~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/net/sunrpc/rpcb_clnt.c

Version: ~ [ linux-5.12 ] ~ [ linux-5.11.16 ] ~ [ linux-5.10.32 ] ~ [ linux-5.9.16 ] ~ [ linux-5.8.18 ] ~ [ linux-5.7.19 ] ~ [ linux-5.6.19 ] ~ [ linux-5.5.19 ] ~ [ linux-5.4.114 ] ~ [ linux-5.3.18 ] ~ [ linux-5.2.21 ] ~ [ linux-5.1.21 ] ~ [ linux-5.0.21 ] ~ [ linux-4.20.17 ] ~ [ linux-4.19.188 ] ~ [ linux-4.18.20 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.231 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.267 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.267 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.18.140 ] ~ [ linux-3.16.85 ] ~ [ linux-3.14.79 ] ~ [ linux-3.12.74 ] ~ [ linux-3.10.108 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  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       ""
 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 };
1177 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp