2 * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
5 * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
6 * RFC 3530: "Network File System (NFS) version 4 Protocol"
8 * Original: Gilles Quillard, Bull Open Source, 2005 <gilles.quillard@bull.net>
9 * Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
11 * Descended from net/sunrpc/pmap_clnt.c,
12 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
15 #include <linux/module.h>
17 #include <linux/types.h>
18 #include <linux/socket.h>
20 #include <linux/in6.h>
21 #include <linux/kernel.h>
22 #include <linux/errno.h>
24 #include <linux/sunrpc/clnt.h>
25 #include <linux/sunrpc/sched.h>
26 #include <linux/sunrpc/xprtsock.h>
29 # define RPCDBG_FACILITY RPCDBG_BIND
32 #define RPCBIND_PROGRAM (100000u)
33 #define RPCBIND_PORT (111u)
35 #define RPCBVERS_2 (2u)
36 #define RPCBVERS_3 (3u)
37 #define RPCBVERS_4 (4u)
44 RPCBPROC_GETADDR = 3, /* alias for GETPORT */
47 RPCBPROC_BCAST = 5, /* alias for CALLIT */
57 #define RPCB_HIGHPROC_2 RPCBPROC_CALLIT
58 #define RPCB_HIGHPROC_3 RPCBPROC_TADDR2UADDR
59 #define RPCB_HIGHPROC_4 RPCBPROC_GETSTAT
64 * The "owner" is allowed to unset a service in the rpcbind database.
65 * We always use the following (arbitrary) fixed string.
67 #define RPCB_OWNER_STRING "rpcb"
68 #define RPCB_MAXOWNERLEN sizeof(RPCB_OWNER_STRING)
70 static void rpcb_getport_done(struct rpc_task *, void *);
71 static void rpcb_map_release(void *data);
72 static struct rpc_program rpcb_program;
75 struct rpc_xprt * r_xprt;
80 unsigned short r_port;
88 static struct rpc_procinfo rpcb_procedures2[];
89 static struct rpc_procinfo rpcb_procedures3[];
93 struct rpc_procinfo * rpc_proc;
96 static struct rpcb_info rpcb_next_version[];
97 static struct rpcb_info rpcb_next_version6[];
99 static const struct rpc_call_ops rpcb_getport_ops = {
100 .rpc_call_done = rpcb_getport_done,
101 .rpc_release = rpcb_map_release,
104 static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
106 xprt_clear_binding(xprt);
107 rpc_wake_up_status(&xprt->binding, status);
110 static void rpcb_map_release(void *data)
112 struct rpcbind_args *map = data;
114 rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
115 xprt_put(map->r_xprt);
119 static const struct sockaddr_in rpcb_inaddr_loopback = {
120 .sin_family = AF_INET,
121 .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
122 .sin_port = htons(RPCBIND_PORT),
125 static struct rpc_clnt *rpcb_create_local(struct sockaddr *addr,
126 size_t addrlen, u32 version)
128 struct rpc_create_args args = {
129 .protocol = XPRT_TRANSPORT_UDP,
132 .servername = "localhost",
133 .program = &rpcb_program,
135 .authflavor = RPC_AUTH_UNIX,
136 .flags = RPC_CLNT_CREATE_NOPING,
139 return rpc_create(&args);
142 static struct rpc_clnt *rpcb_create(char *hostname, struct sockaddr *srvaddr,
143 size_t salen, int proto, u32 version)
145 struct rpc_create_args args = {
149 .servername = hostname,
150 .program = &rpcb_program,
152 .authflavor = RPC_AUTH_UNIX,
153 .flags = (RPC_CLNT_CREATE_NOPING |
154 RPC_CLNT_CREATE_NONPRIVPORT),
157 switch (srvaddr->sa_family) {
159 ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
162 ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
168 return rpc_create(&args);
172 * rpcb_register - set or unset a port registration with the local rpcbind svc
173 * @prog: RPC program number to bind
174 * @vers: RPC version number to bind
175 * @prot: transport protocol to use to make this request
176 * @port: port value to register
179 * port == 0 means unregister, port != 0 means register.
181 * This routine supports only rpcbind version 2.
183 int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
185 struct rpcbind_args map = {
191 struct rpc_message msg = {
192 .rpc_proc = &rpcb_procedures2[port ?
193 RPCBPROC_SET : RPCBPROC_UNSET],
197 struct rpc_clnt *rpcb_clnt;
200 dprintk("RPC: %sregistering (%u, %u, %d, %u) with local "
201 "rpcbind\n", (port ? "" : "un"),
202 prog, vers, prot, port);
204 rpcb_clnt = rpcb_create_local((struct sockaddr *)&rpcb_inaddr_loopback,
205 sizeof(rpcb_inaddr_loopback),
207 if (!IS_ERR(rpcb_clnt)) {
208 error = rpc_call_sync(rpcb_clnt, &msg, 0);
209 rpc_shutdown_client(rpcb_clnt);
211 error = PTR_ERR(rpcb_clnt);
214 printk(KERN_WARNING "RPC: failed to contact local rpcbind "
215 "server (errno %d).\n", -error);
216 dprintk("RPC: registration status %d/%d\n", error, *okay);
222 * rpcb_getport_sync - obtain the port for an RPC service on a given host
223 * @sin: address of remote peer
224 * @prog: RPC program number to bind
225 * @vers: RPC version number to bind
226 * @prot: transport protocol to use to make this request
228 * Return value is the requested advertised port number,
229 * or a negative errno value.
231 * Called from outside the RPC client in a synchronous task context.
232 * Uses default timeout parameters specified by underlying transport.
234 * XXX: Needs to support IPv6
236 int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
238 struct rpcbind_args map = {
244 struct rpc_message msg = {
245 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT],
247 .rpc_resp = &map.r_port,
249 struct rpc_clnt *rpcb_clnt;
252 dprintk("RPC: %s(" NIPQUAD_FMT ", %u, %u, %d)\n",
253 __func__, NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
255 rpcb_clnt = rpcb_create(NULL, (struct sockaddr *)sin,
256 sizeof(*sin), prot, RPCBVERS_2);
257 if (IS_ERR(rpcb_clnt))
258 return PTR_ERR(rpcb_clnt);
260 status = rpc_call_sync(rpcb_clnt, &msg, 0);
261 rpc_shutdown_client(rpcb_clnt);
270 EXPORT_SYMBOL_GPL(rpcb_getport_sync);
272 static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
274 struct rpc_message msg = {
277 .rpc_resp = &map->r_port,
279 struct rpc_task_setup task_setup_data = {
280 .rpc_client = rpcb_clnt,
282 .callback_ops = &rpcb_getport_ops,
283 .callback_data = map,
284 .flags = RPC_TASK_ASYNC,
287 return rpc_run_task(&task_setup_data);
291 * rpcb_getport_async - obtain the port for a given RPC service on a given host
292 * @task: task that is waiting for portmapper request
294 * This one can be called for an ongoing RPC request, and can be used in
295 * an async (rpciod) context.
297 void rpcb_getport_async(struct rpc_task *task)
299 struct rpc_clnt *clnt = task->tk_client;
300 struct rpc_procinfo *proc;
302 struct rpc_xprt *xprt = task->tk_xprt;
303 struct rpc_clnt *rpcb_clnt;
304 static struct rpcbind_args *map;
305 struct rpc_task *child;
306 struct sockaddr_storage addr;
307 struct sockaddr *sap = (struct sockaddr *)&addr;
311 dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
312 task->tk_pid, __func__,
313 clnt->cl_server, clnt->cl_prog, clnt->cl_vers, xprt->prot);
315 /* Autobind on cloned rpc clients is discouraged */
316 BUG_ON(clnt->cl_parent != clnt);
318 /* Put self on the wait queue to ensure we get notified if
319 * some other task is already attempting to bind the port */
320 rpc_sleep_on(&xprt->binding, task, NULL);
322 if (xprt_test_and_set_binding(xprt)) {
323 dprintk("RPC: %5u %s: waiting for another binder\n",
324 task->tk_pid, __func__);
328 /* Someone else may have bound if we slept */
329 if (xprt_bound(xprt)) {
331 dprintk("RPC: %5u %s: already bound\n",
332 task->tk_pid, __func__);
336 salen = rpc_peeraddr(clnt, sap, sizeof(addr));
338 /* Don't ever use rpcbind v2 for AF_INET6 requests */
339 switch (sap->sa_family) {
341 proc = rpcb_next_version[xprt->bind_index].rpc_proc;
342 bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
345 proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
346 bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
349 status = -EAFNOSUPPORT;
350 dprintk("RPC: %5u %s: bad address family\n",
351 task->tk_pid, __func__);
355 xprt->bind_index = 0;
356 status = -EPFNOSUPPORT;
357 dprintk("RPC: %5u %s: no more getport versions available\n",
358 task->tk_pid, __func__);
362 dprintk("RPC: %5u %s: trying rpcbind version %u\n",
363 task->tk_pid, __func__, bind_version);
365 rpcb_clnt = rpcb_create(clnt->cl_server, sap, salen, xprt->prot,
367 if (IS_ERR(rpcb_clnt)) {
368 status = PTR_ERR(rpcb_clnt);
369 dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
370 task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
374 map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
377 dprintk("RPC: %5u %s: no memory available\n",
378 task->tk_pid, __func__);
381 map->r_prog = clnt->cl_prog;
382 map->r_vers = clnt->cl_vers;
383 map->r_prot = xprt->prot;
385 map->r_xprt = xprt_get(xprt);
386 map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
387 map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
388 map->r_owner = RPCB_OWNER_STRING; /* ignored for GETADDR */
389 map->r_status = -EIO;
391 child = rpcb_call_async(rpcb_clnt, map, proc);
392 rpc_release_client(rpcb_clnt);
394 /* rpcb_map_release() has freed the arguments */
395 dprintk("RPC: %5u %s: rpc_run_task failed\n",
396 task->tk_pid, __func__);
401 task->tk_xprt->stat.bind_count++;
405 rpcb_wake_rpcbind_waiters(xprt, status);
406 task->tk_status = status;
408 EXPORT_SYMBOL_GPL(rpcb_getport_async);
411 * Rpcbind child task calls this callback via tk_exit.
413 static void rpcb_getport_done(struct rpc_task *child, void *data)
415 struct rpcbind_args *map = data;
416 struct rpc_xprt *xprt = map->r_xprt;
417 int status = child->tk_status;
419 /* Garbage reply: retry with a lesser rpcbind version */
421 status = -EPROTONOSUPPORT;
423 /* rpcbind server doesn't support this rpcbind protocol version */
424 if (status == -EPROTONOSUPPORT)
428 /* rpcbind server not available on remote host? */
429 xprt->ops->set_port(xprt, 0);
430 } else if (map->r_port == 0) {
431 /* Requested RPC service wasn't registered on remote host */
432 xprt->ops->set_port(xprt, 0);
436 xprt->ops->set_port(xprt, map->r_port);
437 xprt_set_bound(xprt);
441 dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
442 child->tk_pid, status, map->r_port);
444 map->r_status = status;
448 * XDR functions for rpcbind
451 static int rpcb_encode_mapping(struct rpc_rqst *req, __be32 *p,
452 struct rpcbind_args *rpcb)
454 dprintk("RPC: rpcb_encode_mapping(%u, %u, %d, %u)\n",
455 rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
456 *p++ = htonl(rpcb->r_prog);
457 *p++ = htonl(rpcb->r_vers);
458 *p++ = htonl(rpcb->r_prot);
459 *p++ = htonl(rpcb->r_port);
461 req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
465 static int rpcb_decode_getport(struct rpc_rqst *req, __be32 *p,
466 unsigned short *portp)
468 *portp = (unsigned short) ntohl(*p++);
469 dprintk("RPC: rpcb_decode_getport result %u\n",
474 static int rpcb_decode_set(struct rpc_rqst *req, __be32 *p,
477 *boolp = (unsigned int) ntohl(*p++);
478 dprintk("RPC: rpcb_decode_set: call %s\n",
479 (*boolp ? "succeeded" : "failed"));
483 static int rpcb_encode_getaddr(struct rpc_rqst *req, __be32 *p,
484 struct rpcbind_args *rpcb)
486 dprintk("RPC: rpcb_encode_getaddr(%u, %u, %s)\n",
487 rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
488 *p++ = htonl(rpcb->r_prog);
489 *p++ = htonl(rpcb->r_vers);
491 p = xdr_encode_string(p, rpcb->r_netid);
492 p = xdr_encode_string(p, rpcb->r_addr);
493 p = xdr_encode_string(p, rpcb->r_owner);
495 req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
500 static int rpcb_decode_getaddr(struct rpc_rqst *req, __be32 *p,
501 unsigned short *portp)
505 int c, i, f, first, val;
508 addr_len = ntohl(*p++);
511 * Simple sanity check. The smallest possible universal
512 * address is an IPv4 address string containing 11 bytes.
514 if (addr_len < 11 || addr_len > RPCBIND_MAXUADDRLEN)
518 * Start at the end and walk backwards until the first dot
519 * is encountered. When the second dot is found, we have
520 * both parts of the port number.
526 for (i = addr_len - 1; i > 0; i--) {
528 if (c >= '0' && c <= '9') {
529 val += (c - '0') * f;
531 } else if (c == '.') {
537 *portp |= (val << 8);
544 * Simple sanity check. If we never saw a dot in the reply,
545 * then this was probably just garbage.
550 dprintk("RPC: rpcb_decode_getaddr port=%u\n", *portp);
554 dprintk("RPC: rpcbind server returned malformed reply\n");
558 #define RPCB_program_sz (1u)
559 #define RPCB_version_sz (1u)
560 #define RPCB_protocol_sz (1u)
561 #define RPCB_port_sz (1u)
562 #define RPCB_boolean_sz (1u)
564 #define RPCB_netid_sz (1+XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
565 #define RPCB_addr_sz (1+XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
566 #define RPCB_ownerstring_sz (1+XDR_QUADLEN(RPCB_MAXOWNERLEN))
568 #define RPCB_mappingargs_sz RPCB_program_sz+RPCB_version_sz+ \
569 RPCB_protocol_sz+RPCB_port_sz
570 #define RPCB_getaddrargs_sz RPCB_program_sz+RPCB_version_sz+ \
571 RPCB_netid_sz+RPCB_addr_sz+ \
574 #define RPCB_setres_sz RPCB_boolean_sz
575 #define RPCB_getportres_sz RPCB_port_sz
578 * Note that RFC 1833 does not put any size restrictions on the
579 * address string returned by the remote rpcbind database.
581 #define RPCB_getaddrres_sz RPCB_addr_sz
583 #define PROC(proc, argtype, restype) \
584 [RPCBPROC_##proc] = { \
585 .p_proc = RPCBPROC_##proc, \
586 .p_encode = (kxdrproc_t) rpcb_encode_##argtype, \
587 .p_decode = (kxdrproc_t) rpcb_decode_##restype, \
588 .p_arglen = RPCB_##argtype##args_sz, \
589 .p_replen = RPCB_##restype##res_sz, \
590 .p_statidx = RPCBPROC_##proc, \
596 * Not all rpcbind procedures described in RFC 1833 are implemented
597 * since the Linux kernel RPC code requires only these.
599 static struct rpc_procinfo rpcb_procedures2[] = {
600 PROC(SET, mapping, set),
601 PROC(UNSET, mapping, set),
602 PROC(GETPORT, mapping, getport),
605 static struct rpc_procinfo rpcb_procedures3[] = {
606 PROC(SET, getaddr, set),
607 PROC(UNSET, getaddr, set),
608 PROC(GETADDR, getaddr, getaddr),
611 static struct rpc_procinfo rpcb_procedures4[] = {
612 PROC(SET, getaddr, set),
613 PROC(UNSET, getaddr, set),
614 PROC(GETADDR, getaddr, getaddr),
615 PROC(GETVERSADDR, getaddr, getaddr),
618 static struct rpcb_info rpcb_next_version[] = {
620 .rpc_vers = RPCBVERS_2,
621 .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT],
628 static struct rpcb_info rpcb_next_version6[] = {
630 .rpc_vers = RPCBVERS_4,
631 .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR],
634 .rpc_vers = RPCBVERS_3,
635 .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR],
642 static struct rpc_version rpcb_version2 = {
643 .number = RPCBVERS_2,
644 .nrprocs = RPCB_HIGHPROC_2,
645 .procs = rpcb_procedures2
648 static struct rpc_version rpcb_version3 = {
649 .number = RPCBVERS_3,
650 .nrprocs = RPCB_HIGHPROC_3,
651 .procs = rpcb_procedures3
654 static struct rpc_version rpcb_version4 = {
655 .number = RPCBVERS_4,
656 .nrprocs = RPCB_HIGHPROC_4,
657 .procs = rpcb_procedures4
660 static struct rpc_version *rpcb_version[] = {
668 static struct rpc_stat rpcb_stats;
670 static struct rpc_program rpcb_program = {
672 .number = RPCBIND_PROGRAM,
673 .nrvers = ARRAY_SIZE(rpcb_version),
674 .version = rpcb_version,
675 .stats = &rpcb_stats,