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 *xprt = rcu_dereference(clnt->cl_xprt); 652 653 while (parent != clnt) { 654 if (rcu_dereference(parent->cl_xprt) != xprt) 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 do { 687 clnt = rpcb_find_transport_owner(task->tk_client); 688 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 689 } while (xprt == NULL); 690 rcu_read_unlock(); 691 692 dprintk("RPC: %5u %s(%s, %u, %u, %d)\n", 693 task->tk_pid, __func__, 694 xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot); 695 696 /* Put self on the wait queue to ensure we get notified if 697 * some other task is already attempting to bind the port */ 698 rpc_sleep_on(&xprt->binding, task, NULL); 699 700 if (xprt_test_and_set_binding(xprt)) { 701 dprintk("RPC: %5u %s: waiting for another binder\n", 702 task->tk_pid, __func__); 703 xprt_put(xprt); 704 return; 705 } 706 707 /* Someone else may have bound if we slept */ 708 if (xprt_bound(xprt)) { 709 status = 0; 710 dprintk("RPC: %5u %s: already bound\n", 711 task->tk_pid, __func__); 712 goto bailout_nofree; 713 } 714 715 /* Parent transport's destination address */ 716 salen = rpc_peeraddr(clnt, sap, sizeof(addr)); 717 718 /* Don't ever use rpcbind v2 for AF_INET6 requests */ 719 switch (sap->sa_family) { 720 case AF_INET: 721 proc = rpcb_next_version[xprt->bind_index].rpc_proc; 722 bind_version = rpcb_next_version[xprt->bind_index].rpc_vers; 723 break; 724 case AF_INET6: 725 proc = rpcb_next_version6[xprt->bind_index].rpc_proc; 726 bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers; 727 break; 728 default: 729 status = -EAFNOSUPPORT; 730 dprintk("RPC: %5u %s: bad address family\n", 731 task->tk_pid, __func__); 732 goto bailout_nofree; 733 } 734 if (proc == NULL) { 735 xprt->bind_index = 0; 736 status = -EPFNOSUPPORT; 737 dprintk("RPC: %5u %s: no more getport versions available\n", 738 task->tk_pid, __func__); 739 goto bailout_nofree; 740 } 741 742 dprintk("RPC: %5u %s: trying rpcbind version %u\n", 743 task->tk_pid, __func__, bind_version); 744 745 rpcb_clnt = rpcb_create(xprt->xprt_net, 746 clnt->cl_nodename, 747 xprt->servername, sap, salen, 748 xprt->prot, bind_version); 749 if (IS_ERR(rpcb_clnt)) { 750 status = PTR_ERR(rpcb_clnt); 751 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n", 752 task->tk_pid, __func__, PTR_ERR(rpcb_clnt)); 753 goto bailout_nofree; 754 } 755 756 map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC); 757 if (!map) { 758 status = -ENOMEM; 759 dprintk("RPC: %5u %s: no memory available\n", 760 task->tk_pid, __func__); 761 goto bailout_release_client; 762 } 763 map->r_prog = clnt->cl_prog; 764 map->r_vers = clnt->cl_vers; 765 map->r_prot = xprt->prot; 766 map->r_port = 0; 767 map->r_xprt = xprt; 768 map->r_status = -EIO; 769 770 switch (bind_version) { 771 case RPCBVERS_4: 772 case RPCBVERS_3: 773 map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; 774 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC); 775 map->r_owner = ""; 776 break; 777 case RPCBVERS_2: 778 map->r_addr = NULL; 779 break; 780 default: 781 BUG(); 782 } 783 784 child = rpcb_call_async(rpcb_clnt, map, proc); 785 rpc_release_client(rpcb_clnt); 786 if (IS_ERR(child)) { 787 /* rpcb_map_release() has freed the arguments */ 788 dprintk("RPC: %5u %s: rpc_run_task failed\n", 789 task->tk_pid, __func__); 790 return; 791 } 792 793 xprt->stat.bind_count++; 794 rpc_put_task(child); 795 return; 796 797bailout_release_client: 798 rpc_release_client(rpcb_clnt); 799bailout_nofree: 800 rpcb_wake_rpcbind_waiters(xprt, status); 801 task->tk_status = status; 802 xprt_put(xprt); 803} 804EXPORT_SYMBOL_GPL(rpcb_getport_async); 805 806/* 807 * Rpcbind child task calls this callback via tk_exit. 808 */ 809static void rpcb_getport_done(struct rpc_task *child, void *data) 810{ 811 struct rpcbind_args *map = data; 812 struct rpc_xprt *xprt = map->r_xprt; 813 int status = child->tk_status; 814 815 /* Garbage reply: retry with a lesser rpcbind version */ 816 if (status == -EIO) 817 status = -EPROTONOSUPPORT; 818 819 /* rpcbind server doesn't support this rpcbind protocol version */ 820 if (status == -EPROTONOSUPPORT) 821 xprt->bind_index++; 822 823 if (status < 0) { 824 /* rpcbind server not available on remote host? */ 825 xprt->ops->set_port(xprt, 0); 826 } else if (map->r_port == 0) { 827 /* Requested RPC service wasn't registered on remote host */ 828 xprt->ops->set_port(xprt, 0); 829 status = -EACCES; 830 } else { 831 /* Succeeded */ 832 xprt->ops->set_port(xprt, map->r_port); 833 xprt_set_bound(xprt); 834 status = 0; 835 } 836 837 dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n", 838 child->tk_pid, status, map->r_port); 839 840 map->r_status = status; 841} 842 843/* 844 * XDR functions for rpcbind 845 */ 846 847static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, 848 const struct rpcbind_args *rpcb) 849{ 850 __be32 *p; 851 852 dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n", 853 req->rq_task->tk_pid, 854 req->rq_task->tk_msg.rpc_proc->p_name, 855 rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port); 856 857 p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2); 858 *p++ = cpu_to_be32(rpcb->r_prog); 859 *p++ = cpu_to_be32(rpcb->r_vers); 860 *p++ = cpu_to_be32(rpcb->r_prot); 861 *p = cpu_to_be32(rpcb->r_port); 862} 863 864static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr, 865 struct rpcbind_args *rpcb) 866{ 867 unsigned long port; 868 __be32 *p; 869 870 rpcb->r_port = 0; 871 872 p = xdr_inline_decode(xdr, 4); 873 if (unlikely(p == NULL)) 874 return -EIO; 875 876 port = be32_to_cpup(p); 877 dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid, 878 req->rq_task->tk_msg.rpc_proc->p_name, port); 879 if (unlikely(port > USHRT_MAX)) 880 return -EIO; 881 882 rpcb->r_port = port; 883 return 0; 884} 885 886static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr, 887 unsigned int *boolp) 888{ 889 __be32 *p; 890 891 p = xdr_inline_decode(xdr, 4); 892 if (unlikely(p == NULL)) 893 return -EIO; 894 895 *boolp = 0; 896 if (*p != xdr_zero) 897 *boolp = 1; 898 899 dprintk("RPC: %5u RPCB_%s call %s\n", 900 req->rq_task->tk_pid, 901 req->rq_task->tk_msg.rpc_proc->p_name, 902 (*boolp ? "succeeded" : "failed")); 903 return 0; 904} 905 906static void encode_rpcb_string(struct xdr_stream *xdr, const char *string, 907 const u32 maxstrlen) 908{ 909 __be32 *p; 910 u32 len; 911 912 len = strlen(string); 913 WARN_ON_ONCE(len > maxstrlen); 914 if (len > maxstrlen) 915 /* truncate and hope for the best */ 916 len = maxstrlen; 917 p = xdr_reserve_space(xdr, 4 + len); 918 xdr_encode_opaque(p, string, len); 919} 920 921static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 922 const struct rpcbind_args *rpcb) 923{ 924 __be32 *p; 925 926 dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n", 927 req->rq_task->tk_pid, 928 req->rq_task->tk_msg.rpc_proc->p_name, 929 rpcb->r_prog, rpcb->r_vers, 930 rpcb->r_netid, rpcb->r_addr); 931 932 p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2); 933 *p++ = cpu_to_be32(rpcb->r_prog); 934 *p = cpu_to_be32(rpcb->r_vers); 935 936 encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN); 937 encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN); 938 encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN); 939} 940 941static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 942 struct rpcbind_args *rpcb) 943{ 944 struct sockaddr_storage address; 945 struct sockaddr *sap = (struct sockaddr *)&address; 946 __be32 *p; 947 u32 len; 948 949 rpcb->r_port = 0; 950 951 p = xdr_inline_decode(xdr, 4); 952 if (unlikely(p == NULL)) 953 goto out_fail; 954 len = be32_to_cpup(p); 955 956 /* 957 * If the returned universal address is a null string, 958 * the requested RPC service was not registered. 959 */ 960 if (len == 0) { 961 dprintk("RPC: %5u RPCB reply: program not registered\n", 962 req->rq_task->tk_pid); 963 return 0; 964 } 965 966 if (unlikely(len > RPCBIND_MAXUADDRLEN)) 967 goto out_fail; 968 969 p = xdr_inline_decode(xdr, len); 970 if (unlikely(p == NULL)) 971 goto out_fail; 972 dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid, 973 req->rq_task->tk_msg.rpc_proc->p_name, (char *)p); 974 975 if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len, 976 sap, sizeof(address)) == 0) 977 goto out_fail; 978 rpcb->r_port = rpc_get_port(sap); 979 980 return 0; 981 982out_fail: 983 dprintk("RPC: %5u malformed RPCB_%s reply\n", 984 req->rq_task->tk_pid, 985 req->rq_task->tk_msg.rpc_proc->p_name); 986 return -EIO; 987} 988 989/* 990 * Not all rpcbind procedures described in RFC 1833 are implemented 991 * since the Linux kernel RPC code requires only these. 992 */ 993 994static struct rpc_procinfo rpcb_procedures2[] = { 995 [RPCBPROC_SET] = { 996 .p_proc = RPCBPROC_SET, 997 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 998 .p_decode = (kxdrdproc_t)rpcb_dec_set, 999 .p_arglen = RPCB_mappingargs_sz, 1000 .p_replen = RPCB_setres_sz, 1001 .p_statidx = RPCBPROC_SET, 1002 .p_timer = 0, 1003 .p_name = "SET", 1004 }, 1005 [RPCBPROC_UNSET] = { 1006 .p_proc = RPCBPROC_UNSET, 1007 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 1008 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1009 .p_arglen = RPCB_mappingargs_sz, 1010 .p_replen = RPCB_setres_sz, 1011 .p_statidx = RPCBPROC_UNSET, 1012 .p_timer = 0, 1013 .p_name = "UNSET", 1014 }, 1015 [RPCBPROC_GETPORT] = { 1016 .p_proc = RPCBPROC_GETPORT, 1017 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 1018 .p_decode = (kxdrdproc_t)rpcb_dec_getport, 1019 .p_arglen = RPCB_mappingargs_sz, 1020 .p_replen = RPCB_getportres_sz, 1021 .p_statidx = RPCBPROC_GETPORT, 1022 .p_timer = 0, 1023 .p_name = "GETPORT", 1024 }, 1025}; 1026 1027static struct rpc_procinfo rpcb_procedures3[] = { 1028 [RPCBPROC_SET] = { 1029 .p_proc = RPCBPROC_SET, 1030 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1031 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1032 .p_arglen = RPCB_getaddrargs_sz, 1033 .p_replen = RPCB_setres_sz, 1034 .p_statidx = RPCBPROC_SET, 1035 .p_timer = 0, 1036 .p_name = "SET", 1037 }, 1038 [RPCBPROC_UNSET] = { 1039 .p_proc = RPCBPROC_UNSET, 1040 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1041 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1042 .p_arglen = RPCB_getaddrargs_sz, 1043 .p_replen = RPCB_setres_sz, 1044 .p_statidx = RPCBPROC_UNSET, 1045 .p_timer = 0, 1046 .p_name = "UNSET", 1047 }, 1048 [RPCBPROC_GETADDR] = { 1049 .p_proc = RPCBPROC_GETADDR, 1050 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1051 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1052 .p_arglen = RPCB_getaddrargs_sz, 1053 .p_replen = RPCB_getaddrres_sz, 1054 .p_statidx = RPCBPROC_GETADDR, 1055 .p_timer = 0, 1056 .p_name = "GETADDR", 1057 }, 1058}; 1059 1060static struct rpc_procinfo rpcb_procedures4[] = { 1061 [RPCBPROC_SET] = { 1062 .p_proc = RPCBPROC_SET, 1063 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1064 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1065 .p_arglen = RPCB_getaddrargs_sz, 1066 .p_replen = RPCB_setres_sz, 1067 .p_statidx = RPCBPROC_SET, 1068 .p_timer = 0, 1069 .p_name = "SET", 1070 }, 1071 [RPCBPROC_UNSET] = { 1072 .p_proc = RPCBPROC_UNSET, 1073 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1074 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1075 .p_arglen = RPCB_getaddrargs_sz, 1076 .p_replen = RPCB_setres_sz, 1077 .p_statidx = RPCBPROC_UNSET, 1078 .p_timer = 0, 1079 .p_name = "UNSET", 1080 }, 1081 [RPCBPROC_GETADDR] = { 1082 .p_proc = RPCBPROC_GETADDR, 1083 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1084 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1085 .p_arglen = RPCB_getaddrargs_sz, 1086 .p_replen = RPCB_getaddrres_sz, 1087 .p_statidx = RPCBPROC_GETADDR, 1088 .p_timer = 0, 1089 .p_name = "GETADDR", 1090 }, 1091}; 1092 1093static const struct rpcb_info rpcb_next_version[] = { 1094 { 1095 .rpc_vers = RPCBVERS_2, 1096 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT], 1097 }, 1098 { 1099 .rpc_proc = NULL, 1100 }, 1101}; 1102 1103static const struct rpcb_info rpcb_next_version6[] = { 1104 { 1105 .rpc_vers = RPCBVERS_4, 1106 .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR], 1107 }, 1108 { 1109 .rpc_vers = RPCBVERS_3, 1110 .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR], 1111 }, 1112 { 1113 .rpc_proc = NULL, 1114 }, 1115}; 1116 1117static const struct rpc_version rpcb_version2 = { 1118 .number = RPCBVERS_2, 1119 .nrprocs = ARRAY_SIZE(rpcb_procedures2), 1120 .procs = rpcb_procedures2 1121}; 1122 1123static const struct rpc_version rpcb_version3 = { 1124 .number = RPCBVERS_3, 1125 .nrprocs = ARRAY_SIZE(rpcb_procedures3), 1126 .procs = rpcb_procedures3 1127}; 1128 1129static const struct rpc_version rpcb_version4 = { 1130 .number = RPCBVERS_4, 1131 .nrprocs = ARRAY_SIZE(rpcb_procedures4), 1132 .procs = rpcb_procedures4 1133}; 1134 1135static const struct rpc_version *rpcb_version[] = { 1136 NULL, 1137 NULL, 1138 &rpcb_version2, 1139 &rpcb_version3, 1140 &rpcb_version4 1141}; 1142 1143static struct rpc_stat rpcb_stats; 1144 1145static const struct rpc_program rpcb_program = { 1146 .name = "rpcbind", 1147 .number = RPCBIND_PROGRAM, 1148 .nrvers = ARRAY_SIZE(rpcb_version), 1149 .version = rpcb_version, 1150 .stats = &rpcb_stats, 1151}; 1152