xref: /openbmc/linux/fs/lockd/xdr.c (revision e868d61272caa648214046a096e5a6bfc068dc8c)
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 		printk(KERN_NOTICE
66 			"lockd: bad cookie size %d (only cookies under %d bytes are supported.)\n", len, NLM_MAXCOOKIELEN);
67 		return NULL;
68 	}
69 	return p;
70 }
71 
72 static inline __be32 *
73 nlm_encode_cookie(__be32 *p, struct nlm_cookie *c)
74 {
75 	*p++ = htonl(c->len);
76 	memcpy(p, c->data, c->len);
77 	p+=XDR_QUADLEN(c->len);
78 	return p;
79 }
80 
81 static __be32 *
82 nlm_decode_fh(__be32 *p, struct nfs_fh *f)
83 {
84 	unsigned int	len;
85 
86 	if ((len = ntohl(*p++)) != NFS2_FHSIZE) {
87 		printk(KERN_NOTICE
88 			"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 	argp->vers = *p++;
355 	argp->proto = *p++;
356 	return xdr_argsize_check(rqstp, p);
357 }
358 
359 int
360 nlmsvc_decode_res(struct svc_rqst *rqstp, __be32 *p, struct nlm_res *resp)
361 {
362 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
363 		return 0;
364 	resp->status = *p++;
365 	return xdr_argsize_check(rqstp, p);
366 }
367 
368 int
369 nlmsvc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
370 {
371 	return xdr_argsize_check(rqstp, p);
372 }
373 
374 int
375 nlmsvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
376 {
377 	return xdr_ressize_check(rqstp, p);
378 }
379 
380 /*
381  * Now, the client side XDR functions
382  */
383 #ifdef NLMCLNT_SUPPORT_SHARES
384 static int
385 nlmclt_decode_void(struct rpc_rqst *req, u32 *p, void *ptr)
386 {
387 	return 0;
388 }
389 #endif
390 
391 static int
392 nlmclt_encode_testargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
393 {
394 	struct nlm_lock	*lock = &argp->lock;
395 
396 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
397 		return -EIO;
398 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
399 	if (!(p = nlm_encode_lock(p, lock)))
400 		return -EIO;
401 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
402 	return 0;
403 }
404 
405 static int
406 nlmclt_decode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
407 {
408 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
409 		return -EIO;
410 	resp->status = *p++;
411 	if (resp->status == nlm_lck_denied) {
412 		struct file_lock	*fl = &resp->lock.fl;
413 		u32			excl;
414 		s32			start, len, end;
415 
416 		memset(&resp->lock, 0, sizeof(resp->lock));
417 		locks_init_lock(fl);
418 		excl = ntohl(*p++);
419 		resp->lock.svid = ntohl(*p++);
420 		fl->fl_pid = (pid_t)resp->lock.svid;
421 		if (!(p = nlm_decode_oh(p, &resp->lock.oh)))
422 			return -EIO;
423 
424 		fl->fl_flags = FL_POSIX;
425 		fl->fl_type  = excl? F_WRLCK : F_RDLCK;
426 		start = ntohl(*p++);
427 		len = ntohl(*p++);
428 		end = start + len - 1;
429 
430 		fl->fl_start = s32_to_loff_t(start);
431 		if (len == 0 || end < 0)
432 			fl->fl_end = OFFSET_MAX;
433 		else
434 			fl->fl_end = s32_to_loff_t(end);
435 	}
436 	return 0;
437 }
438 
439 
440 static int
441 nlmclt_encode_lockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
442 {
443 	struct nlm_lock	*lock = &argp->lock;
444 
445 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
446 		return -EIO;
447 	*p++ = argp->block? xdr_one : xdr_zero;
448 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
449 	if (!(p = nlm_encode_lock(p, lock)))
450 		return -EIO;
451 	*p++ = argp->reclaim? xdr_one : xdr_zero;
452 	*p++ = htonl(argp->state);
453 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
454 	return 0;
455 }
456 
457 static int
458 nlmclt_encode_cancargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
459 {
460 	struct nlm_lock	*lock = &argp->lock;
461 
462 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
463 		return -EIO;
464 	*p++ = argp->block? xdr_one : xdr_zero;
465 	*p++ = (lock->fl.fl_type == F_WRLCK)? xdr_one : xdr_zero;
466 	if (!(p = nlm_encode_lock(p, lock)))
467 		return -EIO;
468 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
469 	return 0;
470 }
471 
472 static int
473 nlmclt_encode_unlockargs(struct rpc_rqst *req, __be32 *p, nlm_args *argp)
474 {
475 	struct nlm_lock	*lock = &argp->lock;
476 
477 	if (!(p = nlm_encode_cookie(p, &argp->cookie)))
478 		return -EIO;
479 	if (!(p = nlm_encode_lock(p, lock)))
480 		return -EIO;
481 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
482 	return 0;
483 }
484 
485 static int
486 nlmclt_encode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
487 {
488 	if (!(p = nlm_encode_cookie(p, &resp->cookie)))
489 		return -EIO;
490 	*p++ = resp->status;
491 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
492 	return 0;
493 }
494 
495 static int
496 nlmclt_encode_testres(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
497 {
498 	if (!(p = nlm_encode_testres(p, resp)))
499 		return -EIO;
500 	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
501 	return 0;
502 }
503 
504 static int
505 nlmclt_decode_res(struct rpc_rqst *req, __be32 *p, struct nlm_res *resp)
506 {
507 	if (!(p = nlm_decode_cookie(p, &resp->cookie)))
508 		return -EIO;
509 	resp->status = *p++;
510 	return 0;
511 }
512 
513 #if (NLMCLNT_OHSIZE > XDR_MAX_NETOBJ)
514 #  error "NLM host name cannot be larger than XDR_MAX_NETOBJ!"
515 #endif
516 
517 /*
518  * Buffer requirements for NLM
519  */
520 #define NLM_void_sz		0
521 #define NLM_cookie_sz		1+XDR_QUADLEN(NLM_MAXCOOKIELEN)
522 #define NLM_caller_sz		1+XDR_QUADLEN(NLMCLNT_OHSIZE)
523 #define NLM_owner_sz		1+XDR_QUADLEN(NLMCLNT_OHSIZE)
524 #define NLM_fhandle_sz		1+XDR_QUADLEN(NFS2_FHSIZE)
525 #define NLM_lock_sz		3+NLM_caller_sz+NLM_owner_sz+NLM_fhandle_sz
526 #define NLM_holder_sz		4+NLM_owner_sz
527 
528 #define NLM_testargs_sz		NLM_cookie_sz+1+NLM_lock_sz
529 #define NLM_lockargs_sz		NLM_cookie_sz+4+NLM_lock_sz
530 #define NLM_cancargs_sz		NLM_cookie_sz+2+NLM_lock_sz
531 #define NLM_unlockargs_sz	NLM_cookie_sz+NLM_lock_sz
532 
533 #define NLM_testres_sz		NLM_cookie_sz+1+NLM_holder_sz
534 #define NLM_res_sz		NLM_cookie_sz+1
535 #define NLM_norep_sz		0
536 
537 /*
538  * For NLM, a void procedure really returns nothing
539  */
540 #define nlmclt_decode_norep	NULL
541 
542 #define PROC(proc, argtype, restype)	\
543 [NLMPROC_##proc] = {							\
544 	.p_proc      = NLMPROC_##proc,					\
545 	.p_encode    = (kxdrproc_t) nlmclt_encode_##argtype,		\
546 	.p_decode    = (kxdrproc_t) nlmclt_decode_##restype,		\
547 	.p_arglen    = NLM_##argtype##_sz,				\
548 	.p_replen    = NLM_##restype##_sz,				\
549 	.p_statidx   = NLMPROC_##proc,					\
550 	.p_name      = #proc,						\
551 	}
552 
553 static struct rpc_procinfo	nlm_procedures[] = {
554     PROC(TEST,		testargs,	testres),
555     PROC(LOCK,		lockargs,	res),
556     PROC(CANCEL,	cancargs,	res),
557     PROC(UNLOCK,	unlockargs,	res),
558     PROC(GRANTED,	testargs,	res),
559     PROC(TEST_MSG,	testargs,	norep),
560     PROC(LOCK_MSG,	lockargs,	norep),
561     PROC(CANCEL_MSG,	cancargs,	norep),
562     PROC(UNLOCK_MSG,	unlockargs,	norep),
563     PROC(GRANTED_MSG,	testargs,	norep),
564     PROC(TEST_RES,	testres,	norep),
565     PROC(LOCK_RES,	res,		norep),
566     PROC(CANCEL_RES,	res,		norep),
567     PROC(UNLOCK_RES,	res,		norep),
568     PROC(GRANTED_RES,	res,		norep),
569 #ifdef NLMCLNT_SUPPORT_SHARES
570     PROC(SHARE,		shareargs,	shareres),
571     PROC(UNSHARE,	shareargs,	shareres),
572     PROC(NM_LOCK,	lockargs,	res),
573     PROC(FREE_ALL,	notify,		void),
574 #endif
575 };
576 
577 static struct rpc_version	nlm_version1 = {
578 		.number		= 1,
579 		.nrprocs	= 16,
580 		.procs		= nlm_procedures,
581 };
582 
583 static struct rpc_version	nlm_version3 = {
584 		.number		= 3,
585 		.nrprocs	= 24,
586 		.procs		= nlm_procedures,
587 };
588 
589 #ifdef 	CONFIG_LOCKD_V4
590 extern struct rpc_version nlm_version4;
591 #endif
592 
593 static struct rpc_version *	nlm_versions[] = {
594 	[1] = &nlm_version1,
595 	[3] = &nlm_version3,
596 #ifdef 	CONFIG_LOCKD_V4
597 	[4] = &nlm_version4,
598 #endif
599 };
600 
601 static struct rpc_stat		nlm_stats;
602 
603 struct rpc_program		nlm_program = {
604 		.name		= "lockd",
605 		.number		= NLM_PROGRAM,
606 		.nrvers		= ARRAY_SIZE(nlm_versions),
607 		.version	= nlm_versions,
608 		.stats		= &nlm_stats,
609 };
610 
611 #ifdef RPC_DEBUG
612 const char *nlmdbg_cookie2a(const struct nlm_cookie *cookie)
613 {
614 	/*
615 	 * We can get away with a static buffer because we're only
616 	 * called with BKL held.
617 	 */
618 	static char buf[2*NLM_MAXCOOKIELEN+1];
619 	int i;
620 	int len = sizeof(buf);
621 	char *p = buf;
622 
623 	len--;	/* allow for trailing \0 */
624 	if (len < 3)
625 		return "???";
626 	for (i = 0 ; i < cookie->len ; i++) {
627 		if (len < 2) {
628 			strcpy(p-3, "...");
629 			break;
630 		}
631 		sprintf(p, "%02x", cookie->data[i]);
632 		p += 2;
633 		len -= 2;
634 	}
635 	*p = '\0';
636 
637 	return buf;
638 }
639 #endif
640