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/sched.h> 30 #include <linux/sunrpc/xprtsock.h> 31 32 #include "netns.h" 33 34 #ifdef RPC_DEBUG 35 # define RPCDBG_FACILITY RPCDBG_BIND 36 #endif 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 struct rpc_procinfo rpcb_procedures2[]; 131 static struct rpc_procinfo rpcb_procedures3[]; 132 static struct rpc_procinfo rpcb_procedures4[]; 133 134 struct rpcb_info { 135 u32 rpc_vers; 136 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 { 208 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 209 210 /* Protected by rpcb_create_local_mutex */ 211 sn->rpcb_local_clnt = clnt; 212 sn->rpcb_local_clnt4 = clnt4; 213 smp_wmb(); 214 sn->rpcb_users = 1; 215 dprintk("RPC: created new rpcb local clients (rpcb_local_clnt: " 216 "%p, rpcb_local_clnt4: %p) for net %p%s\n", 217 sn->rpcb_local_clnt, sn->rpcb_local_clnt4, 218 net, (net == &init_net) ? " (init_net)" : ""); 219 } 220 221 /* 222 * Returns zero on success, otherwise a negative errno value 223 * is returned. 224 */ 225 static int rpcb_create_local_unix(struct net *net) 226 { 227 static const struct sockaddr_un rpcb_localaddr_rpcbind = { 228 .sun_family = AF_LOCAL, 229 .sun_path = RPCBIND_SOCK_PATHNAME, 230 }; 231 struct rpc_create_args args = { 232 .net = net, 233 .protocol = XPRT_TRANSPORT_LOCAL, 234 .address = (struct sockaddr *)&rpcb_localaddr_rpcbind, 235 .addrsize = sizeof(rpcb_localaddr_rpcbind), 236 .servername = "localhost", 237 .program = &rpcb_program, 238 .version = RPCBVERS_2, 239 .authflavor = RPC_AUTH_NULL, 240 }; 241 struct rpc_clnt *clnt, *clnt4; 242 int result = 0; 243 244 /* 245 * Because we requested an RPC PING at transport creation time, 246 * this works only if the user space portmapper is rpcbind, and 247 * it's listening on AF_LOCAL on the named socket. 248 */ 249 clnt = rpc_create(&args); 250 if (IS_ERR(clnt)) { 251 dprintk("RPC: failed to create AF_LOCAL rpcbind " 252 "client (errno %ld).\n", PTR_ERR(clnt)); 253 result = PTR_ERR(clnt); 254 goto out; 255 } 256 257 clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); 258 if (IS_ERR(clnt4)) { 259 dprintk("RPC: failed to bind second program to " 260 "rpcbind v4 client (errno %ld).\n", 261 PTR_ERR(clnt4)); 262 clnt4 = NULL; 263 } 264 265 rpcb_set_local(net, clnt, clnt4); 266 267 out: 268 return result; 269 } 270 271 /* 272 * Returns zero on success, otherwise a negative errno value 273 * is returned. 274 */ 275 static int rpcb_create_local_net(struct net *net) 276 { 277 static const struct sockaddr_in rpcb_inaddr_loopback = { 278 .sin_family = AF_INET, 279 .sin_addr.s_addr = htonl(INADDR_LOOPBACK), 280 .sin_port = htons(RPCBIND_PORT), 281 }; 282 struct rpc_create_args args = { 283 .net = net, 284 .protocol = XPRT_TRANSPORT_TCP, 285 .address = (struct sockaddr *)&rpcb_inaddr_loopback, 286 .addrsize = sizeof(rpcb_inaddr_loopback), 287 .servername = "localhost", 288 .program = &rpcb_program, 289 .version = RPCBVERS_2, 290 .authflavor = RPC_AUTH_UNIX, 291 .flags = RPC_CLNT_CREATE_NOPING, 292 }; 293 struct rpc_clnt *clnt, *clnt4; 294 int result = 0; 295 296 clnt = rpc_create(&args); 297 if (IS_ERR(clnt)) { 298 dprintk("RPC: failed to create local rpcbind " 299 "client (errno %ld).\n", PTR_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 dprintk("RPC: failed to bind second program to " 312 "rpcbind v4 client (errno %ld).\n", 313 PTR_ERR(clnt4)); 314 clnt4 = NULL; 315 } 316 317 rpcb_set_local(net, clnt, clnt4); 318 319 out: 320 return result; 321 } 322 323 /* 324 * Returns zero on success, otherwise a negative errno value 325 * is returned. 326 */ 327 int rpcb_create_local(struct net *net) 328 { 329 static DEFINE_MUTEX(rpcb_create_local_mutex); 330 int result = 0; 331 332 if (rpcb_get_local(net)) 333 return result; 334 335 mutex_lock(&rpcb_create_local_mutex); 336 if (rpcb_get_local(net)) 337 goto out; 338 339 if (rpcb_create_local_unix(net) != 0) 340 result = rpcb_create_local_net(net); 341 342 out: 343 mutex_unlock(&rpcb_create_local_mutex); 344 return result; 345 } 346 347 static struct rpc_clnt *rpcb_create(struct net *net, const char *hostname, 348 struct sockaddr *srvaddr, size_t salen, 349 int proto, u32 version) 350 { 351 struct rpc_create_args args = { 352 .net = net, 353 .protocol = proto, 354 .address = srvaddr, 355 .addrsize = salen, 356 .servername = hostname, 357 .program = &rpcb_program, 358 .version = version, 359 .authflavor = RPC_AUTH_UNIX, 360 .flags = (RPC_CLNT_CREATE_NOPING | 361 RPC_CLNT_CREATE_NONPRIVPORT), 362 }; 363 364 switch (srvaddr->sa_family) { 365 case AF_INET: 366 ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT); 367 break; 368 case AF_INET6: 369 ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT); 370 break; 371 default: 372 return ERR_PTR(-EAFNOSUPPORT); 373 } 374 375 return rpc_create(&args); 376 } 377 378 static int rpcb_register_call(struct rpc_clnt *clnt, struct rpc_message *msg) 379 { 380 int result, error = 0; 381 382 msg->rpc_resp = &result; 383 384 error = rpc_call_sync(clnt, msg, RPC_TASK_SOFTCONN); 385 if (error < 0) { 386 dprintk("RPC: failed to contact local rpcbind " 387 "server (errno %d).\n", -error); 388 return error; 389 } 390 391 if (!result) 392 return -EACCES; 393 return 0; 394 } 395 396 /** 397 * rpcb_register - set or unset a port registration with the local rpcbind svc 398 * @net: target network namespace 399 * @prog: RPC program number to bind 400 * @vers: RPC version number to bind 401 * @prot: transport protocol to register 402 * @port: port value to register 403 * 404 * Returns zero if the registration request was dispatched successfully 405 * and the rpcbind daemon returned success. Otherwise, returns an errno 406 * value that reflects the nature of the error (request could not be 407 * dispatched, timed out, or rpcbind returned an error). 408 * 409 * RPC services invoke this function to advertise their contact 410 * information via the system's rpcbind daemon. RPC services 411 * invoke this function once for each [program, version, transport] 412 * tuple they wish to advertise. 413 * 414 * Callers may also unregister RPC services that are no longer 415 * available by setting the passed-in port to zero. This removes 416 * all registered transports for [program, version] from the local 417 * rpcbind database. 418 * 419 * This function uses rpcbind protocol version 2 to contact the 420 * local rpcbind daemon. 421 * 422 * Registration works over both AF_INET and AF_INET6, and services 423 * registered via this function are advertised as available for any 424 * address. If the local rpcbind daemon is listening on AF_INET6, 425 * services registered via this function will be advertised on 426 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6 427 * addresses). 428 */ 429 int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port) 430 { 431 struct rpcbind_args map = { 432 .r_prog = prog, 433 .r_vers = vers, 434 .r_prot = prot, 435 .r_port = port, 436 }; 437 struct rpc_message msg = { 438 .rpc_argp = &map, 439 }; 440 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 441 442 dprintk("RPC: %sregistering (%u, %u, %d, %u) with local " 443 "rpcbind\n", (port ? "" : "un"), 444 prog, vers, prot, port); 445 446 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET]; 447 if (port) 448 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET]; 449 450 return rpcb_register_call(sn->rpcb_local_clnt, &msg); 451 } 452 453 /* 454 * Fill in AF_INET family-specific arguments to register 455 */ 456 static int rpcb_register_inet4(struct sunrpc_net *sn, 457 const struct sockaddr *sap, 458 struct rpc_message *msg) 459 { 460 const struct sockaddr_in *sin = (const struct sockaddr_in *)sap; 461 struct rpcbind_args *map = msg->rpc_argp; 462 unsigned short port = ntohs(sin->sin_port); 463 int result; 464 465 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 466 467 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 468 "local rpcbind\n", (port ? "" : "un"), 469 map->r_prog, map->r_vers, 470 map->r_addr, map->r_netid); 471 472 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 473 if (port) 474 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 475 476 result = rpcb_register_call(sn->rpcb_local_clnt4, msg); 477 kfree(map->r_addr); 478 return result; 479 } 480 481 /* 482 * Fill in AF_INET6 family-specific arguments to register 483 */ 484 static int rpcb_register_inet6(struct sunrpc_net *sn, 485 const struct sockaddr *sap, 486 struct rpc_message *msg) 487 { 488 const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap; 489 struct rpcbind_args *map = msg->rpc_argp; 490 unsigned short port = ntohs(sin6->sin6_port); 491 int result; 492 493 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 494 495 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 496 "local rpcbind\n", (port ? "" : "un"), 497 map->r_prog, map->r_vers, 498 map->r_addr, map->r_netid); 499 500 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 501 if (port) 502 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 503 504 result = rpcb_register_call(sn->rpcb_local_clnt4, msg); 505 kfree(map->r_addr); 506 return result; 507 } 508 509 static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn, 510 struct rpc_message *msg) 511 { 512 struct rpcbind_args *map = msg->rpc_argp; 513 514 dprintk("RPC: unregistering [%u, %u, '%s'] with " 515 "local rpcbind\n", 516 map->r_prog, map->r_vers, map->r_netid); 517 518 map->r_addr = ""; 519 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 520 521 return rpcb_register_call(sn->rpcb_local_clnt4, msg); 522 } 523 524 /** 525 * rpcb_v4_register - set or unset a port registration with the local rpcbind 526 * @net: target network namespace 527 * @program: RPC program number of service to (un)register 528 * @version: RPC version number of service to (un)register 529 * @address: address family, IP address, and port to (un)register 530 * @netid: netid of transport protocol to (un)register 531 * 532 * Returns zero if the registration request was dispatched successfully 533 * and the rpcbind daemon returned success. Otherwise, returns an errno 534 * value that reflects the nature of the error (request could not be 535 * dispatched, timed out, or rpcbind returned an error). 536 * 537 * RPC services invoke this function to advertise their contact 538 * information via the system's rpcbind daemon. RPC services 539 * invoke this function once for each [program, version, address, 540 * netid] tuple they wish to advertise. 541 * 542 * Callers may also unregister RPC services that are registered at a 543 * specific address by setting the port number in @address to zero. 544 * They may unregister all registered protocol families at once for 545 * a service by passing a NULL @address argument. If @netid is "" 546 * then all netids for [program, version, address] are unregistered. 547 * 548 * This function uses rpcbind protocol version 4 to contact the 549 * local rpcbind daemon. The local rpcbind daemon must support 550 * version 4 of the rpcbind protocol in order for these functions 551 * to register a service successfully. 552 * 553 * Supported netids include "udp" and "tcp" for UDP and TCP over 554 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6, 555 * respectively. 556 * 557 * The contents of @address determine the address family and the 558 * port to be registered. The usual practice is to pass INADDR_ANY 559 * as the raw address, but specifying a non-zero address is also 560 * supported by this API if the caller wishes to advertise an RPC 561 * service on a specific network interface. 562 * 563 * Note that passing in INADDR_ANY does not create the same service 564 * registration as IN6ADDR_ANY. The former advertises an RPC 565 * service on any IPv4 address, but not on IPv6. The latter 566 * advertises the service on all IPv4 and IPv6 addresses. 567 */ 568 int rpcb_v4_register(struct net *net, const u32 program, const u32 version, 569 const struct sockaddr *address, const char *netid) 570 { 571 struct rpcbind_args map = { 572 .r_prog = program, 573 .r_vers = version, 574 .r_netid = netid, 575 .r_owner = RPCB_OWNER_STRING, 576 }; 577 struct rpc_message msg = { 578 .rpc_argp = &map, 579 }; 580 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 581 582 if (sn->rpcb_local_clnt4 == NULL) 583 return -EPROTONOSUPPORT; 584 585 if (address == NULL) 586 return rpcb_unregister_all_protofamilies(sn, &msg); 587 588 switch (address->sa_family) { 589 case AF_INET: 590 return rpcb_register_inet4(sn, address, &msg); 591 case AF_INET6: 592 return rpcb_register_inet6(sn, address, &msg); 593 } 594 595 return -EAFNOSUPPORT; 596 } 597 598 static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, 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 *xprt = rcu_dereference(clnt->cl_xprt); 627 628 while (parent != clnt) { 629 if (rcu_dereference(parent->cl_xprt) != xprt) 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 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 do { 662 clnt = rpcb_find_transport_owner(task->tk_client); 663 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 664 } while (xprt == NULL); 665 rcu_read_unlock(); 666 667 dprintk("RPC: %5u %s(%s, %u, %u, %d)\n", 668 task->tk_pid, __func__, 669 xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot); 670 671 /* Put self on the wait queue to ensure we get notified if 672 * some other task is already attempting to bind the port */ 673 rpc_sleep_on(&xprt->binding, task, NULL); 674 675 if (xprt_test_and_set_binding(xprt)) { 676 dprintk("RPC: %5u %s: waiting for another binder\n", 677 task->tk_pid, __func__); 678 xprt_put(xprt); 679 return; 680 } 681 682 /* Someone else may have bound if we slept */ 683 if (xprt_bound(xprt)) { 684 status = 0; 685 dprintk("RPC: %5u %s: already bound\n", 686 task->tk_pid, __func__); 687 goto bailout_nofree; 688 } 689 690 /* Parent transport's destination address */ 691 salen = rpc_peeraddr(clnt, sap, sizeof(addr)); 692 693 /* Don't ever use rpcbind v2 for AF_INET6 requests */ 694 switch (sap->sa_family) { 695 case AF_INET: 696 proc = rpcb_next_version[xprt->bind_index].rpc_proc; 697 bind_version = rpcb_next_version[xprt->bind_index].rpc_vers; 698 break; 699 case AF_INET6: 700 proc = rpcb_next_version6[xprt->bind_index].rpc_proc; 701 bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers; 702 break; 703 default: 704 status = -EAFNOSUPPORT; 705 dprintk("RPC: %5u %s: bad address family\n", 706 task->tk_pid, __func__); 707 goto bailout_nofree; 708 } 709 if (proc == NULL) { 710 xprt->bind_index = 0; 711 status = -EPFNOSUPPORT; 712 dprintk("RPC: %5u %s: no more getport versions available\n", 713 task->tk_pid, __func__); 714 goto bailout_nofree; 715 } 716 717 dprintk("RPC: %5u %s: trying rpcbind version %u\n", 718 task->tk_pid, __func__, bind_version); 719 720 rpcb_clnt = rpcb_create(xprt->xprt_net, xprt->servername, sap, salen, 721 xprt->prot, bind_version); 722 if (IS_ERR(rpcb_clnt)) { 723 status = PTR_ERR(rpcb_clnt); 724 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n", 725 task->tk_pid, __func__, PTR_ERR(rpcb_clnt)); 726 goto bailout_nofree; 727 } 728 729 map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC); 730 if (!map) { 731 status = -ENOMEM; 732 dprintk("RPC: %5u %s: no memory available\n", 733 task->tk_pid, __func__); 734 goto bailout_release_client; 735 } 736 map->r_prog = clnt->cl_prog; 737 map->r_vers = clnt->cl_vers; 738 map->r_prot = xprt->prot; 739 map->r_port = 0; 740 map->r_xprt = xprt; 741 map->r_status = -EIO; 742 743 switch (bind_version) { 744 case RPCBVERS_4: 745 case RPCBVERS_3: 746 map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; 747 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC); 748 map->r_owner = ""; 749 break; 750 case RPCBVERS_2: 751 map->r_addr = NULL; 752 break; 753 default: 754 BUG(); 755 } 756 757 child = rpcb_call_async(rpcb_clnt, map, proc); 758 rpc_release_client(rpcb_clnt); 759 if (IS_ERR(child)) { 760 /* rpcb_map_release() has freed the arguments */ 761 dprintk("RPC: %5u %s: rpc_run_task failed\n", 762 task->tk_pid, __func__); 763 return; 764 } 765 766 xprt->stat.bind_count++; 767 rpc_put_task(child); 768 return; 769 770 bailout_release_client: 771 rpc_release_client(rpcb_clnt); 772 bailout_nofree: 773 rpcb_wake_rpcbind_waiters(xprt, status); 774 task->tk_status = status; 775 xprt_put(xprt); 776 } 777 EXPORT_SYMBOL_GPL(rpcb_getport_async); 778 779 /* 780 * Rpcbind child task calls this callback via tk_exit. 781 */ 782 static void rpcb_getport_done(struct rpc_task *child, void *data) 783 { 784 struct rpcbind_args *map = data; 785 struct rpc_xprt *xprt = map->r_xprt; 786 int status = child->tk_status; 787 788 /* Garbage reply: retry with a lesser rpcbind version */ 789 if (status == -EIO) 790 status = -EPROTONOSUPPORT; 791 792 /* rpcbind server doesn't support this rpcbind protocol version */ 793 if (status == -EPROTONOSUPPORT) 794 xprt->bind_index++; 795 796 if (status < 0) { 797 /* rpcbind server not available on remote host? */ 798 xprt->ops->set_port(xprt, 0); 799 } else if (map->r_port == 0) { 800 /* Requested RPC service wasn't registered on remote host */ 801 xprt->ops->set_port(xprt, 0); 802 status = -EACCES; 803 } else { 804 /* Succeeded */ 805 xprt->ops->set_port(xprt, map->r_port); 806 xprt_set_bound(xprt); 807 status = 0; 808 } 809 810 dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n", 811 child->tk_pid, status, map->r_port); 812 813 map->r_status = status; 814 } 815 816 /* 817 * XDR functions for rpcbind 818 */ 819 820 static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, 821 const struct rpcbind_args *rpcb) 822 { 823 __be32 *p; 824 825 dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n", 826 req->rq_task->tk_pid, 827 req->rq_task->tk_msg.rpc_proc->p_name, 828 rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port); 829 830 p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2); 831 *p++ = cpu_to_be32(rpcb->r_prog); 832 *p++ = cpu_to_be32(rpcb->r_vers); 833 *p++ = cpu_to_be32(rpcb->r_prot); 834 *p = cpu_to_be32(rpcb->r_port); 835 } 836 837 static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr, 838 struct rpcbind_args *rpcb) 839 { 840 unsigned long port; 841 __be32 *p; 842 843 rpcb->r_port = 0; 844 845 p = xdr_inline_decode(xdr, 4); 846 if (unlikely(p == NULL)) 847 return -EIO; 848 849 port = be32_to_cpup(p); 850 dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid, 851 req->rq_task->tk_msg.rpc_proc->p_name, port); 852 if (unlikely(port > USHRT_MAX)) 853 return -EIO; 854 855 rpcb->r_port = port; 856 return 0; 857 } 858 859 static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr, 860 unsigned int *boolp) 861 { 862 __be32 *p; 863 864 p = xdr_inline_decode(xdr, 4); 865 if (unlikely(p == NULL)) 866 return -EIO; 867 868 *boolp = 0; 869 if (*p != xdr_zero) 870 *boolp = 1; 871 872 dprintk("RPC: %5u RPCB_%s call %s\n", 873 req->rq_task->tk_pid, 874 req->rq_task->tk_msg.rpc_proc->p_name, 875 (*boolp ? "succeeded" : "failed")); 876 return 0; 877 } 878 879 static void encode_rpcb_string(struct xdr_stream *xdr, const char *string, 880 const u32 maxstrlen) 881 { 882 __be32 *p; 883 u32 len; 884 885 len = strlen(string); 886 WARN_ON_ONCE(len > maxstrlen); 887 if (len > maxstrlen) 888 /* truncate and hope for the best */ 889 len = maxstrlen; 890 p = xdr_reserve_space(xdr, 4 + len); 891 xdr_encode_opaque(p, string, len); 892 } 893 894 static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 895 const struct rpcbind_args *rpcb) 896 { 897 __be32 *p; 898 899 dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n", 900 req->rq_task->tk_pid, 901 req->rq_task->tk_msg.rpc_proc->p_name, 902 rpcb->r_prog, rpcb->r_vers, 903 rpcb->r_netid, rpcb->r_addr); 904 905 p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2); 906 *p++ = cpu_to_be32(rpcb->r_prog); 907 *p = cpu_to_be32(rpcb->r_vers); 908 909 encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN); 910 encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN); 911 encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN); 912 } 913 914 static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 915 struct rpcbind_args *rpcb) 916 { 917 struct sockaddr_storage address; 918 struct sockaddr *sap = (struct sockaddr *)&address; 919 __be32 *p; 920 u32 len; 921 922 rpcb->r_port = 0; 923 924 p = xdr_inline_decode(xdr, 4); 925 if (unlikely(p == NULL)) 926 goto out_fail; 927 len = be32_to_cpup(p); 928 929 /* 930 * If the returned universal address is a null string, 931 * the requested RPC service was not registered. 932 */ 933 if (len == 0) { 934 dprintk("RPC: %5u RPCB reply: program not registered\n", 935 req->rq_task->tk_pid); 936 return 0; 937 } 938 939 if (unlikely(len > RPCBIND_MAXUADDRLEN)) 940 goto out_fail; 941 942 p = xdr_inline_decode(xdr, len); 943 if (unlikely(p == NULL)) 944 goto out_fail; 945 dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid, 946 req->rq_task->tk_msg.rpc_proc->p_name, (char *)p); 947 948 if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len, 949 sap, sizeof(address)) == 0) 950 goto out_fail; 951 rpcb->r_port = rpc_get_port(sap); 952 953 return 0; 954 955 out_fail: 956 dprintk("RPC: %5u malformed RPCB_%s reply\n", 957 req->rq_task->tk_pid, 958 req->rq_task->tk_msg.rpc_proc->p_name); 959 return -EIO; 960 } 961 962 /* 963 * Not all rpcbind procedures described in RFC 1833 are implemented 964 * since the Linux kernel RPC code requires only these. 965 */ 966 967 static struct rpc_procinfo rpcb_procedures2[] = { 968 [RPCBPROC_SET] = { 969 .p_proc = RPCBPROC_SET, 970 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 971 .p_decode = (kxdrdproc_t)rpcb_dec_set, 972 .p_arglen = RPCB_mappingargs_sz, 973 .p_replen = RPCB_setres_sz, 974 .p_statidx = RPCBPROC_SET, 975 .p_timer = 0, 976 .p_name = "SET", 977 }, 978 [RPCBPROC_UNSET] = { 979 .p_proc = RPCBPROC_UNSET, 980 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 981 .p_decode = (kxdrdproc_t)rpcb_dec_set, 982 .p_arglen = RPCB_mappingargs_sz, 983 .p_replen = RPCB_setres_sz, 984 .p_statidx = RPCBPROC_UNSET, 985 .p_timer = 0, 986 .p_name = "UNSET", 987 }, 988 [RPCBPROC_GETPORT] = { 989 .p_proc = RPCBPROC_GETPORT, 990 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 991 .p_decode = (kxdrdproc_t)rpcb_dec_getport, 992 .p_arglen = RPCB_mappingargs_sz, 993 .p_replen = RPCB_getportres_sz, 994 .p_statidx = RPCBPROC_GETPORT, 995 .p_timer = 0, 996 .p_name = "GETPORT", 997 }, 998 }; 999 1000 static struct rpc_procinfo rpcb_procedures3[] = { 1001 [RPCBPROC_SET] = { 1002 .p_proc = RPCBPROC_SET, 1003 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1004 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1005 .p_arglen = RPCB_getaddrargs_sz, 1006 .p_replen = RPCB_setres_sz, 1007 .p_statidx = RPCBPROC_SET, 1008 .p_timer = 0, 1009 .p_name = "SET", 1010 }, 1011 [RPCBPROC_UNSET] = { 1012 .p_proc = RPCBPROC_UNSET, 1013 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1014 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1015 .p_arglen = RPCB_getaddrargs_sz, 1016 .p_replen = RPCB_setres_sz, 1017 .p_statidx = RPCBPROC_UNSET, 1018 .p_timer = 0, 1019 .p_name = "UNSET", 1020 }, 1021 [RPCBPROC_GETADDR] = { 1022 .p_proc = RPCBPROC_GETADDR, 1023 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1024 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1025 .p_arglen = RPCB_getaddrargs_sz, 1026 .p_replen = RPCB_getaddrres_sz, 1027 .p_statidx = RPCBPROC_GETADDR, 1028 .p_timer = 0, 1029 .p_name = "GETADDR", 1030 }, 1031 }; 1032 1033 static struct rpc_procinfo rpcb_procedures4[] = { 1034 [RPCBPROC_SET] = { 1035 .p_proc = RPCBPROC_SET, 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_SET, 1041 .p_timer = 0, 1042 .p_name = "SET", 1043 }, 1044 [RPCBPROC_UNSET] = { 1045 .p_proc = RPCBPROC_UNSET, 1046 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1047 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1048 .p_arglen = RPCB_getaddrargs_sz, 1049 .p_replen = RPCB_setres_sz, 1050 .p_statidx = RPCBPROC_UNSET, 1051 .p_timer = 0, 1052 .p_name = "UNSET", 1053 }, 1054 [RPCBPROC_GETADDR] = { 1055 .p_proc = RPCBPROC_GETADDR, 1056 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1057 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1058 .p_arglen = RPCB_getaddrargs_sz, 1059 .p_replen = RPCB_getaddrres_sz, 1060 .p_statidx = RPCBPROC_GETADDR, 1061 .p_timer = 0, 1062 .p_name = "GETADDR", 1063 }, 1064 }; 1065 1066 static const struct rpcb_info rpcb_next_version[] = { 1067 { 1068 .rpc_vers = RPCBVERS_2, 1069 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT], 1070 }, 1071 { 1072 .rpc_proc = NULL, 1073 }, 1074 }; 1075 1076 static const struct rpcb_info rpcb_next_version6[] = { 1077 { 1078 .rpc_vers = RPCBVERS_4, 1079 .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR], 1080 }, 1081 { 1082 .rpc_vers = RPCBVERS_3, 1083 .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR], 1084 }, 1085 { 1086 .rpc_proc = NULL, 1087 }, 1088 }; 1089 1090 static const struct rpc_version rpcb_version2 = { 1091 .number = RPCBVERS_2, 1092 .nrprocs = ARRAY_SIZE(rpcb_procedures2), 1093 .procs = rpcb_procedures2 1094 }; 1095 1096 static const struct rpc_version rpcb_version3 = { 1097 .number = RPCBVERS_3, 1098 .nrprocs = ARRAY_SIZE(rpcb_procedures3), 1099 .procs = rpcb_procedures3 1100 }; 1101 1102 static const struct rpc_version rpcb_version4 = { 1103 .number = RPCBVERS_4, 1104 .nrprocs = ARRAY_SIZE(rpcb_procedures4), 1105 .procs = rpcb_procedures4 1106 }; 1107 1108 static const struct rpc_version *rpcb_version[] = { 1109 NULL, 1110 NULL, 1111 &rpcb_version2, 1112 &rpcb_version3, 1113 &rpcb_version4 1114 }; 1115 1116 static struct rpc_stat rpcb_stats; 1117 1118 static const struct rpc_program rpcb_program = { 1119 .name = "rpcbind", 1120 .number = RPCBIND_PROGRAM, 1121 .nrvers = ARRAY_SIZE(rpcb_version), 1122 .version = rpcb_version, 1123 .stats = &rpcb_stats, 1124 }; 1125