xref: /linux/fs/lockd/xdr.c (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /*
2  * linux/fs/lockd/xdr.c
3  *
4  * XDR support for lockd and the lock client.
5  *
6  * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
7  */
8 
9 #include <linux/config.h>
10 #include <linux/types.h>
11 #include <linux/sched.h>
12 #include <linux/utsname.h>
13 #include <linux/nfs.h>
14 
15 #include <linux/sunrpc/xdr.h>
16 #include <linux/sunrpc/clnt.h>
17 #include <linux/sunrpc/svc.h>
18 #include <linux/sunrpc/stats.h>
19 #include <linux/lockd/lockd.h>
20 #include <linux/lockd/sm_inter.h>
21 
22 #define NLMDBG_FACILITY		NLMDBG_XDR
23 
24 
25 static inline loff_t
26 s32_to_loff_t(__s32 offset)
27 {
28 	return (loff_t)offset;
29 }
30 
31 static inline __s32
32 loff_t_to_s32(loff_t offset)
33 {
34 	__s32 res;
35 	if (offset >= NLM_OFFSET_MAX)
36 		res = NLM_OFFSET_MAX;
37 	else if (offset <= -NLM_OFFSET_MAX)
38 		res = -NLM_OFFSET_MAX;
39 	else
40 		res = offset;
41 	return res;
42 }
43 
44 /*
45  * XDR functions for basic NLM types
46  */
47 static u32 *nlm_decode_cookie(u32 *p, struct nlm_cookie *c)
48 {
49 	unsigned int	len;
50 
51 	len = ntohl(*p++);
52 
53 	if(len==0)
54 	{
55 		c->len=4;
56 		memset(c->data, 0, 4);	/* hockeypux brain damage */
57 	}
58 	else if(len<=NLM_MAXCOOKIELEN)
59 	{
60 		c->len=len;
61 		memcpy(c->data, p, len);
62 		p+=XDR_QUADLEN(len);
63 	}
64 	else
65 	{
66 		printk(KERN_NOTICE
67 			"lockd: bad cookie size %d (only cookies under %d bytes are supported.)\n", len, NLM_MAXCOOKIELEN);
68 		return NULL;
69 	}
70 	return p;
71 }
72 
73 static inline u32 *
74 nlm_encode_cookie(u32 *p, struct nlm_cookie *c)
75 {
76 	*p++ = htonl(c->len);
77 	memcpy(p, c->data, c->len);
78 	p+=XDR_QUADLEN(c->len);
79 	return p;
80 }
81 
82 static u32 *
83 nlm_decode_fh(u32 *p, struct nfs_fh *f)
84 {
85 	unsigned int	len;
86 
87 	if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
88 		printk(KERN_NOTICE
89 			"lockd: bad fhandle size %d (should be %d)\n",
90 			len, NFS2_FHSIZE);
91 		return NULL;
92 	}
93 	f->size = NFS2_FHSIZE;
94 	memset(f->data, 0, sizeof(f->data));
95 	memcpy(f->data, p, NFS2_FHSIZE);
96 	return p + XDR_QUADLEN(NFS2_FHSIZE);
97 }
98 
99 static inline u32 *
100 nlm_encode_fh(u32 *p, struct nfs_fh *f)
101 {
102 	*p++ = htonl(NFS2_FHSIZE);
103 	memcpy(p, f->data, NFS2_FHSIZE);
104 	return p + XDR_QUADLEN(NFS2_FHSIZE);
105 }
106 
107 /*
108  * Encode and decode owner handle
109  */
110 static inline u32 *
111 nlm_decode_oh(u32 *p, struct xdr_netobj *oh)
112 {
113 	return xdr_decode_netobj(p, oh);
114 }
115 
116 static inline u32 *
117 nlm_encode_oh(u32 *p, struct xdr_netobj *oh)
118 {
119 	return xdr_encode_netobj(p, oh);
120 }
121 
122 static u32 *
123 nlm_decode_lock(u32 *p, struct nlm_lock *lock)
124 {
125 	struct file_lock	*fl = &lock->fl;
126 	s32			start, len, end;
127 
128 	if (!(p = xdr_decode_string_inplace(p, &lock->caller,
129 					    &lock->len,
130 					    NLM_MAXSTRLEN))
131 	 || !(p = nlm_decode_fh(p, &lock->fh))
132 	 || !(p = nlm_decode_oh(p, &lock->oh)))
133 		return NULL;
134 	lock->svid  = ntohl(*p++);
135 
136 	locks_init_lock(fl);
137 	fl->fl_owner = current->files;
138 	fl->fl_pid   = (pid_t)lock->svid;
139 	fl->fl_flags = FL_POSIX;
140 	fl->fl_type  = F_RDLCK;		/* as good as anything else */
141 	start = ntohl(*p++);
142 	len = ntohl(*p++);
143 	end = start + len - 1;
144 
145 	fl->fl_start = s32_to_loff_t(start);
146 
147 	if (len == 0 || end < 0)
148 		fl->fl_end = OFFSET_MAX;
149 	else
150 		fl->fl_end = s32_to_loff_t(end);
151 	return p;
152 }
153 
154 /*
155  * Encode a lock as part of an NLM call
156  */
157 static u32 *
158 nlm_encode_lock(u32 *p, struct nlm_lock *lock)
159 {
160 	struct file_lock	*fl = &lock->fl;
161 	__s32			start, len;
162 
163 	if (!(p = xdr_encode_string(p, lock->caller))
164 	 || !(p = nlm_encode_fh(p, &lock->fh))
165 	 || !(p = nlm_encode_oh(p, &lock->oh)))
166 		return NULL;
167 
168 	if (fl->fl_start > NLM_OFFSET_MAX
169 	 || (fl->fl_end > NLM_OFFSET_MAX && fl->fl_end != OFFSET_MAX))
170 		return NULL;
171 
172 	start = loff_t_to_s32(fl->fl_start);
173 	if (fl->fl_end == OFFSET_MAX)
174 		len = 0;
175 	else
176 		len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
177 
178 	*p++ = htonl(lock->svid);
179 	*p++ = htonl(start);
180 	*p++ = htonl(len);
181 
182 	return p;
183 }
184 
185 /*
186  * Encode result of a TEST/TEST_MSG call
187  */
188 static u32 *
189 nlm_encode_testres(u32 *p, struct nlm_res *resp)
190 {
191 	s32		start, len;
192 
193 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
194 		return NULL;
195 	*p++ = resp->status;
196 
197 	if (resp->status == nlm_lck_denied) {
198 		struct file_lock	*fl = &resp->lock.fl;
199 
200 		*p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
201 		*p++ = htonl(resp->lock.svid);
202 
203 		/* Encode owner handle. */
204 		if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
205 			return NULL;
206 
207 		start = loff_t_to_s32(fl->fl_start);
208 		if (fl->fl_end == OFFSET_MAX)
209 			len = 0;
210 		else
211 			len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
212 
213 		*p++ = htonl(start);
214 		*p++ = htonl(len);
215 	}
216 
217 	return p;
218 }
219 
220 
221 /*
222  * First, the server side XDR functions
223  */
224 int
225 nlmsvc_decode_testargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
226 {
227 	u32	exclusive;
228 
229 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
230 		return 0;
231 
232 	exclusive = ntohl(*p++);
233 	if (!(p = nlm_decode_lock(p, &argp->lock)))
234 		return 0;
235 	if (exclusive)
236 		argp->lock.fl.fl_type = F_WRLCK;
237 
238 	return xdr_argsize_check(rqstp, p);
239 }
240 
241 int
242 nlmsvc_encode_testres(struct svc_rqst *rqstp, u32 *p, struct nlm_res *resp)
243 {
244 	if (!(p = nlm_encode_testres(p, resp)))
245 		return 0;
246 	return xdr_ressize_check(rqstp, p);
247 }
248 
249 int
250 nlmsvc_decode_lockargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
251 {
252 	u32	exclusive;
253 
254 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
255 		return 0;
256 	argp->block  = ntohl(*p++);
257 	exclusive    = ntohl(*p++);
258 	if (!(p = nlm_decode_lock(p, &argp->lock)))
259 		return 0;
260 	if (exclusive)
261 		argp->lock.fl.fl_type = F_WRLCK;
262 	argp->reclaim = ntohl(*p++);
263 	argp->state   = ntohl(*p++);
264 	argp->monitor = 1;		/* monitor client by default */
265 
266 	return xdr_argsize_check(rqstp, p);
267 }
268 
269 int
270 nlmsvc_decode_cancargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
271 {
272 	u32	exclusive;
273 
274 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
275 		return 0;
276 	argp->block = ntohl(*p++);
277 	exclusive = ntohl(*p++);
278 	if (!(p = nlm_decode_lock(p, &argp->lock)))
279 		return 0;
280 	if (exclusive)
281 		argp->lock.fl.fl_type = F_WRLCK;
282 	return xdr_argsize_check(rqstp, p);
283 }
284 
285 int
286 nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
287 {
288 	if (!(p = nlm_decode_cookie(p, &argp->cookie))
289 	 || !(p = nlm_decode_lock(p, &argp->lock)))
290 		return 0;
291 	argp->lock.fl.fl_type = F_UNLCK;
292 	return xdr_argsize_check(rqstp, p);
293 }
294 
295 int
296 nlmsvc_decode_shareargs(struct svc_rqst *rqstp, u32 *p, nlm_args *argp)
297 {
298 	struct nlm_lock	*lock = &argp->lock;
299 
300 	memset(lock, 0, sizeof(*lock));
301 	locks_init_lock(&lock->fl);
302 	lock->svid = ~(u32) 0;
303 	lock->fl.fl_pid = (pid_t)lock->svid;
304 
305 	if (!(p = nlm_decode_cookie(p, &argp->cookie))
306 	 || !(p = xdr_decode_string_inplace(p, &lock->caller,
307 					    &lock->len, NLM_MAXSTRLEN))
308 	 || !(p = nlm_decode_fh(p, &lock->fh))
309 	 || !(p = nlm_decode_oh(p, &lock->oh)))
310 		return 0;
311 	argp->fsm_mode = ntohl(*p++);
312 	argp->fsm_access = ntohl(*p++);
313 	return xdr_argsize_check(rqstp, p);
314 }
315 
316 int
317 nlmsvc_encode_shareres(struct svc_rqst *rqstp, u32 *p, struct nlm_res *resp)
318 {
319 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
320 		return 0;
321 	*p++ = resp->status;
322 	*p++ = xdr_zero;		/* sequence argument */
323 	return xdr_ressize_check(rqstp, p);
324 }
325 
326 int
327 nlmsvc_encode_res(struct svc_rqst *rqstp, u32 *p, struct nlm_res *resp)
328 {
329 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
330 		return 0;
331 	*p++ = resp->status;
332 	return xdr_ressize_check(rqstp, p);
333 }
334 
335 int
336 nlmsvc_decode_notify(struct svc_rqst *rqstp, u32 *p, struct nlm_args *argp)
337 {
338 	struct nlm_lock	*lock = &argp->lock;
339 
340 	if (!(p = xdr_decode_string_inplace(p, &lock->caller,
341 					    &lock->len, NLM_MAXSTRLEN)))
342 		return 0;
343 	argp->state = ntohl(*p++);
344 	return xdr_argsize_check(rqstp, p);
345 }
346 
347 int
348 nlmsvc_decode_reboot(struct svc_rqst *rqstp, u32 *p, struct nlm_reboot *argp)
349 {
350 	if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
351 		return 0;
352 	argp->state = ntohl(*p++);
353 	/* Preserve the address in network byte order */
354 	argp->addr = *p++;
355 	argp->vers = *p++;
356 	argp->proto = *p++;
357 	return xdr_argsize_check(rqstp, p);
358 }
359 
360 int
361 nlmsvc_decode_res(struct svc_rqst *rqstp, u32 *p, struct nlm_res *resp)
362 {
363 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
364 		return 0;
365 	resp->status = ntohl(*p++);
366 	return xdr_argsize_check(rqstp, p);
367 }
368 
369 int
370 nlmsvc_decode_void(struct svc_rqst *rqstp, u32 *p, void *dummy)
371 {
372 	return xdr_argsize_check(rqstp, p);
373 }
374 
375 int
376 nlmsvc_encode_void(struct svc_rqst *rqstp, u32 *p, void *dummy)
377 {
378 	return xdr_ressize_check(rqstp, p);
379 }
380 
381 /*
382  * Now, the client side XDR functions
383  */
384 #ifdef NLMCLNT_SUPPORT_SHARES
385 static int
386 nlmclt_decode_void(struct rpc_rqst *req, u32 *p, void *ptr)
387 {
388 	return 0;
389 }
390 #endif
391 
392 static int
393 nlmclt_encode_testargs(struct rpc_rqst *req, u32 *p, nlm_args *argp)
394 {
395 	struct nlm_lock	*lock = &argp->lock;
396 
397 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
398 		return -EIO;
399 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
400 	if (!(p = nlm_encode_lock(p, lock)))
401 		return -EIO;
402 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
403 	return 0;
404 }
405 
406 static int
407 nlmclt_decode_testres(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
408 {
409 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
410 		return -EIO;
411 	resp->status = ntohl(*p++);
412 	if (resp->status == NLM_LCK_DENIED) {
413 		struct file_lock	*fl = &resp->lock.fl;
414 		u32			excl;
415 		s32			start, len, end;
416 
417 		memset(&resp->lock, 0, sizeof(resp->lock));
418 		locks_init_lock(fl);
419 		excl = ntohl(*p++);
420 		resp->lock.svid = ntohl(*p++);
421 		fl->fl_pid = (pid_t)resp->lock.svid;
422 		if (!(p = nlm_decode_oh(p, &resp->lock.oh)))
423 			return -EIO;
424 
425 		fl->fl_flags = FL_POSIX;
426 		fl->fl_type  = excl? F_WRLCK : F_RDLCK;
427 		start = ntohl(*p++);
428 		len = ntohl(*p++);
429 		end = start + len - 1;
430 
431 		fl->fl_start = s32_to_loff_t(start);
432 		if (len == 0 || end < 0)
433 			fl->fl_end = OFFSET_MAX;
434 		else
435 			fl->fl_end = s32_to_loff_t(end);
436 	}
437 	return 0;
438 }
439 
440 
441 static int
442 nlmclt_encode_lockargs(struct rpc_rqst *req, u32 *p, nlm_args *argp)
443 {
444 	struct nlm_lock	*lock = &argp->lock;
445 
446 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
447 		return -EIO;
448 	*p++ = argp->block? xdr_one : xdr_zero;
449 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
450 	if (!(p = nlm_encode_lock(p, lock)))
451 		return -EIO;
452 	*p++ = argp->reclaim? xdr_one : xdr_zero;
453 	*p++ = htonl(argp->state);
454 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
455 	return 0;
456 }
457 
458 static int
459 nlmclt_encode_cancargs(struct rpc_rqst *req, u32 *p, nlm_args *argp)
460 {
461 	struct nlm_lock	*lock = &argp->lock;
462 
463 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
464 		return -EIO;
465 	*p++ = argp->block? xdr_one : xdr_zero;
466 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
467 	if (!(p = nlm_encode_lock(p, lock)))
468 		return -EIO;
469 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
470 	return 0;
471 }
472 
473 static int
474 nlmclt_encode_unlockargs(struct rpc_rqst *req, u32 *p, nlm_args *argp)
475 {
476 	struct nlm_lock	*lock = &argp->lock;
477 
478 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
479 		return -EIO;
480 	if (!(p = nlm_encode_lock(p, lock)))
481 		return -EIO;
482 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
483 	return 0;
484 }
485 
486 static int
487 nlmclt_encode_res(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
488 {
489 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
490 		return -EIO;
491 	*p++ = resp->status;
492 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
493 	return 0;
494 }
495 
496 static int
497 nlmclt_encode_testres(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
498 {
499 	if (!(p = nlm_encode_testres(p, resp)))
500 		return -EIO;
501 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
502 	return 0;
503 }
504 
505 static int
506 nlmclt_decode_res(struct rpc_rqst *req, u32 *p, struct nlm_res *resp)
507 {
508 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
509 		return -EIO;
510 	resp->status = ntohl(*p++);
511 	return 0;
512 }
513 
514 /*
515  * Buffer requirements for NLM
516  */
517 #define NLM_void_sz		0
518 #define NLM_cookie_sz		1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
519 #define NLM_caller_sz		1+XDR_QUADLEN(sizeof(system_utsname.nodename))
520 #define NLM_netobj_sz		1+XDR_QUADLEN(XDR_MAX_NETOBJ)
521 /* #define NLM_owner_sz		1+XDR_QUADLEN(NLM_MAXOWNER) */
522 #define NLM_fhandle_sz		1+XDR_QUADLEN(NFS2_FHSIZE)
523 #define NLM_lock_sz		3+NLM_caller_sz+NLM_netobj_sz+NLM_fhandle_sz
524 #define NLM_holder_sz		4+NLM_netobj_sz
525 
526 #define NLM_testargs_sz		NLM_cookie_sz+1+NLM_lock_sz
527 #define NLM_lockargs_sz		NLM_cookie_sz+4+NLM_lock_sz
528 #define NLM_cancargs_sz		NLM_cookie_sz+2+NLM_lock_sz
529 #define NLM_unlockargs_sz	NLM_cookie_sz+NLM_lock_sz
530 
531 #define NLM_testres_sz		NLM_cookie_sz+1+NLM_holder_sz
532 #define NLM_res_sz		NLM_cookie_sz+1
533 #define NLM_norep_sz		0
534 
535 #ifndef MAX
536 # define MAX(a, b)		(((a) > (b))? (a) : (b))
537 #endif
538 
539 /*
540  * For NLM, a void procedure really returns nothing
541  */
542 #define nlmclt_decode_norep	NULL
543 
544 #define PROC(proc, argtype, restype)	\
545 [NLMPROC_##proc] = {							\
546 	.p_proc      = NLMPROC_##proc,					\
547 	.p_encode    = (kxdrproc_t) nlmclt_encode_##argtype,		\
548 	.p_decode    = (kxdrproc_t) nlmclt_decode_##restype,		\
549 	.p_bufsiz    = MAX(NLM_##argtype##_sz, NLM_##restype##_sz) << 2,	\
550 	.p_statidx   = NLMPROC_##proc,					\
551 	.p_name      = #proc,						\
552 	}
553 
554 static struct rpc_procinfo	nlm_procedures[] = {
555     PROC(TEST,		testargs,	testres),
556     PROC(LOCK,		lockargs,	res),
557     PROC(CANCEL,	cancargs,	res),
558     PROC(UNLOCK,	unlockargs,	res),
559     PROC(GRANTED,	testargs,	res),
560     PROC(TEST_MSG,	testargs,	norep),
561     PROC(LOCK_MSG,	lockargs,	norep),
562     PROC(CANCEL_MSG,	cancargs,	norep),
563     PROC(UNLOCK_MSG,	unlockargs,	norep),
564     PROC(GRANTED_MSG,	testargs,	norep),
565     PROC(TEST_RES,	testres,	norep),
566     PROC(LOCK_RES,	res,		norep),
567     PROC(CANCEL_RES,	res,		norep),
568     PROC(UNLOCK_RES,	res,		norep),
569     PROC(GRANTED_RES,	res,		norep),
570 #ifdef NLMCLNT_SUPPORT_SHARES
571     PROC(SHARE,		shareargs,	shareres),
572     PROC(UNSHARE,	shareargs,	shareres),
573     PROC(NM_LOCK,	lockargs,	res),
574     PROC(FREE_ALL,	notify,		void),
575 #endif
576 };
577 
578 static struct rpc_version	nlm_version1 = {
579 		.number		= 1,
580 		.nrprocs	= 16,
581 		.procs		= nlm_procedures,
582 };
583 
584 static struct rpc_version	nlm_version3 = {
585 		.number		= 3,
586 		.nrprocs	= 24,
587 		.procs		= nlm_procedures,
588 };
589 
590 #ifdef 	CONFIG_LOCKD_V4
591 extern struct rpc_version nlm_version4;
592 #endif
593 
594 static struct rpc_version *	nlm_versions[] = {
595 	[1] = &nlm_version1,
596 	[3] = &nlm_version3,
597 #ifdef 	CONFIG_LOCKD_V4
598 	[4] = &nlm_version4,
599 #endif
600 };
601 
602 static struct rpc_stat		nlm_stats;
603 
604 struct rpc_program		nlm_program = {
605 		.name		= "lockd",
606 		.number		= NLM_PROGRAM,
607 		.nrvers		= ARRAY_SIZE(nlm_versions),
608 		.version	= nlm_versions,
609 		.stats		= &nlm_stats,
610 };
611 
612 #ifdef RPC_DEBUG
613 const char *nlmdbg_cookie2a(const struct nlm_cookie *cookie)
614 {
615 	/*
616 	 * We can get away with a static buffer because we're only
617 	 * called with BKL held.
618 	 */
619 	static char buf[2*NLM_MAXCOOKIELEN+1];
620 	int i;
621 	int len = sizeof(buf);
622 	char *p = buf;
623 
624 	len--;	/* allow for trailing \0 */
625 	if (len < 3)
626 		return "???";
627 	for (i = 0 ; i < cookie->len ; i++) {
628 		if (len < 2) {
629 			strcpy(p-3, "...");
630 			break;
631 		}
632 		sprintf(p, "%02x", cookie->data[i]);
633 		p += 2;
634 		len -= 2;
635 	}
636 	*p = '\0';
637 
638 	return buf;
639 }
640 #endif
641