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 47 enum { 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 111 112 static void rpcb_getport_done(struct rpc_task *, void *); 113 static void rpcb_map_release(void *data); 114 static const struct rpc_program rpcb_program; 115 116 struct 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 }; 129 130 static const struct rpc_procinfo rpcb_procedures2[]; 131 static const struct rpc_procinfo rpcb_procedures3[]; 132 static const struct rpc_procinfo rpcb_procedures4[]; 133 134 struct rpcb_info { 135 u32 rpc_vers; 136 const struct rpc_procinfo *rpc_proc; 137 }; 138 139 static const struct rpcb_info rpcb_next_version[]; 140 static const struct rpcb_info rpcb_next_version6[]; 141 142 static const struct rpc_call_ops rpcb_getport_ops = { 143 .rpc_call_done = rpcb_getport_done, 144 .rpc_release = rpcb_map_release, 145 }; 146 147 static 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 } 152 153 static 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 } 162 163 static 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 } 176 177 void 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 } 204 205 static 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 */ 223 static 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); 267 268 out: 269 return result; 270 } 271 272 /* 273 * Returns zero on success, otherwise a negative errno value 274 * is returned. 275 */ 276 static 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); 314 315 out: 316 return result; 317 } 318 319 /* 320 * Returns zero on success, otherwise a negative errno value 321 * is returned. 322 */ 323 int 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); 337 338 out: 339 mutex_unlock(&rpcb_create_local_mutex); 340 return result; 341 } 342 343 static 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 } 379 380 static 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 */ 431 int 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 */ 459 static 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 */ 485 static 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 } 507 508 static 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 */ 565 int 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 } 596 597 static 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 */ 623 static 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 */ 646 void 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), GFP_NOFS); 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, GFP_NOFS); 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; 753 754 bailout_free_args: 755 kfree(map); 756 bailout_release_client: 757 rpc_release_client(rpcb_clnt); 758 bailout_nofree: 759 rpcb_wake_rpcbind_waiters(xprt, status); 760 task->tk_status = status; 761 xprt_put(xprt); 762 } 763 EXPORT_SYMBOL_GPL(rpcb_getport_async); 764 765 /* 766 * Rpcbind child task calls this callback via tk_exit. 767 */ 768 static 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 */ 804 805 static 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 } 817 818 static 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 } 838 839 static 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 } 854 855 static 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 } 869 870 static 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 } 884 885 static 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; 921 922 out_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 */ 930 931 static 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 }; 963 964 static 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 }; 996 997 static 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 1030 static 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 1040 static 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 1054 static unsigned int rpcb_version2_counts[ARRAY_SIZE(rpcb_procedures2)]; 1055 static 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 1062 static unsigned int rpcb_version3_counts[ARRAY_SIZE(rpcb_procedures3)]; 1063 static 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 1070 static unsigned int rpcb_version4_counts[ARRAY_SIZE(rpcb_procedures4)]; 1071 static 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 1078 static const struct rpc_version *rpcb_version[] = { 1079 NULL, 1080 NULL, 1081 &rpcb_version2, 1082 &rpcb_version3, 1083 &rpcb_version4 1084 }; 1085 1086 static struct rpc_stat rpcb_stats; 1087 1088 static 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 }; 1095