blob: 3d35e3e80c1ccfac1367647b6ac417ba3f5bd1b2 [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
63 BUG_ON(fl->fl_start > NLM_OFFSET_MAX);
64 BUG_ON(fl->fl_end > NLM_OFFSET_MAX &&
65 fl->fl_end != OFFSET_MAX);
66
67 *l_offset = loff_t_to_s32(fl->fl_start);
68 if (fl->fl_end == OFFSET_MAX)
69 *l_len = 0;
70 else
71 *l_len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
72}
73
74/*
75 * Handle decode buffer overflows out-of-line.
76 */
77static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
78{
79 dprintk("lockd: %s prematurely hit the end of our receive buffer. "
80 "Remaining buffer length is %tu words.\n",
81 func, xdr->end - xdr->p);
82}
83
84
85/*
86 * Encode/decode NLMv3 basic data types
87 *
88 * Basic NLMv3 data types are not defined in an IETF standards
89 * document. X/Open has a description of these data types that
90 * is useful. See Chapter 10 of "Protocols for Interworking:
91 * XNFS, Version 3W".
92 *
93 * Not all basic data types have their own encoding and decoding
94 * functions. For run-time efficiency, some data types are encoded
95 * or decoded inline.
96 */
97
98static void encode_bool(struct xdr_stream *xdr, const int value)
99{
100 __be32 *p;
101
102 p = xdr_reserve_space(xdr, 4);
103 *p = value ? xdr_one : xdr_zero;
104}
105
106static void encode_int32(struct xdr_stream *xdr, const s32 value)
107{
108 __be32 *p;
109
110 p = xdr_reserve_space(xdr, 4);
111 *p = cpu_to_be32(value);
112}
113
114/*
115 * typedef opaque netobj<MAXNETOBJ_SZ>
116 */
117static void encode_netobj(struct xdr_stream *xdr,
118 const u8 *data, const unsigned int length)
119{
120 __be32 *p;
121
122 BUG_ON(length > XDR_MAX_NETOBJ);
123 p = xdr_reserve_space(xdr, 4 + length);
124 xdr_encode_opaque(p, data, length);
125}
126
127static int decode_netobj(struct xdr_stream *xdr,
128 struct xdr_netobj *obj)
129{
130 u32 length;
131 __be32 *p;
132
133 p = xdr_inline_decode(xdr, 4);
134 if (unlikely(p == NULL))
135 goto out_overflow;
136 length = be32_to_cpup(p++);
137 if (unlikely(length > XDR_MAX_NETOBJ))
138 goto out_size;
139 obj->len = length;
140 obj->data = (u8 *)p;
141 return 0;
142out_size:
143 dprintk("NFS: returned netobj was too long: %u\n", length);
144 return -EIO;
145out_overflow:
146 print_overflow_msg(__func__, xdr);
147 return -EIO;
148}
149
150/*
151 * netobj cookie;
152 */
153static void encode_cookie(struct xdr_stream *xdr,
154 const struct nlm_cookie *cookie)
155{
156 BUG_ON(cookie->len > NLM_MAXCOOKIELEN);
157 encode_netobj(xdr, (u8 *)&cookie->data, cookie->len);
158}
159
160static int decode_cookie(struct xdr_stream *xdr,
161 struct nlm_cookie *cookie)
162{
163 u32 length;
164 __be32 *p;
165
166 p = xdr_inline_decode(xdr, 4);
167 if (unlikely(p == NULL))
168 goto out_overflow;
169 length = be32_to_cpup(p++);
170 /* apparently HPUX can return empty cookies */
171 if (length == 0)
172 goto out_hpux;
173 if (length > NLM_MAXCOOKIELEN)
174 goto out_size;
175 p = xdr_inline_decode(xdr, length);
176 if (unlikely(p == NULL))
177 goto out_overflow;
178 cookie->len = length;
179 memcpy(cookie->data, p, length);
180 return 0;
181out_hpux:
182 cookie->len = 4;
183 memset(cookie->data, 0, 4);
184 return 0;
185out_size:
186 dprintk("NFS: returned cookie was too long: %u\n", length);
187 return -EIO;
188out_overflow:
189 print_overflow_msg(__func__, xdr);
190 return -EIO;
191}
192
193/*
194 * netobj fh;
195 */
196static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh)
197{
198 BUG_ON(fh->size != NFS2_FHSIZE);
199 encode_netobj(xdr, (u8 *)&fh->data, NFS2_FHSIZE);
200}
201
202/*
203 * enum nlm_stats {
204 * LCK_GRANTED = 0,
205 * LCK_DENIED = 1,
206 * LCK_DENIED_NOLOCKS = 2,
207 * LCK_BLOCKED = 3,
208 * LCK_DENIED_GRACE_PERIOD = 4
209 * };
210 *
211 *
212 * struct nlm_stat {
213 * nlm_stats stat;
214 * };
215 *
216 * NB: we don't swap bytes for the NLM status values. The upper
217 * layers deal directly with the status value in network byte
218 * order.
219 */
220
221static void encode_nlm_stat(struct xdr_stream *xdr,
222 const __be32 stat)
223{
224 __be32 *p;
225
226 BUG_ON(be32_to_cpu(stat) > NLM_LCK_DENIED_GRACE_PERIOD);
227 p = xdr_reserve_space(xdr, 4);
228 *p = stat;
229}
230
231static int decode_nlm_stat(struct xdr_stream *xdr,
232 __be32 *stat)
233{
234 __be32 *p;
235
236 p = xdr_inline_decode(xdr, 4);
237 if (unlikely(p == NULL))
238 goto out_overflow;
239 if (unlikely(*p > nlm_lck_denied_grace_period))
240 goto out_enum;
241 *stat = *p;
242 return 0;
243out_enum:
244 dprintk("%s: server returned invalid nlm_stats value: %u\n",
245 __func__, be32_to_cpup(p));
246 return -EIO;
247out_overflow:
248 print_overflow_msg(__func__, xdr);
249 return -EIO;
250}
251
252/*
253 * struct nlm_holder {
254 * bool exclusive;
255 * int uppid;
256 * netobj oh;
257 * unsigned l_offset;
258 * unsigned l_len;
259 * };
260 */
261static void encode_nlm_holder(struct xdr_stream *xdr,
262 const struct nlm_res *result)
263{
264 const struct nlm_lock *lock = &result->lock;
265 u32 l_offset, l_len;
266 __be32 *p;
267
268 encode_bool(xdr, lock->fl.fl_type == F_RDLCK);
269 encode_int32(xdr, lock->svid);
270 encode_netobj(xdr, lock->oh.data, lock->oh.len);
271
272 p = xdr_reserve_space(xdr, 4 + 4);
273 nlm_compute_offsets(lock, &l_offset, &l_len);
274 *p++ = cpu_to_be32(l_offset);
275 *p = cpu_to_be32(l_len);
276}
277
278static int decode_nlm_holder(struct xdr_stream *xdr, struct nlm_res *result)
279{
280 struct nlm_lock *lock = &result->lock;
281 struct file_lock *fl = &lock->fl;
282 u32 exclusive, l_offset, l_len;
283 int error;
284 __be32 *p;
285 s32 end;
286
287 memset(lock, 0, sizeof(*lock));
288 locks_init_lock(fl);
289
290 p = xdr_inline_decode(xdr, 4 + 4);
291 if (unlikely(p == NULL))
292 goto out_overflow;
293 exclusive = be32_to_cpup(p++);
294 lock->svid = be32_to_cpup(p);
295 fl->fl_pid = (pid_t)lock->svid;
296
297 error = decode_netobj(xdr, &lock->oh);
298 if (unlikely(error))
299 goto out;
300
301 p = xdr_inline_decode(xdr, 4 + 4);
302 if (unlikely(p == NULL))
303 goto out_overflow;
304
305 fl->fl_flags = FL_POSIX;
306 fl->fl_type = exclusive != 0 ? F_WRLCK : F_RDLCK;
307 l_offset = be32_to_cpup(p++);
308 l_len = be32_to_cpup(p);
309 end = l_offset + l_len - 1;
310
311 fl->fl_start = (loff_t)l_offset;
312 if (l_len == 0 || end < 0)
313 fl->fl_end = OFFSET_MAX;
314 else
315 fl->fl_end = (loff_t)end;
316 error = 0;
317out:
318 return error;
319out_overflow:
320 print_overflow_msg(__func__, xdr);
321 return -EIO;
322}
323
324/*
325 * string caller_name<LM_MAXSTRLEN>;
326 */
327static void encode_caller_name(struct xdr_stream *xdr, const char *name)
328{
329 /* NB: client-side does not set lock->len */
330 u32 length = strlen(name);
331 __be32 *p;
332
333 BUG_ON(length > NLM_MAXSTRLEN);
334 p = xdr_reserve_space(xdr, 4 + length);
335 xdr_encode_opaque(p, name, length);
336}
337
338/*
339 * struct nlm_lock {
340 * string caller_name<LM_MAXSTRLEN>;
341 * netobj fh;
342 * netobj oh;
343 * int uppid;
344 * unsigned l_offset;
345 * unsigned l_len;
346 * };
347 */
348static void encode_nlm_lock(struct xdr_stream *xdr,
349 const struct nlm_lock *lock)
350{
351 u32 l_offset, l_len;
352 __be32 *p;
353
354 encode_caller_name(xdr, lock->caller);
355 encode_fh(xdr, &lock->fh);
356 encode_netobj(xdr, lock->oh.data, lock->oh.len);
357
358 p = xdr_reserve_space(xdr, 4 + 4 + 4);
359 *p++ = cpu_to_be32(lock->svid);
360
361 nlm_compute_offsets(lock, &l_offset, &l_len);
362 *p++ = cpu_to_be32(l_offset);
363 *p = cpu_to_be32(l_len);
364}
365
366
367/*
368 * NLMv3 XDR encode functions
369 *
370 * NLMv3 argument types are defined in Chapter 10 of The Open Group's
371 * "Protocols for Interworking: XNFS, Version 3W".
372 */
373
374/*
375 * struct nlm_testargs {
376 * netobj cookie;
377 * bool exclusive;
378 * struct nlm_lock alock;
379 * };
380 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000381static void nlm_xdr_enc_testargs(struct rpc_rqst *req,
382 struct xdr_stream *xdr,
383 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000384{
385 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000386
Chuck Lever9f06c712010-12-14 14:59:18 +0000387 encode_cookie(xdr, &args->cookie);
388 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
389 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000390}
391
392/*
393 * struct nlm_lockargs {
394 * netobj cookie;
395 * bool block;
396 * bool exclusive;
397 * struct nlm_lock alock;
398 * bool reclaim;
399 * int state;
400 * };
401 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000402static void nlm_xdr_enc_lockargs(struct rpc_rqst *req,
403 struct xdr_stream *xdr,
404 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000405{
406 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000407
Chuck Lever9f06c712010-12-14 14:59:18 +0000408 encode_cookie(xdr, &args->cookie);
409 encode_bool(xdr, args->block);
410 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
411 encode_nlm_lock(xdr, lock);
412 encode_bool(xdr, args->reclaim);
413 encode_int32(xdr, args->state);
Chuck Lever2b061f92010-12-14 14:55:40 +0000414}
415
416/*
417 * struct nlm_cancargs {
418 * netobj cookie;
419 * bool block;
420 * bool exclusive;
421 * struct nlm_lock alock;
422 * };
423 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000424static void nlm_xdr_enc_cancargs(struct rpc_rqst *req,
425 struct xdr_stream *xdr,
426 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000427{
428 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000429
Chuck Lever9f06c712010-12-14 14:59:18 +0000430 encode_cookie(xdr, &args->cookie);
431 encode_bool(xdr, args->block);
432 encode_bool(xdr, lock->fl.fl_type == F_WRLCK);
433 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000434}
435
436/*
437 * struct nlm_unlockargs {
438 * netobj cookie;
439 * struct nlm_lock alock;
440 * };
441 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000442static void nlm_xdr_enc_unlockargs(struct rpc_rqst *req,
443 struct xdr_stream *xdr,
444 const struct nlm_args *args)
Chuck Lever2b061f92010-12-14 14:55:40 +0000445{
446 const struct nlm_lock *lock = &args->lock;
Chuck Lever2b061f92010-12-14 14:55:40 +0000447
Chuck Lever9f06c712010-12-14 14:59:18 +0000448 encode_cookie(xdr, &args->cookie);
449 encode_nlm_lock(xdr, lock);
Chuck Lever2b061f92010-12-14 14:55:40 +0000450}
451
452/*
453 * struct nlm_res {
454 * netobj cookie;
455 * nlm_stat stat;
456 * };
457 */
Chuck Lever9f06c712010-12-14 14:59:18 +0000458static void nlm_xdr_enc_res(struct rpc_rqst *req,
459 struct xdr_stream *xdr,
460 const struct nlm_res *result)
Chuck Lever2b061f92010-12-14 14:55:40 +0000461{
Chuck Lever9f06c712010-12-14 14:59:18 +0000462 encode_cookie(xdr, &result->cookie);
463 encode_nlm_stat(xdr, result->status);
Chuck Lever2b061f92010-12-14 14:55:40 +0000464}
465
466/*
467 * union nlm_testrply switch (nlm_stats stat) {
468 * case LCK_DENIED:
469 * struct nlm_holder holder;
470 * default:
471 * void;
472 * };
473 *
474 * struct nlm_testres {
475 * netobj cookie;
476 * nlm_testrply test_stat;
477 * };
478 */
479static void encode_nlm_testrply(struct xdr_stream *xdr,
480 const struct nlm_res *result)
481{
482 if (result->status == nlm_lck_denied)
483 encode_nlm_holder(xdr, result);
484}
485
Chuck Lever9f06c712010-12-14 14:59:18 +0000486static void nlm_xdr_enc_testres(struct rpc_rqst *req,
487 struct xdr_stream *xdr,
488 const struct nlm_res *result)
Chuck Lever2b061f92010-12-14 14:55:40 +0000489{
Chuck Lever9f06c712010-12-14 14:59:18 +0000490 encode_cookie(xdr, &result->cookie);
491 encode_nlm_stat(xdr, result->status);
492 encode_nlm_testrply(xdr, result);
Chuck Lever2b061f92010-12-14 14:55:40 +0000493}
494
495
496/*
497 * NLMv3 XDR decode functions
498 *
499 * NLMv3 result types are defined in Chapter 10 of The Open Group's
500 * "Protocols for Interworking: XNFS, Version 3W".
501 */
502
503/*
504 * union nlm_testrply switch (nlm_stats stat) {
505 * case LCK_DENIED:
506 * struct nlm_holder holder;
507 * default:
508 * void;
509 * };
510 *
511 * struct nlm_testres {
512 * netobj cookie;
513 * nlm_testrply test_stat;
514 * };
515 */
516static int decode_nlm_testrply(struct xdr_stream *xdr,
517 struct nlm_res *result)
518{
519 int error;
520
521 error = decode_nlm_stat(xdr, &result->status);
522 if (unlikely(error))
523 goto out;
524 if (result->status == nlm_lck_denied)
525 error = decode_nlm_holder(xdr, result);
526out:
527 return error;
528}
529
Chuck Leverbf269552010-12-14 14:59:29 +0000530static int nlm_xdr_dec_testres(struct rpc_rqst *req,
531 struct xdr_stream *xdr,
Chuck Lever2b061f92010-12-14 14:55:40 +0000532 struct nlm_res *result)
533{
Chuck Lever2b061f92010-12-14 14:55:40 +0000534 int error;
535
Chuck Leverbf269552010-12-14 14:59:29 +0000536 error = decode_cookie(xdr, &result->cookie);
Chuck Lever2b061f92010-12-14 14:55:40 +0000537 if (unlikely(error))
538 goto out;
Chuck Leverbf269552010-12-14 14:59:29 +0000539 error = decode_nlm_testrply(xdr, result);
Chuck Lever2b061f92010-12-14 14:55:40 +0000540out:
541 return error;
542}
543
544/*
545 * struct nlm_res {
546 * netobj cookie;
547 * nlm_stat stat;
548 * };
549 */
Chuck Leverbf269552010-12-14 14:59:29 +0000550static int nlm_xdr_dec_res(struct rpc_rqst *req,
551 struct xdr_stream *xdr,
Chuck Lever2b061f92010-12-14 14:55:40 +0000552 struct nlm_res *result)
553{
Chuck Lever2b061f92010-12-14 14:55:40 +0000554 int error;
555
Chuck Leverbf269552010-12-14 14:59:29 +0000556 error = decode_cookie(xdr, &result->cookie);
Chuck Lever2b061f92010-12-14 14:55:40 +0000557 if (unlikely(error))
558 goto out;
Chuck Leverbf269552010-12-14 14:59:29 +0000559 error = decode_nlm_stat(xdr, &result->status);
Chuck Lever2b061f92010-12-14 14:55:40 +0000560out:
561 return error;
562}
563
564
565/*
566 * For NLM, a void procedure really returns nothing
567 */
568#define nlm_xdr_dec_norep NULL
569
570#define PROC(proc, argtype, restype) \
571[NLMPROC_##proc] = { \
572 .p_proc = NLMPROC_##proc, \
Chuck Lever9f06c712010-12-14 14:59:18 +0000573 .p_encode = (kxdreproc_t)nlm_xdr_enc_##argtype, \
Chuck Leverbf269552010-12-14 14:59:29 +0000574 .p_decode = (kxdrdproc_t)nlm_xdr_dec_##restype, \
Chuck Lever2b061f92010-12-14 14:55:40 +0000575 .p_arglen = NLM_##argtype##_sz, \
576 .p_replen = NLM_##restype##_sz, \
577 .p_statidx = NLMPROC_##proc, \
578 .p_name = #proc, \
579 }
580
581static struct rpc_procinfo nlm_procedures[] = {
582 PROC(TEST, testargs, testres),
583 PROC(LOCK, lockargs, res),
584 PROC(CANCEL, cancargs, res),
585 PROC(UNLOCK, unlockargs, res),
586 PROC(GRANTED, testargs, res),
587 PROC(TEST_MSG, testargs, norep),
588 PROC(LOCK_MSG, lockargs, norep),
589 PROC(CANCEL_MSG, cancargs, norep),
590 PROC(UNLOCK_MSG, unlockargs, norep),
591 PROC(GRANTED_MSG, testargs, norep),
592 PROC(TEST_RES, testres, norep),
593 PROC(LOCK_RES, res, norep),
594 PROC(CANCEL_RES, res, norep),
595 PROC(UNLOCK_RES, res, norep),
596 PROC(GRANTED_RES, res, norep),
597};
598
Trond Myklebusta613fa12012-01-20 13:53:56 -0500599static const struct rpc_version nlm_version1 = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000600 .number = 1,
601 .nrprocs = ARRAY_SIZE(nlm_procedures),
602 .procs = nlm_procedures,
603};
604
Trond Myklebusta613fa12012-01-20 13:53:56 -0500605static const struct rpc_version nlm_version3 = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000606 .number = 3,
607 .nrprocs = ARRAY_SIZE(nlm_procedures),
608 .procs = nlm_procedures,
609};
610
Trond Myklebusta613fa12012-01-20 13:53:56 -0500611static const struct rpc_version *nlm_versions[] = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000612 [1] = &nlm_version1,
613 [3] = &nlm_version3,
614#ifdef CONFIG_LOCKD_V4
615 [4] = &nlm_version4,
616#endif
617};
618
619static struct rpc_stat nlm_rpc_stats;
620
Trond Myklebusta613fa12012-01-20 13:53:56 -0500621const struct rpc_program nlm_program = {
Chuck Lever2b061f92010-12-14 14:55:40 +0000622 .name = "lockd",
623 .number = NLM_PROGRAM,
624 .nrvers = ARRAY_SIZE(nlm_versions),
625 .version = nlm_versions,
626 .stats = &nlm_rpc_stats,
627};