNT_CREATE_NOPING,
146	};
147
148	return rpc_create(&args);
149}
150
151static struct rpc_clnt *rpcb_create(char *hostname, struct sockaddr *srvaddr,
152				    size_t salen, int proto, u32 version)
153{
154	struct rpc_create_args args = {
155		.protocol	= proto,
156		.address	= srvaddr,
157		.addrsize	= salen,
158		.servername	= hostname,
159		.program	= &rpcb_program,
160		.version	= version,
161		.authflavor	= RPC_AUTH_UNIX,
162		.flags		= (RPC_CLNT_CREATE_NOPING |
163					RPC_CLNT_CREATE_NONPRIVPORT),
164	};
165
166	switch (srvaddr->sa_family) {
167	case AF_INET:
168		((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
169		break;
170	case AF_INET6:
171		((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
172		break;
173	default:
174		return NULL;
175	}
176
177	return rpc_create(&args);
178}
179
180static int rpcb_register_call(const u32 version, struct rpc_message *msg)
181{
182	struct sockaddr *addr = (struct sockaddr *)&rpcb_inaddr_loopback;
183	size_t addrlen = sizeof(rpcb_inaddr_loopback);
184	struct rpc_clnt *rpcb_clnt;
185	int result, error = 0;
186
187	msg->rpc_resp = &result;
188
189	rpcb_clnt = rpcb_create_local(addr, addrlen, version);
190	if (!IS_ERR(rpcb_clnt)) {
191		error = rpc_call_sync(rpcb_clnt, msg, 0);
192		rpc_shutdown_client(rpcb_clnt);
193	} else
194		error = PTR_ERR(rpcb_clnt);
195
196	if (error < 0) {
197		dprintk("RPC:       failed to contact local rpcbind "
198				"server (errno %d).\n", -error);
199		return error;
200	}
201
202	if (!result)
203		return -EACCES;
204	return 0;
205}
206
207/**
208 * rpcb_register - set or unset a port registration with the local rpcbind svc
209 * @prog: RPC program number to bind
210 * @vers: RPC version number to bind
211 * @prot: transport protocol to register
212 * @port: port value to register
213 *
214 * Returns zero if the registration request was dispatched successfully
215 * and the rpcbind daemon returned success.  Otherwise, returns an errno
216 * value that reflects the nature of the error (request could not be
217 * dispatched, timed out, or rpcbind returned an error).
218 *
219 * RPC services invoke this function to advertise their contact
220 * information via the system's rpcbind daemon.  RPC services
221 * invoke this function once for each [program, version, transport]
222 * tuple they wish to advertise.
223 *
224 * Callers may also unregister RPC services that are no longer
225 * available by setting the passed-in port to zero.  This removes
226 * all registered transports for [program, version] from the local
227 * rpcbind database.
228 *
229 * This function uses rpcbind protocol version 2 to contact the
230 * local rpcbind daemon.
231 *
232 * Registration works over both AF_INET and AF_INET6, and services
233 * registered via this function are advertised as available for any
234 * address.  If the local rpcbind daemon is listening on AF_INET6,
235 * services registered via this function will be advertised on
236 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
237 * addresses).
238 */
239int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port)
240{
241	struct rpcbind_args map = {
242		.r_prog		= prog,
243		.r_vers		= vers,
244		.r_prot		= prot,
245		.r_port		= port,
246	};
247	struct rpc_message msg = {
248		.rpc_argp	= &map,
249	};
250
251	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
252			"rpcbind\n", (port ? "" : "un"),
253			prog, vers, prot, port);
254
255	msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
256	if (port)
257		msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];
258
259	return rpcb_register_call(RPCBVERS_2, &msg);
260}
261
262/*
263 * Fill in AF_INET family-specific arguments to register
264 */
265static int rpcb_register_inet4(const struct sockaddr *sap,
266			       struct rpc_message *msg)
267{
268	const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
269	struct rpcbind_args *map = msg->rpc_argp;
270	unsigned short port = ntohs(sin->sin_port);
271	char buf[32];
272
273	/* Construct AF_INET universal address */
274	snprintf(buf, sizeof(buf), "%pI4.%u.%u",
275		 &sin->sin_addr.s_addr, port >> 8, port & 0xff);
276	map->r_addr = buf;
277
278	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
279		"local rpcbind\n", (port ? "" : "un"),
280			map->r_prog, map->r_vers,
281			map->r_addr, map->r_netid);
282
283	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
284	if (port)
285		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
286
287	return rpcb_register_call(RPCBVERS_4, msg);
288}
289
290/*
291 * Fill in AF_INET6 family-specific arguments to register
292 */
293static int rpcb_register_inet6(const struct sockaddr *sap,
294			       struct rpc_message *msg)
295{
296	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
297	struct rpcbind_args *map = msg->rpc_argp;
298	unsigned short port = ntohs(sin6->sin6_port);
299	char buf[64];
300
301	/* Construct AF_INET6 universal address */
302	if (ipv6_addr_any(&sin6->sin6_addr))
303		snprintf(buf, sizeof(buf), "::.%u.%u",
304				port >> 8, port & 0xff);
305	else
306		snprintf(buf, sizeof(buf), "%pI6.%u.%u",
307			 &sin6->sin6_addr, port >> 8, port & 0xff);
308	map->r_addr = buf;
309
310	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
311		"local rpcbind\n", (port ? "" : "un"),
312			map->r_prog, map->r_vers,
313			map->r_addr, map->r_netid);
314
315	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
316	if (port)
317		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
318
319	return rpcb_register_call(RPCBVERS_4, msg);
320}
321
322static int rpcb_unregister_all_protofamilies(struct rpc_message *msg)
323{
324	struct rpcbind_args *map = msg->rpc_argp;
325
326	dprintk("RPC:       unregistering [%u, %u, '%s'] with "
327		"local rpcbind\n",
328			map->r_prog, map->r_vers, map->r_netid);
329
330	map->r_addr = "";
331	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
332
333	return rpcb_register_call(RPCBVERS_4, msg);
334}
335
336/**
337 * rpcb_v4_register - set or unset a port registration with the local rpcbind
338 * @program: RPC program number of service to (un)register
339 * @version: RPC version number of service to (un)register
340 * @address: address family, IP address, and port to (un)register
341 * @netid: netid of transport protocol to (un)register
342 *
343 * Returns zero if the registration request was dispatched successfully
344 * and the rpcbind daemon returned success.  Otherwise, returns an errno
345 * value that reflects the nature of the error (request could not be
346 * dispatched, timed out, or rpcbind returned an error).
347 *
348 * RPC services invoke this function to advertise their contact
349 * information via the system's rpcbind daemon.  RPC services
350 * invoke this function once for each [program, version, address,
351 * netid] tuple they wish to advertise.
352 *
353 * Callers may also unregister RPC services that are registered at a
354 * specific address by setting the port number in @address to zero.
355 * They may unregister all registered protocol families at once for
356 * a service by passing a NULL @address argument.  If @netid is ""
357 * then all netids for [program, version, address] are unregistered.
358 *
359 * This function uses rpcbind protocol version 4 to contact the
360 * local rpcbind daemon.  The local rpcbind daemon must support
361 * version 4 of the rpcbind protocol in order for these functions
362 * to register a service successfully.
363 *
364 * Supported netids include "udp" and "tcp" for UDP and TCP over
365 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
366 * respectively.
367 *
368 * The contents of @address determine the address family and the
369 * port to be registered.  The usual practice is to pass INADDR_ANY
370 * as the raw address, but specifying a non-zero address is also
371 * supported by this API if the caller wishes to advertise an RPC
372 * service on a specific network interface.
373 *
374 * Note that passing in INADDR_ANY does not create the same service
375 * registration as IN6ADDR_ANY.  The former advertises an RPC
376 * service on any IPv4 address, but not on IPv6.  The latter
377 * advertises the service on all IPv4 and IPv6 addresses.
378 */
379int rpcb_v4_register(const u32 program, const u32 version,
380		     const struct sockaddr *address, const char *netid)
381{
382	struct rpcbind_args map = {
383		.r_prog		= program,
384		.r_vers		= version,
385		.r_netid	= netid,
386		.r_owner	= RPCB_OWNER_STRING,
387	};
388	struct rpc_message msg = {
389		.rpc_argp	= &map,
390	};
391
392	if (address == NULL)
393		return rpcb_unregister_all_protofamilies(&msg);
394
395	switch (address->sa_family) {
396	case AF_INET:
397		return rpcb_register_inet4(address, &msg);
398	case AF_INET6:
399		return rpcb_register_inet6(address, &msg);
400	}
401
402	return -EAFNOSUPPORT;
403}
404
405/**
406 * rpcb_getport_sync - obtain the port for an RPC service on a given host
407 * @sin: address of remote peer
408 * @prog: RPC program number to bind
409 * @vers: RPC version number to bind
410 * @prot: transport protocol to use to make this request
411 *
412 * Return value is the requested advertised port number,
413 * or a negative errno value.
414 *
415 * Called from outside the RPC client in a synchronous task context.
416 * Uses default timeout parameters specified by underlying transport.
417 *
418 * XXX: Needs to support IPv6
419 */
420int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
421{
422	struct rpcbind_args map = {
423		.r_prog		= prog,
424		.r_vers		= vers,
425		.r_prot		= prot,
426		.r_port		= 0,
427	};
428	struct rpc_message msg = {
429		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
430		.rpc_argp	= &map,
431		.rpc_resp	= &map.r_port,
432	};
433	struct rpc_clnt	*rpcb_clnt;
434	int status;
435
436	dprintk("RPC:       %s(%pI4, %u, %u, %d)\n",
437		__func__, &sin->sin_addr.s_addr, prog, vers, prot);
438
439	rpcb_clnt = rpcb_create(NULL, (struct sockaddr *)sin,
440				sizeof(*sin), prot, RPCBVERS_2);
441	if (IS_ERR(rpcb_clnt))
442		return PTR_ERR(rpcb_clnt);
443
444	status = rpc_call_sync(rpcb_clnt, &msg, 0);
445	rpc_shutdown_client(rpcb_clnt);
446
447	if (status >= 0) {
448		if (map.r_port != 0)
449			return map.r_port;
450		status = -EACCES;
451	}
452	return status;
453}
454EXPORT_SYMBOL_GPL(rpcb_getport_sync);
455
456static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
457{
458	struct rpc_message msg = {
459		.rpc_proc = proc,
460		.rpc_argp = map,
461		.rpc_resp = &map->r_port,
462	};
463	struct rpc_task_setup task_setup_data = {
464		.rpc_client = rpcb_clnt,
465		.rpc_message = &msg,
466		.callback_ops = &rpcb_getport_ops,
467		.callback_data = map,
468		.flags = RPC_TASK_ASYNC,
469	};
470
471	return rpc_run_task(&task_setup_data);
472}
473
474/*
475 * In the case where rpc clients have been cloned, we want to make
476 * sure that we use the program number/version etc of the actual
477 * owner of the xprt. To do so, we walk back up the tree of parents
478 * to find whoever created the transport and/or whoever has the
479 * autobind flag set.
480 */
481static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
482{
483	struct rpc_clnt *parent = clnt->cl_parent;
484
485	while (parent != clnt) {
486		if (parent->cl_xprt != clnt->cl_xprt)
487			break;
488		if (clnt->cl_autobind)
489			break;
490		clnt = parent;
491		parent = parent->cl_parent;
492	}
493	return clnt;
494}
495
496/**
497 * rpcb_getport_async - obtain the port for a given RPC service on a given host
498 * @task: task that is waiting for portmapper request
499 *
500 * This one can be called for an ongoing RPC request, and can be used in
501 * an async (rpciod) context.
502 */
503void rpcb_getport_async(struct rpc_task *task)
504{
505	struct rpc_clnt *clnt;
506	struct rpc_procinfo *proc;
507	u32 bind_version;
508	struct rpc_xprt *xprt;
509	struct rpc_clnt	*rpcb_clnt;
510	static struct rpcbind_args *map;
511	struct rpc_task	*child;
512	struct sockaddr_storage addr;
513	struct sockaddr *sap = (struct sockaddr *)&addr;
514	size_t salen;
515	int status;
516
517	clnt = rpcb_find_transport_owner(task->tk_client);
518	xprt = clnt->cl_xprt;
519
520	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
521		task->tk_pid, __func__,
522		clnt->cl_server, clnt->cl_prog, clnt->cl_vers, xprt->prot);
523
524	/* Put self on the wait queue to ensure we get notified if
525	 * some other task is already attempting to bind the port */
526	rpc_sleep_on(&xprt->binding, task, NULL);
527
528	if (xprt_test_and_set_binding(xprt)) {
529		dprintk("RPC: %5u %s: waiting for another binder\n",
530			task->tk_pid, __func__);
531		return;
532	}
533
534	/* Someone else may have bound if we slept */
535	if (xprt_bound(xprt)) {
536		status = 0;
537		dprintk("RPC: %5u %s: already bound\n",
538			task->tk_pid, __func__);
539		goto bailout_nofree;
540	}
541
542	salen = rpc_peeraddr(clnt, sap, sizeof(addr));
543
544	/* Don't ever use rpcbind v2 for AF_INET6 requests */
545	switch (sap->sa_family) {
546	case AF_INET:
547		proc = rpcb_next_version[xprt->bind_index].rpc_proc;
548		bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
549		break;
550	case AF_INET6:
551		proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
552		bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
553		break;
554	default:
555		status = -EAFNOSUPPORT;
556		dprintk("RPC: %5u %s: bad address family\n",
557				task->tk_pid, __func__);
558		goto bailout_nofree;
559	}
560	if (proc == NULL) {
561		xprt->bind_index = 0;
562		status = -EPFNOSUPPORT;
563		dprintk("RPC: %5u %s: no more getport versions available\n",
564			task->tk_pid, __func__);
565		goto bailout_nofree;
566	}
567
568	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
569		task->tk_pid, __func__, bind_version);
570
571	rpcb_clnt = rpcb_create(clnt->cl_server, sap, salen, xprt->prot,
572				bind_version);
573	if (IS_ERR(rpcb_clnt)) {
574		status = PTR_ERR(rpcb_clnt);
575		dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
576			task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
577		goto bailout_nofree;
578	}
579
580	map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
581	if (!map) {
582		status = -ENOMEM;
583		dprintk("RPC: %5u %s: no memory available\n",
584			task->tk_pid, __func__);
585		goto bailout_release_client;
586	}
587	map->r_prog = clnt->cl_prog;
588	map->r_vers = clnt->cl_vers;
589	map->r_prot = xprt->prot;
590	map->r_port = 0;
591	map->r_xprt = xprt_get(xprt);
592	map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
593	map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
594	map->r_owner = "";
595	map->r_status = -EIO;
596
597	child = rpcb_call_async(rpcb_clnt, map, proc);
598	rpc_release_client(rpcb_clnt);
599	if (IS_ERR(child)) {
600		/* rpcb_map_release() has freed the arguments */
601		dprintk("RPC: %5u %s: rpc_run_task failed\n",
602			task->tk_pid, __func__);
603		return;
604	}
605
606	xprt->stat.bind_count++;
607	rpc_put_task(child);
608	return;
609
610bailout_release_client:
611	rpc_release_client(rpcb_clnt);
612bailout_nofree:
613	rpcb_wake_rpcbind_waiters(xprt, status);
614	task->tk_status = status;
615}
616EXPORT_SYMBOL_GPL(rpcb_getport_async);
617
618/*
619 * Rpcbind child task calls this callback via tk_exit.
620 */
621static void rpcb_getport_done(struct rpc_task *child, void *data)
622{
623	struct rpcbind_args *map = data;
624	struct rpc_xprt *xprt = map->r_xprt;
625	int status = child->tk_status;
626
627	/* Garbage reply: retry with a lesser rpcbind version */
628	if (status == -EIO)
629		status = -EPROTONOSUPPORT;
630
631	/* rpcbind server doesn't support this rpcbind protocol version */
632	if (status == -EPROTONOSUPPORT)
633		xprt->bind_index++;
634
635	if (status < 0) {
636		/* rpcbind server not available on remote host? */
637		xprt->ops->set_port(xprt, 0);
638	} else if (map->r_port == 0) {
639		/* Requested RPC service wasn't registered on remote host */
640		xprt->ops->set_port(xprt, 0);
641		status = -EACCES;
642	} else {
643		/* Succeeded */
644		xprt->ops->set_port(xprt, map->r_port);
645		xprt_set_bound(xprt);
646		status = 0;
647	}
648
649	dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
650			child->tk_pid, status, map->r_port);
651
652	map->r_status = status;
653}
654
655/*
656 * XDR functions for rpcbind
657 */
658
659static int rpcb_encode_mapping(struct rpc_rqst *req, __be32 *p,
660			       struct rpcbind_args *rpcb)
661{
662	dprintk("RPC:       encoding rpcb request (%u, %u, %d, %u)\n",
663			rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
664	*p++ = htonl(rpcb->r_prog);
665	*p++ = htonl(rpcb->r_vers);
666	*p++ = htonl(rpcb->r_prot);
667	*p++ = htonl(rpcb->r_port);
668
669	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
670	return 0;
671}
672
673static int rpcb_decode_getport(struct rpc_rqst *req, __be32 *p,
674			       unsigned short *portp)
675{
676	*portp = (unsigned short) ntohl(*p++);
677	dprintk("RPC:       rpcb getport result: %u\n",
678			*portp);
679	return 0;
680}
681
682static int rpcb_decode_set(struct rpc_rqst *req, __be32 *p,
683			   unsigned int *boolp)
684{
685	*boolp = (unsigned int) ntohl(*p++);
686	dprintk("RPC:       rpcb set/unset call %s\n",
687			(*boolp ? "succeeded" : "failed"));
688	return 0;
689}
690
691static int rpcb_encode_getaddr(struct rpc_rqst *req, __be32 *p,
692			       struct rpcbind_args *rpcb)
693{
694	dprintk("RPC:       encoding rpcb request (%u, %u, %s)\n",
695			rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
696	*p++ = htonl(rpcb->r_prog);
697	*p++ = htonl(rpcb->r_vers);
698
699	p = xdr_encode_string(p, rpcb->r_netid);
700	p = xdr_encode_string(p, rpcb->r_addr);
701	p = xdr_encode_string(p, rpcb->r_owner);
702
703	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
704
705	return 0;
706}
707
708static int rpcb_decode_getaddr(struct rpc_rqst *req, __be32 *p,
709			       unsigned short *portp)
710{
711	char *addr;
712	u32 addr_len;
713	int c, i, f, first, val;
714
715	*portp = 0;
716	addr_len = ntohl(*p++);
717
718	if (addr_len == 0) {
719		dprintk("RPC:       rpcb_decode_getaddr: "
720					"service is not registered\n");
721		return 0;
722	}
723
724	/*
725	 * Simple sanity check.
726	 */
727	if (addr_len > RPCBIND_MAXUADDRLEN)
728		goto out_err;
729
730	/*
731	 * Start at the end and walk backwards until the first dot
732	 * is encountered.  When the second dot is found, we have
733	 * both parts of the port number.
734	 */
735	addr = (char *)p;
736	val = 0;
737	first = 1;
738	f = 1;
739	for (i = addr_len - 1; i > 0; i--) {
740		c = addr[i];
741		if (c >= '0' && c <= '9') {
742			val += (c - '0') * f;
743			f *= 10;
744		} else if (c == '.') {
745			if (first) {
746				*portp = val;
747				val = first = 0;
748				f = 1;
749			} else {
750				*portp |= (val << 8);
751				break;
752			}
753		}
754	}
755
756	/*
757	 * Simple sanity check.  If we never saw a dot in the reply,
758	 * then this was probably just garbage.
759	 */
760	if (first)
761		goto out_err;
762
763	dprintk("RPC:       rpcb_decode_getaddr port=%u\n", *portp);
764	return 0;
765
766out_err:
767	dprintk("RPC:       rpcbind server returned malformed reply\n");
768	return -EIO;
769}
770
771#define RPCB_program_sz		(1u)
772#define RPCB_version_sz		(1u)
773#define RPCB_protocol_sz	(1u)
774#define RPCB_port_sz		(1u)
775#define RPCB_boolean_sz		(1u)
776
777#define RPCB_netid_sz		(1+XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
778#define RPCB_addr_sz		(1+XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
779#define RPCB_ownerstring_sz	(1+XDR_QUADLEN(RPCB_MAXOWNERLEN))
780
781#define RPCB_mappingargs_sz	RPCB_program_sz+RPCB_version_sz+	\
782				RPCB_protocol_sz+RPCB_port_sz
783#define RPCB_getaddrargs_sz	RPCB_program_sz+RPCB_version_sz+	\
784				RPCB_netid_sz+RPCB_addr_sz+		\
785				RPCB_ownerstring_sz
786
787#define RPCB_setres_sz		RPCB_boolean_sz
788#define RPCB_getportres_sz	RPCB_port_sz
789
790/*
791 * Note that RFC 1833 does not put any size restrictions on the
792 * address string returned by the remote rpcbind database.
793 */
794#define RPCB_getaddrres_sz	RPCB_addr_sz
795
796#define PROC(proc, argtype, restype)					\
797	[RPCBPROC_##proc] = {						\
798		.p_proc		= RPCBPROC_##proc,			\
799		.p_encode	= (kxdrproc_t) rpcb_encode_##argtype,	\
800		.p_decode	= (kxdrproc_t) rpcb_decode_##restype,	\
801		.p_arglen	= RPCB_##argtype##args_sz,		\
802		.p_replen	= RPCB_##restype##res_sz,		\
803		.p_statidx	= RPCBPROC_##proc,			\
804		.p_timer	= 0,					\
805		.p_name		= #proc,				\
806	}
807
808/*
809 * Not all rpcbind procedures described in RFC 1833 are implemented
810 * since the Linux kernel RPC code requires only these.
811 */
812static struct rpc_procinfo rpcb_procedures2[] = {
813	PROC(SET,		mapping,	set),
814	PROC(UNSET,		mapping,	set),
815	PROC(GETPORT,		mapping,	getport),
816};
817
818static struct rpc_procinfo rpcb_procedures3[] = {
819	PROC(SET,		getaddr,	set),
820	PROC(UNSET,		getaddr,	set),
821	PROC(GETADDR,		getaddr,	getaddr),
822};
823
824static struct rpc_procinfo rpcb_procedures4[] = {
825	PROC(SET,		getaddr,	set),
826	PROC(UNSET,		getaddr,	set),
827	PROC(GETADDR,		getaddr,	getaddr),
828	PROC(GETVERSADDR,	getaddr,	getaddr),
829};
830
831static struct rpcb_info rpcb_next_version[] = {
832	{
833		.rpc_vers	= RPCBVERS_2,
834		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
835	},
836	{
837		.rpc_proc	= NULL,
838	},
839};
840
841static struct rpcb_info rpcb_next_version6[] = {
842	{
843		.rpc_vers	= RPCBVERS_4,
844		.rpc_proc	= &rpcb_procedures4[RPCBPROC_GETADDR],
845	},
846	{
847		.rpc_vers	= RPCBVERS_3,
848		.rpc_proc	= &rpcb_procedures3[RPCBPROC_GETADDR],
849	},
850	{
851		.rpc_proc	= NULL,
852	},
853};
854
855static struct rpc_version rpcb_version2 = {
856	.number		= RPCBVERS_2,
857	.nrprocs	= RPCB_HIGHPROC_2,
858	.procs		= rpcb_procedures2
859};
860
861static struct rpc_version rpcb_version3 = {
862	.number		= RPCBVERS_3,
863	.nrprocs	= RPCB_HIGHPROC_3,
864	.procs		= rpcb_procedures3
865};
866
867static struct rpc_version rpcb_version4 = {
868	.number		= RPCBVERS_4,
869	.nrprocs	= RPCB_HIGHPROC_4,
870	.procs		= rpcb_procedures4
871};
872
873static struct rpc_version *rpcb_version[] = {
874	NULL,
875	NULL,
876	&rpcb_version2,
877	&rpcb_version3,
878	&rpcb_version4
879};
880
881static struct rpc_stat rpcb_stats;
882
883static struct rpc_program rpcb_program = {
884	.name		= "rpcbind",
885	.number		= RPCBIND_PROGRAM,
886	.nrvers		= ARRAY_SIZE(rpcb_version),
887	.version	= rpcb_version,
888	.stats		= &rpcb_stats,
889};
890