bsd_acct: plain current->real_parent access is not always safe
[linux-2.6] / fs / nfsd / nfs4proc.c
1 /*
2  *  fs/nfsd/nfs4proc.c
3  *
4  *  Server-side procedures for NFSv4.
5  *
6  *  Copyright (c) 2002 The Regents of the University of Michigan.
7  *  All rights reserved.
8  *
9  *  Kendrick Smith <kmsmith@umich.edu>
10  *  Andy Adamson   <andros@umich.edu>
11  *
12  *  Redistribution and use in source and binary forms, with or without
13  *  modification, are permitted provided that the following conditions
14  *  are met:
15  *
16  *  1. Redistributions of source code must retain the above copyright
17  *     notice, this list of conditions and the following disclaimer.
18  *  2. Redistributions in binary form must reproduce the above copyright
19  *     notice, this list of conditions and the following disclaimer in the
20  *     documentation and/or other materials provided with the distribution.
21  *  3. Neither the name of the University nor the names of its
22  *     contributors may be used to endorse or promote products derived
23  *     from this software without specific prior written permission.
24  *
25  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
26  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
27  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
28  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
32  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
33  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
34  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
35  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  */
37
38 #include <linux/param.h>
39 #include <linux/major.h>
40 #include <linux/slab.h>
41 #include <linux/file.h>
42
43 #include <linux/sunrpc/svc.h>
44 #include <linux/nfsd/nfsd.h>
45 #include <linux/nfsd/cache.h>
46 #include <linux/nfs4.h>
47 #include <linux/nfsd/state.h>
48 #include <linux/nfsd/xdr4.h>
49 #include <linux/nfs4_acl.h>
50 #include <linux/sunrpc/gss_api.h>
51
52 #define NFSDDBG_FACILITY                NFSDDBG_PROC
53
54 static inline void
55 fh_dup2(struct svc_fh *dst, struct svc_fh *src)
56 {
57         fh_put(dst);
58         dget(src->fh_dentry);
59         if (src->fh_export)
60                 cache_get(&src->fh_export->h);
61         *dst = *src;
62 }
63
64 static __be32
65 do_open_permission(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open, int accmode)
66 {
67         __be32 status;
68
69         if (open->op_truncate &&
70                 !(open->op_share_access & NFS4_SHARE_ACCESS_WRITE))
71                 return nfserr_inval;
72
73         if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
74                 accmode |= MAY_READ;
75         if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
76                 accmode |= (MAY_WRITE | MAY_TRUNC);
77         if (open->op_share_deny & NFS4_SHARE_DENY_WRITE)
78                 accmode |= MAY_WRITE;
79
80         status = fh_verify(rqstp, current_fh, S_IFREG, accmode);
81
82         return status;
83 }
84
85 static __be32
86 do_open_lookup(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
87 {
88         struct svc_fh resfh;
89         __be32 status;
90         int created = 0;
91
92         fh_init(&resfh, NFS4_FHSIZE);
93         open->op_truncate = 0;
94
95         if (open->op_create) {
96                 /*
97                  * Note: create modes (UNCHECKED,GUARDED...) are the same
98                  * in NFSv4 as in v3.
99                  */
100                 status = nfsd_create_v3(rqstp, current_fh, open->op_fname.data,
101                                         open->op_fname.len, &open->op_iattr,
102                                         &resfh, open->op_createmode,
103                                         (u32 *)open->op_verf.data,
104                                         &open->op_truncate, &created);
105
106                 /* If we ever decide to use different attrs to store the
107                  * verifier in nfsd_create_v3, then we'll need to change this
108                  */
109                 if (open->op_createmode == NFS4_CREATE_EXCLUSIVE && status == 0)
110                         open->op_bmval[1] |= (FATTR4_WORD1_TIME_ACCESS |
111                                                 FATTR4_WORD1_TIME_MODIFY);
112         } else {
113                 status = nfsd_lookup(rqstp, current_fh,
114                                      open->op_fname.data, open->op_fname.len, &resfh);
115                 fh_unlock(current_fh);
116         }
117         if (status)
118                 goto out;
119
120         set_change_info(&open->op_cinfo, current_fh);
121
122         /* set reply cache */
123         fh_dup2(current_fh, &resfh);
124         open->op_stateowner->so_replay.rp_openfh_len = resfh.fh_handle.fh_size;
125         memcpy(open->op_stateowner->so_replay.rp_openfh,
126                         &resfh.fh_handle.fh_base, resfh.fh_handle.fh_size);
127
128         if (!created)
129                 status = do_open_permission(rqstp, current_fh, open, MAY_NOP);
130
131 out:
132         fh_put(&resfh);
133         return status;
134 }
135
136 static __be32
137 do_open_fhandle(struct svc_rqst *rqstp, struct svc_fh *current_fh, struct nfsd4_open *open)
138 {
139         __be32 status;
140
141         /* Only reclaims from previously confirmed clients are valid */
142         if ((status = nfs4_check_open_reclaim(&open->op_clientid)))
143                 return status;
144
145         /* We don't know the target directory, and therefore can not
146         * set the change info
147         */
148
149         memset(&open->op_cinfo, 0, sizeof(struct nfsd4_change_info));
150
151         /* set replay cache */
152         open->op_stateowner->so_replay.rp_openfh_len = current_fh->fh_handle.fh_size;
153         memcpy(open->op_stateowner->so_replay.rp_openfh,
154                 &current_fh->fh_handle.fh_base,
155                 current_fh->fh_handle.fh_size);
156
157         open->op_truncate = (open->op_iattr.ia_valid & ATTR_SIZE) &&
158                 (open->op_iattr.ia_size == 0);
159
160         status = do_open_permission(rqstp, current_fh, open, MAY_OWNER_OVERRIDE);
161
162         return status;
163 }
164
165
166 static __be32
167 nfsd4_open(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
168            struct nfsd4_open *open)
169 {
170         __be32 status;
171         dprintk("NFSD: nfsd4_open filename %.*s op_stateowner %p\n",
172                 (int)open->op_fname.len, open->op_fname.data,
173                 open->op_stateowner);
174
175         /* This check required by spec. */
176         if (open->op_create && open->op_claim_type != NFS4_OPEN_CLAIM_NULL)
177                 return nfserr_inval;
178
179         nfs4_lock_state();
180
181         /* check seqid for replay. set nfs4_owner */
182         status = nfsd4_process_open1(open);
183         if (status == nfserr_replay_me) {
184                 struct nfs4_replay *rp = &open->op_stateowner->so_replay;
185                 fh_put(&cstate->current_fh);
186                 cstate->current_fh.fh_handle.fh_size = rp->rp_openfh_len;
187                 memcpy(&cstate->current_fh.fh_handle.fh_base, rp->rp_openfh,
188                                 rp->rp_openfh_len);
189                 status = fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
190                 if (status)
191                         dprintk("nfsd4_open: replay failed"
192                                 " restoring previous filehandle\n");
193                 else
194                         status = nfserr_replay_me;
195         }
196         if (status)
197                 goto out;
198
199         /* Openowner is now set, so sequence id will get bumped.  Now we need
200          * these checks before we do any creates: */
201         status = nfserr_grace;
202         if (nfs4_in_grace() && open->op_claim_type != NFS4_OPEN_CLAIM_PREVIOUS)
203                 goto out;
204         status = nfserr_no_grace;
205         if (!nfs4_in_grace() && open->op_claim_type == NFS4_OPEN_CLAIM_PREVIOUS)
206                 goto out;
207
208         switch (open->op_claim_type) {
209                 case NFS4_OPEN_CLAIM_DELEGATE_CUR:
210                         status = nfserr_inval;
211                         if (open->op_create)
212                                 goto out;
213                         /* fall through */
214                 case NFS4_OPEN_CLAIM_NULL:
215                         /*
216                          * (1) set CURRENT_FH to the file being opened,
217                          * creating it if necessary, (2) set open->op_cinfo,
218                          * (3) set open->op_truncate if the file is to be
219                          * truncated after opening, (4) do permission checking.
220                          */
221                         status = do_open_lookup(rqstp, &cstate->current_fh,
222                                                 open);
223                         if (status)
224                                 goto out;
225                         break;
226                 case NFS4_OPEN_CLAIM_PREVIOUS:
227                         open->op_stateowner->so_confirmed = 1;
228                         /*
229                          * The CURRENT_FH is already set to the file being
230                          * opened.  (1) set open->op_cinfo, (2) set
231                          * open->op_truncate if the file is to be truncated
232                          * after opening, (3) do permission checking.
233                         */
234                         status = do_open_fhandle(rqstp, &cstate->current_fh,
235                                                  open);
236                         if (status)
237                                 goto out;
238                         break;
239                 case NFS4_OPEN_CLAIM_DELEGATE_PREV:
240                         open->op_stateowner->so_confirmed = 1;
241                         dprintk("NFSD: unsupported OPEN claim type %d\n",
242                                 open->op_claim_type);
243                         status = nfserr_notsupp;
244                         goto out;
245                 default:
246                         dprintk("NFSD: Invalid OPEN claim type %d\n",
247                                 open->op_claim_type);
248                         status = nfserr_inval;
249                         goto out;
250         }
251         /*
252          * nfsd4_process_open2() does the actual opening of the file.  If
253          * successful, it (1) truncates the file if open->op_truncate was
254          * set, (2) sets open->op_stateid, (3) sets open->op_delegation.
255          */
256         status = nfsd4_process_open2(rqstp, &cstate->current_fh, open);
257 out:
258         if (open->op_stateowner) {
259                 nfs4_get_stateowner(open->op_stateowner);
260                 cstate->replay_owner = open->op_stateowner;
261         }
262         nfs4_unlock_state();
263         return status;
264 }
265
266 /*
267  * filehandle-manipulating ops.
268  */
269 static __be32
270 nfsd4_getfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
271             struct svc_fh **getfh)
272 {
273         if (!cstate->current_fh.fh_dentry)
274                 return nfserr_nofilehandle;
275
276         *getfh = &cstate->current_fh;
277         return nfs_ok;
278 }
279
280 static __be32
281 nfsd4_putfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
282             struct nfsd4_putfh *putfh)
283 {
284         fh_put(&cstate->current_fh);
285         cstate->current_fh.fh_handle.fh_size = putfh->pf_fhlen;
286         memcpy(&cstate->current_fh.fh_handle.fh_base, putfh->pf_fhval,
287                putfh->pf_fhlen);
288         return fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
289 }
290
291 static __be32
292 nfsd4_putrootfh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
293                 void *arg)
294 {
295         __be32 status;
296
297         fh_put(&cstate->current_fh);
298         status = exp_pseudoroot(rqstp, &cstate->current_fh);
299         return status;
300 }
301
302 static __be32
303 nfsd4_restorefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
304                 void *arg)
305 {
306         if (!cstate->save_fh.fh_dentry)
307                 return nfserr_restorefh;
308
309         fh_dup2(&cstate->current_fh, &cstate->save_fh);
310         return nfs_ok;
311 }
312
313 static __be32
314 nfsd4_savefh(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
315              void *arg)
316 {
317         if (!cstate->current_fh.fh_dentry)
318                 return nfserr_nofilehandle;
319
320         fh_dup2(&cstate->save_fh, &cstate->current_fh);
321         return nfs_ok;
322 }
323
324 /*
325  * misc nfsv4 ops
326  */
327 static __be32
328 nfsd4_access(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
329              struct nfsd4_access *access)
330 {
331         if (access->ac_req_access & ~NFS3_ACCESS_FULL)
332                 return nfserr_inval;
333
334         access->ac_resp_access = access->ac_req_access;
335         return nfsd_access(rqstp, &cstate->current_fh, &access->ac_resp_access,
336                            &access->ac_supported);
337 }
338
339 static __be32
340 nfsd4_commit(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
341              struct nfsd4_commit *commit)
342 {
343         __be32 status;
344
345         u32 *p = (u32 *)commit->co_verf.data;
346         *p++ = nfssvc_boot.tv_sec;
347         *p++ = nfssvc_boot.tv_usec;
348
349         status = nfsd_commit(rqstp, &cstate->current_fh, commit->co_offset,
350                              commit->co_count);
351         if (status == nfserr_symlink)
352                 status = nfserr_inval;
353         return status;
354 }
355
356 static __be32
357 nfsd4_create(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
358              struct nfsd4_create *create)
359 {
360         struct svc_fh resfh;
361         __be32 status;
362         dev_t rdev;
363
364         fh_init(&resfh, NFS4_FHSIZE);
365
366         status = fh_verify(rqstp, &cstate->current_fh, S_IFDIR, MAY_CREATE);
367         if (status == nfserr_symlink)
368                 status = nfserr_notdir;
369         if (status)
370                 return status;
371
372         switch (create->cr_type) {
373         case NF4LNK:
374                 /* ugh! we have to null-terminate the linktext, or
375                  * vfs_symlink() will choke.  it is always safe to
376                  * null-terminate by brute force, since at worst we
377                  * will overwrite the first byte of the create namelen
378                  * in the XDR buffer, which has already been extracted
379                  * during XDR decode.
380                  */
381                 create->cr_linkname[create->cr_linklen] = 0;
382
383                 status = nfsd_symlink(rqstp, &cstate->current_fh,
384                                       create->cr_name, create->cr_namelen,
385                                       create->cr_linkname, create->cr_linklen,
386                                       &resfh, &create->cr_iattr);
387                 break;
388
389         case NF4BLK:
390                 rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
391                 if (MAJOR(rdev) != create->cr_specdata1 ||
392                     MINOR(rdev) != create->cr_specdata2)
393                         return nfserr_inval;
394                 status = nfsd_create(rqstp, &cstate->current_fh,
395                                      create->cr_name, create->cr_namelen,
396                                      &create->cr_iattr, S_IFBLK, rdev, &resfh);
397                 break;
398
399         case NF4CHR:
400                 rdev = MKDEV(create->cr_specdata1, create->cr_specdata2);
401                 if (MAJOR(rdev) != create->cr_specdata1 ||
402                     MINOR(rdev) != create->cr_specdata2)
403                         return nfserr_inval;
404                 status = nfsd_create(rqstp, &cstate->current_fh,
405                                      create->cr_name, create->cr_namelen,
406                                      &create->cr_iattr,S_IFCHR, rdev, &resfh);
407                 break;
408
409         case NF4SOCK:
410                 status = nfsd_create(rqstp, &cstate->current_fh,
411                                      create->cr_name, create->cr_namelen,
412                                      &create->cr_iattr, S_IFSOCK, 0, &resfh);
413                 break;
414
415         case NF4FIFO:
416                 status = nfsd_create(rqstp, &cstate->current_fh,
417                                      create->cr_name, create->cr_namelen,
418                                      &create->cr_iattr, S_IFIFO, 0, &resfh);
419                 break;
420
421         case NF4DIR:
422                 create->cr_iattr.ia_valid &= ~ATTR_SIZE;
423                 status = nfsd_create(rqstp, &cstate->current_fh,
424                                      create->cr_name, create->cr_namelen,
425                                      &create->cr_iattr, S_IFDIR, 0, &resfh);
426                 break;
427
428         default:
429                 status = nfserr_badtype;
430         }
431
432         if (!status) {
433                 fh_unlock(&cstate->current_fh);
434                 set_change_info(&create->cr_cinfo, &cstate->current_fh);
435                 fh_dup2(&cstate->current_fh, &resfh);
436         }
437
438         fh_put(&resfh);
439         return status;
440 }
441
442 static __be32
443 nfsd4_getattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
444               struct nfsd4_getattr *getattr)
445 {
446         __be32 status;
447
448         status = fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
449         if (status)
450                 return status;
451
452         if (getattr->ga_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
453                 return nfserr_inval;
454
455         getattr->ga_bmval[0] &= NFSD_SUPPORTED_ATTRS_WORD0;
456         getattr->ga_bmval[1] &= NFSD_SUPPORTED_ATTRS_WORD1;
457
458         getattr->ga_fhp = &cstate->current_fh;
459         return nfs_ok;
460 }
461
462 static __be32
463 nfsd4_link(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
464            struct nfsd4_link *link)
465 {
466         __be32 status = nfserr_nofilehandle;
467
468         if (!cstate->save_fh.fh_dentry)
469                 return status;
470         status = nfsd_link(rqstp, &cstate->current_fh,
471                            link->li_name, link->li_namelen, &cstate->save_fh);
472         if (!status)
473                 set_change_info(&link->li_cinfo, &cstate->current_fh);
474         return status;
475 }
476
477 static __be32
478 nfsd4_lookupp(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
479               void *arg)
480 {
481         struct svc_fh tmp_fh;
482         __be32 ret;
483
484         fh_init(&tmp_fh, NFS4_FHSIZE);
485         ret = exp_pseudoroot(rqstp, &tmp_fh);
486         if (ret)
487                 return ret;
488         if (tmp_fh.fh_dentry == cstate->current_fh.fh_dentry) {
489                 fh_put(&tmp_fh);
490                 return nfserr_noent;
491         }
492         fh_put(&tmp_fh);
493         return nfsd_lookup(rqstp, &cstate->current_fh,
494                            "..", 2, &cstate->current_fh);
495 }
496
497 static __be32
498 nfsd4_lookup(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
499              struct nfsd4_lookup *lookup)
500 {
501         return nfsd_lookup(rqstp, &cstate->current_fh,
502                            lookup->lo_name, lookup->lo_len,
503                            &cstate->current_fh);
504 }
505
506 static __be32
507 nfsd4_read(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
508            struct nfsd4_read *read)
509 {
510         __be32 status;
511
512         /* no need to check permission - this will be done in nfsd_read() */
513
514         read->rd_filp = NULL;
515         if (read->rd_offset >= OFFSET_MAX)
516                 return nfserr_inval;
517
518         nfs4_lock_state();
519         /* check stateid */
520         if ((status = nfs4_preprocess_stateid_op(&cstate->current_fh,
521                                 &read->rd_stateid,
522                                 CHECK_FH | RD_STATE, &read->rd_filp))) {
523                 dprintk("NFSD: nfsd4_read: couldn't process stateid!\n");
524                 goto out;
525         }
526         if (read->rd_filp)
527                 get_file(read->rd_filp);
528         status = nfs_ok;
529 out:
530         nfs4_unlock_state();
531         read->rd_rqstp = rqstp;
532         read->rd_fhp = &cstate->current_fh;
533         return status;
534 }
535
536 static __be32
537 nfsd4_readdir(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
538               struct nfsd4_readdir *readdir)
539 {
540         u64 cookie = readdir->rd_cookie;
541         static const nfs4_verifier zeroverf;
542
543         /* no need to check permission - this will be done in nfsd_readdir() */
544
545         if (readdir->rd_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1)
546                 return nfserr_inval;
547
548         readdir->rd_bmval[0] &= NFSD_SUPPORTED_ATTRS_WORD0;
549         readdir->rd_bmval[1] &= NFSD_SUPPORTED_ATTRS_WORD1;
550
551         if ((cookie > ~(u32)0) || (cookie == 1) || (cookie == 2) ||
552             (cookie == 0 && memcmp(readdir->rd_verf.data, zeroverf.data, NFS4_VERIFIER_SIZE)))
553                 return nfserr_bad_cookie;
554
555         readdir->rd_rqstp = rqstp;
556         readdir->rd_fhp = &cstate->current_fh;
557         return nfs_ok;
558 }
559
560 static __be32
561 nfsd4_readlink(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
562                struct nfsd4_readlink *readlink)
563 {
564         readlink->rl_rqstp = rqstp;
565         readlink->rl_fhp = &cstate->current_fh;
566         return nfs_ok;
567 }
568
569 static __be32
570 nfsd4_remove(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
571              struct nfsd4_remove *remove)
572 {
573         __be32 status;
574
575         if (nfs4_in_grace())
576                 return nfserr_grace;
577         status = nfsd_unlink(rqstp, &cstate->current_fh, 0,
578                              remove->rm_name, remove->rm_namelen);
579         if (status == nfserr_symlink)
580                 return nfserr_notdir;
581         if (!status) {
582                 fh_unlock(&cstate->current_fh);
583                 set_change_info(&remove->rm_cinfo, &cstate->current_fh);
584         }
585         return status;
586 }
587
588 static __be32
589 nfsd4_rename(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
590              struct nfsd4_rename *rename)
591 {
592         __be32 status = nfserr_nofilehandle;
593
594         if (!cstate->save_fh.fh_dentry)
595                 return status;
596         if (nfs4_in_grace() && !(cstate->save_fh.fh_export->ex_flags
597                                         & NFSEXP_NOSUBTREECHECK))
598                 return nfserr_grace;
599         status = nfsd_rename(rqstp, &cstate->save_fh, rename->rn_sname,
600                              rename->rn_snamelen, &cstate->current_fh,
601                              rename->rn_tname, rename->rn_tnamelen);
602
603         /* the underlying filesystem returns different error's than required
604          * by NFSv4. both save_fh and current_fh have been verified.. */
605         if (status == nfserr_isdir)
606                 status = nfserr_exist;
607         else if ((status == nfserr_notdir) &&
608                   (S_ISDIR(cstate->save_fh.fh_dentry->d_inode->i_mode) &&
609                    S_ISDIR(cstate->current_fh.fh_dentry->d_inode->i_mode)))
610                 status = nfserr_exist;
611         else if (status == nfserr_symlink)
612                 status = nfserr_notdir;
613
614         if (!status) {
615                 set_change_info(&rename->rn_sinfo, &cstate->current_fh);
616                 set_change_info(&rename->rn_tinfo, &cstate->save_fh);
617         }
618         return status;
619 }
620
621 static __be32
622 nfsd4_secinfo(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
623               struct nfsd4_secinfo *secinfo)
624 {
625         struct svc_fh resfh;
626         struct svc_export *exp;
627         struct dentry *dentry;
628         __be32 err;
629
630         fh_init(&resfh, NFS4_FHSIZE);
631         err = nfsd_lookup_dentry(rqstp, &cstate->current_fh,
632                                     secinfo->si_name, secinfo->si_namelen,
633                                     &exp, &dentry);
634         if (err)
635                 return err;
636         if (dentry->d_inode == NULL) {
637                 exp_put(exp);
638                 err = nfserr_noent;
639         } else
640                 secinfo->si_exp = exp;
641         dput(dentry);
642         return err;
643 }
644
645 static __be32
646 nfsd4_setattr(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
647               struct nfsd4_setattr *setattr)
648 {
649         __be32 status = nfs_ok;
650
651         if (setattr->sa_iattr.ia_valid & ATTR_SIZE) {
652                 nfs4_lock_state();
653                 status = nfs4_preprocess_stateid_op(&cstate->current_fh,
654                         &setattr->sa_stateid, CHECK_FH | WR_STATE, NULL);
655                 nfs4_unlock_state();
656                 if (status) {
657                         dprintk("NFSD: nfsd4_setattr: couldn't process stateid!\n");
658                         return status;
659                 }
660         }
661         status = nfs_ok;
662         if (setattr->sa_acl != NULL)
663                 status = nfsd4_set_nfs4_acl(rqstp, &cstate->current_fh,
664                                             setattr->sa_acl);
665         if (status)
666                 return status;
667         status = nfsd_setattr(rqstp, &cstate->current_fh, &setattr->sa_iattr,
668                                 0, (time_t)0);
669         return status;
670 }
671
672 static __be32
673 nfsd4_write(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
674             struct nfsd4_write *write)
675 {
676         stateid_t *stateid = &write->wr_stateid;
677         struct file *filp = NULL;
678         u32 *p;
679         __be32 status = nfs_ok;
680
681         /* no need to check permission - this will be done in nfsd_write() */
682
683         if (write->wr_offset >= OFFSET_MAX)
684                 return nfserr_inval;
685
686         nfs4_lock_state();
687         status = nfs4_preprocess_stateid_op(&cstate->current_fh, stateid,
688                                         CHECK_FH | WR_STATE, &filp);
689         if (filp)
690                 get_file(filp);
691         nfs4_unlock_state();
692
693         if (status) {
694                 dprintk("NFSD: nfsd4_write: couldn't process stateid!\n");
695                 return status;
696         }
697
698         write->wr_bytes_written = write->wr_buflen;
699         write->wr_how_written = write->wr_stable_how;
700         p = (u32 *)write->wr_verifier.data;
701         *p++ = nfssvc_boot.tv_sec;
702         *p++ = nfssvc_boot.tv_usec;
703
704         status =  nfsd_write(rqstp, &cstate->current_fh, filp,
705                              write->wr_offset, rqstp->rq_vec, write->wr_vlen,
706                              write->wr_buflen, &write->wr_how_written);
707         if (filp)
708                 fput(filp);
709
710         if (status == nfserr_symlink)
711                 status = nfserr_inval;
712         return status;
713 }
714
715 /* This routine never returns NFS_OK!  If there are no other errors, it
716  * will return NFSERR_SAME or NFSERR_NOT_SAME depending on whether the
717  * attributes matched.  VERIFY is implemented by mapping NFSERR_SAME
718  * to NFS_OK after the call; NVERIFY by mapping NFSERR_NOT_SAME to NFS_OK.
719  */
720 static __be32
721 _nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
722              struct nfsd4_verify *verify)
723 {
724         __be32 *buf, *p;
725         int count;
726         __be32 status;
727
728         status = fh_verify(rqstp, &cstate->current_fh, 0, MAY_NOP);
729         if (status)
730                 return status;
731
732         if ((verify->ve_bmval[0] & ~NFSD_SUPPORTED_ATTRS_WORD0)
733             || (verify->ve_bmval[1] & ~NFSD_SUPPORTED_ATTRS_WORD1))
734                 return nfserr_attrnotsupp;
735         if ((verify->ve_bmval[0] & FATTR4_WORD0_RDATTR_ERROR)
736             || (verify->ve_bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1))
737                 return nfserr_inval;
738         if (verify->ve_attrlen & 3)
739                 return nfserr_inval;
740
741         /* count in words:
742          *   bitmap_len(1) + bitmap(2) + attr_len(1) = 4
743          */
744         count = 4 + (verify->ve_attrlen >> 2);
745         buf = kmalloc(count << 2, GFP_KERNEL);
746         if (!buf)
747                 return nfserr_resource;
748
749         status = nfsd4_encode_fattr(&cstate->current_fh,
750                                     cstate->current_fh.fh_export,
751                                     cstate->current_fh.fh_dentry, buf,
752                                     &count, verify->ve_bmval,
753                                     rqstp, 0);
754
755         /* this means that nfsd4_encode_fattr() ran out of space */
756         if (status == nfserr_resource && count == 0)
757                 status = nfserr_not_same;
758         if (status)
759                 goto out_kfree;
760
761         p = buf + 3;
762         status = nfserr_not_same;
763         if (ntohl(*p++) != verify->ve_attrlen)
764                 goto out_kfree;
765         if (!memcmp(p, verify->ve_attrval, verify->ve_attrlen))
766                 status = nfserr_same;
767
768 out_kfree:
769         kfree(buf);
770         return status;
771 }
772
773 static __be32
774 nfsd4_nverify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
775               struct nfsd4_verify *verify)
776 {
777         __be32 status;
778
779         status = _nfsd4_verify(rqstp, cstate, verify);
780         return status == nfserr_not_same ? nfs_ok : status;
781 }
782
783 static __be32
784 nfsd4_verify(struct svc_rqst *rqstp, struct nfsd4_compound_state *cstate,
785              struct nfsd4_verify *verify)
786 {
787         __be32 status;
788
789         status = _nfsd4_verify(rqstp, cstate, verify);
790         return status == nfserr_same ? nfs_ok : status;
791 }
792
793 /*
794  * NULL call.
795  */
796 static __be32
797 nfsd4_proc_null(struct svc_rqst *rqstp, void *argp, void *resp)
798 {
799         return nfs_ok;
800 }
801
802 static inline void nfsd4_increment_op_stats(u32 opnum)
803 {
804         if (opnum >= FIRST_NFS4_OP && opnum <= LAST_NFS4_OP)
805                 nfsdstats.nfs4_opcount[opnum]++;
806 }
807
808 static void cstate_free(struct nfsd4_compound_state *cstate)
809 {
810         if (cstate == NULL)
811                 return;
812         fh_put(&cstate->current_fh);
813         fh_put(&cstate->save_fh);
814         BUG_ON(cstate->replay_owner);
815         kfree(cstate);
816 }
817
818 static struct nfsd4_compound_state *cstate_alloc(void)
819 {
820         struct nfsd4_compound_state *cstate;
821
822         cstate = kmalloc(sizeof(struct nfsd4_compound_state), GFP_KERNEL);
823         if (cstate == NULL)
824                 return NULL;
825         fh_init(&cstate->current_fh, NFS4_FHSIZE);
826         fh_init(&cstate->save_fh, NFS4_FHSIZE);
827         cstate->replay_owner = NULL;
828         return cstate;
829 }
830
831 typedef __be32(*nfsd4op_func)(struct svc_rqst *, struct nfsd4_compound_state *,
832                               void *);
833
834 struct nfsd4_operation {
835         nfsd4op_func op_func;
836         u32 op_flags;
837 /* Most ops require a valid current filehandle; a few don't: */
838 #define ALLOWED_WITHOUT_FH 1
839 /* GETATTR and ops not listed as returning NFS4ERR_MOVED: */
840 #define ALLOWED_ON_ABSENT_FS 2
841 };
842
843 static struct nfsd4_operation nfsd4_ops[];
844
845 /*
846  * COMPOUND call.
847  */
848 static __be32
849 nfsd4_proc_compound(struct svc_rqst *rqstp,
850                     struct nfsd4_compoundargs *args,
851                     struct nfsd4_compoundres *resp)
852 {
853         struct nfsd4_op *op;
854         struct nfsd4_operation *opdesc;
855         struct nfsd4_compound_state *cstate = NULL;
856         int             slack_bytes;
857         __be32          status;
858
859         status = nfserr_resource;
860         cstate = cstate_alloc();
861         if (cstate == NULL)
862                 goto out;
863
864         resp->xbuf = &rqstp->rq_res;
865         resp->p = rqstp->rq_res.head[0].iov_base + rqstp->rq_res.head[0].iov_len;
866         resp->tagp = resp->p;
867         /* reserve space for: taglen, tag, and opcnt */
868         resp->p += 2 + XDR_QUADLEN(args->taglen);
869         resp->end = rqstp->rq_res.head[0].iov_base + PAGE_SIZE;
870         resp->taglen = args->taglen;
871         resp->tag = args->tag;
872         resp->opcnt = 0;
873         resp->rqstp = rqstp;
874
875         /*
876          * According to RFC3010, this takes precedence over all other errors.
877          */
878         status = nfserr_minor_vers_mismatch;
879         if (args->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
880                 goto out;
881
882         status = nfs_ok;
883         while (!status && resp->opcnt < args->opcnt) {
884                 op = &args->ops[resp->opcnt++];
885
886                 dprintk("nfsv4 compound op #%d: %d\n", resp->opcnt, op->opnum);
887
888                 /*
889                  * The XDR decode routines may have pre-set op->status;
890                  * for example, if there is a miscellaneous XDR error
891                  * it will be set to nfserr_bad_xdr.
892                  */
893                 if (op->status)
894                         goto encode_op;
895
896                 /* We must be able to encode a successful response to
897                  * this operation, with enough room left over to encode a
898                  * failed response to the next operation.  If we don't
899                  * have enough room, fail with ERR_RESOURCE.
900                  */
901                 slack_bytes = (char *)resp->end - (char *)resp->p;
902                 if (slack_bytes < COMPOUND_SLACK_SPACE
903                                 + COMPOUND_ERR_SLACK_SPACE) {
904                         BUG_ON(slack_bytes < COMPOUND_ERR_SLACK_SPACE);
905                         op->status = nfserr_resource;
906                         goto encode_op;
907                 }
908
909                 opdesc = &nfsd4_ops[op->opnum];
910
911                 if (!cstate->current_fh.fh_dentry) {
912                         if (!(opdesc->op_flags & ALLOWED_WITHOUT_FH)) {
913                                 op->status = nfserr_nofilehandle;
914                                 goto encode_op;
915                         }
916                 } else if (cstate->current_fh.fh_export->ex_fslocs.migrated &&
917                           !(opdesc->op_flags & ALLOWED_ON_ABSENT_FS)) {
918                         op->status = nfserr_moved;
919                         goto encode_op;
920                 }
921
922                 if (opdesc->op_func)
923                         op->status = opdesc->op_func(rqstp, cstate, &op->u);
924                 else
925                         BUG_ON(op->status == nfs_ok);
926
927 encode_op:
928                 if (op->status == nfserr_replay_me) {
929                         op->replay = &cstate->replay_owner->so_replay;
930                         nfsd4_encode_replay(resp, op);
931                         status = op->status = op->replay->rp_status;
932                 } else {
933                         nfsd4_encode_operation(resp, op);
934                         status = op->status;
935                 }
936                 if (cstate->replay_owner) {
937                         nfs4_put_stateowner(cstate->replay_owner);
938                         cstate->replay_owner = NULL;
939                 }
940                 /* XXX Ugh, we need to get rid of this kind of special case: */
941                 if (op->opnum == OP_READ && op->u.read.rd_filp)
942                         fput(op->u.read.rd_filp);
943
944                 nfsd4_increment_op_stats(op->opnum);
945         }
946
947 out:
948         nfsd4_release_compoundargs(args);
949         cstate_free(cstate);
950         return status;
951 }
952
953 static struct nfsd4_operation nfsd4_ops[OP_RELEASE_LOCKOWNER+1] = {
954         [OP_ACCESS] = {
955                 .op_func = (nfsd4op_func)nfsd4_access,
956         },
957         [OP_CLOSE] = {
958                 .op_func = (nfsd4op_func)nfsd4_close,
959         },
960         [OP_COMMIT] = {
961                 .op_func = (nfsd4op_func)nfsd4_commit,
962         },
963         [OP_CREATE] = {
964                 .op_func = (nfsd4op_func)nfsd4_create,
965         },
966         [OP_DELEGRETURN] = {
967                 .op_func = (nfsd4op_func)nfsd4_delegreturn,
968         },
969         [OP_GETATTR] = {
970                 .op_func = (nfsd4op_func)nfsd4_getattr,
971                 .op_flags = ALLOWED_ON_ABSENT_FS,
972         },
973         [OP_GETFH] = {
974                 .op_func = (nfsd4op_func)nfsd4_getfh,
975         },
976         [OP_LINK] = {
977                 .op_func = (nfsd4op_func)nfsd4_link,
978         },
979         [OP_LOCK] = {
980                 .op_func = (nfsd4op_func)nfsd4_lock,
981         },
982         [OP_LOCKT] = {
983                 .op_func = (nfsd4op_func)nfsd4_lockt,
984         },
985         [OP_LOCKU] = {
986                 .op_func = (nfsd4op_func)nfsd4_locku,
987         },
988         [OP_LOOKUP] = {
989                 .op_func = (nfsd4op_func)nfsd4_lookup,
990         },
991         [OP_LOOKUPP] = {
992                 .op_func = (nfsd4op_func)nfsd4_lookupp,
993         },
994         [OP_NVERIFY] = {
995                 .op_func = (nfsd4op_func)nfsd4_nverify,
996         },
997         [OP_OPEN] = {
998                 .op_func = (nfsd4op_func)nfsd4_open,
999         },
1000         [OP_OPEN_CONFIRM] = {
1001                 .op_func = (nfsd4op_func)nfsd4_open_confirm,
1002         },
1003         [OP_OPEN_DOWNGRADE] = {
1004                 .op_func = (nfsd4op_func)nfsd4_open_downgrade,
1005         },
1006         [OP_PUTFH] = {
1007                 .op_func = (nfsd4op_func)nfsd4_putfh,
1008                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1009         },
1010         [OP_PUTPUBFH] = {
1011                 /* unsupported; just for future reference: */
1012                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1013         },
1014         [OP_PUTROOTFH] = {
1015                 .op_func = (nfsd4op_func)nfsd4_putrootfh,
1016                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1017         },
1018         [OP_READ] = {
1019                 .op_func = (nfsd4op_func)nfsd4_read,
1020         },
1021         [OP_READDIR] = {
1022                 .op_func = (nfsd4op_func)nfsd4_readdir,
1023         },
1024         [OP_READLINK] = {
1025                 .op_func = (nfsd4op_func)nfsd4_readlink,
1026         },
1027         [OP_REMOVE] = {
1028                 .op_func = (nfsd4op_func)nfsd4_remove,
1029         },
1030         [OP_RENAME] = {
1031                 .op_func = (nfsd4op_func)nfsd4_rename,
1032         },
1033         [OP_RENEW] = {
1034                 .op_func = (nfsd4op_func)nfsd4_renew,
1035                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1036         },
1037         [OP_RESTOREFH] = {
1038                 .op_func = (nfsd4op_func)nfsd4_restorefh,
1039                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1040         },
1041         [OP_SAVEFH] = {
1042                 .op_func = (nfsd4op_func)nfsd4_savefh,
1043         },
1044         [OP_SECINFO] = {
1045                 .op_func = (nfsd4op_func)nfsd4_secinfo,
1046         },
1047         [OP_SETATTR] = {
1048                 .op_func = (nfsd4op_func)nfsd4_setattr,
1049         },
1050         [OP_SETCLIENTID] = {
1051                 .op_func = (nfsd4op_func)nfsd4_setclientid,
1052                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1053         },
1054         [OP_SETCLIENTID_CONFIRM] = {
1055                 .op_func = (nfsd4op_func)nfsd4_setclientid_confirm,
1056                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1057         },
1058         [OP_VERIFY] = {
1059                 .op_func = (nfsd4op_func)nfsd4_verify,
1060         },
1061         [OP_WRITE] = {
1062                 .op_func = (nfsd4op_func)nfsd4_write,
1063         },
1064         [OP_RELEASE_LOCKOWNER] = {
1065                 .op_func = (nfsd4op_func)nfsd4_release_lockowner,
1066                 .op_flags = ALLOWED_WITHOUT_FH | ALLOWED_ON_ABSENT_FS,
1067         },
1068 };
1069
1070 #define nfs4svc_decode_voidargs         NULL
1071 #define nfs4svc_release_void            NULL
1072 #define nfsd4_voidres                   nfsd4_voidargs
1073 #define nfs4svc_release_compound        NULL
1074 struct nfsd4_voidargs { int dummy; };
1075
1076 #define PROC(name, argt, rest, relt, cache, respsize)   \
1077  { (svc_procfunc) nfsd4_proc_##name,            \
1078    (kxdrproc_t) nfs4svc_decode_##argt##args,    \
1079    (kxdrproc_t) nfs4svc_encode_##rest##res,     \
1080    (kxdrproc_t) nfs4svc_release_##relt,         \
1081    sizeof(struct nfsd4_##argt##args),           \
1082    sizeof(struct nfsd4_##rest##res),            \
1083    0,                                           \
1084    cache,                                       \
1085    respsize,                                    \
1086  }
1087
1088 /*
1089  * TODO: At the present time, the NFSv4 server does not do XID caching
1090  * of requests.  Implementing XID caching would not be a serious problem,
1091  * although it would require a mild change in interfaces since one
1092  * doesn't know whether an NFSv4 request is idempotent until after the
1093  * XDR decode.  However, XID caching totally confuses pynfs (Peter
1094  * Astrand's regression testsuite for NFSv4 servers), which reuses
1095  * XID's liberally, so I've left it unimplemented until pynfs generates
1096  * better XID's.
1097  */
1098 static struct svc_procedure             nfsd_procedures4[2] = {
1099   PROC(null,     void,          void,           void,     RC_NOCACHE, 1),
1100   PROC(compound, compound,      compound,       compound, RC_NOCACHE, NFSD_BUFSIZE/4)
1101 };
1102
1103 struct svc_version      nfsd_version4 = {
1104                 .vs_vers        = 4,
1105                 .vs_nproc       = 2,
1106                 .vs_proc        = nfsd_procedures4,
1107                 .vs_dispatch    = nfsd_dispatch,
1108                 .vs_xdrsize     = NFS4_SVC_XDRSIZE,
1109 };
1110
1111 /*
1112  * Local variables:
1113  *  c-basic-offset: 8
1114  * End:
1115  */