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 48 enum { 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 112 113 static void rpcb_getport_done(struct rpc_task *, void *); 114 static void rpcb_map_release(void *data); 115 static const struct rpc_program rpcb_program; 116 117 struct 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 }; 130 131 static struct rpc_procinfo rpcb_procedures2[]; 132 static struct rpc_procinfo rpcb_procedures3[]; 133 static struct rpc_procinfo rpcb_procedures4[]; 134 135 struct rpcb_info { 136 u32 rpc_vers; 137 struct rpc_procinfo * rpc_proc; 138 }; 139 140 static const struct rpcb_info rpcb_next_version[]; 141 static const struct rpcb_info rpcb_next_version6[]; 142 143 static const struct rpc_call_ops rpcb_getport_ops = { 144 .rpc_call_done = rpcb_getport_done, 145 .rpc_release = rpcb_map_release, 146 }; 147 148 static 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 } 153 154 static 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 } 163 164 static 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 } 177 178 void 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 } 205 206 static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt, 207 struct rpc_clnt *clnt4) 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 smp_wmb(); 215 sn->rpcb_users = 1; 216 dprintk("RPC: created new rpcb local clients (rpcb_local_clnt: " 217 "%p, rpcb_local_clnt4: %p) for net %p%s\n", 218 sn->rpcb_local_clnt, sn->rpcb_local_clnt4, 219 net, (net == &init_net) ? " (init_net)" : ""); 220 } 221 222 /* 223 * Returns zero on success, otherwise a negative errno value 224 * is returned. 225 */ 226 static int rpcb_create_local_unix(struct net *net) 227 { 228 static const struct sockaddr_un rpcb_localaddr_rpcbind = { 229 .sun_family = AF_LOCAL, 230 .sun_path = RPCBIND_SOCK_PATHNAME, 231 }; 232 struct rpc_create_args args = { 233 .net = net, 234 .protocol = XPRT_TRANSPORT_LOCAL, 235 .address = (struct sockaddr *)&rpcb_localaddr_rpcbind, 236 .addrsize = sizeof(rpcb_localaddr_rpcbind), 237 .servername = "localhost", 238 .program = &rpcb_program, 239 .version = RPCBVERS_2, 240 .authflavor = RPC_AUTH_NULL, 241 }; 242 struct rpc_clnt *clnt, *clnt4; 243 int result = 0; 244 245 /* 246 * Because we requested an RPC PING at transport creation time, 247 * this works only if the user space portmapper is rpcbind, and 248 * it's listening on AF_LOCAL on the named socket. 249 */ 250 clnt = rpc_create(&args); 251 if (IS_ERR(clnt)) { 252 dprintk("RPC: failed to create AF_LOCAL rpcbind " 253 "client (errno %ld).\n", PTR_ERR(clnt)); 254 result = PTR_ERR(clnt); 255 goto out; 256 } 257 258 clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); 259 if (IS_ERR(clnt4)) { 260 dprintk("RPC: failed to bind second program to " 261 "rpcbind v4 client (errno %ld).\n", 262 PTR_ERR(clnt4)); 263 clnt4 = NULL; 264 } 265 266 rpcb_set_local(net, clnt, clnt4); 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 .flags = RPC_CLNT_CREATE_NOPING, 293 }; 294 struct rpc_clnt *clnt, *clnt4; 295 int result = 0; 296 297 clnt = rpc_create(&args); 298 if (IS_ERR(clnt)) { 299 dprintk("RPC: failed to create local rpcbind " 300 "client (errno %ld).\n", PTR_ERR(clnt)); 301 result = PTR_ERR(clnt); 302 goto out; 303 } 304 305 /* 306 * This results in an RPC ping. On systems running portmapper, 307 * the v4 ping will fail. Proceed anyway, but disallow rpcb 308 * v4 upcalls. 309 */ 310 clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); 311 if (IS_ERR(clnt4)) { 312 dprintk("RPC: failed to bind second program to " 313 "rpcbind v4 client (errno %ld).\n", 314 PTR_ERR(clnt4)); 315 clnt4 = NULL; 316 } 317 318 rpcb_set_local(net, clnt, clnt4); 319 320 out: 321 return result; 322 } 323 324 /* 325 * Returns zero on success, otherwise a negative errno value 326 * is returned. 327 */ 328 int rpcb_create_local(struct net *net) 329 { 330 static DEFINE_MUTEX(rpcb_create_local_mutex); 331 int result = 0; 332 333 if (rpcb_get_local(net)) 334 return result; 335 336 mutex_lock(&rpcb_create_local_mutex); 337 if (rpcb_get_local(net)) 338 goto out; 339 340 if (rpcb_create_local_unix(net) != 0) 341 result = rpcb_create_local_net(net); 342 343 out: 344 mutex_unlock(&rpcb_create_local_mutex); 345 return result; 346 } 347 348 static struct rpc_clnt *rpcb_create(struct net *net, const char *hostname, 349 struct sockaddr *srvaddr, size_t salen, 350 int proto, u32 version) 351 { 352 struct rpc_create_args args = { 353 .net = net, 354 .protocol = proto, 355 .address = srvaddr, 356 .addrsize = salen, 357 .servername = hostname, 358 .program = &rpcb_program, 359 .version = version, 360 .authflavor = RPC_AUTH_UNIX, 361 .flags = (RPC_CLNT_CREATE_NOPING | 362 RPC_CLNT_CREATE_NONPRIVPORT), 363 }; 364 365 switch (srvaddr->sa_family) { 366 case AF_INET: 367 ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT); 368 break; 369 case AF_INET6: 370 ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT); 371 break; 372 default: 373 return ERR_PTR(-EAFNOSUPPORT); 374 } 375 376 return rpc_create(&args); 377 } 378 379 static int rpcb_register_call(struct rpc_clnt *clnt, struct rpc_message *msg) 380 { 381 int result, error = 0; 382 383 msg->rpc_resp = &result; 384 385 error = rpc_call_sync(clnt, msg, RPC_TASK_SOFTCONN); 386 if (error < 0) { 387 dprintk("RPC: failed to contact local rpcbind " 388 "server (errno %d).\n", -error); 389 return error; 390 } 391 392 if (!result) 393 return -EACCES; 394 return 0; 395 } 396 397 /** 398 * rpcb_register - set or unset a port registration with the local rpcbind svc 399 * @net: target network namespace 400 * @prog: RPC program number to bind 401 * @vers: RPC version number to bind 402 * @prot: transport protocol to register 403 * @port: port value to register 404 * 405 * Returns zero if the registration request was dispatched successfully 406 * and the rpcbind daemon returned success. Otherwise, returns an errno 407 * value that reflects the nature of the error (request could not be 408 * dispatched, timed out, or rpcbind returned an error). 409 * 410 * RPC services invoke this function to advertise their contact 411 * information via the system's rpcbind daemon. RPC services 412 * invoke this function once for each [program, version, transport] 413 * tuple they wish to advertise. 414 * 415 * Callers may also unregister RPC services that are no longer 416 * available by setting the passed-in port to zero. This removes 417 * all registered transports for [program, version] from the local 418 * rpcbind database. 419 * 420 * This function uses rpcbind protocol version 2 to contact the 421 * local rpcbind daemon. 422 * 423 * Registration works over both AF_INET and AF_INET6, and services 424 * registered via this function are advertised as available for any 425 * address. If the local rpcbind daemon is listening on AF_INET6, 426 * services registered via this function will be advertised on 427 * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6 428 * addresses). 429 */ 430 int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port) 431 { 432 struct rpcbind_args map = { 433 .r_prog = prog, 434 .r_vers = vers, 435 .r_prot = prot, 436 .r_port = port, 437 }; 438 struct rpc_message msg = { 439 .rpc_argp = &map, 440 }; 441 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 442 443 dprintk("RPC: %sregistering (%u, %u, %d, %u) with local " 444 "rpcbind\n", (port ? "" : "un"), 445 prog, vers, prot, port); 446 447 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET]; 448 if (port) 449 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET]; 450 451 return rpcb_register_call(sn->rpcb_local_clnt, &msg); 452 } 453 454 /* 455 * Fill in AF_INET family-specific arguments to register 456 */ 457 static int rpcb_register_inet4(struct sunrpc_net *sn, 458 const struct sockaddr *sap, 459 struct rpc_message *msg) 460 { 461 const struct sockaddr_in *sin = (const struct sockaddr_in *)sap; 462 struct rpcbind_args *map = msg->rpc_argp; 463 unsigned short port = ntohs(sin->sin_port); 464 int result; 465 466 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 467 468 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 469 "local rpcbind\n", (port ? "" : "un"), 470 map->r_prog, map->r_vers, 471 map->r_addr, map->r_netid); 472 473 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 474 if (port) 475 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 476 477 result = rpcb_register_call(sn->rpcb_local_clnt4, msg); 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 int result; 493 494 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); 495 496 dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with " 497 "local rpcbind\n", (port ? "" : "un"), 498 map->r_prog, map->r_vers, 499 map->r_addr, map->r_netid); 500 501 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 502 if (port) 503 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; 504 505 result = rpcb_register_call(sn->rpcb_local_clnt4, msg); 506 kfree(map->r_addr); 507 return result; 508 } 509 510 static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn, 511 struct rpc_message *msg) 512 { 513 struct rpcbind_args *map = msg->rpc_argp; 514 515 dprintk("RPC: unregistering [%u, %u, '%s'] with " 516 "local rpcbind\n", 517 map->r_prog, map->r_vers, map->r_netid); 518 519 map->r_addr = ""; 520 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; 521 522 return rpcb_register_call(sn->rpcb_local_clnt4, msg); 523 } 524 525 /** 526 * rpcb_v4_register - set or unset a port registration with the local rpcbind 527 * @net: target network namespace 528 * @program: RPC program number of service to (un)register 529 * @version: RPC version number of service to (un)register 530 * @address: address family, IP address, and port to (un)register 531 * @netid: netid of transport protocol to (un)register 532 * 533 * Returns zero if the registration request was dispatched successfully 534 * and the rpcbind daemon returned success. Otherwise, returns an errno 535 * value that reflects the nature of the error (request could not be 536 * dispatched, timed out, or rpcbind returned an error). 537 * 538 * RPC services invoke this function to advertise their contact 539 * information via the system's rpcbind daemon. RPC services 540 * invoke this function once for each [program, version, address, 541 * netid] tuple they wish to advertise. 542 * 543 * Callers may also unregister RPC services that are registered at a 544 * specific address by setting the port number in @address to zero. 545 * They may unregister all registered protocol families at once for 546 * a service by passing a NULL @address argument. If @netid is "" 547 * then all netids for [program, version, address] are unregistered. 548 * 549 * This function uses rpcbind protocol version 4 to contact the 550 * local rpcbind daemon. The local rpcbind daemon must support 551 * version 4 of the rpcbind protocol in order for these functions 552 * to register a service successfully. 553 * 554 * Supported netids include "udp" and "tcp" for UDP and TCP over 555 * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6, 556 * respectively. 557 * 558 * The contents of @address determine the address family and the 559 * port to be registered. The usual practice is to pass INADDR_ANY 560 * as the raw address, but specifying a non-zero address is also 561 * supported by this API if the caller wishes to advertise an RPC 562 * service on a specific network interface. 563 * 564 * Note that passing in INADDR_ANY does not create the same service 565 * registration as IN6ADDR_ANY. The former advertises an RPC 566 * service on any IPv4 address, but not on IPv6. The latter 567 * advertises the service on all IPv4 and IPv6 addresses. 568 */ 569 int rpcb_v4_register(struct net *net, const u32 program, const u32 version, 570 const struct sockaddr *address, const char *netid) 571 { 572 struct rpcbind_args map = { 573 .r_prog = program, 574 .r_vers = version, 575 .r_netid = netid, 576 .r_owner = RPCB_OWNER_STRING, 577 }; 578 struct rpc_message msg = { 579 .rpc_argp = &map, 580 }; 581 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 582 583 if (sn->rpcb_local_clnt4 == NULL) 584 return -EPROTONOSUPPORT; 585 586 if (address == NULL) 587 return rpcb_unregister_all_protofamilies(sn, &msg); 588 589 switch (address->sa_family) { 590 case AF_INET: 591 return rpcb_register_inet4(sn, address, &msg); 592 case AF_INET6: 593 return rpcb_register_inet6(sn, address, &msg); 594 } 595 596 return -EAFNOSUPPORT; 597 } 598 599 static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc) 600 { 601 struct rpc_message msg = { 602 .rpc_proc = proc, 603 .rpc_argp = map, 604 .rpc_resp = map, 605 }; 606 struct rpc_task_setup task_setup_data = { 607 .rpc_client = rpcb_clnt, 608 .rpc_message = &msg, 609 .callback_ops = &rpcb_getport_ops, 610 .callback_data = map, 611 .flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN, 612 }; 613 614 return rpc_run_task(&task_setup_data); 615 } 616 617 /* 618 * In the case where rpc clients have been cloned, we want to make 619 * sure that we use the program number/version etc of the actual 620 * owner of the xprt. To do so, we walk back up the tree of parents 621 * to find whoever created the transport and/or whoever has the 622 * autobind flag set. 623 */ 624 static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt) 625 { 626 struct rpc_clnt *parent = clnt->cl_parent; 627 struct rpc_xprt *xprt = rcu_dereference(clnt->cl_xprt); 628 629 while (parent != clnt) { 630 if (rcu_dereference(parent->cl_xprt) != xprt) 631 break; 632 if (clnt->cl_autobind) 633 break; 634 clnt = parent; 635 parent = parent->cl_parent; 636 } 637 return clnt; 638 } 639 640 /** 641 * rpcb_getport_async - obtain the port for a given RPC service on a given host 642 * @task: task that is waiting for portmapper request 643 * 644 * This one can be called for an ongoing RPC request, and can be used in 645 * an async (rpciod) context. 646 */ 647 void rpcb_getport_async(struct rpc_task *task) 648 { 649 struct rpc_clnt *clnt; 650 struct rpc_procinfo *proc; 651 u32 bind_version; 652 struct rpc_xprt *xprt; 653 struct rpc_clnt *rpcb_clnt; 654 struct rpcbind_args *map; 655 struct rpc_task *child; 656 struct sockaddr_storage addr; 657 struct sockaddr *sap = (struct sockaddr *)&addr; 658 size_t salen; 659 int status; 660 661 rcu_read_lock(); 662 do { 663 clnt = rpcb_find_transport_owner(task->tk_client); 664 xprt = xprt_get(rcu_dereference(clnt->cl_xprt)); 665 } while (xprt == NULL); 666 rcu_read_unlock(); 667 668 dprintk("RPC: %5u %s(%s, %u, %u, %d)\n", 669 task->tk_pid, __func__, 670 xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot); 671 672 /* Put self on the wait queue to ensure we get notified if 673 * some other task is already attempting to bind the port */ 674 rpc_sleep_on(&xprt->binding, task, NULL); 675 676 if (xprt_test_and_set_binding(xprt)) { 677 dprintk("RPC: %5u %s: waiting for another binder\n", 678 task->tk_pid, __func__); 679 xprt_put(xprt); 680 return; 681 } 682 683 /* Someone else may have bound if we slept */ 684 if (xprt_bound(xprt)) { 685 status = 0; 686 dprintk("RPC: %5u %s: already bound\n", 687 task->tk_pid, __func__); 688 goto bailout_nofree; 689 } 690 691 /* Parent transport's destination address */ 692 salen = rpc_peeraddr(clnt, sap, sizeof(addr)); 693 694 /* Don't ever use rpcbind v2 for AF_INET6 requests */ 695 switch (sap->sa_family) { 696 case AF_INET: 697 proc = rpcb_next_version[xprt->bind_index].rpc_proc; 698 bind_version = rpcb_next_version[xprt->bind_index].rpc_vers; 699 break; 700 case AF_INET6: 701 proc = rpcb_next_version6[xprt->bind_index].rpc_proc; 702 bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers; 703 break; 704 default: 705 status = -EAFNOSUPPORT; 706 dprintk("RPC: %5u %s: bad address family\n", 707 task->tk_pid, __func__); 708 goto bailout_nofree; 709 } 710 if (proc == NULL) { 711 xprt->bind_index = 0; 712 status = -EPFNOSUPPORT; 713 dprintk("RPC: %5u %s: no more getport versions available\n", 714 task->tk_pid, __func__); 715 goto bailout_nofree; 716 } 717 718 dprintk("RPC: %5u %s: trying rpcbind version %u\n", 719 task->tk_pid, __func__, bind_version); 720 721 rpcb_clnt = rpcb_create(xprt->xprt_net, xprt->servername, sap, salen, 722 xprt->prot, bind_version); 723 if (IS_ERR(rpcb_clnt)) { 724 status = PTR_ERR(rpcb_clnt); 725 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n", 726 task->tk_pid, __func__, PTR_ERR(rpcb_clnt)); 727 goto bailout_nofree; 728 } 729 730 map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC); 731 if (!map) { 732 status = -ENOMEM; 733 dprintk("RPC: %5u %s: no memory available\n", 734 task->tk_pid, __func__); 735 goto bailout_release_client; 736 } 737 map->r_prog = clnt->cl_prog; 738 map->r_vers = clnt->cl_vers; 739 map->r_prot = xprt->prot; 740 map->r_port = 0; 741 map->r_xprt = xprt; 742 map->r_status = -EIO; 743 744 switch (bind_version) { 745 case RPCBVERS_4: 746 case RPCBVERS_3: 747 map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; 748 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC); 749 map->r_owner = ""; 750 break; 751 case RPCBVERS_2: 752 map->r_addr = NULL; 753 break; 754 default: 755 BUG(); 756 } 757 758 child = rpcb_call_async(rpcb_clnt, map, proc); 759 rpc_release_client(rpcb_clnt); 760 if (IS_ERR(child)) { 761 /* rpcb_map_release() has freed the arguments */ 762 dprintk("RPC: %5u %s: rpc_run_task failed\n", 763 task->tk_pid, __func__); 764 return; 765 } 766 767 xprt->stat.bind_count++; 768 rpc_put_task(child); 769 return; 770 771 bailout_release_client: 772 rpc_release_client(rpcb_clnt); 773 bailout_nofree: 774 rpcb_wake_rpcbind_waiters(xprt, status); 775 task->tk_status = status; 776 xprt_put(xprt); 777 } 778 EXPORT_SYMBOL_GPL(rpcb_getport_async); 779 780 /* 781 * Rpcbind child task calls this callback via tk_exit. 782 */ 783 static void rpcb_getport_done(struct rpc_task *child, void *data) 784 { 785 struct rpcbind_args *map = data; 786 struct rpc_xprt *xprt = map->r_xprt; 787 int status = child->tk_status; 788 789 /* Garbage reply: retry with a lesser rpcbind version */ 790 if (status == -EIO) 791 status = -EPROTONOSUPPORT; 792 793 /* rpcbind server doesn't support this rpcbind protocol version */ 794 if (status == -EPROTONOSUPPORT) 795 xprt->bind_index++; 796 797 if (status < 0) { 798 /* rpcbind server not available on remote host? */ 799 xprt->ops->set_port(xprt, 0); 800 } else if (map->r_port == 0) { 801 /* Requested RPC service wasn't registered on remote host */ 802 xprt->ops->set_port(xprt, 0); 803 status = -EACCES; 804 } else { 805 /* Succeeded */ 806 xprt->ops->set_port(xprt, map->r_port); 807 xprt_set_bound(xprt); 808 status = 0; 809 } 810 811 dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n", 812 child->tk_pid, status, map->r_port); 813 814 map->r_status = status; 815 } 816 817 /* 818 * XDR functions for rpcbind 819 */ 820 821 static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, 822 const struct rpcbind_args *rpcb) 823 { 824 __be32 *p; 825 826 dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n", 827 req->rq_task->tk_pid, 828 req->rq_task->tk_msg.rpc_proc->p_name, 829 rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port); 830 831 p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2); 832 *p++ = cpu_to_be32(rpcb->r_prog); 833 *p++ = cpu_to_be32(rpcb->r_vers); 834 *p++ = cpu_to_be32(rpcb->r_prot); 835 *p = cpu_to_be32(rpcb->r_port); 836 } 837 838 static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr, 839 struct rpcbind_args *rpcb) 840 { 841 unsigned long port; 842 __be32 *p; 843 844 rpcb->r_port = 0; 845 846 p = xdr_inline_decode(xdr, 4); 847 if (unlikely(p == NULL)) 848 return -EIO; 849 850 port = be32_to_cpup(p); 851 dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid, 852 req->rq_task->tk_msg.rpc_proc->p_name, port); 853 if (unlikely(port > USHRT_MAX)) 854 return -EIO; 855 856 rpcb->r_port = port; 857 return 0; 858 } 859 860 static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr, 861 unsigned int *boolp) 862 { 863 __be32 *p; 864 865 p = xdr_inline_decode(xdr, 4); 866 if (unlikely(p == NULL)) 867 return -EIO; 868 869 *boolp = 0; 870 if (*p != xdr_zero) 871 *boolp = 1; 872 873 dprintk("RPC: %5u RPCB_%s call %s\n", 874 req->rq_task->tk_pid, 875 req->rq_task->tk_msg.rpc_proc->p_name, 876 (*boolp ? "succeeded" : "failed")); 877 return 0; 878 } 879 880 static void encode_rpcb_string(struct xdr_stream *xdr, const char *string, 881 const u32 maxstrlen) 882 { 883 __be32 *p; 884 u32 len; 885 886 len = strlen(string); 887 WARN_ON_ONCE(len > maxstrlen); 888 if (len > maxstrlen) 889 /* truncate and hope for the best */ 890 len = maxstrlen; 891 p = xdr_reserve_space(xdr, 4 + len); 892 xdr_encode_opaque(p, string, len); 893 } 894 895 static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 896 const struct rpcbind_args *rpcb) 897 { 898 __be32 *p; 899 900 dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n", 901 req->rq_task->tk_pid, 902 req->rq_task->tk_msg.rpc_proc->p_name, 903 rpcb->r_prog, rpcb->r_vers, 904 rpcb->r_netid, rpcb->r_addr); 905 906 p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2); 907 *p++ = cpu_to_be32(rpcb->r_prog); 908 *p = cpu_to_be32(rpcb->r_vers); 909 910 encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN); 911 encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN); 912 encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN); 913 } 914 915 static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, 916 struct rpcbind_args *rpcb) 917 { 918 struct sockaddr_storage address; 919 struct sockaddr *sap = (struct sockaddr *)&address; 920 __be32 *p; 921 u32 len; 922 923 rpcb->r_port = 0; 924 925 p = xdr_inline_decode(xdr, 4); 926 if (unlikely(p == NULL)) 927 goto out_fail; 928 len = be32_to_cpup(p); 929 930 /* 931 * If the returned universal address is a null string, 932 * the requested RPC service was not registered. 933 */ 934 if (len == 0) { 935 dprintk("RPC: %5u RPCB reply: program not registered\n", 936 req->rq_task->tk_pid); 937 return 0; 938 } 939 940 if (unlikely(len > RPCBIND_MAXUADDRLEN)) 941 goto out_fail; 942 943 p = xdr_inline_decode(xdr, len); 944 if (unlikely(p == NULL)) 945 goto out_fail; 946 dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid, 947 req->rq_task->tk_msg.rpc_proc->p_name, (char *)p); 948 949 if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len, 950 sap, sizeof(address)) == 0) 951 goto out_fail; 952 rpcb->r_port = rpc_get_port(sap); 953 954 return 0; 955 956 out_fail: 957 dprintk("RPC: %5u malformed RPCB_%s reply\n", 958 req->rq_task->tk_pid, 959 req->rq_task->tk_msg.rpc_proc->p_name); 960 return -EIO; 961 } 962 963 /* 964 * Not all rpcbind procedures described in RFC 1833 are implemented 965 * since the Linux kernel RPC code requires only these. 966 */ 967 968 static struct rpc_procinfo rpcb_procedures2[] = { 969 [RPCBPROC_SET] = { 970 .p_proc = RPCBPROC_SET, 971 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 972 .p_decode = (kxdrdproc_t)rpcb_dec_set, 973 .p_arglen = RPCB_mappingargs_sz, 974 .p_replen = RPCB_setres_sz, 975 .p_statidx = RPCBPROC_SET, 976 .p_timer = 0, 977 .p_name = "SET", 978 }, 979 [RPCBPROC_UNSET] = { 980 .p_proc = RPCBPROC_UNSET, 981 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 982 .p_decode = (kxdrdproc_t)rpcb_dec_set, 983 .p_arglen = RPCB_mappingargs_sz, 984 .p_replen = RPCB_setres_sz, 985 .p_statidx = RPCBPROC_UNSET, 986 .p_timer = 0, 987 .p_name = "UNSET", 988 }, 989 [RPCBPROC_GETPORT] = { 990 .p_proc = RPCBPROC_GETPORT, 991 .p_encode = (kxdreproc_t)rpcb_enc_mapping, 992 .p_decode = (kxdrdproc_t)rpcb_dec_getport, 993 .p_arglen = RPCB_mappingargs_sz, 994 .p_replen = RPCB_getportres_sz, 995 .p_statidx = RPCBPROC_GETPORT, 996 .p_timer = 0, 997 .p_name = "GETPORT", 998 }, 999 }; 1000 1001 static struct rpc_procinfo rpcb_procedures3[] = { 1002 [RPCBPROC_SET] = { 1003 .p_proc = RPCBPROC_SET, 1004 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1005 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1006 .p_arglen = RPCB_getaddrargs_sz, 1007 .p_replen = RPCB_setres_sz, 1008 .p_statidx = RPCBPROC_SET, 1009 .p_timer = 0, 1010 .p_name = "SET", 1011 }, 1012 [RPCBPROC_UNSET] = { 1013 .p_proc = RPCBPROC_UNSET, 1014 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1015 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1016 .p_arglen = RPCB_getaddrargs_sz, 1017 .p_replen = RPCB_setres_sz, 1018 .p_statidx = RPCBPROC_UNSET, 1019 .p_timer = 0, 1020 .p_name = "UNSET", 1021 }, 1022 [RPCBPROC_GETADDR] = { 1023 .p_proc = RPCBPROC_GETADDR, 1024 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1025 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1026 .p_arglen = RPCB_getaddrargs_sz, 1027 .p_replen = RPCB_getaddrres_sz, 1028 .p_statidx = RPCBPROC_GETADDR, 1029 .p_timer = 0, 1030 .p_name = "GETADDR", 1031 }, 1032 }; 1033 1034 static struct rpc_procinfo rpcb_procedures4[] = { 1035 [RPCBPROC_SET] = { 1036 .p_proc = RPCBPROC_SET, 1037 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1038 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1039 .p_arglen = RPCB_getaddrargs_sz, 1040 .p_replen = RPCB_setres_sz, 1041 .p_statidx = RPCBPROC_SET, 1042 .p_timer = 0, 1043 .p_name = "SET", 1044 }, 1045 [RPCBPROC_UNSET] = { 1046 .p_proc = RPCBPROC_UNSET, 1047 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1048 .p_decode = (kxdrdproc_t)rpcb_dec_set, 1049 .p_arglen = RPCB_getaddrargs_sz, 1050 .p_replen = RPCB_setres_sz, 1051 .p_statidx = RPCBPROC_UNSET, 1052 .p_timer = 0, 1053 .p_name = "UNSET", 1054 }, 1055 [RPCBPROC_GETADDR] = { 1056 .p_proc = RPCBPROC_GETADDR, 1057 .p_encode = (kxdreproc_t)rpcb_enc_getaddr, 1058 .p_decode = (kxdrdproc_t)rpcb_dec_getaddr, 1059 .p_arglen = RPCB_getaddrargs_sz, 1060 .p_replen = RPCB_getaddrres_sz, 1061 .p_statidx = RPCBPROC_GETADDR, 1062 .p_timer = 0, 1063 .p_name = "GETADDR", 1064 }, 1065 }; 1066 1067 static const struct rpcb_info rpcb_next_version[] = { 1068 { 1069 .rpc_vers = RPCBVERS_2, 1070 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT], 1071 }, 1072 { 1073 .rpc_proc = NULL, 1074 }, 1075 }; 1076 1077 static const struct rpcb_info rpcb_next_version6[] = { 1078 { 1079 .rpc_vers = RPCBVERS_4, 1080 .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR], 1081 }, 1082 { 1083 .rpc_vers = RPCBVERS_3, 1084 .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR], 1085 }, 1086 { 1087 .rpc_proc = NULL, 1088 }, 1089 }; 1090 1091 static const struct rpc_version rpcb_version2 = { 1092 .number = RPCBVERS_2, 1093 .nrprocs = ARRAY_SIZE(rpcb_procedures2), 1094 .procs = rpcb_procedures2 1095 }; 1096 1097 static const struct rpc_version rpcb_version3 = { 1098 .number = RPCBVERS_3, 1099 .nrprocs = ARRAY_SIZE(rpcb_procedures3), 1100 .procs = rpcb_procedures3 1101 }; 1102 1103 static const struct rpc_version rpcb_version4 = { 1104 .number = RPCBVERS_4, 1105 .nrprocs = ARRAY_SIZE(rpcb_procedures4), 1106 .procs = rpcb_procedures4 1107 }; 1108 1109 static const struct rpc_version *rpcb_version[] = { 1110 NULL, 1111 NULL, 1112 &rpcb_version2, 1113 &rpcb_version3, 1114 &rpcb_version4 1115 }; 1116 1117 static struct rpc_stat rpcb_stats; 1118 1119 static const struct rpc_program rpcb_program = { 1120 .name = "rpcbind", 1121 .number = RPCBIND_PROGRAM, 1122 .nrvers = ARRAY_SIZE(rpcb_version), 1123 .version = rpcb_version, 1124 .stats = &rpcb_stats, 1125 }; 1126