1 /*
2 * XDR support for nfsd
3 *
4 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
5 */
6
7 #include "vfs.h"
8 #include "xdr.h"
9 #include "auth.h"
10
11 #define NFSDDBG_FACILITY NFSDDBG_XDR
12
13 /*
14 * Mapping of S_IF* types to NFS file types
15 */
16 static u32 nfs_ftypes[] = {
17 NFNON, NFCHR, NFCHR, NFBAD,
18 NFDIR, NFBAD, NFBLK, NFBAD,
19 NFREG, NFBAD, NFLNK, NFBAD,
20 NFSOCK, NFBAD, NFLNK, NFBAD,
21 };
22
23
24 /*
25 * XDR functions for basic NFS types
26 */
27 static __be32 *
decode_fh(__be32 * p,struct svc_fh * fhp)28 decode_fh(__be32 *p, struct svc_fh *fhp)
29 {
30 fh_init(fhp, NFS_FHSIZE);
31 memcpy(&fhp->fh_handle.fh_base, p, NFS_FHSIZE);
32 fhp->fh_handle.fh_size = NFS_FHSIZE;
33
34 /* FIXME: Look up export pointer here and verify
35 * Sun Secure RPC if requested */
36 return p + (NFS_FHSIZE >> 2);
37 }
38
39 /* Helper function for NFSv2 ACL code */
nfs2svc_decode_fh(__be32 * p,struct svc_fh * fhp)40 __be32 *nfs2svc_decode_fh(__be32 *p, struct svc_fh *fhp)
41 {
42 return decode_fh(p, fhp);
43 }
44
45 static __be32 *
encode_fh(__be32 * p,struct svc_fh * fhp)46 encode_fh(__be32 *p, struct svc_fh *fhp)
47 {
48 memcpy(p, &fhp->fh_handle.fh_base, NFS_FHSIZE);
49 return p + (NFS_FHSIZE>> 2);
50 }
51
52 /*
53 * Decode a file name and make sure that the path contains
54 * no slashes or null bytes.
55 */
56 static __be32 *
decode_filename(__be32 * p,char ** namp,unsigned int * lenp)57 decode_filename(__be32 *p, char **namp, unsigned int *lenp)
58 {
59 char *name;
60 unsigned int i;
61
62 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXNAMLEN)) != NULL) {
63 for (i = 0, name = *namp; i < *lenp; i++, name++) {
64 if (*name == '\0' || *name == '/')
65 return NULL;
66 }
67 }
68
69 return p;
70 }
71
72 static __be32 *
decode_pathname(__be32 * p,char ** namp,unsigned int * lenp)73 decode_pathname(__be32 *p, char **namp, unsigned int *lenp)
74 {
75 char *name;
76 unsigned int i;
77
78 if ((p = xdr_decode_string_inplace(p, namp, lenp, NFS_MAXPATHLEN)) != NULL) {
79 for (i = 0, name = *namp; i < *lenp; i++, name++) {
80 if (*name == '\0')
81 return NULL;
82 }
83 }
84
85 return p;
86 }
87
88 static __be32 *
decode_sattr(__be32 * p,struct iattr * iap)89 decode_sattr(__be32 *p, struct iattr *iap)
90 {
91 u32 tmp, tmp1;
92
93 iap->ia_valid = 0;
94
95 /* Sun client bug compatibility check: some sun clients seem to
96 * put 0xffff in the mode field when they mean 0xffffffff.
97 * Quoting the 4.4BSD nfs server code: Nah nah nah nah na nah.
98 */
99 if ((tmp = ntohl(*p++)) != (u32)-1 && tmp != 0xffff) {
100 iap->ia_valid |= ATTR_MODE;
101 iap->ia_mode = tmp;
102 }
103 if ((tmp = ntohl(*p++)) != (u32)-1) {
104 iap->ia_uid = make_kuid(&init_user_ns, tmp);
105 if (uid_valid(iap->ia_uid))
106 iap->ia_valid |= ATTR_UID;
107 }
108 if ((tmp = ntohl(*p++)) != (u32)-1) {
109 iap->ia_gid = make_kgid(&init_user_ns, tmp);
110 if (gid_valid(iap->ia_gid))
111 iap->ia_valid |= ATTR_GID;
112 }
113 if ((tmp = ntohl(*p++)) != (u32)-1) {
114 iap->ia_valid |= ATTR_SIZE;
115 iap->ia_size = tmp;
116 }
117 tmp = ntohl(*p++); tmp1 = ntohl(*p++);
118 if (tmp != (u32)-1 && tmp1 != (u32)-1) {
119 iap->ia_valid |= ATTR_ATIME | ATTR_ATIME_SET;
120 iap->ia_atime.tv_sec = tmp;
121 iap->ia_atime.tv_nsec = tmp1 * 1000;
122 }
123 tmp = ntohl(*p++); tmp1 = ntohl(*p++);
124 if (tmp != (u32)-1 && tmp1 != (u32)-1) {
125 iap->ia_valid |= ATTR_MTIME | ATTR_MTIME_SET;
126 iap->ia_mtime.tv_sec = tmp;
127 iap->ia_mtime.tv_nsec = tmp1 * 1000;
128 /*
129 * Passing the invalid value useconds=1000000 for mtime
130 * is a Sun convention for "set both mtime and atime to
131 * current server time". It's needed to make permissions
132 * checks for the "touch" program across v2 mounts to
133 * Solaris and Irix boxes work correctly. See description of
134 * sattr in section 6.1 of "NFS Illustrated" by
135 * Brent Callaghan, Addison-Wesley, ISBN 0-201-32750-5
136 */
137 if (tmp1 == 1000000)
138 iap->ia_valid &= ~(ATTR_ATIME_SET|ATTR_MTIME_SET);
139 }
140 return p;
141 }
142
143 static __be32 *
encode_fattr(struct svc_rqst * rqstp,__be32 * p,struct svc_fh * fhp,struct kstat * stat)144 encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp,
145 struct kstat *stat)
146 {
147 struct dentry *dentry = fhp->fh_dentry;
148 int type;
149 struct timespec time;
150 u32 f;
151
152 type = (stat->mode & S_IFMT);
153
154 *p++ = htonl(nfs_ftypes[type >> 12]);
155 *p++ = htonl((u32) stat->mode);
156 *p++ = htonl((u32) stat->nlink);
157 *p++ = htonl((u32) from_kuid(&init_user_ns, stat->uid));
158 *p++ = htonl((u32) from_kgid(&init_user_ns, stat->gid));
159
160 if (S_ISLNK(type) && stat->size > NFS_MAXPATHLEN) {
161 *p++ = htonl(NFS_MAXPATHLEN);
162 } else {
163 *p++ = htonl((u32) stat->size);
164 }
165 *p++ = htonl((u32) stat->blksize);
166 if (S_ISCHR(type) || S_ISBLK(type))
167 *p++ = htonl(new_encode_dev(stat->rdev));
168 else
169 *p++ = htonl(0xffffffff);
170 *p++ = htonl((u32) stat->blocks);
171 switch (fsid_source(fhp)) {
172 default:
173 case FSIDSOURCE_DEV:
174 *p++ = htonl(new_encode_dev(stat->dev));
175 break;
176 case FSIDSOURCE_FSID:
177 *p++ = htonl((u32) fhp->fh_export->ex_fsid);
178 break;
179 case FSIDSOURCE_UUID:
180 f = ((u32*)fhp->fh_export->ex_uuid)[0];
181 f ^= ((u32*)fhp->fh_export->ex_uuid)[1];
182 f ^= ((u32*)fhp->fh_export->ex_uuid)[2];
183 f ^= ((u32*)fhp->fh_export->ex_uuid)[3];
184 *p++ = htonl(f);
185 break;
186 }
187 *p++ = htonl((u32) stat->ino);
188 *p++ = htonl((u32) stat->atime.tv_sec);
189 *p++ = htonl(stat->atime.tv_nsec ? stat->atime.tv_nsec / 1000 : 0);
190 lease_get_mtime(d_inode(dentry), &time);
191 *p++ = htonl((u32) time.tv_sec);
192 *p++ = htonl(time.tv_nsec ? time.tv_nsec / 1000 : 0);
193 *p++ = htonl((u32) stat->ctime.tv_sec);
194 *p++ = htonl(stat->ctime.tv_nsec ? stat->ctime.tv_nsec / 1000 : 0);
195
196 return p;
197 }
198
199 /* Helper function for NFSv2 ACL code */
nfs2svc_encode_fattr(struct svc_rqst * rqstp,__be32 * p,struct svc_fh * fhp,struct kstat * stat)200 __be32 *nfs2svc_encode_fattr(struct svc_rqst *rqstp, __be32 *p, struct svc_fh *fhp, struct kstat *stat)
201 {
202 return encode_fattr(rqstp, p, fhp, stat);
203 }
204
205 /*
206 * XDR decode functions
207 */
208 int
nfssvc_decode_void(struct svc_rqst * rqstp,__be32 * p,void * dummy)209 nfssvc_decode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
210 {
211 return xdr_argsize_check(rqstp, p);
212 }
213
214 int
nfssvc_decode_fhandle(struct svc_rqst * rqstp,__be32 * p,struct nfsd_fhandle * args)215 nfssvc_decode_fhandle(struct svc_rqst *rqstp, __be32 *p, struct nfsd_fhandle *args)
216 {
217 p = decode_fh(p, &args->fh);
218 if (!p)
219 return 0;
220 return xdr_argsize_check(rqstp, p);
221 }
222
223 int
nfssvc_decode_sattrargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_sattrargs * args)224 nfssvc_decode_sattrargs(struct svc_rqst *rqstp, __be32 *p,
225 struct nfsd_sattrargs *args)
226 {
227 p = decode_fh(p, &args->fh);
228 if (!p)
229 return 0;
230 p = decode_sattr(p, &args->attrs);
231
232 return xdr_argsize_check(rqstp, p);
233 }
234
235 int
nfssvc_decode_diropargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_diropargs * args)236 nfssvc_decode_diropargs(struct svc_rqst *rqstp, __be32 *p,
237 struct nfsd_diropargs *args)
238 {
239 if (!(p = decode_fh(p, &args->fh))
240 || !(p = decode_filename(p, &args->name, &args->len)))
241 return 0;
242
243 return xdr_argsize_check(rqstp, p);
244 }
245
246 int
nfssvc_decode_readargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readargs * args)247 nfssvc_decode_readargs(struct svc_rqst *rqstp, __be32 *p,
248 struct nfsd_readargs *args)
249 {
250 unsigned int len;
251 int v;
252 p = decode_fh(p, &args->fh);
253 if (!p)
254 return 0;
255
256 args->offset = ntohl(*p++);
257 len = args->count = ntohl(*p++);
258 p++; /* totalcount - unused */
259
260 len = min_t(unsigned int, len, NFSSVC_MAXBLKSIZE_V2);
261
262 /* set up somewhere to store response.
263 * We take pages, put them on reslist and include in iovec
264 */
265 v=0;
266 while (len > 0) {
267 struct page *p = *(rqstp->rq_next_page++);
268
269 rqstp->rq_vec[v].iov_base = page_address(p);
270 rqstp->rq_vec[v].iov_len = min_t(unsigned int, len, PAGE_SIZE);
271 len -= rqstp->rq_vec[v].iov_len;
272 v++;
273 }
274 args->vlen = v;
275 return xdr_argsize_check(rqstp, p);
276 }
277
278 int
nfssvc_decode_writeargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_writeargs * args)279 nfssvc_decode_writeargs(struct svc_rqst *rqstp, __be32 *p,
280 struct nfsd_writeargs *args)
281 {
282 unsigned int len, hdr, dlen;
283 struct kvec *head = rqstp->rq_arg.head;
284 int v;
285
286 p = decode_fh(p, &args->fh);
287 if (!p)
288 return 0;
289
290 p++; /* beginoffset */
291 args->offset = ntohl(*p++); /* offset */
292 p++; /* totalcount */
293 len = args->len = ntohl(*p++);
294 /*
295 * The protocol specifies a maximum of 8192 bytes.
296 */
297 if (len > NFSSVC_MAXBLKSIZE_V2)
298 return 0;
299
300 /*
301 * Check to make sure that we got the right number of
302 * bytes.
303 */
304 hdr = (void*)p - head->iov_base;
305 if (hdr > head->iov_len)
306 return 0;
307 dlen = head->iov_len + rqstp->rq_arg.page_len - hdr;
308
309 /*
310 * Round the length of the data which was specified up to
311 * the next multiple of XDR units and then compare that
312 * against the length which was actually received.
313 * Note that when RPCSEC/GSS (for example) is used, the
314 * data buffer can be padded so dlen might be larger
315 * than required. It must never be smaller.
316 */
317 if (dlen < XDR_QUADLEN(len)*4)
318 return 0;
319
320 rqstp->rq_vec[0].iov_base = (void*)p;
321 rqstp->rq_vec[0].iov_len = head->iov_len - hdr;
322 v = 0;
323 while (len > rqstp->rq_vec[v].iov_len) {
324 len -= rqstp->rq_vec[v].iov_len;
325 v++;
326 rqstp->rq_vec[v].iov_base = page_address(rqstp->rq_pages[v]);
327 rqstp->rq_vec[v].iov_len = PAGE_SIZE;
328 }
329 rqstp->rq_vec[v].iov_len = len;
330 args->vlen = v + 1;
331 return 1;
332 }
333
334 int
nfssvc_decode_createargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_createargs * args)335 nfssvc_decode_createargs(struct svc_rqst *rqstp, __be32 *p,
336 struct nfsd_createargs *args)
337 {
338 if ( !(p = decode_fh(p, &args->fh))
339 || !(p = decode_filename(p, &args->name, &args->len)))
340 return 0;
341 p = decode_sattr(p, &args->attrs);
342
343 return xdr_argsize_check(rqstp, p);
344 }
345
346 int
nfssvc_decode_renameargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_renameargs * args)347 nfssvc_decode_renameargs(struct svc_rqst *rqstp, __be32 *p,
348 struct nfsd_renameargs *args)
349 {
350 if (!(p = decode_fh(p, &args->ffh))
351 || !(p = decode_filename(p, &args->fname, &args->flen))
352 || !(p = decode_fh(p, &args->tfh))
353 || !(p = decode_filename(p, &args->tname, &args->tlen)))
354 return 0;
355
356 return xdr_argsize_check(rqstp, p);
357 }
358
359 int
nfssvc_decode_readlinkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readlinkargs * args)360 nfssvc_decode_readlinkargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd_readlinkargs *args)
361 {
362 p = decode_fh(p, &args->fh);
363 if (!p)
364 return 0;
365 args->buffer = page_address(*(rqstp->rq_next_page++));
366
367 return xdr_argsize_check(rqstp, p);
368 }
369
370 int
nfssvc_decode_linkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_linkargs * args)371 nfssvc_decode_linkargs(struct svc_rqst *rqstp, __be32 *p,
372 struct nfsd_linkargs *args)
373 {
374 if (!(p = decode_fh(p, &args->ffh))
375 || !(p = decode_fh(p, &args->tfh))
376 || !(p = decode_filename(p, &args->tname, &args->tlen)))
377 return 0;
378
379 return xdr_argsize_check(rqstp, p);
380 }
381
382 int
nfssvc_decode_symlinkargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_symlinkargs * args)383 nfssvc_decode_symlinkargs(struct svc_rqst *rqstp, __be32 *p,
384 struct nfsd_symlinkargs *args)
385 {
386 if ( !(p = decode_fh(p, &args->ffh))
387 || !(p = decode_filename(p, &args->fname, &args->flen))
388 || !(p = decode_pathname(p, &args->tname, &args->tlen)))
389 return 0;
390 p = decode_sattr(p, &args->attrs);
391
392 return xdr_argsize_check(rqstp, p);
393 }
394
395 int
nfssvc_decode_readdirargs(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readdirargs * args)396 nfssvc_decode_readdirargs(struct svc_rqst *rqstp, __be32 *p,
397 struct nfsd_readdirargs *args)
398 {
399 p = decode_fh(p, &args->fh);
400 if (!p)
401 return 0;
402 args->cookie = ntohl(*p++);
403 args->count = ntohl(*p++);
404 args->count = min_t(u32, args->count, PAGE_SIZE);
405 args->buffer = page_address(*(rqstp->rq_next_page++));
406
407 return xdr_argsize_check(rqstp, p);
408 }
409
410 /*
411 * XDR encode functions
412 */
413 int
nfssvc_encode_void(struct svc_rqst * rqstp,__be32 * p,void * dummy)414 nfssvc_encode_void(struct svc_rqst *rqstp, __be32 *p, void *dummy)
415 {
416 return xdr_ressize_check(rqstp, p);
417 }
418
419 int
nfssvc_encode_attrstat(struct svc_rqst * rqstp,__be32 * p,struct nfsd_attrstat * resp)420 nfssvc_encode_attrstat(struct svc_rqst *rqstp, __be32 *p,
421 struct nfsd_attrstat *resp)
422 {
423 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
424 return xdr_ressize_check(rqstp, p);
425 }
426
427 int
nfssvc_encode_diropres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_diropres * resp)428 nfssvc_encode_diropres(struct svc_rqst *rqstp, __be32 *p,
429 struct nfsd_diropres *resp)
430 {
431 p = encode_fh(p, &resp->fh);
432 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
433 return xdr_ressize_check(rqstp, p);
434 }
435
436 int
nfssvc_encode_readlinkres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readlinkres * resp)437 nfssvc_encode_readlinkres(struct svc_rqst *rqstp, __be32 *p,
438 struct nfsd_readlinkres *resp)
439 {
440 *p++ = htonl(resp->len);
441 xdr_ressize_check(rqstp, p);
442 rqstp->rq_res.page_len = resp->len;
443 if (resp->len & 3) {
444 /* need to pad the tail */
445 rqstp->rq_res.tail[0].iov_base = p;
446 *p = 0;
447 rqstp->rq_res.tail[0].iov_len = 4 - (resp->len&3);
448 }
449 return 1;
450 }
451
452 int
nfssvc_encode_readres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readres * resp)453 nfssvc_encode_readres(struct svc_rqst *rqstp, __be32 *p,
454 struct nfsd_readres *resp)
455 {
456 p = encode_fattr(rqstp, p, &resp->fh, &resp->stat);
457 *p++ = htonl(resp->count);
458 xdr_ressize_check(rqstp, p);
459
460 /* now update rqstp->rq_res to reflect data as well */
461 rqstp->rq_res.page_len = resp->count;
462 if (resp->count & 3) {
463 /* need to pad the tail */
464 rqstp->rq_res.tail[0].iov_base = p;
465 *p = 0;
466 rqstp->rq_res.tail[0].iov_len = 4 - (resp->count&3);
467 }
468 return 1;
469 }
470
471 int
nfssvc_encode_readdirres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_readdirres * resp)472 nfssvc_encode_readdirres(struct svc_rqst *rqstp, __be32 *p,
473 struct nfsd_readdirres *resp)
474 {
475 xdr_ressize_check(rqstp, p);
476 p = resp->buffer;
477 *p++ = 0; /* no more entries */
478 *p++ = htonl((resp->common.err == nfserr_eof));
479 rqstp->rq_res.page_len = (((unsigned long)p-1) & ~PAGE_MASK)+1;
480
481 return 1;
482 }
483
484 int
nfssvc_encode_statfsres(struct svc_rqst * rqstp,__be32 * p,struct nfsd_statfsres * resp)485 nfssvc_encode_statfsres(struct svc_rqst *rqstp, __be32 *p,
486 struct nfsd_statfsres *resp)
487 {
488 struct kstatfs *stat = &resp->stats;
489
490 *p++ = htonl(NFSSVC_MAXBLKSIZE_V2); /* max transfer size */
491 *p++ = htonl(stat->f_bsize);
492 *p++ = htonl(stat->f_blocks);
493 *p++ = htonl(stat->f_bfree);
494 *p++ = htonl(stat->f_bavail);
495 return xdr_ressize_check(rqstp, p);
496 }
497
498 int
nfssvc_encode_entry(void * ccdv,const char * name,int namlen,loff_t offset,u64 ino,unsigned int d_type)499 nfssvc_encode_entry(void *ccdv, const char *name,
500 int namlen, loff_t offset, u64 ino, unsigned int d_type)
501 {
502 struct readdir_cd *ccd = ccdv;
503 struct nfsd_readdirres *cd = container_of(ccd, struct nfsd_readdirres, common);
504 __be32 *p = cd->buffer;
505 int buflen, slen;
506
507 /*
508 dprintk("nfsd: entry(%.*s off %ld ino %ld)\n",
509 namlen, name, offset, ino);
510 */
511
512 if (offset > ~((u32) 0)) {
513 cd->common.err = nfserr_fbig;
514 return -EINVAL;
515 }
516 if (cd->offset)
517 *cd->offset = htonl(offset);
518
519 /* truncate filename */
520 namlen = min(namlen, NFS2_MAXNAMLEN);
521 slen = XDR_QUADLEN(namlen);
522
523 if ((buflen = cd->buflen - slen - 4) < 0) {
524 cd->common.err = nfserr_toosmall;
525 return -EINVAL;
526 }
527 if (ino > ~((u32) 0)) {
528 cd->common.err = nfserr_fbig;
529 return -EINVAL;
530 }
531 *p++ = xdr_one; /* mark entry present */
532 *p++ = htonl((u32) ino); /* file id */
533 p = xdr_encode_array(p, name, namlen);/* name length & name */
534 cd->offset = p; /* remember pointer */
535 *p++ = htonl(~0U); /* offset of next entry */
536
537 cd->buflen = buflen;
538 cd->buffer = p;
539 cd->common.err = nfs_ok;
540 return 0;
541 }
542
543 /*
544 * XDR release functions
545 */
546 int
nfssvc_release_fhandle(struct svc_rqst * rqstp,__be32 * p,struct nfsd_fhandle * resp)547 nfssvc_release_fhandle(struct svc_rqst *rqstp, __be32 *p,
548 struct nfsd_fhandle *resp)
549 {
550 fh_put(&resp->fh);
551 return 1;
552 }
553