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v4.6
 
   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/un.h>
  20#include <linux/in.h>
  21#include <linux/in6.h>
  22#include <linux/kernel.h>
  23#include <linux/errno.h>
  24#include <linux/mutex.h>
  25#include <linux/slab.h>
  26#include <net/ipv6.h>
  27
  28#include <linux/sunrpc/clnt.h>
  29#include <linux/sunrpc/addr.h>
  30#include <linux/sunrpc/sched.h>
  31#include <linux/sunrpc/xprtsock.h>
  32
  33#include "netns.h"
  34
  35#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  36# define RPCDBG_FACILITY	RPCDBG_BIND
  37#endif
  38
  39#define RPCBIND_SOCK_PATHNAME	"/var/run/rpcbind.sock"
  40
  41#define RPCBIND_PROGRAM		(100000u)
  42#define RPCBIND_PORT		(111u)
  43
  44#define RPCBVERS_2		(2u)
  45#define RPCBVERS_3		(3u)
  46#define RPCBVERS_4		(4u)
  47
  48enum {
  49	RPCBPROC_NULL,
  50	RPCBPROC_SET,
  51	RPCBPROC_UNSET,
  52	RPCBPROC_GETPORT,
  53	RPCBPROC_GETADDR = 3,		/* alias for GETPORT */
  54	RPCBPROC_DUMP,
  55	RPCBPROC_CALLIT,
  56	RPCBPROC_BCAST = 5,		/* alias for CALLIT */
  57	RPCBPROC_GETTIME,
  58	RPCBPROC_UADDR2TADDR,
  59	RPCBPROC_TADDR2UADDR,
  60	RPCBPROC_GETVERSADDR,
  61	RPCBPROC_INDIRECT,
  62	RPCBPROC_GETADDRLIST,
  63	RPCBPROC_GETSTAT,
  64};
  65
  66/*
  67 * r_owner
  68 *
  69 * The "owner" is allowed to unset a service in the rpcbind database.
  70 *
  71 * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a
  72 * UID which it maps to a local user name via a password lookup.
  73 * In all other cases it is ignored.
  74 *
  75 * For SET/UNSET requests, user space provides a value, even for
  76 * network requests, and GETADDR uses an empty string.  We follow
  77 * those precedents here.
  78 */
  79#define RPCB_OWNER_STRING	"0"
  80#define RPCB_MAXOWNERLEN	sizeof(RPCB_OWNER_STRING)
  81
  82/*
  83 * XDR data type sizes
  84 */
  85#define RPCB_program_sz		(1)
  86#define RPCB_version_sz		(1)
  87#define RPCB_protocol_sz	(1)
  88#define RPCB_port_sz		(1)
  89#define RPCB_boolean_sz		(1)
  90
  91#define RPCB_netid_sz		(1 + XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
  92#define RPCB_addr_sz		(1 + XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
  93#define RPCB_ownerstring_sz	(1 + XDR_QUADLEN(RPCB_MAXOWNERLEN))
  94
  95/*
  96 * XDR argument and result sizes
  97 */
  98#define RPCB_mappingargs_sz	(RPCB_program_sz + RPCB_version_sz + \
  99				RPCB_protocol_sz + RPCB_port_sz)
 100#define RPCB_getaddrargs_sz	(RPCB_program_sz + RPCB_version_sz + \
 101				RPCB_netid_sz + RPCB_addr_sz + \
 102				RPCB_ownerstring_sz)
 103
 104#define RPCB_getportres_sz	RPCB_port_sz
 105#define RPCB_setres_sz		RPCB_boolean_sz
 106
 107/*
 108 * Note that RFC 1833 does not put any size restrictions on the
 109 * address string returned by the remote rpcbind database.
 110 */
 111#define RPCB_getaddrres_sz	RPCB_addr_sz
 112
 113static void			rpcb_getport_done(struct rpc_task *, void *);
 114static void			rpcb_map_release(void *data);
 115static const struct rpc_program	rpcb_program;
 116
 117struct rpcbind_args {
 118	struct rpc_xprt *	r_xprt;
 119
 120	u32			r_prog;
 121	u32			r_vers;
 122	u32			r_prot;
 123	unsigned short		r_port;
 124	const char *		r_netid;
 125	const char *		r_addr;
 126	const char *		r_owner;
 127
 128	int			r_status;
 129};
 130
 131static struct rpc_procinfo rpcb_procedures2[];
 132static struct rpc_procinfo rpcb_procedures3[];
 133static struct rpc_procinfo rpcb_procedures4[];
 134
 135struct rpcb_info {
 136	u32			rpc_vers;
 137	struct rpc_procinfo *	rpc_proc;
 138};
 139
 140static const struct rpcb_info rpcb_next_version[];
 141static const struct rpcb_info rpcb_next_version6[];
 142
 143static const struct rpc_call_ops rpcb_getport_ops = {
 144	.rpc_call_done		= rpcb_getport_done,
 145	.rpc_release		= rpcb_map_release,
 146};
 147
 148static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
 149{
 150	xprt_clear_binding(xprt);
 151	rpc_wake_up_status(&xprt->binding, status);
 152}
 153
 154static void rpcb_map_release(void *data)
 155{
 156	struct rpcbind_args *map = data;
 157
 158	rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
 159	xprt_put(map->r_xprt);
 160	kfree(map->r_addr);
 161	kfree(map);
 162}
 163
 164static int rpcb_get_local(struct net *net)
 165{
 166	int cnt;
 167	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 168
 169	spin_lock(&sn->rpcb_clnt_lock);
 170	if (sn->rpcb_users)
 171		sn->rpcb_users++;
 172	cnt = sn->rpcb_users;
 173	spin_unlock(&sn->rpcb_clnt_lock);
 174
 175	return cnt;
 176}
 177
 178void rpcb_put_local(struct net *net)
 179{
 180	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 181	struct rpc_clnt *clnt = sn->rpcb_local_clnt;
 182	struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4;
 183	int shutdown = 0;
 184
 185	spin_lock(&sn->rpcb_clnt_lock);
 186	if (sn->rpcb_users) {
 187		if (--sn->rpcb_users == 0) {
 188			sn->rpcb_local_clnt = NULL;
 189			sn->rpcb_local_clnt4 = NULL;
 190		}
 191		shutdown = !sn->rpcb_users;
 192	}
 193	spin_unlock(&sn->rpcb_clnt_lock);
 194
 195	if (shutdown) {
 196		/*
 197		 * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
 198		 */
 199		if (clnt4)
 200			rpc_shutdown_client(clnt4);
 201		if (clnt)
 202			rpc_shutdown_client(clnt);
 203	}
 204}
 205
 206static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt,
 207			struct rpc_clnt *clnt4,
 208			bool is_af_local)
 209{
 210	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 211
 212	/* Protected by rpcb_create_local_mutex */
 213	sn->rpcb_local_clnt = clnt;
 214	sn->rpcb_local_clnt4 = clnt4;
 215	sn->rpcb_is_af_local = is_af_local ? 1 : 0;
 216	smp_wmb(); 
 217	sn->rpcb_users = 1;
 218	dprintk("RPC:       created new rpcb local clients (rpcb_local_clnt: "
 219			"%p, rpcb_local_clnt4: %p) for net %p%s\n",
 220			sn->rpcb_local_clnt, sn->rpcb_local_clnt4,
 221			net, (net == &init_net) ? " (init_net)" : "");
 222}
 223
 224/*
 225 * Returns zero on success, otherwise a negative errno value
 226 * is returned.
 227 */
 228static int rpcb_create_local_unix(struct net *net)
 229{
 230	static const struct sockaddr_un rpcb_localaddr_rpcbind = {
 231		.sun_family		= AF_LOCAL,
 232		.sun_path		= RPCBIND_SOCK_PATHNAME,
 233	};
 234	struct rpc_create_args args = {
 235		.net		= net,
 236		.protocol	= XPRT_TRANSPORT_LOCAL,
 237		.address	= (struct sockaddr *)&rpcb_localaddr_rpcbind,
 238		.addrsize	= sizeof(rpcb_localaddr_rpcbind),
 239		.servername	= "localhost",
 240		.program	= &rpcb_program,
 241		.version	= RPCBVERS_2,
 242		.authflavor	= RPC_AUTH_NULL,
 
 243		/*
 244		 * We turn off the idle timeout to prevent the kernel
 245		 * from automatically disconnecting the socket.
 246		 * Otherwise, we'd have to cache the mount namespace
 247		 * of the caller and somehow pass that to the socket
 248		 * reconnect code.
 249		 */
 250		.flags		= RPC_CLNT_CREATE_NO_IDLE_TIMEOUT,
 251	};
 252	struct rpc_clnt *clnt, *clnt4;
 253	int result = 0;
 254
 255	/*
 256	 * Because we requested an RPC PING at transport creation time,
 257	 * this works only if the user space portmapper is rpcbind, and
 258	 * it's listening on AF_LOCAL on the named socket.
 259	 */
 260	clnt = rpc_create(&args);
 261	if (IS_ERR(clnt)) {
 262		dprintk("RPC:       failed to create AF_LOCAL rpcbind "
 263				"client (errno %ld).\n", PTR_ERR(clnt));
 264		result = PTR_ERR(clnt);
 265		goto out;
 266	}
 267
 268	clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 269	if (IS_ERR(clnt4)) {
 270		dprintk("RPC:       failed to bind second program to "
 271				"rpcbind v4 client (errno %ld).\n",
 272				PTR_ERR(clnt4));
 273		clnt4 = NULL;
 274	}
 275
 276	rpcb_set_local(net, clnt, clnt4, true);
 277
 278out:
 279	return result;
 280}
 281
 282/*
 283 * Returns zero on success, otherwise a negative errno value
 284 * is returned.
 285 */
 286static int rpcb_create_local_net(struct net *net)
 287{
 288	static const struct sockaddr_in rpcb_inaddr_loopback = {
 289		.sin_family		= AF_INET,
 290		.sin_addr.s_addr	= htonl(INADDR_LOOPBACK),
 291		.sin_port		= htons(RPCBIND_PORT),
 292	};
 293	struct rpc_create_args args = {
 294		.net		= net,
 295		.protocol	= XPRT_TRANSPORT_TCP,
 296		.address	= (struct sockaddr *)&rpcb_inaddr_loopback,
 297		.addrsize	= sizeof(rpcb_inaddr_loopback),
 298		.servername	= "localhost",
 299		.program	= &rpcb_program,
 300		.version	= RPCBVERS_2,
 301		.authflavor	= RPC_AUTH_UNIX,
 
 302		.flags		= RPC_CLNT_CREATE_NOPING,
 303	};
 304	struct rpc_clnt *clnt, *clnt4;
 305	int result = 0;
 306
 307	clnt = rpc_create(&args);
 308	if (IS_ERR(clnt)) {
 309		dprintk("RPC:       failed to create local rpcbind "
 310				"client (errno %ld).\n", PTR_ERR(clnt));
 311		result = PTR_ERR(clnt);
 312		goto out;
 313	}
 314
 315	/*
 316	 * This results in an RPC ping.  On systems running portmapper,
 317	 * the v4 ping will fail.  Proceed anyway, but disallow rpcb
 318	 * v4 upcalls.
 319	 */
 320	clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 321	if (IS_ERR(clnt4)) {
 322		dprintk("RPC:       failed to bind second program to "
 323				"rpcbind v4 client (errno %ld).\n",
 324				PTR_ERR(clnt4));
 325		clnt4 = NULL;
 326	}
 327
 328	rpcb_set_local(net, clnt, clnt4, false);
 329
 330out:
 331	return result;
 332}
 333
 334/*
 335 * Returns zero on success, otherwise a negative errno value
 336 * is returned.
 337 */
 338int rpcb_create_local(struct net *net)
 339{
 340	static DEFINE_MUTEX(rpcb_create_local_mutex);
 341	int result = 0;
 342
 343	if (rpcb_get_local(net))
 344		return result;
 345
 346	mutex_lock(&rpcb_create_local_mutex);
 347	if (rpcb_get_local(net))
 348		goto out;
 349
 350	if (rpcb_create_local_unix(net) != 0)
 351		result = rpcb_create_local_net(net);
 352
 353out:
 354	mutex_unlock(&rpcb_create_local_mutex);
 355	return result;
 356}
 357
 358static struct rpc_clnt *rpcb_create(struct net *net, const char *nodename,
 359				    const char *hostname,
 360				    struct sockaddr *srvaddr, size_t salen,
 361				    int proto, u32 version)
 
 
 362{
 363	struct rpc_create_args args = {
 364		.net		= net,
 365		.protocol	= proto,
 366		.address	= srvaddr,
 367		.addrsize	= salen,
 
 368		.servername	= hostname,
 369		.nodename	= nodename,
 370		.program	= &rpcb_program,
 371		.version	= version,
 372		.authflavor	= RPC_AUTH_UNIX,
 
 373		.flags		= (RPC_CLNT_CREATE_NOPING |
 374					RPC_CLNT_CREATE_NONPRIVPORT),
 375	};
 376
 377	switch (srvaddr->sa_family) {
 378	case AF_INET:
 379		((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
 380		break;
 381	case AF_INET6:
 382		((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
 383		break;
 384	default:
 385		return ERR_PTR(-EAFNOSUPPORT);
 386	}
 387
 388	return rpc_create(&args);
 389}
 390
 391static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set)
 392{
 393	int flags = RPC_TASK_NOCONNECT;
 394	int error, result = 0;
 395
 396	if (is_set || !sn->rpcb_is_af_local)
 397		flags = RPC_TASK_SOFTCONN;
 398	msg->rpc_resp = &result;
 399
 400	error = rpc_call_sync(clnt, msg, flags);
 401	if (error < 0) {
 402		dprintk("RPC:       failed to contact local rpcbind "
 403				"server (errno %d).\n", -error);
 404		return error;
 405	}
 406
 407	if (!result)
 408		return -EACCES;
 409	return 0;
 410}
 411
 412/**
 413 * rpcb_register - set or unset a port registration with the local rpcbind svc
 414 * @net: target network namespace
 415 * @prog: RPC program number to bind
 416 * @vers: RPC version number to bind
 417 * @prot: transport protocol to register
 418 * @port: port value to register
 419 *
 420 * Returns zero if the registration request was dispatched successfully
 421 * and the rpcbind daemon returned success.  Otherwise, returns an errno
 422 * value that reflects the nature of the error (request could not be
 423 * dispatched, timed out, or rpcbind returned an error).
 424 *
 425 * RPC services invoke this function to advertise their contact
 426 * information via the system's rpcbind daemon.  RPC services
 427 * invoke this function once for each [program, version, transport]
 428 * tuple they wish to advertise.
 429 *
 430 * Callers may also unregister RPC services that are no longer
 431 * available by setting the passed-in port to zero.  This removes
 432 * all registered transports for [program, version] from the local
 433 * rpcbind database.
 434 *
 435 * This function uses rpcbind protocol version 2 to contact the
 436 * local rpcbind daemon.
 437 *
 438 * Registration works over both AF_INET and AF_INET6, and services
 439 * registered via this function are advertised as available for any
 440 * address.  If the local rpcbind daemon is listening on AF_INET6,
 441 * services registered via this function will be advertised on
 442 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
 443 * addresses).
 444 */
 445int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port)
 446{
 447	struct rpcbind_args map = {
 448		.r_prog		= prog,
 449		.r_vers		= vers,
 450		.r_prot		= prot,
 451		.r_port		= port,
 452	};
 453	struct rpc_message msg = {
 454		.rpc_argp	= &map,
 455	};
 456	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 457	bool is_set = false;
 458
 459	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
 460			"rpcbind\n", (port ? "" : "un"),
 461			prog, vers, prot, port);
 462
 463	msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
 464	if (port != 0) {
 465		msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];
 466		is_set = true;
 467	}
 468
 469	return rpcb_register_call(sn, sn->rpcb_local_clnt, &msg, is_set);
 470}
 471
 472/*
 473 * Fill in AF_INET family-specific arguments to register
 474 */
 475static int rpcb_register_inet4(struct sunrpc_net *sn,
 476			       const struct sockaddr *sap,
 477			       struct rpc_message *msg)
 478{
 479	const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
 480	struct rpcbind_args *map = msg->rpc_argp;
 481	unsigned short port = ntohs(sin->sin_port);
 482	bool is_set = false;
 483	int result;
 484
 485	map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 486
 487	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
 488		"local rpcbind\n", (port ? "" : "un"),
 489			map->r_prog, map->r_vers,
 490			map->r_addr, map->r_netid);
 491
 492	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 493	if (port != 0) {
 494		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 495		is_set = true;
 496	}
 497
 498	result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
 499	kfree(map->r_addr);
 500	return result;
 501}
 502
 503/*
 504 * Fill in AF_INET6 family-specific arguments to register
 505 */
 506static int rpcb_register_inet6(struct sunrpc_net *sn,
 507			       const struct sockaddr *sap,
 508			       struct rpc_message *msg)
 509{
 510	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
 511	struct rpcbind_args *map = msg->rpc_argp;
 512	unsigned short port = ntohs(sin6->sin6_port);
 513	bool is_set = false;
 514	int result;
 515
 516	map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 517
 518	dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
 519		"local rpcbind\n", (port ? "" : "un"),
 520			map->r_prog, map->r_vers,
 521			map->r_addr, map->r_netid);
 522
 523	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 524	if (port != 0) {
 525		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 526		is_set = true;
 527	}
 528
 529	result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
 530	kfree(map->r_addr);
 531	return result;
 532}
 533
 534static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn,
 535					     struct rpc_message *msg)
 536{
 537	struct rpcbind_args *map = msg->rpc_argp;
 538
 539	dprintk("RPC:       unregistering [%u, %u, '%s'] with "
 540		"local rpcbind\n",
 541			map->r_prog, map->r_vers, map->r_netid);
 542
 543	map->r_addr = "";
 544	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 545
 546	return rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, false);
 547}
 548
 549/**
 550 * rpcb_v4_register - set or unset a port registration with the local rpcbind
 551 * @net: target network namespace
 552 * @program: RPC program number of service to (un)register
 553 * @version: RPC version number of service to (un)register
 554 * @address: address family, IP address, and port to (un)register
 555 * @netid: netid of transport protocol to (un)register
 556 *
 557 * Returns zero if the registration request was dispatched successfully
 558 * and the rpcbind daemon returned success.  Otherwise, returns an errno
 559 * value that reflects the nature of the error (request could not be
 560 * dispatched, timed out, or rpcbind returned an error).
 561 *
 562 * RPC services invoke this function to advertise their contact
 563 * information via the system's rpcbind daemon.  RPC services
 564 * invoke this function once for each [program, version, address,
 565 * netid] tuple they wish to advertise.
 566 *
 567 * Callers may also unregister RPC services that are registered at a
 568 * specific address by setting the port number in @address to zero.
 569 * They may unregister all registered protocol families at once for
 570 * a service by passing a NULL @address argument.  If @netid is ""
 571 * then all netids for [program, version, address] are unregistered.
 572 *
 573 * This function uses rpcbind protocol version 4 to contact the
 574 * local rpcbind daemon.  The local rpcbind daemon must support
 575 * version 4 of the rpcbind protocol in order for these functions
 576 * to register a service successfully.
 577 *
 578 * Supported netids include "udp" and "tcp" for UDP and TCP over
 579 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
 580 * respectively.
 581 *
 582 * The contents of @address determine the address family and the
 583 * port to be registered.  The usual practice is to pass INADDR_ANY
 584 * as the raw address, but specifying a non-zero address is also
 585 * supported by this API if the caller wishes to advertise an RPC
 586 * service on a specific network interface.
 587 *
 588 * Note that passing in INADDR_ANY does not create the same service
 589 * registration as IN6ADDR_ANY.  The former advertises an RPC
 590 * service on any IPv4 address, but not on IPv6.  The latter
 591 * advertises the service on all IPv4 and IPv6 addresses.
 592 */
 593int rpcb_v4_register(struct net *net, const u32 program, const u32 version,
 594		     const struct sockaddr *address, const char *netid)
 595{
 596	struct rpcbind_args map = {
 597		.r_prog		= program,
 598		.r_vers		= version,
 599		.r_netid	= netid,
 600		.r_owner	= RPCB_OWNER_STRING,
 601	};
 602	struct rpc_message msg = {
 603		.rpc_argp	= &map,
 604	};
 605	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 606
 607	if (sn->rpcb_local_clnt4 == NULL)
 608		return -EPROTONOSUPPORT;
 609
 610	if (address == NULL)
 611		return rpcb_unregister_all_protofamilies(sn, &msg);
 612
 
 
 613	switch (address->sa_family) {
 614	case AF_INET:
 615		return rpcb_register_inet4(sn, address, &msg);
 616	case AF_INET6:
 617		return rpcb_register_inet6(sn, address, &msg);
 618	}
 619
 620	return -EAFNOSUPPORT;
 621}
 622
 623static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
 
 624{
 625	struct rpc_message msg = {
 626		.rpc_proc = proc,
 627		.rpc_argp = map,
 628		.rpc_resp = map,
 629	};
 630	struct rpc_task_setup task_setup_data = {
 631		.rpc_client = rpcb_clnt,
 632		.rpc_message = &msg,
 633		.callback_ops = &rpcb_getport_ops,
 634		.callback_data = map,
 635		.flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN,
 636	};
 637
 638	return rpc_run_task(&task_setup_data);
 639}
 640
 641/*
 642 * In the case where rpc clients have been cloned, we want to make
 643 * sure that we use the program number/version etc of the actual
 644 * owner of the xprt. To do so, we walk back up the tree of parents
 645 * to find whoever created the transport and/or whoever has the
 646 * autobind flag set.
 647 */
 648static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
 649{
 650	struct rpc_clnt *parent = clnt->cl_parent;
 651	struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch);
 652
 653	while (parent != clnt) {
 654		if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps)
 655			break;
 656		if (clnt->cl_autobind)
 657			break;
 658		clnt = parent;
 659		parent = parent->cl_parent;
 660	}
 661	return clnt;
 662}
 663
 664/**
 665 * rpcb_getport_async - obtain the port for a given RPC service on a given host
 666 * @task: task that is waiting for portmapper request
 667 *
 668 * This one can be called for an ongoing RPC request, and can be used in
 669 * an async (rpciod) context.
 670 */
 671void rpcb_getport_async(struct rpc_task *task)
 672{
 673	struct rpc_clnt *clnt;
 674	struct rpc_procinfo *proc;
 675	u32 bind_version;
 676	struct rpc_xprt *xprt;
 677	struct rpc_clnt	*rpcb_clnt;
 678	struct rpcbind_args *map;
 679	struct rpc_task	*child;
 680	struct sockaddr_storage addr;
 681	struct sockaddr *sap = (struct sockaddr *)&addr;
 682	size_t salen;
 683	int status;
 684
 685	rcu_read_lock();
 686	clnt = rpcb_find_transport_owner(task->tk_client);
 687	rcu_read_unlock();
 688	xprt = xprt_get(task->tk_xprt);
 689
 690	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
 691		task->tk_pid, __func__,
 692		xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot);
 693
 694	/* Put self on the wait queue to ensure we get notified if
 695	 * some other task is already attempting to bind the port */
 696	rpc_sleep_on(&xprt->binding, task, NULL);
 
 697
 698	if (xprt_test_and_set_binding(xprt)) {
 699		dprintk("RPC: %5u %s: waiting for another binder\n",
 700			task->tk_pid, __func__);
 701		xprt_put(xprt);
 702		return;
 703	}
 704
 705	/* Someone else may have bound if we slept */
 706	if (xprt_bound(xprt)) {
 707		status = 0;
 708		dprintk("RPC: %5u %s: already bound\n",
 709			task->tk_pid, __func__);
 710		goto bailout_nofree;
 711	}
 712
 713	/* Parent transport's destination address */
 714	salen = rpc_peeraddr(clnt, sap, sizeof(addr));
 715
 716	/* Don't ever use rpcbind v2 for AF_INET6 requests */
 717	switch (sap->sa_family) {
 718	case AF_INET:
 719		proc = rpcb_next_version[xprt->bind_index].rpc_proc;
 720		bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
 721		break;
 722	case AF_INET6:
 723		proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
 724		bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
 725		break;
 726	default:
 727		status = -EAFNOSUPPORT;
 728		dprintk("RPC: %5u %s: bad address family\n",
 729				task->tk_pid, __func__);
 730		goto bailout_nofree;
 731	}
 732	if (proc == NULL) {
 733		xprt->bind_index = 0;
 734		status = -EPFNOSUPPORT;
 735		dprintk("RPC: %5u %s: no more getport versions available\n",
 736			task->tk_pid, __func__);
 737		goto bailout_nofree;
 738	}
 739
 740	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
 741		task->tk_pid, __func__, bind_version);
 742
 743	rpcb_clnt = rpcb_create(xprt->xprt_net,
 744				clnt->cl_nodename,
 745				xprt->servername, sap, salen,
 746				xprt->prot, bind_version);
 
 
 747	if (IS_ERR(rpcb_clnt)) {
 748		status = PTR_ERR(rpcb_clnt);
 749		dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
 750			task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
 751		goto bailout_nofree;
 752	}
 753
 754	map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
 755	if (!map) {
 756		status = -ENOMEM;
 757		dprintk("RPC: %5u %s: no memory available\n",
 758			task->tk_pid, __func__);
 759		goto bailout_release_client;
 760	}
 761	map->r_prog = clnt->cl_prog;
 762	map->r_vers = clnt->cl_vers;
 763	map->r_prot = xprt->prot;
 764	map->r_port = 0;
 765	map->r_xprt = xprt;
 766	map->r_status = -EIO;
 767
 768	switch (bind_version) {
 769	case RPCBVERS_4:
 770	case RPCBVERS_3:
 771		map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID];
 772		map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC);
 
 
 
 
 773		map->r_owner = "";
 774		break;
 775	case RPCBVERS_2:
 776		map->r_addr = NULL;
 777		break;
 778	default:
 779		BUG();
 780	}
 781
 782	child = rpcb_call_async(rpcb_clnt, map, proc);
 783	rpc_release_client(rpcb_clnt);
 784	if (IS_ERR(child)) {
 785		/* rpcb_map_release() has freed the arguments */
 786		dprintk("RPC: %5u %s: rpc_run_task failed\n",
 787			task->tk_pid, __func__);
 788		return;
 789	}
 790
 791	xprt->stat.bind_count++;
 792	rpc_put_task(child);
 793	return;
 794
 
 
 795bailout_release_client:
 796	rpc_release_client(rpcb_clnt);
 797bailout_nofree:
 798	rpcb_wake_rpcbind_waiters(xprt, status);
 799	task->tk_status = status;
 800	xprt_put(xprt);
 801}
 802EXPORT_SYMBOL_GPL(rpcb_getport_async);
 803
 804/*
 805 * Rpcbind child task calls this callback via tk_exit.
 806 */
 807static void rpcb_getport_done(struct rpc_task *child, void *data)
 808{
 809	struct rpcbind_args *map = data;
 810	struct rpc_xprt *xprt = map->r_xprt;
 811	int status = child->tk_status;
 
 812
 813	/* Garbage reply: retry with a lesser rpcbind version */
 814	if (status == -EIO)
 815		status = -EPROTONOSUPPORT;
 816
 817	/* rpcbind server doesn't support this rpcbind protocol version */
 818	if (status == -EPROTONOSUPPORT)
 819		xprt->bind_index++;
 820
 821	if (status < 0) {
 822		/* rpcbind server not available on remote host? */
 823		xprt->ops->set_port(xprt, 0);
 
 824	} else if (map->r_port == 0) {
 825		/* Requested RPC service wasn't registered on remote host */
 826		xprt->ops->set_port(xprt, 0);
 827		status = -EACCES;
 828	} else {
 829		/* Succeeded */
 830		xprt->ops->set_port(xprt, map->r_port);
 831		xprt_set_bound(xprt);
 832		status = 0;
 833	}
 834
 835	dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
 836			child->tk_pid, status, map->r_port);
 837
 838	map->r_status = status;
 839}
 840
 841/*
 842 * XDR functions for rpcbind
 843 */
 844
 845static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr,
 846			     const struct rpcbind_args *rpcb)
 847{
 
 848	__be32 *p;
 849
 850	dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n",
 851			req->rq_task->tk_pid,
 852			req->rq_task->tk_msg.rpc_proc->p_name,
 853			rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
 854
 855	p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2);
 856	*p++ = cpu_to_be32(rpcb->r_prog);
 857	*p++ = cpu_to_be32(rpcb->r_vers);
 858	*p++ = cpu_to_be32(rpcb->r_prot);
 859	*p   = cpu_to_be32(rpcb->r_port);
 860}
 861
 862static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr,
 863			    struct rpcbind_args *rpcb)
 864{
 
 865	unsigned long port;
 866	__be32 *p;
 867
 868	rpcb->r_port = 0;
 869
 870	p = xdr_inline_decode(xdr, 4);
 871	if (unlikely(p == NULL))
 872		return -EIO;
 873
 874	port = be32_to_cpup(p);
 875	dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid,
 876			req->rq_task->tk_msg.rpc_proc->p_name, port);
 877	if (unlikely(port > USHRT_MAX))
 878		return -EIO;
 879
 880	rpcb->r_port = port;
 881	return 0;
 882}
 883
 884static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr,
 885			unsigned int *boolp)
 886{
 
 887	__be32 *p;
 888
 889	p = xdr_inline_decode(xdr, 4);
 890	if (unlikely(p == NULL))
 891		return -EIO;
 892
 893	*boolp = 0;
 894	if (*p != xdr_zero)
 895		*boolp = 1;
 896
 897	dprintk("RPC: %5u RPCB_%s call %s\n",
 898			req->rq_task->tk_pid,
 899			req->rq_task->tk_msg.rpc_proc->p_name,
 900			(*boolp ? "succeeded" : "failed"));
 901	return 0;
 902}
 903
 904static void encode_rpcb_string(struct xdr_stream *xdr, const char *string,
 905			       const u32 maxstrlen)
 906{
 907	__be32 *p;
 908	u32 len;
 909
 910	len = strlen(string);
 911	WARN_ON_ONCE(len > maxstrlen);
 912	if (len > maxstrlen)
 913		/* truncate and hope for the best */
 914		len = maxstrlen;
 915	p = xdr_reserve_space(xdr, 4 + len);
 916	xdr_encode_opaque(p, string, len);
 917}
 918
 919static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 920			     const struct rpcbind_args *rpcb)
 921{
 
 922	__be32 *p;
 923
 924	dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n",
 925			req->rq_task->tk_pid,
 926			req->rq_task->tk_msg.rpc_proc->p_name,
 927			rpcb->r_prog, rpcb->r_vers,
 928			rpcb->r_netid, rpcb->r_addr);
 929
 930	p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2);
 931	*p++ = cpu_to_be32(rpcb->r_prog);
 932	*p = cpu_to_be32(rpcb->r_vers);
 933
 934	encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN);
 935	encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN);
 936	encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN);
 937}
 938
 939static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 940			    struct rpcbind_args *rpcb)
 941{
 
 942	struct sockaddr_storage address;
 943	struct sockaddr *sap = (struct sockaddr *)&address;
 944	__be32 *p;
 945	u32 len;
 946
 947	rpcb->r_port = 0;
 948
 949	p = xdr_inline_decode(xdr, 4);
 950	if (unlikely(p == NULL))
 951		goto out_fail;
 952	len = be32_to_cpup(p);
 953
 954	/*
 955	 * If the returned universal address is a null string,
 956	 * the requested RPC service was not registered.
 957	 */
 958	if (len == 0) {
 959		dprintk("RPC: %5u RPCB reply: program not registered\n",
 960				req->rq_task->tk_pid);
 961		return 0;
 962	}
 963
 964	if (unlikely(len > RPCBIND_MAXUADDRLEN))
 965		goto out_fail;
 966
 967	p = xdr_inline_decode(xdr, len);
 968	if (unlikely(p == NULL))
 969		goto out_fail;
 970	dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid,
 971			req->rq_task->tk_msg.rpc_proc->p_name, (char *)p);
 972
 973	if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len,
 974				sap, sizeof(address)) == 0)
 975		goto out_fail;
 976	rpcb->r_port = rpc_get_port(sap);
 977
 978	return 0;
 979
 980out_fail:
 981	dprintk("RPC: %5u malformed RPCB_%s reply\n",
 982			req->rq_task->tk_pid,
 983			req->rq_task->tk_msg.rpc_proc->p_name);
 984	return -EIO;
 985}
 986
 987/*
 988 * Not all rpcbind procedures described in RFC 1833 are implemented
 989 * since the Linux kernel RPC code requires only these.
 990 */
 991
 992static struct rpc_procinfo rpcb_procedures2[] = {
 993	[RPCBPROC_SET] = {
 994		.p_proc		= RPCBPROC_SET,
 995		.p_encode	= (kxdreproc_t)rpcb_enc_mapping,
 996		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
 997		.p_arglen	= RPCB_mappingargs_sz,
 998		.p_replen	= RPCB_setres_sz,
 999		.p_statidx	= RPCBPROC_SET,
1000		.p_timer	= 0,
1001		.p_name		= "SET",
1002	},
1003	[RPCBPROC_UNSET] = {
1004		.p_proc		= RPCBPROC_UNSET,
1005		.p_encode	= (kxdreproc_t)rpcb_enc_mapping,
1006		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
1007		.p_arglen	= RPCB_mappingargs_sz,
1008		.p_replen	= RPCB_setres_sz,
1009		.p_statidx	= RPCBPROC_UNSET,
1010		.p_timer	= 0,
1011		.p_name		= "UNSET",
1012	},
1013	[RPCBPROC_GETPORT] = {
1014		.p_proc		= RPCBPROC_GETPORT,
1015		.p_encode	= (kxdreproc_t)rpcb_enc_mapping,
1016		.p_decode	= (kxdrdproc_t)rpcb_dec_getport,
1017		.p_arglen	= RPCB_mappingargs_sz,
1018		.p_replen	= RPCB_getportres_sz,
1019		.p_statidx	= RPCBPROC_GETPORT,
1020		.p_timer	= 0,
1021		.p_name		= "GETPORT",
1022	},
1023};
1024
1025static struct rpc_procinfo rpcb_procedures3[] = {
1026	[RPCBPROC_SET] = {
1027		.p_proc		= RPCBPROC_SET,
1028		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1029		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
1030		.p_arglen	= RPCB_getaddrargs_sz,
1031		.p_replen	= RPCB_setres_sz,
1032		.p_statidx	= RPCBPROC_SET,
1033		.p_timer	= 0,
1034		.p_name		= "SET",
1035	},
1036	[RPCBPROC_UNSET] = {
1037		.p_proc		= RPCBPROC_UNSET,
1038		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1039		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
1040		.p_arglen	= RPCB_getaddrargs_sz,
1041		.p_replen	= RPCB_setres_sz,
1042		.p_statidx	= RPCBPROC_UNSET,
1043		.p_timer	= 0,
1044		.p_name		= "UNSET",
1045	},
1046	[RPCBPROC_GETADDR] = {
1047		.p_proc		= RPCBPROC_GETADDR,
1048		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1049		.p_decode	= (kxdrdproc_t)rpcb_dec_getaddr,
1050		.p_arglen	= RPCB_getaddrargs_sz,
1051		.p_replen	= RPCB_getaddrres_sz,
1052		.p_statidx	= RPCBPROC_GETADDR,
1053		.p_timer	= 0,
1054		.p_name		= "GETADDR",
1055	},
1056};
1057
1058static struct rpc_procinfo rpcb_procedures4[] = {
1059	[RPCBPROC_SET] = {
1060		.p_proc		= RPCBPROC_SET,
1061		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1062		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
1063		.p_arglen	= RPCB_getaddrargs_sz,
1064		.p_replen	= RPCB_setres_sz,
1065		.p_statidx	= RPCBPROC_SET,
1066		.p_timer	= 0,
1067		.p_name		= "SET",
1068	},
1069	[RPCBPROC_UNSET] = {
1070		.p_proc		= RPCBPROC_UNSET,
1071		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1072		.p_decode	= (kxdrdproc_t)rpcb_dec_set,
1073		.p_arglen	= RPCB_getaddrargs_sz,
1074		.p_replen	= RPCB_setres_sz,
1075		.p_statidx	= RPCBPROC_UNSET,
1076		.p_timer	= 0,
1077		.p_name		= "UNSET",
1078	},
1079	[RPCBPROC_GETADDR] = {
1080		.p_proc		= RPCBPROC_GETADDR,
1081		.p_encode	= (kxdreproc_t)rpcb_enc_getaddr,
1082		.p_decode	= (kxdrdproc_t)rpcb_dec_getaddr,
1083		.p_arglen	= RPCB_getaddrargs_sz,
1084		.p_replen	= RPCB_getaddrres_sz,
1085		.p_statidx	= RPCBPROC_GETADDR,
1086		.p_timer	= 0,
1087		.p_name		= "GETADDR",
1088	},
1089};
1090
1091static const struct rpcb_info rpcb_next_version[] = {
1092	{
1093		.rpc_vers	= RPCBVERS_2,
1094		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
1095	},
1096	{
1097		.rpc_proc	= NULL,
1098	},
1099};
1100
1101static const struct rpcb_info rpcb_next_version6[] = {
1102	{
1103		.rpc_vers	= RPCBVERS_4,
1104		.rpc_proc	= &rpcb_procedures4[RPCBPROC_GETADDR],
1105	},
1106	{
1107		.rpc_vers	= RPCBVERS_3,
1108		.rpc_proc	= &rpcb_procedures3[RPCBPROC_GETADDR],
1109	},
1110	{
1111		.rpc_proc	= NULL,
1112	},
1113};
1114
 
1115static const struct rpc_version rpcb_version2 = {
1116	.number		= RPCBVERS_2,
1117	.nrprocs	= ARRAY_SIZE(rpcb_procedures2),
1118	.procs		= rpcb_procedures2
 
1119};
1120
 
1121static const struct rpc_version rpcb_version3 = {
1122	.number		= RPCBVERS_3,
1123	.nrprocs	= ARRAY_SIZE(rpcb_procedures3),
1124	.procs		= rpcb_procedures3
 
1125};
1126
 
1127static const struct rpc_version rpcb_version4 = {
1128	.number		= RPCBVERS_4,
1129	.nrprocs	= ARRAY_SIZE(rpcb_procedures4),
1130	.procs		= rpcb_procedures4
 
1131};
1132
1133static const struct rpc_version *rpcb_version[] = {
1134	NULL,
1135	NULL,
1136	&rpcb_version2,
1137	&rpcb_version3,
1138	&rpcb_version4
1139};
1140
1141static struct rpc_stat rpcb_stats;
1142
1143static const struct rpc_program rpcb_program = {
1144	.name		= "rpcbind",
1145	.number		= RPCBIND_PROGRAM,
1146	.nrvers		= ARRAY_SIZE(rpcb_version),
1147	.version	= rpcb_version,
1148	.stats		= &rpcb_stats,
1149};
v6.2
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
   4 * protocol
   5 *
   6 * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
   7 * RFC 3530: "Network File System (NFS) version 4 Protocol"
   8 *
   9 * Original: Gilles Quillard, Bull Open Source, 2005 <gilles.quillard@bull.net>
  10 * Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
  11 *
  12 * Descended from net/sunrpc/pmap_clnt.c,
  13 *  Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
  14 */
  15
  16#include <linux/module.h>
  17
  18#include <linux/types.h>
  19#include <linux/socket.h>
  20#include <linux/un.h>
  21#include <linux/in.h>
  22#include <linux/in6.h>
  23#include <linux/kernel.h>
  24#include <linux/errno.h>
  25#include <linux/mutex.h>
  26#include <linux/slab.h>
  27#include <net/ipv6.h>
  28
  29#include <linux/sunrpc/clnt.h>
  30#include <linux/sunrpc/addr.h>
  31#include <linux/sunrpc/sched.h>
  32#include <linux/sunrpc/xprtsock.h>
  33
  34#include <trace/events/sunrpc.h>
  35
  36#include "netns.h"
 
 
  37
  38#define RPCBIND_SOCK_PATHNAME	"/var/run/rpcbind.sock"
  39
  40#define RPCBIND_PROGRAM		(100000u)
  41#define RPCBIND_PORT		(111u)
  42
  43#define RPCBVERS_2		(2u)
  44#define RPCBVERS_3		(3u)
  45#define RPCBVERS_4		(4u)
  46
  47enum {
  48	RPCBPROC_NULL,
  49	RPCBPROC_SET,
  50	RPCBPROC_UNSET,
  51	RPCBPROC_GETPORT,
  52	RPCBPROC_GETADDR = 3,		/* alias for GETPORT */
  53	RPCBPROC_DUMP,
  54	RPCBPROC_CALLIT,
  55	RPCBPROC_BCAST = 5,		/* alias for CALLIT */
  56	RPCBPROC_GETTIME,
  57	RPCBPROC_UADDR2TADDR,
  58	RPCBPROC_TADDR2UADDR,
  59	RPCBPROC_GETVERSADDR,
  60	RPCBPROC_INDIRECT,
  61	RPCBPROC_GETADDRLIST,
  62	RPCBPROC_GETSTAT,
  63};
  64
  65/*
  66 * r_owner
  67 *
  68 * The "owner" is allowed to unset a service in the rpcbind database.
  69 *
  70 * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a
  71 * UID which it maps to a local user name via a password lookup.
  72 * In all other cases it is ignored.
  73 *
  74 * For SET/UNSET requests, user space provides a value, even for
  75 * network requests, and GETADDR uses an empty string.  We follow
  76 * those precedents here.
  77 */
  78#define RPCB_OWNER_STRING	"0"
  79#define RPCB_MAXOWNERLEN	sizeof(RPCB_OWNER_STRING)
  80
  81/*
  82 * XDR data type sizes
  83 */
  84#define RPCB_program_sz		(1)
  85#define RPCB_version_sz		(1)
  86#define RPCB_protocol_sz	(1)
  87#define RPCB_port_sz		(1)
  88#define RPCB_boolean_sz		(1)
  89
  90#define RPCB_netid_sz		(1 + XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
  91#define RPCB_addr_sz		(1 + XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
  92#define RPCB_ownerstring_sz	(1 + XDR_QUADLEN(RPCB_MAXOWNERLEN))
  93
  94/*
  95 * XDR argument and result sizes
  96 */
  97#define RPCB_mappingargs_sz	(RPCB_program_sz + RPCB_version_sz + \
  98				RPCB_protocol_sz + RPCB_port_sz)
  99#define RPCB_getaddrargs_sz	(RPCB_program_sz + RPCB_version_sz + \
 100				RPCB_netid_sz + RPCB_addr_sz + \
 101				RPCB_ownerstring_sz)
 102
 103#define RPCB_getportres_sz	RPCB_port_sz
 104#define RPCB_setres_sz		RPCB_boolean_sz
 105
 106/*
 107 * Note that RFC 1833 does not put any size restrictions on the
 108 * address string returned by the remote rpcbind database.
 109 */
 110#define RPCB_getaddrres_sz	RPCB_addr_sz
 111
 112static void			rpcb_getport_done(struct rpc_task *, void *);
 113static void			rpcb_map_release(void *data);
 114static const struct rpc_program	rpcb_program;
 115
 116struct rpcbind_args {
 117	struct rpc_xprt *	r_xprt;
 118
 119	u32			r_prog;
 120	u32			r_vers;
 121	u32			r_prot;
 122	unsigned short		r_port;
 123	const char *		r_netid;
 124	const char *		r_addr;
 125	const char *		r_owner;
 126
 127	int			r_status;
 128};
 129
 130static const struct rpc_procinfo rpcb_procedures2[];
 131static const struct rpc_procinfo rpcb_procedures3[];
 132static const struct rpc_procinfo rpcb_procedures4[];
 133
 134struct rpcb_info {
 135	u32			rpc_vers;
 136	const struct rpc_procinfo *rpc_proc;
 137};
 138
 139static const struct rpcb_info rpcb_next_version[];
 140static const struct rpcb_info rpcb_next_version6[];
 141
 142static const struct rpc_call_ops rpcb_getport_ops = {
 143	.rpc_call_done		= rpcb_getport_done,
 144	.rpc_release		= rpcb_map_release,
 145};
 146
 147static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
 148{
 149	xprt_clear_binding(xprt);
 150	rpc_wake_up_status(&xprt->binding, status);
 151}
 152
 153static void rpcb_map_release(void *data)
 154{
 155	struct rpcbind_args *map = data;
 156
 157	rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
 158	xprt_put(map->r_xprt);
 159	kfree(map->r_addr);
 160	kfree(map);
 161}
 162
 163static int rpcb_get_local(struct net *net)
 164{
 165	int cnt;
 166	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 167
 168	spin_lock(&sn->rpcb_clnt_lock);
 169	if (sn->rpcb_users)
 170		sn->rpcb_users++;
 171	cnt = sn->rpcb_users;
 172	spin_unlock(&sn->rpcb_clnt_lock);
 173
 174	return cnt;
 175}
 176
 177void rpcb_put_local(struct net *net)
 178{
 179	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 180	struct rpc_clnt *clnt = sn->rpcb_local_clnt;
 181	struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4;
 182	int shutdown = 0;
 183
 184	spin_lock(&sn->rpcb_clnt_lock);
 185	if (sn->rpcb_users) {
 186		if (--sn->rpcb_users == 0) {
 187			sn->rpcb_local_clnt = NULL;
 188			sn->rpcb_local_clnt4 = NULL;
 189		}
 190		shutdown = !sn->rpcb_users;
 191	}
 192	spin_unlock(&sn->rpcb_clnt_lock);
 193
 194	if (shutdown) {
 195		/*
 196		 * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
 197		 */
 198		if (clnt4)
 199			rpc_shutdown_client(clnt4);
 200		if (clnt)
 201			rpc_shutdown_client(clnt);
 202	}
 203}
 204
 205static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt,
 206			struct rpc_clnt *clnt4,
 207			bool is_af_local)
 208{
 209	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 210
 211	/* Protected by rpcb_create_local_mutex */
 212	sn->rpcb_local_clnt = clnt;
 213	sn->rpcb_local_clnt4 = clnt4;
 214	sn->rpcb_is_af_local = is_af_local ? 1 : 0;
 215	smp_wmb();
 216	sn->rpcb_users = 1;
 
 
 
 
 217}
 218
 219/*
 220 * Returns zero on success, otherwise a negative errno value
 221 * is returned.
 222 */
 223static int rpcb_create_local_unix(struct net *net)
 224{
 225	static const struct sockaddr_un rpcb_localaddr_rpcbind = {
 226		.sun_family		= AF_LOCAL,
 227		.sun_path		= RPCBIND_SOCK_PATHNAME,
 228	};
 229	struct rpc_create_args args = {
 230		.net		= net,
 231		.protocol	= XPRT_TRANSPORT_LOCAL,
 232		.address	= (struct sockaddr *)&rpcb_localaddr_rpcbind,
 233		.addrsize	= sizeof(rpcb_localaddr_rpcbind),
 234		.servername	= "localhost",
 235		.program	= &rpcb_program,
 236		.version	= RPCBVERS_2,
 237		.authflavor	= RPC_AUTH_NULL,
 238		.cred		= current_cred(),
 239		/*
 240		 * We turn off the idle timeout to prevent the kernel
 241		 * from automatically disconnecting the socket.
 242		 * Otherwise, we'd have to cache the mount namespace
 243		 * of the caller and somehow pass that to the socket
 244		 * reconnect code.
 245		 */
 246		.flags		= RPC_CLNT_CREATE_NO_IDLE_TIMEOUT,
 247	};
 248	struct rpc_clnt *clnt, *clnt4;
 249	int result = 0;
 250
 251	/*
 252	 * Because we requested an RPC PING at transport creation time,
 253	 * this works only if the user space portmapper is rpcbind, and
 254	 * it's listening on AF_LOCAL on the named socket.
 255	 */
 256	clnt = rpc_create(&args);
 257	if (IS_ERR(clnt)) {
 
 
 258		result = PTR_ERR(clnt);
 259		goto out;
 260	}
 261
 262	clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 263	if (IS_ERR(clnt4))
 
 
 
 264		clnt4 = NULL;
 
 265
 266	rpcb_set_local(net, clnt, clnt4, true);
 267
 268out:
 269	return result;
 270}
 271
 272/*
 273 * Returns zero on success, otherwise a negative errno value
 274 * is returned.
 275 */
 276static int rpcb_create_local_net(struct net *net)
 277{
 278	static const struct sockaddr_in rpcb_inaddr_loopback = {
 279		.sin_family		= AF_INET,
 280		.sin_addr.s_addr	= htonl(INADDR_LOOPBACK),
 281		.sin_port		= htons(RPCBIND_PORT),
 282	};
 283	struct rpc_create_args args = {
 284		.net		= net,
 285		.protocol	= XPRT_TRANSPORT_TCP,
 286		.address	= (struct sockaddr *)&rpcb_inaddr_loopback,
 287		.addrsize	= sizeof(rpcb_inaddr_loopback),
 288		.servername	= "localhost",
 289		.program	= &rpcb_program,
 290		.version	= RPCBVERS_2,
 291		.authflavor	= RPC_AUTH_UNIX,
 292		.cred		= current_cred(),
 293		.flags		= RPC_CLNT_CREATE_NOPING,
 294	};
 295	struct rpc_clnt *clnt, *clnt4;
 296	int result = 0;
 297
 298	clnt = rpc_create(&args);
 299	if (IS_ERR(clnt)) {
 
 
 300		result = PTR_ERR(clnt);
 301		goto out;
 302	}
 303
 304	/*
 305	 * This results in an RPC ping.  On systems running portmapper,
 306	 * the v4 ping will fail.  Proceed anyway, but disallow rpcb
 307	 * v4 upcalls.
 308	 */
 309	clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 310	if (IS_ERR(clnt4))
 
 
 
 311		clnt4 = NULL;
 
 312
 313	rpcb_set_local(net, clnt, clnt4, false);
 314
 315out:
 316	return result;
 317}
 318
 319/*
 320 * Returns zero on success, otherwise a negative errno value
 321 * is returned.
 322 */
 323int rpcb_create_local(struct net *net)
 324{
 325	static DEFINE_MUTEX(rpcb_create_local_mutex);
 326	int result = 0;
 327
 328	if (rpcb_get_local(net))
 329		return result;
 330
 331	mutex_lock(&rpcb_create_local_mutex);
 332	if (rpcb_get_local(net))
 333		goto out;
 334
 335	if (rpcb_create_local_unix(net) != 0)
 336		result = rpcb_create_local_net(net);
 337
 338out:
 339	mutex_unlock(&rpcb_create_local_mutex);
 340	return result;
 341}
 342
 343static struct rpc_clnt *rpcb_create(struct net *net, const char *nodename,
 344				    const char *hostname,
 345				    struct sockaddr *srvaddr, size_t salen,
 346				    int proto, u32 version,
 347				    const struct cred *cred,
 348				    const struct rpc_timeout *timeo)
 349{
 350	struct rpc_create_args args = {
 351		.net		= net,
 352		.protocol	= proto,
 353		.address	= srvaddr,
 354		.addrsize	= salen,
 355		.timeout	= timeo,
 356		.servername	= hostname,
 357		.nodename	= nodename,
 358		.program	= &rpcb_program,
 359		.version	= version,
 360		.authflavor	= RPC_AUTH_UNIX,
 361		.cred		= cred,
 362		.flags		= (RPC_CLNT_CREATE_NOPING |
 363					RPC_CLNT_CREATE_NONPRIVPORT),
 364	};
 365
 366	switch (srvaddr->sa_family) {
 367	case AF_INET:
 368		((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
 369		break;
 370	case AF_INET6:
 371		((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
 372		break;
 373	default:
 374		return ERR_PTR(-EAFNOSUPPORT);
 375	}
 376
 377	return rpc_create(&args);
 378}
 379
 380static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set)
 381{
 382	int flags = RPC_TASK_NOCONNECT;
 383	int error, result = 0;
 384
 385	if (is_set || !sn->rpcb_is_af_local)
 386		flags = RPC_TASK_SOFTCONN;
 387	msg->rpc_resp = &result;
 388
 389	error = rpc_call_sync(clnt, msg, flags);
 390	if (error < 0)
 
 
 391		return error;
 
 392
 393	if (!result)
 394		return -EACCES;
 395	return 0;
 396}
 397
 398/**
 399 * rpcb_register - set or unset a port registration with the local rpcbind svc
 400 * @net: target network namespace
 401 * @prog: RPC program number to bind
 402 * @vers: RPC version number to bind
 403 * @prot: transport protocol to register
 404 * @port: port value to register
 405 *
 406 * Returns zero if the registration request was dispatched successfully
 407 * and the rpcbind daemon returned success.  Otherwise, returns an errno
 408 * value that reflects the nature of the error (request could not be
 409 * dispatched, timed out, or rpcbind returned an error).
 410 *
 411 * RPC services invoke this function to advertise their contact
 412 * information via the system's rpcbind daemon.  RPC services
 413 * invoke this function once for each [program, version, transport]
 414 * tuple they wish to advertise.
 415 *
 416 * Callers may also unregister RPC services that are no longer
 417 * available by setting the passed-in port to zero.  This removes
 418 * all registered transports for [program, version] from the local
 419 * rpcbind database.
 420 *
 421 * This function uses rpcbind protocol version 2 to contact the
 422 * local rpcbind daemon.
 423 *
 424 * Registration works over both AF_INET and AF_INET6, and services
 425 * registered via this function are advertised as available for any
 426 * address.  If the local rpcbind daemon is listening on AF_INET6,
 427 * services registered via this function will be advertised on
 428 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
 429 * addresses).
 430 */
 431int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port)
 432{
 433	struct rpcbind_args map = {
 434		.r_prog		= prog,
 435		.r_vers		= vers,
 436		.r_prot		= prot,
 437		.r_port		= port,
 438	};
 439	struct rpc_message msg = {
 440		.rpc_argp	= &map,
 441	};
 442	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 443	bool is_set = false;
 444
 445	trace_pmap_register(prog, vers, prot, port);
 
 
 446
 447	msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
 448	if (port != 0) {
 449		msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];
 450		is_set = true;
 451	}
 452
 453	return rpcb_register_call(sn, sn->rpcb_local_clnt, &msg, is_set);
 454}
 455
 456/*
 457 * Fill in AF_INET family-specific arguments to register
 458 */
 459static int rpcb_register_inet4(struct sunrpc_net *sn,
 460			       const struct sockaddr *sap,
 461			       struct rpc_message *msg)
 462{
 463	const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
 464	struct rpcbind_args *map = msg->rpc_argp;
 465	unsigned short port = ntohs(sin->sin_port);
 466	bool is_set = false;
 467	int result;
 468
 469	map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 470
 
 
 
 
 
 471	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 472	if (port != 0) {
 473		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 474		is_set = true;
 475	}
 476
 477	result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
 478	kfree(map->r_addr);
 479	return result;
 480}
 481
 482/*
 483 * Fill in AF_INET6 family-specific arguments to register
 484 */
 485static int rpcb_register_inet6(struct sunrpc_net *sn,
 486			       const struct sockaddr *sap,
 487			       struct rpc_message *msg)
 488{
 489	const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
 490	struct rpcbind_args *map = msg->rpc_argp;
 491	unsigned short port = ntohs(sin6->sin6_port);
 492	bool is_set = false;
 493	int result;
 494
 495	map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 496
 
 
 
 
 
 497	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 498	if (port != 0) {
 499		msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 500		is_set = true;
 501	}
 502
 503	result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
 504	kfree(map->r_addr);
 505	return result;
 506}
 507
 508static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn,
 509					     struct rpc_message *msg)
 510{
 511	struct rpcbind_args *map = msg->rpc_argp;
 512
 513	trace_rpcb_unregister(map->r_prog, map->r_vers, map->r_netid);
 
 
 514
 515	map->r_addr = "";
 516	msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 517
 518	return rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, false);
 519}
 520
 521/**
 522 * rpcb_v4_register - set or unset a port registration with the local rpcbind
 523 * @net: target network namespace
 524 * @program: RPC program number of service to (un)register
 525 * @version: RPC version number of service to (un)register
 526 * @address: address family, IP address, and port to (un)register
 527 * @netid: netid of transport protocol to (un)register
 528 *
 529 * Returns zero if the registration request was dispatched successfully
 530 * and the rpcbind daemon returned success.  Otherwise, returns an errno
 531 * value that reflects the nature of the error (request could not be
 532 * dispatched, timed out, or rpcbind returned an error).
 533 *
 534 * RPC services invoke this function to advertise their contact
 535 * information via the system's rpcbind daemon.  RPC services
 536 * invoke this function once for each [program, version, address,
 537 * netid] tuple they wish to advertise.
 538 *
 539 * Callers may also unregister RPC services that are registered at a
 540 * specific address by setting the port number in @address to zero.
 541 * They may unregister all registered protocol families at once for
 542 * a service by passing a NULL @address argument.  If @netid is ""
 543 * then all netids for [program, version, address] are unregistered.
 544 *
 545 * This function uses rpcbind protocol version 4 to contact the
 546 * local rpcbind daemon.  The local rpcbind daemon must support
 547 * version 4 of the rpcbind protocol in order for these functions
 548 * to register a service successfully.
 549 *
 550 * Supported netids include "udp" and "tcp" for UDP and TCP over
 551 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
 552 * respectively.
 553 *
 554 * The contents of @address determine the address family and the
 555 * port to be registered.  The usual practice is to pass INADDR_ANY
 556 * as the raw address, but specifying a non-zero address is also
 557 * supported by this API if the caller wishes to advertise an RPC
 558 * service on a specific network interface.
 559 *
 560 * Note that passing in INADDR_ANY does not create the same service
 561 * registration as IN6ADDR_ANY.  The former advertises an RPC
 562 * service on any IPv4 address, but not on IPv6.  The latter
 563 * advertises the service on all IPv4 and IPv6 addresses.
 564 */
 565int rpcb_v4_register(struct net *net, const u32 program, const u32 version,
 566		     const struct sockaddr *address, const char *netid)
 567{
 568	struct rpcbind_args map = {
 569		.r_prog		= program,
 570		.r_vers		= version,
 571		.r_netid	= netid,
 572		.r_owner	= RPCB_OWNER_STRING,
 573	};
 574	struct rpc_message msg = {
 575		.rpc_argp	= &map,
 576	};
 577	struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 578
 579	if (sn->rpcb_local_clnt4 == NULL)
 580		return -EPROTONOSUPPORT;
 581
 582	if (address == NULL)
 583		return rpcb_unregister_all_protofamilies(sn, &msg);
 584
 585	trace_rpcb_register(map.r_prog, map.r_vers, map.r_addr, map.r_netid);
 586
 587	switch (address->sa_family) {
 588	case AF_INET:
 589		return rpcb_register_inet4(sn, address, &msg);
 590	case AF_INET6:
 591		return rpcb_register_inet6(sn, address, &msg);
 592	}
 593
 594	return -EAFNOSUPPORT;
 595}
 596
 597static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt,
 598		struct rpcbind_args *map, const struct rpc_procinfo *proc)
 599{
 600	struct rpc_message msg = {
 601		.rpc_proc = proc,
 602		.rpc_argp = map,
 603		.rpc_resp = map,
 604	};
 605	struct rpc_task_setup task_setup_data = {
 606		.rpc_client = rpcb_clnt,
 607		.rpc_message = &msg,
 608		.callback_ops = &rpcb_getport_ops,
 609		.callback_data = map,
 610		.flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN,
 611	};
 612
 613	return rpc_run_task(&task_setup_data);
 614}
 615
 616/*
 617 * In the case where rpc clients have been cloned, we want to make
 618 * sure that we use the program number/version etc of the actual
 619 * owner of the xprt. To do so, we walk back up the tree of parents
 620 * to find whoever created the transport and/or whoever has the
 621 * autobind flag set.
 622 */
 623static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
 624{
 625	struct rpc_clnt *parent = clnt->cl_parent;
 626	struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch);
 627
 628	while (parent != clnt) {
 629		if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps)
 630			break;
 631		if (clnt->cl_autobind)
 632			break;
 633		clnt = parent;
 634		parent = parent->cl_parent;
 635	}
 636	return clnt;
 637}
 638
 639/**
 640 * rpcb_getport_async - obtain the port for a given RPC service on a given host
 641 * @task: task that is waiting for portmapper request
 642 *
 643 * This one can be called for an ongoing RPC request, and can be used in
 644 * an async (rpciod) context.
 645 */
 646void rpcb_getport_async(struct rpc_task *task)
 647{
 648	struct rpc_clnt *clnt;
 649	const struct rpc_procinfo *proc;
 650	u32 bind_version;
 651	struct rpc_xprt *xprt;
 652	struct rpc_clnt	*rpcb_clnt;
 653	struct rpcbind_args *map;
 654	struct rpc_task	*child;
 655	struct sockaddr_storage addr;
 656	struct sockaddr *sap = (struct sockaddr *)&addr;
 657	size_t salen;
 658	int status;
 659
 660	rcu_read_lock();
 661	clnt = rpcb_find_transport_owner(task->tk_client);
 662	rcu_read_unlock();
 663	xprt = xprt_get(task->tk_xprt);
 664
 
 
 
 
 665	/* Put self on the wait queue to ensure we get notified if
 666	 * some other task is already attempting to bind the port */
 667	rpc_sleep_on_timeout(&xprt->binding, task,
 668			NULL, jiffies + xprt->bind_timeout);
 669
 670	if (xprt_test_and_set_binding(xprt)) {
 
 
 671		xprt_put(xprt);
 672		return;
 673	}
 674
 675	/* Someone else may have bound if we slept */
 676	if (xprt_bound(xprt)) {
 677		status = 0;
 
 
 678		goto bailout_nofree;
 679	}
 680
 681	/* Parent transport's destination address */
 682	salen = rpc_peeraddr(clnt, sap, sizeof(addr));
 683
 684	/* Don't ever use rpcbind v2 for AF_INET6 requests */
 685	switch (sap->sa_family) {
 686	case AF_INET:
 687		proc = rpcb_next_version[xprt->bind_index].rpc_proc;
 688		bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
 689		break;
 690	case AF_INET6:
 691		proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
 692		bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
 693		break;
 694	default:
 695		status = -EAFNOSUPPORT;
 
 
 696		goto bailout_nofree;
 697	}
 698	if (proc == NULL) {
 699		xprt->bind_index = 0;
 700		status = -EPFNOSUPPORT;
 
 
 701		goto bailout_nofree;
 702	}
 703
 704	trace_rpcb_getport(clnt, task, bind_version);
 
 705
 706	rpcb_clnt = rpcb_create(xprt->xprt_net,
 707				clnt->cl_nodename,
 708				xprt->servername, sap, salen,
 709				xprt->prot, bind_version,
 710				clnt->cl_cred,
 711				task->tk_client->cl_timeout);
 712	if (IS_ERR(rpcb_clnt)) {
 713		status = PTR_ERR(rpcb_clnt);
 
 
 714		goto bailout_nofree;
 715	}
 716
 717	map = kzalloc(sizeof(struct rpcbind_args), rpc_task_gfp_mask());
 718	if (!map) {
 719		status = -ENOMEM;
 
 
 720		goto bailout_release_client;
 721	}
 722	map->r_prog = clnt->cl_prog;
 723	map->r_vers = clnt->cl_vers;
 724	map->r_prot = xprt->prot;
 725	map->r_port = 0;
 726	map->r_xprt = xprt;
 727	map->r_status = -EIO;
 728
 729	switch (bind_version) {
 730	case RPCBVERS_4:
 731	case RPCBVERS_3:
 732		map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID];
 733		map->r_addr = rpc_sockaddr2uaddr(sap, rpc_task_gfp_mask());
 734		if (!map->r_addr) {
 735			status = -ENOMEM;
 736			goto bailout_free_args;
 737		}
 738		map->r_owner = "";
 739		break;
 740	case RPCBVERS_2:
 741		map->r_addr = NULL;
 742		break;
 743	default:
 744		BUG();
 745	}
 746
 747	child = rpcb_call_async(rpcb_clnt, map, proc);
 748	rpc_release_client(rpcb_clnt);
 
 
 
 
 
 
 749
 750	xprt->stat.bind_count++;
 751	rpc_put_task(child);
 752	return;
 753
 754bailout_free_args:
 755	kfree(map);
 756bailout_release_client:
 757	rpc_release_client(rpcb_clnt);
 758bailout_nofree:
 759	rpcb_wake_rpcbind_waiters(xprt, status);
 760	task->tk_status = status;
 761	xprt_put(xprt);
 762}
 763EXPORT_SYMBOL_GPL(rpcb_getport_async);
 764
 765/*
 766 * Rpcbind child task calls this callback via tk_exit.
 767 */
 768static void rpcb_getport_done(struct rpc_task *child, void *data)
 769{
 770	struct rpcbind_args *map = data;
 771	struct rpc_xprt *xprt = map->r_xprt;
 772
 773	map->r_status = child->tk_status;
 774
 775	/* Garbage reply: retry with a lesser rpcbind version */
 776	if (map->r_status == -EIO)
 777		map->r_status = -EPROTONOSUPPORT;
 778
 779	/* rpcbind server doesn't support this rpcbind protocol version */
 780	if (map->r_status == -EPROTONOSUPPORT)
 781		xprt->bind_index++;
 782
 783	if (map->r_status < 0) {
 784		/* rpcbind server not available on remote host? */
 785		map->r_port = 0;
 786
 787	} else if (map->r_port == 0) {
 788		/* Requested RPC service wasn't registered on remote host */
 789		map->r_status = -EACCES;
 
 790	} else {
 791		/* Succeeded */
 792		map->r_status = 0;
 
 
 793	}
 794
 795	trace_rpcb_setport(child, map->r_status, map->r_port);
 796	xprt->ops->set_port(xprt, map->r_port);
 797	if (map->r_port)
 798		xprt_set_bound(xprt);
 799}
 800
 801/*
 802 * XDR functions for rpcbind
 803 */
 804
 805static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr,
 806			     const void *data)
 807{
 808	const struct rpcbind_args *rpcb = data;
 809	__be32 *p;
 810
 
 
 
 
 
 811	p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2);
 812	*p++ = cpu_to_be32(rpcb->r_prog);
 813	*p++ = cpu_to_be32(rpcb->r_vers);
 814	*p++ = cpu_to_be32(rpcb->r_prot);
 815	*p   = cpu_to_be32(rpcb->r_port);
 816}
 817
 818static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr,
 819			    void *data)
 820{
 821	struct rpcbind_args *rpcb = data;
 822	unsigned long port;
 823	__be32 *p;
 824
 825	rpcb->r_port = 0;
 826
 827	p = xdr_inline_decode(xdr, 4);
 828	if (unlikely(p == NULL))
 829		return -EIO;
 830
 831	port = be32_to_cpup(p);
 
 
 832	if (unlikely(port > USHRT_MAX))
 833		return -EIO;
 834
 835	rpcb->r_port = port;
 836	return 0;
 837}
 838
 839static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr,
 840			void *data)
 841{
 842	unsigned int *boolp = data;
 843	__be32 *p;
 844
 845	p = xdr_inline_decode(xdr, 4);
 846	if (unlikely(p == NULL))
 847		return -EIO;
 848
 849	*boolp = 0;
 850	if (*p != xdr_zero)
 851		*boolp = 1;
 
 
 
 
 
 852	return 0;
 853}
 854
 855static void encode_rpcb_string(struct xdr_stream *xdr, const char *string,
 856			       const u32 maxstrlen)
 857{
 858	__be32 *p;
 859	u32 len;
 860
 861	len = strlen(string);
 862	WARN_ON_ONCE(len > maxstrlen);
 863	if (len > maxstrlen)
 864		/* truncate and hope for the best */
 865		len = maxstrlen;
 866	p = xdr_reserve_space(xdr, 4 + len);
 867	xdr_encode_opaque(p, string, len);
 868}
 869
 870static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 871			     const void *data)
 872{
 873	const struct rpcbind_args *rpcb = data;
 874	__be32 *p;
 875
 
 
 
 
 
 
 876	p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2);
 877	*p++ = cpu_to_be32(rpcb->r_prog);
 878	*p = cpu_to_be32(rpcb->r_vers);
 879
 880	encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN);
 881	encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN);
 882	encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN);
 883}
 884
 885static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 886			    void *data)
 887{
 888	struct rpcbind_args *rpcb = data;
 889	struct sockaddr_storage address;
 890	struct sockaddr *sap = (struct sockaddr *)&address;
 891	__be32 *p;
 892	u32 len;
 893
 894	rpcb->r_port = 0;
 895
 896	p = xdr_inline_decode(xdr, 4);
 897	if (unlikely(p == NULL))
 898		goto out_fail;
 899	len = be32_to_cpup(p);
 900
 901	/*
 902	 * If the returned universal address is a null string,
 903	 * the requested RPC service was not registered.
 904	 */
 905	if (len == 0)
 
 
 906		return 0;
 
 907
 908	if (unlikely(len > RPCBIND_MAXUADDRLEN))
 909		goto out_fail;
 910
 911	p = xdr_inline_decode(xdr, len);
 912	if (unlikely(p == NULL))
 913		goto out_fail;
 
 
 914
 915	if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len,
 916				sap, sizeof(address)) == 0)
 917		goto out_fail;
 918	rpcb->r_port = rpc_get_port(sap);
 919
 920	return 0;
 921
 922out_fail:
 
 
 
 923	return -EIO;
 924}
 925
 926/*
 927 * Not all rpcbind procedures described in RFC 1833 are implemented
 928 * since the Linux kernel RPC code requires only these.
 929 */
 930
 931static const struct rpc_procinfo rpcb_procedures2[] = {
 932	[RPCBPROC_SET] = {
 933		.p_proc		= RPCBPROC_SET,
 934		.p_encode	= rpcb_enc_mapping,
 935		.p_decode	= rpcb_dec_set,
 936		.p_arglen	= RPCB_mappingargs_sz,
 937		.p_replen	= RPCB_setres_sz,
 938		.p_statidx	= RPCBPROC_SET,
 939		.p_timer	= 0,
 940		.p_name		= "SET",
 941	},
 942	[RPCBPROC_UNSET] = {
 943		.p_proc		= RPCBPROC_UNSET,
 944		.p_encode	= rpcb_enc_mapping,
 945		.p_decode	= rpcb_dec_set,
 946		.p_arglen	= RPCB_mappingargs_sz,
 947		.p_replen	= RPCB_setres_sz,
 948		.p_statidx	= RPCBPROC_UNSET,
 949		.p_timer	= 0,
 950		.p_name		= "UNSET",
 951	},
 952	[RPCBPROC_GETPORT] = {
 953		.p_proc		= RPCBPROC_GETPORT,
 954		.p_encode	= rpcb_enc_mapping,
 955		.p_decode	= rpcb_dec_getport,
 956		.p_arglen	= RPCB_mappingargs_sz,
 957		.p_replen	= RPCB_getportres_sz,
 958		.p_statidx	= RPCBPROC_GETPORT,
 959		.p_timer	= 0,
 960		.p_name		= "GETPORT",
 961	},
 962};
 963
 964static const struct rpc_procinfo rpcb_procedures3[] = {
 965	[RPCBPROC_SET] = {
 966		.p_proc		= RPCBPROC_SET,
 967		.p_encode	= rpcb_enc_getaddr,
 968		.p_decode	= rpcb_dec_set,
 969		.p_arglen	= RPCB_getaddrargs_sz,
 970		.p_replen	= RPCB_setres_sz,
 971		.p_statidx	= RPCBPROC_SET,
 972		.p_timer	= 0,
 973		.p_name		= "SET",
 974	},
 975	[RPCBPROC_UNSET] = {
 976		.p_proc		= RPCBPROC_UNSET,
 977		.p_encode	= rpcb_enc_getaddr,
 978		.p_decode	= rpcb_dec_set,
 979		.p_arglen	= RPCB_getaddrargs_sz,
 980		.p_replen	= RPCB_setres_sz,
 981		.p_statidx	= RPCBPROC_UNSET,
 982		.p_timer	= 0,
 983		.p_name		= "UNSET",
 984	},
 985	[RPCBPROC_GETADDR] = {
 986		.p_proc		= RPCBPROC_GETADDR,
 987		.p_encode	= rpcb_enc_getaddr,
 988		.p_decode	= rpcb_dec_getaddr,
 989		.p_arglen	= RPCB_getaddrargs_sz,
 990		.p_replen	= RPCB_getaddrres_sz,
 991		.p_statidx	= RPCBPROC_GETADDR,
 992		.p_timer	= 0,
 993		.p_name		= "GETADDR",
 994	},
 995};
 996
 997static const struct rpc_procinfo rpcb_procedures4[] = {
 998	[RPCBPROC_SET] = {
 999		.p_proc		= RPCBPROC_SET,
1000		.p_encode	= rpcb_enc_getaddr,
1001		.p_decode	= rpcb_dec_set,
1002		.p_arglen	= RPCB_getaddrargs_sz,
1003		.p_replen	= RPCB_setres_sz,
1004		.p_statidx	= RPCBPROC_SET,
1005		.p_timer	= 0,
1006		.p_name		= "SET",
1007	},
1008	[RPCBPROC_UNSET] = {
1009		.p_proc		= RPCBPROC_UNSET,
1010		.p_encode	= rpcb_enc_getaddr,
1011		.p_decode	= rpcb_dec_set,
1012		.p_arglen	= RPCB_getaddrargs_sz,
1013		.p_replen	= RPCB_setres_sz,
1014		.p_statidx	= RPCBPROC_UNSET,
1015		.p_timer	= 0,
1016		.p_name		= "UNSET",
1017	},
1018	[RPCBPROC_GETADDR] = {
1019		.p_proc		= RPCBPROC_GETADDR,
1020		.p_encode	= rpcb_enc_getaddr,
1021		.p_decode	= rpcb_dec_getaddr,
1022		.p_arglen	= RPCB_getaddrargs_sz,
1023		.p_replen	= RPCB_getaddrres_sz,
1024		.p_statidx	= RPCBPROC_GETADDR,
1025		.p_timer	= 0,
1026		.p_name		= "GETADDR",
1027	},
1028};
1029
1030static const struct rpcb_info rpcb_next_version[] = {
1031	{
1032		.rpc_vers	= RPCBVERS_2,
1033		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
1034	},
1035	{
1036		.rpc_proc	= NULL,
1037	},
1038};
1039
1040static const struct rpcb_info rpcb_next_version6[] = {
1041	{
1042		.rpc_vers	= RPCBVERS_4,
1043		.rpc_proc	= &rpcb_procedures4[RPCBPROC_GETADDR],
1044	},
1045	{
1046		.rpc_vers	= RPCBVERS_3,
1047		.rpc_proc	= &rpcb_procedures3[RPCBPROC_GETADDR],
1048	},
1049	{
1050		.rpc_proc	= NULL,
1051	},
1052};
1053
1054static unsigned int rpcb_version2_counts[ARRAY_SIZE(rpcb_procedures2)];
1055static const struct rpc_version rpcb_version2 = {
1056	.number		= RPCBVERS_2,
1057	.nrprocs	= ARRAY_SIZE(rpcb_procedures2),
1058	.procs		= rpcb_procedures2,
1059	.counts		= rpcb_version2_counts,
1060};
1061
1062static unsigned int rpcb_version3_counts[ARRAY_SIZE(rpcb_procedures3)];
1063static const struct rpc_version rpcb_version3 = {
1064	.number		= RPCBVERS_3,
1065	.nrprocs	= ARRAY_SIZE(rpcb_procedures3),
1066	.procs		= rpcb_procedures3,
1067	.counts		= rpcb_version3_counts,
1068};
1069
1070static unsigned int rpcb_version4_counts[ARRAY_SIZE(rpcb_procedures4)];
1071static const struct rpc_version rpcb_version4 = {
1072	.number		= RPCBVERS_4,
1073	.nrprocs	= ARRAY_SIZE(rpcb_procedures4),
1074	.procs		= rpcb_procedures4,
1075	.counts		= rpcb_version4_counts,
1076};
1077
1078static const struct rpc_version *rpcb_version[] = {
1079	NULL,
1080	NULL,
1081	&rpcb_version2,
1082	&rpcb_version3,
1083	&rpcb_version4
1084};
1085
1086static struct rpc_stat rpcb_stats;
1087
1088static const struct rpc_program rpcb_program = {
1089	.name		= "rpcbind",
1090	.number		= RPCBIND_PROGRAM,
1091	.nrvers		= ARRAY_SIZE(rpcb_version),
1092	.version	= rpcb_version,
1093	.stats		= &rpcb_stats,
1094};