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#ifdef RPC_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 *hostname, 359 struct sockaddr *srvaddr, size_t salen, 360 int proto, u32 version) 361{ 362 struct rpc_create_args args = { 363 .net = net, 364 .protocol = proto, 365 .address = srvaddr, 366 .addrsize = salen, 367 .servername = hostname, 368 .program = &rpcb_program, 369 .version = version, 370 .authflavor = RPC_AUTH_UNIX, 371 .flags = (RPC_CLNT_CREATE_NOPING | 372 RPC_CLNT_CREATE_NONPRIVPORT), 373 }; 374 375 switch (srvaddr->sa_family) { 376 case AF_INET: 377 ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT); 378 break; 379 case AF_INET6: 380 ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT); 381 break; 382 default: 383 return ERR_PTR(-EAFNOSUPPORT); 384 } 385 386 return rpc_create(&args); 387} 388 389static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set) 390{ 391 int flags = RPC_TASK_NOCONNECT; 392 int error, result = 0; 393 394 if (is_set || !sn->rpcb_is_af_local) 395 flags = RPC_TASK_SOFTCONN; 396 msg->rpc_resp = &result; 397 398 error = rpc_call_sync(clnt, msg, flags); 399 if (error < 0) { 400 dprintk("RPC: failed to contact local rpcbind " 401 "server (errno %d).\n", -error); 402 return error; 403 } 404 405 if (!result) 406 return -EACCES; 407 return 0; 408} 409 410/** 411 * rpcb_register - set or unset a port registration with the local rpcbind svc 412 * @net: target network namespace 413 * @prog: RPC program number to bind 414 * @vers: RPC version number to bind 415 * @prot: transport protocol to register 416 * @port: port value to register 417 * 418 * Returns zero if the registration request was dispatched successfully 419 * and the rpcbind daemon returned success. Otherwise, returns an errno 420 * value that reflects the nature of the error (request could not be 421 * dispatched, timed out, or rpcbind returned an error). 422 * 423 * RPC services invoke this function to advertise their contact 424 * information via the system's rpcbind daemon. RPC services 425 * invoke this function once for each [program, version, transport] 426 * tuple they wish to advertise. 427 * 428 * Callers may also unregister RPC services that are no longer 429 * available by setting the passed-in port to zero. This removes 430 * all registered transports for [program, version] from the local 431 * rpcbind database. 432 * 433 * This function uses rpcbind protocol version 2 to contact the 434 * local rpcbind daemon. 435 * 436 * Registration works over both AF_INET and AF_INET6, and services 437 * registered via this function are advertised as available for any 438 * address. If the local rpcbind daemon is listening on AF_INET6, 439 * services registered via this function will be advertised on 440 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6 441 * addresses). 442 */ 443int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port) 444{ 445 struct rpcbind_args map = { 446 .r_prog = prog, 447 .r_vers = vers, 448 .r_prot = prot, 449 .r_port = port, 450 }; 451 struct rpc_message msg = { 452 .rpc_argp = &map, 453 }; 454 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 455 bool is_set = false; 456 457 dprintk("RPC: %sregistering (%u, %u, %d, %u) with local " 458 "rpcbind\n", (port ? "" : "un"), 459 prog, vers, prot, port); 460 461 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET]; 462 if (port != 0) { 463 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET]; 464 is_set = true; 465 } 466 467 return rpcb_register_call(sn, sn->rpcb_local_clnt, &msg, is_set); 468} 469 470/* 471 * Fill in AF_INET family-specific arguments to register 472 */ 473static int rpcb_register_inet4(struct sunrpc_net *sn, 474 const struct sockaddr *sap, 475 struct rpc_message *msg) 476{ 477 const struct sockaddr_in *sin = (const struct sockaddr_in *)sap; 478 struct rpcbind_args *map = msg->rpc_argp; 479 unsigned short port = ntohs(sin->sin_port); 480 bool is_set = false; 481 int result; 482 483 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 484 485 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 486 "local rpcbind\n", (port ? "" : "un"), 487 map->r_prog, map->r_vers, 488 map->r_addr, map->r_netid); 489 490 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 491 if (port != 0) { 492 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 493 is_set = true; 494 } 495 496 result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set); 497 kfree(map->r_addr); 498 return result; 499} 500 501/* 502 * Fill in AF_INET6 family-specific arguments to register 503 */ 504static int rpcb_register_inet6(struct sunrpc_net *sn, 505 const struct sockaddr *sap, 506 struct rpc_message *msg) 507{ 508 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap; 509 struct rpcbind_args *map = msg->rpc_argp; 510 unsigned short port = ntohs(sin6->sin6_port); 511 bool is_set = false; 512 int result; 513 514 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 515 516 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 517 "local rpcbind\n", (port ? "" : "un"), 518 map->r_prog, map->r_vers, 519 map->r_addr, map->r_netid); 520 521 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 522 if (port != 0) { 523 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 524 is_set = true; 525 } 526 527 result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set); 528 kfree(map->r_addr); 529 return result; 530} 531 532static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn, 533 struct rpc_message *msg) 534{ 535 struct rpcbind_args *map = msg->rpc_argp; 536 537 dprintk("RPC: unregistering [%u, %u, '%s'] with " 538 "local rpcbind\n", 539 map->r_prog, map->r_vers, map->r_netid); 540 541 map->r_addr = ""; 542 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 543 544 return rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, false); 545} 546 547/** 548 * rpcb_v4_register - set or unset a port registration with the local rpcbind 549 * @net: target network namespace 550 * @program: RPC program number of service to (un)register 551 * @version: RPC version number of service to (un)register 552 * @address: address family, IP address, and port to (un)register 553 * @netid: netid of transport protocol to (un)register 554 * 555 * Returns zero if the registration request was dispatched successfully 556 * and the rpcbind daemon returned success. Otherwise, returns an errno 557 * value that reflects the nature of the error (request could not be 558 * dispatched, timed out, or rpcbind returned an error). 559 * 560 * RPC services invoke this function to advertise their contact 561 * information via the system's rpcbind daemon. RPC services 562 * invoke this function once for each [program, version, address, 563 * netid] tuple they wish to advertise. 564 * 565 * Callers may also unregister RPC services that are registered at a 566 * specific address by setting the port number in @address to zero. 567 * They may unregister all registered protocol families at once for 568 * a service by passing a NULL @address argument. If @netid is "" 569 * then all netids for [program, version, address] are unregistered. 570 * 571 * This function uses rpcbind protocol version 4 to contact the 572 * local rpcbind daemon. The local rpcbind daemon must support 573 * version 4 of the rpcbind protocol in order for these functions 574 * to register a service successfully. 575 * 576 * Supported netids include "udp" and "tcp" for UDP and TCP over 577 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6, 578 * respectively. 579 * 580 * The contents of @address determine the address family and the 581 * port to be registered. The usual practice is to pass INADDR_ANY 582 * as the raw address, but specifying a non-zero address is also 583 * supported by this API if the caller wishes to advertise an RPC 584 * service on a specific network interface. 585 * 586 * Note that passing in INADDR_ANY does not create the same service 587 * registration as IN6ADDR_ANY. The former advertises an RPC 588 * service on any IPv4 address, but not on IPv6. The latter 589 * advertises the service on all IPv4 and IPv6 addresses. 590 */ 591int rpcb_v4_register(struct net *net, const u32 program, const u32 version, 592 const struct sockaddr *address, const char *netid) 593{ 594 struct rpcbind_args map = { 595 .r_prog = program, 596 .r_vers = version, 597 .r_netid = netid, 598 .r_owner = RPCB_OWNER_STRING, 599 }; 600 struct rpc_message msg = { 601 .rpc_argp = &map, 602 }; 603 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 604 605 if (sn->rpcb_local_clnt4 == NULL) 606 return -EPROTONOSUPPORT; 607 608 if (address == NULL) 609 return rpcb_unregister_all_protofamilies(sn, &msg); 610 611 switch (address->sa_family) { 612 case AF_INET: 613 return rpcb_register_inet4(sn, address, &msg); 614 case AF_INET6: 615 return rpcb_register_inet6(sn, address, &msg); 616 } 617 618 return -EAFNOSUPPORT; 619} 620 621static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc) 622{ 623 struct rpc_message msg = { 624 .rpc_proc = proc, 625 .rpc_argp = map, 626 .rpc_resp = map, 627 }; 628 struct rpc_task_setup task_setup_data = { 629 .rpc_client = rpcb_clnt, 630 .rpc_message = &msg, 631 .callback_ops = &rpcb_getport_ops, 632 .callback_data = map, 633 .flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN, 634 }; 635 636 return rpc_run_task(&task_setup_data); 637} 638 639/* 640 * In the case where rpc clients have been cloned, we want to make 641 * sure that we use the program number/version etc of the actual 642 * owner of the xprt. To do so, we walk back up the tree of parents 643 * to find whoever created the transport and/or whoever has the 644 * autobind flag set. 645 */ 646static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt) 647{ 648 struct rpc_clnt *parent = clnt->cl_parent; 649 struct rpc_xprt *xprt = rcu_dereference(clnt->cl_xprt); 650 651 while (parent != clnt) { 652 if (rcu_dereference(parent->cl_xprt) != xprt) 653 break; 654 if (clnt->cl_autobind) 655 break; 656 clnt = parent; 657 parent = parent->cl_parent; 658 } 659 return clnt; 660} 661 662/** 663 * rpcb_getport_async - obtain the port for a given RPC service on a given host 664 * @task: task that is waiting for portmapper request 665 * 666 * This one can be called for an ongoing RPC request, and can be used in 667 * an async (rpciod) context. 668 */ 669void rpcb_getport_async(struct rpc_task *task) 670{ 671 struct rpc_clnt *clnt; 672 struct rpc_procinfo *proc; 673 u32 bind_version; 674 struct rpc_xprt *xprt; 675 struct rpc_clnt *rpcb_clnt; 676 struct rpcbind_args *map; 677 struct rpc_task *child; 678 struct sockaddr_storage addr; 679 struct sockaddr *sap = (struct sockaddr *)&addr; 680 size_t salen; 681 int status; 682 683 rcu_read_lock(); 684 do { 685 clnt = rpcb_find_transport_owner(task->tk_client); 686 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 687 } while (xprt == NULL); 688 rcu_read_unlock(); 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, xprt->servername, sap, salen, 744 xprt->prot, bind_version); 745 if (IS_ERR(rpcb_clnt)) { 746 status = PTR_ERR(rpcb_clnt); 747 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n", 748 task->tk_pid, __func__, PTR_ERR(rpcb_clnt)); 749 goto bailout_nofree; 750 } 751 752 map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC); 753 if (!map) { 754 status = -ENOMEM; 755 dprintk("RPC: %5u %s: no memory available\n", 756 task->tk_pid, __func__); 757 goto bailout_release_client; 758 } 759 map->r_prog = clnt->cl_prog; 760 map->r_vers = clnt->cl_vers; 761 map->r_prot = xprt->prot; 762 map->r_port = 0; 763 map->r_xprt = xprt; 764 map->r_status = -EIO; 765 766 switch (bind_version) { 767 case RPCBVERS_4: 768 case RPCBVERS_3: 769 map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; 770 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC); 771 map->r_owner = ""; 772 break; 773 case RPCBVERS_2: 774 map->r_addr = NULL; 775 break; 776 default: 777 BUG(); 778 } 779 780 child = rpcb_call_async(rpcb_clnt, map, proc); 781 rpc_release_client(rpcb_clnt); 782 if (IS_ERR(child)) { 783 /* rpcb_map_release() has freed the arguments */ 784 dprintk("RPC: %5u %s: rpc_run_task failed\n", 785 task->tk_pid, __func__); 786 return; 787 } 788 789 xprt->stat.bind_count++; 790 rpc_put_task(child); 791 return; 792 793bailout_release_client: 794 rpc_release_client(rpcb_clnt); 795bailout_nofree: 796 rpcb_wake_rpcbind_waiters(xprt, status); 797 task->tk_status = status; 798 xprt_put(xprt); 799} 800EXPORT_SYMBOL_GPL(rpcb_getport_async); 801 802/* 803 * Rpcbind child task calls this callback via tk_exit. 804 */ 805static void rpcb_getport_done(struct rpc_task *child, void *data) 806{ 807 struct rpcbind_args *map = data; 808 struct rpc_xprt *xprt = map->r_xprt; 809 int status = child->tk_status; 810 811 /* Garbage reply: retry with a lesser rpcbind version */ 812 if (status == -EIO) 813 status = -EPROTONOSUPPORT; 814 815 /* rpcbind server doesn't support this rpcbind protocol version */ 816 if (status == -EPROTONOSUPPORT) 817 xprt->bind_index++; 818 819 if (status < 0) { 820 /* rpcbind server not available on remote host? */ 821 xprt->ops->set_port(xprt, 0); 822 } else if (map->r_port == 0) { 823 /* Requested RPC service wasn't registered on remote host */ 824 xprt->ops->set_port(xprt, 0); 825 status = -EACCES; 826 } else { 827 /* Succeeded */ 828 xprt->ops->set_port(xprt, map->r_port); 829 xprt_set_bound(xprt); 830 status = 0; 831 } 832 833 dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n", 834 child->tk_pid, status, map->r_port); 835 836 map->r_status = status; 837} 838 839/* 840 * XDR functions for rpcbind 841 */ 842 843static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, 844 const struct rpcbind_args *rpcb) 845{ 846 __be32 *p; 847 848 dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n", 849 req->rq_task->tk_pid, 850 req->rq_task->tk_msg.rpc_proc->p_name, 851 rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port); 852 853 p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2); 854 *p++ = cpu_to_be32(rpcb->r_prog); 855 *p++ = cpu_to_be32(rpcb->r_vers); 856 *p++ = cpu_to_be32(rpcb->r_prot); 857 *p = cpu_to_be32(rpcb->r_port); 858} 859 860static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr, 861 struct rpcbind_args *rpcb) 862{ 863 unsigned long port; 864 __be32 *p; 865 866 rpcb->r_port = 0; 867 868 p = xdr_inline_decode(xdr, 4); 869 if (unlikely(p == NULL)) 870 return -EIO; 871 872 port = be32_to_cpup(p); 873 dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid, 874 req->rq_task->tk_msg.rpc_proc->p_name, port); 875 if (unlikely(port > USHRT_MAX)) 876 return -EIO; 877 878 rpcb->r_port = port; 879 return 0; 880} 881 882static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr, 883 unsigned int *boolp) 884{ 885 __be32 *p; 886 887 p = xdr_inline_decode(xdr, 4); 888 if (unlikely(p == NULL)) 889 return -EIO; 890 891 *boolp = 0; 892 if (*p != xdr_zero) 893 *boolp = 1; 894 895 dprintk("RPC: %5u RPCB_%s call %s\n", 896 req->rq_task->tk_pid, 897 req->rq_task->tk_msg.rpc_proc->p_name, 898 (*boolp ? "succeeded" : "failed")); 899 return 0; 900} 901 902static void encode_rpcb_string(struct xdr_stream *xdr, const char *string, 903 const u32 maxstrlen) 904{ 905 __be32 *p; 906 u32 len; 907 908 len = strlen(string); 909 WARN_ON_ONCE(len > maxstrlen); 910 if (len > maxstrlen) 911 /* truncate and hope for the best */ 912 len = maxstrlen; 913 p = xdr_reserve_space(xdr, 4 + len); 914 xdr_encode_opaque(p, string, len); 915} 916 917static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 918 const struct rpcbind_args *rpcb) 919{ 920 __be32 *p; 921 922 dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n", 923 req->rq_task->tk_pid, 924 req->rq_task->tk_msg.rpc_proc->p_name, 925 rpcb->r_prog, rpcb->r_vers, 926 rpcb->r_netid, rpcb->r_addr); 927 928 p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2); 929 *p++ = cpu_to_be32(rpcb->r_prog); 930 *p = cpu_to_be32(rpcb->r_vers); 931 932 encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN); 933 encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN); 934 encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN); 935} 936 937static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 938 struct rpcbind_args *rpcb) 939{ 940 struct sockaddr_storage address; 941 struct sockaddr *sap = (struct sockaddr *)&address; 942 __be32 *p; 943 u32 len; 944 945 rpcb->r_port = 0; 946 947 p = xdr_inline_decode(xdr, 4); 948 if (unlikely(p == NULL)) 949 goto out_fail; 950 len = be32_to_cpup(p); 951 952 /* 953 * If the returned universal address is a null string, 954 * the requested RPC service was not registered. 955 */ 956 if (len == 0) { 957 dprintk("RPC: %5u RPCB reply: program not registered\n", 958 req->rq_task->tk_pid); 959 return 0; 960 } 961 962 if (unlikely(len > RPCBIND_MAXUADDRLEN)) 963 goto out_fail; 964 965 p = xdr_inline_decode(xdr, len); 966 if (unlikely(p == NULL)) 967 goto out_fail; 968 dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid, 969 req->rq_task->tk_msg.rpc_proc->p_name, (char *)p); 970 971 if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len, 972 sap, sizeof(address)) == 0) 973 goto out_fail; 974 rpcb->r_port = rpc_get_port(sap); 975 976 return 0; 977 978out_fail: 979 dprintk("RPC: %5u malformed RPCB_%s reply\n", 980 req->rq_task->tk_pid, 981 req->rq_task->tk_msg.rpc_proc->p_name); 982 return -EIO; 983} 984 985/* 986 * Not all rpcbind procedures described in RFC 1833 are implemented 987 * since the Linux kernel RPC code requires only these. 988 */ 989 990static struct rpc_procinfo rpcb_procedures2[] = { 991 [RPCBPROC_SET] = { 992 .p_proc = RPCBPROC_SET, 993 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 994 .p_decode = (kxdrdproc_t)rpcb_dec_set, 995 .p_arglen = RPCB_mappingargs_sz, 996 .p_replen = RPCB_setres_sz, 997 .p_statidx = RPCBPROC_SET, 998 .p_timer = 0, 999 .p_name = "SET", 1000 }, 1001 [RPCBPROC_UNSET] = { 1002 .p_proc = RPCBPROC_UNSET, 1003 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 1004 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1005 .p_arglen = RPCB_mappingargs_sz, 1006 .p_replen = RPCB_setres_sz, 1007 .p_statidx = RPCBPROC_UNSET, 1008 .p_timer = 0, 1009 .p_name = "UNSET", 1010 }, 1011 [RPCBPROC_GETPORT] = { 1012 .p_proc = RPCBPROC_GETPORT, 1013 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 1014 .p_decode = (kxdrdproc_t)rpcb_dec_getport, 1015 .p_arglen = RPCB_mappingargs_sz, 1016 .p_replen = RPCB_getportres_sz, 1017 .p_statidx = RPCBPROC_GETPORT, 1018 .p_timer = 0, 1019 .p_name = "GETPORT", 1020 }, 1021}; 1022 1023static struct rpc_procinfo rpcb_procedures3[] = { 1024 [RPCBPROC_SET] = { 1025 .p_proc = RPCBPROC_SET, 1026 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1027 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1028 .p_arglen = RPCB_getaddrargs_sz, 1029 .p_replen = RPCB_setres_sz, 1030 .p_statidx = RPCBPROC_SET, 1031 .p_timer = 0, 1032 .p_name = "SET", 1033 }, 1034 [RPCBPROC_UNSET] = { 1035 .p_proc = RPCBPROC_UNSET, 1036 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1037 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1038 .p_arglen = RPCB_getaddrargs_sz, 1039 .p_replen = RPCB_setres_sz, 1040 .p_statidx = RPCBPROC_UNSET, 1041 .p_timer = 0, 1042 .p_name = "UNSET", 1043 }, 1044 [RPCBPROC_GETADDR] = { 1045 .p_proc = RPCBPROC_GETADDR, 1046 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1047 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1048 .p_arglen = RPCB_getaddrargs_sz, 1049 .p_replen = RPCB_getaddrres_sz, 1050 .p_statidx = RPCBPROC_GETADDR, 1051 .p_timer = 0, 1052 .p_name = "GETADDR", 1053 }, 1054}; 1055 1056static struct rpc_procinfo rpcb_procedures4[] = { 1057 [RPCBPROC_SET] = { 1058 .p_proc = RPCBPROC_SET, 1059 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1060 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1061 .p_arglen = RPCB_getaddrargs_sz, 1062 .p_replen = RPCB_setres_sz, 1063 .p_statidx = RPCBPROC_SET, 1064 .p_timer = 0, 1065 .p_name = "SET", 1066 }, 1067 [RPCBPROC_UNSET] = { 1068 .p_proc = RPCBPROC_UNSET, 1069 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1070 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1071 .p_arglen = RPCB_getaddrargs_sz, 1072 .p_replen = RPCB_setres_sz, 1073 .p_statidx = RPCBPROC_UNSET, 1074 .p_timer = 0, 1075 .p_name = "UNSET", 1076 }, 1077 [RPCBPROC_GETADDR] = { 1078 .p_proc = RPCBPROC_GETADDR, 1079 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1080 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1081 .p_arglen = RPCB_getaddrargs_sz, 1082 .p_replen = RPCB_getaddrres_sz, 1083 .p_statidx = RPCBPROC_GETADDR, 1084 .p_timer = 0, 1085 .p_name = "GETADDR", 1086 }, 1087}; 1088 1089static const struct rpcb_info rpcb_next_version[] = { 1090 { 1091 .rpc_vers = RPCBVERS_2, 1092 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT], 1093 }, 1094 { 1095 .rpc_proc = NULL, 1096 }, 1097}; 1098 1099static const struct rpcb_info rpcb_next_version6[] = { 1100 { 1101 .rpc_vers = RPCBVERS_4, 1102 .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR], 1103 }, 1104 { 1105 .rpc_vers = RPCBVERS_3, 1106 .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR], 1107 }, 1108 { 1109 .rpc_proc = NULL, 1110 }, 1111}; 1112 1113static const struct rpc_version rpcb_version2 = { 1114 .number = RPCBVERS_2, 1115 .nrprocs = ARRAY_SIZE(rpcb_procedures2), 1116 .procs = rpcb_procedures2 1117}; 1118 1119static const struct rpc_version rpcb_version3 = { 1120 .number = RPCBVERS_3, 1121 .nrprocs = ARRAY_SIZE(rpcb_procedures3), 1122 .procs = rpcb_procedures3 1123}; 1124 1125static const struct rpc_version rpcb_version4 = { 1126 .number = RPCBVERS_4, 1127 .nrprocs = ARRAY_SIZE(rpcb_procedures4), 1128 .procs = rpcb_procedures4 1129}; 1130 1131static const struct rpc_version *rpcb_version[] = { 1132 NULL, 1133 NULL, 1134 &rpcb_version2, 1135 &rpcb_version3, 1136 &rpcb_version4 1137}; 1138 1139static struct rpc_stat rpcb_stats; 1140 1141static const struct rpc_program rpcb_program = { 1142 .name = "rpcbind", 1143 .number = RPCBIND_PROGRAM, 1144 .nrvers = ARRAY_SIZE(rpcb_version), 1145 .version = rpcb_version, 1146 .stats = &rpcb_stats, 1147}; 1148