net/sunrpc/rpcb

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This source file includes following definitions.
rpcb_wake_rpcbind_waiters
rpcb_map_release
rpcb_get_local
rpcb_put_local
rpcb_set_local
rpcb_create_local_unix
rpcb_create_local_net
rpcb_create_local
rpcb_create
rpcb_register_call
rpcb_register
rpcb_register_inet4
rpcb_register_inet6
rpcb_unregister_all_protofamilies
rpcb_v4_register
rpcb_call_async
rpcb_find_transport_owner
rpcb_getport_async
rpcb_getport_done
rpcb_enc_mapping
rpcb_dec_getport
rpcb_dec_set
encode_rpcb_string
rpcb_enc_getaddr
rpcb_dec_getaddr
   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 "netns.h"
  35 
  36 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
  37 # define RPCDBG_FACILITY        RPCDBG_BIND
  38 #endif
  39 
  40 #define RPCBIND_SOCK_PATHNAME   "/var/run/rpcbind.sock"
  41 
  42 #define RPCBIND_PROGRAM         (100000u)
  43 #define RPCBIND_PORT            (111u)
  44 
  45 #define RPCBVERS_2              (2u)
  46 #define RPCBVERS_3              (3u)
  47 #define RPCBVERS_4              (4u)
  48 
  49 enum {
  50         RPCBPROC_NULL,
  51         RPCBPROC_SET,
  52         RPCBPROC_UNSET,
  53         RPCBPROC_GETPORT,
  54         RPCBPROC_GETADDR = 3,           /* alias for GETPORT */
  55         RPCBPROC_DUMP,
  56         RPCBPROC_CALLIT,
  57         RPCBPROC_BCAST = 5,             /* alias for CALLIT */
  58         RPCBPROC_GETTIME,
  59         RPCBPROC_UADDR2TADDR,
  60         RPCBPROC_TADDR2UADDR,
  61         RPCBPROC_GETVERSADDR,
  62         RPCBPROC_INDIRECT,
  63         RPCBPROC_GETADDRLIST,
  64         RPCBPROC_GETSTAT,
  65 };
  66 
  67 /*
  68  * r_owner
  69  *
  70  * The "owner" is allowed to unset a service in the rpcbind database.
  71  *
  72  * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a
  73  * UID which it maps to a local user name via a password lookup.
  74  * In all other cases it is ignored.
  75  *
  76  * For SET/UNSET requests, user space provides a value, even for
  77  * network requests, and GETADDR uses an empty string.  We follow
  78  * those precedents here.
  79  */
  80 #define RPCB_OWNER_STRING       "0"
  81 #define RPCB_MAXOWNERLEN        sizeof(RPCB_OWNER_STRING)
  82 
  83 /*
  84  * XDR data type sizes
  85  */
  86 #define RPCB_program_sz         (1)
  87 #define RPCB_version_sz         (1)
  88 #define RPCB_protocol_sz        (1)
  89 #define RPCB_port_sz            (1)
  90 #define RPCB_boolean_sz         (1)
  91 
  92 #define RPCB_netid_sz           (1 + XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
  93 #define RPCB_addr_sz            (1 + XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
  94 #define RPCB_ownerstring_sz     (1 + XDR_QUADLEN(RPCB_MAXOWNERLEN))
  95 
  96 /*
  97  * XDR argument and result sizes
  98  */
  99 #define RPCB_mappingargs_sz     (RPCB_program_sz + RPCB_version_sz + \
 100                                 RPCB_protocol_sz + RPCB_port_sz)
 101 #define RPCB_getaddrargs_sz     (RPCB_program_sz + RPCB_version_sz + \
 102                                 RPCB_netid_sz + RPCB_addr_sz + \
 103                                 RPCB_ownerstring_sz)
 104 
 105 #define RPCB_getportres_sz      RPCB_port_sz
 106 #define RPCB_setres_sz          RPCB_boolean_sz
 107 
 108 /*
 109  * Note that RFC 1833 does not put any size restrictions on the
 110  * address string returned by the remote rpcbind database.
 111  */
 112 #define RPCB_getaddrres_sz      RPCB_addr_sz
 113 
 114 static void                     rpcb_getport_done(struct rpc_task *, void *);
 115 static void                     rpcb_map_release(void *data);
 116 static const struct rpc_program rpcb_program;
 117 
 118 struct rpcbind_args {
 119         struct rpc_xprt *       r_xprt;
 120 
 121         u32                     r_prog;
 122         u32                     r_vers;
 123         u32                     r_prot;
 124         unsigned short          r_port;
 125         const char *            r_netid;
 126         const char *            r_addr;
 127         const char *            r_owner;
 128 
 129         int                     r_status;
 130 };
 131 
 132 static const struct rpc_procinfo rpcb_procedures2[];
 133 static const struct rpc_procinfo rpcb_procedures3[];
 134 static const struct rpc_procinfo rpcb_procedures4[];
 135 
 136 struct rpcb_info {
 137         u32                     rpc_vers;
 138         const struct rpc_procinfo *rpc_proc;
 139 };
 140 
 141 static const struct rpcb_info rpcb_next_version[];
 142 static const struct rpcb_info rpcb_next_version6[];
 143 
 144 static const struct rpc_call_ops rpcb_getport_ops = {
 145         .rpc_call_done          = rpcb_getport_done,
 146         .rpc_release            = rpcb_map_release,
 147 };
 148 
 149 static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
 150 {
 151         xprt_clear_binding(xprt);
 152         rpc_wake_up_status(&xprt->binding, status);
 153 }
 154 
 155 static void rpcb_map_release(void *data)
 156 {
 157         struct rpcbind_args *map = data;
 158 
 159         rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
 160         xprt_put(map->r_xprt);
 161         kfree(map->r_addr);
 162         kfree(map);
 163 }
 164 
 165 static int rpcb_get_local(struct net *net)
 166 {
 167         int cnt;
 168         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 169 
 170         spin_lock(&sn->rpcb_clnt_lock);
 171         if (sn->rpcb_users)
 172                 sn->rpcb_users++;
 173         cnt = sn->rpcb_users;
 174         spin_unlock(&sn->rpcb_clnt_lock);
 175 
 176         return cnt;
 177 }
 178 
 179 void rpcb_put_local(struct net *net)
 180 {
 181         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 182         struct rpc_clnt *clnt = sn->rpcb_local_clnt;
 183         struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4;
 184         int shutdown = 0;
 185 
 186         spin_lock(&sn->rpcb_clnt_lock);
 187         if (sn->rpcb_users) {
 188                 if (--sn->rpcb_users == 0) {
 189                         sn->rpcb_local_clnt = NULL;
 190                         sn->rpcb_local_clnt4 = NULL;
 191                 }
 192                 shutdown = !sn->rpcb_users;
 193         }
 194         spin_unlock(&sn->rpcb_clnt_lock);
 195 
 196         if (shutdown) {
 197                 /*
 198                  * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
 199                  */
 200                 if (clnt4)
 201                         rpc_shutdown_client(clnt4);
 202                 if (clnt)
 203                         rpc_shutdown_client(clnt);
 204         }
 205 }
 206 
 207 static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt,
 208                         struct rpc_clnt *clnt4,
 209                         bool is_af_local)
 210 {
 211         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 212 
 213         /* Protected by rpcb_create_local_mutex */
 214         sn->rpcb_local_clnt = clnt;
 215         sn->rpcb_local_clnt4 = clnt4;
 216         sn->rpcb_is_af_local = is_af_local ? 1 : 0;
 217         smp_wmb();
 218         sn->rpcb_users = 1;
 219         dprintk("RPC:       created new rpcb local clients (rpcb_local_clnt: "
 220                 "%p, rpcb_local_clnt4: %p) for net %x%s\n",
 221                 sn->rpcb_local_clnt, sn->rpcb_local_clnt4,
 222                 net->ns.inum, (net == &init_net) ? " (init_net)" : "");
 223 }
 224 
 225 /*
 226  * Returns zero on success, otherwise a negative errno value
 227  * is returned.
 228  */
 229 static int rpcb_create_local_unix(struct net *net)
 230 {
 231         static const struct sockaddr_un rpcb_localaddr_rpcbind = {
 232                 .sun_family             = AF_LOCAL,
 233                 .sun_path               = RPCBIND_SOCK_PATHNAME,
 234         };
 235         struct rpc_create_args args = {
 236                 .net            = net,
 237                 .protocol       = XPRT_TRANSPORT_LOCAL,
 238                 .address        = (struct sockaddr *)&rpcb_localaddr_rpcbind,
 239                 .addrsize       = sizeof(rpcb_localaddr_rpcbind),
 240                 .servername     = "localhost",
 241                 .program        = &rpcb_program,
 242                 .version        = RPCBVERS_2,
 243                 .authflavor     = RPC_AUTH_NULL,
 244                 .cred           = current_cred(),
 245                 /*
 246                  * We turn off the idle timeout to prevent the kernel
 247                  * from automatically disconnecting the socket.
 248                  * Otherwise, we'd have to cache the mount namespace
 249                  * of the caller and somehow pass that to the socket
 250                  * reconnect code.
 251                  */
 252                 .flags          = RPC_CLNT_CREATE_NO_IDLE_TIMEOUT,
 253         };
 254         struct rpc_clnt *clnt, *clnt4;
 255         int result = 0;
 256 
 257         /*
 258          * Because we requested an RPC PING at transport creation time,
 259          * this works only if the user space portmapper is rpcbind, and
 260          * it's listening on AF_LOCAL on the named socket.
 261          */
 262         clnt = rpc_create(&args);
 263         if (IS_ERR(clnt)) {
 264                 dprintk("RPC:       failed to create AF_LOCAL rpcbind "
 265                                 "client (errno %ld).\n", PTR_ERR(clnt));
 266                 result = PTR_ERR(clnt);
 267                 goto out;
 268         }
 269 
 270         clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 271         if (IS_ERR(clnt4)) {
 272                 dprintk("RPC:       failed to bind second program to "
 273                                 "rpcbind v4 client (errno %ld).\n",
 274                                 PTR_ERR(clnt4));
 275                 clnt4 = NULL;
 276         }
 277 
 278         rpcb_set_local(net, clnt, clnt4, true);
 279 
 280 out:
 281         return result;
 282 }
 283 
 284 /*
 285  * Returns zero on success, otherwise a negative errno value
 286  * is returned.
 287  */
 288 static int rpcb_create_local_net(struct net *net)
 289 {
 290         static const struct sockaddr_in rpcb_inaddr_loopback = {
 291                 .sin_family             = AF_INET,
 292                 .sin_addr.s_addr        = htonl(INADDR_LOOPBACK),
 293                 .sin_port               = htons(RPCBIND_PORT),
 294         };
 295         struct rpc_create_args args = {
 296                 .net            = net,
 297                 .protocol       = XPRT_TRANSPORT_TCP,
 298                 .address        = (struct sockaddr *)&rpcb_inaddr_loopback,
 299                 .addrsize       = sizeof(rpcb_inaddr_loopback),
 300                 .servername     = "localhost",
 301                 .program        = &rpcb_program,
 302                 .version        = RPCBVERS_2,
 303                 .authflavor     = RPC_AUTH_UNIX,
 304                 .cred           = current_cred(),
 305                 .flags          = RPC_CLNT_CREATE_NOPING,
 306         };
 307         struct rpc_clnt *clnt, *clnt4;
 308         int result = 0;
 309 
 310         clnt = rpc_create(&args);
 311         if (IS_ERR(clnt)) {
 312                 dprintk("RPC:       failed to create local rpcbind "
 313                                 "client (errno %ld).\n", PTR_ERR(clnt));
 314                 result = PTR_ERR(clnt);
 315                 goto out;
 316         }
 317 
 318         /*
 319          * This results in an RPC ping.  On systems running portmapper,
 320          * the v4 ping will fail.  Proceed anyway, but disallow rpcb
 321          * v4 upcalls.
 322          */
 323         clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
 324         if (IS_ERR(clnt4)) {
 325                 dprintk("RPC:       failed to bind second program to "
 326                                 "rpcbind v4 client (errno %ld).\n",
 327                                 PTR_ERR(clnt4));
 328                 clnt4 = NULL;
 329         }
 330 
 331         rpcb_set_local(net, clnt, clnt4, false);
 332 
 333 out:
 334         return result;
 335 }
 336 
 337 /*
 338  * Returns zero on success, otherwise a negative errno value
 339  * is returned.
 340  */
 341 int rpcb_create_local(struct net *net)
 342 {
 343         static DEFINE_MUTEX(rpcb_create_local_mutex);
 344         int result = 0;
 345 
 346         if (rpcb_get_local(net))
 347                 return result;
 348 
 349         mutex_lock(&rpcb_create_local_mutex);
 350         if (rpcb_get_local(net))
 351                 goto out;
 352 
 353         if (rpcb_create_local_unix(net) != 0)
 354                 result = rpcb_create_local_net(net);
 355 
 356 out:
 357         mutex_unlock(&rpcb_create_local_mutex);
 358         return result;
 359 }
 360 
 361 static struct rpc_clnt *rpcb_create(struct net *net, const char *nodename,
 362                                     const char *hostname,
 363                                     struct sockaddr *srvaddr, size_t salen,
 364                                     int proto, u32 version,
 365                                     const struct cred *cred)
 366 {
 367         struct rpc_create_args args = {
 368                 .net            = net,
 369                 .protocol       = proto,
 370                 .address        = srvaddr,
 371                 .addrsize       = salen,
 372                 .servername     = hostname,
 373                 .nodename       = nodename,
 374                 .program        = &rpcb_program,
 375                 .version        = version,
 376                 .authflavor     = RPC_AUTH_UNIX,
 377                 .cred           = cred,
 378                 .flags          = (RPC_CLNT_CREATE_NOPING |
 379                                         RPC_CLNT_CREATE_NONPRIVPORT),
 380         };
 381 
 382         switch (srvaddr->sa_family) {
 383         case AF_INET:
 384                 ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
 385                 break;
 386         case AF_INET6:
 387                 ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
 388                 break;
 389         default:
 390                 return ERR_PTR(-EAFNOSUPPORT);
 391         }
 392 
 393         return rpc_create(&args);
 394 }
 395 
 396 static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set)
 397 {
 398         int flags = RPC_TASK_NOCONNECT;
 399         int error, result = 0;
 400 
 401         if (is_set || !sn->rpcb_is_af_local)
 402                 flags = RPC_TASK_SOFTCONN;
 403         msg->rpc_resp = &result;
 404 
 405         error = rpc_call_sync(clnt, msg, flags);
 406         if (error < 0) {
 407                 dprintk("RPC:       failed to contact local rpcbind "
 408                                 "server (errno %d).\n", -error);
 409                 return error;
 410         }
 411 
 412         if (!result)
 413                 return -EACCES;
 414         return 0;
 415 }
 416 
 417 /**
 418  * rpcb_register - set or unset a port registration with the local rpcbind svc
 419  * @net: target network namespace
 420  * @prog: RPC program number to bind
 421  * @vers: RPC version number to bind
 422  * @prot: transport protocol to register
 423  * @port: port value to register
 424  *
 425  * Returns zero if the registration request was dispatched successfully
 426  * and the rpcbind daemon returned success.  Otherwise, returns an errno
 427  * value that reflects the nature of the error (request could not be
 428  * dispatched, timed out, or rpcbind returned an error).
 429  *
 430  * RPC services invoke this function to advertise their contact
 431  * information via the system's rpcbind daemon.  RPC services
 432  * invoke this function once for each [program, version, transport]
 433  * tuple they wish to advertise.
 434  *
 435  * Callers may also unregister RPC services that are no longer
 436  * available by setting the passed-in port to zero.  This removes
 437  * all registered transports for [program, version] from the local
 438  * rpcbind database.
 439  *
 440  * This function uses rpcbind protocol version 2 to contact the
 441  * local rpcbind daemon.
 442  *
 443  * Registration works over both AF_INET and AF_INET6, and services
 444  * registered via this function are advertised as available for any
 445  * address.  If the local rpcbind daemon is listening on AF_INET6,
 446  * services registered via this function will be advertised on
 447  * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
 448  * addresses).
 449  */
 450 int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port)
 451 {
 452         struct rpcbind_args map = {
 453                 .r_prog         = prog,
 454                 .r_vers         = vers,
 455                 .r_prot         = prot,
 456                 .r_port         = port,
 457         };
 458         struct rpc_message msg = {
 459                 .rpc_argp       = &map,
 460         };
 461         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 462         bool is_set = false;
 463 
 464         dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
 465                         "rpcbind\n", (port ? "" : "un"),
 466                         prog, vers, prot, port);
 467 
 468         msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
 469         if (port != 0) {
 470                 msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];
 471                 is_set = true;
 472         }
 473 
 474         return rpcb_register_call(sn, sn->rpcb_local_clnt, &msg, is_set);
 475 }
 476 
 477 /*
 478  * Fill in AF_INET family-specific arguments to register
 479  */
 480 static int rpcb_register_inet4(struct sunrpc_net *sn,
 481                                const struct sockaddr *sap,
 482                                struct rpc_message *msg)
 483 {
 484         const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
 485         struct rpcbind_args *map = msg->rpc_argp;
 486         unsigned short port = ntohs(sin->sin_port);
 487         bool is_set = false;
 488         int result;
 489 
 490         map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 491 
 492         dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
 493                 "local rpcbind\n", (port ? "" : "un"),
 494                         map->r_prog, map->r_vers,
 495                         map->r_addr, map->r_netid);
 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 /*
 509  * Fill in AF_INET6 family-specific arguments to register
 510  */
 511 static int rpcb_register_inet6(struct sunrpc_net *sn,
 512                                const struct sockaddr *sap,
 513                                struct rpc_message *msg)
 514 {
 515         const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
 516         struct rpcbind_args *map = msg->rpc_argp;
 517         unsigned short port = ntohs(sin6->sin6_port);
 518         bool is_set = false;
 519         int result;
 520 
 521         map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
 522 
 523         dprintk("RPC:       %sregistering [%u, %u, %s, '%s'] with "
 524                 "local rpcbind\n", (port ? "" : "un"),
 525                         map->r_prog, map->r_vers,
 526                         map->r_addr, map->r_netid);
 527 
 528         msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 529         if (port != 0) {
 530                 msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
 531                 is_set = true;
 532         }
 533 
 534         result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
 535         kfree(map->r_addr);
 536         return result;
 537 }
 538 
 539 static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn,
 540                                              struct rpc_message *msg)
 541 {
 542         struct rpcbind_args *map = msg->rpc_argp;
 543 
 544         dprintk("RPC:       unregistering [%u, %u, '%s'] with "
 545                 "local rpcbind\n",
 546                         map->r_prog, map->r_vers, map->r_netid);
 547 
 548         map->r_addr = "";
 549         msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
 550 
 551         return rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, false);
 552 }
 553 
 554 /**
 555  * rpcb_v4_register - set or unset a port registration with the local rpcbind
 556  * @net: target network namespace
 557  * @program: RPC program number of service to (un)register
 558  * @version: RPC version number of service to (un)register
 559  * @address: address family, IP address, and port to (un)register
 560  * @netid: netid of transport protocol to (un)register
 561  *
 562  * Returns zero if the registration request was dispatched successfully
 563  * and the rpcbind daemon returned success.  Otherwise, returns an errno
 564  * value that reflects the nature of the error (request could not be
 565  * dispatched, timed out, or rpcbind returned an error).
 566  *
 567  * RPC services invoke this function to advertise their contact
 568  * information via the system's rpcbind daemon.  RPC services
 569  * invoke this function once for each [program, version, address,
 570  * netid] tuple they wish to advertise.
 571  *
 572  * Callers may also unregister RPC services that are registered at a
 573  * specific address by setting the port number in @address to zero.
 574  * They may unregister all registered protocol families at once for
 575  * a service by passing a NULL @address argument.  If @netid is ""
 576  * then all netids for [program, version, address] are unregistered.
 577  *
 578  * This function uses rpcbind protocol version 4 to contact the
 579  * local rpcbind daemon.  The local rpcbind daemon must support
 580  * version 4 of the rpcbind protocol in order for these functions
 581  * to register a service successfully.
 582  *
 583  * Supported netids include "udp" and "tcp" for UDP and TCP over
 584  * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
 585  * respectively.
 586  *
 587  * The contents of @address determine the address family and the
 588  * port to be registered.  The usual practice is to pass INADDR_ANY
 589  * as the raw address, but specifying a non-zero address is also
 590  * supported by this API if the caller wishes to advertise an RPC
 591  * service on a specific network interface.
 592  *
 593  * Note that passing in INADDR_ANY does not create the same service
 594  * registration as IN6ADDR_ANY.  The former advertises an RPC
 595  * service on any IPv4 address, but not on IPv6.  The latter
 596  * advertises the service on all IPv4 and IPv6 addresses.
 597  */
 598 int rpcb_v4_register(struct net *net, const u32 program, const u32 version,
 599                      const struct sockaddr *address, const char *netid)
 600 {
 601         struct rpcbind_args map = {
 602                 .r_prog         = program,
 603                 .r_vers         = version,
 604                 .r_netid        = netid,
 605                 .r_owner        = RPCB_OWNER_STRING,
 606         };
 607         struct rpc_message msg = {
 608                 .rpc_argp       = &map,
 609         };
 610         struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
 611 
 612         if (sn->rpcb_local_clnt4 == NULL)
 613                 return -EPROTONOSUPPORT;
 614 
 615         if (address == NULL)
 616                 return rpcb_unregister_all_protofamilies(sn, &msg);
 617 
 618         switch (address->sa_family) {
 619         case AF_INET:
 620                 return rpcb_register_inet4(sn, address, &msg);
 621         case AF_INET6:
 622                 return rpcb_register_inet6(sn, address, &msg);
 623         }
 624 
 625         return -EAFNOSUPPORT;
 626 }
 627 
 628 static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt,
 629                 struct rpcbind_args *map, const struct rpc_procinfo *proc)
 630 {
 631         struct rpc_message msg = {
 632                 .rpc_proc = proc,
 633                 .rpc_argp = map,
 634                 .rpc_resp = map,
 635         };
 636         struct rpc_task_setup task_setup_data = {
 637                 .rpc_client = rpcb_clnt,
 638                 .rpc_message = &msg,
 639                 .callback_ops = &rpcb_getport_ops,
 640                 .callback_data = map,
 641                 .flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN,
 642         };
 643 
 644         return rpc_run_task(&task_setup_data);
 645 }
 646 
 647 /*
 648  * In the case where rpc clients have been cloned, we want to make
 649  * sure that we use the program number/version etc of the actual
 650  * owner of the xprt. To do so, we walk back up the tree of parents
 651  * to find whoever created the transport and/or whoever has the
 652  * autobind flag set.
 653  */
 654 static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
 655 {
 656         struct rpc_clnt *parent = clnt->cl_parent;
 657         struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch);
 658 
 659         while (parent != clnt) {
 660                 if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps)
 661                         break;
 662                 if (clnt->cl_autobind)
 663                         break;
 664                 clnt = parent;
 665                 parent = parent->cl_parent;
 666         }
 667         return clnt;
 668 }
 669 
 670 /**
 671  * rpcb_getport_async - obtain the port for a given RPC service on a given host
 672  * @task: task that is waiting for portmapper request
 673  *
 674  * This one can be called for an ongoing RPC request, and can be used in
 675  * an async (rpciod) context.
 676  */
 677 void rpcb_getport_async(struct rpc_task *task)
 678 {
 679         struct rpc_clnt *clnt;
 680         const struct rpc_procinfo *proc;
 681         u32 bind_version;
 682         struct rpc_xprt *xprt;
 683         struct rpc_clnt *rpcb_clnt;
 684         struct rpcbind_args *map;
 685         struct rpc_task *child;
 686         struct sockaddr_storage addr;
 687         struct sockaddr *sap = (struct sockaddr *)&addr;
 688         size_t salen;
 689         int status;
 690 
 691         rcu_read_lock();
 692         clnt = rpcb_find_transport_owner(task->tk_client);
 693         rcu_read_unlock();
 694         xprt = xprt_get(task->tk_xprt);
 695 
 696         dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
 697                 task->tk_pid, __func__,
 698                 xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot);
 699 
 700         /* Put self on the wait queue to ensure we get notified if
 701          * some other task is already attempting to bind the port */
 702         rpc_sleep_on_timeout(&xprt->binding, task,
 703                         NULL, jiffies + xprt->bind_timeout);
 704 
 705         if (xprt_test_and_set_binding(xprt)) {
 706                 dprintk("RPC: %5u %s: waiting for another binder\n",
 707                         task->tk_pid, __func__);
 708                 xprt_put(xprt);
 709                 return;
 710         }
 711 
 712         /* Someone else may have bound if we slept */
 713         if (xprt_bound(xprt)) {
 714                 status = 0;
 715                 dprintk("RPC: %5u %s: already bound\n",
 716                         task->tk_pid, __func__);
 717                 goto bailout_nofree;
 718         }
 719 
 720         /* Parent transport's destination address */
 721         salen = rpc_peeraddr(clnt, sap, sizeof(addr));
 722 
 723         /* Don't ever use rpcbind v2 for AF_INET6 requests */
 724         switch (sap->sa_family) {
 725         case AF_INET:
 726                 proc = rpcb_next_version[xprt->bind_index].rpc_proc;
 727                 bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
 728                 break;
 729         case AF_INET6:
 730                 proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
 731                 bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
 732                 break;
 733         default:
 734                 status = -EAFNOSUPPORT;
 735                 dprintk("RPC: %5u %s: bad address family\n",
 736                                 task->tk_pid, __func__);
 737                 goto bailout_nofree;
 738         }
 739         if (proc == NULL) {
 740                 xprt->bind_index = 0;
 741                 status = -EPFNOSUPPORT;
 742                 dprintk("RPC: %5u %s: no more getport versions available\n",
 743                         task->tk_pid, __func__);
 744                 goto bailout_nofree;
 745         }
 746 
 747         dprintk("RPC: %5u %s: trying rpcbind version %u\n",
 748                 task->tk_pid, __func__, bind_version);
 749 
 750         rpcb_clnt = rpcb_create(xprt->xprt_net,
 751                                 clnt->cl_nodename,
 752                                 xprt->servername, sap, salen,
 753                                 xprt->prot, bind_version,
 754                                 clnt->cl_cred);
 755         if (IS_ERR(rpcb_clnt)) {
 756                 status = PTR_ERR(rpcb_clnt);
 757                 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
 758                         task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
 759                 goto bailout_nofree;
 760         }
 761 
 762         map = kzalloc(sizeof(struct rpcbind_args), GFP_NOFS);
 763         if (!map) {
 764                 status = -ENOMEM;
 765                 dprintk("RPC: %5u %s: no memory available\n",
 766                         task->tk_pid, __func__);
 767                 goto bailout_release_client;
 768         }
 769         map->r_prog = clnt->cl_prog;
 770         map->r_vers = clnt->cl_vers;
 771         map->r_prot = xprt->prot;
 772         map->r_port = 0;
 773         map->r_xprt = xprt;
 774         map->r_status = -EIO;
 775 
 776         switch (bind_version) {
 777         case RPCBVERS_4:
 778         case RPCBVERS_3:
 779                 map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID];
 780                 map->r_addr = rpc_sockaddr2uaddr(sap, GFP_NOFS);
 781                 if (!map->r_addr) {
 782                         status = -ENOMEM;
 783                         dprintk("RPC: %5u %s: no memory available\n",
 784                                 task->tk_pid, __func__);
 785                         goto bailout_free_args;
 786                 }
 787                 map->r_owner = "";
 788                 break;
 789         case RPCBVERS_2:
 790                 map->r_addr = NULL;
 791                 break;
 792         default:
 793                 BUG();
 794         }
 795 
 796         child = rpcb_call_async(rpcb_clnt, map, proc);
 797         rpc_release_client(rpcb_clnt);
 798         if (IS_ERR(child)) {
 799                 /* rpcb_map_release() has freed the arguments */
 800                 dprintk("RPC: %5u %s: rpc_run_task failed\n",
 801                         task->tk_pid, __func__);
 802                 return;
 803         }
 804 
 805         xprt->stat.bind_count++;
 806         rpc_put_task(child);
 807         return;
 808 
 809 bailout_free_args:
 810         kfree(map);
 811 bailout_release_client:
 812         rpc_release_client(rpcb_clnt);
 813 bailout_nofree:
 814         rpcb_wake_rpcbind_waiters(xprt, status);
 815         task->tk_status = status;
 816         xprt_put(xprt);
 817 }
 818 EXPORT_SYMBOL_GPL(rpcb_getport_async);
 819 
 820 /*
 821  * Rpcbind child task calls this callback via tk_exit.
 822  */
 823 static void rpcb_getport_done(struct rpc_task *child, void *data)
 824 {
 825         struct rpcbind_args *map = data;
 826         struct rpc_xprt *xprt = map->r_xprt;
 827         int status = child->tk_status;
 828 
 829         /* Garbage reply: retry with a lesser rpcbind version */
 830         if (status == -EIO)
 831                 status = -EPROTONOSUPPORT;
 832 
 833         /* rpcbind server doesn't support this rpcbind protocol version */
 834         if (status == -EPROTONOSUPPORT)
 835                 xprt->bind_index++;
 836 
 837         if (status < 0) {
 838                 /* rpcbind server not available on remote host? */
 839                 xprt->ops->set_port(xprt, 0);
 840         } else if (map->r_port == 0) {
 841                 /* Requested RPC service wasn't registered on remote host */
 842                 xprt->ops->set_port(xprt, 0);
 843                 status = -EACCES;
 844         } else {
 845                 /* Succeeded */
 846                 xprt->ops->set_port(xprt, map->r_port);
 847                 xprt_set_bound(xprt);
 848                 status = 0;
 849         }
 850 
 851         dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
 852                         child->tk_pid, status, map->r_port);
 853 
 854         map->r_status = status;
 855 }
 856 
 857 /*
 858  * XDR functions for rpcbind
 859  */
 860 
 861 static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr,
 862                              const void *data)
 863 {
 864         const struct rpcbind_args *rpcb = data;
 865         __be32 *p;
 866 
 867         dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n",
 868                         req->rq_task->tk_pid,
 869                         req->rq_task->tk_msg.rpc_proc->p_name,
 870                         rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
 871 
 872         p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2);
 873         *p++ = cpu_to_be32(rpcb->r_prog);
 874         *p++ = cpu_to_be32(rpcb->r_vers);
 875         *p++ = cpu_to_be32(rpcb->r_prot);
 876         *p   = cpu_to_be32(rpcb->r_port);
 877 }
 878 
 879 static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr,
 880                             void *data)
 881 {
 882         struct rpcbind_args *rpcb = data;
 883         unsigned long port;
 884         __be32 *p;
 885 
 886         rpcb->r_port = 0;
 887 
 888         p = xdr_inline_decode(xdr, 4);
 889         if (unlikely(p == NULL))
 890                 return -EIO;
 891 
 892         port = be32_to_cpup(p);
 893         dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid,
 894                         req->rq_task->tk_msg.rpc_proc->p_name, port);
 895         if (unlikely(port > USHRT_MAX))
 896                 return -EIO;
 897 
 898         rpcb->r_port = port;
 899         return 0;
 900 }
 901 
 902 static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr,
 903                         void *data)
 904 {
 905         unsigned int *boolp = data;
 906         __be32 *p;
 907 
 908         p = xdr_inline_decode(xdr, 4);
 909         if (unlikely(p == NULL))
 910                 return -EIO;
 911 
 912         *boolp = 0;
 913         if (*p != xdr_zero)
 914                 *boolp = 1;
 915 
 916         dprintk("RPC: %5u RPCB_%s call %s\n",
 917                         req->rq_task->tk_pid,
 918                         req->rq_task->tk_msg.rpc_proc->p_name,
 919                         (*boolp ? "succeeded" : "failed"));
 920         return 0;
 921 }
 922 
 923 static void encode_rpcb_string(struct xdr_stream *xdr, const char *string,
 924                                const u32 maxstrlen)
 925 {
 926         __be32 *p;
 927         u32 len;
 928 
 929         len = strlen(string);
 930         WARN_ON_ONCE(len > maxstrlen);
 931         if (len > maxstrlen)
 932                 /* truncate and hope for the best */
 933                 len = maxstrlen;
 934         p = xdr_reserve_space(xdr, 4 + len);
 935         xdr_encode_opaque(p, string, len);
 936 }
 937 
 938 static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 939                              const void *data)
 940 {
 941         const struct rpcbind_args *rpcb = data;
 942         __be32 *p;
 943 
 944         dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n",
 945                         req->rq_task->tk_pid,
 946                         req->rq_task->tk_msg.rpc_proc->p_name,
 947                         rpcb->r_prog, rpcb->r_vers,
 948                         rpcb->r_netid, rpcb->r_addr);
 949 
 950         p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2);
 951         *p++ = cpu_to_be32(rpcb->r_prog);
 952         *p = cpu_to_be32(rpcb->r_vers);
 953 
 954         encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN);
 955         encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN);
 956         encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN);
 957 }
 958 
 959 static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
 960                             void *data)
 961 {
 962         struct rpcbind_args *rpcb = data;
 963         struct sockaddr_storage address;
 964         struct sockaddr *sap = (struct sockaddr *)&address;
 965         __be32 *p;
 966         u32 len;
 967 
 968         rpcb->r_port = 0;
 969 
 970         p = xdr_inline_decode(xdr, 4);
 971         if (unlikely(p == NULL))
 972                 goto out_fail;
 973         len = be32_to_cpup(p);
 974 
 975         /*
 976          * If the returned universal address is a null string,
 977          * the requested RPC service was not registered.
 978          */
 979         if (len == 0) {
 980                 dprintk("RPC: %5u RPCB reply: program not registered\n",
 981                                 req->rq_task->tk_pid);
 982                 return 0;
 983         }
 984 
 985         if (unlikely(len > RPCBIND_MAXUADDRLEN))
 986                 goto out_fail;
 987 
 988         p = xdr_inline_decode(xdr, len);
 989         if (unlikely(p == NULL))
 990                 goto out_fail;
 991         dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid,
 992                         req->rq_task->tk_msg.rpc_proc->p_name, (char *)p);
 993 
 994         if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len,
 995                                 sap, sizeof(address)) == 0)
 996                 goto out_fail;
 997         rpcb->r_port = rpc_get_port(sap);
 998 
 999         return 0;
1000 
1001 out_fail:
1002         dprintk("RPC: %5u malformed RPCB_%s reply\n",
1003                         req->rq_task->tk_pid,
1004                         req->rq_task->tk_msg.rpc_proc->p_name);
1005         return -EIO;
1006 }
1007 
1008 /*
1009  * Not all rpcbind procedures described in RFC 1833 are implemented
1010  * since the Linux kernel RPC code requires only these.
1011  */
1012 
1013 static const struct rpc_procinfo rpcb_procedures2[] = {
1014         [RPCBPROC_SET] = {
1015                 .p_proc         = RPCBPROC_SET,
1016                 .p_encode       = rpcb_enc_mapping,
1017                 .p_decode       = rpcb_dec_set,
1018                 .p_arglen       = RPCB_mappingargs_sz,
1019                 .p_replen       = RPCB_setres_sz,
1020                 .p_statidx      = RPCBPROC_SET,
1021                 .p_timer        = 0,
1022                 .p_name         = "SET",
1023         },
1024         [RPCBPROC_UNSET] = {
1025                 .p_proc         = RPCBPROC_UNSET,
1026                 .p_encode       = rpcb_enc_mapping,
1027                 .p_decode       = rpcb_dec_set,
1028                 .p_arglen       = RPCB_mappingargs_sz,
1029                 .p_replen       = RPCB_setres_sz,
1030                 .p_statidx      = RPCBPROC_UNSET,
1031                 .p_timer        = 0,
1032                 .p_name         = "UNSET",
1033         },
1034         [RPCBPROC_GETPORT] = {
1035                 .p_proc         = RPCBPROC_GETPORT,
1036                 .p_encode       = rpcb_enc_mapping,
1037                 .p_decode       = rpcb_dec_getport,
1038                 .p_arglen       = RPCB_mappingargs_sz,
1039                 .p_replen       = RPCB_getportres_sz,
1040                 .p_statidx      = RPCBPROC_GETPORT,
1041                 .p_timer        = 0,
1042                 .p_name         = "GETPORT",
1043         },
1044 };
1045 
1046 static const struct rpc_procinfo rpcb_procedures3[] = {
1047         [RPCBPROC_SET] = {
1048                 .p_proc         = RPCBPROC_SET,
1049                 .p_encode       = rpcb_enc_getaddr,
1050                 .p_decode       = rpcb_dec_set,
1051                 .p_arglen       = RPCB_getaddrargs_sz,
1052                 .p_replen       = RPCB_setres_sz,
1053                 .p_statidx      = RPCBPROC_SET,
1054                 .p_timer        = 0,
1055                 .p_name         = "SET",
1056         },
1057         [RPCBPROC_UNSET] = {
1058                 .p_proc         = RPCBPROC_UNSET,
1059                 .p_encode       = rpcb_enc_getaddr,
1060                 .p_decode       = rpcb_dec_set,
1061                 .p_arglen       = RPCB_getaddrargs_sz,
1062                 .p_replen       = RPCB_setres_sz,
1063                 .p_statidx      = RPCBPROC_UNSET,
1064                 .p_timer        = 0,
1065                 .p_name         = "UNSET",
1066         },
1067         [RPCBPROC_GETADDR] = {
1068                 .p_proc         = RPCBPROC_GETADDR,
1069                 .p_encode       = rpcb_enc_getaddr,
1070                 .p_decode       = rpcb_dec_getaddr,
1071                 .p_arglen       = RPCB_getaddrargs_sz,
1072                 .p_replen       = RPCB_getaddrres_sz,
1073                 .p_statidx      = RPCBPROC_GETADDR,
1074                 .p_timer        = 0,
1075                 .p_name         = "GETADDR",
1076         },
1077 };
1078 
1079 static const struct rpc_procinfo rpcb_procedures4[] = {
1080         [RPCBPROC_SET] = {
1081                 .p_proc         = RPCBPROC_SET,
1082                 .p_encode       = rpcb_enc_getaddr,
1083                 .p_decode       = rpcb_dec_set,
1084                 .p_arglen       = RPCB_getaddrargs_sz,
1085                 .p_replen       = RPCB_setres_sz,
1086                 .p_statidx      = RPCBPROC_SET,
1087                 .p_timer        = 0,
1088                 .p_name         = "SET",
1089         },
1090         [RPCBPROC_UNSET] = {
1091                 .p_proc         = RPCBPROC_UNSET,
1092                 .p_encode       = rpcb_enc_getaddr,
1093                 .p_decode       = rpcb_dec_set,
1094                 .p_arglen       = RPCB_getaddrargs_sz,
1095                 .p_replen       = RPCB_setres_sz,
1096                 .p_statidx      = RPCBPROC_UNSET,
1097                 .p_timer        = 0,
1098                 .p_name         = "UNSET",
1099         },
1100         [RPCBPROC_GETADDR] = {
1101                 .p_proc         = RPCBPROC_GETADDR,
1102                 .p_encode       = rpcb_enc_getaddr,
1103                 .p_decode       = rpcb_dec_getaddr,
1104                 .p_arglen       = RPCB_getaddrargs_sz,
1105                 .p_replen       = RPCB_getaddrres_sz,
1106                 .p_statidx      = RPCBPROC_GETADDR,
1107                 .p_timer        = 0,
1108                 .p_name         = "GETADDR",
1109         },
1110 };
1111 
1112 static const struct rpcb_info rpcb_next_version[] = {
1113         {
1114                 .rpc_vers       = RPCBVERS_2,
1115                 .rpc_proc       = &rpcb_procedures2[RPCBPROC_GETPORT],
1116         },
1117         {
1118                 .rpc_proc       = NULL,
1119         },
1120 };
1121 
1122 static const struct rpcb_info rpcb_next_version6[] = {
1123         {
1124                 .rpc_vers       = RPCBVERS_4,
1125                 .rpc_proc       = &rpcb_procedures4[RPCBPROC_GETADDR],
1126         },
1127         {
1128                 .rpc_vers       = RPCBVERS_3,
1129                 .rpc_proc       = &rpcb_procedures3[RPCBPROC_GETADDR],
1130         },
1131         {
1132                 .rpc_proc       = NULL,
1133         },
1134 };
1135 
1136 static unsigned int rpcb_version2_counts[ARRAY_SIZE(rpcb_procedures2)];
1137 static const struct rpc_version rpcb_version2 = {
1138         .number         = RPCBVERS_2,
1139         .nrprocs        = ARRAY_SIZE(rpcb_procedures2),
1140         .procs          = rpcb_procedures2,
1141         .counts         = rpcb_version2_counts,
1142 };
1143 
1144 static unsigned int rpcb_version3_counts[ARRAY_SIZE(rpcb_procedures3)];
1145 static const struct rpc_version rpcb_version3 = {
1146         .number         = RPCBVERS_3,
1147         .nrprocs        = ARRAY_SIZE(rpcb_procedures3),
1148         .procs          = rpcb_procedures3,
1149         .counts         = rpcb_version3_counts,
1150 };
1151 
1152 static unsigned int rpcb_version4_counts[ARRAY_SIZE(rpcb_procedures4)];
1153 static const struct rpc_version rpcb_version4 = {
1154         .number         = RPCBVERS_4,
1155         .nrprocs        = ARRAY_SIZE(rpcb_procedures4),
1156         .procs          = rpcb_procedures4,
1157         .counts         = rpcb_version4_counts,
1158 };
1159 
1160 static const struct rpc_version *rpcb_version[] = {
1161         NULL,
1162         NULL,
1163         &rpcb_version2,
1164         &rpcb_version3,
1165         &rpcb_version4
1166 };
1167 
1168 static struct rpc_stat rpcb_stats;
1169 
1170 static const struct rpc_program rpcb_program = {
1171         .name           = "rpcbind",
1172         .number         = RPCBIND_PROGRAM,
1173         .nrvers         = ARRAY_SIZE(rpcb_version),
1174         .version        = rpcb_version,
1175         .stats          = &rpcb_stats,
1176 };
/* [<][>][^][v][top][bottom][index][help] */
root/net/sunrpc/rpcb_clnt.c

DEFINITIONS
