1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/lockd/clnt4xdr.c
4 *
5 * XDR functions to encode/decode NLM version 4 RPC arguments and results.
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 #include <uapi/linux/nfs3.h>
19
20 #define NLMDBG_FACILITY NLMDBG_XDR
21
22 #if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
23 # error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
24 #endif
25
26 #if (NLMCLNT_OHSIZE > NLM_MAXSTRLEN)
27 # error "NLM host name cannot be larger than NLM's maximum string length!"
28 #endif
29
30 /*
31 * Declare the space requirements for NLM arguments and replies as
32 * number of 32bit-words
33 */
34 #define NLM4_void_sz (0)
35 #define NLM4_cookie_sz (1+(NLM_MAXCOOKIELEN>>2))
36 #define NLM4_caller_sz (1+(NLMCLNT_OHSIZE>>2))
37 #define NLM4_owner_sz (1+(NLMCLNT_OHSIZE>>2))
38 #define NLM4_fhandle_sz (1+(NFS3_FHSIZE>>2))
39 #define NLM4_lock_sz (5+NLM4_caller_sz+NLM4_owner_sz+NLM4_fhandle_sz)
40 #define NLM4_holder_sz (6+NLM4_owner_sz)
41
42 #define NLM4_testargs_sz (NLM4_cookie_sz+1+NLM4_lock_sz)
43 #define NLM4_lockargs_sz (NLM4_cookie_sz+4+NLM4_lock_sz)
44 #define NLM4_cancargs_sz (NLM4_cookie_sz+2+NLM4_lock_sz)
45 #define NLM4_unlockargs_sz (NLM4_cookie_sz+NLM4_lock_sz)
46
47 #define NLM4_testres_sz (NLM4_cookie_sz+1+NLM4_holder_sz)
48 #define NLM4_res_sz (NLM4_cookie_sz+1)
49 #define NLM4_norep_sz (0)
50
51
52 static s64 loff_t_to_s64(loff_t offset)
53 {
54 s64 res;
55
56 if (offset >= NLM4_OFFSET_MAX)
57 res = NLM4_OFFSET_MAX;
58 else if (offset <= -NLM4_OFFSET_MAX)
59 res = -NLM4_OFFSET_MAX;
60 else
61 res = offset;
62 return res;
63 }
64
65 static void nlm4_compute_offsets(const struct nlm_lock *lock,
66 u64 *l_offset, u64 *l_len)
67 {
68 const struct file_lock *fl = &lock->fl;
69
70 *l_offset = loff_t_to_s64(fl->fl_start);
71 if (fl->fl_end == OFFSET_MAX)
72 *l_len = 0;
73 else
74 *l_len = loff_t_to_s64(fl->fl_end - fl->fl_start + 1);
75 }
76
77 /*
78 * Encode/decode NLMv4 basic data types
79 *
80 * Basic NLMv4 data types are defined in Appendix II, section 6.1.4
81 * of RFC 1813: "NFS Version 3 Protocol Specification" and in Chapter
82 * 10 of X/Open's "Protocols for Interworking: XNFS, Version 3W".
83 *
84 * Not all basic data types have their own encoding and decoding
85 * functions. For run-time efficiency, some data types are encoded
86 * or decoded inline.
87 */
88
89 static void encode_bool(struct xdr_stream *xdr, const int value)
90 {
91 __be32 *p;
92
93 p = xdr_reserve_space(xdr, 4);
94 *p = value ? xdr_one : xdr_zero;
95 }
96
97 static void encode_int32(struct xdr_stream *xdr, const s32 value)
98 {
99 __be32 *p;
100
101 p = xdr_reserve_space(xdr, 4);
102 *p = cpu_to_be32(value);
103 }
104
105 /*
106 * typedef opaque netobj<MAXNETOBJ_SZ>
107 */
108 static void encode_netobj(struct xdr_stream *xdr,
109 const u8 *data, const unsigned int length)
110 {
111 __be32 *p;
112
113 p = xdr_reserve_space(xdr, 4 + length);
114 xdr_encode_opaque(p, data, length);
115 }
116
117 static int decode_netobj(struct xdr_stream *xdr,
118 struct xdr_netobj *obj)
119 {
120 ssize_t ret;
121
122 ret = xdr_stream_decode_opaque_inline(xdr, (void *)&obj->data,
123 XDR_MAX_NETOBJ);
124 if (unlikely(ret < 0))
125 return -EIO;
126 obj->len = ret;
127 return 0;
128 }
129
130 /*
131 * netobj cookie;
132 */
133 static void encode_cookie(struct xdr_stream *xdr,
134 const struct nlm_cookie *cookie)
135 {
136 encode_netobj(xdr, (u8 *)&cookie->data, cookie->len);
137 }
138
139 static int decode_cookie(struct xdr_stream *xdr,
140 struct nlm_cookie *cookie)
141 {
142 u32 length;
143 __be32 *p;
144
145 p = xdr_inline_decode(xdr, 4);
146 if (unlikely(p == NULL))
147 goto out_overflow;
148 length = be32_to_cpup(p++);
149 /* apparently HPUX can return empty cookies */
150 if (length == 0)
151 goto out_hpux;
152 if (length > NLM_MAXCOOKIELEN)
153 goto out_size;
154 p = xdr_inline_decode(xdr, length);
155 if (unlikely(p == NULL))
156 goto out_overflow;
157 cookie->len = length;
158 memcpy(cookie->data, p, length);
159 return 0;
160 out_hpux:
161 cookie->len = 4;
162 memset(cookie->data, 0, 4);
163 return 0;
164 out_size:
165 dprintk("NFS: returned cookie was too long: %u\n", length);
166 return -EIO;
167 out_overflow:
168 return -EIO;
169 }
170
171 /*
172 * netobj fh;
173 */
174 static void encode_fh(struct xdr_stream *xdr, const struct nfs_fh *fh)
175 {
176 encode_netobj(xdr, (u8 *)&fh->data, fh->size);
177 }
178
179 /*
180 * enum nlm4_stats {
181 * NLM4_GRANTED = 0,
182 * NLM4_DENIED = 1,
183 * NLM4_DENIED_NOLOCKS = 2,
184 * NLM4_BLOCKED = 3,
185 * NLM4_DENIED_GRACE_PERIOD = 4,
186 * NLM4_DEADLCK = 5,
187 * NLM4_ROFS = 6,
188 * NLM4_STALE_FH = 7,
189 * NLM4_FBIG = 8,
190 * NLM4_FAILED = 9
191 * };
192 *
193 * struct nlm4_stat {
194 * nlm4_stats stat;
195 * };
196 *
197 * NB: we don't swap bytes for the NLM status values. The upper
198 * layers deal directly with the status value in network byte
199 * order.
200 */
201 static void encode_nlm4_stat(struct xdr_stream *xdr,
202 const __be32 stat)
203 {
204 __be32 *p;
205
206 BUG_ON(be32_to_cpu(stat) > NLM_FAILED);
207 p = xdr_reserve_space(xdr, 4);
208 *p = stat;
209 }
210
211 static int decode_nlm4_stat(struct xdr_stream *xdr, __be32 *stat)
212 {
213 __be32 *p;
214
215 p = xdr_inline_decode(xdr, 4);
216 if (unlikely(p == NULL))
217 goto out_overflow;
218 if (unlikely(ntohl(*p) > ntohl(nlm4_failed)))
219 goto out_bad_xdr;
220 *stat = *p;
221 return 0;
222 out_bad_xdr:
223 dprintk("%s: server returned invalid nlm4_stats value: %u\n",
224 __func__, be32_to_cpup(p));
225 return -EIO;
226 out_overflow:
227 return -EIO;
228 }
229
230 /*
231 * struct nlm4_holder {
232 * bool exclusive;
233 * int32 svid;
234 * netobj oh;
235 * uint64 l_offset;
236 * uint64 l_len;
237 * };
238 */
239 static void encode_nlm4_holder(struct xdr_stream *xdr,
240 const struct nlm_res *result)
241 {
242 const struct nlm_lock *lock = &result->lock;
243 u64 l_offset, l_len;
244 __be32 *p;
245
246 encode_bool(xdr, lock->fl.c.flc_type == F_RDLCK);
247 encode_int32(xdr, lock->svid);
248 encode_netobj(xdr, lock->oh.data, lock->oh.len);
249
250 p = xdr_reserve_space(xdr, 4 + 4);
251 nlm4_compute_offsets(lock, &l_offset, &l_len);
252 p = xdr_encode_hyper(p, l_offset);
253 xdr_encode_hyper(p, l_len);
254 }
255
256 static int decode_nlm4_holder(struct xdr_stream *xdr, struct nlm_res *result)
257 {
258 struct nlm_lock *lock = &result->lock;
259 struct file_lock *fl = &lock->fl;
260 u64 l_offset, l_len;
261 u32 exclusive;
262 int error;
263 __be32 *p;
264
265 memset(lock, 0, sizeof(*lock));
266 locks_init_lock(fl);
267
268 p = xdr_inline_decode(xdr, 4 + 4);
269 if (unlikely(p == NULL))
270 goto out_overflow;
271 exclusive = be32_to_cpup(p++);
272 lock->svid = be32_to_cpup(p);
273 fl->c.flc_pid = (pid_t)lock->svid;
274
275 error = decode_netobj(xdr, &lock->oh);
276 if (unlikely(error))
277 goto out;
278
279 p = xdr_inline_decode(xdr, 8 + 8);
280 if (unlikely(p == NULL))
281 goto out_overflow;
282
283 fl->c.flc_flags = FL_POSIX;
284 fl->c.flc_type = exclusive != 0 ? F_WRLCK : F_RDLCK;
285 p = xdr_decode_hyper(p, &l_offset);
286 xdr_decode_hyper(p, &l_len);
287 nlm4svc_set_file_lock_range(fl, l_offset, l_len);
288 error = 0;
289 out:
290 return error;
291 out_overflow:
292 return -EIO;
293 }
294
295 /*
296 * string caller_name<LM_MAXSTRLEN>;
297 */
298 static void encode_caller_name(struct xdr_stream *xdr, const char *name)
299 {
300 /* NB: client-side does not set lock->len */
301 u32 length = strlen(name);
302 __be32 *p;
303
304 p = xdr_reserve_space(xdr, 4 + length);
305 xdr_encode_opaque(p, name, length);
306 }
307
308 /*
309 * struct nlm4_lock {
310 * string caller_name<LM_MAXSTRLEN>;
311 * netobj fh;
312 * netobj oh;
313 * int32 svid;
314 * uint64 l_offset;
315 * uint64 l_len;
316 * };
317 */
318 static void encode_nlm4_lock(struct xdr_stream *xdr,
319 const struct nlm_lock *lock)
320 {
321 u64 l_offset, l_len;
322 __be32 *p;
323
324 encode_caller_name(xdr, lock->caller);
325 encode_fh(xdr, &lock->fh);
326 encode_netobj(xdr, lock->oh.data, lock->oh.len);
327
328 p = xdr_reserve_space(xdr, 4 + 8 + 8);
329 *p++ = cpu_to_be32(lock->svid);
330
331 nlm4_compute_offsets(lock, &l_offset, &l_len);
332 p = xdr_encode_hyper(p, l_offset);
333 xdr_encode_hyper(p, l_len);
334 }
335
336
337 /*
338 * NLMv4 XDR encode functions
339 *
340 * NLMv4 argument types are defined in Appendix II of RFC 1813:
341 * "NFS Version 3 Protocol Specification" and Chapter 10 of X/Open's
342 * "Protocols for Interworking: XNFS, Version 3W".
343 */
344
345 /*
346 * struct nlm4_testargs {
347 * netobj cookie;
348 * bool exclusive;
349 * struct nlm4_lock alock;
350 * };
351 */
352 static void nlm4_xdr_enc_testargs(struct rpc_rqst *req,
353 struct xdr_stream *xdr,
354 const void *data)
355 {
356 const struct nlm_args *args = data;
357 const struct nlm_lock *lock = &args->lock;
358
359 encode_cookie(xdr, &args->cookie);
360 encode_bool(xdr, lock->fl.c.flc_type == F_WRLCK);
361 encode_nlm4_lock(xdr, lock);
362 }
363
364 /*
365 * struct nlm4_lockargs {
366 * netobj cookie;
367 * bool block;
368 * bool exclusive;
369 * struct nlm4_lock alock;
370 * bool reclaim;
371 * int state;
372 * };
373 */
374 static void nlm4_xdr_enc_lockargs(struct rpc_rqst *req,
375 struct xdr_stream *xdr,
376 const void *data)
377 {
378 const struct nlm_args *args = data;
379 const struct nlm_lock *lock = &args->lock;
380
381 encode_cookie(xdr, &args->cookie);
382 encode_bool(xdr, args->block);
383 encode_bool(xdr, lock->fl.c.flc_type == F_WRLCK);
384 encode_nlm4_lock(xdr, lock);
385 encode_bool(xdr, args->reclaim);
386 encode_int32(xdr, args->state);
387 }
388
389 /*
390 * struct nlm4_cancargs {
391 * netobj cookie;
392 * bool block;
393 * bool exclusive;
394 * struct nlm4_lock alock;
395 * };
396 */
397 static void nlm4_xdr_enc_cancargs(struct rpc_rqst *req,
398 struct xdr_stream *xdr,
399 const void *data)
400 {
401 const struct nlm_args *args = data;
402 const struct nlm_lock *lock = &args->lock;
403
404 encode_cookie(xdr, &args->cookie);
405 encode_bool(xdr, args->block);
406 encode_bool(xdr, lock->fl.c.flc_type == F_WRLCK);
407 encode_nlm4_lock(xdr, lock);
408 }
409
410 /*
411 * struct nlm4_unlockargs {
412 * netobj cookie;
413 * struct nlm4_lock alock;
414 * };
415 */
416 static void nlm4_xdr_enc_unlockargs(struct rpc_rqst *req,
417 struct xdr_stream *xdr,
418 const void *data)
419 {
420 const struct nlm_args *args = data;
421 const struct nlm_lock *lock = &args->lock;
422
423 encode_cookie(xdr, &args->cookie);
424 encode_nlm4_lock(xdr, lock);
425 }
426
427 /*
428 * struct nlm4_res {
429 * netobj cookie;
430 * nlm4_stat stat;
431 * };
432 */
433 static void nlm4_xdr_enc_res(struct rpc_rqst *req,
434 struct xdr_stream *xdr,
435 const void *data)
436 {
437 const struct nlm_res *result = data;
438
439 encode_cookie(xdr, &result->cookie);
440 encode_nlm4_stat(xdr, result->status);
441 }
442
443 /*
444 * union nlm4_testrply switch (nlm4_stats stat) {
445 * case NLM4_DENIED:
446 * struct nlm4_holder holder;
447 * default:
448 * void;
449 * };
450 *
451 * struct nlm4_testres {
452 * netobj cookie;
453 * nlm4_testrply test_stat;
454 * };
455 */
456 static void nlm4_xdr_enc_testres(struct rpc_rqst *req,
457 struct xdr_stream *xdr,
458 const void *data)
459 {
460 const struct nlm_res *result = data;
461
462 encode_cookie(xdr, &result->cookie);
463 encode_nlm4_stat(xdr, result->status);
464 if (result->status == nlm_lck_denied)
465 encode_nlm4_holder(xdr, result);
466 }
467
468
469 /*
470 * NLMv4 XDR decode functions
471 *
472 * NLMv4 argument types are defined in Appendix II of RFC 1813:
473 * "NFS Version 3 Protocol Specification" and Chapter 10 of X/Open's
474 * "Protocols for Interworking: XNFS, Version 3W".
475 */
476
477 /*
478 * union nlm4_testrply switch (nlm4_stats stat) {
479 * case NLM4_DENIED:
480 * struct nlm4_holder holder;
481 * default:
482 * void;
483 * };
484 *
485 * struct nlm4_testres {
486 * netobj cookie;
487 * nlm4_testrply test_stat;
488 * };
489 */
490 static int decode_nlm4_testrply(struct xdr_stream *xdr,
491 struct nlm_res *result)
492 {
493 int error;
494
495 error = decode_nlm4_stat(xdr, &result->status);
496 if (unlikely(error))
497 goto out;
498 if (result->status == nlm_lck_denied)
499 error = decode_nlm4_holder(xdr, result);
500 out:
501 return error;
502 }
503
504 static int nlm4_xdr_dec_testres(struct rpc_rqst *req,
505 struct xdr_stream *xdr,
506 void *data)
507 {
508 struct nlm_res *result = data;
509 int error;
510
511 error = decode_cookie(xdr, &result->cookie);
512 if (unlikely(error))
513 goto out;
514 error = decode_nlm4_testrply(xdr, result);
515 out:
516 return error;
517 }
518
519 /*
520 * struct nlm4_res {
521 * netobj cookie;
522 * nlm4_stat stat;
523 * };
524 */
525 static int nlm4_xdr_dec_res(struct rpc_rqst *req,
526 struct xdr_stream *xdr,
527 void *data)
528 {
529 struct nlm_res *result = data;
530 int error;
531
532 error = decode_cookie(xdr, &result->cookie);
533 if (unlikely(error))
534 goto out;
535 error = decode_nlm4_stat(xdr, &result->status);
536 out:
537 return error;
538 }
539
540
541 /*
542 * For NLM, a void procedure really returns nothing
543 */
544 #define nlm4_xdr_dec_norep NULL
545
546 #define PROC(proc, argtype, restype) \
547 [NLMPROC_##proc] = { \
548 .p_proc = NLMPROC_##proc, \
549 .p_encode = nlm4_xdr_enc_##argtype, \
550 .p_decode = nlm4_xdr_dec_##restype, \
551 .p_arglen = NLM4_##argtype##_sz, \
552 .p_replen = NLM4_##restype##_sz, \
553 .p_statidx = NLMPROC_##proc, \
554 .p_name = #proc, \
555 }
556
557 static const struct rpc_procinfo nlm4_procedures[] = {
558 PROC(TEST, testargs, testres),
559 PROC(LOCK, lockargs, res),
560 PROC(CANCEL, cancargs, res),
561 PROC(UNLOCK, unlockargs, res),
562 PROC(GRANTED, testargs, res),
563 PROC(TEST_MSG, testargs, norep),
564 PROC(LOCK_MSG, lockargs, norep),
565 PROC(CANCEL_MSG, cancargs, norep),
566 PROC(UNLOCK_MSG, unlockargs, norep),
567 PROC(GRANTED_MSG, testargs, norep),
568 PROC(TEST_RES, testres, norep),
569 PROC(LOCK_RES, res, norep),
570 PROC(CANCEL_RES, res, norep),
571 PROC(UNLOCK_RES, res, norep),
572 PROC(GRANTED_RES, res, norep),
573 };
574
575 static unsigned int nlm_version4_counts[ARRAY_SIZE(nlm4_procedures)];
576 const struct rpc_version nlm_version4 = {
577 .number = 4,
578 .nrprocs = ARRAY_SIZE(nlm4_procedures),
579 .procs = nlm4_procedures,
580 .counts = nlm_version4_counts,
581 };
582
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