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 <trace/events/sunrpc.h> |
35 | |
36 | #include "netns.h" |
37 | |
38 | #define RPCBIND_SOCK_PATHNAME "/var/run/rpcbind.sock" |
39 | #define RPCBIND_SOCK_ABSTRACT_NAME "\0/run/rpcbind.sock" |
40 | |
41 | #define RPCBIND_PROGRAM (100000u) |
42 | #define RPCBIND_PORT (111u) |
43 | |
44 | #define RPCBVERS_2 (2u) |
45 | #define RPCBVERS_3 (3u) |
46 | #define RPCBVERS_4 (4u) |
47 | |
48 | enum { |
49 | RPCBPROC_NULL, |
50 | RPCBPROC_SET, |
51 | RPCBPROC_UNSET, |
52 | RPCBPROC_GETPORT, |
53 | RPCBPROC_GETADDR = 3, /* alias for GETPORT */ |
54 | RPCBPROC_DUMP, |
55 | RPCBPROC_CALLIT, |
56 | RPCBPROC_BCAST = 5, /* alias for CALLIT */ |
57 | RPCBPROC_GETTIME, |
58 | RPCBPROC_UADDR2TADDR, |
59 | RPCBPROC_TADDR2UADDR, |
60 | RPCBPROC_GETVERSADDR, |
61 | RPCBPROC_INDIRECT, |
62 | RPCBPROC_GETADDRLIST, |
63 | RPCBPROC_GETSTAT, |
64 | }; |
65 | |
66 | /* |
67 | * r_owner |
68 | * |
69 | * The "owner" is allowed to unset a service in the rpcbind database. |
70 | * |
71 | * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a |
72 | * UID which it maps to a local user name via a password lookup. |
73 | * In all other cases it is ignored. |
74 | * |
75 | * For SET/UNSET requests, user space provides a value, even for |
76 | * network requests, and GETADDR uses an empty string. We follow |
77 | * those precedents here. |
78 | */ |
79 | #define RPCB_OWNER_STRING "0" |
80 | #define RPCB_MAXOWNERLEN sizeof(RPCB_OWNER_STRING) |
81 | |
82 | /* |
83 | * XDR data type sizes |
84 | */ |
85 | #define RPCB_program_sz (1) |
86 | #define RPCB_version_sz (1) |
87 | #define RPCB_protocol_sz (1) |
88 | #define RPCB_port_sz (1) |
89 | #define RPCB_boolean_sz (1) |
90 | |
91 | #define RPCB_netid_sz (1 + XDR_QUADLEN(RPCBIND_MAXNETIDLEN)) |
92 | #define RPCB_addr_sz (1 + XDR_QUADLEN(RPCBIND_MAXUADDRLEN)) |
93 | #define RPCB_ownerstring_sz (1 + XDR_QUADLEN(RPCB_MAXOWNERLEN)) |
94 | |
95 | /* |
96 | * XDR argument and result sizes |
97 | */ |
98 | #define RPCB_mappingargs_sz (RPCB_program_sz + RPCB_version_sz + \ |
99 | RPCB_protocol_sz + RPCB_port_sz) |
100 | #define RPCB_getaddrargs_sz (RPCB_program_sz + RPCB_version_sz + \ |
101 | RPCB_netid_sz + RPCB_addr_sz + \ |
102 | RPCB_ownerstring_sz) |
103 | |
104 | #define RPCB_getportres_sz RPCB_port_sz |
105 | #define RPCB_setres_sz RPCB_boolean_sz |
106 | |
107 | /* |
108 | * Note that RFC 1833 does not put any size restrictions on the |
109 | * address string returned by the remote rpcbind database. |
110 | */ |
111 | #define RPCB_getaddrres_sz RPCB_addr_sz |
112 | |
113 | static void rpcb_getport_done(struct rpc_task *, void *); |
114 | static void rpcb_map_release(void *data); |
115 | static const struct rpc_program rpcb_program; |
116 | |
117 | struct rpcbind_args { |
118 | struct rpc_xprt * r_xprt; |
119 | |
120 | u32 r_prog; |
121 | u32 r_vers; |
122 | u32 r_prot; |
123 | unsigned short r_port; |
124 | const char * r_netid; |
125 | const char * r_addr; |
126 | const char * r_owner; |
127 | |
128 | int r_status; |
129 | }; |
130 | |
131 | static const struct rpc_procinfo rpcb_procedures2[]; |
132 | static const struct rpc_procinfo rpcb_procedures3[]; |
133 | static const struct rpc_procinfo rpcb_procedures4[]; |
134 | |
135 | struct rpcb_info { |
136 | u32 rpc_vers; |
137 | const struct rpc_procinfo *rpc_proc; |
138 | }; |
139 | |
140 | static const struct rpcb_info rpcb_next_version[]; |
141 | static const struct rpcb_info rpcb_next_version6[]; |
142 | |
143 | static const struct rpc_call_ops rpcb_getport_ops = { |
144 | .rpc_call_done = rpcb_getport_done, |
145 | .rpc_release = rpcb_map_release, |
146 | }; |
147 | |
148 | static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status) |
149 | { |
150 | xprt_clear_binding(xprt); |
151 | rpc_wake_up_status(&xprt->binding, status); |
152 | } |
153 | |
154 | static void rpcb_map_release(void *data) |
155 | { |
156 | struct rpcbind_args *map = data; |
157 | |
158 | rpcb_wake_rpcbind_waiters(xprt: map->r_xprt, status: map->r_status); |
159 | xprt_put(xprt: map->r_xprt); |
160 | kfree(objp: map->r_addr); |
161 | kfree(objp: map); |
162 | } |
163 | |
164 | static int rpcb_get_local(struct net *net) |
165 | { |
166 | int cnt; |
167 | struct sunrpc_net *sn = net_generic(net, id: sunrpc_net_id); |
168 | |
169 | spin_lock(lock: &sn->rpcb_clnt_lock); |
170 | if (sn->rpcb_users) |
171 | sn->rpcb_users++; |
172 | cnt = sn->rpcb_users; |
173 | spin_unlock(lock: &sn->rpcb_clnt_lock); |
174 | |
175 | return cnt; |
176 | } |
177 | |
178 | void rpcb_put_local(struct net *net) |
179 | { |
180 | struct sunrpc_net *sn = net_generic(net, id: sunrpc_net_id); |
181 | struct rpc_clnt *clnt = sn->rpcb_local_clnt; |
182 | struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4; |
183 | int shutdown = 0; |
184 | |
185 | spin_lock(lock: &sn->rpcb_clnt_lock); |
186 | if (sn->rpcb_users) { |
187 | if (--sn->rpcb_users == 0) { |
188 | sn->rpcb_local_clnt = NULL; |
189 | sn->rpcb_local_clnt4 = NULL; |
190 | } |
191 | shutdown = !sn->rpcb_users; |
192 | } |
193 | spin_unlock(lock: &sn->rpcb_clnt_lock); |
194 | |
195 | if (shutdown) { |
196 | /* |
197 | * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister |
198 | */ |
199 | if (clnt4) |
200 | rpc_shutdown_client(clnt4); |
201 | if (clnt) |
202 | rpc_shutdown_client(clnt); |
203 | } |
204 | } |
205 | |
206 | static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt, |
207 | struct rpc_clnt *clnt4, |
208 | bool is_af_local) |
209 | { |
210 | struct sunrpc_net *sn = net_generic(net, id: sunrpc_net_id); |
211 | |
212 | /* Protected by rpcb_create_local_mutex */ |
213 | sn->rpcb_local_clnt = clnt; |
214 | sn->rpcb_local_clnt4 = clnt4; |
215 | sn->rpcb_is_af_local = is_af_local ? 1 : 0; |
216 | smp_wmb(); |
217 | sn->rpcb_users = 1; |
218 | } |
219 | |
220 | /* Evaluate to actual length of the `sockaddr_un' structure. */ |
221 | # define SUN_LEN(ptr) (offsetof(struct sockaddr_un, sun_path) \ |
222 | + 1 + strlen((ptr)->sun_path + 1)) |
223 | |
224 | /* |
225 | * Returns zero on success, otherwise a negative errno value |
226 | * is returned. |
227 | */ |
228 | static int rpcb_create_af_local(struct net *net, |
229 | const struct sockaddr_un *addr) |
230 | { |
231 | struct rpc_create_args args = { |
232 | .net = net, |
233 | .protocol = XPRT_TRANSPORT_LOCAL, |
234 | .address = (struct sockaddr *)addr, |
235 | .addrsize = SUN_LEN(addr), |
236 | .servername = "localhost" , |
237 | .program = &rpcb_program, |
238 | .version = RPCBVERS_2, |
239 | .authflavor = RPC_AUTH_NULL, |
240 | .cred = current_cred(), |
241 | /* |
242 | * We turn off the idle timeout to prevent the kernel |
243 | * from automatically disconnecting the socket. |
244 | * Otherwise, we'd have to cache the mount namespace |
245 | * of the caller and somehow pass that to the socket |
246 | * reconnect code. |
247 | */ |
248 | .flags = RPC_CLNT_CREATE_NO_IDLE_TIMEOUT, |
249 | }; |
250 | struct rpc_clnt *clnt, *clnt4; |
251 | int result = 0; |
252 | |
253 | /* |
254 | * Because we requested an RPC PING at transport creation time, |
255 | * this works only if the user space portmapper is rpcbind, and |
256 | * it's listening on AF_LOCAL on the named socket. |
257 | */ |
258 | clnt = rpc_create(args: &args); |
259 | if (IS_ERR(ptr: clnt)) { |
260 | result = PTR_ERR(ptr: clnt); |
261 | goto out; |
262 | } |
263 | |
264 | clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); |
265 | if (IS_ERR(ptr: clnt4)) |
266 | clnt4 = NULL; |
267 | |
268 | rpcb_set_local(net, clnt, clnt4, is_af_local: true); |
269 | |
270 | out: |
271 | return result; |
272 | } |
273 | |
274 | static int rpcb_create_local_abstract(struct net *net) |
275 | { |
276 | static const struct sockaddr_un rpcb_localaddr_abstract = { |
277 | .sun_family = AF_LOCAL, |
278 | .sun_path = RPCBIND_SOCK_ABSTRACT_NAME, |
279 | }; |
280 | |
281 | return rpcb_create_af_local(net, addr: &rpcb_localaddr_abstract); |
282 | } |
283 | |
284 | static int rpcb_create_local_unix(struct net *net) |
285 | { |
286 | static const struct sockaddr_un rpcb_localaddr_unix = { |
287 | .sun_family = AF_LOCAL, |
288 | .sun_path = RPCBIND_SOCK_PATHNAME, |
289 | }; |
290 | |
291 | return rpcb_create_af_local(net, addr: &rpcb_localaddr_unix); |
292 | } |
293 | |
294 | /* |
295 | * Returns zero on success, otherwise a negative errno value |
296 | * is returned. |
297 | */ |
298 | static int rpcb_create_local_net(struct net *net) |
299 | { |
300 | static const struct sockaddr_in rpcb_inaddr_loopback = { |
301 | .sin_family = AF_INET, |
302 | .sin_addr.s_addr = htonl(INADDR_LOOPBACK), |
303 | .sin_port = htons(RPCBIND_PORT), |
304 | }; |
305 | struct rpc_create_args args = { |
306 | .net = net, |
307 | .protocol = XPRT_TRANSPORT_TCP, |
308 | .address = (struct sockaddr *)&rpcb_inaddr_loopback, |
309 | .addrsize = sizeof(rpcb_inaddr_loopback), |
310 | .servername = "localhost" , |
311 | .program = &rpcb_program, |
312 | .version = RPCBVERS_2, |
313 | .authflavor = RPC_AUTH_UNIX, |
314 | .cred = current_cred(), |
315 | .flags = RPC_CLNT_CREATE_NOPING, |
316 | }; |
317 | struct rpc_clnt *clnt, *clnt4; |
318 | int result = 0; |
319 | |
320 | clnt = rpc_create(args: &args); |
321 | if (IS_ERR(ptr: clnt)) { |
322 | result = PTR_ERR(ptr: clnt); |
323 | goto out; |
324 | } |
325 | |
326 | /* |
327 | * This results in an RPC ping. On systems running portmapper, |
328 | * the v4 ping will fail. Proceed anyway, but disallow rpcb |
329 | * v4 upcalls. |
330 | */ |
331 | clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); |
332 | if (IS_ERR(ptr: clnt4)) |
333 | clnt4 = NULL; |
334 | |
335 | rpcb_set_local(net, clnt, clnt4, is_af_local: false); |
336 | |
337 | out: |
338 | return result; |
339 | } |
340 | |
341 | /* |
342 | * Returns zero on success, otherwise a negative errno value |
343 | * is returned. |
344 | */ |
345 | int rpcb_create_local(struct net *net) |
346 | { |
347 | static DEFINE_MUTEX(rpcb_create_local_mutex); |
348 | int result = 0; |
349 | |
350 | if (rpcb_get_local(net)) |
351 | return result; |
352 | |
353 | mutex_lock(&rpcb_create_local_mutex); |
354 | if (rpcb_get_local(net)) |
355 | goto out; |
356 | |
357 | if (rpcb_create_local_abstract(net) != 0 && |
358 | rpcb_create_local_unix(net) != 0) |
359 | result = rpcb_create_local_net(net); |
360 | |
361 | out: |
362 | mutex_unlock(lock: &rpcb_create_local_mutex); |
363 | return result; |
364 | } |
365 | |
366 | static struct rpc_clnt *rpcb_create(struct net *net, const char *nodename, |
367 | const char *hostname, |
368 | struct sockaddr *srvaddr, size_t salen, |
369 | int proto, u32 version, |
370 | const struct cred *cred, |
371 | const struct rpc_timeout *timeo) |
372 | { |
373 | struct rpc_create_args args = { |
374 | .net = net, |
375 | .protocol = proto, |
376 | .address = srvaddr, |
377 | .addrsize = salen, |
378 | .timeout = timeo, |
379 | .servername = hostname, |
380 | .nodename = nodename, |
381 | .program = &rpcb_program, |
382 | .version = version, |
383 | .authflavor = RPC_AUTH_UNIX, |
384 | .cred = cred, |
385 | .flags = (RPC_CLNT_CREATE_NOPING | |
386 | RPC_CLNT_CREATE_NONPRIVPORT), |
387 | }; |
388 | |
389 | switch (srvaddr->sa_family) { |
390 | case AF_INET: |
391 | ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT); |
392 | break; |
393 | case AF_INET6: |
394 | ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT); |
395 | break; |
396 | default: |
397 | return ERR_PTR(error: -EAFNOSUPPORT); |
398 | } |
399 | |
400 | return rpc_create(args: &args); |
401 | } |
402 | |
403 | static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set) |
404 | { |
405 | int flags = RPC_TASK_NOCONNECT; |
406 | int error, result = 0; |
407 | |
408 | if (is_set || !sn->rpcb_is_af_local) |
409 | flags = RPC_TASK_SOFTCONN; |
410 | msg->rpc_resp = &result; |
411 | |
412 | error = rpc_call_sync(clnt, msg, flags); |
413 | if (error < 0) |
414 | return error; |
415 | |
416 | if (!result) |
417 | return -EACCES; |
418 | return 0; |
419 | } |
420 | |
421 | /** |
422 | * rpcb_register - set or unset a port registration with the local rpcbind svc |
423 | * @net: target network namespace |
424 | * @prog: RPC program number to bind |
425 | * @vers: RPC version number to bind |
426 | * @prot: transport protocol to register |
427 | * @port: port value to register |
428 | * |
429 | * Returns zero if the registration request was dispatched successfully |
430 | * and the rpcbind daemon returned success. Otherwise, returns an errno |
431 | * value that reflects the nature of the error (request could not be |
432 | * dispatched, timed out, or rpcbind returned an error). |
433 | * |
434 | * RPC services invoke this function to advertise their contact |
435 | * information via the system's rpcbind daemon. RPC services |
436 | * invoke this function once for each [program, version, transport] |
437 | * tuple they wish to advertise. |
438 | * |
439 | * Callers may also unregister RPC services that are no longer |
440 | * available by setting the passed-in port to zero. This removes |
441 | * all registered transports for [program, version] from the local |
442 | * rpcbind database. |
443 | * |
444 | * This function uses rpcbind protocol version 2 to contact the |
445 | * local rpcbind daemon. |
446 | * |
447 | * Registration works over both AF_INET and AF_INET6, and services |
448 | * registered via this function are advertised as available for any |
449 | * address. If the local rpcbind daemon is listening on AF_INET6, |
450 | * services registered via this function will be advertised on |
451 | * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6 |
452 | * addresses). |
453 | */ |
454 | int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port) |
455 | { |
456 | struct rpcbind_args map = { |
457 | .r_prog = prog, |
458 | .r_vers = vers, |
459 | .r_prot = prot, |
460 | .r_port = port, |
461 | }; |
462 | struct rpc_message msg = { |
463 | .rpc_argp = &map, |
464 | }; |
465 | struct sunrpc_net *sn = net_generic(net, id: sunrpc_net_id); |
466 | bool is_set = false; |
467 | |
468 | trace_pmap_register(program: prog, version: vers, protocol: prot, port); |
469 | |
470 | msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET]; |
471 | if (port != 0) { |
472 | msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET]; |
473 | is_set = true; |
474 | } |
475 | |
476 | return rpcb_register_call(sn, clnt: sn->rpcb_local_clnt, msg: &msg, is_set); |
477 | } |
478 | |
479 | /* |
480 | * Fill in AF_INET family-specific arguments to register |
481 | */ |
482 | static int rpcb_register_inet4(struct sunrpc_net *sn, |
483 | const struct sockaddr *sap, |
484 | struct rpc_message *msg) |
485 | { |
486 | const struct sockaddr_in *sin = (const struct sockaddr_in *)sap; |
487 | struct rpcbind_args *map = msg->rpc_argp; |
488 | unsigned short port = ntohs(sin->sin_port); |
489 | bool is_set = false; |
490 | int result; |
491 | |
492 | map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); |
493 | |
494 | msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; |
495 | if (port != 0) { |
496 | msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; |
497 | is_set = true; |
498 | } |
499 | |
500 | result = rpcb_register_call(sn, clnt: sn->rpcb_local_clnt4, msg, is_set); |
501 | kfree(objp: map->r_addr); |
502 | return result; |
503 | } |
504 | |
505 | /* |
506 | * Fill in AF_INET6 family-specific arguments to register |
507 | */ |
508 | static int rpcb_register_inet6(struct sunrpc_net *sn, |
509 | const struct sockaddr *sap, |
510 | struct rpc_message *msg) |
511 | { |
512 | const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap; |
513 | struct rpcbind_args *map = msg->rpc_argp; |
514 | unsigned short port = ntohs(sin6->sin6_port); |
515 | bool is_set = false; |
516 | int result; |
517 | |
518 | map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL); |
519 | |
520 | msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; |
521 | if (port != 0) { |
522 | msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET]; |
523 | is_set = true; |
524 | } |
525 | |
526 | result = rpcb_register_call(sn, clnt: sn->rpcb_local_clnt4, msg, is_set); |
527 | kfree(objp: map->r_addr); |
528 | return result; |
529 | } |
530 | |
531 | static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn, |
532 | struct rpc_message *msg) |
533 | { |
534 | struct rpcbind_args *map = msg->rpc_argp; |
535 | |
536 | trace_rpcb_unregister(program: map->r_prog, version: map->r_vers, netid: map->r_netid); |
537 | |
538 | map->r_addr = "" ; |
539 | msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET]; |
540 | |
541 | return rpcb_register_call(sn, clnt: sn->rpcb_local_clnt4, msg, is_set: false); |
542 | } |
543 | |
544 | /** |
545 | * rpcb_v4_register - set or unset a port registration with the local rpcbind |
546 | * @net: target network namespace |
547 | * @program: RPC program number of service to (un)register |
548 | * @version: RPC version number of service to (un)register |
549 | * @address: address family, IP address, and port to (un)register |
550 | * @netid: netid of transport protocol to (un)register |
551 | * |
552 | * Returns zero if the registration request was dispatched successfully |
553 | * and the rpcbind daemon returned success. Otherwise, returns an errno |
554 | * value that reflects the nature of the error (request could not be |
555 | * dispatched, timed out, or rpcbind returned an error). |
556 | * |
557 | * RPC services invoke this function to advertise their contact |
558 | * information via the system's rpcbind daemon. RPC services |
559 | * invoke this function once for each [program, version, address, |
560 | * netid] tuple they wish to advertise. |
561 | * |
562 | * Callers may also unregister RPC services that are registered at a |
563 | * specific address by setting the port number in @address to zero. |
564 | * They may unregister all registered protocol families at once for |
565 | * a service by passing a NULL @address argument. If @netid is "" |
566 | * then all netids for [program, version, address] are unregistered. |
567 | * |
568 | * This function uses rpcbind protocol version 4 to contact the |
569 | * local rpcbind daemon. The local rpcbind daemon must support |
570 | * version 4 of the rpcbind protocol in order for these functions |
571 | * to register a service successfully. |
572 | * |
573 | * Supported netids include "udp" and "tcp" for UDP and TCP over |
574 | * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6, |
575 | * respectively. |
576 | * |
577 | * The contents of @address determine the address family and the |
578 | * port to be registered. The usual practice is to pass INADDR_ANY |
579 | * as the raw address, but specifying a non-zero address is also |
580 | * supported by this API if the caller wishes to advertise an RPC |
581 | * service on a specific network interface. |
582 | * |
583 | * Note that passing in INADDR_ANY does not create the same service |
584 | * registration as IN6ADDR_ANY. The former advertises an RPC |
585 | * service on any IPv4 address, but not on IPv6. The latter |
586 | * advertises the service on all IPv4 and IPv6 addresses. |
587 | */ |
588 | int rpcb_v4_register(struct net *net, const u32 program, const u32 version, |
589 | const struct sockaddr *address, const char *netid) |
590 | { |
591 | struct rpcbind_args map = { |
592 | .r_prog = program, |
593 | .r_vers = version, |
594 | .r_netid = netid, |
595 | .r_owner = RPCB_OWNER_STRING, |
596 | }; |
597 | struct rpc_message msg = { |
598 | .rpc_argp = &map, |
599 | }; |
600 | struct sunrpc_net *sn = net_generic(net, id: sunrpc_net_id); |
601 | |
602 | if (sn->rpcb_local_clnt4 == NULL) |
603 | return -EPROTONOSUPPORT; |
604 | |
605 | if (address == NULL) |
606 | return rpcb_unregister_all_protofamilies(sn, msg: &msg); |
607 | |
608 | trace_rpcb_register(program: map.r_prog, version: map.r_vers, addr: map.r_addr, netid: map.r_netid); |
609 | |
610 | switch (address->sa_family) { |
611 | case AF_INET: |
612 | return rpcb_register_inet4(sn, sap: address, msg: &msg); |
613 | case AF_INET6: |
614 | return rpcb_register_inet6(sn, sap: address, msg: &msg); |
615 | } |
616 | |
617 | return -EAFNOSUPPORT; |
618 | } |
619 | |
620 | static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, |
621 | struct rpcbind_args *map, const struct rpc_procinfo *proc) |
622 | { |
623 | struct rpc_message msg = { |
624 | .rpc_proc = proc, |
625 | .rpc_argp = map, |
626 | .rpc_resp = map, |
627 | }; |
628 | struct rpc_task_setup task_setup_data = { |
629 | .rpc_client = rpcb_clnt, |
630 | .rpc_message = &msg, |
631 | .callback_ops = &rpcb_getport_ops, |
632 | .callback_data = map, |
633 | .flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN, |
634 | }; |
635 | |
636 | return rpc_run_task(&task_setup_data); |
637 | } |
638 | |
639 | /* |
640 | * In the case where rpc clients have been cloned, we want to make |
641 | * sure that we use the program number/version etc of the actual |
642 | * owner of the xprt. To do so, we walk back up the tree of parents |
643 | * to find whoever created the transport and/or whoever has the |
644 | * autobind flag set. |
645 | */ |
646 | static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt) |
647 | { |
648 | struct rpc_clnt *parent = clnt->cl_parent; |
649 | struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch); |
650 | |
651 | while (parent != clnt) { |
652 | if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps) |
653 | break; |
654 | if (clnt->cl_autobind) |
655 | break; |
656 | clnt = parent; |
657 | parent = parent->cl_parent; |
658 | } |
659 | return clnt; |
660 | } |
661 | |
662 | /** |
663 | * rpcb_getport_async - obtain the port for a given RPC service on a given host |
664 | * @task: task that is waiting for portmapper request |
665 | * |
666 | * This one can be called for an ongoing RPC request, and can be used in |
667 | * an async (rpciod) context. |
668 | */ |
669 | void rpcb_getport_async(struct rpc_task *task) |
670 | { |
671 | struct rpc_clnt *clnt; |
672 | const struct rpc_procinfo *proc; |
673 | u32 bind_version; |
674 | struct rpc_xprt *xprt; |
675 | struct rpc_clnt *rpcb_clnt; |
676 | struct rpcbind_args *map; |
677 | struct rpc_task *child; |
678 | struct sockaddr_storage addr; |
679 | struct sockaddr *sap = (struct sockaddr *)&addr; |
680 | size_t salen; |
681 | int status; |
682 | |
683 | rcu_read_lock(); |
684 | clnt = rpcb_find_transport_owner(clnt: task->tk_client); |
685 | rcu_read_unlock(); |
686 | xprt = xprt_get(xprt: task->tk_xprt); |
687 | |
688 | /* Put self on the wait queue to ensure we get notified if |
689 | * some other task is already attempting to bind the port */ |
690 | rpc_sleep_on_timeout(queue: &xprt->binding, task, |
691 | NULL, timeout: jiffies + xprt->bind_timeout); |
692 | |
693 | if (xprt_test_and_set_binding(xprt)) { |
694 | xprt_put(xprt); |
695 | return; |
696 | } |
697 | |
698 | /* Someone else may have bound if we slept */ |
699 | if (xprt_bound(xprt)) { |
700 | status = 0; |
701 | goto bailout_nofree; |
702 | } |
703 | |
704 | /* Parent transport's destination address */ |
705 | salen = rpc_peeraddr(clnt, sap, sizeof(addr)); |
706 | |
707 | /* Don't ever use rpcbind v2 for AF_INET6 requests */ |
708 | switch (sap->sa_family) { |
709 | case AF_INET: |
710 | proc = rpcb_next_version[xprt->bind_index].rpc_proc; |
711 | bind_version = rpcb_next_version[xprt->bind_index].rpc_vers; |
712 | break; |
713 | case AF_INET6: |
714 | proc = rpcb_next_version6[xprt->bind_index].rpc_proc; |
715 | bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers; |
716 | break; |
717 | default: |
718 | status = -EAFNOSUPPORT; |
719 | goto bailout_nofree; |
720 | } |
721 | if (proc == NULL) { |
722 | xprt->bind_index = 0; |
723 | status = -EPFNOSUPPORT; |
724 | goto bailout_nofree; |
725 | } |
726 | |
727 | trace_rpcb_getport(clnt, task, bind_version); |
728 | |
729 | rpcb_clnt = rpcb_create(net: xprt->xprt_net, |
730 | nodename: clnt->cl_nodename, |
731 | hostname: xprt->servername, srvaddr: sap, salen, |
732 | proto: xprt->prot, version: bind_version, |
733 | cred: clnt->cl_cred, |
734 | timeo: task->tk_client->cl_timeout); |
735 | if (IS_ERR(ptr: rpcb_clnt)) { |
736 | status = PTR_ERR(ptr: rpcb_clnt); |
737 | goto bailout_nofree; |
738 | } |
739 | |
740 | map = kzalloc(size: sizeof(struct rpcbind_args), flags: rpc_task_gfp_mask()); |
741 | if (!map) { |
742 | status = -ENOMEM; |
743 | goto bailout_release_client; |
744 | } |
745 | map->r_prog = clnt->cl_prog; |
746 | map->r_vers = clnt->cl_vers; |
747 | map->r_prot = xprt->prot; |
748 | map->r_port = 0; |
749 | map->r_xprt = xprt; |
750 | map->r_status = -EIO; |
751 | |
752 | switch (bind_version) { |
753 | case RPCBVERS_4: |
754 | case RPCBVERS_3: |
755 | map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID]; |
756 | map->r_addr = rpc_sockaddr2uaddr(sap, rpc_task_gfp_mask()); |
757 | if (!map->r_addr) { |
758 | status = -ENOMEM; |
759 | goto bailout_free_args; |
760 | } |
761 | map->r_owner = "" ; |
762 | break; |
763 | case RPCBVERS_2: |
764 | map->r_addr = NULL; |
765 | break; |
766 | default: |
767 | BUG(); |
768 | } |
769 | |
770 | child = rpcb_call_async(rpcb_clnt, map, proc); |
771 | rpc_release_client(rpcb_clnt); |
772 | if (IS_ERR(ptr: child)) { |
773 | /* rpcb_map_release() has freed the arguments */ |
774 | return; |
775 | } |
776 | |
777 | xprt->stat.bind_count++; |
778 | rpc_put_task(child); |
779 | return; |
780 | |
781 | bailout_free_args: |
782 | kfree(objp: map); |
783 | bailout_release_client: |
784 | rpc_release_client(rpcb_clnt); |
785 | bailout_nofree: |
786 | rpcb_wake_rpcbind_waiters(xprt, status); |
787 | task->tk_status = status; |
788 | xprt_put(xprt); |
789 | } |
790 | EXPORT_SYMBOL_GPL(rpcb_getport_async); |
791 | |
792 | /* |
793 | * Rpcbind child task calls this callback via tk_exit. |
794 | */ |
795 | static void rpcb_getport_done(struct rpc_task *child, void *data) |
796 | { |
797 | struct rpcbind_args *map = data; |
798 | struct rpc_xprt *xprt = map->r_xprt; |
799 | |
800 | map->r_status = child->tk_status; |
801 | |
802 | /* Garbage reply: retry with a lesser rpcbind version */ |
803 | if (map->r_status == -EIO) |
804 | map->r_status = -EPROTONOSUPPORT; |
805 | |
806 | /* rpcbind server doesn't support this rpcbind protocol version */ |
807 | if (map->r_status == -EPROTONOSUPPORT) |
808 | xprt->bind_index++; |
809 | |
810 | if (map->r_status < 0) { |
811 | /* rpcbind server not available on remote host? */ |
812 | map->r_port = 0; |
813 | |
814 | } else if (map->r_port == 0) { |
815 | /* Requested RPC service wasn't registered on remote host */ |
816 | map->r_status = -EACCES; |
817 | } else { |
818 | /* Succeeded */ |
819 | map->r_status = 0; |
820 | } |
821 | |
822 | trace_rpcb_setport(task: child, status: map->r_status, port: map->r_port); |
823 | xprt->ops->set_port(xprt, map->r_port); |
824 | if (map->r_port) |
825 | xprt_set_bound(xprt); |
826 | } |
827 | |
828 | /* |
829 | * XDR functions for rpcbind |
830 | */ |
831 | |
832 | static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, |
833 | const void *data) |
834 | { |
835 | const struct rpcbind_args *rpcb = data; |
836 | __be32 *p; |
837 | |
838 | p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2); |
839 | *p++ = cpu_to_be32(rpcb->r_prog); |
840 | *p++ = cpu_to_be32(rpcb->r_vers); |
841 | *p++ = cpu_to_be32(rpcb->r_prot); |
842 | *p = cpu_to_be32(rpcb->r_port); |
843 | } |
844 | |
845 | static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr, |
846 | void *data) |
847 | { |
848 | struct rpcbind_args *rpcb = data; |
849 | unsigned long port; |
850 | __be32 *p; |
851 | |
852 | rpcb->r_port = 0; |
853 | |
854 | p = xdr_inline_decode(xdr, nbytes: 4); |
855 | if (unlikely(p == NULL)) |
856 | return -EIO; |
857 | |
858 | port = be32_to_cpup(p); |
859 | if (unlikely(port > USHRT_MAX)) |
860 | return -EIO; |
861 | |
862 | rpcb->r_port = port; |
863 | return 0; |
864 | } |
865 | |
866 | static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr, |
867 | void *data) |
868 | { |
869 | unsigned int *boolp = data; |
870 | __be32 *p; |
871 | |
872 | p = xdr_inline_decode(xdr, nbytes: 4); |
873 | if (unlikely(p == NULL)) |
874 | return -EIO; |
875 | |
876 | *boolp = 0; |
877 | if (*p != xdr_zero) |
878 | *boolp = 1; |
879 | return 0; |
880 | } |
881 | |
882 | static void encode_rpcb_string(struct xdr_stream *xdr, const char *string, |
883 | const u32 maxstrlen) |
884 | { |
885 | __be32 *p; |
886 | u32 len; |
887 | |
888 | len = strlen(string); |
889 | WARN_ON_ONCE(len > maxstrlen); |
890 | if (len > maxstrlen) |
891 | /* truncate and hope for the best */ |
892 | len = maxstrlen; |
893 | p = xdr_reserve_space(xdr, nbytes: 4 + len); |
894 | xdr_encode_opaque(p, ptr: string, len); |
895 | } |
896 | |
897 | static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, |
898 | const void *data) |
899 | { |
900 | const struct rpcbind_args *rpcb = data; |
901 | __be32 *p; |
902 | |
903 | p = xdr_reserve_space(xdr, nbytes: (RPCB_program_sz + RPCB_version_sz) << 2); |
904 | *p++ = cpu_to_be32(rpcb->r_prog); |
905 | *p = cpu_to_be32(rpcb->r_vers); |
906 | |
907 | encode_rpcb_string(xdr, string: rpcb->r_netid, RPCBIND_MAXNETIDLEN); |
908 | encode_rpcb_string(xdr, string: rpcb->r_addr, RPCBIND_MAXUADDRLEN); |
909 | encode_rpcb_string(xdr, string: rpcb->r_owner, RPCB_MAXOWNERLEN); |
910 | } |
911 | |
912 | static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr, |
913 | void *data) |
914 | { |
915 | struct rpcbind_args *rpcb = data; |
916 | struct sockaddr_storage address; |
917 | struct sockaddr *sap = (struct sockaddr *)&address; |
918 | __be32 *p; |
919 | u32 len; |
920 | |
921 | rpcb->r_port = 0; |
922 | |
923 | p = xdr_inline_decode(xdr, nbytes: 4); |
924 | if (unlikely(p == NULL)) |
925 | goto out_fail; |
926 | len = be32_to_cpup(p); |
927 | |
928 | /* |
929 | * If the returned universal address is a null string, |
930 | * the requested RPC service was not registered. |
931 | */ |
932 | if (len == 0) |
933 | return 0; |
934 | |
935 | if (unlikely(len > RPCBIND_MAXUADDRLEN)) |
936 | goto out_fail; |
937 | |
938 | p = xdr_inline_decode(xdr, nbytes: len); |
939 | if (unlikely(p == NULL)) |
940 | goto out_fail; |
941 | |
942 | if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len, |
943 | sap, sizeof(address)) == 0) |
944 | goto out_fail; |
945 | rpcb->r_port = rpc_get_port(sap); |
946 | |
947 | return 0; |
948 | |
949 | out_fail: |
950 | return -EIO; |
951 | } |
952 | |
953 | /* |
954 | * Not all rpcbind procedures described in RFC 1833 are implemented |
955 | * since the Linux kernel RPC code requires only these. |
956 | */ |
957 | |
958 | static const struct rpc_procinfo rpcb_procedures2[] = { |
959 | [RPCBPROC_SET] = { |
960 | .p_proc = RPCBPROC_SET, |
961 | .p_encode = rpcb_enc_mapping, |
962 | .p_decode = rpcb_dec_set, |
963 | .p_arglen = RPCB_mappingargs_sz, |
964 | .p_replen = RPCB_setres_sz, |
965 | .p_statidx = RPCBPROC_SET, |
966 | .p_timer = 0, |
967 | .p_name = "SET" , |
968 | }, |
969 | [RPCBPROC_UNSET] = { |
970 | .p_proc = RPCBPROC_UNSET, |
971 | .p_encode = rpcb_enc_mapping, |
972 | .p_decode = rpcb_dec_set, |
973 | .p_arglen = RPCB_mappingargs_sz, |
974 | .p_replen = RPCB_setres_sz, |
975 | .p_statidx = RPCBPROC_UNSET, |
976 | .p_timer = 0, |
977 | .p_name = "UNSET" , |
978 | }, |
979 | [RPCBPROC_GETPORT] = { |
980 | .p_proc = RPCBPROC_GETPORT, |
981 | .p_encode = rpcb_enc_mapping, |
982 | .p_decode = rpcb_dec_getport, |
983 | .p_arglen = RPCB_mappingargs_sz, |
984 | .p_replen = RPCB_getportres_sz, |
985 | .p_statidx = RPCBPROC_GETPORT, |
986 | .p_timer = 0, |
987 | .p_name = "GETPORT" , |
988 | }, |
989 | }; |
990 | |
991 | static const struct rpc_procinfo rpcb_procedures3[] = { |
992 | [RPCBPROC_SET] = { |
993 | .p_proc = RPCBPROC_SET, |
994 | .p_encode = rpcb_enc_getaddr, |
995 | .p_decode = rpcb_dec_set, |
996 | .p_arglen = RPCB_getaddrargs_sz, |
997 | .p_replen = RPCB_setres_sz, |
998 | .p_statidx = RPCBPROC_SET, |
999 | .p_timer = 0, |
1000 | .p_name = "SET" , |
1001 | }, |
1002 | [RPCBPROC_UNSET] = { |
1003 | .p_proc = RPCBPROC_UNSET, |
1004 | .p_encode = rpcb_enc_getaddr, |
1005 | .p_decode = rpcb_dec_set, |
1006 | .p_arglen = RPCB_getaddrargs_sz, |
1007 | .p_replen = RPCB_setres_sz, |
1008 | .p_statidx = RPCBPROC_UNSET, |
1009 | .p_timer = 0, |
1010 | .p_name = "UNSET" , |
1011 | }, |
1012 | [RPCBPROC_GETADDR] = { |
1013 | .p_proc = RPCBPROC_GETADDR, |
1014 | .p_encode = rpcb_enc_getaddr, |
1015 | .p_decode = rpcb_dec_getaddr, |
1016 | .p_arglen = RPCB_getaddrargs_sz, |
1017 | .p_replen = RPCB_getaddrres_sz, |
1018 | .p_statidx = RPCBPROC_GETADDR, |
1019 | .p_timer = 0, |
1020 | .p_name = "GETADDR" , |
1021 | }, |
1022 | }; |
1023 | |
1024 | static const struct rpc_procinfo rpcb_procedures4[] = { |
1025 | [RPCBPROC_SET] = { |
1026 | .p_proc = RPCBPROC_SET, |
1027 | .p_encode = rpcb_enc_getaddr, |
1028 | .p_decode = rpcb_dec_set, |
1029 | .p_arglen = RPCB_getaddrargs_sz, |
1030 | .p_replen = RPCB_setres_sz, |
1031 | .p_statidx = RPCBPROC_SET, |
1032 | .p_timer = 0, |
1033 | .p_name = "SET" , |
1034 | }, |
1035 | [RPCBPROC_UNSET] = { |
1036 | .p_proc = RPCBPROC_UNSET, |
1037 | .p_encode = rpcb_enc_getaddr, |
1038 | .p_decode = rpcb_dec_set, |
1039 | .p_arglen = RPCB_getaddrargs_sz, |
1040 | .p_replen = RPCB_setres_sz, |
1041 | .p_statidx = RPCBPROC_UNSET, |
1042 | .p_timer = 0, |
1043 | .p_name = "UNSET" , |
1044 | }, |
1045 | [RPCBPROC_GETADDR] = { |
1046 | .p_proc = RPCBPROC_GETADDR, |
1047 | .p_encode = rpcb_enc_getaddr, |
1048 | .p_decode = rpcb_dec_getaddr, |
1049 | .p_arglen = RPCB_getaddrargs_sz, |
1050 | .p_replen = RPCB_getaddrres_sz, |
1051 | .p_statidx = RPCBPROC_GETADDR, |
1052 | .p_timer = 0, |
1053 | .p_name = "GETADDR" , |
1054 | }, |
1055 | }; |
1056 | |
1057 | static const struct rpcb_info rpcb_next_version[] = { |
1058 | { |
1059 | .rpc_vers = RPCBVERS_2, |
1060 | .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT], |
1061 | }, |
1062 | { |
1063 | .rpc_proc = NULL, |
1064 | }, |
1065 | }; |
1066 | |
1067 | static const struct rpcb_info rpcb_next_version6[] = { |
1068 | { |
1069 | .rpc_vers = RPCBVERS_4, |
1070 | .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR], |
1071 | }, |
1072 | { |
1073 | .rpc_vers = RPCBVERS_3, |
1074 | .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR], |
1075 | }, |
1076 | { |
1077 | .rpc_proc = NULL, |
1078 | }, |
1079 | }; |
1080 | |
1081 | static unsigned int rpcb_version2_counts[ARRAY_SIZE(rpcb_procedures2)]; |
1082 | static const struct rpc_version rpcb_version2 = { |
1083 | .number = RPCBVERS_2, |
1084 | .nrprocs = ARRAY_SIZE(rpcb_procedures2), |
1085 | .procs = rpcb_procedures2, |
1086 | .counts = rpcb_version2_counts, |
1087 | }; |
1088 | |
1089 | static unsigned int rpcb_version3_counts[ARRAY_SIZE(rpcb_procedures3)]; |
1090 | static const struct rpc_version rpcb_version3 = { |
1091 | .number = RPCBVERS_3, |
1092 | .nrprocs = ARRAY_SIZE(rpcb_procedures3), |
1093 | .procs = rpcb_procedures3, |
1094 | .counts = rpcb_version3_counts, |
1095 | }; |
1096 | |
1097 | static unsigned int rpcb_version4_counts[ARRAY_SIZE(rpcb_procedures4)]; |
1098 | static const struct rpc_version rpcb_version4 = { |
1099 | .number = RPCBVERS_4, |
1100 | .nrprocs = ARRAY_SIZE(rpcb_procedures4), |
1101 | .procs = rpcb_procedures4, |
1102 | .counts = rpcb_version4_counts, |
1103 | }; |
1104 | |
1105 | static const struct rpc_version *rpcb_version[] = { |
1106 | NULL, |
1107 | NULL, |
1108 | &rpcb_version2, |
1109 | &rpcb_version3, |
1110 | &rpcb_version4 |
1111 | }; |
1112 | |
1113 | static struct rpc_stat rpcb_stats; |
1114 | |
1115 | static const struct rpc_program rpcb_program = { |
1116 | .name = "rpcbind" , |
1117 | .number = RPCBIND_PROGRAM, |
1118 | .nrvers = ARRAY_SIZE(rpcb_version), |
1119 | .version = rpcb_version, |
1120 | .stats = &rpcb_stats, |
1121 | }; |
1122 | |