blob: 9a55797a1cd420ac6b5fa051ebfc9d5780f2ccca [file] [log] [blame]
Chuck Lever2b061f92010-12-14 14:55:40 +00001/*
2 * linux/fs/lockd/clntxdr.c
3 *
4 * XDR functions to encode/decode NLM version 3 RPC arguments and results.
5 * NLM version 3 is backwards compatible with NLM versions 1 and 2.
6 *
7 * NLM client-side only.
8 *
9 * Copyright (C) 2010, Oracle. All rights reserved.
10 */
11
12#include <linux/types.h>
13#include <linux/sunrpc/xdr.h>
14#include <linux/sunrpc/clnt.h>
15#include <linux/sunrpc/stats.h>
16#include <linux/lockd/lockd.h>
17
18#define NLMDBG_FACILITY NLMDBG_XDR
19
20#if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
21# error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
22#endif
23
24/*
25 * Declare the space requirements for NLM arguments and replies as
26 * number of 32bit-words
27 */
28#define NLM_cookie_sz (1+(NLM_MAXCOOKIELEN>>2))
29#define NLM_caller_sz (1+(NLMCLNT_OHSIZE>>2))
30#define NLM_owner_sz (1+(NLMCLNT_OHSIZE>>2))
31#define NLM_fhandle_sz (1+(NFS2_FHSIZE>>2))
32#define NLM_lock_sz (3+NLM_caller_sz+NLM_owner_sz+NLM_fhandle_sz)
33#define NLM_holder_sz (4+NLM_owner_sz)
34
35#define NLM_testargs_sz (NLM_cookie_sz+1+NLM_lock_sz)
36#define NLM_lockargs_sz (NLM_cookie_sz+4+NLM_lock_sz)
37#define NLM_cancargs_sz (NLM_cookie_sz+2+NLM_lock_sz)
38#define NLM_unlockargs_sz (NLM_cookie_sz+NLM_lock_sz)
39
40#define NLM_testres_sz (NLM_cookie_sz+1+NLM_holder_sz)
41#define NLM_res_sz (NLM_cookie_sz+1)
42#define NLM_norep_sz (0)
43
44
45static s32 loff_t_to_s32(loff_t offset)
46{
47 s32 res;
48
49 if (offset >= NLM_OFFSET_MAX)
50 res = NLM_OFFSET_MAX;
51 else if (offset <= -NLM_OFFSET_MAX)
52 res = -NLM_OFFSET_MAX;
53 else
54 res = offset;
55 return res;
56}
57
58static void nlm_compute_offsets(const struct nlm_lock *lock,
59 u32 *l_offset, u32 *l_len)
60{
61 const struct file_lock *fl = &lock->fl;
62
Chuck Lever2b061f92010-12-14 14:55:40 +000063 *l_offset = loff_t_to_s32(fl->fl_start);
64 if (fl->fl_end == OFFSET_MAX)
65 *l_len = 0;
66 else
67 *l_len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
68}
69
70/*
71 * Handle decode buffer overflows out-of-line.
72 */
73static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
74{
75 dprintk("lockd: %s prematurely hit the end of our receive buffer. "
76 "Remaining buffer length is %tu words.\n",
77 func, xdr->end - xdr->p);
78}
79
80
81/*
82 * Encode/decode NLMv3 basic data types
83 *
84 * Basic NLMv3 data types are not defined in an IETF standards
85 * document. X/Open has a description of these data types that
86 * is useful. See Chapter 10 of "Protocols for Interworking:
87 * XNFS, Version 3W".
88 *
89 * Not all basic data types have their own encoding and decoding
90 * functions. For run-time efficiency, some data types are encoded
91 * or decoded inline.
92 */
93
94static void encode_bool(struct xdr_stream *xdr, const int value)
95{
96 __be32 *p;
97
98 p = xdr_reserve_space(xdr, 4);
99 *p = value ? xdr_one : xdr_zero;
100}
101
102static void encode_int32(struct xdr_stream *xdr, const s32 value)
103{
104 __be32 *p;
105
106 p = xdr_reserve_space(xdr, 4);
107 *p = cpu_to_be32(value);
108}
109
110/*
111 * typedef opaque netobj<MAXNETOBJ_SZ>
112 */
113static void encode_netobj(struct xdr_stream *xdr,
114 const u8 *data, const unsigned int length)
115{
116 __be32 *p;
117
Chuck Lever2b061f92010-12-14 14:55:40 +0000118 p = xdr_reserve_space(xdr, 4 + length);
119 xdr_encode_opaque(p, data, length);
120}
121
122static int decode_netobj(struct xdr_stream *xdr,
123 struct xdr_netobj *obj)
124{
125 u32 length;
126 __be32 *p;
127
128 p = xdr_inline_decode(xdr, 4);
129 if (unlikely(p == NULL))
130 goto out_overflow;
131 length = be32_to_cpup(p++);
132 if (unlikely(length > XDR_MAX_NETOBJ))
133 goto out_size;
134 obj->len = length;
135 obj->data = (u8 *)p;
136 return 0;
137out_size:
138 dprintk("NFS: returned netobj was too long: %u\n", length);
139 return -EIO;
140out_overflow:
141 print_overflow_msg(__func__, xdr);
142 return -EIO;
143}
144
145/*
146 * netobj cookie;
147 */
148static void encode_cookie(struct xdr_stream *xdr,
149 const struct nlm_cookie *cookie)
150{
Chuck Lever2b061f92010-12-14 14:55:40 +0000151 encode_netobj(xdr, (u8 *)&cookie->data, cookie->len);
152}
153
154static int decode_cookie(struct xdr_stream *xdr,
155 struct nlm_cookie *cookie)
156{
157 u32 length;
158 __be32 *p;
159
160 p = xdr_inline_decode(xdr, 4);
161 if (unlikely(p == NULL))
162 goto out_overflow;
163 length = be32_to_cpup(p++);
164 /* apparently HPUX can return empty cookies */
165 if (length == 0)
166 goto out_hpux;
167 if (length > NLM_MAXCOOKIELEN)
168 goto out_size;
169 p = xdr_inline_decode(xdr, length);
170 if (unlikely(p == NULL))
171 goto out_overflow;
172 cookie->len = length;
173 memcpy(cookie->data, p, length);
174 return 0;
175out_hpux:
176 cookie->len = 4;
177 memset(cookie->data, 0, 4);
178 return 0;
179out_size:
180 dprintk("NFS: returned cookie was too long: %u\n", length);
181 return -EIO;
182out_overflow:
183 print_overflow_msg(__func__, xdr);
184 return -EIO;
185}
186
187/*
188 * netobj fh;
189 */
190static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh)
191{
Chuck Lever2b061f92010-12-14 14:55:40 +0000192 encode_netobj(xdr, (u8 *)&fh->data, NFS2_FHSIZE);
193}
194
195/*
196 * enum nlm_stats {
197 * LCK_GRANTED = 0,
198 * LCK_DENIED = 1,
199 * LCK_DENIED_NOLOCKS = 2,
200 * LCK_BLOCKED = 3,
201 * LCK_DENIED_GRACE_PERIOD = 4
202 * };
203 *
204 *
205 * struct nlm_stat {
206 * nlm_stats stat;
207 * };
208 *
209 * NB: we don't swap bytes for the NLM status values. The upper
210 * layers deal directly with the status value in network byte
211 * order.
212 */
213
214static void encode_nlm_stat(struct xdr_stream *xdr,
215 const __be32 stat)
216{
217 __be32 *p;
218
Trond Myklebustcd0b16c2012-10-13 00:30:28 -0400219 WARN_ON_ONCE(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD);
Chuck Lever2b061f92010-12-14 14:55:40 +0000220 p = xdr_reserve_space(xdr, 4);
221 *p = stat;
222}
223
224static int decode_nlm_stat(struct xdr_stream *xdr,
225 __be32 *stat)
226{
227 __be32 *p;
228
229 p = xdr_inline_decode(xdr, 4);
230 if (unlikely(p == NULL))
231 goto out_overflow;
Al Viroe8474692012-04-13 13:49:47 -0400232 if (unlikely(ntohl(*p) > ntohl(nlm_lck_denied_grace_period)))
Chuck Lever2b061f92010-12-14 14:55:40 +0000233 goto out_enum;
234 *stat = *p;
235 return 0;
236out_enum:
237 dprintk("%s: server returned invalid nlm_stats value: %u\n",
238 __func__, be32_to_cpup(p));
239 return -EIO;
240out_overflow:
241 print_overflow_msg(__func__, xdr);
242 return -EIO;
243}
244
245/*
246 * struct nlm_holder {
247 * bool exclusive;
248 * int uppid;
249 * netobj oh;
250 * unsigned l_offset;
251 * unsigned l_len;
252 * };
253 */
254static void encode_nlm_holder(struct xdr_stream *xdr,
255 const struct nlm_res *result)
256{
257 const struct nlm_lock *lock = &result->lock;
258 u32 l_offset, l_len;
259 __be32 *p;
260
261 encode_bool(xdr, lock->fl.fl_type == F_RDLCK);
262 encode_int32(xdr, lock->svid);
263 encode_netobj(xdr, lock->oh.data, lock->oh.len);
264
265 p = xdr_reserve_space(xdr, 4 + 4);
266 nlm_compute_offsets(lock, &l_offset, &l_len);
267 *p++ = cpu_to_be32(l_offset);
268 *p = cpu_to_be32(l_len);
269}
270
271static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result)
272{
273 struct nlm_lock *lock = &result->lock;
274 struct file_lock *fl = &lock->fl;
275 u32 exclusive, l_offset, l_len;
276 int error;
277 __be32 *p;
278 s32 end;
279
280 memset(lock, 0, sizeof(*lock));
281 locks_init_lock(fl);
282
283 p = xdr_inline_decode(xdr, 4 + 4);
284 if (unlikely(p == NULL))
285 goto out_overflow;
286 exclusive = be32_to_cpup(p++);
287 lock->svid = be32_to_cpup(p);
288 fl->fl_pid = (pid_t)lock->svid;
289
290 error = decode_netobj(xdr, &lock->oh);
291 if (unlikely(error))
292 goto out;
293
294 p = xdr_inline_decode(xdr, 4 + 4);
295 if (unlikely(p == NULL))
296 goto out_overflow;
297
298 fl->fl_flags = FL_POSIX;
299 fl->fl_type = exclusive != 0 ? F_WRLCK : F_RDLCK;
300 l_offset = be32_to_cpup(p++);
301 l_len = be32_to_cpup(p);
302 end = l_offset + l_len - 1;
303
304 fl->fl_start = (loff_t)l_offset;
305 if (l_len == 0 || end < 0)
306 fl->fl_end = OFFSET_MAX;
307 else
308 fl->fl_end = (loff_t)end;
309 error = 0;
310out:
311 return error;
312out_overflow:
313 print_overflow_msg(__func__, xdr);
314 return -EIO;
315}
316
317/*
318 * string caller_name<LM_MAXSTRLEN>;
319 */
320static void encode_caller_name(struct xdr_stream *xdr, const char *name)
321{
322 /* NB: client-side does not set lock->len */
323 u32 length = strlen(name);
324 __be32 *p;
325
Chuck Lever2b061f92010-12-14 14:55:40 +0000326 p = xdr_reserve_space(xdr, 4 + length);
327 xdr_encode_opaque(p, name, length);
328}
329
330/*
331 * struct nlm_lock {
332 * string caller_name<LM_MAXSTRLEN>;
333 * netobj fh;
334 * netobj oh;
335 * int uppid;
336 * unsigned l_offset;
337 * unsigned l_len;
338 * };
339 */
340static void encode_nlm_lock(struct xdr_stream *xdr,
341 const struct nlm_lock *lock)
342{
343 u32 l_offset, l_len;
344 __be32 *p;
345
346 encode_caller_name(xdr, lock->caller);
347 encode_fh(xdr, &lock->fh);
348 encode_netobj(xdr, lock->oh.data, lock->oh.len);
349
350 p = xdr_reserve_space(xdr, 4 + 4 + 4);
351 *p++ = cpu_to_be32(lock->svid);
352
353 nlm_compute_offsets(lock, &l_offset, &l_len);
354 *p++ = cpu_to_be32(l_offset);
355 *p = cpu_to_be32(l_len);
356}
357
358
359/*
360 * NLMv3 XDR encode functions
361 *
362 * NLMv3 argument types are defined in Chapter 10 of The Open Group's
363 * "Protocols for Interworking: XNFS, Version 3W".
364 */
365
366/*
367 * struct nlm_testargs {
368 * netobj cookie;
369 * bool exclusive;
370 * struct nlm_lock alock;
371 * };
372 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000373static void nlm_xdr_enc_testargs(struct rpc_rqst *req,
374 struct xdr_stream *xdr,
375 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000376{
377 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000378
Chuck Lever9f06c712010-12-14 14:59:18 +0000379 encode_cookie(xdr, &args->cookie);
380 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
381 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000382}
383
384/*
385 * struct nlm_lockargs {
386 * netobj cookie;
387 * bool block;
388 * bool exclusive;
389 * struct nlm_lock alock;
390 * bool reclaim;
391 * int state;
392 * };
393 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000394static void nlm_xdr_enc_lockargs(struct rpc_rqst *req,
395 struct xdr_stream *xdr,
396 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000397{
398 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000399
Chuck Lever9f06c712010-12-14 14:59:18 +0000400 encode_cookie(xdr, &args->cookie);
401 encode_bool(xdr, args->block);
402 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
403 encode_nlm_lock(xdr, lock);
404 encode_bool(xdr, args->reclaim);
405 encode_int32(xdr, args->state);
Chuck Lever2b061f92010-12-14 14:55:40 +0000406}
407
408/*
409 * struct nlm_cancargs {
410 * netobj cookie;
411 * bool block;
412 * bool exclusive;
413 * struct nlm_lock alock;
414 * };
415 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000416static void nlm_xdr_enc_cancargs(struct rpc_rqst *req,
417 struct xdr_stream *xdr,
418 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000419{
420 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000421
Chuck Lever9f06c712010-12-14 14:59:18 +0000422 encode_cookie(xdr, &args->cookie);
423 encode_bool(xdr, args->block);
424 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
425 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000426}
427
428/*
429 * struct nlm_unlockargs {
430 * netobj cookie;
431 * struct nlm_lock alock;
432 * };
433 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000434static void nlm_xdr_enc_unlockargs(struct rpc_rqst *req,
435 struct xdr_stream *xdr,
436 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000437{
438 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000439
Chuck Lever9f06c712010-12-14 14:59:18 +0000440 encode_cookie(xdr, &args->cookie);
441 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000442}
443
444/*
445 * struct nlm_res {
446 * netobj cookie;
447 * nlm_stat stat;
448 * };
449 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000450static void nlm_xdr_enc_res(struct rpc_rqst *req,
451 struct xdr_stream *xdr,
452 const struct nlm_res *result)
Chuck Lever2b061f92010-12-14 14:55:40 +0000453{
Chuck Lever9f06c712010-12-14 14:59:18 +0000454 encode_cookie(xdr, &result->cookie);
455 encode_nlm_stat(xdr, result->status);
Chuck Lever2b061f92010-12-14 14:55:40 +0000456}
457
458/*
459 * union nlm_testrply switch (nlm_stats stat) {
460 * case LCK_DENIED:
461 * struct nlm_holder holder;
462 * default:
463 * void;
464 * };
465 *
466 * struct nlm_testres {
467 * netobj cookie;
468 * nlm_testrply test_stat;
469 * };
470 */
471static void encode_nlm_testrply(struct xdr_stream *xdr,
472 const struct nlm_res *result)
473{
474 if (result->status == nlm_lck_denied)
475 encode_nlm_holder(xdr, result);
476}
477
Chuck Lever9f06c712010-12-14 14:59:18 +0000478static void nlm_xdr_enc_testres(struct rpc_rqst *req,
479 struct xdr_stream *xdr,
480 const struct nlm_res *result)
Chuck Lever2b061f92010-12-14 14:55:40 +0000481{
Chuck Lever9f06c712010-12-14 14:59:18 +0000482 encode_cookie(xdr, &result->cookie);
483 encode_nlm_stat(xdr, result->status);
484 encode_nlm_testrply(xdr, result);
Chuck Lever2b061f92010-12-14 14:55:40 +0000485}
486
487
488/*
489 * NLMv3 XDR decode functions
490 *
491 * NLMv3 result types are defined in Chapter 10 of The Open Group's
492 * "Protocols for Interworking: XNFS, Version 3W".
493 */
494
495/*
496 * union nlm_testrply switch (nlm_stats stat) {
497 * case LCK_DENIED:
498 * struct nlm_holder holder;
499 * default:
500 * void;
501 * };
502 *
503 * struct nlm_testres {
504 * netobj cookie;
505 * nlm_testrply test_stat;
506 * };
507 */
508static int decode_nlm_testrply(struct xdr_stream *xdr,
509 struct nlm_res *result)
510{
511 int error;
512
513 error = decode_nlm_stat(xdr, &result->status);
514 if (unlikely(error))
515 goto out;
516 if (result->status == nlm_lck_denied)
517 error = decode_nlm_holder(xdr, result);
518out:
519 return error;
520}
521
Chuck Leverbf269552010-12-14 14:59:29 +0000522static int nlm_xdr_dec_testres(struct rpc_rqst *req,
523 struct xdr_stream *xdr,
Chuck Lever2b061f92010-12-14 14:55:40 +0000524 struct nlm_res *result)
525{
Chuck Lever2b061f92010-12-14 14:55:40 +0000526 int error;
527
Chuck Leverbf269552010-12-14 14:59:29 +0000528 error = decode_cookie(xdr, &result->cookie);
Chuck Lever2b061f92010-12-14 14:55:40 +0000529 if (unlikely(error))
530 goto out;
Chuck Leverbf269552010-12-14 14:59:29 +0000531 error = decode_nlm_testrply(xdr, result);
Chuck Lever2b061f92010-12-14 14:55:40 +0000532out:
533 return error;
534}
535
536/*
537 * struct nlm_res {
538 * netobj cookie;
539 * nlm_stat stat;
540 * };
541 */
Chuck Leverbf269552010-12-14 14:59:29 +0000542static int nlm_xdr_dec_res(struct rpc_rqst *req,
543 struct xdr_stream *xdr,
Chuck Lever2b061f92010-12-14 14:55:40 +0000544 struct nlm_res *result)
545{
Chuck Lever2b061f92010-12-14 14:55:40 +0000546 int error;
547
Chuck Leverbf269552010-12-14 14:59:29 +0000548 error = decode_cookie(xdr, &result->cookie);
Chuck Lever2b061f92010-12-14 14:55:40 +0000549 if (unlikely(error))
550 goto out;
Chuck Leverbf269552010-12-14 14:59:29 +0000551 error = decode_nlm_stat(xdr, &result->status);
Chuck Lever2b061f92010-12-14 14:55:40 +0000552out:
553 return error;
554}
555
556
557/*
558 * For NLM, a void procedure really returns nothing
559 */
560#define nlm_xdr_dec_norep NULL
561
562#define PROC(proc, argtype, restype) \
563[NLMPROC_##proc] = { \
564 .p_proc = NLMPROC_##proc, \
Chuck Lever9f06c712010-12-14 14:59:18 +0000565 .p_encode = (kxdreproc_t)nlm_xdr_enc_##argtype, \
Chuck Leverbf269552010-12-14 14:59:29 +0000566 .p_decode = (kxdrdproc_t)nlm_xdr_dec_##restype, \
Chuck Lever2b061f92010-12-14 14:55:40 +0000567 .p_arglen = NLM_##argtype##_sz, \
568 .p_replen = NLM_##restype##_sz, \
569 .p_statidx = NLMPROC_##proc, \
570 .p_name = #proc, \
571 }
572
573static struct rpc_procinfo nlm_procedures[] = {
574 PROC(TEST, testargs, testres),
575 PROC(LOCK, lockargs, res),
576 PROC(CANCEL, cancargs, res),
577 PROC(UNLOCK, unlockargs, res),
578 PROC(GRANTED, testargs, res),
579 PROC(TEST_MSG, testargs, norep),
580 PROC(LOCK_MSG, lockargs, norep),
581 PROC(CANCEL_MSG, cancargs, norep),
582 PROC(UNLOCK_MSG, unlockargs, norep),
583 PROC(GRANTED_MSG, testargs, norep),
584 PROC(TEST_RES, testres, norep),
585 PROC(LOCK_RES, res, norep),
586 PROC(CANCEL_RES, res, norep),
587 PROC(UNLOCK_RES, res, norep),
588 PROC(GRANTED_RES, res, norep),
589};
590
Trond Myklebusta613fa12012-01-20 13:53:56 -0500591static const struct rpc_version nlm_version1 = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000592 .number = 1,
593 .nrprocs = ARRAY_SIZE(nlm_procedures),
594 .procs = nlm_procedures,
595};
596
Trond Myklebusta613fa12012-01-20 13:53:56 -0500597static const struct rpc_version nlm_version3 = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000598 .number = 3,
599 .nrprocs = ARRAY_SIZE(nlm_procedures),
600 .procs = nlm_procedures,
601};
602
Trond Myklebusta613fa12012-01-20 13:53:56 -0500603static const struct rpc_version *nlm_versions[] = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000604 [1] = &nlm_version1,
605 [3] = &nlm_version3,
606#ifdef CONFIG_LOCKD_V4
607 [4] = &nlm_version4,
608#endif
609};
610
611static struct rpc_stat nlm_rpc_stats;
612
Trond Myklebusta613fa12012-01-20 13:53:56 -0500613const struct rpc_program nlm_program = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000614 .name = "lockd",
615 .number = NLM_PROGRAM,
616 .nrvers = ARRAY_SIZE(nlm_versions),
617 .version = nlm_versions,
618 .stats = &nlm_rpc_stats,
619};