xref: /openbmc/linux/fs/lockd/xdr.c (revision 9ac8d3fb)
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/types.h>
10 #include <linux/sched.h>
11 #include <linux/utsname.h>
12 #include <linux/nfs.h>
13 
14 #include <linux/sunrpc/xdr.h>
15 #include <linux/sunrpc/clnt.h>
16 #include <linux/sunrpc/svc.h>
17 #include <linux/sunrpc/stats.h>
18 #include <linux/lockd/lockd.h>
19 #include <linux/lockd/sm_inter.h>
20 
21 #define NLMDBG_FACILITY		NLMDBG_XDR
22 
23 
24 static inline loff_t
25 s32_to_loff_t(__s32 offset)
26 {
27 	return (loff_t)offset;
28 }
29 
30 static inline __s32
31 loff_t_to_s32(loff_t offset)
32 {
33 	__s32 res;
34 	if (offset >= NLM_OFFSET_MAX)
35 		res = NLM_OFFSET_MAX;
36 	else if (offset <= -NLM_OFFSET_MAX)
37 		res = -NLM_OFFSET_MAX;
38 	else
39 		res = offset;
40 	return res;
41 }
42 
43 /*
44  * XDR functions for basic NLM types
45  */
46 static __be32 *nlm_decode_cookie(__be32 *p, struct nlm_cookie *c)
47 {
48 	unsigned int	len;
49 
50 	len = ntohl(*p++);
51 
52 	if(len==0)
53 	{
54 		c->len=4;
55 		memset(c->data, 0, 4);	/* hockeypux brain damage */
56 	}
57 	else if(len<=NLM_MAXCOOKIELEN)
58 	{
59 		c->len=len;
60 		memcpy(c->data, p, len);
61 		p+=XDR_QUADLEN(len);
62 	}
63 	else
64 	{
65 		dprintk("lockd: bad cookie size %d (only cookies under "
66 			"%d bytes are supported.)\n",
67 				len, NLM_MAXCOOKIELEN);
68 		return NULL;
69 	}
70 	return p;
71 }
72 
73 static inline __be32 *
74 nlm_encode_cookie(__be32 *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 __be32 *
83 nlm_decode_fh(__be32 *p, struct nfs_fh *f)
84 {
85 	unsigned int	len;
86 
87 	if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
88 		dprintk("lockd: bad fhandle size %d (should be %d)\n",
89 			len, NFS2_FHSIZE);
90 		return NULL;
91 	}
92 	f->size = NFS2_FHSIZE;
93 	memset(f->data, 0, sizeof(f->data));
94 	memcpy(f->data, p, NFS2_FHSIZE);
95 	return p + XDR_QUADLEN(NFS2_FHSIZE);
96 }
97 
98 static inline __be32 *
99 nlm_encode_fh(__be32 *p, struct nfs_fh *f)
100 {
101 	*p++ = htonl(NFS2_FHSIZE);
102 	memcpy(p, f->data, NFS2_FHSIZE);
103 	return p + XDR_QUADLEN(NFS2_FHSIZE);
104 }
105 
106 /*
107  * Encode and decode owner handle
108  */
109 static inline __be32 *
110 nlm_decode_oh(__be32 *p, struct xdr_netobj *oh)
111 {
112 	return xdr_decode_netobj(p, oh);
113 }
114 
115 static inline __be32 *
116 nlm_encode_oh(__be32 *p, struct xdr_netobj *oh)
117 {
118 	return xdr_encode_netobj(p, oh);
119 }
120 
121 static __be32 *
122 nlm_decode_lock(__be32 *p, struct nlm_lock *lock)
123 {
124 	struct file_lock	*fl = &lock->fl;
125 	s32			start, len, end;
126 
127 	if (!(p = xdr_decode_string_inplace(p, &lock->caller,
128 					    &lock->len,
129 					    NLM_MAXSTRLEN))
130 	 || !(p = nlm_decode_fh(p, &lock->fh))
131 	 || !(p = nlm_decode_oh(p, &lock->oh)))
132 		return NULL;
133 	lock->svid  = ntohl(*p++);
134 
135 	locks_init_lock(fl);
136 	fl->fl_owner = current->files;
137 	fl->fl_pid   = (pid_t)lock->svid;
138 	fl->fl_flags = FL_POSIX;
139 	fl->fl_type  = F_RDLCK;		/* as good as anything else */
140 	start = ntohl(*p++);
141 	len = ntohl(*p++);
142 	end = start + len - 1;
143 
144 	fl->fl_start = s32_to_loff_t(start);
145 
146 	if (len == 0 || end < 0)
147 		fl->fl_end = OFFSET_MAX;
148 	else
149 		fl->fl_end = s32_to_loff_t(end);
150 	return p;
151 }
152 
153 /*
154  * Encode a lock as part of an NLM call
155  */
156 static __be32 *
157 nlm_encode_lock(__be32 *p, struct nlm_lock *lock)
158 {
159 	struct file_lock	*fl = &lock->fl;
160 	__s32			start, len;
161 
162 	if (!(p = xdr_encode_string(p, lock->caller))
163 	 || !(p = nlm_encode_fh(p, &lock->fh))
164 	 || !(p = nlm_encode_oh(p, &lock->oh)))
165 		return NULL;
166 
167 	if (fl->fl_start > NLM_OFFSET_MAX
168 	 || (fl->fl_end > NLM_OFFSET_MAX && fl->fl_end != OFFSET_MAX))
169 		return NULL;
170 
171 	start = loff_t_to_s32(fl->fl_start);
172 	if (fl->fl_end == OFFSET_MAX)
173 		len = 0;
174 	else
175 		len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
176 
177 	*p++ = htonl(lock->svid);
178 	*p++ = htonl(start);
179 	*p++ = htonl(len);
180 
181 	return p;
182 }
183 
184 /*
185  * Encode result of a TEST/TEST_MSG call
186  */
187 static __be32 *
188 nlm_encode_testres(__be32 *p, struct nlm_res *resp)
189 {
190 	s32		start, len;
191 
192 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
193 		return NULL;
194 	*p++ = resp->status;
195 
196 	if (resp->status == nlm_lck_denied) {
197 		struct file_lock	*fl = &resp->lock.fl;
198 
199 		*p++ = (fl->fl_type == F_RDLCK)? xdr_zero : xdr_one;
200 		*p++ = htonl(resp->lock.svid);
201 
202 		/* Encode owner handle. */
203 		if (!(p = xdr_encode_netobj(p, &resp->lock.oh)))
204 			return NULL;
205 
206 		start = loff_t_to_s32(fl->fl_start);
207 		if (fl->fl_end == OFFSET_MAX)
208 			len = 0;
209 		else
210 			len = loff_t_to_s32(fl->fl_end - fl->fl_start + 1);
211 
212 		*p++ = htonl(start);
213 		*p++ = htonl(len);
214 	}
215 
216 	return p;
217 }
218 
219 
220 /*
221  * First, the server side XDR functions
222  */
223 int
224 nlmsvc_decode_testargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
225 {
226 	u32	exclusive;
227 
228 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
229 		return 0;
230 
231 	exclusive = ntohl(*p++);
232 	if (!(p = nlm_decode_lock(p, &argp->lock)))
233 		return 0;
234 	if (exclusive)
235 		argp->lock.fl.fl_type = F_WRLCK;
236 
237 	return xdr_argsize_check(rqstp, p);
238 }
239 
240 int
241 nlmsvc_encode_testres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
242 {
243 	if (!(p = nlm_encode_testres(p, resp)))
244 		return 0;
245 	return xdr_ressize_check(rqstp, p);
246 }
247 
248 int
249 nlmsvc_decode_lockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
250 {
251 	u32	exclusive;
252 
253 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
254 		return 0;
255 	argp->block  = ntohl(*p++);
256 	exclusive    = ntohl(*p++);
257 	if (!(p = nlm_decode_lock(p, &argp->lock)))
258 		return 0;
259 	if (exclusive)
260 		argp->lock.fl.fl_type = F_WRLCK;
261 	argp->reclaim = ntohl(*p++);
262 	argp->state   = ntohl(*p++);
263 	argp->monitor = 1;		/* monitor client by default */
264 
265 	return xdr_argsize_check(rqstp, p);
266 }
267 
268 int
269 nlmsvc_decode_cancargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
270 {
271 	u32	exclusive;
272 
273 	if (!(p = nlm_decode_cookie(p, &argp->cookie)))
274 		return 0;
275 	argp->block = ntohl(*p++);
276 	exclusive = ntohl(*p++);
277 	if (!(p = nlm_decode_lock(p, &argp->lock)))
278 		return 0;
279 	if (exclusive)
280 		argp->lock.fl.fl_type = F_WRLCK;
281 	return xdr_argsize_check(rqstp, p);
282 }
283 
284 int
285 nlmsvc_decode_unlockargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
286 {
287 	if (!(p = nlm_decode_cookie(p, &argp->cookie))
288 	 || !(p = nlm_decode_lock(p, &argp->lock)))
289 		return 0;
290 	argp->lock.fl.fl_type = F_UNLCK;
291 	return xdr_argsize_check(rqstp, p);
292 }
293 
294 int
295 nlmsvc_decode_shareargs(struct svc_rqst *rqstp, __be32 *p, nlm_args *argp)
296 {
297 	struct nlm_lock	*lock = &argp->lock;
298 
299 	memset(lock, 0, sizeof(*lock));
300 	locks_init_lock(&lock->fl);
301 	lock->svid = ~(u32) 0;
302 	lock->fl.fl_pid = (pid_t)lock->svid;
303 
304 	if (!(p = nlm_decode_cookie(p, &argp->cookie))
305 	 || !(p = xdr_decode_string_inplace(p, &lock->caller,
306 					    &lock->len, NLM_MAXSTRLEN))
307 	 || !(p = nlm_decode_fh(p, &lock->fh))
308 	 || !(p = nlm_decode_oh(p, &lock->oh)))
309 		return 0;
310 	argp->fsm_mode = ntohl(*p++);
311 	argp->fsm_access = ntohl(*p++);
312 	return xdr_argsize_check(rqstp, p);
313 }
314 
315 int
316 nlmsvc_encode_shareres(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
317 {
318 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
319 		return 0;
320 	*p++ = resp->status;
321 	*p++ = xdr_zero;		/* sequence argument */
322 	return xdr_ressize_check(rqstp, p);
323 }
324 
325 int
326 nlmsvc_encode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
327 {
328 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
329 		return 0;
330 	*p++ = resp->status;
331 	return xdr_ressize_check(rqstp, p);
332 }
333 
334 int
335 nlmsvc_decode_notify(struct svc_rqst *rqstp, __be32 *p, struct nlm_args *argp)
336 {
337 	struct nlm_lock	*lock = &argp->lock;
338 
339 	if (!(p = xdr_decode_string_inplace(p, &lock->caller,
340 					    &lock->len, NLM_MAXSTRLEN)))
341 		return 0;
342 	argp->state = ntohl(*p++);
343 	return xdr_argsize_check(rqstp, p);
344 }
345 
346 int
347 nlmsvc_decode_reboot(struct svc_rqst *rqstp, __be32 *p, struct nlm_reboot *argp)
348 {
349 	if (!(p = xdr_decode_string_inplace(p, &argp->mon, &argp->len, SM_MAXSTRLEN)))
350 		return 0;
351 	argp->state = ntohl(*p++);
352 	/* Preserve the address in network byte order */
353 	argp->addr = *p++;
354 	return xdr_argsize_check(rqstp, p);
355 }
356 
357 int
358 nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
359 {
360 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
361 		return 0;
362 	resp->status = *p++;
363 	return xdr_argsize_check(rqstp, p);
364 }
365 
366 int
367 nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
368 {
369 	return xdr_argsize_check(rqstp, p);
370 }
371 
372 int
373 nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
374 {
375 	return xdr_ressize_check(rqstp, p);
376 }
377 
378 /*
379  * Now, the client side XDR functions
380  */
381 #ifdef NLMCLNT_SUPPORT_SHARES
382 static int
383 nlmclt_decode_void(struct rpc_rqst *req, u32 *p, void *ptr)
384 {
385 	return 0;
386 }
387 #endif
388 
389 static int
390 nlmclt_encode_testargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
391 {
392 	struct nlm_lock	*lock = &argp->lock;
393 
394 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
395 		return -EIO;
396 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
397 	if (!(p = nlm_encode_lock(p, lock)))
398 		return -EIO;
399 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
400 	return 0;
401 }
402 
403 static int
404 nlmclt_decode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
405 {
406 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
407 		return -EIO;
408 	resp->status = *p++;
409 	if (resp->status == nlm_lck_denied) {
410 		struct file_lock	*fl = &resp->lock.fl;
411 		u32			excl;
412 		s32			start, len, end;
413 
414 		memset(&resp->lock, 0, sizeof(resp->lock));
415 		locks_init_lock(fl);
416 		excl = ntohl(*p++);
417 		resp->lock.svid = ntohl(*p++);
418 		fl->fl_pid = (pid_t)resp->lock.svid;
419 		if (!(p = nlm_decode_oh(p, &resp->lock.oh)))
420 			return -EIO;
421 
422 		fl->fl_flags = FL_POSIX;
423 		fl->fl_type  = excl? F_WRLCK : F_RDLCK;
424 		start = ntohl(*p++);
425 		len = ntohl(*p++);
426 		end = start + len - 1;
427 
428 		fl->fl_start = s32_to_loff_t(start);
429 		if (len == 0 || end < 0)
430 			fl->fl_end = OFFSET_MAX;
431 		else
432 			fl->fl_end = s32_to_loff_t(end);
433 	}
434 	return 0;
435 }
436 
437 
438 static int
439 nlmclt_encode_lockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
440 {
441 	struct nlm_lock	*lock = &argp->lock;
442 
443 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
444 		return -EIO;
445 	*p++ = argp->block? xdr_one : xdr_zero;
446 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
447 	if (!(p = nlm_encode_lock(p, lock)))
448 		return -EIO;
449 	*p++ = argp->reclaim? xdr_one : xdr_zero;
450 	*p++ = htonl(argp->state);
451 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
452 	return 0;
453 }
454 
455 static int
456 nlmclt_encode_cancargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
457 {
458 	struct nlm_lock	*lock = &argp->lock;
459 
460 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
461 		return -EIO;
462 	*p++ = argp->block? xdr_one : xdr_zero;
463 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
464 	if (!(p = nlm_encode_lock(p, lock)))
465 		return -EIO;
466 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
467 	return 0;
468 }
469 
470 static int
471 nlmclt_encode_unlockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
472 {
473 	struct nlm_lock	*lock = &argp->lock;
474 
475 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
476 		return -EIO;
477 	if (!(p = nlm_encode_lock(p, lock)))
478 		return -EIO;
479 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
480 	return 0;
481 }
482 
483 static int
484 nlmclt_encode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
485 {
486 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
487 		return -EIO;
488 	*p++ = resp->status;
489 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
490 	return 0;
491 }
492 
493 static int
494 nlmclt_encode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
495 {
496 	if (!(p = nlm_encode_testres(p, resp)))
497 		return -EIO;
498 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
499 	return 0;
500 }
501 
502 static int
503 nlmclt_decode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
504 {
505 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
506 		return -EIO;
507 	resp->status = *p++;
508 	return 0;
509 }
510 
511 #if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
512 #  error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
513 #endif
514 
515 /*
516  * Buffer requirements for NLM
517  */
518 #define NLM_void_sz		0
519 #define NLM_cookie_sz		1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
520 #define NLM_caller_sz		1+XDR_QUADLEN(NLMCLNT_OHSIZE)
521 #define NLM_owner_sz		1+XDR_QUADLEN(NLMCLNT_OHSIZE)
522 #define NLM_fhandle_sz		1+XDR_QUADLEN(NFS2_FHSIZE)
523 #define NLM_lock_sz		3+NLM_caller_sz+NLM_owner_sz+NLM_fhandle_sz
524 #define NLM_holder_sz		4+NLM_owner_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 /*
536  * For NLM, a void procedure really returns nothing
537  */
538 #define nlmclt_decode_norep	NULL
539 
540 #define PROC(proc, argtype, restype)	\
541 [NLMPROC_##proc] = {							\
542 	.p_proc      = NLMPROC_##proc,					\
543 	.p_encode    = (kxdrproc_t) nlmclt_encode_##argtype,		\
544 	.p_decode    = (kxdrproc_t) nlmclt_decode_##restype,		\
545 	.p_arglen    = NLM_##argtype##_sz,				\
546 	.p_replen    = NLM_##restype##_sz,				\
547 	.p_statidx   = NLMPROC_##proc,					\
548 	.p_name      = #proc,						\
549 	}
550 
551 static struct rpc_procinfo	nlm_procedures[] = {
552     PROC(TEST,		testargs,	testres),
553     PROC(LOCK,		lockargs,	res),
554     PROC(CANCEL,	cancargs,	res),
555     PROC(UNLOCK,	unlockargs,	res),
556     PROC(GRANTED,	testargs,	res),
557     PROC(TEST_MSG,	testargs,	norep),
558     PROC(LOCK_MSG,	lockargs,	norep),
559     PROC(CANCEL_MSG,	cancargs,	norep),
560     PROC(UNLOCK_MSG,	unlockargs,	norep),
561     PROC(GRANTED_MSG,	testargs,	norep),
562     PROC(TEST_RES,	testres,	norep),
563     PROC(LOCK_RES,	res,		norep),
564     PROC(CANCEL_RES,	res,		norep),
565     PROC(UNLOCK_RES,	res,		norep),
566     PROC(GRANTED_RES,	res,		norep),
567 #ifdef NLMCLNT_SUPPORT_SHARES
568     PROC(SHARE,		shareargs,	shareres),
569     PROC(UNSHARE,	shareargs,	shareres),
570     PROC(NM_LOCK,	lockargs,	res),
571     PROC(FREE_ALL,	notify,		void),
572 #endif
573 };
574 
575 static struct rpc_version	nlm_version1 = {
576 		.number		= 1,
577 		.nrprocs	= 16,
578 		.procs		= nlm_procedures,
579 };
580 
581 static struct rpc_version	nlm_version3 = {
582 		.number		= 3,
583 		.nrprocs	= 24,
584 		.procs		= nlm_procedures,
585 };
586 
587 static struct rpc_version *	nlm_versions[] = {
588 	[1] = &nlm_version1,
589 	[3] = &nlm_version3,
590 #ifdef 	CONFIG_LOCKD_V4
591 	[4] = &nlm_version4,
592 #endif
593 };
594 
595 static struct rpc_stat		nlm_stats;
596 
597 struct rpc_program		nlm_program = {
598 		.name		= "lockd",
599 		.number		= NLM_PROGRAM,
600 		.nrvers		= ARRAY_SIZE(nlm_versions),
601 		.version	= nlm_versions,
602 		.stats		= &nlm_stats,
603 };
604 
605 #ifdef RPC_DEBUG
606 const char *nlmdbg_cookie2a(const struct nlm_cookie *cookie)
607 {
608 	/*
609 	 * We can get away with a static buffer because we're only
610 	 * called with BKL held.
611 	 */
612 	static char buf[2*NLM_MAXCOOKIELEN+1];
613 	unsigned int i, len = sizeof(buf);
614 	char *p = buf;
615 
616 	len--;	/* allow for trailing \0 */
617 	if (len < 3)
618 		return "???";
619 	for (i = 0 ; i < cookie->len ; i++) {
620 		if (len < 2) {
621 			strcpy(p-3, "...");
622 			break;
623 		}
624 		sprintf(p, "%02x", cookie->data[i]);
625 		p += 2;
626 		len -= 2;
627 	}
628 	*p = '\0';
629 
630 	return buf;
631 }
632 #endif
633